Incidence of and risk factors for severe hypoglycaemia in treated type 2 diabetes mellitus patients in the UK--a nested case-control analysis.

PubMed

Bruderer, S G; Bodmer, M; Jick, S S; Bader, G; Schlienger, R G; Meier, C R

2014-09-01

To assess incidence rates (IRs) of and identify risk factors for incident severe hypoglycaemia in patients with type 2 diabetes newly treated with antidiabetic drugs. Using the UK-based General Practice Research Database, we performed a retrospective cohort study between 1994 and 2011 and a nested case-control analysis. Ten controls from the population at risk were matched to each case with a recorded severe hypoglycaemia during follow-up on general practice, years of history in the database and calendar time. Using multivariate conditional logistic regression analyses, we adjusted for potential confounders. Of 130,761 patients with newly treated type 2 diabetes (mean age 61.7 ± 13.0 years), 690 (0.5%) had an incident episode of severe hypoglycaemia recorded [estimated IR 11.97 (95% confidence interval, CI, 11.11-12.90) per 10,000 person-years (PYs)]. The IR was markedly higher in insulin users [49.64 (95% CI, 44.08-55.89) per 10,000 PYs] than in patients not using insulin [8.03 (95% CI, 7.30-8.84) per 10,000 PYs]. Based on results of the nested case-control analysis increasing age [≥ 75 vs. 20-59 years; adjusted odds ratio (OR), 2.27; 95% CI, 1.65-3.12], cognitive impairment/dementia (adjusted OR, 2.00; 95% CI, 1.37-2.91), renal failure (adjusted OR, 1.34; 95% CI, 1.04-1.71), current use of sulphonylureas (adjusted OR, 4.45; 95% CI, 3.53-5.60) and current insulin use (adjusted OR, 11.83; 95% CI, 9.00-15.54) were all associated with an increased risk of severe hypoglycaemia. Severe hypoglycaemia was recorded in 12 cases per 10,000 PYs. Risk factors for severe hypoglycaemia included increasing age, renal failure, cognitive impairment/dementia, and current use of insulin or sulphonylureas. © 2014 John Wiley & Sons Ltd.

Prenatal and Perinatal Morbidity in Children with Tic Disorders: A Mainstream School-based Population Study in Central Spain.

PubMed

Cubo, Esther; Hortigüela, Montesclaros; Jorge-Roldan, Sandra; Ciciliani, Selva Esther; Lopez, Patricia; Velasco, Leticia; Sastre, Emilio; Ausin, Vanesa; Delgado, Vanesa; Saez, Sara; Gabriel-Galán, José Trejo; Macarrón, Jesús

2014-01-01

While current research suggests that genetic factors confer the greatest risk for the development of tic disorders, studies of environmental factors are relatively few, with a lack of consistent risk factors across studies. Our aim is to analyze the association of tic disorders with exposure to prenatal and perinatal morbidity. This was a nested case-control study design. Cases and controls were selected and identified from a mainstream, school-based sample. The diagnosis of tic disorders was assigned by a movement disorder neurologist using 'Diagnostic and statistical manual of mental disorders, 4th edition, text revision' criteria, and neuropsychiatric comorbidities were screened using the Spanish computerized version of the Diagnostic Interview Schedule for Children Predictive Scale. Information regarding the exposure to pre-perinatal risk factors was collected by a retrospective review of the birth certificates. Logistic regression analyses were then performed to test the association of tic disorders with pre-perinatal risk factors. Out of 407 participants, complete pre-perinatal data were available in 153 children (64 with tics and 89 without tics). After adjusting for family history of tics, neonatal respiratory distress syndrome, body mass index, prenatal infection, and coexisting comorbid neuropsychiatric disturbances, tic disorders were associated with prenatal exposure to tobacco (odds ratio [OR] = 3.07, 95% confidence interval [CI] 1.24-7.60, p = 0.007), and cesarean section (OR = 5.78, 95% CI 1.60-20.91, p = 0.01). This nested case-control study of children with tic disorders demonstrates higher adjusted odds for tics in children with exposure to cesarean delivery and maternal smoking. Longitudinal, population-based samples are required to confirm these results.

Symptoms of anxiety and depression during pregnancy and their association with low birth weight in Chinese women: a nested case control study.

PubMed

Yang, Shaoping; Yang, Rong; Liang, Shengwen; Wang, Jing; Weaver, Nancy L; Hu, Ke; Hu, Ronghua; Trevathan, Edwin; Huang, Zhen; Zhang, Yiming; Yin, Ting; Chang, Jen Jen; Zhao, Jinzhu; Shen, Longjiao; Dong, Guanghui; Zheng, Tongzhang; Xu, Shunqing; Qian, Zhengmin; Zhang, Bin

2017-04-01

This study is a nested case control study from a population-based cohort study conducted in Wuhan, China. The aim is to estimate the association between symptoms of depression during pregnancy (DDP), anxiety during pregnancy(ADP), and depression with anxiety during pregnancy (DADP) and low birth weight (LBW) and to examine the extent to which preterm birth (PTB) moderates these associations. Logistic regression analyses were used to model associations between DDP, ADP, and DADP and LBW. Models were stratified by the presence or absence of PTB to examine moderating effects. From the cohort study, 2853 had a LBW baby (cases); 5457 pregnant women served as controls. Women with DDP or ADP only were not at higher risk of having a LBW baby, but DADP was associated with increased risk of LBW (crude OR 1.41, 95% CI 1.17-1.70; adjusted OR 1.29, 95% CI 1.07-1.57), and the significant association was particularly evident between DADP and LBW in PTB, but not in full-term births. Our data suggests that DADP is related to an increased risk of LBW and that this association is most present in PTBs.

Using full-cohort data in nested case-control and case-cohort studies by multiple imputation.

PubMed

Keogh, Ruth H; White, Ian R

2013-10-15

In many large prospective cohorts, expensive exposure measurements cannot be obtained for all individuals. Exposure-disease association studies are therefore often based on nested case-control or case-cohort studies in which complete information is obtained only for sampled individuals. However, in the full cohort, there may be a large amount of information on cheaply available covariates and possibly a surrogate of the main exposure(s), which typically goes unused. We view the nested case-control or case-cohort study plus the remainder of the cohort as a full-cohort study with missing data. Hence, we propose using multiple imputation (MI) to utilise information in the full cohort when data from the sub-studies are analysed. We use the fully observed data to fit the imputation models. We consider using approximate imputation models and also using rejection sampling to draw imputed values from the true distribution of the missing values given the observed data. Simulation studies show that using MI to utilise full-cohort information in the analysis of nested case-control and case-cohort studies can result in important gains in efficiency, particularly when a surrogate of the main exposure is available in the full cohort. In simulations, this method outperforms counter-matching in nested case-control studies and a weighted analysis for case-cohort studies, both of which use some full-cohort information. Approximate imputation models perform well except when there are interactions or non-linear terms in the outcome model, where imputation using rejection sampling works well. Copyright © 2013 John Wiley & Sons, Ltd.

Drug interactions with phenprocoumon and the risk of serious haemorrhage: a nested case-control study in a large population-based German database.

PubMed

Jobski, Kathrin; Behr, Sigrid; Garbe, Edeltraut

2011-09-01

Phenprocoumon is the most frequently used vitamin K antagonist in Germany. The aim of this study was to estimate the risk of serious bleeding as a result of the use of drugs with potential interaction with phenprocoumon. We conducted a nested case-control study in a cohort of 246,220 phenprocoumon users in the German Pharmacoepidemiological Research Database. Cases were patients hospitalised for haemorrhage of different kinds. Ten controls were matched to each case by health insurance, birth year and sex using incidence density sampling. Odds ratios (OR) with 95% confidence intervals (CI) of the risk of serious bleeding associated with combined use of phenprocoumon and potentially interacting drugs versus phenprocoumon alone were estimated using conditional logistic regression analysis. Our analyses considered multiple risk factors, such as bleeding history, other comorbidities or co-medication. Our study included 2,553 cases and 25,348 matched controls. An increased risk of bleeding was observed for the combined use of phenprocoumon and clopidogrel vs phenprocoumon use alone (OR: 1.83, 95% CI: 1.41-2.36). Antibiotic drugs associated with an increased risk of haemorrhage in the population of phenprocoumon users included the group of quinolones with ORs ranging from 2.74 (95% CI: 1.80-4.18) for ciprofloxacin to 4.40 (95% CI: 2.45-7.89) for levofloxacin, amoxicillin plus clavulanic acid (OR: 2.99, 95% CI: 1.39-6.42) and cotrimoxazole (OR 3.57, 95% CI: 2.36-5.40). Among non-steroidal anti-inflammatory drugs (NSAIDs), ketoprofen and naproxen were associated with the highest risks. Significantly elevated risks of major bleeding were mainly observed for drugs with known pharmacodynamic interaction with phenprocoumon, and less for drugs with possible pharmacokinetic interaction.

Effects of exercise and dietary habits on the occurrence of polycystic ovary syndrome over 5 years of follow-up.

PubMed

Zhang, Jing; Zhou, Kunyan; Luo, Li; Liu, Ying; Liu, Xiaofang; Xu, Liangzhi

2018-06-07

To evaluate the effects of recent and previous exercise and dietary habits on the occurrence of polycystic ovary syndrome (PCOS). The present study had a population-based case-control phase and a nested case-control phase. Women aged 12-44 years with and without PCOS were surveyed using the Semiquantitative Food Frequency Questionnaire and the International Physical Activity Questionnaire to evaluate the correlation of PCOS with recent (last 7 days) or previous (5 years ago) exercise and dietary habits. No difference in recent physical activity was found between the PCOS and control groups (case-control phase, n=1854). However, patients with PCOS had previously (5 years ago; nested case-control phase, n=1149) spent less time physical active in relation to transportation (P=0.003), housekeeping (P=0.023), walking (P<0.001), and activities of moderate intensity (P=0.008), and had spent more time sitting (P<0.001). Dietary nutrients and energy intake did not differ between the two groups (P>0.05 for all comparisons). A previous exercise habit was associated with subsequent PCOS whereas a recently acquired exercise routine was not. Women should avoid long-term sedentary lifestyle habits and focus on adding to the duration of, or enhancing the intensity of, physical activity. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Parental age and risk of genetic syndromes predisposing to nervous system tumors: nested case–control study

PubMed Central

Adel Fahmideh, Maral; Tettamanti, Giorgio; Lavebratt, Catharina; Talbäck, Mats; Mathiesen, Tiit; Lannering, Birgitta; Johnson, Kimberly J; Feychting, Maria

2018-01-01

Purpose Phacomatoses are genetic syndromes that are associated with increased risk of developing nervous system tumors. Phacomatoses are usually inherited, but many develop de novo, with unknown etiology. In this population-based study, we investigated the effect of parental age on the risk of phacomatoses in offspring. Patients and methods The study was a population-based nested case–control study. All individuals born and residing in Sweden between January 1960 and December 2010 were eligible for inclusion. Using the Patient Register, 4625 phacomatosis cases were identified and further classified as familial or nonfamilial. Ten matched controls per case were randomly selected from the eligible population. Data were analyzed using conditional logistic regression. Analyses were conducted for neurofibromatosis alone (n=2089) and other phacomatoses combined (n=2536). Results Compared with offspring of fathers aged 25–29 years, increased risk estimates of nonfamilial neurofibromatosis were found for offspring of fathers aged 35–39 years (odds ratio [OR]=1.43 [95% CI 1.16–1.74]) and ≥40 years (OR =1.74 [95% CI 1.38–2.19]). For other nonfamilial phacomatoses, the risk estimate for offspring of fathers aged ≥40 years was OR =1.23 (95% CI 1.01–1.50). Paternal age was not associated with familial phacomatoses, and no consistent association was observed with maternal age. Conclusion The findings show a consistent increase in risk of de novo occurrence of phacomatoses predisposing to nervous system tumors in offspring with increasing paternal age, most pronounced for neurofibromatosis, while maternal age did not seem to influence the risk. These findings suggest an increasing rate of new mutations in the NF1 and NF2 genes in spermatozoa of older fathers.

Ticagrelor and bradycardia: a nested case-control study.

PubMed

Turgeon, Ricky D; Fernandes, Kimberly A; Juurlink, David; Tu, Jack V; Mamdani, Muhammad

2015-12-01

Ticagrelor increases serum adenosine concentrations, slowing conduction and possibly leading to bradycardia. Clinical trial data have shown numerically, though not statistically significantly, higher rates of bradyarrhythmias with ticagrelor versus clopidogrel. Additionally, recent case reports have further raised concerns for this adverse effect. We explored the association between ticagrelor and hospitalization for bradycardia in a real-world setting. We conducted a population-based, nested case-control study of Ontario residents, 66 years of age or older, discharged after a first acute coronary syndrome by linking multiple healthcare databases. Cases included patients hospitalized for bradycardia within 1 year of starting a P2Y12 inhibitor. For each case, we identified 4 controls matched on age, sex, index date, and current use of a P2Y12 inhibitor. The exposure of interest was a prescription for ticagrelor within 90 days, with clopidogrel use as the reference group. From April 2012 to March 2014, we identified 140 cases and 560 controls who met the study criteria. We found no significant association between bradycardia and exposure to ticagrelor relative to clopidogrel in the previous 90 days prior to the index date (adjusted odds ratio 1.06, 95% confidence interval 0.65-2.21). Further adjustment for potential confounders also did not identify a significant association. Among older patients with a first acute coronary syndrome, use of ticagrelor was not associated with a greater risk of admission for bradycardia relative to clopidogrel. Copyright © 2015 John Wiley & Sons, Ltd.

Uncertain Associations of Major Bleeding and Concurrent Use of Antiplatelet Agents and Chinese Medications: A Nested Case-Crossover Study

PubMed Central

Yam, Felix K.

2017-01-01

Despite the evidence that some commonly used Chinese medications (CMs) have antiplatelet/anticoagulant effects, many patients still used antiplatelets combined with CMs. We conducted a nested case-crossover study to examine the associations between the concomitant use of antiplatelets and CMs and major bleeding using population-based health database in Taiwan. Among the cohort of 79,463 outpatients prescribed antiplatelets (e.g., aspirin and clopidogrel) continuously, 1,209 patients hospitalized with new occurring bleeding in 2012 and 2013 were included. Those recruited patients served as their own controls to compare different times of exposure to prespecified CMs (e.g., Asian ginseng and dong quai) and antiplatelet agents. The periods of case, control 1, and control 2 were defined as 1–4 weeks, 6–9 weeks, and 13–16 weeks before hospitalization, respectively. Conditional logistic regression analyses found that concurrent use of antiplatelet drugs with any of the prespecified CMs in the case period might not significantly increase the risks of bleeding over that in the control periods (OR = 1.00, 95% CI 0.51 to 1.95 and OR = 1.13, 95% CI 0.65 to 1.97). The study showed no strong relationships between hospitalization for major bleeding events and concurrent use of antiplatelet drugs with the prespecified CMs. PMID:28831288

Molecular diagnosis of strongyloidiasis in a population of an endemic area through nested-PCR.

PubMed

Sharifdini, Meysam; Keyhani, Amir; Eshraghian, Mohammad Reza; Beigom Kia, Eshrat

2018-01-01

This study is aimed to diagnose and analyze strongyloidiasis in a population of an endemic area of Iran using nested-PCR, coupled with parasitological methods. Screening of strongyloidiasis infected people using reliable diagnostic techniques are essential to decrease the mortality and morbidity associated with this infection. Molecular methods have been proved to be highly sensitive and specific for detection of Strongyloides stercoralis in stool samples. A total of 155 fresh single stool samples were randomly collected from residents of north and northwest of Khouzestan Province, Iran. All samples were examined by parasitological methods including formalin-ether concentration and nutrient agar plate culture, and molecular method of nested-PCR. Infections with S. stercoralis were analyzed according to demographic criteria. Based on the results of nested-PCR method 15 cases (9.7%) were strongyloidiasis positive. Nested-PCR was more sensitive than parasitological techniques on single stool sampling. Elderly was the most important population index for higher infectivity with S. stercoralis . In endemic areas of S. stercoralis , old age should be considered as one of the most important risk factors of infection, especially among the immunosuppressed individuals.

Parental and comorbid epilepsy in persons with bipolar disorder.

PubMed

Sucksdorff, Dan; Brown, Alan S; Chudal, Roshan; Jokiranta-Olkoniemi, Elina; Leivonen, Susanna; Suominen, Auli; Heinimaa, Markus; Sourander, Andre

2015-12-01

Population-based studies have demonstrated an overrepresentation of bipolar disorder (BPD) in individuals with epilepsy. However, few studies have examined the reverse association, i.e. comorbid epilepsy in individuals selected based on BPD diagnosis. No previous population-based study having examined the co-occurrence of BPD and epilepsy has adjusted for parental psychopathology. Such an adjustment is motivated by population-based studies reporting an overrepresentation of various types of parental psychiatric disorders in both BPD and epilepsy. Furthermore, an association between epilepsy in first-degree relatives and BPD has previously only been examined and demonstrated in a small clinical sample. The objective of this study is to examine the associations between parental and comorbid epilepsy and BPD, adjusting for parental psychopathology. This nested case-control study identified 1861 cases with BPD, age up to 25 years, 3643 matched controls, and their parents from Finnish national registers. Conditional logistic regression was used to calculate odds ratios (ORs) with 95% confidence intervals (CIs) and two-sided significance limits of p<0.05. BPD was associated with comorbid epilepsy (adjusted OR 2.53, 95% CI: 1.73-3.70) but not with parental epilepsy. Epilepsy was found in 3.33% of cases versus 1.29% of controls, 2.69% of cases' parents versus 2.53% of controls' parents. The diagnoses were register-based, not based on standardized procedures with direct ascertainment. An association between BPD and comorbid epilepsy persists even after adjusting for parental psychopathology. Lack of familial clustering of BPD and epilepsy would suggest that the elevated co-occurrence of these disorders is influenced by non-genetic factors. Copyright © 2015 Elsevier B.V. All rights reserved.

Incidence, risk factors, management and outcomes of amniotic-fluid embolism: a population-based cohort and nested case-control study.

PubMed

Fitzpatrick, K E; Tuffnell, D; Kurinczuk, J J; Knight, M

2016-01-01

To describe the incidence, risk factors, management and outcomes of amniotic-fluid embolism (AFE) over time. A population-based cohort and nested case-control study using the UK Obstetric Surveillance System (UKOSS). All UK hospitals with obstetrician-led maternity units. All women diagnosed with AFE in the UK between February 2005 and January 2014 (n = 120) and 3839 control women. Prospective case and control identification through UKOSS monthly mailing. Amniotic-fluid embolism, maternal death or permanent neurological injury. The total and fatal incidence of AFE, estimated as 1.7 and 0.3 per 100 000, respectively, showed no significant temporal trend over the study period and there was no notable temporal change in risk factors for AFE. Twenty-three women died (case fatality 19%) and seven (7%) of the surviving women had permanent neurological injury. Women who died or had permanent neurological injury were more likely to present with cardiac arrest (83% versus 33%, P < 0.001), be from ethnic-minority groups (adjusted odds ratio [OR] 2.85, 95% confidence interval [95% CI] 1.02-8.00), have had a hysterectomy (unadjusted OR 2.49, 95% CI 1.02-6.06), had a shorter time interval between the AFE event and when the hysterectomy was performed (median interval 77 minutes versus 248 minutes, P = 0.0315), and were less likely to receive cryoprecipitate (unadjusted OR 0.30, 95% CI 0.11-0.80). There is no evidence of a temporal change in the incidence of or risk factors for AFE. Further investigation is needed to establish whether earlier treatments can reverse the cascade of deterioration leading to severe outcomes. © 2015 The Authors. BJOG An International Journal of Obstetrics and Gynaecology published by John Wiley & Sons Ltd on behalf of Royal College of Obstetricians and Gynaecologists.

Impaired renal function modifies the risk of severe hypoglycaemia among users of insulin but not glyburide: a population-based nested case-control study.

PubMed

Weir, Matthew A; Gomes, Tara; Mamdani, Muhammad; Juurlink, David N; Hackam, Daniel G; Mahon, Jeffrey L; Jain, Arsh K; Garg, Amit X

2011-06-01

Little evidence justifies the avoidance of glyburide in patients with impaired renal function. We aimed to determine if renal function modifies the risk of hypoglycaemia among patients using glyburide. We conducted a nested case-control study using administrative records and laboratory data from Ontario, Canada. We included outpatients 66 years of age and older with diabetes mellitus and prescriptions for glyburide, insulin or metformin. We ascertained hypoglycaemic events using administrative records and estimated glomerular filtration rates (eGFR) using serum creatinine concentrations. From a cohort of 19,620 patients, we identified 204 cases whose eGFR was ≥ 60 mL/min/1.73 m(2) (normal renal function) and 354 cases whose eGFR was < 60 mL/min/1.73 m(2) (impaired renal function). Compared to metformin, glyburide is associated with a greater risk of hypoglycaemia in patients with both normal [adjusted odds ratio (OR) 9.0, 95% confidence interval (95% CI) 4.9-16.4] and impaired renal function (adjusted OR 6.0, 95% CI 3.8-9.5). We observed a similar relationship when comparing insulin to metformin; the risk was greater in patients with normal renal function (adjusted OR 18.7, 95% CI 10.5-33.5) compared to those with impaired renal function (adjusted OR 7.9, 95% CI 5.0-12.4). Tests of interaction showed that among glyburide users, renal function did not significantly modify the risk of hypoglycaemia, but among insulin users, impaired renal function is associated with a lower risk. In this population-based study, impaired renal function did not augment the risk of hypoglycaemia associated with glyburide use.

Inclusion of persons with disabilities in systems of social protection: a population-based survey and case–control study in Peru

PubMed Central

Bernabe-Ortiz, Antonio; Diez-Canseco, Francisco; Vasquez, Alberto; Kuper, Hannah; Walsham, Matthew; Blanchet, Karl

2016-01-01

Objective This study aims to assess the needs of people with disabilities and their level of inclusion in social protection programmes. Design Population based-survey with a nested case–control study. Setting Morropon, a semiurban district located in Piura, northern Peru. Participants For the population survey, a two-stage sampling method was undertaken using data from the most updated census available and information of each household member aged ≥5 years was collected. In the nested case–control study, only one participant, case or control, per household was included in the study. Primary and secondary outcome measures Disability was screened using the Washington Group short questionnaire. A case, defined as an individual aged ≥5 years with disabilities, was matched with one control without disabilities by sex and age (±5 years). Information was collected on socioeconomic status, education, health and rehabilitation and social protection participation. Results The survey included 3684 participants, 1848 (50.1%) females, mean age: 36.4 (SD: 21.7). A total of 290 participants (7.9%; 95% CI 7.0% to 8.7%) were classified as having disability. Adults with disabilities were more likely to be single (OR=3.40; 95% CI 1.54 to 7.51) and not to be working (OR=4.36; 95% CI 2.26 to 8.40), while those who did work were less likely to receive the national minimum wage (ie, 750 PEN or about US$265; p=0.007). People with disabilities were more likely to experience health problems. There was no difference between those enrolled in any social protection programme among participants with and without disabilities. Conclusions People with disabilities were found to have higher needs for social protection, but were not more likely to be enrolled in social protection programmes. The Peruvian social protection system should consider adding disability status to selection criteria in their cash transfer programmes as well as implementing disability-specific interventions. PMID:27566630

Review of the literature on benzene exposure and leukemia subtypes.

PubMed

Schnatter, A Robert; Rosamilia, Kim; Wojcik, Nancy C

2005-05-30

The epidemiologic literature on benzene exposure and leukemia in the MEDLINE and TOXNET databases was examined through October 2004 using the keywords "benzene", "leukemia" and "adverse health effects". This search was complemented by reviewing the reference lists from extant literature reviews and criteria documents on benzene. Published studies were characterized according to the type of industry studied and design, exposure assessment, disease classification, and control for confounding variables. Study design consisted of either cohort studies or case-control studies, which were further categorized into population-based and nested case-control studies. Disease classification considered the source of diagnostic information, whether there was clinical confirmation from medical records or histopathological, morphological and/or cytogenetic reviews, and as to whether the International Classification of Diseases (ICD) or the French-American-British (FAB) schemes were used (no studies used the Revised European-American Lymphoma (REAL) classification scheme). Nine cohort and 13 case-control studies met inclusion criteria for this review. High and significant acute myeloid leukemia risks with positive dose response relationships were identified across study designs, particularly in the "well-conducted" cohort studies and especially in more highly exposed workers in rubber, shoe, and paint industries. Risks for chronic lymphocytic leukemia (CLL) tended to show elevations in nested case-control studies, with possible dose response relationships in at least two of the three studies. However, cohort studies on CLL show no such risks. Data for chronic myeloid leukemia and acute lymphocytic leukemia are sparse and inconclusive.

Identification and medical utilization of incident cases of alcohol dependence: A population-based case-control study.

PubMed

Pan, Chun-Hung; Li, Min-Shan; Yang, Tien-Wey; Huang, Ming-Chyi; Su, Sheng-Shiang; Hung, Yen-Ni; Chen, Chiao-Chicy; Kuo, Chian-Jue

2018-05-05

Patients with alcohol dependence (AD) often seek help from medical professionals due to alcohol-related diseases, but the overall distribution of medical specialties identifying new AD cases is unclear. We investigated how such cases were identified and how medical resources were utilized before the identification of AD in a nationwide cohort. We enrolled a population-based cohort (N = 1,000,000) using the National Health Insurance Research Database of Taiwan; 8181 cases with incident AD were retrieved between January 1, 2000, and December 31, 2010. For this nested case-control study, four controls were matched for age and sex with each case based on risk-set sampling. We measured various dimensions of medical utilization before AD was diagnosed, including department visited, physical comorbidity, and medication used. Conditional logistic regression was used for estimating the variables associated with AD. Patients living in less urbanized areas who were unemployed were more likely to develop AD. The highest proportions (34.2%) of AD cases were identified in the internal medicine department, followed by the emergency (22.3%) and psychiatry (18.7%) departments. AD patients had a higher risk of comorbid chronic hepatic disease (adjusted RR = 2.72, p < 0.001) before identification of AD than controls. AD patients also had greater numbers of hospital admissions than controls, including non-psychiatric and psychiatric hospitalizations. Outpatient visit numbers were similar for AD patients and controls. The findings indicate that clinicians providing care in diverse medical settings should be prepared to screen for unhealthy alcohol use and to mitigate its detrimental effects. Copyright © 2018 Elsevier B.V. All rights reserved.

Risk factors for first trimester miscarriage--results from a UK-population-based case-control study.

PubMed

Maconochie, N; Doyle, P; Prior, S; Simmons, R

2007-02-01

The aim of this study was to examine the association between biological, behavioural and lifestyle risk factors and risk of miscarriage. Population-based case-control study. Case-control study nested within a population-based, two-stage postal survey of reproductive histories of women randomly sampled from the UK electoral register. Six hundred and three women aged 18-55 years whose most recent pregnancy had ended in first trimester miscarriage (<13 weeks of gestation; cases) and 6116 women aged 18-55 years whose most recent pregnancy had progressed beyond 12 weeks (controls). Women were questioned about socio-demographic, behavioural and other factors in their most recent pregnancy. First trimester miscarriage. After adjustment for confounding, the following were independently associated with increased risk: high maternal age; previous miscarriage, termination and infertility; assisted conception; low pre-pregnancy body mass index; regular or high alcohol consumption; feeling stressed (including trend with number of stressful or traumatic events); high paternal age and changing partner. Previous live birth, nausea, vitamin supplementation and eating fresh fruits and vegetables daily were associated with reduced risk, as were feeling well enough to fly or to have sex. After adjustment for nausea, we did not confirm an association with caffeine consumption, smoking or moderate or occasional alcohol consumption; nor did we find an association with educational level, socio-economic circumstances or working during pregnancy. The results confirm that advice to encourage a healthy diet, reduce stress and promote emotional wellbeing might help women in early pregnancy (or planning a pregnancy) reduce their risk of miscarriage. Findings of increased risk associated with previous termination, stress, change of partner and low pre-pregnancy weight are noteworthy, and we recommend further work to confirm these findings in other study populations.

Exposure to community violence and self-harm in California: A multi-level, population-based, case-control study.

PubMed

Matthay, Ellicott C; Farkas, Kriszta; Skeem, Jennifer; Ahern, Jennifer

2018-06-07

Self-harm is a leading cause of morbidity and mortality. Exposure to community violence is an important and potentially modifiable feature of the social environment that may affect self-harm, but studies to date are limited in the samples and outcomes examined. We conducted a population-based, nested case-control study. Cases were all deaths and hospital visits due to self-harm in California, 2006-2013. We frequency-matched California resident population-based controls from the American Community Survey to cases on age, gender, race/ethnicity, and year of survey/injury. We assessed past-year community violence using deaths and hospital visits due to interpersonal violence in the community of residence. We estimated risk-difference parameters that were defined to avoid extrapolation and to capture associations between changes in the distribution of community violence and the population-level risk of self-harm. After adjustment for confounders, setting past-year community violence to the lowest monthly levels observed within each community over the study period was associated with a 30.1 (95% CI: 29.6 to 30.5) per 100,000 persons per year lower risk of nonfatal self-harm, but no difference in the risk of fatal self-harm. Associations for a parameter corresponding to a hypothetical violence prevention intervention targeting high-violence communities indicated a 5% decrease in self-harm at the population level. In sensitivity analyses, results were robust. This study strengthens evidence on the relationship between community violence and self-harm. Future research should investigate reasons for differential associations by age and gender and whether community violence prevention programs have meaningful impacts on self-harm.

Risk of acute liver injury associated with use of antibiotics. Comparative cohort and nested case-control studies using two primary care databases in Europe.

PubMed

Brauer, Ruth; Douglas, Ian; Garcia Rodriguez, Luis Alberto; Downey, Gerald; Huerta, Consuelo; de Abajo, Francisco; Bate, Andrew; Feudjo Tepie, Maurille; de Groot, Mark C H; Schlienger, Raymond; Reynolds, Robert; Smeeth, Liam; Klungel, Olaf; Ruigómez, Ana

2016-03-01

To assess the impact of varying study designs, exposure and outcome definitions on the risk of acute liver injury (ALI) associated with antibiotic use. The source population comprised of patients registered in two primary care databases, in the UK and in Spain. We identified a cohort consisting of new users of antibiotics during the study period (2004-2009) and non-users during the study period or in the previous year. Cases with ALI were identified within this cohort and classified as definite or probable, based on recorded medical information. The relative risk (RR) of ALI associated with antibiotic use was computed using Poisson regression. For the nested case-control analyses, up to five controls were matched to each case by age, sex, date and practice (in CPRD) and odds ratios (OR) were computed with conditional logistic regression. The age, sex and year adjusted RRs of definite ALI in the current antibiotic use periods was 10.04 (95% CI: 6.97-14.47) in CPRD and 5.76 (95% CI: 3.46-9.59) in BIFAP. In the case-control analyses adjusting for life-style, comorbidities and use of medications, the OR of ALI for current users of antibiotics was and 5.7 (95% CI: 3.46-9.36) in CPRD and 2.6 (95% CI: 1.26-5.37) in BIFAP. Guided by a common protocol, both cohort and case-control study designs found an increased risk of ALI associated with the use of antibiotics in both databases, independent of the exposure and case definitions used. However, the magnitude of the risk was higher in CPRD compared to BIFAP. Copyright © 2016 John Wiley & Sons, Ltd.

Effectiveness of the 10-Valent Pneumococcal Conjugate Vaccine (PCV-10) in Children in Chile: A Nested Case-Control Study Using Nationwide Pneumonia Morbidity and Mortality Surveillance Data

PubMed Central

Toscano, Cristiana M.; Alencar, Gizelton P.; Alvarez, Andrés; Valenzuela, Maria T.; Andrus, Jon; del Aguila, Roberto; Hormazábal, Juan C.; Araya, Pamela; Pidal, Paola; Matus, Cuauhtemoc R.; de Oliveira, Lucia H.

2016-01-01

Background The ten-valent pneumococcal conjugate vaccine (PCV10) was introduced into the Chilean National Immunization Program (NIP) in January 2011 with a 3+1 schedule (2, 4, 6 and 12 months) without catch-up vaccination. We evaluated the effectiveness of PCV10 on pneumonia morbidity and mortality among infants during the first two years after vaccine introduction. Methods This is a population-based nested case-control study using four merged nationwide case-based electronic health data registries: live birth, vaccination, hospitalization and mortality. Children born in 2010 and 2011 were followed from two moths of age for a period of two years. Using four different case definitions of pneumonia hospitalization and/or mortality (all-cause and pneumonia related deaths), all cases and four randomly selected matched controls per case were selected. Controls were matched to cases on analysis time. Vaccination status was then assessed. Vaccine effectiveness (VE) was estimated using conditional logistic regression. Results There were a total of 497,996 children in the 2010 and 2011 Chilean live-birth cohorts. PCV10 VE was 11.2% (95%CI 8.5–13.6) when all pneumonia hospitalizations and deaths were used to define cases. VE increased to 20.7 (95%CI 17.3–23.8) when ICD10 codes used to denote viral pneumonia were excluded from the case definition. VE estimates on pneumonia deaths and all-cause deaths were 71.5 (95%CI 9.0–91.8) and 34.8 (95% CI 23.7–44.4), respectively. Conclusion PCV10 vaccination substantially reduced the number of hospitalizations due to pneumonia and deaths due to pneumonia and to all-causes over this study period. Our findings also reinforce the importance of having quality health information systems for measuring VE. PMID:27058873

Accounting for imperfect detection is critical for inferring marine turtle nesting population trends.

PubMed

Pfaller, Joseph B; Bjorndal, Karen A; Chaloupka, Milani; Williams, Kristina L; Frick, Michael G; Bolten, Alan B

2013-01-01

Assessments of population trends based on time-series counts of individuals are complicated by imperfect detection, which can lead to serious misinterpretations of data. Population trends of threatened marine turtles worldwide are usually based on counts of nests or nesting females. We analyze 39 years of nest-count, female-count, and capture-mark-recapture (CMR) data for nesting loggerhead turtles (Caretta caretta) on Wassaw Island, Georgia, USA. Annual counts of nests and females, not corrected for imperfect detection, yield significant, positive trends in abundance. However, multistate open robust design modeling of CMR data that accounts for changes in imperfect detection reveals that the annual abundance of nesting females has remained essentially constant over the 39-year period. The dichotomy could result from improvements in surveys or increased within-season nest-site fidelity in females, either of which would increase detection probability. For the first time in a marine turtle population, we compare results of population trend analyses that do and do not account for imperfect detection and demonstrate the potential for erroneous conclusions. Past assessments of marine turtle population trends based exclusively on count data should be interpreted with caution and re-evaluated when possible. These concerns apply equally to population assessments of all species with imperfect detection.

Multiple imputation of missing data in nested case-control and case-cohort studies.

PubMed

Keogh, Ruth H; Seaman, Shaun R; Bartlett, Jonathan W; Wood, Angela M

2018-06-05

The nested case-control and case-cohort designs are two main approaches for carrying out a substudy within a prospective cohort. This article adapts multiple imputation (MI) methods for handling missing covariates in full-cohort studies for nested case-control and case-cohort studies. We consider data missing by design and data missing by chance. MI analyses that make use of full-cohort data and MI analyses based on substudy data only are described, alongside an intermediate approach in which the imputation uses full-cohort data but the analysis uses only the substudy. We describe adaptations to two imputation methods: the approximate method (MI-approx) of White and Royston () and the "substantive model compatible" (MI-SMC) method of Bartlett et al. (). We also apply the "MI matched set" approach of Seaman and Keogh () to nested case-control studies, which does not require any full-cohort information. The methods are investigated using simulation studies and all perform well when their assumptions hold. Substantial gains in efficiency can be made by imputing data missing by design using the full-cohort approach or by imputing data missing by chance in analyses using the substudy only. The intermediate approach brings greater gains in efficiency relative to the substudy approach and is more robust to imputation model misspecification than the full-cohort approach. The methods are illustrated using the ARIC Study cohort. Supplementary Materials provide R and Stata code. © 2018, The International Biometric Society.

Psychiatric comorbidity may not predict suicide during and after hospitalization. A nested case-control study with blinded raters.

PubMed

Walby, Fredrik A; Odegaard, Erik; Mehlum, Lars

2006-06-01

To investigate the differential impact of DSM-IV axis-I and axis-II disorders on completed suicide and to study if psychiatric comorbidity increases the risk of suicide in currently and previously hospitalized psychiatric patients. A nested case-control design based on case notes from 136 suicides and 166 matched controls. All cases and controls were rediagnosed using the SCID-CV for axis-I and the DSM-IV criteria for axis-II disorders and the inter-rater reliability was satisfactory. Raters were blind to the case and control status and the original hospital diagnoses. Depressive disorders and bipolar disorders were associated with an increased risk of suicide. No such effect was found for comorbidity between axis-I disorders and for comorbidity between axis-I and axis-II disorders. Psychiatric diagnoses, although made using a structured and criteria-based approach, was based on information recorded in case notes. Axis-II comorbidity could only be investigated at an aggregated level. Psychiatric comorbidity did not predict suicide in this sample. Mood disorders did, however, increase the risk significantly independent of history of previous suicide attempts. Both findings can inform identification and treatment of patients at high risk for completed suicide.

Estimating total population size for adult female sea turtles: Accounting for non-nesters

USGS Publications Warehouse

Kendall, W.L.; Richardson, J.I.; Rees, Alan F.

2008-01-01

Assessment of population size and changes therein is important to sea turtle management and population or life history research. Investigators might be interested in testing hypotheses about the effect of current population size or density (number of animals per unit resource) on future population processes. Decision makers might want to determine a level of allowable take of individual turtles of specified life stage. Nevertheless, monitoring most stages of sea turtle life histories is difficult, because obtaining access to individuals is difficult. Although in-water assessments are becoming more common, nesting females and their hatchlings remain the most accessible life stages. In some cases adult females of a given nesting population are sufficiently philopatric that the population itself can be well defined. If a well designed tagging study is conducted on this population, survival, breeding probability, and the size of the nesting population in a given year can be estimated. However, with published statistical methodology the size of the entire breeding population (including those females skipping nesting in that year) cannot be estimated without assuming that each adult female in this population has the same probability of nesting in a given year (even those that had just nested in the previous year). We present a method for estimating the total size of a breeding population (including nesters those skipping nesting) from a tagging study limited to the nesting population, allowing for the probability of nesting in a given year to depend on an individual's nesting status in the previous year (i.e., a Markov process). From this we further develop estimators for rate of growth from year to year in both nesting population and total breeding population, and the proportion of the breeding population that is breeding in a given year. We also discuss assumptions and apply these methods to a breeding population of hawksbill sea turtles (Eretmochelys imbricata) from the Caribbean. We anticipate that this method could also be useful for in-water studies of well defined populations.

Dietary trace element intake and liver cancer risk: Results from two population-based cohorts in China.

PubMed

Ma, Xiao; Yang, Yang; Li, Hong-Lan; Zheng, Wei; Gao, Jing; Zhang, Wei; Yang, Gong; Shu, Xiao-Ou; Xiang, Yong-Bing

2017-03-01

Dietary factors have been hypothesized to affect the risk of liver cancer via various mechanisms, but the influence has been not well studied and the evidence is conflicting. We investigated associations of dietary trace element intake, assessed through a validated food frequency questionnaire, with risk of liver cancer in two prospective cohort studies of 132,765 women (1997-2013) and men (2002-2013) in Shanghai, China. The associations were first evaluated in cohort studies and further assessed in a case-control study nested within these cohorts adjusting for hepatitis B virus infection. For cohort analyses, Cox proportional hazard models were used to estimate hazard ratios and 95% confidence intervals. For nested case-control analyses, conditional logistic regression was used to calculate odds ratios and 95% confidence intervals. After a median follow-up time of 15.2 years for the Shanghai Women's Health Study and 9.3 years for the Shanghai Men's Health Study, 192 women and 344 men developed liver cancer. Dietary intake of manganese was inversely associated with liver cancer risk (highest vs. lowest quintile, HR = 0.51, 95% CI: 0.35-0.73; p trend  = 0.001). Further adjustment for hepatitis B virus infection in the nested case-control study yielded a similar result (highest vs. lowest quintile, OR = 0.38, 95% CI: 0.21-0.69; p trend  < 0.001). No significant association was found between dietary intake of selenium, iron, zinc, copper and liver cancer risk. The results suggest that higher intake of manganese may be associated with a lower risk of liver cancer in China. © 2016 UICC.

Direct medical costs of constipation in children over 15 years: a population-based birth cohort

PubMed Central

Choung, Rok Seon; Shah, Nilay D.; Chitkara, Denesh; Branda, Megan E.; Van Tilburg, Miranda A.; Whitehead, William E.; Katusic, Slavica K.; Locke, G. Richard; Talley, Nicholas J.

2011-01-01

Background Although direct medical costs for constipation-related medical visits are thought to be high, to date there have been no studies examining if longitudinal resource utilization is persistently elevated in children with constipation. Our aim was to estimate the incremental direct medical costs and types of health care utilization associated with constipation from childhood to early adulthood. Methods A nested case-control study was conducted to evaluate the incremental costs associated with constipation. The original sample consisted of 5,718 children in a population-based birth cohort who were born during 1976–1982 in Rochester, MN. The cases included individuals who presented to medical facilities with constipation. The controls were matched and randomly selected among all non-cases in the sample. Direct medical costs for cases and controls were collected from the time subjects were between 5–18 years of age or until the subject emigrated from the community. Results We identified 250 cases with a diagnosis of constipation in the birth cohort. While the mean inpatient costs for cases were $9994 (95% CI=2538, 37201) compared to $2391 (95% CI=923, 7452) for controls (p=0.22) over the time period, the mean outpatient costs for cases were $13927 (95% CI=11325, 16525) compared to $3448 (95% CI=3771, 4621) for controls (p<0.001) over the same time period. The mean annual number emergency department visits for cases were 0.66 (95% CI=0.62, 0.70) compared to 0.34 (95% CI=0.32, 0.35) for controls (p<0.0001). Conclusion Individuals with constipation have higher medical care utilization. Outpatient costs and ER utilization were significantly greater for individuals with constipation from childhood to early adulthood. PMID:20890220

Diversity of great gray owl nest sites and nesting habitats in California

Treesearch

Joanna X. Wu; Rodney B. Siegel; Helen L. Loffland; Morgan W. Tingley; Sarah L. Stock; Kevin N. Roberts; John J. Keane; Joseph R. Medley; Roy Bridgman; Chris Stermer

2015-01-01

The great gray owl (Strix nebulosa) is listed by the state of California as endangered, with a population estimate of fewer than 300 individuals in the state. Nest-site availability has been suggested as a limiting factor for population growth in California, but information on nest types and nesting habitat has been based on a small number of nests...

Direct medical costs of constipation from childhood to early adulthood: a population-based birth cohort study.

PubMed

Choung, Rok Seon; Shah, Nilay D; Chitkara, Denesh; Branda, Megan E; Van Tilburg, Miranda A; Whitehead, William E; Katusic, Slavica K; Locke, G Richard; Talley, Nicholas J

2011-01-01

Although direct medical costs for constipation-related medical visits are thought to be high, to date there have been no studies examining whether longitudinal resource use is persistently elevated in children with constipation. Our aim was to estimate the incremental direct medical costs and types of health care use associated with constipation from childhood to early adulthood. A nested case-control study was conducted to evaluate the incremental costs associated with constipation. The original sample consisted of 5718 children in a population-based birth cohort who were born during 1976 to 1982 in Rochester, MN. The cases included individuals who presented to medical facilities with constipation. The controls were matched and randomly selected among all noncases in the sample. Direct medical costs for cases and controls were collected from the time subjects were between 5 and 18 years of age or until the subject emigrated from the community. We identified 250 cases with a diagnosis of constipation in the birth cohort. Although the mean inpatient costs for cases were $9994 (95% Confidence interval [CI] 2538-37,201) compared with $2391 (95% CI 923-7452) for controls (P = 0.22) during the time period, the mean outpatient costs for cases were $13,927 (95% CI 11,325-16,525) compared with $3448 (95% CI 3771-4621) for controls (P < 0.001) during the same time period. The mean annual number of emergency department visits for cases was 0.66 (95% CI 0.62-0.70) compared with 0.34 (95% CI 0.32-0.35) for controls (P < 0.0001). Individuals with constipation have higher medical care use. Outpatient costs and emergency department use were significantly greater for individuals with constipation from childhood to early adulthood.

Effectiveness of the live attenuated rotavirus vaccine produced by a domestic manufacturer in China studied using a population-based case-control design.

PubMed

Zhen, Shan-Shan; Li, Yue; Wang, Song-Mei; Zhang, Xin-Jiang; Hao, Zhi-Yong; Chen, Ying; Wang, Dan; Zhang, Yan-Hong; Zhang, Zhi-Yong; Ma, Jing-Chen; Zhou, Peng; Zhang, Zhen; Jiang, Zhi-Wei; Zhao, Yu-Liang; Wang, Xuan-Yi

2015-10-01

A universal rotavirus (RV) immunization program is a potentially cost-effective measure for preventing RV infection in China. However, the efficacy of the only licensed RV vaccine (Lanzhou lamb rotavirus vaccine, LLR), which is made by a domestic manufacturer, has not been proven by a properly designed clinical trial. In October 2011 to March 2012, to measure the potential protection provided by LLR, a case-control study nested in a population-based active diarrhea surveillance study of children <5 years of age was conducted in rural Zhengding county. During the study period, 308 episodes of diarrhea were identified as being caused by RV infection, resulting in an incidence rate of 48.0/1000 people/year. The predominant RV serotype was G3 (61.5%), followed by G1 (15.2%), and G9 (6.5%). Overall, a protection of 35.0% (95% confidence interval (CI), 13.0%-52.0%) was identified, and higher protection was found among moderate RV gastroenteritis cases caused by the serotype G3 (52.0% 95% CI: 2.0%-76.1%). A concurrently conducted case-control study comparing non-RV viral diarrheal cases with non-diarrheal controls in the same population found that the RV vaccine offered no protection against non-RV diarrhea. Even under a less ideal immunization schedule, the oral LLR conferred a certain level of protection against RV gastroenteritis. However, further studies are needed to understand the full characteristics of the LLR, including its efficacy when administered following the optimal regimen, the potential risk of inducing intussusception, and the direct and indirect protective effects of LLR.

Nested PCR for specific diagnosis of Taenia solium taeniasis.

PubMed

Mayta, Holger; Gilman, Robert H; Prendergast, Emily; Castillo, Janeth P; Tinoco, Yeny O; Garcia, Hector H; Gonzalez, Armando E; Sterling, Charles R

2008-01-01

Taeniasis due to Taenia solium is a disease with important public health consequences, since the larval stage is not exclusive to the animal intermediate, the pig, but also infects humans, causing neurocysticercosis. Early diagnosis and treatment of T. solium tapeworm carriers is important to prevent human cysticercosis. Current diagnosis based on microscopic observation of eggs lacks both sensitivity and specificity. In the present study, a nested-PCR assay targeting the Tso31 gene was developed for the specific diagnosis of taeniasis due to T. solium. Initial specificity and sensitivity testing was performed using stored known T. solium-positive and -negative samples. The assay was further analyzed under field conditions by conducting a case-control study of pretreatment stool samples collected from a population in an area of endemicity. Using the archived samples, the assay showed 97% (31/32) sensitivity and 100% (123/123) specificity. Under field conditions, the assay had 100% sensitivity and specificity using microscopy/enzyme-linked immunosorbent assay coproantigen testing as the gold standards. The Tso31 nested PCR described here might be a useful tool for the early diagnosis and prevention of taeniasis/cysticercosis.

Trimethoprim-sulfamethoxazole induced hyperkalaemia in elderly patients receiving spironolactone: nested case-control study.

PubMed

Antoniou, Tony; Gomes, Tara; Mamdani, Muhammad M; Yao, Zhan; Hellings, Chelsea; Garg, Amit X; Weir, Matthew A; Juurlink, David N

2011-09-12

To characterise the risk of admission to hospital for hyperkalaemia in elderly patients treated with trimethoprim-sulfamethoxazole in combination with spironolactone. Population based nested case-control study. Ontario, Canada, from 1 April 1992 to 1 March 2010. Cases were residents of Ontario aged 66 years or above receiving chronic treatment with spironolactone and admitted to hospital with hyperkalaemia within 14 days of receiving a prescription for either trimethoprim-sulfamethoxazole, amoxicillin, norfloxacin, or nitrofurantoin. Up to four controls for each case were identified from the same cohort, matched on age, sex, and presence or absence of chronic kidney disease and diabetes, and required to have received one of the study antibiotics within 14 days before the case's index date. Odds ratio for association between admission to hospital with hyperkalaemia and receipt of a study antibiotic in the preceding 14 days, adjusted for conditions and drugs that may influence risk of hyperkalaemia. During the 18 year study period, 6903 admissions for hyperkalaemia were identified, 306 of which occurred within 14 days of antibiotic use. Of these, 248 (81%) cases were matched to 783 controls. 10.8% (17,859/165,754) of spironolactone users received at least one prescription for trimethoprim-sulfamethoxazole. Compared with amoxicillin, prescription of trimethoprim-sulfamethoxazole was associated with a marked increase in the risk of admission to hospital for hyperkalaemia (adjusted odds ratio 12.4, 95% confidence interval 7.1 to 21.6). The population attributable fraction was 59.7%, suggesting that approximately 60% of all cases of hyperkalaemia in older patients taking spironolactone and treated with an antibiotic for a urinary tract infection could be avoided if trimethoprim-sulfamethoxazole was not prescribed. Treatment with nitrofurantoin was also associated with an increase in the risk of hyperkalaemia (adjusted odds ratio 2.4, 1.3 to 4.6), but no such risk was found with norfloxacin (adjusted odds ratio 1.6, 0.8 to 3.4) Among older patients receiving spironolactone, treatment with trimethoprim-sulfamethoxazole was associated with a major increase in the risk of admission to hospital for hyperkalaemia. This drug combination should be avoided when possible.

Respiratory effect of beta-blockers in people with asthma and cardiovascular disease: population-based nested case control study.

PubMed

Morales, Daniel R; Lipworth, Brian J; Donnan, Peter T; Jackson, Cathy; Guthrie, Bruce

2017-01-27

Cardiovascular disease (CVD) is a common comorbidity in people with asthma. However, safety concerns have caused heterogeneity in clinical guideline recommendations over the use of cardioselective beta-blockers in people with asthma and CVD, partly because risk in the general population has been poorly quantified. The aim of this study was to measure the risk of asthma exacerbations with beta-blockers prescribed to a general population with asthma and CVD. Linked data from the UK Clinical Practice Research Datalink was used to perform nested case-control studies among people with asthma and CVD matched on age, sex and calendar time. Adjusted incidence rate ratios (IRR) were calculated for the association between oral beta-blocker use and moderate asthma exacerbations (rescue oral steroids) or severe asthma exacerbations (hospitalisation or death) using conditional logistic regression. The cohort consisted of 35,502 people identified with active asthma and CVD, of which 14.1% and 1.2% were prescribed cardioselective and non-selective beta-blockers, respectively, during follow-up. Cardioselective beta-blocker use was not associated with a significantly increased risk of moderate or severe asthma exacerbations. Consistent results were obtained following sensitivity analyses and a self-controlled case series approach. In contrast, non-selective beta-blockers were associated with a significantly increased risk of moderate asthma exacerbations when initiated at low to moderate doses (IRR 5.16, 95% CI 1.83-14.54, P = 0.002), and both moderate and severe exacerbations when prescribed chronically at high dose (IRR 2.68, 95% CI 1.08-6.64, P = 0.033 and IRR 12.11, 95% CI 1.02-144.11, P = 0.048, respectively). Cardioselective beta-blockers prescribed to people with asthma and CVD were not associated with a significantly increased risk of moderate or severe asthma exacerbations and potentially could be used more widely when strongly indicated.

Recruitment of participants through community pharmacies for a pharmacogenetic study of antihypertensive drug treatment.

PubMed

van Wieren-de Wijer, Diane B M A; Maitland-van der Zee, Anke-Hilse; de Boer, Anthonius; Stricker, Bruno H Ch; Kroon, Abraham A; de Leeuw, Peter W; Bozkurt, O; Klungel, Olaf H

2009-04-01

To describe the design, recruitment and baseline characteristics of participants in a community pharmacy based pharmacogenetic study of antihypertensive drug treatment. Participants enrolled from the population-based Pharmaco-Morbidity Record Linkage System. We designed a nested case-control study in which we will assess whether specific genetic polymorphisms modify the effect of antihypertensive drugs on the risk of myocardial infarction. In this study, cases (myocardial infarction) and controls were recruited through community pharmacies that participate in PHARMO. The PHARMO database comprises drug dispensing histories of about 2,000,000 subjects from a representative sample of Dutch community pharmacies linked to the national registrations of hospital discharges. In total we selected 31010 patients (2777 cases and 28233 controls) from the PHARMO database, of whom 15973 (1871 cases, 14102 controls) were approached through their community pharmacy. Overall response rate was 36.3% (n = 5791, 794 cases, 4997 controls), whereas 32.1% (n = 5126, 701 cases, 4425 controls) gave informed consent to genotype their DNA. As expected, several cardiovascular risk factors such as smoking, body mass index, hypercholesterolemia, and diabetes mellitus were more common in cases than in controls. Furthermore, cases more often used beta-blockers and calcium-antagonists, whereas controls more often used thiazide diuretics, ACE-inhibitors, and angiotensin-II receptor blockers. We have demonstrated that it is feasible to select patients from a coded database for a pharmacogenetic study and to approach them through community pharmacies, achieving reasonable response rates and without violating privacy rules.

Effect of Tubal Sterilization Technique on Risk of Serous Ovarian and Primary Peritoneal Carcinoma

PubMed Central

LESSARD-ANDERSON, Collette R.; HANDLOGTEN, Kathryn S.; MOLITOR, Rochelle J.; DOWDY, Sean C.; CLIBY, William A.; WEAVER, Amy L.; SAUVER, Jennifer ST.; BAKKUM-GAMEZ, Jamie N.

2014-01-01

Objective To determine the effect of excisional tubal sterilization on subsequent development of serous epithelial ovarian cancer (EOC) or primary peritoneal cancer (PPC). Methods We performed a population-based, nested case-control study using the Rochester Epidemiology Project. We identified all patients with a diagnosis of serous EOC or PPC from 1966 through 2009. Each case was age-matched to 2 controls without either diagnosis. Odds ratios (ORs) and corresponding 95% CIs were estimated from conditional logistic regression models. Models were adjusted for prior hysterectomy, prior salpingo-oophorectomy, oral contraceptive use, endometriosis, infertility, gravidity, and parity. Results In total, we identified 194 cases of serous EOC and PPC during the study period and matched them with 388 controls (mean [SD] age, 61.4 [15.2] years). Fourteen cases (7.2%) and 46 controls (11.9%) had undergone tubal sterilization. Adjusted risk of serous EOC or PPC was slightly lower after any tubal sterilization (OR, 0.59 [95% CI, 0.29–1.17]; P=.13). The rate of excisional tubal sterilization was lower in cases than controls (2.6% vs 6.4%). Adjusted risk of serous EOC and PPC was decreased by 64% after excisional tubal sterilization (OR, 0.36 [95% CI, 0.13–1.02]; P=.054) compared with those without sterilization or with nonexcisional tubal sterilization. Conclusions We present a population-based investigation of the effects of excisional tubal sterilization on the risk of serous EOC and PPC. Excisional methods may confer greater risk reduction than other sterilization methods. PMID:25316178

A Role for Nonapeptides and Dopamine in Nest-Building Behaviour

PubMed Central

Hall, Z J; Healy, S D; Meddle, S L

2015-01-01

During nest building in zebra finches (Taeniopygia guttata), several regions in the social behaviour network and the dopaminergic reward system, which are two neural circuits involved in social behaviour, appear to be active in male and female nest-building finches. Because the nonapeptides, mesotocin and vasotocin and the neurotransmitter, dopamine, play important roles in avian social behaviour, we tested the hypothesis that mesotocinergic-vasotocinergic and dopaminergic neuronal populations in the social behaviour network and dopaminergic reward system, respectively, are active during nest building. We combined immunohistochemistry for Fos (an indirect marker of neuronal activity) and vasotocin, mesotocin or tyrosine hydroxylase on brain tissue from nest-building and non-nest-building male and female zebra finches and compared Fos immunoreactivity in these neuronal populations with the variation in nest-building behaviour. Fos immunoreactivity in all three types of neuronal populations increased with some aspect of nest building: (i) higher immunoreactivity in a mesotocinergic neuronal population of nest-building finches compared to controls; (ii) increased immunoreactivity in the vasotocinergic neuronal populations in relation to the amount of material picked up by nest-building males and the length of time that a male spent in the nest with his mate; and (iii) increased immunoreactivity in a dopaminergic neuronal population in relation to the length of time that a male nest-building finch spent in the nest with his mate. Taken together, these findings provide evidence for a role of the mesotocinergic-vasotocinergic and dopaminergic systems in avian nest building. PMID:25514990

Whole exome sequencing in 75 high-risk families with validation and replication in independent case-control studies identifies TANGO2, OR5H14, and CHAD as new prostate cancer susceptibility genes.

PubMed

Karyadi, Danielle M; Geybels, Milan S; Karlins, Eric; Decker, Brennan; McIntosh, Laura; Hutchinson, Amy; Kolb, Suzanne; McDonnell, Shannon K; Hicks, Belynda; Middha, Sumit; FitzGerald, Liesel M; DeRycke, Melissa S; Yeager, Meredith; Schaid, Daniel J; Chanock, Stephen J; Thibodeau, Stephen N; Berndt, Sonja I; Stanford, Janet L; Ostrander, Elaine A

2017-01-03

Prostate cancer (PCa) susceptibility is defined by a continuum from rare, high-penetrance to common, low-penetrance alleles. Research to date has concentrated on identification of variants at the ends of that continuum. Taking an alternate approach, we focused on the important but elusive class of low-frequency, moderately penetrant variants by performing disease model-based variant filtering of whole exome sequence data from 75 hereditary PCa families. Analysis of 341 candidate risk variants identified nine variants significantly associated with increased PCa risk in a population-based, case-control study of 2,495 men. In an independent nested case-control study of 7,121 men, there was risk association evidence for TANGO2 p.Ser17Ter and the established HOXB13 p.Gly84Glu variant. Meta-analysis combining the case-control studies identified two additional variants suggestively associated with risk, OR5H14 p.Met59Val and CHAD p.Ala342Asp. The TANGO2 and HOXB13 variants co-occurred in cases more often than expected by chance and never in controls. Finally, TANGO2 p.Ser17Ter was associated with aggressive disease in both case-control studies separately. Our analyses identified three new PCa susceptibility alleles in the TANGO2, OR5H14 and CHAD genes that not only segregate in multiple high-risk families but are also of importance in altering disease risk for men from the general population. This is the first successful study to utilize sequencing in high-risk families for the express purpose of identifying low-frequency, moderately penetrant PCa risk mutations.

The ethological trap: functional and numerical responses of highly efficient invasive predators driving prey extinctions.

PubMed

Spencer, Ricky-John; Van Dyke, James U; Thompson, Michael B

2016-10-01

Ecological traps are threats to organisms, and exist in a range of biological systems. A subset of ecological trap theory is the "ethological trap," whereby behaviors canalized by past natural selection become traps when environments change rapidly. Invasive predators are major threats to imperiled species and their ability to exploit canalized behaviors of naive prey is particularly important for the establishment of the predator and the decline of the native prey. Our study uses ecological theory to demonstrate that invasive predator controls require shifts in management priorities. Total predation rate (i.e., total response) is the product of both the functional response and numerical response of predators to prey. Functional responses are the changes in the rate of prey consumption by individual predators, relative to prey abundance. Numerical responses are the aggregative rates of prey consumption by all predators relative to prey density, which change with predator density via reproduction or migration, in response to changes in prey density. Traditional invasive predator management methods focus on reducing predator populations, and thus manage for numerical responses. These management efforts fail to manage for functional responses, and may not eliminate impacts of highly efficient individual predators. We explore this problem by modeling the impacts of functional and numerical responses of invasive foxes depredating imperiled Australian turtle nests. Foxes exhibit exceptionally efficient functional responses. A single fox can destroy >95% of turtle nests in a nesting area, which eliminates juvenile recruitment. In this case, the ethological trap is the "Arribada" nesting strategy, an emergent behavior whereby most turtles in a population nest simultaneously in the same nesting grounds. Our models show that Arribada nesting events do not oversaturate foxes, and small numbers of foxes depredate all of the nests in a given Arribada. Widely scattering nests may reduce fox predation rates, but the long generation times of turtles combined with their rapid recent decline suggests that evolutionary responses in nesting strategy may be unlikely. Our study demonstrates that reducing populations of highly efficient invasive predators is insufficient for preserving native prey species. Instead, management must reduce individual predator efficiency, independent of reducing predator population size. © 2016 by the Ecological Society of America.

Better cancer biomarker discovery through better study design.

PubMed

Rundle, Andrew; Ahsan, Habibul; Vineis, Paolo

2012-12-01

High-throughput laboratory technologies coupled with sophisticated bioinformatics algorithms have tremendous potential for discovering novel biomarkers, or profiles of biomarkers, that could serve as predictors of disease risk, response to treatment or prognosis. We discuss methodological issues in wedding high-throughput approaches for biomarker discovery with the case-control study designs typically used in biomarker discovery studies, especially focusing on nested case-control designs. We review principles for nested case-control study design in relation to biomarker discovery studies and describe how the efficiency of biomarker discovery can be effected by study design choices. We develop a simulated prostate cancer cohort data set and a series of biomarker discovery case-control studies nested within the cohort to illustrate how study design choices can influence biomarker discovery process. Common elements of nested case-control design, incidence density sampling and matching of controls to cases are not typically factored correctly into biomarker discovery analyses, inducing bias in the discovery process. We illustrate how incidence density sampling and matching of controls to cases reduce the apparent specificity of truly valid biomarkers 'discovered' in a nested case-control study. We also propose and demonstrate a new case-control matching protocol, we call 'antimatching', that improves the efficiency of biomarker discovery studies. For a valid, but as yet undiscovered, biomarker(s) disjunctions between correctly designed epidemiologic studies and the practice of biomarker discovery reduce the likelihood that true biomarker(s) will be discovered and increases the false-positive discovery rate. © 2012 The Authors. European Journal of Clinical Investigation © 2012 Stichting European Society for Clinical Investigation Journal Foundation.

Eczema in early childhood, sociodemographic factors and lifestyle habits are associated with food allergy: a nested case-control study.

PubMed

Ben-Shoshan, Moshe; Soller, Lianne; Harrington, Daniel W; Knoll, Megan; La Vieille, Sebastian; Fragapane, Joseph; Joseph, Lawrence; St Pierre, Yvan; Wilson, Kathie; Elliott, Susan J; Clarke, Ann E

2015-01-01

Studies suggest an increase in food allergy prevalence over the last decade, but the contributing factors remain unknown. The aim of this study was to evaluate the association between the most common food allergies and atopic history, sociodemographic characteristics and lifestyle habits. We conducted a case-control study nested within the SPAACE study (Surveying Prevalence of Food Allergy in All Canadian Environments) – a cross-Canada, random telephone survey. Cases consisted of individuals with probable food allergy (self-report of convincing symptoms and/or physician diagnosis) to milk, egg, peanut, tree nut, shellfish, fish, wheat, soy, or sesame. Controls consisted of nonallergic individuals, matched for age. Cases and controls were queried on personal and family history of atopy, sociodemographic characteristics and lifestyle habits. Multivariate logistic regression was used to evaluate the association between atopy, sociodemographic characteristics and lifestyle habits with probable food allergy. Between September 2010 and September 2011, 480 cases and 4,950 controls completed the questionnaire. For all 9 allergens, factors associated with a higher risk of probable allergy were as follows: (1) personal history of eczema (in the first 2 years of life), asthma or hay fever (odds ratio, OR 2.3, 95% CI 1.6-3.5; OR 2.8, 95% CI 2.2-3.6, and OR 2.3, 95% CI 1.8-3.0, respectively), (2) maternal, paternal or sibling's food allergy (OR 3.7, 95% CI 2.5-5.6; OR 3.0, 95% CI 1.8-5.1, and OR 3.1, 95% CI 2.2-4.2), (3) high household income (top 20%; OR 1.5, 95% CI 1.2-2.0). Males and older individuals were less likely to have food allergy (OR 0.7, 95% CI 0.6-0.9, and OR 0.99, 95% CI 0.99-1.00). Eczema in the first 2 years of life was the strongest risk factor for egg, peanut, tree nut and fish allergy. This is the largest population-based nested case-control study exploring factors associated with food allergies. Our results reveal that, in addition to previously reported factors, eczema in the first 2 years of life is consistently associated with food allergies. © 2015 S. Karger AG, Basel.

Cardiovascular health status and metabolic syndrome in Ecuadorian natives/Mestizos aged 40 years or more with and without stroke and ischemic heart disease--an atahualpa project case-control nested study.

PubMed

Del Brutto, Oscar H; Mera, Robertino M; Montalván, Martha; Del Brutto, Victor J; Zambrano, Mauricio; Santamaría, Milton; Tettamanti, Daniel

2014-04-01

Knowledge of regional-specific cardiovascular risk factors is mandatory to reduce the growing burden of stroke and ischemic heart disease in Latin American populations. We conducted a population-based case-control study to assess which risk factors are associated with the occurrence of vascular events in natives/mestizos living in rural coastal Ecuador. We assessed the cardiovascular health (CVH) status and the presence of the metabolic syndrome in all Atahualpa residents aged 40 years or more with stroke and ischemic heart disease and in randomly selected healthy persons to evaluate differences in the prevalence of such risk factors between patients and controls. A total of 120 persons (24 with stroke or ischemic heart disease and 96 matched controls) were included. A poor CVH status (according to the American Heart Association) was found in 87.5% case-patients and 81.3% controls (P = .464). The metabolic syndrome was present in the same proportion (58.3%) of case-patients and controls. Likewise, both sets of risk factors (poor CVH status and the metabolic syndrome) were equally prevalent among both groups (58.3% versus 49%, P = .501). This case-control study suggests that none of the measured risk factors is associated with the occurrence of vascular events. It is possible that some yet unmeasured risk factors or an unknown genetic predisposition may account for a sizable proportion of stroke and ischemic heart disease occurring in the native/mestizo population of rural coastal Ecuador. Copyright © 2014 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Lower omega-3 fatty acids are associated with the presence of anti-cyclic citrullinated peptide autoantibodies in a population at risk for future rheumatoid arthritis: a nested case-control study

PubMed Central

Gan, Ryan W.; Young, Kendra A.; Zerbe, Gary O.; Demoruelle, M. Kristen; Weisman, Michael H.; Buckner, Jane H.; Gregersen, Peter K.; Mikuls, Ted R.; O’Dell, James R.; Keating, Richard M.; Clare-Salzler, Michael J.; Deane, Kevin D.; Holers, V. Michael

2016-01-01

Objective. The aim of this study was to investigate omega-3 fatty acid (FA) supplement use and omega-3 FAs in erythrocyte membranes [omega-3 FA % in erythrocyte membranes (RBC)] and their association with anti-CCP autoantibodies in a population without RA, but who are at genetic risk for RA. Methods. The multicentre Studies of the Etiology of RA (SERA) cohort includes RA-free subjects who are first-degree relatives of RA probands or are enriched with the HLA-DR4 allele. In a nested case-control study, 30 SERA cases were identified who were anti-CCP2 antibody positive. We further identified 47 autoantibody negative controls, frequency matched to cases on age at study visit, sex, race and study site. Anti-CCP2 status, self-reported omega-3 FA supplement use and omega-3 FA % in RBCs were obtained from a single visit. Results. Anti-CCP2 positive cases were less likely than controls to report omega-3 FA supplement use (odds ratio: 0.14; 95% CI 0.03, 0.68). In addition, the likelihood of anti-CCP2 positivity was inversely associated with total omega-3 FA % in RBCs (odds ratio: 0.47; 95% CI 0.24, 0.92, for a s.d. increase). Conclusion. The inverse association between anti-CCP2 positivity and self-reported omega-3 FA supplement use and omega-3 FA % in RBCs suggests that omega-3 FAs may protect against the development of RA-related autoimmunity in pre-clinical RA. PMID:26370400

Trimethoprim-sulfamethoxazole induced hyperkalaemia in elderly patients receiving spironolactone: nested case-control study

PubMed Central

Gomes, Tara; Mamdani, Muhammad M; Yao, Zhan; Hellings, Chelsea; Garg, Amit X; Weir, Matthew A; Juurlink, David N

2011-01-01

Objectives To characterise the risk of admission to hospital for hyperkalaemia in elderly patients treated with trimethoprim-sulfamethoxazole in combination with spironolactone. Design Population based nested case-control study. Setting Ontario, Canada, from 1 April 1992 to 1 March 2010. Participants Cases were residents of Ontario aged 66 years or above receiving chronic treatment with spironolactone and admitted to hospital with hyperkalaemia within 14 days of receiving a prescription for either trimethoprim-sulfamethoxazole, amoxicillin, norfloxacin, or nitrofurantoin. Up to four controls for each case were identified from the same cohort, matched on age, sex, and presence or absence of chronic kidney disease and diabetes, and required to have received one of the study antibiotics within 14 days before the case’s index date. Main outcome measures Odds ratio for association between admission to hospital with hyperkalaemia and receipt of a study antibiotic in the preceding 14 days, adjusted for conditions and drugs that may influence risk of hyperkalaemia. Results During the 18 year study period, 6903 admissions for hyperkalaemia were identified, 306 of which occurred within 14 days of antibiotic use. Of these, 248 (81%) cases were matched to 783 controls. 10.8% (17 859/165 754) of spironolactone users received at least one prescription for trimethoprim-sulfamethoxazole. Compared with amoxicillin, prescription of trimethoprim-sulfamethoxazole was associated with a marked increase in the risk of admission to hospital for hyperkalaemia (adjusted odds ratio 12.4, 95% confidence interval 7.1 to 21.6). The population attributable fraction was 59.7%, suggesting that approximately 60% of all cases of hyperkalaemia in older patients taking spironolactone and treated with an antibiotic for a urinary tract infection could be avoided if trimethoprim-sulfamethoxazole was not prescribed. Treatment with nitrofurantoin was also associated with an increase in the risk of hyperkalaemia (adjusted odds ratio 2.4, 1.3 to 4.6), but no such risk was found with norfloxacin (adjusted odds ratio 1.6, 0.8 to 3.4) Conclusions Among older patients receiving spironolactone, treatment with trimethoprim-sulfamethoxazole was associated with a major increase in the risk of admission to hospital for hyperkalaemia. This drug combination should be avoided when possible. PMID:21911446

A role for nonapeptides and dopamine in nest-building behaviour.

PubMed

Hall, Z J; Healy, S D; Meddle, S L

2015-02-01

During nest building in zebra finches (Taeniopygia guttata), several regions in the social behaviour network and the dopaminergic reward system, which are two neural circuits involved in social behaviour, appear to be active in male and female nest-building finches. Because the nonapeptides, mesotocin and vasotocin and the neurotransmitter, dopamine, play important roles in avian social behaviour, we tested the hypothesis that mesotocinergic-vasotocinergic and dopaminergic neuronal populations in the social behaviour network and dopaminergic reward system, respectively, are active during nest building. We combined immunohistochemistry for Fos (an indirect marker of neuronal activity) and vasotocin, mesotocin or tyrosine hydroxylase on brain tissue from nest-building and non-nest-building male and female zebra finches and compared Fos immunoreactivity in these neuronal populations with the variation in nest-building behaviour. Fos immunoreactivity in all three types of neuronal populations increased with some aspect of nest building: (i) higher immunoreactivity in a mesotocinergic neuronal population of nest-building finches compared to controls; (ii) increased immunoreactivity in the vasotocinergic neuronal populations in relation to the amount of material picked up by nest-building males and the length of time that a male spent in the nest with his mate; and (iii) increased immunoreactivity in a dopaminergic neuronal population in relation to the length of time that a male nest-building finch spent in the nest with his mate. Taken together, these findings provide evidence for a role of the mesotocinergic-vasotocinergic and dopaminergic systems in avian nest building. © 2014 The Authors. Journal of Neuroendocrinology published by John Wiley & Sons Ltd on behalf of British Society for Neuroendocrinology.

Seasonal productivity in a population of migratory songbirds: why nest data are not enough

USGS Publications Warehouse

Streby, Henry M.; Andersen, David E.

2011-01-01

Population models for many animals are limited by a lack of information regarding juvenile survival. In particular, studies of songbird reproductive output typically terminate with the success or failure of nests, despite the fact that adults spend the rest of the reproductive season rearing dependent fledglings. Unless fledgling survival does not vary, or varies consistently with nest productivity, conclusions about population dynamics based solely on nest data may be misleading. During 2007 and 2008, we monitored nests and used radio telemetry to monitor fledgling survival for a population of Ovenbirds (Seiurus aurocapilla) in a managed-forest landscape in north-central Minnesota, USA. In addition to estimating nest and fledgling survival, we modeled growth for population segments partitioned by proximity to edges of non-nesting cover types (regenerating clearcuts). Nest survival was significantly lower, but fledgling survival was significantly higher, in 2007 than in 2008. Despite higher nest productivity in 2008, seasonal productivity (number of young surviving to independence per breeding female) was higher in 2007. Proximity to clearcut edge did not affect nest productivity. However, fledglings from nests near regenerating sapling-dominated clearcuts (7–20 years since harvest) had higher daily survival (0.992 ± 0.005) than those from nests in interior forest (0.978 ± 0.006), which in turn had higher daily survival than fledglings from nests near shrub-dominated clearcuts (≤6 years since harvest; 0.927 ± 0.030) in 2007, with a similar but statistically non-significant trend in 2008. Our population growth models predicted growth rates that differed by 2–39% (x¯ = 25%) from simpler models in which we replaced our estimates of first-year survival with one-half adult annual survival (an estimate commonly used in songbird population growth models). We conclude that nest productivity is an inadequate measure of songbird seasonal productivity, and that results based exclusively on nest data can yield misleading conclusions about population growth and clearcut edge effects. We suggest that direct estimates of juvenile survival could provide more accurate information for the management and conservation of many animal taxa.

Infections and the risk of incident giant cell arteritis: a population-based, case-control study.

PubMed

Rhee, Rennie L; Grayson, Peter C; Merkel, Peter A; Tomasson, Gunnar

2017-06-01

Alterations in the immune system and infections are suspected to increase susceptibility to giant cell arteritis (GCA). Recently herpes zoster has been directly implicated in the pathogenesis of GCA. We examined the association between prior infections, in particular herpes zoster, and incident GCA in a population-based cohort. A nested case-control study was performed using an electronic database from the UK. Cases with newly diagnosed GCA were identified using a validated algorithm and compared with age-matched, sex-matched and practice-matched controls. Conditional logistic regression was used to examine the relationship between any infection or herpes zoster infection on the development of GCA after adjusting for potential confounders; results were expressed as incidence rate ratios (IRRs). There were 4559 cases of GCA and 22 795 controls. Any prior infection and herpes zoster were associated with incident GCA (IRR 1.26 (95% CI 1.16 to 1.36), p<0.01; and 1.17 (95% CI 1.04 to 1.32), p<0.01, respectively). A greater number of infections was associated with a higher risk of developing GCA (IRR for 1, 2-4 and ≥5 infections was 1.28, 1.60 and 2.18, respectively). Antecedent infections and, to a lesser extent, herpes zoster infections are modestly associated with incident GCA. These data provide population-level support for the hypothesis that long-standing alterations of the immune system are associated with susceptibility to GCA and suggest that herpes zoster is unlikely to play a major causal role in the pathogenesis of GCA. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Brief Report: Maternal Smoking during Pregnancy and Autism Spectrum Disorders

ERIC Educational Resources Information Center

Lee, Brian K.; Gardner, Renee M.; Dal, Henrik; Svensson, Anna; Galanti, Maria Rosaria; Rai, Dheeraj; Dalman, Christina; Magnusson, Cecilia

2012-01-01

Prenatal exposure to tobacco smoke is suggested as a potential risk factor for autism spectrum disorders (ASD). Previous epidemiological studies of this topic have yielded mixed findings. We performed a case-control study of 3,958 ASD cases and 38,983 controls nested in a large register-based cohort in Sweden. ASD case status was measured using a…

Suicide among immigrant population in Norway: a national register-based study.

PubMed

Puzo, Q; Mehlum, L; Qin, P

2017-06-01

To investigate differences in suicide risk among immigrant population in Norway compared with native Norwegians, with respect to associated country group of origin. Based on the entire national population, a nested case-control design was adopted using Norwegian national longitudinal registers to obtain 23 073 suicide cases having occurred in 1969-2012 and 373 178 controls. Odds ratios (ORs) for suicide were estimated using conditional logistic regression analysis adjusting for socio-economic factors. Compared with native Norwegians, suicide risk was significantly lower in first- and second-generation immigrants but higher in Norwegian-born with one foreign-born parent and foreign-born individuals with at least one Norwegian-born parent. When stratifying data by country group of origin, first-generation immigrants had lower ORs in most of the strata. Subjects born in Asia and in Central and South America with at least one Norwegian-born parent had a significantly higher risk of suicide. The observed results remained mostly unchanged in the analyses controlled for socio-economic status. Suicide risk is lower in first- and second-generation immigrants but higher in subjects born in Norway with one foreign-born parent and those born abroad with at least one Norwegian-born parent, with notable differences by country group of origin. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

A simple, physiologically-based model of sea turtle remigration intervals and nesting population dynamics: Effects of temperature.

PubMed

Neeman, Noga; Spotila, James R; O'Connor, Michael P

2015-09-07

Variation in the yearly number of sea turtles nesting at rookeries can interfere with population estimates and obscure real population dynamics. Previous theoretical models suggested that this variation in nesting numbers may be driven by changes in resources at the foraging grounds. We developed a physiologically-based model that uses temperatures at foraging sites to predict foraging conditions, resource accumulation, remigration probabilities, and, ultimately, nesting numbers for a stable population of sea turtles. We used this model to explore several scenarios of temperature variation at the foraging grounds, including one-year perturbations and cyclical temperature oscillations. We found that thermally driven resource variation can indeed synchronize nesting in groups of turtles, creating cohorts, but that these cohorts tend to break down over 5-10 years unless regenerated by environmental conditions. Cohorts were broken down faster at lower temperatures. One-year perturbations of low temperature had a synchronizing effect on nesting the following year, while high temperature perturbations tended to delay nesting in a less synchronized way. Cyclical temperatures lead to cyclical responses both in nesting numbers and remigration intervals, with the amplitude and lag of the response depending on the duration of the cycle. Overall, model behavior is consistent with observations at nesting beaches. Future work should focus on refining the model to fit particular nesting populations and testing further whether or not it may be used to predict observed nesting numbers and remigration intervals. Copyright © 2015 Elsevier Ltd. All rights reserved.

Association between biomass fuel and pulmonary tuberculosis: a nested case-control study.

PubMed

Kolappan, C; Subramani, R

2009-08-01

To quantify the association between biomass fuel usage and sputum-positive pulmonary tuberculosis. A tuberculosis prevalence survey was conducted in a random sample of 50 rural units (villages) and three urban units in the Tiruvallur district of Tamilnadu, India during the period 2001-2003. Additional data regarding exposure to tobacco smoking, alcohol consumption, biomass fuel usage and Standard of Living Index (SLI) were also collected from the study participants. A nested case-control study was carried out in this population. Cases are defined as bacteriological-positive cases diagnosed by either sputum smear or culture examination. For each case, five age- (within +/-5 years of age) and sex-matched controls were selected randomly from the non-cases residing in the same village/unit. Thus, 255 cases and 1275 controls were included in this study. The unadjusted OR measured from univariate analysis for biomass fuel is 2.9 (95% CI 1.8 to 4.7). The adjusted OR measured from multivariate analysis using Cox regression is 1.7 (95% CI 1.0 to 2.9). Thirty-six percent of cases are attributable to biomass fuel usage. The findings from this case-control study add to the evidence for an independent association between biomass smoke and pulmonary tuberculosis. Improvement in standards of living brought about by economic development will lead to more people using cleaner fuels for cooking than biomass fuel which in turn will lead to a reduction in the occurrence of pulmonary tuberculosis in the community.

Sarcosine and other metabolites along the choline oxidation pathway in relation to prostate cancer--a large nested case-control study within the JANUS cohort in Norway.

PubMed

de Vogel, Stefan; Ulvik, Arve; Meyer, Klaus; Ueland, Per Magne; Nygård, Ottar; Vollset, Stein Emil; Tell, Grethe S; Gregory, Jesse F; Tretli, Steinar; Bjørge, Tone

2014-01-01

Methyl group donors and intermediates of one-carbon metabolism affect DNA synthesis and DNA methylation, and may thereby affect prostate carcinogenesis. Choline, the precursor of betaine, and the one-carbon metabolite sarcosine have been associated with increased prostate cancer risk. Within JANUS, a prospective cohort in Norway (n = 317,000) with baseline serum samples, we conducted a nested case-control study among 3,000 prostate cancer cases and 3,000 controls. Using conditional logistic regression, odds ratios (ORs) and 95% confidence intervals (CIs) for prostate cancer risk were estimated according to quintiles of circulating betaine, dimethylglycine (DMG), sarcosine, glycine and serine. High sarcosine and glycine concentrations were associated with reduced prostate cancer risk of borderline significance (sarcosine: highest vs. lowest quintile OR = 0.86, CI = 0.72-1.01, p(trend) = 0.03; glycine: OR = 0.83, CI = 0.70-1.00, p(trend) = 0.07). Serum betaine, DMG and serine were not associated with prostate cancer risk. However, individuals with a high glycine/serine ratio were at decreased prostate cancer risk (OR = 0.74, CI = 0.69-0.85, p(trend) < 0.001). This population-based study suggested that men with high serum sarcosine or glycine concentrations have modestly reduced prostate cancer risk. Ratios of metabolites reflecting one-carbon balance may be associated with prostate cancer risk, as demonstrated for the glycine/serine ratio, and should be explored in future studies. © 2013 UICC.

Acute Myocardial Infarction Risk in Patients with Coronary Artery Disease Doubled after Upper Gastrointestinal Tract Bleeding: A Nationwide Nested Case-Control Study.

PubMed

Wu, Chia-Jung; Lin, Hung-Jung; Weng, Shih-Feng; Hsu, Chien-Chin; Wang, Jhi-Joung; Su, Shih-Bin; Huang, Chien-Cheng; Guo, How-Ran

2015-01-01

Prior studies of upper gastrointestinal bleeding (UGIB) and acute myocardial infarction (AMI) are small, and long-term effects of UGIB on AMI have not been delineated. We investigated whether UGIB in patients diagnosed with coronary artery disease (CAD) increased their risk of subsequent AMI. This was a population-based, nested case-control study using Taiwan's National Health Insurance Research Database. After propensity-score matching for age, gender, comorbidities, CAD date, and follow-up duration, we identified 1,677 new-onset CAD patients with AMI (AMI[+]) between 2001 and 2006 as the case group and 10,062 new-onset CAD patients without (AMI[-]) as the control group. Conditional logistic regression was used to examine the association between UGIB and AMI. Compared with UGIB[-] patients, UGIB[+] patients had twice the risk for subsequent AMI (adjusted odds ratio [AOR] = 2.08; 95% confidence interval [CI], 1.72-2.50). In the subgroup analysis for gender and age, UGIB[+] women (AOR = 2.70; 95% CI, 2.03-3.57) and patients < 65 years old (AOR = 2.23; 95% CI, 1.56-3.18) had higher odds of an AMI. UGIB[+] AMI[+] patients used nonsignificantly less aspirin than did UGIB[-] AMI[+] patients (27.69% vs. 35.61%, respectively). UGIB increased the risk of subsequent AMI in CAD patients, especially in women and patients < 65. This suggests that physicians need to use earlier and more aggressive intervention to detect UGIB and prevent AMI in CAD patients.

A Population-Based Assessment of the Drug Interaction Between Levothyroxine and Warfarin

PubMed Central

Pincus, D; Gomes, T; Hellings, C; Zheng, H; Paterson, JM; Mamdani, MM; Juurlink, DN

2013-01-01

Most drug interaction resources suggest that levothyroxine can dramatically potentiate the effect of warfarin. However, the mechanistic basis of the interaction is speculative, and little evidence supports a meaningful drug interaction. We conducted a population-based nested case–control study to examine the risk of hospitalization for hemorrhage following the initiation of levothyroxine in a cohort of 260,076 older patients receiving warfarin. In this group, we identified 10,532 case subjects hospitalized for hemorrhage and 40,595 controls. In the primary analysis, we found no association between hospitalization for hemorrhage during warfarin therapy and initiation of levothyroxine in the preceding 30 days (adjusted odds ratio 1.11, 95% confidence interval 0.67–1.86). Secondary analyses using more remote initiation of levothyroxine also found no association. These findings suggest that concerns about a clinically meaningful levothyroxine–warfarin drug interaction are not justified. Drug interaction resources that presently characterize this interaction as important should reevaluate this classification. PMID:23093318

Hospitalisation for chronic obstructive pulmonary disease and risk of suicide: a population-based case–control study

PubMed Central

Strid, Jennie Maria Christin; Christiansen, Christian Fynbo; Olsen, Morten; Qin, Ping

2014-01-01

Objectives To examine risk of suicide among individuals with hospitalised chronic obstructive pulmonary disease (COPD) and to profile differences according to sex, age, psychiatric history, and recency and frequency of COPD hospitalisations. Design Nested case–control study. Setting Data were retrieved from Danish national registries. Participants All suicide cases aged 40–95 years deceased between 1981 and 2006 in Denmark (n=19 869) and up to 20 live population controls per case matched on sex and date of birth (n=321 867 controls). Main outcome measures The relative risk of suicide associated with COPD was computed using conditional logistic regression and adjusted for effects of psychiatric history and important sociodemographic factors. Results In our study population, 3% of suicide cases had been hospitalised for COPD compared with 1% of matched population controls. Thus, a hospitalised COPD was associated with a significantly increased risk for suicide (OR 2.6; 95% CI 2.3 to 2.8). The increased risk remained significant after adjustment for psychiatric history and sociodemographic variables (OR 2.0; 95% CI 1.8 to 2.2), and increased progressively with frequency and recency of COPD hospitalisation. At the same time, suicide risk associated with COPD differed significantly by sex, age and psychiatric status. The relative risk was more pronounced in women, in individuals older than 60 years and in persons with no history of psychiatric illness. Conclusions COPD confers an important risk factor for suicide completion. Risk assessment and prevention efforts should take patients’ sex, age and psychiatric history into consideration. PMID:25421339

Freshman year mental health symptoms and level of adaptation as predictors of Internet addiction: a retrospective nested case-control study of male Chinese college students.

PubMed

Yao, Bin; Han, Wei; Zeng, Lingxia; Guo, Xiong

2013-12-15

A retrospective nested case-control study was designed to explore whether freshman year mental health status and level of adaptation are predictors of Internet addiction. The study cohort was 977 college students at a university in northwest China. In the first college year, the students' mental health status and adaptation level were assessed using the Chinese College Student Mental Health Scale (CCSMHS) and the Chinese College Student Adjustment Scale (CCSAS). In the following 1-3 years, 62 Internet-addicted subjects were identified using Young's 8-item diagnostic questionnaire. Controls were matched for demographic characteristics. Using logistic regression analysis, freshman year mental health status, including factors such as somatization, anxiety, depression and self-contempt, and freshman year adaptive problems were found to be causal factors and predictors of Internet addiction. Freshman with features of depression, learning maladaptation and dissatisfaction could be an important target-intervention population for reducing Internet addiction. © 2013 Elsevier Ireland Ltd. All rights reserved.

Index insurance for pro-poor conservation of hornbills in Thailand.

PubMed

Chantarat, Sommarat; Barrett, Christopher B; Janvilisri, Tavan; Mudsri, Sittichai; Niratisayakul, Chularat; Poonswad, Pilai

2011-08-23

This study explores the potential of index insurance as a mechanism to finance community-based biodiversity conservation in areas where a strong correlation exists between natural disaster risk, keystone species populations, and the well-being of the local population. We illustrate this potential using the case of hornbill conservation in the Budo-Sungai Padi rainforests of southern Thailand, using 16-y hornbill reproduction data and 5-y household expenditures data reflecting local economic well-being. We show that severe windstorms cause both lower household expenditures and critical nest tree losses that directly constrain nesting capacity and so reduce the number of hornbill chicks recruited in the following breeding season. Forest residents' coping strategies further disturb hornbills and their forest habitats, compounding windstorms' adverse effects on hornbills' recruitment in the following year. The strong statistical relationship between wind speed and both hornbill nest tree losses and household expenditures opens up an opportunity to design wind-based index insurance contracts that could both enhance hornbill conservation and support disaster-affected households in the region. We demonstrate how such contracts could be written and operationalized and then use simulations to show the significant promise of unique insurance-based approaches to address weather-related risk that threatens both biodiversity and poor populations.

Index insurance for pro-poor conservation of hornbills in Thailand

PubMed Central

Chantarat, Sommarat; Barrett, Christopher B.; Janvilisri, Tavan; Mudsri, Sittichai; Niratisayakul, Chularat

2011-01-01

This study explores the potential of index insurance as a mechanism to finance community-based biodiversity conservation in areas where a strong correlation exists between natural disaster risk, keystone species populations, and the well-being of the local population. We illustrate this potential using the case of hornbill conservation in the Budo-Sungai Padi rainforests of southern Thailand, using 16-y hornbill reproduction data and 5-y household expenditures data reflecting local economic well-being. We show that severe windstorms cause both lower household expenditures and critical nest tree losses that directly constrain nesting capacity and so reduce the number of hornbill chicks recruited in the following breeding season. Forest residents’ coping strategies further disturb hornbills and their forest habitats, compounding windstorms’ adverse effects on hornbills’ recruitment in the following year. The strong statistical relationship between wind speed and both hornbill nest tree losses and household expenditures opens up an opportunity to design wind-based index insurance contracts that could both enhance hornbill conservation and support disaster-affected households in the region. We demonstrate how such contracts could be written and operationalized and then use simulations to show the significant promise of unique insurance-based approaches to address weather-related risk that threatens both biodiversity and poor populations. PMID:21873183

How to save the rarest Darwin's finch from extinction: the mangrove finch on Isabela Island

PubMed Central

Fessl, Birgit; Young, Glyn H.; Young, Richard P.; Rodríguez-Matamoros, Jorge; Dvorak, Michael; Tebbich, Sabine; Fa, John E.

2010-01-01

Habitat destruction and predation by invasive alien species has led to the disappearance of several island populations of Darwin's finches but to date none of the 13 recognized species have gone extinct. However, driven by rapid economic growth in the Galápagos, the effects of introduced species have accelerated and severely threatened these iconic birds. The critically endangered mangrove finch (Camarhynchus heliobates) is now confined to three small mangroves on Isabela Island. During 2006–2009, we assessed its population status and monitored nesting success, both before and after rat poisoning. Population size was estimated at around only 100 birds for the two main breeding sites, with possibly 5–10 birds surviving at a third mangrove. Before rat control, 54 per cent of nests during incubation phase were predated with only 18 per cent of nests producing fledglings. Post-rat control, nest predation during the incubation phase fell to 30 per cent with 37 per cent of nests producing fledglings. During the nestling phase, infestation by larvae of the introduced parasitic fly (Philornis downsi) caused 14 per cent additional mortality. Using population viability analysis, we simulated the probability of population persistence under various scenarios of control and showed that with effective management of these invasive species, mangrove finch populations should start to recover. PMID:20194165

Feasibility of reusing time-matched controls in an overlapping cohort.

PubMed

Delcoigne, Bénédicte; Hagenbuch, Niels; Schelin, Maria Ec; Salim, Agus; Lindström, Linda S; Bergh, Jonas; Czene, Kamila; Reilly, Marie

2018-06-01

The methods developed for secondary analysis of nested case-control data have been illustrated only in simplified settings in a common cohort and have not found their way into biostatistical practice. This paper demonstrates the feasibility of reusing prior nested case-control data in a realistic setting where a new outcome is available in an overlapping cohort where no new controls were gathered and where all data have been anonymised. Using basic information about the background cohort and sampling criteria, the new cases and prior data are "aligned" to identify the common underlying study base. With this study base, a Kaplan-Meier table of the prior outcome extracts the risk sets required to calculate the weights to assign to the controls to remove the sampling bias. A weighted Cox regression, implemented in standard statistical software, provides unbiased hazard ratios. Using the method to compare cases of contralateral breast cancer to available controls from a prior study of metastases, we identified a multifocal tumor as a risk factor that has not been reported previously. We examine the sensitivity of the method to an imperfect weighting scheme and discuss its merits and pitfalls to provide guidance for its use in medical research studies.

Fatal motor vehicle crashes among veterans of the 1991 Gulf War and exposure to munitions demolitions at Khamisiyah: a nested case-control study.

PubMed

Gackstetter, Gary D; Hooper, Tomoko I; DeBakey, Samar F; Johnson, Amy; Nagaraj, Barbara E; Heller, Jack M; Kang, Han K

2006-04-01

A proposed explanation for the observed higher risk of fatal motor vehicle crashes (MVC) among 1991 Gulf War-deployed veterans is neurocognitive deficits resulting from nerve agent exposure at Khamisiyah, Iraq. Our objective was to assess any association between postwar fatal MVC and possible nerve agent exposure based on 2000 modeled plume data. Cases were defined as MVC deaths with a record in the Department of Transportation Fatality Analysis Reporting System through 1995. Cases (n = 282) and controls (n = 3,131) were derived from a larger nested case-control study of Gulf War-era veterans and limited to Army, male, deployed personnel. Exposure and cumulative dose by case-control status were analyzed using multivariate techniques. Exposure status was not associated with fatal MVC (OR 0.96, 95% CI 0.72-1.26), nor were tertiles of cumulative dose. Findings do not support an association between possible exposures at Khamisiyah and postwar fatal MVC among Gulf War veterans.

Recall bias in melanoma risk factors and measurement error effects: a nested case-control study within the Norwegian Women and Cancer Study.

PubMed

Parr, Christine L; Hjartåker, Anette; Laake, Petter; Lund, Eiliv; Veierød, Marit B

2009-02-01

Case-control studies of melanoma have the potential for recall bias after much public information about the relation with ultraviolet radiation. Recall bias has been investigated in few studies and only for some risk factors. A nested case-control study of recall bias was conducted in 2004 within the Norwegian Women and Cancer Study: 208 melanoma cases and 2,080 matched controls were invited. Data were analyzed for 162 cases (response, 78%) and 1,242 controls (response, 77%). Questionnaire responses to several host factors and ultraviolet exposures collected at enrollment in 1991-1997 and in 2004 were compared stratified on case-control status. Shifts in responses were observed among both cases and controls, but a shift in cases was observed only for skin color after chronic sun exposure, and a larger shift in cases was observed for nevi. Weighted kappa was lower for cases than for controls for most age intervals of sunburn, sunbathing vacations, and solarium use. Differences in odds ratio estimates of melanoma based on prospective and retrospective measurements indicate measurement error that is difficult to characterize. The authors conclude that indications of recall bias were found in this sample of Norwegian women, but that the results were inconsistent for the different exposures.

Molecular genetic status of Aleutian Canada Geese from Buldir and the Semidi Islands, Alaska

USGS Publications Warehouse

Pierson, Barbara J.; Pearce, John M.; Talbot, Sandra L.; Shields, Gerald F.; Scribner, Kim T.

2000-01-01

We conducted genetic analyses of Aleutian Canada Geese (Branta canadensis leucopareia) from Buldir Island in the western Aleutians and the Semidi Islands in the eastern portion of their breeding range. We compared data from seven microsatellite DNA loci and 143 base pairs of the control region of mitochondrial DNA from the two populations of Aleutian Canada Geese and another small-bodied subspecies, the Cackling Canada Goose (B. c. minima) which nests in western Alaska. The widely separated island-nesting Aleutian geese were genetically more closely related to each other than to mainland-nesting small-bodied geese. The populations of Aleutian geese were genetically differentiated from one another in terms of mitochondrial DNA haplotype and microsatellite allele frequencies, suggesting limited contemporary gene flow and/or major shifts in gene frequency through genetic drift. The degree of population genetic differentiation suggests that Aleutian Canada Goose populations could be considered separate management units. There was some evidence of population bottlenecks, although we found no significant genetic evidence of non-random mating or inbreeding.

Presence of Rhodnius ecuadoriensis in sylvatic habitats in the southern highlands (Loja Province) of Ecuador.

PubMed

Grijalva, M J; Villacis, A G

2009-05-01

The main vectors of Chagas disease in Ecuador are Triatoma dimidiata and Rhodnius ecuadoriensis. The latter species occupies domestic and peridomestic habitats, as well as sylvatic ecotopes--particularly associated with Phytelephas aequatorialis palm trees--in the western coastal region of Ecuador. In the southern highlands, however, such palm tree habitats are uncommon, and sylvatic populations of R. ecuadoriensis have not previously been reported to date. This study was carried out in five rural communities in Loja Province in southern Ecuador, where manual triatomine searches were conducted in various sylvatic habitats. A total of 81 squirrel nests (Sciurus stramineus) and > 200 bird nests and other habitats were searched. One hundred three R. ecuadoriensis individuals were found in 11 squirrel nests (infestation index = 13.6%, density = 2 bugs per nest searched, crowding = 9.5 bugs per infested nest, colonization index = 72.7% of infested nests with nymphs). No triatomines were found in bird nests or other sylvatic habitats. The presence of sylvatic R. ecuadoriensis in the southern highlands of Ecuador has important implications for the long-term control of Chagas disease in the region because of the possibility of reinfestation of dwellings after insecticide-based control interventions.

Air Pollution and Pulmonary Tuberculosis: A Nested Case-Control Study among Members of a Northern California Health Plan.

PubMed

Smith, Geneé S; Van Den Eeden, Stephen K; Garcia, Cynthia; Shan, Jun; Baxter, Roger; Herring, Amy H; Richardson, David B; Van Rie, Annelies; Emch, Michael; Gammon, Marilie D

2016-06-01

Ecologic analyses, case-case comparisons, and animal experiments suggest positive associations between air pollution and tuberculosis. We evaluated this hypothesis in a large sample, which yielded results that are applicable to the general population. We conducted a case-control study nested within a cohort of Kaiser Permanente of Northern California members. All active pulmonary tuberculosis (TB) cases newly diagnosed between 1996 and 2010 (n = 2,309) were matched to two controls (n = 4,604) by age, sex, and race/ethnicity on the index date corresponding with the case diagnosis date. Average individual-level concentrations of carbon monoxide (CO), nitrogen dioxide (NO2), sulfur dioxide (SO2), ozone (O3), and particulate matter with aerodynamic diameter ≤ 2.5 μm (PM2.5) and 10 μm (PM10) for 2 years before diagnosis/entry into the study were estimated using measurements from the California Air Resources Board monitor closest to the participant's residence. In single-pollutant adjusted conditional logistic regression models, the pulmonary TB odds ratios (95% confidence intervals) for the highest quintile (vs. lowest) were 1.50 (95% CI: 1.15, 1.95) for CO and 1.42 (95% CI: 1.10, 1.84) for NO2. Corresponding estimates were higher among never [1.68 (95% CI: 1.26, 2.24)] than ever [1.19 (95% CI: 0.74, 1.92)] smokers for CO. In contrast, for NO2, estimates were higher among ever [1.81 (95% CI: 1.13, 2.91)] than never [1.29 (95% CI: 0.97, 1.71)] smokers. O3 was inversely associated for smokers [0.66 (95% CI: 0.43, 1.02)] and never smokers [0.65 (95% CI: 0.52, 0.81)]. No other consistent patterns were observed. In this first, to our knowledge, U.S. nested case-control study on air pollution and pulmonary TB, we observed positive associations with ambient CO and NO2, which require confirmation. Smith GS, Van Den Eeden SK, Garcia C, Shan J, Baxter R, Herring AH, Richardson DB, Van Rie A, Emch M, Gammon MD. 2016. Air pollution and pulmonary tuberculosis: a nested case-control study among members of a Northern California health plan. Environ Health Perspect 124:761-768; http://dx.doi.org/10.1289/ehp.1408166.

Helicobacter pylori infection, chronic corpus atrophic gastritis and pancreatic cancer risk in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort: A nested case-control study.

PubMed

Huang, Jiaqi; Zagai, Ulrika; Hallmans, Göran; Nyrén, Olof; Engstrand, Lars; Stolzenberg-Solomon, Rachael; Duell, Eric J; Overvad, Kim; Katzke, Verena A; Kaaks, Rudolf; Jenab, Mazda; Park, Jin Young; Murillo, Raul; Trichopoulou, Antonia; Lagiou, Pagona; Bamia, Christina; Bradbury, Kathryn E; Riboli, Elio; Aune, Dagfinn; Tsilidis, Konstantinos K; Capellá, Gabriel; Agudo, Antonio; Krogh, Vittorio; Palli, Domenico; Panico, Salvatore; Weiderpass, Elisabete; Tjønneland, Anne; Olsen, Anja; Martínez, Begoña; Redondo-Sanchez, Daniel; Chirlaque, Maria-Dolores; Hm Peeters, Petra; Regnér, Sara; Lindkvist, Björn; Naccarati, Alessio; Ardanaz, Eva; Larrañaga, Nerea; Boutron-Ruault, Marie-Christine; Rebours, Vinciane; Barré, Amélie; Bueno-de-Mesquita, H B As; Ye, Weimin

2017-04-15

The association between H. pylori infection and pancreatic cancer risk remains controversial. We conducted a nested case-control study with 448 pancreatic cancer cases and their individually matched control subjects, based on the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort, to determine whether there was an altered pancreatic cancer risk associated with H. pylori infection and chronic corpus atrophic gastritis. Conditional logistic regression models were applied to calculate odds ratios (ORs) and corresponding 95% confidence intervals (CIs), adjusted for matching factors and other potential confounders. Our results showed that pancreatic cancer risk was neither associated with H. pylori seropositivity (OR = 0.96; 95% CI: 0.70, 1.31) nor CagA seropositivity (OR = 1.07; 95% CI: 0.77, 1.48). We also did not find any excess risk among individuals seropositive for H. pylori but seronegative for CagA, compared with the group seronegative for both antibodies (OR = 0.94; 95% CI: 0.63, 1.38). However, we found that chronic corpus atrophic gastritis was non-significantly associated with an increased pancreatic cancer risk (OR = 1.35; 95% CI: 0.77, 2.37), and although based on small numbers, the excess risk was particularly marked among individuals seronegative for both H. pylori and CagA (OR = 5.66; 95% CI: 1.59, 20.19, p value for interaction < 0.01). Our findings provided evidence supporting the null association between H. pylori infection and pancreatic cancer risk in western European populations. However, the suggested association between chronic corpus atrophic gastritis and pancreatic cancer risk warrants independent verification in future studies, and, if confirmed, further studies on the underlying mechanisms. © 2016 UICC.

Prenatal and Perinatal Morbidity in Children with Tic Disorders: A Mainstream School-based Population Study in Central Spain

PubMed Central

Cubo, Esther; Hortigüela, Montesclaros; Jorge-Roldan, Sandra; Ciciliani, Selva Esther; Lopez, Patricia; Velasco, Leticia; Sastre, Emilio; Ausin, Vanesa; Delgado, Vanesa; Saez, Sara; Gabriel-Galán, José Trejo; Macarrón, Jesús

2014-01-01

Background While current research suggests that genetic factors confer the greatest risk for the development of tic disorders, studies of environmental factors are relatively few, with a lack of consistent risk factors across studies. Our aim is to analyze the association of tic disorders with exposure to prenatal and perinatal morbidity. Methods This was a nested case–control study design. Cases and controls were selected and identified from a mainstream, school-based sample. The diagnosis of tic disorders was assigned by a movement disorder neurologist using ‘Diagnostic and statistical manual of mental disorders, 4th edition, text revision’ criteria, and neuropsychiatric comorbidities were screened using the Spanish computerized version of the Diagnostic Interview Schedule for Children Predictive Scale. Information regarding the exposure to pre-perinatal risk factors was collected by a retrospective review of the birth certificates. Logistic regression analyses were then performed to test the association of tic disorders with pre-perinatal risk factors. Results Out of 407 participants, complete pre-perinatal data were available in 153 children (64 with tics and 89 without tics). After adjusting for family history of tics, neonatal respiratory distress syndrome, body mass index, prenatal infection, and coexisting comorbid neuropsychiatric disturbances, tic disorders were associated with prenatal exposure to tobacco (odds ratio [OR] = 3.07, 95% confidence interval [CI] 1.24–7.60, p = 0.007), and cesarean section (OR = 5.78, 95% CI 1.60–20.91, p = 0.01). Discussion This nested case–control study of children with tic disorders demonstrates higher adjusted odds for tics in children with exposure to cesarean delivery and maternal smoking. Longitudinal, population-based samples are required to confirm these results. PMID:25562036

Plasma carotenoids, retinol, and tocopherols and postmenopausal breast cancer risk in the Multiethnic Cohort Study: a nested case-control study

PubMed Central

Epplein, Meira; Shvetsov, Yurii B; Wilkens, Lynne R; Franke, Adrian A; Cooney, Robert V; Le Marchand, Loïc; Henderson, Brian E; Kolonel, Laurence N; Goodman, Marc T

2009-01-01

Introduction Assessments by the handful of prospective studies of the association of serum antioxidants and breast cancer risk have yielded inconsistent results. This multiethnic nested case-control study sought to examine the association of plasma carotenoids, retinol, and tocopherols with postmenopausal breast cancer risk. Methods From the biospecimen subcohort of the Multiethnic Cohort Study, 286 incident postmenopausal breast cancer cases were matched to 535 controls on age, sex, ethnicity, study location (Hawaii or California), smoking status, date/time of collection and hours of fasting. We measured prediagnostic circulating levels of individual carotenoids, retinol, and tocopherols. Conditional logistic regression was used to compute odds ratios and 95% confidence intervals. Results Women with breast cancer tended to have lower levels of plasma carotenoids and tocopherols than matched controls, but the differences were not large or statistically significant and the trends were not monotonic. No association was seen with retinol. A sensitivity analysis excluding cases diagnosed within 1 year after blood draw did not alter the findings. Conclusions The lack of significant associations in this multiethnic population is consistent with previously observed results from less racially-diverse cohorts and serves as further evidence against a causal link between plasma micronutrient concentrations and postmenopausal breast cancer risk. PMID:19619335

Breeding biology and success of a reintroduced population of the critically endangered Puaiohi (Myadestes palmeri)

USGS Publications Warehouse

Tweed, E.J.; Foster, J.T.; Woodworth, B.L.; Monahan, W.B.; Kellerman, J.L.; Lieberman, A.

2006-01-01

The ultimate success of reintroduction programs for endangered species depends on the ability of reintroduced animals to breed in the wild. We studied the nesting success and breeding biology of a reintroduced population of Puaiohi (Myadestes palmeri) on the island of Kaua'i, Hawaii. Thirty-four captive-bred Puaiohi were released into the Alaka'i Swamp in 1999-2001 and monitored using radiotelemetry. Ten females and two males paired with wild and other released birds, including one polygynous trio. From March to September, 31 nests were built. Mean clutch size was 2.0 eggs, daily nest survival was 0.97 ± 0.01 (mean ± SE) and overall nest success was 0.40 ± 0.02. We confirmed predation, most probably by rats (Rattus spp.), as the greatest cause of nest failure, occurring at 38% of active nests with known fates, and causing the death of two nesting adult females. Ground-based rodent control proved ineffective at protecting nest attempts. Successful nests fledged an average of 1.4 young each (n = 10), and 85% of fledglings survived at least two weeks. Importantly, breeding behavior and success were comparable to those of wild Puaiohi. This is the first record of breeding in the wild from captive-bred endangered Hawaiian passerines. The ability of captive-bred Puaiohi to survive and breed successfully in the wild bodes well for future releases of this and other endangered passerines, but high predation rates on nests and nesting females highlights the importance of maintaining and restoring safe habitat for recovery.

Mercury exposure and risk of cardiovascular disease: a nested case-control study in the PREDIMED (PREvention with MEDiterranean Diet) study.

PubMed

Downer, Mary K; Martínez-González, Miguel A; Gea, Alfredo; Stampfer, Meir; Warnberg, Julia; Ruiz-Canela, Miguel; Salas-Salvadó, Jordi; Corella, Dolores; Ros, Emilio; Fitó, Montse; Estruch, Ramon; Arós, Fernando; Fiol, Miquel; Lapetra, José; Serra-Majem, Lluís; Bullo, Monica; Sorli, Jose V; Muñoz, Miguel A; García-Rodriguez, Antonio; Gutierrez-Bedmar, Mario; Gómez-Gracia, Enrique

2017-01-05

Substantial evidence suggests that consuming 1-2 servings of fish per week, particularly oily fish (e.g., salmon, herring, sardines) is beneficial for cardiovascular health due to its high n-3 polyunsaturated fatty acid content. However, there is some concern that the mercury content in fish may increase cardiovascular disease risk, but this relationship remains unclear. The PREDIMED trial included 7477 participants who were at high risk for cardiovascular disease at baseline. In this study, we evaluated associations between mercury exposure, fish consumption and cardiovascular disease. We randomly selected 147 of the 288 cases diagnosed with cardiovascular disease during follow-up and matched them on age and sex to 267 controls. Instrumental neutron activation analysis was used to assess toenail mercury concentration. In-person interviews, medical record reviews and validated questionnaires were used to assess fish consumption and other covariates. Information was collected at baseline and updated yearly during follow-up. We used conditional logistic regression to evaluate associations in the total nested case-control study, and unconditional logistic regression for population subsets. Mean (±SD) toenail mercury concentrations (μg per gram) did not significantly differ between cases (0.63 (±0.53)) and controls (0.67 (±0.49)). Mercury concentration was not associated with cardiovascular disease in any analysis, and neither was fish consumption or n-3 fatty acids. The fully-adjusted relative risks for the highest versus lowest quartile of mercury concentration were 0.71 (95% Confidence Interval [CI], 0.34, 1.14; p trend  = 0.37) for the nested case-control study, 0.74 (95% CI, 0.32, 1.76; p trend  = 0.43) within the Mediterranean diet intervention group, and 0.50 (95% CI, 0.13, 1.96; p trend  = 0.41) within the control arm of the trial. Associations remained null when mercury was jointly assessed with fish consumption at baseline and during follow-up. Results were similar in different sensitivity analyses. We found no evidence that mercury exposure from regular fish consumption increases cardiovascular disease risk in a population of Spanish adults with high cardiovascular disease risk and high fish consumption. This implies that the mercury content in fish does not detract from the already established cardiovascular benefits of fish consumption. ISRCTN35739639 .

Investigation of established genetic risk variants for glioma in prediagnostic samples from a population-based nested case-control study.

PubMed

Wibom, Carl; Späth, Florentin; Dahlin, Anna M; Langseth, Hilde; Hovig, Eivind; Rajaraman, Preetha; Johannesen, Tom Børge; Andersson, Ulrika; Melin, Beatrice

2015-05-01

Although glioma etiology is poorly understood in general, growing evidence indicates a genetic component. Four large genome-wide association studies (GWAS) have linked common genetic variants with an increased glioma risk. However, to date, these studies are based largely on a case-control design, where cases have been recruited at the time of or after diagnosis. They may therefore suffer from a degree of survival bias, introduced when rapidly fatal cases are not included. To confirm glioma risk variants in a prospective setting, we have analyzed 11 previously identified risk variants in a set of prediagnostic serum samples with 598 cases and 595 matched controls. Serum samples were acquired from The Janus Serum Bank, a Norwegian population-based biobank reserved for cancer research. We confirmed the association with glioma risk for variants within five genomic regions: 8q24.21 (CCDC26), 9p21.3 (CDKN2B-AS1), 11q23.3 (PHLDB1), 17p13.1 (TP53), and 20q13.33 (RTEL1). However, previously identified risk variants within the 7p11.2 (EGFR) region were not confirmed by this study. Our results indicate that the risk variants that were confirmed by this study are truly associated with glioma risk and may, consequently, affect gliomagenesis. Though the lack of positive confirmation of EGFR risk variants may be attributable to relatively limited statistical power, it nevertheless raises the question whether they truly are risk variants or markers for glioma prognosis. Our findings indicate the need for further studies to clarify the role of glioma risk loci with respect to prolonged survival versus etiology. ©2015 American Association for Cancer Research.

A population-based nested case control study on recurrent pneumonias in children with severe generalized cerebral palsy: ethical considerations of the design and representativeness of the study sample.

PubMed

Veugelers, Rebekka; Calis, Elsbeth A C; Penning, Corine; Verhagen, Arianne; Bernsen, Roos; Bouquet, Jan; Benninga, Marc A; Merkus, Peter J F M; Arets, Hubertus G M; Tibboel, Dick; Evenhuis, Heleen M

2005-07-19

In children with severe generalized cerebral palsy, pneumonias are a major health issue. Malnutrition, dysphagia, gastro-oesophageal reflux, impaired respiratory function and constipation are hypothesized risk factors. Still, no data are available on the relative contribution of these possible risk factors in the described population. This paper describes the initiation of a study in 194 children with severe generalized cerebral palsy, on the prevalence and on the impact of these hypothesized risk factors of recurrent pneumonias. A nested case-control design with 18 months follow-up was chosen. Dysphagia, respiratory function and constipation will be assessed at baseline, malnutrition and gastro-oesophageal reflux at the end of the follow-up. The study population consists of a representative population sample of children with severe generalized cerebral palsy. Inclusion was done through care-centres in a predefined geographical area and not through hospitals. All measurements will be done on-site which sets high demands on all measurements. If these demands were not met in "gold standard" methods, other methods were chosen. Although the inclusion period was prolonged, the desired sample size of 300 children was not met. With a consent rate of 33%, nearly 10% of all eligible children in The Netherlands are included (n = 194). The study population is subtly different from the non-participants with regard to severity of dysphagia and prevalence rates of pneumonias and gastro-oesophageal reflux. Ethical issues complicated the study design. Assessment of malnutrition and gastro-oesophageal reflux at baseline was considered unethical, since these conditions can be easily treated. Therefore, we postponed these diagnostics until the end of the follow-up. In order to include a representative sample, all eligible children in a predefined geographical area had to be contacted. To increase the consent rate, on-site measurements are of first choice, but timely inclusion is jeopardized. The initiation of this first study among children with severe neurological impairment led to specific, unexpected problems. Despite small differences between participants and non-participating children, our sample is as representative as can be expected from any population-based study and will provide important, new information to bring us further towards effective interventions to prevent pneumonias in this population.

Self-reported Ethnicity, Genetic Structure and the Impact of Population Stratification in a Multiethnic Study

PubMed Central

Wang, Hansong; Haiman, Christopher A.; Kolonel, Laurence N.; Henderson, Brian E.; Wilkens, Lynne R.; Le Marchand, Loïc; Stram, Daniel O.

2011-01-01

It is well-known that population substructure may lead to confounding in case-control association studies. Here, we examined genetic structure in a large racially and ethnically diverse sample consisting of 5 ethnic groups of the Multiethnic Cohort study (African Americans, Japanese Americans, Latinos, European Americans and Native Hawaiians) using 2,509 SNPs distributed across the genome. Principal component analysis on 6,213 study participants, 18 Native Americans and 11 HapMap III populations revealed 4 important principal components (PCs): the first two separated Asians, Europeans and Africans, and the third and fourth corresponded to Native American and Native Hawaiian (Polynesian) ancestry, respectively. Individual ethnic composition derived from self-reported parental information matched well to genetic ancestry for Japanese and European Americans. STRUCTURE-estimated individual ancestral proportions for African Americans and Latinos are consistent with previous reports. We quantified the East Asian (mean 27%), European (mean 27%) and Polynesian (mean 46%) ancestral proportions for the first time, to our knowledge, for Native Hawaiians. Simulations based on realistic settings of case-control studies nested in the Multiethnic Cohort found that the effect of population stratification was modest and readily corrected by adjusting for race/ethnicity or by adjusting for top PCs derived from all SNPs or from ancestry informative markers; the power of these approaches was similar when averaged across causal variants simulated based on allele frequencies of the 2,509 genotyped markers. The bias may be large in case-only analysis of gene by gene interactions but it can be corrected by top PCs derived from all SNPs. PMID:20499252

Smoking, obesity and risk of sarcoidosis: A population-based nested case-control study.

PubMed

Ungprasert, Patompong; Crowson, Cynthia S; Matteson, Eric L

2016-11-01

Smoking and obesity might alter the risk of sarcoidosis. However, the data remained inconclusive. A cohort of Olmsted County, Minnesota residents diagnosed with sarcoidosis between January 1, 1976 and December 31, 2013 was identified based on individual medical record review. For each sarcoidosis subject, one sex and aged-matched control without sarcoidosis was randomly selected from the same underlying population. Medical records of cases and controls were reviewed for smoking status at index date and body mass index (BMI) within 1 year before to 3 months after index date. 345 incident cases of sarcoidosis and 345 controls were identified. The odds ratio of sarcoidosis comparing current smokers with never smokers adjusted for age and sex was 0.34 (95% confidence interval (CI), 0.23-0.50). The odds ratio of sarcoidosis comparing current smokers with never smokers and former smokers adjusted for age and sex was 0.38 (95% CI, 0.26-0.56). The odds ratio of sarcoidosis comparing overweight subjects (BMI ≥ 25 kg/m 2 but < 30 kg/m 2 ) with subjects with normal/low BMI was 1.12 (95% CI, 0.72-1.75). The odds ratio of sarcoidosis comparing obese subjects (BMI ≥ 30 kg/m 2 ) with subjects with normal/low BMI was 2.54 (95% CI, 1.58-4.06). The odds ratio of sarcoidosis comparing obese subjects with non-obese subjects was 2.38 (95% CI, 1.60-3.56). In this population, current smokers have a lower risk of developing sarcoidosis while subjects with obesity have a higher risk of developing sarcoidosis. Copyright © 2016 Elsevier Ltd. All rights reserved.

Neuroepidemiologic Case Definition of Gulf War Illness from Neuroimaging and EEG in a Population-Representative Nested Case-Control Sample of Gulf War Veterans

DTIC Science & Technology

2017-10-01

PROJECT NUMBER 5e. TASK NUMBER E-Mail: 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) AND ADDRESS(ES) 8. PERFORMING... ORGANIZATION REPORT NUMBER 9. SPONSORING / MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSOR/MONITOR’S ACRONYM(S) U.S. Army Medical Research and...Participants & Other Collaborating Organizations 13 8. Special Reporting Requirements 14 9. Appendices 14 4 1. INTRODUCTION: 2. KEYWORDS

Perinatal factors and the risk of bipolar disorder in Finland.

PubMed

Chudal, Roshan; Sourander, Andre; Polo-Kantola, Päivi; Hinkka-Yli-Salomäki, Susanna; Lehti, Venla; Sucksdorff, Dan; Gissler, Mika; Brown, Alan S

2014-02-01

Complications during the perinatal period have been associated with neurodevelopmental disorders like schizophrenia and autism. However, similar studies on bipolar disorder (BPD) have been limited and the findings are inconsistent. The aim of this study was to examine the association between perinatal risk factors and BPD. This nested case-control study, based on the Finnish Prenatal Study of Bipolar Disorders (FIPS-B), identified 724 cases and 1419 matched controls from population based registers. Conditional logistic regression was used to examine the associations between perinatal factors and BPD adjusting for potential confounding due to maternal age, psychiatric history and educational level, place of birth, number of previous births and maternal smoking during pregnancy. Children delivered by planned cesarean section had a 2.5-fold increased risk of BPD (95% CI: 1.32-4.78, P<0.01). No association was seen between other examined perinatal risk factors and BPD. The limitations of this study include: the restriction in the sample to treated cases of BPD in the population, and usage of hospital based clinical diagnosis for case ascertainment. In addition, in spite of the large sample size, there was low power to detect associations for certain exposures including the lowest birth weight category and pre-term birth. Birth by planned cesarean section was associated with risk of BPD, but most other perinatal risk factors examined in this study were not associated with BPD. Larger studies with greater statistical power to detect less common exposures and studies utilizing prospective biomarker-based exposures are necessary in the future. © 2013 Published by Elsevier B.V.

Somatoform disorder as a predictor of interstitial cystitis/bladder pain syndrome: Evidence from a nested case-control study and a retrospective cohort study.

PubMed

Chen, I-Chun; Lee, Ming-Huei; Lin, Hsuan-Hung; Wu, Shang-Liang; Chang, Kun-Min; Lin, Hsiu-Ying

2017-05-01

Interstitial cystitis/bladder pain syndrome (IC/BPS) has several well-known comorbid psychiatric manifestations, including insomnia, anxiety, and depression. We hypothesized that somatoform disorder, which is a psychosomatic disease, can be used as a sensitive psychiatric phenotype of IC/BPS. We investigated whether somatoform disorder increases the risk of IC/BPS.A nested case-control study and a retrospective cohort study were followed up over a 12-year period (2002-2013) in the Taiwan Health Insurance Reimbursement Database. In the nested case-control study, 1612 patients with IC/BPS were matched in a 1:2 ratio to 3224 controls based on propensity scores. The odds ratio for somatoform disorder was calculated using conditional logistic regression analysis. In the retrospective cohort study, 1436 patients with somatoform disorder were matched in a 1:2 ratio to 2872 patients with nonsomatoform disorder based on propensity scores. Cox regression analysis was used to estimate the hazard ratio associated with the development of IC/BPS in patients with somatoform disorder, and the cumulative survival probability was tested using the Kaplan-Meier analysis.We found that the odds ratio for somatoform disorder was 2.46 (95% confidence interval [CI], 1.05-5.76). Although the average time until IC/BPS development in the control subjects was 11.5 ± 1.3 years, this interval was shorter in patients with somatoform disorder (6.3 ± 3.6 years). The hazard ratio for developing IC/BPS was 2.50 (95% CI 1.23-5.58); the adjusted hazard ratio was 2.26 (95% CI 1.002-5.007). The patients and controls also differed significantly in their cumulative survival probability for IC/BPS (log rank P < .05).Evidence from the nested case-control study and retrospective cohort study consistently indicated that somatoform disorder increases the risk for IC/BPS. Our study suggests that somatoform disorder can be used as a sensitive psychiatric phenotype to predict IC/BPS. Any past history of somatoform disorder should be documented while examining patients with IC/BPS.

Risk factors for breast cancer in a cohort of mammographic screening program: a nested case-control study within the FRiCaM study.

PubMed

Bravi, Francesca; Decarli, Adriano; Russo, Antonio Giampiero

2018-05-01

Breast cancer is the most common cancer diagnosis and the leading cause of cancer death among women in the world, and differences across populations indicate a role of hormonal, reproductive and lifestyle factors. This study is based on a cohort of 78,050 women invited to undergo a mammogram by Local Health Authority of Milan, between 2003 and 2007. We carried out a nested case-control study including all the 3303 incident breast cancer cases diagnosed up to 2015, and 9909 controls matched by age and year of enrollment. Odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were estimated using logistic regression models. The ORs were 0.88 (95% CI: 0.78-0.98) for an age at menarche ≥14 years and 1.39 (95% CI: 1.07-1.81) for an age of 30 years or older at first pregnancy. Body mass index (BMI) was positively associated with breast cancer risk in women older than 50 years (OR = 1.89, 95% CI: 1.54-2.31, for BMI≥30 vs. <20), while the association tended to be inverse in younger women. A high mammographic density increased breast cancer risk (OR = 2.61, 95% CI: 2.02-3.38 for density >75% vs. adipose tissue). The ORs were 1.67 (95% CI: 1.47-1.89) and 2.04 (95% CI: 1.38-3.00) for one first-degree relative and two or more relatives affected by breast cancer, respectively. Our study confirms the role of major recognized risk factors for breast cancer in our population and provides the basis for a stratification of the participants in the mammographic screening according to different levels of risk. © 2018 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

Risk of bleeding and antibiotic use in patients receiving continuous phenprocoumon therapy. A case-control study nested in a large insurance- and population-based German cohort.

PubMed

Abbas, Sascha; Ihle, Peter; Harder, Sebastian; Schubert, Ingrid

2014-05-05

There is major concern about coumarins interacting with various drug classes and increasing the risk of overanticoagulation. The aim of the study was to assess bleeding risk in patients with concurrent use of antibiotics and phenprocoumon, the most widely prescribed coumarin in many European countries. We conducted a nested-case-control study within a cohort of 513,338 incident and continuous phenprocoumon users ≥ 18 years of age using claims data of the statutory health insurance company AOK, covering 30% of the German population. Bleeding risk associated with current use of antibiotics for systemic use (antibacterials/antimycotics) was calculated using conditional logistic regression in 13,785 cases with a bleeding event and 55,140 risk-set sampling-matched controls. Bleeding risk associated with any antibacterial use in phenprocoumon users was significantly increased [odds ratio (OR) 2.37, 95% confidence interval (CI) 2.20-2.56]. The association was stronger for gastrointestinal than for cerebral bleeding (OR 2.09, 95% CI 1.84-2.38 and OR 1.34, 95% CI 1.03-1.74, respectively) and highest for other/unspecified bleeding (OR 2.92, 95% CI 2.62-3.26). Specific antibiotic classes were strongly associated with bleeding risk, e.g. cotrimoxazole (OR 3.86, 95% CI 3.08-4.84) and fluorquinolones (OR 3.13, 95% CI 2.74-3.59), among those highest for ofloxacin (OR 5.00, 95% CI 3.01-8.32). Combined use of phenprocoumon and antimycotics was not significantly associated with bleeding risk. Risk was not significantly modified by age (pint=0.25) or sex (pint=0.96). The association was stronger the closer the antibiotic exposure was to the bleeding event. Among continuous phenprocoumon users, antibiotics - particularly quinolones and cotrimoxazole - should be prescribed after careful consideration due to an increased bleeding risk. Close monitoring of international normalised ratio levels after prescription is recommended.

Acute Myocardial Infarction Risk in Patients with Coronary Artery Disease Doubled after Upper Gastrointestinal Tract Bleeding: A Nationwide Nested Case-Control Study

PubMed Central

Weng, Shih-Feng; Hsu, Chien-Chin; Wang, Jhi-Joung; Su, Shih-Bin; Huang, Chien-Cheng; Guo, How-Ran

2015-01-01

Prior studies of upper gastrointestinal bleeding (UGIB) and acute myocardial infarction (AMI) are small, and long-term effects of UGIB on AMI have not been delineated. We investigated whether UGIB in patients diagnosed with coronary artery disease (CAD) increased their risk of subsequent AMI. This was a population-based, nested case-control study using Taiwan’s National Health Insurance Research Database. After propensity-score matching for age, gender, comorbidities, CAD date, and follow-up duration, we identified 1,677 new-onset CAD patients with AMI (AMI[+]) between 2001 and 2006 as the case group and 10,062 new-onset CAD patients without (AMI[−]) as the control group. Conditional logistic regression was used to examine the association between UGIB and AMI. Compared with UGIB[−] patients, UGIB[+] patients had twice the risk for subsequent AMI (adjusted odds ratio [AOR] = 2.08; 95% confidence interval [CI], 1.72–2.50). In the subgroup analysis for gender and age, UGIB[+] women (AOR = 2.70; 95% CI, 2.03–3.57) and patients < 65 years old (AOR = 2.23; 95% CI, 1.56–3.18) had higher odds of an AMI. UGIB[+] AMI[+] patients used nonsignificantly less aspirin than did UGIB[−] AMI[+] patients (27.69% vs. 35.61%, respectively). UGIB increased the risk of subsequent AMI in CAD patients, especially in women and patients < 65. This suggests that physicians need to use earlier and more aggressive intervention to detect UGIB and prevent AMI in CAD patients. PMID:26529110

Bait distribution among multiple colonies of Pharaoh ants (hymenoptera: Formicidae).

PubMed

Oi, D H; Vail, K M; Williams, D F

2000-08-01

Pharaoh ant, Monomorium pharaonis (L.), infestations often consist of several colonies located at different nest sites. To achieve control, it is desirable to suppress or eliminate the populations of a majority of these colonies. We compared the trophallactic distribution and efficacy of two ant baits, with different modes of action, among groups of four colonies of Pharaoh ants. Baits contained either the metabolic-inhibiting active ingredient hydramethylnon or the insect growth regulator (IGR) pyriproxyfen. Within 3 wk, the hydramethylnon bait reduced worker and brood populations by at least 80%, and queen reductions ranged between 73 and 100%, when nests were in proximity (within 132 cm) to the bait source. However, these nest sites were reoccupied by ants from other colonies located further from the bait source. The pyriproxyfen bait was distributed more thoroughly to all nest locations with worker populations gradually declining by 73% at all nest sites after 8 wk. Average queen reductions ranged from 31 to 49% for all nest sites throughout the study. Even though some queens survived, brood reductions were rapid in the pyriproxyfen treatment, with reductions of 95% at all locations by week 3. Unlike the metabolic inhibitor, the IGR did not kill adult worker ants quickly, thus, more surviving worker ants were available to distribute the bait to all colonies located at different nest sites. Thus, from a single bait source, the slow-acting bait toxicant provided gradual, but long-term control, whereas the fast-acting bait toxicant provided rapid, localized control for a shorter duration.

Serum levels of C-reactive protein in adolescents with periodontitis.

PubMed

López, Rodrigo; Baelum, Vibeke; Hedegaard, Chris Juul; Bendtzen, Klaus

2011-04-01

The results of several cross-sectional studies suggested a relationship between periodontitis and higher serum levels of C-reactive protein (CRP). Most of these studies were restricted to adult study groups with severe periodontal inflammation, and the potential effects of confounding factors were frequently overlooked. A case-referent study comprised of 87 adolescent cases who presented with clinical attachment loss ≥3 mm recorded in ≥2 of 16 teeth and 73 controls who did not fulfill these criteria was nested in a fully enumerated adolescent population. Venous blood samples were obtained, and CRP levels were quantified, using a high-sensitive bead-based flow cytometric assay. The Mann-Whitney U test was used to assess overall differences between groups. The median serum CRP values for cases and controls were 64 ng/ml (interquartile range: 27 to 234 ng/ml) and 55 ng/ml (31 to 183 ng/ml), respectively (P = 0.8). Serum levels of CRP were not significantly higher among subjects with periodontitis than among controls. However, a statistically significant positive association between percentages of sites with bleeding on probing and log-transformed CRP values was observed.

SOS1 gene polymorphisms are associated with gestational diabetes mellitus in a Chinese population: Results from a nested case-control study in Taiyuan, China.

PubMed

Chen, Qiong; Yang, Hailan; Feng, Yongliang; Zhang, Ping; Wu, Weiwei; Li, Shuzhen; Thompson, Brian; Wang, Xin; Peng, Tingting; Wang, Fang; Xie, Bingjie; Guo, Pengge; Li, Mei; Wang, Ying; Zhao, Nan; Wang, Suping; Zhang, Yawei

2018-03-01

Gestational diabetes mellitus is a growing public health concern due to its large disease burden; however, the underlying pathophysiology remains unclear. Therefore, we examined the relationship between 107 single-nucleotide polymorphisms in insulin signalling pathway genes and gestational diabetes mellitus risk using a nested case-control study. The SOS1 rs7598922 GA and AA genotype were statistically significantly associated with reduced gestational diabetes mellitus risk ( p trend  = 0.0006) compared with GG genotype. At the gene level, SOS1 was statistically significantly associated with gestational diabetes mellitus risk after adjusting for multiple comparisons. Moreover, AGGA and GGGG haplotypes in SOS1 gene were associated with reduced risk of gestational diabetes mellitus. Our study provides evidence for an association between the SOS1 gene and risk of gestational diabetes mellitus; however, its role in the pathogenesis of gestational diabetes mellitus will need to be verified by further studies.

Risk of atrial fibrillation among bisphosphonate users: a multicenter, population-based, Italian study.

PubMed

Herrera, L; Leal, I; Lapi, F; Schuemie, M; Arcoraci, V; Cipriani, F; Sessa, E; Vaccheri, A; Piccinni, C; Staniscia, T; Vestri, A; Di Bari, M; Corrao, G; Zambon, A; Gregori, D; Carle, F; Sturkenboom, M; Mazzaglia, G; Trifiro, G

2015-05-01

Bisphosphonate treatment is used to prevent bone fractures. A controversial association of bisphosphonate use and risk of atrial fibrillation has been reported. In our study, current alendronate users were associated with a higher risk of atrial fibrillation as compared with those who had stopped bisphosphonate (BP) therapy for more than 1 year. Bisphosphonates are widely used to prevent bone fractures. Controversial findings regarding the association between bisphosphonate use and the risk of atrial fibrillation (AF) have been reported. The aim of this study was to evaluate the risk of AF in association with BP exposure. We performed a nested case-control study using the databases of drug-dispensing and hospital discharge diagnoses from five Italian regions. The data cover a period ranging from July 1, 2003 to December 31, 2006. The study population comprised new users of bisphosphonates aged 55 years and older. Patients were followed from the first BP prescription until an occurrence of an AF diagnosis (index date, i.e., ID), cancer, death, or the end of the study period, whichever came first. For the risk estimation, any AF case was matched by age and sex to up to 10 controls from the same source population. A conditional logistic regression was performed to obtain the odds ratio with 95% confidence intervals (CI). The BP exposure was classified into current (<90 days prior to ID), recent (91-180), past (181-364), and distant past (≥365) use, with the latter category being used as a reference point. A subgroup analysis by individual BP was then carried out. In comparison with distant past users of BP, current users of BP showed an almost twofold increased risk of AF: odds ratio (OR) = 1.78 and 95% CI = 1.46-2.16. Specifically, alendronate users were mostly associated with AF as compared with distant past use of BP (OR, 1.97; 95% CI, 1.59-2.43). In our nested case-control study, current users of BP are associated with a higher risk of atrial fibrillation as compared with those who had stopped BP treatment for more than 1 year.

Cytochrome P450 2E1 gene polymorphisms/haplotypes and anti-tuberculosis drug-induced hepatitis in a Chinese cohort.

PubMed

Tang, Shaowen; Lv, Xiaozhen; Zhang, Yuan; Wu, Shanshan; Yang, Zhirong; Xia, Yinyin; Tu, Dehua; Deng, Peiyuan; Ma, Yu; Chen, Dafang; Zhan, Siyan

2013-01-01

The pathogenic mechanism of anti-tuberculosis (anti-TB) drug-induced hepatitis is associated with drug metabolizing enzymes. No tagging single-nucleotide polymorphisms (tSNPs) of cytochrome P450 2E1(CYP2E1) in the risk of anti-TB drug-induced hepatitis have been reported. The present study was aimed at exploring the role of tSNPs in CYP2E1 gene in a population-based anti-TB treatment cohort. A nested case-control study was designed. Each hepatitis case was 14 matched with controls by age, gender, treatment history, disease severity and drug dosage. The tSNPs were selected by using Haploview 4.2 based on the HapMap database of Han Chinese in Beijing, and detected by using TaqMan allelic discrimination technology. Eighty-nine anti-TB drug-induced hepatitis cases and 356 controls were included in this study. 6 tSNPs (rs2031920, rs2070672, rs915908, rs8192775, rs2515641, rs2515644) were genotyped and minor allele frequencies of these tSNPs were 21.9%, 23.0%, 19.1%, 23.6%, 20.8% and 44.4% in the cases and 20.9%, 22.7%, 18.9%, 23.2%, 18.2% and 43.2% in the controls, respectively. No significant difference was observed in genotypes or allele frequencies of the 6 tSNPs between case group and control group, and neither of haplotypes in block 1 nor in block 2 was significantly associated with the development of hepatitis. Based on the Chinese anti-TB treatment cohort, we did not find a statistically significant association between genetic polymorphisms of CYP2E1 and the risk of anti-TB drug-induced hepatitis. None of the haplotypes showed a significant association with the development of hepatitis in Chinese TB population.

Vernal keratoconjunctivitis in school children in Rwanda and its association with socio-economic status: a population-based survey.

PubMed

Smedt, Stefan De; Nkurikiye, John; Fonteyne, Yannick; Hogewoning, Arjan; Esbroeck, Marjan Van; Bacquer, Dirk De; Tuft, Stephen; Gilbert, Clare; Delanghe, Joris; Kestelyn, Philippe

2011-10-01

Vernal keratoconjunctivitis (VKC) is an allergic eye disease and an important cause of hospital referral among children in Africa and Asia. Hospital-based studies have suggested a role for parasites in its pathogenesis. To determine the prevalence and risk factors for VKC in Central Africa, we conducted a nested population-based case control study in Rwanda, involving randomly selected primary schools from different environments (rural/urban) and climate. A prevalence of VKC of 4.0% (95% confidence interval 3.3-4.7%) was found among 3,041 children studied (participation rate 94.7%). The intestinal parasitic burden was not related to VKC. Besides hot dry climate (odds ratio [OR] = 1.5, P = 0.05) and male gender (OR = 1.7, P = 0.005), multivariate analysis identified higher economic status as a risk for VKC (OR = 1.4, P = 0.005). The effect on VKC of higher economic status appears not to act through differences in parasitic intestinal load.

Vernal Keratoconjunctivitis in School Children in Rwanda and Its Association with Socio-Economic Status: A Population-Based Survey

PubMed Central

Smedt, Stefan De; Nkurikiye, John; Fonteyne, Yannick; Hogewoning, Arjan; Esbroeck, Marjan Van; Bacquer, Dirk De; Tuft, Stephen; Gilbert, Clare; Delanghe, Joris; Kestelyn, Philippe

2011-01-01

Vernal keratoconjunctivitis (VKC) is an allergic eye disease and an important cause of hospital referral among children in Africa and Asia. Hospital-based studies have suggested a role for parasites in its pathogenesis. To determine the prevalence and risk factors for VKC in Central Africa, we conducted a nested population-based case control study in Rwanda, involving randomly selected primary schools from different environments (rural/urban) and climate. A prevalence of VKC of 4.0% (95% confidence interval 3.3–4.7%) was found among 3,041 children studied (participation rate 94.7%). The intestinal parasitic burden was not related to VKC. Besides hot dry climate (odds ratio [OR] = 1.5, P = 0.05) and male gender (OR = 1.7, P = 0.005), multivariate analysis identified higher economic status as a risk for VKC (OR = 1.4, P = 0.005). The effect on VKC of higher economic status appears not to act through differences in parasitic intestinal load. PMID:21976577

Chromium Exposure and Risk of Cardiovascular Disease in High Cardiovascular Risk Subjects　- Nested Case-Control Study in the Prevention With Mediterranean Diet (PREDIMED) Study.

PubMed

Gutiérrez-Bedmar, Mario; Martínez-González, Miguel Ángel; Muñoz-Bravo, Carlos; Ruiz-Canela, Miguel; Mariscal, Alberto; Salas-Salvadó, Jordi; Estruch, Ramón; Corella, Dolores; Arós, Fernando; Fito, Monserrat; Lapetra, José; Serra-Majem, Lluís; Pintó, Xavier; Alonso-Gómez, Ángel; Portoles, Olga; Fiol, Miquel; Bulló, Mónica; Castañer, Olga; Ros, Emilio; Gómez-Gracia, Enrique

2017-07-25

Epidemiological data on chromium (Cr) exposure and the risk of cardiovascular disease (CVD) are still limited. Toenail Cr level (TCL) provides a time-integrated measure reflecting long-term Cr exposure. We measured TCL to assess the hypothesis that long-term Cr exposure was inversely associated with incident CVD in a population at high risk for CVD.Methods and Results:The associations between TCL and CVD were evaluated in a case-control study nested within the "PREvención con DIeta MEDiterránea" (PREDIMED) trial. We randomly selected 147 of the 288 patients diagnosed with CVD during follow-up and matched them on age and sex to 271 controls. Instrumental neutron activation analysis was used to assess TCL. In-person interviews, medical record reviews, and validated questionnaires were used to assess covariates. The fully adjusted OR for the highest vs. lowest quartile of toenail Cr was 0.54 (95% CI: 0.26-1.14; P trend =0.189) for the nested case-control study. On stratification for diabetes mellitus (DM), OR was 1.37 (95% CI: 0.54-3.46; P trend =0.364) for the DM group, and 0.25 (95% CI: 0.08-0.80; P trend =0.030) for the non-DM group (P for interaction=0.078). The present findings, although not statistically significant, are consistent with previously reported inverse associations between TCL and CVD. These results, especially for non-DM patients, increase the limited epidemiological knowledge about the possible protective role of Cr against CVD. (Trial registration: www.controlled-trials.com; ISRCTN35739639.).

The Leganés cognitive test correlates poorly with MRI evidence of global cortical atrophy in an underserved community: A population-based and nested case-control study in rural Ecuador (The Atahualpa Project)

PubMed Central

Brutto, Oscar H. Del; Mera, Robertino M; Zambrano, Mauricio; Lama, Julio

2014-01-01

Objective We aimed to evaluate whether the Leganés cognitive test (LCT) correlates with global cortical atrophy (GCA) and can be used as a surrogate for structural brain damage. Methods Atahualpa residents aged > 60 years identified during a door-to-door survey underwent MRI for grading GCA. Using multivariate generalized linear models, we evaluated whether continuous LCT scores correlated with GCA, after adjusting for demographics, education, cardiovascular health (CVH) status, depression and edentulism. In a nested case-control study, GCA severity was assessed in subjects with LCT scores below the cutoff level for dementia (< 22 points) and in matched controls without dementia. Results Out of 311 eligible subjects, 241 (78%) were enrolled. Mean age was 69.2±7.5 years, 59% were women, 83% had primary school education, 73% had poor CVH status, 12% had symptoms of depression and 43% had edentulism. Average LCT score was 26.7±3, and 23 (9.5%) subjects scored < 22 points. GCA was mild in 108, moderate in 95, and severe in 26 individuals. On the multivariate model, mean LCT score was not associated with GCA severity (β=0.06, SE=0.34, p=0.853). Severe GCA was noted in 6 / 23 case-patients and in 8 / 23 controls (OR: 0.67, 95% CI: 0.14-2.81, p=0.752, McNemar's test). Conclusion The LCT does not correlate with severity of GCA after adjusting for potential confounding variables, and should not be used as a reliable estimate of structural brain damage. PMID:29213925

The Leganés cognitive test correlates poorly with MRI evidence of global cortical atrophy in an underserved community: A population-based and nested case-control study in rural Ecuador (The Atahualpa Project).

PubMed

Brutto, Oscar H Del; Mera, Robertino M; Zambrano, Mauricio; Lama, Julio

2014-01-01

We aimed to evaluate whether the Leganés cognitive test (LCT) correlates with global cortical atrophy (GCA) and can be used as a surrogate for structural brain damage. Atahualpa residents aged > 60 years identified during a door-to-door survey underwent MRI for grading GCA. Using multivariate generalized linear models, we evaluated whether continuous LCT scores correlated with GCA, after adjusting for demographics, education, cardiovascular health (CVH) status, depression and edentulism. In a nested case-control study, GCA severity was assessed in subjects with LCT scores below the cutoff level for dementia (< 22 points) and in matched controls without dementia. Out of 311 eligible subjects, 241 (78%) were enrolled. Mean age was 69.2±7.5 years, 59% were women, 83% had primary school education, 73% had poor CVH status, 12% had symptoms of depression and 43% had edentulism. Average LCT score was 26.7±3, and 23 (9.5%) subjects scored < 22 points. GCA was mild in 108, moderate in 95, and severe in 26 individuals. On the multivariate model, mean LCT score was not associated with GCA severity (β=0.06, SE=0.34, p=0.853). Severe GCA was noted in 6 / 23 case-patients and in 8 / 23 controls (OR: 0.67, 95% CI: 0.14-2.81, p=0.752, McNemar's test). The LCT does not correlate with severity of GCA after adjusting for potential confounding variables, and should not be used as a reliable estimate of structural brain damage.

Low-grade parasitaemias and cold agglutinins in patients with hyper-reactive malarious splenomegaly and acute haemolysis.

PubMed

Torres, J R; Villegas, L; Perez, H; Suarez, L; Torres V, M A; Campos, M

2003-03-01

A cluster of 16 cases of hyper-reactive malarious splenomegaly (HMS) with severe, acute haemolysis, from an isolated, Venezuelan, Yanomami population, was prospectively investigated. Nine (69%) of the 13 HMS sera investigated but only one (7%) of 14 control sera (P < 0.005) contained elevated titres (of at least 1:32) of complement-fixing IgM cold agglutinins (CA). The CA detected had specificity for both the I and i blood-group antigens (with a relative predominance of anti-I) and wide thermal stability. The mean reciprocal CA titre was much higher for the HMS sera than for the control samples (59.16 v. 2.28; P < 0.001). Indirect tests for antiglobulin were positive for two of the 13 HMS cases (but none of 14 controls) investigated; all of the direct tests for antiglobulin gave negative results. The seven HMS cases checked, using an assay based on a nested PCR which amplified species-specific ribosomal sequences from Plasmodium vivax or P. falciparum, each yielded the PCR product that indicated P. vivax infection. However, only six (25%) of the 24 control samples (collected, at the same time as the HMS samples, from asymptomatic adults from the same Yanomami population) were PCR-positive (P < 0.001). In some cases at least, the acute severe episodes of haemolysis occasionally seen in HMS appear to be associated with an auto-immune, cold-agglutinin-mediated response triggered by non-patent parasitaemias.

Risk factors for asthma and allergy associated with urban migration: background and methodology of a cross-sectional study in Afro-Ecuadorian school children in Northeastern Ecuador (Esmeraldas-SCAALA Study).

PubMed

Cooper, Philip J; Chico, Martha E; Vaca, Maritza G; Rodriguez, Alejandro; Alcântara-Neves, Neuza M; Genser, Bernd; de Carvalho, Lain Pontes; Stein, Renato T; Cruz, Alvaro A; Rodrigues, Laura C; Barreto, Mauricio L

2006-09-13

Asthma and allergic diseases are becoming increasingly frequent in children in urban centres of Latin America although the prevalence of allergic disease is still low in rural areas. Understanding better why the prevalence of asthma is greater in urban migrant populations and the role of risk factors such as life style and environmental exposures, may be key to understand what is behind this trend. The Esmeraldas-SCAALA (Social Changes, Asthma and Allergy in Latin America) study consists of cross-sectional and nested case-control studies of school children in rural and urban areas of Esmeraldas Province in Ecuador. The cross-sectional study will investigate risk factors for atopy and allergic disease in rural and migrant urban Afro-Ecuadorian school children and the nested case-control study will examine environmental, biologic and social risk factors for asthma among asthma cases and non-asthmatic controls from the cross-sectional study. Data will be collected through standardised questionnaires, skin prick testing to relevant aeroallergen extracts, stool examinations for parasites, blood sampling (for measurement of IgE, interleukins and other immunological parameters), anthropometric measurements for assessment of nutritional status, exercise testing for assessment of exercise-induced bronchospasm and dust sampling for measurement of household endotoxin and allergen levels. The information will be used to identify the factors associated with an increased risk of asthma and allergies in migrant and urbanizing populations, to improve the understanding of the causes of the increase in asthma prevalence and to identify potentially modifiable factors to inform the design of prevention programmes to reduce the risk of allergy in urban populations in Latin America.

Risk factors for asthma and allergy associated with urban migration: background and methodology of a cross-sectional study in Afro-Ecuadorian school children in Northeastern Ecuador (Esmeraldas-SCAALA Study)

PubMed Central

Cooper, Philip J; Chico, Martha E; Vaca, Maritza G; Rodriguez, Alejandro; Alcântara-Neves, Neuza M; Genser, Bernd; de Carvalho, Lain Pontes; Stein, Renato T; Cruz, Alvaro A; Rodrigues, Laura C; Barreto, Mauricio L

2006-01-01

Background Asthma and allergic diseases are becoming increasingly frequent in children in urban centres of Latin America although the prevalence of allergic disease is still low in rural areas. Understanding better why the prevalence of asthma is greater in urban migrant populations and the role of risk factors such as life style and environmental exposures, may be key to understand what is behind this trend. Methods/design The Esmeraldas-SCAALA (Social Changes, Asthma and Allergy in Latin America) study consists of cross-sectional and nested case-control studies of school children in rural and urban areas of Esmeraldas Province in Ecuador. The cross-sectional study will investigate risk factors for atopy and allergic disease in rural and migrant urban Afro-Ecuadorian school children and the nested case-control study will examine environmental, biologic and social risk factors for asthma among asthma cases and non-asthmatic controls from the cross-sectional study. Data will be collected through standardised questionnaires, skin prick testing to relevant aeroallergen extracts, stool examinations for parasites, blood sampling (for measurement of IgE, interleukins and other immunological parameters), anthropometric measurements for assessment of nutritional status, exercise testing for assessment of exercise-induced bronchospasm and dust sampling for measurement of household endotoxin and allergen levels. Discussion The information will be used to identify the factors associated with an increased risk of asthma and allergies in migrant and urbanizing populations, to improve the understanding of the causes of the increase in asthma prevalence and to identify potentially modifiable factors to inform the design of prevention programmes to reduce the risk of allergy in urban populations in Latin America. PMID:16970809

Analysis of Clinical Cohort Data Using Nested Case-control and Case-cohort Sampling Designs. A Powerful and Economical Tool.

PubMed

Ohneberg, K; Wolkewitz, M; Beyersmann, J; Palomar-Martinez, M; Olaechea-Astigarraga, P; Alvarez-Lerma, F; Schumacher, M

2015-01-01

Sampling from a large cohort in order to derive a subsample that would be sufficient for statistical analysis is a frequently used method for handling large data sets in epidemiological studies with limited resources for exposure measurement. For clinical studies however, when interest is in the influence of a potential risk factor, cohort studies are often the first choice with all individuals entering the analysis. Our aim is to close the gap between epidemiological and clinical studies with respect to design and power considerations. Schoenfeld's formula for the number of events required for a Cox' proportional hazards model is fundamental. Our objective is to compare the power of analyzing the full cohort and the power of a nested case-control and a case-cohort design. We compare formulas for power for sampling designs and cohort studies. In our data example we simultaneously apply a nested case-control design with a varying number of controls matched to each case, a case cohort design with varying subcohort size, a random subsample and a full cohort analysis. For each design we calculate the standard error for estimated regression coefficients and the mean number of distinct persons, for whom covariate information is required. The formula for the power of a nested case-control design and the power of a case-cohort design is directly connected to the power of a cohort study using the well known Schoenfeld formula. The loss in precision of parameter estimates is relatively small compared to the saving in resources. Nested case-control and case-cohort studies, but not random subsamples yield an attractive alternative for analyzing clinical studies in the situation of a low event rate. Power calculations can be conducted straightforwardly to quantify the loss of power compared to the savings in the num-ber of patients using a sampling design instead of analyzing the full cohort.

Migratory patterns and population structure among breeding and wintering red-breasted mergansers (Mergus serrator) and common mergansers (M. merganser)

USGS Publications Warehouse

Pearce, J.M.; McCracken, K.G.; Christensen, Thomas K.; Zhuravlev, Y.N.

2009-01-01

Philopatry has long been assumed to structure populations of waterfowl and other species of birds genetically, especially via maternally transmitted mitochondrial DNA (mtDNA), yet other migratory behaviors and nesting ecology (use of ground vs. cavity sites) may also contribute to population genetic structure. We investigated the effects of migration and nesting ecology on the population genetic structure of two Holarctic waterfowl, the Red-breasted Merganser (Mergus serrator) and Common Merganser (M. merganser), using mtDNA control-region sequence data. Red-breasted Mergansers (a ground-nesting species) exhibited lower levels of population differentiation across their North American range, possibly as a result of post-Pleistocene range expansion and population growth. By contrast, Common Mergansers (a cavity-nesting species) breeding in western and eastern North America were strongly differentiated, as were continental groups in North America and Europe. Our hypothesis that population differentiation of breeding female Common Mergansers results from limited migration during non-breeding periods was not supported, in that equally heterogeneous mtDNA lineages were observed in males and females on several wintering areas. The interspecific differences in mtDNA patterns for these two closely related species may have resulted from factors related to nesting ecology (ground vs. cavity nesting) and responses to historical climate change.

Dynamics of habitat selection in birds: adaptive response to nest predation depends on multiple factors.

PubMed

Devries, J H; Clark, R G; Armstrong, L M

2018-05-01

According to theory, habitat selection by organisms should reflect underlying habitat-specific fitness consequences and, in birds, reproductive success has a strong impact on population growth in many species. Understanding processes affecting habitat selection also is critically important for guiding conservation initiatives. Northern pintails (Anas acuta) are migratory, temperate-nesting birds that breed in greatest concentrations in the prairies of North America and their population remains below conservation goals. Habitat loss and changing land use practices may have decoupled formerly reliable fitness cues with respect to nest habitat choices. We used data from 62 waterfowl nesting study sites across prairie Canada (1997-2009) to examine nest survival, a primary fitness metric, at multiple scales, in combination with estimates of habitat selection (i.e., nests versus random points), to test for evidence of adaptive habitat choices. We used the same habitat covariates in both analyses. Pintail nest survival varied with nest initiation date, nest habitat, pintail breeding pair density, landscape composition and annual moisture. Selection of nesting habitat reflected patterns in nest survival in some cases, indicating adaptive selection, but strength of habitat selection varied seasonally and depended on population density and landscape composition. Adaptive selection was most evident late in the breeding season, at low breeding densities and in cropland-dominated landscapes. Strikingly, at high breeding density, habitat choice appears to become maladaptive relative to nest predation. At larger spatial scales, the relative availability of habitats with low versus high nest survival, and changing land use practices, may limit the reproductive potential of pintails.

Effects of southern flying squirrels Glaucomys volans on red-cockaded woodpecker Picoides borealis reproductive success

USGS Publications Warehouse

Laves, K.S.; Loeb, S.C.

1999-01-01

Anecdotal data gathered from many populations suggest that southern flying squirrel (SFS, Glaucomys volans) use of the endangered red-cockaded woodpecker's (RCW, Picoides borealis) nest and roost cavities may negatively affect RCW populations. We conducted a controlled experiment to determine the effects of SFSs on RCW reproductive success. During the 1994 and 1995 breeding seasons, SFSs were removed from 30 RCW clusters and 32 clusters served as controls. SFSs were the most frequently encountered occupants of RCW cavities and used 20-33% of RCW cavities in control and treatment clusters over both years. Treatment groups produced significantly more successful nests (??? 1 fledgling) than control groups in 1994. In 1995 however, there was no difference in the number of successful nests. In both years, RCW groups nesting in treatment clusters produced significantly more fledglings than groups in control clusters in each of four experimental areas, averaging approximately 0.7 additional fledglings per nesting group. Loss of entire clutches or broods, possibly as a result of predation or abandonment, was a major factor limiting reproduction in control groups in 1994. In contrast, differences in partial brood loss appeared to be the cause of differential fledging success in 1995 Usurpation of RCW roost cavities by SFSs may have placed greater energetic demands on RCWs for cavity defence or thermoregulation, thus reducing energy available for reproduction. Our results show that SFS use of RCW cavities during the breeding season has a significant impact on RCWs and that management of RCW populations should include activities that either minimize SFS populations in RCW clusters or limit access of SFSs to RCW cavities.

Modeling and E-M estimation of haplotype-specific relative risks from genotype data for a case-control study of unrelated individuals.

PubMed

Stram, Daniel O; Leigh Pearce, Celeste; Bretsky, Phillip; Freedman, Matthew; Hirschhorn, Joel N; Altshuler, David; Kolonel, Laurence N; Henderson, Brian E; Thomas, Duncan C

2003-01-01

The US National Cancer Institute has recently sponsored the formation of a Cohort Consortium (http://2002.cancer.gov/scpgenes.htm) to facilitate the pooling of data on very large numbers of people, concerning the effects of genes and environment on cancer incidence. One likely goal of these efforts will be generate a large population-based case-control series for which a number of candidate genes will be investigated using SNP haplotype as well as genotype analysis. The goal of this paper is to outline the issues involved in choosing a method of estimating haplotype-specific risk estimates for such data that is technically appropriate and yet attractive to epidemiologists who are already comfortable with odds ratios and logistic regression. Our interest is to develop and evaluate extensions of methods, based on haplotype imputation, that have been recently described (Schaid et al., Am J Hum Genet, 2002, and Zaykin et al., Hum Hered, 2002) as providing score tests of the null hypothesis of no effect of SNP haplotypes upon risk, which may be used for more complex tasks, such as providing confidence intervals, and tests of equivalence of haplotype-specific risks in two or more separate populations. In order to do so we (1) develop a cohort approach towards odds ratio analysis by expanding the E-M algorithm to provide maximum likelihood estimates of haplotype-specific odds ratios as well as genotype frequencies; (2) show how to correct the cohort approach, to give essentially unbiased estimates for population-based or nested case-control studies by incorporating the probability of selection as a case or control into the likelihood, based on a simplified model of case and control selection, and (3) finally, in an example data set (CYP17 and breast cancer, from the Multiethnic Cohort Study) we compare likelihood-based confidence interval estimates from the two methods with each other, and with the use of the single-imputation approach of Zaykin et al. applied under both null and alternative hypotheses. We conclude that so long as haplotypes are well predicted by SNP genotypes (we use the Rh2 criteria of Stram et al. [1]) the differences between the three methods are very small and in particular that the single imputation method may be expected to work extremely well. Copyright 2003 S. Karger AG, Basel

Use of Hypoprothrombinemia-Inducing Cephalosporins and the Risk of Hemorrhagic Events: A Nationwide Nested Case-Control Study

PubMed Central

Shen, Li-Jiuan; Wu, Fe-Lin Lin; Tsay, Woei; Hung, Chien-Ching; Lin, Shu-Wen

2016-01-01

Objective Existing data regarding the risk of hemorrhagic events associated with exposure to hypoprothrombinemia-inducing cephalosporins are limited by the small sample size. This population-based study aimed to examine the association between exposure to hypoprothrombinemia-inducing cephalosporins and hemorrhagic events using National Health Insurance Research Database in Taiwan. Design A nationwide nested case-control study. Setting National Health Insurance Research database. Participants We conducted a nested case-control study within a cohort of 6191 patients who received hypoprothrombinemia-inducing cephalosporins and other antibiotics for more than 48 hours. Multivariable conditional logistic regressions were used to calculate the adjusted odds ratio (aOR) and 95% confidence interval (CI) for hemorrhagic events associated with exposure to hypoprothrombinemia-inducing cephalosporins (overall, cumulative dose measured as defined daily dose (DDD), and individual cephalosporins). Results Within the cohort, we identified 704 patients with hemorrhagic events and 2816 matched controls. Use of hypoprothrombinemia-inducing cephalosporins was associated with increased risk of hemorrhagic events (aOR, 1.71; 95% CI, 1.42–2.06), which increased with higher cumulative doses (<3 DDDs, aOR 1.62; 3–5 DDDs, aOR 1.78; and >5 DDDs, aOR 1.89). The aOR for individual cephalosporin was 2.88 (95% CI, 2.08–4.00), 1.35 (1.09–1.67) and 4.57 (2.63–7.95) for cefmetazole, flomoxef, and cefoperazone, respectively. Other risk factors included use of anticoagulants (aOR 2.08 [95% CI, 1.64–2.63]), liver failure (aOR 1.69 [1.30–2.18]), poor nutritional status (aOR 1.41 [1.15–1.73]), and history of hemorrhagic events (aOR 2.57 [1.94–3.41]) 6 months prior to the index date. Conclusions Use of hypoprothrombinemia-inducing cephalosporins increases risk of hemorrhagic events. Close watch for hemorrhagic events is recommended when prescribing these cephalosporins, especially in patients who are at higher risk. PMID:27463687

Asthma, chronic bronchitis, and exposure to irritant agents in occupational domestic cleaning: a nested case-control study.

PubMed

Medina-Ramón, M; Zock, J P; Kogevinas, M; Sunyer, J; Torralba, Y; Borrell, A; Burgos, F; Antó, J M

2005-09-01

Women employed in domestic cleaning are at increased risk for symptoms of obstructive lung disease, but the agents responsible are unknown. To investigate common tasks and products in occupational domestic cleaning in relation to respiratory morbidity. Case-control study in domestic cleaning women nested within a large population based survey of women aged 30-65 years; 160 domestic cleaning women with asthma symptoms, chronic bronchitis symptoms, or both and 386 without a history of respiratory symptoms were identified. Detailed exposures were evaluated for 40 cases who reported still having symptoms at the recruitment interview, and 155 controls who reported not having symptoms. All tasks performed and products used when cleaning houses were determined in a face-to-face interview. Lung function, methacholine challenge, and serum IgE testing were performed. Personal exposure measurements of airborne chlorine and ammonia were performed in a subsample. Associations between asthma, chronic bronchitis, and cleaning exposures were evaluated using multiple logistic regression analysis. Airborne chlorine (median level 0-0.4 ppm) and ammonia (0.6-6.4 ppm) were detectable during occupational domestic cleaning activities. Cases used bleach more frequently than controls; adjusted odds ratio (OR) for intermediate exposure was 3.3 (95% CI 0.9 to 11) and for high exposure 4.9 (1.5 to 15). Other independent associations included accidental inhalation of vapours and gases from cleaning agents and washing dishes. These associations were more pronounced for cases with asthma symptoms than for those with symptoms of chronic bronchitis, but were not related to sensitisation to common allergens. Asthma symptoms in domestic cleaning women are associated with exposure to bleach and possibly other irritant agents. The public health impact of the use of irritant cleaning products could be widespread since the use of these products is common both in the workplace and at home.

Use of proton pump inhibitors is associated with fractures in young adults: a population-based study.

PubMed

Freedberg, D E; Haynes, K; Denburg, M R; Zemel, B S; Leonard, M B; Abrams, J A; Yang, Y-X

2015-10-01

Proton pump inhibitors (PPIs) are associated with risk for fracture in osteoporotic adults. In this population-based study, we found a significant association between PPIs and fracture in young adults, with evidence of a dose-response effect. Young adults who use PPIs should be cautioned regarding risk for fracture. Proton pump inhibitors (PPIs) are associated with fracture in adults with osteoporosis. Because PPI therapy may interfere with bone accrual and attainment of peak bone mineral density, we studied the association between use of PPIs and fracture in children and young adults. We conducted a population-based, case-control study nested within records from general medical practices from 1994 to 2013. Participants were 4-29 years old with ≥ 1 year of follow-up who lacked chronic conditions associated with use of long-term acid suppression. Cases of fracture were defined as the first incident fracture at any site. Using incidence density sampling, cases were matched with up to five controls by age, sex, medical practice, and start of follow-up. PPI exposure was defined as 180 or more cumulative doses of PPIs. Conditional logistic regression was used to estimate the odds ratio and confidence interval for use of PPIs and fracture. We identified 124,799 cases and 605,643 controls. The adjusted odds ratio for the risk of fracture associated with PPI exposure was 1.13 (95% CI 0.92 to 1.39) among children aged < 18 years old and 1.39 (95% CI 1.26 to 1.53) among young adults aged 18-29 years old. In young adults but not children, we observed a dose-response effect with increased total exposure to PPIs (p for trend <0.001). PPI use was associated with fracture in young adults, but overall evidence did not support a PPI-fracture relationship in children. Young adults who use PPIs should be cautioned regarding potentially increased risk for fracture, even if they lack traditional fracture risk factors.

Wired: impacts of increasing power line use by a growing bird population

NASA Astrophysics Data System (ADS)

Moreira, Francisco; Encarnação, Vitor; Rosa, Gonçalo; Gilbert, Nathalie; Infante, Samuel; Costa, Julieta; D'Amico, Marcello; Martins, Ricardo C.; Catry, Inês

2017-02-01

Power lines are increasingly widespread across many regions of the planet. Although these linear infrastructures are known for their negative impacts on bird populations, through collision and electrocution, some species take advantage of electricity pylons for nesting. In this case, estimation of the net impact of these infrastructures at the population level requires an assessment of trade-offs between positive and negative impacts. We compiled historical information (1958-2014) of the Portuguese white stork Ciconia ciconia population to analyze long-term changes in numbers, distribution range and use of nesting structures. White stork population size increased 660% up to 12000 breeding pairs between 1984 and 2014. In the same period, the proportion of nests on electricity pylons increased from 1% to 25%, likely facilitated by the 60% increase in the length of the very high tension power line grid (holding the majority of the nests) in the stork’s distribution range. No differences in breeding success were registered for storks nesting on electricity pylons versus other structures, but a high risk of mortality by collision and electrocution with power lines was estimated. We discuss the implications of this behavioral change, and of the management responses by power line companies, both for stork populations and for managers.

Prenatal Phthalates, Maternal Thyroid Function, and Risk of Attention-Deficit Hyperactivity Disorder in the Norwegian Mother and Child Cohort.

PubMed

Engel, Stephanie M; Villanger, Gro D; Nethery, Rachel C; Thomsen, Cathrine; Sakhi, Amrit K; Drover, Samantha S M; Hoppin, Jane A; Zeiner, Pal; Knudsen, Gun Peggy; Reichborn-Kjennerud, Ted; Herring, Amy H; Aase, Heidi

2018-05-10

There is growing concern that phthalate exposures may have an impact on child neurodevelopment. Prenatal exposure to phthalates has been linked with externalizing behaviors and executive functioning defects suggestive of an attention-deficit hyperactivity disorder (ADHD) phenotype. We undertook an investigation into whether prenatal exposure to phthalates was associated with clinically confirmed ADHD in a population-based nested case-control study of the Norwegian Mother and Child Cohort (MoBa) between the years 2003 and 2008. Phthalate metabolites were measured in maternal urine collected at midpregnancy. Cases of ADHD ( n =297) were obtained through linkage between MoBa and the Norwegian National Patient Registry. A random sample of controls ( n =553) from the MoBa population was obtained. In multivariable adjusted coexposure models, the sum of di-2-ethylhexyl phthalate metabolites (∑DEHP) was associated with a monotonically increasing risk of ADHD. Children of mothers in the highest quintile of had almost three times the odds of an ADHD diagnosis as those in the lowest [OR=2.99 (95% CI: 1.47, 5.49)]. When ∑DEHP was modeled as a log-linear (natural log) term, for each log-unit increase in exposure, the odds of ADHD increased by 47% [OR=1.47 (95% CI: 1.09, 1.94)]. We detected no significant modification by sex or mediation by prenatal maternal thyroid function or by preterm delivery. In this population-based case-control study of clinical ADHD, maternal urinary concentrations of DEHP were monotonically associated with increased risk of ADHD. Additional research is needed to evaluate potential mechanisms linking phthalates to ADHD. https://doi.org/10.1289/EHP2358.

Predation and infanticide influence ideal free choice by a parrot occupying heterogeneous tropical habitats.

PubMed

Bonebrake, Timothy C; Beissinger, Steven R

2010-06-01

The ideal free distribution (IFD) predicts that organisms will disperse to sites that maximize their fitness based on availability of resources. Habitat heterogeneity underlies resource variation and influences spatial variation in demography and the distribution of populations. We relate nest site productivity at multiple scales measured over a decade to habitat quality in a box-nesting population of Forpus passerinus (green-rumped parrotlets) in Venezuela to examine critical IFD assumptions. Variation in reproductive success at the local population and neighborhood scales had a much larger influence on productivity (fledglings per nest box per year) than nest site or female identity. Habitat features were reliable cues of nest site quality. Nest sites with less vegetative cover produced greater numbers of fledglings than sites with more cover. However, there was also a competitive cost to nesting in high-quality, low-vegetative cover nest boxes, as these sites experienced the most infanticide events. In the lowland local population, water depth and cover surrounding nest sites were related with F. passerinus productivity. Low vegetative cover and deeper water were associated with lower predation rates, suggesting that predation could be a primary factor driving habitat selection patterns. Parrotlets also demonstrated directional dispersal. Pairs that changed nest sites were more likely to disperse from poor-quality nest sites to high-quality nest sites rather than vice versa, and juveniles were more likely to disperse to, or remain in, the more productive of the two local populations. Parrotlets exhibited three characteristics fundamental to the IFD: habitat heterogeneity within and between local populations, reliable habitat cues to productivity, and active dispersal to sites of higher fitness.

Risk of cancer among HIV-infected patients from a population-based nested case-control study: implications for cancer prevention.

PubMed

Chen, Chang-Hua; Chung, Chih-Yuan; Wang, Li-Hsuan; Lin, Che; Lin, Hsiu-Li; Lin, Hsiu-Chen

2015-03-16

The burden of cancer is likely to increase among the human immunodeficiency virus (HIV)-positive population as it ages due to successful antiretroviral therapy (ART). The purpose of this study was to determine the risk of cancer in HIV-infected patients. This study was a matched nested case-control study. It was performed using the National Health Insurance Research Database of Taiwan. The control group included non-HIV-infected patients matched by sex, age, and year of enrollment. Logistic regression analyses were performed and simultaneously adjusted for potential confounders (income, urbanization, and Charslon index of comorbidity to evaluate HIV infection as an independent risk of cancer. We calculated the overall and sex-specific standardized incidence ratios (SIR) to investigate the pattern of cancer risk and overall cancer risk in the patients with HIV infection. Of the 1,115 HIV-infected patients, 104 (9.33%) developed cancer during the 11-year follow-up period. The risk of cancer for patients with HIV infection was significant (adjusted odds ratio = 3.89, 95% confidence interval [CI] = 2.92-5.19) after adjustment for potential confounders. There was a significantly increased risk of developing non-Hodgkin lymphoma (SIR = 25.73, 95% CI = 6.83-90.85), cervical cancer (SIR = 4.01, 95% CI = 1.0-16.06), lymphoma (SIR = 20.26, 95% CI = 5.86-70.10), and respiratory and intrathoracic cancer (SIR = 20.09, 95% CI = 2.34-172.09) compared with the control group. In addition, HIV-infected patients were at significant risk for renal, oral, breast, liver, skin, and colorectal cancer. Patients with HIV infection are at increased risk for several specific cancers. Our results support the implementation of an active and accelerated cancer screening schedule for patients with HIV infection to increase their life span.

Comparative population structure of cavity-nesting sea ducks

USGS Publications Warehouse

Pearce, John M.; Eadie, John M.; Savard, Jean-Pierre L.; Christensen, Thomas K.; Berdeen, James; Taylor, Eric J.; Boyd, Sean; Einarsson, Árni

2014-01-01

A growing collection of mtDNA genetic information from waterfowl species across North America suggests that larger-bodied cavity-nesting species exhibit greater levels of population differentiation than smaller-bodied congeners. Although little is known about nest-cavity availability for these species, one hypothesis to explain differences in population structure is reduced dispersal tendency of larger-bodied cavity-nesting species due to limited abundance of large cavities. To investigate this hypothesis, we examined population structure of three cavity-nesting waterfowl species distributed across much of North America: Barrow's Goldeneye (Bucephala islandica), Common Goldeneye (B. clangula), and Bufflehead (B. albeola). We compared patterns of population structure using both variation in mtDNA control-region sequences and band-recovery data for the same species and geographic regions. Results were highly congruent between data types, showing structured population patterns for Barrow's and Common Goldeneye but not for Bufflehead. Consistent with our prediction, the smallest cavity-nesting species, the Bufflehead, exhibited the lowest level of population differentiation due to increased dispersal and gene flow. Results provide evidence for discrete Old and New World populations of Common Goldeneye and for differentiation of regional groups of both goldeneye species in Alaska, the Pacific Northwest, and the eastern coast of North America. Results presented here will aid management objectives that require an understanding of population delineation and migratory connectivity between breeding and wintering areas. Comparative studies such as this one highlight factors that may drive patterns of genetic diversity and population trends.

Testing models of female reproductive migratory behaviour and population structure in the Caribbean hawksbill turtle, Eretmochelys imbricata, with mtDNA sequences.

PubMed

Bass, A L; Good, D A; Bjorndal, K A; Richardson, J I; Hillis, Z M; Horrocks, J A; Bowen, B W

1996-06-01

Information on the reproductive behaviour and population structure of female hawksbill turtles, Eretmochelys imbricata, is necessary to define conservation priorities for this highly endangered species. Two hypotheses to explain female nest site choice, natal homing and social facilitation, were tested by analyzing mtDNA control region sequences of 103 individuals from seven nesting colonies in the Caribbean and western Atlantic. Under the social facilitation model, newly mature females follow older females to a nesting location, and subsequently use this site for future nesting. This model generates an expectation that female lineages will be homogenized among regional nesting colonies. Contrary to expectations of the social facilitation model, mtDNA lineages were highly structured among western Atlantic nesting colonies. These analyses identified at least 6 female breeding stocks in the Caribbean and western Atlantic and support a natal homing model for recruitment of breeding females. Reproductive populations are effectively isolated over ecological time scales, and recovery plans for this species should include protection at the level of individual nesting colonies.

A nested case-control study of predictors for tuberculosis recurrence in a large UK Centre.

PubMed

Rosser, Andrew; Richardson, Matthew; Wiselka, Martin J; Free, Robert C; Woltmann, Gerrit; Mukamolova, Galina V; Pareek, Manish

2018-02-27

Tuberculosis (TB) recurrence represents a challenge to control programs. In low incidence countries, the prevailing risk factors leading to recurrence are poorly characterised. We conducted a nested case-control study using the Leicester TB service TBIT database. Cases were identified from database notifications between 1994 and 2014. Controls had one episode and were matched to cases on a ratio of two to one by the date of notification. Multiple imputation was used to account for missing data. Multivariate conditional logistic regression analysis was employed to identify clinical, sociodemographic and TB specific risk factors for recurrence. From a cohort of 4628 patients, 82 TB recurrences occurred (1.8%). Nineteen of 82 patients had paired isolates with MIRU-VNTR strain type profiles available, of which 84% were relapses and 16% reinfections. On multivariate analysis, smoking (OR 3.8; p = 0.04), grade 3/4 adverse drug reactions (OR 5.6; p = 0.02), ethnicity 'Indian subcontinent' (OR 8.5; p = <0.01), ethnicity 'other' (OR 31.2; p = 0.01) and receipt of immunosuppressants (OR 6.8; p = <0.01) were independent predictors of TB recurrence. Within this UK setting, the rate of TB recurrence was low, predominantly due to relapse. The identification of an elevated recurrence risk amongst the ethnic group contributing most cases to the national TB burden presents an opportunity to improve individual and population health.

The influence of coyotes on an urban Canada goose population in the Chicago metropolitan area

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brown, Justin L.; /Ohio State U.

Canada geese (Branta canadensis) have become common in many urban areas, often creating nuisance problems for human residents. The presence of urban geese has raised concerns about the spread of disease, increased erosion, excessive noise, eutrophication of waterways, and general nuisance problems. Goose populations have grown due to an increase in urbanization resulting in an abundance of high quality food (urban grass) and suitable nesting sites, as well as a decrease in some predators. I monitored nest predation in the Chicago suburbs during the 2004 and 2005 nesting seasons using 3 nest monitoring techniques to identify predators: video cameras, plasticinemore » eggs, and sign from nest using a classification tree analysis. Of 58 nests monitored in 2004 and 286 in 2005, only raccoons (Procyon lotor) and coyotes (Canis latrans) were identified as nest predators. Raccoons were responsible for 22-25% of depredated nests, but were rarely capable of depredating nests that were actively defended by a goose. Coyotes were responsible for 75-78% of all Canada goose nest depredation and were documented killing one adult goose and feeding on several others. The coyote is a top-level predator that had increased in many metropolitan areas in recent years. To determine if coyotes were actively hunting geese or eggs during the nesting season, I analyzed coyote habitat selection between nesting and pre-nesting or post-nesting seasons. Coyote home ranges (95% Minimum Convex Polygon) were calculated for 19 coyotes to examine third order habitat selection related to goose nest abundance. A 100 m buffer (buffer habitat) was created and centered on each waterway edge and contained 90% of all nests. Coyotes showed selection for habitats during all seasons. Buffer habitat was the top ranked habitat in both pre-nesting and nesting seasons, but dropped to third ranked in post-nesting season. Habitat selection across seasons was compared using a repeated measures MANOVA. Habitat selection between pre-nesting and nesting seasons (P=0.72) were similar, while between post-nesting and nesting seasons there was a nearly significant difference (P=0.07). The insignificant change in habitat use across seasons suggests that coyotes did not switch habitat use to take advantage of goose nests. Alternatively, the change in ranking of buffer habitat across seasons suggests that coyotes may have switched habitat use to take advantage of goose nests. The results are not clear as large individual variation between coyotes due to differences in habitat availability, and social status interfere with the results of the analysis. Even though I failed to find strong support for coyotes actively hunting goose nests, they nevertheless were the primary nest predator in the area and may influence Canada goose populations. To determine the potential influence of coyotes on the Canada goose population, I created a Canada goose matrix population model that included variables such as coyote predation on adults and nests as well as coyote influence on nest desertion. Using the base population model I calculated the Canada goose population to be increasing with {lambda} = 1.055. The removal of all coyote influence on the goose population would allow {lambda} to increase to 1.214. Nest predation was the most important factor related to coyotes: the removal of coyote nest predation from the model resulted in a population growth rate {lambda} = 1.157. Modeling results suggest coyotes are serving as a limiting factor for the Canada goose population within the Chicago metropolitan area.« less

Assessing conservation tools for an at-risk shorebird: Feasibility of headstarting for American Oystercatchers Haematopus palliatus

USGS Publications Warehouse

Collins, Samantha A.; Sanders, Felicia J.; Jodice, Patrick G.R.

2016-01-01

Management of threatened and endangered populations of wildlife increasingly relies upon active intervention such as predator control, habitat manipulation, and ex situ breeding or care. One tool that has received consideration for the management of declining or threatened avian populations is headstarting, or the artificial incubation of eggs and subsequent placement of newly hatched chicks in original or foster nests. We assessed the feasibility of implementing a headstarting program for the American Oystercatcher Haematopus palliatus, a species of high conservation concern in the eastern USA. Annual productivity is often low and lost during incubation, suggesting artificial incubation could enhance annual productivity. We used a control-impact approach to assign nests as either control or headstart and measured daily survival rate, success of parents accepting headstarted chicks, attendance patterns and behaviours of parents, and chick survival. We also implemented a transparent scoring process to rate the success of each step and the overall program. Daily survival rates of nests were significantly higher at headstart compared to control nests, and parents continued to incubate when eggs were well secured at nest sites. Attendance patterns and behaviour did not differ between headstart and control parents, and parents readily accepted healthy chicks whether they were returned to original or foster nests. Chick survival and subsequently annual productivity were, however, not higher at headstart compared to control nests suggesting that although we were able to enhance nest survival, low chick survival was still limiting annual productivity. Ultimately, headstarting may be most appropriate for American Oystercatchers where productivity is lost primarily to flooding, predation, or disturbance during the incubation stage but not during the chick-rearing stage. If, for example, high rates of nest loss are due to predators that also may prey upon chicks, then headstarting may not be an effective conservation tool.

Hawksbill satellite-tracking case study: Implications for remigration interval and population estimates

USGS Publications Warehouse

Sartain-Iverson, Autumn R.; Hart, Kristen M.; Fujisaki, Ikuko; Cherkiss, Michael S.; Pollock, Clayton; Lundgren, Ian; Hillis-Starr, Zandy

2016-01-01

Hawksbill sea turtles (Eretmochelys imbricata) are circumtropically distributed and listed as Critically Endangered by the IUCN (Meylan & Donnelly 1999; NMFS & USFWS 1993). To aid in population recovery and protection, the Hawksbill Recovery Plan identified the need to determine demographic information for hawksbills, such as distribution, abundance, seasonal movements, foraging areas (sections 121 and 2211), growth rates, and survivorship (section 2213, NMFS & USFWS 1993). Mark-recapture analyses are helpful in estimating demographic parameters and have been used for hawksbills throughout the Caribbean (e.g., Richardson et al. 1999; Velez-Zuazo et al. 2008); integral to these studies are recaptures at the nesting site as well as remigration interval estimates (Hays 2000). Estimates of remigration intervals (the duration between nesting seasons) are critical to marine turtle population estimates and measures of nesting success (Hays 2000; Richardson et al. 1999). Although hawksbills in the Caribbean generally show natal philopatry and nesting-site fidelity (Bass et al. 1996; Bowen et al. 2007), exceptions to this have been observed for hawksbills and other marine turtles (Bowen & Karl 2007; Diamond 1976; Esteban et al. 2015; Hart et al. 2013). This flexibility in choosing a nesting beach could therefore affect the apparent remigration interval and subsequently, region-wide population counts.

Oh sister, where art thou? Spatial population structure and the evolution of an altruistic defence trait.

PubMed

Pamminger, T; Foitzik, S; Metzler, D; Pennings, P S

2014-11-01

The evolution of parasite virulence and host defences is affected by population structure. This effect has been confirmed in studies focusing on large spatial scales, whereas the importance of local structure is not well understood. Slavemaking ants are social parasites that exploit workers of another species to rear their offspring. Enslaved workers of the host species Temnothorax longispinosus have been found to exhibit an effective post-enslavement defence behaviour: enslaved workers were observed killing a large proportion of the parasites' offspring. As enslaved workers do not reproduce, they gain no direct fitness benefit from this 'rebellion' behaviour. However, there may be an indirect benefit: neighbouring host nests that are related to 'rebel' nests can benefit from a reduced raiding pressure, as a result of the reduction in parasite nest size due to the enslaved workers' killing behaviour. We use a simple mathematical model to examine whether the small-scale population structure of the host species could explain the evolution of this potentially altruistic defence trait against slavemaking ants. We find that this is the case if enslaved host workers are related to nearby host nests. In a population genetic study, we confirm that enslaved workers are, indeed, more closely related to host nests within the raiding range of their resident slavemaker nest, than to host nests outside the raiding range. This small-scale population structure seems to be a result of polydomy (e.g. the occupation of several nests in close proximity by a single colony) and could have enabled the evolution of 'rebellion' by kin selection. © 2014 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

Prospective study of blood metabolites associated with colorectal cancer risk.

PubMed

Shu, Xiang; Xiang, Yong-Bing; Rothman, Nathaniel; Yu, Danxia; Li, Hong-Lan; Yang, Gong; Cai, Hui; Ma, Xiao; Lan, Qing; Gao, Yu-Tang; Jia, Wei; Shu, Xiao-Ou; Zheng, Wei

2018-02-26

Few prospective studies, and none in Asians, have systematically evaluated the relationship between blood metabolites and colorectal cancer risk. We conducted a nested case-control study to search for risk-associated metabolite biomarkers for colorectal cancer in an Asian population using blood samples collected prior to cancer diagnosis. Conditional logistic regression was performed to assess associations of metabolites with cancer risk. In this study, we included 250 incident cases with colorectal cancer and individually matched controls nested within two prospective Shanghai cohorts. We found 35 metabolites associated with risk of colorectal cancer after adjusting for multiple comparisons. Among them, 12 metabolites were glycerophospholipids including nine associated with reduced risk of colorectal cancer and three with increased risk [odds ratios per standard deviation increase of transformed metabolites: 0.31-1.98; p values: 0.002-1.25 × 10 -10 ]. The other 23 metabolites associated with colorectal cancer risk included nine lipids other than glycerophospholipid, seven aromatic compounds, five organic acids and four other organic compounds. After mutual adjustment, nine metabolites remained statistically significant for colorectal cancer. Together, these independently associated metabolites can separate cancer cases from controls with an area under the curve of 0.76 for colorectal cancer. We have identified that dysregulation of glycerophospholipids may contribute to risk of colorectal cancer. © 2018 UICC.

Systemic Lupus Erythematosus is Associated with Uranium Exposure in a Community Living Near a Uranium Processing Plant: A Nested Case-Control Study

PubMed Central

Lu-Fritts, Pai-Yue; Kottyan, Leah C.; James, Judith A.; Xie, Changchung; Buckholz, Jeanette M.; Pinney, Susan M.; Harley, John B.

2014-01-01

Objective Explore the hypothesis that cases of SLE will be found more frequently in community members with high prior uranium exposure in the Fernald Community Cohort (FCC). Methods A nested case control study was performed. The FCC is a volunteer population that lived near a uranium ore processing plant in Fernald, Ohio, USA during plant operation and members were monitored for 18 years. Uranium plant workers were excluded. SLE cases were identified using American College of Rheumatology classification criteria, laboratory testing, and medical record review. Each case was matched to four age-, race-, and sex-matched controls. Sera from potential cases and controls were screened for autoantibodies. Cumulative uranium particulate exposure was calculated using a dosimetry model. Logistic regression with covariates was used to calculate odds ratios (OR) with 95% confidence intervals (CI). Results The FCC includes 4,187 individuals with background uranium exposure, 1,273 with moderate exposure, and 2,756 with higher exposure. SLE was confirmed in 23 of 31 individuals with a lupus ICD9 code, and in 2 of 43 other individuals prescribed hydroxychloroquine. The female:male ratio was 5.25:1. Of the 25 SLE cases, 12 were in the higher exposure group. SLE was associated with higher uranium exposure (OR 3.92, 95% CI 1.131-13.588, p = 0.031). Conclusion High uranium exposure is associated with SLE relative to matched controls in this sample of uranium exposed individuals. Potential explanations for this relationship include possible autoimmune or estrogen effects of uranium, somatic mutation, epigenetic effects, or effects of some other unidentified accompanying exposure. PMID:25103365

Risk of acute coronary events associated with glyburide compared with gliclazide use in patients with type 2 diabetes: a nested case-control study.

PubMed

Abdelmoneim, A S; Eurich, D T; Gamble, J M; Johnson, J A; Seubert, J M; Qiu, W; Simpson, S H

2014-01-01

Sulfonylureas might increase the risk of adverse cardiovascular events; however, emerging evidence suggests there may be important differences amongst these drugs. Some, like glyburide, inhibit KATP channels in the heart and pancreas, while others, like gliclazide, are more likely to selectively inhibit KATP channels in the pancreas. We hypothesized that the risk of acute coronary syndrome (ACS) events would be higher in patients using glyburide compared with gliclazide. This nested case-control study used administrative health data from Alberta, Canada. New users of glyburide or gliclazide aged ≥66 years between 1998 and 2010 were included. Cases were individuals with an ACS-related hospitalization or death. Up to four controls were matched based on birth year, sex, cohort-entry year and follow-up time. Multivariable conditional logistic regression was used to estimate adjusted odds ratios (OR), controlling for baseline drug use and co-morbidities. Our cohort included 7441 gliclazide and 13 884 glyburide users; 51.4% men, mean (s.d.) age 75.5 (6.6) years and mean (s.d.) duration of follow-up 5.5 (4.0) years. A total of 4239 patients had an ACS-related hospitalization or death and were matched to 16 723 controls. Compared with gliclazide use, glyburide use was associated with a higher risk (adjusted OR 1.14; 95% CI 1.06-1.23) of ACS-related hospitalization or death over 5.5 years (number needed to harm: 50). In this observational study, glyburide use was associated with a 14% higher risk of ACS events compared with gliclazide use. Although the difference is small and probably to have implications at the population level rather than the individual patient or clinician, any causal inferences regarding sulfonylurea use and adverse cardiovascular risk should be tested in a large-scale randomized controlled trial. © 2013 John Wiley & Sons Ltd.

Surgery for subacromial impingement syndrome in relation to occupational exposures, lifestyle factors and diabetes mellitus: a nationwide nested case-control study.

PubMed

Dalbøge, Annett; Frost, Poul; Andersen, Johan Hviid; Svendsen, Susanne Wulff

2017-10-01

To estimate the risk of surgery for subacromial impingement syndrome (SIS) in relation to occupational exposures, lifestyle factors and diabetes mellitus. We conducted a case-control study nested in a register-based cohort study of the Danish working population. For each of 3000 first-time cases of surgery for SIS, two age-matched and sex-matched controls were drawn. Cases and controls received a questionnaire on job history and other factors. Job histories were combined with a psychosocial job exposure matrix (JEM) and the updated Shoulder JEM, which provided exposure intensities on measurement scales. Ten-year cumulative exposures to upper arm elevation >90°, repetitive shoulder movements, forceful shoulder exertions and hand-arm vibrations (HAVs) were estimated. We used conditional logistic regression. There were 5396 persons (60%) who answered the questionnaire. For occupational mechanical exposures, the adjusted OR (OR adj ) ranged from 1.9 (95% CI 1.5 to 2.5 for HAVs) to 2.5 (95% CI 1.9 to 3.5 for force) among men and 1.7 (95% CI 1.2 to 2.5 for HAVs) to 2.0 (95% CI 1.3 to 2.9 for force) among women. No statistically significant associations were found for occupational psychosocial factors. Body mass index (BMI) and pack-years of smoking showed OR adj up to 2.0. Diabetes mellitus showed OR adj of 1.5 (95% CI 1.1 to 2.2) for men and 2.2 (95% CI 1.4 to 3.4) for women. Our findings add to the evidence of an increased risk of surgery for SIS in relation to occupational cumulative mechanical exposures, even when an increased risk in relation to BMI, smoking and diabetes mellitus is taken into account. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Social information in nest colonisation and occupancy in a long-lived, solitary breeding bird.

PubMed

Václav, Radovan; Valera, Francisco; Martínez, Teresa

2011-03-01

Recent work increasingly reveals the importance of social information in individual dispersal decisions, population dynamics and conservation. Much of the knowledge gained to date comes from studies on short-lived and/or densely breeding species. In contrast, our understanding of the processes involved in nest-site selection for long-lived, solitary breeding species is insufficient. We increased nest-site availability by nest-box supplementation over a 5-year period in a population of a long-lived, solitary, secondary-cavity nesting bird, the European roller Coracias garrulus, breeding in natural cavities and human constructions. We tested the nest limitation and the inadvertent conspecific social information hypothesis in order to study the dynamics and mechanisms of abandonment of previously used nests and the colonisation of new ones. Our data lend support to the nest-limitation hypothesis both in terms of quantity-population and the size of breeding clusters increased, and suitability--the majority of pairs used and re-occupied nest-boxes. Nevertheless, the use of natural cavities did not decrease after 5 years. At the between-patch scale, rollers were revealed to colonise nest-boxes based on conspecific social attraction, namely distance to the nearest neighbour in the same season. Despite the unpredictability of patch productivity, at the within--patch scale, the selection of previously unoccupied cavities was consistent with the performance-based conspecific attraction hypothesis. Philopatry could account for the repeated use of cavities, because nests that were used for two successive years were more likely to also be reused in the subsequent season.

Disentangling endogenous versus exogenous pattern formation in spatial ecology: a case study of the ant Azteca sericeasur in southern Mexico.

PubMed

Li, Kevin; Vandermeer, John H; Perfecto, Ivette

2016-05-01

Spatial patterns in ecology can be described as reflective of environmental heterogeneity (exogenous), or emergent from dynamic relationships between interacting species (endogenous), but few empirical studies focus on the combination. The spatial distribution of the nests of Azteca sericeasur, a keystone tropical arboreal ant, is thought to form endogenous spatial patterns among the shade trees of a coffee plantation through self-regulating interactions with controlling agents (i.e. natural enemies). Using inhomogeneous point process models, we found evidence for both types of processes in the spatial distribution of A. sericeasur. Each year's nest distribution was determined mainly by a density-dependent relationship with the previous year's lagged nest density; but using a novel application of a Thomas cluster process to account for the effects of nest clustering, we found that nest distribution also correlated significantly with tree density in the later years of the study. This coincided with the initiation of agricultural intensification and tree felling on the coffee farm. The emergence of this significant exogenous effect, along with the changing character of the density-dependent effect of lagged nest density, provides clues to the mechanism behind a unique phenomenon observed in the plot, that of an increase in nest population despite resource limitation in nest sites. Our results have implications in coffee agroecological management, as this system provides important biocontrol ecosystem services. Further research is needed, however, to understand the effective scales at which these relationships occur.

Trimethoprim/sulfamethoxazole-induced phenytoin toxicity in the elderly: a population-based study

PubMed Central

Antoniou, Tony; Gomes, Tara; Mamdani, Muhammad M; Juurlink, David N

2011-01-01

AIMS Pharmacokinetic studies suggest that trimethoprim (TMP) can inhibit the hepatic metabolism of phenytoin, but the clinical relevance of this is uncertain. We studied the risk of phenytoin toxicity following the prescription of trimethoprim/sulfamethoxazole (TMP/SMX), a commonly used antibiotic, among elderly patients receiving phenytoin. METHODS We conducted a population-based, nested case–control study of a cohort of Ontario residents aged 66 years of age or older treated with phenytoin over a 17-year period (April 1 1992 to March 31 2009). Within this group, case patients were those hospitalized with phenytoin toxicity. For each case, we identified up to four control patients from the same cohort, matched for age and sex, and determined the odds ratio (OR) for the association between phenytoin toxicity and receipt of TMP/SMX in the preceding 30 days. RESULTS Among 58 429 elderly patients receiving phenytoin during the study period, we identified 796 case patients hospitalized for phenytoin toxicity and 3148 matched controls. Following multivariable adjustment for potential confounders, we observed a more than doubling of the risk of phenytoin toxicity following the receipt of TMP/SMX [adjusted OR 2.11, 95% confidence interval (CI) 1.24, 3.60]. In contrast, we observed no such risk with amoxicillin, an antibiotic with similar indications but not expected to interact with phenytoin (adjusted OR 1.12, 95% CI 0.64, 1.98). CONCLUSION Among older patients receiving phenytoin, treatment with TMP/SMX is associated with a more than twofold increase in the risk of phenytoin toxicity. When clinically appropriate, alternate antibiotics should be considered for these patients. PMID:21395647

A polymorphism in the glucokinase gene that raises plasma fasting glucose, rs1799884, is associated with diabetes mellitus and prostate cancer: findings from a population-based, case-control study (the ProtecT study)

PubMed Central

Murad, Ali S; Smith, George Davey; Lewis, Sarah J; Cox, Angela; Donovan, Jenny L; Neal, David E; Hamdy, Freddie C; Martin, Richard M

2010-01-01

Epidemiological studies have identified a positive association between prostate cancer and recent onset type 2 diabetes mellitus but an increasingly inverse association with greater duration of type 2 diabetes. The mecha- nisms underlying these paradoxical associations are not clear. A single nucleotide polymorphism in the glucokinase gene, rs1799884, is associated with higher circulating plasma fasting glucose and with an increased risk of type 2 diabetes. We report a case-control study nested within the population-based Prostate testing for cancer and Treatment (ProtecT) study ISRCTN20141297. Men aged 50-69 years based around 9 UK cities were invited for a prostate specific antigen (PSA) test between June 2002 and November 2006. 1,551 cases and 2,993 controls were geno-typed. We observed suggestive evidence for a positive association between the AA variant rs1799884 and PSA-detected prostate cancer (ORAA V GG= 1.40, 95% CI= 0.95 to 2.07). There was little evidence that this effect was greater for more advanced stage/ grade cancers (ORAA V GG= 1.78, 95% CI= 0.99 to 3.21) versus less advanced cancers (ORAA V GG= 1.23, 95% CI= 0.77 to 1.94) (p for interaction = 0.33). The rs1799884 genotype was not associated with PSA concentration, suggesting that any effect on prostate cancer risk is not attributable to PSA detection bias. Our results provide suggestive evidence for a link between a genotype associated with type 2 diabetes mellitus and PSA-detected prostate cancer. We hypothesize that hyperglycaemia may be important in mediating this relationship. PMID:21537389

Integrating info-gap decision theory with robust population management: a case study using the Mountain Plover.

PubMed

van der Burg, Max Post; Tyre, Andrew J

2011-01-01

Wildlife managers often make decisions under considerable uncertainty. In the most extreme case, a complete lack of data leads to uncertainty that is unquantifiable. Information-gap decision theory deals with assessing management decisions under extreme uncertainty, but it is not widely used in wildlife management. So too, robust population management methods were developed to deal with uncertainties in multiple-model parameters. However, the two methods have not, as yet, been used in tandem to assess population management decisions. We provide a novel combination of the robust population management approach for matrix models with the information-gap decision theory framework for making conservation decisions under extreme uncertainty. We applied our model to the problem of nest survival management in an endangered bird species, the Mountain Plover (Charadrius montanus). Our results showed that matrix sensitivities suggest that nest management is unlikely to have a strong effect on population growth rate, confirming previous analyses. However, given the amount of uncertainty about adult and juvenile survival, our analysis suggested that maximizing nest marking effort was a more robust decision to maintain a stable population. Focusing on the twin concepts of opportunity and robustness in an information-gap model provides a useful method of assessing conservation decisions under extreme uncertainty.

Use of Proton Pump inhibitors is Associated with Fractures in Young Adults: A Population-Based Study

PubMed Central

Freedberg, Daniel E.; Haynes, Kevin; Denburg, Michelle R.; Zemel, Babette S.; Leonard, Mary B.; Abrams, Julian A.; Yang, Yu-Xiao

2015-01-01

Purpose Proton pump inhibitors (PPIs) are associated with fracture in adults with osteoporosis. Because PPI therapy may interfere with bone accrual and attainment of peak bone mineral density, we studied the association between use of PPIs and fracture in children and young adults. Methods We conducted a population-based, case-control study nested within records from general medical practices from 1994 to 2013. Participants were 4–29 years old with ≥1 year of follow-up who lacked chronic conditions associated with use of long-term acid suppression. Cases of fracture were defined as the first incident fracture at any site. Using incidence density sampling, cases were matched with up to 5 controls by age, sex, medical practice, and start of follow-up. PPI exposure was defined as 180 or more cumulative doses of PPIs. Conditional logistic regression was used to estimate the odds ratio and confidence interval for use of PPIs and fracture. Results We identified 124,799 cases and 605,643 controls. The adjusted odds ratio for the risk of fracture associated with PPI exposure was 1.13 (95% CI 0.92 to 1.39) among children aged < 18 years old and 1.39 (95% CI 1.26 to 1.53) among young adults aged 18–29 years old. In young adults but not children, we observed a dose-response effect with increased total exposure to PPIs (p for trend <.001). Conclusions PPI use was associated with fracture in young adults but overall evidence did not support a PPI-fracture relationship in children. Young adults who use PPIs should be cautioned regarding potentially increased risk for fracture, even if they lack traditional fracture risk factors. PMID:25986385

Fetal Growth and Childhood Cancer: A Population-Based Study

PubMed Central

Sørensen, Henrik Toft; Grotmol, Tom; Engeland, Anders; Stephansson, Olof; Gissler, Mika; Tretli, Steinar; Troisi, Rebecca

2013-01-01

OBJECTIVE: The etiology of childhood cancers is largely unknown. Studies have suggested that birth characteristics may be associated with risk. Our goal was to evaluate the risk of childhood cancers in relation to fetal growth. METHODS: We conducted a case-control study nested within Nordic birth registries. The study included cancer cases diagnosed in Denmark, Finland, Norway, and Sweden among children born from 1967 to 2010 and up to 10 matched controls per case, totaling 17 698 cases and 172 422 controls. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were derived from conditional logistic regression. RESULTS: Risks of all childhood cancers increased with increasing birth weight (Ptrend ≤ .001). Risks of acute lymphoid leukemia and Wilms tumor were elevated when birth weight was >4000 g and of central nervous system tumors when birth weight was >4500 g. Newborns large for gestational age were at increased risk of Wilms tumor (OR: 2.1 [95% CI: 1.2–3.6]) and connective/soft tissue tumors (OR: 2.1 [95% CI: 1.1–4.4]). In contrast, the risk of acute myeloid leukemia was increased among children born small for gestational age (OR: 1.8 [95% CI: 1.1–3.1]). Children diagnosed with central nervous system tumors at <1 year of age had elevated risk with increasing head circumference (Ptrend < .001). Those with head circumference >39 cm had the highest risk (OR: 4.7 [95% CI: 2.5–8.7]). CONCLUSIONS: In this large, Nordic population-based study, increased risks for several childhood tumors were associated with measures of fetal growth, supporting the hypothesis that tumorigenesis manifesting in childhood is initiated in utero. PMID:24167169

Air Pollution and Pulmonary Tuberculosis: A Nested Case–Control Study among Members of a Northern California Health Plan

PubMed Central

Smith, Geneé S.; Van Den Eeden, Stephen K.; Garcia, Cynthia; Shan, Jun; Baxter, Roger; Herring, Amy H.; Richardson, David B.; Van Rie, Annelies; Emch, Michael; Gammon, Marilie D.

2016-01-01

Background: Ecologic analyses, case–case comparisons, and animal experiments suggest positive associations between air pollution and tuberculosis. Objectives: We evaluated this hypothesis in a large sample, which yielded results that are applicable to the general population. Methods: We conducted a case–control study nested within a cohort of Kaiser Permanente of Northern California members. All active pulmonary tuberculosis (TB) cases newly diagnosed between 1996 and 2010 (n = 2,309) were matched to two controls (n = 4,604) by age, sex, and race/ethnicity on the index date corresponding with the case diagnosis date. Average individual-level concentrations of carbon monoxide (CO), nitrogen dioxide (NO2), sulfur dioxide (SO2), ozone (O3), and particulate matter with aerodynamic diameter ≤ 2.5 μm (PM2.5) and 10 μm (PM10) for 2 years before diagnosis/entry into the study were estimated using measurements from the California Air Resources Board monitor closest to the participant’s residence. Results: In single-pollutant adjusted conditional logistic regression models, the pulmonary TB odds ratios (95% confidence intervals) for the highest quintile (vs. lowest) were 1.50 (95% CI: 1.15, 1.95) for CO and 1.42 (95% CI: 1.10, 1.84) for NO2. Corresponding estimates were higher among never [1.68 (95% CI: 1.26, 2.24)] than ever [1.19 (95% CI: 0.74, 1.92)] smokers for CO. In contrast, for NO2, estimates were higher among ever [1.81 (95% CI: 1.13, 2.91)] than never [1.29 (95% CI: 0.97, 1.71)] smokers. O3 was inversely associated for smokers [0.66 (95% CI: 0.43, 1.02)] and never smokers [0.65 (95% CI: 0.52, 0.81)]. No other consistent patterns were observed. Conclusions: In this first, to our knowledge, U.S. nested case–control study on air pollution and pulmonary TB, we observed positive associations with ambient CO and NO2, which require confirmation. Citation: Smith GS, Van Den Eeden SK, Garcia C, Shan J, Baxter R, Herring AH, Richardson DB, Van Rie A, Emch M, Gammon MD. 2016. Air pollution and pulmonary tuberculosis: a nested case-control study among members of a Northern California health plan. Environ Health Perspect 124:761–768; http://dx.doi.org/10.1289/ehp.1408166 PMID:26859438

Utility of genetic and non-genetic risk factors in predicting coronary heart disease in Singaporean Chinese.

PubMed

Chang, Xuling; Salim, Agus; Dorajoo, Rajkumar; Han, Yi; Khor, Chiea-Chuen; van Dam, Rob M; Yuan, Jian-Min; Koh, Woon-Puay; Liu, Jianjun; Goh, Daniel Yt; Wang, Xu; Teo, Yik-Ying; Friedlander, Yechiel; Heng, Chew-Kiat

2017-01-01

Background Although numerous phenotype based equations for predicting risk of 'hard' coronary heart disease are available, data on the utility of genetic information for such risk prediction is lacking in Chinese populations. Design Case-control study nested within the Singapore Chinese Health Study. Methods A total of 1306 subjects comprising 836 men (267 incident cases and 569 controls) and 470 women (128 incident cases and 342 controls) were included. A Genetic Risk Score comprising 156 single nucleotide polymorphisms that have been robustly associated with coronary heart disease or its risk factors ( p < 5 × 10 -8 ) in at least two independent cohorts of genome-wide association studies was built. For each gender, three base models were used: recalibrated Adult Treatment Panel III (ATPIII) Model (M 1 ); ATP III model fitted using Singapore Chinese Health Study data (M 2 ) and M 3 : M 2 + C-reactive protein + creatinine. Results The Genetic Risk Score was significantly associated with incident 'hard' coronary heart disease ( p for men: 1.70 × 10 -10 -1.73 × 10 -9 ; p for women: 0.001). The inclusion of the Genetic Risk Score in the prediction models improved discrimination in both genders (c-statistics: 0.706-0.722 vs. 0.663-0.695 from base models for men; 0.788-0.790 vs. 0.765-0.773 for women). In addition, the inclusion of the Genetic Risk Score also improved risk classification with a net gain of cases being reclassified to higher risk categories (men: 12.4%-16.5%; women: 10.2% (M 3 )), while not significantly reducing the classification accuracy in controls. Conclusions The Genetic Risk Score is an independent predictor for incident 'hard' coronary heart disease in our ethnic Chinese population. Inclusion of genetic factors into coronary heart disease prediction models could significantly improve risk prediction performance.

Non-Steroidal Anti-Inflammatory Drug Use and the Risk of Acute Myocardial Infarction in the General German Population: A Nested Case-Control Study.

PubMed

Thöne, Kathrin; Kollhorst, Bianca; Schink, Tania

2017-09-01

Use of non-steroidal anti-inflammatory drugs (NSAIDs) has been associated with an increased relative risk of acute myocardial infarction (AMI), but the label warnings refer particularly to patients with cardiovascular risk factors. The magnitude of relative AMI risk for patients with and without cardiovascular risk factors varies between studies depending on the drugs and doses studied. The aim of our study was to estimate population-based relative AMI risks for individual and widely used NSAIDs, for a cumulative amount of NSAID use, and for patients with and without a prior history of cardiovascular risk factors. Based on data from the German Pharmacoepidemiological Research Database (GePaRD) of about 17 million insurance members from four statutory health insurance providers, for the years 2004-2009, a nested case-control study was conducted within a cohort of 3,476,931 new NSAID users classified into current, recent, or past users. Up to 100 controls were matched to each case by age, sex, and length of follow-up using risk set sampling. Multivariable conditional logistic regression was applied to estimate odds ratios (ORs) and 95% confidence intervals (CIs). Duration of NSAID use was calculated by the cumulative amount of dispensed defined daily doses (DDDs), and stratified analyses were conducted for potential effect modifiers. Overall, 17,236 AMI cases were matched to 1,714,006 controls. Elevated relative AMI risks were seen for current users of fixed combinations of diclofenac with misoprostol (OR 1.76, 95% CI 1.26-2.45), indometacin (1.69, 1.22-2.35), ibuprofen (1.54, 1.43-1.65), etoricoxib (1.52, 1.24-1.87), and diclofenac (1.43, 1.34-1.52) compared with past use. A low cumulative NSAID amount was associated with a higher relative AMI risk for ibuprofen, diclofenac, and indometacin. The relative risk associated with current use of diclofenac, fixed combinations of diclofenac with misoprostol, etoricoxib, and ibuprofen was highest in the younger age group (<60 years) and similar for patients with or without major cardiovascular risk factors. Relative AMI risk estimates differed among the 15 investigated individual NSAIDs. Diclofenac and ibuprofen, the most frequently used NSAIDs, were associated with a 40-50% increased relative risk of AMI, even for low cumulative NSAID amounts. The relative AMI risk in patients with and without cardiovascular risk factors was similarly elevated.

Leukemia and brain tumors in Norwegian railway workers, a nested case-control study.

PubMed

Tynes, T; Jynge, H; Vistnes, A I

1994-04-01

In an attempt to assess whether exposure to electromagnetic fields on Norwegian railways induces brain tumors or leukemia, the authors conducted a nested case-control study of railway workers based on incident cases from the Cancer Registry of Norway in a cohort of 13,030 male Norwegian railway workers who had worked on either electric or non-electric railways. The cohort comprised railway line, outdoor station, and electricity workers. The case series comprised 39 men with brain tumors and 52 men with leukemia (follow-up, 1958-1990). Each case was matched on age with four or five controls selected from the same cohort. The exposure of each study subject to electric and magnetic fields was evaluated from cumulative exposure measures based on present measurements and historical data. Limited information on potential confounders such as creosote, solvents, and herbicides was also collected; information on whether the subject had smoked was obtained by interviews with the subjects or work colleagues. The case-control analysis showed that men employed on electric railways, compared with non-electric ones, had an odds ratio for leukemia of 0.70 (adjusted for smoking) and an odds ratio for brain tumor of 0.87. No significant trend was shown for exposure to either magnetic or electric fields. These results do not support an association between exposure to 16 2/3-Hertz electric or magnetic fields and the risk for leukemia or brain tumors.

Oral bisphosphonates do not increase the risk of severe upper gastrointestinal complications: a nested case–control study

PubMed Central

2014-01-01

Background Data on the effect of oral bisphosphonates (BPs) on risk of upper gastrointestinal complications (UGIC) are conflicting. We conducted a large population-based study from a network of Italian healthcare utilization databases aimed to assess the UGIC risk associated with use of BPs in the setting of secondary prevention of osteoporotic fractures. Methods A nested case–control study was carried out within a cohort of 68,970 patients aged 45 years or older, who have been hospitalized for osteoporotic fracture from 2003 until 2005. Cases were the 804 patients who experienced hospitalization for UGIC until 2007. Up to 20 controls were randomly selected for each case. Conditional logistic regression model was used to estimate odds ratio (OR) associated with current and past use of BPs (i.e. for drug dispensation within 30 days and over 31 days prior the outcome onset, respectively) after adjusting for several covariates. Results Compared with patients who did not use BPs, current and past users had OR (and 95% confidence interval) of 0.86 (0.60 to 1.22) and 1.07 (0.80 to 1.44) respectively. There was no difference in the ORs estimated according with BPs type (alendronate or risedronate) and regimen (daily or weekly), nor with co-therapies and comorbidities. Conclusions Further evidence that BPs dispensed for secondary prevention of osteoporotic fractures are not associated with increased risk of severe gastrointestinal complications is supplied from this study. Further research is required to clarify the role BPs and other drugs of co-medication in inducing UGIC. PMID:24397769

Occupational exposure to asbestos and risk of cholangiocarcinoma: a population-based case-control study in four Nordic countries.

PubMed

Farioli, Andrea; Straif, Kurt; Brandi, Giovanni; Curti, Stefania; Kjaerheim, Kristina; Martinsen, Jan Ivar; Sparen, Pär; Tryggvadottir, Laufey; Weiderpass, Elisabete; Biasco, Guido; Violante, Francesco Saverio; Mattioli, Stefano; Pukkala, Eero

2018-03-01

To assess the association between occupational exposure to asbestos and the risk of cholangiocarcinoma (CC). We conducted a case-control study nested in the Nordic Occupational Cancer (NOCCA) cohort. We studied 1458 intrahepatic CC (ICC) and 3972 extrahepatic CC (ECC) cases occurring among subjects born in 1920 or later in Finland, Iceland, Norway and Sweden. Each case was individually matched by birth year, gender and country to five population controls. The cumulative exposure to asbestos (measured in fibres (f)/ml × years) was assessed by applying the NOCCA job-exposure matrix to data on occupations collected during national population censuses (conducted in 1960, 1970, 1980/81 and 1990). Odds ratios (OR) and 95% CI were estimated using conditional logistic regression models adjusted by printing industry work. We observed an increasing risk of ICC with cumulative exposure to asbestos: never exposed, OR 1.0 (reference category); 0.1-4.9 f/mL × years, OR 1.1 (95% CI 0.9 to 1.3); 5.0-9.9 f/mL × years, OR 1.3 (95% CI 0.9 to 2.1); 10.0-14.9 f/mL × years, OR 1.6 (95% CI 1.0 to 2.5); ≥15.0 f/mL × years, OR 1.7 (95% CI 1.1 to 2.6). We did not observe an association between cumulative asbestos exposure and ECC. Our study provides evidence that exposure to asbestos might be a risk factor for ICC. Our findings also suggest that the association between ECC and asbestos is null or weaker than that observed for ICC. Further studies based on large industrial cohorts of asbestos workers and possibly accounting for personal characteristics and clinical history are needed. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Pernicious anemia and colorectal cancer risk - A nested case-control study.

PubMed

Boursi, Ben; Mamtani, Ronac; Haynes, Kevin; Yang, Yu-Xiao

2016-11-01

Hypergastrinemia was shown to stimulate colonic epithelial cell proliferation. To evaluate the association between pernicious anemia (PA), a disease with hypergastrinemia, and colorectal cancer (CRC) risk. We conducted a nested case-control study within a large database from the UK. Cases were defined as all individuals in the cohort with at least one medical code for CRC. Controls were selected based on incidence-density sampling. For each case, up to four eligible controls were matched on age at diagnosis, sex, practice-site, and both duration and calendar time of follow-up. Exposure of interest was diagnosis of PA prior to CRC diagnosis date. The primary analysis was a multivariable conditional logistic regression. Our study included 22,098 CRC cases and 85,969 matched controls. We identified 154 (0.70%) cases and 563 (0.65%) controls with past history of PA. The adjusted OR for the association between PA and CRC risk was 1.02 (95% CI 0.85-1.22). There was no difference in the results after stratification according to sex. In a sensitivity analysis only among individuals without chronic use of proton pump inhibitors (PPIs) the adjusted OR was 1.14 (95% CI 0.90-1.45). There was no association between duration of PA and CRC risk. PA is not associated with higher CRC risk. Copyright © 2016. Published by Elsevier Ltd.

Reduction in sea lamprey hatching success due to release of sterilized males

USGS Publications Warehouse

Bergstedt, Roger A.; McDonald, Rodney B.; Twohey, Michael B.; Mullett, Katherine M.; Young, Robert J.; Heinrich, John W.

2003-01-01

Male sea lampreys (Petromyzon marinus), sterilized by injection with bisazir, were released in Lake Superior tributaries from 1991 to 1996 and exclusively in the St. Marys River (the outflow from Lake Superior to Lake Huron) since 1997 as an alternative to chemical control. To determine effectiveness in reducing reproductive potential through the time of hatch, males were observed on nests and egg viability was determined in nests in selected Lake Superior tributaries and the St. Marys River. The proportions of sterilized males observed on nests were not significantly different than their estimated proportion in the population for all streams and years combined or for the St. Marys River alone. It was concluded that sterilized males survive, appear on the spawning grounds, and nest at near their estimated proportion in the population. There was a significant reduction in egg viability corresponding with release of sterilized males for all streams and years combined or for the St. Marys River alone. In the St. Marys River from 1993 to 2000, the percent reduction in egg viability was significantly correlated with the observed proportion of sterile males on nests. It was further concluded that sterilized males remain sterile through nesting and attract and mate with females. Reduction in reproductive potential in the St. Marys River due to both removal of females by traps and sterile-male-release ranged from 34 to 92% from 1993 to 2001 and averaged 64%. From 1999 to 2001, when the program stabilized, reductions ranged from 71 to 92% and averaged 81%. The current release of sterile males in the St. Marys River effectively reduced reproductive potential through the time of hatch and did so near theoretical levels based on numbers released, estimates of population size, and the assumptions of full sterility and competitiveness.

Evaluation of Canada goose sterilization for population control

USGS Publications Warehouse

Converse, Kathryn A.; Kennelly, James J.

1994-01-01

We evaluated the vasectomy of 72 male Canada geese as a method to control growing populations of nuisance geese in Westchester County, New York. Thirty-three of the vasectomized males paired with a female and were located during ≥1 breeding seasons; 7 treated males were not seen following surgery. The remaining 32 males were never observed paired with a female during the breeding season. Of 56 nesting attempts by the 33 pairs in ≥1 breeding seasons, 84% of the nests were unsuccessful. Fidelity to nest sites during the second and third breeding seasons occurred for 17 of the 18 vasectomized males and their females that were observed for ≥2 seasons. The results suggest that male sterilization may reduce productivity of nuisance Canada geese providing one carefully selects areas and flocks suitable for this type of control.

Dairy products and risk of hepatocellular carcinoma: the European Prospective Investigation into Cancer and Nutrition.

PubMed

Duarte-Salles, Talita; Fedirko, Veronika; Stepien, Magdalena; Trichopoulou, Antonia; Bamia, Christina; Lagiou, Pagona; Lukanova, Annekatrin; Trepo, Elisabeth; Overvad, Kim; Tjønneland, Anne; Halkjaer, Jytte; Boutron-Ruault, Marie-Christine; Racine, Antoine; Cadeau, Claire; Kühn, Tilman; Aleksandrova, Krasimira; Trichopoulos, Dimitrios; Tsiotas, Konstantinos; Boffetta, Paolo; Palli, Domenico; Pala, Valeria; Tumino, Rosario; Sacerdote, Carlotta; Panico, Salvatore; Bueno-de-Mesquita, H B as; Dik, Vincent K; Peeters, Petra H; Weiderpass, Elisabete; Torhild Gram, Inger; Hjartåker, Anette; Ramón Quirós, Jose; Fonseca-Nunes, Ana; Molina-Montes, Esther; Dorronsoro, Miren; Navarro Sanchez, Carmen; Barricarte, Aurelio; Lindkvist, Björn; Sonestedt, Emily; Johansson, Ingegerd; Wennberg, Maria; Khaw, Kay-Tee; Wareham, Nick; Travis, Ruth C; Romieu, Isabelle; Riboli, Elio; Jenab, Mazda

2014-10-01

Intake of dairy products has been associated with risk of some cancers, but findings are often inconsistent and information on hepatocellular carcinoma (HCC) risk is limited, particularly from prospective settings. The aim of our study was to investigate the association between consumption of total and specific dairy products (milk/cheese/yogurt) and their components (calcium/vitamin D/fats/protein), with first incident HCC (N(cases) = 191) in the European Prospective Investigation into Cancer and Nutrition cohort, including a nested case-control subset (N(cases) = 122) with the assessment of hepatitis B virus/hepatitis C virus infections status, liver damage and circulating insulin-like growth factor (IGF)-I levels. For cohort analyses, multivariable-adjusted Cox proportional hazard models were used to estimate hazard ratios (HRs) and 95% confidence intervals (95% CI). For nested case-control analyses, conditional logistic regression was used to calculate odds ratios and 95% CI. A total of 477,206 participants were followed-up for an average of 11 years (person-years follow-up = 5,415,385). In the cohort study, a significant positive HCC risk association was observed for total dairy products (highest vs. lowest tertile, HR = 1.66, 95% CI: 1.13-2.43; p(trend) = 0.012), milk (HR = 1.51, 95% CI: 1.02-2.24; p(trend) = 0.049), and cheese (HR = 1.56, 95% CI: 1.02-2.38; p(trend) = 0.101), but not yogurt (HR = 0.94, 95% CI: 0.65-1.35). Dietary calcium, vitamin D, fat and protein from dairy sources were associated with increased HCC risk, whereas the same nutrients from nondairy sources showed inverse or null associations. In the nested case-control study, similar results were observed among hepatitis-free individuals. Results from this large prospective cohort study suggest that higher consumption of dairy products, particularly milk and cheese, may be associated with increased HCC risk. Validation of these findings in other populations is necessary. Potential biologic mechanisms require further exploration. © 2014 UICC.

Effect of statin on hepatocellular carcinoma in patients with type 2 diabetes: A nationwide nested case-control study.

PubMed

Kim, Gyuri; Jang, Suk-Yong; Han, Eugene; Lee, Yong-Ho; Park, Se-Young; Nam, Chung Mo; Kang, Eun Seok

2017-02-15

Relationship on new statin use and the risk of hepatocellular carcinoma (HCC) in patients with incident type 2 diabetes mellitus (T2DM), who might be at the risk of developing HCC, is uncertained. A nationwide population-based nested case-control study was conducted within the National Health Insurance Service National Sample Cohort 2002-2013 in Korea. Newly prescribed statin after newly diagnosed T2DM was defined as statin use. Controls were matched to case patients on age, sex, follow-up time, and the date of diabetes diagnosis at a five-to-one ratio. Odds ratios (ORs) for associations of statin use with HCC were calculated using conditional logistic regression. After at least a 5-year HCC-free period, there were 229 incident HCC cases and 1,145 matched controls from 47,738 patients with incident diabetes. Of these 229 incident HCC cases, 27 (11.8%) were statin users, whereas 378 (33.0%) were statin users among 1,145 controls. Statin use was associated with a reduced risk of HCC development (adjusted OR [AOR]= 0.36, 95% confidence interval [CI] 0.22-0.60) after adjustment for chronic viral hepatitis, liver cirrhosis, alcoholic liver disease, previous cancer, aspirin use, insulin use, sulfonylurea use, metformin use, thiazolidinedione use, history of chronic obstructive pulmonary disease, Charlson comorbidity score, household income level, and residential area. Risk reduction was accentuated with an increase of cumulative defined daily doses (cDDD) compared with non-users (AORs 0.53, 0.36, 0.32, and 0.26 in ≤60, 60-180, 181-365, and >365cDDD, respectively; P for trend <0.0001). The risk reduction was apparent in the presence of liver disease (AOR = 0.27, 95% CI 0.14-0.50), including heterogeneous groups of clinical diagnosis of liver disease, but not significant in the absence of liver disease (AOR = 0.64, 95% CI 0.32-1.29). Among patients with new onset T2DM, statin use before HCC diagnosis may have a beneficial inhibitory effect on HCC development in a dose-dependent manner, especially in individuals with liver disease. © 2016 UICC.

Mitigating road mortality of diamond-backed terrapins (Malaclemy's terrapin) with hybrid barriers at crossing hot spots

USGS Publications Warehouse

Crawford, Brian A.; Moore, Clinton; Norton, Terry M.; Maerz, John C.

2017-01-01

Roads represent a pervasive feature on most landscapes that can pose multiple threats to wildlife populations and substantial challenges for management. To be effective, management strategies must often target where threats are most concentrated. Road mortality and nest predation are well-documented threats to Diamond-backed Terrapins (Malaclemys terrapin) across the majority of their range, including the 8.7-km causeway to Jekyll Island, Georgia, USA, where both are predicted to contribute to population declines if left unmitigated. From 2009 to 2014, we used intensive road surveying to identify spatial peaks (hot spots) of terrapin crossing activity and road mortality and exploit these as targets for management. In 2011, we deployed a hybrid barrier composed of nest boxes, which were designed to prevent terrapins from accessing the road and mitigate nest predation, at one hot spot while leaving two other hot spots unmanaged. We evaluated the impact of the barrier on terrapin emergences on the causeway under a Before-After-Control-Impact (BACI) design, and a companion study evaluated the effects of nest boxes on nest predation rates. We estimated a 57% reduction in annual terrapin emergences at the barrier site compared to no measurable change at control hot spots. Our findings support the use of hybrid barriers for simultaneously addressing road mortality and nest predation for other terrapin populations at risk to these threats. Our approach highlights the need to design feasible but robust management strategies that target spatial peaks of road mortality while addressing additional threats contributing to population declines of terrapins and other species.

Invasive rats strengthen predation pressure on bird eggs in a South Pacific island rainforest

PubMed Central

Bourguet, Edouard; De Meringo, Hélène; Millon, Alexandre; Vidal, Eric

2017-01-01

Abstract Invasive rats (Rattus spp.) are known to have pervasive impacts on island birds, particularly on their nesting success. To conserve or restore bird populations, numerous invasive rat control or eradication projects are undertaken on islands worldwide. However, such projects represent a huge investment and the decision-making process requires proper assessment of rat impacts. Here, we assessed the influence of two sympatric invasive rats (Rattus rattus and R. exulans) on native bird eggs in a New Caledonian rainforest, using artificial bird-nest monitoring. A total of 178 artificial nests containing two eggs of three different sizes were placed either on the ground or 1.5 m high and monitored at the start of the birds’ breeding season. Overall, 12.4% of the nests were depredated during the first 7 days. At site 1, where nests were monitored during 16 days, 41.8% of the nests were depredated. The main predator was the native crow Corvus moneduloides, responsible for 62.9% of the overall predation events. Rats were responsible for only 22.9% of the events, and ate only small and medium eggs at both heights. Our experiment suggests that in New Caledonia, predation pressure by rats strengthens overall bird-nest predation, adding to that by native predators. Experimental rat control operations may allow reduced predation pressure on nests as well as the recording of biodiversity responses after rat population reduction. PMID:29492018

Invasive rats strengthen predation pressure on bird eggs in a South Pacific island rainforest.

PubMed

Duron, Quiterie; Bourguet, Edouard; De Meringo, Hélène; Millon, Alexandre; Vidal, Eric

2017-12-01

Invasive rats ( Rattus spp.) are known to have pervasive impacts on island birds, particularly on their nesting success. To conserve or restore bird populations, numerous invasive rat control or eradication projects are undertaken on islands worldwide. However, such projects represent a huge investment and the decision-making process requires proper assessment of rat impacts. Here, we assessed the influence of two sympatric invasive rats ( Rattus rattus and R. exulans ) on native bird eggs in a New Caledonian rainforest, using artificial bird-nest monitoring. A total of 178 artificial nests containing two eggs of three different sizes were placed either on the ground or 1.5 m high and monitored at the start of the birds' breeding season. Overall, 12.4% of the nests were depredated during the first 7 days. At site 1, where nests were monitored during 16 days, 41.8% of the nests were depredated. The main predator was the native crow Corvus moneduloides , responsible for 62.9% of the overall predation events. Rats were responsible for only 22.9% of the events, and ate only small and medium eggs at both heights. Our experiment suggests that in New Caledonia, predation pressure by rats strengthens overall bird-nest predation, adding to that by native predators. Experimental rat control operations may allow reduced predation pressure on nests as well as the recording of biodiversity responses after rat population reduction.

A Nested Case-Control Study of Luteinizing Hormone Variants and Risk of Breast Cancer

DTIC Science & Technology

1999-10-01

study has addressed the relationship of the presence of the variant LH to clinical and hormonal parameters among women with polycystic ovaries as...compared to healthy subjects (6). In this study, the variant was appreciably more frequent in obese women with polycystic ovaries than in normal women...immunological LH- 13-subunit variant in a UK population of healthy women and women with polycystic ovary syndrome. Clin Endocrinol. 1995; 43:297-303

A hierarchical nest survival model integrating incomplete temporally varying covariates

PubMed Central

Converse, Sarah J; Royle, J Andrew; Adler, Peter H; Urbanek, Richard P; Barzen, Jeb A

2013-01-01

Nest success is a critical determinant of the dynamics of avian populations, and nest survival modeling has played a key role in advancing avian ecology and management. Beginning with the development of daily nest survival models, and proceeding through subsequent extensions, the capacity for modeling the effects of hypothesized factors on nest survival has expanded greatly. We extend nest survival models further by introducing an approach to deal with incompletely observed, temporally varying covariates using a hierarchical model. Hierarchical modeling offers a way to separate process and observational components of demographic models to obtain estimates of the parameters of primary interest, and to evaluate structural effects of ecological and management interest. We built a hierarchical model for daily nest survival to analyze nest data from reintroduced whooping cranes (Grus americana) in the Eastern Migratory Population. This reintroduction effort has been beset by poor reproduction, apparently due primarily to nest abandonment by breeding birds. We used the model to assess support for the hypothesis that nest abandonment is caused by harassment from biting insects. We obtained indices of blood-feeding insect populations based on the spatially interpolated counts of insects captured in carbon dioxide traps. However, insect trapping was not conducted daily, and so we had incomplete information on a temporally variable covariate of interest. We therefore supplemented our nest survival model with a parallel model for estimating the values of the missing insect covariates. We used Bayesian model selection to identify the best predictors of daily nest survival. Our results suggest that the black fly Simulium annulus may be negatively affecting nest survival of reintroduced whooping cranes, with decreasing nest survival as abundance of S. annulus increases. The modeling framework we have developed will be applied in the future to a larger data set to evaluate the biting-insect hypothesis and other hypotheses for nesting failure in this reintroduced population; resulting inferences will support ongoing efforts to manage this population via an adaptive management approach. Wider application of our approach offers promise for modeling the effects of other temporally varying, but imperfectly observed covariates on nest survival, including the possibility of modeling temporally varying covariates collected from incubating adults. PMID:24340185

A hierarchical nest survival model integrating incomplete temporally varying covariates

USGS Publications Warehouse

Converse, Sarah J.; Royle, J. Andrew; Adler, Peter H.; Urbanek, Richard P.; Barzan, Jeb A.

2013-01-01

Nest success is a critical determinant of the dynamics of avian populations, and nest survival modeling has played a key role in advancing avian ecology and management. Beginning with the development of daily nest survival models, and proceeding through subsequent extensions, the capacity for modeling the effects of hypothesized factors on nest survival has expanded greatly. We extend nest survival models further by introducing an approach to deal with incompletely observed, temporally varying covariates using a hierarchical model. Hierarchical modeling offers a way to separate process and observational components of demographic models to obtain estimates of the parameters of primary interest, and to evaluate structural effects of ecological and management interest. We built a hierarchical model for daily nest survival to analyze nest data from reintroduced whooping cranes (Grus americana) in the Eastern Migratory Population. This reintroduction effort has been beset by poor reproduction, apparently due primarily to nest abandonment by breeding birds. We used the model to assess support for the hypothesis that nest abandonment is caused by harassment from biting insects. We obtained indices of blood-feeding insect populations based on the spatially interpolated counts of insects captured in carbon dioxide traps. However, insect trapping was not conducted daily, and so we had incomplete information on a temporally variable covariate of interest. We therefore supplemented our nest survival model with a parallel model for estimating the values of the missing insect covariates. We used Bayesian model selection to identify the best predictors of daily nest survival. Our results suggest that the black fly Simulium annulus may be negatively affecting nest survival of reintroduced whooping cranes, with decreasing nest survival as abundance of S. annulus increases. The modeling framework we have developed will be applied in the future to a larger data set to evaluate the biting-insect hypothesis and other hypotheses for nesting failure in this reintroduced population; resulting inferences will support ongoing efforts to manage this population via an adaptive management approach. Wider application of our approach offers promise for modeling the effects of other temporally varying, but imperfectly observed covariates on nest survival, including the possibility of modeling temporally varying covariates collected from incubating adults.

Renesting by dusky Canada geese on the Copper River Delta, Alaska

USGS Publications Warehouse

Fondell, Thomas F.; Grand, James B.; Miller, David A.W.; Anthony, R. Michael

2006-01-01

The population of dusky Canada geese (Branta canadensis occidentalis; hereafter duskies) breeding on the Copper River Delta (CRD), Alaska, USA, has been in long-term decline, largely as a result of reduced productivity. Estimates of renesting rates by duskies may be useful for adjusting estimates of the size of the breeding population derived from aerial surveys and for understanding population dynamics. We used a marked population of dusky females to obtain estimates of renesting propensity and renesting interval on the CRD, 1999–2000. Continuation nests, replacement nests initiated without a break in the laying sequence, resulted only after first nests were destroyed in the laying stage with ≤4 eggs laid. Renesting propensity declined with nest age from 72% in mid-laying to 30% in early incubation. Between first nests and renests, mean interval was 11.9 ± 0.6 days, mean distance was 74.5 m (range 0–214 m), and clutch size declined 0.9 ± 0.4 eggs. We incorporated our renesting estimates and available estimates of other nesting parameters into an individual-based model to predict the proportion of first nests, continuation nests, and renests, and to examine female success on the CRD, 1997–2000. Our model predicted that 19–36% of nests each year were continuation nests and renests. Also, through 15 May (the approx. date of breeding ground surveys), 1.1–1.3 nests were initiated per female. Thus, the number of nests per female would have a significant, though relatively consistent, effect on adjusting the relation between numbers of nests found on ground surveys versus numbers of birds seen during aerial surveys. We also suggest a method that managers could use to predict nests per female using nest success of early nests. Our model predicted that relative to observed estimates of nest success, female success was 32–100% greater, due to replacement nests. Thus, although nest success remains low, production for duskies was higher than previously thought. For dusky Canada geese, managers need to consider both continuation nests and renests in designing surveys and in calculating adjustment factors for the expansion of aerial survey data using nest densities.

An integrated analysis of micro- and macro-habitat features as a tool to detect weather-driven constraints: A case study with cavity nesters.

PubMed

Campobello, D; Lindström, J; Di Maggio, R; Sarà, M

2017-01-01

The effects of climate change on animal populations may be shaped by habitat characteristics at both micro- and macro-habitat level, however, empirical studies integrating these two scales of observation are lacking. As analyses of the effects of climate change commonly rely on data from a much larger scale than the microhabitat level organisms are affected at, this mismatch risks hampering progress in developing understanding of the details of the ecological and evolutionary responses of organisms and, ultimately, effective actions to preserve their populations. Cavity nesters, often with a conservation status of concern, are an ideal model because the cavity is a microenvironment potentially different from the macroenvironment but nonetheless inevitably interacting with it. The lesser kestrel (Falco naumanni) is a cavity nester which was until recently classified by as Vulnerable species. Since 2004, for nine years, we collected detailed biotic and abiotic data at both micro- and macro-scales of observation in a kestrel population breeding in the Gela Plain (Italy), a Mediterranean area where high temperatures may reach lethal values for the nest content. We show that macroclimatic features needed to be integrated with both abiotic and biotic factors recorded at a microscale before reliably predicting nest temperatures. Among the nest types used by lesser kestrels, we detected a preferential occupation of the cooler nest types, roof tiles, by early breeders whereas, paradoxically, late breeders nesting with hotter temperatures occupied the overheated nest holes. Not consistent with such a suggested nest selection, the coolest nest type did not host a higher reproductive success than the overheated nests. We discussed our findings in the light of cavity temperatures and nest types deployed within conservation actions assessed by integrating selected factors at different observation scales.

An integrated analysis of micro- and macro-habitat features as a tool to detect weather-driven constraints: A case study with cavity nesters

PubMed Central

Campobello, D.; Lindström, J.; Di Maggio, R.; Sarà, M.

2017-01-01

The effects of climate change on animal populations may be shaped by habitat characteristics at both micro- and macro-habitat level, however, empirical studies integrating these two scales of observation are lacking. As analyses of the effects of climate change commonly rely on data from a much larger scale than the microhabitat level organisms are affected at, this mismatch risks hampering progress in developing understanding of the details of the ecological and evolutionary responses of organisms and, ultimately, effective actions to preserve their populations. Cavity nesters, often with a conservation status of concern, are an ideal model because the cavity is a microenvironment potentially different from the macroenvironment but nonetheless inevitably interacting with it. The lesser kestrel (Falco naumanni) is a cavity nester which was until recently classified by as Vulnerable species. Since 2004, for nine years, we collected detailed biotic and abiotic data at both micro- and macro-scales of observation in a kestrel population breeding in the Gela Plain (Italy), a Mediterranean area where high temperatures may reach lethal values for the nest content. We show that macroclimatic features needed to be integrated with both abiotic and biotic factors recorded at a microscale before reliably predicting nest temperatures. Among the nest types used by lesser kestrels, we detected a preferential occupation of the cooler nest types, roof tiles, by early breeders whereas, paradoxically, late breeders nesting with hotter temperatures occupied the overheated nest holes. Not consistent with such a suggested nest selection, the coolest nest type did not host a higher reproductive success than the overheated nests. We discussed our findings in the light of cavity temperatures and nest types deployed within conservation actions assessed by integrating selected factors at different observation scales. PMID:28319183

Effects of grazing on nesting by upland sandpipers in southcentral North Dakota

USGS Publications Warehouse

Bowen, Bonnie S.; Kruse, Arnold D.

1993-01-01

Grazing by livestock is often used to reduce litter, improve plant vigor, and alter plant species composition, but additional information is needed on the effects of these management practices on upland-nesting birds. Thus, we conducted an experimental study of the effect of grazing on nest density and nest success of upland sandpipers (Bartramia longicauda) in southcentral North Dakota from 1981 to 1987. Our experimental design consisted of 4 treatments and 1 control, each applied to 1 field in each of 3 study areas. The treatments represented options available to grassland managers: spring grazing, autumn grazing, autumn-and-spring grazing, season-long grazing, and control (ungrazed during the study). Nests (n = 342) were found by searching study areas with a cable-chain drag. Nest density was lower (P = 0.006) for treatments where cattle were present (spring, autumn-and-spring, and season-long) than where cattle were not present (autumn and control) during the nesting season. We concluded that grazing during the nesting season reduced the nest density of upland sandpipers. Nest success varied among years (P = 0.01) and was low in the first year of grazing and higher at the end of the study period. We found little evidence that the grazing treatment influenced nest success. We recommend that public lands with breeding populations of upland sandpipers include a complex of fields under various management practices, including fields undisturbed during the nesting season.

Evolution of nesting height in an endangered Hawaiian forest bird in response to a non-native predator.

PubMed

Vanderwerf, Eric A

2012-10-01

The majority of bird extinctions since 1800 have occurred on islands, and non-native predators have been the greatest threat to the persistence of island birds. Island endemic species often lack life-history traits and behaviors that reduce the probability of predation and they can become evolutionarily trapped if they are unable to adapt, but few studies have examined the ability of island species to respond to novel predators. The greatest threat to the persistence of the Oahu Elepaio (Chasiempis ibidis), an endangered Hawaiian forest bird, is nest predation by non-native black rats (Rattus rattus). I examined whether Oahu Elepaio nest placement has changed at the individual and population levels in response to rat predation by measuring nest height and determining whether each nest produced offspring from 1996 to 2011. Average height of Oahu Elepaio nests increased 50% over this 16-year period, from 7.9 m (SE 1.7) to 12.0 m (SE 1.1). There was no net change in height of sequential nests made by individual birds, which means individual elepaios have not learned to place nests higher. Nests ≤3 m off the ground produced offspring less often, and the proportion of such nests declined over time, which suggests that nest-building behavior has evolved through natural selection by predation. Nest success increased over time, which may increase the probability of long-term persistence of the species. Rat control may facilitate the evolution of nesting height by slowing the rate of population decline and providing time for this adaptive response to spread through the population. ©2012 Society for Conservation Biology.

A Statewide Nested Case-Control Study of Preterm Birth and Air Pollution by Source and Composition: California, 2001-2008.

PubMed

Laurent, Olivier; Hu, Jianlin; Li, Lianfa; Kleeman, Michael J; Bartell, Scott M; Cockburn, Myles; Escobedo, Loraine; Wu, Jun

2016-09-01

Preterm birth (PTB) has been associated with exposure to air pollution, but it is unclear whether effects might vary among air pollution sources and components. We studied the relationships between PTB and exposure to different components of air pollution, including gases and particulate matter (PM) by size fraction, chemical composition, and sources. Fine and ultrafine PM (respectively, PM2.5 and PM0.1) by source and composition were modeled across California over 2000-2008. Measured PM2.5, nitrogen dioxide, and ozone concentrations were spatially interpolated using empirical Bayesian kriging. Primary traffic emissions at fine scale were modeled using CALINE4 and traffic indices. Data on maternal characteristics, pregnancies, and birth outcomes were obtained from birth certificates. Associations between PTB (n = 442,314) and air pollution exposures defined according to the maternal residence at birth were examined using a nested matched case-control approach. Analyses were adjusted for maternal age, race/ethnicity, education and neighborhood income. Adjusted odds ratios for PTB in association with interquartile range (IQR) increases in average exposure during pregnancy were 1.133 (95% CI: 1.118, 1.148) for total PM2.5, 1.096 (95% CI: 1.085, 1.108) for ozone, and 1.079 (95% CI: 1.065, 1.093) for nitrogen dioxide. For primary PM, the strongest associations per IQR by source were estimated for onroad gasoline (9-11% increase), followed by onroad diesel (6-8%) and commercial meat cooking (4-7%). For PM2.5 composition, the strongest positive associations per IQR were estimated for nitrate, ammonium, and secondary organic aerosols (11-14%), followed by elemental and organic carbon (2-4%). Associations with local traffic emissions were positive only when analyses were restricted to births with residences geocoded at the tax parcel level. In our statewide nested case-control study population, exposures to both primary and secondary pollutants were associated with an increase in PTB. Laurent O, Hu J, Li L, Kleeman MJ, Bartell SM, Cockburn M, Escobedo L, Wu J. 2016. A statewide nested case-control study of preterm birth and air pollution by source and composition: California, 2001-2008. Environ Health Perspect 124:1479-1486; http://dx.doi.org/10.1289/ehp.1510133.

Risk factors for long-bone fractures in children up to 5 years of age: a nested case-control study.

PubMed

Baker, Ruth; Orton, Elizabeth; Tata, Laila J; Kendrick, Denise

2015-05-01

To investigate risk factors for first long-bone fractures in children up to 5 years old in order to provide evidence about which families could benefit from injury prevention interventions. Population-based matched nested case-control study using The Health Improvement Network, a UK primary care research database, 1988-2004. Maternal, household and child risk factors for injury were assessed among 2456 children with long-bone fractures (cases). 23,661 controls were matched to cases on general practice. Adjusted ORs and 95% CIs were estimated using conditional logistic regression. Fractures of long-bones were independently associated with younger maternal age and higher birth order, with children who were the fourth-born in the family, or later, having a threefold greater odds of fracture compared to first-born children (adjusted OR 3.12, 95% CI 2.08 to 4.68). Children over the age of 1 year had a fourfold (13-24 months, adjusted OR 4.09 95% CI 3.51 to 4.76) to fivefold (37+ months, adjusted OR 4.88 95% CI 4.21 to 5.66) increase in the odds of a long-bone fracture compared to children aged 0-12 months. Children in families with a history of maternal alcohol misuse had a raised odds of long-bone fracture (adjusted OR 2.33, 95% CI 1.13 to 4.82) compared to those with no documented history. Risk factors for long-bone fractures in children less than 5 years old included age above 1 year, increasing birth order, younger maternal age and maternal alcohol misuse. These risk factors should be used to prioritise families and communities for injury prevention interventions. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Towards a precise test for malaria diagnosis in the Brazilian Amazon: comparison among field microscopy, a rapid diagnostic test, nested PCR, and a computational expert system based on artificial neural networks

PubMed Central

2010-01-01

Background Accurate malaria diagnosis is mandatory for the treatment and management of severe cases. Moreover, individuals with asymptomatic malaria are not usually screened by health care facilities, which further complicates disease control efforts. The present study compared the performances of a malaria rapid diagnosis test (RDT), the thick blood smear method and nested PCR for the diagnosis of symptomatic malaria in the Brazilian Amazon. In addition, an innovative computational approach was tested for the diagnosis of asymptomatic malaria. Methods The study was divided in two parts. For the first part, passive case detection was performed in 311 individuals with malaria-related symptoms from a recently urbanized community in the Brazilian Amazon. A cross-sectional investigation compared the diagnostic performance of the RDT Optimal-IT, nested PCR and light microscopy. The second part of the study involved active case detection of asymptomatic malaria in 380 individuals from riverine communities in Rondônia, Brazil. The performances of microscopy, nested PCR and an expert computational system based on artificial neural networks (MalDANN) using epidemiological data were compared. Results Nested PCR was shown to be the gold standard for diagnosis of both symptomatic and asymptomatic malaria because it detected the major number of cases and presented the maximum specificity. Surprisingly, the RDT was superior to microscopy in the diagnosis of cases with low parasitaemia. Nevertheless, RDT could not discriminate the Plasmodium species in 12 cases of mixed infections (Plasmodium vivax + Plasmodium falciparum). Moreover, the microscopy presented low performance in the detection of asymptomatic cases (61.25% of correct diagnoses). The MalDANN system using epidemiological data was worse that the light microscopy (56% of correct diagnoses). However, when information regarding plasma levels of interleukin-10 and interferon-gamma were inputted, the MalDANN performance sensibly increased (80% correct diagnoses). Conclusions An RDT for malaria diagnosis may find a promising use in the Brazilian Amazon integrating a rational diagnostic approach. Despite the low performance of the MalDANN test using solely epidemiological data, an approach based on neural networks may be feasible in cases where simpler methods for discriminating individuals below and above threshold cytokine levels are available. PMID:20459613

Towards a precise test for malaria diagnosis in the Brazilian Amazon: comparison among field microscopy, a rapid diagnostic test, nested PCR, and a computational expert system based on artificial neural networks.

PubMed

Andrade, Bruno B; Reis-Filho, Antonio; Barros, Austeclino M; Souza-Neto, Sebastião M; Nogueira, Lucas L; Fukutani, Kiyoshi F; Camargo, Erney P; Camargo, Luís M A; Barral, Aldina; Duarte, Angelo; Barral-Netto, Manoel

2010-05-06

Accurate malaria diagnosis is mandatory for the treatment and management of severe cases. Moreover, individuals with asymptomatic malaria are not usually screened by health care facilities, which further complicates disease control efforts. The present study compared the performances of a malaria rapid diagnosis test (RDT), the thick blood smear method and nested PCR for the diagnosis of symptomatic malaria in the Brazilian Amazon. In addition, an innovative computational approach was tested for the diagnosis of asymptomatic malaria. The study was divided in two parts. For the first part, passive case detection was performed in 311 individuals with malaria-related symptoms from a recently urbanized community in the Brazilian Amazon. A cross-sectional investigation compared the diagnostic performance of the RDT Optimal-IT, nested PCR and light microscopy. The second part of the study involved active case detection of asymptomatic malaria in 380 individuals from riverine communities in Rondônia, Brazil. The performances of microscopy, nested PCR and an expert computational system based on artificial neural networks (MalDANN) using epidemiological data were compared. Nested PCR was shown to be the gold standard for diagnosis of both symptomatic and asymptomatic malaria because it detected the major number of cases and presented the maximum specificity. Surprisingly, the RDT was superior to microscopy in the diagnosis of cases with low parasitaemia. Nevertheless, RDT could not discriminate the Plasmodium species in 12 cases of mixed infections (Plasmodium vivax + Plasmodium falciparum). Moreover, the microscopy presented low performance in the detection of asymptomatic cases (61.25% of correct diagnoses). The MalDANN system using epidemiological data was worse that the light microscopy (56% of correct diagnoses). However, when information regarding plasma levels of interleukin-10 and interferon-gamma were inputted, the MalDANN performance sensibly increased (80% correct diagnoses). An RDT for malaria diagnosis may find a promising use in the Brazilian Amazon integrating a rational diagnostic approach. Despite the low performance of the MalDANN test using solely epidemiological data, an approach based on neural networks may be feasible in cases where simpler methods for discriminating individuals below and above threshold cytokine levels are available.

Risk of treatment-related esophageal cancer among breast cancer survivors.

PubMed

Morton, L M; Gilbert, E S; Hall, P; Andersson, M; Joensuu, H; Vaalavirta, L; Dores, G M; Stovall, M; Holowaty, E J; Lynch, C F; Curtis, R E; Smith, S A; Kleinerman, R A; Kaijser, M; Storm, H H; Pukkala, E; Weathers, R E; Linet, M S; Rajaraman, P; Fraumeni, J F; Brown, L M; van Leeuwen, F E; Fossa, S D; Johannesen, T B; Langmark, F; Lamart, S; Travis, L B; Aleman, B M P

2012-12-01

Radiotherapy for breast cancer may expose the esophagus to ionizing radiation, but no study has evaluated esophageal cancer risk after breast cancer associated with radiation dose or systemic therapy use. Nested case-control study of esophageal cancer among 289 748 ≥5-year survivors of female breast cancer from five population-based cancer registries (252 cases, 488 individually matched controls), with individualized radiation dosimetry and information abstracted from medical records. The largest contributors to esophageal radiation exposure were supraclavicular and internal mammary chain treatments. Esophageal cancer risk increased with increasing radiation dose to the esophageal tumor location (P(trend )< 0.001), with doses of ≥35 Gy associated with an odds ratio (OR) of 8.3 [95% confidence interval (CI) 2.7-28]. Patients with hormonal therapy ≤5 years preceding esophageal cancer diagnosis had lower risk (OR = 0.4, 95% CI 0.2-0.8). Based on few cases, alkylating agent chemotherapy did not appear to affect risk. Our data were consistent with a multiplicative effect of radiation and other esophageal cancer risk factors (e.g. smoking). Esophageal cancer is a radiation dose-related complication of radiotherapy for breast cancer, but absolute risk is low. At higher esophageal doses, the risk warrants consideration in radiotherapy risk assessment and long-term follow-up.

Effect of biologically active plants used as netst material and the derived benefit to starling nestlings.

PubMed

Clark, Larry; Russell Mason, J

1988-11-01

The European starling Sturnus vulgaris preferentially incorporates fresh sprigs of particular plant species for use as nesting material. Chemicals found in these plants may act to reduce pathogen and ectoparasite populations normally found in nest environments. The present experiments were performed to test this Nest Protection Hypothesis. In the fild, we experimentally determined that wild carrot Daucus carota, a plant species preferred as nest material, effectively reduced the number of hematophagous mites found within nests relative to control nests without green vegetation. Chicks from nests containing wild carrot had higher levels of blood hemoglobin than chicks from control nests. However, there were no differences in weight or feather development. In the laboratory, we found that wild carrot and fleabane, Erigeron philadelphicus, (also preferred by starlings as nest material) substantially reduced the emergence of feeding instars of mites, while garlic mustard, Alliaria officinalis, (commonly available but not preferred) had little effect on the emergence of mites. We infer that preferred plant material may act to inhibit feeding or otherwise delay reproduction of mites, thereby reducing risk of anemia to developing nestlings.

Human oral microbiome and prospective risk for pancreatic cancer: a population-based nested case-control study.

PubMed

Fan, Xiaozhou; Alekseyenko, Alexander V; Wu, Jing; Peters, Brandilyn A; Jacobs, Eric J; Gapstur, Susan M; Purdue, Mark P; Abnet, Christian C; Stolzenberg-Solomon, Rachael; Miller, George; Ravel, Jacques; Hayes, Richard B; Ahn, Jiyoung

2018-01-01

A history of periodontal disease and the presence of circulating antibodies to selected oral pathogens have been associated with increased risk of pancreatic cancer; however, direct relationships of oral microbes with pancreatic cancer have not been evaluated in prospective studies. We examine the relationship of oral microbiota with subsequent risk of pancreatic cancer in a large nested case-control study. We selected 361 incident adenocarcinoma of pancreas and 371 matched controls from two prospective cohort studies, the American Cancer Society Cancer Prevention Study II and the National Cancer Institute Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial. From pre-diagnostic oral wash samples, we characterised the composition of the oral microbiota using bacterial 16S ribosomal RNA (16S rRNA) gene sequencing. The associations between oral microbiota and risk of pancreatic cancer, controlling for the random effect of cohorts and other covariates, were examined using traditional and L1-penalised least absolute shrinkage and selection operator logistic regression. Carriage of oral pathogens, Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans , were associated with higher risk of pancreatic cancer (adjusted OR for presence vs absence=1.60 and 95% CI 1.15 to 2.22; OR=2.20 and 95% CI 1.16 to 4.18, respectively). Phylum Fusobacteria and its genus Leptotrichia were associated with decreased pancreatic cancer risk (OR per per cent increase of relative abundance=0.94 and 95% CI 0.89 to 0.99; OR=0.87 and 95% CI 0.79 to 0.95, respectively). Risks related to these phylotypes remained after exclusion of cases that developed within 2 years of sample collection, reducing the likelihood of reverse causation in this prospective study. This study provides supportive evidence that oral microbiota may play a role in the aetiology of pancreatic cancer. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Lack of spatial genetic structure among nesting and wintering King Eiders

USGS Publications Warehouse

Pearce, J.M.; Talbot, S.L.; Pierson, Barbara J.; Petersen, M.R.; Scribner, K.T.; Dickson, D.L.; Mosbech, A.

2004-01-01

The King Eider (Somateria spectabilis) has been delineated into two broadly distributed breeding populations in North America (the western and eastern Arctic) on the basis of banding data and their use of widely separated Pacific and Atlantic wintering areas. Little is known about the level of gene flow between these two populations. Also unknown is whether behavioral patterns common among migratory waterfowl, such as site fidelity to wintering areas and pair formation at these sites, have existed for sufficient time to create a population structure defined by philopatry to wintering rather than to nesting locations. We used six nuclear microsatellite DNA loci and cytochrome b mitochondrial DNA sequence data to estimate the extent of spatial genetic differentiation among nesting and wintering areas of King Eiders across North America and adjacent regions. Estimates of interpopulation variance in microsatellite allele and mtDNA haplotype frequency were both low and nonsignificant based on samples from three wintering and four nesting areas. Results from nested clade analysis, mismatch distributions, and coalescent-based analyses suggest historical population growth and gene flow that collectively may have homogenized gene frequencies. The presence of several unique mtDNA haplotypes among birds wintering near Greenland suggests that gene flow may now be more limited between the western and eastern Arctic, which is consistent with banding data.

Use of combined oral contraceptives and risk of venous thromboembolism: nested case-control studies using the QResearch and CPRD databases

PubMed Central

Coupland, Carol; Hippisley-Cox, Julia

2015-01-01

Objective To investigate the association between use of combined oral contraceptives and risk of venous thromboembolism, taking the type of progestogen into account. Design Two nested case-control studies. Setting General practices in the United Kingdom contributing to the Clinical Practice Research Datalink (CPRD; 618 practices) and QResearch primary care database (722 practices). Participants Women aged 15-49 years with a first diagnosis of venous thromboembolism in 2001-13, each matched with up to five controls by age, practice, and calendar year. Main outcome measures Odds ratios for incident venous thromboembolism and use of combined oral contraceptives in the previous year, adjusted for smoking status, alcohol consumption, ethnic group, body mass index, comorbidities, and other contraceptive drugs. Results were combined across the two datasets. Results 5062 cases of venous thromboembolism from CPRD and 5500 from QResearch were analysed. Current exposure to any combined oral contraceptive was associated with an increased risk of venous thromboembolism (adjusted odds ratio 2.97, 95% confidence interval 2.78 to 3.17) compared with no exposure in the previous year. Corresponding risks associated with current exposure to desogestrel (4.28, 3.66 to 5.01), gestodene (3.64, 3.00 to 4.43), drospirenone (4.12, 3.43 to 4.96), and cyproterone (4.27, 3.57 to 5.11) were significantly higher than those for second generation contraceptives levonorgestrel (2.38, 2.18 to 2.59) and norethisterone (2.56, 2.15 to 3.06), and for norgestimate (2.53, 2.17 to 2.96). The number of extra cases of venous thromboembolism per year per 10 000 treated women was lowest for levonorgestrel (6, 95% confidence interval 5 to 7) and norgestimate (6, 5 to 8), and highest for desogestrel (14, 11 to 17) and cyproterone (14, 11 to 17). Conclusions In these population based, case-control studies using two large primary care databases, risks of venous thromboembolism associated with combined oral contraceptives were, with the exception of norgestimate, higher for newer drug preparations than for second generation drugs. PMID:26013557

Preliminary analysis of Greater Sage-grouse reproduction in the Virginia Mountains of northwestern Nevada

USGS Publications Warehouse

Coates, Peter S.; Lockyer, Zachary B.; Farinha, Melissa A.; Sweeney, Joelle M.; Johnson, Valerie M.; Meshriy, Matthew G.; Espinosa, Shawn P.; Delehanty, David J.; Casazza, Michael L.

2011-01-01

Relationships between habitat selection and population vital rates of greater sage-grouse (Centrocercus urophasianus; hereafter sage-grouse), recently designated as a candidate species under the Endangered Species Act, within the Great Basin are not well-understood. The growing development of renewable energy infrastructure within areas inhabited by sage-grouse is thought to influence predator and vegetation communities. For example, common ravens (Corvus corax), a synanthropic sage-grouse nest predator, are increasing range-wide and select transmission lines and other tall structures for nesting and perching. In the Virginia Mountains of northwestern Nevada, we collected preliminary information of space-use, habitat selection, and population vital rates during the nesting and brood-rearing period over two years on 56 sage-grouse. Additionally, videography at nest sites (n = 22) was used to identify sage-grouse nest predators. The study area is a potential site for renewable energy developments (i.e., wind and solar), and we plan to continue monitoring this population using a before-after-control-impact study design. The results reported here are preliminary and further data are required before conclusions can be drawn from this population of sage-grouse.

Tropical flatback turtle (Natator depressus) embryos are resilient to the heat of climate change.

PubMed

Howard, Robert; Bell, Ian; Pike, David A

2015-10-01

Climate change is threatening reproduction of many ectotherms by increasing nest temperatures, potentially making it more difficult for females to locate nest sites that provide suitable incubation regimes during embryonic development. Elevated nest temperatures could increase the incidence of embryonic mortality and/or maladaptive phenotypes. We investigated whether elevated nest temperatures reduce hatching success in tropical flatback turtles (Natator depressus) nesting in the Gulf of Carpentaria, Australia. Egg incubation treatments began at 29.5°C and progressively increased in temperature throughout incubation, up to maxima of 31, 32, 33, 34 and 35°C. Elevated nest temperatures did not reduce hatching success or hatchling body size relative to control temperatures (29.5°C), but did speed up embryonic development. A combination of sudden exposure to high temperatures during the first 2 weeks of incubation (>36°C for 48 h) and prolonged warming throughout incubation (from 29.5-35°C) did not reduce hatching success. We also recorded an unusually high pivotal sex-determining temperature in this flatback turtle population relative to other sea turtle populations: an equal ratio of male and female hatchlings is produced at ∼30.4°C. This adaptation may allow some flatback turtle populations to continue producing large numbers of hatchlings of both sexes under the most extreme climate change scenarios. Some tropical populations of nesting flatbacks may possess important adaptations to high-temperature incubation environments, which are not found in more southerly temperate populations. © 2015. Published by The Company of Biologists Ltd.

Comprehensive Comparison between Empty Nest and Non-Empty Nest Elderly: A Cross-Sectional Study among Rural Populations in Northeast China

PubMed Central

Chang, Ye; Guo, Xiaofan; Guo, Liang; Li, Zhao; Yang, Hongmei; Yu, Shasha; Sun, Guozhe; Sun, Yingxian

2016-01-01

This study aimed to comprehensively compare the general characteristics, lifestyles, serum parameters, ultrasonic cardiogram (UCG) parameters, depression, quality of life, and various comorbidities between empty nest and non-empty nest elderly among rural populations in northeast China. This analysis was based on our previous study which was conducted from January 2012 to August 2013, using a multistage, stratified, random cluster sampling scheme. The final analyzed sample consisted of 3208 participants aged no less than 60 years, which was further classified into three groups: non-empty nest group, empty nest group (living as a couple), and empty nest group (living alone). More than half of the participants were empty nest elderly (60.5%). There were no significant statistical differences for serum parameters, UCG parameters, lifestyles, dietary pattern, and scores of Patient Health Questionnaire-9 (PHQ-9) and World Health Organization Quality of Life questionnaire, abbreviated version (WHOQOL-BREF) among the three groups. Empty nest elderly showed no more risk for comorbidities such as general obesity, abdominal obesity, hyperuricemia, hyperhomocysteinemia, diabetes, dyslipidemia, left atrial enlargement (LAE), and stroke. Our study indicated that empty nest elderly showed no more risk for depression, low quality of life and comorbidities such as general obesity, abdominal obesity, hyperuricemia, hyperhomocysteinemia, diabetes, dyslipidemia, LAE, and stroke among rural populations in northeast China. PMID:27618905

Comprehensive Comparison between Empty Nest and Non-Empty Nest Elderly: A Cross-Sectional Study among Rural Populations in Northeast China.

PubMed

Chang, Ye; Guo, Xiaofan; Guo, Liang; Li, Zhao; Yang, Hongmei; Yu, Shasha; Sun, Guozhe; Sun, Yingxian

2016-08-27

This study aimed to comprehensively compare the general characteristics, lifestyles, serum parameters, ultrasonic cardiogram (UCG) parameters, depression, quality of life, and various comorbidities between empty nest and non-empty nest elderly among rural populations in northeast China. This analysis was based on our previous study which was conducted from January 2012 to August 2013, using a multistage, stratified, random cluster sampling scheme. The final analyzed sample consisted of 3208 participants aged no less than 60 years, which was further classified into three groups: non-empty nest group, empty nest group (living as a couple), and empty nest group (living alone). More than half of the participants were empty nest elderly (60.5%). There were no significant statistical differences for serum parameters, UCG parameters, lifestyles, dietary pattern, and scores of Patient Health Questionnaire-9 (PHQ-9) and World Health Organization Quality of Life questionnaire, abbreviated version (WHOQOL-BREF) among the three groups. Empty nest elderly showed no more risk for comorbidities such as general obesity, abdominal obesity, hyperuricemia, hyperhomocysteinemia, diabetes, dyslipidemia, left atrial enlargement (LAE), and stroke. Our study indicated that empty nest elderly showed no more risk for depression, low quality of life and comorbidities such as general obesity, abdominal obesity, hyperuricemia, hyperhomocysteinemia, diabetes, dyslipidemia, LAE, and stroke among rural populations in northeast China.

A case-control comparison of direct healthcare-provider medical costs of chronic idiopathic constipation and irritable bowel syndrome with constipation in a community-based cohort

PubMed Central

Herrick, Linda M.; Spalding, William M.; Saito, Yuri A.; Moriarty, James; Schleck, Cathy

2017-01-01

Objective Patients with constipation account for 3.1 million United States physician visits a year, but care costs for patients with irritable bowel syndrome with constipation (IBS-C) or chronic idiopathic constipation (CIC) compared to the general public have received little study. The study aim was to describe healthcare utilization and compare medical costs for patients with IBS-C or CIC versus matched controls from a community-based sample. Methods A nested case-control sample (IBS-C and CIC cases) and matched controls (1:2) for each case group were selected from Olmsted County, MN individuals responding to a community-based survey of gastrointestinal symptoms (2008) who received healthcare from a participating Rochester Epidemiology Project (REP) provider. Using REP healthcare utilization data, unadjusted and adjusted standardized costs were compared for the 2- and 10-year periods prior to the survey for 115 IBS-C patients and 230 controls and 365 CIC patients and 730 controls. Two time periods were chosen as these conditions are episodic but long-term. Results Outpatient costs for IBS-C ($6,800) and CIC ($6,284) patients over a 2-year period prior to the survey were significantly higher than controls ($4,242 and $5,254 respectively) after adjusting for co-morbidities, age, and sex. IBS-C outpatient costs ($25,448) and emergency room costs ($6,892) were significantly higher than controls ($21,024 and $3,962 respectively) for the 10-year period prior. Unadjusted data analyses of cases compared to controls demonstrated significantly higher imaging costs for IBS-C cases and procedure costs for CIC cases over the 10-year period. Limitations Data were collected from a random community sample primarily receiving care from a limited number of providers in that area. Conclusions Patients with IBS-C and CIC had significantly higher outpatient costs for the 2-year period compared with controls. IBS-C patients also had higher ER costs than the general population. PMID:27783533

A population-based study of the drug interaction between proton pump inhibitors and clopidogrel

PubMed Central

Juurlink, David N.; Gomes, Tara; Ko, Dennis T.; Szmitko, Paul E.; Austin, Peter C.; Tu, Jack V.; Henry, David A.; Kopp, Alex; Mamdani, Muhammad M.

2009-01-01

Background Most proton pump inhibitors inhibit the bioactivation of clopidogrel to its active metabolite. The clinical significance of this drug interaction is unknown. Methods We conducted a population-based nested case–control study among patients aged 66 years or older who commenced clopidogrel between Apr. 1, 2002, and Dec. 31, 2007, following hospital discharge after treatment of acute myocardial infarction. The cases in our study were those readmitted with acute myocardial infarction within 90 days after discharge. We performed a secondary analysis considering events within 1 year. Event-free controls (at a ratio of 3:1) were matched to cases on age, percutaneous coronary intervention and a validated risk score. We categorized exposure to proton pump inhibitors before the index date as current (within 30 days), previous (31–90 days) or remote (91–180 days). Results Among 13 636 patients prescribed clopidogrel following acute myocardial infarction, we identified 734 cases readmitted with myocardial infarction and 2057 controls. After extensive multivariable adjustment, current use of proton pump inhibitors was associated with an increased risk of reinfarction (adjusted odds ratio [OR] 1.27, 95% confidence interval [CI] 1.03–1.57). We found no association with more distant exposure to proton pump inhibitors or in multiple sensitivity analyses. In a stratified analysis, pantoprazole, which does not inhibit cytochrome P450 2C19, had no association with readmission for myocardial infarction (adjusted OR 1.02, 95% CI 0.70–1.47). Interpretation Among patients receiving clopidogrel following acute myocardial infarction, concomitant therapy with proton pump inhibitors other than pantoprazole was associated with a loss of the beneficial effects of clopidogrel and an increased risk of reinfarction. PMID:19176635

Proton pump inhibitor and histamine-2 receptor antagonist use and risk of liver cancer in two population-based studies.

PubMed

Tran, K T; McMenamin, Ú C; Hicks, B; Murchie, P; Thrift, A P; Coleman, H G; Iversen, L; Johnston, B T; Lee, A J; Cardwell, C R

2018-05-09

Proton pump inhibitors (PPIs) and histamine-2 receptor antagonists (H2RAs) are commonly used. PPIs have been shown to promote liver cancer in rats; however, only one study has examined the association in humans. To investigate PPIs and H2RAs and risk of primary liver cancer in two large independent study populations. We conducted a nested case-control study within the Primary Care Clinical Informatics Unit (PCCIU) database in which up to five controls were matched to cases with primary liver cancer, recorded by General Practitioners. Odds ratios (ORs) and 95% confidence intervals (95% CIs) for associations with prescribed PPIs and H2RAs were calculated using conditional logistic regression. We also conducted a prospective cohort study within the UK Biobank using self-reported medication use and cancer-registry recorded primary liver cancer. Hazard ratios (HRs) and 95% CIs were calculated using Cox regression. In the PCCIU case-control analysis, 434 liver cancer cases were matched to 2103 controls. In the UK Biobank cohort, 182 of 475 768 participants developed liver cancer. In both, ever use of PPIs was associated with increased liver cancer risk (adjusted OR 1.80, 95% CI 1.34, 2.41 and adjusted HR 1.99, 95% CI 1.34, 2.94 respectively). There was little evidence of association with H2RA use (adjusted OR 1.21, 95% CI 0.84, 1.76 and adjusted HR 1.70, 95% CI 0.82, 3.53 respectively). We found some evidence that PPI use was associated with liver cancer. Whether this association is causal or reflects residual confounding or reverse causation requires additional research. © 2018 John Wiley & Sons Ltd.

Estimating population size of Pygoscelid Penguins from TM data

NASA Technical Reports Server (NTRS)

Olson, Charles E., Jr.; Schwaller, Mathew R.; Dahmer, Paul A.

1987-01-01

An estimate was made toward a continent wide population of penguins. The results indicate that Thematic Mapper data can be used to identify penguin rookeries due to the unique reflectance properties of guano. Strong correlations exist between nesting populations and rookery area occupied by the birds. These correlations allow estimation of the number of nesting pairs in colonies. The success of remote sensing and biometric analyses leads one to believe that a continent wide estimate of penguin populations is possible based on a timely sample employing ground based and remote sensing techniques. Satellite remote sensing along the coastline may well locate previously undiscovered penguin nesting sites, or locate rookeries which have been assumed to exist for over a half century, but never located. Observations which found that penguins are one of the most sensitive elements in the complex of Southern Ocean ecosystems motivated this study.

Nested case–control study of the effects of non-steroidal anti-inflammatory drugs on breast cancer risk and stage

PubMed Central

Sharpe, C R; Collet, J-P; McNutt, M; Belzile, E; Boivin, J-F; Hanley, J A

2000-01-01

We carried out a nested case–control study to measure the rate ratio (RR) for invasive female breast cancer in relation to non-steroidal anti-inflammatory drug (NSAID) use. The source population consisted of the female beneficiaries of the Saskatchewan Prescription Drug Plan from 1981 to 1995 with no history of cancer since 1970. Four controls/case, matched on age and sampling time, were randomly selected. Dispensing rates during successive time periods characterized NSAID exposure. RRs associated with exposure during each period were adjusted for exposure during the others. Confounding by other determinants was studied in analyses adjusted with data obtained by interviewing samples of subjects accrued from mid-1991 to mid-1995. We accrued 5882 cases and 23 517 controls. Increasing NSAID exposure 2–5 years preceding diagnosis was associated with a trend towards a decreasing RR (P -trend = 0.003); for the highest exposure level RR = 0.76, 95% confidence interval 0.63–0.92. This protective effect could not be attributed to confounding by other determinants. In analyses involving only the cases, NSAID exposure 2–5 and 6–10 years preceding diagnosis was associated with significantly reduced risks of presenting with a large tumour (> 5 cm diameter) or distant metastasis, but not regional lymph node metastasis. The use of NSAIDs may retard the growth of breast cancers and prevent distant metastasis. © 2000 Cancer Research Campaign PMID:10883678

Applications of a simulation model to decisions in mallard management

USGS Publications Warehouse

Cowardin, L.M.; Johnson, D.H.; Shaffer, T.L.; Sparling, D.W.

1988-01-01

A system comprising simulation models and data bases for habitat availability and nest success rates was used to predict results from a mallard (Anas platyrhynchos) management plan and to compare six management methods with a control. Individual treatments in the applications included land purchase for waterfowl production, wetland easement purchase, lease of uplands for waterfowl management, cropland retirement, use of no-till winter wheat, delayed cutting of alfalfa, installation of nest baskets, nesting island construction, and use of predator-resistant fencing.The simulations predicted that implementation of the management plan would increase recruits by 24%. Nest baskets were the most effective treatment, accounting for 20.4% of the recruits. No-till winter wheat was the second most effective, accounting for 5.9% of the recruits. Wetland loss due to drainage would cause an 11% loss of breeding population in 10 years.The models were modified to account for migrational homing. The modification indicated that migrational homing would enhance the effects of management. Nest success rates were critical contributions to individual management methods. The most effective treatments, such as nest baskets, had high success rates and affected a large portion of the breeding population.Economic analyses indicated that nest baskets would be the most economical of the three techniques tested. The applications indicated that the system is a useful tool to aid management decisions, but data are scarce for several important variables. Basic research will be required to adequately model the effect of migrational homing and density dependence on production. The comprehensive nature of predictions desired by managers will also require that production models like the one described here be extended to encompass the entire annual cycle of waterfowl.

Managing American Oystercatcher (Haematopus palliatus) population qrowth by targeting nesting season vital rates

USGS Publications Warehouse

Felton, Shilo K.; Hostetter, Nathan J.; Pollock, Kenneth H.; Simons, Theodore R.

2017-01-01

In populations of long-lived species, adult survival typically has a relatively high influence on population growth. From a management perspective, however, adult survival can be difficult to increase in some instances, so other component rates must be considered to reverse population declines. In North Carolina, USA, management to conserve the American Oystercatcher (Haematopus palliatus) targets component vital rates related to fecundity, specifically nest and chick survival. The effectiveness of such a management approach in North Carolina was assessed by creating a three-stage female-based deterministic matrix model. Isoclines were produced from the matrix model to evaluate minimum nest and chick survival rates necessary to reverse population decline, assuming all other vital rates remained stable at mean values. Assuming accurate vital rates, breeding populations within North Carolina appear to be declining. To reverse this decline, combined nest and chick survival would need to increase from 0.14 to ≤ 0.27, a rate that appears to be attainable based on historical estimates. Results are heavily dependent on assumptions of other vital rates, most notably adult survival, revealing the need for accurate estimates of all vital rates to inform management actions. This approach provides valuable insights for evaluating conservation goals for species of concern.

Occupational solvent exposure and adult chronic lymphocytic leukemia: No risk in a population-based case-control study in four Nordic countries.

PubMed

Talibov, Madar; Auvinen, Anssi; Weiderpass, Elisabete; Hansen, Johnni; Martinsen, Jan-Ivar; Kjaerheim, Kristina; Tryggvadottir, Laufey; Pukkala, Eero

2017-09-15

The aim of this study was to assess the effect of occupational solvent exposure on the risk of adult chronic lymphocytic leukemia (CLL). The current case-control study was nested in the Nordic Occupational Cancer Study (NOCCA) cohort. 20,615 CLL cases diagnosed in 1961-2005 in Finland, Iceland, Norway, and Sweden, and 103,075 population-based controls matched by year of birth, sex, and country were included. Occupational histories for cases and controls were obtained from census records in 1960, 1970, 1980/1981, and 1990. Exposure to selected solvents was estimated by using the NOCCA job-exposure matrix (NOCCA-JEM). Odds ratios (OR) and 95% confidence intervals (95% CI) were estimated by using conditional logistic regression models. Overall, nonsignificant CLL risk elevations were observed for methylene chloride, perchloroethylene, and 1,1,1-trichloroethane. Compared to unexposed, significantly increased risks were observed for cumulative perchloroethylene exposure ≤13.3 ppm-years (OR = 1.85, 95% CI 1.16-2.96) and average life-time perchloroethylene exposure ≤2.5 ppm (1.61, 95% CI 1.01-2.56) among women, and cumulative methylene chloride exposure ≤12.5 ppm-years (OR = 1.19, 95% CI 1.01-1.41) and 12.5-74.8 ppm-years (OR = 1.23, 95% CI 1.01-1.51) among men in an analysis with 5 years lag-time, though without dose-response pattern. Decreased CLL risk was observed for aliphatic and alicyclic hydrocarbon solvents and toluene. This study did not support associations for solvent exposure and CLL. Observed weak associations for methylene chloride, perchloroethylene, 1,1,1-trichloroethane exposures, aliphatic and alicyclic hydrocarbons and toluene were not consistent across sexes, and showed no gradient with amount of exposure. © 2017 UICC.

Nest survival of piping plovers at a dynamic reservoir indicates an ecological trap for a threatened population

USGS Publications Warehouse

Anteau, Michael J.; Shaffer, Terry L.; Sherfy, Mark H.; Sovada, Marsha A.; Stucker, Jennifer H.; Wiltermuth, Mark T.

2012-01-01

In the past 60 years, reservoirs have reshaped riverine ecosystems and transformed breeding habitats used by the threatened piping plover (Charadrius melodus; hereafter plover). Currently, 29% of the Northern Great Plains plover population nests at reservoirs that might function as ecological traps because reservoirs have more diverse habitat features and greater dynamics in water levels than habitats historically used by breeding plovers. We examined factors influencing daily survival rates (DSR) of 346 plover nests at Lake Sakakawea (SAK; reservoir) during 2006–2009 by evaluating multiple a priori models, and we used our best model to hindcast nest success of plovers during 1985–2009. Our observed and hindcast estimates of nest success were low compared to published estimates. Previous findings indicate that plovers prefer nest sites that are low relative to water level. We found that elevation of nests above the water level had a strong positive correlation with DSR because water levels of SAK typically increased throughout the nesting period. Habitat characteristics on the reservoir differ from those that shaped nest-site selection for plovers. Accordingly, extraordinary nest loss occurs there in many years, largely due to inundation of nests, and based on low fledging rates those losses were not compensated by potential changes in chick survival. Therefore, our example supports the concept of ecological traps in birds because it addresses quantitative assessments of habitat preference and productivity over 25 years (since species listing) and affects a large portion of the population.

Fumonisin B1 and Risk of Hepatocellular Carcinoma in Two Chinese Cohorts

PubMed Central

Persson, E. Christina; Sewram, Vikash; Evans, Alison A.; London, W. Thomas; Volkwyn, Yvette; Shen, Yen-Ju; Van Zyl, Jacobus A.; Chen, Gang; Lin, Wenyao; Shephard, Gordon S.; Taylor, Philip R.; Fan, Jin-Hu; Dawsey, Sanford M.; Qiao, You-Lin; McGlynn, Katherine A.; Abnet, Christian C.

2011-01-01

Fumonisin B1 (FB1), a mycotoxin that contaminates corn in certain climates, has been demonstrated to cause hepatocellular cancer (HCC) in animal models. Whether a relationship between FB1 and HCC exists in humans is not known. To examine the hypothesis, we conducted case-control studies nested within two large cohorts in China; the Haimen City Cohort and the General Population Study of the Nutritional Intervention Trials cohort in Linxian. In the Haimen City Cohort, nail FB1 levels were determined in 271 HCC cases and 280 controls. In the General Population Nutritional Intervention Trial, nail FB1 levels were determined in 72 HCC cases and 147 controls. In each population, odds ratios and 95% confidence intervals (95%CI) from logistic regression models estimated the association between measurable FB1 and HCC, adjusting for hepatitis B virus infection and other factors. A meta-analysis that included both populations was also conducted. The analysis revealed no statistically significant association between FB1 and HCC in either Haimen City (OR=1.10, 95%CI=0.64–1.89) or in Linxian (OR=1.47, 95%CI=0.70–3.07). Similarly, the pooled meta-analysis showed no statistically significant association between FB1 exposure and HCC (OR=1.22, 95%CI=0.79–1.89). These findings, although somewhat preliminary, do not support an associated between FB1 and HCC. PMID:22142693

Head or brain injuries and Alzheimer's disease: A nested case-control register study.

PubMed

Tolppanen, Anna-Maija; Taipale, Heidi; Hartikainen, Sirpa

2017-12-01

Many previous studies have been limited by self- or proxy-reported injury or short follow-up. We investigated whether head or brain injuries are associated with Alzheimer's disease (AD), possible modifying factors and dose-response relationship. Nested register-based case-control study of all community dwellers who received clinically verified AD diagnosis in Finland in 2005 to 2011 (n = 70,719) and one to four matched controls for each case (n of controls = 282,862). The magnitude of association between hospital-treated head and/or brain injuries was strongly dependent on the lag time between exposure and outcome. With a 5-year lag time, head injury (adjusted odds ratio; 95% confidence interval 1.19; 1.15-1.23) or brain injury (1.23; 1.18-1.29) was associated with higher risk of AD. Dose-response relationship with number and severity of injuries was observed. Associations were stronger in those with earlier onset of AD. Stronger associations with shorter lag times indicate that head and/or brain injuries may also reflect the ongoing AD disease process. Copyright © 2017 the Alzheimer's Association. Published by Elsevier Inc. All rights reserved.

Mumps disease outbreak in Davangere district of Karnataka, India.

PubMed

Raut, C G; Sinha, D P; Jayaprakash, H; Hanumiah, H; Manjunatha, M J

2015-01-01

Mumps is a vaccine-preventable disease that usually occurs as a parotitis, but it can also lead to several life- threatening complications, including pancreatitis, meningitis and encephalitis. To determine and diagnosis of mumps disease, which is communicable disease usually affects childrens. Although it is seen worldwide, but outbreaks not common in India. Thirty one suspected mumps cases, who presented to the unimmunized population of Chikkahallivana village in Davangere district of Karnataka, India in January 2014, with clinical evidence of fever, cervical lymphadenitis and ear pain, manifest with self-limited uni-or bilateral parotitis. A total of 31 cases consisting of 31 blood and 31 throat swabs were tested for diagnosis of mumps disease. Of the 31 suspected cases, laboratory results showed 18 positive for mumps IgM antibodies and 7 cases showed presence of mumps virus RNA by RT-PCR using MV specific nested primers. From 31 cases, 5 were positive with both the methods. We confirmed the cases by serological as well as a sensitive RT-nested PCR-based method and sequencing results for the molecular identification of mumps infection. Sequencing results of the SH gene identified outbreak strain as genotype C, which was consistent with other outbreaks in India.

Vascular factors in suspected normal pressure hydrocephalus

PubMed Central

Agerskov, Simon; Rabiei, Katrin; Marlow, Thomas; Jensen, Christer; Guo, Xinxin; Kern, Silke; Wikkelsø, Carsten; Skoog, Ingmar

2016-01-01

Objective: We examined clinical and imaging findings of suspected idiopathic normal pressure hydrocephalus (iNPH) in relation to vascular risk factors and white matter lesions (WMLs), using a nested case-control design in a representative, population-based sample. Methods: From a population-based sample, 1,235 persons aged 70 years or older were examined with CT of the brain between 1986 and 2000. We identified 55 persons with hydrocephalic ventricular enlargement, i.e., radiologic findings consistent with iNPH. Among these, 26 had clinical signs that fulfilled international guideline criteria for probable iNPH. These cases were labeled suspected iNPH. Each case was matched to 5 controls from the same sample, based on age, sex, and study cohort. Data on risk factors were obtained from clinical examinations and the Swedish Hospital Discharge Register. History of hypertension, diabetes mellitus (DM), smoking, overweight, history of coronary artery disease, stroke/TIA, and WMLs on CT were examined. Risk factors associated with iNPH with a p value <0.1 in χ2 tests were included in conditional logistic regression models. Results: In the regression analyses, suspected iNPH was related to moderate to severe WMLs (odds ratio [OR] 5.2; 95% confidence interval [CI]: 1.5–17.6), while hydrocephalic ventricular enlargement was related to hypertension (OR 2.7; 95% CI: 1.1–6.8), moderate to severe WMLs (OR 6.5; 95% CI: 2.1–20.3), and DM (OR 4.3; 95% CI: 1.1–16.3). Conclusions: Hypertension, WMLs, and DM were related to clinical and imaging features of iNPH, suggesting that vascular mechanisms are involved in the pathophysiology. These findings might have implications for understanding disease mechanisms in iNPH and possibly prevention. PMID:26773072

Circulating FABP4 is a prognostic biomarker in patients with acute coronary syndrome but not in asymptomatic individuals.

PubMed

Reiser, Hans; Klingenberg, Roland; Hof, Danielle; Cooksley-Decasper, Seraina; Fuchs, Nina; Akhmedov, Alexander; Zoller, Stefan; Marques-Vidal, Pedro; Marti Soler, Helena; Heg, Dik; Landmesser, Ulf; Rodondi, Nicolas; Mach, Francois; Windecker, Stephan; Vollenweider, Peter; Matter, Christian M; Lüscher, Thomas F; von Eckardstein, Arnold; Gawinecka, Joanna

2015-08-01

Blood-borne biomarkers reflecting atherosclerotic plaque burden have great potential to improve clinical management of atherosclerotic coronary artery disease and acute coronary syndrome (ACS). Using data integration from gene expression profiling of coronary thrombi versus peripheral blood mononuclear cells and proteomic analysis of atherosclerotic plaque-derived secretomes versus healthy tissue secretomes, we identified fatty acid-binding protein 4 (FABP4) as a biomarker candidate for coronary artery disease. Its diagnostic and prognostic performance was validated in 3 different clinical settings: (1) in a cross-sectional cohort of patients with stable coronary artery disease, ACS, and healthy individuals (n=820), (2) in a nested case-control cohort of patients with ACS with 30-day follow-up (n=200), and (3) in a population-based nested case-control cohort of asymptomatic individuals with 5-year follow-up (n=414). Circulating FABP4 was marginally higher in patients with ST-segment-elevation myocardial infarction (24.9 ng/mL) compared with controls (23.4 ng/mL; P=0.01). However, elevated FABP4 was associated with adverse secondary cerebrovascular or cardiovascular events during 30-day follow-up after index ACS, independent of age, sex, renal function, and body mass index (odds ratio, 1.7; 95% confidence interval, 1.1-2.5; P=0.02). Circulating FABP4 predicted adverse events with similar prognostic performance as the GRACE in-hospital risk score or N-terminal pro-brain natriuretic peptide. Finally, no significant difference between baseline FABP4 was found in asymptomatic individuals with or without coronary events during 5-year follow-up. Circulating FABP4 may prove useful as a prognostic biomarker in risk stratification of patients with ACS. © 2015 American Heart Association, Inc.

Threshold Dynamics of a Temperature-Dependent Stage-Structured Mosquito Population Model with Nested Delays.

PubMed

Wang, Xiunan; Zou, Xingfu

2018-05-21

Mosquito-borne diseases remain a significant threat to public health and economics. Since mosquitoes are quite sensitive to temperature, global warming may not only worsen the disease transmission case in current endemic areas but also facilitate mosquito population together with pathogens to establish in new regions. Therefore, understanding mosquito population dynamics under the impact of temperature is considerably important for making disease control policies. In this paper, we develop a stage-structured mosquito population model in the environment of a temperature-controlled experiment. The model turns out to be a system of periodic delay differential equations with periodic delays. We show that the basic reproduction number is a threshold parameter which determines whether the mosquito population goes to extinction or remains persistent. We then estimate the parameter values for Aedes aegypti, the mosquito that transmits dengue virus. We verify the analytic result by numerical simulations with the temperature data of Colombo, Sri Lanka where a dengue outbreak occurred in 2017.

Population dynamics of long-tailed ducks breeding on the Yukon-Kuskokwim Delta, Alaska

USGS Publications Warehouse

Schamber, Jason L.; Flint, Paul L.; Grand, J. Barry; Wilson, Heather M.; Morse, Julie A.

2009-01-01

Population estimates for long-tailed ducks in North America have declined by nearly 50% over the past 30 years. Life history and population dynamics of this species are difficult to ascertain, because the birds nest at low densities across a broad range of habitat types. Between 1991 and 2004, we collected information on productivity and survival of long-tailed ducks at three locations on the Yukon-Kuskokwim Delta. Clutch size averaged 7.1 eggs, and nesting success averaged 30%. Duckling survival to 30 days old averaged 10% but was highly variable among years, ranging from 0% to 25%. Apparent annual survival of adult females based on mark-recapture of nesting females was estimated at 74%. We combined these estimates of survival and productivity into a matrix-based population model, which predicted an annual population decline of 19%. Elasticities indicated that population growth rate (λ) was most sensitive to changes in adult female survival. Further, the relatively high sensitivity of λ to duckling survival suggests that low duckling survival may be a bottleneck to productivity in some years. These data represent the first attempt to synthesize a population model for this species. Although our analyses were hampered by the small sample sizes inherent in studying a dispersed nesting species, our model provides a basis for management actions and can be enhanced as additional data become available.

Lysophosphatidic Acid and Apolipoprotein A1 Predict Increased Risk of Developing World Trade Center Lung Injury: A Nested Case-Control Study

PubMed Central

Tsukiji, Jun; Cho, Soo Jung; Echevarria, Ghislaine C.; Kwon, Sophia; Joseph, Phillip; Schenck, Edward J.; Naveed, Bushra; Prezant, David J.; Rom, William N.; Schmidt, Ann Marie; Weiden, Michael D.; Nolan, Anna

2014-01-01

Rationale Metabolic syndrome, inflammatory and vascular injury markers measured in serum after WTC exposures predict abnormal FEV1. We hypothesized that elevated LPA levels predict FEV1

A smoothed residual based goodness-of-fit statistic for nest-survival models

Treesearch

Rodney X. Sturdivant; Jay J. Rotella; Robin E. Russell

2008-01-01

Estimating nest success and identifying important factors related to nest-survival rates is an essential goal for many wildlife researchers interested in understanding avian population dynamics. Advances in statistical methods have led to a number of estimation methods and approaches to modeling this problem. Recently developed models allow researchers to include a...

Liver cancer risk, coffee, and hepatitis C virus infection: a nested case–control study in Japan

PubMed Central

Wakai, K; Kurozawa, Y; Shibata, A; Fujita, Y; Kotani, K; Ogimoto, I; Naito, M; Nishio, K; Suzuki, H; Yoshimura, T; Tamakoshi, A

2007-01-01

We examined hepatocellular carcinoma mortality in relation to coffee consumption and anti-hepatitis C virus (HCV) antibody seropositivity in a nested case–control study involving 96 cases. The multivariate-adjusted odds ratios (95% confidence interval) for daily coffee drinkers vs non-drinkers were 0.49 (0.25–0.96), 0.31 (0.11–0.85), and 0.75 (0.29–1.92) in all cases, in HCV-positive and in HCV-negative individuals, respectively. PMID:17637681

Effects of leafy spurge infestation on grassland birds

USGS Publications Warehouse

Scheiman, D.M.; Bollinger, E.K.; Johnson, D.H.

2003-01-01

Grassland bird populations are declining. Invasive plant species may be contributing to these declines by altering habitat quality. However, the effects of invasive plants on grassland birds are largely unknown. Leafy spurge (Euphorbia esula) is an exotic, invasive weed in the northern Great Plains. We examined the effects of leafy spurge infestation on densities of breeding birds, nest-site selection, and nest success in grasslands on the Sheyenne National Grassland (SNG), North Dakota, USA, 1999-2000. We categorized spurge-infested grasslands into 3 groups (low, medium, high), based on the area covered by spurge patches. We surveyed 75 100-m-radius circular points (25 in each group), and searched for nests in 6 16-ha plots (2 in each group). Grasshopper sparrow (Ammodramus savannarum) and savannah sparrow (Passerculus sandwichensis) densities were lower on high-spurge points than on low- and medium-spurge points. Bobolink (Dolichonyx oryzivorus) and western meadowlark (Sturnella neglecta) densities were not significantly different among spurge cover groups. Spurge cover did not appear to be an important factor in nest-site selection. However, western meadowlark nest success was positively associated with spurge cover. Vegetation structure is an important indicator of habitat quality and resource availability for grassland birds. Changes in vegetation structure caused by introduced plant species, such as spurge, can alter resource availability and hence affect bird community composition. Managers of spurge-infested grasslands should continue current spurge control measures to help prevent further declines in grassland habitat quality and grassland bird populations.

Alcohol consumption and PSA-detected prostate cancer risk—A case-control nested in the ProtecT study

PubMed Central

Zuccolo, Luisa; Lewis, Sarah J; Donovan, Jenny L; Hamdy, Freddie C; Neal, David E; Smith, George Davey

2013-01-01

Alcohol is an established carcinogen but not an established risk factor for prostate cancer, despite some recent prospective studies suggesting increased risk among heavy drinkers. The aim of this study was to investigate the role of alcohol on prostate-specific antigen (PSA) levels and prostate cancer risk. Two thousand four hundred PSA detected prostate cancer cases and 12,700 controls matched on age and general practice were identified through a case-control study nested in the PSA-testing phase of a large UK-based randomized controlled trial for prostate cancer treatment (ProtecT). Linear and multinomial logistic regression models were used to estimate ratios of geometric means (RGMs) of PSA and relative risk ratios (RRRs) of prostate cancer by stage and grade, with 95% confidence intervals (CIs), associated with weekly alcohol intake and drinking patterns. We found evidence of lower PSA (RGM 0.98, 95% CI: 0.98–0.99) and decreased risk of low Gleason-grade (RRR 0.96; 95%CI 0.93–0.99) but increased risk of high-grade prostate cancer (RRR 1.04; 95%CI 0.99–1.08; pdifference=0.004) per 10 units/week increase in alcohol consumption, not explained by current BMI, blood pressure, comorbidities, or reverse causation. This is the first large population-based study to find evidence of lower PSA levels for increasing alcohol consumption, with potential public health implications for the detection of prostate cancer. Our results also support a modestly higher risk of high-grade disease for heavy drinkers, but require independent replication to establish the nature of the association of alcohol with low-grade disease, preferably in cohorts with a heterogeneous case-mix. What's new? Alcohol is not an established risk factor for prostate cancer; however, the current work suggests that heavy drinking could cause a small increase in risk of the more aggressive forms. If the results are confirmed to be causal, prostate cancer risk will be added to the many long-term health risks of heavy drinking, and public health strategies will then also reduce high-risk, poorer prognosis prostate cancer. The authors also found that heavy drinkers have lower PSA levels, suggesting that heavy alcohol consumption could be used as a marker to identify men in whom some cancers might be missed. PMID:23024014

Prenatal Maternal Serum Concentrations of Per- and Polyfluoroalkyl Substances in Association with Autism Spectrum Disorder and Intellectual Disability.

PubMed

Lyall, Kristen; Yau, Vincent M; Hansen, Robin; Kharrazi, Martin; Yoshida, Cathleen K; Calafat, Antonia M; Windham, Gayle; Croen, Lisa A

2018-01-02

Emerging work has examined neurodevelopmental outcomes following prenatal exposure to per- and polyfluoroalkyl substances (PFAS), but few studies have assessed associations with autism spectrum disorder (ASD). Our objective was to estimate associations of maternal prenatal PFAS concentrations with ASD and intellectual disability (ID) in children. Participants were from a population-based nested case-control study of children born from 2000 to 2003 in southern California, including children diagnosed with ASD ( n =553), ID without autism ( n =189), and general population (GP) controls ( n =433). Concentrations of eight PFAS from stored maternal sera collected at 15-19 wk gestational age were quantified and compared among study groups. We used logistic regression to obtain adjusted odds ratios for the association between prenatal PFAS concentrations (parameterized continuously and as quartiles) and ASD versus GP controls, and separately for ID versus GP controls. Geometric mean concentrations of most PFAS were lower in ASD and ID groups relative to GP controls. ASD was not significantly associated with prenatal concentrations of most PFAS, though significant inverse associations were found for perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS) [adjusted ORs for the highest vs. lowest quartiles 0.62 (95% CI: 0.41, 0.93) and 0.64 (95% CI: 0.43, 0.97), respectively]. Results for ID were similar. Results from this large case-control study with prospectively collected prenatal measurements do not support the hypothesis that prenatal exposure to PFAS is positively associated with ASD or ID. https://doi.org/10.1289/EHP1830.

Environmental risks for nontuberculous mycobacteria. Individual exposures and climatic factors in the cystic fibrosis population.

PubMed

Prevots, D Rebecca; Adjemian, Jennifer; Fernandez, Aisling G; Knowles, Michael R; Olivier, Kenneth N

2014-09-01

Persons with cystic fibrosis are at high risk of pulmonary nontuberculous mycobacterial infection, with a national prevalence estimated at 13%. The risk of nontuberculous mycobacteria associated with specific environmental exposures, and the correlation with climatic conditions in this population has not been described. To describe the association of pulmonary nontuberculous mycobacteria with individual exposures to water and soil aerosols, and the population associations of these infections with climatic factors. We conducted a nested case-control study within a cohort study of pulmonary nontuberculous mycobacteria prevalence at 21 geographically diverse national cystic fibrosis centers. Incident nontuberculous mycobacterial infection cases (at least one prior negative culture followed by one positive culture) were age- and sex-matched to culture-negative controls. Exposures to water and soil were assessed by administering a standardized questionnaire. Cohort prevalence at each of the 21 centers was correlated with climatic conditions in the same area through linear regression modeling. Overall, 48 cases and 85 control subjects were enrolled. Indoor swimming was associated with incident infection (adjusted odds ratio, 5.9, 95% confidence interval, 1.3-26.1), although only nine cases (19%) and five control subjects (6%) reported indoor swimming in the 4 months prior to infection. Exposure to showering and municipal water supply was common among both cases and control subjects: 77% of cases and 76% of control subjects reported showering at least daily. In linear regression, average annual atmospheric water vapor content was significantly predictive of center prevalence (P = 0.0019), with R(2) = 0.40. Atmospheric conditions explain more of the variation in disease prevalence than individual behaviors. The risk of specific exposures may vary by geographic region due to differences in conditions favoring mycobacterial growth and survival. However, because exposure to these organisms is ubiquitous and behaviors are similar among persons with and without pulmonary nontuberculous mycobacteria, genetic susceptibility beyond cystic fibrosis is likely to be important for disease development. Common individual risk factors in high-risk populations remain to be identified.

Long-term psychosocial work environment and cardiovascular mortality among Swedish men.

PubMed Central

Johnson, J V; Stewart, W; Hall, E M; Fredlund, P; Theorell, T

1996-01-01

OBJECTIVES. This study examined the effect of cumulative exposure to work organization--psychological demands, work control, and social support on prospectively measured cardiovascular disease mortality risk. METHODS. The source population was a national sample of 12517 subjects selected from the Swedish male population by Statistics Sweden in annual surveys between 1977 and 1981. Over a 14-year follow-up period, 521 deaths from cardiovascular disease were identified. A nested case-control design was used. Work environment exposure scores were assigned to cases and controls by linking lifetime job histories with a job exposure matrix. RESULTS. Conditional logistic regression analysis was used in examining cardiovascular mortality risk in relation to work exposure after adjustment for age, year last employed, smoking, exercise, education, social class, nationality, and physical job demands. In the final multi-variable analysis, workers with low work control had a relative risk of 1.83 (95% confidence interval [CI] = 1.19, 2.82) for cardiovascular mortality. Workers with combined exposure to low control and low support had a relative risk of 2.62 (95% CI=1.22, 5.61). CONCLUSIONS. These results indicate that long-term exposure to low work control is a risk factor for cardiovascular disease mortality. PMID:8604756

Canada goose nest survival at rural wetlands in north-central Iowa

USGS Publications Warehouse

Ness, Brenna N.; Klaver, Robert W.

2016-01-01

The last comprehensive nest survival study of the breeding giant Canada goose (Branta canadensis maxima) population in Iowa, USA, was conducted >30 years ago during a period of population recovery, during which available nesting habitat consisted primarily of artificial nest structures. Currently, Iowa's resident goose population is stable and nests in a variety of habitats. We analyzed the effects of available habitat on nest survival and how nest survival rates compared with those of the expanding goose population studied previously to better understand how to maintain a sustainable Canada goose population in Iowa. We documented Canada goose nest survival at rural wetland sites in north-central Iowa. We monitored 121 nests in 2013 and 149 nests in 2014 at 5 Wildlife Management Areas (WMAs) with various nesting habitats, including islands, muskrat (Ondatra zibethicus) houses, and elevated nest structures. We estimated daily nest-survival rate using the nest survival model in Program MARK. Survival was influenced by year, site, stage, presence of a camera, nest age, and an interaction between nest age and stage. Nest success rates for the 28-day incubation period by site and year combination ranged from 0.10 to 0.84. Nest survival was greatest at sites with nest structures (β = 17.34). Nest survival was negatively affected by lowered water levels at Rice Lake WMA (2013 β = −0.77, nest age β = −0.07). Timing of water-level drawdowns for shallow lake restorations may influence nest survival rates.

Excess body iron and the risk of type 2 diabetes mellitus: a nested case-control in the PREDIMED (PREvention with MEDiterranean Diet) study.

PubMed

Arija, Victoria; Fernández-Cao, José C; Basora, Josep; Bulló, Mònica; Aranda, Nuria; Estruch, Ramón; Martínez-González, Miguel A; Salas-Salvadó, Jordi

2014-12-14

A prospective nested case-control study within the PREvention with MEDiterranean Diet (PREDIMED) was conducted to evaluate the relationship between excess body Fe (measured as serum ferritin (SF), soluble transferrin receptor (sTfR) and sTfR:ferritin ratio) and the risk of type 2 diabetes mellitus (T2DM) in a Mediterranean population at a high risk of CVD, without T2DM at the start of the study. The study contained 459 subjects, 153 with incident T2DM (cases) and 306 without incident T2DM (controls). The follow-up period was for 6.0 (interquartile range 3.9-6.5) years. For each incident diabetic subject, two subjects were selected as controls who were matched broadly for age as well as for sex, intervention group and BMI. We observed a relationship between SF values >257 μg/l in males and >139 μg/l in females and the risk of T2DM, following adjustment in the conditional logistic regression model for high-sensitivity C-reactive protein, fasting glucose and other components of the metabolic syndrome (OR 3.62, 95% CI 1.32, 19.95; P= 0.022). We also found an association between low sTfR:ferritin ratio levels and the incidence of T2DM (OR 3.02, 95% CI 1.09, 8.39; P= 0.042), but no association with sTfR (OR 1.29, 95% CI 0.51, 3.23; P= 0.722). Oxidative stress has been hypothesised to contribute to the development of insulin resistance and β-cell dysfunction, the two key events in the clinical development of T2DM. Following adjustment for other risk factors for T2DM, excess body Fe (measured as SF and sTfR:ferritin ratio) was associated with an increased risk of developing T2DM in a Mediterranean population at a high risk of CVD.

Marine turtles are not fussy nesters: a novel test of small-scale nest site selection using structure from motion beach terrain information

PubMed Central

Leon, Javier X.; Gilby, Ben L.; Olds, Andrew D.; Schlacher, Thomas A.

2017-01-01

Background Nest selection is widely regarded as a key process determining the fitness of individuals and viability of animal populations. For marine turtles that nest on beaches, this is particularly pivotal as the nesting environment can significantly control reproductive success.The aim of this study was to identify the environmental attributes of beaches (i.e., morphology, vegetation, urbanisation) that may be associated with successful oviposition in green and loggerhead turtle nests. Methods We quantified the proximity of turtle nests (and surrounding beach locations) to urban areas, measured their exposure to artificial light, and used ultra-high resolution (cm-scale) digital surface models derived from Structure-from-Motion (SfM) algorithms, to characterise geomorphic and vegetation features of beaches on the Sunshine Coast, eastern Australia. Results At small spatial scales (i.e., <100 m), we found no evidence that turtles selected nest sites based on a particular suite of environmental attributes (i.e., the attributes of nest sites were not consistently different from those of surrounding beach locations). Nest sites were, however, typically characterised by occurring close to vegetation, on parts of the shore where the beach- and dune-face was concave and not highly rugged, and in areas with moderate exposure to artificial light. Conclusion This study used a novel empirical approach to identify the attributes of turtle nest sites from a broader ‘envelope’ of environmental nest traits, and is the first step towards optimizing conservation actions to mitigate, at the local scale, present and emerging human impacts on turtle nesting beaches. PMID:28070454

Methodology for a randomised controlled trial of preschool vision screening. A new approach with the 'ALSPAC' project.

PubMed

Williams, C; Harrad, R A; Harvey, I; Frankel, S; Golding, J

1996-06-01

We present the methodology of a population-based Randomised Controlled Trial, comparing an intensive programme of primary preschool vision screening by orthoptists with the usual non-specialist screening. The aims of the trial are to compare the effectiveness and costs of intensive orthoptic screening with non-specialist measures. The orthoptic screening programme will be evaluated both as a composite package and in terms of the screening value of the individual tests at specific ages. This trial is nested within a large population-based longitudinal study. Additional demographic and developmental data on the children in the trial are therefore available. The results of the trial will be used to help clarify which methods of preschool ophthalmic population screening are best in terms of disease detection and cost efficiency.

Prediagnostic serum calcium and albumin and ovarian cancer: A nested case-control study in the Norwegian Janus Serum Bank Cohort.

PubMed

Schwartz, Gary G; Tretli, Steinar; Vos, Linda; Robsahm, Trude E

2017-08-01

Women with higher serum calcium may be more likely to be diagnosed and die of ovarian cancer. We evaluated that finding in a large, prospective cohort. We conducted a nested case-control study using a population-based biobank from Norway. We compared 202 ovarian cancer cases and 202 controls, matched for age, date at blood draw, and county of residence, with respect to serum calcium and albumin, adjusted for anthropometric variables. We evaluated risks using the entire follow-up period as well as 2-15 years and 16-25 years ("early" and "late", respectively). For the entire follow-up, risk was significantly increased in the highest tertile of albumin and for high albumin and calcium jointly. Risks for ovarian cancer differed markedly by follow-up time. In early follow-up, women in the highest tertile of serum calcium had a 2.5-fold increased risk, adjusted for height and body mass index (OR=2.47, 95% C.I. 1.12-5.45) with a significant dose-response (p=0.024). Risk was not elevated in late follow-up (OR=0.62, 95% C.I. 0.27-1.36). Similarly, in early follow-up, women in the highest tertile of serum albumin had an increased risk (OR=2.55, 95% C.I.1.22-5.49) with a significant dose-response (p=0.009). Conversely, risk was not increased in late follow-up (OR=1.36, 95% C.I. 0.65-2.83). These data confirm a prospective association between higher serum calcium and ovarian cancer. An association in early, but not late, follow-up suggests that the higher calcium reflects the presence of existing cancer. A positive association with serum albumin is novel and should be interpreted cautiously. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Red and processed meat consumption and risk of glioma in adults: A systematic review and meta-analysis of observational studies

PubMed Central

Saneei, Parvane; Willett, Walter; Esmaillzadeh, Ahmad

2015-01-01

Background: These findings from several observational studies, investigated the association between red meat consumption and gliomas, were inconsistent. We conducted a systematic review and meta-analysis of observational studies to summarize available date on the relation between meat intake and risk of glioma. Materials and Methods: A systematic literature search of relevant reports published until May 2014 of the PubMed/Medline, ISI Web of Knowledge, Excerpta Medica database, Ovid database, Google Scholar, and Scopus databases was conducted. From 723 articles yielded in the preliminary literature search, data from eighteen publications (14 case-control, three cohort, and one nested case-control study) on unprocessed red meat, processed meat, and/or total red meat consumption in relation to glioma in adults were included in the analysis. Quality assessment of studies was performed. Random effects model was used to conduct the meta-analysis. Results: We found a positive significant association between unprocessed red meat intake and risk of glioma (relative risk [RR] = 1.30; 95% confidence interval [CI]: 1.08-1.58) after excluding three studies with uncertain type of brain cancer. This analysis included only one cohort study which revealed no relation between unprocessed red meat intake and glioma (RR = 1.75; 95% CI: 0.35-8.77). Consumption of processed meats was not related to increased risk of glioma in population-based case-control studies (RR = 1.26; 95% CI: 1.05-1.51) and reduced risk in hospital-based case-controls (RR = 0.79; 95% CI: 0.65-0.97). No significant association was seen between processed red meat intake and risk of glioma in cohort studies (RR: 1.08; 95% CI: 0.84-1.37). Total red meat consumption was not associated with risk of adult glioma in case-control or cohort studies. Conclusion: In this meta-analysis of 18 observational studies, we found a modest positive association between unprocessed red meat intake and risk of gliomas based almost entirely on case-control studies. Processed red meat was overall not associated with risk of gliomas in case-control or cohort studies. PMID:26600837

Finnish Prenatal Study of Bipolar Disorders (FIPS-B): overview, design and description of the sample.

PubMed

Chudal, Roshan; Sucksdorff, Dan; Suominen, Auli; Lehti, Venla; Hinkka-Yli-Salomäki, Susanna; Huttunen, Jukka; Ristkari, Terja; Gissler, Mika; McKeague, Ian W; Brown, Alan S; Sourander, Andre

2014-04-01

Bipolar disorders (BPD) are chronic mental illnesses, the development of which involves genetic factors and environmental influences. The aim of this paper is to provide an overall description of the Finnish Prenatal Study of Bipolar Disorders (FIPS-B), including the study design, national registers and linkage of the registers. FIPS-B is a population-based prenatal epidemiological study of BPD with a nested case-control study design using several national registers. The registers used are: the Finnish Medical Birth Register (FMBR), the Finnish Hospital Discharge Register (FHDR), the Population Central Register and the Finnish Maternity Cohort (FMC), which are linked using the unique personal identity code (PIC). FIPS-B includes all children born from January 1, 1983 to December 31, 1998 and diagnosed with BPD in Finland by December 31, 2008. The total number of cases included in the FIPS-B is 1887. The age at first diagnosis ranged from 4 to 25 years. Half (50.4%) of the cases utilized only outpatient services, 12.7% only inpatient services and the rest (36.9%) utilized both services. Offspring of mothers with the lowest educational level had an increased odds of BPD (OR = 1.46, 95% CI 1.13-1.88). The cumulative incidence of BPD in the population aged 25 years or younger was 11.6/10,000 in 2008. FIPS-B has all the strengths of a register-based prenatal epidemiological study, along with the availability of maternal biomarkers, enabling it to examine several prenatal, perinatal and familial risk factors for BPD.

Trace elements in early phase type 2 diabetes mellitus-A population-based study. The HUNT study in Norway.

PubMed

Hansen, Ailin Falkmo; Simić, Anica; Åsvold, Bjørn Olav; Romundstad, Pål Richard; Midthjell, Kristian; Syversen, Tore; Flaten, Trond Peder

2017-03-01

Differences in trace elements levels between individuals with type 2 diabetes and controls have been reported in several studies in various body fluids and tissues, but results have been inconsistent. In order to examine trace element levels in the early phase of type 2 diabetes, we investigated the association between whole blood levels of 26 trace elements and the prevalence of previously undiagnosed, screening-detected type 2 diabetes. The study was conducted as a case-control study nested within the third survey of the population-based Nord-Trøndelag Health Study (HUNT3 Survey). Among participants without previously known diabetes, 128 cases of type 2 diabetes were diagnosed in people with a high diabetes risk score (FINDRISC≥15), and frequency-matched for age and sex with 755 controls. Blood samples were analyzed by high resolution inductively coupled plasma mass spectrometry. Associations between trace element levels and the prevalence of previously undiagnosed type 2 diabetes were evaluated with multivariable conditional logistic regression controlling for age, sex, body mass index, waist-to-hip ratio, education, income, smoking and family history of diabetes. The prevalence of previously undiagnosed type 2 diabetes increased across tertiles/quartiles for cadmium, chromium, iron, nickel, silver and zinc, and decreased with increasing quartiles of bromine (P trend <0.05). After corrections for multiple testing, associations for chromium remained significant (Q trend <0.05), while associations for iron and silver were borderline significant. No associations were found for arsenic, boron, calcium, cesium, copper, gallium, gold, indium, lead, magnesium, manganese, mercury, molybdenum, rubidium, selenium, strontium, tantalum, thallium and tin. Our results suggest a possible role of bromine, cadmium, chromium, iron, nickel, silver and zinc in the development of type 2 diabetes. Copyright © 2016 Elsevier GmbH. All rights reserved.

Maternal Infection during Pregnancy and Autism Spectrum Disorders

ERIC Educational Resources Information Center

Zerbo, Ousseny; Qian, Yinge; Yoshida, Cathleen; Grether, Judith K.; Van de Water, Judy; Croen, Lisa A.

2015-01-01

We conducted a nested case-control study including 407 cases and 2,075 frequency matched controls to investigate the association between maternal infections during pregnancy and risk of autism spectrum disorders (ASD). Cases, controls, and maternal infections were ascertained from Kaiser Permanente Northern California clinical databases. No…

Estimating nest detection probabilities for white-winged dove nest transects in Tamaulipas, Mexico

USGS Publications Warehouse

Nichols, J.D.; Tomlinson, R.E.; Waggerman, G.

1986-01-01

Nest transects in nesting colonies provide one source of information on White-winged Dove (Zenaida asiatica asiatica) population status and reproduction. Nests are counted along transects using standardized field methods each year in Texas and northeastern Mexico by personnel associated with Mexico's Office of Flora and Fauna, the Texas Parks and Wildlife Department, and the U.S. Fish and Wildlife Service. Nest counts on transects are combined with information on the size of nesting colonies to estimate total numbers of nests in sampled colonies. Historically, these estimates have been based on the actual nest counts on transects and thus have required the assumption that all nests lying within transect boundaries are detected (seen) with a probability of one. Our objectives were to test the hypothesis that nest detection probability is one and, if rejected, to estimate this probability.

Prevalence of non-organ-specific autoantibodies and chronic liver disease in the general population: a nested case-control study of the Dionysos cohort.

PubMed

Lenzi, M; Bellentani, S; Saccoccio, G; Muratori, P; Masutti, F; Muratori, L; Cassani, F; Bianchi, F B; Tiribelli, C

1999-09-01

Several retrospective and prospective studies report an increased prevalence of non-organ-specific autoantibodies (NOSAs) in patients with hepatitis C virus (HCV) related chronic liver disease (CLD). Some of the data so far available are controversial and the true prevalence of NOSAs in the general population is still not known. To explore the prevalence of NOSAs, their relation to different HCV genotypes, and the presence and severity of CLD in the general population of Northern Italy. All 226 anti-HCV positive and 87 hepatitis B surface antigen (HBsAg) positive patients of the Dionysos cohort study were analysed and compared with sex and age matched cases (226) negative for both anti-HCV antibody and HBsAg selected from the same cohort. Sera tested for the presence of NOSAs (anti-nuclear antibody (ANA), anti-smooth muscle antibody (SMA), and anti-liver/kidney microsomes type 1 antibody (LKM1)) were screened by indirect immunofluorescence at a 1:40 serum dilution. HCV RNA and HCV genotypes were also determined by nested polymerase chain reaction (PCR) of the 5' non-coding region and by PCR amplification of the core region with type specific primers. The overall prevalence of NOSA reactivity was significantly higher in anti-HCV positive subjects than in both normal and pathological controls (25% v 6% and 7% respectively, p<0.05). ANA, SMA, and LKM1 occurred in 16, 10, and 1. 3% of cases respectively. No specific association between NOSAs and a specific HCV genotype was found. NOSAs were found more often associated with more than one genotype (35.7%) and with untypable genotypes (34.6%), although the association was not statistically significant. NOSAs were associated with HCV RNA and CLD but not with the presence of cirrhosis and/or hepatocellular carcinoma. On univariate analysis, NOSA reactivity was independently associated with abnormal alanine aminotransferase (p<0.01) and gamma-glutamyltranspeptidase levels (p<0.05). The risk for the presence of NOSAs was 5.1 times higher in anti-HCV subjects than in controls. In the general population the prevalence of NOSAs is higher in anti-HCV positive subjects than in normal or disease controls. Moreover NOSAs are associated with CLD and with a more active disease in terms of alanine aminotransferase activity.

25-hydroxyvitamin D and breast cancer, colorectal cancer, and colorectal adenomas: case-control versus nested case-control studies.

PubMed

Grant, William B

2015-02-01

Existing literature includes concerns regarding reliability of case-control studies of breast cancer incidence with respect to 25-hydroxyvitamin D (25(OH)D) concentrations. For breast cancer, only case-control studies consistently find inverse correlations between 25(OH)D and breast cancer. However, for colorectal cancer, nested case-control studies find significant inverse correlations with respect to 25(OH)D concentrations at baseline for mean follow-up times of 7 years. This is a review of results currently existing in literature. I provide evidence that 25(OH)D concentration values are only useful for short follow-up times for breast cancer since it develops rapidly. To support the robust nature of breast cancer case-control studies, I show that results from 11 studies from seven countries align in a robust power-law fit to the odds ratio versus mean 25(OH)D concentrations. Case-control studies of breast cancer incidence rates provide reliable results. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Contextualising the Last Survivors: Population Structure of Marine Turtles in the Dominican Republic.

PubMed

Carreras, Carlos; Godley, Brendan J; León, Yolanda M; Hawkes, Lucy A; Revuelta, Ohiana; Raga, Juan A; Tomás, Jesús

2013-01-01

Nesting by three species of marine turtles persists in the Dominican Republic, despite historic threats and long-term population decline. We conducted a genetic survey of marine turtles in the Dominican Republic in order to link them with other rookeries around the Caribbean. We sequenced a 740bp fragment of the control region of the mitochondrial DNA of 92 samples from three marine turtle species [hawksbill (n = 48), green (n = 2) and leatherback (n = 42)], and incorporated published data from other nesting populations and foraging grounds. The leatherback turtle (Dermochelys coriacea) in the Dominican Republic appeared to be isolated from Awala-Yalimapo, Cayenne, Trinidad and St. Croix but connected with other Caribbean populations. Two distinct nesting populations of hawksbill turtles (Eremochelys imbricata) were detected in the Dominican Republic and exhibited interesting patterns of connectivity with other nesting sites and juvenile and adult male foraging aggregations. The green sea turtle (Chelonia mydas) has almost been extirpated from the Dominican Republic and limited inference could be made from our samples. Finally, results were compared with Lagrangian drifting buoys and published Lagrangian virtual particles that travelled through the Dominican Republic and Caribbean waters. Conservation implications of sink-source effects or genetic isolation derived from these complex inter-connections are discussed for each species and population.

Contextualising the Last Survivors: Population Structure of Marine Turtles in the Dominican Republic

PubMed Central

Carreras, Carlos; Godley, Brendan J.; León, Yolanda M.; Hawkes, Lucy A.; Revuelta, Ohiana; Raga, Juan A.; Tomás, Jesús

2013-01-01

Nesting by three species of marine turtles persists in the Dominican Republic, despite historic threats and long-term population decline. We conducted a genetic survey of marine turtles in the Dominican Republic in order to link them with other rookeries around the Caribbean. We sequenced a 740bp fragment of the control region of the mitochondrial DNA of 92 samples from three marine turtle species [hawksbill (n = 48), green (n = 2) and leatherback (n = 42)], and incorporated published data from other nesting populations and foraging grounds. The leatherback turtle (Dermochelys coriacea) in the Dominican Republic appeared to be isolated from Awala-Yalimapo, Cayenne, Trinidad and St. Croix but connected with other Caribbean populations. Two distinct nesting populations of hawksbill turtles (Eremochelys imbricata) were detected in the Dominican Republic and exhibited interesting patterns of connectivity with other nesting sites and juvenile and adult male foraging aggregations. The green sea turtle (Chelonia mydas) has almost been extirpated from the Dominican Republic and limited inference could be made from our samples. Finally, results were compared with Lagrangian drifting buoys and published Lagrangian virtual particles that travelled through the Dominican Republic and Caribbean waters. Conservation implications of sink-source effects or genetic isolation derived from these complex inter-connections are discussed for each species and population. PMID:23840394

Study designs may influence results: the problems with questionnaire-based case-control studies on the epidemiology of glioma.

PubMed

Johansen, Christoffer; Schüz, Joachim; Andreasen, Anne-Marie Serena; Dalton, Susanne Oksbjerg

2017-03-28

Glioma is a rare brain tumour with a very poor prognosis and the search for modifiable factors is intense. We reviewed the literature concerning risk factors for glioma obtained in case-control designed epidemiological studies in order to discuss the influence of this methodology on the observed results. When reviewing the association between three exposures, medical radiation, exogenous hormone use and allergy, we critically appraised the evidence from both case-control and cohort studies. For medical radiation and hormone replacement therapy (HRT), questionnaire-based case-control studies appeared to show an inverse association, whereas nested case-control and cohort studies showed no association. For allergies, the inverse association was observed irrespective of study design. We recommend that the questionnaire-based case-control design be placed lower in the hierarchy of studies for establishing cause-and-effect for diseases such as glioma. We suggest that a state-of-the-art case-control study should, as a minimum, be accompanied by extensive validation of the exposure assessment methods and the representativeness of the study sample with regard to the exposures of interest. Otherwise, such studies cannot be regarded as 'hypothesis testing' but only 'hypothesis generating'. We consider that this holds true for all questionnaire-based case-control studies on cancer and other chronic diseases, although perhaps not to the same extent for each exposure-outcome combination.

Population-specific demographic estimates provide insights into declines of Lark Buntings (Calamospiza melanocorys)

USGS Publications Warehouse

Yackel Adams, A.A.; Skagen, S.K.; Savidge, J.A.

2007-01-01

Many North American prairie bird populations have recently declined, and the causes of these declines remain largely unknown. To determine whether population limitation occurs during breeding, we evaluated the stability of a population of prairie birds using population-specific values for fecundity and postfledging survival. During 2001-2003, we radiomarked 67 female Lark Buntings (Calamospiza melanocorys) to determine annual fecundity and evaluate contributing factors such as nest survival and breeding response (number of breeding attempts and dispersal). Collectively, 67 females built 112 nests (1.67 ± 0.07 nests female−1 season−1; range: 1–3); 34 were second nests and 11 were third nests. Daily nest survival estimates were similar for initial and later nests with overall nest survival (DSR19) of 30.7% and 31.7%, respectively. Nest predation was the most common cause of failure (92%). Capture and radiomarking of females did not affect nest survival. Lark Bunting dispersal probabilities increased among females that fledged young from initial nests and females that lost their original nests late in the season. Conservative and liberal estimates of mean annual fecundity were 0.96 ±0.11 and 1.24 ± 0.09 female offspring per female, respectively. Given the fecundity and juvenile-survival estimates for this population, annual adult survival values of 71–77% are necessary to achieve a stable population. Because adult survival of prairie passerines ranges between 55% and 65%, this study area may not be capable of sustaining a stable population in the absence of immigration. We contrast our population assessment with one that assumes indirect values of fecundity and juvenile survival. To elucidate limiting factors, estimation of population-specific demographic parameters is desirable. We present an approach for selecting species and areas for evaluation of population stability.

Greater retention in care among adolescents on antiretroviral treatment accessing "Teen Club" an adolescent-centred differentiated care model compared with standard of care: a nested case-control study at a tertiary referral hospital in Malawi.

PubMed

MacKenzie, Rachel K; van Lettow, Monique; Gondwe, Chrissie; Nyirongo, James; Singano, Victor; Banda, Victor; Thaulo, Edith; Beyene, Teferi; Agarwal, Mansi; McKenney, Allyson; Hrapcak, Susan; Garone, Daniela; Sodhi, Sumeet K; Chan, Adrienne K

2017-11-01

There are numerous barriers to the care and support of adolescents living with HIV (ALHIV) that makes this population particularly vulnerable to attrition from care, poor adherence and virological failure. In 2010, a Teen Club was established in Zomba Central Hospital (ZCH), Malawi, a tertiary referral HIV clinic. Teen Club provides ALHIV on antiretroviral treatment (ART) with dedicated clinic time, sexual and reproductive health education, peer mentorship, ART refill and support for positive living and treatment adherence. The purpose of this study was to evaluate whether attending Teen Club improves retention in ART care. We conducted a nested case-control study with stratified selection, using programmatic data from 2004 to 2015. Cases (ALHIV not retained in care) and controls (ALHIV retained in care) were matched by ART initiation age group. Patient records were reviewed retrospectively and subjects were followed starting in March 2010, the month in which Teen Club was opened. Follow-up ended at the time patients were no longer considered retained in care or on 31 December 2015. Cases and controls were drawn from a study population of 617 ALHIV. Of those, 302 (48.9%) participated in at least two Teen Club sessions. From the study population, 135 (non-retained) cases and 405 (retained) controls were selected. In multivariable analyses, Teen Club exposure, age at the time of selection and year of ART initiation were independently associated with attrition. ALHIV with no Teen Club exposure were less likely to be retained than those with Teen Club exposure (adjusted odds ratio (aOR) 0.27; 95% CI 0.16, 0.45) when adjusted for sex, ART initiation age, current age, reason for ART initiation and year of ART initiation. ALHIV in the age group 15 to 19 were more likely to have attrition from care than ALHIV in the age group 10 to 14 years of age (aOR 2.14; 95% CI 1.12, 4.11). This study contributes to the limited evidence evaluating the effectiveness of service delivery interventions to support ALHIV within healthcare settings. Prospective evaluation of the Teen Club package with higher methodological quality is required for programmes and governments in low- and middle-income settings to prioritize interventions for ALHIV and determine their cost-effectiveness. © 2017 The Authors. Journal of the International AIDS Society published by John Wiley & sons Ltd on behalf of the International AIDS Society.

Risk factors for tuberculosis among health care workers in South India: a nested case-control study.

PubMed

Mathew, Anoop; David, Thambu; Thomas, Kurien; Kuruvilla, P J; Balaji, V; Jesudason, Mary V; Samuel, Prasanna

2013-01-01

The epidemiology of tuberculosis (TB) among health care workers (HCWs) in India remains under-researched. This study is a nested case-control design assessing the risk factors for acquiring TB among HCWs in India. It is a nested case-control study conducted at a tertiary teaching hospital in India. Cases (n = 101) were HCWs with active TB. Controls (n = 101) were HCWs who did not have TB, randomly selected from the 6,003 subjects employed at the facility. Cases and controls were compared with respect to clinical and demographic variables. The cases and controls were of similar age. Logistic regression analysis showed that body mass index (BMI) <19 kg/m(2) (odds ratio [OR]: 2.96, 95% confidence interval [CI]: 1.49-5.87), having frequent contact with patients (OR: 2.83, 95% CI: 1.47-5.45) and being employed in medical wards (OR: 12.37, 95% CI: 1.38-110.17) or microbiology laboratories (OR: 5.65, 95% CI: 1.74-18.36) were independently associated with increased risk of acquiring TB. HCWs with frequent patient contact and those with BMI <19 kg/m(2) were at high risk of acquiring active TB. Nosocomial transmission of TB was pronounced in locations, such as medical wards and microbiology laboratories. Surveillance of high-risk HCWs and appropriate infrastructure modifications may be important to prevent interpersonal TB transmission in health care facilities. Copyright © 2013 Elsevier Inc. All rights reserved.

Anticholinergic Exposure and Risk of Pneumonia in Persons with Alzheimer's Disease: A Nested Case-Control Study.

PubMed

Lampela, Pasi; Tolppanen, Anna-Maija; Tanskanen, Antti; Tiihonen, Jari; Hartikainen, Sirpa; Taipale, Heidi

2017-01-01

Risk of pneumonia is increased in persons with Alzheimer's disease (AD). In some studies, anticholinergic drugs (AC) have been associated with an increased pneumonia risk. We analyzed the risk of pneumonia associated with ACs in persons with AD. We performed a nested case-control study using register-based data from a Finnish nationwide MEDALZ cohort including all community-dwelling persons diagnosed with AD during 2005-2011. Cases were identified based on pneumonia diagnoses (n = 12,442) from hospital discharge and causes of death registers. Up to two controls without pneumonia were matched based on time since AD diagnoses, age, and gender for each case; AC use was measured using Anticholinergic Drug Scale. Use of AC was associated with an increased risk of pneumonia (adjusted odds ratio (OR) 1.36, 95% confidence interval (CI) 1.29-1.43). However, there was no increased pneumonia risk in persons using level 3 ACs. Incident use was associated with higher risk of pneumonia (OR 2.68, 95% CI 2.15-3.34) than prevalent use (OR 1.48, 95% CI 1.40-1.57). Among persons using cholinesterase inhibitors (AChEIs), risk of pneumonia was increased in persons using also ACs (OR 1.53, 95% CI 1.41-1.66). ACs were associated with an increased risk of pneumonia in persons with AD, especially at the time of initiation of these drugs. AC use was associated with increased pneumonia risk also in persons using AChEIs. This risk should be carefully considered when treating AD patients.

Whole-Blood Nested-PCR Amplification of M. leprae-Specific DNA for Early Diagnosis of Leprosy

PubMed Central

Wen, Yan; Xing, Yan; Yuan, Lian-Chao; Liu, Jian; Zhang, Ying; Li, Huan-Ying

2013-01-01

We evaluated the sensitivity and specificity of a nested-polymerase chain reaction (PCR) method for detection of Mycobacterium leprae DNA from whole blood. Whole-blood specimens were subjected to nested-PCR amplification of M. leprae repeat DNA sequences in 49 multibacillary (MB) and 30 paucibacillary (PB) leprosy patients, 96 household contacts (HHCs), 18 tuberculosis (TB) patients, and 35 normal healthy individuals. M. leprae DNA was detected in 95.92% (47/49) of MB, 70% (21/30) of PB, and 6.25% (6/96) of HHC, but it was not detected in 18 TB or 35 normal controls. The sensitivities of the anti-bovine serum albumin (ND-O-BSA) immunoglobulin M (IgM) and antifusion protein of ML0405-ML2331 IgG for MB were 97.96% and 89.8%, and these values for PB were 70% and 53.33%. However, the ND-O-BSA enzyme-linked immunosorbent assay (ELISA) had lower specificity, with relatively high false-positive results for TB patients (16.67%) and normal healthy controls (10%). Based on these promising findings, we propose the use of nested PCR of whole-blood samples along with ELISA test for early detection of leprosy cases. PMID:23478578

Managing individual nests promotes population recovery of a top predator

USGS Publications Warehouse

Cruz, Jennyffer; Windels, Steve K.; Thogmartin, Wayne E.; Crimmins, Shawn M.; Grim, Leland; Zuckerberg, Benjamin

2018-01-01

Threatened species are managed using diverse conservation tactics implemented at multiple scales ranging from protecting individuals, to populations, to entire species. Individual protection strives to promote recovery at the population‐ or species‐level, although this is seldom evaluated.After decades of widespread declines, bald eagles, Haliaeetus leucocephalus, are recovering throughout their range due to legal protection and pesticide bans. However, like other raptors, their recovery remains threatened by human activities. Bald eagle nests are commonly managed using buffer zones to minimize human disturbance, but the benefits of this practice remain unquantified.Within Voyageurs National Park (VNP), Minnesota, USA, managers have monitored bald eagle populations for over 40 years, and since 1991, have protected at‐risk nests from human disturbance using buffer zones (200 and 400 m radius). We aimed to (1) quantify the recovery of bald eagles in VNP (1973–2016), and (2) provide a first‐ever evaluation of the individual‐ and population‐level effects of managing individual nests. To do so, we developed Bayesian Integrated Population Models combining observations of nest occupancy and reproductive output (metrics commonly collected for raptors) to estimate nest‐level probabilities of occupancy, nest success, and high productivity (producing ≥2 nestlings), as well as population‐level estimates of abundance and growth.The breeding population of bald eagles at VNP increased steadily from <10 pairs in the late 1970s to 48 pairs by 2016. At the nest‐level, management significantly improved occupancy and success. At the population‐level, management led to 8% and 13% increases in nest success and productivity rates, respectively, resulting in a 37% increase in breeding pair abundance.Synthesis and applications. There is a clear need to evaluate how management approaches at multiple scales assist in species recovery. Our study uses an Integrated Population Model to reveal the population‐level benefits of a widely used, individual‐based management action (protecting nests using buffer zones) on a recovering raptor.

Influence of Polygenic Risk Scores on the Association Between Infections and Schizophrenia.

PubMed

Benros, Michael E; Trabjerg, Betina B; Meier, Sandra; Mattheisen, Manuel; Mortensen, Preben B; Mors, Ole; Børglum, Anders D; Hougaard, David M; Nørgaard-Pedersen, Bent; Nordentoft, Merete; Agerbo, Esben

2016-10-15

Several studies have suggested an important role of infections in the etiology of schizophrenia; however, shared genetic liability toward infections and schizophrenia could influence the association. We therefore investigated the possible effect of polygenic risk scores (PRSs) for schizophrenia on the association between infections and the risk of schizophrenia. We conducted a nested case-control study on a Danish population-based sample born after 1981 comprising of 1692 cases diagnosed with schizophrenia between 1994 and 2008 and 1724 matched controls. All individuals were linked utilizing nationwide population-based registers with virtually complete registration of all hospital contacts for infections. PRSs were calculated using discovery effect size estimates weights from an independent meta-analysis (34,600 cases and 45,968 control individuals). A prior hospital contact with infection had occurred in 41% of the individuals with schizophrenia and increased the incidence rate ratio (IRR) of schizophrenia by 1.43 (95% confidence interval [CI] = 1.22-1.67). Adding PRS, which was robustly associated with schizophrenia (by an IRR of 1.46 [95% CI = 1.34-1.60] per standard deviation of the score), did not alter the association with infections and the increased risk of schizophrenia remained (IRR = 1.41; 95% CI = 1.20-1.66). Furthermore, there were no interactions between PRS and infections on the risk of developing schizophrenia (p = .554). Neither did PRS affect the risk of acquiring infections among patients with schizophrenia (odds ratio = 1.00; 95% CI = 0.89-1.12) nor among controls (odds ratio = 1.09; 95% CI: 0.96-1.24). PRS and a history of infections have independent effects on the risk for schizophrenia, and the common genetic risk measured by PRS did not account for the association with infection in this sample. Copyright © 2016 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

Lung cancer among newspaper printers exposed to ink mist: a study of trade union members in Manchester, England.

PubMed Central

Leon, D A; Thomas, P; Hutchings, S

1994-01-01

A nested case-control study of lung cancer among men exposed to ink mist in newspaper production with rotary letterpress technology is presented. It is based within a historical cohort of 9232 printing workers in Manchester (1949-63). Men who operated newspaper rotary letterpress machines had a lung cancer standardised mortality ratio (SMR) of 179 (95% confidence interval (95% CI) 144-218) when compared with rates for England and Wales for the follow up period 1950-83. When adjustment was made for the higher rates in the local area, the SMR was reduced to 122 (95% CI 98-148). The nested case control study was based on 110 lung cancer cases (1949-86) and 316 matched controls. Duration of work in a rotary letterpress machine room was positively associated with risk of lung cancer (chi 2 linear trend = 3.30, p = 0.07); mean with 30 or more years duration of exposure had a risk of 1.73 (95% CI 0.94-3.17), relative to those with less than 20 years of exposure. Adjustment for period of first exposure in a machine room reduced the strength of the positive duration effect. The magnitude of the SMRs found in the cohort study could be explained by confounding with smoking. The duration effect seen in the case-control study, however, suggests that there may be a real effect of exposure to letterpress ink mists. This is biologically plausible, as benzo[a]pyrene, a known human carcinogen, has been found in appreciable concentrations in the atmosphere of rotary letterpress machine rooms. PMID:8111469

Monitoring and improving the sensitivity of dengue nested RT-PCR used in longitudinal surveillance in Thailand.

PubMed

Klungthong, Chonticha; Manasatienkij, Wudtichai; Phonpakobsin, Thipwipha; Chinnawirotpisan, Piyawan; Rodpradit, Prinyada; Hussem, Kittinun; Thaisomboonsuk, Butsaya; Ong-ajchaowlerd, Prapapun; Nisalak, Ananda; Kalayanarooj, Siripen; Buddhari, Darunee; Gibbons, Robert V; Jarman, Richard G; Yoon, In-Kyu; Fernandez, Stefan

2015-02-01

AFRIMS longitudinal dengue surveillance in Thailand depends on the nested RT-PCR and the dengue IgM/IgG ELISA. To examine and improve the sensitivity of the nested RT-PCR using a panel of archived samples collected during dengue surveillance. A retrospective analysis of 16,454 dengue IgM/IgG ELISA positive cases collected between 2000 and 2013 was done to investigate the sensitivity of the nested RT-PCR. From these cases, 318 acute serum specimens or extracted RNA, previously found to be negative by the nested RT-PCR, were tested using TaqMan real-time RT-PCR (TaqMan rRT-PCR). To improve the sensitivity of nested RT-PCR, we designed a new primer based on nucleotide sequences from contemporary strains found to be positive by the TaqMan rRT-PCR. Sensitivity of the new nested PCR was calculated using a panel of 87 samples collected during 2011-2013. The percentage of dengue IgM/IgG ELISA positive cases that were negative by the nested RT-PCR varied from 17% to 42% for all serotypes depending on the year. Using TaqMan rRT-PCR, dengue RNA was detected in 194 (61%) of the 318 acute sera or extracted RNA previously found to be negative by the nested RT-PCR. The newly designed DENV-1 specific primer increased the sensitivity of DENV-1 detection by the nested RT-PCR from 48% to 88%, and of all 4 serotypes from 73% to 87%. These findings demonstrate the impact of genetic diversity and signal erosion on the sensitivity of PCR-based methods. Published by Elsevier B.V.

Conservation hotspots for marine turtle nesting in the United States based on coastal development.

PubMed

Fuentes, Mariana M P B; Gredzens, Christian; Bateman, Brooke L; Boettcher, Ruth; Ceriani, Simona A; Godfrey, Matthew H; Helmers, David; Ingram, Dianne K; Kamrowski, Ruth L; Pate, Michelle; Pressey, Robert L; Radeloff, Volker C

2016-12-01

Coastal areas provide nesting habitat for marine turtles that is critical for the persistence of their populations. However, many coastal areas are highly affected by coastal development, which affects the reproductive success of marine turtles. Knowing the extent to which nesting areas are exposed to these threats is essential to guide management initiatives. This information is particularly important for coastal areas with both high nesting density and dense human development, a combination that is common in the United States. We assessed the extent to which nesting areas of the loggerhead (Caretta caretta), the green (Chelonia mydas), the Kemp's ridley (Lepidochelys kempii), and leatherback turtles (Dermochelys coriacea) in the continental United States are exposed to coastal development and identified conservation hotspots that currently have high reproductive importance and either face high exposure to coastal development (needing intervention), or have low exposure to coastal development, and are good candidates for continued and future protection. Night-time light, housing, and population density were used as proxies for coastal development and human disturbance. About 81.6% of nesting areas were exposed to housing and human population, and 97.8% were exposed to light pollution. Further, most (>65%) of the very high- and high-density nesting areas for each species/subpopulation, except for the Kemp's ridley, were exposed to coastal development. Forty-nine nesting sites were selected as conservation hotspots; of those high-density nesting sites, 49% were sites with no/low exposure to coastal development and the other 51% were exposed to high-density coastal development. Conservation strategies need to account for ~66.8% of all marine turtle nesting areas being on private land and for nesting sites being exposed to large numbers of seasonal residents. © 2016 by the Ecological Society of America.

Prediagnostic Helicobacter pylori Antibodies and Colorectal Cancer Risk in an Elderly, Caucasian Population.

PubMed

Blase, Jennifer L; Campbell, Peter T; Gapstur, Susan M; Pawlita, Michael; Michel, Angelika; Waterboer, Tim; Teras, Lauren R

2016-12-01

Study results on overall seroprevalence of Helicobacter pylori and colorectal cancer risk have been inconsistent. However, one study found positive associations with antibodies to specific H. pylori proteins. To follow up on those findings, we assessed associations of 15 H. pylori specific proteins with colorectal cancer incidence in the prospective Cancer Prevention Study-II Nutrition Cohort. Participants in this nested case-control study included 392 cases and 774 controls who were predominantly elderly (median age at blood draw: 71 years) and Caucasian (98%). Seroreactivity against 15 H. pylori proteins was assessed by fluorescent bead-based multiplex serology and associations with colorectal cancer were estimated using conditional logistic regression. Helicobacter pylori serostatus was not associated with colorectal cancer incidence (odds ratio (OR), 1.17, 95% confidence interval (95% CI), 0.91-1.50). Among individual antigens, GroEl serostatus was associated with colorectal cancer risk (OR, 1.32, 95% CI: 1.03-1.70), whereas CagM was associated with colon cancer risk only (OR, 1.35, 95% CI: 1.01-1.80). No dose-response relationships were observed for any of the antigens, including GroEl and CagM. The results of our study do not support an association between H. pylori infection and colorectal cancer risk in this elderly, mostly Caucasian population. © 2016 John Wiley & Sons Ltd.

Nests and nest sites of the San Miguel Island Song Sparrow

USGS Publications Warehouse

Kern, Michael D.; Sogge, Mark K.; Kern, Robert B.; van Riper, Charles

1993-01-01

Nests and nest sites of the San Miguel Island (SMI) Song Sparrow (Melospiza melodia micronyx) are described; nests are compared with those of 16 other races of Song Sparrows. Bush lupins (Lupinus albifrons), coyote brush (Baccharis pilularis) and golden bush (Haplopappus venetus) were the shrubs used most commonly as nest sites by Song Sparrows on SMI. As a result of its location, the nest was effectively concealed from gray foxes (Urocyon littoralis), the major predator of this sparrow. Nest and nest site also moderated the combined chilling effects of cool air temperatures and strong northwesterly winds on the eggs and nestlings. Even in the absence of these moderating effects of the nest site, the energetic cost of incubation, estimated at 41-53% of the sparrow's resting metabolic rate, was modest. Twenty-nine percent of the canopy above the nest was open and as much as 73% of the nest cup was in the sun at midday, a time when surface temperatures of foliage, nest and nestlings sometimes exceeded 40 C. Whereas this exposure did not apparently reduce fledging success, it may explain why the incidence of addled eggs was so high in this population of Song Sparrows compared to others. Significant differences existed among races of Song Sparrows in the size, porosity and insulation of the nest. In most cases, these differences were not related to the latitude of the races' nesting areas.

Impacts of Water Levels on Breeding Canada Geese and Methods for Mitigation and Management in the Southern Flathead Valley, Montana, 1983-1987 Final Report.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mackey, Dennis L.; Gregory, Shari K.; Matthews, William C. Jr.

Kerr Hydroelectric Dam is located at the south end of Flathead Lake, controls water levels on the lake and the Flathead River below the dam, and is currently operated as a load control facility. Current operation of Kerr Dam creates the greatest yearly water level fluctuations on both the lake and river during the Canada goose (Branta canadensis moffitti) brood and nesting period. Data collected from 1980-1982 indicated that goose nest numbers on the river were lower than during the 1950's, and that brood habitat on the lake may be limiting the goose population there. Our study was conducted frommore » 1983-1987 to determine the effects of Kerr Dam operation on Canada goose populations and habitat on the south half of Flathead Lake and the Flathead River, and to formulate management and mitigation recommendations. Nesting geese on the river appeared to be negatively affected by a lack of nest sites free from predators, and responded to available artificial nest structures with an increase in nest numbers and nesting success. Under current dam operation, river channel depths and widths do not discourage access to nesting islands by mammalian predators during some years and high predation on ground nests occurs. Intensively used brood areas on the lake and river were identified and described. Brood habitat on the lake was lower in quality and quantity than on the river due to dam operations. Gosling mortality on the lake was high, almost 2 times higher than on the river. Lake broods expended more energy obtaining food than river broods. Losses of brood habitat in the form of wet meadow marshes were documented and mitigation options developed. Management/mitigation alternatives and monitoring methods for nesting and brooding geese were identified.« less

Risk factors for Kaposi's sarcoma in human immunodeficiency virus patients after initiation of antiretroviral therapy: A nested case-control study in Kenya.

PubMed

Lupia, Rodgers; Wabuyia, Peter B; Otiato, Peter; Fang, Chi-Tai; Tsai, Feng-Jen

2017-12-01

This study aimed to evaluate the association between highly active antiretroviral therapy (HAART) adherence and development of Kaposi's sarcoma (KS) in human immunodeficiency virus (HIV)/AIDS patients. We conducted a retrospective nested case-control study of 165 participants (33 cases and 132 controls) receiving HAART care at Maseno Hospital, Kenya, from January 2005 to October 2013. Cases were HIV-positive adults with KS, who were matched with controls in a ratio of 1:4 based on age (±5 years of each case), sex, and KS diagnosis date. Perfect adherence to HAART was assessed on every clinic visit by patients' self-reporting and pill counts. Chi-square tests were performed to compare socioeconomic and clinical statuses between cases and controls. A conditional logistic regression was used to assess the effects of perfect adherence to HAART, the latest CD4 count, education level, distance to health-care facility, initial World Health Organization stage, and number of regular sexual partners on the development of KS. Only 63.6% participants reported perfect adherence, and the control group had a significantly higher percentage of perfect adherence (75.0%) than did cases (18.2%). After adjustment for potential imbalances in the baseline and clinical characteristics, patients with imperfect HAART adherence had 20-times greater risk of developing KS than patients with perfect HAART adherence [hazard ratios: 21.0, 95% confidence interval: 4.2-105.1]. Patients with low latest CD4 count (≤350 cells/mm 3 ) had a seven-times greater risk of developing KS than did their counterparts (HRs: 7.1, 95% CI: 1.4-36.2). Imperfect HAART adherence and low latest CD4 count are significantly associated with KS development. Copyright © 2015. Published by Elsevier B.V.

Do mature forest birds prefer early-successional habitat during the post-fledging period?

Treesearch

Carlin C. Chandler; David I. King; Richard B. Chandler

2012-01-01

Recent studies have highlighted the importance of the post-fledging period to bird populations, suggesting that the importance of this portion of the life cycle is equal to or greater than the nesting period. Nevertheless, few studies have compared abundance of forest nesting species between mature forest and early-successional habitats while controlling for...

Factors influencing attempted and completed suicide in postnatal women: A population-based study in Taiwan.

PubMed

Weng, Shu-Chuan; Chang, Jung-Chen; Yeh, Ming-Kung; Wang, Shun-Mu; Chen, Yi-Hua

2016-05-12

The aims of study were to investigate risk factors associated with attempted and completed suicide. This nested case-control study was conducted using the medical and death data of nearly all pregnant women for the period 2002-2012 in Taiwan. A total of 139 cases of attempted suicide and 95 cases of completed suicide were identified; for each case, 10 controls were randomly selected and matched to the cases according to age and year of delivery. A conditional logistic regression model was used. The mean attempted and completed suicide rates were 9.91 and 6.86 per 100,000 women with live births, respectively. Never having married and postpartum depression also increased the risk of attempted suicide (OR = 2.06; 95% CI = 1.09-3.88 and OR = 2.51; 95% CI = 1.10-5.75, respectively) and completed suicide (OR = 20.27; 95% CI = 8.99-45.73 and OR = 21.72; 95% CI = 8.08-58.37, respectively). Other factors for attempted suicide included being widowed or divorced, and having a caesarean delivery or suicide history. Other factors for completed suicide included lower education level, low infant birth weight, and diagnosis of anxiety or mood disorder. These results suggest that people should appropriately assess potential risk factors and provide assistance for postnatal women to reduce the occurrence of suicide events.

Population trends and survival of nesting green sea turtles Chelonia mydas on Aves Island, Venezuela

USGS Publications Warehouse

Garcia-Cruz, Marco A.; Lampo, Margarita; Peñaloza, Claudia L.; Kendall, William L.; Solé, Genaro; Rodriguez-Clark, Kathryn M.

2015-01-01

Long-term demographic data are valuable for assessing the effect of anthropogenic impacts on endangered species and evaluating recovery programs. Using a 2-state open robust design model, we analyzed mark-recapture data from green turtles Chelonia mydas sighted between 1979 and 2009 on Aves Island, Venezuela, a rookery heavily impacted by human activities before it was declared a wildlife refuge in 1972. Based on the encounter histories of 7689 nesting females, we estimated the abundance, annual survival, and remigration intervals for this population. Female survival varied from 0.14-0.91, with a mean of 0.79, which is low compared to survival of other populations from the Caribbean (mean = 0.84) and Australia (mean = 0.95), even though we partially corrected for tag loss, which is known to negatively bias survival estimates. This supports prior suggestions that Caribbean populations in general, and the Aves Island population in particular, may be more strongly impacted than populations elsewhere. It is likely that nesters from this rookery are extracted while foraging in remote feeding grounds where hunting still occurs. Despite its relatively low survival, the nesting population at Aves Island increased during the past 30 years from approx. 500 to >1000 nesting females in 2009. Thus, this population, like others in the Caribbean and the Atlantic, seems to be slowly recovering following protective management. Although these findings support the importance of long-term conservation programs aimed at protecting nesting grounds, they also highlight the need to extend management actions to foraging grounds where human activities may still impact green turtle populations.

Breeding biology and nest-site selection of red-tailed hawks in an altered desert grassland

USGS Publications Warehouse

Hobbs, R.J.; DeStefano, S.; Halvorson, W.L.

2006-01-01

Red-tailed Hawks (Buteo jamaicensis) have expanded their range as trees have invaded formerly-open grasslands. Desert grasslands of southern Arizona have been invaded by mesquite trees (Prosopis velutina) since Anglo-American settlement and now support a large population of Red-tailed Hawks. We studied a population of Red-tailed Hawks in an altered desert grassland in southern Arizona. Our objectives were to determine what environmental characteristics influence Red-tailed Hawk habitat selection in mesquite-invaded desert grasslands and to evaluate the habitat quality of these grasslands for Red-tailed Hawks based on nesting density, nest success, and productivity. Red-tailed Hawks had 86% (95% C.I. = 73-99) nest success and 1.82 young per breeding pair (95% C.I. = 1.41-2.23). Nesting density was 0.15 (95% CI = 0.08-0.21) breeding pairs/km2 and the mean nearest-neighbor distance was 1.95 km (95% C.I. = 1.74-2.16). Red-tailed Hawks selected nest-sites with taller nest-trees and greater tree height and cover than were available at random. Mesquite trees in desert grasslands provide abundant potential nesting structures for Red-tailed Hawks. ?? 2006 The Raptor Research Foundation, Inc.

Reproductive synchrony in a recovering bottlenecked sea turtle population.

PubMed

Plot, Virginie; de Thoisy, Benoît; Blanc, Stéphane; Kelle, Laurent; Lavergne, Anne; Roger-Bérubet, Hélène; Tremblay, Yann; Fossette, Sabrina; Georges, Jean-Yves

2012-03-01

1. The assessment of species extinction risk has been well established for some time now. Assessing the potential for recovery in endangered species is however much more challenging, because complementary approaches are required to detect reliable signals of positive trends. 2. This study combines genetics, demography and behavioural data at three different time-scales to assess historical and recent population changes and evidence of reproductive synchrony in a small population of olive ridley sea turtle Lepidochelys olivacea. Lepidochelys is considered as the most extraordinary example of reproductive synchrony in reptiles, yet to date, it has only been reported in large populations. 3. Using Bayesian coalescent-based models on microsatellite nuclear DNA variability, we demonstrate that effective population size in olive ridleys nesting in French Guiana has dramatically declined by 99% over the last 20 centuries. This low current population size is further illustrated by the absence of genetic mitochondrial DNA diversity in the present nesting population. Yet, monitoring of nesting sites in French Guiana suggests a possible recovery of the population over the last decade. 4. Satellite telemetry shows that over the first 14 days of their 28-days inter-nesting interval, i.e. when eggs maturation is likely to occur, gravid females disperse over the continental shelf. They then gather together with a striking spatiotemporal consistency close to the nesting site, where they later emerge for their second nesting event. 5. Our results therefore suggest that reproductive synchrony also occurs in small populations. Olive ridleys may ensure this synchrony by adjusting the duration of the second half of their inter-nesting interval prior to landing, possibly through social mediation. 6. Such reproductive synchrony may be related to the maintenance of some species-specific strategy despite former collapse and may contribute to the present population recovery. The gregarious behaviour of reproductive individuals close to shore where human-induced perturbations occur is however a cause for conservation concern for this still poorly known species. © 2011 The Authors. Journal of Animal Ecology © 2011 British Ecological Society.

Effects of schistosomiasis on susceptibility to HIV-1 infection and HIV-1 viral load at HIV-1 seroconversion: A nested case-control study.

PubMed

Downs, Jennifer A; Dupnik, Kathryn M; van Dam, Govert J; Urassa, Mark; Lutonja, Peter; Kornelis, Dieuwke; de Dood, Claudia J; Hoekstra, Pytsje; Kanjala, Chifundo; Isingo, Raphael; Peck, Robert N; Lee, Myung Hee; Corstjens, Paul L A M; Todd, Jim; Changalucha, John M; Johnson, Warren D; Fitzgerald, Daniel W

2017-09-01

Schistosomiasis affects 218 million people worldwide, with most infections in Africa. Prevalence studies suggest that people with chronic schistosomiasis may have higher risk of HIV-1 acquisition and impaired ability to control HIV-1 replication once infected. We hypothesized that: (1) pre-existing schistosome infection may increase the odds of HIV-1 acquisition and that the effects may differ between men and women, and (2) individuals with active schistosome infection at the time of HIV-1 acquisition may have impaired immune control of HIV-1, resulting in higher HIV-1 viral loads at HIV-1 seroconversion. We conducted a nested case-control study within a large population-based survey of HIV-1 transmission in Tanzania. A population of adults from seven villages was tested for HIV in 2007, 2010, and 2013 and dried blood spots were archived for future studies with participants' consent. Approximately 40% of this population has Schistosoma mansoni infection, and 2% has S. haematobium. We tested for schistosome antigens in the pre- and post-HIV-1-seroconversion blood spots of people who acquired HIV-1. We also tested blood spots of matched controls who did not acquire HIV-1 and calculated the odds that a person with schistosomiasis would become HIV-1-infected compared to these matched controls. Analysis was stratified by gender. We compared 73 HIV-1 seroconverters with 265 controls. Women with schistosome infections had a higher odds of HIV-1 acquisition than those without (adjusted OR = 2.8 [1.2-6.6], p = 0.019). Schistosome-infected men did not have an increased odds of HIV-1 acquisition (adjusted OR = 0.7 [0.3-1.8], p = 0.42). We additionally compared HIV-1 RNA levels in the post-seroconversion blood spots in HIV-1 seroconverters with schistosomiasis versus those without who became HIV-infected in 2010, before antiretroviral therapy was widely available in the region. The median whole blood HIV-1 RNA level in the 15 HIV-1 seroconverters with schistosome infection was significantly higher than in the 22 without schistosomiasis: 4.4 [3.9-4.6] log10 copies/mL versus 3.7 [3.2-4.3], p = 0.017. We confirm, in an area with endemic S. mansoni, that pre-existing schistosome infection increases odds of HIV-1 acquisition in women and raises HIV-1 viral load at the time of HIV-1 seroconversion. This is the first study to demonstrate the effect of schistosome infection on HIV-1 susceptibility and viral control, and to differentiate effects by gender. Validation studies will be needed at additional sites.

Coffee intake and gastric cancer risk: The Singapore Chinese Health Study

PubMed Central

Ainslie-Waldman, Cheryl E.; Koh, Woon-Puay; Jin, Aizhen; Yeoh, Khay Guan; Zhu, Feng; Wang, Renwei; Yuan, Jian-Min; Butler, Lesley M.

2014-01-01

Background Despite experimental evidence showing chemopreventive effects of coffee-related compounds on gastric carcinogenesis, epidemiologic studies generally do not support coffee-gastric cancer associations. Observational data are lacking among high-risk populations with sufficient regular coffee consumption. Methods We examined the association between caffeinated coffee intake and gastric cancer risk in a population-based cohort that enrolled 63,257 Chinese men and women aged 45–74 years between 1993 and 1998 in Singapore. Incident gastric cancer cases (n=647) were identified after a mean follow-up of 14.7 years. Biomarkers of Helicobacter pylori (H. pylori) infection were measured in a subset of gastric cancer cases with blood collected prior to cancer diagnosis and their matched controls. Results In the total cohort, daily versus non-daily coffee intake was associated with a statistically non-significant decrease in gastric cancer risk [hazards ratio (HR) = 0.85; 95% confidence interval (CI): 0.69, 1.04). In women, the inverse association strengthened and reached statistical significance (HR=0.63; 95% CI: 0.46, 0.87). In analyses restricted to never smokers and nondrinkers of alcohol, inverse associations strengthened in the total cohort (HR=0.69; 95% CI: 0.52, 0.91) and in women (HR=0.52; 95% CI: 0.37, 0.74). There was no coffee-gastric cancer risk association among men, regardless of smoking status or alcohol consumption. Similar results were observed in the nested case-control study after adjustment for H. pylori infection. Conclusion Daily coffee consumption may reduce the risk of gastric cancer in high-risk populations, especially among women. Impact: Research aimed at identifying the compounds in coffee that may protect against gastric carcinogenesis is warranted. PMID:24608187

Coffee intake and gastric cancer risk: the Singapore Chinese health study.

PubMed

Ainslie-Waldman, Cheryl E; Koh, Woon-Puay; Jin, Aizhen; Yeoh, Khay Guan; Zhu, Feng; Wang, Renwei; Yuan, Jian-Min; Butler, Lesley M

2014-04-01

Despite experimental evidence showing chemopreventive effects of coffee-related compounds on gastric carcinogenesis, epidemiologic studies generally do not support coffee-gastric cancer associations. Observational data are lacking among high-risk populations with sufficient regular coffee consumption. We examined the association between caffeinated coffee intake and gastric cancer risk in a population-based cohort that enrolled 63,257 Chinese men and women ages 45 to 74 years between 1993 and 1998 in Singapore. Incident gastric cancer cases (n = 647) were identified after a mean follow-up of 14.7 years. Biomarkers of Helicobacter pylori (H. pylori) infection were measured in a subset of gastric cancer cases with blood collected before cancer diagnosis and their matched controls. In the total cohort, daily versus nondaily coffee intake was associated with a statistically nonsignificant decrease in gastric cancer risk [HR = 0.85; 95% confidence interval (CI), 0.69-1.04]. In women, the inverse association strengthened and reached statistical significance (HR = 0.63; 95% CI, 0.46-0.87). In analyses restricted to never smokers and nondrinkers of alcohol, inverse associations strengthened in the total cohort (HR = 0.69; 95% CI, 0.52-0.91) and in women (HR = 0.52; 95% CI, 0.37-0.74). There was no coffee-gastric cancer risk association among men, regardless of smoking status or alcohol consumption. Similar results were observed in the nested case-control study after adjustment for H. pylori infection. Daily coffee consumption may reduce the risk of gastric cancer in high-risk populations, especially among women. Research aimed at identifying the compounds in coffee that may protect against gastric carcinogenesis is warranted.

Urban waterfowl population: Ecological evaluation of management and planning

NASA Astrophysics Data System (ADS)

Greer, David M.

1982-05-01

An urban population of ducks in Puyallup, Washington, USA was studied for 14 consecutive months beginning in November 1978. Observations were made weekly from four study sites where ducks would congregate at early morning hours. Factors contributing to the presence of waterfowl in Puyallyup included abundant food supplies and a creek corridor that connected fragmented habitats in the urban area to the larger rural populations of waterfowl. Mallards ( Anas platyrhynchos) were the most abundant of the 13 species observed and were the only ducks remaining during the nesting season. Habitat size and complexity were important factors influencing the species diversity of a particular site. Nesting success of mallards was poor due to limited distribution of nesting habitat, intraspecific aggression, and human disturbance. Both site-specific and more broad-based strategies are suggested for managing and planning for duck populations in urban areas.

Genetic structure of Florida green turtle rookeries as indicated by mitochondrial DNA control region sequences

USGS Publications Warehouse

Shamblin, Brian M.; Bagley, Dean A.; Ehrhart, Llewellyn M.; Desjardin, Nicole A.; Martin, R. Erik; Hart, Kristen M.; Naro-Maciel, Eugenia; Rusenko, Kirt; Stiner, John C.; Sobel, Debra; Johnson, Chris; Wilmers, Thomas; Wright, Laura J.; Nairn, Campbell J.

2014-01-01

Green turtle (Chelonia mydas) nesting has increased dramatically in Florida over the past two decades, ranking the Florida nesting aggregation among the largest in the Greater Caribbean region. Individual beaches that comprise several hundred kilometers of Florida’s east coast and Keys support tens to thousands of nests annually. These beaches encompass natural to highly developed habitats, and the degree of demographic partitioning among rookeries was previously unresolved. We characterized the genetic structure of ten Florida rookeries from Cape Canaveral to the Dry Tortugas through analysis of 817 base pair mitochondrial DNA (mtDNA) control region sequences from 485 nesting turtles. Two common haplotypes, CM-A1.1 and CM-A3.1, accounted for 87 % of samples, and the haplotype frequencies were strongly partitioned by latitude along Florida’s Atlantic coast. Most genetic structure occurred between rookeries on either side of an apparent genetic break in the vicinity of the St. Lucie Inlet that separates Hutchinson Island and Jupiter Island, representing the finest scale at which mtDNA structure has been documented in marine turtle rookeries. Florida and Caribbean scale analyses of population structure support recognition of at least two management units: central eastern Florida and southern Florida. More thorough sampling and deeper sequencing are necessary to better characterize connectivity among Florida green turtle rookeries as well as between the Florida nesting aggregation and others in the Greater Caribbean region.

Long-term lesser prairie-chicken nest ecology in response to grassland management

USGS Publications Warehouse

Fritts, Sarah R.; Grisham, Blake A.; Haukos, David A.; Boal, Clint W.; Patten, Michael; Wolfe, Don H.; Dixon, Charles; Cox, Robert D.; Heck, Willard R.

2016-01-01

Long-term population and range declines from habitat loss and fragmentation caused the lesser prairie-chicken (Tympanuchus pallidicinctus) to be a species of concern throughout its range. Current lesser prairie-chicken range in New Mexico and Texas is partially restricted to sand shinnery oak (Quercus havardii; hereafter shinnery oak) prairies, on which cattle grazing is the main socioeconomic driver for private landowners. Cattle producers within shinnery oak prairies often focus land management on shrub eradication using the herbicide tebuthiuron to promote grass production for forage; however, herbicide application alone, and in combination with grazing, may affect nest site selection and nest survival of lesser prairie-chickens through the reduction of shinnery oak and native grasses. We used a controlled, paired, completely randomized design study to assess the influence of grazing and tebuthiuron application and their combined use on nest site selection and nest survival from 2001 to 2010 in Roosevelt County, New Mexico, USA at 2 spatial scales (i.e., treatment and microhabitat) in 4 treatments: tebuthiuron with grazing, tebuthiuron without grazing, no tebuthiuron with grazing, and a control of no tebuthiuron and no grazing. Grazing treatment was a short-duration system in which plots were grazed once during the dormant season and once during the growing season. Stocking rate was calculated each season based on measured forage production and applied to remove ≤25% of available herbaceous material per season. At the treatment scale, we compared nest site selection among treatments using 1-way χ2 tests and nest survival among treatments using a priori candidate nest survival models in Program MARK. At the microhabitat scale, we identified important habitat predictors of nest site selection and nest survival using logistic regression and a priori candidate nest survival models in Program MARK, respectively. Females typically used treatments as expected and we did not detect trends in selection. Nest survival did not differ among treatments. At the microhabitat scale, nest sites had less bare ground (P = 0.001) and greater angles of obstruction (P ≤ 0.001) compared to random sites. There was a high degree of model selection uncertainty among our candidate models at the microhabitat scale and survival estimates were similar among habitat covariates. Results suggest a tebuthiuron application rate of 0.60 kg/ha, short-duration grazing, and a combination of these management techniques were not detrimental to lesser prairie-chicken nest site selection or nest survival. However, intensified management that increases bare ground or reduces overhead cover may negatively affect lesser prairie-chicken nesting habitat and nest survival.

Serological and molecular diagnosis of Toxoplasma gondii in patients with schizophrenia.

PubMed

Ebrahimzadeh, Adel; Shahraki, Mehdi Khoshsima; Mohammadi, Azad

2018-06-01

Schizophrenia is a persistent neuropsychiatric syndrome of uncertain source. Toxoplasmosis is the most prevalent parasitic protozoan infecting one-third of the worldwide human population. Infectious agents such as toxoplasma are the probable cause of schizophrenia. This study was aimed to evaluate the association between schizophrenia and toxoplasmosis using SAG1 and B1 Target gene. During February to December 2016, 92 patients with schizophrenia are imported in our study. All cases were assessed by serological (IgG and IgM antibodies) and molecular examinations. ELISA was performed by Commercial kits according to manufactures procedure. DNA was extracted and nested PCR was done using two pairs of primers. From 92 patients, 59 (64.13%) cases were positive for toxoplasmosis by serological examinations (14 samples positive for IgM and IgG, 40 samples positive for only IgG and 5 samples Positive for only IgM) and 58 (63.04%) were positive by Nested PCR technique. Based on the nested PCR method, 68.47 and 47.82% of samples were positive by B1 and SAG1 genes, respectively. Our results showed the importance of use both serological and molecular diagnostic methods for accurate recognition of T . gondii in patients with schizophrenia. Moreover our results indicated that B1 gene is more sensitive than SAG1 gene.

Physical and Organizational Job Stressors in Pregnancy and Associations With Primary Cesarean Deliveries.

PubMed

Guendelman, Sylvia; Gemmill, Alison; Hosang, Nap; MacDonald, Leslie A

2017-06-01

The aim of this study was to assess the relationship between exposure to physical and organizational job stressors during pregnancy and cesarean delivery. We sampled 580 employed women in California who participated in a nested population-based case-control study of birth outcomes. Adjusted multivariate regression analyses estimated associations between heavy lifting, frequent bending, high noise, extreme temperature, prolonged standing and organizational stressors (shift work, inflexible schedules, effort-reward ratio), and primary cesarean (vs vaginal) delivery, controlling for covariates. Women occupationally exposed had higher odds of cesarean. Those exposed to daily manual lifting more than 15 pounds [adjusted odds ratio = 2.54; 95% confidence interval (95% CI) 1.21 to 5.32] and at least four physical job stressors (adjusted odds ratio = 3.49; 95% CI 1.21 to 10.09) had significantly elevated odds of cesarean delivery. Exposed morbid women experienced greater risk; risk was lower among those with schedule flexibility. Associations were found between modifiable exposure to physical job stressors during pregnancy and cesarean delivery.

An energy-circuit population model for great egrets (Ardea alba) at Lake Okeechobee, Florida, U.S.A

USGS Publications Warehouse

Smith, Jeff P.

1997-01-01

I simulated the annual population cycles of Great Egrets (Ardea alba) at Lake Okeechobee, Florida, to provide a framework for evaluating the local population dynamics of nesting and foraging wading birds. The external forcing functions were solar energy, minimum air temperature, water depth, surface-water drying rate, and season. Solar input controlled the production of prey at moderate to high lake stages, but water area exerted primary control during a two-year drought. Modeling prey production as a linear function of water area resulted in underestimation of prey density during the drought, suggesting that prey organisms maintained high fecundity while concentrated in submerged vegetation at the lakeward fringe of the littoral zone. Simulation confirmed that large influxes of wading birds during the drought were the combined result of a regional refuge response and the availability of concentrated prey. Modeling immigration and emigration as primarily functions of the surface-water drying rate, rather than lake stage, resulted in a closer match of observed and simulated population trends for foraging birds, suggesting that the pattern of surface-water fluctuations was a more important factor than water depth. Simulation indicated an abrupt-threshold response rather than a linear association between foraging efficiency and low temperatures, which reduce activity levels of forage fishes. Great Egret breeder recruitment is primarily a function of prey availability, climate, and hydrologic trends, but simulation confirmed the concurrent involvement of a seasonal or physiological-readiness factor. An attractor function driven by high winter lake stages was necessary to reproduce observed patterns of breeder recruitment, suggesting that Great Egrets initiate nesting based on environmental cues that lead to peak food availability when nestlings are present. Poor correspondence of reproductive effort and nest productivity suggested that the drought compromised the birds' predictive abilities. The need to model breeder recruitment as a function of a maximum rate rather than the size of the local foraging population suggested that birds may nest on the lake even though on-lake foraging conditions are poor. Simulated and observed estimates of egg and hatching production did not match, suggesting that the causes of failure during incubation were complex or more localized than could be accounted for with lakewide hydrologic and climatic data. A forced increase in prey consumption of 12% was necessary to reproduce observed, high levels of nest productivity in 1990, which corresponded to the finding that panhandled fish constituted 10–12% of the biomass fed to Great Egret nestlings that year.

Decision-making in honeybee swarms based on quality and distance information of candidate nest sites.

PubMed

Laomettachit, Teeraphan; Termsaithong, Teerasit; Sae-Tang, Anuwat; Duangphakdee, Orawan

2015-01-07

In the nest-site selection process of honeybee swarms, an individual bee performs a waggle dance to communicate information about direction, quality, and distance of a discovered site to other bees at the swarm. Initially, different groups of bees dance to represent different potential sites, but eventually the swarm usually reaches an agreement for only one site. Here, we model the nest-site selection process in honeybee swarms of Apis mellifera and show how the swarms make adaptive decisions based on a trade-off between the quality and distance to candidate nest sites. We use bifurcation analysis and stochastic simulations to reveal that the swarm's site distance preference is moderate>near>far when the swarms choose between low quality sites. However, the distance preference becomes near>moderate>far when the swarms choose between high quality sites. Our simulations also indicate that swarms with large population size prefer nearer sites and, in addition, are more adaptive at making decisions based on available information compared to swarms with smaller population size. Copyright © 2014 Elsevier Ltd. All rights reserved.

Allergy is associated with suicide completion with a possible mediating role of mood disorder - a population-based study.

PubMed

Qin, P; Mortensen, P B; Waltoft, B L; Postolache, T T

2011-05-01

With increasing research suggesting a role of allergy on suicidality, this study, on a population level, delved into how allergy affects risk for suicide completion in the context of mood disorder and other factors. Based on the entire population of Denmark, we included 27,096 completed suicides and 467,571 live controls matched on sex and age with a nested case-control design. We retrieved personal information on hospital contacts for allergy and other variables from various Danish longitudinal registries and analyzed the data with conditional logistic regression. We noted that 1.17% suicide victims, compared with 0.79% matched controls, had a history of hospital contact for allergy and that a history of allergy predicted an increased risk for suicide completion; however, the effect was confined to allergy that led to inpatient treatment (IRR: 1.59, 95% CI: 1.41-1.80). The increased risk was attenuated somewhat but remained significant when adjusted for personal psychiatric history and socioeconomic status. Meanwhile, we observed a nonsignificantly stronger effect in women than in men, and a significant age difference with a stronger effect for individuals at high ages. Moreover, we detected a significant interaction between allergy and mood disorder - even an antagonism effect of the two exposures. Allergy increased suicide risk only in persons with no history of mood disorder, whereas it eliminated suicide risk in those with a history of mood disorder. The findings support a link between allergy and suicidality, with a possible mediating role of mood disorder. © 2010 John Wiley & Sons A/S.

Experimental demonstration of the fitness consequences of an introduced parasite of Darwin's finches.

PubMed

Koop, Jennifer A H; Huber, Sarah K; Laverty, Sean M; Clayton, Dale H

2011-05-11

Introduced parasites are a particular threat to small populations of hosts living on islands because extinction can occur before hosts have a chance to evolve effective defenses. An experimental approach in which parasite abundance is manipulated in the field can be the most informative means of assessing a parasite's impact on the host. The parasitic fly Philornis downsi, recently introduced to the Galápagos Islands, feeds on nestling Darwin's finches and other land birds. Several correlational studies, and one experimental study of mixed species over several years, reported that the flies reduce host fitness. Here we report the results of a larger scale experimental study of a single species at a single site over a single breeding season. We manipulated the abundance of flies in the nests of medium ground finches (Geospiza fortis) and quantified the impact of the parasites on nestling growth and fledging success. We used nylon nest liners to reduce the number of parasites in 24 nests, leaving another 24 nests as controls. A significant reduction in mean parasite abundance led to a significant increase in the number of nests that successfully fledged young. Nestlings in parasite-reduced nests also tended to be larger prior to fledging. Our results confirm that P. downsi has significant negative effects on the fitness of medium ground finches, and they may pose a serious threat to other species of Darwin's finches. These data can help in the design of management plans for controlling P. downsi in Darwin's finch breeding populations.

Reproductive biology and genetic diversity of the green turtle (Chelonia mydas) in Vamizi island, Mozambique.

PubMed

Anastácio, Rita; Santos, Camila; Lopes, Cardoso; Moreira, Helena; Souto, Luis; Ferrão, Jorge; Garnier, Julie; Pereira, Mário J

2014-01-01

Vamizi, an Island located in the Western Indian Ocean, is visited by a small and not fully characterized green turtle (Chelonia mydas (L.)) population. This population is threatened by natural hazards and several human activities, which are used to identify conservation priorities for marine turtles. It was our aim to contribute to the knowledge of marine turtles that nest in Vamizi, with respect to its regional management, and to an area that may possibly be included on the UNESCO World Heritage List due to its potential Outstanding Universal Value. Here, we evaluate the nesting parameters (incubation period, clutch size, hatching and emergence successes rates) and patterns over an 8-year (2003 - 2010) conservation program. We also present the results of genetic diversity based on the analysis of approximately an 850 pb fragment of the mitochondrial DNA control region. We found that Vamizi beaches host a small number of nesting females, approximately 52 per year, but these have shown a reduction in their length. High hatching success (88.5 ± SD 17.2%, N = 649), emergence success rates (84.5 ± SD 20.4%, N = 649) were observed, and genetic diversity (N = 135), with 11 haplotypes found (7 new). It was also observed, in the later years of this study, a reduction in the incubation period, a dislocation of the nesting peak activity and an increase in the number of flooded nests and an increase of the number of nests in areas with lower human activity. Some resilience and behavioral plasticity seems to occur regarding human territory occupancy and climate changes. However, regardless of the results, aspects like what seems to be the reduction of some cohorts, the number of flooded nests and the diminishing of the incubation period (East and South facing beaches), show that conservation efforts have to be improved.

Differentiation of Mycobacterium tuberculosis complex from non-tubercular mycobacteria by nested multiplex PCR targeting IS6110, MTP40 and 32kD alpha antigen encoding gene fragments.

PubMed

Sinha, Pallavi; Gupta, Anamika; Prakash, Pradyot; Anupurba, Shampa; Tripathi, Rajneesh; Srivastava, G N

2016-03-12

Control of the global burden of tuberculosis is obstructed due to lack of simple, rapid and cost effective diagnostic techniques that can be used in resource poor-settings. To facilitate the early diagnosis of TB directly from clinical specimens, we have standardized and validated the use of nested multiplex PCR, targeting gene fragments IS6110, MTP40 and 32kD α-antigen encoding genes specific for Mycobacterium tuberculosis complex and non-tubercular mycobacteria (NTM), in comparison to smear microscopy, solid culture and single step multiplex PCR. The results were evaluated in comparison to a composite reference standard (CRS) comprising of microbiological results (smear and culture), clinical, radiological and cytopathological findings, clinical treatment and response to anti-tubercular therapy. The nested multiplex PCR (nMPCR) assay was evaluated to test its utility in 600 (535 pulmonary and 65 extra-pulmonary specimens) clinically suspected TB cases. All specimens were processed for smear, culture, single step multiplex PCR and nested multiplex PCR testing. Out of 535 screened pulmonary and 65 extra-pulmonary specimens, 329 (61.5%) and 19 (29.2%) cases were culture positive for M. tuberculosis. Based on CRS, 450 patients had "clinical TB" (definitive-TB, probable-TB and possible-TB). Remaining 150 were confirmed "non-TB" cases. For culture, the sensitivity was low, 79.3% for pulmonary and 54.3% for extra-pulmonary cases. The sensitivity and specificity results for nMPCR test were evaluated taken composite reference standard as a gold standard. The sensitivity of the nMPCR assay was 97.1% for pulmonary and 91.4% for extra-pulmonary TB cases with specificity of 100% and 93.3% respectively. Nested multiplex PCR using three gene primers is a rapid, reliable and highly sensitive and specific diagnostic technique for the detection and differentiation of M. tuberculosis complex from NTM genome and will be useful in diagnosing paucibacillary samples. Nested multiplex PCR assay was found to be better than single step multiplex PCR for assessing the diagnosis of TB.

Decreased human leukocyte antigen A*02:01 frequency is associated with risk of glioma and existence of human cytomegalovirus: a case-control study in Northern China.

PubMed

Han, Sheng; Deng, Jian; Wang, Zixun; Liu, Huan; Cheng, Wen; Wu, Anhua

2017-10-01

Human leukocyte antigens (HLAs) play an important role in host defense against viral infection and tumorigenesis. Human cytomegalovirus (HCMV) has been linked to glioma development. This study investigated the relationship between HLA distribution, presence of HCMV, and glioma development in a Han Chinese population. The study population included 150 glioma patients and 150 tumor-free brain injury control subjects (control-A) matched according to geography, ethnicity, age, and gender. HLA allele frequency was compared between the two groups using peripheral blood samples by PCR sequence-based typing. These data were also compared with HLA frequencies obtained from a Northern Chinese Han population database (control-B). HCMV DNA was detected in the peripheral blood of glioma patients and control group-A by nested PCR. The expression of HCMV proteins IE1-72 and pp65 in tumor tissues was evaluated by immunohistochemistry. The frequency of HLA-A*02:01 was decreased in glioma patients as compared to control group-A and -B (P < 0.001 and P = 0.001, respectively). The age/sex-adjusted odds ratio for HLA-A*02:01 positivity vs. negativity was 0.392 (95% confidence interval 0.225-0.683). HCMV was more frequently detected in the peripheral blood and tumor tissue of HLA-A*02:01-negative glioma patients. HLA-A*02:01 and HCMV were not associated with overall survival. There is a correlation between decreased HLA-A*0201 allele frequency and glioma susceptibility.

Inhaled Corticosteroid Use in Chronic Obstructive Pulmonary Disease and Risk of Pneumonia: A Nested Case-Control Population-based Study in Lazio (Italy)-The OUTPUL Study.

PubMed

Cascini, Silvia; Kirchmayer, Ursula; Belleudi, Valeria; Bauleo, Lisa; Pistelli, Riccardo; Di Martino, Mirko; Formoso, Giulio; Davoli, Marina; Agabiti, Nera

2017-06-01

Inhaled corticosteroid (ICS) use in chronic obstructive pulmonary disease (COPD) patients is associated with a reduction of exacerbations and a potential risk of pneumonia. The objective was to determine if ICS use, with or without long-acting β 2 -agonist, increases pneumonia risk in COPD patients. A cohort study was performed using linked hospital and drug prescription databases in the Lazio region. Patients (45+) discharged with COPD in 2006-2009 were enrolled and followed from cohort entry until first admission for pneumonia, death or study end, 31 December, 2012. A nested case-control approach was used to estimate the rate ratio (RR) associated with current or past use of ICS adjusted for age, gender, number of exacerbations in the previous year and co-morbidities. Current users were defined as patients with their last ICS prescribed in the 60 days prior to the event. Past users were those with the last prescription between 61 and 365 days before the event. Current use was classified into three levels (high, medium, low) according to the medication possession ratio. Among the cohort of 19288 patients, 3141 had an event of pneumonia (incidence rate for current use 87/1000py, past use 32/1000py). After adjustment, patients with current use were 2.29 (95% confidence interval [CI]: 1.99-2.63) times more likely to be hospitalised for pneumonia with respect to no use; for past use RR was 1.23 (95% CI: 1.07-1.42). For older patients (80+), the rate was higher than that for younger patients. ICS use was associated with an excess risk of pneumonia. The effect was greatest for higher doses and in the very elderly.

Risk of non-fatal venous thromboembolism in women using oral contraceptives containing drospirenone compared with women using oral contraceptives containing levonorgestrel: case-control study using United States claims data

PubMed Central

Hernandez, Rohini K

2011-01-01

Objective To compare the risk of non-fatal venous thromboembolism in women receiving oral contraceptives containing drospirenone with that in women receiving oral contraceptives containing levonorgestrel. Design Nested case-control and cohort study. Setting The study was based on information from PharMetrics, a United States based company that collects information on claims paid by managed care plans. Participants The study encompassed all women aged 15 to 44 years who received an oral contraceptive containing either drospirenone or levonorgestrel after 1 January 2002. Cases were women with current use of a study oral contraceptive and a diagnosis of venous thromboembolism in the absence of identifiable clinical risk factors (idiopathic venous thromboembolism). Up to four controls were matched to each case by age and calendar time. Main outcome measures Odds ratios comparing the risk of non-fatal venous thromboembolism in users of the two contraceptives; incidence rates and rate ratios of non-fatal venous thromboembolism for users of each of the study contraceptives. Results 186 newly diagnosed, idiopathic cases of venous thromboembolism were identified in the study population and matched with 681 controls. In the case-control analysis, the conditional odds ratio for venous thromboembolism comparing use of oral contraceptives containing drospirenone with use of those containing levonorgestrel was 2.3 (95% confidence interval 1.6 to 3.2). The incidence rates for venous thromboembolism in the study population were 30.8 (95% confidence interval 25.6 to 36.8) per 100 000 woman years among users of oral contraceptives containing drospirenone and 12.5 (9.61 to 15.9) per 100 000 woman years among users of oral contraceptives containing levonorgestrel. The age adjusted incidence rate ratio for venous thromboembolism for current use of oral contraceptives containing drospirenone compared with those containing levonorgestrel was 2.8 (2.1 to 3.8). Conclusions The risk of non-fatal venous thromboembolism among users of oral contraceptives containing drospirenone seems to be around twice that of users of oral contraceptives containing levonorgestrel, after the effects of potential confounders and prescribing biases have been taken into account. PMID:21511805

Early diagnosis of typhoid fever by nested PCR for flagellin gene of Salmonella enterica serotype Typhi.

PubMed

Khan, S; Harish, B N; Menezes, G A; Acharya, N S; Parija, S C

2012-11-01

Typhoid fever caused by Salmonella Typhi continues to be a major health problem in spite of the use of antibiotics and the development of newer antibacterial drugs. Inability to make an early laboratory diagnosis and resort to empirical therapy, often lead to increased morbidity and mortality in cases of typhoid fever. This study was aimed to optimize a nested PCR for early diagnosis of typhoid fever and using it as a diagnostic tool in culture negative cases of suspected typhoid fever. Eighty patients with clinical diagnosis of typhoid fever and 40 controls were included in the study. The blood samples collected were subjected to culture, Widal and nested PCR targeting the flagellin gene of S. Typhi. The sensitivity of PCR on blood was found to be 100 per cent whereas the specificity was 76.9 per cent. The positive predictive value (PPV) of PCR was calculated to be 76.9 per cent with an accuracy of 86 per cent. None of the 40 control samples gave a positive PCR. Due to its high sensitivity and specificity nested PCR can be used as a useful tool to diagnose clinically suspected, culture negative cases of typhoid fever.

The potential value of sibling controls compared with population controls for association studies of lifestyle-related risk factors: an example from the Breast Cancer Family Registry.

PubMed

Milne, Roger L; John, Esther M; Knight, Julia A; Dite, Gillian S; Southey, Melissa C; Giles, Graham G; Apicella, Carmel; West, Dee W; Andrulis, Irene L; Whittemore, Alice S; Hopper, John L

2011-10-01

A previous Australian population-based breast cancer case-control study found indirect evidence that control participation, although high, was not random. We hypothesized that unaffected sisters may provide a more appropriate comparison group than unrelated population controls. Three population-based case-control-family studies of breast cancer in women of white European origin were carried out by the Australian, Ontario and Northern California sites of the Breast Cancer Family Registry. We compared risk factors between 3643 cases, 2444 of their unaffected sisters and 2877 population controls and conducted separate case-control analyses based on population and sister controls using unconditional multivariable logistic regression. Compared with sister controls, population controls were more highly educated, had an earlier age at menarche, fewer births, their first birth at a later age and their last birth more recently. The established breast cancer associations detected using sister controls, but not detected using population controls, were decreasing risk with each of later age at menarche, more births, younger age at first birth and greater time since last birth. Since participation of population controls might be unintentionally related to some risk factors, we hypothesize that sister controls could provide more valid relative risk estimates and be recruited at lower cost. Given declining study participation by population controls, this contention is highly relevant to epidemiologic research.

Barrett's Esophagus Methylation Profiles — EDRN Public Portal

Cancer.gov

We propose a nested case-control study of biomarkers in the setting of BE. By bringing together research institutions with large populations of patients with BE, we will perform a multi-center study of FISH and hypermethylation markers as possible prognostic factors in BE. The centers will select from their cohorts who have progressed to HGD or to adenocarcinoma of the esophagus ("progressors"), and who also donated samples prior to the development of cancer, when their histology was felt to be benign. These subjects will be compared to individuals who have been under endoscopic surveillance, but who have not progressed to HGD or EAC ("non-progressors"). Using this approach, we hope to identify promising markers for risk stratification in BE. We expect to be able to make successful application for a prospective study of markers identified in this case-control study.

Nest suitability, fine-scale population structure and male-mediated dispersal of a solitary ground nesting bee in an urban landscape.

PubMed

López-Uribe, Margarita M; Morreale, Stephen J; Santiago, Christine K; Danforth, Bryan N

2015-01-01

Bees are the primary pollinators of flowering plants in almost all ecosystems. Worldwide declines in bee populations have raised awareness about the importance of their ecological role in maintaining ecosystem functioning. The naturally strong philopatric behavior that some bee species show can be detrimental to population viability through increased probability of inbreeding. Furthermore, bee populations found in human-altered landscapes, such as urban areas, can experience lower levels of gene flow and effective population sizes, increasing potential for inbreeding depression in wild bee populations. In this study, we investigated the fine-scale population structure of the solitary bee Colletes inaequalis in an urbanized landscape. First, we developed a predictive spatial model to detect suitable nesting habitat for this ground nesting bee and to inform our field search for nests. We genotyped 18 microsatellites in 548 female individuals collected from nest aggregations throughout the study area. Genetic relatedness estimates revealed that genetic similarity among individuals was slightly greater within nest aggregations than among randomly chosen individuals. However, genetic structure among nest aggregations was low (Nei's GST = 0.011). Reconstruction of parental genotypes revealed greater genetic relatedness among females than among males within nest aggregations, suggesting male-mediated dispersal as a potentially important mechanism of population connectivity and inbreeding avoidance. Size of nesting patch was positively correlated with effective population size, but not with other estimators of genetic diversity. We detected a positive trend between geographic distance and genetic differentiation between nest aggregations. Our landscape genetic models suggest that increased urbanization is likely associated with higher levels of inbreeding. Overall, these findings emphasize the importance of density and distribution of suitable nesting patches for enhancing bee population abundance and connectivity in human dominated habitats and highlights the critical contribution of landscape genetic studies for enhanced conservation and management of native pollinators.

Nest Suitability, Fine-Scale Population Structure and Male-Mediated Dispersal of a Solitary Ground Nesting Bee in an Urban Landscape

PubMed Central

López-Uribe, Margarita M.; Morreale, Stephen J.; Santiago, Christine K.; Danforth, Bryan N.

2015-01-01

Bees are the primary pollinators of flowering plants in almost all ecosystems. Worldwide declines in bee populations have raised awareness about the importance of their ecological role in maintaining ecosystem functioning. The naturally strong philopatric behavior that some bee species show can be detrimental to population viability through increased probability of inbreeding. Furthermore, bee populations found in human-altered landscapes, such as urban areas, can experience lower levels of gene flow and effective population sizes, increasing potential for inbreeding depression in wild bee populations. In this study, we investigated the fine-scale population structure of the solitary bee Colletes inaequalis in an urbanized landscape. First, we developed a predictive spatial model to detect suitable nesting habitat for this ground nesting bee and to inform our field search for nests. We genotyped 18 microsatellites in 548 female individuals collected from nest aggregations throughout the study area. Genetic relatedness estimates revealed that genetic similarity among individuals was slightly greater within nest aggregations than among randomly chosen individuals. However, genetic structure among nest aggregations was low (Nei’s GST = 0.011). Reconstruction of parental genotypes revealed greater genetic relatedness among females than among males within nest aggregations, suggesting male-mediated dispersal as a potentially important mechanism of population connectivity and inbreeding avoidance. Size of nesting patch was positively correlated with effective population size, but not with other estimators of genetic diversity. We detected a positive trend between geographic distance and genetic differentiation between nest aggregations. Our landscape genetic models suggest that increased urbanization is likely associated with higher levels of inbreeding. Overall, these findings emphasize the importance of density and distribution of suitable nesting patches for enhancing bee population abundance and connectivity in human dominated habitats and highlights the critical contribution of landscape genetic studies for enhanced conservation and management of native pollinators. PMID:25950429

Predation and nutrients drive population declines in breeding waders.

PubMed

Møller, Anders Pape; Thorup, Ole; Laursen, Karsten

2018-04-20

Allee effects are defined as a decline in per capita fitness at low population density. We hypothesized that predation reduces population size of breeding waders and thereby the efficiency of predator deterrence, while total nitrogen through its effects on primary and secondary productivity increases population size. Therefore, nest predation could have negative consequences for population size because nest failure generally results in breeding dispersal and hence reduced local population density. To test these predictions, we recorded nest predation in five species of waders for 4,745 nests during 1987-2015 at the nature reserve Tipperne, Denmark. Predation rates were generally negatively related to conspecific and heterospecific population density, but positively related to overall population density of the entire wader community. Nest predation and population density were related to ground water level, management (grazing and mowing), and nutrients. High nest predation with a time lag of one year resulted in low overall breeding population density, while high nutrient levels resulted in higher population density. These two factors accounted for 86% of the variance in population size, presumably due to effects of nest predation on emigration, while nutrient levels increased the level of vegetation cover and the abundance of food in the surrounding brackish water. These findings are consistent with the hypothesis that predation may reduce population density through negative density dependence, while total nitrogen at adjacent shallow water may increase population size. Nest predation rates were reduced by high ground water level in March, grazing by cattle and mowing that affected access to and susceptibility of nests to predators. These effects can be managed to benefit breeding waders. © 2018 by the Ecological Society of America.

Agent-Based Simulation of Robotic Systems

DTIC Science & Technology

2003-06-01

of Birds....................................................................................11 3. Termites ...nearby flock-mates 3. Termites Another highly interesting self-organization example is encountered in termites : the periodic assembling of a nest by...a population (Kugler and Turvey, 1987). The nest building behavior of termites consists of several distinct phases of construction. In the first

Mediterranean diet and telomere length in Nurses' Health Study: population based cohort study.

PubMed

Crous-Bou, Marta; Fung, Teresa T; Prescott, Jennifer; Julin, Bettina; Du, Mengmeng; Sun, Qi; Rexrode, Kathryn M; Hu, Frank B; De Vivo, Immaculata

2014-12-02

To examine whether adherence to the Mediterranean diet was associated with longer telomere length, a biomarker of aging. Population based cohort study. Nurses' Health Study, an ongoing prospective cohort study of 121,700 nurses enrolled in 1976; in 1989-90 a subset of 32,825 women provided blood samples. 4676 disease-free women from nested case-control studies within the Nurses' Health Study with telomere length measured who also completed food frequency questionnaires. Association between relative telomere lengths in peripheral blood leukocytes measured by quantitative real time polymerase chain reaction and Alternate Mediterranean Diet score calculated from self reported dietary data. Greater adherence to the Mediterranean diet was associated with longer telomeres after adjustment for potential confounders. Least squares mean telomere length z scores were -0.038 (SE 0.035) for the lowest Mediterranean diet score groups and 0.072 (0.030) for the highest group (P for trend = 0.004). In this large study, greater adherence to the Mediterranean diet was associated with longer telomeres. These results further support the benefits of adherence to the Mediterranean diet for promoting health and longevity. © Crous-Bou et al 2014.

Preterm Birth and Prenatal Maternal Occupation: The Role of Hispanic Ethnicity and Nativity in a Population-Based Sample in Los Angeles, California

PubMed Central

Wilhelm, Michelle; Wang, Anthony; Ritz, Beate

2014-01-01

Objectives. We investigated preterm birth (PTB) in relation to maternal occupational exposure and whether effect measures were modified by Hispanic ethnicity and nativity in a population-based sample with high proportion of Hispanics. Methods. We used a case-control study (n = 2543) nested within a cohort of 58 316 births in Los Angeles County, California, in 2003. We categorized prenatal occupations using the US Census Occupation Codes and Classification System and developed a job exposure matrix. Odds ratios for PTB were estimated using logistic regression. Results. Odds ratios for PTB were increased for all women in health care practitioner and technical occupations, but the 95% confidence intervals included the null value; effects were more pronounced among Hispanics. We estimated elevated odds ratios for foreign-born Hispanic women in building and grounds cleaning and maintenance occupations. Shift work and physically demanding work affected births among US-born but not foreign-born Hispanics. Conclusions. Hispanic women are at particular risk for PTB related to adverse prenatal occupational exposure. Nativity may moderate these effects on PTB. Maternal occupational exposures likely contribute to ethnic disparities in PTB. PMID:24354840

Occupational exposure to asbestos and risk of cholangiocarcinoma: a population-based case–control study in four Nordic countries

PubMed Central

Farioli, Andrea; Straif, Kurt; Brandi, Giovanni; Curti, Stefania; Kjaerheim, Kristina; Martinsen, Jan Ivar; Sparen, Pär; Tryggvadottir, Laufey; Weiderpass, Elisabete; Biasco, Guido; Violante, Francesco Saverio; Mattioli, Stefano; Pukkala, Eero

2018-01-01

Objectives To assess the association between occupational exposure to asbestos and the risk of cholangiocarcinoma (CC). Methods We conducted a case–control study nested in the Nordic Occupational Cancer (NOCCA) cohort. We studied 1458 intrahepatic CC (ICC) and 3972 extrahepatic CC (ECC) cases occurring among subjects born in 1920 or later in Finland, Iceland, Norway and Sweden. Each case was individually matched by birth year, gender and country to five population controls. The cumulative exposure to asbestos (measured in fibres (f)/ml × years) was assessed by applying the NOCCA job-exposure matrix to data on occupations collected during national population censuses (conducted in 1960, 1970, 1980/81 and 1990). Odds ratios (OR) and 95% CI were estimated using conditional logistic regression models adjusted by printing industry work. Results We observed an increasing risk of ICC with cumulative exposure to asbestos: never exposed, OR 1.0 (reference category); 0.1–4.9 f/mL × years, OR 1.1 (95% CI 0.9 to 1.3); 5.0–9.9 f/mL × years, OR 1.3 (95% CI 0.9 to 2.1); 10.0–14.9 f/mL × years, OR 1.6 (95% CI 1.0 to 2.5); ≥15.0 f/mL × years, OR 1.7 (95% CI 1.1 to 2.6). We did not observe an association between cumulative asbestos exposure and ECC. Conclusions Our study provides evidence that exposure to asbestos might be a risk factor for ICC. Our findings also suggest that the association between ECC and asbestos is null or weaker than that observed for ICC. Further studies based on large industrial cohorts of asbestos workers and possibly accounting for personal characteristics and clinical history are needed. PMID:29133597

Vitamin D–binding protein and pancreatic cancer: a nested case-control study12345

PubMed Central

Piper, Marina R; Freedman, D Michal; Robien, Kim; Kopp, William; Rager, Helen; Horst, Ronald L

2015-01-01

Background: Vitamin D–binding protein (DBP) is the primary carrier of 25-hydroxyvitamin D [25(OH)D] in the circulation. One prospective study in male smokers found a protective association between DBP and pancreatic cancer, particularly among men with higher 25(OH)D concentrations. Objective: The objective was to examine the association between DBP and pancreatic cancer risk in an American population. Design: We conducted a nested case-control study in the Prostate, Lung, Colorectal, and Ovarian Cancer screening trial cohort of men and women aged 55–74 y at baseline. Between 1993 and 2010, 295 incident pancreatic adenocarcinoma cases were reported (follow-up to 15.1 y). Two controls (n = 590) were matched to each case by age, race, sex, and month of blood draw. We calculated smoking- and diabetes-adjusted ORs and 95% CIs with the use of conditional logistic regression. Results: DBP concentration was not significantly associated with pancreatic cancer overall [highest (≥7149.4 nmol/L) vs. lowest (<3670.4 nmol/L) quintile; OR: 1.75; 95% CI: 0.91, 3.37; P-trend = 0.25]. For serum 25(OH)D compared with the referent (50 to <75 nmol/L), individuals in the highest group had a significantly higher risk (≥100 nmol/L; OR: 3.23; 95% CI: 1.24, 8.44), whereas those in the lowest group had no significant association (<25 nmol/L; OR: 2.50; 95% CI: 0.92, 6.81). Further adjustment for DBP did not alter this association. Conclusion: Our results do not support the hypothesis that serum DBP or 25(OH)D plays a protective role in pancreatic cancer. This trial was registered at clinicaltrials.gov as NCT00339495. PMID:25904602

The effects of aminosalicylates or thiopurines on the risk of colorectal cancer in inflammatory bowel disease.

PubMed

Carrat, F; Seksik, P; Colombel, J-F; Peyrin-Biroulet, L; Beaugerie, L

2017-02-01

Whether aminosalicylates or thiopurines reduce the risk of colorectal cancer (CRC) in inflammatory bowel (IBD) disease is controversial. To assess simultaneously the chemopreventive effect of aminosalicylates or thiopurines in a case-control study nested in the CESAME observational cohort that enrolled consecutive patients with IBD between May 2004 and June 2005. Patients were followed up to December 2007. Study population comprised 144 case patients who developed CRC from the diagnosis of IBD (65 and 79 cases diagnosed, respectively, before and from 2004, starting year of the prospective observational period of CESAME) and 286 controls matched for gender, age, IBD subtype and year of diagnosis, and cumulative extent of colitis. Exposure to aminosalicylates or thiopurines was defined by an exposure to the treatment during the year of the diagnosis of cancer. The propensity of receiving 5-ASA and thiopurines was quantified by a composite score taking into account patient and IBD characteristics. The role of aminosalicylates or thiopurines was assessed by multivariate analysis. Propensity scores and the history of primary sclerosing cholangitis were entered into the multivariate model for adjustment. By multivariate analysis adjusted for propensity, a significant protective effect of exposure to drugs during the year of cancer was found for aminosalicylates (OR = 0.587, 95% CI: 0.367-0.937, P = 0.0257), but not for thiopurines (OR = 0.762, 95% CI: 0.432-1.343, P = 0.3468). In a case-control study nested in the CESAME cohort, a significant decrease in the risk of colorectal cancer in IBD was associated with exposure to aminosalicylates, not to thiopurines. © 2016 John Wiley & Sons Ltd.

Flexible social organization and high incidence of drifting in the sweat bee, Halictus scabiosae.

PubMed

Ulrich, Yuko; Perrin, Nicolas; Chapuisat, Michel

2009-04-01

The very diverse social systems of sweat bees make them interesting models to study social evolution. Here we focus on the dispersal behaviour and social organization of Halictus scabiosae, a common yet poorly known species of Europe. By combining field observations and genetic data, we show that females have multiple reproductive strategies, which generates a large diversity in the social structure of nests. A detailed microsatellite analysis of 60 nests revealed that 55% of the nests contained the offspring of a single female, whereas the rest had more complex social structures, with three clear cases of multiple females reproducing in the same nest and frequent occurrence of unrelated individuals. Drifting among nests was surprisingly common, as 16% of the 122 nests in the overall sample and 44% of the nests with complex social structure contained females that had genotypes consistent with being full-sisters of females sampled in other nests of the population. Drifters originated from nests with an above-average productivity and were unrelated to their nestmates, suggesting that drifting might be a strategy to avoid competition among related females. The sex-specific comparison of genetic differentiation indicated that dispersal was male-biased, which would reinforce local resource competition among females. The pattern of genetic differentiation among populations was consistent with a dynamic process of patch colonization and extinction, as expected from the unstable, anthropogenic habitat of this species. Overall, our data show that H. scabiosae varies greatly in dispersal behaviour and social organization. The surprisingly high frequency of drifters echoes recent findings in wasps and bees, calling for further investigation of the adaptive basis of drifting in the social insects.

Early life course risk factors for childhood obesity: the IDEFICS case-control study.

PubMed

Bammann, Karin; Peplies, Jenny; De Henauw, Stefaan; Hunsberger, Monica; Molnar, Denes; Moreno, Luis A; Tornaritis, Michael; Veidebaum, Toomas; Ahrens, Wolfgang; Siani, Alfonso

2014-01-01

The early life course is assumed to be a critical phase for childhood obesity; however the significance of single factors and their interplay is not well studied in childhood populations. The investigation of pre-, peri- and postpartum risk factors on the risk of obesity at age 2 to 9. A case-control study with 1,024 1:1-matched case-control pairs was nested in the baseline survey (09/2007-05/2008) of the IDEFICS study, a population-based intervention study on childhood obesity carried out in 8 European countries in pre- and primary school settings. Conditional logistic regression was used for identification of risk factors. For many of the investigated risk factors, we found a raw effect in our study. In multivariate models, we could establish an effect for gestational weight gain (adjusted OR = 1.02; 95%CI 1.00-1.04), smoking during pregnancy (adjusted OR = 1.48; 95%CI 1.08-2.01), Caesarian section (adjusted OR = 1.38; 95%CI 1.10-1.74), and breastfeeding 4 to 11 months (adjusted OR = 0.77; 95%CI 0.62-0.96). Birth weight was related to lean mass rather than to fat mass, the effect of smoking was found only in boys, but not in girls. After additional adjustment for parental BMI and parental educational status, only gestational weight gain remained statistically significant. Both, maternal as well as paternal BMI were the strongest risk factors in our study, and they confounded several of the investigated associations. Key risk factors of childhood obesity in our study are parental BMI and gestational weight gain; consequently prevention approaches should target not only children but also adults. The monitoring of gestational weight seems to be of particular importance for early prevention of childhood obesity.

Prior human polyomavirus and papillomavirus infection and incident lung cancer: a nested case-control study.

PubMed

Colombara, Danny V; Manhart, Lisa E; Carter, Joseph J; Hawes, Stephen E; Weiss, Noel S; Hughes, James P; Barnett, Matt J; Goodman, Gary E; Smith, Jennifer S; Qiao, You-Lin; Galloway, Denise A

2015-12-01

To test whether infection with select human polyomaviruses (HPyV) and human papillomaviruses (HPV) is associated with incident lung cancer. We performed a nested case-control study, testing serum from the carotene and retinol efficacy trial, conducted 1985-2005, for antibodies to Merkel cell (MCV), KI (KIV), and WU (WUV) HPyVs as well as to six high-risk and two low-risk HPV types. Incident lung cancer cases (n = 200) were frequency-matched with controls (n = 200) on age, enrollment and blood draw dates, intervention arm assignment, and the number of serum freeze/thaw cycles. Sera were tested using multiplex liquid bead microarray antibody assays. We used logistic regression to assess the association between HPyV and HPV antibodies and lung cancer. There was no evidence of a positive association between levels of MCV, KIV, or WUV antibodies and incident lung cancer (p corrected >0.10 for all trend tests; odds ratio (OR) range 0.72-1.09, p corrected >0.10 for all). There was also no evidence for a positive association between HPV 16 or 18 infection and incident lung cancer (p corrected ≥0.10 for all trend tests; OR range 0.25-2.54, p > 0.05 for all OR > 1), but the number of persons with serologic evidence of these infections was small. Prior infection with any of several types of HPyV or HPV was not associated with subsequent diagnosis of lung cancer. Infection with these viruses likely does not influence a person's risk of lung cancer in Western smoking populations.

Diet and alcohol as risk factors for rheumatoid arthritis: a nested case-control study.

PubMed

Sundström, B; Johansson, I; Rantapää-Dahlqvist, S

2015-03-01

The aim of this study was to investigate whether alcohol and diet, assessed as both macronutrients and dietary patterns, increased the risk of development of rheumatoid arthritis (RA) through a nested case-control design in the Västerbotten Intervention Program (VIP) cohort. Individuals in the VIP who had developed RA after the dietary survey were identified from medical records at the department of rheumatology at the University Hospital, Umeå (n = 386), and matched to 1,886 controls from the same database. Diet was assessed as food groups, as macronutrients and as scores of dietary patterns, namely the carbohydrate-restricted diet score, the Mediterranean diet score and the healthy diet indicator score. When analysing the dietary patterns, consumption of food groups and different macronutrients, a significant association was found in the highest tertile of carbohydrate-restricted diet among the cases with a subsequent anti-CCP-positive disease 1.40 (1.02-1.92), as well as in the highest tertile of protein consumption among smokers (OR = 1.80, 95% CI 1.09-2.95). However, after additional adjustment for sodium intake, these associations were no longer statistically significant. No association was observed between alcohol consumption and the risk of RA. To summarize, there were no significant associations between diet, or alcohol consumption, and the risk of development of RA within this cohort. The lack of any significant associations of alcohol consumption may be explained by a low consumption in the studied population overall or alternatively by methodological issues raised recently.

Radiation dose and subsequent risk for stomach cancer in long-term survivors of cervical cancer

PubMed Central

Kleinerman, Ruth A.; Smith, Susan A.; Holowaty, Eric; Hall, Per; Pukkala, Eero; Vaalavirta, Leila; Stovall, Marilyn; Weathers, Rita; Gilbert, Ethel; Aleman, Berthe M.P.; Kaijser, Magnus; Andersson, Michael; Storm, Hans; Joensuu, Heikki; Lynch, Charles F.; Dores, Graça M.; Travis, Lois B.; Morton, Lindsay M.; Curtis, Rochelle E.

2013-01-01

Purpose To assess the dose-response relationship for stomach cancer following radiotherapy for cervical cancer. Methods and Materials We conducted a nested, matched case-control study of 201 cases and 378 controls among 53,547 5-year survivors of cervical cancer diagnosed from 1943–1995, from five international, population-based cancer registries. We estimated individual radiation doses to the site of the stomach cancer for all cases and to corresponding sites for the matched controls (overall mean stomach tumor dose, 2.56 gray [Gy], range 0.03–46.1 and following parallel opposed pelvic fields, 1.63 Gy, range 0.12–6.3). Results Over 90% of women received radiotherapy, mostly with external beam therapy in combination with brachytherapy. Stomach cancer risk was non-significantly increased (odds ratios [ORs] 1.27–2.28) for women receiving between 0.5–4.9 Gy to the stomach cancer site and significantly increased at doses ≥5 Gy (OR=4.20, 95% confidence interval, 1.41–13.4, Ptrend=0.047) compared to non-irradiated women. A highly significant radiation dose-response relationship was evident when analyses were restricted to the 131 cases (251 controls) whose stomach cancer was located in the middle and lower portions of the stomach (Ptrend=0.003), whereas there was no indication of increasing risk with increasing dose for 30 cases (57 controls) whose cancer was located in the upper stomach (Ptrend=0.23). Conclusions Our findings showed for the first time a significant linear dose-response relationship for risk of stomach cancer in long-term survivors of cervical cancer. PMID:23707149

Island characteristics within wetlands influence waterbird nest success and abundance

USGS Publications Warehouse

Hartman, Christopher; Ackerman, Joshua T.; Herzog, Mark

2016-01-01

Coastal waterbird populations are threatened by habitat loss and degradation from urban and agricultural development and forecasted sea level rise associated with climate change. Remaining wetlands often must be managed to ensure that waterbird habitat needs, and other ecosystem functions, are met. For many waterbirds, the availability of island nesting habitat is important for conserving breeding populations. We used linear mixed models to investigate the influence of pond and island landscape characteristics on nest abundance and nest success of American avocets (Recurvirostra americana), black-necked stilts (Himantopus mexicanus), and Forster's terns (Sterna forsteri) in San Francisco Bay, California, USA, based on a 9-year dataset that included >9,000 nests. Nest abundance and nest success were greatest within ponds and on individual islands located either <1 km or >4 km from San Francisco Bay. Further, nest abundance was greater within ponds with relatively few islands, and on linear-shaped, highly elongated islands compared to more rounded islands. Nest success was greater on islands located away from the nearest surrounding pond levee. Compared to more rounded islands, linear islands contained more near-water habitat preferred by many nesting waterbirds. Islands located away from pond levees may provide greater protection from terrestrial egg and chick predators. Our results indicate that creating and maintaining a few, relatively small, highly elongated and narrow islands away from mainland levees, in as many wetland ponds as possible would be effective at providing waterbirds with preferred nesting habitat.

Serum carotenoid and tocopherol concentrations and risk of asthma in childhood: a nested case-control study.

PubMed

Hämäläinen, N; Nwaru, B I; Erlund, I; Takkinen, H-M; Ahonen, S; Toppari, J; Ilonen, J; Veijola, R; Knip, M; Kaila, M; Virtanen, S M

2017-03-01

The antioxidant hypothesis regarding the risk of asthma in childhood has resulted in inconsistent findings. Some data indicate that the role of antioxidants in childhood asthma risk may have a critical time window of effect, but only a well-designed longitudinal cohort study can clarify this hypothesis. To study the longitudinal associations between serum carotenoid and tocopherol concentrations during the first 4 years of life and asthma risk by the age of 5 years. Based on a case-control design nested within a Finnish birth cohort, 146 asthma cases were matched to 270 controls on birth time, sex, genetic risk, and birth place. Non-fasting blood samples were collected at the ages of 1, 1.5, 2, 3, and 4 years and serum carotenoids and tocopherols were analysed. Parents reported the presence and age at start of persistent doctor-diagnosed asthma in the child at the age of 5 years. Data analyses were conducted using generalized estimating equations. We did not find strong associations between serum carotenoids and tocopherols and the risk of asthma based on age-specific and longitudinal analyses. Both lower and higher quarters of α-carotene and γ-tocopherol increased the risk of asthma. The current findings do not support the suggestion that the increased prevalence of asthma may be a consequence of decreased intake of antioxidant nutrients. Moreover, we did not confirm any critical time window of impact of antioxidants on asthma risk. Replication of these findings in similar longitudinal settings will strengthen this evidence base. © 2017 John Wiley & Sons Ltd.

Major histocompatibility complex (MHC) class I and II alleles which confer susceptibility or protection in the Morphea in Adults and Children (MAC) cohort

PubMed Central

Jacobe, Heidi; Ahn, Chul; Arnett, Frank; Reveille, John D.

2014-01-01

Objective To determine human leukocyte antigen class I (HLA-class I) and II (HLA-class II) alleles associated with morphea (localized scleroderma) in the Morphea in Adults and Children (MAC) cohort by a nested case–control association study. Methods Morphea patients were included from MAC cohort and matched controls from the NIH/NIAMS Scleroderma Family Registry and DNA Repository and Division of Rheumatology at the University of Texas Health Science Center at Houston. HLA- Class II genotyping and SSCP typing was performed of HLA-A, -B, -C alleles. Associations between HLA-Class I and II alleles and morphea as well as its subphenotypes were determined. Results There were 211 cases available for HLA-class I typing with 726 matched controls and 158 cases available for HLA Class-II typing with 1108 matched controls. The strongest associations were found with DRB1*04:04 (OR 2.3, 95% CI 1.4–4.0 P=0.002) and HLA-B*37 conferred the highest OR among Class I alleles (3.3, 95% CI 1.6–6.9, P= 0.0016). Comparison with risk alleles in systemic sclerosis determined using the same methods and control population revealed one common allele (DRB*04:04). Conclusion Results of the present study demonstrate specific HLA Class I and II alleles are associated with morphea and likely generalized and linear subtypes. The associated morphea alleles are different than in scleroderma, implicating morphea is also immunogenetically distinct. Risk alleles in morphea are also associated with conditions such as rheumatoid arthritis (RA) and other autoimmune conditions. Population based studies indicate patients with RA have increased risk of morphea, implicating a common susceptibility allele. PMID:25223600

Assessing adherence in the CAPRISA 004 tenofovir gel HIV prevention trial: results of a nested case-control study.

PubMed

MacQueen, Kathleen M; Weaver, Mark A; van Loggerenberg, Francois; Succop, Stacey; Majola, Nelisle; Taylor, Doug; Karim, Quarraisha Abdool; Karim, Salim Abdool

2014-05-01

Adherence undeniably impacts product effectiveness in microbicide trials, but the connection has proven challenging to quantify using routinely collected behavioral data. We explored this relationship using a nested case-control study in the CAPRISA 004 Tenofovir (TFV) gel HIV prevention trial. Detailed 3-month recall data on sex events, condom and gel use were collected from 72 incident cases and 205 uninfected controls. We then assessed how the relationship between self-reported adherence and HIV acquisition differed between the TFV and placebo gel groups, an interaction effect that should exist if effectiveness increases with adherence. The CAPRISA 004 trial determined that randomization to TFV gel was associated with a significant reduction in risk of HIV acquisition. In our nested case-control study, however, we did not observe a meaningful decrease in the relative odds of infection-TFV versus placebo-as self-reported adherence increased. To the contrary, exploratory sub-group analysis of the case-control data identified greater evidence for a protective effect of TFV gel among participants reporting less than 80 % adherence to the protocol-defined regimen (odds ratio (OR) 0.30; 95 % CI 0.11-0.78) than among those reporting ≥ 80 % adherence (Odds Ratio 0.81; 95 % CI 0.34-1.92). The small number of cases may have inhibited our ability to detect the hypothesized interaction between adherence and effectiveness. Nonetheless, our results re-emphasize the challenges faced by investigators when adherence may be miss-measured, miss-reported, or confounded with the risk of HIV.

Acanthopria and Mimopriella parasitoid wasps (Diapriidae) attack Cyphomyrmex fungus-growing ants (Formicidae, Attini)

NASA Astrophysics Data System (ADS)

Fernández-Marín, Hermógenes; Zimmerman, Jess K.; Wcislo, William T.

2006-01-01

New World diapriine wasps are abundant and diverse, but the biology of most species is unknown. We provide the first description of the biology of diapriine wasps, Acanthopria spp. and Mimopriella sp., which attack the larvae of Cyphomyrmex fungus-growing ants. In Puerto Rico, the koinobiont parasitoids Acanthopria attack Cyphomyrmex minutus, while in Panama at least four morphospecies of Acanthopria and one of Mimopriella attack Cyphomyrmex rimosus. Of the total larvae per colony, 0 100% were parasitized, and 27 70% of the colonies per population were parasitized. Parasitism rate and colony size were negatively correlated for C. rimosus but not for C. minutus. Worker ants grasped at, bit, and in some cases, killed adult wasps that emerged in artificial nests or tried to enter natural nests. Parasitoid secondary sex ratios were female-biased for eclosing wasps, while field collections showed a male-biased sex ratio. Based on their abundance and success in attacking host ants, these minute wasps present excellent opportunities to explore how natural enemies impact ant colony demography and population biology.

Acrylamide and glycidamide hemoglobin adducts and epithelial ovarian cancer: a nested case-control study in non-smoking postmenopausal women from the EPIC cohort

PubMed Central

Obón-Santacana, Mireia; Lujan-Barroso, Leila; Travis, Ruth C.; Freisling, Heinz; Ferrari, Pietro; Severi, Gianluca; Baglietto, Laura; Boutron-Ruault, Marie-Christine; Fortner, Renée T.; Ose, Jennifer; Boeing, Heiner; Menéndez, Virginia; Sánchez-Cantalejo, Emilio; Chamosa, Saioa; Huerta Castaño, José María; Ardanaz, Eva; Khaw, Kay-Tee; Wareham, Nick; Merritt, Melissa A.; Gunter, Marc J.; Trichopoulou, Antonia; Papatesta, Eleni-Maria; Klinaki, Eleni; Saieva, Calogero; Tagliabue, Giovanna; Tumino, Rosario; Sacerdote, Carlotta; Mattiello, Amalia; Bueno-de-Mesquita, H.B.; Peeters, Petra H.; Onland-Moret, N. Charlotte; Idahl, Annika; Lundin, Eva; Weiderpass, Elisabete; Vesper, Hubert W.; Riboli, Elio; Duell, Eric J

2015-01-01

Background Acrylamide was classified as ‘probably carcinogenic to humans (group 2A)’ by the International Agency for Research on Cancer. Epithelial ovarian cancer (EOC) is the fourth cause of cancer mortality in women. Five epidemiological studies have evaluated the association between EOC risk and dietary acrylamide intake assessed using food frequency questionnaires, and one nested case-control study evaluated hemoglobin adducts of acrylamide (HbAA) and its metabolite glycidamide (HbGA) and EOC risk; the results of these studies were inconsistent. Methods A nested case-control study in non-smoking postmenopausal women (334 cases, 417 controls) was conducted within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Unconditional logistic regression models were used to estimate odds ratios (OR) and 95% confidence intervals (CI) for the association between HbAA, HbGA, HbAA+HbGA, and HbGA/HbAA and EOC and invasive serous EOC risk. Results No overall associations were observed between biomarkers of acrylamide exposure analyzed in quintiles and EOC risk; however, positive associations were observed between some middle quintiles of HbGA and HbAA+HbGA. Elevated but non-statistically significant ORs for serous EOC were observed for HbGA and HbAA+HbGA (ORQ5vsQ1:1.91, 95%CI:0.96-3.81 and ORQ5vsQ1:1.90, 95%CI:0.94-3.83, respectively); however, no linear dose-response trends were observed. Conclusion This EPIC nested case-control study failed to observe a clear association between biomarkers of acrylamide exposure and the risk of EOC or invasive serous EOC. Impact It is unlikely that dietary acrylamide exposure increases ovarian cancer risk; however, additional studies with larger sample size should be performed to exclude any possible association with EOC risk. PMID:26376083

Synchrony of Piping Plover breeding populations in the U.S. Northern Great Plains

USGS Publications Warehouse

Roche, Erin A.; Shaffer, Terry L.; Dovichin, Colin M.; Sherfy, Mark H.; Anteau, Michael J.; Wiltermuth, Mark T.

2016-01-01

Local populations that fluctuate synchronously are at a greater risk of extinction than those that do not. The closer the geographic proximity of populations, the more prone they are to synchronizing. Shorebird species select habitat broadly, and many breed across regions with diverse nesting habitat types. Under these conditions, nearby populations may experience conditions sufficiently different to prevent population synchrony, despite dispersal. In the U.S. Northern Great Plains, the Piping Plover (Charadrius melodus), federally listed as Threatened, is a migratory shorebird species that nests on the shorelines of rivers, reservoirs, and alkaline lakes. We assessed the degree to which local plover breeding population abundances were correlated (population synchrony), changed over time (population stability), and were influenced by environmental factors such as available habitat, precipitation, and within-season reservoir level rise. We found that the abundances of breeding populations nesting in riverine and reservoir habitats were the most synchronous, while populations nesting in alkaline lake habitats exhibited the greatest stability. Changes in local breeding population abundances were not explained by a single factor across habitat types. However, the abundances of local populations nesting in alkaline lake and river shoreline habitats were positively correlated with changes in nesting habitat availability. Our results suggest that dispersal among populations nesting in either river or reservoir and alkaline lake shoreline habitat may have an overall stabilizing effect on the persistence of the Great Plains Piping Plover metapopulation.

Breeding of White-tailed Tropicbirds (Phaethon lepturus) in the western South Atlantic.

PubMed

Leal, G R; Serafini, P P; Simão-Neto, I; Ladle, R J; Efe, M A

2016-04-19

Basic information on natural history is crucial for assessing the viability of populations, but is often lacking for many species of conservation concern. One such species is the White-tailed Tropicbird, Phaethon lepturus (Mathews, 1915). Here, we address this shortfall by providing detailed information on reproductive biology, distribution and threats on the Fernando de Noronha archipelago, Brazil - the largest colony of P. lepturus in the South Atlantic. We assessed reproduction from August 2011 to January 2012 by monitoring tropicbird nests and their contents. A population estimate was obtained through a combination of active searches for nests and by census at sea between 2010 and 2012. Breeding success was calculated by traditional methods. The growth curve of chicks and life table were also calculated. Additional information on nest and mate fidelity and on age of breeding birds was obtained from the banded birds. Our results indicate that the unusual nest form (limestone pinnacles) and predation by crabs may be responsible for the observed patterns of hatching and fledging success. Although the Fernando de Noronha population appears to be stable (at between 100-300 birds), a long term monitoring program would be desirable to assess fluctuations in this globally important population. Conservation strategies should focus on controlling predation by land crabs and tegu lizards.

Anatomy of a bottleneck: diagnosing factors limiting population growth in the Puerto Rican parrot

USGS Publications Warehouse

Beissenger, S.R.; Wunderle, J.M.; Meyers, J.M.; Saether, B.-E.; Engen, S.

2008-01-01

The relative importance of genetic, demographic, environmental, and catastrophic processes that maintain population bottlenecks has received little consideration. We evaluate the role of these factors in maintaining the Puerto Rican Parrot (Amazona vittata) in a prolonged bottleneck from 1973 through 2000 despite intensive conservation efforts. We first conduct a risk analysis, then examine evidence for the importance of specific processes maintaining the bottleneck using the multiple competing hypotheses approach, and finally integrate these results through a sensitivity analysis of a demographic model using life-stage simulation analysis (LSA) to determine the relative importance of genetic, demographic, environmental, and catastrophic processes on population growth. Annual population growth has been slow and variable (1.0 6 5.2 parrots per year, or an average k?1.05 6 0.19) from 16 parrots (1973) to a high of 40-42 birds (1997-1998). A risk analysis based on population prediction intervals (PPI) indicates great risk and large uncertainty, with a range of 22?83 birds in the 90% PPI only five years into the future. Four primary factors (reduced hatching success due to inbreeding, failure of adults to nest, nest failure due to nongenetic causes, and reduced survival of adults and juveniles) were responsible for maintaining the bottleneck. Egghatchability rates were low (70.6% per egg and 76.8% per pair), and hatchability increased after mate changes, suggesting inbreeding effects. Only an average of 34% of the population nested annually, which was well below the percentage of adults that should have reached an age of first breeding (41-56%). This chronic failure to nest appears to have been caused primarily by environmental and/or behavioral factors, and not by nest-site scarcity or a skewed sex ratio. Nest failure rates from nongenetic causes (i.e., predation, parasitism, and wet cavities) were low (29%) due to active management (protecting nests and fostering captive young into wild nests), diminishing the importance of nest failure as a limiting factor. Annual survival has been periodically reduced by catastrophes (hurricanes), which have greatly constrained population growth, but survival rates were high under non-catastrophic conditions. Although the importance of factors maintaining the Puerto Rican Parrot bottleneck varied throughout the 30-year period of study, we determined their long-term influence using LSA simulations to correlate variation in demographic rates with variation in population growth (k). The bottleneck appears to have been maintained primarily by periodic catastrophes (hurricanes) that reduced adult survival, and secondarily by environmental and/or behavioral factors that resulted in a failure of many adults to nest. The influence of inbreeding through reduced hatching success played a much less significant role, even when additional effects of inbreeding on the production and mortality of young were incorporated into the LSA. Management actions needed to speed recovery include (1) continued nest guarding to minimize the effects of nest failure due to nongenetic causes; (2) creating a second population at another location on the island --a process that was recently initiated--to reduce the chance that hurricane strikes will cause extinction; and (3) determining the causes of the low percentage of breeders in the population and ameliorating them, which would have a large impact on population growth.

Fitness consequences of nest desertion in an endangered host, the least Bell's vireo

USGS Publications Warehouse

Kus, Barbara E.

2002-01-01

Recent analyses of the impact of cowbird parasitism on host productivity suggest that while parasitism reduces productivity on a per-nest basis, the ability of pairs to desert parasitized nests and renest allows them to achieve productivity comparable to that of unparasitized pairs. This has implications for the management of several endangered species that are highly vulnerable to parasitism and consequently the target of cowbird control programs. I calculated seasonal nesting effort (number of nests per pair) and productivity of 568 pairs of Least Bell's Vireos (Vireo bellii pusillus) monitored over 11 years at the San Luis Rey River in San Diego County, California (where cowbird trapping has reduced, but not eliminated, parasitism), assigning pairs to one of three groups: (1) deserters, (2) rescued (parasitized pairs with nests “rescued” from probable failure by the removal of cowbird eggs), and (3) unparasitized. Parasitized pairs attempted significantly more nests per season than did unparasitized pairs, with deserters producing more nests than rescued pairs. However, productivity of deserting pairs was significantly lower than that of both rescued and unparasitized pairs, largely because subsequent nests of deserting pairs were also parasitized. Seasonal productivity of rescued and unparasitized pairs was comparable, indicating that in this species, reduction of cowbird impacts through nest manipulation to remove cowbird eggs is effective. Desertion by Least Bell's Vireos does not appear to be an adequate natural defense against parasitism, suggesting the need for continued cowbird control while vireo populations are re-established.

Specific and Non-specific Clinical Presentations in the Year Before the Diagnosis of Childhood Leukaemia.

PubMed

Yang, TienYu Owen; Liu, Yen-Lin; Huang, Wan-Ting; Chen, Mei-Huei; Chen, Pau-Chung

2016-08-01

Clinical presentations of childhood leukaemia have been reported in case-only studies. The timing when these presentations start to occur prior to diagnosis is less clear. In this nested case-control study, 1,025 and 334 children with lymphoid and myeloid leukaemia, respectively, were matched (1:30) to population-based controls by sex, region and year of birth. An index date was assigned for each control when the matched case was diagnosed. Healthcare access records of cases and controls in the year before the index date were extracted. Children with lymphoid leukaemia started to visit doctors more often at least 2 months before leukaemia diagnosis (P < 0.05). Various presentations were recorded in these visits: rates of haematological presentations, musculoskeletal presentations, and injuries started to increase significantly at least 3 months before diagnosis; rates of respiratory, gastrointestinal and urinary tract presentations did not increase significantly until the last month. The findings for myeloid lymphoma were less clear, but children appeared to visit doctors more often at least 4 months before diagnosis, and the rate of haematological presentations also started to increase at least 4 months before leukaemia diagnosis. Although haematological presentations were most strongly associated with undiagnosed leukaemia (odds ratio > 290 in the last month), the majority (>96%) of children with haematological presentations did not have leukaemia if they had not been diagnosed in their first visit. We described a clinical picture in the year before leukaemia diagnosis. These findings revealed ongoing difficulties in early diagnosis of childhood leukaemia in healthcare settings. © 2016 Wiley Periodicals, Inc.

Assessing health and rehabilitation needs of people with disabilities in Cameroon and India.

PubMed

Mactaggart, Islay; Kuper, Hannah; Murthy, G V S; Sagar, Jayanthi; Oye, Joseph; Polack, Sarah

2016-09-01

To assess the association between disability and serious health problems, and the access and uptake of health and rehabilitation services in Cameroon and India. We undertook a population-based case-control study, nested within a survey in Fundong Health District, North West Cameroon (August-October 2013) and in Mahbubnagar District, Telangana State, India (February-April 2014). Disability was defined as the presence of self-reported difficulties in functioning or clinical impairments. One control without disability was selected per case, matched by age, gender and cluster. Information was collected using structured questionnaires on: socioeconomic status, health, access to health services and rehabilitation. Cases with disability were significantly more likely to report a serious health problem in the last year compared to controls in both India (OR = 3.2, 95% CI 2.1-4.8) and Cameroon (OR = 1.9, 1.4-2.7). The vast majority of people sought care when seriously ill, and this did not vary between cases and controls. Awareness and use of rehabilitation services was extremely low in both Cameroon and India. Further focus is needed to improve awareness of rehabilitation services among people with disabilities in India and Cameroon to ensure that their rights are fulfilled and to achieve the goal of Universal Health Coverage. Implications for Rehabilitation People with and without disabilities equally seek health care in India and Cameroon. However, people with disabilities experience more frequent serious health problems than people without. Extremely few people with disabilities were aware of rehabilitation services despite their existence in the study settings.

An aerial sightability model for estimating ferruginous hawk population size

USGS Publications Warehouse

Ayers, L.W.; Anderson, S.H.

1999-01-01

Most raptor aerial survey projects have focused on numeric description of visibility bias without identifying the contributing factors or developing predictive models to account for imperfect detection rates. Our goal was to develop a sightability model for nesting ferruginous hawks (Buteo regalis) that could account for nests missed during aerial surveys and provide more accurate population estimates. Eighteen observers, all unfamiliar with nest locations in a known population, searched for nests within 300 m of flight transects via a Maule fixed-wing aircraft. Flight variables tested for their influence on nest-detection rates included aircraft speed, height, direction of travel, time of day, light condition, distance to nest, and observer experience level. Nest variables included status (active vs. inactive), condition (i.e., excellent, good, fair, poor, bad), substrate type, topography, and tree density. A multiple logistic regression model identified nest substrate type, distance to nest, and observer experience level as significant predictors of detection rates (P < 0.05). The overall model was significant (??26 = 124.4, P < 0.001, n = 255 nest observations), and the correct classification rate was 78.4%. During 2 validation surveys, observers saw 23.7% (14/59) and 36.5% (23/63) of the actual population. Sightability model predictions, with 90% confidence intervals, captured the true population in both tests. Our results indicate standardized aerial surveys, when used in conjunction with the predictive sightability model, can provide unbiased population estimates for nesting ferruginous hawks.

Sibship size, birth order and risk of nasopharyngeal carcinoma and infectious mononucleosis: a nationwide study in Sweden.

PubMed

Liu, Zhiwei; Fang, Fang; Chang, Ellen T; Adami, Hans-Olov; Ye, Weimin

2016-06-01

The aetiology of nasopharyngeal carcinoma (NPC) remains enigmatic in endemic and non-endemic areas. Early-life infection with Epstein-Barr virus (EBV) may predispose to NPC development, whereas delayed primary infection with EBV may cause infectious mononucleosis (IM). We used Swedish population and health registers to investigate whether potential indicators of early EBV infection, such as birth order, sibship size, maternal age and paternal age, are related to the subsequent risks for NPC and IM. We conducted two nested case-control studies, one for each health outcome, based on 251 NPC case patients, 11 314 IM case patients and five population control subjects per case matched by birth year and sex. We used conditional logistic regression modelling to estimate odds ratios (ORs) and their 95% confidence intervals (CIs) for NPC and IM. The multivariate-adjusted ORs of developing NPC increased with number of siblings; the ORs associated with having one, two and three or more siblings, compared with none, were 1.59 (95% CI = 0.97, 2.62), 1.94 (95% CI = 1.17, 3.22), and 2.03 (95% CI = 1.23, 3.35), respectively (Ptrend = 0.006). This increased risk of NPC was explained mainly by having older rather than younger siblings. In contrast, lower risks of IM were observed among individuals with an increasing number of older siblings, younger siblings and total siblings. Early-life social environment, possibly related to EBV infection, contributes to NPC pathogenesis in non-endemic areas. This hypothesis is further supported by the clearly contrasting findings between NPC and IM. © The Author 2015; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.

Prevalence of non-organ-specific autoantibodies and chronic liver disease in the general population: a nested case-control study of the Dionysos cohort

PubMed Central

Lenzi, M; Bellentani, S; Saccoccio, G; Muratori, P; Masutti, F; Muratori, L; Cassani, F; Bianchi, F; Tiribelli, C

1999-01-01

BACKGROUND—Several retrospective and prospective studies report an increased prevalence of non-organ-specific autoantibodies (NOSAs) in patients with hepatitis C virus (HCV) related chronic liver disease (CLD). Some of the data so far available are controversial and the true prevalence of NOSAs in the general population is still not known.
AIM—To explore the prevalence of NOSAs, their relation to different HCV genotypes, and the presence and severity of CLD in the general population of Northern Italy.
PATIENTS—All 226 anti-HCV positive and 87 hepatitis B surface antigen (HBsAg) positive patients of the Dionysos cohort study were analysed and compared with sex and age matched cases (226) negative for both anti-HCV antibody and HBsAg selected from the same cohort.
METHODS—Sera tested for the presence of NOSAs (anti-nuclear antibody (ANA), anti-smooth muscle antibody (SMA), and anti-liver/kidney microsomes type 1 antibody (LKM1)) were screened by indirect immunofluorescence at a 1:40 serum dilution. HCV RNA and HCV genotypes were also determined by nested polymerase chain reaction (PCR) of the 5' non-coding region and by PCR amplification of the core region with type specific primers.
RESULTS—The overall prevalence of NOSA reactivity was significantly higher in anti-HCV positive subjects than in both normal and pathological controls (25% v 6% and 7% respectively, p<0.05). ANA, SMA, and LKM1 occurred in 16, 10, and 1.3% of cases respectively. No specific association between NOSAs and a specific HCV genotype was found. NOSAs were found more often associated with more than one genotype (35.7%) and with untypable genotypes (34.6%), although the association was not statistically significant. NOSAs were associated with HCV RNA and CLD but not with the presence of cirrhosis and/or hepatocellular carcinoma. On univariate analysis, NOSA reactivity was independently associated with abnormal alanine aminotransferase (p<0.01) and γ-glutamyltranspeptidase levels (p<0.05). The risk for the presence of NOSAs was 5.1 times higher in anti-HCV subjects than in controls.
CONCLUSIONS—In the general population the prevalence of NOSAs is higher in anti-HCV positive subjects than in normal or disease controls. Moreover NOSAs are associated with CLD and with a more active disease in terms of alanine aminotransferase activity.


Keywords: non-organ-specific autoantibodies; hepatitis C virus genotypes; chronic liver disease; cohort study; prevalence PMID:10446115

Naturally Occurring Mutations in Large Surface Genes Related to Occult Infection of Hepatitis B Virus Genotype C

PubMed Central

Kim, Hong; Lee, Seoung-Ae; Kim, Dong-Won; Lee, Sueng-Hyun; Kim, Bum-Joon

2013-01-01

Molecular mechanisms related to occult hepatitis B virus (HBV) infection, particularly those based on genotype C infection, have rarely been determined thus far in the ongoing efforts to determine infection mechanisms. Therefore, we aim to elucidate the mutation patterns in the surface open reading frame (S ORF) underlying occult infections of HBV genotype C in the present study. Nested PCRs were applied to 624 HBV surface antigen (HBsAg) negative Korean subjects. Cloning and sequencing of the S ORF gene was applied to 41 occult cases and 40 control chronic carriers. Forty-one (6.6%) of the 624 Korean adults with HBsAg-negative serostatus were found to be positive for DNA according to nested PCR tests. Mutation frequencies in the three regions labeled here as preS1, preS2, and S were significantly higher in the occult subjects compared to the carriers in all cases. A total of two types of deletions, preS1 deletions in the start codon and preS2 deletions as well as nine types of point mutations were significantly implicated in the occult infection cases. Mutations within the “a” determinant region in HBsAg were found more frequently in the occult subjects than in the carriers. Mutations leading to premature termination of S ORF were found in 16 occult subjects (39.0%) but only in one subject from among the carriers (2.5%). In conclusion, our data suggest that preS deletions, the premature termination of S ORF, and “a” determinant mutations are associated with occult infections of HBV genotype C among a HBsAg-negative population. The novel mutation patterns related to occult infection introduced in the present study can help to broaden our understanding of HBV occult infections. PMID:23349904

Effects of illegal harvest of eggs on the population decline of leatherback turtles in Las Baulas Marine National Park, Costa Rica.

PubMed

Tomillo, Pilar Santidrián; Saba, Vincent S; Piedra, Rotney; Paladino, Frank V; Spotila, James R

2008-10-01

Within 19 years the nesting population of leatherback turtles (Dermochelys coriacea) at Parque Nacional Marino Las Baulas declined from 1500 turtles nesting per year to about 100. We analyzed the effects of fishery bycatch and illegal harvesting (poaching) of eggs on this population. We modeled the population response to different levels of egg harvest (90, 75, 50, and 25%) and the effect of eradicating poaching at different times during the population decline. We compared effects of 90% poaching with those of 20% adult mortality because both of these processes were present in the population at Las Baulas. There was a stepwise decline in number of nesting turtles at all levels of egg harvest. Extirpation times for different levels of poaching ranged from 45 to 282 years. The nesting population declined more slowly and survived longer with 20% adult mortality (146 years) than it did with 90% poaching (45 years). Time that elapsed until poaching stopped determined the average population size at which the population stabilized, ranging from 90 to 420 nesting turtles. Our model predicted that saving clutches lost naturally would restore the population when adult mortality rates were low and would contribute more to population recovery when there were short remigration intervals between nesting seasons and a large proportion of natural loss of clutches. Because the model indicated that poaching was the most important cause of the leatherback decline at Las Baulas, protecting nests on the beach and protecting the beach from development are critical for survival of this population. Nevertheless, the model predicted that current high mortality rates of adults will prevent population recovery. Therefore, protection of the beach habitat and nests must be continued and fishery bycatch must be reduced to save this population.

Similarity between generic and brand-name antihypertensive drugs for primary prevention of cardiovascular disease: evidence from a large population-based study.

PubMed

Corrao, Giovanni; Soranna, Davide; Merlino, Luca; Mancia, Giuseppe

2014-10-01

Although generic and earlier brand-name counterparts are bioequivalent, their equivalence in preventing relevant clinical outcomes is of concern. To compare effectiveness of generic and brand-name antihypertensive drugs for preventing the onset of cardiovascular (CV) outcomes. A population-based, nested case-control study was carried out by including the cohort of 78 520 patients from Lombardy (Italy) aged 18 years or older who were newly treated with antihypertensive drugs during 2005. Cases were the 2206 patients who experienced a hospitalization for CV disease from initial prescription until 2011. One control for each case was randomly selected from the same cohort that generated cases. Logistic regression was used to model the CV risk associated with starting on and/or continuing with generic or brand-name agents. There was no evidence that patients who started on generics experienced different CV risk than those on brand-name product (OR 0·86; 95% CI 0·63-1·17). Patients at whom generics were main dispensed had not significantly difference in CV outcomes than those mainly on brand-name agents (OR 1·19; 95% CI 0·86-1·63). Compared with patients who kept initial brand-name therapy, those who experienced brand-to-generic or generic-to-brand switches, and those always on generics, did not show differential CV risks, being the corresponding ORs (and 95% CIs), 1·18 (0·96-1·47), 0·87 (0·63-1·21) and 1·08 (0·80-1·46). Our findings do not support the notion that brand-name antihypertensive agents are superior to generics for preventing CV outcomes in the real-world clinical practice. © 2014 Stichting European Society for Clinical Investigation Journal Foundation.

Adverse events with intravitreal injection of vascular endothelial growth factor inhibitors: nested case-control study

PubMed Central

Gill, Sudeep S; Bronskill, Susan E; Paterson, J Michael; Whitehead, Marlo

2012-01-01

Objective To assess the risk of systemic adverse events associated with intravitreal injections of vascular endothelial growth factor inhibiting drugs. Design Population based nested case-control study. Setting Ontario, Canada. Participants 91 378 older adults with a history of physician diagnosed retinal disease identified between 1 April 2006 and 31 March 2011. Cases were 1477 patients admitted to hospital for ischaemic stroke, 2229 admitted for an acute myocardial infarction, 1059 admitted or assessed in an emergency department for venous thromboembolism, and 2623 admitted for congestive heart failure. Event-free controls (at a ratio of 5:1) were matched to cases on the basis of year of birth, sex, history of the outcome in the previous 5 years, and diabetes. Main exposure measure Exposure to vascular endothelial growth factor inhibiting drugs identified within 180 days before the index date. Results After adjustment for potential confounders, participants who had ischaemic stroke, acute myocardial infarction, congestive heart failure, or venous thromboembolism were not more likely than control participants to have been exposed to either bevacizumab (adjusted odds ratios of 0.95 (95% confidence interval 0.68 to 1.34) for ischaemic stroke, 1.04 (0.77 to 1.39) for acute myocardial infarction, 0.81 (0.49 to 1.34) for venous thromboembolism, and 1.21 (0.91 to 1.62) for congestive heart failure) or ranibizumab (adjusted odds ratios 0.87 (0.68 to 1.10) for ischaemic stroke, 0.90 (0.72 to 1.11) for acute myocardial infarction, 0.88 (0.67 to 1.16) for venous thromboembolism, and 0.87 (0.70 to 1.07) for congestive heart failure). Similarly, a secondary analysis of exclusive users of bevacizumab or ranibizumab showed no differences in risk between the two drugs (adjusted odds ratios for bevacizumab relative to ranibizumab of 1.03 (0.67 to 1.60) for ischaemic stroke, 1.23 (0.85 to 1.77) for acute myocardial infarction, 0.92 (0.51 to 1.69) for venous thromboembolism, and 1.35 (0.93 to 1.95) for congestive heart failure). These findings were consistent for all but one outcome in subgroup analyses. Conclusions Intravitreal injections of bevacizumab and ranibizumab were not associated with significant risks of ischaemic stroke, acute myocardial infarction, congestive heart failure, or venous thromboembolism. PMID:22763393

Occupational Exposure to Electric Shocks and Magnetic Fields and Amyotrophic Lateral Sclerosis in Sweden.

PubMed

Fischer, Heidi; Kheifets, Leeka; Huss, Anke; Peters, Tracy L; Vermeulen, Roel; Ye, Weimin; Fang, Fang; Wiebert, Pernilla; Vergara, Ximena P; Feychting, Maria

2015-11-01

Amyotrophic lateral sclerosis (ALS) has been consistently related to "electric occupations," but associations with magnetic field levels were generally weaker than those with electrical occupations. Exposure to electric shock has been suggested as a possible explanation. Furthermore, studies were generally based on mortality or prevalence of ALS, and studies often had limited statistical power. Using two electric shock and three magnetic field job-exposure matrices, we evaluated the relationship of occupational magnetic fields, electric shocks, electric occupations, and incident ALS in a large population-based nested case-control study in Sweden. Subanalyses, specified a priori, were performed for subjects by gender and by age (less than and more than 65 years). Overall, we did not observe any associations between occupational magnetic field or electric shock exposure and ALS. For individuals less than 65 years old, high electric shock exposure was associated with an odds ratio (OR) of 1.22 (95% confidence interval [CI] = 1.03, 1.43). The corresponding result for the age group 65 years or older was OR = 0.92 (95% CI = 0.81, 1.05). Results were similar regardless which job exposure matrices, exposure definitions, or cutpoints were used. For electric occupations, ORs were close to unity, regardless of age. For welders, no association was observed overall, although for welders <65 years the OR was 1.52 (95% CI = 1.05, 2.21). In this very large population-based study based on incident ALS case subjects, we did not confirm previous observations of higher risk of ALS in electrical occupations, and provided only weak support for associations between electric shocks and ALS.

Sandhill crane abundance and nesting ecology at Grays Lake, Idaho

USGS Publications Warehouse

Austin, J.E.; Henry, A.R.; Ball, I.J.

2007-01-01

We examined population size and factors influencing nest survival of greater sandhill cranes (Grus canadensis tabida) at Grays Lake National Wildlife Refuge, Idaho, USA, during 1997-2000. Average local population of cranes from late April to early May, 1998-2000, was 735 cranes, 34% higher than that reported for May 1970-1971. We estimated 228 (SE = 30) nests in the basin core (excluding renests), 14% higher than a 1971 estimate. Apparent nest success in our study (x?? = 60%, n = 519 nests) was lower than reported for Grays Lake 30-50 years earlier. Daily survival rates (DSRs) of all nests averaged 0.9707 (41.2%). The best model explaining nest survival included year and water depth and their interaction. Nest survival was highest (DSR = 0.9827) in 1998 compared with other years (0.9698-0.9707). Nest survival changed little relative to water depth in 1998, when flooding was extensive and alternative prey (microtines) irrupted, but declined markedly with lower water levels in 2000, the driest year studied. Hypotheses relating nest survival to vegetation height, land use (idle, summer grazing, fall grazing), and date were not supported. In a before-after-control-impact design using 12 experimental fields, nest survival differed among years but not among management treatments (idle, fall graze, fall burn, and summer-graze-idle rotation), nor was there an interaction between year and treatments. However, DSRs in fall-burn fields declined from 0.9781 in 1997-1998 to 0.9503 in 1999-2000 (posttreatment). Changes in the predator community have likely contributed to declines in nest success since the 1950s and 1970s. Our results did not support earlier concerns about effects of habitat management practices on crane productivity. Nest survival could best be enhanced by managing spring water levels. Managers should continue censuses during late April to evaluate long-term relationships to habitat conditions and management.

Off-road vehicles affect nesting behaviour and reproductive success of American Oystercatchers Haematopus palliatus

USGS Publications Warehouse

Borneman, Tracy E.; Rose, Eli T.; Simons, Theodore R.

2016-01-01

As human populations and associated development increase, interactions between humans and wildlife are occurring with greater frequency. The effects of these interactions, particularly on species whose populations are declining, are of great interest to ecologists, conservationists, land managers and natural resource policy-makers. The American Oystercatcher Haematopus palliatus, a species of conservation concern in the USA, nests on coastal beaches subject to various forms of anthropogenic disturbance, including aircraft overflights, off-road vehicles and pedestrians. This study assessed the effects of these human disturbances on the incubation behaviour and reproductive success of nesting American Oystercatchers at Cape Lookout National Seashore, on the Atlantic coast of the USA. We expanded on-going monitoring of Oystercatchers at Cape Lookout National Seashore by supplementing periodic visual observations with continuous 24-h video and audio recording at nests. Aircraft overflights were not associated with changes in Oystercatcher incubation behaviour, and we found no evidence that aircraft overflights influenced Oystercatcher reproductive success. However, Oystercatchers were on their nests significantly less often during off-road vehicle and pedestrian events than they were during control periods before the events, and an increase in the number of off-road vehicles passing a nest during incubation was consistently associated with significant reductions in daily nest survival (6% decrease in daily nest survival for a one-vehicle increase in the average number of vehicles passing a nest each day; odds ratio = 0.94; 95% confidence interval (CI) 0.90, 0.98) and hatching success (12% decrease in hatching success for a one-vehicle increase in the average number of vehicles passing a nest each day; odds ratio = 0.88; 95% CI 0.76, 0.97). Management of vehicles and pedestrians in areas of Oystercatcher breeding is important for the conservation of American Oystercatchers.

Summary of retrospective asbestos and welding fume exposure estimates for a nuclear naval shipyard and their correlation with radiation exposure estimates.

PubMed

Zaebst, D D; Seel, E A; Yiin, J H; Nowlin, S J; Chen, P

2009-07-01

In support of a nested case-control study at a U.S. naval shipyard, the results of the reconstruction of historical exposures were summarized, and an analysis was undertaken to determine the impact of historical exposures to potential chemical confounders. The nested case-control study (N = 4388) primarily assessed the relationship between lung cancer and external ionizing radiation. Chemical confounders considered important were asbestos and welding fume (as iron oxide fume), and the chromium and nickel content of welding fume. Exposures to the potential confounders were estimated by an expert panel based on a set of quantitatively defined categories of exposure. Distributions of the estimated exposures and trends in exposures over time were examined for the study population. Scatter plots and Spearman rank correlation coefficients were used to assess the degree of association between the estimates of exposure to asbestos, welding fume, and ionizing radiation. Correlation coefficients were calculated separately for 0-, 15-, 20-, and 25-year time-lagged cumulative exposures, total radiation dose (which included medical X-ray dose) and occupational radiation dose. Exposed workers' estimated cumulative exposures to asbestos ranged from 0.01 fiber-days/cm(3) to just under 20,000 fiber-days/cm(3), with a median of 29.0 fiber-days/cm(3). Estimated cumulative exposures to welding fume ranged from 0.16 mg-days/m(3) to just over 30,000 mg-days/m(3), with a median of 603 mg-days/m(3). Spearman correlation coefficients between cumulative radiation dose and cumulative asbestos exposures ranged from 0.09 (occupational dose) to 0.47 (total radiation dose), and those between radiation and welding fume from 0.14 to 0.47. The estimates of relative risk for ionizing radiation and lung cancer were unchanged when lowest and highest estimates of asbestos and welding fume were considered. These results suggest a fairly large proportion of study population workers were exposed to asbestos and welding fume, that the absolute level of confounding exposure did not affect the risk estimates, and that weak relationships existed between monitored lifetime cumulative occupational radiation dose and asbestos or welding fume.

Efficacy of fipronil for control of yellowjacket wasps in Hawaii Volcanoes National Park

USGS Publications Warehouse

Foote, David; Hanna, Cause; King, Cynthia; Spurr, Eric

2011-01-01

The western yellowjacket wasp (Vespula pensylvanica) invaded Hawai`i’s national parks and refuges following its spread throughout the islands in the late 1970s. The endemic arthropod fauna of Hawai`i is thought to be especially vulnerable to these predacious social Hymenoptera, and methods of wasp control have been a priority for conservation biology in Hawai`i. The efficacy of the insecticide fipronil mixed with minced canned chicken meat for suppression of yellowjacket populations was evaluated in five experimental field trials in Hawai`i Volcanoes National Park between 1999 and 2005. Populations of Vespula were monitored in replicate twoto four- hectare study areas in mesic montane and seasonal submontane forests, before and after application of chicken bait, with and without 0.1% fipronil, and in treatment and nontreatment areas. The bait was applied in hanging bait stations for two to three days. The response of yellowjacket wasp populations was measured using at least three different metrics of abundance including instantaneous counts of wasps at bait stations, wasp traffic rates at Vespula nests, as well as heptyl butyrate trap and/or malaise trap catches in the study areas. All indices of wasp abundance exhibited significant reductions in sites treated with fipronil compared with non-treatment sites with the exception of malaise trapping, where only a limited number of traps were available to be deployed. Wasp traffic ceased at all Vespula nests in sites treated with fipronil within a month after baiting in four of the five trials. The only trial where fipronil failed to terminate yellowjacket nest activity occurred late in the fall when wasps switch from feeding on protein to carbohydrate foods. Based on these data, 0.1% fipronil in chicken bait appears to be an effective tool for suppressing local Vespula yellowjacket populations in the park and other natural areas during the period of peak wasp activity in the summer and early fall months.

Selenium and breast cancer risk: A prospective nested case-control study on serum selenium levels, smoking habits and overweight.

PubMed

Sandsveden, Malte; Manjer, Jonas

2017-11-01

Previous research has not been conclusive regarding the association between selenium (Se) and breast cancer. This study was conducted to clarify if there is an association between prediagnostic serum Se levels and breast cancer risk. A population based cohort, the Malmö Diet and Cancer Study, was used and linked with the Swedish cancer registry up to 31 December 2013. Our study included 1,186 women with breast cancer and an equal number of controls. Selenium levels were analysed from stored serum samples. The included individuals were divided into quartiles based on Se value and we compared breast cancer cases with controls using logistic regression yielding odds ratios (OR) with 95% confidence intervals. Serum Se was also analysed as a continuous variable regarding breast cancer risk. The analyses were adjusted for established risk factors and stratified on smoking status and body mass index (BMI). When comparing the highest Se quartile with the lowest, the adjusted OR for breast cancer was 0.98 (0.75-1.26). With selenium as a continuous variable the adjusted OR was 1.00 (1.00-1.01) per 10 ng/ml. When comparing the highest with the lowest Se quartile in women with BMI > 25 kg/m 2 the adjusted OR was 0.77 (0.53-1.14). We conclude that it is unlikely that prediagnostic serum selenium is overall associated with breast cancer risk and no modifying effect from BMI or smoking was seen. © 2017 UICC.

Important Risk Factors of Mortality Among Children Aged 1-59 Months in Rural Areas of Shahroud, Iran: A Community-based Nested Case-Control Study.

PubMed

Chaman, Reza; Alami, Ali; Emamian, Mohammad Hassan; Naieni, Kourosh Holakouie; Mirmohammadkhani, Majid; Ahmadnezhad, Elham; Entezarmahdi, Rasool; Shati, Mohsen; Shariati, Mohammad

2012-12-01

The aim of the study was to evaluate potential risk factors of children mortality between 1-59 months of age. This nested case-control study was conducted among children born from June 1999 to March 2009 in rural areas of Shahroud, located in the central region of Iran using health care visit reports and follow-up data available in household health records. MORTALITY WAS SIGNIFICANTLY ASSOCIATED WITH BREASTFEEDING DURATION (OR: 0.87, 95% CI: 0.81-0.93), total health care visits (OR: 0.90, 95% CI: 0.83-0.98) and low birth weight (LBW) (OR: 7.38, 95% CI: 1.37-39.67). In our study, a longer breastfeeding period and more frequent health care visits were two important protective factors, while LBW was an important risk factor for 1-59 month child mortality. It seems, that complex and multiple factors may be involved in mortality of under 5-year-old children, so combined efforts would be necessary to improve child health indicators.

Nesting behavior of house mice (Mus domesticus) selected for increased wheel-running activity.

PubMed

Carter, P A; Swallow, J G; Davis, S J; Garland, T

2000-03-01

Nest building was measured in "active" (housed with access to running wheels) and "sedentary" (without wheel access) mice (Mus domesticus) from four replicate lines selected for 10 generations for high voluntary wheel-running behavior, and from four randombred control lines. Based on previous studies of mice bidirectionally selected for thermoregulatory nest building, it was hypothesized that nest building would show a negative correlated response to selection on wheel-running. Such a response could constrain the evolution of high voluntary activity because nesting has also been shown to be positively genetically correlated with successful production of weaned pups. With wheel access, selected mice of both sexes built significantly smaller nests than did control mice. Without wheel access, selected females also built significantly smaller nests than did control females, but only when body mass was excluded from the statistical model, suggesting that body mass mediated this correlated response to selection. Total distance run and mean running speed on wheels was significantly higher in selected mice than in controls, but no differences in amount of time spent running were measured, indicating a complex cause of the response of nesting to selection for voluntary wheel running.

Risk of treatment-related esophageal cancer among breast cancer survivors

PubMed Central

Morton, L. M.; Gilbert, E. S.; Hall, P.; Andersson, M.; Joensuu, H.; Vaalavirta, L.; Dores, G. M.; Stovall, M.; Holowaty, E. J.; Lynch, C. F.; Curtis, R. E.; Smith, S. A.; Kleinerman, R. A.; Kaijser, M.; Storm, H. H.; Pukkala, E.; Weathers, R. E.; Linet, M. S.; Rajaraman, P.; Fraumeni, J. F.; Brown, L. M.; van Leeuwen, F. E.; Fossa, S. D.; Johannesen, T. B.; Langmark, F.; Lamart, S.; Travis, L. B.; Aleman, B. M. P.

2012-01-01

Background Radiotherapy for breast cancer may expose the esophagus to ionizing radiation, but no study has evaluated esophageal cancer risk after breast cancer associated with radiation dose or systemic therapy use. Design Nested case–control study of esophageal cancer among 289 748 ≥5-year survivors of female breast cancer from five population-based cancer registries (252 cases, 488 individually matched controls), with individualized radiation dosimetry and information abstracted from medical records. Results The largest contributors to esophageal radiation exposure were supraclavicular and internal mammary chain treatments. Esophageal cancer risk increased with increasing radiation dose to the esophageal tumor location (Ptrend < 0.001), with doses of ≥35 Gy associated with an odds ratio (OR) of 8.3 [95% confidence interval (CI) 2.7–28]. Patients with hormonal therapy ≤5 years preceding esophageal cancer diagnosis had lower risk (OR = 0.4, 95% CI 0.2–0.8). Based on few cases, alkylating agent chemotherapy did not appear to affect risk. Our data were consistent with a multiplicative effect of radiation and other esophageal cancer risk factors (e.g. smoking). Conclusions Esophageal cancer is a radiation dose-related complication of radiotherapy for breast cancer, but absolute risk is low. At higher esophageal doses, the risk warrants consideration in radiotherapy risk assessment and long-term follow-up. PMID:22745217

Neck circumference might predict gestational diabetes mellitus in Han Chinese women: A nested case-control study.

PubMed

He, Fang; He, Hua; Liu, Wenqi; Lin, Junyu; Chen, Bingjun; Lin, Yucong; Zhao, Yitao; Tao, Wen; Xia, Xuefeng

2017-03-01

A large neck circumference might be an indicator of metabolic syndrome and its components, and for certain patients is more practical as an index than waist circumference. The demarcation value for neck circumference that suggests metabolic syndrome appears to vary by ethnic group. Gestational diabetes mellitus is considered a component of metabolic syndrome in pregnant women. We investigated whether neck circumference in Han Chinese women is associated with gestational diabetes mellitus in early pregnancy, and determined a predictive demarcation value. A nested case-control study was carried out with 255 women aged 18-35 years. Gestational diabetes mellitus was diagnosed according to the criteria of the American Diabetes Association through a 2-h, 75-g oral glucose tolerance test. Of the total population, 41 (16%) women developed gestational diabetes mellitus by 24-28 weeks of gestation. Neck circumference at gestational week 16 positively correlated with pre-pregnancy waist circumference, bodyweight and body mass index, and maternal age (P = 0.029) and hemoglobin A1c at gestational week 24 (P ≤ 0.001). By binary logistic regression, neck circumference was an independent predictor of gestational diabetes mellitus (odds ratio 1.840, 95% confidence interval 1.040-3.254; P = 0.036). According to the receiver operating characteristic curve, for predicting gestational diabetes mellitus the optimal demarcation for neck circumference at gestational week 16 was 35.15 cm. Neck circumference is a viable tool to screen for gestational diabetes mellitus. In this population of pregnant Han Chinese women, a neck circumference of ≥35.15 cm was a predictor of gestational diabetes mellitus. © 2016 The Authors. Journal of Diabetes Investigation published by Asian Association for the Study of Diabetes (AASD) and John Wiley & Sons Australia, Ltd.

Decoration Increases the Conspicuousness of Raptor Nests

PubMed Central

Canal, David; Mulero-Pázmány, Margarita; Negro, Juan José; Sergio, Fabrizio

2016-01-01

Avian nests are frequently concealed or camouflaged, but a number of species builds noticeable nests or use conspicuous materials for nest decoration. In most cases, nest decoration has a role in mate choice or provides thermoregulatory or antiparasitic benefits. In territorial species however, decorations may serve additional or complementary functions, such as extended phenotypic signaling of nest-site occupancy and social status to potential intruders. The latter may benefit both signaler and receiver by minimizing the risk of aggressive interactions, especially in organisms with dangerous weaponry. Support for this hypothesis was recently found in a population of black kites (Milvus migrans), a territorial raptor that decorates its nest with white artificial materials. However, the crucial assumption that nest decorations increased nest-site visibility to conspecifics was not assessed, a key aspect given that black kite nests may be well concealed within the canopy. Here, we used an unmanned aircraft system to take pictures of black kite nests, with and without an experimentally placed decoration, from different altitudes and distances simulating the perspective of a flying and approaching, prospecting intruder. The pictures were shown to human volunteers through a standardized routine to determine whether detection rates varied according the nest decoration status and distance. Decorated nests consistently showed a higher detection frequency and a lower detection-latency, compared to undecorated versions of the same nests. Our results confirm that nest decoration in this species may act as a signaling medium that enhances nest visibility for aerial receivers, even at large distances. This finding complements previous work on this communication system, which showed that nest decoration was a threat informing trespassing conspecifics on the social dominance, territory quality and fighting capabilities of the signaler. PMID:27455066

Decoration Increases the Conspicuousness of Raptor Nests.

PubMed

Canal, David; Mulero-Pázmány, Margarita; Negro, Juan José; Sergio, Fabrizio

2016-01-01

Avian nests are frequently concealed or camouflaged, but a number of species builds noticeable nests or use conspicuous materials for nest decoration. In most cases, nest decoration has a role in mate choice or provides thermoregulatory or antiparasitic benefits. In territorial species however, decorations may serve additional or complementary functions, such as extended phenotypic signaling of nest-site occupancy and social status to potential intruders. The latter may benefit both signaler and receiver by minimizing the risk of aggressive interactions, especially in organisms with dangerous weaponry. Support for this hypothesis was recently found in a population of black kites (Milvus migrans), a territorial raptor that decorates its nest with white artificial materials. However, the crucial assumption that nest decorations increased nest-site visibility to conspecifics was not assessed, a key aspect given that black kite nests may be well concealed within the canopy. Here, we used an unmanned aircraft system to take pictures of black kite nests, with and without an experimentally placed decoration, from different altitudes and distances simulating the perspective of a flying and approaching, prospecting intruder. The pictures were shown to human volunteers through a standardized routine to determine whether detection rates varied according the nest decoration status and distance. Decorated nests consistently showed a higher detection frequency and a lower detection-latency, compared to undecorated versions of the same nests. Our results confirm that nest decoration in this species may act as a signaling medium that enhances nest visibility for aerial receivers, even at large distances. This finding complements previous work on this communication system, which showed that nest decoration was a threat informing trespassing conspecifics on the social dominance, territory quality and fighting capabilities of the signaler.

Assessing relative abundance and reproductive success of shrubsteppe raptors

USGS Publications Warehouse

Lehman, Robert N.; Carpenter, L.B.; Steenhof, Karen; Kochert, Michael N.

1998-01-01

From 1991-1994, we quantified relative abundance and reproductive success of the Ferruginous Hawk (Buteo regalis), Northern Harrier (Circus cyaneus), Burrowing Owl (Speotytoc unicularia), and Short-eared Owl (Asio flammeus) on the shrubsteppe plateaus (benchlands) in and near the Snake River Birds of Prey National Conservation Area in southwestern Idaho. To assess relative abundance, we searched randomly selected plots using four sampling methods: point counts, line transects, and quadrats of two sizes. On a persampling-effort basis, transects were slightly more effective than point counts and quadrats for locating raptor nests (3.4 pairs detected/100 h of effort vs. 2.2-3.1 pairs). Random sampling using quadrats failed to detect a Short-eared Owl population increase from 1993 to 1994. To evaluate nesting success, we tried to determine reproductive outcome for all nesting attempts located during random, historical, and incidental nest searches. We compared nesting success estimates based on all nesting attempts, on attempts found during incubation, and the Mayfield model. Most pairs used to evaluate success were pairs found incidentally. Visits to historical nesting areas yielded the highest number of pairs per sampling effort (14.6/100 h), but reoccupancy rates for most species decreased through time. Estimates based on all attempts had the highest sample sizes but probably overestimated success for all species except the Ferruginous Hawk. Estimates of success based on nesting attempts found during incubation had the lowest sample sizes. All three methods yielded biased nesting snccess estimates for the Northern Harrier and Short-eared Owl. The estimate based on pairs found during incubation probably provided the least biased estimate for the Burrowing Owl. Assessments of nesting success were hindered by difficulties in confirming egg laying and nesting success for all species except the Ferruginous hawk.

Foraging habitat quality constrains effectiveness of artificial nest-site provisioning in reversing population declines in a colonial cavity nester.

PubMed

Catry, Inês; Franco, Aldina M A; Rocha, Pedro; Alcazar, Rita; Reis, Susana; Cordeiro, Ana; Ventim, Rita; Teodósio, Joaquim; Moreira, Francisco

2013-01-01

Among birds, breeding numbers are mainly limited by two resources of major importance: food supply and nest-site availability. Here, we investigated how differences in land-use and nest-site availability affected the foraging behaviour, breeding success and population trends of the colonial cavity-dependent lesser kestrel Falco naumanni inhabiting two protected areas. Both areas were provided with artificial nests to increase nest-site availability. The first area is a pseudo-steppe characterized by traditional extensive cereal cultivation, whereas the second area is a previous agricultural zone now abandoned or replaced by forested areas. In both areas, lesser kestrels selected extensive agricultural habitats, such as fallows and cereal fields, and avoided scrubland and forests. In the second area, tracked birds from one colony travelled significantly farther distances (6.2 km ± 1.7 vs. 1.8 km ± 0.4 and 1.9 km ± 0.6) and had significant larger foraging-ranges (144 km(2) vs. 18.8 and 14.8 km(2)) when compared to the birds of two colonies in the extensive agricultural area. Longer foraging trips were reflected in lower chick feeding rates, lower fledging success and reduced chick fitness. Availability and occupation of artificial nests was high in both areas but population followed opposite trends, with a positive increment recorded exclusively in the first area with a large proportion of agricultural areas. Progressive habitat loss around the studied colony in the second area (suitable habitat decreased from 32% in 1990 to only 7% in 2002) is likely the main driver of the recorded population decline and suggests that the effectiveness of bird species conservation based on nest-site provisioning is highly constrained by habitat quality in the surrounding areas. Therefore, the conservation of cavity-dependent species may be enhanced firstly by finding the best areas of remaining habitat and secondly by increasing the carrying capacity of high-quality habitat areas through safe nest-site provisioning.

Foraging Habitat Quality Constrains Effectiveness of Artificial Nest-Site Provisioning in Reversing Population Declines in a Colonial Cavity Nester

PubMed Central

Catry, Inês; Franco, Aldina M. A.; Rocha, Pedro; Alcazar, Rita; Reis, Susana; Cordeiro, Ana; Ventim, Rita; Teodósio, Joaquim; Moreira, Francisco

2013-01-01

Among birds, breeding numbers are mainly limited by two resources of major importance: food supply and nest-site availability. Here, we investigated how differences in land-use and nest-site availability affected the foraging behaviour, breeding success and population trends of the colonial cavity-dependent lesser kestrel Falco naumanni inhabiting two protected areas. Both areas were provided with artificial nests to increase nest-site availability. The first area is a pseudo-steppe characterized by traditional extensive cereal cultivation, whereas the second area is a previous agricultural zone now abandoned or replaced by forested areas. In both areas, lesser kestrels selected extensive agricultural habitats, such as fallows and cereal fields, and avoided scrubland and forests. In the second area, tracked birds from one colony travelled significantly farther distances (6.2 km ±1.7 vs. 1.8 km ±0.4 and 1.9 km ±0.6) and had significant larger foraging-ranges (144 km2 vs. 18.8 and 14.8 km2) when compared to the birds of two colonies in the extensive agricultural area. Longer foraging trips were reflected in lower chick feeding rates, lower fledging success and reduced chick fitness. Availability and occupation of artificial nests was high in both areas but population followed opposite trends, with a positive increment recorded exclusively in the first area with a large proportion of agricultural areas. Progressive habitat loss around the studied colony in the second area (suitable habitat decreased from 32% in 1990 to only 7% in 2002) is likely the main driver of the recorded population decline and suggests that the effectiveness of bird species conservation based on nest-site provisioning is highly constrained by habitat quality in the surrounding areas. Therefore, the conservation of cavity-dependent species may be enhanced firstly by finding the best areas of remaining habitat and secondly by increasing the carrying capacity of high-quality habitat areas through safe nest-site provisioning. PMID:23484016

Decline in a population of spectacled eiders nesting on the Yukon-Kuskokwim Delta, Alaska

USGS Publications Warehouse

Ely, Craig R.; Dau, Christian; Babcock, Christopher

1994-01-01

The number of spectacled eiders nesting on two study areas near the Kashunuk River, on the central Yukon-Kuskokwim (Y-K) Delta, Alaska, declined by over 75% in the last 20 years. Nesting densities have remained low, but have not significantly declined since 1985. There has been no decrease in the reproductive effort of individual females as indicated by average clutch sizes. There has been a significant decline in the proportion of nests located on islands on one of the two study areas. Nesting success declined significantly during the 1970's. Success was not monitored in recent years, but has likely been low, based on the poor nesting success and declining numbers of cackling Canada geese and black brant nesting on the area. Nest predation by arctic foxes severely limited the productivity of cackling Canada geese, and foxes were likely the major predators of eider nests. Persistent high predation rates may lead to local extirpation in highly philopatric species such as eiders.

Radiation Dose and Subsequent Risk for Stomach Cancer in Long-term Survivors of Cervical Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kleinerman, Ruth A., E-mail: kleinerr@mail.nih.gov; Smith, Susan A.; Holowaty, Eric

2013-08-01

Purpose: To assess the dose–response relationship for stomach cancer after radiation therapy for cervical cancer. Methods and Materials: We conducted a nested, matched case–control study of 201 cases and 378 controls among 53,547 5-year survivors of cervical cancer diagnosed from 1943 to 1995, from 5 international, population-based cancer registries. We estimated individual radiation doses to the site of the stomach cancer for all cases and to corresponding sites for the matched controls (overall mean stomach tumor dose, 2.56 Gy, range 0.03-46.1 and after parallel opposed pelvic fields, 1.63 Gy, range 0.12-6.3). Results: More than 90% of women received radiation therapy,more » mostly with external beam therapy in combination with brachytherapy. Stomach cancer risk was nonsignificantly increased (odds ratio 1.27-2.28) for women receiving between 0.5 and 4.9 Gy to the stomach cancer site and significantly increased at doses ≥5 Gy (odds ratio 4.20, 95% confidence interval 1.41-13.4, P{sub trend}=.047) compared with nonirradiated women. A highly significant radiation dose–response relationship was evident when analyses were restricted to the 131 cases (251 controls) whose stomach cancer was located in the middle and lower portions of the stomach (P{sub trend}=.003), whereas there was no indication of increasing risk with increasing dose for 30 cases (57 controls) whose cancer was located in the upper stomach (P{sub trend}=.23). Conclusions: Our findings show for the first time a significant linear dose–response relationship for risk of stomach cancer in long-term survivors of cervical cancer.« less

Evaluation of efficiency of nested multiplex allele-specific PCR assay for detection of multidrug resistant tuberculosis directly from sputum samples.

PubMed

Mistri, S K; Sultana, M; Kamal, S M M; Alam, M M; Irin, F; Nessa, J; Ahsan, C R; Yasmin, M

2016-05-01

For an effective control of tuberculosis, rapid detection of multidrug resistant tuberculosis (MDR-TB) is necessary. Therefore, we developed a modified nested multiplex allele-specific polymerase chain reaction (MAS-PCR) method that enables rapid MDR-TB detection directly from sputum samples. The efficacy of this method was evaluated using 79 sputum samples collected from suspected tuberculosis patients. The performance of nested MAS-PCR method was compared with other MDR-TB detection methods like drug susceptibility testing (DST) and DNA sequencing. As rifampicin (RIF) resistance conforms to MDR-TB in greater than 90% cases, only the presence of RIF-associated mutations in rpoB gene was determined by DNA sequencing and nested MAS-PCR to detect MDR-TB. The concordance between nested MAS-PCR and DNA sequencing results was found to be 96·3%. When compared with DST, the sensitivity and specificity of nested MAS-PCR for RIF-resistance detection were determined to be 92·9 and 100% respectively. For developing- and high-TB burden countries, molecular-based tests have been recommended by the World Health Organization for rapid detection of MDR-TB. The results of this study indicate that, nested MAS-PCR assay might be a practical and relatively cost effective molecular method for rapid detection of MDR-TB from suspected sputum samples in developing countries with resource poor settings. © 2016 The Society for Applied Microbiology.

Coordinating compass-based and nest-based flight directions during bumblebee learning and return flights.

PubMed

Collett, Thomas S; de Ibarra, Natalie Hempel; Riabinina, Olena; Philippides, Andrew

2013-03-15

Bumblebees tend to face their nest over a limited range of compass directions when learning the nest's location on departure and finding it on their approach after foraging. They thus obtain similar views of the nest and its surroundings on their learning and return flights. How do bees coordinate their flights relative to nest-based and compass-based reference frames to get such similar views? We show, first, that learning and return flights contain straight segments that are directed along particular compass bearings, which are independent of the orientation of a bee's body. Bees are thus free within limits to adjust their viewing direction relative to the nest, without disturbing flight direction. Second, we examine the coordination of nest-based and compass-based control during likely information gathering segments of these flights: loops during learning flights and zigzags on return flights. We find that bees tend to start a loop or zigzag when flying within a restricted range of compass directions and to fly towards the nest and face it after a fixed change in compass direction, without continuous interactions between their nest-based and compass-based directions of flight. A preferred trajectory of compass-based flight over the course of a motif, combined with the tendency of the bees to keep their body oriented towards the nest automatically narrows the range of compass directions over which bees view the nest. Additionally, the absence of interactions between the two reference frames allows loops and zigzags to have a stereotyped form that can generate informative visual feedback.

What, How and Why? A Multi-Dimensional Case Analysis of the Challenges Facing Native and Non- Native EFL Teachers

ERIC Educational Resources Information Center

Demir, Yusuf

2017-01-01

On a multifaceted basis, this paper explores the challenges experienced by native and non-native English language teachers (NESTs and NNESTs) in a tertiary-level EFL setting in Turkey. Adopting a qualitative case study design, the data were gathered from five NESTs through interviews and from five NNESTs through hand-written accounts based on the…

Anti-predator meshing may provide greater protection for sea turtle nests than predator removal.

PubMed

O'Connor, Julie M; Limpus, Colin J; Hofmeister, Kate M; Allen, Benjamin L; Burnett, Scott E

2017-01-01

The problem of how to protect sea turtle nests from terrestrial predators is of worldwide concern. On Queensland's southern Sunshine Coast, depredation of turtle nests by the introduced European red fox (Vulpes vulpes) has been recorded as the primary terrestrial cause of egg and hatchling mortality. We investigated the impact of foxes on the nests of the loggerhead turtle (Caretta caretta) and occasional green turtle (Chelonia mydas) over ten nesting seasons. Meshing of nests with fox exclusion devices (FEDs) was undertaken in all years accompanied by lethal fox control in the first five-year period, but not in the second five-year period. Lethal fox control was undertaken in the study area from 2005 to February 2010, but foxes still breached 27% (range19-52%) of turtle nests. In the second five-year period, despite the absence of lethal fox control, the average percentage of nests breached was less than 3% (range 0-4%). Comparison of clutch depredation rates in the two five-year periods demonstrated that continuous nest meshing may be more effective than lethal fox control in mitigating the impact of foxes on turtle nests. In the absence of unlimited resources available for the eradication of exotic predators, the use of FEDs and the support and resourcing of a dedicated volunteer base can be considered an effective turtle conservation tool on some beaches.

HIV infection among U.S. Army and Air Force military personnel: sociodemographic and genotyping analysis.

PubMed

Singer, Darrell E; Bautista, Christian T; O'Connell, Robert J; Sanders-Buell, Eric; Agan, Brian K; Kijak, Gustavo H; Hakre, Shilpa; Sanchez, Jose L; Sateren, Warren B; McCutchan, Francine E; Michael, Nelson L; Scott, Paul T

2010-08-01

Since 1985, the U.S. Department of Defense has periodically screened all military personnel for HIV allowing for the monitoring of the infection in this dynamic cohort population. A nested case-control study was performed to study sociodemographics, overseas assignment, and molecular analysis of HIV. Cases were newly identified HIV infections among U.S. Army and Air Force military personnel from 2000 to 2004. Controls were frequency matched to cases by gender and date of case first positive HIV screening test. Genotyping analysis was performed using high-throughput screening assays and partial genome sequencing. HIV was significantly associated with black race [odds ratio (OR) = 6.65], single marital status (OR = 4.45), and age (OR per year = 1.07). Ninety-seven percent were subtype B and 3% were non-B subtypes (A3, CRF01_AE, A/C recombinant, G, CRF02_AG). Among cases, overseas assignment in the period at risk prior to their first HIV-positive test was associated with non-B HIV subtype infection (OR = 8.44). Black and single military personnel remain disproportionately affected by HIV infection. Most non-B HIV subtypes were associated with overseas assignment. Given the increased frequency and length of assignments, and the expanding HIV genetic diversity observed in this population, there is a need for active HIV genotyping surveillance and a need to reinforce primary HIV prevention efforts.

Lack of association between genetic polymorphisms of CYP3A4, CYP2C9 and CYP2C19 and antituberculosis drug-induced liver injury in a community-based Chinese population.

PubMed

Tang, Shao-Wen; Lv, Xiao-Zhen; Chen, Ru; Wu, Shan-Shan; Yang, Zhi-Rong; Chen, Da-Fang; Zhan, Si-Yan

2013-05-01

The precise pathogenic mechanism of antituberculosis (anti-TB) drug-induced liver injury (ATLI) is poorly understood. It may be associated with drug-metabolizing enzymes, such as cytochrome P450 (CYP) 3A4, CYP2C9 and CYP2C19. The aim of the present study was to explore the role of tagging single nucleotide polymorphisms (tSNPs) of CYP3A4, CYP2C9 and CYP2C19 in the risk of ATLI in a population-based anti-TB treatment cohort. A nested case-control study was designed. Each ATLI case was matched 1 : 4 with controls on the basis of age, gender, treatment history, disease severity and drug dosage. The tSNPs were selected using Haploview 4.2 based on the HapMap database of Han Chinese in Beijing and genotyped by TaqMan allelic discrimination technology. Eighty-nine patients with ATLI and 356 controls were included in the study. One tSNP in CYP3A4 (rs12333983), two in CYP2C9 (rs4918758, rs9332098) and two in CYP2C19 (rs11568732, rs4986894) were selected and genotyped. The minor allele frequencies of rs12333983, rs4918758, rs9332098, rs11568732 and rs4986894 were 36.0%, 41.4%, 1.1%, 5.7% and 35.7%, respectively, in the patients, compared with 31.7%, 42.9%, 3.4%, 8.9% and 35.1%, respectively, in the controls. No significant differences were observed in genotypes or allele frequencies of the five tSNPs between the two groups and none of the CYP2C9 or CYP2C19 haplotypes was significantly associated with the development of ATLI. Based on the Chinese anti-TB treatment cohort, we did not find a significant association between the risk of ATLI and genetic polymorphisms of CYP3A4, CYP2C9 and CYP2C19. None of the haplotypes exhibited a significant association with the development of ATLI in a Chinese tuberculosis population. © 2013 The Authors Clinical and Experimental Pharmacology and Physiology © 2013 Wiley Publishing Asia Pty Ltd.

Increasing nest predation will be insufficient to maintain polar bear body condition in the face of sea ice loss.

PubMed

Dey, Cody J; Richardson, Evan; McGeachy, David; Iverson, Samuel A; Gilchrist, Hugh G; Semeniuk, Christina A D

2017-05-01

Climate change can influence interspecific interactions by differentially affecting species-specific phenology. In seasonal ice environments, there is evidence that polar bear predation of Arctic bird eggs is increasing because of earlier sea ice breakup, which forces polar bears into nearshore terrestrial environments where Arctic birds are nesting. Because polar bears can consume a large number of nests before becoming satiated, and because they can swim between island colonies, they could have dramatic influences on seabird and sea duck reproductive success. However, it is unclear whether nest foraging can provide an energetic benefit to polar bear populations, especially given the capacity of bird populations to redistribute in response to increasing predation pressure. In this study, we develop a spatially explicit agent-based model of the predator-prey relationship between polar bears and common eiders, a common and culturally important bird species for northern peoples. Our model is composed of two types of agents (polar bear agents and common eider hen agents) whose movements and decision heuristics are based on species-specific bioenergetic and behavioral ecological principles, and are influenced by historical and extrapolated sea ice conditions. Our model reproduces empirical findings that polar bear predation of bird nests is increasing and predicts an accelerating relationship between advancing ice breakup dates and the number of nests depredated. Despite increases in nest predation, our model predicts that polar bear body condition during the ice-free period will continue to decline. Finally, our model predicts that common eider nests will become more dispersed and will move closer to the mainland in response to increasing predation, possibly increasing their exposure to land-based predators and influencing the livelihood of local people that collect eider eggs and down. These results show that predator-prey interactions can have nonlinear responses to changes in climate and provides important predictions of ecological change in Arctic ecosystems. © 2016 John Wiley & Sons Ltd.

Linking occurrence and fitness to persistence: Habitat-based approach for endangered Greater Sage-Grouse

USGS Publications Warehouse

Aldridge, Cameron L.; Boyce, Mark S.

2007-01-01

Detailed empirical models predicting both species occurrence and fitness across a landscape are necessary to understand processes related to population persistence. Failure to consider both occurrence and fitness may result in incorrect assessments of habitat importance leading to inappropriate management strategies. We took a two-stage approach to identifying critical nesting and brood-rearing habitat for the endangered Greater Sage-Grouse (Centrocercus urophasianus) in Alberta at a landscape scale. First, we used logistic regression to develop spatial models predicting the relative probability of use (occurrence) for Sage-Grouse nests and broods. Secondly, we used Cox proportional hazards survival models to identify the most risky habitats across the landscape. We combined these two approaches to identify Sage-Grouse habitats that pose minimal risk of failure (source habitats) and attractive sink habitats that pose increased risk (ecological traps). Our models showed that Sage-Grouse select for heterogeneous patches of moderate sagebrush cover (quadratic relationship) and avoid anthropogenic edge habitat for nesting. Nests were more successful in heterogeneous habitats, but nest success was independent of anthropogenic features. Similarly, broods selected heterogeneous high-productivity habitats with sagebrush while avoiding human developments, cultivated cropland, and high densities of oil wells. Chick mortalities tended to occur in proximity to oil and gas developments and along riparian habitats. For nests and broods, respectively, approximately 10% and 5% of the study area was considered source habitat, whereas 19% and 15% of habitat was attractive sink habitat. Limited source habitats appear to be the main reason for poor nest success (39%) and low chick survival (12%). Our habitat models identify areas of protection priority and areas that require immediate management attention to enhance recruitment to secure the viability of this population. This novel approach to habitat-based population viability modeling has merit for many species of concern. ?? 2007 by the Ecological Society of America.

Young people's risk of suicide attempts after contact with a psychiatric department - a nested case-control design using Danish register data.

PubMed

Christiansen, Erik; Larsen, Kim Juul

2012-01-01

There seems to be an increased risk of children and adolescents committing or attempting suicide after contact with a psychiatric department. Children and adolescents living in families with low socio-economic status (SES) might have an especially increased suicide attempt risk. A complete extraction of Danish register data for every individual born in the period 1983-1989 was made. Of these 403,431 individuals, 3,465 had attempted suicide. In order to control for confounder effects from gender, age and calendar-time, a nested case-control study was designed. A total population of 72,765 individuals was used to analyze the risk of suicide attempts after contact with a psychiatric department. The case-control data were analyzed using conditional logistic regression. This study shows that a child/adolescent's risk of suicide attempt peaks immediately after discharge from last contact with a psychiatric department. The risk of suicide attempt is highest for children and adolescents suffering from personality disorders, depression and substance use disorders. Children and adolescents with previous contact with a psychiatric department and parental income in the lowest third have a significantly higher risk of suicide attempt. Suicide attempters were more likely to have been given several different diagnoses and several different psychopharmacological drugs prior to their attempted suicide. The findings in this study highlight the need for psychopathology assessment in every case of attempted suicide. This study also shows that well-known risk factors such as contact with a psychiatric department do not affect all individuals in the same way. Individuals from families with low SES had the highest risk. This suggests that the presence of factors influencing both vulnerability and resiliency, e.g., family level of SES, needs to be included in the assessment. © 2011 The Authors. Journal of Child Psychology and Psychiatry © 2011 Association for Child and Adolescent Mental Health.

The impact of overactive bladder, incontinence and other lower urinary tract symptoms on quality of life, work productivity, sexuality and emotional well-being in men and women: results from the EPIC study.

PubMed

Coyne, Karin S; Sexton, Chris C; Irwin, Debra E; Kopp, Zoe S; Kelleher, Con J; Milsom, Ian

2008-06-01

To examine the effect overactive bladder (OAB) and other lower urinary tract symptoms (LUTS) on health-related quality of life (HRQoL) in a population sample, as OAB often occurs in conjunction with many other LUTS. A nested case-control analysis was performed on men and women with (cases) and without (controls) OAB, from the EPIC study. OAB was assessed using 2002 International Continence Society definitions. Based on their responses to questions about LUTS, cases were classified into five groups; continent OAB, OAB with incontinence, OAB + postmicturition, OAB + voiding, and OAB + postmicturition + voiding. Both cases and controls were asked questions about symptom bother (OAB-q), generic QoL (EQ-5D), work productivity (Work Productivity and Activity Impairment, WPAI), depressive symptoms (Center for Epidemiologic Studies Depression Scale), sexual satisfaction, and erectile dysfunction (men only) using the Massachusetts Male Aging Study. Cases answered additional condition-specific questions HRQoL (OAB-q short form), Patient Perception of Bladder Condition and work productivity related to a specific health problem (WPAI-SHP). General linear models were used to evaluate group differences. Of the EPIC participants, 1434 identified OAB cases were matched by age, gender and country, with 1434 participants designated as controls. Cases and controls were primarily Caucasian (96.2% and 96.7%, respectively), and most (65%) were female; the mean age was 53.8 and 53.7 years, respectively. Comorbid conditions differed significantly by case/control status, with cases reporting significantly greater rates of chronic constipation, asthma, diabetes, high blood pressure, bladder or prostate cancer, neurological conditions and depression. There were significant differences between the cases and controls in all reported LUTS. The OAB + postmicturition + voiding group reported significantly greater symptom bother, worse HRQoL, higher rates of depression and decreased enjoyment of sexual activity, than the other subgroups. OAB has a substantial, multidimensional impact on patients; OAB with additional LUTS has a greater impact. The diagnosis and treatment of OAB should be considered in conjunction with other LUTS, to maximize treatment options and optimize patient outcomes.

Climate change and temperature-dependent sex determination: can individual plasticity in nesting phenology prevent extreme sex ratios?

PubMed

Schwanz, Lisa E; Janzen, Fredric J

2008-01-01

Under temperature-dependent sex determination (TSD), temperatures experienced by embryos during development determine the sex of the offspring. Consequently, populations of organisms with TSD have the potential to be strongly impacted by climatic warming that could bias offspring sex ratio, a fundamental demographic parameter involved in population dynamics. Moreover, many taxa with TSD are imperiled, so research on this phenomenon, particularly long-term field study, has assumed great urgency. Recently, turtles with TSD have joined the diverse list of taxa that have demonstrated population-level changes in breeding phenology in response to recent climate change. This raises the possibility that any adverse impacts of climate change on populations may be alleviated by individual plasticity in nesting phenology. Here, we examine data from a long-term study on a population of painted turtles (Chrysemys picta) to determine whether changes in phenology are due to individual plasticity and whether individual plasticity in the timing of nesting has the capacity to offset the sex ratio effects of a rise in climatic temperature. We find that individual females show plasticity in the date of first nesting each year, and that this plasticity depends on the climate from the previous winter. First nesting date is not repeatable within individuals, suggesting that it would not respond to selection. Sex ratios of hatchlings within a nest declined nonsignificantly over the nesting season. However, small increases in summer temperature had a much stronger effect on nest sex ratios than did laying nests earlier in the season. For this and other reasons, it seems unlikely that individual plasticity in the timing of nesting will offset the effects of climate change on sex ratios in this population, and we hypothesize that this conclusion applies to other populations with TSD.

Current status and recent dynamics of the Black Brant Branta bernicla breeding population

USGS Publications Warehouse

Sedinger, James S.; Lensink, Calvin J.; Ward, David H.; Anthony, Michael W.; Wege, Michael L.; Byrd, G. Vernon

1993-01-01

We summarize current knowledge about the distribution of Pacific Black Brant and recent dynamics of colonies, particularly on the Yukon-Kuskokwim (Y-K) Delta, Alaska. About 20,000 nests are required to produce the number of young in the autumn flight using estimates of clutch size, hatching success and gosling survival based on colonies on the Y-K Delta. More than 80% of the nests in the population can be accounted for currently on the Y-K Delta. Most moulting individuals that did not breed, or were unsuccessful, are unaccounted for in late summer. Numbers of Black Brant nesting in major colonies on the Y-K Delta declined >60% in the early 1980s, most likely as a result of local subsistence harvest combined with predation by arctic foxes. Effective management of this population requires a better understanding of the distribution of breeding and moulting birds, the importance of breeding habitat to colony dynamics and the role of both sport and subsistence harvest in population dynamics.

Nest design in a changing world: great tit Parus major nests from a Mediterranean city environment as a case study.

PubMed

Lambrechts, Marcel M; Charmantier, Anne; Demeyrier, Virginie; Lucas, Annick; Perret, Samuel; Abouladzé, Matthieu; Bonnet, Michel; Canonne, Coline; Faucon, Virginie; Grosset, Stéphanie; le Prado, Gaëlle; Lidon, Frédéric; Noell, Thierry; Pagano, Pascal; Perret, Vincent; Pouplard, Stéphane; Spitaliéry, Rémy; Bernard, Cyril; Perret, Philippe; Blondel, Jacques; Grégoire, Arnaud

2017-12-01

Investigations of urbanization effects on birds have focused mainly on breeding traits expressed after the nest-building stage (e.g. first-egg date, clutch size, breeding success, and offspring characteristics). Urban studies largely ignored how and why the aspects of nest building might be associated with the degree of urbanization. As urban environments are expected to present novel environmental changes relative to rural environments, it is important to evaluate how nest-building behavior is impacted by vegetation modifications associated with urbanization. To examine nest design in a Mediterranean city environment, we allowed urban great tits ( Parus major ) to breed in nest boxes in areas that differed in local vegetation cover. We found that different measures of nest size or mass were not associated with vegetation cover. In particular, nests located adjacent to streets with lower vegetation cover were not smaller or lighter than nests in parks with higher vegetation cover. Nests adjacent to streets contained more pine needles than nests in parks. In addition, in nests adjacent to streets, nests from boxes attached to pine trees contained more pine needles than nests from boxes attached to other trees. We suggest that urban-related alterations in vegetation cover do not directly impose physical limits on nest size in species that are opportunistic in the selection of nesting material. However, nest composition as reflected in the use of pine needles was clearly affected by habitat type and the planted tree species present, which implies that rapid habitat change impacts nest composition. We do not exclude that urbanization might impact other aspects of nest building behaviour not covered in our study (e.g. costs of searching for nest material), and that the strengths of the associations between urbanization and nest structures might differ among study populations or species.

Assessing Attachment with the Bird's Nest Drawing: A Review of the Research

ERIC Educational Resources Information Center

Kaiser, Donna H.; Deaver, Sarah

2009-01-01

The Bird's Nest Drawing (Kaiser, 1996) is an art-based assessment that was developed to assess attachment security. In the past 10 years, several studies have further tested this art therapy directive with various populations. This paper briefly reviews attachment theory, delineates the significant findings from five of the studies, and provides…

Blood Erythrocyte Concentrations of Cadmium and Lead and the Risk of B-Cell Non-Hodgkin’s Lymphoma and Multiple Myeloma: A Nested Case-Control Study

PubMed Central

Porta, Miquel; Bergdahl, Ingvar A.; Palli, Domenico; Johansson, Ann-Sofie; Botsivali, Maria; Vineis, Paolo; Vermeulen, Roel; Kyrtopoulos, Soterios A.; Chadeau-Hyam, Marc

2013-01-01

Background Cadmium (Cd) and lead (Pb) are hypothesised to be risk factors for non-Hodgkin’s lymphoma (NHL), a group of haematological malignancies with a suspected environmental aetiology. Within the EnviroGenoMarkers study we utilised pre-diagnostic erythrocyte concentrations of Cd and Pb to determine whether exposure was associated with risk of B-cell NHL and multiple myeloma. Methods 194 incident cases of B-cell NHL and 76 cases of multiple myeloma diagnosed between 1990 and 2006 were identified from two existing cohorts; EPIC-Italy and the Northern Sweden Health and Disease Study. Cases were matched to healthy controls by centre, age, gender and date of blood collection. Cd and Pb were measured in blood samples provided at recruitment using inductively coupled plasma-mass spectrometry. Logistic regression was applied to assess the association with risk. Analyses were stratified by cohort and gender and by subtype where possible. Results There was little evidence of an increased risk of B-cell NHL or multiple myeloma with exposure to Cd (B-cell NHL: OR 1.09 95%CI 0.61, 1.93, MM: OR 1.16 95% CI: 0.40, 3.40 ) or Pb (B-cell NHL: 0.93 95% CI 0.43, 2.02, multiple myeloma: OR 1.63 95%CI 0.45, 5.94) in the total population when comparing the highest to the lowest quartile of exposure. However, gender and cohort specific differences in results were observed. In females the risk of B-cell NHL was more than doubled in those with a body burden of Cd >1µg/L (OR 2.20 95%CI; 1.04, 4.65). Conclusions This nested case-control study does not support a consistent positive association between Cd or Pb and NHL, but there is some indication of a gender specific effect suggesting further research is warranted. PMID:24312375

Maternal hormone levels and risk of cryptorchism among populations at high and low risk of testicular germ cell tumors.

PubMed

McGlynn, Katherine A; Graubard, Barry I; Nam, Jun-Mo; Stanczyk, Frank Z; Longnecker, Matthew P; Klebanoff, Mark A

2005-07-01

Cryptorchism is one of the few well-described risk factors for testicular cancer. It has been suggested that both conditions are related to increased in utero estrogen exposure. The evidence supporting the "estrogen hypothesis" has been inconsistent, however. An alternative hypothesis suggests that higher in utero androgen exposure may protect against the development of cryptorchism and testicular cancer. In order to examine both hypotheses, we studied maternal hormone levels in two populations at diverse risks of testicular cancer; Black Americans (low-risk) and White Americans (high-risk). The study population of 200 mothers of cryptorchid sons and 200 mothers of noncryptorchid sons was nested within the Collaborative Perinatal Project, a cohort study of pregnant women and their children. Third trimester serum levels of estradiol (total, free, bioavailable), estriol, testosterone (total, free, bioavailable), sex hormone-binding globulin, alpha-fetoprotein, and the ratios of estradiols to testosterones were compared between the case and control mothers. The results found no significant differences in the levels of testosterone (total, free, bioavailable), alpha-fetoprotein, sex hormone-binding globulin, or in the ratios of estrogens to androgens. Total estradiol, however, was significantly lower in the cases versus the controls (P = 0.03) among all mothers and, separately, among White mothers (P = 0.05). Similarly, estriol was significantly lower among all cases (P = 0.05) and among White cases (P = 0.05). These results do not support either the estrogen or the androgen hypothesis. Rather, lower estrogens in case mothers may indicate that a placental defect increases the risk of cryptorchism and, possibly, testicular cancer.

Cowbird removals unexpectedly increase productivity of a brood parasite and the songbird host.

PubMed

Kosciuch, Karl L; Sandercock, Brett K

2008-03-01

Generalist brood parasites reduce productivity and population growth of avian hosts and have been implicated in population declines of several songbirds of conservation concern. To estimate the demographic effects of brood parasitism on Bell's Vireos (Vireo bellii), we removed Brown-headed Cowbirds (Molothrus ater) in a replicated switchback experimental design. Cowbird removals decreased parasitism frequency from 77% and 85% at unmanipulated plots to 58% and 47% at removal plots in 2004 and 2005, respectively. Vireo productivity per pair was higher at cowbird removal plots when years were pooled (mean = 2.6 +/- 0.2 [SE] young per pair) compared to unmanipulated plots (1.2 +/- 0.1). Nest desertion frequency was lower at cowbird removal plots (35% of parasitized nests) compared to unmanipulated plots (69%) because removal of host eggs was the proximate cue for nest desertion, and vireos experienced lower rates of egg loss at cowbird removal plots. Nest success was higher among unparasitized than parasitized nests, and parasitized nests at cowbird removal plots had a higher probability of success than parasitized nests at unmanipulated plots. Unexpectedly, cowbird productivity from vireo pairs was higher at cowbird removal plots (mean = 0.3 +/- 0.06 young per pair) than at unmanipulated plots (0.1 +/- 0.03) because fewer parasitized nests were deserted and the probability of nest success was higher. Our study provides the first evidence that increases in cowbird productivity may be an unintended consequence of cowbird control programs, especially during the initial years of trapping when parasitism may only be moderately reduced. Thus, understanding the demographic impacts of cowbird removals requires an informed understanding of the behavioral ecology of host-parasite interactions.

Improving coeliac disease risk prediction by testing non-HLA variants additional to HLA variants.

PubMed

Romanos, Jihane; Rosén, Anna; Kumar, Vinod; Trynka, Gosia; Franke, Lude; Szperl, Agata; Gutierrez-Achury, Javier; van Diemen, Cleo C; Kanninga, Roan; Jankipersadsing, Soesma A; Steck, Andrea; Eisenbarth, Georges; van Heel, David A; Cukrowska, Bozena; Bruno, Valentina; Mazzilli, Maria Cristina; Núñez, Concepcion; Bilbao, Jose Ramon; Mearin, M Luisa; Barisani, Donatella; Rewers, Marian; Norris, Jill M; Ivarsson, Anneli; Boezen, H Marieke; Liu, Edwin; Wijmenga, Cisca

2014-03-01

The majority of coeliac disease (CD) patients are not being properly diagnosed and therefore remain untreated, leading to a greater risk of developing CD-associated complications. The major genetic risk heterodimer, HLA-DQ2 and DQ8, is already used clinically to help exclude disease. However, approximately 40% of the population carry these alleles and the majority never develop CD. We explored whether CD risk prediction can be improved by adding non-HLA-susceptible variants to common HLA testing. We developed an average weighted genetic risk score with 10, 26 and 57 single nucleotide polymorphisms (SNP) in 2675 cases and 2815 controls and assessed the improvement in risk prediction provided by the non-HLA SNP. Moreover, we assessed the transferability of the genetic risk model with 26 non-HLA variants to a nested case-control population (n=1709) and a prospective cohort (n=1245) and then tested how well this model predicted CD outcome for 985 independent individuals. Adding 57 non-HLA variants to HLA testing showed a statistically significant improvement compared to scores from models based on HLA only, HLA plus 10 SNP and HLA plus 26 SNP. With 57 non-HLA variants, the area under the receiver operator characteristic curve reached 0.854 compared to 0.823 for HLA only, and 11.1% of individuals were reclassified to a more accurate risk group. We show that the risk model with HLA plus 26 SNP is useful in independent populations. Predicting risk with 57 additional non-HLA variants improved the identification of potential CD patients. This demonstrates a possible role for combined HLA and non-HLA genetic testing in diagnostic work for CD.

Determinants of stingless bee nest density in lowland dipterocarp forests of Sabah, Malaysia.

PubMed

Eltz, Thomas; Brühl, Carsten A; van der Kaars, Sander; Linsenmair, Eduard K

2002-03-01

We measured the nest density of stingless bees (Apidae, Meliponini) in undisturbed and logged-over dipterocarp forests in Sabah, northern Borneo, and evaluated hypotheses on proximate factors leading to the observed variation: population control mediated by (1) nest predation, (2) limitation of nest trees, or (3) food limitation. Per-area nest density varied twentyfold across 14 forest sites and was significantly affected by locality, but not by the degree and history of disturbance. Nest density was generally high in sites located in the Sepilok Forest fragment (mean 8.4 nests/ha), bordering mangroves or plantations. In contrast, nest densities in continuous forests were all low (between 0 and 2.1 nests/ha, mean 0.5 nests/ha). Yearly nest mortality was low (13.5-15.0%) over 4 years of observation and did not vary between forest localities, thus limiting the potential of nest predation (1) in creating the observed variation in nest density. The presence of potential nest trees (2), though positively correlated with nest density, explained only a minute fraction of the observed variation. Nest density was best explained by differences in the pollen resources (3) available to the bees (quantified by analysis of pollen in bee garbage). Across five selected sites the amount of nonforest pollen (from mangrove or crop plants) included in diets of Trigona collina was positively correlated with T. collina nest density. External pollen sources are a likely supplement to bee diets at times when little flowering occurs inside the forest, thus increasing overall bee carrying capacity. Pollen limitation was also indicated by direct measurements of pollen import and foraging activity of T. collina in three selected sites: Pollen traps installed at nests in high-density Sepilok captured significantly more corbicular pollen than colonies in low-density Deramakot. At the same time, morning foraging activity was also greater in Sepilok, indicating a regulatory increase in foraging in response to high pollen availability. We conclude that the abundance of stingless bees in forests in Sabah is chiefly dependent on the local availability of food resources. Bee populations strongly benefit from edge effects and increased foraging habitat diversity. Electronic supplementary material to this paper can be obtained by using the Springer Link server located at http://dx.doi.org/10.1007/s00442-001-0848-6.

Application of STR markers in wildlife forensic casework involving Australian black-cockatoos (Calyptorhynchus spp.).

PubMed

White, Nicole E; Dawson, Rick; Coghlan, Megan L; Tridico, Silvana R; Mawson, Peter R; Haile, James; Bunce, Michael

2012-09-01

Parrots and cockatoos are highly prized aviary birds and the demands for such species has fuelled their illegal trade and harvest from the wild. Here we report on three forensic case studies involving black-cockatoos (Calyptorhynchus spp.) endemic to Australia. These cases involve suspected poaching and illegal killing of endangered red- and white-tailed black-cockatoos. Through the prior development of 20 polymorphic microsatellite loci and population databases for white- and red-tailed black-cockatoos, the tools are available to conduct high-resolution paternity and individual identity testing. In one case, we matched a red-tailed black-cockatoo nestling to a tree hollow from which it was poached through the use of DNA from eggshell recovered from the nest. For the second case, we utilized our provenance population database (nest sites), and identified the kinship and geographic origin of a white-tailed black-cockatoo, which was illegally harvested from the wild. The third case determined the number individual white-tailed black-cockatoos allegedly shot at a fruit grower's orchard from body part remains. These genetic investigations highlight the significance and statistical confidence of DNA profiling and associated databases for endangered taxa, such as exotic birds. Our cockatoo population databases are the first of their kind in Australia, and demonstrate the efficacy of such approaches to identify such illegal activity. With a robust set of genetic markers and methodologies in place, we aim to broaden our population databases to include other cockatoo species of conservation concern. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Brood-parasite interactions between great spotted cuckoos and magpies: a model system for studying coevolutionary relationships.

PubMed

Soler, Juan; Soler, Manuel

2000-11-01

Brood parasitism is one of the systems where coevolutionary processes have received the most research. Here, we review experiments that suggest a coevolutionary process between the great spotted cuckoo (Clamator glandarius) and its magpie (Pica pica) host. We focus on different stages of establishment of the relationship, from cuckoos selecting individual hosts and hosts defending their nests from adult cuckoos, to the ability of magpies to detect cuckoo eggs in their nests. Novel coevolutionary insights emerge from our synthesis of the literature, including how the evolution of "Mafia" behaviour in cuckoos does not necessarily inhibit the evolution of host recognition and rejection of cuckoo offspring, and how different populations of black-billed magpies in Europe have evolved specific host traits (e.g. nest and clutch size) as a result of interactions with the great spotted cuckoo. Finally, the results of the synthesis reveal the importance of using a meta-population approach when studying coevolution. This is especially relevant in those cases where gene flow among populations with different degrees of brood parasitism explains patterns of coexistence between defensive and non-defensive host phenotypes. We propose the use of a meta-population approach to distinguish between the "evolutionary equilibrium" hypothesis and the "evolutionary lag" hypothesis.

Nest-site selection, reproductive ecology and shifts within core-use areas of Black-necked Cranes at the northern limit of the Tibetan Plateau

PubMed Central

An, Bei; Shu, Meilin

2017-01-01

We investigated population dynamics, breeding pairs, breeding habitat selection, nest density, distance between neighboring nests, nest survival, reproductive success, and recruitment rate for Black-necked Cranes (BNC, Grus nigricollis) during 2013–2015 in Yanchiwan National Nature Reserve (YCW), Gansu, China. Numbers of BNC and breeding pairs remained relatively stable at around 140 individuals and 40 pairs. Recruitment rates ranged from 15.7% to 25.8%. The average nest distance was 718.66 ± 430.50 m (2013), 1064.51 ± 323.99 m (2014) and 534.99 ± 195.45 m (2015). Average nest survival rate, hatching success, and breeding success of all 29 nests were 65.56 ± 5.09%, 57.04 ± 6.12% and 32.78% ± 2.55. Water depth, water body area, and distance to land were positively related to nest survival, while disturbance level showed a negative relationship. However, nest site selection of BNC was determined by habitat type, disturbance and water depth. BNC often foraged in mudflats and freshwater marsh but seldom foraged in saline-alkali wet meadows due to food density and quantity in April, the month when BNC choose nest sites. Conservation strategies based on habitats should consider ecological factors that may not be well predicted by nest site selection. Shifts within core-use areas from satellite tracking of BNC demonstrated that maintaining populations demands that conservation areas are large enough to permit breeding BNC changes in space use. Our results are important for conservation management and provide quantitative reproductive data for this species. PMID:28168110

Nest-site selection, reproductive ecology and shifts within core-use areas of Black-necked Cranes at the northern limit of the Tibetan Plateau.

PubMed

Zhang, Lixun; An, Bei; Shu, Meilin; Yang, Xiaojun

2017-01-01

We investigated population dynamics, breeding pairs, breeding habitat selection, nest density, distance between neighboring nests, nest survival, reproductive success, and recruitment rate for Black-necked Cranes (BNC, Grus nigricollis ) during 2013-2015 in Yanchiwan National Nature Reserve (YCW), Gansu, China. Numbers of BNC and breeding pairs remained relatively stable at around 140 individuals and 40 pairs. Recruitment rates ranged from 15.7% to 25.8%. The average nest distance was 718.66 ± 430.50 m (2013), 1064.51 ± 323.99 m (2014) and 534.99 ± 195.45 m (2015). Average nest survival rate, hatching success, and breeding success of all 29 nests were 65.56 ± 5.09%, 57.04 ± 6.12% and 32.78% ± 2.55. Water depth, water body area, and distance to land were positively related to nest survival, while disturbance level showed a negative relationship. However, nest site selection of BNC was determined by habitat type, disturbance and water depth. BNC often foraged in mudflats and freshwater marsh but seldom foraged in saline-alkali wet meadows due to food density and quantity in April, the month when BNC choose nest sites. Conservation strategies based on habitats should consider ecological factors that may not be well predicted by nest site selection. Shifts within core-use areas from satellite tracking of BNC demonstrated that maintaining populations demands that conservation areas are large enough to permit breeding BNC changes in space use. Our results are important for conservation management and provide quantitative reproductive data for this species.

Nest and chick survival and colony-site dynamics of least terns in the U.S. Virgin Islands

USGS Publications Warehouse

Lombard, Claudia D.; Collazo, Jaime; McNair, Douglas B.

2010-01-01

We report nest and chick survival and colony-site dynamics of the Least Tern (Sternula antillarum). These results are the first for the Caribbean and were derived with likelihood-based approaches from 4640 nests and 44 chicks fitted with transmitters monitored in 52 colonies at St. Croix, U.S. Virgin Islands, 2003–2006. Managed colonies excluded, overall daily nest survival (±SE) was 0.92 ± 0.03 (period survival = 0.18). Daily nest survival of managed colonies (fenced) was significantly higher (0.97 ± 0.02; period survival = 0.51). Variation in nest survival was best explained by a negative linear trend in daily survival, influenced by year, rain, large colony size, and nesting habitat. Daily nest-survival rates at sandy beaches (0.94 ± 0.02), offshore cays (0.93 ± 0.005), and saltflats (0.91 ± 0.02) did not differ significantly. The period survival of chicks was 0.30 ± 0.11. Estimated fledglings per nest attempt were 0.06. Demographic assessments suggested that higher reproductive rates are required for maintenance (λ ≥ 1). Managed colonies could meet nest-survival thresholds, but complementary measures are needed to increase chick survival. Our findings suggest that management should target sites harboring large colonies because they had higher nest success and higher probability of use in subsequent seasons. The colonies' site dynamics suggested that immigration from other populations is plausible. This possibility relaxes breeding-productivity thresholds and advocates for coordinated conservation among populations on neighboring islands. Estimates of age-specific survival and connectivity are needed for the status of the species to be assessed appropriately and conservation priorities set.

Weather radar data correlate to hail-induced mortality in grassland birds

USGS Publications Warehouse

Carver, Amber; Ross, Jeremy D.; Augustine, David J.; Skagen, Susan K.; Dwyer, Angela M.; Tomback, Diana F.; Wunder, Michael B.

2017-01-01

Small-bodied terrestrial animals such as songbirds (Order Passeriformes) are especially vulnerable to hail-induced mortality; yet, hail events are challenging to predict, and they often occur in locations where populations are not being studied. Focusing on nesting grassland songbirds, we demonstrate a novel approach to estimate hail-induced mortality. We quantify the relationship between the probability of nests destroyed by hail and measured Level-III Next Generation Radar (NEXRAD) data, including atmospheric base reflectivity, maximum estimated size of hail and maximum estimated azimuthal wind shear. On 22 June 2014, a hailstorm in northern Colorado destroyed 102 out of 203 known nests within our research site. Lark bunting (Calamospiza melanocorys) nests comprised most of the sample (n = 186). Destroyed nests were more likely to be found in areas of higher storm intensity, and distributions of NEXRAD variables differed between failed and surviving nests. For 133 ground nests where nest-site vegetation was measured, we examined the ameliorative influence of woody vegetation, nest cover and vegetation density by comparing results for 13 different logistic regression models incorporating the independent and additive effects of weather and vegetation variables. The most parsimonious model used only the interactive effect of hail size and wind shear to predict the probability of nest survival, and the data provided no support for any of the models without this predictor. We conclude that vegetation structure may not mitigate mortality from severe hailstorms and that weather radar products can be used remotely to estimate potential for hail mortality of nesting grassland birds. These insights will improve the efficacy of grassland bird population models under predicted climate change scenarios.

Managing Algorithmic Skeleton Nesting Requirements in Realistic Image Processing Applications: The Case of the SKiPPER-II Parallel Programming Environment's Operating Model

NASA Astrophysics Data System (ADS)

Coudarcher, Rémi; Duculty, Florent; Serot, Jocelyn; Jurie, Frédéric; Derutin, Jean-Pierre; Dhome, Michel

2005-12-01

SKiPPER is a SKeleton-based Parallel Programming EnviRonment being developed since 1996 and running at LASMEA Laboratory, the Blaise-Pascal University, France. The main goal of the project was to demonstrate the applicability of skeleton-based parallel programming techniques to the fast prototyping of reactive vision applications. This paper deals with the special features embedded in the latest version of the project: algorithmic skeleton nesting capabilities and a fully dynamic operating model. Throughout the case study of a complete and realistic image processing application, in which we have pointed out the requirement for skeleton nesting, we are presenting the operating model of this feature. The work described here is one of the few reported experiments showing the application of skeleton nesting facilities for the parallelisation of a realistic application, especially in the area of image processing. The image processing application we have chosen is a 3D face-tracking algorithm from appearance.

Climate and predation dominate juvenile and adult recruitment in a turtle with temperature-dependent sex determination.

PubMed

Schwanz, Lisa E; Spencer, Ricky-John; Bowden, Rachel M; Janzen, Fredric J

2010-10-01

Conditions experienced early in life can influence phenotypes in ecologically important ways, as exemplified by organisms with environmental sex determination. For organisms with temperature-dependent sex determination (TSD), variation in nest temperatures induces phenotypic variation that could impact population growth rates. In environments that vary over space and time, how does this variation influence key demographic parameters (cohort sex ratio and hatchling recruitment) in early life stages of populations exhibiting TSD? We leverage a 17-year data set on a population of painted turtles, Chrysemys picta, to investigate how spatial variation in nest vegetation cover and temporal variation in climate influence early life-history demography. We found that spatial variation in nest cover strongly influenced nest temperature and sex ratio, but was not correlated with clutch size, nest predation, total nest failure, or hatching success. Temporal variation in climate influenced percentage of total nest failure and cohort sex ratio, but not depredation rate, mean clutch size, or mean hatching success. Total hatchling recruitment in a year was influenced primarily by temporal variation in climate-independent factors, number of nests constructed, and depredation rate. Recruitment of female hatchlings was determined by stochastic variation in nest depredation and annual climate and also by the total nest production. Overall population demography depends more strongly on annual variation in climate and predation than it does on the intricacies of nest-specific biology. Finally, we demonstrate that recruitment of female hatchlings translates into recruitment of breeding females into the population, thus linking climate (and other) effects on early life stages to adult demographics.

Heart Disease, Hypertension, Gestational Diabetes Mellitus, and Preeclampsia/Eclampsia in Mothers With Juvenile Arthritis: A Nested Case-Control Study.

PubMed

Feldman, Debbie E; Vinet, Évelyne; Bérard, Anick; Duffy, Ciarán; Hazel, Beth; Meshefedjian, Garbis; Sylvestre, Marie-Pierre; Bernatsky, Sasha

2017-02-01

To determine whether women with a history of juvenile arthritis are at higher risk for heart disease and hypertension and for developing adverse maternal outcomes: gestational diabetes mellitus, maternal hypertension, and preeclampsia/eclampsia. We designed a nested case-control study from a cohort of first-time mothers with prior physician billing codes suggesting juvenile arthritis, and a matched comparison group without juvenile arthritis. For the nested case-control design, we selected 3 controls for each case for the outcomes of heart disease (n = 403), prepregnancy hypertension (n = 66), gestational diabetes mellitus (n = 285), maternal hypertension (n = 561), and preeclampsia/eclampsia (n = 236). We used conditional logistic regression, adjusting for maternal age and education. Having juvenile arthritis was associated with heart disease (odds ratio [OR] 2.44 [95% confidence interval (95% CI) 1.15-5.15]) but not with gestational hypertension, diabetes mellitus, or preeclampsia/eclampsia. All 66 cases of prepregnancy hypertension had juvenile arthritis. Having prepregnancy hypertension was strongly associated with preeclampsia/eclampsia (OR 8.05 [95% CI 2.69-24.07]). Women with a history of juvenile arthritis had a higher risk of heart disease. This risk signals the potential importance of cardiac prevention strategies in juvenile arthritis. As this was a retrospective study, it was not possible to correct for some relevant potential confounders. Further studies should assess the impact of medications, disease severity, and other factors (e.g., obesity) on cardiac outcomes in juvenile arthritis. © 2016, American College of Rheumatology.

Mix-infection of S. Typhi and ParaTyphi A in Typhoid Fever and Chronic Typhoid Carriers: A Nested PCR Based Study in North India

PubMed Central

Pratap, Chandra Bhan; Kumar, Gopal; Patel, Saurabh Kumar; Shukla, Vijay K; Kumar, Kailash; Singh, Tej Bali

2014-01-01

Introduction: Enteric fever is a systemic disease caused by Salmonella organism such as serotypes Typhi and ParaTyphi A, B, C. Salmonella ParaTyphi A contributes more than 50% of all the enteric fever cases and it has recently been projected as an emerging pathogen. Materials and Methods: The present study was aimed to detect Salmonella Typhi and ParaTyphi A in urine, blood and stool specimens collected from cases of enteric fever (110), chronic typhoid carriers (46) and healthy controls (75) to explore the possibility of mixed infection by nested PCR. A new nested PCR primer was designed targeting putative fimbrial protein (stkG) gene which is one of the fimbrial gene families to Salmonella ParaTyphi A and for S. Typhi already reported primers targeting flagellin (fliC) gene. Results: Large volume of urine specimens (15 ml) was found to be the best for detection of Salmonella serotypes. The urine sample was found to have mixed-infection by both the serotypes in 40.9% of the cases but lower in blood (27.3%) and stool (13.6%). Conclusion: The present study concludes that occurrence of mixed infection may be quite frequent in typhoid and chronic typhoid carriers’ individuals, although the reported recent rise in ParaTyphi A incidence may not be real. PMID:25584217

Effectiveness of quadrivalent human papillomavirus vaccine for the prevention of cervical abnormalities: case-control study nested within a population based screening programme in Australia.

PubMed

Crowe, Elizabeth; Pandeya, Nirmala; Brotherton, Julia M L; Dobson, Annette J; Kisely, Stephen; Lambert, Stephen B; Whiteman, David C

2014-03-04

To measure the effectiveness of the quadrivalent human papillomavirus (HPV) vaccine against cervical abnormalities four years after implementation of a nationally funded vaccination programme in Queensland, Australia. Case-control analysis of linked administrative health datasets. Queensland, Australia. Women eligible for free vaccination (aged 12-26 years in 2007) and attending for their first cervical smear test between April 2007 and March 2011. High grade cases were women with histologically confirmed high grade cervical abnormalities (n = 1062) and "other cases" were women with any other abnormality at cytology or histology (n = 10,887). Controls were women with normal cytology (n = 96,404). Exposure odds ratio (ratio of odds of antecedent vaccination (one, two, or three vaccine doses compared with no doses) among cases compared with controls), vaccine effectiveness ((1-adjusted odds ratio) × 100), and number needed to vaccinate to prevent one cervical abnormality at first screening round. We stratified by four age groups adjusted for follow-up time, year of birth, and measures of socioeconomic status and remoteness. The primary analysis concerned women whose first ever smear test defined their status as a case or a control. The adjusted odds ratio for exposure to three doses of HPV vaccine compared with no vaccine was 0.54 (95% confidence interval 0.43 to 0.67) for high grade cases and 0.66 (0.62 to 0.70) for other cases compared with controls with normal cytology, equating to vaccine effectiveness of 46% and 34%, respectively. The adjusted numbers needed to vaccinate were 125 (95% confidence interval 97 to 174) and 22 (19 to 25), respectively. The adjusted exposure odds ratios for two vaccine doses were 0.79 (95% confidence interval 0.64 to 0.98) for high grade cases and 0.79 (0.74 to 0.85) for other cases, equating to vaccine effectiveness of 21%. The quadrivalent HPV vaccine conferred statistically significant protection against cervical abnormalities in young women who had not started screening before the implementation of the vaccination programme in Queensland, Australia.

The Diagnostic Utility of Bact/ALERT and Nested PCR in the Diagnosis of Tuberculous Meningitis.

PubMed

Sastry, Apurba Sankar; Bhat K, Sandhya; Kumudavathi

2013-01-01

The early laboratory diagnosis of Tuberculous Meningitis (TBM) is crucial, to start the antitubercular chemotherapy and to prevent its complications. However, the conventional methods are either less sensitive or time consuming. Hence, the diagnostic potentials of BacT/ALERT and Polymerase Chain Reaction (PCR) was evaluated in this study. The study group comprised of 62 cases and 33 controls. The cases were divided according to Ahuja's criteria into the confirmed (two cases), highly probable (19 cases), probable (26 cases) and the possible (15 cases) subgroups. Ziehl Neelsen's (ZN) and Auramine Phenol (AP) staining, Lowenstein Jensen (LJ) medium culture, BacT/ALERT and nested Polymerase Chain Reaction (PCR) which targeted IS6110 were carried out on all the patients. The sensitivity of the LJ culture was 3.22%. BacT/ALERT showed a sensitivity and a specificity of 25.80% and 100% and those of nested PCR were found to be 40.32% and 96.97% respectively. The mean detection time of growth of the LJ culture was 31.28 days, whereas that of BacT/ALERT was 20.68 days. The contamination rate in the LJ culture and BacT/ALERT were 7.2% and 5.8% respectively. Nested PCR was found to be more sensitive, followed by BacT/ALERT as compared to the LJ culture and smear microscopy. As both false negative and false positive results have been reported for nested PCR, so it should not be used alone as a criterion for initiating or terminating the therapy, but it should be supported by clinical, radiological, cytological and other microbiological findings.

Bridging the etiologic and prognostic outlooks in individualized assessment of absolute risk of an illness: application in lung cancer.

PubMed

Karp, Igor; Sylvestre, Marie-Pierre; Abrahamowicz, Michal; Leffondré, Karen; Siemiatycki, Jack

2016-11-01

Assessment of individual risk of illness is an important activity in preventive medicine. Development of risk-assessment models has heretofore relied predominantly on studies involving follow-up of cohort-type populations, while case-control studies have generally been considered unfit for this purpose. To present a method for individualized assessment of absolute risk of an illness (as illustrated by lung cancer) based on data from a 'non-nested' case-control study. We used data from a case-control study conducted in Montreal, Canada in 1996-2001. Individuals diagnosed with lung cancer (n = 920) and age- and sex-matched lung-cancer-free subjects (n = 1288) completed questionnaires documenting life-time cigarette-smoking history and occupational, medical, and family history. Unweighted and weighted logistic models were fitted. Model overfitting was assessed using bootstrap-based cross-validation and 'shrinkage.' The discriminating ability was assessed by the c-statistic, and the risk-stratifying performance was assessed by examination of the variability in risk estimates over hypothetical risk-profiles. In the logistic models, the logarithm of incidence-density of lung cancer was expressed as a function of age, sex, cigarette-smoking history, history of respiratory conditions and exposure to occupational carcinogens, and family history of lung cancer. The models entailed a minimal degree of overfitting ('shrinkage' factor: 0.97 for both unweighted and weighted models) and moderately high discriminating ability (c-statistic: 0.82 for the unweighted model and 0.66 for the weighted model). The method's risk-stratifying performance was quite high. The presented method allows for individualized assessment of risk of lung cancer and can be used for development of risk-assessment models for other illnesses.

High duck nesting success in a predator-reduced environment

USGS Publications Warehouse

Duebbert, H.F.; Lokemoen, J.T.

1980-01-01

Duck nesting and production were studied during 1969-74 on a 51-ha field of undisturbed grass-legume cover and a surrounding 8.13-km2 area in north-central South Dakota. The principal mammalian predators of ducks were reduced within a 259-km2 zone from May 1969 through August 1971. Dabbling duck nest densities, hatching success, and breeding populations attained high levels. Seven duck species produced 1,062 nests on the 51-ha field during 6 years, 864 (81%) hatched, 146 (14%) were destroyed, and 52 (5%) had other fates. During 1970-72, when predator reduction was most effective, the hatching success for 756 nests was 94%. The number of mallard (Anas platyrhynchos) nests increased from 37 (0.7/ha) in 1969 to 181 (3.5/ha) in 1972. Mallard pairs increased from 2.8/km2 to 16.8/km2 on the 8.13-km2 area during the same period. A minimum of 7,250 ducklings hatched on the 51-ha field during the 6 years, including 2,342 ducklings in 1972. Exceptionally high duck nesting densities and hatching rates occurred when predators were controlled.

Factors influencing nesting success of burrowing owls in southeastern Idaho

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gleason, R.S.; Johnson, D.R.

1985-01-31

A burrowing owl (Athene cunicularia) population nesting on the Idaho National Engineering Laboratory (INEL) in southeastern Idaho utilized burrows excavated by badgers (Taxidea taxus) or natural cavities in lava flows as nesting sites. The size of the population was small (N = 13-14 pairs) in relation to the number of available nesting sites, suggesting that factors other than burrow availability limited this population. Rodents and Jerusalem crickets (Stenopelmatus fuscus) represented the primary prey utilized during the nesting season. This population demonstrated both a numerical (brood size) and functional (dietary) response to a decrease in the density of three species ofmore » rodents on the INEL during a drought in 1977. 11 references, 1 figure, 2 table.« less

The implications of variable remigration intervals for the assessment of population size in marine turtles.

PubMed

Hays, G C

2000-09-21

Sea turtles nest on sandy beaches and tend to show high fidelity to specific nesting areas, but, despite this fidelity, the inter-annual variation in nesting numbers may be large. This variation may reflect the fact that turtles do not usually nest in consecutive years. Here, theoretical models are developed in which the interval between successive nesting years (the remigration interval) reflects conditions encountered on the feeding grounds, with good feeding years leading to a reduction in the remigration interval and vice versa. These simple models produce high levels of inter-annual variation in nesting numbers with, on occasion, almost no turtles nesting in some years even when the population is large and stable. The implications for assessing the size of sea turtle populations are considered. Copyright 2000 Academic Press.

The common redstart as a suitable model to study cuckoo-host coevolution in a unique ecological context.

PubMed

Samaš, Peter; Rutila, Jarkko; Grim, Tomáš

2016-11-25

Co-evolutionary arms-races result in spatio-temporally dynamic relationships between interacting species, e.g., brood parasites and their avian hosts. However, majority of avian co-evolutionary studies are limited to "snap-shots" of a single breeding season in an open-nesting host. In a long-term study (11 breeding seasons), we explored a unique system between the brood parasitic common cuckoo (Cuculus canorus) and its host, the common redstart (Phoenicurus phoenicurus) which is exceptional among all cuckoo hosts due to being a cavity nester. Conditions in cavities are different from open nests, e.g., lower risks of predation, more favourable microclimate, increased risks of unsuccessful eviction of host offspring by the cuckoo nestling. Different conditions in cavities thus can be expected to shape parasite-host coevolution differently from what is typically studied in open nesting hosts. In our highly parasitised nest-box population (32.5%, n = 569 nests) only 35.7% of cuckoo eggs were laid into the nest cup and incubated by redstarts. Host nests shifted availability to later into the breeding season from 2006 to 2016 and cuckoos followed this trend by also shifting their timing of parasitism. Although previous studies revealed that redstarts selectively eject experimental non-mimetic eggs (desertion was not a specific response to foreign eggs), the hosts never ejected naturally-laid cuckoo eggs or cuckoo eggs cross-fostered into naturally non-parasitised nests. We solve the long-standing debate about the origin of cuckoo eggs found on the nest rim: we gained the first direct video-recording evidence that eggs found on the nest rim were mislaid by parasites and not ejected by hosts. Naturally-parasitised nests were deserted more often (18.6%) than control non-parasitized nests (5.6%) or nests artificially parasitised by us (1.4%). This suggests that the sight of the laying cuckoo female is the primary cue that triggers egg rejection (by desertion) in this host. Review of data from this and other study sites (10 populations, n = 853 experiments) demonstrates high variability in rejection rates and shows that populations facing higher parasitism rates reject parasitic eggs with higher frequencies. Surprisingly, cuckoo chicks either growing solitarily or with redstart chicks did not differ in their fledging success. We suggest that the redstart is an ideal model system to study the flexibility and limits of brood parasite-host co-evolution in an extreme ecological setting.

[Demography and nesting ecology of green iguana, Iguana iguana (Squamata: Iguanidae), in 2 exploited populations in Depresión Momposina, Colombia].

PubMed

Muñoz, Eliana M; Ortega, Angela M; Bock, Brian C; Páez, Vivian P

2003-03-01

We studied the demography and nesting ecology of two populations of Iguana iguana that face heavy exploitation and habitat modification in the Momposina Depression, Colombia. Lineal transect data was analyzed using the Fourier model to provide estimates of social group densities, which was found to differ both within and among populations (1.05-6.0 groups/ha). Mean group size and overall iguana density estimates varied between populations as well (1.5-13.7 iguanas/ha). The density estimates were far lower than those reported from more protected areas in Panama and Venezuela. Iguana densities were consistently higher in sites located along rivers (2.5 iguanas/group) than in sites along the margin of marshes, probably due to vegetational differences (1.5 iguanas/group). There was no correlation between density estimates and estimates of relative abundance (number of iguanas seen/hour/person) due to differing detectabilities of iguana groups among sites. The adult sex ratio (1:2.5 males:females) agreed well with other reports in the literature based upon observation of adult social groups, and probably results from the polygynous mating system in this species rather than a real demographic skew. Nesting in this population occurs from the end of January through March and hatching occurs between April and May. We monitored 34 nests, which suffered little vertebrate predation, perhaps due to the lack of a complete vertebrate fauna in this densely inhabited area, but nests suffered from inundation, cattle trampling, and infestation by phorid fly larvae. Clutch sizes in these populations were lower than all other published reports except for the iguana population on the highly xeric island of Curaçao, implying that adult females in our area are unusually small. We argue that this is more likely the result of the exploitation of these populations rather than an adaptive response to environmentally extreme conditions.

Integrating biology into invasive species management is a key principle for eradication success: the case of yellow crazy ant Anoplolepis gracilipes in northern Australia.

PubMed

Hoffmann, B D

2015-04-01

The lack of biological knowledge of many invasive species remains as one of the greatest impediments to their management. Here I detail targeted research into the biology of the yellow crazy ant Anoplolepis gracilipes within northern Australia and detail how such knowledge can be used to improve the management outcomes for this species. I quantified nest location and density in three habitats, worker activity over 24 h, infestation expansion rate, seasonal variation of worker abundance and the timing of production of sexuals. Nests were predominantly (up to 68%) located at the bases of large trees, indicating that search efforts should focus around tree bases. Nest density was one nest per 22, 7.1 and 6.3 m2 in the three habitats, respectively. These data form the baselines for quantifying treatment efficacy and set sampling densities for post-treatment assessments. Most (60%) nests were underground, predominantly (89%) occurring in an open area rather than underneath a rock or log. Some seasonality was evident for nests within leaf litter, with most (83%) occurring during the 'wet season' (October-March). Of the underground nests, most were shallow, with 44% being less than 10 cm deep, and 67% being less than 20 cm deep. Such nest location and density information serves many management purposes, for improving detection, mapping and post-treatment assessments, and also provided strong evidence that carbohydrate supply was a major driver of A. gracilipes populations. Just over half of the nests (56%) contained queens. Of the 62 underground nests containing queens, most queens (80%) were located at the deepest chamber. When queens were present, most often (38%) only one queen was present, the most being 16. Queen number per nest was the lowest in July and August just prior to the emergence of virgin queens in September, with queen numbers then remaining steadily high until April. Nothing is known for any ant species about how the queen number per nest/colony affects treatment efficacy, but further research would no doubt yield important breakthroughs for treating ants. Activity occurred predominantly nocturnally, ceasing during mid-day. These activity data determined the critical threshold above which work must be conducted to be considered reliable, and also suggests that treatments are best applied in the afternoon. Total brood production peaked in February and was the lowest around August and September. These abundance data form the baselines for quantifying treatment efficacy, and may have implications for treatment efficacy. Males were found every month, predominantly between August and November. Queen pupae were found in September. The reproductive timing of sexuals determines the treatment schedule. Targeted, site-specific research such as that described here should be an integral part of any eradication program for invasive species to design knowledge-based treatment protocols and determine assessment benchmarks.

Chapter 7: Breeding and Natal Dispersal, Nest Habitat Loss and Implications for Marbled Murrelet Populations

Treesearch

George J. Divoky; Michael Horton

1995-01-01

Evidence of breeding and natal dispersal in alcids is typically provided by the resightings of banded birds, the establishment of new colonies, and/or evidence of immigration to established colonies. The difficulties in banding, observing, and censusing Marbled Murrelets at nesting areas preclude using any of these methods for this species. Based on the limited number...

Projected response of an endangered marine turtle population to climate change

NASA Astrophysics Data System (ADS)

Saba, Vincent S.; Stock, Charles A.; Spotila, James R.; Paladino, Frank V.; Tomillo, Pilar Santidrián

2012-11-01

Assessing the potential impacts of climate change on individual species and populations is essential for the stewardship of ecosystems and biodiversity. Critically endangered leatherback turtles in the eastern Pacific Ocean are excellent candidates for such an assessment because their sensitivity to contemporary climate variability has been substantially studied. If incidental fisheries mortality is eliminated, this population still faces the challenge of recovery in a rapidly changing climate. Here we combined an Earth system model, climate model projections assessed by the Intergovernmental Panel on Climate Change and a population dynamics model to estimate a 7% per decade decline in the Costa Rica nesting population over the twenty-first century. Whereas changes in ocean conditions had a small effect on the population, the ~2.5°C warming of the nesting beach was the primary driver of the decline through reduced hatching success and hatchling emergence rate. Hatchling sex ratio did not substantially change. Adjusting nesting phenology or changing nesting sites may not entirely prevent the decline, but could offset the decline rate. However, if future observations show a long-term decline in hatching success and emergence rate, anthropogenic climate mitigation of nests (for example, shading, irrigation) may be able to preserve the nesting population.

Historical versus Contemporary Climate Forcing on the Annual Nesting Variability of Loggerhead Sea Turtles in the Northwest Atlantic Ocean

PubMed Central

Arendt, Michael D.; Schwenter, Jeffrey A.; Witherington, Blair E.; Meylan, Anne B.; Saba, Vincent S.

2013-01-01

A recent analysis suggested that historical climate forcing on the oceanic habitat of neonate sea turtles explained two-thirds of interannual variability in contemporary loggerhead (Caretta caretta) sea turtle nest counts in Florida, where nearly 90% of all nesting by this species in the Northwest Atlantic Ocean occurs. Here, we show that associations between annual nest counts and climate conditions decades prior to nest counts and those conditions one year prior to nest counts were not significantly different. Examination of annual nest count and climate data revealed that statistical artifacts influenced the reported 31-year lag association with nest counts. The projected importance of age 31 neophytes to annual nest counts between 2020 and 2043 was modeled using observed nest counts between 1989 and 2012. Assuming consistent survival rates among cohorts for a 5% population growth trajectory and that one third of the mature female population nests annually, the 41% decline in annual nest counts observed during 1998–2007 was not projected for 2029–2038. This finding suggests that annual nest count trends are more influenced by remigrants than neophytes. Projections under the 5% population growth scenario also suggest that the Peninsular Recovery Unit could attain the demographic recovery criteria of 106,100 annual nests by 2027 if nest counts in 2019 are at least comparable to 2012. Because the first year of life represents only 4% of the time elapsed through age 31, cumulative survival at sea across decades explains most cohort variability, and thus, remigrant population size. Pursuant to the U.S. Endangered Species Act, staggered implementation of protection measures for all loggerhead life stages has taken place since the 1970s. We suggest that the 1998–2007 nesting decline represented a lagged perturbation response to historical anthropogenic impacts, and that subsequent nest count increases since 2008 reflect a potential recovery response. PMID:24339901

Greater sage-grouse nest predators in the Virginia Mountains of northwestern Nevada

USGS Publications Warehouse

Lockyer, Zachary B.; Coates, Peter S.; Casazza, Michael L.; Espinosa, Shawn; Delehanty, David J.

2013-01-01

Greater sage-grouse Centrocercus urophasianus, hereafter sage-grouse, populations have declined across their range due to the loss, degradation, and fragmentation of habitat. Habitat alterations can lead not only to vegetative changes but also to shifts in animal behavior and predator composition that may influence population vital rates, such as nest success. For example, common ravens Corvus corax are sage-grouse nest predators, and common raven abundance is positively associated with human-caused habitat alterations. Because nest success is a central component to sage-grouse population persistence, research that identifies factors influencing nest success will better inform conservation efforts. We used videography to unequivocally identify sage-grouse nest predators within the Virginia Mountains of northwestern Nevada, USA, from 2009 to 2011 and used maximum likelihood to calculate daily probability of nest survival. In the Virginia Mountains, fires, energy exploration, and other anthropogenic activities have altered historic sage-grouse habitat. We monitored 71 sage-grouse nests during the study, placing video cameras at 39 nests. Cumulative nest survival for all nests was 22.4% (95% CI, 13.0–33.4%), a survival rate that was significantly lower than other published results for sage-grouse in the Great Basin. Depredation was the primary cause for nest failure in our study (82.5%), and common ravens were the most frequent sage-grouse nest predator, accounting for 46.7% of nest depredations. We also successfully documented a suite of mammalian and reptilian species depredating sage-grouse nests, including some predators never previously confirmed in the literature to be sage-grouse nest predators (i.e., bobcats Lynx rufus and long-tailed weasels Mephitis frenata). Within the high elevation, disturbed habitat of the Virginia Mountains, low sage-grouse nest success may be limiting sage-grouse population growth. These results suggest that management actions that restore habitat in the Virginia Mountains and decrease anthropogenic subsidies of ravens will benefit sage-grouse.

Historical versus contemporary climate forcing on the annual nesting variability of loggerhead sea turtles in the Northwest Atlantic Ocean.

PubMed

Arendt, Michael D; Schwenter, Jeffrey A; Witherington, Blair E; Meylan, Anne B; Saba, Vincent S

2013-01-01

A recent analysis suggested that historical climate forcing on the oceanic habitat of neonate sea turtles explained two-thirds of interannual variability in contemporary loggerhead (Caretta caretta) sea turtle nest counts in Florida, where nearly 90% of all nesting by this species in the Northwest Atlantic Ocean occurs. Here, we show that associations between annual nest counts and climate conditions decades prior to nest counts and those conditions one year prior to nest counts were not significantly different. Examination of annual nest count and climate data revealed that statistical artifacts influenced the reported 31-year lag association with nest counts. The projected importance of age 31 neophytes to annual nest counts between 2020 and 2043 was modeled using observed nest counts between 1989 and 2012. Assuming consistent survival rates among cohorts for a 5% population growth trajectory and that one third of the mature female population nests annually, the 41% decline in annual nest counts observed during 1998-2007 was not projected for 2029-2038. This finding suggests that annual nest count trends are more influenced by remigrants than neophytes. Projections under the 5% population growth scenario also suggest that the Peninsular Recovery Unit could attain the demographic recovery criteria of 106,100 annual nests by 2027 if nest counts in 2019 are at least comparable to 2012. Because the first year of life represents only 4% of the time elapsed through age 31, cumulative survival at sea across decades explains most cohort variability, and thus, remigrant population size. Pursuant to the U.S. Endangered Species Act, staggered implementation of protection measures for all loggerhead life stages has taken place since the 1970s. We suggest that the 1998-2007 nesting decline represented a lagged perturbation response to historical anthropogenic impacts, and that subsequent nest count increases since 2008 reflect a potential recovery response.

Monitoring bald eagles using lists of nests: Response to Watts and Duerr

USGS Publications Warehouse

Sauer, John R.; Otto, Mark C.; Kendall, William L.; Zimmerman, Guthrie S.

2011-01-01

The post-delisting monitoring plan for bald eagles (Haliaeetus leucocephalus) roposed use of a dual-frame sample design, in which sampling of known nest sites in combination with additional area-based sampling is used to estimate total number of nesting bald eagle pairs. Watts and Duerr (2010) used data from repeated observations of bald eagle nests in Virginia, USA to estimate a nest turnover rate and used this rate to simulate decline in number of occupied nests in list nests over time. Results of Watts and Duerr suggest that, given the rates of loss of nests from the list of known nest sites in Virginia, the list information will be of little value to sampling unless lists are constantly updated. Those authors criticize the plan for not placing sufficient emphasis on updating and maintaining lists of bald eagle nests. Watts and Duerr's metric of turnover rate does not distinguish detectability or temporary nonuse of nests from permanent loss of nests and likely overestimates turnover rate. We describe a multi-state capture–recapture model that allows appropriate estimation of rates of loss of nests, and we use the model to estimate rates of loss from a sample of nests from Maine, USA. The post-delisting monitoring plan addresses the need to maintain and update the lists of nests, and we show that dual frame sampling is an effective approach for sampling nesting bald eagle populations.

Climate Impacts on Sea Turtle Breeding Phenology in Greece and Associated Foraging Habitats in the Wider Mediterranean Region

PubMed Central

Morreale, Stephen J.; Saba, Vincent S.; Panagopoulou, Aliki; Margaritoulis, Dimitris; Spotila, James R.

2016-01-01

Sea turtles are vulnerable to climate change impacts in both their terrestrial (nesting beach) and oceanic habitats. From 1982 to 2012, air and sea surface temperatures at major high use foraging and nesting regions (n = 5) of loggerhead turtles (Caretta caretta) nesting in Greece have steadily increased. Here, we update the established relationships between sea surface temperature and nesting data from Zakynthos (latitude: 37.7°N), a major nesting beach, while also expanding these analyses to include precipitation and air temperature and additional nesting data from two other key beaches in Greece: Kyparissia Bay (latitude: 37.3°N) and Rethymno, Crete (latitude: 35.4°N). We confirmed that nesting phenology at Zakynthos has continued to be impacted by breeding season temperature; however, temperature has no consistent relationship with nest numbers, which are declining on Zakynthos and Crete but increasing at Kyparissia. Then using statistically downscaled outputs of 14 climate models assessed by the Intergovernmental Panel on Climate Change (IPCC), we projected future shifts in nesting for these populations. Based on the climate models, we projected that temperature at the key foraging and breeding sites (Adriatic Sea, Aegean Sea, Crete, Gulf of Gabès and Zakynthos/Kyparissia Bay; overall latitudinal range: 33.0°—45.8°N) for loggerhead turtles nesting in Greece will rise by 3–5°C by 2100. Our calculations indicate that the projected rise in air and ocean temperature at Zakynthos could cause the nesting season in this major rookery to shift to an earlier date by as much as 50–74 days by 2100. Although an earlier onset of the nesting season may provide minor relief for nest success as temperatures rise, the overall climatic changes to the various important habitats will most likely have an overall negative impact on this population. PMID:27332550

Climate Impacts on Sea Turtle Breeding Phenology in Greece and Associated Foraging Habitats in the Wider Mediterranean Region.

PubMed

Patel, Samir H; Morreale, Stephen J; Saba, Vincent S; Panagopoulou, Aliki; Margaritoulis, Dimitris; Spotila, James R

2016-01-01

Sea turtles are vulnerable to climate change impacts in both their terrestrial (nesting beach) and oceanic habitats. From 1982 to 2012, air and sea surface temperatures at major high use foraging and nesting regions (n = 5) of loggerhead turtles (Caretta caretta) nesting in Greece have steadily increased. Here, we update the established relationships between sea surface temperature and nesting data from Zakynthos (latitude: 37.7°N), a major nesting beach, while also expanding these analyses to include precipitation and air temperature and additional nesting data from two other key beaches in Greece: Kyparissia Bay (latitude: 37.3°N) and Rethymno, Crete (latitude: 35.4°N). We confirmed that nesting phenology at Zakynthos has continued to be impacted by breeding season temperature; however, temperature has no consistent relationship with nest numbers, which are declining on Zakynthos and Crete but increasing at Kyparissia. Then using statistically downscaled outputs of 14 climate models assessed by the Intergovernmental Panel on Climate Change (IPCC), we projected future shifts in nesting for these populations. Based on the climate models, we projected that temperature at the key foraging and breeding sites (Adriatic Sea, Aegean Sea, Crete, Gulf of Gabès and Zakynthos/Kyparissia Bay; overall latitudinal range: 33.0°-45.8°N) for loggerhead turtles nesting in Greece will rise by 3-5°C by 2100. Our calculations indicate that the projected rise in air and ocean temperature at Zakynthos could cause the nesting season in this major rookery to shift to an earlier date by as much as 50-74 days by 2100. Although an earlier onset of the nesting season may provide minor relief for nest success as temperatures rise, the overall climatic changes to the various important habitats will most likely have an overall negative impact on this population.

Nest temperatures in a loggerhead nesting beach in Turkey is more determined by sea surface than air temperature.

PubMed

Girondot, Marc; Kaska, Yakup

2015-01-01

While climate change is now fully recognised as a reality, its impact on biodiversity is still not completely understood. To predict its impact, proxies coherent with the studied ecosystem or species are thus required. Marine turtles are threatened worldwide (though some populations are recovering) as they are particularly sensitive to temperature throughout their entire life cycle. This is especially true at the embryo stage when temperature affects both growth rates and sex determination. Nest temperature is thus of prime importance to understand the persistence of populations in the context of climate change. We analysed the nest temperature of 21 loggerheads (Caretta caretta) originating from Dalyan Beach in Turkey using day-lagged generalised mixed models with autocorrelation. Surprisingly, the selected model for nest temperature includes an effect for sea surface temperature 4-times higher than for air temperature. We also detected a very significant effect of metabolic heating during development compatible with what is already known about marine turtle nests. Our new methodology allows the prediction of marine turtle nest temperatures with good precision based on a combination of air temperature measured at beach level and sea surface temperature in front of the beach. These data are available in public databases for most of the beaches worldwide. Copyright © 2014 Elsevier Ltd. All rights reserved.

Changes in reproductive life-history strategies in response to nest density in a shell-brooding cichlid, Telmatochromis vittatus

NASA Astrophysics Data System (ADS)

Ota, Kazutaka; Hori, Michio; Kohda, Masanori

2012-01-01

To determine whether the appearance of a reproductively parasitic tactic varies, and how this variation affects territorial males of the Lake Tanganyika cichlid fish Telmatochromis vittatus, we examined the reproductive ecology of territorial males in Mtondwe and compared it with that of a neighboring Wonzye population, where nest density differs from that at Mtondwe. In Wonzye, with high nest density, male tactics change with their body size from a territorial to a non-territorial parasitic tactic called piracy in which they conquer several nests defended by territorial males and take over the nests while females are spawning. These "pirate" males could decrease the costs incurred by travelling among nests by exclusively targeting aggregations of nests in close proximity while avoiding separate nests. Territorial males in Wonzye sacrifice the potential higher attractiveness offered by large nests and instead compete for nests farther from neighbors on which pirates less frequently intrude. In contrast, the Mtondwe population had lower nest density and piracy was absent. Given that the success of piracy depends on the close proximity of nests, nest density is likely responsible for the observed variation in the occurrence of piracy between the two populations. Furthermore, in Mtondwe, territorial males competed for larger nests and were smaller than the territorial males in Wonzye. Thus, this lower nest density may free territorial males from the selection pressures for increased size caused by both defense against nest piracy and the need to develop into pirates as they grow.

Biomarker discovery study design for type 1 diabetes in The Environmental Determinants of Diabetes in the Young (TEDDY) study.

PubMed

Lee, Hye-Seung; Burkhardt, Brant R; McLeod, Wendy; Smith, Susan; Eberhard, Chris; Lynch, Kristian; Hadley, David; Rewers, Marian; Simell, Olli; She, Jin-Xiong; Hagopian, Bill; Lernmark, Ake; Akolkar, Beena; Ziegler, Anette G; Krischer, Jeffrey P

2014-07-01

The Environmental Determinants of Diabetes in the Young planned biomarker discovery studies on longitudinal samples for persistent confirmed islet cell autoantibodies and type 1 diabetes using dietary biomarkers, metabolomics, microbiome/viral metagenomics and gene expression. This article describes the details of planning The Environmental Determinants of Diabetes in the Young biomarker discovery studies using a nested case-control design that was chosen as an alternative to the full cohort analysis. In the frame of a nested case-control design, it guides the choice of matching factors, selection of controls, preparation of external quality control samples and reduction of batch effects along with proper sample allocation. Our design is to reduce potential bias and retain study power while reducing the costs by limiting the numbers of samples requiring laboratory analyses. It also covers two primary end points (the occurrence of diabetes-related autoantibodies and the diagnosis of type 1 diabetes). The resulting list of case-control matched samples for each laboratory was augmented with external quality control samples. Copyright © 2013 John Wiley & Sons, Ltd.

Blood-based cerebral biomarkers in preeclampsia: Plasma concentrations of NfL, tau, S100B and NSE during pregnancy in women who later develop preeclampsia - A nested case control study.

PubMed

Bergman, Lina; Zetterberg, Henrik; Kaihola, Helena; Hagberg, Henrik; Blennow, Kaj; Åkerud, Helena

2018-01-01

To evaluate if concentrations of the neuronal proteins neurofilament light chain and tau are changed in women developing preeclampsia and to evaluate the ability of a combination of neurofilament light chain, tau, S100B and neuron specific enolase in identifying neurologic impairment before diagnosis of preeclampsia. A nested case-control study within a longitudinal study cohort was performed. 469 healthy pregnant women were enrolled between 2004-2007 and plasma samples were collected at gestational weeks 10, 25, 28, 33 and 37. Plasma concentrations of tau and neurofilament light chain were analyzed in 16 women who eventually developed preeclampsia and 36 controls throughout pregnancy with single molecule array (Simoa) method and compared within and between groups. S100B and NSE had been analyzed previously in the same study population. A statistical model with receiving characteristic operation curve was constructed with the four biomarkers combined. Plasma concentrations of neurofilament light chain were significantly increased in women who developed preeclampsia in gestational week 33 (11.85 ng/L, IQR 7.48-39.93 vs 6.80 ng/L, IQR 5.65-11.40) and 37 (22.15 ng/L, IQR 10.93-35.30 vs 8.40 ng/L, IQR 6.40-14.30) and for tau in gestational week 37 (4.33 ng/L, IQR 3.97-12.83 vs 3.77 ng/L, IQR 1.91-5.25) in contrast to healthy controls. A combined model for preeclampsia with tau, neurofilament light chain, S100B and neuron specific enolase in gestational week 25 displayed an area under the curve of 0.77, in week 28 it was 0.75, in week 33 it was 0.89 and in week 37 it was 0.83. Median week for diagnosis of preeclampsia was at 38 weeks of gestation. Concentrations of both tau and neurofilament light chain are increased in the end of pregnancy in women developing preeclampsia in contrast to healthy pregnancies. Cerebral biomarkers might reflect cerebral involvement before onset of disease.

National study of suicide in all people with a criminal justice history.

PubMed

Webb, Roger T; Qin, Ping; Stevens, Hanne; Mortensen, Preben B; Appleby, Louis; Shaw, Jenny

2011-06-01

Previous research has focused on suicide among male prisoners and ex-prisoners, but little is known about risk in the wider offender population. To examine suicide risk over 3 decades among all people processed by a national criminal justice system. Nested case-control study. The whole Danish population. Interlinked national registers identified all adult suicides during 1981 to 2006 according to any criminal justice system contact since 1980. Exposure was defined according to history of criminal justice adjudication, up to and including each subject's last judicial verdict before suicide (or date of matching for controls). There were 27 219 suicides and 524 899 controls matched on age, sex, and time, ie, controls were alive when their matched case died. Suicide. More than a third of all male cases had a criminal justice history, but relative risk against the general population was higher for women than men. Independent effects linked with criminal justice exposure persisted with confounder adjustment. Suicide risk was markedly elevated with custodial sentencing, but the strongest effects were with sentencing to psychiatric treatment and with charges conditionally withdrawn. Risk was raised even in people with a criminal justice history but without custodial sentences or guilty verdicts. It was especially high with recent or frequent contact and in people charged with violent offenses. We examined a section of society in which major health and social problems frequently coexist including offending, psychopathology, and suicidal behavior. The need for developing more far-reaching national suicide prevention strategies is indicated. In particular, improved mental health service provision is needed for all people in contact with the criminal justice system, including those not found guilty and those not given custodial sentences. Our findings also suggest that public services should be better coordinated to tackle co-occurring health and social problems more effectively.

Environmental modulation of androgen levels and secondary sex characters in two populations of the peacock blenny Salaria pavo.

PubMed

Saraiva, João L; Gonçalves, David M; Oliveira, Rui F

2010-02-01

Morphology and endocrinology were studied in two populations of the peacock blenny Salaria pavo, with different regimes of sexual selection imposed by differences in nest site availability. The peacock blenny is a small, sexually dimorphic benthic fish that presents exclusive paternal care of the clutch and inhabits rocky shores of the Mediterranean and adjacent Atlantic areas. In a population from the Gulf of Trieste (Northern Adriatic sea) inhabiting rocky shores where nest sites are abundant, male-male competition for nests is low, males court females and a low frequency of alternative reproductive tactics (small, parasitic female-mimicking sneaker males that change tactic into nest holders in subsequent breeding seasons) occurs. Conversely at Ria Formosa, a coastal lagoon in Southern Portugal, where nest sites are scarce and highly aggregated, male-male competition for nests is very high, there is sex-role reversal with female courtship and a high frequency of alternative reproductive tactics is observed. Concomitantly, at Ria Formosa nest holder males are larger and present more developed secondary sex characters and higher levels of 11KT than at the Gulf of Trieste. However, the gonads of nest holders and parasitic males were larger in the Gulf of Trieste population. Competition for nests at Ria Formosa seems to promote more developed secondary sex characters in nest site scarcity conditions, while competition for females at the Gulf of Trieste seems to be spurring sperm competition among males in populations where nest sites are more abundant. 11KT was thus associated with the development and expression of secondary sex characters in contrasting environments. These results exemplify how the modulation of behavioral plasticity and secondary sex characters by the social environment can be mediated by androgens. Copyright 2009 Elsevier Inc. All rights reserved.

Long-term use of steroids protects from the development of symptomatic diverticulitis requiring hospitalization in the Asian population.

PubMed

Chang, Shen-Shong; Hu, Hsiao-Yun

2015-01-01

The pathophysiology of diverticulitis is poorly understood. Factors such as physical inactivity, constipation, obesity, smoking, and the use of nonsteroidal antiinflammatory drugs (NSAIDs) have been associated with an increased risk of diverticular disease. To evaluate whether patients exhibiting long-term steroid use are at increased risk of colonic diverticulitis. We conducted a population-based, nested case-control study. Data were retrospectively collected from the National Health Insurance Research Database. The study cohort comprised patients diagnosed with diverticulitis, identified using inpatient discharge records using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes (562.11 and 562.13), and those who were administered one or more prescriptions for corticosteroids for systemic use. Control patients were matched to cases by age, sex, NSAID use, laxative drug use, and index date. We enrolled 690 patients with colonic diverticulitis and 2760 in the control group. The adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using conditional logistic regression. Compared with steroid nonusers, the adjusted ORs were 0.60 (95% CI = 0.35-1.06) and 0.80 (95% CI = 0.64-1.008) in current steroid users and previous steroid users, respectively. In addition, the adjusted ORs were 0.55 (95% CI = 0.31-0.98), 0.57 (95% CI = 0.31-0.98), and 0.44 (95% CI = 0.22-0.86) for steroid use duration more than half time by an exposure period of 90 days, 180 days, and 365 days before the claim date of colonic diverticulitis, respectively. The results indicated that long-term steroid use within one year is associated with lower risk of colonic diverticulitis.

Predictors of early postpartum mental distress in mothers with midwifery home care--results from a nested case-control study.

PubMed

Staehelin, Katharina; Kurth, Elisabeth; Schindler, Christian; Schmid, Monika; Zemp Stutz, Elisabeth

2013-08-27

The prevalence of early postpartum mental health conditions is high. Midwives and other health professionals visiting women at home may identify mothers at risk. This seems crucial given decreasing trends of length of hospital stay after childbirth. This study aimed to identify predictors of maternal mental distress in a midwifery home care setting. Using the statistical database of independent midwives' services in Switzerland in 2007, we conducted a matched nested case-control study. Out of a source population of 34,295 mothers with midwifery home care in the first ten days after childbirth, 935 mothers with maternal distress and 3,645 controls, matched by midwife, were included. We analysed whether socio-demographic, maternal and neonatal factors predict maternal mental distress by multivariable conditional logistic regression analysis. Infant crying problems and not living with a partner were the strongest predictors for maternal distress, whereas higher parity was the most protective factor. Significantly elevated risks were also found for older age, lower educational levels, breast/breastfeeding problems, infant weight gain concerns, neonatal pathologies and use of midwifery care during pregnancy. A lower likelihood for maternal distress was seen for non-Swiss nationality, full-time employment before birth, intention to return to work after birth and midwife-led birth. The study informs on predictors of maternal mental distress identified in a home care setting in the early postpartum period. Midwives and other health care professionals should pay particular attention to mothers of excessively crying infants, single mothers and primipara, and assess the need for support of these mothers.

A model of northern pintail productivity and population growth rate

USGS Publications Warehouse

Flint, Paul L.; Grand, James B.; Rockwell, Robert F.

1998-01-01

Our objective was to synthesize individual components of reproductive ecology into a single estimate of productivity and to assess the relative effects of survival and productivity on population dynamics. We used information on nesting ecology, renesting potential, and duckling survival of northern pintails (Anas acuta) collected on the Yukon-Kuskokwim Delta (Y-K Delta), Alaska, 1991-95, to model the number of ducklings produced under a range of nest success and duckling survival probabilities. Using average values of 25% nest success, 11% duckling survival, and 56% renesting probability from our study population, we calculated that all young in our population were produced by 13% of the breeding females, and that early-nesting females produced more young than later-nesting females. Further, we calculated, on average, that each female produced only 0.16 young females/nesting season. We combined these results with estimates of first-year and adult survival to examine the growth rate (X) of the population and the relative contributions of these demographic parameters to that growth rate. Contrary to aerial survey data, the population projection model suggests our study population is declining rapidly (X = 0.6969). The relative effects on population growth rate were 0.1175 for reproductive success, 0.1175 for first-year survival, and 0.8825 for adult survival. Adult survival had the greatest influence on X for our population, and this conclusion was robust over a range of survival and productivity estimates. Given published estimates of annual survival for adult females (61%), our model suggested nest success and duckling survival need to increase to approximately 40% to achieve population stability. We discuss reasons for the apparent discrepancy in population trends between our model and aerial surveys in terms of bias in productivity and survival estimates.

Use of artificial nests to investigate predation on freshwater turtle nests

Treesearch

Michael N. Marchand; John A. Litvaitis; Thomas J. Maier; Richard M. DeGraaf

2002-01-01

Habitat fragmentation has raised concerns that populations of generalist predators have increased and are affecting a diverse group of prey. Previous research has included the use of artificial nests to investigate the role of predation on birds that nest on or near the ground. Because predation also is a major factor limiting populations of freshwater turtles, we...

Better living through conifer removal: A demographic analysis of sage-grouse vital rates.

PubMed

Severson, John P; Hagen, Christian A; Tack, Jason D; Maestas, Jeremy D; Naugle, David E; Forbes, James T; Reese, Kerry P

2017-01-01

Sagebrush (Artemisia spp.) obligate wildlife species such as the imperiled greater sage-grouse (Centrocercus urophasianus) face numerous threats including altered ecosystem processes that have led to conifer expansion into shrub-steppe. Conifer removal is accelerating despite a lack of empirical evidence on grouse population response. Using a before-after-control-impact design at the landscape scale, we evaluated effects of conifer removal on two important demographic parameters, annual survival of females and nest survival, by monitoring 219 female sage-grouse and 225 nests in the northern Great Basin from 2010 to 2014. Estimates from the best treatment models showed positive trends in the treatment area relative to the control area resulting in an increase of 6.6% annual female survival and 18.8% nest survival relative to the control area by 2014. Using stochastic simulations of our estimates and published demographics, we estimated a 25% increase in the population growth rate in the treatment area relative to the control area. This is the first study to link sage-grouse demographics with conifer removal and supports recommendations to actively manage conifer expansion for sage-grouse conservation. Sage-grouse have become a primary catalyst for conservation funding to address conifer expansion in the West, and these findings have important implications for other ecosystem services being generated on the wings of species conservation.

POPULATION-BASED EXPOSURE MEASUREMENTS IN ARIZONA: A PHASE FIELD STUDY IN SUPPORT OF THE NATIONAL HUMAN EXPOSURE ASSESSMENT SURVEY

EPA Science Inventory

The objectives of this field study are to determine the distributions of total human exposures to multi-media pollutants in the classes of metals, pesticides, and volatile organic compounds (VOCs) by studying a proportionate-based sample of the total population (with a nested des...

Nesting success of Northern Pintails on the coastal Yukon-Kuskokwim Delta, Alaska

USGS Publications Warehouse

Flint, Paul L.; Grand, James B.

1996-01-01

We studied nesting chronology and success of Northern Pintails (Anas acuta) on the coastal Yukon-Kuskokwim Delta, Alaska during the summers of 1991-1993. We found a total of 795 nests during three annual searches of a 27.4 km2 area. Minimum nest density averaged 9.67 nests per km2. Nesting success varied among years and ranged from 43.12% in 1991 to 10.74% in 1993 (average 23.95%). Most nest loss was the result of predation and tidal flooding. Daily nest survival probability declined with nest initiation date in all three years and also varied with nest age in 1992. Clutch size averaged 7.63 ± 0.067 (SE) eggs per nest and was larger than reported for other populations of Northern Pintails. Clutch size declined during the 44-47 day nesting interval at a greater rate than reported for other populations of Northern Pintails. We conclude that sub-arctic and prairie nesting Northern Pintails have similar reproductive potentials.

Inter-seasonal maintenance of individual nest site preferences in hawksbill sea turtles.

PubMed

Kamel, Stephanie J; Mrosovsky, N

2006-11-01

Within a single population of hawksbill sea turtles (Eretmochelys imbricata), we found a behavioral polymorphism for maternal nest site choice with respect to beach microhabitat characteristics. Some females preferred to nest in littoral forest and in places with overstory vegetation cover, and others preferred to nest in more open, deforested areas. Nest site choice was consistent within and between nesting seasons two years apart. This was not a result of females simply returning to the same location along the shoreline; beach sections used by individual turtles varied between seasons. Nest site choice was not influenced by changes in beach environment (e.g., beach width and foliage cover) or by changes in females' reproductive output (e.g., clutch size), suggesting that fidelity to particular microhabitats is a major determinant of the observed nesting patterns. Because hawksbills exhibit temperature-dependent sex determination, if the behavioral polymorphism in nest site choice has a genetic basis, as is plausible, then this would have implications for sex ratio evolution and offspring survival. By taking an individual-based approach to the study of maternal behavior we reveal previously overlooked individual variation and hope to provide some impetus for more detailed studies of nest site choice.

Epidemiology of Parkinson disease in the city of Kolkata, India

PubMed Central

Das, S.K.; Misra, A.K.; Ray, B.K.; Hazra, A.; Ghosal, M.K.; Chaudhuri, A.; Roy, T.; Banerjee, T.K.; Raut, D.K.

2010-01-01

Objective: No well-designed longitudinal study on Parkinson disease (PD) has been conducted in India. Therefore, we planned to determine the prevalence, incidence, and mortality rates of PD in the city of Kolkata, India, on a stratified random sample through a door-to-door survey. Method: This study was undertaken between 2003 to 2007 with a validated questionnaire by a team consisting of 4 trained field workers in 3 stages. Field workers screened the cases, later confirmed by a specialist doctor. In the third stage, a movement disorders specialist undertook home visits and reviewed all surviving cases after 1 year from last screening. Information on death was collected through verbal autopsy. A nested case-control study (1:3) was also undertaken to determine putative risk factors. The rates were age adjusted to the World Standard Population. Result: A total population of 100,802 was screened. The age-adjusted prevalence rate (PR) and average annual incidence rate were 52.85/100,000 and 5.71/100,000 per year, respectively. The slum population showed significantly decreased PR with age compared with the nonslum population. The adjusted average annual mortality rate was 2.89/100,000 per year. The relative risk of death was 8.98. The case-control study showed that tobacco chewing protected and hypertension increased PD occurrence. Conclusion: This study documented lower prevalence and incidence of PD as compared with Caucasian and a few Oriental populations. The mortality rates were comparable. The decreased age-specific PR among slum populations and higher relative risk of death need further probing. GLOSSARY AAIR = average annual incidence rate; AAMR = average annual mortality rate; CI = confidence interval; FSQ = family screening questionnaire; ICC = intraclass correlation coefficient; IR = incidence rate; MD = movement disorder; NSSO = National Sample Survey Organization; OR = odds ratio; PD = Parkinson disease; PPS = parkinsonism plus syndrome; PR = prevalence rate; PRM = Poisson regression modeling; RR = relative risk; SP = secondary parkinsonism; VA = verbal autopsy. PMID:20938028

Maternal polycystic ovary syndrome and the risk of autism spectrum disorders in the offspring: a population-based nationwide study in Sweden.

PubMed

Kosidou, K; Dalman, C; Widman, L; Arver, S; Lee, B K; Magnusson, C; Gardner, R M

2016-10-01

Although many studies indicate the interplay of genetic and environmental factors in the etiology of autism spectrum disorder (ASD), our limited understanding of the underlying mechanisms hampers the development of effective ways of detecting and preventing the disorder. Recent studies support the hypothesis that prenatal androgen exposure contributes to the development of ASD. This would suggest that maternal polycystic ovary syndrome (PCOS), a condition associated with excess androgens, would increase the risk of ASD in the offspring. We conducted a matched case-control study nested within the total population of Sweden (children aged 4-17 who were born in Sweden from 1984 to 2007). The sample consisted of 23 748 ASD cases and 208 796 controls, matched by birth month and year, sex and region of birth. PCOS and ASD were defined from ICD codes through linkage to health-care registers. Maternal PCOS increased the odds of ASD in the offspring by 59%, after adjustment for confounders (odds ratio (OR) 1.59, 95% confidence interval (CI) 1.34-1.88). The odds of offspring ASD were further increased among mothers with both PCOS and obesity, a condition common to PCOS that is related to more severe hyperandrogenemia (OR 2.13, 95% CI 1.46-3.10). Risk estimates did not differ between sexes. In conclusion, children of women with PCOS appear to have a higher risk of developing ASD. This finding awaits confirmation, and exploration of potentially underlying mechanisms, including the role of sex steroids in the etiology of ASD.

Temperature Effects on Development and Phenotype in a Free-Living Population of Western Pond Turtles (Emys marmorata).

PubMed

Christie, Nicole E; Geist, Nicholas R

Changes in temperature regimes are occurring globally due to climate change as well as habitat alterations. Temperatures are expected to continue to rise in the future, along with a greater degree of climatic instability. Such changes could have potentially serious consequences for oviparous ectotherms, especially those with temperature-dependent sex determination. To investigate the effects of temperature on a range of developmental phenomena in a population of western pond turtles (Emys marmorata), we placed temperature sensors on top of each layer of eggs within nests and recorded temperatures hourly through the first 2-3 mo of incubation. These methods allowed us to look at in situ nest temperatures with high resolution. We found that mean incubation temperatures were similar between different nests and at different levels within nests but that incubation temperature fluctuations and maximum incubation temperatures differed greatly in both cases. The hatchling turtles were more likely to be female if they spent 30% or more of their sex-determining period of incubation above 29°C. Hatching success was best predicted by the maximum incubation temperature. We also found that incubation duration tended to be shorter as the mean temperature increased. However, exposure to either extremely high or low temperatures extended incubation times.

Maternal obesity and congenital heart defects: a population-based study123

PubMed Central

Mills, James L; Troendle, James; Conley, Mary R; Carter, Tonia; Druschel, Charlotte M

2010-01-01

Background: Obesity affects almost one-third of pregnant women and causes many complications, including neural tube defects. It is not clear whether the risk of congenital heart defects, the most common malformations, is also increased. Objective: This study was conducted to determine whether obesity is associated with an increased risk of congenital heart defects. Design: A population-based, nested, case-control study was conducted in infants born with congenital heart defects and unaffected controls from the cohort of all births (n = 1,536,828) between 1993 and 2003 in New York State, excluding New York City. The type of congenital heart defect, maternal body mass index (BMI; in kg/m2), and other risk factors were obtained from the Congenital Malformations Registry and vital records. Mothers of 7392 congenital heart defect cases and 56,304 unaffected controls were studied. Results: All obese women (BMI ≥ 30) were significantly more likely than normal-weight women (BMI: 19–24.9) to have children with a congenital heart defect [odds ratio (OR): 1.15; 95% CI: 1.07, 1.23; P < 0.0001]. Overweight women were not at increased risk (OR: 1.00; 95% CI: 0.94, 1.06). The risk in morbidly obese women (BMI ≥ 40) was higher (OR: 1.33; 95% CI: 1.15, 1.54; P = 0.0001) than that in obese women with a BMI of 30–39.9 (OR: 1.11; 95% CI: 1.04, 1.20; P = 0.004). There was a highly significant trend of increasing OR for congenital heart defects with increasing maternal obesity (P < 0.0001). The offspring of obese women had significantly higher ORs for atrial septal defects, hypoplastic left heart syndrome, aortic stenosis, pulmonic stenosis, and tetralogy of Fallot. Conclusions: Obese, but not overweight, women are at significantly increased risk of bearing children with a range of congenital heart defects, and the risk increases with increasing BMI. Weight reduction as a way to reduce risk should be investigated. PMID:20375192

Selection bias in population-based cancer case-control studies due to incomplete sampling frame coverage.

PubMed

Walsh, Matthew C; Trentham-Dietz, Amy; Gangnon, Ronald E; Nieto, F Javier; Newcomb, Polly A; Palta, Mari

2012-06-01

Increasing numbers of individuals are choosing to opt out of population-based sampling frames due to privacy concerns. This is especially a problem in the selection of controls for case-control studies, as the cases often arise from relatively complete population-based registries, whereas control selection requires a sampling frame. If opt out is also related to risk factors, bias can arise. We linked breast cancer cases who reported having a valid driver's license from the 2004-2008 Wisconsin women's health study (N = 2,988) with a master list of licensed drivers from the Wisconsin Department of Transportation (WDOT). This master list excludes Wisconsin drivers that requested their information not be sold by the state. Multivariate-adjusted selection probability ratios (SPR) were calculated to estimate potential bias when using this driver's license sampling frame to select controls. A total of 962 cases (32%) had opted out of the WDOT sampling frame. Cases age <40 (SPR = 0.90), income either unreported (SPR = 0.89) or greater than $50,000 (SPR = 0.94), lower parity (SPR = 0.96 per one-child decrease), and hormone use (SPR = 0.93) were significantly less likely to be covered by the WDOT sampling frame (α = 0.05 level). Our results indicate the potential for selection bias due to differential opt out between various demographic and behavioral subgroups of controls. As selection bias may differ by exposure and study base, the assessment of potential bias needs to be ongoing. SPRs can be used to predict the direction of bias when cases and controls stem from different sampling frames in population-based case-control studies.

Contrasting patterns of nest survival and postfledging survival in ovenbirds and Acadian flycatchers in Missouri forest fragments

Treesearch

Julianna M. A. Jenkins; Frank R. Thompson; John Faaborg

2016-01-01

We can improve our ability to assess population viability and forecast population growth under different scenarios by understanding factors that limit population parameters in each stage of the annual cycle. Postfledging mortality rates may be as variable as nest survival across regions and fragmentation gradients, although factors that negatively impact nest survival...

Reproductive success of Mariana swiftlets (Aerodramus bartschi) on the Hawaiian island of O'ahu

USGS Publications Warehouse

Johnson, Nathan C.; Haig, Susan M.; Mosher, Stephen M.; Hollenbeck, Jeff P.

2017-01-01

Mariana Swiftlets (Aerodramus bartschi) are federally listed as endangered, with populations currently limited to just three islands in the Mariana Islands plus an introduced population on the Hawaiian island of O'ahu. Before efforts are made to reintroduce Mariana Swiftlets to other islands in the Mariana archipelago, additional information is needed concerning their breeding biology. Therefore, our objective was to examine the reproductive biology of Mariana Swiftlets over five annual cycles on the Hawaiian island of O'ahu. This introduced population used a human-made tunnel for roosting and nesting, and was studied as a surrogate to negate interference with endangered populations in the Mariana Islands. Active nests (N = 478) were observed in every month of the year, with peak nesting activity between May and September. All clutches consisted of one egg. Mean duration of incubation and nestling periods were 23.9 d (range = 18–30 d, N = 233) and 55.0 d (range = 41–84 d, N = 228), respectively. Estimated nest success was 63%. Over half (52%) of nest failures were attributed to eggs found on the tunnel floor. Predation by rats (Rattus spp.) was also an important cause of nest failure and often resulted in the loss of most active nests. However, Mariana Swiftlets did re-nest after these predation events. Our results suggest that rat predation of both nests and adults may limit growth of the Mariana Swiftlet population on O'ahu, and could also affect the chances for successful establishment of relocated populations in the Mariana Islands. Another limiting factor on O'ahu is that only one nesting site is apparently available on the island. Current goals for downlisting Mariana Swiftlets from endangered to threatened include establishing populations on Guam, Rota, Aguiguan, and Saipan. To meet these goals, the population of Mariana Swiftlets on O'ahu can be important for testing reintroduction techniques, learning more about the natural history of these swiftlets, and providing individuals for reintroduction efforts in the Mariana Islands.

Aetiology of childhood pneumonia in a well vaccinated South African birth cohort: a nested case-control study of the Drakenstein Child Health Study.

PubMed

Zar, Heather J; Barnett, Whitney; Stadler, Attie; Gardner-Lubbe, Sugnet; Myer, Landon; Nicol, Mark P

2016-06-01

Pneumonia is a leading cause of mortality and morbidity in children globally. The cause of pneumonia after introduction of the 13-valent pneumococcal conjugate vaccine (PCV13) has not been well studied in low-income and middle-income countries, and most data are from cross-sectional studies of children admitted to hospital. We aimed to longitudinally investigate the incidence and causes of childhood pneumonia in a South African birth cohort. We did a nested case-control study of children in the Drakenstein Child Health Study who developed pneumonia from May 29, 2012, to Dec 1, 2014. Children received immunisations including acellular pertussis vaccine and PCV13. A nested subgroup had nasopharyngeal swabs collected every 2 weeks throughout infancy. We identified pneumonia episodes and collected blood, nasopharyngeal swabs, and induced sputum specimens. We used multiplex real-time PCR to detect pathogens in nasopharyngeal swabs and induced sputum of pneumonia cases and in nasopharyngeal swabs of age-matched and site-matched controls. To show associations between organisms and pneumonia we used conditional logistic regression; results are presented as odds ratios (ORs) with 95% CIs. 314 pneumonia cases occurred (incidence of 0·27 episodes per child-year, 95% CI 0·24-0·31; median age 5 months [IQR 3-9]) in 967 children during 1145 child-years of follow-up. 60 (21%) cases of pneumonia were severe (incidence 0·05 episodes per child-year [95% CI 0·04-0·07]) with a case fatality ratio of 1% (three deaths). A median of five organisms (IQR 4-6) were detected in cases and controls with nasopharyngeal swabs, and a median of six organisms (4-7) recorded in induced sputum (p=0·48 compared with nasopharyngeal swabs). Bordetella pertussis (OR 11·08, 95% CI 1·33-92·54), respiratory syncytial virus (8·05, 4·21-15·38), or influenza virus (4·13, 2·06-8·26) were most strongly associated with pneumonia; bocavirus, adenovirus, parainfluenza virus, Haemophilus influenzae, and cytomegalovirus were also associated with pneumonia. In cases, testing of induced sputum in addition to nasopharyngeal swabs provided incremental yield for detection of B pertussis and several viruses. Pneumonia remains common in this highly vaccinated population. Respiratory syncytial virus was the most frequently detected pathogen associated with pneumonia; influenza virus and B pertussis were also strongly associated with pneumonia. Testing of induced sputum increases the yield for detection of several organisms. New vaccines and strategies are needed to address the burden of childhood pneumonia. Bill & Melinda Gates Foundation, Medical Research Council South Africa, National Research Foundation South Africa, National Institute of Health, and H3Africa. Copyright © 2016 Elsevier Ltd. All rights reserved.

Serum 25-Hydroxyvitamin D and Breast Cancer in the Military: A Case-control Study Utilizing Pre-diagnostic Serum

DTIC Science & Technology

2013-01-08

15. Shin MH, Holmes MD, Hankinson SE, Wu K, Colditz GA, Willett WC (2002) Intake of dairy products, calcium, and vitamin D and risk of breast cancer...Serum 25-hydroxyvitamin D concentrations and postmenopausal breast cancer risk: a nested case control study in the Cancer Prevention Study-II Nutrition

Communal nesting under climate change: fitness consequences of higher incubation temperatures for a nocturnal lizard.

PubMed

Dayananda, Buddhi; Gray, Sarah; Pike, David; Webb, Jonathan K

2016-07-01

Communal nesting lizards may be vulnerable to climate warming, particularly if air temperatures regulate nest temperatures. In southeastern Australia, velvet geckos Oedura lesueurii lay eggs communally inside rock crevices. We investigated whether increases in air temperatures could elevate nest temperatures, and if so, how this could influence hatching phenotypes, survival, and population dynamics. In natural nests, maximum daily air temperature influenced mean and maximum daily nest temperatures, implying that nest temperatures will increase under climate warming. To determine whether hotter nests influence hatchling phenotypes, we incubated eggs under two fluctuating temperature regimes to mimic current 'cold' nests (mean = 23.2 °C, range 10-33 °C) and future 'hot' nests (27.0 °C, 14-37 °C). 'Hot' incubation temperatures produced smaller hatchlings than did cold temperature incubation. We released individually marked hatchlings into the wild in 2014 and 2015, and monitored their survival over 10 months. In 2014 and 2015, hot-incubated hatchlings had higher annual mortality (99%, 97%) than cold-incubated (11%, 58%) or wild-born hatchlings (78%, 22%). To determine future trajectories of velvet gecko populations under climate warming, we ran population viability analyses in Vortex and varied annual rates of hatchling mortality within the range 78- 96%. Hatchling mortality strongly influenced the probability of extinction and the mean time to extinction. When hatchling mortality was >86%, populations had a higher probability of extinction (PE: range 0.52- 1.0) with mean times to extinction of 18-44 years. Whether future changes in hatchling survival translate into reduced population viability will depend on the ability of females to modify their nest-site choices. Over the period 1992-2015, females used the same communal nests annually, suggesting that there may be little plasticity in maternal nest-site selection. The impacts of climate change may therefore be especially severe on communal nesting species, particularly if such species occupy thermally challenging environments. © 2016 John Wiley & Sons Ltd.

Increased Use of Community Medicine Distributors and Rational Use of Drugs in Children Less than Five Years of Age in Uganda Caused by Integrated Community Case Management of Fever

PubMed Central

Kalyango, Joan N.; Lindstrand, Ann; Rutebemberwa, Elizeus; Ssali, Sarah; Kadobera, Daniel; Karamagi, Charles; Peterson, Stefan; Alfven, Tobias

2012-01-01

We compared use of community medicine distributors (CMDs) and drug use under integrated community case management and home-based management strategies in children 6–59 months of age in eastern Uganda. A cross-sectional study with 1,095 children was nested in a cluster randomized trial with integrated community case management (CMDs treating malaria and pneumonia) as the intervention and home-based management (CMDs treating only malaria) as the control. Care-seeking from CMDs was higher in intervention areas (31%) than in control areas (22%; P = 0.01). Prompt and appropriate treatment of malaria was higher in intervention areas (18%) than in control areas (12%; P = 0.03) and among CMD users (37%) than other health providers (9%). The mean number of drugs among CMD users compared with other health providers was 1.6 versus 2.4 in intervention areas and 1.4 versus 2.3 in control areas. Use of CMDs was low. However, integrated community case management of childhood illnesses increased use of CMDs and rational drug use. PMID:23136276

A Case–Control Study of Lung Cancer Nested in a Cohort of European Asphalt Workers

PubMed Central

Olsson, Ann; Kromhout, Hans; Agostini, Michela; Hansen, Johnni; Lassen, Christina Funch; Johansen, Christoffer; Kjaerheim, Kristina; Langård, Sverre; Stücker, Isabelle; Ahrens, Wolfgang; Behrens, Thomas; Lindbohm, Marja-Liisa; Heikkilä, Pirjo; Heederik, Dick; Portengen, Lützen; Shaham, Judith; Ferro, Gilles; de Vocht, Frank; Burstyn, Igor; Boffetta, Paolo

2010-01-01

Background We conducted a nested case–control study in a cohort of European asphalt workers in which an increase in lung cancer risk has been reported among workers exposed to airborne bitumen fume, although potential bias and confounding were not fully addressed. Objective We investigated the contribution of exposure to bitumen, other occupational agents, and tobacco smoking to the risk of lung cancer among asphalt workers. Methods Cases were cohort members in Denmark, Finland, France, Germany, the Netherlands, Norway, and Israel who had died of lung cancer between 1980 and the end of follow-up (2002–2005). Controls were individually matched in a 3:1 ratio to cases on year of birth and country. We derived exposure estimates for bitumen fume and condensate, organic vapor, and polycyclic aromatic hydrocarbons, as well as for asbestos, crystalline silica, diesel motor exhaust, and coal tar. Odds ratios (ORs) were calculated for ever-exposure, duration, average exposure, and cumulative exposure after adjusting for tobacco smoking and exposure to coal tar. Results A total of 433 cases and 1,253 controls were included in the analysis. The OR was 1.12 [95% confidence interval (CI), 0.84–1.49] for inhalation exposure to bitumen fume and 1.17 (95% CI, 0.88–1.56) for dermal exposure to bitumen condensate. No significant trend was observed between lung cancer risk and duration, average exposure, or cumulative exposure to bitumen fume or condensate. Conclusions We found no consistent evidence of an association between indicators of either inhalation or dermal exposure to bitumen and lung cancer risk. A sizable proportion of the excess mortality from lung cancer relative to the general population observed in the earlier cohort phase is likely attributable to high tobacco consumption and possibly to coal tar exposure, whereas other occupational agents do not appear to play an important role. PMID:20529766

Effects on forest birds of DDT used for gypsy moth control in Pennsylvania

USGS Publications Warehouse

Hotchkiss, N.; Pough, R.H.

1946-01-01

1. Systematic censuses of the birds on three 40-acre tracts of forest near Scranton, Lackawanna County, Pennsylvania, were made between May 1 and June 27, 1945, to determine the breeding populations....2. Between May 24 and June 1 a 600-acre area enclosing the first (Mile Square) was sprayed by airplane with DDT in oil solution at 5 pounds per acre. On June 9 a 350-acre area enclosing the second tract (Maple Lake) was sprayed with 1pound of DDT per acre. The third tract (Check) was not treated....3. Within 48 hours after treatment of the Mile Square tract, five sick birds were found with symptoms of DDT poisoning, and all died. Two other dead birds were found, and two nests apparently were abandoned. Species involved were red-eyed vireo (3), black-and-white warbler, black-throated blue warbler (nest abandoned), ovenbird (bird died, nest abandoned), redstart, and scarlet tanager....Within 48 hours after application of DDT to the final portion of the tract (on June 1) the population of living birds appeared to have been much reduced, and this condition continued. Before spraying the population total for all species was 1.6 pairs (3.2 birds) per acre. Three days after spraying had been completed there were only two singing males in the entire area; but on June 13 the estimated population was 0.5 bird per acre.....4. After DDT was applied to the Maple Lake tract, careful watch was kept for changes in the bird population and as to nest conditions there and on the Check tract. The apparent total reduction for all species in the Maple Lake tract was from 2.7 pairs to 2.6 pairs per acre; and in the Check tract from 2.7 pairs to 2.4 pairs per acre. Neither these changes nor the observed abandonment of nests and nestling mortality could be attributed to use of DDT.

Factors influencing reproductive performance of northern bobwhite in South Florida

USGS Publications Warehouse

Rolland, V.; Hostetler, J.A.; Hines, T.C.; Percival, H.F.; Oli, M.K.

2011-01-01

Reproductive success is a critical component of individual fitness, and also an important determinant of growth rates of populations characterized by early maturity and high fecundity. We used radiotelemetry data collected during 2003-2008 to estimate reproductive parameters in a declining northern bobwhite (Colinus virginianus) population in South Florida, and to test hypotheses regarding factors influencing these parameters. The overall clutch size was 12.10 ?? 0.22, but females laid more eggs in their first clutch (12.43 ?? 0.24) than in subsequent clutches (10.19 ?? 0.53) within a nesting season. Daily nest survival was higher for first (0.966 ?? 0.003) than subsequent nests (0.936 ?? 0.011). Hatchability (proportion of laid eggs that hatched conditional upon nest survival to hatching) was 0.853 ?? 0.008, but was higher for nests incubated by females (0.873 ?? 0.009) than those incubated by males (0.798 ?? 0.018). The proportion of individuals attempting a second nest was 0.112 ?? 0.024 and 0.281 ?? 0.040 when the first nest was successful and failed, respectively. Hatchability was lower when the nesting habitat was burned the previous winter. We found no evidence that food strip density (a management practice to provide supplemental food) influenced any of the reproductive parameters. Mean summer temperature affected hatchability, nest survival, and proportion of nests incubated by males. Overall, the reproductive output in our study population was lower than that reported for most other bobwhite populations, indicating that low reproductive performance may have contributed to bobwhite population declines in our study site. These results suggest that current management practices, particularly those related to habitat and harvest management, need careful evaluation. ?? 2010 Springer-Verlag.

A prospective study of serum soluble CD30 concentration and risk of non-Hodgkin lymphoma

PubMed Central

Lan, Qing; Martinez-Maza, Otoniel; Oken, Martin M.; Hocking, William; Huang, Wen-Yi; Baris, Dalsu; Conde, Betty; Rothman, Nathaniel

2009-01-01

Prediagnostic serum concentration of soluble CD30 (sCD30), a marker for chronic B-cell stimulation, has been associated with increased risk of developing AIDS-related non-Hodgkin lymphoma (NHL) in a recent study of HIV+ patients. To investigate among healthy persons whether serum sCD30 is associated with NHL risk, we carried out a nested case-control study within the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial. There was a strong dose-response relationship between prediagnostic sCD30 concentration and NHL risk among 234 cases and 234 individually matched controls (odds ratio [95% confidence interval] for second, third, and fourth quartiles vs first quartile: 1.4 [0.8-2.6], 2.2 [1.2-4.1], 4.1 [2.2-7.8]; Ptrend < .001), which persisted among cases diagnosed 6 to 10 years after providing a blood sample. Given that a similar relationship has been observed among HIV+ patients, our findings suggest that chronic B-cell stimulation may be an important mechanism involved in B-cell lymphomagenesis among severely immunocompromised and healthy populations alike. PMID:19638620

Merriam's turkey nest survival and factors affecting nest predation by mammals

Treesearch

Chad P. Lehman; Mark A. Rumble; Lester D. Flake; Daniel J. Thompson

2008-01-01

Nest success is an important parameter affecting population fluctuations of wild turkeys (Meleagris gallopavo). Factors influencing mammalian predation on turkey nests are complicated and not well understood. Therefore, we assessed nest hazard risk by testing competing hypotheses of Merriam's turkey (M. g. merriami) nest...

On estimation of time-dependent attributable fraction from population-based case-control studies.

PubMed

Zhao, Wei; Chen, Ying Qing; Hsu, Li

2017-09-01

Population attributable fraction (PAF) is widely used to quantify the disease burden associated with a modifiable exposure in a population. It has been extended to a time-varying measure that provides additional information on when and how the exposure's impact varies over time for cohort studies. However, there is no estimation procedure for PAF using data that are collected from population-based case-control studies, which, because of time and cost efficiency, are commonly used for studying genetic and environmental risk factors of disease incidences. In this article, we show that time-varying PAF is identifiable from a case-control study and develop a novel estimator of PAF. Our estimator combines odds ratio estimates from logistic regression models and density estimates of the risk factor distribution conditional on failure times in cases from a kernel smoother. The proposed estimator is shown to be consistent and asymptotically normal with asymptotic variance that can be estimated empirically from the data. Simulation studies demonstrate that the proposed estimator performs well in finite sample sizes. Finally, the method is illustrated by a population-based case-control study of colorectal cancer. © 2017, The International Biometric Society.

Evaluation of a nested-PCR for mycobacterium tuberculosis detection in blood and urine samples.

PubMed

da Cruz, Heidi Lacerda Alves; de Albuquerque Montenegro, Rosana; de Araújo Lima, Juliana Falcão; da Rocha Poroca, Diogo; da Costa Lima, Juliana Figueirêdo; Maria Lapa Montenegro, Lílian; Crovella, Sergio; Charifker Schindler, Haiana

2011-01-01

The polymerase chain reaction (PCR) and its variations, such as the nested-PCR, have been described as promising techniques for rapid diagnosis of tuberculosis (TB). With the aim of evaluating the usefulness of a nested-PCR method on samples of blood and urine of patients suspected of tuberculosis we analyzed 192 clinical samples, using as a molecular target the insertion element IS6110 specific of M. tuberculosis genome. Nested-PCR method showed higher sensitivity in patients with extrapulmonary tuberculosis (47.8% and 52% in blood and urine) when compared to patients with the pulmonary form of the disease (sensitivity of 29% and 26.9% in blood and urine), regardless of the type of biological sample used. The nested-PCR is a rapid technique that, even if not showing a good sensitivity, should be considered as a helpful tool especially in the extrapulmonary cases or in cases where confirmatory diagnosis is quite difficult to be achieved by routine methods. The performance of PCR-based techniques should be considered and tested in future works on other types of biological specimens besides sputum, like blood and urine, readily obtainable in most cases. The improving of M. tuberculosis nested-PCR detection in TB affected patients will give the possibility of an earlier detection of bacilli thus interrupting the transmission chain of the disease.

Systolic blood pressure variability and lower extremity amputation in a non-elderly population with diabetes.

PubMed

Budiman-Mak, Elly; Epstein, Noam; Brennan, Meghan; Stuck, Rodney; Guihan, Marylou; Huo, Zhiping; Emanuele, Nicholas; Sohn, Min-Woong

2016-04-01

Systolic blood pressure (SBP) variability is emerging as a new risk factor for cardiovascular diseases, diabetic nephropathy, and other atherosclerotic conditions. Our objective is to examine whether it has any prognostic value for lower-extremity amputations. This is a nested case-control study of a cohort of patients with diabetes aged<60 years and treated in the US Department of Veterans Healthcare system in 2003. They were followed over five years for any above-ankle (major) amputations. For each case with a major amputation (event), we randomly selected up to five matched controls based on age, sex, race/ethnicity, and calendar time. SBP variability was computed using three or more blood pressure measures taken during the one-year period before the event. Patients were classified into quartiles according to their SBP variability. The study sample included 1038 cases and 2932 controls. Compared to Quartile 1 (lowest variability), Quartile 2 had 1.4 times (OR=1.44, 95% CI=1.00-2.07) and Quartiles 3 and 4 (highest) had 2.5 times (OR for Quartile 3=2.62, 95% CI=1.85-3.72; OR for Quartile 4=2.50, 95% CI=1.74-3.59) higher risk of major amputation (P for trend<0.001). This gradient relationship held in both normotensive and hypertensive groups as well as for individuals without prior peripheral vascular disease. This is the first study to show a significant graded relationship between SBP variability and risk of major amputation among non-elderly persons with diabetes. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Effects of southern flying squirrels Glaucomys volans on red-cockaded woodpecker Picoides borealis reproductive success

Treesearch

Kevin S. Laves; Susan C. Loeb

1999-01-01

Anecdotal data gathered from many populations suggest that southern flying squirrel (SFS, Glaucomys volans) use of the endangered red-cockaded woodpecker's (RCW, Picoides borealis) nest and roost cavities may negatively affect RCW populations. The authors conducted a controlled experiment to determine the effects of SFS’s on...

RELIANCE ON GEOCODED MATERNAL RESIDENCE: IMPACT ON A POPULATION-BASED CASE-CONTROL STUDY OF AIR QUALITY AND BIRTH DEFECTS

EPA Science Inventory

Introduction: Unbiased geocoding of maternal residence is critical to the success of an ongoing population-based case-control study of exposure to five criteria air pollutants and the risk of selected birth defects in seven Texas counties between 1997 and 2000. The geocoded res...

Independence and interdependence in collective decision making: an agent-based model of nest-site choice by honeybee swarms

PubMed Central

List, Christian; Elsholtz, Christian; Seeley, Thomas D.

2008-01-01

Condorcet's jury theorem shows that when the members of a group have noisy but independent information about what is best for the group as a whole, majority decisions tend to outperform dictatorial ones. When voting is supplemented by communication, however, the resulting interdependencies between decision makers can strengthen or undermine this effect: they can facilitate information pooling, but also amplify errors. We consider an intriguing non-human case of independent information pooling combined with communication: the case of nest-site choice by honeybee (Apis mellifera) swarms. It is empirically well documented that when there are different nest sites that vary in quality, the bees usually choose the best one. We develop a new agent-based model of the bees' decision process and show that its remarkable reliability stems from a particular interplay of independence and interdependence between the bees. PMID:19073474

Physical activity in middle-aged women and hip fracture risk: the UFO study.

PubMed

Englund, U; Nordström, P; Nilsson, J; Bucht, G; Björnstig, U; Hallmans, G; Svensson, O; Pettersson, U

2011-02-01

In a population-based case-control study, we demonstrate that middle-aged women who were active with walking or in different physical spare time activities were at lower risk of later sustaining a hip fracture compared to more sedentary women. In middle-aged women participating in the Umeå Fracture and Osteoporosis (UFO) study, we investigated whether physical activity is associated with a subsequent decreased risk of sustaining a hip fracture. The UFO study is a nested case-control study investigating associations between bone markers, lifestyle, and osteoporotic fractures. We identified 81 female hip fracture cases that had reported lifestyle data before they sustained their fracture. Each case was compared with two female controls who were identified from the same cohort and matched for age and week of reporting data, yielding a total cohort of 237 subjects. Mean age at baseline was 57.2 ± 5.0 years, and mean age at fracture was 65.4 ± 6.4 years. Conditional logistic regression analysis with adjustments for height, weight, smoking, and menopausal status showed that subjects who were regularly active with walking or had a moderate or high frequency of physical spare time activities (i.e. berry/mushroom picking and snow shovelling) were at reduced risk of sustaining a hip fracture (OR 0.14; 95% CI; 0.05-0.53 for walking and OR 0.19; 95% CI; 0.08-0.46, OR 0.17, 95% CI; 0.05-0.64 for moderate and high frequency of spare time activities, respectively) compared to more sedentary women. An active lifestyle in middle age seems to reduce the risk of future hip fracture. Possible mechanisms may include improved muscle strength, coordination, and balance resulting in a decreased risk of falling and perhaps also direct skeletal benefits.

The effect of past antibiotic exposure on diabetes risk

PubMed Central

Boursi, Ben; Mamtani, Ronac; Haynes, Kevin; Yang, Yu-Xiao

2015-01-01

Objective Gut microbiota influence metabolic pathways relevant to the pathogenesis of obesity, insulin-resistance and diabetes. Antibiotic therapy can alter the microbiota and is commonly used in western countries. We sought to evaluate whether past antibiotic exposure increases diabetes risk. Research design and methods We conducted a nested case-control study using a large population-based database from the United Kingdom (UK). Cases were defined as those with incident diagnosis of diabetes. For every case, 4 eligible controls matched on age, sex, practice-site, and duration of follow-up before index-date were selected using incidence-density sampling. Exposure of interest was antibiotic therapy >1 year before index-date. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using conditional logistic regression. The risk was adjusted for body mass index (BMI), smoking, last glucose level and number of infections before index-date, as well as past medical history of coronary artery disease and hyperlipidemia. Results The study included 208,002 diabetic cases and 815,576 matched controls. Exposure to a single antibiotic prescription was not associated with higher adjusted diabetes risk. Treatment with 2–5 antibiotic courses was associated with increase in diabetic risk for penicillin, cephalosporins, macrolides and quinolones with adjusted OR ranging from 1.08 (95%CI 1.05–1.11) for penicillin to 1.15 (95%CI 1.08–1.23) for quinolones. The risk increased with the number of antibiotic courses and reached 1.37 (95%CI 1.19–1.58) for >5 courses of quinolones. There was no association between exposure to anti-virals and anti-fungals and diabetes risk. Conclusions Exposure to certain antibiotic groups increases diabetes risk. PMID:25805893

Association between traditional systemic antipsoriatic drugs and tuberculosis risk in patients with psoriasis with or without psoriatic arthritis: results of a nationwide cohort study from Taiwan.

PubMed

Chen, Yi-Ju; Wu, Chun-Ying; Shen, Jui-Lung; Chen, Tzu-Ting; Chang, Yun-Ting

2013-07-01

Although the link between tuberculosis (TB) and biologics use is well established, the risk of TB among patients with psoriasis exposed to traditional systemic therapies remains elusive. The aim is to investigate the association between traditional systemic therapies and TB among patients with psoriasis. We conducted a retrospective cohort study on the risk of active TB among patients with psoriasis and psoriatic arthritis, using the National Health Insurance Research Database of Taiwan, 1996 through 2008. Standardized incidence ratios of TB were analyzed in comparison with age- and gender-matched general population. Logistic regression was used in a nested case-control analysis to estimate the odds ratios of TB related to exposure to traditional systemic agents during the year before TB development. Among the 81,266 patients in the psoriasis cohort, 497 new active TB cases were identified. The incidence rate of TB was 102 cases per 100,000 person-years among patients with psoriasis (standardized incidence ratio 1.22, 95% confidence interval 1.18-1.33). The risk of TB was higher in patients with severe disease (standardized incidence ratio 1.52, 95% confidence interval 1.46-1.74). To facilitate comparisons with the 497 active TB cases, a total of 1988 matched control subjects were selected for a nested case-control study. Patients taking systemic corticosteroids and nonsteroidal anti-inflammatory drugs were associated with higher incidence of TB, especially frequent users, after adjustment for multiple TB risk factors, drug exposures, hospital visits, and level of urbanization. Stratified analyses of current users and new users of these drugs revealed similar results. Finally, traditional systemic antipsoriatic treatment was not associated with TB on any of the analyses. The National Health Insurance Research Database did not contain information regarding severity of psoriasis, smoking status, alcohol use, diet, laboratory parameters, chest radiograph, or history of recent contact with an individual with TB. Misclassification of disease cannot be ruled out in a registry-based database. The accessibility of health care may be associated with the level of urbanization, which could confound the effect of drugs in multivariate analyses. Severe psoriasis may be associated with an elevated TB risk. Traditional systemic therapies do not seem to be strongly associated with TB occurrence. Copyright © 2012 American Academy of Dermatology, Inc. Published by Mosby, Inc. All rights reserved.

Conservation of the yellow-shouldered blackbird, Agelaius xanthomus, an endangered West Indian species

USGS Publications Warehouse

Wiley, J.W.; Post, W.; Cruz, A.

1991-01-01

The yellow-shouldered blackbird Agelaius xanthomus, endemic to Puerto Rico and Mona Island, is endangered, mainly because of brood parasitism by the shiny cowbird Molothrus bonariensis, which reached Puerto Rico at least 30 years ago. The yellow-shouldered blackbird populations have since declined, about 770?1200 remaining (470?900 on Mona Island) by 1982?1986 compared to a population of about 2400 in 1975. Nearly all nests of blackbirds in most of its habitats are parasitized by cowbirds. This significantly reduces nesting success, but blackbirds have evolved no defenses against brood parasitism. Removal of cowbirds from the yellow-shouldered blackbird nesting grounds, modeled after similar programmes for the brown-headed cowbird Molothrus ater on Kirtland's warbler Dendroica kirtlandii nesting areas, significantly increased blackbird production. Blackbirds readily accept nest boxes, and breeding populations can be established in otherwise unusable sites and can be concentrated in mangrove habitats, were they are more easily protected by cowbird removal. Furthermore, yellow-shouldered blackbird pairs using cavities, including nest boxes, fledged more young per nest than pairs using open nests.

Osprey distribution, abundance, and status in western North America: III. The Baja California and Gulf of California population

USGS Publications Warehouse

Henny, C.J.; Anderson, D.W.

1979-01-01

-An estimated 810 ? 55 pairs (minimum estimate) of ospreys (Pandion haliaetus) were nesting in the study area during our survey (24 March-l April 1977). Approximately 174 pairs nested along the Pacific side of Baja California, 255 pairs along the gulf side, 187 pairs on the Midriff Islands, and 194 pairs in coastal Sonora and Sinaloa. Most nested on cliffs adjacent to the sea (59%); some nested on cactus in flat terrain (26%). Seven per cent nested on the ground, three percent nested in mangroves and other trees in the southern portion of the study area,.and four percent nested on man-made structures. The extreme northwestern Baja California population that was extirpated early in this century has not recovered. However, several populations immediately to the south along the Pacific Coast now appear stationary. Pesticide residues in osprey eggs from Mexico were among the lowest reported for the species in North America.

Burrowing Owl (Speotyto cunicularia) monitoring and management activities in Manitoba, 1987-1996

Treesearch

Ken D. De Smet

1997-01-01

Monitoring of Burrowing Owl (Speotyto cunicularia) populations in Manitoba from 1987-1996 revealed a continuous population decline from 34 known nesting pairs to only one. Management activities are discussed including public awareness programs, reintroductions, habitat protection and provision of artificial nest burrows. Nest reuse in consecutive...

Nest survival of clay-colored and vesper sparrows in relation to woodland edge in mixed-grass prairies

USGS Publications Warehouse

Grant, T.A.; Madden, E.M.; Shaffer, T.L.; Pietz, P.J.; Berkey, G.B.; Kadrmas, N.J.

2006-01-01

The quantity and quality of northern mixed-grass prairie continues to decline because of conversion to agriculture, invasion of woody and exotic plants, and disruption of important ecological processes that shape grasslands. Declines in grassland bird populations in North Dakota, USA, have coincided with these largely anthropogenic alterations to prairie habitat. In grasslands of north-central and northwestern North Dakota, woody plants have increased due primarily to fire suppression, extirpation of bison (Bos bison), and widescale planting of tree shelter belts. In northern grasslands, effects of woody vegetation on survival of grassland birds are poorly understood, and conclusions are based mainly on studies conducted outside the region. We examined nest survival of clay-colored sparrows (Spizella pallida) and vesper sparrows (Pooecetes gramineus) relative to the distance nests were located from aspen (Populus tremuloides,) woodland edges and relative to other habitat features near the nest. Clay-colored and vesper sparrow nest survival was higher for nests located near woodland edges, nests with greater cover of Kentucky bluegrass (Poa pratensis), and nests more concealed by vegetation. Vesper sparrow nest survival increased as the percent cover of tall shrubs near the nest increased. Based on video-camera data, the 13-lined ground squirrel (Spermophilus tridecemlineatus,) was the most common predator of sparrow eggs and young. Thirteen-lined ground squirrels were more common far from woodland edges than near, and this pattern may, in part, explain clay-colored and vesper sparrow nest survival in relation to woodland edges. In contrast to our results, studies conducted in other grassland systems generally report lower nest survival for grassland birds nesting near trees and shrubs. This disparity in results demonstrates the need to identify specific nest predators and their distributions with respect to important habitat features because these data can be important in explaining-and perhaps predicting-patterns of nest predation.

Detection of Celiac Disease and Lymphocytic Enteropathy by Parallel Serology and Histopathology in a Population-Based Study

PubMed Central

Walker, Marjorie M.; Murray, Joseph A.; Ronkainen, Jukka; Aro, Pertti; Storskrubb, Tom; D’Amato, Mauro; Lahr, Brian; Talley, Nicholas J.; Agreus, Lars

2010-01-01

Background & Aims Although serological analysis is used in diagnosis of celiac disease, histopathology is considered most reliable. We performed a prospective study to determine the clinical, pathological and serological spectrum of celiac disease in a general population (Kalixanda study). Methods A random sample of an adult general population (n=1000) was analyzed by upper endoscopy, duodenal biopsy, and serological analysis of tissue transglutaminase (tTg) levels; endomysial antibody (EMA) levels were analyzed in samples that were tTg+. The cutoff values for diagnosis of celiac disease were villous atrophy with 40 intraepithelial lymphocytes (IELs)/100 enterocytes (ECs). Results Samples from 33 subjects were tTg+ and 16 were EMA+. Histological analysis identified 7/1000 subjects (0.7%) with celiac disease; all were tTg+ and 6/7 were EMA+. Another 26 subjects were tTg+ (7/26 EMA+). This was addressed by a second quantitative pathology study, (nested case-control design) using a threshold of 25 IELS/100 ECs. In this analysis, all 13 samples that were tTg+ and EMA+ had ≥25 IELs/100ECs. In total, 16 subjects (1.6%) had serological and histological evidence of gluten-sensitive enteropathy. IELs were quantified in duodenal biopsy samples from seronegative individuals (n=500); 19 (3.8%) had >25 IELs and lymphocytic duodenosis (LD). Conclusions Measurement of ≥25 IELs/100 ECs correlated with serological indicators of celiac disease; a higher IEL threshold could miss 50% of cases. Quantification of tTg is a sensitive test for celiac disease; diagnosis can be confirmed by observation of ≥25 IELs/100ECs in duodenal biopsies. Lymphocytic enteropathy (celiac disease and LD) is common in the population (5.4%). PMID:20398668

Using heronry birds to monitor urbanization impacts: a case study of painted stork Mycteria leucocephala nesting in the Delhi Zoo, India.

PubMed

Urfi, Abdul Jamil

2010-03-01

Although urbanization is a frequently cited cause of biodiversity loss (Czech and Krausman 1997) our understanding about urban ecology is severely limited (Marzluff et al. 2001). Birds are popular bio-indicators of environmental change because they are ecologically versatile, their populations as well as select fitness parameters can be conveniently monitored, often with the voluntary involvement of local nature enthusiasts across large geographical scales, and their presence/absence in a particular area is consequential (Bibby et al. 1992; Urfi 2004). In India, while several studies have focused on changes in bird populations and distributions in natural habitats (Urfi et al. 2005), very few have actually attempted to study either the impacts of urbanization on birds or how different species have adjusted to environmental change. However, many Indian cities offer foraging and nesting habitat for birds, especially colonial waterbirds such as stork, ibis, spoonbill, heron, egret, cormorant, and spoonbill. Some notable examples in this regard are Piele Gardens in Bhavnagar city (Parasharya and Naik 1990), Karanji Tank in Mysore (Jamgaonkar et al. 1994) and the National Zoological Park (hence forth Delhi Zoo) in India's capital city New Delhi (Urfi 1997). In this article, I focus on the opportunities for meaningful ecological research offered by the wild waterbirds nesting in the Delhi Zoo premises and discuss the significance for initiating novel, long term conservation monitoring programs, involving volunteers and bird watchers, to create data bases that will be useful for understanding urbanization and climate change impacts on biodiversity.

Population dynamics of mallards breeding in eastern Washington

USGS Publications Warehouse

Dugger, Bruce D.; Coluccy, John M.; Dugger, Katie M.; Fox, Trevor T.; Kraege, Donald K.; Petrie, Mark J.

2016-01-01

Variation in regional population trends for mallards breeding in the western United States indicates that additional research into factors that influence demographics could contribute to management and understanding the population demographics of mallards across North America. We estimated breeding incidence and adult female, nest, and brood survival in eastern Washington in 2006 and 2007 by monitoring female mallards with radio telemetry and tested how those parameters were influenced by study year (2006 vs. 2007), landscape type (agricultural vs. natural), and age (second year [SY] vs. after second year [ASY]). We also investigated the effects of female body condition and capture date on breeding incidence, and nest initiation date and hatch date on nest and brood survival, respectively. We included population parameters in a stage-based demographic model and conducted a perturbation analysis to identify which vital rates were most influential on population growth rate (λ). Adult female survival was best modeled with a constant weekly survival rate (0.994, SE = 0.003). Breeding incidence differed between years and was higher for birds in better body condition. Nest survival was higher for ASY females (0.276, SE = 0.118) than SY females (0.066, SE = 0.052), and higher on publicly managed lands (0.383, SE = 0.212) than agricultural (0.114, SE = 0.058) landscapes. Brood survival was best modeled with a constant rate for the 7-week monitoring period (0.50, SE = 0.155). The single variable having the greatest influence on λ was non-breeding season survival, but the combination of parameters from the breeding grounds explained a greater percent of the variance in λ. Mallard population growth rate was most sensitive to changes in non-breeding survival, nest success, brood survival, and breeding incidence. Future management decisions should focus on activities that improve these vital rates if managers want to increase the production of mallards in eastern Washington.

Diablotin Pterodroma hasitata: a biography of the endangered Black-capped Petrel

USGS Publications Warehouse

Simons, Theodore R.; Lee, David S.; Haney, J. Christopher

2013-01-01

Our findings are in accord with the recent decision by the US Fish and Wildlife Service (USFWS) to evaluate the need for additional protection of the species and the primary foraging habitat off the southeastern United States under the Endangered Species Act (USFWS 2012). Additional conservation measures and research strategies that warrant further consideration include (1) protection, monitoring, and management of known breeding populations and nesting habitat in the Dominican Republic and Haiti through controlling predators, installing artificial nest burrows in appropriate sites and hiring local wardens at breeding sites during the nesting season; (2) local and regional training, education and public awareness (e.g. Blanchard & Nettleship 1992); (3) restoration of the original common name Diablotin to common usage to promote the historical and cultural importance of this species; (4) studies to determine the distribution and genetic variability in the remaining populations; and (5) studies of satellite-tagged birds to assess their seasonal and geographic use of pelagic habitats.

Use of a nested PCR-enzyme immunoassay with an internal control to detect Chlamydophila psittaci in turkeys

PubMed Central

Van Loock, Marnix; Verminnen, Kristel; Messmer, Trudy O; Volckaert, Guido; Goddeeris, Bruno M; Vanrompay, Daisy

2005-01-01

Background Laboratory diagnosis of Chlamydophila psittaci, an important turkey respiratory pathogen, is difficult. To facilitate the diagnosis, a nested PCR-enzyme immunoassay (PCR-EIA) was developed to detect the Cp. psittaci outer membrane protein A (ompA) gene in pharyngeal swabs. Methods The fluorescein-biotin labelled PCR products were immobilized on streptavidin-coated microtiter plates and detected with anti-fluorescein peroxidase conjugate and a colorimetric substrate. An internal inhibition control was included to rule out the presence of inhibitors of DNA amplification. The diagnostic value of the ompA nested PCR-EIA in comparison to cell culture and a 16S-rRNA based nested PCR was assessed in pharyngeal turkey swabs from 10 different farms experiencing respiratory disease. Results The sensitivity of the nested PCR-EIA was established at 0.1 infection forming units (IFU). Specificity was 100%. The ompA nested PCR-EIA was more sensitive than the 16S-rRNA based nested PCR and isolation, revealing 105 out of 200 (52.5%) positives against 13 and 74 for the latter two tests, respectively. Twenty-nine (23.8%) out of 122 ompA PCR-EIA negatives showed the presence of inhibitors of DNA amplification, although 27 of them became positive after diluting (1/10) the specimens in PCR buffer or after phenol-chloroform extraction and subsequent ethanol precipitation. Conclusion The present study stresses the need for an internal control to confirm PCR true-negatives and demonstrates the high prevalence of chlamydiosis in Belgian turkeys and its potential zoonotic risk. The ompA nested PCR-EIA described here is a rapid, highly sensitive and specific diagnostic assay and will help to facilitate the diagnosis of Cp. psittaci infections in both poultry and man. PMID:16185353

Serum brain-derived neurotrophic factor levels in subjects with major depressive disorder with previous suicide attempt: A population-based study.

PubMed

Pedrotti Moreira, Fernanda; Borges, Cristiane Jackson; Wiener, Carolina David; da Silva, Paula Moraes; Portela, Luis Valmor; Lara, Diogo R; da Silva, Ricardo Azevedo; de Mattos Souza, Luciano Dias; Jansen, Karen; Oses, Jean Pierre

2018-04-01

Major depressive disorders (MDD) and suicide are significant public health concerns. Recent studies have been demonstrated that alterations in Brain Derived Neurotrophic Factor (BDNF) can be associated with this psychiatric disorders, MDD and suicide. Thus, the aim of this study was to evaluate differences in serum levels in individuals with MDD and with or without suicide attempt (SA), from a population-based sample. This was a paired cross-sectional study nested in a population-based study. The psychopathology screen was performed with the Mini-International Neuropsychiatric Interview (MINI). The total population of the sample consisted of 147 subjects distributed in three groups: 49 healthy controls, 49 subjects with MDD and 49 subjects with MDD and SA (MDD + SA). The BDNF serum levels were significantly reduced in subjects with MDD and MDD + SA compared to the healthy controls. However, there were no significant differences between the MDD and MDD + SA groups with respect to BDNF serum levels. These results suggest that SA did not interfere in the serum levels of BDNF, indicating that this neurotrophin may be related to the diagnosis of MDD and not to suicide attempt. Copyright © 2017 Elsevier B.V. All rights reserved.

Re-colonization by common eiders Somateria mollissima in the Aleutian Archipelago following removal of introduced arctic foxes Vulpes lagopus

USGS Publications Warehouse

Petersen, Margaret R.; Sonsthagen, Sarah A.; Sexson, Matthew G.

2015-01-01

Islands provide refuges for populations of many species where they find safety from predators, but the introduction of predators frequently results in elimination or dramatic reductions in island-dwelling organisms. When predators are removed, re-colonization for some species occurs naturally, and inter-island phylogeographic relationships and current movement patterns can illuminate processes of colonization. We studied a case of re-colonization of common eiders Somateria mollissima following removal of introduced arctic foxes Vulpes lagopus in the Aleutian Archipelago, Alaska. We expected common eiders to resume nesting on islands cleared of foxes and to re-colonize from nearby islets, islands, and island groups. We thus expected common eiders to show limited genetic structure indicative of extensive mixing among island populations. Satellite telemetry was used to record current movement patterns of female common eiders from six islands across three island groups. We collected genetic data from these and other nesting common eiders at 14 microsatellite loci and the mitochondrial DNA control region to examine population genetic structure, historical fluctuations in population demography, and gene flow. Our results suggest recent interchange among islands. Analysis of microsatellite data supports satellite telemetry data of increased dispersal of common eiders to nearby areas and little between island groups. Although evidence from mtDNA is suggestive of female dispersal among island groups, gene flow is insufficient to account for recolonization and rapid population growth. Instead, near-by remnant populations of common eiders contributed substantially to population expansion, without which re-colonization would have likely occurred at a much lower rate. Genetic and morphometric data of common eiders within one island group two and three decades after re-colonization suggests reduced movement of eiders among islands and little movement between island groups after populations were re-established. We predict that re-colonization of an island group where all common eiders are extirpated could take decades.

Landscapes for Energy and Wildlife: Conservation Prioritization for Golden Eagles across Large Spatial Scales

PubMed Central

Tack, Jason D.; Fedy, Bradley C.

2015-01-01

Proactive conservation planning for species requires the identification of important spatial attributes across ecologically relevant scales in a model-based framework. However, it is often difficult to develop predictive models, as the explanatory data required for model development across regional management scales is rarely available. Golden eagles are a large-ranging predator of conservation concern in the United States that may be negatively affected by wind energy development. Thus, identifying landscapes least likely to pose conflict between eagles and wind development via shared space prior to development will be critical for conserving populations in the face of imposing development. We used publically available data on golden eagle nests to generate predictive models of golden eagle nesting sites in Wyoming, USA, using a suite of environmental and anthropogenic variables. By overlaying predictive models of golden eagle nesting habitat with wind energy resource maps, we highlight areas of potential conflict among eagle nesting habitat and wind development. However, our results suggest that wind potential and the relative probability of golden eagle nesting are not necessarily spatially correlated. Indeed, the majority of our sample frame includes areas with disparate predictions between suitable nesting habitat and potential for developing wind energy resources. Map predictions cannot replace on-the-ground monitoring for potential risk of wind turbines on wildlife populations, though they provide industry and managers a useful framework to first assess potential development. PMID:26262876

Landscapes for energy and wildlife: conservation prioritization for golden eagles across large spatial scales

USGS Publications Warehouse

Tack, Jason D.; Fedy, Bradley C.

2015-01-01

Proactive conservation planning for species requires the identification of important spatial attributes across ecologically relevant scales in a model-based framework. However, it is often difficult to develop predictive models, as the explanatory data required for model development across regional management scales is rarely available. Golden eagles are a large-ranging predator of conservation concern in the United States that may be negatively affected by wind energy development. Thus, identifying landscapes least likely to pose conflict between eagles and wind development via shared space prior to development will be critical for conserving populations in the face of imposing development. We used publically available data on golden eagle nests to generate predictive models of golden eagle nesting sites in Wyoming, USA, using a suite of environmental and anthropogenic variables. By overlaying predictive models of golden eagle nesting habitat with wind energy resource maps, we highlight areas of potential conflict among eagle nesting habitat and wind development. However, our results suggest that wind potential and the relative probability of golden eagle nesting are not necessarily spatially correlated. Indeed, the majority of our sample frame includes areas with disparate predictions between suitable nesting habitat and potential for developing wind energy resources. Map predictions cannot replace on-the-ground monitoring for potential risk of wind turbines on wildlife populations, though they provide industry and managers a useful framework to first assess potential development.

Nesting and foraging behavior of red-winged blackbirds in stormwater wetlands

USGS Publications Warehouse

Sparling, D.W.; Eisemann, J.; Kuenzel, W.

2007-01-01

Stormwater wetlands are a common part of urban and suburban landscapes. These constructed wetlands provide first-order treatment of effluent from roads, parking lots, lawns and other surfaces. They also provide habitat for wetland-associated birds. Thus, there is a concern that birds may be attracted to potentially toxic habitats. This study assesses nesting success and forging behavior of Red-winged Blackbirds (Agelaius phoeniceus) in retention stormwater wetlands based on drainage type. Drainage categories included residential, commercial, and highway sites. Commercial sites had the lowest nesting success and the lowest diversity of invertebrate foods. Mean nest success values for all three types of wetlands, especially for highway drainages, were comparable to published values from natural wetlands. Over two years of study highway ponds collectively served as source populations whereas residential and commercial sites were population sinks in one year and sources in the other. Red-wings using highway sites had the highest foraging efficiency as determined by the frequency and duration of forays. Residential sites had the greatest human disturbance and generally had intermediate-quality habitat and nesting success. We conclude that while stormwater wetlands collect run off and accompanying pollutants, they can still be valuable habitats for nesting birds in urban and suburban areas. We recommend a few management strategies that can increase avian use of these habitats. ?? Springer Science+Business Media, LLC 2007.

Landscapes for Energy and Wildlife: Conservation Prioritization for Golden Eagles across Large Spatial Scales.

PubMed

Tack, Jason D; Fedy, Bradley C

2015-01-01

Proactive conservation planning for species requires the identification of important spatial attributes across ecologically relevant scales in a model-based framework. However, it is often difficult to develop predictive models, as the explanatory data required for model development across regional management scales is rarely available. Golden eagles are a large-ranging predator of conservation concern in the United States that may be negatively affected by wind energy development. Thus, identifying landscapes least likely to pose conflict between eagles and wind development via shared space prior to development will be critical for conserving populations in the face of imposing development. We used publically available data on golden eagle nests to generate predictive models of golden eagle nesting sites in Wyoming, USA, using a suite of environmental and anthropogenic variables. By overlaying predictive models of golden eagle nesting habitat with wind energy resource maps, we highlight areas of potential conflict among eagle nesting habitat and wind development. However, our results suggest that wind potential and the relative probability of golden eagle nesting are not necessarily spatially correlated. Indeed, the majority of our sample frame includes areas with disparate predictions between suitable nesting habitat and potential for developing wind energy resources. Map predictions cannot replace on-the-ground monitoring for potential risk of wind turbines on wildlife populations, though they provide industry and managers a useful framework to first assess potential development.

Vitamin D and the risk of preeclampsia--a nested case-control study.

PubMed

Gidlöf, Sebastian; Silva, Aldo T; Gustafsson, Sven; Lindqvist, Pelle G

2015-08-01

We aimed to determine the relation between vitamin D deficiency in early pregnancy and preeclampsia. In a nested case-control study of 2496 pregnant women, we identified 39 women who developed preeclampsia and 120 non-preeclamptic controls. Blood was sampled in 12th gestational week and analyzed for serum vitamin D. Vitamin D levels were similar in women who developed preeclampsia, 52.2 ± 20.5 nmol/L, and controls, 48.6 ± 20.5 nmol/L, p = 0.3. In addition, vitamin D deficiency (<50 nmol/L) was found in a similar proportion of control group (51.7%) as those with severe preeclampsia (41.2%). Women with vitamin D deficiency were 3 cm shorter than those with normal vitamin D levels (p = 0.002). Our data do not support the hypothesis that vitamin D deficiency in early pregnancy is associated with preeclampsia, but we cannot rule out a relation later in gestation. © 2015 Nordic Federation of Societies of Obstetrics and Gynecology.

Population size and trends for nesting ospreys in northwestern Mexico: Region-wide surveys, 1977, 1992/1993 and 2006

USGS Publications Warehouse

Henny, Charles J.; Anderson, Daniel W.; Vera, Aradit Castellanos; Carton, Jean-Luc E.

2007-01-01

We used a double-sampling technique (air plus ground survey) in 2006, with partial double coverage, to estimate the present size of the osprey (Pandion haliaetus) nesting population in northwestern Mexico. With the exception of Natividad, Cedros, and San Benito Islands along the Pacific Coast of Baja California, all three excluded from our coverage in 2006 due to fog, this survey was a repeat of previous surveys conducted by us with the same protocol in 1977 and 1992/1993 (Baja California surveyed in 1992, Sonora and Sinaloa 1993), allowing for estimates of regional population trends. Population estimates at the 'time of aerial survey' include those nesting, but missed from the air. The population estimate for our coverage area in 2006 was 1,343 nesting pairs, or an 81% increase since 1977, but only a 3% increase since 1992/1993. The population on the Gulf side of Baja California generally remained stable during the three surveys (255, 236 and 252 pairs, respectively). The overall Midriff Islands population remained similar from 1992/1993 (308 pairs) to 2006 (289 pairs), but with notable population changes on the largest two islands (Isla Angel de la Guarda: 45 to 105 pairs [+ 60 pairs]; Isla Tiburon: 164 to 109 pairs [- 55 pairs, or -34%]). The estimated osprey population on the Sonora mainland decreased in a manner similar to adjacent Isla Tiburon, i.e., by 26%, from 214 pairs in 1993 to 158 pairs in 2006. In contrast, the population in Sinaloa, which had increased by 150% between 1977 and 1993, grew again by 58% between 1993 and 2006, from 180 to 285 pairs. Our survey confirmed previously described patterns of rapid population changes at a local level, coupled with apparent shifts in spatial distribution. The large ground nesting population that until recently nested on two islands in San Ignacio Lagoon was no longer present on the islands in 2006, but an equivalent number of pairs were found to the north and south of the lagoon, nesting in small towns and along adjoining power-lines, with no overall change in population size for that general area (198 pairs in 1992; 199 in 2006). Use of artificial nesting structures was 4.3% in 1977 and 6.2% in 1992/1993, but jumped to 26.4% in 2006. Use of power poles poses a risk of electrocution to ospreys as well as causes power outages and fires; modification of power poles to safely accommodate osprey nests has been successful in many countries.

Cutaneous beta human papillomaviruses and the development of male external genital lesions: A case-control study nested within the HIM Study.

PubMed

Pierce Campbell, Christine M; Gheit, Tarik; Tommasino, Massimo; Lin, Hui-Yi; Torres, B Nelson; Messina, Jane L; Stoler, Mark H; Rollison, Dana E; Sirak, Bradley A; Abrahamsen, Martha; Carvalho da Silva, Roberto J; Sichero, Laura; Villa, Luisa L; Lazcano-Ponce, Eduardo; Giuliano, Anna R

2016-10-01

Cutaneous human papillomaviruses (HPVs) increase the risk of non-melanoma skin cancer in sun-exposed skin. We examined the role of beta-HPV in the development of male external genital lesions (EGLs), a sun-unexposed site. In this nested case-control study (67 men with pathologically-confirmed EGLs and 134 controls), exfoliated cells collected from the surface of lesions and normal genital skin 0, 6, and 12 months preceding EGL development were tested for beta-HPV DNA using a type-specific multiplex genotyping assay. Beta-HPV prevalence was estimated and conditional logistic regression was used to evaluate the association with condyloma, the most common EGL. While beta-HPV prevalence among controls remained stable, the prevalence among cases was lowest on the surface of lesion. Detecting beta-HPV on the normal genital skin was not associated with the presence or development of condyloma. Cutaneous beta-HPV does not appear to be contributing to pathogenesis in male genital skin. Copyright © 2016. Published by Elsevier Inc.

Factors that influence vital rates of Seaside and Saltmarsh sparrows in coastal New Jersey, USA

PubMed Central

Roberts, Samuel G.; Longenecker, Rebecca A.; Etterson, Matthew A.; Ruskin, Katharine J.; Elphick, Chris S.; Olsen, Brian J.; Shriver, W. Gregory

2018-01-01

As saltmarsh habitat continues to disappear, understanding the factors that influence saltmarsh breeding bird population dynamics is an important step for the conservation of these declining species. Using five years (2011 – 2015) of demographic data, we evaluated and compared Seaside (Ammodramus maritimus) and Saltmarsh (A. caudacutus) sparrow apparent adult survival and nest survival at the Edwin B. Forsythe National Wildlife Refuge, New Jersey, USA. We determined the effect of site management history (unditched vs. ditched marsh) on adult and nest survival to aid in prioritizing future management or restoration actions. Seaside Sparrow apparent adult survival (61.6%, 95% CI: 52.5 – 70.0%) averaged >1.5 times greater than Saltmarsh Sparrow apparent adult survival (39.9%, 95% CI: 34.0 – 46.2%). Nest survival and predation and flooding rates did not differ between species, and predation was the primary cause of failure for both species. Apparent adult survival and nest survival did not differ between unditched and ditched marshes for either species, indicating that marsh ditching history may not affect breeding habitat quality for these species. With predation as the primary cause of nest failure for both species in New Jersey, we suggest that future research should focus on identification of predator communities in salt marshes and the potential for implementing predator-control programs to limit population declines. PMID:29479129

User-only design to assess drug effectiveness in clinical practice: application to bisphosphonates and secondary prevention of fractures.

PubMed

Corrao, Giovanni; Ghirardi, Arianna; Segafredo, Giulia; Zambon, Antonella; Della Vedova, Gianluca; Lapi, Francesco; Cipriani, Francesco; Caputi, Achille; Vaccheri, Alberto; Gregori, Dario; Gesuita, Rosaria; Vestri, Annarita; Staniscia, Tommaso; Mazzaglia, Giampiero; Di Bari, Mauro

2014-08-01

Different strategies applicable to control for confounding by indication in observational studies were compared in a large population-based study regarding the effect of bisphosphonates (BPs) for secondary prevention of fractures. The cohort was drawn from healthcare utilization databases of 13 Italian territorial units. Patients aged 55 years or more who were hospitalized for fracture during 2003-2005 entered into the cohort. A nested case-control design was used to compare BPs use in cohort members who did (cases) and who did not experience (controls) a new fracture until 2007 (outcome). Three designs were employed: conventional-matching (D1 ), propensity score-matching (D2 ), and user-only (D3 ) designs. They differed for (i) cohort composition, restricted to patients who received BPs straight after cohort entry (D3 ); (ii) using propensity score for case-control matching (D2 ); and (iii) compared groups of BPs users versus no users (D1 and D2 ) and long-term versus short-term users (D3 ). Bisphosphonate users had odds ratios (95% confidence interval) of 1.20 (1.01 to 1.44) and 0.95 (0.74 to 1.24) by applying D1 and D2 designs, respectively. Statistical evidence that long-term BPs use protects the outcome onset with respect to short-term use was observed for user-only design (D3 ) being the corresponding odds ratio (95% confidence interval) 0.64 (0.44 to 0.93). User-only design yielded closer results to those seen in RCTs. This approach is one possible strategy to account for confounding by indication. Copyright © 2014 John Wiley & Sons, Ltd.

The risk of childhood autism among second-generation migrants in Finland: a case-control study.

PubMed

Lehti, Venla; Hinkka-Yli-Salomäki, Susanna; Cheslack-Postava, Keely; Gissler, Mika; Brown, Alan S; Sourander, Andre

2013-10-19

Studying second-generation immigrants can help in identifying genetic or environmental risk factors for childhood autism. Most previous studies have focused on maternal region of birth and showed inconsistent results. No previous study has been conducted in Finland. The study was a nested case-control study based on a national birth cohort. Children born in 1987-2005 and diagnosed with childhood autism by the year 2007 were identified from the Finnish Hospital Discharge Register. Controls were selected from the Finnish Medical Birth Register. Information on maternal and paternal country of birth and mother tongue was collected from the Finnish Central Population Register. There were 1132 cases and 4515 matched controls. The statistical test used was conditional logistic regression analysis. Compared with children with two Finnish parents, the risk of childhood autism was increased for those whose parents are both immigrants (adjusted odds ratio [aOR] 1.8, 95% confidence interval [CI] 1.2-2.7) and for those with only an immigrant mother (aOR 1.8, 95% CI 1.2-2.7), but not for those with only an immigrant father. The risk was increased for those with a mother born in the former Soviet Union or Yugoslavia and for those with a mother or a father born in Asia. Specific parental countries of birth associated with an increased risk were the former Soviet Union, the former Yugoslavia and Vietnam. In Finland, children who are born to immigrant mothers with or without an immigrant partner, have an increased risk of childhood autism. The risk varies with immigrant parents' region of birth. The findings may help in identifying possible risk factors, which can be examined in future studies.

Landscape heterogeneity drives intra-population niche variation and reproduction in an arctic top predator

PubMed Central

L'Hérault, Vincent; Franke, Alastair; Lecomte, Nicolas; Alogut, Adam; Bêty, Joël

2013-01-01

While intra-population variability in resource use is ubiquitous, little is known of how this measure of niche diversity varies in space and its role in population dynamics. Here we examined how heterogeneous breeding environments can structure intra-population niche variation in both resource use and reproductive output. We investigated intra-population niche variation in the Arctic tundra ecosystem, studying peregrine falcon (Falco peregrinus tundrius, White) breeding within a terrestrial-marine gradient near Rankin Inlet, Nunavut, Canada. Using stable isotope analysis, we found that intra-population niches varied at the individual level; we examined within-nest and among-nest variation, though only the latter varied along the terrestrial-marine gradient (i.e., increased among-nest variability among birds nesting within the marine environment, indicating higher degree of specialization). Terrestrial prey species (small herbivores and insectivores) were consumed by virtually all falcons. Falcons nesting within the marine environment made use of marine prey (sea birds), but depended heavily on terrestrial prey (up to 90% of the diet). Using 28-years of peregrine falcon nesting data, we found a positive relationship between the proportion of terrestrial habitat surrounding nest sites and annual nestling production, but no relationship with the likelihood of successfully rearing at least one nestling reaching 25 days old. Annually, successful inland breeders raised 0.47 more young on average compared to offshore breeders, which yields potential fitness consequences for this long-living species. The analyses of niche and reproductive success suggest a potential breeding cost for accessing distant terrestrial prey, perhaps due to additional traveling costs, for those individuals with marine nest site locations. Our study indicates how landscape heterogeneity can generate proximate (niche variation) and ultimate (reproduction) consequences on a population of generalist predator. We also show that within-individual and among-individual variation are not mutually exclusive, but can simultaneously arise and structure intra-population niche variation. PMID:24101979

Climate change impacts on leatherback turtle pelagic habitat in the Southeast Pacific

NASA Astrophysics Data System (ADS)

Willis-Norton, Ellen; Hazen, Elliott L.; Fossette, Sabrina; Shillinger, George; Rykaczewski, Ryan R.; Foley, David G.; Dunne, John P.; Bograd, Steven J.

2015-03-01

Eastern Pacific populations of the leatherback turtle (Dermochelys coriacea) have declined by over 90% during the past three decades. The decline is primarily attributed to human pressures, including unsustainable egg harvest, development on nesting beaches, and by-catch mortality. In particular, the effects of climate change may impose additional stresses upon already threatened leatherback populations. This study analyzes how the pelagic habitat of Eastern Pacific leatherbacks may be affected by climate change over the next century. This population adheres to a persistent migration pattern; following nesting at Playa Grande, Costa Rica, individuals move rapidly through equatorial currents and into foraging habitat within the oligotrophic South Pacific Gyre. Forty-six nesting females were fitted with satellite tags. Based on the turtle positions, ten environmental variables were sampled along the tracks. Presence/absence habitat models were created to determine the oceanographic characteristics of the preferred turtle habitat. Core pelagic habitat was characterized by relatively low sea surface temperatures and chlorophyll-a. Based on these habitat models, we predicted habitat change using output from the Geophysical Fluid Dynamics Laboratory prototype Earth System Model under the Special Report on Emissions Scenario A2 (business-as-usual). Although the model predicted both habitat losses and gains throughout the region, we estimated that overall the core pelagic habitat of the Eastern Pacific leatherback population will decline by approximately 15% within the next century. This habitat modification might increase pressure on a critically endangered population, possibly forcing distributional shifts, behavioral changes, or even extinction.

Raptors of the Hanford Site and nearby areas of southcentral Washington

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fitzner, R.E.; Rickard, W.H.; Cadwell, L.L.

1981-05-01

This report is concerned with the birds of prey which use the Hanford Site not only during the nesting season but throughout the year. An ecological treatment of five nesting owls (great horned, long-eared, short-eared, barn and burrowing) and five nesting hawks (marsh hawk, red-tailed hawk, Swainson's hawk, prairie falcon and American kestrel) is provided and supportive information on non-nesting species is presented. Factors which control raptor densities and population dynamics throughout all seasons of the year are discussed. Information is also provided for raptors from other areas of southcentral Washington in order to yield a comprehensive picture of howmore » the Hanford Site fits in with regional bird of prey populations. The following were the objectives of this study: (1) to determine the numbers of birds of prey nesting on the Hanford Site, (2) to document the reproductive chronology of each nesting raptor species, (3) to provide analyses of food habits of birds of prey on the Hanford Site coupled with prey abundance data, (4) to determine the productivity of the dominant large birds of prey on the Hanford Site, (5) to determine the distribution and land use patterns of all raptors on the Hanford Site, (6) to determine the kinds and relative abundance of non-nesting raptors on the Hanford Site and adjacent areas of southcentral Washington (7) to document present land use practices on the Hanford Site and their effects on raptors, (8) to document radionuclide levels in birds of prey on the Hanford Site, and (9) to determine the role of birds of prey in radioecological monitoring.« less

Estimating raptor nesting success: old and new approaches

USGS Publications Warehouse

Brown, Jessi L.; Steenhof, Karen; Kochert, Michael N.; Bond, Laura

2013-01-01

Studies of nesting success can be valuable in assessing the status of raptor populations, but differing monitoring protocols can present unique challenges when comparing populations of different species across time or geographic areas. We used large datasets from long-term studies of 3 raptor species to compare estimates of apparent nest success (ANS, the ratio of successful to total number of nesting attempts), Mayfield nesting success, and the logistic-exposure model of nest survival. Golden eagles (Aquila chrysaetos), prairie falcons (Falco mexicanus), and American kestrels (F. sparverius) differ in their breeding biology and the methods often used to monitor their reproduction. Mayfield and logistic-exposure models generated similar estimates of nesting success with similar levels of precision. Apparent nest success overestimated nesting success and was particularly sensitive to inclusion of nesting attempts discovered late in the nesting season. Thus, the ANS estimator is inappropriate when exact point estimates are required, especially when most raptor pairs cannot be located before or soon after laying eggs. However, ANS may be sufficient to assess long-term trends of species in which nesting attempts are highly detectable.

A case-control study to assess the impact of mammographic density on breast cancer risk in women aged 40-49 at intermediate familial risk.

PubMed

Assi, Valentina; Massat, Nathalie J; Thomas, Susan; MacKay, James; Warwick, Jane; Kataoka, Masako; Warsi, Iqbal; Brentnall, Adam; Warren, Ruth; Duffy, Stephen W

2015-05-15

Mammographic density is a strong risk factor for breast cancer, but its potential application in risk management is not clear, partly due to uncertainties about its interaction with other breast cancer risk factors. We aimed to quantify the impact of mammographic density on breast cancer risk in women aged 40-49 at intermediate familial risk of breast cancer (average lifetime risk of 23%), in particular in premenopausal women, and to investigate its relationship with other breast cancer risk factors in this population. We present the results from a case-control study nested with the FH01 cohort study of 6,710 women mostly aged 40-49 at intermediate familial risk of breast cancer. One hundred and three cases of breast cancer were age-matched to one or two controls. Density was measured by semiautomated interactive thresholding. Absolute density, but not percent density, was a significant risk factor for breast cancer in this population after adjusting for area of nondense tissue (OR per 10 cm(2) = 1.07, 95% CI 1.00-1.15, p = 0.04). The effect was stronger in premenopausal women, who made up the majority of the study population. Absolute density remained a significant predictor of breast cancer risk after adjusting for age at menarche, age at first live birth, parity, past or present hormone replacement therapy, and the Tyrer-Cuzick 10-year relative risk estimate of breast cancer. Absolute density can improve breast cancer risk stratification and delineation of high-risk groups alongside the Tyrer-Cuzick 10-year relative risk estimate. © 2014 UICC.

Primary health care utilization prior to suicide: a retrospective case-control study among active-duty military personnel.

PubMed

Hochman, Eldar; Shelef, Leah; Mann, J John; Portugese, Shirly; Krivoy, Amir; Shoval, Gal; Weiser, Mark; Fruchter, Eyal

2014-08-01

About 45% of civilians who died by suicide had contact with a doctor within 1 month of death. Thus, educating primary care physicians (PCP) to detect and mitigate depression is an important suicide-prevention strategy. However, the PCP consulting rate before suicide has not been examined in a military population. We investigated the utilization of primary health care and mental health services by active-duty military personnel suicide cases prior to death in comparison to matched military controls. All suicides (N = 170) were extracted from a cohort of all active-duty Israeli military male personnel between 2002 and 2012. Applying a retrospective, nested case-control design, we compared primary care services utilization by suicide cases with demographic and occupationally matched military controls (N = 500). Whereas 38.3% of suicide cases contacted a PCP within the last month before death, only 27.6% of suicide cases contacted a mental health specialist during their entire service time. The PCP contact rate within 1 month before death or index day did not differ between suicide cases and military controls (38.3% vs. 33.8%, χ²₁ = 1.05, P = .3). More suicide cases contacted a mental health specialist within service time than did military controls (27.6% vs. 13.6%, χ²₁ = 10.85, P = .001). Even though PCP contact rate by military personnel who died by suicide is slightly lower than that reported for civilians who died by suicide prior to their death, it is higher than mental health specialist contact rate and higher than that by age-matched civilians who died by suicide. These results imply that PCPs education is a viable approach to suicide prevention in a military setting. © Copyright 2014 Physicians Postgraduate Press, Inc.

Recurrence of tuberculosis among patients following treatment completion in eight provinces of Vietnam: a nested case-control study.

PubMed

Bestrashniy, Jessica Rutledge Bruce Musselman; Nguyen, Viet Nhung; Nguyen, Thi Loi; Pham, Thi Lieu; Nguyen, Thu Anh; Pham, Duc Cuong; Nghiem, Le Phuong Hoa; Le, Thi Ngoc Anh; Nguyen, Binh Hoa; Nguyen, Kim Cuong; Nguyen, Huy Dung; Buu, Tran Ngoc; Le, Thi Nhung; Nguyen, Viet Hung; Dinh, Ngoc Sy; Britton, Warwick John; Marks, Guy Barrington; Fox, Greg James

2018-06-23

Patients completing treatment for tuberculosis (TB) in high-prevalence settings face a risk of developing recurrent disease. This has important consequences for public health, given its association with drug resistance and a poor prognosis. Previous research has implicated individual factors such as smoking, alcohol use, HIV, poor treatment adherence, and drug resistant disease as risk factors for recurrence. However, little is known about how these factors co-act to produce recurrent disease. Furthermore, perhaps factors related to the index disease means higher burden/low resource settings may be more prone to recurrent disease that could be preventable. We conducted a case-control study nested within a cohort of consecutively enrolled adults who were being treated for smear positive pulmonary TB in 70 randomly selected district clinics in Vietnam. Cases were patients with recurrent TB, identified by follow-up from the parent cohort study. Controls were selected from the cohort by random sampling. Information on demographic, clinical and disease-related characteristics was obtained by interview. information was extracted from clinic registries. Logistic regression, with stepwise selection, was used to develop a fully adjusted model for the odds of recurrence of TB. We recruited 10,964 patients between October 2010 and July 2013. Median follow-up was 988 days. At the end of follow-up, 505 patients (4.7%) with recurrence were identified as cases and 630 other patients were randomly selected as controls. Predictors of recurrence included multidrug-resistant (MDR)-TB (adjusted odds ratio 79.6; 95% CI: 25.1-252.0), self-reported prior TB therapy (aOR=2.5; 95% CI: 1.7-3.5), and incomplete adherence (aOR=1.9; 95% CI 1.1-3.1). Index disease treatment history is a leading determinant of relapse among patients with TB in Vietnam. Further research is required to identify interventions that will reduce the risk of recurrent disease and enhance its early detection within high-risk populations. Copyright © 2018. Published by Elsevier Ltd.

Population dynamics of Hawaiian seabird colonies vulnerable to sea-level rise

USGS Publications Warehouse

Hatfield, Jeff S.; Reynolds, Michelle H.; Seavy, Nathaniel E.; Krause, Crystal M.

2012-01-01

Globally, seabirds are vulnerable to anthropogenic threats both at sea and on land. Seabirds typically nest colonially and show strong fidelity to natal colonies, and such colonies on low-lying islands may be threatened by sea-level rise. We used French Frigate Shoals, the largest atoll in the Hawaiian Archipelago, as a case study to explore the population dynamics of seabird colonies and the potential effects sea-level rise may have on these rookeries. We compiled historic observations, a 30-year time series of seabird population abundance, lidar-derived elevations, and aerial imagery of all the islands of French Frigate Shoals. To estimate the population dynamics of 8 species of breeding seabirds on Tern Island from 1980 to 2009, we used a Gompertz model with a Bayesian approach to infer population growth rates, density dependence, process variation, and observation error. All species increased in abundance, in a pattern that provided evidence of density dependence. Great Frigatebirds (Fregata minor), Masked Boobies (Sula dactylatra), Red-tailed Tropicbirds (Phaethon rubricauda), Spectacled Terns (Onychoprion lunatus), and White Terns (Gygis alba) are likely at carrying capacity. Density dependence may exacerbate the effects of sea-level rise on seabirds because populations near carrying capacity on an island will be more negatively affected than populations with room for growth. We projected 12% of French Frigate Shoals will be inundated if sea level rises 1 m and 28% if sea level rises 2 m. Spectacled Terns and shrub-nesting species are especially vulnerable to sea-level rise, but seawalls and habitat restoration may mitigate the effects of sea-level rise. Losses of seabird nesting habitat may be substantial in the Hawaiian Islands by 2100 if sea levels rise 2 m. Restoration of higher-elevation seabird colonies represent a more enduring conservation solution for Pacific seabirds.

Does increasing daylength control seasonal changes in clutch sizes of Northern Pintails (Anas acuta)?

USGS Publications Warehouse

Krapu, G.L.; Sargeant, G.A.; Perkins, A.E.H.

2002-01-01

We evaluated spatiotemporal variation in clutch sizes of Northern Pintails (pintails; Anas acuta) nesting in California (1985 to 1996), North Dakota (1982 to 1985), Saskatchewan (1982 to 1985) and Alaska (1991 to 1993) to determine whether seasonal declines in clutch size varied in ways that were consistent with a controlling influence of increasing day length. Pintails began nesting in mid-March in California, mid-April in North Dakota and Saskatchewan, and mid-May in Alaska. Observed durations of nesting were 70 ± 2.6 days (SE) in California, 60 ± 6.3 days in North Dakota, 66 ± 1.3 days in Saskatchewan, and 42 ± 0.7 days in Alaska. Annual differences were the principal source of variation in mean clutch sizes (σ̂Y2 = 0.15, SE = 0.049), which varied little among study locations (σ̂A2 = 0.002, SE = 0.013). Predicted rates of seasonal decline in clutch sizes increased with latitude early in the nesting season, but declined as the nesting season progressed, except in California. Rates of decline in clutch sizes thus were not directly related to rates of increase in day length. Predicted declines in numbers of eggs per clutch over the nesting season were similar for all four locations (range, 3.05–3.12) despite wide variation in durations of nesting. Evidence suggests that reduced nutrient availability during nesting contributes to a higher rate of decline in clutch sizes in Alaska than in temperate regions. Pintails that nest early lay large initial clutches, but thereafter clutch sizes decline rapidly and breeding terminates early. This reproductive strategy is adaptive because young that hatch earliest exhibit the highest survival rates; however, the conversion of grassland to cropland on the primary prairie breeding grounds has reduced hatching rates of clutches laid early in the nesting season. Under these conditions, the limited capacity to renest in late spring on their prairie breeding grounds probably has contributed to Pintail population declines.

Nested PCR Assay for Eight Pathogens: A Rapid Tool for Diagnosis of Bacterial Meningitis.

PubMed

Bhagchandani, Sharda P; Kubade, Sushant; Nikhare, Priyanka P; Manke, Sonali; Chandak, Nitin H; Kabra, Dinesh; Baheti, Neeraj N; Agrawal, Vijay S; Sarda, Pankaj; Mahajan, Parikshit; Ganjre, Ashish; Purohit, Hemant J; Singh, Lokendra; Taori, Girdhar M; Daginawala, Hatim F; Kashyap, Rajpal S

2016-02-01

Bacterial meningitis is a dreadful infectious disease with a high mortality and morbidity if remained undiagnosed. Traditional diagnostic methods for bacterial meningitis pose a challenge in accurate identification of pathogen, making prognosis difficult. The present study is therefore aimed to design and evaluate a specific and sensitive nested 16S rDNA genus-based polymerase chain reaction (PCR) assay using clinical cerebrospinal fluid (CSF) for rapid diagnosis of eight pathogens causing the disease. The present work was dedicated to development of an in-house genus specific 16S rDNA nested PCR covering pathogens of eight genera responsible for causing bacterial meningitis using newly designed as well as literature based primers for respective genus. A total 150 suspected meningitis CSF obtained from the patients admitted to Central India Institute of Medical Sciences (CIIMS), India during the period from August 2011 to May 2014, were used to evaluate clinical sensitivity and clinical specificity of optimized PCR assays. The analytical sensitivity and specificity of our newly designed genus-specific 16S rDNA PCR were found to be ≥92%. With such a high sensitivity and specificity, our in-house nested PCR was able to give 100% sensitivity in clinically confirmed positive cases and 100% specificity in clinically confirmed negative cases indicating its applicability in clinical diagnosis. Our in-house nested PCR system therefore can diagnose the accurate pathogen causing bacterial meningitis and therefore be useful in selecting a specific treatment line to minimize morbidity. Results are obtained within 24 h and high sensitivity makes this nested PCR assay a rapid and accurate diagnostic tool compared to traditional culture-based methods.

Distribution and abundance of anadromous Sea Lamprey Spawners in a fragmented stream: Current status and potential range expansion following barrier removal

USGS Publications Warehouse

Zydlewski, Joseph D.; Gardner, Cory; Coghlan, Stephen M.

2012-01-01

Dams fragment watersheds and prevent anadromous fishes from reaching historic spawning habitat. Sedgeunkedunk Stream, a small tributary to the Penobscot River (Maine), has been the focus of efforts to reestablish marine-freshwater connectivity and restore anadromous fishes via the removal of two barriers to fish migration. Currently, Petromyzon marinus (Sea Lamprey) is the only anadromous fish known to spawn successfully in the stream downstream of the lowermost dam. Here, we describe the distribution and abundance of a spawning population of Sea Lamprey in Sedgeunkedunk Stream, prior to and in anticipation of habitat increase after the completion of one barrier removal. In 2008, we estimated the abundance of Sea Lamprey and its nests using daily stream surveys and an open-population mark-recapture model. We captured 47 Sea Lamprey and implanted each with a PIT tag so that we could track movements and nest associations of individual fish. The spawning migration began on 18 June, and the last living individual was observed on 27 June. We located 31 nests, distributed from head-of-tide to the lowermost dam; no spawners or nests were observed in the tidally influenced zone or upstream of this dam. Mean longevity in the stream and the number of nests attended were correlated with arrival date; early migrants were alive longer and attended more nests than later migrants. Males were more likely to be observed away from a nest, or attending three or more nests, than were females, which attended usually one or two nests. We observed a negative association between nest abundance and substrate cover by fine sediment. Based on their observed movements in the system, and the extent of their habitat use, we anticipate that spawning Sea Lamprey will recolonize formerly inaccessible habitat after dam removals.

Housing and health in Germany.

PubMed

Pollack, C E; von dem Knesebeck, O; Siegrist, J

2004-03-01

To examine the association between housing tenure and self rated health, controlling for socioeconomic measures and testing the mediating effects of physical features of the home, pollution in the local environment, and relationships with neighbours. Cross sectional panel study with people nested within households. Analyses were performed using multilevel methods. Population based sample in Germany. People aged 16 or older were interviewed in the 1999 wave of the socio-economic panel study (n = 14 055) and nested within households (n = 7381). 44.0% of the population lived in homes that they owned. In bivariate analyses, women, people who live in apartment buildings, reside near cities, live in crowded homes, have homes in need of renovation, report higher pollution, and have distant contact with neighbours are more likely to live in rented homes. In multilevel analyses, renting a home was found to be associated with poor self rated health (OR 1.48, 95% CI 1.31 to 1.68). This relation persisted after controlling for education and income and was partially mediated by the need for household renovation, the perception of air and noise pollution in the local area, and distant relationship with neighbours, all of which were significantly associated with self rated health. This study provides evidence that home ownership is significantly associated with self rated health in Germany, and this relation may be, in part, mediated by physical and social features of home and neighbourhood.

Exposure assessment for a nested case-control study of lung cancer among European asphalt workers.

PubMed

Agostini, Michela; Ferro, Gilles; Olsson, Ann; Burstyn, Igor; De Vocht, Frank; Hansen, Johnni; Lassen, Christina Funch; Johansen, Christoffer; Kjaerheim, Kristina; Langard, Sverre; Stucker, Isabelle; Ahrens, Wolfgang; Behrens, Thomas; Lindbohm, Marja-Liisa; Heikkilä, Pirjo; Heederik, Dick; Portengen, Lützen; Shaham, Judith; Boffetta, Paolo; Kromhout, Hans

2010-10-01

Development of a method for retrospective assessment of exposure to bitumen fume, bitumen condensate, organic vapour, polycyclic aromatic hydrocarbons, and co-exposures to known or suspected lung carcinogens for a nested case-control study of lung cancer mortality among European asphalt workers. Company questionnaires and structured questionnaires used in interviews and industry-specific job-exposure matrices (JEMs) were elaborated and applied. Three sources of information were eventually used for exposure assessment and assignment: (i) data obtained in cohort phase, (ii) data from living subjects, next-of-kin, and fellow-workers questionnaires, and (iii) JEMs for bitumen exposure by inhalation and via skin and co-exposures to known or suspected lung carcinogens within and outside cohort companies. Inhalation and dermal exposure estimates for bitumen were adjusted for time trends, time spent in a job, and other determinants of exposure (e.g. oil gravel paving). Clothing patterns, personal protective devices, and personal hygiene were taken into consideration while estimating dermal exposure. Occupational exposures could be assessed for 433 cases and 1253 controls for relevant time periods. Only 43% of work histories were spent inside original asphalt and construction companies. A total of 95.8% of job periods in cohort companies could be coded at a more detailed level. Imputation of work time and 'hygienic behaviour' multipliers was needed for <10% of work history years. Overall, downward trends in exposure were present and differences existed between countries and companies. As expected, correlations were strongest (r > 0.7) among bitumen-related agents, while correlations between coal tar, bitumen-related agents, and established lung carcinogens were weaker (r < 0.4). A systematic and detailed approach was developed to estimate inhalation and dermal exposure for a nested case-control study among asphalt workers.

Association of empty nest with depressive symptom in a Chinese elderly population: A cross-sectional study.

PubMed

Zhai, Yujia; Yi, Huaiming; Shen, Wei; Xiao, Yuanyuan; Fan, Haixiao; He, Fan; Li, Fudong; Wang, Xinyi; Shang, Xiaopeng; Lin, Junfen

2015-11-15

Empty nest has been becoming the main family pattern among old people, and influencing the traditional family providing for the aged in China. This study aimed to investigate the association of empty nest with depressive symptom in a Chinese elderly population. Our study was based on the baseline investigation of Zhejiang Major Public Health Surveillance which was conducted in 2014. The final analyzed sample consisted of 9215 participants aged no less than 60 years. Subjects completed a questionnaire including demographic characteristics, living arrangements, behavioral risk factors, health status, subjective assessments, and Patient Health Questionnaire-9 scale. More than half of the participants were empty nest elders (57.4%). The overall prevalence of depressive symptom was 10.3%, while it was higher in empty nest group than in non-empty nest group (11.6% vs. 8.6%, P<0.001). A positive association was found between empty nest and depressive symptom, the OR (95%CI) was 1.223(1.045, 1.431). After stratified by gender/age/education level/employment status, this association was just prominent in participants of male, 70 years old and above, primary school education, and retirees. No matter living with spouse or living alone, empty nesters were more likely to have depressive symptoms than non-empty nesters. Cross-sectional study could not make a causation conclusion. The social supports of participants were not been investigated in detail. Empty nest elders, especially those who are male, 70 years old and above, primary school education, and retired, are more vulnerable to depressive symptom. Copyright © 2015 Elsevier B.V. All rights reserved.

Like mother, like daughter: inheritance of nest-site location in snakes.

PubMed

Brown, Gregory P; Shine, Richard

2007-04-22

A trait can be passed from parents to offspring even if it has no genetic basis. For example, if daughters return to reproduce at the same sites where they were hatched themselves, nest-site location is consistent within matrilineages. Most cases of natal homing (nest-site philopatry) across generations have been inferred from molecular evidence rather than directly demonstrated, and involve species with low dispersal abilities. However, some animals disperse long distances but then return to their own place of birth to reproduce, based on cues imprinted early in their own development. Our field studies on tropical natricine snakes (Tropidonophis mairii, Colubridae) show that when they are ready to nest, females return to the sites where their mothers were captured pre-nesting, and where they themselves were released as hatchlings.

Impact of jaguar Panthera onca (Carnivora: Felidae) predation on marine turtle populations in Tortuguero, Caribbean coast of Costa Rica.

PubMed

Arroyo-Arce, Stephanny; Salom-Pérez, Roberto

2015-09-01

Little is known about the effects of jaguars on the population of marine turtles nesting in Tortuguero National Park, Costa Rica. This study assessed jaguar predation impact on three species of marine turtles (Chelonia mydas, Dermochelys coriacea and Eretmochelys imbricata) that nest in Tortuguero beach. Jaguar predation data was obtained by using two methodologies, literature review (historical records prior the year 2005) and weekly surveys along the 29 km stretch of beach during the period 2005-2013. Our results indicated that jaguar predation has increased from one marine turtle in 1981 to 198 in 2013. Jaguars consumed annually an average of 120 (SD = 45) and 2 (SD = 3) green turtles and leatherbacks in Tortuguero beach, respectively. Based on our results we concluded that jaguars do not represent a threat to the population of green turtles that nest in Tortuguero beach, and it is not the main cause for population decline for leatherbacks and hawksbills. Future research should focus on continuing to monitor this predator-prey relationship as well as the factors that influence it so the proper management decisions can be taken.

Field-based random sampling without a sampling frame: control selection for a case-control study in rural Africa.

PubMed

Crampin, A C; Mwinuka, V; Malema, S S; Glynn, J R; Fine, P E

2001-01-01

Selection bias, particularly of controls, is common in case-control studies and may materially affect the results. Methods of control selection should be tailored both for the risk factors and disease under investigation and for the population being studied. We present here a control selection method devised for a case-control study of tuberculosis in rural Africa (Karonga, northern Malawi) that selects an age/sex frequency-matched random sample of the population, with a geographical distribution in proportion to the population density. We also present an audit of the selection process, and discuss the potential of this method in other settings.

Nest-site selection in the acorn woodpecker

USGS Publications Warehouse

Hooge, P.N.; Stanback, M.T.; Koenig, Walter D.

1999-01-01

Acorn Woodpeckers (Melanerpes formicivorus) at Hastings Reservation in central California prefer to nest in dead limbs in large, dead valley oaks (Quercus lobata) and California sycamores (Platanus racemosa) that are also frequently used as acorn storage trees. Based on 232 nest cavities used over an 18-year period, we tested whether preferred or modal nest-site characters were associated with increased reproductive success (the "nest-site quality" hypothesis). We also examined whether more successful nests were likely to experience more favorable microclimatic conditions or to be less accessible to terrestrial predators. We found only equivocal support for the nest-site quality hypothesis: only 1 of 5 preferred characters and 2 of 10 characters exhibiting a clear modality were correlated with higher reproductive success. All three characteristics of nests known or likely to be associated with a more favorable microclimate, and two of five characteristics likely to render nests less accessible to predators, were correlated with higher reproductive success. These results suggest that nest cavities in this population are built in part to take advantage of favorable microclimatic conditions and, to a lesser extent, to reduce access to predators. However, despite benefits of particular nest characteristics, birds frequently nested in apparently suboptimal cavities. We also found a significant relationship between mean group size and the history of occupancy of particular territories and the probability of nest cavities being built in microclimatically favorable live limbs, suggesting that larger groups residing on more stable territories were better able to construct nests with optimal characteristics. This indicates that there may be demographic, as well as ecological, constraints on nest-site selection in this primary cavity nester.

Species associations and habitat influence the range-wide distribution of breeding Canada Geese (Branta canadensis interior) on Western Hudson Bay

USGS Publications Warehouse

Reiter, Matthew E.; Andersen, David E.; Raedeke, Andrew H.; Humburg, Dale D.

2017-01-01

Inter- and intra-specific interactions are potentially important factors influencing the distribution of populations. Aerial survey data, collected during range-wide breeding population surveys for Eastern Prairie Population (EPP) Canada Geese (Branta canadensis interior), 1987–2008, were evaluated to assess factors influencing their nesting distribution. Specifically, associations between nesting Lesser Snow Geese (Chen caerulescens caerulescens) and EPP Canada Geese were quantified; and changes in the spatial distribution of EPP Canada Geese were identified. Mixed-effects Poisson regression models of EPP Canada Goose nest counts were evaluated within a cross-validation framework. The total count of EPP Canada Goose nests varied moderately among years between 1987 and 2008 with no long-term trend; however, the total count of nesting Lesser Snow Geese generally increased. Three models containing factors related to previous EPP Canada Goose nest density (representing recruitment), distance to Hudson Bay (representing brood-habitat), nesting habitat type, and Lesser Snow Goose nest density (inter-specific associations) were the most accurate, improving prediction accuracy by 45% when compared to intercept-only models. EPP Canada Goose nest density varied by habitat type, was negatively associated with distance to coastal brood-rearing areas, and suggested density-dependent intra-specific effects on recruitment. However, a non-linear relationship between Lesser Snow and EPP Canada Goose nest density suggests that as nesting Lesser Snow Geese increase, EPP Canada Geese locally decline and subsequently the spatial distribution of EPP Canada Geese on western Hudson Bay has changed.

The Rocky Mountain population of the western Canada goose: its distribution, habitats, and management

USGS Publications Warehouse

Krohn, William B.; Bizeau, Elwood G.

1980-01-01

The western Canada goose (Branta canadensis moffitti) was divided into a Rocky Mountain population (RMP) and a Pacific population (PP) on the basis of band recovery patterns examined in this study and recovery data from other investigators. Habitat information obtained from nine cooperating wildlife agencies within the RMP's range provided a base line for evaluating future changes in nesting, molting, and wintering areas. The habitat inventory indicated that none of the seasonal habitats were currently limiting the size of the RMP. The RMP's range is divided into 15 reference areas and these are briefly described. Past studies of Canada geese in the Intermountain Region are reviewed. Topics covered in the discussion of breeding biology are nesting chronology, spring population composition, breeding age, clutch size, nesting success. artificial nesting structures, and gosling survival. Much of the mortality of Canada geese occurs before the birds are fledged. Man-made nesting structures reduce losses during incubation. but research is needed on the relations between brooding sites and gosling survival. Some western Canada geese, mainly prebreeders and unsuccessful nesters, make molt migrations to and from molting areas during and after the brood-rearing season. More than half of these molt-migrants are yearlings too young to nest; there are indications that even some successful nesters leave nesting areas to molt before the fledging of their offspring. Geese 2 years old or older may serve as guides to traditional molting areas for the first-time migrants (i.e., yearlings). Lack of disturbance appears to influence selection of specific molting areas within the nesting range of moffitti, whereas movements of molters out of the Intermountain Region may be related to the evolution of this subspecies. Apparently. molters of both the PP and RMP that leave the Region go to the Northwest Territories of Canada. Although the taxonomic status of moffitti as related to the giant Canada goose (B. c. maxima) is unclear. these two subspecies are closely related. as evidenced by similar molt migrations to subarctic Canada. similar blood serum proteins. and only dinal differences in body size ,!!nd color. Mean annual survival rates for birds banded on nesting areas averaged 53 ? 2% (X ? SE) for immatures and 64 ? 1 % for adults. Mean annual survival rates of adults captured on molting areas averaged 70 ? 1 %. Sport hunting accounts for more than 86% of the mortality of fledged Rocky Mountain geese. and hunting may limit the population's growth. Because the number of waterfowl hunters in the Rocky Mountain West is increasing, the continued expansion or future maintenance of the RMP may require more restrictive hunting regulations. Other management recommendations include the refinement and standardization of spring and winter aerial surveys, and more accurate age and sex determinations when geese are banded and color-marked.

Aetiology of childhood pneumonia in a well vaccinated South African birth cohort: a nested case-control study

PubMed Central

Zar, HJ; Barnett, W; Stadler, A; Gardner-Lubbe, S; Myer, L; Nicol, MP

2016-01-01

Background Pneumonia is a leading cause of mortality and morbidity in children globally. The aetiology of pneumonia following introduction of 13-valent pneumococcal conjugate vaccine (PCV13) has not been well studied in low- and middle-income countries; furthermore most data is from cross-sectional studies of hospitalized cases. We aimed to longitudinally investigate the incidence and aetiology of childhood pneumonia in a South African birth cohort. Methods Children in the Drakenstein Child Health Study were followed from birth from May 2012 to Dec 2014. Immunizations included acellular pertussis vaccine and PCV13. A nested subgroup had nasopharyngeal swabs (NPs) collected 2-weekly through infancy. Pneumonia episodes were identified and blood, NPs and induced sputum (IS) specimens obtained. Multiplex real-time PCR for pathogens was done on NPs and IS of pneumonia cases and on NPs of age- and site-matched controls. Associations between organisms and pneumonia used conditional logistic regression; results are presented as odds ratios (OR) with 95% confidence intervals (CI). Findings Overall 314 pneumonia cases occurred (incidence 0·27 episodes per child year (e/cy); median age 5 months) in 967 children during 1145 child-years of follow-up. Severe pneumonia occurred in 60 (21%) of cases (incidence 0·07 e/cy) with a case fatality ratio of 1%. A median of 5 organisms were detected in cases and controls with a median of 6 on IS (p=0·48 compared to NPs). Bordetella pertussis [OR 11·08; 95% CI 1·33-92·54; 7/696 positive], Respiratory Syncytial Virus [OR 8·05; 95% CI 4·21-15·38; 83/696 positive] or influenza virus [OR 4·13; 95% CI 2·06-8·26; 43/696 positive] were most strongly associated with pneumonia; bocavirus, parainfluenza virus, adenovirus, cytomegalovirus and Haemophilus influenzae. were also associated with pneumonia. In cases, testing of IS in addition to NPs provided incremental yield for B. pertussis and several viruses. Interpretation Pneumonia remains common in this highly vaccinated population. RSV was the most frequently detected pathogen associated with pneumonia; influenza virus and B. pertussis were also strongly associated with pneumonia. Testing of IS increases the yield for several organisms. New vaccines and strategies are needed to address the burden of childhood pneumonia. PMID:27117547

Identification of VaD and AD prodromes: the Cache County Study.

PubMed

Hayden, K M; Warren, L H; Pieper, C F; Østbye, T; Tschanz, J T; Norton, M C; Breitner, J C S; Welsh-Bohmer, K A

2005-07-01

It is unclear whether vascular dementia (VaD) has a cognitive prodrome, akin to the mild cognitive impairment (MCI) prodrome to Alzheimer's dementia (AD). To evaluate whether VaD has a cognitive prodrome, and if it can be differentiated from prodromal AD, we examined neuropsychological test performance of participants in a nested case-control study within a population-based cohort aged 65 or older. Participants (n = 485) were identified from the Cache County Study, a large population-based study of aging and dementia. After an average of 3 years of follow-up, a total of 62 incident dementia cases were identified (14 VaD, 48 AD). We identified a number of neuropsychological tests (executive and memory) that discriminated between diagnosed VaD and AD cases. Multivariate analyses sought to differentiate between these same groups 3 years before clinical diagnosis. The Consortium to Establish a Registry for Alzheimer's Disease Word List Recognition Test correct recognition of foils (mean difference, 1.25; 95% confidence interval [CI], 0.42 to 2.07; p < 0.01), Logical Memory I (mean difference, 7.16; 95% CI, 0.78 to 13.55, p < 0.05), Logical Memory II delayed recall (mean difference, 8.67; 95% CI, 1.59 to 15.74, p < 0.05), and percent savings (mean difference, 51.07; 95% CI, 32.58 to 69.56, p < 0.0001) differentiated VaD from AD cases after adjustment for age, sex, education, and dementia severity. Three years before dementia diagnosis, word list recognition ("no" responses mean difference, 1.40; 95% CI, 0.64 to 2.17; p < 0.001, and "yes" responses mean difference, -1.14; 95% CI, -2.14 to -0.13; p < 0.03) discriminated between prodromal VaD and AD. These results suggest that VaD has a prodromal syndrome, the cognitive features of which are distinguishable from the cognitive prodrome of AD.

Association of Bacterial Vaginosis With Chlamydia and Gonorrhea Among Women in the U.S. Army.

PubMed

Bautista, Christian T; Wurapa, Eyako K; Sateren, Warren B; Morris, Sara M; Hollingsworth, Bruce P; Sanchez, Jose L

2017-05-01

Bacterial vaginosis (BV) is a common vaginal condition in women of reproductive age, which has been associated with Chlamydia trachomatis and Neisseria gonorrhoeae among commercial sex workers and women attending sexually transmitted infection clinics. Pathogen-specific associations between BV and other sexually transmitted infections among U.S. military women have not been investigated. A population-based, nested case-control study was conducted of all incident chlamydia and gonorrhea cases reported to the Defense Medical Surveillance System during 2006-2012. Using a density sampling approach, for each chlamydia or gonorrhea case, 10 age-matched (±1 year) controls were randomly selected from those women who were never diagnosed with these infections. Incidence rate ratios were estimated using conditional logistic regression. Statistical analysis was carried out in December 2015. A total of 37,149 chlamydia cases and 4,987 gonorrhea cases were identified during the study period. Antecedent BV was associated with an increased risk of subsequent chlamydia (adjusted incidence rate ratio=1.51; 95% CI=1.47, 1.55) and gonorrhea (adjusted incidence rate ratio=2.42; 95% CI=2.27, 2.57) infections. For every one additional episode of BV, the risk of acquiring chlamydia and gonorrhea infections increased by 13% and 26%, respectively. A monotonic dose-response relationship was also noted between antecedent BV and subsequent chlamydia and gonorrhea infection. In addition, an effect modification on the additive scale was found between BV and African-American race for gonorrhea, but not for chlamydia. Among U.S. Army women, antecedent BV is associated with an increased risk of subsequent chlamydia and gonorrhea infection. Copyright © 2016 American Journal of Preventive Medicine. All rights reserved.

Comparison of Microscopy, Nested-PCR, and Real-Time-PCR Assays Using High-Throughput Screening of Pooled Samples for Diagnosis of Malaria in Asymptomatic Carriers from Areas of Endemicity in Myanmar

PubMed Central

Wang, Bo; Han, Soe-Soe; Cho, Cho; Han, Jin-Hee; Cheng, Yang; Lee, Seong-Kyun; Galappaththy, Gawrie N. L; Thimasarn, Krongthong; Soe, Myat Thu; Oo, Htet Wai; Kyaw, Myat Phone

2014-01-01

Asymptomatic infection is an important obstacle for controlling disease in countries where malaria is endemic. Because asymptomatic carriers do not seek treatment for their infections, they can have high levels of gametocytes and constitute a reservoir available for new infection. We employed a sample pooling/PCR-based molecular detection strategy for screening malaria infection in residents from areas of Myanmar where malaria is endemic. Blood samples (n = 1,552) were collected from residents in three areas of malaria endemicity (Kayin State, Bago, and Tanintharyi regions) of Myanmar. Two nested PCR and real-time PCR assays showed that asymptomatic infection was detected in about 1.0% to 9.4% of residents from the surveyed areas. The sensitivities of the two nested PCR and real-time PCR techniques were higher than that of microscopy examination (sensitivity, 100% versus 26.4%; kappa values, 0.2 to 0.5). Among the three regions, parasite-positive samples were highly detected in subjects from the Bago and Tanintharyi regions. Active surveillance of residents from regions of intense malaria transmission would reduce the risk of morbidity and mitigate transmission to the population in these areas of endemicity. Our data demonstrate that PCR-based molecular techniques are more efficient than microscopy for nationwide surveillance of malaria in countries where malaria is endemic. PMID:24648557

The Robustness of Designs for Trials with Nested Data against Incorrect Initial Intracluster Correlation Coefficient Estimates

ERIC Educational Resources Information Center

Korendijk, Elly J. H.; Moerbeek, Mirjam; Maas, Cora J. M.

2010-01-01

In the case of trials with nested data, the optimal allocation of units depends on the budget, the costs, and the intracluster correlation coefficient. In general, the intracluster correlation coefficient is unknown in advance and an initial guess has to be made based on published values or subject matter knowledge. This initial estimate is likely…

Lifestyle, environmental pollution and lung cancer in cities of Liaoning in northeastern China.

PubMed

Xu, Z Y; Brown, L; Pan, G W; Li, G; Feng, Y P; Guan, D X; Liu, T F; Liu, L M; Chao, R M; Sheng, J H; Gao, G C

1996-03-01

Several studies were conducted in cities of Liaoning Province, one of the areas of China with heavy concentrations of industry, to investigate the effects of life-style factors and environmental pollutants on lung cancer causation. A case-control study involving 1249 lung cancer patients and 1345 population-based controls was conducted in 1985-1988 in Shenyang, the capital of Liaoning. Cigarette smoking was found to be the principal cause of lung cancer in this population, accounting for 55% of the disease in males and 37% in females. There was also a significant increase in lung cancer risk associated with an overall index of indoor air pollution due to coal-burning emission. The population attributable risk (PAR) for indoor air pollution was 13% for males and 17% for females. Risks were significantly increased for workers in the non-ferrous smelter (odds ratio (OR) = 2.6, 95% CI, 1.3-5.1), chemical and drug manufacturing (OR = 3.0, 95% CI, 1.0-8.0), and the glass and pottery industry (OR = 1.6, 95% CI, 1.0-2.5). Studies in the Anshan Iron-Steel Complex showed a significant excess of lung cancer for workers exposed to a variety of dusts. A standardized proportional mortality ratio (SPMR) study of 8887 deaths during 1980-1989 among male workers of the complex indicated a 37% excess risk of lung cancer compared to residents of the city. A nested case-control study was then conducted in that complex. A total of 610 cases of lung cancer diagnosed during 1987-1993 and 959 randomly selected controls from 196 993 active and retired employees of the complex were interviewed. Historical monitoring records for dust and benzo(a)pyrene (B(a)P) were collected from 1956-1992 to calculate cumulative exposure for each person. Results suggested that risks were increased for all occupations in which there was exposure to dusts, with the highest risks seen among coke oven workers (OR = 3.5, 95% CI, 2.0-6.4) and fire-resistant brick makers (OR = 2.9, 95% CI, 1.9-4.4). Significant dose-response patterns between cumulative total dust, cumulative total B(a)P and lung cancer risk were observed. The findings suggest that smoking and environmental pollution combine to account for elevated rates of lung cancer in cities of northeastern China.

Interaction between air pollution exposure and genes in relation to levels of inflammatory markers and risk of myocardial infarction

PubMed Central

Panasevich, Sviatlana; Leander, Karin; Ljungman, Petter; Bellander, Tom; de Faire, Ulf; Pershagen, Göran; Nyberg, Fredrik

2013-01-01

Objectives Air pollution exposure induces cardiovascular effects, possibly via systemic inflammation and coagulation misbalance. Genetic variation may determine individual susceptibility. Our aim was to investigate effect modification by inflammation (Interleukin6 (IL6), tumour necrosis factor-α (TNF-α)) and coagulation (fibrinogen Bβ, plasminogen activator inhibitor-1 (PAI-1)) gene variants on the effect of long-term or short-term air pollution exposure on both blood marker levels and non-fatal myocardial infarction (MI) risk. Design Population-based case–control study with a nested case-crossover study. Gene-environment interactions for short-term and long-term air pollution on blood marker levels were studied in population controls, for long-term exposure on MI risk using case–control design, and for short-term exposure on MI onset using case-crossover design. Setting The Stockholm Heart Epidemiology Programme (SHEEP) conducted in 1992–1994 in Stockholm, Sweden. Spatial modelling was used to assess long-term (up to 30 years retrospectively) air pollution exposure to traffic-NO2 and heating-SO2 emissions at home addresses. Urban background NO2, SO2, PM10 and O3 measurements were used to estimate short-term (up to 5 days) air pollution exposure. Participants 1192 MI cases and 1506 population controls aged 45–70 years. Outcomes The levels of blood markers of inflammation (IL-6, TNF-α) and coagulation (fibrinogen, PAI-1) and MI risk. Results We observed gene–environment interaction for several IL6 and TNF SNPs in relation to inflammation blood marker levels. One-year traffic-NO2 exposure was associated with higher IL-6 levels with each additional IL6-174C allele, and 1-year heating-SO2 exposure with higher levels of TNF-α in TNF-308AA homozygotes versus −308G carriers. Short-term air pollution exposure also interacted with IL6 and TNF in relation to marker levels. The risk of MI followed the effect on blood markers in each genotype group. Conclusions Genetic variants in IL6 and TNF may modify effects of long-term and short-term air pollution exposure on inflammatory marker levels and MI risk. PMID:24056475

City housing atmospheric pollutant impact on emergency visit for asthma: A classification and regression tree approach.

PubMed

Mazenq, Julie; Dubus, Jean-Christophe; Gaudart, Jean; Charpin, Denis; Viudes, Gilles; Noel, Guilhem

2017-11-01

Particulate matter, nitrogen dioxide (NO 2 ) and ozone are recognized as the three pollutants that most significantly affect human health. Asthma is a multifactorial disease. However, the place of residence has rarely been investigated. We compared the impact of air pollution, measured near patients' homes, on emergency department (ED) visits for asthma or trauma (controls) within the Provence-Alpes-Côte-d'Azur region. Variables were selected using classification and regression trees on asthmatic and control population, 3-99 years, visiting ED from January 1 to December 31, 2013. Then in a nested case control study, randomization was based on the day of ED visit and on defined age groups. Pollution, meteorological, pollens and viral data measured that day were linked to the patient's ZIP code. A total of 794,884 visits were reported including 6250 for asthma and 278,192 for trauma. Factors associated with an excess risk of emergency visit for asthma included short-term exposure to NO 2 , female gender, high viral load and a combination of low temperature and high humidity. Short-term exposures to high NO 2 concentrations, as assessed close to the homes of the patients, were significantly associated with asthma-related ED visits in children and adults. Copyright © 2017 Elsevier Ltd. All rights reserved.

High-tech or field techs: Radio-telemetry is a cost-effective method for reducing bias in songbird nest searching

USGS Publications Warehouse

Peterson, Sean M.; Streby, Henry M.; Lehman, Justin A.; Kramer, Gunnar R.; Fish, Alexander C.; Andersen, David E.

2015-01-01

We compared the efficacy of standard nest-searching methods with finding nests via radio-tagged birds to assess how search technique influenced our determination of nest-site characteristics and nest success for Golden-winged Warblers (Vermivora chrysoptera). We also evaluated the cost-effectiveness of using radio-tagged birds to find nests. Using standard nest-searching techniques for 3 populations, we found 111 nests in locations with habitat characteristics similar to those described in previous studies: edges between forest and relatively open areas of early successional vegetation or shrubby wetlands, with 43% within 5 m of forest edge. The 83 nests found using telemetry were about half as likely (23%) to be within 5 m of forest edge. We spent little time searching >25 m into forest because published reports state that Golden-winged Warblers do not nest there. However, 14 nests found using telemetry (18%) were >25 m into forest. We modeled nest success using nest-searching method, nest age, and distance to forest edge as explanatory variables. Nest-searching method explained nest success better than nest age alone; we estimated that nests found using telemetry were 10% more likely to fledge young than nests found using standard nest-searching methods. Although radio-telemetry was more expensive than standard nest searching, the cost-effectiveness of both methods differed depending on searcher experience, amount of equipment owned, and bird population density. Our results demonstrate that telemetry can be an effective method for reducing bias in Golden-winged Warbler nest samples, can be cost competitive with standard nest-searching methods in some situations, and is likely to be a useful approach for finding nests of other forest-nesting songbirds.

Genetic susceptibility loci for subtypes of breast cancer in an African American population

PubMed Central

Palmer, Julie R.; Ruiz-Narvaez, Edward A.; Rotimi, Charles N.; Cupples, L. Adrienne; Cozier, Yvette C.; Adams-Campbell, Lucile L.; Rosenberg, Lynn

2012-01-01

Background Most genome-wide association scans (GWAS) have been carried out in European ancestry populations; no risk variants for breast cancer have been identified solely from African ancestry GWAS data. Few GWAS hits have replicated in African ancestry populations. Methods In a nested case-control study of breast cancer in the Black Women’s Health Study (1,199 cases/1,948 controls), we evaluated index SNPs in 21 loci from GWAS of European or Asian ancestry populations, overall, in subtypes defined by estrogen (ER) and progesterone (PR) receptor status (ER+/PR+, n=336; ER−/PR−, n=229), and in triple-negative breast cancer (TNBC, N=81). To evaluate the contribution of genetic factors to population differences in breast cancer subtype, we also examined global percent African ancestry. Results Index SNPs in five loci were replicated, including three associated with ER−/PR− breast cancer (TERT rs10069690 in 5p15.33, rs704010 in 10q22.3, and rs8170 in 19p13.11): per allele odds ratios were 1.29 (95% confidence interval (CI) 1.04–1.59), p=0.02, 1.52 (95% CI 1.12–2.08), p=0.01, and 1.30 (95% CI 1.01–1.68), p=0.04, respectively. Stronger associations were observed for TNBC. Furthermore, cases in the highest quintile of percent African ancestry were three times more likely to have TNBC than ER+/PR+ cancer. Conclusions These findings provide the first confirmation of the TNBC SNP rs8170 in an African ancestry population, and independent confirmation of the TERT ER− SNP. Further, the risk of developing ER− breast cancer, particularly TNBC, increased with increasing proportion of global African ancestry. Impact The findings demonstrate the importance of genetic factors in the disproportionately high occurrence of TNBC in African American women. PMID:23136140

Burrowing owl nesting productivity: A comparison between artificial and natural burrows on and off golf courses

USGS Publications Warehouse

Smith, M.D.; Conway, C.J.; Ellis, L.A.

2005-01-01

Burrowing owl (Athene cunicularia) populations are declining in many portions of their range, and lack of suitable nesting burrows is thought to be one reason for observed declines. Burrowing owls are attracted to golf courses because the birds generally nest and forage in short-grass, open areas, yet golf courses seldom have suitable nesting burrows. We examined the efficacy of installing artificial nesting burrows on golf courses as a way to help restore local burrowing owl populations. From 2001-2004 we monitored over 175 natural burrows off golf courses, 14 natural burrows on golf courses, 86 artificial burrows off golf courses, and 130 artificial burrows on golf courses. Owls located and used 8 of the 130 artificial burrows installed on golf courses (4 were used as nests). Owls selected burrows that were closer to existing natural burrows, farther from maintained areas (areas receiving turf maintenance by golf course staff), and farther from sprinkler heads. All 4 of the artificial burrows used as nests successfully fledged young, and annual site fidelity for owls nesting on golf courses was higher than for owls nesting off golf courses. However, annual fecundity of owls nesting on golf courses was lower than that of owls nesting off golf courses. If golf courses have sufficiently large nonmaintained areas and there are nesting owls nearby, course managers potentially can help in restoring local burrowing owl populations by installing artificial nesting burrows on the periphery of the course. However, the low fecundity on golf courses reported here should be more thoroughly examined before artificial burrows are used to attract owls to golf courses.

Insulin use increases risk of asthma but metformin use reduces the risk in patients with diabetes in a Taiwanese population cohort.

PubMed

Chen, Chiung-Zuei; Hsu, Chih-Hui; Li, Chung-Yi; Hsiue, Tzuen-Ren

2017-12-01

Recent reports have suggested that insulin promotes airway smooth muscle contraction and enhances airway hyperresponsiveness, which are cardinal features of asthma. In contrast, metformin can reduce both airway inflammatory and remodeling properties. However, these results are all from in vitro and animal studies. This study investigated whether diabetes and various antidiabetic agents associate with the risk of asthma. We used a retrospective population-based cohort study using Taiwan's National Health Insurance claim database from 2000 to 2010 and a Cox proportional hazards regression model to compare the incidence of asthma between patients with diabetes (n = 19,428) and a matched non-diabetic group (n = 38,856). We also used a case-control study nested from the above cohort including 1,982 incident cases of asthma and 1,982 age- and sex-matched controls. A time density sampling technique was used to assess the effects of various antidiabetic agents on the risk of asthma. The incidence of asthma was significantly higher in the diabetic cohort than that in the non-diabetic cohort after adjustment for age, sex, and obesity, with a hazard ratio of 1.30 (95% confidence interval [CI]: 1.24-1.38). Insulin was found to increase the risk of asthma among diabetic patients (odds ratio [OR] 2.23; 95% CI: 1.52-3.58). In contrast, the use of metformin correlated with a decreased risk of asthma (OR 0.75; 95% CI: 0.60-0.95). Individuals with diabetes are at an increased risk of asthma. Insulin may further increase the risk of asthma, but the risk could possibly be reduced by using metformin.

Cholinergic autonomic dysfunction in veterans with Gulf War illness: confirmation in a population-based sample.

PubMed

Haley, Robert W; Charuvastra, Elizabeth; Shell, William E; Buhner, David M; Marshall, W Wesley; Biggs, Melanie M; Hopkins, Steve C; Wolfe, Gil I; Vernino, Steven

2013-02-01

The authors of prior small studies raised the hypothesis that symptoms in veterans of the 1991 Gulf War, such as chronic diarrhea, dizziness, fatigue, and sexual dysfunction, are due to cholinergic autonomic dysfunction. To perform a confirmatory test of this prestated hypothesis in a larger, representative sample of Gulf War veterans. Nested case-control study. Clinical and Translational Research Center, University of Texas Southwestern Medical Center, Dallas. Representative samples of Gulf War veterans meeting a validated case definition of Gulf War illness with 3 variants (called syndromes 1-3) and a control group, all selected randomly from the US Military Health Survey. Validated domain scales from the Autonomic Symptom Profile questionnaire, the Composite Autonomic Severity Score, and high-frequency heart rate variability from a 24-hour electrocardiogram. The Autonomic Symptom Profile scales were significantly elevated in all 3 syndrome groups (P< .001), primarily due to elevation of the orthostatic intolerance, secretomotor, upper gastrointestinal dysmotility, sleep dysfunction, urinary, and autonomic diarrhea symptom domains. The Composite Autonomic Severity Score was also higher in the 3 syndrome groups (P= .045), especially in syndrome 2, primarily due to a significant reduction in sudomotor function as measured by the Quantitative Sudomotor Axon Reflex Test, most significantly in the foot; the score was intermediate in the ankle and upper leg and was nonsignificant in the arm, indicating a peripheral nerve length-related deficit. The normal increase in high-frequency heart rate variability at night was absent or blunted in all 3 syndrome groups (P< .001). Autonomic symptoms are associated with objective, predominantly cholinergic autonomic deficits in the population of Gulf War veterans.

National study of suicide method in violent criminal offenders.

PubMed

Webb, R T; Qin, P; Stevens, H; Shaw, J; Appleby, L; Mortensen, P B

2013-09-05

Gaining a greater knowledge of the mechanisms and means by which violent offenders die by suicide can inform tailored preventive strategies. Using interlinked national Danish registry data we constructed a nested case-control study dataset of all adult suicides during 1994-2006: N=9708 cases and N=188,134 age and gender matched living controls. Completely ascertained International Classification of Diseases 10th revision cause-specific mortality codes were examined, with all criminal charges since 1980, and covariate information on psychiatric treatment and socio-demographics. Self-poisonings were classified as 'nonviolent' suicide and all other methods as being 'violent' ones. Compared with the general population, risk among male and female violent offenders was strongly and significantly elevated for suicide by either a violent or a nonviolent method, although the relative risk was greater for nonviolent suicide. These patterns were also observed among nonviolent offenders, albeit with smaller effect sizes. Risk was especially raised for self-poisoning with narcotics & hallucinogens. We could only examine the full range of suicide methods in male violent offenders. In these men, hanging was the most frequently used method, although risk was markedly and significantly elevated virtually across the entire range of regularly used suicide methods. We lacked sufficient statistical power for undertaking a detailed profiling of specific suicide methods among female violent offenders. Our findings indicate that comprehensive and broadly-based preventive approaches are needed for tackling the markedly raised risk of suicide by both violent and nonviolent means in this population. Their high relative risk for self-poisoning by illicit or illegal drugs underlines the importance of access to means and of prevailing subculture. Copyright © 2013 Elsevier B.V. All rights reserved.

The worsening factors of dengue hemorrhagic fever (DHF) based on cohort study with nested case-control in a tertiary hospital

NASA Astrophysics Data System (ADS)

Lardo, S.; Soesatyo, M. H. N. E.; Juffrie; Umniyati, S. R.

2018-03-01

The clinical pathway of DHF has a broad pathophysiological and pathogenesis spectrum. Clinical and laboratory characteristics are some of the parameters to determine the factors that contribute to the worsening of the disease. The objective of this study is to determine the clinical and laboratory characteristics which contribute to the worsening of DHF. The study had been conducted from January 2012-December 2014 at the general ward of the Internal Medicine Department, Indonesia Army Central Hospital Gatot Soebroto. There were 101 male patients (64.7%) and 55 female patients (35.3 %) ages ranging from 14 - 62 years old. The diagnosis was divided into: 124 patients DHF grade I, 6 DHF grade II, 20 DHF grade III and 6 with dengue shock syndrome (DSS) patients. Clinically and statistically, there were 4 variables apparently found with the severity of DHF, as follows: decreased appetite with p = 0.007 (OR 4.87), hepatomegaly with p = 0.009 (OR 27.00), systolic blood pressure with p = 0.037 (OR 0.95), and initial thrombocyte with p = 0.000 (OR 0.97). This cohort and nested case-control study found that worsening of DHF is related with decreased appetite, hepatomegaly, systolic blood pressure and initial thrombocyte count.

Comparison of the diagnostic performance of microscopic examination with nested polymerase chain reaction for optimum malaria diagnosis in Upper Myanmar.

PubMed

Kang, Jung-Mi; Cho, Pyo-Yun; Moe, Mya; Lee, Jinyoung; Jun, Hojong; Lee, Hyeong-Woo; Ahn, Seong Kyu; Kim, Tae Im; Pak, Jhang Ho; Myint, Moe Kyaw; Lin, Khin; Kim, Tong-Soo; Na, Byoung-Kuk

2017-03-16

Accurate diagnosis of Plasmodium infection is crucial for prompt malaria treatment and surveillance. Microscopic examination has been widely applied as the gold standard for malaria diagnosis in most part of malaria endemic areas, but its diagnostic value has been questioned, particularly in submicroscopic malaria. In this study, the diagnostic performance of microscopic examination and nested polymerase chain reaction (PCR) was evaluated to establish optimal malaria diagnosis method in Myanmar. A total of 1125 blood samples collected from residents in the villages and towns located in Naung Cho, Pyin Oo Lwin, Tha Beik Kyin townships and Mandalay of Upper Myanmar were screened by microscopic examination and species-specific nested PCR method. Among the 1125 blood samples, 261 samples were confirmed to be infected with malaria by microscopic examination. Evaluation of the 1125 samples by species-specific nested PCR analysis revealed that the agreement between microscopic examination and nested PCR was 87.3% (261/299). Nested PCR successfully detected 38 Plasmodium falciparum or Plasmodium vivax infections, which were missed in microscopic examination. Microscopic examinations also either misdiagnosed the infected Plasmodium species, or did not detect mixed infections with different Plasmodium species in 31 cases. The nested PCR method is more reliable than conventional microscopic examination for the diagnosis of malaria infections, and this is particularly true in cases of mixed infections and submicroscopic infections. Given the observed higher sensitivity and specificity of nested PCR, the molecular method holds enormous promise in malaria diagnosis and species differentiation, and can be applied as an effective monitoring tool for malaria surveillance, control and elimination in Myanmar.

A population-based case-control teratologic study of furazidine, a nitrofuran-derivative treatment during pregnancy.

PubMed

Czeizel, A E; Rockenbauer, M; Sørensen, H T; Olsen, J

2000-04-01

To study human teratogenic potential of furazidine treatment during pregnancy. Pair analysis of cases with congenital abnormalities and matched population controls. The Hungarian Case-Control Surveillance of Congenital Abnormalities. 38,151 pregnant women who had newborn infants without any defects (population control group) and 22,865 pregnant women who had newborns or fetuses with congenital abnormalities between 1980 and 1996. In the case group, 157 (0.7%) and in the control group, 254 (0.7%) pregnant women were treated with furazidine. The case-control pair analysis did not indicate a teratogenic potential of furazidine use during the second to third months of gestation, i.e. in the critical period for major congenital abnormalities. Treatment with furazidine during pregnancy did not show teratogenic risk to the fetus.

Lizards fail to plastically adjust nesting behavior or thermal tolerance as needed to buffer populations from climate warming.

PubMed

Telemeco, Rory S; Fletcher, Brooke; Levy, Ofir; Riley, Angela; Rodriguez-Sanchez, Yesenia; Smith, Colton; Teague, Collin; Waters, Amanda; Angilletta, Michael J; Buckley, Lauren B

2017-03-01

Although observations suggest the potential for phenotypic plasticity to allow adaptive responses to climate change, few experiments have assessed that potential. Modeling suggests that Sceloporus tristichus lizards will need increased nest depth, shade cover, or embryonic thermal tolerance to avoid reproductive failure resulting from climate change. To test for such plasticity, we experimentally examined how maternal temperatures affect nesting behavior and embryonic thermal sensitivity. The temperature regime that females experienced while gravid did not affect nesting behavior, but warmer temperatures at the time of nesting reduced nest depth. Additionally, embryos from heat-stressed mothers displayed increased sensitivity to high-temperature exposure. Simulations suggest that critically low temperatures, rather than high temperatures, historically limit development of our study population. Thus, the plasticity needed to buffer this population has not been under selection. Plasticity will likely fail to compensate for ongoing climate change when such change results in novel stressors. © 2016 John Wiley & Sons Ltd.

Spatiotemporal patterns of duck nest density and predation risk: a multi-scale analysis of 18 years and more than 10,000 nests

USGS Publications Warehouse

Ringelman, Kevin M.; Eadie, John M.; Ackerman, Joshua T.; Sih, Andrew; Loughman, Daniel L.; Yarris, Gregory S.; Oldenburger, Shaun L.; McLandress, M. Robert

2017-01-01

Many avian species are behaviorally-plastic in selecting nest sites, and may shift to new locations or habitats following an unsuccessful breeding attempt. If there is predictable spatial variation in predation risk, the process of many individuals using prior experience to adaptively change nest sites may scale up to create shifting patterns of nest density at a population level. We used 18 years of waterfowl nesting data to assess whether there were areas of consistently high or low predation risk, and whether low-risk areas increased, and high-risk areas decreased in nest density the following year. We created kernel density maps of successful and unsuccessful nests in consecutive years and found no correlation in predation risk and no evidence for adaptive shifts, although nest density was correlated between years. We also examined between-year correlations in nest density and nest success at three smaller spatial scales: individual nesting fields (10–28 ha), 16-ha grid cells and 4-ha grid cells. Here, results were similar across all scales: we found no evidence for year-to-year correlation in nest success but found strong evidence that nest density was correlated between years, and areas of high nest success increased in nest density the following year. Prior research in this system has demonstrated that areas of high nest density have higher nest success, and taken together, our results suggest that ducks may adaptively select nest sites based on the local density of conspecifics, rather than the physical location of last year's nest. In unpredictable environments, current cues, such as the presence of active conspecific nests, may be especially useful in selecting nest sites. The cues birds use to select breeding locations and successfully avoid predators deserve continued attention, especially in systems of conservation concern.

Effects of wind energy development on nesting ecology of greater prairie-chickens in fragmented grasslands.

PubMed

McNew, Lance B; Hunt, Lyla M; Gregory, Andrew J; Wisely, Samantha M; Sandercock, Brett K

2014-08-01

Wind energy is targeted to meet 20% of U.S. energy needs by 2030, but new sites for development of renewable energy may overlap with important habitats of declining populations of grassland birds. Greater Prairie-Chickens (Tympanuchus cupido) are an obligate grassland bird species predicted to respond negatively to energy development. We used a modified before-after control-impact design to test for impacts of a wind energy development on the reproductive ecology of prairie-chickens in a 5-year study. We located 59 and 185 nests before and after development, respectively, of a 201 MW wind energy facility in Greater Prairie-Chicken nesting habitat and assessed nest site selection and nest survival relative to proximity to wind energy infrastructure and habitat conditions. Proximity to turbines did not negatively affect nest site selection (β = 0.03, 95% CI = -1.2-1.3) or nest survival (β = -0.3, 95% CI = -0.6-0.1). Instead, nest site selection and survival were strongly related to vegetative cover and other local conditions determined by management for cattle production. Integration of our project results with previous reports of behavioral avoidance of oil and gas facilities by other species of prairie grouse suggests new avenues for research to mitigate impacts of energy development. © 2014 The Authors. Conservation Biology published by Wiley Periodicals, Inc. on behalf of Society for Conservation Biology.

Who are the important predators of sea turtle nests at Wreck Rock beach?

PubMed Central

Booth, David T.

2017-01-01

Excessive sea turtle nest predation is a problem for conservation management of sea turtle populations. This study assessed predation on nests of the endangered loggerhead sea turtle (Caretta caretta) at Wreck Rock beach adjacent to Deepwater National Park in Southeast Queensland, Australia after a control program for feral foxes was instigated. The presence of predators on the nesting dune was evaluated by tracking plots (2 × 1 m) every 100 m along the dune front. There were 21 (2014–2015) and 41 (2015–2016) plots established along the dune, and these were monitored for predator tracks daily over three consecutive months in both nesting seasons. Predator activities at nests were also recorded by the presence of tracks on top of nests until hatchlings emerged. In addition, camera traps were set to record the predator activity around selected nests. The tracks of the fox (Vulpes vulpes) and goanna (Varanus spp) were found on tracking plots. Tracking plots, nest tracks and camera traps indicated goanna abundance varied strongly between years. Goannas were widely distributed along the beach and had a Passive Activity Index (PAI) (0.31 in 2014–2015 and 0.16 in 2015–2016) approximately seven times higher than that of foxes (PAI 0.04 in 2014–2015 and 0.02 in 2015–2016). Five hundred and twenty goanna nest visitation events were recorded by tracks but no fox tracks were found at turtle nests. Camera trap data indicated that yellow-spotted goannas (Varanus panoptes) appeared at loggerhead turtle nests more frequently than lace monitors (V. varius) did, and further that lace monitors only predated nests previously opened by yellow-spotted goannas. No foxes were recorded at nests with camera traps. This study suggests that large male yellow-spotted goannas are the major predator of sea turtle nests at the Wreck Rock beach nesting aggregation and that goanna activity varies between years. PMID:28674666

Environmental Impacts of Wind Power Development on the Population Biology of Greater Prairie-Chickens

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sandercock, Brett K.

Executive Summary 1. We investigated the impacts of wind power development on the demography, movements, and population genetics of Greater Prairie-Chickens (Tympanuchus cupido) at three sites in northcentral and eastern Kansas for a 7-year period. Only 1 of 3 sites was developed for wind power, the 201MW Meridan Way Wind Power Facility at the Smoky Hills site in northcentral Kansas. Our project report is based on population data for prairie chickens collected during a 2-year preconstruction period (2007-2008), a 3-year postconstruction period (2009-2011) and one final year of lek surveys (2012). Where relevant, we present preconstruction data from our fieldmore » studies at reference sites in the northern Flint Hills (2007-2009) and southern Flint Hills (2006-2008). 2. We addressed seven potential impacts of wind power development on prairie chickens: lek attendance, mating behavior, use of breeding habitat, fecundity rates, natal dispersal, survival rates, and population numbers. Our analyses of pre- and postconstruction impacts are based on an analysis of covariance design where we modeled population performance as a function of treatment period, distance to eventual or actual site of the nearest wind turbine, and the interaction of these factors. Our demographic and movement data from the 6-year study period at the Smoky Hills site included 23 lek sites, 251 radio-marked females monitored for 287 bird-years, and 264 nesting attempts. Our genetic data were based on genotypes of 1,760 females, males and chicks that were screened with a set of 27 microsatellite markers that were optimized in the lab. 3. In our analyses of lek attendance, the annual probability of lek persistence during the preconstruction period was ~0.9. During the postconstruction period, distance to nearest turbine did not have a significant effect on the probability of lek persistence. However, the probability of lek persistence increased from 0.69 at 0 m to 0.89 at 30 km from turbines, and most abandoned lek sites were located <5 km from turbines. Probability of lek persistence was significantly related to habitat and number of males. Leks had a higher probability of persistence in grasslands than agricultural fields, and increased from ~0.2 for leks of 5 males, to >0.9 for leks of 10 or more males. Large leks in grasslands should be a higher priority for conservation. Overall, wind power development had a weak effect on the annual probability of lek persistence. 3. We used molecular methods to investigate the mating behavior of prairie chickens. The prevailing view for lek-mating grouse is that females mate once to fertilize the clutch and that conspecific nest parasitism is rare. We found evidence that females mate multiple times to fertilize the clutch (8-18% of broods, 4-38% of chicks) and will parasitize nests of other females during egg-laying (~17% of nests). Variable rates of parentage were highest in the fragmented landscapes at the Smoky Hills field site, and were lower at the Flint Hills field site. Comparisons of the pre- and postconstruction periods showed that wind energy development did not affect the mating behaviors of prairie chickens. 4. We examined use of breeding habitats by radio-marked females and conducted separate analyses for nest site selection, and movements of females not attending nests or broods. The landscape was a mix of native prairie and agricultural habitats, and nest site selection was not random because females preferred to nest in grasslands. Nests tended to be closer to turbines during the postconstruction period and there was no evidence of behavioral avoidance of turbines by females during nest site selection. Movements of females not attending nests or broods showed that females crossed the site of the wind power development at higher rates during the preconstruction period (20%) than the postconstruction period (11%), and that movements away from turbines were more frequent during the postconstruction period. Thus, wind power development appears to affect movements in breeding habitats but not nest site selection of female prairie chickens during the breeding season. 5. We tested the effects of wind power development on five components of female fecundity: timing of clutch initiation, clutch size of first nests and renests, nest survival, and hatchability of eggs. Average date of clutch initiation was 26 April, clutch size was 12.7 and 10.6 eggs for first nests and renests, probability of nest survival was low at 0.18, but egg hatchability was high at 0.79. Wind power development had no impact on reproductive effort or nesting success, and all five components of fecundity were not related to treatment period or distance to turbine. Nest survival was the main factor limiting reproductive output of female prairie chickens and most losses were due to predation. Daily nest survival was strongly related to vegetative cover at the nest. Changes to rangeland management practices that would double nesting cover from 2.5 to 5 dm would triple the probability of nest survival from 0.17 to 0.52. Grass and forb cover had weak positive effects on daily nest survival whereas shrub cover, proximity to woodlands, and recent rainfall had negative effects. Reproductive performance of prairie chickens is low in managed rangelands in northcentral Kansas and efforts to improve range conditions and reduce predator activity would aid recovery of prairie chicken populations. 6. We used molecular methods to investigate patterns of natal dispersal in prairie chickens. High rates of nest failure limited the number of young that we could sample. Direct detections of natal dispersal were limited because survival of newly hatched chicks to become adults were low and because we were unable to detect dispersal distances outside of our study area. Direct observations of natal movements were limited and were inadequate to make conclusions about the potential impacts of wind energy development on natal dispersal. Spatial correlograms of genetic distance among males at leks were a more sensitive measure of population structure, and indicated a weak effect of wind energy development on the spatial genetic structure of prairie chickens. 7. We tested the effects of wind power development on female survival with time-to-event models, and on residual body mass of males with analyses of covariance. Distance to turbine and the interaction of distance and treatment period had no effect on female survival. Contrary to predictions of negative impacts of wind power development, the probability of female was lowest during the preconstruction period (0.274) and increased significantly during the postconstruction period (0.543). Inspection of hazard functions indicated that the difference in annual survival could be attributed to a higher risk of mortality during the lekking season in the preconstruction period. We suggest that wind power development may have improved ecological conditions for prairie chickens by disrupting the foraging behavior of diurnal raptors that kill prairie chickens at lek sites. In support of this idea, raptor kills tended to be farther from turbines during the postconstruction period whereas mammalian kills were closer. Analyses of the major causes of mortality did not support our hypothesis because the odds of raptor predation were greater after development was completed. Most mortality losses of radio-marked females were due to predation, and losses to collision mortality or harvest were rare events. Low rates of natural mortality during fall and winter imply that harvest is likely to be additive mortality in prairie chickens. Wind energy development reduced the residual body mass of male Greater Prairie-Chickens at lek sites near turbines. Low values of residual body mass could have a negative impact on individual survival or fecundity rates, or may be related to predation risk and flight performance of males displaying at open lek sites. 8. We tested for impacts of wind power development on population numbers of prairie chickens with monitoring of male numbers at leks, and with genetic measures of population structure. Lek counts indicated that wind power development did not affect the population size of prairie chickens. Peak counts of males at leks were recorded the first year after construction was completed and the highest rates of population change were observed during the interval when the wind power facility was constructed. Population numbers of prairie chickens near and distant from turbines appeared to covary in parallel, probably because bird numbers were linked by dispersal movements. Estimates of population viability based on genetic diversity, effective population size and rates of population exchange did not show annual changes and were unaffected by wind development during our study. Estimates of relatedness among males at the same and different leks suggested that wind power development has either reduced dispersal rates or changed settlement patterns, leading to higher rates of relatedness among males displaying at the same lek site. 9. Greater Prairie-Chickens were not strongly affected by wind power development in Kansas. Negative impacts of wind power development included a trend for reductions in lek persistence near turbines, behavioral avoidance of turbines by females during their breeding season movements, and changes in the genetic structure of males at leks that were consistent with reduced dispersal or recruitment rates. We found no impacts of wind power development on nest site selection, female reproductive effort or nesting success, or population numbers. Positive impacts of wind power development included an increase in female survival rates. We hypothesized that the unexpected increase in female survival was related to changes in trophic interactions and disruption of the foraging behavior of raptors that kill prairie chickens at lek site. 10. Research funding for this project included a grant from the 20% Wind by 2030 Program of the Department of Energy (this final report), and grants from the Kansas Department of Wildlife, Parks and Tourism, the National Fish and Wildlife Federation, and initial funding from the National Wind Coordinating Collaborative. Research products from data collected during the preconstruction period have included five peer-reviewed research articles and two PhD dissertations at Kansas State University. Additional manuscripts are in review for possible publication in 2013-2014.« less

Use of the superpopulation approach to estimate breeding population size: An example in asynchronously breeding birds

USGS Publications Warehouse

Williams, K.A.; Frederick, P.C.; Nichols, J.D.

2011-01-01

Many populations of animals are fluid in both space and time, making estimation of numbers difficult. Much attention has been devoted to estimation of bias in detection of animals that are present at the time of survey. However, an equally important problem is estimation of population size when all animals are not present on all survey occasions. Here, we showcase use of the superpopulation approach to capture-recapture modeling for estimating populations where group membership is asynchronous, and where considerable overlap in group membership among sampling occasions may occur. We estimate total population size of long-legged wading bird (Great Egret and White Ibis) breeding colonies from aerial observations of individually identifiable nests at various times in the nesting season. Initiation and termination of nests were analogous to entry and departure from a population. Estimates using the superpopulation approach were 47-382% larger than peak aerial counts of the same colonies. Our results indicate that the use of the superpopulation approach to model nesting asynchrony provides a considerably less biased and more efficient estimate of nesting activity than traditional methods. We suggest that this approach may also be used to derive population estimates in a variety of situations where group membership is fluid. ?? 2011 by the Ecological Society of America.

Integrating spatial data and shorebird nesting locations to predict the potential future impact of global warming on coastal habitats: A case study on Farasan Islands, Saudi Arabia.

PubMed

Alrashidi, Monif; Shobrak, Mohammed; Al-Eissa, Mohammed S; Székely, Tamás

2012-07-01

One of the expected effects of the global warming is changing coastal habitats by accelerating the rate of sea level rise. Coastal habitats support large number of marine and wetland species including shorebirds (plovers, sandpipers and allies). In this study, we investigate how coastal habitats may be impacted by sea level rise in the Farasan Islands, Kingdom of Saudi Arabia. We use Kentish plover Charadrius alexandrinus - a common coastal breeding shorebird - as an ecological model species to predict the influence of sea level rise. We found that any rise of sea level is likely to inundate 11% of Kentish plover nests. In addition, 5% of the coastal areas of Farasan Islands, which support 26% of Kentish plover nests, will be flooded, if sea level rises by one metre. Our results are constrained by the availability of data on both elevation and bird populations. Therefore, we recommend follow-up studies to model the impacts of sea level rise using different elevation scenarios, and the establishment of a monitoring programme for breeding shorebirds and seabirds in Farasan Islands to assess the impact of climate change on their populations.

Brain cancer and nonoccupational risk factors: a case-control study among workers at two nuclear facilities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carpenter, A.V.; Flanders, W.D.; Frome, E.L.

1987-09-01

In a nested case-control study of nuclear workers, 82 brain cancer cases were compared with 328 matched controls to investigate the possible association with nonoccupational risk factors such as histories of epilepsy or head injury. We observed a moderately strong association between brain cancer occurrence and history of epilepsy (OR = 5.7, 95 per cent CI: 1.0, 32.1), but did not find a positive association with previous head injury (OR = 0.9, 95 per cent CI: 0.2, 4.2).

PARTITIONING RISK AMONG DIFFERENT SOURCES OF NEST FAILURE

EPA Science Inventory

Nest predation and nest parasitism receive the most attention as causes of nest failure for North American songbirds. Yet for many populations, interspecific competition, adverse weather, abandonment, nestling starvation, and

egg failure may also be significant causes of n...

Ducks and passerines nesting in northern mixed-grass prairie treated with fire

USGS Publications Warehouse

Grant, Todd A.; Shaffer, Terry L.; Madden, Elizabeth M.; Berkey, Gordon B.

2011-01-01

Prescribed fire is an important, ecology-driven tool for restoration of grassland systems. However, prescribed fire remains controversial for some grassland managers because of reported reductions in bird use of recently burned grasslands. Few studies have evaluated effects of fire on grassland bird populations in the northern mixed-grass prairie region. Fewer studies yet have examined the influence of fire on nest density or survival. In our review, we found no studies that simultaneously examined effects of fire on duck and passerine nesting. During 1998—2003, we examined effects of prescribed fire on the density of upland-nesting ducks and passerines nesting in north-central North Dakota, USA. Apparent nest densities of gadwall (Anas strepera), mallard (A. platyrhynchos), and all duck species combined, were influenced by fire history of study units, although the degree of influence was not compelling. Fire history was not related to nest densities of blue-winged teal (A. discors), northern shoveler (A. clypeata), or northern pintail (A. acuta); however, apparent nest densities in relation to the number of postfire growing seasons exhibited a strikingly similar pattern among all duck species. When compared to ducks, fire history strongly influenced apparent nest densities of clay-colored sparrow (Spizella pallida), Savannah sparrow (Passerculus sandwichensis), and bobolink (Dolichonyx oryzivorus). For most species examined, apparent nest densities were lowest in recently burned units, increased during the second postfire growing season, and stabilized or, in some cases, decreased thereafter. Prescribed fire is critical for restoring the ecology of northern mixed-grass prairies and our findings indicate that reductions in nest densities are limited mostly to the first growing season after fire. Our results support the premise that upland-nesting ducks and several grassland passerine species are adapted to periodic fires occurring at a frequency similar to that of pre-Euro-American settlement of the region.

Development of an In-House Multiplex Nested RT-PCR Method for Detecting Acute HIV-1 Infection in High Risk Populations.

PubMed

Liu, Zhiying; Li, Wei; Xu, Meng; Sheng, Bo; Yang, Zixuan; Jiao, Yanmei; Zhang, Tong; Mou, Danlei; Chen, Dexi; Wu, Hao

2015-01-01

The detection of acute HIV infection (AHI) among high risk populations can help reduce secondary transmission of HIV. The nucleic acid testing (NAT) can shorten the test window period by up to 7-12 days. In this study, we describe an in-house NAT based on the multiplex nested RT-PCR method to detect the HIV RNA. We also evaluated it in a high risk cohort in Beijing. Four primer pairs were designed and evaluated for the detection of different HIV-1 subtypes in group M. Multiplex RT-PCR and nested PCR were performed. The sensitivity, specialty, primers compatibility among HIV subtypes were evaluated simultaneously. In an MSM cohort in Beijing during a 3-year period, a total of 11,808 blood samples that were negative by ELISA or indeterminate by Western blot were analyzed by this multiplex nested RT-PCR with pooling strategy. The multiplex nested RT-PCR was successfully applied for the detection of at least six HIV-1 subtypes. The sensitivity was 40 copies/ml and the specificity was 100%. A total of 29 people were tested HIV-1 positive with acute infection in a MSM cohort of Beijing during a 3 years period. This multiplex nested RT-PCR provides a useful tool for the rapid detection of acute HIV-1 infection. When used in combination with the 3(rd) generation ELISA, it can improve the detection rate of HIV infection, especially in the source limited regions.

Diet-related risk factors for gastric dilatation-volvulus in dogs of high-risk breeds.

PubMed

Raghavan, Malathi; Glickman, Nita; McCabe, George; Lantz, Gary; Glickman, Lawrence T

2004-01-01

A nested case-control study was conducted among 1634 dogs with complete diet information in a 5-year prospective study to determine diet-related risk factors for gastric dilatation-volvulus (GDV). Cases included 106 dogs that developed GDV; controls included 212 dogs without GDV that were frequency matched to cases by year of GDV onset. Proportionate energy consumed from major food types and from carbohydrates was determined. Dogs were categorized as consuming either a low volume or high volume of food based on the median number of cups of food fed per kg of body weight per meal. Dogs fed a larger volume of food per meal were at a significantly (P<0.05) increased risk of GDV, regardless of the number of meals fed daily. For both large- and giant-breed dogs, the risk of GDV was highest for dogs fed a larger volume of food once daily.

Do spotless starlings place feathers at their nests by ultraviolet color?

PubMed

Avilés, Jesús M; Parejo, Deseada; Pérez-Contreras, Tomás; Navarro, Carlos; Soler, Juan J

2010-02-01

A considerable number of bird species carry feathers to their nests. Feathers' presence in the nests has traditionally been explained by their insulating properties. Recently, however, it has been suggested that feathers carried to the nests by females of the spotted starling (Sturnus unicolor L.) could have an ornamental function based on their ultraviolet (300-400 nm) and human-visible longer wavelength (400-700 nm) coloration. In our population, 95.7% of feathers found inside next-boxes occupied by nesting starlings were rock dove fly feathers. Of these feathers, 82.7% were naturally positioned with their reverse side oriented toward the entrance hole and 42.4% of all found feathers were situated within the nest-cup. Here we experimentally assess the signaling function of ultraviolet coloration of feathers in nests of spotless starlings by providing nests with a number of pigeon flight feathers that were respectively treated on their obverse, reverse, both, or neither side with a UV blocker. Starlings placed 42.5% of the experimental feathers in the nest-cup irrespective of the UV block treatment. Orientation of feathers toward the entrance hole was not related with their ultraviolet radiation. However, feathers placed within the nest-cup were more likely found with their reverse side oriented toward the entrance hole confirming our correlative findings. These results suggest a minor role of ultraviolet coloration on feather location by spotless starlings.

Do spotless starlings place feathers at their nests by ultraviolet color?

NASA Astrophysics Data System (ADS)

Avilés, Jesús M.; Parejo, Deseada; Pérez-Contreras, Tomás; Navarro, Carlos; Soler, Juan J.

2010-02-01

A considerable number of bird species carry feathers to their nests. Feathers’ presence in the nests has traditionally been explained by their insulating properties. Recently, however, it has been suggested that feathers carried to the nests by females of the spotted starling ( Sturnus unicolor L.) could have an ornamental function based on their ultraviolet (300-400 nm) and human-visible longer wavelength (400-700 nm) coloration. In our population, 95.7% of feathers found inside next-boxes occupied by nesting starlings were rock dove fly feathers. Of these feathers, 82.7% were naturally positioned with their reverse side oriented toward the entrance hole and 42.4% of all found feathers were situated within the nest-cup. Here we experimentally assess the signaling function of ultraviolet coloration of feathers in nests of spotless starlings by providing nests with a number of pigeon flight feathers that were respectively treated on their obverse, reverse, both, or neither side with a UV blocker. Starlings placed 42.5% of the experimental feathers in the nest-cup irrespective of the UV block treatment. Orientation of feathers toward the entrance hole was not related with their ultraviolet radiation. However, feathers placed within the nest-cup were more likely found with their reverse side oriented toward the entrance hole confirming our correlative findings. These results suggest a minor role of ultraviolet coloration on feather location by spotless starlings.

Relatedness and nesting dispersion within breeding populations of greater white-fronted geese

USGS Publications Warehouse

Fowler, A.C.; Eadie, J.M.; Ely, Craig R.

2004-01-01

We studied patterns of relatedness and nesting dispersion in female Pacific Greater White-fronted Geese (Anser albifrons frontalis) in Alaska. Female Greater White-fronted Geese are thought to be strongly philopatric and are often observed nesting in close association with other females. Analysis of the distribution of nests on the Yukon-Kuskokwim Delta in 1998 indicated that nests were significantly clumped. We tested the hypothesis that females in the same nest cluster would be closely related using estimates of genetic relatedness based on six microsatellite DNA loci. There was no difference in the mean relatedness of females in the same cluster compared to females found in different clusters. However, relatedness among females was negatively correlated with distance between their nests, and geese nesting within 50 m of one another tended to be more closely related than those nesting farther apart. Randomization tests revealed that pairs of related individuals (R > 0.45) were more likely to occur in the same cluster when analyzed at the scale of the entire study site. However, the pattern did not hold when restricted to pairs found within 500 m of each other. Our results indicate that nest clusters are not composed primarily of closely related females, but Greater White-fronted Geese appear to be sufficiently philopatric to promote nonrandom patterns of relatedness at a local scale.

Risk factors for CKD in persons with kidney stones: a case-control study in Olmsted County, Minnesota.

PubMed

Saucier, Nathan A; Sinha, Mukesh K; Liang, Kelly V; Krambeck, Amy E; Weaver, Amy L; Bergstralh, Eric J; Li, Xujian; Rule, Andrew D; Lieske, John C

2010-01-01

Kidney stones are associated with increased risk of chronic kidney disease (CKD); however, risk factors in the general community are poorly defined. A nested case-control study was performed in residents of Olmsted County, MN, who presented with a kidney stone at the Mayo Clinic in 1980-1994 to contrast patients with kidney stones who developed CKD with a group that did not. Participants were selected from the Rochester Epidemiology Project, an electronic linkage system among health care providers in Olmsted County, MN. Cases were identified by diagnostic code for CKD and confirmed to have an estimated glomerular filtration rate < 60 mL/min/1.73 m(2). Controls were matched 2:1 to cases for age, sex, date of first kidney stone, and length of medical record. Charts were abstracted to characterize stone disease, hypertension, diabetes, obesity, tobacco use, ileal conduit, symptomatic stones, type and number of stones, urinary tract infections, number and type of surgical procedures, and medical therapy. Kidney stone patients with CKD were compared with matched stone patients without CKD. There were 53 cases and 106 controls with a mean age of 57 years at first stone event and 59% men. In kidney stone patients, cases with CKD were significantly more likely (P < 0.05) than controls to have had a history of diabetes (41.5% vs 17.0%), hypertension (71.7% vs 49.1%), frequent urinary tract infections (22.6% vs 6.6%), struvite stones (7.5% vs 0%), and allopurinol use (32.1% vs 4.7%) based on univariate analysis. Potential limitations include limited statistical power to detect associations, incomplete data from 24-hour urine studies, and that stone composition was not always available. As in the general population, hypertension and diabetes are associated with increased risk of CKD in patients with kidney stones. However, other unique predictors were identified in patients with kidney stones that increased the possibility of CKD. Further studies are warranted to elucidate the nature of these associations. Copyright 2009 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

Neuropsychologic assessment of a population-based sample of Gulf War veterans.

PubMed

Wallin, Mitchell T; Wilken, Jeffrey; Alfaro, Mercedes H; Rogers, Catherine; Mahan, Clare; Chapman, Julie C; Fratto, Timothy; Sullivan, Cynthia; Kang, Han; Kane, Robert

2009-09-01

The objective of this project was to compare neuropsychologic performance and quality of life in a population-based sample of deployed Gulf War (GW) veterans with and without multisymptom complaints. The study participants were obtained from the 30,000 member population-based National Health Survey of GW-era veterans conducted in 1995. Cases (N=25) were deployed to the year 1990 and 1991 GW and met Center for Disease Control and Prevention criteria for multisymptom GW illness (GWI). Controls (N=16) were deployed to the 1990 and 1991 GW but did not meet Center for Disease Control and Prevention criteria for GWI. There were no significant differences in composite scores on the traditional and computerized neuropsychologic battery (automated neuropsychologic assessment metrics) between GW cases and controls using bivariate techniques. Multiple linear regression analyses controlling for demographic and clinical variables revealed composite automated neuropsychologic assessment metrics scores were associated with age (b=-7.8; P=0.084), and education (b=22.9; P=0.0012), but not GW case or control status (b=-63.9; P=0.22). Compared with controls, GW cases had significantly more impairment on the Personality Assessment Inventory and the short form-36. Compared with GW controls, GW cases meeting criteria for GWI had preserved cognition function but had significant psychiatric symptoms and lower quality of life.

Ecological factors related to the widespread distribution of sylvatic Rhodnius ecuadoriensis populations in southern Ecuador

PubMed Central

2012-01-01

Background Chagas disease transmission risk is a function of the presence of triatomines in domestic habitats. Rhodnius ecuadoriensis is one of the main vectors implicated in transmission of Trypanosoma cruzi in Ecuador. This triatomine species is present in domestic, peridomestic and sylvatic habitats in the country. To determine the distribution of sylvatic populations of R. ecuadoriensis and the factors related to this distribution, triatomine searches were conducted between 2005 and 2009 in southern Ecuador. Methods Manual triatomine searches were conducted by skilled bug collectors in 23 communities. Sylvatic searched sites were selected by a) directed sampling, where microhabitats were selected by the searchers and b) random sampling, where sampling points where randomly generated. Domiciliary triatomine searches were conducted using the one man-hour method. Natural trypanosome infection was determined by microscopic examination and PCR. Generalized linear models were used to test the effect of environmental factors on the presence of sylvatic triatomines. Results In total, 1,923 sylvatic individuals were collected representing a sampling effort of 751 man-hours. Collected sylvatic triatomines were associated with mammal and bird nests. The 1,219 sampled nests presented an infestation index of 11.9%, a crowding of 13 bugs per infested nest, and a colonization of 80% of the nests. Triatomine abundance was significantly higher in squirrel (Sciurus stramineus) nests located above five meters from ground level and close to the houses. In addition, 8.5% of the 820 examined houses in the same localities were infested with triatomines. There was a significant correlation between R. ecuadoriensis infestation rates found in sylvatic and synanthropic environments within communities (p = 0.012). Parasitological analysis revealed that 64.7% and 15.7% of the sylvatic bugs examined (n = 300) were infected with Trypanosoma cruzi and T. rangeli respectively, and 8% of the bugs presented mixed infections. Conclusions The wide distribution of sylvatic R. ecuadoriensis populations may jeopardize the effectiveness of control campaigns conducted to eliminate domestic populations of this species. Also, the high T. cruzi infection rates found in sylvatic R. ecuadoriensis populations in southern Ecuador could constitute a risk for house re-infestation and persistent long-term Chagas disease transmission in the region. PMID:22243930

Ecological factors related to the widespread distribution of sylvatic Rhodnius ecuadoriensis populations in southern Ecuador.

PubMed

Grijalva, Mario J; Suarez-Davalos, Victoria; Villacis, Anita G; Ocaña-Mayorga, Sofia; Dangles, Olivier

2012-01-13

Chagas disease transmission risk is a function of the presence of triatomines in domestic habitats. Rhodnius ecuadoriensis is one of the main vectors implicated in transmission of Trypanosoma cruzi in Ecuador. This triatomine species is present in domestic, peridomestic and sylvatic habitats in the country. To determine the distribution of sylvatic populations of R. ecuadoriensis and the factors related to this distribution, triatomine searches were conducted between 2005 and 2009 in southern Ecuador. Manual triatomine searches were conducted by skilled bug collectors in 23 communities. Sylvatic searched sites were selected by a) directed sampling, where microhabitats were selected by the searchers and b) random sampling, where sampling points where randomly generated. Domiciliary triatomine searches were conducted using the one man-hour method. Natural trypanosome infection was determined by microscopic examination and PCR. Generalized linear models were used to test the effect of environmental factors on the presence of sylvatic triatomines. In total, 1,923 sylvatic individuals were collected representing a sampling effort of 751 man-hours. Collected sylvatic triatomines were associated with mammal and bird nests. The 1,219 sampled nests presented an infestation index of 11.9%, a crowding of 13 bugs per infested nest, and a colonization of 80% of the nests. Triatomine abundance was significantly higher in squirrel (Sciurus stramineus) nests located above five meters from ground level and close to the houses. In addition, 8.5% of the 820 examined houses in the same localities were infested with triatomines. There was a significant correlation between R. ecuadoriensis infestation rates found in sylvatic and synanthropic environments within communities (p = 0.012). Parasitological analysis revealed that 64.7% and 15.7% of the sylvatic bugs examined (n = 300) were infected with Trypanosoma cruzi and T. rangeli respectively, and 8% of the bugs presented mixed infections. The wide distribution of sylvatic R. ecuadoriensis populations may jeopardize the effectiveness of control campaigns conducted to eliminate domestic populations of this species. Also, the high T. cruzi infection rates found in sylvatic R. ecuadoriensis populations in southern Ecuador could constitute a risk for house re-infestation and persistent long-term Chagas disease transmission in the region.

Indirect food web interactions mediated by predator–rodent dynamics: relative roles of lemmings and voles

PubMed Central

Ims, Rolf A.; Henden, John-André; Thingnes, Anders V.; Killengreen, Siw T.

2013-01-01

Production cycles in birds are proposed as prime cases of indirect interactions in food webs. They are thought to be driven by predators switching from rodents to bird nests in the crash phase of rodent population cycles. Although rodent cycles are geographically widespread and found in different rodent taxa, bird production cycles appear to be most profound in the high Arctic where lemmings dominate. We hypothesized that this may be due to arctic lemmings inducing stronger predator responses than boreal voles. We tested this hypothesis by estimating predation rates in dummy bird nests during a rodent cycle in low-Arctic tundra. Here, the rodent community consists of a spatially variable mix of one lemming (Lemmus lemmus) and two vole species (Myodes rufocanus and Microtus oeconomus) with similar abundances. In consistence with our hypothesis, lemming peak abundances predicted well crash-phase nest predation rates, whereas the vole abundances had no predictive ability. Corvids were found to be the most important nest predators. Lemmings appear to be accessible to the whole predator community which makes them particularly powerful drivers of food web dynamics. PMID:24173526

Combining matched and unmatched control groups in case-control studies.

PubMed

le Cessie, Saskia; Nagelkerke, Nico; Rosendaal, Frits R; van Stralen, Karlijn J; Pomp, Elisabeth R; van Houwelingen, Hans C

2008-11-15

Multiple control groups in case-control studies are used to control for different sources of confounding. For example, cases can be contrasted with matched controls to adjust for multiple genetic or unknown lifestyle factors and simultaneously contrasted with an unmatched population-based control group. Inclusion of different control groups for a single exposure analysis yields several estimates of the odds ratio, all using only part of the data. Here the authors introduce an easy way to combine odds ratios from several case-control analyses with the same cases. The approach is based upon methods used for meta-analysis but takes into account the fact that the same cases are used and that the estimated odds ratios are therefore correlated. Two ways of estimating this correlation are discussed: sandwich methodology and the bootstrap. Confidence intervals for the pooled estimates and a test for checking whether the odds ratios in the separate case-control studies differ significantly are derived. The performance of the method is studied by simulation and by applying the methods to a large study on risk factors for thrombosis, the MEGA Study (1999-2004), wherein cases with first venous thrombosis were included with a matched control group of partners and an unmatched population-based control group.

Orientation and navigation during adult transport between nests in the ant Cataglypis iberica.

PubMed

Fourcassie, V; Dahbi, A; Cerdá, X

2000-08-01

Cataglyphis iberica is a polydomous ant species in which adult transports between nests are frequently observed. When pairs of workers were captured and released at the same location, the transporters (Ts) field directly towards their destination nest and reached it in most of the cases. The transportees (Te), on the other hand, fled in the opposite direction and only a third of them eventually reached their nest of departure. Additional experiments suggest that this result may be explained by the fact that the Ts ants have a memory of the compass direction of the nest they are heading to and that they adjust their course by using a sequence of memorised landmarks. As regards to the Te, the reversal of their direction of transport seems to be based essentially on celestial cues.

Reproductive biology of Pleurodema guayapae (Anura: Leptodactylidae: Leiuperinae).

PubMed

Valetti, Julián Alonso; Grenat, Pablo Raúl; Baraquet, Mariana; Martino, Adolfo Ludovico

2014-03-01

Pleurodema guayapae is a species that inhabits saline environments and semidesert zones from central Argentina. To date, the knowledge about the reproductive biology of this species is very poor, and our aim is to contribute to its knowledge with the description of some important reproductive aspects. For this, field work was undertaken in an area near to Patquia, La Rioja province. Sampling was undertaken during three summer periods (2006-2007; 2007-2008; 2008-2009) in Chamical-Patquia area, where we could find reproductively active populations. We observed and described breeding sites, type of clutch, process of foam nest construction, clutch and egg number and sizes, and hatching time and stage. Behaviour observations were performed from the time that males began to call until the pairs ended up the foam nests building, and layed the eggs. Additionally, one amplected pair was observed and filmed in the process of foam nest construction, and four amplectant pairs were collected and separatelly placed in plastic containers, for nests observations in the laboratory. Hatching time was based on three different foam nests of known age. We found that P. guayapae populations were acoustically active only after a rainfall. Its breeding sites were represented by ephemeral ponds of fresh water, product of rains. The males emitted their calls inside or outside these ponds. A detailed description of the foam nest construction process by both females and males was made. The clutches were in dome-shaped foam nest type of 6-9cm in diameter and 1-3cm in height, some of which were in communal nests. The nests had an average of 1 137 pigmented eggs. This species showed a short hatching time. Our results allow us to conclude that this species should be considered an extreme explosive breeder. Our results are discussed with others obtained for related species.

Reconstructing paternal genotypes to infer patterns of sperm storage and sexual selection in the hawksbill turtle.

PubMed

Phillips, Karl P; Jorgensen, Tove H; Jolliffe, Kevin G; Jolliffe, San-Marie; Henwood, Jock; Richardson, David S

2013-04-01

Postcopulatory sperm storage can serve a range of functions, including ensuring fertility, allowing delayed fertilization and facilitating sexual selection. Sperm storage is likely to be particularly important in wide-ranging animals with low population densities, but its prevalence and importance in such taxa, and its role in promoting sexual selection, are poorly known. Here, we use a powerful microsatellite array and paternal genotype reconstruction to assess the prevalence of sperm storage and test sexual selection hypotheses of genetic biases to paternity in one such species, the critically endangered hawksbill turtle, Eretmochelys imbricata. In the majority of females (90.7%, N = 43), all offspring were sired by a single male. In the few cases of multiple paternity (9.3%), two males fertilized each female. Importantly, the identity and proportional fertilization success of males were consistent across all sequential nests laid by individual females over the breeding season (up to five nests over 75 days). No males were identified as having fertilized more than one female, suggesting that a large number of males are available to females. No evidence for biases to paternity based on heterozygosity or relatedness was found. These results indicate that female hawksbill turtles are predominantly monogamous within a season, store sperm for the duration of the nesting season and do not re-mate between nests. Furthermore, females do not appear to be using sperm storage to facilitate sexual selection. Consequently, the primary value of storing sperm in marine turtles may be to uncouple mating and fertilization in time and avoid costly re-mating. © 2013 Blackwell Publishing Ltd.

Cancer risk in the rubber industry: a review of the recent epidemiological evidence

PubMed Central

Kogevinas, M.; Sala, M.; Boffetta, P.; Kazerouni, N.; Kromhout, H.; Hoar-Zahm, S.

1998-01-01

OBJECTIVES: To examine the recent epidemiological evidence on cancer risk among workers in the rubber industry. METHODS: Epidemiological studies published after the last detailed review by the International Agency for Research on Cancer (IARC) in 1982 were reviewed. 12 cohort studies in nine countries that examined distinct populations of workers in the rubber industry, seven industry based nested case-control studies, 48 community based case-control studies in 16 countries, and 23 studies based on administrative data that reported risks for employment in the rubber industry were identified. RESULTS: Excess risks of bladder cancer, lung cancer, and leukaemia were found in most studies, with risks above 1.5 in about half of the studies. A moderate excess risk for laryngeal cancer was consistent across studies. Excess risks were found in a few studies for cancers of the oesophagus, stomach, colon, liver, pancreas, skin, prostate, kidney, brain, and thyroid, and for malignant lymphoma and multiple myeloma, but overall results were not consistent for these neoplasms. CONCLUSIONS: Magnitude of the observed risks varied considerably between studies, but overall the findings indicate the presence of a widespread moderate increased cancer risk among rubber workers. The most consistent results were for bladder, laryngeal, and lung cancer and for leukaemia. Excess risks were also found for other neoplasms but an evaluation of the consistency of the findings is difficult because of the possible selective reporting of results. Recent studies do not provide information associating specific exposures with cancer risk. The preventive measures taken in the rubber industry in recent years may decrease risks, but this has not been documented yet in epidemiological studies.   PMID:9536156

Polygenic Risk Score, Parental Socioeconomic Status, Family History of Psychiatric Disorders, and the Risk for Schizophrenia: A Danish Population-Based Study and Meta-analysis.

PubMed

Agerbo, Esben; Sullivan, Patrick F; Vilhjálmsson, Bjarni J; Pedersen, Carsten B; Mors, Ole; Børglum, Anders D; Hougaard, David M; Hollegaard, Mads V; Meier, Sandra; Mattheisen, Manuel; Ripke, Stephan; Wray, Naomi R; Mortensen, Preben B

2015-07-01

Schizophrenia has a complex etiology influenced both by genetic and nongenetic factors but disentangling these factors is difficult. To estimate (1) how strongly the risk for schizophrenia relates to the mutual effect of the polygenic risk score, parental socioeconomic status, and family history of psychiatric disorders; (2) the fraction of cases that could be prevented if no one was exposed to these factors; (3) whether family background interacts with an individual's genetic liability so that specific subgroups are particularly risk prone; and (4) to what extent a proband's genetic makeup mediates the risk associated with familial background. We conducted a nested case-control study based on Danish population-based registers. The study consisted of 866 patients diagnosed as having schizophrenia between January 1, 1994, and December 31, 2006, and 871 matched control individuals. Genome-wide data and family psychiatric and socioeconomic background information were obtained from neonatal biobanks and national registers. Results from a separate meta-analysis (34,600 cases and 45,968 control individuals) were applied to calculate polygenic risk scores. Polygenic risk scores, parental socioeconomic status, and family psychiatric history. Odds ratios (ORs), attributable risks, liability R2 values, and proportions mediated. Schizophrenia was associated with the polygenic risk score (OR, 8.01; 95% CI, 4.53-14.16 for highest vs lowest decile), socioeconomic status (OR, 8.10; 95% CI, 3.24-20.3 for 6 vs no exposures), and a history of schizophrenia/psychoses (OR, 4.18; 95% CI, 2.57-6.79). The R2 values were 3.4% (95% CI, 2.1-4.6) for the polygenic risk score, 3.1% (95% CI, 1.9-4.3) for parental socioeconomic status, and 3.4% (95% CI, 2.1-4.6) for family history. Socioeconomic status and psychiatric history accounted for 45.8% (95% CI, 36.1-55.5) and 25.8% (95% CI, 21.2-30.5) of cases, respectively. There was an interaction between the polygenic risk score and family history (P = .03). A total of 17.4% (95% CI, 9.1-26.6) of the effect associated with family history of schizophrenia/psychoses was mediated through the polygenic risk score. Schizophrenia was associated with the polygenic risk score, family psychiatric history, and socioeconomic status. Our study demonstrated that family history of schizophrenia/psychoses is partly mediated through the individual's genetic liability.

25-Hydroxy vitamin-D, obesity, and associated variables as predictors of breast cancer risk and tamoxifen benefit in NSABP-P1.

PubMed

Amir, Eitan; Cecchini, Reena S; Ganz, Patricia A; Costantino, Joseph P; Beddows, Samantha; Hood, Nicola; Goodwin, Pamela J

2012-06-01

Observational studies suggest that host factors are associated with breast cancer risk. The influence of obesity, vitamin-D status, insulin resistance, inflammation, and elevated adipocytokines in women at high risk of breast cancer is unknown. The NSABP-P1 trial population was used for a nested case-control study. Cases were drawn from those who developed invasive breast cancer and controls selected from unaffected participants (≤4 per case) matched for age, race, 5 year Gail score, and geographic location of clinical center as a surrogate for latitude. Fasting serum banked at trial enrolment was assayed for 25-hydroxy vitamin-D (25OHD), insulin, leptin (adipocytokine), and C-reactive protein (CRP, marker of inflammation). Logistic regression was used to test for associations between study variables and the risk of invasive breast cancer. Two hundred and thirty-one cases were matched with 856 controls. Mean age was 54, and 49% were premenopausal. There were negative correlations for 25OHD with body mass index (BMI), insulin, CRP, and leptin. BMI ≥ 25 kg/m(2) was associated with higher breast cancer risk (odds ratio [OR] 1.45, p = 0.02) and tamoxifen treatment was associated with lower risk (OR = 0.44, p < 0.001). Suboptimal 25OHD (<72 nmol/l) did not influence breast cancer risk (OR = 1.06, p = 0.76). When evaluated as continuous variables, 25OHD, insulin, CRP, and leptin levels were not associated with breast cancer risk (all p > 0.34). In this high risk population, higher BMI was associated with a greater breast cancer risk. Serum levels of 25OHD, insulin, CRP, and leptin were not independent predictors of either breast cancer risk or tamoxifen benefit.

Habitat Selection and Reproductive Success of Lewis's Woodpecker (Melanerpes lewis) at Its Northern Limit

PubMed Central

Zhu, Xiang; Srivastava, Diane S.; Martin, Kathy

2012-01-01

Lewis's Woodpecker (Melanerpes lewis) has experienced population declines in both Canada and the United States and in 2010 was assigned a national listing of threatened in Canada. We conducted a two-year study (2004–2005) of this species at its northern range limit, the South Okanagan Valley in British Columbia, Canada. Our main objective was to determine whether the habitat features that influenced nest-site selection also predicted nest success, or whether other factors (e.g. cavity dimensions, clutch initiation date or time of season) were more important. Nest tree decay class, density of suitable cavities and total basal area of large trees were the best predictors of nest-site selection, but these factors were unrelated to nesting success. Estimates of demographic parameters (mean ± SE) included daily nest survival rate (0.988±0.003, years combined), nest success (0.52±0.08), clutch size (5.00±0.14 eggs), female fledglings per successful nest (1.31±0.11), and annual productivity (0.68±0.12 female fledglings per nest per year). Although higher nest survival was associated with both early and late initiated clutches, early-initiated clutches allowed birds to gain the highest annual productivity as early clutches were larger. Nests in deep cavities with small entrances experienced lower predation risk especially during the peak period of nest predation. We concluded that nest-site selection can be predicted by a number of easily measured habitat variables, whereas nest success depended on complicated ecological interactions among nest predators, breeding behaviors, and cavity features. Thus, habitat-based conservation strategies should also consider ecological factors that may not be well predicted by habitat. PMID:23028525

Retinal Vascular Changes and Prospective Risk of Disabling Dementia: the Circulatory Risk in Communities Study (CIRCS)

PubMed Central

Jinnouchi, Hiroshige; Kitamura, Akihiko; Yamagishi, Kazumasa; Kiyama, Masahiko; Imano, Hironori; Okada, Takeo; Cui, Renzhe; Umesawa, Mitsumasa; Muraki, Isao; Hayama-Terada, Mina; Kawasaki, Ryo; Sankai, Tomoko; Ohira, Tetsuya

2017-01-01

Aim: To investigate the association of retinal vascular changes with a risk of dementia in longitudinal population-based study. Methods: We performed a nested case-control study of 3,718 persons, aged 40–89 years, enrolled between 1983 and 2004. Retinal vascular changes were observed in 351 cases with disabling dementia (average period before the onset, 11.2 years) and in 702 controls matched for sex, age, and baseline year. Incidence of disabling dementia was defined as individuals who received cares for disabilities including dementia-related symptoms and/or behavioral disturbance. Conditional logistic regression analysis was used to calculate odds ratio (OR) and multivariable adjusted OR (Models 1 and 2) for incidence of disabling dementia according to each retinal vascular change. Regarding confounding variables, Model 1 included overweight status, hypertension, hyperglycemia, dyslipidemia, and smoking status, whereas Model 2 also included incidence of stroke prior to disabling dementia for further analysis. Results: The proportion of cases (controls) with retinal vascular changes was 23.1 (15.7)% for generalized arteriolar narrowing, 7.7 (7.5)% for focal arteriolar narrowing, 15.7 (11.8)% for arteriovenous nicking, 10.5 (9.3)% for increased arteriolar wall reflex, and 11.4 (9.8)% for any other retinopathy. Generalized arteriolar narrowing was associated with an increased risk of disabling dementia: crude OR, 1.66 (95% confidence interval, 1.19–2.31); Model 1: OR, 1.58 (1.12–2.23); Model 2: OR, 1.48 (1.04–2.10). The number of retinal abnormalities was associated in a dose–response manner with the risk. Conclusion: Generalized arteriolar narrowing and total number of retinal abnormalities may be useful markers for identifying persons at higher risks of disabling dementia. PMID:27904027

Social support and ovarian cancer incidence - A Swedish prospective population-based study.

PubMed

Idahl, Annika; Hermansson, Andrea; Lalos, Ann

2018-05-01

Low social support is associated with worse prognosis for epithelial ovarian cancer (EOC) patients. However, few studies have explored the relation between low social support and incidence of EOC. The aim of this prospective nested case-control study was to examine whether self-perceived low social support was associated with the incidence of EOC. The Swedish Cancer Registry was used to identify participants in the Västerbotten Intervention Programme (VIP) comprising 58,000 women, who later developed EOC. Each case was matched to four cancer free controls. The VIP uses the Social Support questionnaire, a modified version of the validated questionnaire "The Interview Schedule for Social Interaction" (ISSI) measuring quantitative (AVSI) and qualitative (AVAT) aspects of social support. The risk of EOC in relation to AVSI and AVAT was similar between the 239 cases and the 941 controls after adjustment for educational level, smoking, BMI, Cambridge Physical Activity Index and age (aOR 0.85, 95% CI 0.72-1.01 and aOR 0.54, 95% CI 0.16-1.81). Lagtime was found to have no impact. A decreased risk of serous ovarian cancer was seen in women with fewer persons available for informal socializing (aOR 0.75, 95% CI 0.59-0.95). Adjusted analyses showed non-significant odds ratios below 1.0 in the vast majority of histotypes. A general trend towards a decreased risk of ovarian cancer associated with low AVSI and AVAT was identified. Solely the serous subtype was significantly associated with low scores of AVSI. Prospective pathophysiological and epidemiological studies regarding social support are needed. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Antipsychotic treatment and the risk of hip fracture in subjects with schizophrenia: a 10-year population-based case-control study.

PubMed

Wu, Chi-Shin; Chang, Chia-Ming; Tsai, Yu-Ting; Huang, Ya-Wen; Tsai, Hui-Ju

2015-09-01

To investigate the association between antipsychotic treatment and risk of hip fracture in subjects with schizophrenia. Among patients with schizophrenia (ICD-9-CM code 295), 605 cases with hip fracture and 2,828 matched controls were identified from 2002 to 2011 using the National Health Insurance Research Database in Taiwan. The authors conducted a nested case-control study to investigate the association between antipsychotic treatment and risk of hip fracture in subjects with schizophrenia. The modifiable effects of age and gender were evaluated by stratified analysis. In addition, the effects of antipsychotic use, antipsychotic classes, and receptor-binding profiles of antipsychotics, individually, on hip fracture were estimated, and potential confounding factors were adjusted in subsequent analysis. Conditional logistic regressions were applied to determine the effect of antipsychotic treatment on hip fracture. Current antipsychotic use was associated with an increased risk for hip fracture (adjusted odds ratio [AOR] = 1.61; 95% CI, 1.24-2.10). Among current users, new users had a higher risk of hip fracture (AOR = 4.28; 95% CI, 1.76-10.36) than past users (AOR = 1.11; 95% CI, 0.79-1.56). In addition, a significant increased risk of hip fracture was noted in schizophrenia subjects with first-generation antipsychotic use (AOR = 1.59; 95%CI, 1.15-2.20) but not in those with second-generation antipsychotic use (AOR = 1.16; 95% CI, 0.91-1.48). These results extend previous findings and demonstrate an increased risk of hip fracture associated with antipsychotic use in schizophrenia subjects. Further investigation is needed to dissect the underlying mechanisms related to the effect of antipsychotic use on hip fracture in subjects at risk. © Copyright 2015 Physicians Postgraduate Press, Inc.

Population ecology of breeding Pacific common eiders on the Yukon-Kuskokwim Delta, Alaska

USGS Publications Warehouse

Wilson, Heather M.; Flint, Paul L.; Powell, Abby N.; Grand, J. Barry; Moral, Christine L.

2012-01-01

Populations of Pacific common eiders (Somateria mollissima v-nigrum) on the Yukon-Kuskokwim Delta (YKD) in western Alaska declined by 50–90% from 1957 to 1992 and then stabilized at reduced numbers from the early 1990s to the present. We investigated the underlying processes affecting their population dynamics by collection and analysis of demographic data from Pacific common eiders at 3 sites on the YKD (1991–2004) for 29 site-years. We examined variation in components of reproduction, tested hypotheses about the influence of specific ecological factors on life-history variables, and investigated their relative contributions to local population dynamics. Reproductive output was low and variable, both within and among individuals, whereas apparent survival of adult females was high and relatively invariant (0.89 ± 0.005). All reproductive parameters varied across study sites and years. Clutch initiation dates ranged from 4 May to 28 June, with peak (modal) initiation occurring on 26 May. Females at an island study site consistently initiated clutches 3–5 days earlier in each year than those on 2 mainland sites. Population variance in nest initiation date was negatively related to the peak, suggesting increased synchrony in years of delayed initiation. On average, total clutch size (laid) ranged from 4.8 to 6.6 eggs, and declined with date of nest initiation. After accounting for partial predation and non-viability of eggs, average clutch size at hatch ranged from 2.0 to 5.8 eggs. Within seasons, daily survival probability (DSP) of nests was lowest during egg-laying and late-initiation dates. Estimated nest survival varied considerably across sites and years (mean = 0.55, range: 0.06–0.92), but process variance in nest survival was relatively low (0.02, CI: 0.01–0.05), indicating that most variance was likely attributed to sampling error. We found evidence that observer effects may have reduced overall nest survival by 0.0–0.36 across site-years. Study sites with lower sample sizes and more frequent visitations appeared to experience greater observer effects. In general, Pacific common eiders exhibited high spatio-temporal variance in reproductive components. Larger clutch sizes and high nest survival at early initiation dates suggested directional selection favoring early nesting. However, stochastic environmental effects may have precluded response to this apparent selection pressure. Our results suggest that females breeding early in the season have the greatest reproductive value, as these birds lay the largest clutches and have the highest probability of successfully hatching. We developed stochastic, stage-based, matrix population models that incorporated observed spatio-temporal (process) variance and co-variation in vital rates, and projected the stable stage distribution () and population growth rate (λ). We used perturbation analyses to examine the relative influence of changes in vital rates on λ and variance decomposition to assess the proportion of variation in λ explained by process variation in each vital rate. In addition to matrix-based λ, we estimated λ using capture–recapture approaches, and log-linear regression. We found the stable age distribution for Pacific common eiders was weighted heavily towards experienced adult females (≥4 yr of age), and all calculations of λ indicated that the YKD population was stable to slightly increasing (λmatrix = 1.02, CI: 1.00–1.04); λreverse-capture–recapture = 1.05, CI: 0.99–1.11; λlog-linear = 1.04, CI: 0.98–1.10). Perturbation analyses suggested the population would respond most dramatically to changes in adult female survival (relative influence of adult survival was 1.5 times that of fecundity), whereas retrospective variation in λ was primarily explained by fecundity parameters (60%), particularly duckling survival (42%). Among components of fecundity, sensitivities were highest for duckling survival, suggesti

Management of western coniferous forest habitat for nesting accipiter hawks

Treesearch

Richard T. Reynolds

1983-01-01

Availability of nesting sites can limit accipiter populations. Because accipiters nest in dense forest stands, any alteration that opens these stands is likely to lessen their desirability as nest sites. Tree growth and the associated changes in the vegetative structure of aging nest sites limit the number of years sites will be suitable. Therefore, prospective...

Cerulean warbler reproduction, survival, and models of population decline

Treesearch

David A. Buehler; James J. Giocomo; Jason Jones; Paul B. Hamel; Christopher M. Rogers; Tiffany A. Beachy; Dustin W. Varble; Charles P. Nicholson; Kirk L. Roth; JEnnifer Barg; Raleigh J. Robertson; Joseph R. Robb; Kamal Islam

2008-01-01

We present and compare demographic data for cerulean warblers (Dendroica cerulea) from 5 study sites across the range of the species from 1992 to 2006. We conducted field studies to collect data on daily nest survival, nest success, and young fledged per successful nest, and we used data to estimate fecundity. Daily nest survival, nest success, young...

Levels of beta-microseminoprotein in blood and risk of prostate cancer in multiple populations.

PubMed

Haiman, Christopher A; Stram, Daniel O; Vickers, Andrew J; Wilkens, Lynne R; Braun, Katharina; Valtonen-André, Camilla; Peltola, Mari; Pettersson, Kim; Waters, Kevin M; Marchand, Loic Le; Kolonel, Laurence N; Henderson, Brian E; Lilja, Hans

2013-02-06

A common genetic variant (rs10993994) in the 5' region of the gene encoding β-microseminoprotein (MSP) is associated with circulating levels of MSP and prostate cancer risk. Whether MSP levels are predictive of prostate cancer risk has not been evaluated. We investigated the prospective relationship between circulating plasma levels of MSP and prostate cancer risk in a nested case-control study of 1503 case subjects and 1503 control subjects among black, Latino, Japanese, Native Hawaiian, and white men from the Multiethnic Cohort study. We also examined the ability of MSP to serve as a biomarker for discriminating prostate cancer case subjects from control subjects. All statistical tests are two-sided. In all racial and ethnic groups, men with lower MSP levels were at greater risk of developing prostate cancer (odds ratio = 1.02 per one unit decrease in MSP, P < .001 in the prostate-specific antigen [PSA]-adjusted analysis). Compared with men in the highest decile of MSP, the multivariable PSA-adjusted odds ratio was 3.64 (95% confidence interval = 2.41 to 5.49) for men in the lowest decile. The positive association with lower MSP levels was observed consistently across racial and ethnic populations, by disease stage and Gleason score, for men with both high and low levels of PSA and across all genotype classes of rs10993994. However, we did not detect strong evidence of MSP levels in improving prostate cancer prediction beyond that of PSA. Regardless of race and ethnicity or rs10993994 genotype, men with low blood levels of MSP have increased risk of prostate cancer.

Minute perivascular epithelioid cell (PEC) nests in the abdominal lymph nodes--a putative precursor of PEComa.

PubMed

Nagasaka, Toru; Murakami, Yoshiko; Sasaki, Eiichi; Hosoda, Waki; Nakanishi, Toru; Yatabe, Yasushi

2015-04-01

A perivascular epithelioid cell tumor (PEComa) is a peculiar growth defined as a mesenchymal tumor composed of histologically and immunohistochemically distinct perivascular epithelioid cells (PECs). Because neither normal counterparts nor precursor lesions of PEComa have been identified, we examined minute PEC nests, ranged from 0.8 mm to 10 mm, to investigate the possible origin of the PEComa. We examined a total of 80 677 para-aortic and pelvic lymph nodes that were systematically dissected from 1656 patients for gynecological malignancies. The identified lesions were confirmed immunohistochemically with multiple PEC markers, including smooth muscle actin, HMB45, melan-A, MiTF, ER and PgR. A total of 66 minute PEC nests were found in 21 patients (1.3% of the total population) with an average frequency of 3.1 lesions per patient. In cases of multiple involvement, 11 of 13 nests were located at the same level of multiple lymph node or on continuous levels. The lesions were preferentially distributed at the level of para-aortic and high pelvic lymph nodes. All nests were positive for actin and HMB45, whereas the other markers were positive with varying frequencies. The minute PEC nests may be associated with the possible normal counterpart of PEComas. © 2015 Japanese Society of Pathology and Wiley Publishing Asia Pty Ltd.

Serum levels of nerve growth factor (NGF) in patients with major depression disorder and suicide risk.

PubMed

Wiener, Carolina David; de Mello Ferreira, Sharon; Pedrotti Moreira, Fernanda; Bittencourt, Guilherme; de Oliveira, Jacqueline Flores; Lopez Molina, Mariane; Jansen, Karen; de Mattos Souza, Luciano Dias; Rizzato Lara, Diogo; Portela, Luiz Valmor; da Silva, Ricardo Azevedo; Oses, Jean Pierre

2015-09-15

Nerve growth factor (NGF) is an important member of the neurotrophins group and their involvement in the pathophysiology of major depression disorder (MDD) and suicide risk (SR) has been recently suggested. The aim of this study is to evaluate the changes in NGF serum levels in individuals with MDD and with or without risk of suicide, in subjects from a young population-based sample. This is a paired cross-sectional study nested in a population-based study. Individuals were rated for MDD and SR by a diagnostic interview--Mini International Neuropsychiatric Interview (M.I.N.I). The total population of the sample was comprised of 141 subjects distributed in three groups: 47 healthy controls, 47 subjects with current depressive episode without SR (MDD) and 47 subjects with current depressive episode and with SR (MDD + SR). NGF serum levels were significantly reduced in the MDD and MDD + SR groups when compared with controls (p ≤ 0.001). However, there were no differences in NGF levels between the MDD and MDD + SR groups (p = 1.000). These results suggest that reduced NGF serum levels can be a possible biomarker of MDD. Copyright © 2015 Elsevier B.V. All rights reserved.

Raptor nest-site use in relation to the proximity of coalbed methane development

USGS Publications Warehouse

Carlile, J.D.; Sanders, Lindsey E.; Chalfoun, Anna D.; Gerow, K.G.

2018-01-01

Raptor nest–site use in relation to the proximity of coalbed–methane development. Energy development such as coalbed–methane (CBM) extraction is a major land use with largely unknown consequences for many animal species. Some raptor species may be especially vulnerable to habitat changes due to energy development given their ecological requirements and population trajectories. Using 12,977 observations of 3,074 nests of 12 raptor species across nine years (2003–2011) in the Powder River Basin, Wyoming, USA, we evaluated relationships between raptor nest–site use and CBM development. Our objectives were to determine temporal trends in nest–use rates, and whether nest–site use was related to the proximity of CBM development. Across the study area, nest–use rates varied across species and years in a non–linear fashion. We developed a novel randomization test to assess differences in use between nests at developed and undeveloped sites, while controlling for annual variation in nest–site use. Red–tailed hawks (Buteo jamaicensis), burrowing owls (Athene cunicularia), and long–eared owls (Asio otus) used nests in undeveloped areas more than nests in developed areas (i.e. nests near CBM development). Differences between development groups were equivocal for the remaining nine species; however, we caution that we likely had lower statistical power to detect differences for rarer species. Our findings suggest potential avoidance of nesting in areas near CBM development by some species and reveal that CBM effects may be fairly consistent across distances between 400–2,415 m from wells. Future work should consider habitat preferences and fitness outcomes, and control for other key factors such as local prey availability, raptor densities, and weather.

TargetCOPD: a pragmatic randomised controlled trial of targeted case finding for COPD versus routine practice in primary care: protocol.

PubMed

Jordan, Rachel E; Adab, Peymané; Jowett, Sue; Marsh, Jen L; Riley, Richard D; Enocson, Alexandra; Miller, Martin R; Cooper, Brendan G; Turner, Alice M; Ayres, Jon G; Cheng, Kar Keung; Jolly, Kate; Stockley, Robert A; Greenfield, Sheila; Siebert, Stanley; Daley, Amanda; Fitzmaurice, David A

2014-10-04

Many people with clinically significant chronic obstructive pulmonary disease (COPD) remain undiagnosed worldwide. There are a number of small studies which have examined possible methods of case finding through primary care, but no large RCTs that have adequately assessed the most cost-effective approach. In this study, using a cluster randomised controlled trial (RCT) in 56 general practices in the West Midlands, we plan to investigate the effectiveness and cost-effectiveness of a Targeted approach to case finding for COPD compared with routine practice. Using an individual patient RCT nested in the Targeted arm, we plan also to compare the effectiveness and cost-effectiveness of Active case finding using a postal questionnaire (with supplementary opportunistic questionnaires), and Opportunistic-only case finding during routine surgery consultations.All ever-smoking patients aged 40-79 years, without a current diagnosis of COPD and registered with participating practices will be eligible. Patients in the Targeted arm who report positive respiratory symptoms (chronic cough or phlegm, wheeze or dyspnoea) using a brief questionnaire will be invited for further spirometric assessment to ascertain whether they have COPD or not. Post-bronchodilator spirometry will be conducted to ATS standards using an Easy One spirometer by trained research assistants.The primary outcomes will be new cases of COPD and cost per new case identified, comparing targeted case finding with routine care, and two types of targeted case finding (active versus opportunistic). A multilevel logistic regression model will be used to model the probability of detecting a new case of COPD for each treatment arm, with clustering of patients (by practice and household) accounted for using a multi-level structure.A trial-based analysis will be undertaken using costs and outcomes collected during the trial. Secondary outcomes include the feasibility, efficiency, long-term cost-effectiveness, patient and primary care staff views of each approach. This will be the largest RCT of its kind, and should inform how best to identify undiagnosed patients with COPD in the UK and other similar healthcare systems. Sensitivity analyses will help local policy-makers decide which sub-groups of the population to target first. Current controlled trials ISRCTN14930255.

Mixed-stock analysis reveals the migrations of juvenile hawksbill turtles (Eretmochelys imbricata) in the Caribbean Sea.

PubMed

Bowen, B W; Grant, W S; Hillis-Starr, Z; Shaver, D J; Bjorndal, K A; Bolten, A B; Bass, A L

2007-01-01

Hawksbill turtles (Eretmochelys imbricata) migrate between nesting beaches and feeding habitats that are often associated with tropical reefs, but it is uncertain which nesting colonies supply which feeding habitats. To address this gap in hawksbill biology, we compile previously published and new mitochondrial DNA (mtDNA) haplotype data for 10 nesting colonies (N = 347) in the western Atlantic and compare these profiles to four feeding populations and four previously published feeding samples (N = 626). Nesting colonies differ significantly in mtDNA haplotype frequencies (Phi(ST) = 0.588, P < 0.001), corroborating earlier conclusions of nesting site fidelity and setting the stage for mixed-stock analysis. Feeding aggregations show lower but significant structure (Phi(ST) = 0.089, P < 0.001), indicating that foraging populations are not homogenous across the Caribbean Sea. Bayesian mixed-stock estimates of the origins of juveniles in foraging areas show a highly significant, but shallow, correlation with nesting population size (r = 0.378, P = 0.004), supporting the premise that larger rookeries contribute more juveniles to feeding areas. A significant correlation between the estimated contribution and geographical distance from nesting areas (r = -0.394, P = 0.003) demonstrates the influence of proximity on recruitment to feeding areas. The influence of oceanic currents is illustrated by pelagic stage juveniles stranded in Texas, which are assigned primarily (93%) to the upstream rookery in Yucatan. One juvenile had a haplotype previously identified only in the eastern Atlantic, invoking rare trans-oceanic migrations. The mixed-stock analysis demonstrates that harvests in feeding habitats will impact nesting colonies throughout the region, with the greatest detriment to nearby nesting populations.

Nesting Ecology of Hawksbill Sea Turtles (Eretmochelys imbricata) on Utila, Honduras

NASA Astrophysics Data System (ADS)

Damazo, Lindsey Renee Eggers

The hawksbill sea turtle (Eretmochelys imbricata) has a circumtropical distribution and plays an important role in maintaining the health of coral reefs. Unfortunately, hawksbill populations have been decimated, and estimated numbers in the Caribbean are less than 10% of populations a century ago. The hawksbill is considered Critically Endangered, and researchers are coordinating worldwide efforts to protect this species. One country where we lack knowledge regarding hawksbills is Honduras. This study aimed to increase our understanding of hawksbill nesting ecology in Caribbean Honduras. Characteristics of hawksbill nesting activity and a nesting beach on the island of Utila were elucidated using satellite telemetry, beach profiling, vegetation surveys, beach monitoring, and nest temperature profiles. We affixed satellite transmitters to two nesting hawksbills, and found the turtles migrated to different countries. One turtle traveled 403 km to a bay in Mexico, and the other traveled 181 km to a Marine Protected Area off Belize. This study presents the first description of hawksbill migration routes from Honduras, facilitating protection efforts for turtles that traverse international waters. To investigate nesting beach and turtle characteristics, we conducted beach monitoring during the 2012 nesting season. Nesting turtle carapace sizes were similar to worldwide values, but hatchlings were heavier. To measure nest temperatures, we placed thermocouple data loggers in four nests and four pseudo-nests. Data suggested metabolic heating may be maintaining nest temperatures above the pivotal temperature. However, large temperature fluctuations corresponding to rainfall from Hurricane Ernesto (as determined using a time series cross-correlation analysis) make it difficult to predict sex ratios, and underscore the impact stochastic events can have on nest temperatures. We created topographic and substrate profiles of the beach, and found it was 475 m long, yet hawksbills preferentially nested along 80 m that differed from the remainder of the beach in having higher elevation and extensive forest cover. This is the first study from Honduras to report a regular nesting population of hawksbills as well as characterize a nesting beach for this species. It provides an important foundation for hawksbill research in Honduras, a region where we have insufficient knowledge to adequately protect this critically endangered species.

Nest and soil populations of Trinervitermes spp. with particular reference to T. geminatus (Wasmann), (Isoptera), in Southern Guinea savanna near Mokwa, Nigeria.

PubMed

Ohiagu, C E

1979-01-01

Nest and soil populations of Trinervitermes spp. were estimated on grazed secondary savanna woodland near Mokwa cattle ranch and on primary savanna woodland, 6 km from the ranch. Nest populations were estimated by obtaining a relationship between size of nest and the number of termites in the nest and using the relationship to estimate populations in measured nests within the study area.Mound populations of T. geminatus, by far the most abundant species, were 222 m -2 at a mound density of 232 ha -1 at the ranch, and 225 m -2 at a mound density of 175 ha -1 on primary savanna woodland. The mound population at the ranch represented a fresh weight biomass of 1.089 g m -2 . Changes in abundance of the mound population of T. geminatus were correlated with breeding and foraging cycles. Maximum numbers (388 m -2 , 2.03 g m -2 ) in August/September were reduced by the flight of alates and loss of foragers to predators; thereafter, the population continued to decrease (126 m -2 , 0.57 g m -2 ) until the cessation of foraging in April/May and numbers of larvae and nymphs began to increase. Soil and mound sampling in primary and secondary savanna showed that although T. geminatus is a mound inhabiting species, two thirds of the mound plus soil population was outside the mounds giving a total population of 737 m -2 (3.08 g m -2 ). Alate production was estimated at 15.5 m -2 (0.19 g m -2 ) and neuter production at 367 m -2 (1.66 g m -2 ); production/biomass ratio was 1.0 T. togoensis (total population of 21 m -2 ) and T. occidentalis (200 m -2 ) had 90-96% of the total numbers outside the mounds, indicating that these two species were primarily subterranean.

Predictors and outcomes of superior mesenteric artery syndrome in patients with constipation: a prospective, nested case-control study.

PubMed

Xu, Lin; Yu, Wen-Kui; Lin, Zhi-Liang; Jiang, Jun; Feng, Xiao-Bo; Li, Ning

2014-10-01

Superior mesenteric artery (SMA) syndrome may occur in patients with constipation, whereas the association between these two distinct diseases has not been confirmed yet. We investigated the incidence, risk factors and treatment strategy associated with SMA syndrome in constipated patients. We conducted a prospective nested case-control study from a 9-year hospitalization cohort (n=973). Cases were matched to controls 1:4 on factors of age and gender. Cases developed SMA syndrome in long term follow-up (n=26) and controls did not (n=104). Independent risk factors were identified by using univariate analysis and conditional logistic regression analysis. Enteral nutritional support was applied in all cases and its curative effect was evaluated by retrospective analysis. The incidence of SMA syndrome was 2.67%. The risk factors under scrutiny were body mass index (BMI)≤18 (odds ratio (OR) 2.89, 95% CI 1.14 to 9.31) and abnormal colon transit time (OR 3.57, 95% CI 1.36 to 9.35). Twenty-two patients recovered after treatment of nutritional support, and the success rate of conservative treatment was 84.6%. BMI≤18 and prolonged colon transit time both were risk factors associated with SMA syndrome in constipated patients. Enteral nutritional support should be adopted as the first-line treatment for this condition.

Indirect cannibalism by crèche-aged American White Pelican (Pelecanus erythrorhynchos) chicks

USGS Publications Warehouse

Bartos, Alisa J.; Sovada, Marsha A.; Igl, Lawrence D.; Pietz, Pamela J.

2013-01-01

At nesting colonies of American White Pelicans (Pelecanus erythrorhynchos), many chicks die from siblicide, severe weather, and disease; this results in carcasses available for scavenging by conspecifics (i.e., indirect cannibalism). Indirect cannibalism has not been reported previously for this species. We describe five cases of crèche-aged American White Pelican chicks consuming or attempting to consume dead younger chicks at two nesting colonies in the northern plains of North America. Cannibalism in the American White Pelican appears to be rare and likely plays no role in the species’ population ecology or dynamics; however, it might be an important survival strategy of individual chicks when food resources are limited.

Use of radio-tagging to map spatial organization and social interactions in insects.

PubMed

Moreau, Mathieu; Arrufat, Patrick; Latil, Gérard; Jeanson, Raphaël

2011-01-01

Understanding of the organization of animal societies often requires knowledge of the identity of group members and their spatial location. We propose an original experimental design to track automatically the position of individuals using radio frequency identification technology (RFID). Ants equipped with passive transponders were detected by a reader mounted on a mobile arm moving across the nest surface. We developed an algorithm to accurately extract the positions of individuals moving in two dimensions. Our method was validated on synthetic test cases and then used for characterization of the spatial distribution of ants within nests. This approach provides an amenable system for monitoring large populations of individuals over long periods of time.

Birth outcomes of cases with conotruncal defects of heart - a population-based case-control study.

PubMed

Vereczkey, Attila; Kósa, Zsolt; Csáky-Szunyogh, Melinda; Gerencsér, Balázs; Czeizel, Andrew E

2015-03-01

The aim of this study was to evaluate the birth outcomes of cases with four types of conotruncal defects (CTDs), i.e. common truncus, transposition of great arteries, tetralogy of Fallot and double-outlet right ventricle. Birth outcomes of 597 live-born cases with CTD and 38,151 population controls without any defects were compared in the population-based large dataset of the Hungarian Case-Control Surveillance of Congenital Abnormalities completed by socio-demographic variables of their mothers. There was a male excess in cases with CTD (56.8%) with the same mean gestational age (39.4 versus 39.4 weeks) and preterm birth rate (8.2 versus 9.2%), but their mean birth weight was smaller (3077 versus 3276 g) with a high rate of low birthweight (14.6 versus 5.7%) compared to the birth outcomes of population controls. These data indicate intrauterine growth restriction of fetuses affected with transposition of great arteries, tetralogy of Fallot and double-outlet right ventricle particularly in females, while there were a shorter mean gestational age and smaller mean birth weigh in cases with common truncus. In general CTD, except common truncus, had no effect for gestational age but associated with a high risk for intrauterine fetal growth restriction particularly in female cases.

Using Field Data and GIS-Derived Variables to Model Occurrence of Williamson's Sapsucker Nesting Habitat at Multiple Spatial Scales.

PubMed

Drever, Mark C; Gyug, Les W; Nielsen, Jennifer; Stuart-Smith, A Kari; Ohanjanian, I Penny; Martin, Kathy

2015-01-01

Williamson's sapsucker (Sphyrapicus thyroideus) is a migratory woodpecker that breeds in mixed coniferous forests in western North America. In Canada, the range of this woodpecker is restricted to three small populations in southern British Columbia, precipitating a national listing as 'Endangered' in 2005, and the need to characterize critical habitat for its survival and recovery. We compared habitat attributes between Williamson's sapsucker nest territories and random points without nests or detections of this sapsucker as part of a resource selection analysis to identify the habitat features that best explain the probability of nest occurrence in two separate geographic regions in British Columbia. We compared the relative explanatory power of generalized linear models based on field-derived and Geographic Information System (GIS) data within both a 225 m and 800 m radius of a nest or random point. The model based on field-derived variables explained the most variation in nest occurrence in the Okanagan-East Kootenay Region, whereas nest occurrence was best explained by GIS information at the 800 m scale in the Western Region. Probability of nest occurrence was strongly tied to densities of potential nest trees, which included open forests with very large (diameter at breast height, DBH, ≥57.5 cm) western larch (Larix occidentalis) trees in the Okanagan-East Kootenay Region, and very large ponderosa pine (Pinus ponderosa) and large (DBH 17.5-57.5 cm) trembling aspen (Populus tremuloides) trees in the Western Region. Our results have the potential to guide identification and protection of critical habitat as required by the Species at Risk Act in Canada, and to better manage Williamson's sapsucker habitat overall in North America. In particular, management should focus on the maintenance and recruitment of very large western larch and ponderosa pine trees.

From endogenous to exogenous pattern formation: Invasive plant species changes the spatial distribution of a native ant.

PubMed

Li, Kevin; He, Yifan; Campbell, Susanna K; Colborn, A Shawn; Jackson, Eliot L; Martin, Austin; Monagan, Ivan V; Ong, Theresa Wei Ying; Perfecto, Ivette

2017-06-01

Invasive species are a significant threat to global biodiversity, but our understanding of how invasive species impact native communities across space and time remains limited. Based on observations in an old field in Southeast Michigan spanning 35 years, our study documents significant impacts of habitat change, likely driven by the invasion of the shrub, Elaeagnus umbellata, on the nest distribution patterns and population demographics of a native ant species, Formica obscuripes. Landcover change in aerial photographs indicates that E. umbellata expanded aggressively, transforming a large proportion of the original open field into dense shrubland. By comparing the ant's landcover preferences before and after the invasion, we demonstrate that this species experienced a significant unfavorable change in its foraging areas. We also find that shrub landcover significantly moderates aggression between nests, suggesting nests are more related where there is more E. umbellata. This may represent a shift in reproductive strategy from queen flights, reported in the past, to asexual nest budding. Our results suggest that E. umbellata may affect the spatial distribution of F. obscuripes by shifting the drivers of nest pattern formation from an endogenous process (queen flights), which led to a uniform pattern, to a process that is both endogenous (nest budding) and exogenous (loss of preferred habitat), resulting in a significantly different clustered pattern. The number and sizes of F. obscuripes nests in our study site are projected to decrease in the next 40 years, although further study of this population's colony structures is needed to understand the extent of this decrease. Elaeagnus umbellata is a common invasive shrub, and similar impacts on native species might occur in its invasive range, or in areas with similar shrub invasions. © 2017 John Wiley & Sons Ltd.

Active commuting reduces the risk of wrist fractures in middle-aged women-the UFO study.

PubMed

Englund, U; Nordström, P; Nilsson, J; Hallmans, G; Svensson, O; Bergström, U; Pettersson-Kymmer, U

2013-02-01

Middle-aged women with active commuting had significantly lower risk for wrist fracture than women commuting by car/bus. Our purpose was to investigate whether a physically active lifestyle in middle-aged women was associated with a reduced risk of later sustaining a low-trauma wrist fracture. The Umeå Fracture and Osteoporosis (UFO) study is a population-based nested case-control study investigating associations between lifestyle and fragility fractures. From a cohort of ~35,000 subjects, we identified 376 female wrist fracture cases who had reported data regarding their commuting habits, occupational, and leisure physical activity, before they sustained their fracture. Each fracture case was compared with at least one control drawn from the same cohort and matched for age and week of reporting data, yielding a total of 778 subjects. Mean age at baseline was 54.3 ± 5.8 years, and mean age at fracture was 60.3 ± 5.8 years. Conditional logistic regression analysis with adjustments for height, body mass index, smoking, and menopausal status showed that subjects with active commuting (especially walking) were at significantly lower risk of sustaining a wrist fracture (OR 0.48; 95 % CI 0.27-0.88) compared with those who commuted by car or bus. Leisure time activities such as dancing and snow shoveling were also associated with a lower fracture risk, whereas occupational activity, training, and leisure walking or cycling were unrelated to fracture risk. This study suggests that active commuting is associated with a lower wrist fracture risk, in middle-aged women.

The risk of thromboembolic events in kidney transplant patients.

PubMed

Verhave, Jacobien C; Tagalakis, Vicky; Suissa, Samy; Madore, François; Hébert, Marie-Josée; Cardinal, Héloïse

2014-06-01

Little is known about the risk of venous thrombosis following kidney transplant. To determine this we estimated the risk of thromboembolic events (TEs) in a cohort of consecutive patients who underwent kidney transplantation at a single tertiary care center over an 11-year period and calculated standardized incidence ratios (SIRs) for a first TE in kidney transplant recipients compared with the general population. We then performed a nested case-control study and compared patients with and without TEs to identify risk factors for thrombosis. Among 913 kidney transplant recipients (KTRs), 68 patients developed these events. The SIR for TEs in KTRs compared with the general population was 7.9 over the duration of follow-up. The risk was particularly higher in the first post-transplant year (SIR 26.1) but remained elevated afterward (SIR 5.2). Hospitalization, use of sirolimus, low hemoglobin level, and use of renin-angiotensin system inhibitors were independently associated with these events. When cases of TEs that occurred during hospitalization were excluded, the risk of these events remained elevated. The risk of TEs in KTRs was eightfold higher than in the general population but not fully explained by the increased risk associated with hospitalization. Our results underscore the important risk of thrombosis in patients who received a kidney transplant, making vigilance mandatory especially during hospitalization.

Factors influencing nesting success of king eiders on northern Alaska's Coastal Plain

USGS Publications Warehouse

Bentzen, R.L.; Powell, A.N.; Suydam, R.S.

2008-01-01

King eider (Somateria spectabilis) populations have declined markedly in recent decades for unknown reasons. Nest survival is one component of recruitment, and a female's chance of reproductive success increases with her ability to choose an appropriate nesting strategy. We estimated variation in daily nest survival of king eiders at 2 sites, Teshekpuk and Kuparuk, Alaska, USA, 2002-2005. We evaluated both a priori and exploratory competing models of nest survival that considered importance of nest concealment, seclusion, and incubation constancy as strategies to avoid 2 primary egg predators, avian (Larus spp., Stercorarius spp., and Corvus corax) and fox (Alopex lagopus). We used generalized nonlinear techniques to examine factors affecting nest survival rates and information-theoretic approaches to select among competing models. Estimated nest survival, accounting for a nest visitation effect, varied considerably across sites and years (0.21-0.57); however, given our small sample size, much of this variation maybe attributable to sampling variation (??process = 0.007, 95% CI: 0.003-0.070). Nest survival was higher at Kuparuk than Teshekpuk in all years; however, due to the correlative nature of our data, we cannot determine the underlying causes with any certainty. We found mixed support for the concealed breeding strategy, females derived no benefit from nesting in areas with more willow (Salix spp.; measure of concealment) except that the observer effect diminished as willow cover increased. We suggest these patterns are due to conflicting predation pressures. Nest survival was not higher on islands (measure of seclusion) or with increased incubation constancy but was higher post-fox removal, indicating that predator control on breeding grounds could be a viable management option. Nest survival was negatively affected by our nest visitations, most likely by exposing the nest to avian scavengers. We recommend precautions be taken to limit the effects of nest visits in future studies and to consider them as a possible negative bias in estimated nest survival. Future models of the impacts of development within the breeding grounds of king eider should consider the influence of humans in the vicinity of nests.

Evidence of territoriality and species interactions from spatial point-pattern analyses of subarctic-nesting geese

USGS Publications Warehouse

Reiter, Matthew E.; Andersen, David E.

2013-01-01

Quantifying spatial patterns of bird nests and nest fate provides insights into processes influencing a species’ distribution. At Cape Churchill, Manitoba, Canada, recent declines in breeding Eastern Prairie Population Canada geese (Branta canadensis interior) has coincided with increasing populations of nesting lesser snow geese (Chen caerulescens caerulescens) and Ross’s geese (Chen rossii). We conducted a spatial analysis of point patterns using Canada goose nest locations and nest fate, and lesser snow goose nest locations at two study areas in northern Manitoba with different densities and temporal durations of sympatric nesting Canada and lesser snow geese. Specifically, we assessed (1) whether Canada geese exhibited territoriality and at what scale and nest density; and (2) whether spatial patterns of Canada goose nest fate were associated with the density of nesting lesser snow geese as predicted by the protective-association hypothesis. Between 2001 and 2007, our data suggest that Canada geese were territorial at the scale of nearest neighbors, but were aggregated when considering overall density of conspecifics at slightly broader spatial scales. The spatial distribution of nest fates indicated that lesser snow goose nest proximity and density likely influence Canada goose nest fate. Our analyses of spatial point patterns suggested that continued changes in the distribution and abundance of breeding lesser snow geese on the Hudson Bay Lowlands may have impacts on the reproductive performance of Canada geese, and subsequently the spatial distribution of Canada goose nests.

Association of DD genotype of angiotensin-converting enzyme gene (I/D) polymorphism with hypertension among a North Indian population.

PubMed

Rana, Garima; Yadav, Suniti; Joshi, Shipra; Saraswathy, K N

2018-01-01

Hypertension, a major risk factor for cardiovascular diseases, is among the leading causes of morbidity and mortality worldwide. Genetic predisposition to the risk of developing hypertension due to angiotensin-converting enzyme (ACE) gene insertion(I)/deletion(D) polymorphism (through altered serum ACE activity) is well documented among various populations. The present study investigated the possible association between ACE (DD) genotype and hypertension using a nested case-control study design including 451 individuals (of either sex in the age group 30-65 years) from a rural North Indian population practicing agriculture and lacto-vegetarianism. Blood Pressure was classified using JNC-7 criterion. Age- and sex-matched individuals were selected from normotensive (N-122), pre-hypertensive (N-123), hypertensive not on medication (N-122), and hypertensive on medication (N-84) categories. Amplification of DNA and genotyping of PCR product was done using standard protocols. From the analysis, comparatively higher frequency of individuals with DD genotype in the hypertensive category was observed, indicating a possible relation between DD genotype and hypertension. The odds ratio analysis revealed 2.225 (1.13-4.37)-fold significant increased risk for hypertension among cases, validating the vulnerability of individuals with DD genotype towards hypertension. Thus, the present study highlights the increased risk for developing hypertension due to ACE DD genotype in the studied population.