Egg size matching by an intraspecific brood parasite

USGS Publications Warehouse

Lemons, Patrick R.; Sedinger, James S.

2011-01-01

Avian brood parasitism provides an ideal system with which to understand animal recognition and its affect on fitness. This phenomenon of laying eggs in the nests of other individuals has classically been framed from the perspective of interspecific brood parasitism and host recognition of parasitic eggs. Few examples exist of strategies adopted by intraspecific brood parasites to maximize success of parasitic eggs. Intraspecific brood parasitism within precocial birds can be a risky strategy in that hatch synchrony is essential to reproductive success. Given that egg size is positively correlated with incubation time, parasitic birds would benefit by recognizing and selecting hosts with a similar egg size. Intraspecific brood parasitism is an alternative reproductive strategy in black brant (Branta bernicla nigricans), a colonial nesting goose with precocial young. Based on a randomization test, parasitic eggs in this study differed less in size from eggs in their host's nests than did random eggs placed in random nests. Parasitic eggs were remarkably similar in size to hosts’ eggs, differing by <2% of volume on average from host eggs, whereas randomly paired eggs in random nests differed by nearly 8%. The precision with which parasitic brant match the egg size of hosts in our study supports our hypothesis that brant match egg size of hosts, thereby maximizing hatching success of their parasitic eggs.

Methodologic considerations in the design and analysis of nested case-control studies: association between cytokines and postoperative delirium.

PubMed

Ngo, Long H; Inouye, Sharon K; Jones, Richard N; Travison, Thomas G; Libermann, Towia A; Dillon, Simon T; Kuchel, George A; Vasunilashorn, Sarinnapha M; Alsop, David C; Marcantonio, Edward R

2017-06-06

The nested case-control study (NCC) design within a prospective cohort study is used when outcome data are available for all subjects, but the exposure of interest has not been collected, and is difficult or prohibitively expensive to obtain for all subjects. A NCC analysis with good matching procedures yields estimates that are as efficient and unbiased as estimates from the full cohort study. We present methodological considerations in a matched NCC design and analysis, which include the choice of match algorithms, analysis methods to evaluate the association of exposures of interest with outcomes, and consideration of overmatching. Matched, NCC design within a longitudinal observational prospective cohort study in the setting of two academic hospitals. Study participants are patients aged over 70 years who underwent scheduled major non-cardiac surgery. The primary outcome was postoperative delirium from in-hospital interviews and medical record review. The main exposure was IL-6 concentration (pg/ml) from blood sampled at three time points before delirium occurred. We used nonparametric signed ranked test to test for the median of the paired differences. We used conditional logistic regression to model the risk of IL-6 on delirium incidence. Simulation was used to generate a sample of cohort data on which unconditional multivariable logistic regression was used, and the results were compared to those of the conditional logistic regression. Partial R-square was used to assess the level of overmatching. We found that the optimal match algorithm yielded more matched pairs than the greedy algorithm. The choice of analytic strategy-whether to consider measured cytokine levels as the predictor or outcome-- yielded inferences that have different clinical interpretations but similar levels of statistical significance. Estimation results from NCC design using conditional logistic regression, and from simulated cohort design using unconditional logistic regression, were similar. We found minimal evidence for overmatching. Using a matched NCC approach introduces methodological challenges into the study design and data analysis. Nonetheless, with careful selection of the match algorithm, match factors, and analysis methods, this design is cost effective and, for our study, yields estimates that are similar to those from a prospective cohort study design.

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.

Nest covering in plovers: How modifying the visual environment influences egg camouflage.

PubMed

Troscianko, Jolyon; Wilson-Aggarwal, Jared; Spottiswoode, Claire N; Stevens, Martin

2016-10-01

Camouflage is one of the most widespread antipredator defences, and its mechanistic basis has attracted considerable interest in recent years. The effectiveness of camouflage depends on the interaction between an animal's appearance and its background. Concealment can therefore be improved by changes to an animal's own appearance, by behaviorally selecting an optimal background, or by modifying the background to better match the animal's own appearance. Research to date has largely focussed on the first of these mechanisms, whereas there has been little work on the second and almost none on the third. Even though a number of animal species may potentially modify their environment to improve individual-specific camouflage, this has rarely if ever been quantitatively investigated, or its adaptive value tested. Kittlitz's plovers (Charadrius pecuarius) use material (stones and vegetation) to cover their nests when predators approach, providing concealment that is independent of the inflexible appearance of the adult or eggs, and that can be adjusted to suit the local surrounding background. We used digital imaging and predator vision modeling to investigate the camouflage properties of covered nests, and whether their camouflage affected their survival. The plovers' nest-covering materials were consistent with a trade-off between selecting materials that matched the color of the eggs, while resulting in poorer nest pattern and contrast matching to the nest surroundings. Alternatively, the systematic use of materials with high-contrast and small-pattern grain sizes could reflect a deliberate disruptive coloration strategy, whereby high-contrast material breaks up the telltale outline of the clutch. No camouflage variables predicted nest survival. Our study highlights the potential for camouflage to be enhanced by background modification. This provides a flexible system for modifying an animal's conspicuousness, to which the main limitation may be the available materials rather than the animal's appearance.

Tumor necrosis factor-α inhibitor treatment and the risk of incident cardiovascular events in patients with early rheumatoid arthritis: a nested case-control study.

PubMed

Desai, Rishi J; Rao, Jaya K; Hansen, Richard A; Fang, Gang; Maciejewski, Matthew; Farley, Joel

2014-11-01

To compare the risk of cardiovascular (CV) events between use of tumor necrosis factor-α inhibitors (TNFi) and nonbiologic disease-modifying antirheumatic drugs (DMARD) in patients with early rheumatoid arthritis (RA). A nested case-control study was conducted using data from Truven's MarketScan commercial and Medicare claims database for patients with early RA who started treatment with either a TNFi or a nonbiologic DMARD between January 1, 2008, and December 31, 2010. Date of CV event diagnosis for cases was defined as the event date, and 12 age-matched and sex-matched controls were sampled using incidence density sampling. Drug exposure was defined into the following mutually exclusive categories hierarchically: (1) current use of TNFi (with or without nonbiologics), (2) past use of TNFi (with or without nonbiologics), (3) current use of nonbiologics only, and (4) past use of nonbiologics only. Current use was defined as any use in the period 90 days prior to the event date. Conditional logistic regression models were used to derive incidence rate ratios (IRR). From the cohort of patients with early RA, 279 cases of incident CV events and 3348 matched controls were identified. The adjusted risk of CV events was not significantly different between current TNFi users and current nonbiologic users (IRR 0.92, 95% CI 0.59-1.44). However, past users of nonbiologics showed significantly higher risk compared to current nonbiologic users (IRR 1.47, 95% CI 1.04-2.08). No differences in the CV risk were found between current TNFi and current nonbiologic DMARD treatment in patients with early RA.

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.

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).

Association between Use of Exogenous Testosterone Therapy and Risk of Venous Thrombotic Events among Exogenous Testosterone Treated and Untreated Men with Hypogonadism.

PubMed

Li, Hu; Benoit, Karin; Wang, Wei; Motsko, Stephen

2016-04-01

Limited information exists about whether exogenous testosterone therapy is associated with a risk of venous thrombotic events. We investigated via cohort and nested case-control analyses whether exogenous testosterone therapy is associated with the risk of venous thrombotic events in men with hypogonadism. Databases were reviewed to identify men prescribed exogenous testosterone therapy and/or men with a hypogonadism diagnosis. Propensity score 1:1 matching was used to select patients for cohort analysis. Cases (men with venous thrombotic events) were matched 1:4 with controls (men without venous thrombotic events) for the nested case-control analysis. Primary outcome was defined as incident idiopathic venous thrombotic events. Cox regression and conditional logistic regression were used to assess HRs and ORs, respectively. Sensitivity analyses were also performed. A total of 102,650 exogenous testosterone treated and 102,650 untreated patients were included in cohort analysis after matching, and 2,785 cases and 11,119 controls were included in case-control analysis. Cohort analysis revealed a HR of 1.08 for all testosterone treated patients (95% CI 0.91, 1.27, p = 0.378). Case-control analysis resulted in an OR of 1.02 (95% CI 0.92, 1.13, p = 0.702) for current exogenous testosterone therapy exposure and an OR of 0.92 (95% CI 0.82, 1.03, p = 0.145) for past exogenous testosterone therapy exposure. These results remained nonstatistically significant after stratifying by exogenous testosterone therapy administration route and age category. Most sensitivity analyses yielded consistent results. No significant association was found between exogenous testosterone therapy and incidents of idiopathic or overall venous thrombotic events in men with hypogonadism. However, some discrepant findings exist for the association between injectable formulations and the risk of overall venous thrombotic events. Copyright © 2016 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

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.

3D deformable image matching: a hierarchical approach over nested subspaces

NASA Astrophysics Data System (ADS)

Musse, Olivier; Heitz, Fabrice; Armspach, Jean-Paul

2000-06-01

This paper presents a fast hierarchical method to perform dense deformable inter-subject matching of 3D MR Images of the brain. To recover the complex morphological variations in neuroanatomy, a hierarchy of 3D deformations fields is estimated, by minimizing a global energy function over a sequence of nested subspaces. The nested subspaces, generated from a single scaling function, consist of deformation fields constrained at different scales. The highly non linear energy function, describing the interactions between the target and the source images, is minimized using a coarse-to-fine continuation strategy over this hierarchy. The resulting deformable matching method shows low sensitivity to local minima and is able to track large non-linear deformations, with moderate computational load. The performances of the approach are assessed both on simulated 3D transformations and on a real data base of 3D brain MR Images from different individuals. The method has shown efficient in putting into correspondence the principle anatomical structures of the brain. An application to atlas-based MRI segmentation, by transporting a labeled segmentation map on patient data, is also presented.

Drought-caused delay in nesting of Sonoran Desert birds and its facilitation of parasite- and predator-mediated variation in reproductive success

USGS Publications Warehouse

McCreedy, Chris; van Riper, Charles

2015-01-01

As our understanding of climate change has increased, so has our awareness of the impacts of these changes on biotic systems. Climate models are nearly unanimous in their predictions for increased drought frequency in southwestern North America, and delays in nest initiation due to drought may influence nesting success and productivity for many Sonoran Desert bird species. In southeastern California and western Arizona in 2004–2009, we found negative correlations for 13 of 13 species between nest initiation date and rainfall accumulation during the preceding 4-month winter rainy season. Nesting was delayed more than 3 weeks for some species during extreme droughts in 2006 and 2007. During 2004–2009, we found a significant negative effect of nest initiation date on nest survival probability (β̂ = −0.031 ± 0.005 SE, P < 0.001) for the four species of greatest sample size. To investigate the role of nesting delay in nesting success and productivity, in 2010 we conducted a manipulative experiment with Black-tailed Gnatcatchers (Polioptila melanura; BTGN) and Verdins (Auriparus flaviceps; VERD). Following a wet winter, we delayed clutch initiation dates for treatment pairs to match first-egg dates that we observed during droughts in 2006 and 2007. Nest initiation date had a significant negative effect on nest survival of both species (BTGN: β̂ = −1.18 ± 0.27 SE, P < 0.001; VERD: β̂ = −2.33 ± 0.51 SE, P = 0.003). Treatment pairs were unable to overcome the lost period of high productivity in March and early April, and had lower productivity than control pairs over the entire breeding season. As nest predation and Brown-headed Cowbird (Molothrus ater) parasitism were the most common causes of nest failure, we conclude that the impacts of climate change–caused drought on annual reproductive output in the Sonoran Desert will be further compounded by parasitism and predation for Black-tailed Gnatcatchers and by predation for Verdins.

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.

Pituitary Antibodies in Women with Hashimoto's Thyroiditis: Prevalence in Diagnostic and Prediagnostic Sera

PubMed Central

Guaraldi, Federica; Landek-Salgado, Melissa A.; Hutfless, Susan; Samoni, Francesca; Talor, Monica V.; Matos, Peter G.; Salvatori, Roberto; Rose, Noel R.

2012-01-01

Background Pituitary antibodies have been reported with greater frequency in patients with Hashimoto's thyroiditis than in healthy controls, although there is significant variability in the strength of the association and the methodologies used. Methods We designed a nested case–control study to characterize the prevalence of pituitary antibodies at the time of the clinical diagnosis of Hashimoto's thyroiditis, as well as at 2, 5, and 7 years before diagnosis. Active component female service member cases (n=87) and matched female controls (n=107) were selected using the Defense Medical Surveillance System database (DMSSD) between January 1998 and December 2007. Pituitary antibodies were measured by immunofluorescence using human pituitary glands collected at autopsy as the substrate. Results At diagnosis, pituitary antibodies were present in 9% of cases with Hashimoto's (8 of 87) and 3% of controls (3 of 107). When the data were analyzed using a conditional logistic regression model, which takes into account the matching on age and work status, pituitary antibodies increased the odds of having Hashimoto's thyroiditis by sevenfold (95% confidence interval from 1.3 to 40.1, p=0.028), after adjusting for components of the DMSSD-category-termed race and for thyroperoxidase antibodies. Before diagnosis, pituitary antibodies were positive in 3 of the 11 subjects (2 cases and 1 control) at the −2-year time point, and negative in all 11 subjects at the −5- and −7-year time points. Conclusions In summary, using a nested case–control design, we confirm that pituitary antibodies are more common in Hashimoto's thyroiditis and suggest that they appear late during its natural history. PMID:22468943

Beta-blocker usage after malignant melanoma diagnosis and survival: a population-based nested case-control study.

PubMed

McCourt, C; Coleman, H G; Murray, L J; Cantwell, M M; Dolan, O; Powe, D G; Cardwell, C R

2014-04-01

Beta-blockers have potential antiangiogenic and antimigratory activity. Studies have demonstrated a survival benefit in patients with malignant melanoma treated with beta-blockers. To investigate the association between postdiagnostic beta-blocker usage and risk of melanoma-specific mortality in a population-based cohort of patients with malignant melanoma. Patients with incident malignant melanoma diagnosed between 1998 and 2010 were identified within the U.K. Clinical Practice Research Datalink and confirmed using cancer registry data. Patients with malignant melanoma with a melanoma-specific death (cases) recorded by the Office of National Statistics were matched on year of diagnosis, age and sex to four malignant melanoma controls (who lived at least as long after diagnosis as their matched case). A nested case-control approach was used to investigate the association between postdiagnostic beta-blocker usage and melanoma-specific death and all-cause mortality. Conditional logistic regression was applied to generate odds ratios (ORs) and 95% confidence intervals (CIs) for beta-blocker use determined from general practitioner prescribing. Beta-blocker medications were prescribed after malignant melanoma diagnosis to 20·2% of 242 patients who died from malignant melanoma (cases) and 20·3% of 886 matched controls. Consequently, there was no association between beta-blocker use postdiagnosis and cancer-specific death (OR 0·99, 95% CI 0·68-1·42), which did not markedly alter after adjustment for confounders including stage (OR 0·87, 95% CI 0·56-1·34). No significant associations were detected for individual beta-blocker types, by defined daily doses of use or for all-cause mortality. Contrary to some previous studies, beta-blocker use after malignant melanoma diagnosis was not associated with reduced risk of death from melanoma in this U.K. population-based study. © 2014 British Association of Dermatologists.

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.

The obesity paradox in stable chronic heart failure does not persist after matching for indicators of disease severity and confounders.

PubMed

Frankenstein, Lutz; Zugck, Christian; Nelles, Manfred; Schellberg, Dieter; Katus, Hugo A; Remppis, B Andrew

2009-12-01

To verify whether controlling for indicators of disease severity and confounders represents a solution to the obesity paradox in chronic heart failure (CHF). From a cohort of 1790 patients, we formed 230 nested matched triplets by individually matching patients with body mass index (BMI) > 30 kg/m(2) (Group 3), BMI 20-24.9 k/m(2) (Group 1) and BMI 25-29.9 kg/m(2) (Group 2), according to NT-proBNP, age, sex, and NYHA class (triplet = one matched patient from each group). Although in the pre-matching cohort, BMI group was a significant univariable prognostic indicator, it did not retain significance [heart rate (HR): 0.91, 95% CI: 0.78-1.05, chi(2): 1.67] when controlled for group propensities as covariates. Furthermore, in the matched cohort, 1-year mortality and 3-year mortality did not differ significantly. Here, BMI again failed to reach statistical significance for prognosis, either as a continuous or categorical variable, whether crude or adjusted. This result was confirmed in the patients not selected for matching. NT-proBNP, however, remained statistically significant (log(NT-proBNP): HR: 1.49, 95% CI: 1.13-1.97, chi(2): 7.82) after multivariable adjustment. The obesity paradox does not appear to persist in a matched setting with respect to indicators of disease severity and other confounders. NT-proBNP remains an independent prognostic indicator of adverse outcome irrespective of obesity status.

Actinic keratosis-related signs predictive of squamous cell carcinoma in renal transplant recipients: a nested case-control study.

PubMed

Jiyad, Z; O'Rourke, P; Soyer, H P; Green, A C

2017-04-01

Squamous cell carcinoma (SCC) and intraepidermal carcinoma (IEC) commonly arise in actinically damaged skin. To identify clinical features of actinic change that correlate with an increased risk of SCC or IEC in the short-to-medium term as guidance for prioritizing field treatment. In a nested case-control study, cases were renal transplant recipients who developed an incident SCC or IEC within 18 months following baseline examination and photography. Controls without SCC or IEC were matched to cases on age, sex and duration of immunosuppression. Predefined skin sites on the head, neck and upper limbs were examined using baseline photographs to assess objectively the following features of actinic damage: presence of actinic keratosis (AK) patch (defined as AK > 1 cm 2 ), number of AK patches, number of AKs and area affected by AK. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using McNemar's test to identify differences in SCC/IEC risk combined and SCC risk alone between case and control skin sites. Thirty-nine cases were matched to 39 controls. Significant associations with the presence of an AK patch, number of AK patches, number of AKs and area affected by AKs were identified. The presence of an AK patch conferred an 18-fold increased risk of SCC (OR 18·00, 95% CI 2·84-750) and more than a sixfold increased risk of SCC/IEC combined (OR 6·60, 95% CI 2·56-21·66). AK patches are predictive of SCC/IEC development within 18 months. This can be used to guide site selection for field treatment in patients with widespread actinic damage. © 2016 British Association of Dermatologists.

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.

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.

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.

Exposure to sennoside-digoxin interaction and risk of digoxin toxicity: a population-based nested case-control study.

PubMed

Wang, Meng-Ting; Li, I-Hsun; Lee, Wan-Ju; Huang, Tien-Yu; Leu, Hsin-Bang; Chan, Agnes L F

2011-11-01

Digoxin is an important medication for heart failure (HF) patients and sennosides are widely used to treat constipation. Recently, safety concerns have been raised about a possible interaction between sennosides and digoxin, an issue that has not been studied empirically. This study therefore aimed to evaluate whether exposure to sennoside-digoxin interaction is associated with an increased risk of digoxin toxicity. This was a population-based nested case-control study that analysed data obtained from the Taiwan National Health Insurance Research Database between 1 January 2001 and 31 December 2004. All HF patients treated with digoxin for the first time were included as the study cohort. Of these, cases were identified as subjects hospitalized for digoxin toxicity (International Classification of Diseases, Ninth Revision, Clinical Modification, ICD-9-CM 972.1), and matched to randomly selected controls. Use of sennosides was compared between the two groups. Odds ratios (ORs) were employed to quantify the risk associated with exposure to sennoside-digoxin interaction by conditional logistic regression. The study cohort comprised 222,527 HF patients, of whom 524 were identified as cases and 2,502 as matched controls. Use of sennosides during the 14 days preceding the index date was found to be associated with a 1.61-fold increased risk of digoxin toxicity [95% confidence interval (CI) = 1.15, 2.25]. Additionally, a greater risk was observed for sennosides prescribed at an average daily dose ≥ 24 mg (adjusted OR = 1.93; 95% CI = 1.27, 2.94). The combined use of sennosides and digoxin was found to be associated with a modest increased risk of digoxin toxicity in HF patients.

Proton-pump inhibitors are associated with a reduced risk for bleeding and perforated gastroduodenal ulcers attributable to non-steroidal anti-inflammatory drugs: a nested case-control study

PubMed Central

Vonkeman, Harald E; Fernandes, Robert W; van der Palen, Job; van Roon, Eric N; van de Laar, Mart AFJ

2007-01-01

Treatment with non-steroidal anti-inflammatory drugs (NSAIDs) is hampered by gastrointestinal ulcer complications, such as ulcer bleeding and perforation. The efficacy of proton-pump inhibitors in the primary prevention of ulcer complications arising from the use of NSAIDs remains unproven. Selective cyclooxygenase-2 (COX-2) inhibitors reduce the risk for ulcer complications, but not completely in high-risk patients. This study determines which patients are especially at risk for NSAID ulcer complications and investigates the effectiveness of different preventive strategies in daily clinical practice. With the use of a nested case-control design, a large cohort of NSAID users was followed for 26 months. Cases were patients with NSAID ulcer complications necessitating hospitalisation; matched controls were selected from the remaining cohort of NSAID users who did not have NSAID ulcer complications. During the observational period, 104 incident cases were identified from a cohort of 51,903 NSAID users with 10,402 patient years of NSAID exposure (incidence 1% per year of NSAID use, age at diagnosis 70.4 ± 16.7 years (mean ± SD), 55.8% women), and 284 matched controls. Cases were characterised by serious, especially cardiovascular, co-morbidity. In-hospital mortality associated with NSAID ulcer complications was 10.6% (incidence 21.2 per 100,000 NSAID users). Concomitant proton-pump inhibitors (but not selective COX-2 inhibitors) were associated with a reduced risk for NSAID ulcer complications (the adjusted odds ratio 0.33; 95% confidence interval 0.17 to 0.67; p = 0.002). Especially at risk for NSAID ulcer complications are elderly patients with cardiovascular co-morbidity. Proton-pump inhibitors are associated with a reduced risk for NSAID ulcer complications. PMID:17521422

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.

Molecular forensics in avian conservation: a DNA-based approach for identifying mammalian predators of ground-nesting birds and eggs.

PubMed

Hopken, Matthew W; Orning, Elizabeth K; Young, Julie K; Piaggio, Antoinette J

2016-01-07

The greater sage-grouse (Centrocercus urophasianus) is a ground-nesting bird from the Northern Rocky Mountains and a species at risk of extinction in in multiple U.S. states and Canada. Herein we report results from a proof of concept that mitochondrial and nuclear DNAs from mammalian predator saliva could be non-invasively collected from depredated greater sage-grouse eggshells and carcasses and used for predator species identification. Molecular forensic approaches have been applied to identify predators from depredated remains as one strategy to better understand predator-prey dynamics and guide management strategies. This can aid conservation efforts by correctly identifying predators most likely to impact threatened and endangered species. DNA isolated from non-invasive samples around nesting sites (e.g. fecal or hair samples) is one method that can increase the success and accuracy of predator species identification when compared to relying on nest remains alone. Predator saliva DNA was collected from depredated eggshells and carcasses using swabs. We sequenced two partial fragments of two mitochondrial genes and obtained microsatellite genotypes using canid specific primers for species and individual identification, respectively. Using this multilocus approach we were able to identify predators, at least down to family, from 11 out of 14 nests (79%) and three out of seven carcasses (47%). Predators detected most frequently were canids (86%), while other taxa included rodents, a striped skunk, and cattle. We attempted to match the genotypes of individual coyotes obtained from eggshells and carcasses with those obtained from fecal samples and coyotes collected in the areas, but no genotype matches were found. Predation is a main cause of nest failure in ground-nesting birds and can impact reproduction and recruitment. To inform predator management for ground-nesting bird conservation, accurate identification of predator species is necessary. Considering predation can have a high impact on recruitment, predation events are very difficult to observe, and predator species are difficult to identify visually from nest remains, molecular approaches that reduce the need to observe or handle animals offer an additional tool to better understand predator-prey dynamics at nesting sites.

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.

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.

Tactic changes in dusky frillgoby Bathygobius fuscus sneaker males: effects of body size and nest availability.

PubMed

Takegaki, T; Kaneko, T; Matsumoto, Y

2013-02-01

Field and laboratory studies were conducted to examine the effects of nest availability and body size on changes in male mating tactics from sneaking to nest-holding in the dusky frillgoby Bathygobius fuscus. In the field, the body size of nest-holding males decreased from early to mid-breeding season, suggesting the possibility of a change in the tactics of sneaker males to nest-holding. Many sneaker males did not use vacant spawning nests even when size-matched nests were available, but they continued to reproduce as sneakers. Similarly, in aquarium experiments with available vacant nests, some sneaker males became nest-holders irrespective of their body size, but some did not. These results showed that nest availability is not a limiting factor for changes in tactics by sneaker males in this species. Because tactic-unchanged sneaker males were co-housed with larger nest-holding males in the tanks, the body size of nearby nest-holding males may have affected the decision to change tactics for sneaker males. Moreover, smaller individuals among tactic-changed males tended to spend more time until spawning, probably because they had relatively larger costs and smaller benefits of reproduction as nest-holding males compared to larger males. © 2012 The Authors. Journal of Fish Biology © 2012 The Fisheries Society of the British Isles.

Escape Distance in Ground-Nesting Birds Differs with Individual Level of Camouflage.

PubMed

Wilson-Aggarwal, Jared K; Troscianko, Jolyon T; Stevens, Martin; Spottiswoode, Claire N

2016-08-01

Camouflage is one of the most widespread antipredator strategies in the animal kingdom, yet no animal can match its background perfectly in a complex environment. Therefore, selection should favor individuals that use information on how effective their camouflage is in their immediate habitat when responding to an approaching threat. In a field study of African ground-nesting birds (plovers, coursers, and nightjars), we tested the hypothesis that individuals adaptively modulate their escape behavior in relation to their degree of background matching. We used digital imaging and models of predator vision to quantify differences in color, luminance, and pattern between eggs and their background, as well as the plumage of incubating adult nightjars. We found that plovers and coursers showed greater escape distances when their eggs were a poorer pattern match to the background. Nightjars sit on their eggs until a potential threat is nearby, and, correspondingly, they showed greater escape distances when the pattern and color match of the incubating adult's plumage-rather than its eggs-was a poorer match to the background. Finally, escape distances were shorter in the middle of the day, suggesting that escape behavior is mediated by both camouflage and thermoregulation.

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.).

A nested case-control study of leukemia mortality and ionizing radiation at the Portsmouth Naval Shipyard.

PubMed

Kubale, Travis L; Daniels, Robert D; Yiin, James H; Couch, James; Schubauer-Berigan, Mary K; Kinnes, Gregory M; Silver, Sharon R; Nowlin, Susan J; Chen, Pi-Hsueh

2005-12-01

A nested case-control study using conditional logistic regression was conducted to evaluate the exposure-response relationship between external ionizing radiation exposure and leukemia mortality among civilian workers at the Portsmouth Naval Shipyard (PNS), Kittery, Maine. The PNS civilian workers received occupational radiation exposure while performing construction, overhaul, repair and refueling activities on nuclear-powered submarines. The study age-matched 115 leukemia deaths with 460 controls selected from a cohort of 37,853 civilian workers employed at PNS between 1952 and 1992. In addition to radiation doses received in the workplace, a secondary analysis incorporating doses from work-related medical X rays and other occupational radiation exposures was conducted. A significant positive association was found between leukemia mortality and external radiation exposure, adjusting for gender, radiation worker status, and solvent exposure duration (OR = 1.08 at 10 mSv of exposure; 95% CI = 1.01, 1.16). Solvent exposure (including benzene and carbon tetrachloride) was also significantly associated with leukemia mortality adjusting for radiation dose, radiation worker status, and gender. Incorporating doses from work-related medical X rays did not change the estimated leukemia risk per unit of dose.

Duration of exposure to multiple antibiotics is associated with increased risk of VRE bacteraemia: a nested case-control study.

PubMed

Gouliouris, Theodore; Warne, Ben; Cartwright, Edward J P; Bedford, Luke; Weerasuriya, Chathika K; Raven, Kathy E; Brown, Nick M; Török, M Estée; Limmathurotsakul, Direk; Peacock, Sharon J

2018-03-13

VRE bacteraemia has a high mortality and continues to defy control. Antibiotic risk factors for VRE bacteraemia have not been adequately defined. We aimed to determine the risk factors for VRE bacteraemia focusing on duration of antibiotic exposure. A retrospective matched nested case-control study was conducted amongst hospitalized patients at Cambridge University Hospitals NHS Foundation Trust (CUH) from 1 January 2006 to 31 December 2012. Cases who developed a first episode of VRE bacteraemia were matched 1:1 to controls by length of stay, year, specialty and ward type. Independent risk factors for VRE bacteraemia were evaluated using conditional logistic regression. Two hundred and thirty-five cases were compared with 220 controls. Duration of exposure to parenteral vancomycin, fluoroquinolones and meropenem was independently associated with VRE bacteraemia. Compared with patients with no exposure to vancomycin, those who received courses of 1-3 days, 4-7 days or >7 days had a stepwise increase in risk of VRE bacteraemia [conditional OR (cOR) 1.2 (95% CI 0.4-3.8), 3.8 (95% CI 1.2-11.7) and 6.6 (95% CI 1.9-22.8), respectively]. Other risk factors were: presence of a central venous catheter (CVC) [cOR 8.7 (95% CI 2.6-29.5)]; neutropenia [cOR 15.5 (95% CI 4.2-57.0)]; hypoalbuminaemia [cOR 8.5 (95% CI 2.4-29.5)]; malignancy [cOR 4.4 (95% CI 1.6-12.0)]; gastrointestinal disease [cOR 12.4 (95% CI 4.2-36.8)]; and hepatobiliary disease [cOR 7.9 (95% CI 2.1-29.9)]. Longer exposure to vancomycin, fluoroquinolones or meropenem was associated with VRE bacteraemia. Antimicrobial stewardship interventions targeting high-risk antibiotics are required to complement infection control procedures against VRE bacteraemia.

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.

Social Hackers: Integration in the Host Chemical Recognition System by a Paper Wasp Social Parasite

NASA Astrophysics Data System (ADS)

Turillazzi, S.; Sledge, M. F.; Dani, F. R.; Cervo, R.; Massolo, A.; Fondelli, L.

Obligate social parasites in the social insects have lost the worker caste and the ability to establish nests. As a result, parasites must usurp a host nest, overcome the host recognition system, and depend on the host workers to rear their offspring. We analysed cuticular hydrocarbon profiles of live parasite females of the paper wasp social parasite Polistes sulcifer before and after usurpation of host nests, using the non-destructive technique of solid-phase micro-extraction. Our results reveal that hydrocarbon profiles of parasites change after usurpation of host nests to match the cuticular profile of the host species. Chemical evidence further shows that the parasite queen changes the odour of the nest by the addition of a parasite-specific hydrocarbon. We discuss the possible role of this in the recognition and acceptance of the parasite and its offspring in the host colony.

Social hackers: integration in the host chemical recognition system by a paper wasp social parasite.

PubMed

Turillazzi, S; Sledge, M F; Dani, F R; Cervo, R; Massolo, A; Fondelli, L

2000-04-01

Obligate social parasites in the social insects have lost the worker caste and the ability to establish nests. As a result, parasites must usurp a host nest, overcome the host recognition system, and depend on the host workers to rear their offspring. We analysed cuticular hydrocarbon profiles of live parasite females of the paper wasp social parasite Polistes sulcifer before and after usurpation of host nests, using the non-destructive technique of solid-phase micro-extraction. Our results reveal that hydrocarbon profiles of parasites change after usurpation of host nests to match the cuticular profile of the host species. Chemical evidence further shows that the parasite queen changes the odour of the nest by the addition of a parasite-specific hydrocarbon. We discuss the possible role of this in the recognition and acceptance of the parasite and its offspring in the host colony.

Correlation of CpG Island Methylation of the Cytochrome P450 2E1/2D6 Genes with Liver Injury Induced by Anti-Tuberculosis Drugs: A Nested Case-Control Study.

PubMed

Zhang, Jinling; Zhu, Xuebin; Li, Yuhong; Zhu, Lingyan; Li, Shiming; Zheng, Guoying; Ren, Qi; Xiao, Yonghong; Feng, Fumin

2016-08-01

This study investigated the role of CpG island methylation of the CYP2E1 and CYP2D6 genes in liver injury induced by anti-TB drugs from an epigenetic perspective in a Chinese cohort. A 1:1 matched nested case-control study design was applied. Pulmonary tuberculosis (TB) patients, who underwent standard anti-TB therapy and developed liver injury were defined as cases, while those who did not develop liver injury were defined as control. The two groups were matched in terms of sex, treatment regimen, and age. In 114 pairs of cases, CpG island methylation levels of the CYP2E1 and CYP2D6 genes in plasma cell-free DNA were found to be significantly correlated with the occurrence of anti-TB drug-induced liver injury (ADLI), with odds ratio (OR) values of 2.429 and 3.500, respectively (p < 0.01). Moreover, through multivariate logistic regression analysis, CpG island methylation of the CYP2E1 and CYP2D6 genes in plasma cell-free DNA were found to be significantly correlated with the occurrence of ADLI, with adjusted OR values of 4.390 (95% confidence interval (CI): 1.982-9.724) and 9.193 (95% CI: 3.624-25.888), respectively (p < 0.001). These results suggest that aberrantly elevated methylation of CpG islands of the CYP2E1 and CYP2D6 genes in plasma cell-free DNA may increase the risk of ADLI in Chinese TB patients.

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.

Association between sleep disorder and panic disorder in South Korea: Nationwide nested case-control study of data from 2004 to 2013.

PubMed

Park, Han Jin; Kim, Min Seok; Park, Eun-Cheol; Jang, Suk-Yong; Kim, Woorim; Han, Kyu-Tae

2017-12-05

After 2010, panic disorders became relatively common in South Korea, with many celebrities confessing to the public that they have panic disorder. The annual number of patients with panic disorder and sleep disorder have been gradually increasing. In light of these increases, we analyzed the relationship between sleep disorder and panic disorder. We used national claim data to design a 1:3 nested case-control study. The study included medical claims filed for 29,312 patients during 2004-2013. We performed conditional logistic regression analysis to investigate the relationship between sleep disorder and panic disorder. There were 7436 patients who were diagnosed with panic disorder, and 21,876 patients who were gender- and age-matched as controls. Patients with sleep disorder had higher incidence of panic disorder. In particular, patients with insomnia had the strongest association with panic disorder (adjusted, OR, 1.386; 95% CI, 1.201-1.599; p < 0.05). These associations were stronger in healthy patients and those with worse socioeconomic status. In conclusion, sleep disorder, in particular, insomnia was positively associated with panic disorder. Thus, healthcare professionals and policy makers should effectively control insomnia and consider strategies for early intervention for vulnerable patients with risk of panic disorder. Copyright © 2017. Published by Elsevier B.V.

Atypical prediagnosis Epstein-Barr virus serology restricted to EBV-positive Hodgkin lymphoma

PubMed Central

Chang, Ellen T.; Ambinder, Richard F.; Lennette, Evelyne T.; Rubertone, Mark V.; Mann, Risa B.; Borowitz, Michael; Weir, Edward G.; Abbondanzo, Susan L.; Mueller, Nancy E.

2012-01-01

An altered anti–Epstein-Barr virus (EBV) serologic profile preceding diagnosis is associated with an increased risk of Hodgkin lymphoma. It is unknown whether this atypical pattern predicts Hodgkin lymphoma risk further subdivided by determination of EBV in tumor cells. A nested case-control study of 128 incident Hodgkin lymphoma cases and 368 matched controls from active-duty military personnel with archived serum in the US Department of Defense Serum Repository was conducted to determine whether a panel of anti-EBV antibody titers differed in EBV+ and EBV− Hodgkin lymphoma. Among 40 EBV+ Hodgkin lymphoma cases and matched controls, statistically significant increased risks were associated with elevated anti-EBV VCA IgG antibody titers (relative risk = 3.1; 95% confidence interval [CI], 1.1-8.7), and an anti–EBNA-1/anti–EBNA-2 antibody ratio ≤ 1.0 versus > 1.0 (relative risk = 4.7; 95% CI, 1.6-13.8). In contrast, no significant associations were found among 88 EBV− Hodgkin lymphoma cases relative to their matched controls. In case-case analysis, EBV+ disease was significantly associated with a low anti–EBNA-1/anti–EBNA-2 antibody ratio. This distinc-tive serologic response to EBV latent antigens, indicative of immune dysfunction in other clinical settings, is associated with an increased risk of developing EBV+ but not EBV− Hodgkin lymphoma. PMID:22972983

From neurons to nests: nest-building behaviour as a model in behavioural and comparative neuroscience.

PubMed

Hall, Zachary J; Meddle, Simone L; Healy, Susan D

Despite centuries of observing the nest building of most extant bird species, we know surprisingly little about how birds build nests and, specifically, how the avian brain controls nest building. Here, we argue that nest building in birds may be a useful model behaviour in which to study how the brain controls behaviour. Specifically, we argue that nest building as a behavioural model provides a unique opportunity to study not only the mechanisms through which the brain controls behaviour within individuals of a single species but also how evolution may have shaped the brain to produce interspecific variation in nest-building behaviour. In this review, we outline the questions in both behavioural and comparative neuroscience that nest building could be used to address, summarize recent findings regarding the neurobiology of nest building in lab-reared zebra finches and across species building different nest structures, and suggest some future directions for the neurobiology of nest building.

Egg-laying substrate selection for optimal camouflage by quail.

PubMed

Lovell, P George; Ruxton, Graeme D; Langridge, Keri V; Spencer, Karen A

2013-02-04

Camouflage is conferred by background matching and disruption, which are both affected by microhabitat. However, microhabitat selection that enhances camouflage has only been demonstrated in species with discrete phenotypic morphs. For most animals, phenotypic variation is continuous; here we explore whether such individuals can select microhabitats to best exploit camouflage. We use substrate selection in a ground-nesting bird (Japanese quail, Coturnix japonica). For such species, threat from visual predators is high and egg appearance shows strong between-female variation. In quail, variation in appearance is particularly obvious in the amount of dark maculation on the light-colored shell. When given a choice, birds consistently selected laying substrates that made visual detection of their egg outline most challenging. However, the strategy for maximizing camouflage varied with the degree of egg maculation. Females laying heavily maculated eggs selected the substrate that more closely matched egg maculation color properties, leading to camouflage through disruptive coloration. For lightly maculated eggs, females chose a substrate that best matched their egg background coloration, suggesting background matching. Our results show that quail "know" their individual egg patterning and seek out a nest position that provides most effective camouflage for their individual phenotype. Copyright © 2013 Elsevier Ltd. All rights reserved.

A prospective study of Trichomonas vaginalis and prostate cancer risk among African American men.

PubMed

Fowke, Jay H; Han, Xijing; Alderete, J F; Moses, Kelvin A; Signorello, Lisa B; Blot, William J

2016-04-18

African Americans (AA) have a higher prevalence of Trichomonas vaginalis (Tv) infection and a higher prostate (PC) risk. Past studies suggest an association between Tv seropositivity and PC, and therefore we prospectively investigated this association among AA men. Incident PC cases were individually matched to controls in a nested case-control study within the Southern Community Cohort Study (SCCS). Primary analysis included 296 PC cases and 497 race-matched controls. Levels of Tv antibody response were measured by ELISA in serum collected at baseline. Tv antibody response did not significantly differ between cases and controls overall or within AA participants (253 AA cases). There were no significant associations or trends between levels of Tv response and PC risk or the diagnosis of aggressive PC. We found no evidence of a prospective association between baseline Tv infection and PC risk in AA men. Tv infection in men may have substantial health implications in HIV transmission and reproductive outcomes, but may not impact future PC risk in AA men at high-risk for PC. Further efforts need to define past vs. present Tv infection and to separate pathophysiology from PC detection.

Population Census of a Large Common Tern Colony with a Small Unmanned Aircraft

PubMed Central

Chabot, Dominique; Craik, Shawn R.; Bird, David M.

2015-01-01

Small unmanned aircraft systems (UAS) may be useful for conducting high-precision, low-disturbance waterbird surveys, but limited data exist on their effectiveness. We evaluated the capacity of a small UAS to census a large (>6,000 nests) coastal Common tern (Sterna hirundo) colony of which ground surveys are particularly disruptive and time-consuming. We compared aerial photographic tern counts to ground nest counts in 45 plots (5-m radius) throughout the colony at three intervals over a nine-day period in order to identify sources of variation and establish a coefficient to estimate nest numbers from UAS surveys. We also compared a full colony ground count to full counts from two UAS surveys conducted the following day. Finally, we compared colony disturbance levels over the course of UAS flights to matched control periods. Linear regressions between aerial and ground counts in plots had very strong correlations in all three comparison periods (R 2 = 0.972–0.989, P < 0.001) and regression coefficients ranged from 0.928–0.977 terns/nest. Full colony aerial counts were 93.6% and 94.0%, respectively, of the ground count. Varying visibility of terns with ground cover, weather conditions and image quality, and changing nest attendance rates throughout incubation were likely sources of variation in aerial detection rates. Optimally timed UAS surveys of Common tern colonies following our method should yield population estimates in the 93–96% range of ground counts. Although the terns were initially disturbed by the UAS flying overhead, they rapidly habituated to it. Overall, we found no evidence of sustained disturbance to the colony by the UAS. We encourage colonial waterbird researchers and managers to consider taking advantage of this burgeoning technology. PMID:25874997

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.

Bioavailable serum estradiol may alter radiation risk of postmenopausal breast cancer: a nested case-control study.

PubMed

Grant, Eric J; Cologne, John B; Sharp, Gerald B; Eguchi, Hidetaka; Stevens, Richard G; Izumi, Shizue; Kim, Young-Min; Berrington de González, Amy; Ohishi, Waka; Nakachi, Kei

2018-02-01

Ionizing radiation and high levels of circulating estradiol are known breast cancer carcinogens. We investigated the risk of first primary postmenopausal breast cancer in relation to the combined effects of whole-body ionizing radiation exposure and prediagnostic levels of postmenopausal sex hormones, particularly bioavailable estradiol (bE 2 ). A nested case-control study of 57 incident breast cancer cases matched with 110 controls among atomic bomb survivors. Joint effects of breast radiation dose and circulating levels of sex hormones were assessed using binary regression and path analysis. Radiation exposure, higher levels of bE 2 , testosterone and progesterone, and established reproductive risk factors were positively associated with postmenopausal breast cancer risk. A test for mediation of the effect of radiation via bE 2 level suggested a small (14%) but significant mediation (p = 0.004). The estimated interaction between radiation and bE 2 was large but not significant (interaction = 3.86; p = 0.32). There is accumulating evidence that ionizing radiation not only damages DNA but also alters other organ systems. While caution is needed, some portion of the radiation risk of postmenopausal breast cancer appeared to be mediated through bE 2 levels, which may be evidence for cancer risks due to both direct and indirect effects of radiation.

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

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.

Development of diagnostic prediction tools for bacteraemia caused by third-generation cephalosporin-resistant enterobacteria in suspected bacterial infections: a nested case-control study.

PubMed

Rottier, W C; van Werkhoven, C H; Bamberg, Y R P; Dorigo-Zetsma, J W; van de Garde, E M; van Hees, B C; Kluytmans, J A J W; Kuck, E M; van der Linden, P D; Prins, J M; Thijsen, S F T; Verbon, A; Vlaminckx, B J M; Ammerlaan, H S M; Bonten, M J M

2018-03-23

Current guidelines for the empirical antibiotic treatment predict the presence of third-generation cephalosporin-resistant enterobacterial bacteraemia (3GCR-E-Bac) in case of infection only poorly, thereby increasing unnecessary carbapenem use. We aimed to develop diagnostic scoring systems which can better predict the presence of 3GCR-E-Bac. A retrospective nested case-control study was performed that included patients ≥18 years of age from eight Dutch hospitals in whom blood cultures were obtained and intravenous antibiotics were initiated. Each patient with 3GCR-E-Bac was matched to four control infection episodes within the same hospital, based on blood-culture date and onset location (community or hospital). Starting from 32 commonly described clinical risk factors at infection onset, selection strategies were used to derive scoring systems for the probability of community- and hospital-onset 3GCR-E-Bac. 3GCR-E-Bac occurred in 90 of 22 506 (0.4%) community-onset infections and in 82 of 8110 (1.0%) hospital-onset infections, and these cases were matched to 360 community-onset and 328 hospital-onset control episodes. The derived community-onset and hospital-onset scoring systems consisted of six and nine predictors, respectively. With selected score cut-offs, the models identified 3GCR-E-Bac with sensitivity equal to existing guidelines (community-onset: 54.3%; hospital-onset: 81.5%). However, they reduced the proportion of patients classified as at risk for 3GCR-E-Bac (i.e. eligible for empirical carbapenem therapy) with 40% (95%CI 21-56%) and 49% (95%CI 39-58%) in, respectively, community-onset and hospital-onset infections. These prediction scores for 3GCR-E-Bac, specifically geared towards the initiation of empirical antibiotic treatment, may improve the balance between inappropriate antibiotics and carbapenem overuse. Copyright © 2018 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

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.

Solving LR Conflicts Through Context Aware Scanning

NASA Astrophysics Data System (ADS)

Leon, C. Rodriguez; Forte, L. Garcia

2011-09-01

This paper presents a new algorithm to compute the exact list of tokens expected by any LR syntax analyzer at any point of the scanning process. The lexer can, at any time, compute the exact list of valid tokens to return only tokens in this set. In the case than more than one matching token is in the valid set, the lexer can resort to a nested LR parser to disambiguate. Allowing nested LR parsing requires some slight modifications when building the LR parsing tables. We also show how LR parsers can parse conflictive and inherently ambiguous languages using a combination of nested parsing and context aware scanning. These expanded lexical analyzers can be generated from high level specifications.

Nest odor dynamics in the social wasp Vespula vulgaris

NASA Astrophysics Data System (ADS)

Steinmetz, Inge; Schmolz, Erik

2005-09-01

We investigated nest odor dynamics in the common yellow jacket, Vespula vulgaris. In six isolated colonies, we tested the aggression rates toward dead nestmates that had been stored for 10 min, 10 and 19 days outside their colonies at 76 °C. The aggression rate increased from about 12% toward recently killed nestmates up to 30% toward nestmates killed 19 days before the experiment. Obviously, the conserved nest odor profile of the nestmates frozen for several days did not match with that of their colony anymore. This indicates a change of the nest odor within the colony. In a second experiment, we kept two colonies each in one nest box with a complete separation of both neighbor nests by a solid wall inside the box for 28 days. In confrontation experiments, the colony members treated dead foragers from the neighbor nest as aggressively as dead foreign, non-neighbor workers (about 39% each) whereas only about 14% reacted aggressively toward dead nestmates. Seventeen days after the replacement of the solid wall by a metallic grid, which allowed no physical contact but air exchange between the two neighbor colonies, the aggression rates toward foreign workers and nestmates remained relatively unaffected whereas it decreased significantly toward dead neighbors to about 11%. These results suggest a nest odor dynamic caused by volatiles transferred between two adjacent colonies, resulting in an equalization of the former colony specific nest odors. A change of nest odor dynamics influenced by volatiles was so far described only for one ant species at all.

Maternal Infection during Pregnancy and Autism Spectrum Disorders

PubMed Central

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

2014-01-01

We conducted a nested case-control study including 407 cases and 2075 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 overall association between diagnoses of any maternal infection during pregnancy and ASD (adjusted odds ratio [ORadj] = 1.15, 95% confidence interval [CI] 0.92 – 1.43). However, women with infections diagnosed during a hospital admission (ORadj= 1.48, 95% CI1.07 – 2.04), particularly bacterial infections (ORadj = 1.58, 95% CI 1.06 – 2.37), were at increased risk of delivering a child with ASD. Multiple infections during pregnancy were associated with ASD (ORadj = 1.36, 95% CI 1.05 – 1.78). PMID:24366406

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.

Association between cardiovascular events and sodium-containing effervescent, dispersible, and soluble drugs: nested case-control study

PubMed Central

George, Jacob; Majeed, Waseem; Mackenzie, Isla S; Wei, Li

2013-01-01

Objective To determine whether patients taking formulations of drugs that contain sodium have a higher incidence of cardiovascular events compared with patients on non-sodium formulations of the same drugs. Design Nested case-control study. Setting UK Primary Care Patients registered on the Clinical Practice Research Datalink (CPRD). Participants All patients aged 18 or over who were prescribed at least two prescriptions of sodium-containing formulations or matched standard formulations of the same drug between January 1987 and December 2010. Main outcome measures Composite primary outcome of incident non-fatal myocardial infarction, incident non-fatal stroke, or vascular death. We performed 1:1 incidence density sampling matched controls using the UK Clinical Practice Research Datalink (CPRD). For the secondary analyses, cases were patients with the individual components of the primary study composite endpoint of hypertension, incident heart failure, and all cause mortality. Results 1 292 337 patients were included in the study cohort. Mean follow-up time was 7.23 years. A total of 61 072 patients with an incident cardiovascular event were matched with controls. For the primary endpoint of incident non-fatal myocardial infarction, incident non-fatal stroke, or vascular death the adjusted odds ratio for exposure to sodium-containing drugs was 1.16 (95% confidence interval 1.12 to 1.21). The adjusted odds ratios for the secondary endpoints were 1.22 (1.16 to 1.29) for incident non-fatal stroke, 1.28 (1.23 to 1.33) for all cause mortality, 7.18 (6.74 to 7.65) for hypertension, 0.98 (0.93 to 1.04) for heart failure, 0.94 (0.88 to 1.00) for incident non-fatal myocardial infarction, and 0.70 (0.31 to 1.59) for vascular death. The median time from date of first prescription (that is, date of entry into cohort) to first event was 3.92 years. Conclusions Exposure to sodium-containing formulations of effervescent, dispersible, and soluble medicines was associated with significantly increased odds of adverse cardiovascular events compared with standard formulations of those same drugs. Sodium-containing formulations should be prescribed with caution only if the perceived benefits outweigh these risks. PMID:24284017

Present and future thermal environments available to Sharp-tailed Grouse in an intact grassland.

PubMed

Raynor, Edward J; Powell, Larkin A; Schacht, Walter H

2018-01-01

Better understanding animal ecology in terms of thermal habitat use has become a focus of ecological studies, in large part due to the predicted temperature increases associated with global climate change. To further our knowledge on how ground-nesting endotherms respond to thermal landscapes, we examined the thermal ecology of Sharp-tailed Grouse (Tympanuchus phasianellus) during the nesting period. We measured site-specific iButton temperatures (TiB) and vegetation characteristics at nest sites, nearby random sites, and landscape sites to assess thermal patterns at scales relevant to nesting birds. We asked if microhabitat vegetation characteristics at nest sites matched the characteristics that directed macrohabitat nest-site selection. Grouse selected sites sheltered by dense vegetation for nesting that moderated TiB on average up to 2.7°C more than available landscape sites. Successful nests were positioned in a way that reduced exposure to thermal extremes by as much as 4°C relative to failed nests with an overall mean daytime difference (±SE) of 0.4 ±0.03°C. We found that macrohabitat nest-site selection was guided by dense vegetation cover and minimal bare ground as also seen at the microhabitat scale. Global climate projections for 2080 suggest that TiB at nest sites may approach temperatures currently avoided on the landscape, emphasizing a need for future conservation plans that acknowledge fine-scale thermal space in climate change scenarios. These data show that features of grassland landscapes can buffer organisms from unfavorable microclimatic conditions and highlight how thermal heterogeneity at the individual-level can drive decisions guiding nest site selection.

Present and future thermal environments available to Sharp-tailed Grouse in an intact grassland

PubMed Central

Powell, Larkin A.; Schacht, Walter H.

2018-01-01

Better understanding animal ecology in terms of thermal habitat use has become a focus of ecological studies, in large part due to the predicted temperature increases associated with global climate change. To further our knowledge on how ground-nesting endotherms respond to thermal landscapes, we examined the thermal ecology of Sharp-tailed Grouse (Tympanuchus phasianellus) during the nesting period. We measured site-specific iButton temperatures (TiB) and vegetation characteristics at nest sites, nearby random sites, and landscape sites to assess thermal patterns at scales relevant to nesting birds. We asked if microhabitat vegetation characteristics at nest sites matched the characteristics that directed macrohabitat nest-site selection. Grouse selected sites sheltered by dense vegetation for nesting that moderated TiB on average up to 2.7°C more than available landscape sites. Successful nests were positioned in a way that reduced exposure to thermal extremes by as much as 4°C relative to failed nests with an overall mean daytime difference (±SE) of 0.4 ±0.03°C. We found that macrohabitat nest-site selection was guided by dense vegetation cover and minimal bare ground as also seen at the microhabitat scale. Global climate projections for 2080 suggest that TiB at nest sites may approach temperatures currently avoided on the landscape, emphasizing a need for future conservation plans that acknowledge fine-scale thermal space in climate change scenarios. These data show that features of grassland landscapes can buffer organisms from unfavorable microclimatic conditions and highlight how thermal heterogeneity at the individual-level can drive decisions guiding nest site selection. PMID:29415080

A Bioinformatics Approach for Detecting Repetitive Nested Motifs using Pattern Matching.

PubMed

Romero, José R; Carballido, Jessica A; Garbus, Ingrid; Echenique, Viviana C; Ponzoni, Ignacio

2016-01-01

The identification of nested motifs in genomic sequences is a complex computational problem. The detection of these patterns is important to allow the discovery of transposable element (TE) insertions, incomplete reverse transcripts, deletions, and/or mutations. In this study, a de novo strategy for detecting patterns that represent nested motifs was designed based on exhaustive searches for pairs of motifs and combinatorial pattern analysis. These patterns can be grouped into three categories, motifs within other motifs, motifs flanked by other motifs, and motifs of large size. The methodology used in this study, applied to genomic sequences from the plant species Aegilops tauschii and Oryza sativa , revealed that it is possible to identify putative nested TEs by detecting these three types of patterns. The results were validated through BLAST alignments, which revealed the efficacy and usefulness of the new method, which is called Mamushka.

Worker substance use, workplace problems and the risk of occupational injury: a matched case-control study.

PubMed

Spicer, Rebecca S; Miller, Ted R; Smith, Gordon S

2003-07-01

This study examines the tendency toward problem behavior as an explanation for the relationship between problem substance use and occupational injury. The authors used a matched case-control study nested in a cohort of 26,413 workers, in which cases (n = 3,994) were workers suffering an occupational injury. Five controls per case (n = 19,970) were selected from the cohort of workers active on the day of the injury and matched on job type. Conditional logistic regression modeled the association of problem substance use with occupational injury, controlling for problem behaviors and worker characteristics. Problem substance use was indicated indirectly if any of the following were alcohol/drug-involved during the comparison period: Employee Assistance Program visit, excused absence or disciplinary action. Discipline records identified minor (absenteeism) and serious (dishonesty, theft, assault, harassment, disrespect) problem behaviors during the comparison period. The odds of injury among workers with an indicator of problem substance use was 1.35 (p = .015) times greater than the odds among workers without an indicator, controlling for job type and demographics as well as adjusting for exposure. This ratio declined to 1.21 (p = .138) when problem behaviors were also controlled for. Minor and serious problem behaviors were significantly associated with occupational injury (odds ratio [OR] = 1.73, p < .001, and OR = 2.19, p < .001, respectively), controlling for demographics and substance use. The relationship of problem substance use with occupational injury was weak when problem behaviors were controlled for, suggesting that this relationship, observed in previous studies, may be explained by a workers tendency toward problem behaviors. Workplace injury prevention programs should address the expression of problem behaviors as a complement to drug and alcohol deterrent programs.

Complications of ventilation tube insertion in children with and without cleft palate: a nested case-control comparison.

PubMed

Smillie, Ian; Robertson, Sophie; Yule, Anna; Wynne, David M; Russell, Craig J H

2014-10-01

Optimizing hearing in patients with cleft lip and/or palate (CLP) by early recognition and management of otitis media with effusion is essential for speech development. Some evidence has suggested higher complication rates from ventilation tube (VT) insertion in patients with CLP and has led to a trend not to treat these patients surgically. However, studies have failed to match comparison groups for age and sex. To compare complication rates from VT insertion in pediatric patients with and without CLP. The study used a nested case-control design to evaluate 60 pediatric patients with CLP who underwent VT insertion at a children's hospital. The control group of age- and sex-matched patients was selected from a database of 2943 VT insertions. All patients were administered general anesthesia and underwent VT insertion by a pediatric otorhinolaryngology (ENT) team. The primary outcomes were numbers of otorrhea complications. Secondarily, rates of attendance at an ENT clinic specifically for complications were evaluated. Finally, numbers of complications other than otorrhea were assessed but not statistically analyzed owing to the varied types and low numbers in each group. The control cohort had 151 documented cases of otorrhea compared with 121 in the CLP group (ratio 1.25:1); the difference between groups was not statistically significant (P = .52). There was no significant difference in mean ENT clinic visits per patient for complications between groups (0.80 in the CLP group, 0.78 for controls) (P = .66). Regarding complications other than otorrhea, the control group reported more than the CLP group (43 vs 25; ratio, 1.7:1). Complication rates of VT placement among patients with CLP were not higher than those among patients without CLP. Therefore, treatment with VT insertion should be administered to patients with CLP under the same guidelines as for those without CLP. Indeed, there could be an argument for a shift in practice toward more aggressive treatment of patients with CLP, who are already vulnerable to speech and social developmental delay.

Risk of Injurious Fall and Hip Fracture up to 26 y before the Diagnosis of Parkinson Disease: Nested Case-Control Studies in a Nationwide Cohort.

PubMed

Nyström, Helena; Nordström, Anna; Nordström, Peter

2016-02-01

Low muscle strength has been found in late adolescence in individuals diagnosed with Parkinson disease (PD) 30 y later. This study investigated whether this lower muscle strength also may translate into increased risks of falling and fracture before the diagnosis of PD. Among all Swedish citizens aged ≥50 y in 2005, two nested case-control cohorts were compiled. In cohort I, individuals diagnosed with PD during 1988-2012 (n = 24,412) were matched with up to ten controls (n = 243,363), and the risk of fall-related injuries before diagnosis of PD was evaluated. In cohort II, individuals with an injurious fall in need of emergency care during 1988-2012 (n = 622,333) were matched with one control (n = 622,333), and the risk of PD after the injurious fall was evaluated. In cohort I, 18.0% of cases and 11.5% of controls had at least one injurious fall (p < 0.001) prior to PD diagnosis in the case. Assessed by conditional logistic regression analysis adjusted for comorbid diagnoses and education level, PD was associated with increased risks of injurious fall up to 10 y before diagnosis (odds ratio [OR] 1.19, 95% CI 1.08-1.31; 7 to <10 y before diagnosis) and hip fracture ≥15 y before diagnosis (OR 1.36, 95% CI 1.10-1.69; 15-26 y before diagnosis). In cohort II, 0.7% of individuals with an injurious fall and 0.5% of controls were diagnosed with PD during follow-up (p < 0.001). The risk of PD was increased for up to 10 y after an injurious fall (OR 1.18, 95% CI 1.02-1.37; 7 to <10 y after diagnosis). An important limitation is that the diagnoses were obtained from registers and could not be clinically confirmed for the study. The increased risks of falling and hip fracture prior to the diagnosis of PD may suggest the presence of clinically relevant neurodegenerative impairment many years before the diagnosis of this disease.

The Role of Healthy Lifestyle in the Implementation of Regressing Suboptimal Health Status among College Students in China: A Nested Case-Control Study

PubMed Central

Chen, Jieyu; Xiang, Hongjie; Jiang, Pingping; Yu, Lin; Jing, Yuan; Li, Fei; Wu, Shengwei; Fu, Xiuqiong; Liu, Yanyan; Kwan, Hiuyee; Luo, Ren; Zhao, Xiaoshan; Sun, Xiaomin

2017-01-01

Background: Suboptimal health status (SHS) is the intermediate health state between health and disease, it is medically undiagnosed and is also termed functional somatic syndrome. Although its clinical manifestations are complicated and various, SHS has not reached the disease status. Unhealthy lifestyle is associated with many chronic diseases and mortality. In accordance with the impact of lifestyle on health, it is intriguing to determine the association between unhealthy lifestyle and SHS risk. Methods: We conducted a nested case-control study among healthy Chinese college students from March 2012 to September 2013, which was nested in a prospective cohort of 5676 students. We performed 1:1 incidence density sampling with matched controls for birth year, sex, grade, specialty and individual character. SHS was evaluated using the medical examination report and Sub-health Measurement Scale V1.0 (SHMS V1.0). Exposure was defined as an unhealthy lifestyle per the frequency of six behavioral dimensions from the Health-promoting Lifestyle Profile (HPLP-II). Results: We matched 543 cases of SHS (42.66%) in a cohort of 1273 students during the 1.5 years mean follow-up time with controls. A significant difference (t = 9.79, p < 0.001) and a reduction in HPLP-II total score was present at 1.5 years follow-up (135.93 ± 17.65) compared to baseline (144.48 ± 18.66). A level-response effect was recorded with an increase of the total HPLP-II (every dimension was correlated with a decreased SHS risk). Compared to respondents with the least exposure (excellent level), those reporting a general HPLP-II level were approximately 2.3 times more likely to develop SHS (odd ratio = 2.333, 95% CI = 1.471 to 3.700); and those with less HPLP-II level (good level) were approximately 1.6 times more likely (1.644, 1.119–2.414) to develop SHS (p < 0.05). Our data indicated that unhealthy lifestyle behavior with respect to behavioral dimensions significantly affected SHS likelihood. Further analyses revealed a marked increase (average increased 14.73 points) in lifestyle level among those SHS regression to health after 1.5 years, with respect to the HPLP-II behavioral dimensions, in addition to the total score (t = −15.34, p < 0.001). Conclusions: SHS is highly attributable to unhealthy lifestyles, and the mitigation of modifiable lifestyle risk factors may lead to SHS regression. Increased efforts to modify unhealthy lifestyles are necessary to prevent SHS. PMID:28264509

The Role of Healthy Lifestyle in the Implementation of Regressing Suboptimal Health Status among College Students in China: A Nested Case-Control Study.

PubMed

Chen, Jieyu; Xiang, Hongjie; Jiang, Pingping; Yu, Lin; Jing, Yuan; Li, Fei; Wu, Shengwei; Fu, Xiuqiong; Liu, Yanyan; Kwan, Hiuyee; Luo, Ren; Zhao, Xiaoshan; Sun, Xiaomin

2017-02-28

Suboptimal health status (SHS) is the intermediate health state between health and disease, it is medically undiagnosed and is also termed functional somatic syndrome. Although its clinical manifestations are complicated and various, SHS has not reached the disease status. Unhealthy lifestyle is associated with many chronic diseases and mortality. In accordance with the impact of lifestyle on health, it is intriguing to determine the association between unhealthy lifestyle and SHS risk. We conducted a nested case-control study among healthy Chinese college students from March 2012 to September 2013, which was nested in a prospective cohort of 5676 students. We performed 1:1 incidence density sampling with matched controls for birth year, sex, grade, specialty and individual character. SHS was evaluated using the medical examination report and Sub-health Measurement Scale V1.0 (SHMS V1.0). Exposure was defined as an unhealthy lifestyle per the frequency of six behavioral dimensions from the Health-promoting Lifestyle Profile (HPLP-II). We matched 543 cases of SHS (42.66%) in a cohort of 1273 students during the 1.5 years mean follow-up time with controls. A significant difference (t = 9.79, p < 0.001) and a reduction in HPLP-II total score was present at 1.5 years follow-up (135.93 ± 17.65) compared to baseline (144.48 ± 18.66). A level-response effect was recorded with an increase of the total HPLP-II (every dimension was correlated with a decreased SHS risk). Compared to respondents with the least exposure (excellent level), those reporting a general HPLP-II level were approximately 2.3 times more likely to develop SHS (odd ratio = 2.333, 95% CI = 1.471 to 3.700); and those with less HPLP-II level (good level) were approximately 1.6 times more likely (1.644, 1.119-2.414) to develop SHS (p < 0.05). Our data indicated that unhealthy lifestyle behavior with respect to behavioral dimensions significantly affected SHS likelihood. Further analyses revealed a marked increase (average increased 14.73 points) in lifestyle level among those SHS regression to health after 1.5 years, with respect to the HPLP-II behavioral dimensions, in addition to the total score (t = -15.34, p < 0.001). SHS is highly attributable to unhealthy lifestyles, and the Int. J. Environ. Res. Public Health 2017, 14, 240 2 of 17 mitigation of modifiable lifestyle risk factors may lead to SHS regression. Increased efforts to modify unhealthy lifestyles are necessary to prevent SHS.

Cardiovascular disease and risk of acute pancreatitis in a population-based study.

PubMed

Bexelius, Tomas Sjöberg; Ljung, Rickard; Mattsson, Fredrik; Lagergren, Jesper

2013-08-01

The low-grade inflammation that characterizes cardiovascular disorders may facilitate the development of pancreatitis; therefore, we investigated the connection between cardiovascular disorders and acute pancreatitis. A nested population-based case-control study was conducted in Sweden in 2006-2008. Cases had a first episode of acute pancreatitis diagnosed in the nationwide Patient Register. Controls were matched on age, sex, and calendar year and randomly selected from all Swedish residents (40-84 years old). Exposure to cardiovascular diseases (hypertension, ischemic heart disease, congestive heart failure, and stroke) was identified in the Patient Register. Relative risk of acute pancreatitis was estimated by odds ratios with 95% confidence intervals using logistic regression adjusting for confounders (matching variables, alcohol disease, chronic obstructive pulmonary disease, type 2 diabetes, number of distinct medications, and other cardiovascular diseases). The study included 6161 cases and 61,637 control subjects. Cardiovascular disorders were positively associated with acute pancreatitis (adjusted odds ratio, 1.35; 95% confidence interval, 1.25-1.45). This population-based study indicates an association between cardiovascular disease and acute pancreatitis. Specifically, ischemic heart disease and hypertension seem to increase the risk of acute pancreatitis. Further research is needed to determine causality.

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

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.

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.

Impact of pest control strategies on the arthropodofauna living in bird nests built in nestboxes in pear and apple orchards.

PubMed

Roy, Lise; Bouvier, Jean-Charles; Lavigne, Claire; Galès, Mathieu; Buronfosse, Thierry

2013-08-01

Pesticide applications have a strong impact on biodiversity in agroecosystems. The present study aimed to assess the impact of pest control strategies on the arthropodofauna of Parus major nests built within nestboxes installed in orchards. Unlike many studied groups, these arthropod communities are not in direct contact with pesticide sprays (on account of their being sheltered by nestboxes) and are also unable to move away from the treated area. In this pilot study, we estimated the prevalence and the taxonomic and ecological diversities of arthropodofauna sampled in the nests and assessed the extent to which the whole and nest-specific arthropodofauna were affected by pest control strategies. Sixteen different insect and arachnid Primary Taxonomic Groups (PTGs, order level or below) were found in nests. The best represented PTGs (≥10% occurrence in years 2007 and 2008) were Psocoptera (Insecta, detritivorous/saprophagous), detritivorous/saprophagous Astigmata (Acari) and hematophagous Mesostigmata (Acari). Pest control strategies had a large impact on the prevalence of arthropods in nests, with higher proportions of nests hosting arthropods in organic orchards than in conventional orchards and with intermediate proportions in nests in Integrated Pest Management orchards. In contrast, pest control strategies had no significant effect on the composition of the arthropod communities when only nests hosting nidicolous arthropods were considered.

Camouflage predicts survival in ground-nesting birds

PubMed Central

Troscianko, Jolyon; Wilson-Aggarwal, Jared; Stevens, Martin; Spottiswoode, Claire N.

2016-01-01

Evading detection by predators is crucial for survival. Camouflage is therefore a widespread adaptation, but despite substantial research effort our understanding of different camouflage strategies has relied predominantly on artificial systems and on experiments disregarding how camouflage is perceived by predators. Here we show for the first time in a natural system, that survival probability of wild animals is directly related to their level of camouflage as perceived by the visual systems of their main predators. Ground-nesting plovers and coursers flee as threats approach, and their clutches were more likely to survive when their egg contrast matched their surrounds. In nightjars – which remain motionless as threats approach – clutch survival depended on plumage pattern matching between the incubating bird and its surrounds. Our findings highlight the importance of pattern and luminance based camouflage properties, and the effectiveness of modern techniques in capturing the adaptive properties of visual phenotypes. PMID:26822039

Camouflage predicts survival in ground-nesting birds.

PubMed

Troscianko, Jolyon; Wilson-Aggarwal, Jared; Stevens, Martin; Spottiswoode, Claire N

2016-01-29

Evading detection by predators is crucial for survival. Camouflage is therefore a widespread adaptation, but despite substantial research effort our understanding of different camouflage strategies has relied predominantly on artificial systems and on experiments disregarding how camouflage is perceived by predators. Here we show for the first time in a natural system, that survival probability of wild animals is directly related to their level of camouflage as perceived by the visual systems of their main predators. Ground-nesting plovers and coursers flee as threats approach, and their clutches were more likely to survive when their egg contrast matched their surrounds. In nightjars - which remain motionless as threats approach - clutch survival depended on plumage pattern matching between the incubating bird and its surrounds. Our findings highlight the importance of pattern and luminance based camouflage properties, and the effectiveness of modern techniques in capturing the adaptive properties of visual phenotypes.

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.

The importance of microclimate variation in determining size, growth and survival of avian offspring: experimental evidence from a cavity nesting passerine.

PubMed

Dawson, Russell D; Lawrie, Cheyenne C; O'Brien, Erin L

2005-07-01

Organisms are expected to balance energy allocation in such a way that fitness is maximized. While much research has focussed on allocation strategies of reproducing parents, in particular birds, relatively little attention has been paid to how nestlings allocate energy while in the nest. Nestling birds are faced with a trade-off between devoting energy to growth or to thermoregulation, and in altricial species it is likely that the thermal environment of the nest site influences the nature of this trade-off. Here, we experimentally investigate how altering the microclimate of nests affects the growth, size and survival, as well as cell-mediated immune (CMI) response, of nestling tree swallows (Tachycineta bicolor) in a temperate environment. We place air-activated heating pads in nests of swallows when young were between 4 days and 16 days of age, and compared performance of offspring to control nests. Our manipulation raised temperatures of heated nests by approximately 5 degrees C compared to control nests. Offspring in heated nests had enhanced survival while in the nest, and we also found that they were heavier and had longer ninth primary feathers at 16 days of age. In addition, heating nest boxes resulted in significantly faster growth of primaries, and there was a trend for growth rates of mass to also be higher in heated nests. There were no significant differences between heated and control nests in growth rate or size of tarsus at age 16 days, and we speculate that this lack of response to elevated nest temperatures may be due to growth of skeletal structures being limited by other factors such as calcium availability. We also found no difference between heated and control nests in CMI response. Nonetheless, our results show overall that increasing temperatures of nests has significant benefits that enhance the fitness of offspring. As provisioning rates to offspring did not differ between heated and control nests, we suspect that the beneficial effects of heating were not the consequence of changes in parental behaviour. Our results provide insight into factors, other than food supply, that have important consequences in determining reproductive success of birds breeding in temperate environments.

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.

Can selection on nest size from nest predation explain the latitudinal gradient in clutch size?

PubMed

Biancucci, Luis; Martin, Thomas E

2010-09-01

1. Latitudinal variation in clutch sizes of birds is a well described, but poorly understood pattern. Many hypotheses have been proposed, but few have been experimentally tested, and none have been universally accepted by researchers. 2. The nest size hypothesis posits that higher nest predation in the tropics favours selection for smaller nests and thereby constrains clutch size by shrinking available space for eggs and/or nestlings in the nest. We tested this hypothesis with an experiment in a tropical forest and a comparative study between temperate and tropical field sites. 3. Specifically, we tested if: (i) predation increased with nest size; (ii) tropical birds had smaller nests controlled for body size; and (iii) clutch size was explained by nest size controlled for body size. 4. Experimental swapping of nests of different sizes showed that nest predation increased with nest size in the tropical site. Moreover, nest predation rates were higher in species with larger nests in both sites. However, nest size, corrected for body mass and phylogeny, did not differ between sites and was not related to clutch size between sites. 5. Hence, nest predation can exert selection on nest size as predicted by the hypothesis. Nest size increased with adult body mass, such that adult size might indirectly influence reproductive success through effects on nest size and nest predation risk. Ultimately, however, selection from nest predation on nest size does not explain the smaller clutch sizes typical of the tropics.

Can selection on nest size from nest predation explain the latitudinal gradient in clutch size?

USGS Publications Warehouse

Biancucci, L.; Martin, T.E.

2010-01-01

1. Latitudinal variation in clutch sizes of birds is a well described, but poorly understood pattern. Many hypotheses have been proposed, but few have been experimentally tested, and none have been universally accepted by researchers. 2. The nest size hypothesis posits that higher nest predation in the tropics favours selection for smaller nests and thereby constrains clutch size by shrinking available space for eggs and/or nestlings in the nest. We tested this hypothesis with an experiment in a tropical forest and a comparative study between temperate and tropical field sites. 3. Specifically, we tested if: (i) predation increased with nest size; (ii) tropical birds had smaller nests controlled for body size; and (iii) clutch size was explained by nest size controlled for body size. 4. Experimental swapping of nests of different sizes showed that nest predation increased with nest size in the tropical site. Moreover, nest predation rates were higher in species with larger nests in both sites. However, nest size, corrected for body mass and phylogeny, did not differ between sites and was not related to clutch size between sites. 5. Hence, nest predation can exert selection on nest size as predicted by the hypothesis. Nest size increased with adult body mass, such that adult size might indirectly influence reproductive success through effects on nest size and nest predation risk. Ultimately, however, selection from nest predation on nest size does not explain the smaller clutch sizes typical of the tropics.

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.

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.

Daily Intake of Milk Powder and Risk of Celiac Disease in Early Childhood: A Nested Case-Control Study.

PubMed

Hård Af Segerstad, Elin M; Lee, Hye-Seung; Andrén Aronsson, Carin; Yang, Jimin; Uusitalo, Ulla; Sjöholm, Ingegerd; Rayner, Marilyn; Kurppa, Kalle; Virtanen, Suvi M; Norris, Jill M; Agardh, Daniel

2018-04-28

Milk powder and gluten are common components in Swedish infants' diets. Whereas large intakes of gluten early in life increases the risk of celiac disease in genetically at-risk Swedish children, no study has yet evaluated if intake of milk powder by 2 years of age is associated with celiac disease. A 1-to-3 nested case-control study, comprised of 207 celiac disease children and 621 controls matched for sex, birth year, and HLA genotype, was performed on a birth cohort of HLA-DR3-DQ2 and/or DR4-DQ8-positive children. Subjects were screened annually for celiac disease using tissue transglutaminase autoantibodies (tTGA). Three-day food records estimated the mean intake of milk powder at ages 6 months, 9 months, 12 months, 18 months, and 24 months. Conditional logistic regression calculated odds ratios (OR) at last intake prior to seroconversion of tTGA positivity, and for each time-point respectively and adjusted for having a first-degree relative with celiac disease and gluten intake. Intake of milk powder prior to seroconversion of tTGA positivity was not associated with celiac disease (OR = 1.00; 95% CI = 0.99, 1.03; p = 0.763). In conclusion, intake of milk powder in early childhood is not associated with celiac disease in genetically susceptible children.

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.

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.

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.

Assessments of habitat preferences and quality depend on spatial scale and metrics of fitness

USGS Publications Warehouse

Chalfoun, A.D.; Martin, T.E.

2007-01-01

1. Identifying the habitat features that influence habitat selection and enhance fitness is critical for effective management. Ecological theory predicts that habitat choices should be adaptive, such that fitness is enhanced in preferred habitats. However, studies often report mismatches between habitat preferences and fitness consequences across a wide variety of taxa based on a single spatial scale and/or a single fitness component. 2. We examined whether habitat preferences of a declining shrub steppe songbird, the Brewer's sparrow Spizella breweri, were adaptive when multiple reproductive fitness components and spatial scales (landscape, territory and nest patch) were considered. 3. We found that birds settled earlier and in higher densities, together suggesting preference, in landscapes with greater shrub cover and height. Yet nest success was not higher in these landscapes; nest success was primarily determined by nest predation rates. Thus landscape preferences did not match nest predation risk. Instead, nestling mass and the number of nesting attempts per pair increased in preferred landscapes, raising the possibility that landscapes were chosen on the basis of food availability rather than safe nest sites. 4. At smaller spatial scales (territory and nest patch), birds preferred different habitat features (i.e. density of potential nest shrubs) that reduced nest predation risk and allowed greater season-long reproductive success. 5. Synthesis and applications. Habitat preferences reflect the integration of multiple environmental factors across multiple spatial scales, and individuals may have more than one option for optimizing fitness via habitat selection strategies. Assessments of habitat quality for management prescriptions should ideally include analysis of diverse fitness consequences across multiple ecologically relevant spatial scales. ?? 2007 The Authors.

Autism with intellectual disability related to dynamics of head circumference growth during early infancy.

PubMed

McKeague, Ian W; Brown, Alan S; Bao, Yuanyuan; Hinkka-Yli-Salomäki, Susanna; Huttunen, Jukka; Sourander, Andre

2015-05-01

It is not yet definitively known whether dynamic features of head circumference growth are associated with autism. To address this issue, we carried out a nested matched case-control study using data from national well baby clinics in Finland; autism cases were identified from the Finnish Hospital and Outpatient Discharge Registry. A nonparametric Bayesian method was used to construct growth velocity trajectories between birth and 2 years of age in autism cases and matched control subjects (n = 468 in main analyses, 1:1 matched control subjects). Estimates of odds ratios for autism risk in relation to the growth velocities were obtained using conditional logistic regression. Growth velocity of head circumference at 3 months of age, adjusting for gestational age at birth and maternal age, is significantly associated with autism (p = .014); the finding was observed in subjects with comorbid intellectual disability (ID) (p = .025) but not in those without ID (p = .15). Height growth velocity among subjects with autism and without ID is significantly associated with autism at 6 months (p = .007), and weight growth velocity at 18 months without ID (p = .02) and 24 months without ID (p = .042) and with ID (p = .037). Acceleration in head circumference growth is associated with autism with comorbid ID at 3 months but not subsequently. This association is unrelated to acceleration in height and weight, which are not strongly associated with autism until after 6 months. Copyright © 2015 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

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.

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.

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

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.

Highly controlled nest homeostasis of honey bees helps deactivate phenolics in nectar

NASA Astrophysics Data System (ADS)

Liu, Fanglin; He, Jianzhong; Fu, Wenjun

2005-06-01

Honey bees have a highly developed nest homeostasis, for example, maintaining low CO2 levels and stable nest temperatures at 35°C.We investigate the role of nest homeostasis in deactivating phenolic compounds present in the nectar of Aloe littoralis. We show that the phenolic content in nectar was reduced (from 0.65% to 0.49%) after nectar was incubated in a nest of Apis cerana, and that it was reduced still more (from 0.65% to 0.37%) if nectar was mixed with hypopharyngeal gland proteins (HGP) of worker bees before being placed inside a nest. HGP had little effect on samples outside a nest, indicating that nest conditions are necessary for HGP to deactivate phenolics in nectar. Consequently, the highly controlled nest homeostasis of honey bees facilitates direct deactivation of phenolics in nectar, and plays a role in the action of HGP as well.

Non-tuberculous mycobacterial bloodstream infections in patients with indwelling vascular catheters - the role of sickle cell anaemia.

PubMed

Edun, Babatunde; Shah, Ansal; Durkin, Martin; Whitmire, Melanie; Williams, Shanetta Patterson; Albrecht, Helmut; Al-Hasan, Majdi; Weissman, Sharon

2017-05-01

Few studies have examined risk factors for nontuberculous mycobacteria (NTM) bloodstream infections (BSI) involving indwelling vascular catheters (IDVC). Sickle cell anaemia (HbSS/SC) is known to affect several aspects of the immune system leading to relative immune deficiency. The purpose of this retrospective nested case-control study was to determine if HbSS/SC is a risk factor for NTM BSI among individuals with IDVCs. All NTM IDVC infections (cases) at two tertiary hospitals from 2008 to 2014 were reviewed. Cases were matched 2:1 with controls who had IDVC infections due to organisms other than NTM. Matching criteria included age within 10 years and IDVC infection within three months of index case. Logistic regression was used to identify risk factors for IDVC infection due to NTM. Nineteen NTM BSIs were identified. Three cases were excluded because they did not have IDVCs at the time their BSI was identified. Sixteen cases of NTM IDVC infection were matched to 32 controls with IDVC infections due to other organisms. The mean age of patients with IDVC infections was 48.5 years and 28 (58%) were male. Compared to the control group those with NTM BSI were more likely to have HbSS/SC 38% (6/16) versus 6% (2/32) (p = .006). IDVCs are a risk factor for NTM BSI. Sickle cell anaemia appears to be a risk factor for IDVC infections due to NTM. This study is limited by the small sample size. A larger study is needed to further investigate the association between HbSS/SC and NTM IDVC infections.

Using the entire history in the analysis of nested case cohort samples.

PubMed

Rivera, C L; Lumley, T

2016-08-15

Countermatching designs can provide more efficient estimates than simple matching or case-cohort designs in certain situations such as when good surrogate variables for an exposure of interest are available. We extend pseudolikelihood estimation for the Cox model under countermatching designs to models where time-varying covariates are considered. We also implement pseudolikelihood with calibrated weights to improve efficiency in nested case-control designs in the presence of time-varying variables. A simulation study is carried out, which considers four different scenarios including a binary time-dependent variable, a continuous time-dependent variable, and the case including interactions in each. Simulation results show that pseudolikelihood with calibrated weights under countermatching offers large gains in efficiency if compared to case-cohort. Pseudolikelihood with calibrated weights yielded more efficient estimators than pseudolikelihood estimators. Additionally, estimators were more efficient under countermatching than under case-cohort for the situations considered. The methods are illustrated using the Colorado Plateau uranium miners cohort. Furthermore, we present a general method to generate survival times with time-varying covariates. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

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

PubMed Central

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

2016-01-01

Background: 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. Objectives: 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. Methods: 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. Results: 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. Conclusions: In our statewide nested case–control study population, exposures to both primary and secondary pollutants were associated with an increase in PTB. Citation: 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 PMID:26895492

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.

Male bumblebees perform learning flights on leaving a flower but not when leaving their nest.

PubMed

Robert, Théo; Frasnelli, Elisa; Collett, Thomas S; Hempel de Ibarra, Natalie

2017-03-01

Female bees and wasps demonstrate, through their performance of elaborate learning flights, when and where they memorise features of a significant site. An important feature of these flights is that the insects look back to fixate the site that they are leaving. Females, which forage for nectar and pollen and return with it to the nest, execute learning flights on their initial departure from both their nest and newly discovered flowers. To our knowledge, these flights have so far only been studied in females. Here, we describe and analyse putative learning flights observed in male bumblebees Bombus terrestris L. Once male bumblebees are mature, they leave their nest for good and fend for themselves. We show that, unlike female foragers, males always fly directly away from their nest, without looking back, in keeping with their indifference to their natal nest. In contrast, after males have drunk from artificial flowers, their flights on first leaving the flowers resemble the learning flights of females, particularly in their fixation of the flowers. These differences in the occurrence of female and male learning flights seem to match the diverse needs of the two sexes to learn about disparate, ecologically relevant places in their surroundings. © 2017. Published by The Company of Biologists Ltd.

Identifying effective actions to guide volunteer-based and nationwide conservation efforts for a ground-nesting farmland bird.

PubMed

Santangeli, Andrea; Arroyo, Beatriz; Millon, Alexandre; Bretagnolle, Vincent

2015-08-01

1. Modern farming practices threaten wildlife in different ways, and failure to identify the complexity of multiple threats acting in synergy may result in ineffective management. To protect ground-nesting birds in farmland, monitoring and mitigating impacts of mechanical harvesting is crucial. 2. Here, we use 6 years of data from a nationwide volunteer-based monitoring scheme of the Montagu's harrier, a ground-nesting raptor, in French farmlands. We assess the effectiveness of alternative nest protection measures and map their potential benefit to the species. 3. We show that unprotected nests in cultivated land are strongly negatively affected by harvesting and thus require active management. Further, we show that protection from harvesting alone (e.g. by leaving a small unharvested buffer around the nest) is impaired by post-harvest predation at nests that become highly conspicuous after harvest. Measures that simultaneously protect from harvesting and predation (by adding a fence around the nest) significantly enhance nest productivity. 4. The map of expected gain from nest protection in relation to available volunteers' workforce pinpoints large areas of high expected gain from nest protection that are not matched by equally high workforce availability. This mismatch suggests that the impact of nest protection can be further improved by increasing volunteer efforts in key areas where they are low relative to the expected gain they could have. 5. Synthesis and applications . This study shows that synergistic interplay of multiple factors (e.g. mechanical harvesting and predation) may completely undermine the success of well-intentioned conservation efforts. However, identifying areas where the greatest expected gains can be achieved relative to effort expended can minimize the risk of wasted volunteer actions. Overall, this study underscores the importance of citizen science for collecting large-scale data useful for producing science and ultimately informs large-scale evidence-based conservation actions within an adaptive management framework.

Seroprevalence of Leishmania infection and molecular detection of Leishmania tropica and Leishmania infantum in stray cats of İzmir, Turkey.

PubMed

Can, Hüseyin; Döşkaya, Mert; Özdemir, H Gökhan; Şahar, Esra Atalay; Karakavuk, Muhammet; Pektaş, Bayram; Karakuş, Mehmet; Töz, Seray; Caner, Ayşe; Döşkaya, Aysu Değirmenci; İz, Sultan Gülce; Özbel, Yusuf; Gürüz, Yüksel

2016-08-01

Leishmaniasis caused by more than 20 species of genus Leishmania is transmitted by the bite of infected phlebotomine sand flies. The studies on Leishmania infection in cats is very few in Turkey and therefore we aimed to screen stray cats living in city of İzmir located in western Turkey using nested PCR targeting kinetoplast DNA and serological techniques (ELISA and IFA). Leishmania DNA positive samples were also studied by ITS1 real time PCR. Whole blood and serum samples were obtained from stray cats (n: 1101) living in different counties of İzmir. In serological assays, a serum sample was considered positive in 1:40 dilution in IFA and for ELISA a serum sample was accepted positive when the absorbance value (AV) exceeded the mean AV + Standard Deviation (SD) of the negative control serum samples. According to the results, the seropositivity rates were 10.8% (119/1101) and 15.2% (167/1101) by in house ELISA and IFA, respectively. Among serology coherent samples, the seropositivity rate was 11.1% (116/1047) as detected by both assays after discordant samples (n: 54) were discarded. Of the 1101 stray cats, six (0.54%) were positive by nested PCR while only one of these six samples was positive by ITS1 real time PCR. During PCR, three controls designated as Leishmania infantum, Leishmania tropica, and Leishmania major were used for species identification. According to nested PCR results, L. tropica was identified in two cats (no.76 and 95). In another cat (no. 269), there were two bands in which one of them was well-matched with L. infantum and the other band had ∼850 bp size which does not match with any controls. Remaining three cats (no. 86, 514, and 622) also had the ∼850 bp atypical band size. ITS1 real time PCR detected L. tropica in only one cat (no. 622) which showed an atypical band size in nested PCR. These results indicated that three cats with only one atypical band (no. 86, 514, and 622) and the cat with mixed infection (no. 269) were infected with L. tropica. Altogether, L. tropica was detected in all six DNA positive cats and L. infantum was detected in one cat with mixed infection. In conclusion, although the reservoir role of cats in nature is still unclear the high seroprevalence rate against Leishmania parasites and detecting parasite DNA in stray cats in İzmir indicates that the stray cats are frequently bitten by infected sand flies. Further research activities are required to reveal the frequency of leishmaniasis in cats in different regions of Turkey where Leishmania species are endemic. Copyright © 2016 Elsevier Inc. All rights reserved.

Stabilities of ant nests and their adjacent soils

NASA Astrophysics Data System (ADS)

Echezona, B. C.; Igwe, C. A.

2012-10-01

Nests habour ants and termites and protect them from harsh environmental conditions. The structural stabilities of nests were studied to ascertain their relative vulnerability to environmental stresses. Arboreal-ant nests were pried from different trees, while epigeous-termite nests were excavated from soil surface within the sample area. Soils without any visible sign of ant or termite activity were also sampled 6 m away from the nests as control. Laboratory analysis result showed that irrespective of the tree hosts, the aggregate stabilities of the ant nests were lower than those of the ground termite, with nests formed on Cola nitida significantly showing lower aggregate stability (19.7%) than other antnest structures. Clay dispersion ratio, moisture content, water stable aggregate class <0.25mm and sand mass were each negatively correlated with aggregate stability, while water stable aggregate class1.00-0.50 mm gave a positive correlation. Nest structures were dominated more by water stable aggregate class >2.00 mm but path analysis demonstrated that water stable aggregate class <0.25 mm contributed most to the higher aggregate stability of the termite nest than the other nest. Nest aggregates had greater structural stability compared to the control soil. The higher structural stability of termite nests over other nest and soil was considered a better adaptive mechanism against body desiccation.

Neonatal antecedents for cerebral palsy in extremely preterm babies and interaction with maternal factors.

PubMed

Tran, Uyen; Gray, Peter H; O'Callaghan, Michael J

2005-06-01

Preterm delivery is associated with an increased risk of cerebral palsy (CP). The greatest risk is for infants born <28 weeks' gestation. To identify significant neonatal risk factors for CP and explore the interactions between antenatal and neonatal risk factors, among extremely preterm infants of 27 weeks' gestation or less. Nested case control design. Infants born between 1989 and 1996, at 24-27 weeks' gestation, were evaluated: 30 with CP at 2 years corrected age and 120 control infants matched for gestation age. Neonatal variables were compared using matched analyses with the interaction between antenatal and neonatal factors being examined using logistic regression analyses. Risk factors for CP on matched analyses included patent ductus arteriosus requiring surgical ligation, peri-intraventricular haemorrhage, moderate to severe ventricular dilatation, periventricular leukomalacia (PVL) and need for home oxygen. Independent neonatal predictors were ventricular dilatation (OR 7.3; 95% CI 1.6, 32.3), PVL (OR 29.8; 95% CI 5.6, 159.1) and home oxygen use (OR 3.4; 95% CI 1.2, 9.4). No interaction terms in the logistic models were significant between the previously identified pregnancy risk factors of absence of antenatal steroids and intrauterine growth restriction and the neonatal risk factors. PVL is the most powerful independent predictor of CP in extremely preterm infants of 27 weeks' gestation or less and appears to be uninfluenced by antenatal factors.

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

Cumulative exposure to biologics and risk of cancer in psoriasis patients: A meta-analysis of Psonet studies from Israel, Italy, Spain, United Kingdom and Republic of Ireland.

PubMed

Garcia-Doval, I; Descalzo, M A; Mason, K J; Cohen, A D; Ormerod, A D; Gómez-García, F J; Cazzaniga, S; Feldhamer, I; Ali, H; Herrera-Acosta, E; Griffiths, C E M; Stern, R; Naldi, L

2018-05-03

Cancer risk following long-term exposure to systemic immunomodulatory therapies in psoriasis patients is possible. To assess a dose-response relationship between cumulative length of exposure to biologic therapy and risk of cancer. Four national studies (a healthcare database from Israel, and prospective cohorts form Italy, Spain and UK/ROI) collaborating through Psonet (European Registry of Psoriasis) participated in these nested case-control studies, including nearly 60.000 person-years of observation. Cases were patients who developed an incident cancer. Patients with previous cancers and benign or in-situ tumours were excluded. Four cancer-free controls were matched to each case on year of birth, gender, geographic area, and registration year. Follow-up for controls was censored at the date of cancer diagnosis for the matched case. Conditional logistic regression was performed by each registry. Results were pooled using random effects meta-analysis. 728 cases and 2671 controls were identified. After matching, differences between cases and controls were present for the Charlson comorbidity index in all three registries, and in the prevalence of previous exposure to psoralen-ultraviolet-A (PUVA) and smoking (BADBIR only). The risk of first cancers was not significantly associated with cumulative exposure to biologics (adjusted odds ratio per year of exposure 1.02; 95%CI 0.92, 1.13). Results were similar if squamous and basal cell carcinomas were included in the outcome. Cumulative length of exposure to biologic therapies of psoriasis patients in real-world clinical practice does not appear to be linked to a higher risk of cancer after several years of use. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

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

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.

Methods for excluding cliff swallows from nesting on highway structures.

DOT National Transportation Integrated Search

2009-08-01

Cliff swallows (Petrochelidon pyrrhonota) are colonially breeding migratory birds that frequently nest on highway : structures. Protected by the Migratory Bird Treaty Act of 1918, nesting control methods cannot harm swallows or active : nests. This c...

A nested case-control study of fatal work related injuries among Brazilian steel workers.

PubMed Central

Barreto, S M; Swerdlow, A J; Smith, P G; Higgins, C D

1997-01-01

OBJECTIVES: To estimate the relative risk of death from work related injury in a steelworks, associated with exposure to various occupational hazards, sociodemographic factors, and medical history. MATERIAL AND METHODS: The study was a nested case-control design. It was based on a cohort of men employed in the steel plant of USIMINAS, Brazil between January 1977 and August 1990, who were followed up to November 1992. The cases were defined as all workers in the cohort who died from injury in the study period and whose death had been notified to the Brazilian Ministry of Labour as being related to work. Four controls per case, matched to cases on year of birth, were randomly selected from among workers employed in the plant at the time of death of the matching case. Data on potential risk factors for occupational injury were extracted from company records; for the controls these data were abstracted for the period preceding the death of the matching case. RESULTS: There were 37 deaths related to work injuries during the study period. Four surviving workers were selected as controls for each case, but for eight the personnel records were incomplete, leaving 140 controls in all. Significantly increased risk of fatal injury related to work was associated with exposure to noise, heat, dust and fumes, gases and vapours, rotating shift work, being a manual worker, and working in the steel mill, coke ovens, blast furnaces, and energy and water supply areas. Risk of fatal injury related to work increased with intensity of exposure to noise (P (trend) = 0.004) and heat (P < 0.001), and increased greatly with a hazard score that combined information on noise, heat, dust, and gas exposure (P < 0.001). Number of years of schooling (P = 0.03) and salary level (P = 0.03) were both negatively associated with risk. In a multivariate analysis including all these significant factors, only hazard score and area of work remained associated with death from injury related to work. The highest risks were for men exposed to all four environmental hazards (odds ratio (OR) 19.4; 95% confidence interval (95% CI) 1.1 to 352.1) and those working in the energy supply area (OR 18.0; 1.6 to 198.1). CONCLUSIONS: The study identified parts of the steelworks and types of hazard associated with greatly increased risk of fatal accident. Research and measures to prevent accidents need to concentrate on these areas and the people working in them. The use of a hazard score was successful in identifying high risk, and similar scoring might prove useful in other industrial situations. PMID:9326164

Response of predators to Western Sandpiper nest exclosures

USGS Publications Warehouse

Niehaus, Amanda C.; Ruthrauff, Daniel R.; McCaffery, Brian J.

2004-01-01

In 2001, predator exclosures were used to protect nests of the Western Sandpiper (Calidris mauri) in western Alaska. During the exclosure experiment, nest contents in exclosures had significantly higher daily survival rates than control nests, however, late in the study predators began to cue in on exclosures and predate the nest contents. An Arctic Fox (Alopex lagopus) dug under one exclosure and took the newly hatched chicks, and Long-tailed Jaegers (Stercorarius longicaudus) learned to associate exclosures with active nests and repeatedly visited them. The jaegers attempted to gain access to exclosed nests and pursued adult sandpipers as they emerged from the exclosures. The exclosures were removed to reduce potential mortality to adult and young sandpipers, but subsequently, post-exclosure nests had lower daily survival rates than controls during the same time period. Predation of post-exclosure eggs and chicks highlighted the lasting influence of the exclosure treatment on offspring survival because predators probably remembered nest locations. Researchers are urged to use caution when considering use of predator exclosures in areas where jaegers occur.

rhBMP-2 protects against reoperation for pseudoarthrosis and/or instrumentation failure: A matched case-control study of 448 patients.

PubMed

Macki, Mohamed; Syeda, Sbaa; Kerezoudis, Panagiotis; Bydon, Ali; Witham, Timothy F; Sciubba, Daniel M; Wolinsky, Jean-Paul; Bydon, Mohamad; Gokaslan, Ziya

2016-10-01

The objective of this independent study is to determine the impact of recombinant human bone morphogenetic protein 2 (rhBMP-2) on reoperation for pseudarthrosis and/or instrumentation failure. A nested case-control study of first-time posterolateral, instrumented fusion of the lumbar spine for degenerative spinal disease was undertaken. Cases of reoperation for pseudoarthrosis and/or instrumentation failure were assigned to controls, who did not experience the primary outcome measure at the time of reoperation. Cases and controls were matched on number of interspaces fused and inclusion of interbody. Predictors of reoperation for pseudoarthrosis and/or instrumentation failure were assessed with a conditional logistical regression controlling for rhBMP-2, age, obesity, and smoking. Of the 448 patients, 155 cases of reoperation for pseudoarthrosis and/or instrumentation were matched with 293 controls. Twenty-six percent of first-time surgeries included rhBMP-2, which was statistically more commonly used in the control cohort (33.11%) versus the case cohort (12.90%) (Unadjusted odds ratio [ORunadj]=0.28) (95% confidence interval [CI]: 0.16-0.49). Following a multivariate analysis controlling for age, obesity, and smoking, the rhBMP-2 recipients incurred a 73% lower odds of reoperation for pseudoarthrosis and/or instrumentation failure (95% CI, 0.15-0.48). Neither sarcomatous nor osseous neoplasm was detected in the study population. Mean follow up did not differ between the cases (81.57±standard deviation [SD] 4.98months) versus controls (74.75±2.49month) (ORunadj=1.01) (95% CI: 1.00-1.01). rhBMP-2 in lumbar fusion constructs protects against reoperation for pseudoarthrosis and/or instrumentation failure. However, the decision to include fusion supplements should be weighted between surgical determinants and clinical outcomes. Copyright © 2016 Elsevier Ltd. All rights reserved.

Real-world antidiabetic drug use and fracture risk in 12,277 patients with type 2 diabetes mellitus: a nested case-control study.

PubMed

Losada, E; Soldevila, B; Ali, M S; Martínez-Laguna, D; Nogués, X; Puig-Domingo, M; Díez-Pérez, A; Mauricio, D; Prieto-Alhambra, D

2018-06-02

We conducted a nested case-control study to study the association between antidiabetic treatments (alone or in combination) use and fracture risk among incident type 2 Diabetes mellitus patients. We found an increased risk of bone fracture with insulin therapy compared to metformin monotherapy. Patients with type 2 diabetes mellitus (T2DM) have an increased risk of fragility fractures, to which antidiabetic therapies may contribute. We aimed to characterize the risk of fracture associated with different antidiabetic treatments as usually prescribed to T2DM patients in actual practice conditions. A case-control study was nested within a cohort of incident T2DM patients registered in 2006-2012 in the Information System for Research Development in Primary Care (Catalan acronym, SIDIAP), a database which includes records for > 5.5 million patients in Catalonia (Spain). Each case (incident major osteoporotic fracture) was risk-set matched with up to five same-sex controls by calendar year of T2DM diagnosis and year of birth (± 10 years). Study exposure included previous use of all antidiabetic medications (alone or in combination), as dispensed in the 6 months before the index date, with metformin (MTF) monotherapy, the most commonly used drug, as a reference group (active comparator). Data on 12,277 T2DM patients (2049 cases and 10,228 controls) were analyzed. Insulin use was associated with increased fracture risk (adjusted OR 1.63 (95% CI 1.30-2.04)), as was the combination of MTF and sulfonylurea (SU) (adjusted OR 1.29 (1.07-1.56)), compared with MTF monotherapy. Sensitivity analyses suggest possible causality for insulin therapy but not for the MTF + SU combination association. No significant association was found with any other antidiabetic medications. Insulin monotherapy was associated with an increased fracture risk compared to MTF monotherapy in T2DM patients. Fracture risk should be taken into account when starting a glucose-lowering drug as part of T2DM treatment.

Ischaemic cardiac events and use of strontium ranelate in postmenopausal osteoporosis: a nested case-control study in the CPRD.

PubMed

Cooper, C; Fox, K M; Borer, J S

2014-02-01

We explored the cardiac safety of the osteoporosis treatment strontium ranelate in the UK Clinical Practice Research Datalink. While known cardiovascular risk factors like obesity and smoking were associated with increased cardiac risk, use of strontium ranelate was not associated with any increase in myocardial infarction or cardiovascular death. It has been suggested that strontium ranelate may increase risk for cardiac events in postmenopausal osteoporosis. We set out to explore the cardiac safety of strontium ranelate in the Clinical Practice Research Datalink (CPRD) and linked datasets. We performed a nested case-control study. Primary outcomes were first definite myocardial infarction, hospitalisation with myocardial infarction, and cardiovascular death. Cases and matched controls were nested in a cohort of women treated for osteoporosis. The association with exposure to strontium ranelate was analysed by multivariate conditional logistic regression. Of the 112,445 women with treated postmenopausal osteoporosis, 6,487 received strontium ranelate. Annual incidence rates for first definite myocardial infarction (1,352 cases), myocardial infarction with hospitalisation (1,465 cases), and cardiovascular death (3,619 cases) were 3.24, 6.13, and 14.66 per 1,000 patient-years, respectively. Obesity, smoking, and cardiovascular treatments were associated with significant increases in risk for cardiac events. Current or past use of strontium ranelate was not associated with increased risk for first definite myocardial infarction (odds ratio [OR] 1.05, 95 % confidence interval [CI] 0.68-1.61 and OR 1.12, 95 % CI 0.79-1.58, respectively), hospitalisation with myocardial infarction (OR 0.84, 95 % CI 0.54-1.30 and OR 1.17, 95 % CI 0.83-1.66), or cardiovascular death (OR 0.96, 95 % CI 0.76-1.21 and OR 1.16, 95 % CI 0.94-1.43) versus patients who had never used strontium ranelate. Analysis in the CPRD did not find evidence for a higher risk for cardiac events associated with the use of strontium ranelate in postmenopausal osteoporosis.

Age and breeding success related to nest position in a White stork Ciconia ciconia colony

NASA Astrophysics Data System (ADS)

Vergara, Pablo; Aguirre, José I.

2006-11-01

Coloniality is a breeding system that may produce benefits in terms of breeding success, although these advantages could vary according to factors such as colony size or nest position. We studied breeder's age in relation to nest position (peripheral or central) within the colony. In addition, we studied the relationship between breeding success and nest position, controlling for breeder's age, a highly correlated factor, in a White Stork Ciconia ciconia colony over a 7-year period. Our results show that central nests are mainly occupied by adult birds and had lower failure rates. However, controlling for breeder's age, nest position per se did not explain breeding success. The scarce predation and the lack of human disturbance in the study colony could explain the absence of differences in breeding success between different nest positions within the colony.

OPG and sRANKL serum levels and incident hip fracture in postmenopausal Caucasian women in the Women's Health Initiative Observational Study.

PubMed

LaCroix, Andrea Z; Jackson, Rebecca D; Aragaki, Aaron; Kooperberg, Charles; Cauley, Jane A; Chen, Zhao; Leboff, Meryl S; Duggan, David; Wactawski-Wende, Jean

2013-10-01

The osteoprotogerin/receptor activator of NF-kappa β/receptor activator of NF-kappa β ligand (OPG/RANK/RANKL) pathway plays a critical role in bone remodeling. This study investigated associations between serum levels of OPG, soluble RANKL (sRANKL), and the ratio of OPG/sRANKL to risk of incident hip fracture. A nested case-control study was conducted among postmenopausal, Caucasian women aged 50-79 at baseline (1993-1998), followed for hip fracture through March 2005 in the Women's Health Initiative Observational Study. 400 incident hip fracture cases were selected and individually matched to 400 controls with no prior fracture or incident hip fracture. Matching factors were baseline age, enrollment date and hormone therapy (HT) exposure. Baseline serum OPG and sRANKL levels were measured using high sensitivity ELISA. Odds ratios were computed for quartiles of each biomarker adjusting for matching factors and hip fracture risk factors. Serum OPG was significantly associated with older age, low physical activity and poorer physical function in control women. sRANKL was inversely associated with total calcium intake in control women, but not associated with age or other fracture risk factors. The odds ratio for hip fracture comparing the highest to lowest quartiles of OPG was 2.28 (95% confidence interval (CI), 1.45-3.61) after adjusting for the matching variables (p-value for linear trend <0.001), and 1.87 (95% CI, 1.15-3.04; p for linear trend=0.02) after adjusting for self-rated health status, physical activity and physical functioning. No significant associations between sRANKL or the ratio of OPG/sRANKL and hip fracture risk were observed. Serum OPG levels were independently associated with a nearly twofold increased risk of hip fracture in postmenopausal women. Copyright © 2013 Elsevier Inc. All rights reserved.

OPG and sRANKL serum levels and incident hip fracture in postmenopausal Caucasian women in the Women's Health Initiative Observational Study

PubMed Central

LaCroix, Andrea Z.; Jackson, Rebecca D.; Aragaki, Aaron; Kooperberg, Charles; Cauley, Jane A.; Chen, Zhao; LeBoff, Meryl S.; Duggan, David; Wactawski-Wende, Jean

2013-01-01

Purpose The osteoprotogerin/receptor activator of NF-kappa β/receptor activator of NF-kappa β ligand (OPG/RANK/RANKL) pathway plays a critical role in bone remodeling. This study investigated associations between serum levels of OPG, soluble RANKL (sRANKL), and the ratio of OPG/sRANKL to risk of incident hip fracture. Methods A nested case–control study was conducted among postmenopausal, Caucasian women aged 50–79 at baseline (1993–1998), followed for hip fracture through March 2005 in the Women's Health Initiative Observational Study. 400 incident hip fracture cases were selected and individually matched to 400 controls with noprior fracture or incident hip fracture. Matching factors were baseline age, enrollment date and hormone therapy (HT) exposure. Baseline serum OPG and sRANKL levels were measured using high sensitivity ELISA. Odds ratios were computed for quartiles of each biomarker adjusting for matching factors and hip fracture risk factors. Results Serum OPG was significantly associated with older age, low physical activity and poorer physical function in control women. sRANKL was inversely associated with total calcium intake in control women, but not associated with age or other fracture risk factors. The odds ratio for hip fracture comparing the highest to lowest quartiles of OPG was 2.28 (95% confidence interval (CI), 1.45–3.61) after adjusting for the matching variables (p-value for linear trend <0.001), and 1.87 (95% CI, 1.15–3.04; p for linear trend = 0.02) after adjusting for self-rated health status, physical activity and physical functioning. No significant associations between sRANKL or the ratio of OPG/sRANKL and hip fracture risk were observed. Conclusion Serum OPG levels were independently associated with a nearly twofold increased risk of hip fracture in postmenopausal women. PMID:23735608

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.

Exposure to bacterial products lipopolysaccharide and flagellin and hepatocellular carcinoma: a nested case-control study.

PubMed

Fedirko, Veronika; Tran, Hao Quang; Gewirtz, Andrew T; Stepien, Magdalena; Trichopoulou, Antonia; Aleksandrova, Krasimira; Olsen, Anja; Tjønneland, Anne; Overvad, Kim; Carbonnel, Franck; Boutron-Ruault, Marie-Christine; Severi, Gianluca; Kühn, Tilman; Kaaks, Rudolf; Boeing, Heiner; Bamia, Christina; Lagiou, Pagona; Grioni, Sara; Panico, Salvatore; Palli, Domenico; Tumino, Rosario; Naccarati, Alessio; Peeters, Petra H; Bueno-de-Mesquita, H B; Weiderpass, Elisabete; Castaño, José María Huerta; Barricarte, Aurelio; Sánchez, María-José; Dorronsoro, Miren; Quirós, J Ramón; Agudo, Antonio; Sjöberg, Klas; Ohlsson, Bodil; Hemmingsson, Oskar; Werner, Mårten; Bradbury, Kathryn E; Khaw, Kay-Tee; Wareham, Nick; Tsilidis, Konstantinos K; Aune, Dagfinn; Scalbert, Augustin; Romieu, Isabelle; Riboli, Elio; Jenab, Mazda

2017-04-04

Leakage of bacterial products across the gut barrier may play a role in liver diseases which often precede the development of liver cancer. However, human studies, particularly from prospective settings, are lacking. We used a case-control study design nested within a large prospective cohort to assess the association between circulating levels of anti-lipopolysaccharide (LPS) and anti-flagellin immunoglobulin A (IgA) and G (IgG) (reflecting long-term exposures to LPS and flagellin, respectively) and risk of hepatocellular carcinoma. A total of 139 men and women diagnosed with hepatocellular carcinoma between 1992 and 2010 were matched to 139 control subjects. Multivariable rate ratios (RRs), including adjustment for potential confounders, hepatitis B/C positivity, and degree of liver dysfunction, were calculated with conditional logistic regression. Antibody response to LPS and flagellin was associated with a statistically significant increase in the risk of hepatocellular carcinoma (highest vs. lowest quartile: RR = 11.76, 95% confidence interval = 1.70-81.40; P trend  = 0.021). This finding did not vary substantially by time from enrollment to diagnosis, and did not change after adjustment for chronic infection with hepatitis B and C viruses. These novel findings, based on exposures up to several years prior to diagnosis, support a role for gut-derived bacterial products in hepatocellular carcinoma development. Further study into the role of gut barrier failure and exposure to bacterial products in liver diseases is warranted.

Lung Cancer Risk from Occupational and Environmental Radon and Role of Smoking in Two Czech Nested Case-Control Studies

PubMed Central

Tomasek, Ladislav

2013-01-01

The aim of the present study was to evaluate the risk of lung cancer from combined exposure to radon and smoking. Methodologically, it is based on case-control studies nested within two Czech cohort studies of nearly 11,000 miners followed-up for mortality in 1952–2010 and nearly 12,000 inhabitants exposed to high levels of radon in homes, with mortality follow-up in 1960–2010. In addition to recorded radon exposure, these studies use information on smoking collected from the subjects or their relatives. A total of 1,029 and 370 cases with smoking information have been observed in the occupational and environmental (residential) studies, respectively. Three or four control subjects have been individually matched to cases according to sex, year of birth, and age. The combined effect from radon and smoking is analyzed in terms of geometric mixture models of which the additive and multiplicative models are special cases. The resulting models are relatively close to the additive interaction (mixing parameter 0.2 and 0.3 in the occupational and residential studies, respectively). The impact of the resulting model in the residential radon study is illustrated by estimates of lifetime risk in hypothetical populations of smokers and non-smokers. In comparison to the multiplicative risk model, the lifetime risk from the best geometric mixture model is considerably higher, particularly in the non-smoking population. PMID:23470882

NO2, as a marker of air pollution, and recurrent wheezing in children: a nested case-control study within the BAMSE birth cohort.

PubMed

Emenius, G; Pershagen, G; Berglind, N; Kwon, H-J; Lewné, M; Nordvall, S L; Wickman, M

2003-11-01

To investigate the association between air pollution, including with NO2, and recurrent wheezing during the first two years of life. A birth cohort (BAMSE) comprised 4089 children, for whom information on exposures, symptoms, and diseases was available from parental questionnaires at ages 2 months, and 1 and 2 years. NO2 was measured during four weeks in and outside the dwellings of children with recurrent wheezing and two age matched controls, in a nested case-control study (540 children). Conditional logistic regression showed an OR of 1.60 (95% CI 0.78 to 3.26) among children in the highest quartile of outdoor NO2 exposure in relation to those in the lowest quartile, adjusted for potential confounders. The corresponding OR for indoor NO2 was 1.51 (95% CI 0.81 to 2.82). An interaction with environmental tobacco smoke (ETS) was indicated with an OR of 3.10 (95% CI 1.32 to 7.30) among children exposed to the highest quartile of indoor NO2 and ETS. The association between NO2 and recurrent wheezing appeared stronger in children who did not fulfil the criteria for recurrent wheezing until their second year. Although the odds of increased recurrent wheezing are not statistically significantly different from one, results suggest that exposure to air pollution including NO2, particularly in combination with exposure to ETS, increases the risk of recurrent wheezing in children.

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.

Risk Factors for Symptomatic Avascular Necrosis in Childhood-onset Systemic Lupus Erythematosus.

PubMed

Yang, Yelin; Kumar, Sathish; Lim, Lily Siok Hoon; Silverman, Earl D; Levy, Deborah M

2015-12-01

To examine the frequency and risk factors for symptomatic avascular necrosis (AVN) in childhood-onset systemic lupus erythematosus (cSLE). A single-center, nested, matched, case-control design was used. There were 617 patients with cSLE followed at the Hospital for Sick Children (SickKids) Lupus Clinic between July 1982 and June 2013 included in the study. The AVN cohort consisted of 37 patients identified with clinical findings of symptomatic AVN and diagnosis was confirmed by 1 or more imaging modalities. Three controls were matched to each patient with AVN by date and age at diagnosis. Baseline clinical, laboratory, and treatment characteristics were compared between patients with AVN and controls by univariable analyses and if statistically significant, were included in a multivariable logistic regression model. A total of 37/617 patients (6%) developed symptomatic AVN in 91 joints during followup at SickKids. The mean duration to disease was 2.3 years. The hip was the most commonly involved joint (26/37, 70%). Compared with the matched non-AVN cohort, patients with AVN had a higher incidence of central nervous system (CNS) involvement and nephritis, required greater cumulative prednisone (PRED) from cSLE diagnosis to AVN, received a greater maximal daily PRED dose, and had more frequent use of pulse methylprednisolone therapy. Multivariable regression analysis confirmed major organ involvement (CNS disease and/or nephritis) and maximal daily PRED dose as significant predictors of symptomatic AVN development. Patients with cSLE with severe organ involvement including nephritis and CNS disease and higher maximal daily dose of PRED are more likely to develop symptomatic AVN.

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.

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.

Long-Term Survival and Quality of Life After Transfusion-Associated Pulmonary Edema in Critically III Medical Patients

PubMed Central

Kojicic, Marija; Reriani, Martin K.; Fernández Pérez, Evans R.; Thakur, Lokendra; Kashyap, Rahul; Van Buskirk, Camille M.; Gajic, Ognjen

2010-01-01

Background: Transfusion-related acute lung injury (TRALI) and transfusion-associated circulatory overload (TACO) commonly complicate transfusion in critically ill patients. Prior outcome studies of TACO and TRALI have focused on short-term morbidity and mortality, but the long-term survival and quality of life (QOL) of these patients remain unknown. Methods: In a nested case-control study, we compared survival and QOL between critically ill medical patients who developed pulmonary edema after transfusion (TRALI or TACO) and medical critically ill transfused controls, matched by age, gender, and admission diagnostic group. QOL in survivors was assessed with a 36-item short form health survey 1 year after initial hospitalization. Results: Hospital, 1-year, and 2-year mortality among the 74 TRALI cases and 74 matched controls were 43.2% vs 24.3% (P = .020), 63.8% vs 46.4% (P = .037) and 74.3% vs 54.3% (P = .031), whereas among the 51 TACO cases and 51 matched controls these values were 7.8% vs 11.8% (P = .727), 38.0% vs 28.0% (P = .371), and 44.9% vs 38.8% (P = .512). When adjusted for age and baseline severity of illness in a Cox proportional hazard analysis, the development of TRALI remained associated with decreased survival (hazard ratio 1.86; 95% CI, 1.19-2.93; P = .006). Both TRALI (P = .006, P = .03) and TACO (P = .03, P = .049) were associated with prolonged ICU and hospital lengths of stay. Conclusions: In critically ill medical patients, development of TRALI, but not TACO, is independently associated with decreased long-term survival. PMID:19837827

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/.

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.

Plasma Soluble CD30 as a Possible Marker of Adult T-cell Leukemia in HTLV-1 Carriers: a Nested Case-Control Study.

PubMed

Takemoto, Shigeki; Iwanaga, Masako; Sagara, Yasuko; Watanabe, Toshiki

2015-01-01

Elevated levels of soluble CD30 (sCD30) are linked with various T-cell neoplasms. However, the relationship between sCD30 levels and the development of adult T-cell leukemia (ATL) in human T-cell leukemia virus type 1 (HTLV-1) carriers remains to be clarified. We here investigated whether plasma sCD30 is associated with risk of ATL in a nested case-control study within a cohort of HTLV-1 carriers. We compared sCD30 levels between 11 cases (i.e., HTLV-1 carriers who later progressed to ATL) and 22 age-, sex- and institution-matched control HTLV-1 carriers (i.e., those with no progression). The sCD30 concentration at baseline was significantly higher in cases than in controls (median 65.8, range 27.2-134.5 U/mL vs. median 22.2, range 8.4-63.1 U/mL, P=0.001). In the univariate logistic regression analysis, a higher sCD30 (≥30.2 U/mL) was significantly associated with ATL development (odds ratio 7.88 and the 95% confidence intervals 1.35-45.8, P = 0.02). Among cases, sCD30 concentration tended to increase at the time of diagnosis of aggressive-type ATL, but the concentration was stable in those developing the smoldering-type. This suggests that sCD30 may serve as a predictive marker for the onset of aggressive-type ATL in HTLV-1 carriers.

Modest increase in risk of acute coronary syndrome associated with morphine use in cancer patients: a population-based nested case-control study.

PubMed

Lee, Cynthia Wei-Sheng; Muo, Chih-Hsin; Liang, Ji-An; Sung, Fung-Chang; Kao, Chia-Hung

2014-06-01

Morphine is widely used for pain management in cancer patients. Use of heroin, a morphine derivative, is a risk factor for acute coronary syndrome (ACS). This study investigates the risk of ACS associated with morphine use by comparing the incidence of ACS in cancer patients treated with and without morphine. This is a population-based nested case-control study using the Longitudinal Health Insurance Database 2000 in Taiwan. In total, 31,384 patients on the database were diagnosed with cancer without prior history of ACS during 1998-2010. In this cohort, 499 patients subsequently developed ACS and 30,885 patients did not. The 499 patients were designated as the ACS group; controls were selected from the remaining 30,885 patients and matched 3:1 to each case for age, sex, year of cancer diagnosis, and index year. Logistic regression was used to estimate the odds ratios and 95% confidence intervals, and the multivariable model was applied to control for age, sex, and Charlson comorbidity score. Cancer patients who received morphine had a 32% higher risk of developing ACS than non-morphine users. This increase in risk was significant when evaluating the overall cancer patients, but non-significant when evaluating any specific cancer type. The risk of ACS increased significantly with increasing morphine dosage (to ≥65 mg/y). Morphine treatment is associated with a modest increase in risk of ACS in patients with malignancy, but this association displays low significance in specific cancer types. Copyright © 2014 Elsevier Ltd. 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

Risk for attempted suicide in children and youths after contact with somatic hospitals: a Danish register based nested case-control study.

PubMed

Christiansen, E; Stenager, E

2012-03-01

A range of studies have found an association between some somatic diseases and increased risk of suicide and attempted suicide. These studies are mostly analyses of adult populations and illnesses related to adulthood. To study the risk of attempted suicide in children and youths with a somatic diagnosis, and to assess a possible association from a somatic perspective. From a cohort of 403 431 individuals (born 1983-89), 3465 children and youths who had attempted suicide were identified. Each case was matched with 20 population controls. 72 765 children and youths constituted the case-control population. All data were obtained from national population registers and analysed in a nested case-control design. Contact of children and youths with a somatic hospital is correlated with increased risk of attempted suicide; the risk peaks in the time immediately after contact. Risk factors were treatment for injury caused by violence, epilepsy, asthma and malformation for males; and spontaneous and medical abortions, treatment for injury caused by violence, epilepsy, asthma, insulin dependent diabetes mellitus and malformation for females. Not all the mentioned diagnoses were significant in the adjusted model. Based on the results of the study a strategy to minimise the risk of attempted suicide among children and youths must be implemented. The strategy should mainly focus on children at high risk-that is, children from families with low socioeconomic status, and children with a psychiatric history, a history of previous suicide attempts and with an unstable somatic disease subsequently causing many admissions.

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

Employment history indicators and mortality in a nested case-control study from the Spanish WORKing life social security (WORKss) cohort

PubMed Central

2017-01-01

Employment has transitioned from stable to more flexible schemes. Little is known about the effects of dynamic working lives and mortality. We examined the association of employment, unemployment and inactivity on mortality among workers born in 1926–1988, in a nested case-control study of workers from the Spanish WORKss cohort. Cases were all deaths that occurred during 2004–2013 and controls were living persons, matched for sex and age at the time the case occurred. We had information on employment from 1981 to 2013. Logistic regression was used to measure the associations between the 3 employment history indicators separately by sex. There were 53,989 cases and an equal number of controls (n = 107,978). More than 16 years employed showed a protective effect against mortality in women (OR = 0.88, 95%CI: 0.81, 0.94) and men (OR = 0.76, 95%CI: 0.70, 0.79). The number of spells and time in unemployment and inactivity were significantly related to mortality in men, but not women. Sensitivity analyses by labor relationship showed stronger associations of unemployment (OR = 1.42, 95%CI: 1.13, 1.78) and inactivity (OR = 1.34; 95%CI: 1.09, 1.65) for temporary workers. Employment gaps are detrimental to health and have worse effects if the gaps occur without unemployment benefits or after temporary contracts. These results may drive improvement of labor and social policies that protect workers against the potential negative effects of dynamic work lives. PMID:28570614

Alcohol and Difficulty Conceiving in the SUN Cohort: A Nested Case-Control Study.

PubMed

Lopez-del Burgo, Cristina; Gea, Alfredo; de Irala, Jokin; Martínez-González, Miguel A; Chavarro, Jorge E; Toledo, Estefania

2015-07-27

The role of alcohol on fertility remains unclear. We aimed to investigate the association between alcohol and specific alcoholic beverages consumption and the risk of difficulty getting pregnant. We used a case-control study nested within the Seguimiento Universidad de Navarra (SUN) cohort, a prospective, dynamic and multipurpose cohort of 21,705 Spanish university graduates, followed biennially with mailed questionnaires. We identified 686 case-control pairs, matched for age and time in the cohort. Cases were women reporting difficulty getting pregnant. Controls did not consult due to difficulty conceiving and had at least one child during follow-up. After adjustment for potential confounders, we found no association between self-reported difficulty getting pregnant and the number of alcoholic beverages consumed per week, (Odds Ratio [OR] > 5 drinks/week vs. none = 1.04, 95% Confidence Interval [CI] = 0.72-1.51). No association between types of alcoholic beverage and difficulty conceiving (OR > 5 drinks of wine/week vs. none = 1.16, 95% CI = 0.72-1.88; OR > 5 drinks of beer/week vs. none = 1.06, 95% CI = 0.82-1.37; OR > 5 drinks of spirits/week vs. none = 1.24, 95% CI = 0.84-1.64) was observed. In conclusion, we found no association between alcohol intake and risk of consulting a physician due to difficulty conceiving. More studies are needed to clearly elucidate the effects of alcohol intake on women's fertility. In the meantime, recommendations about alcohol intake to couples trying to conceive have to be given cautiously.

Alcohol and Difficulty Conceiving in the SUN Cohort: A Nested Case-Control Study

PubMed Central

Lopez-del Burgo, Cristina; Gea, Alfredo; de Irala, Jokin; Martínez-González, Miguel A.; Chavarro, Jorge E.; Toledo, Estefania

2015-01-01

The role of alcohol on fertility remains unclear. We aimed to investigate the association between alcohol and specific alcoholic beverages consumption and the risk of difficulty getting pregnant. We used a case-control study nested within the Seguimiento Universidad de Navarra (SUN) cohort, a prospective, dynamic and multipurpose cohort of 21,705 Spanish university graduates, followed biennially with mailed questionnaires. We identified 686 case-control pairs, matched for age and time in the cohort. Cases were women reporting difficulty getting pregnant. Controls did not consult due to difficulty conceiving and had at least one child during follow-up. After adjustment for potential confounders, we found no association between self-reported difficulty getting pregnant and the number of alcoholic beverages consumed per week, (Odds Ratio [OR] > 5 drinks/week vs. none = 1.04, 95% Confidence Interval [CI] = 0.72–1.51). No association between types of alcoholic beverage and difficulty conceiving (OR > 5 drinks of wine/week vs. none = 1.16, 95% CI = 0.72–1.88; OR > 5 drinks of beer/week vs. none = 1.06, 95% CI = 0.82–1.37; OR > 5 drinks of spirits/week vs. none = 1.24, 95% CI = 0.84–1.64) was observed. In conclusion, we found no association between alcohol intake and risk of consulting a physician due to difficulty conceiving. More studies are needed to clearly elucidate the effects of alcohol intake on women’s fertility. In the meantime, recommendations about alcohol intake to couples trying to conceive have to be given cautiously. PMID:26225997

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.

Latitudinal variation in avian incubation attentiveness and a test of the food limitation hypothesis

USGS Publications Warehouse

Chalfoun, A.D.; Martin, T.E.

2007-01-01

Avian incubation attentiveness has important fitness consequences through its influence on the number and quality of hatched young and energetic costs imposed on parents. Nest attentiveness is highly variable across species and geographical regions. We reviewed the literature and found a worldwide pattern that nest attentiveness of passerines is generally lower in south temperate and tropical regions than in north temperate regions. We also conducted a food manipulation experiment to assess the extent to which nest attentiveness may reflect proximate responses versus an evolved behaviour. We used the karoo prinia, Prinia maculosa, in South Africa, which has very low nest attentiveness (???49%) compared with that of many passerine birds. We provided supplemental food during early incubation to experimental females and compared nest attentiveness and on- and off-bout lengths of experimental and paired control females.??Nest attentiveness of females at food-provisioned nests was significantly higher than that of control females (57% versus 49%). Food-supplemented females also spent significantly less time off the nest than did control females, whereas mean on-bout lengths did not differ. However, mean nest attentiveness of food-provisioned females was still substantially below that of other similar bird species worldwide. Food can be an important proximate influence on parental care behaviour, but proximate influences of food do not explain broad latitudinal patterns of attentiveness. ?? 2007 The Association for the Study of Animal Behaviour.

Baseline Serum Estradiol and Fracture Reduction During Treatment With Hormone Therapy: The Women’s Health Initiative Randomized Trial

PubMed Central

Cauley, Jane A.; LaCroix, Andrea Z.; Robbins, John A.; Larson, Joseph; Wallace, Robert; Wactawski-Wende, Jean; Chen, Zhao; Bauer, Douglas C.; Cummings, Steven R.; Jackson, Rebecca

2009-01-01

Purpose To test the hypothesis that the reduction in fractures with hormone therapy (HT) is greater in women with lower estradiol levels. Methods We conducted a nested case-control study within the Women’s Health Initiative HT Trials. The sample included 231 hip fracture case-control pairs and a random sample of 519 all fracture case-control pairs. Cases and controls were matched for age, ethnicity, randomization date, fracture history and hysterectomy status. Hormones were measured prior to randomization. Incident cases of fracture identified over an average follow-up of 6.53 years. Results There was no evidence that the effect of HT on fracture differed by baseline estradiol (E2) or sex hormone binding globulin (SHBG). Across all quartiles of E2 and SHBG, women randomized to HT had about a 50% lower risk of fracture including hip fracture, compared to placebo. Conclusion The effect of HT on fracture reduction is independent of estradiol and SHBG levels. PMID:19436934

Sarcoidosis diagnosed after September 11, 2001, among adults exposed to the World Trade Center disaster.

PubMed

Jordan, Hannah T; Stellman, Steven D; Prezant, David; Teirstein, Alvin; Osahan, Sukhminder S; Cone, James E

2011-09-01

Explore relationships between World Trade Center (WTC) exposures and sarcoidosis. Sarcoidosis has been reported after exposure to the WTC disaster. We ascertained biopsy-proven post-9/11 sarcoidosis among WTC Health Registry enrollees. Cases diagnosed after Registry enrollment were included in a nested case-control study. Controls were matched to cases on age, sex, race or ethnicity, and eligibility group (eg, rescue or recovery worker). We identified 43 cases of post-9/11 sarcoidosis. Twenty-eight incident cases and 109 controls were included in the case-control analysis. Working on the WTC debris pile was associated with sarcoidosis (odds ratio 9.1, 95% confidence interval 1.1 to 74.0), but WTC dust cloud exposure was not (odds ratio 1.0, 95% confidence interval 0.4 to 2.8). Working on the WTC debris pile was associated with an elevated risk of post-9/11 sarcoidosis. Occupationally exposed workers may be at increased risk. (C)2011The American College of Occupational and Environmental Medicine

Impact of nesting material on mouse body temperature and physiology.

PubMed

Gaskill, Brianna N; Gordon, Christopher J; Pajor, Edmond A; Lucas, Jeffrey R; Davis, Jerry K; Garner, Joseph P

2013-02-17

In laboratories, mice are housed at 20-24 °C, which is below their lower critical temperature (≈30 °C). Thus, mice are potentially cold stressed, which can alter metabolism, immune function, and reproduction. These physiological changes reflect impaired wellbeing, and affect scientific outcomes. We hypothesized that nesting material would allow mice to alleviate cold stress by controlling their thermal microenvironment, thus insulating them, reducing heat loss and thermogenic processes. Naïve C57BL/6, CD-1, and BALB/c mice (24 male and 24 female/strain in groups of 3) were housed in standard cages at 20 °C either with or without 8 g nesting material for 4 weeks. Core body temperature was followed using intraperitoneal radio telemetry. The thermal properties of the nests were assessed using a thermal imaging camera, and related to nest quality. Higher scoring nests were negatively correlated with the mean radiated temperature and were thus more insulating. No effects of nesting material on body temperature were found. CD-1 mice with nesting material had higher end body weights than controls. No effect was seen in the other two strains. Mice with the telemetry implant had larger spleens than controls, possibly indicating an immune response to the implant or low level infection from the surgery. BALB/c mice express less mRNA for the UCP1 protein than mice without nesting material. This indicates that BALB/c's with nesting material do not utilize their brown fat to create heat as readily as controls. Nests can alleviate thermal discomfort by decreasing the amount of radiated heat and reduce the need for non-shivering thermogenesis. However, different strains appear to use different behavioral (through different primary modes of behavioral thermoregulation) and physiological strategies (utilizing thermogenesis to different degrees) to maintain a constant body temperature under cool standard laboratory ambient temperatures. Copyright © 2013 Elsevier Inc. All rights reserved.

Effects of industrial and investigator disturbance on Arctic-nesting geese

USGS Publications Warehouse

Meixell, Brandt W.; Flint, Paul L.

2017-01-01

Oil and gas development on the Arctic Coastal Plain (ACP) of Alaska, USA may have effects on Arctic-nesting birds. To estimate effects of industrial activity and investigator disturbance on avian productivity, we monitored nests of greater white-fronted geese (Anser albifrons) with digital cameras and periodic nest visits during 2013–2014 at 2 sites on the ACP. A disturbed site was adjacent to human-made infrastructure and industrial clean-up activities initiated at the onset of the study and a control site was >2 km from sources of industrial disturbance. We assessed variation in estimates of incubation constancy, nest survival, and predator behavior relative to site, year, and distance from industrial activity using nest photographs obtained at 1-minute intervals. We compared analysis of hourly nest survival informed by intensive monitoring with cameras to analysis of daily nest survival informed by traditional nest visit data obtained at intervals of 5–7 days to assess how method and time scale of sampling affect ecological inference. Geese in both sites exhibited high levels of nest attendance and initiated incubation breaks less than once per day. Observer-caused incubation breaks associated with nest visits ( = 37.8 min) were longer than other types of incubation breaks ( = 8.7 min), demonstrating a differential response by nesting geese to direct human encroachment versus indirect vehicular and aircraft traffic. During both years, geese were absent from nests more frequently in the disturbed ( = 0.9 breaks/day) than control ( = 0.6 breaks/day) site, and this break frequency was slightly higher for nests closer to industrial activity. In the year with high rates of depredation, nest survival was positively related to distance from industrial activity and abandoned infrastructure, consistent with predictions of industry-caused effects. This relationship, however, was not evident in the year with reduced predation pressure, likely because of annual variation in arctic fox (Vulpes lagopus) behavior. Analysis of nest survival probability informed by camera data allowed for detection of detailed patterns of variation that were not supported when using only visit data for the same nests. Observer visits were responsible for reductions of 7–35% in nest survival probability, highlighting the importance of minimizing, and controlling for, observer effects in studies of avian productivity. Indirect vehicular and aircraft disturbance posed less risk to nest survival than direct encroachment by observers at nest sites. Therefore, effects of industrial activities on avian productivity in the Arctic can be minimized through practices that limit direct encounters with nests. 

Association of benzodiazepine and Z-drug use with the risk of hospitalisation for fall-related injuries among older people: a nationwide nested case-control study in Taiwan.

PubMed

Yu, Nan-Wen; Chen, Pei-Jung; Tsai, Hui-Ju; Huang, Chih-Wan; Chiu, Yu-Wen; Tsay, Wen-Ing; Hsu, Jui; Chang, Chia-Ming

2017-07-11

Non-benzodiazepine hypnotics (Z-drugs) are advocated to be safer than benzodiazepines (BZDs). This study comprehensively investigated the association of BZD and Z-drug usage with the risk of hospitalisation for fall-related injuries in older people. This study used the Taiwan National Health Insurance Database with a nested matched case-control design. We identified 2238 elderly patients who had been hospitalised for fall-related injuries between 2003 and 2012. They were individually matched (1:4) with a comparison group by age, sex, and index year. Conditional logistic regression was used to determine independent effects of drug characteristics (type of exposure, dosage, half-life, and polypharmacy) on older people. Older people hospitalisation for fall-related injuries were significantly associated with current use of BZDs (adjusted odds ratio [AOR] = 1.32, 95% confidential interval [CI] = 1.17-1.50) and Z-drugs (AOR = 1.24, 95%CI = 1.05-1.48). At all dose levels of BZDs, high dose levels of Z-drugs, long-acting BZD, and short-acting BZD use were all significantly increased the risk of fall-related injuries requiring hospitalisation. Polypharmacy, the use of two or more kinds of BZDs, one kind of BZD plus Z-drugs and two or more kinds of BZDs plus Z-drugs, also significantly increased the risk (AOR = 1.61, 95% CI = 1.38-1.89; AOR = 1.65, 95% CI = 1.08-2.50, and AOR = 1.58, 95% CI = 1.21-2.07). Different dose levels and half-lives of BZDs, a high dose of Z-drugs, and polypharmacy with BZDs and Z-drugs were associated with an increased risk of fall-related injury requiring hospitalisation in older people. Physicians should balance the risks and benefits when prescribing these drug regimens to older people considering the risk of falls.

Nest survival of American Coots relative to grazing, burning, and water depths

USGS Publications Warehouse

Austin, Jane E.; Buhl, Deborah A.

2011-01-01

Water and emergent vegetation are key features influencing nest site selection and success for many marsh-nesting waterbirds. Wetland management practices such as grazing, burning, and water-level manipulations directly affect these features and can influence nest survival. We used model selection and before-after-control-impact approaches to evaluate the effects of water depth and four common land-management practices or treatments, i.e., summer grazing, fall grazing, fall burning, and idle (no active treatment) on nest survival of American coots (Fulica americana) nesting at Grays Lake, a large montane wetland in southeast Idaho. The best model included the variables year × treatment, and quadratic functions of date, water depth, and nest age; height of vegetation at the nest did not improve the best model. However, results from the before-after-control-impact analysis indicate that management practices affected nest success via vegetation and involved interactions of hydrology, residual vegetation, and habitat composition. Nest success in idled fields changed little between pre- and post-treatment periods, whereas nest success declined in fields that were grazed or burned, with the most dramatic declines the year following treatments. The importance of water depth may be amplified in this wetland system because of rapid water-level withdrawal during the nesting season. Water and land-use values for area ranchers, management for nesting waterbirds, and long-term wetland function are important considerations in management of water levels and vegetation.

An exploratory randomised controlled trial of a premises-level intervention to reduce alcohol-related harm including violence in the United Kingdom

PubMed Central

2012-01-01

Background To assess the feasibility of a randomised controlled trial of a licensed premises intervention to reduce severe intoxication and disorder; to establish effect sizes and identify appropriate approaches to the development and maintenance of a rigorous research design and intervention implementation. Methods An exploratory two-armed parallel randomised controlled trial with a nested process evaluation. An audit of risk factors and a tailored action plan for high risk premises, with three month follow up audit and feedback. Thirty-two premises that had experienced at least one assault in the year prior to the intervention were recruited, match paired and randomly allocated to control or intervention group. Police violence data and data from a street survey of study premises’ customers, including measures of breath alcohol concentration and surveyor rated customer intoxication, were used to assess effect sizes for a future definitive trial. A nested process evaluation explored implementation barriers and the fidelity of the intervention with key stakeholders and senior staff in intervention premises using semi-structured interviews. Results The process evaluation indicated implementation barriers and low fidelity, with a reluctance to implement the intervention and to submit to a formal risk audit. Power calculations suggest the intervention effect on violence and subjective intoxication would be raised to significance with a study size of 517 premises. Conclusions It is methodologically feasible to conduct randomised controlled trials where licensed premises are the unit of allocation. However, lack of enthusiasm in senior premises staff indicates the need for intervention enforcement, rather than voluntary agreements, and on-going strategies to promote sustainability. Trial registration UKCRN 7090; ISRCTN: 80875696 PMID:22676069

Hospital-treated mental and behavioral disorders and risk of Alzheimer's disease: A nationwide nested case-control study.

PubMed

Tapiainen, V; Hartikainen, S; Taipale, H; Tiihonen, J; Tolppanen, A-M

2017-06-01

Studies investigating psychiatric disorders as Alzheimer's disease (AD) risk factors have yielded heterogeneous findings. Differences in time windows between the exposure and outcome could be one explanation. We examined whether (1) mental and behavioral disorders in general or (2) specific mental and behavioral disorder categories increase the risk of AD and (3) how the width of the time window between the exposure and outcome affects the results. A nationwide nested case-control study of all Finnish clinically verified AD cases, alive in 2005 and their age, sex and region of residence matched controls (n of case-control pairs 27,948). History of hospital-treated mental and behavioral disorders was available since 1972. Altogether 6.9% (n=1932) of the AD cases and 6.4% (n=1784) of controls had a history of any mental and behavioral disorder. Having any mental and behavioral disorder (adjusted OR=1.07, 95% CI=1.00-1.16) or depression/other mood disorder (adjusted OR=1.17, 95% CI=1.05-1.30) were associated with higher risk of AD with 5-year time window but not with 10-year time window (adjusted OR, 95% CI 0.99, 0.91-1.08 for any disorder and 1.08, 0.96-1.23 for depression). The associations between mental and behavioral disorders and AD were modest and dependent on the time window. Therefore, some of the disorders may represent misdiagnosed prodromal symptoms of AD, which underlines the importance of proper differential diagnostics among older persons. These findings also highlight the importance of appropriate time window in psychiatric and neuroepidemiology research. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

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.

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

Responses of cavity-nesting birds to stand-replacement fire and salvage logging in ponderosa pine/Douglas-fir forests of southwestern Idaho

Treesearch

Victoria A. Saab; Jonathan G. Dudley

1998-01-01

From 1994 to 1996, researchers monitored 695 nests of nine cavity-nesting bird species and measured vegetation at nest sites and at 90 randomly located sites in burned ponderosa pine forests of southwestern Idaho. Site treatments included two types of salvage logging, and unlogged controls. All bird species selected nest sites with higher tree densities, larger...

Factors influencing depredation of artificial duck nests

USGS Publications Warehouse

Esler, Daniel N.; Grand, James B.

1993-01-01

Because artificial nests can facilitate controlled experiments of nest success, we used them to assess whether human visitation, nest density, vegetation structure, and proximity to habitat edge could affect depredation of duck nests on Yukon Flats National Wildlife Refuge, Alaska. More (P < 0.01) nests in a plot visited daily (100%) were depredated than those in plots visited at intervals of 7 (40%), 14 (35%), or 28 days (45%). More (P < 0.01) nests were depredated in a plot with 10 nests/ha (95%) than nests in a plot of a lower density (2/ha; 40%). Vegetation height, vegetation density, distance to a wetland, distance to forest edge, or distance to the nearest ecotone did not differ (P > 0.05) between depredated and undisturbed nests. We suggest that daily visitation of duck nests increases depredation, but longer intervals, typical of most nest studies, do not. High nesting densities, which could occur when flooding limits nesting habitat, may result in higher depredation rates.

Trap Nesting Wasps and Bees in Agriculture: A Comparison of Sown Wildflower and Fallow Plots in Florida

PubMed Central

Smithers, Cherice; Irvin, Allyn; Stanley-Stahr, Cory; Daniels, Jaret C.; Ellis, James D.

2017-01-01

Wildflower strip plantings in intensive agricultural systems have become a widespread tool for promoting pollination services and biological conservation because of their use by wasps and bees. Many of the trap-nesting wasps are important predators of common crop pests, and cavity-nesting bees that utilize trap-nests are important pollinators for native plants and many crops. The impact of wildflower strips on the nesting frequency of trap-nesting wasps or bees within localized areas has not been thoroughly investigated. Trap-nests made of bamboo reeds (Bambusa sp.) were placed adjacent to eight 0.1 ha wildflower plots and paired fallow areas (control plots) to determine if wildflower strips encourage the nesting of wasps and bees. From August 2014 to November 2015, occupied reeds were gathered and adults were collected as they emerged from the trap-nests. Treatment (wildflower or fallow plots) did not impact the number of occupied reeds or species richness of trap-nesting wasps using the occupied reeds. The wasps Pachodynerus erynnis, Euodynerus megaera, Parancistrocerus pedestris, and Isodontia spp. were the most common trap-nesting species collected. Less than 2% of the occupied reeds contained bees, and all were from the genus Megachile. The nesting wasp and bee species demonstrated preferences for reeds with certain inside diameters (IDs). The narrow range of ID preferences exhibited by each bee/wasp may provide opportunities to take advantage of their natural histories for biological control and/or pollination purposes. PMID:28994726

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.

There Is No Difference in IQ between Suicide and Non-Suicide Psychiatric Patients: A Retrospective Case-Control Study.

PubMed

Park, Sung-Jin; Yi, Kikyoung; Lee, Joon Deuk; Hong, Jin Pyo

2015-07-01

The goal of this study was to examine the association between IQ and suicide in psychiatric patients. We conducted a nested case-control study using data obtained from psychiatric patients affiliated with a general hospital in Seoul, Korea. In a one-to-two ratio the psychiatric patients who died of suicide (Suicide Group; n=35) were matched to those who didn't (Non-suicide Group; n=70) by age, gender, psychiatric diagnosis and approximate time of first treatment. IQ was measured using the Korean version of the Wechsler Adult Intelligence Scale-Revised. There were no significant differences in any type of IQ between suicide patients and non-suicide patients. Logistic regression showed no evidence of an association between IQ and suicide. These results do not support the existence of an association between IQ and suicide.

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.

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 .

Fatal injuries in the slums of Nairobi and their risk factors: results from a matched case-control study.

PubMed

Ziraba, Abdhalah Kasiira; Kyobutungi, Catherine; Zulu, Eliya Msiyaphazi

2011-06-01

Injuries contribute significantly to the rising morbidity and mortality attributable to non-communicable diseases in the developing world. Unfortunately, active injury surveillance is lacking in many developing countries, including Kenya. This study aims to describe and identify causes of and risk factors for fatal injuries in two slums in Nairobi city using a demographic surveillance system framework. The causes of death are determined using verbal autopsies. We used a nested case-control study design with all deaths from injuries between 2003 and 2005 as cases. Two controls were randomly selected from the non-injury deaths over the same period and individually matched to each case on age and sex. We used conditional logistic regression modeling to identity individual- and community-level factors associated with fatal injuries. Intentional injuries accounted for about 51% and unintentional injuries accounted for 49% of all injuries. Homicides accounted for 91% of intentional injuries and 47% of all injury-related deaths. Firearms (23%) and road traffic crashes (22%) were the leading single causes of deaths due to injuries. About 15% of injuries were due to substance intoxication, particularly alcohol, which in this community comes from illicit brews and is at times contaminated with methanol. Results suggest that in the pervasively unsafe and insecure environment that characterizes the urban slums, ethnicity, residence, and area level factors contribute significantly to the risk of injury-related mortality.

Bird nesting and droppings control on highway structures.

DOT National Transportation Integrated Search

2010-10-01

This report provides a comprehensive literature survey of permanent and temporary deterrents to nesting and roosting, a : discussion of risks to human health and safety from exposure to bird nests and droppings and recommended protective measures, : ...

Assessing Student Achievement in Large-Scale Educational Programs Using Hierarchical Propensity Scores

ERIC Educational Resources Information Center

Vaughan, Angela L.; Lalonde, Trent L.; Jenkins-Guarnieri, Michael A.

2014-01-01

Many researchers assessing the efficacy of educational programs face challenges due to issues with non-randomization and the likelihood of dependence between nested subjects. The purpose of the study was to demonstrate a rigorous research methodology using a hierarchical propensity score matching method that can be utilized in contexts where…

Biomarkers and bacterial pneumonia risk in patients with treated HIV infection: a case-control study.

PubMed

Bjerk, Sonja M; Baker, Jason V; Emery, Sean; Neuhaus, Jacqueline; Angus, Brian; Gordin, Fred M; Pett, Sarah L; Stephan, Christoph; Kunisaki, Ken M

2013-01-01

Despite advances in HIV treatment, bacterial pneumonia continues to cause considerable morbidity and mortality in patients with HIV infection. Studies of biomarker associations with bacterial pneumonia risk in treated HIV-infected patients do not currently exist. We performed a nested, matched, case-control study among participants randomized to continuous combination antiretroviral therapy (cART) in the Strategies for Management of Antiretroviral Therapy trial. Patients who developed bacterial pneumonia (cases) and patients without bacterial pneumonia (controls) were matched 1∶1 on clinical center, smoking status, age, and baseline cART use. Baseline levels of Club Cell Secretory Protein 16 (CC16), Surfactant Protein D (SP-D), C-reactive protein (hsCRP), interleukin-6 (IL-6), and d-dimer were compared between cases and controls. Cases (n = 72) and controls (n = 72) were 25.7% female, 51.4% black, 65.3% current smokers, 9.7% diabetic, 36.1% co-infected with Hepatitis B/C, and 75.0% were on cART at baseline. Median (IQR) age was 45 (41, 51) years with CD4+ count of 553 (436, 690) cells/mm(3). Baseline CC16 and SP-D were similar between cases and controls, but hsCRP was significantly higher in cases than controls (2.94 µg/mL in cases vs. 1.93 µg/mL in controls; p = 0.02). IL-6 and d-dimer levels were also higher in cases compared to controls, though differences were not statistically significant (p-value 0.06 and 0.10, respectively). In patients with cART-treated HIV infection, higher levels of systemic inflammatory markers were associated with increased bacterial pneumonia risk, while two pulmonary-specific inflammatory biomarkers, CC16 and SP-D, were not associated with bacterial pneumonia risk.

Honey Bee Inhibitory Signaling Is Tuned to Threat Severity and Can Act as a Colony Alarm Signal

PubMed Central

Li, Xinyu; Liu, Xiwen; Wang, Chao; Li, Jianjun

2016-01-01

Alarm communication is a key adaptation that helps social groups resist predation and rally defenses. In Asia, the world’s largest hornet, Vespa mandarinia, and the smaller hornet, Vespa velutina, prey upon foragers and nests of the Asian honey bee, Apis cerana. We attacked foragers and colony nest entrances with these predators and provide the first evidence, in social insects, of an alarm signal that encodes graded danger and attack context. We show that, like Apis mellifera, A. cerana possesses a vibrational “stop signal,” which can be triggered by predator attacks upon foragers and inhibits waggle dancing. Large hornet attacks were more dangerous and resulted in higher bee mortality. Per attack at the colony level, large hornets elicited more stop signals than small hornets. Unexpectedly, stop signals elicited by large hornets (SS large hornet) had a significantly higher vibrational fundamental frequency than those elicited by small hornets (SS small hornet) and were more effective at inhibiting waggle dancing. Stop signals resulting from attacks upon the nest entrance (SS nest) were produced by foragers and guards and were significantly longer in pulse duration than stop signals elicited by attacks upon foragers (SS forager). Unlike SS forager, SS nest were targeted at dancing and non-dancing foragers and had the common effect, tuned to hornet threat level, of inhibiting bee departures from the safe interior of the nest. Meanwhile, nest defenders were triggered by the bee alarm pheromone and live hornet presence to heat-ball the hornet. In A. cerana, sophisticated recruitment communication that encodes food location, the waggle dance, is therefore matched with an inhibitory/alarm signal that encodes information about the context of danger and its threat level. PMID:27014876

Honey Bee Inhibitory Signaling Is Tuned to Threat Severity and Can Act as a Colony Alarm Signal.

PubMed

Tan, Ken; Dong, Shihao; Li, Xinyu; Liu, Xiwen; Wang, Chao; Li, Jianjun; Nieh, James C

2016-03-01

Alarm communication is a key adaptation that helps social groups resist predation and rally defenses. In Asia, the world's largest hornet, Vespa mandarinia, and the smaller hornet, Vespa velutina, prey upon foragers and nests of the Asian honey bee, Apis cerana. We attacked foragers and colony nest entrances with these predators and provide the first evidence, in social insects, of an alarm signal that encodes graded danger and attack context. We show that, like Apis mellifera, A. cerana possesses a vibrational "stop signal," which can be triggered by predator attacks upon foragers and inhibits waggle dancing. Large hornet attacks were more dangerous and resulted in higher bee mortality. Per attack at the colony level, large hornets elicited more stop signals than small hornets. Unexpectedly, stop signals elicited by large hornets (SS large hornet) had a significantly higher vibrational fundamental frequency than those elicited by small hornets (SS small hornet) and were more effective at inhibiting waggle dancing. Stop signals resulting from attacks upon the nest entrance (SS nest) were produced by foragers and guards and were significantly longer in pulse duration than stop signals elicited by attacks upon foragers (SS forager). Unlike SS forager, SS nest were targeted at dancing and non-dancing foragers and had the common effect, tuned to hornet threat level, of inhibiting bee departures from the safe interior of the nest. Meanwhile, nest defenders were triggered by the bee alarm pheromone and live hornet presence to heat-ball the hornet. In A. cerana, sophisticated recruitment communication that encodes food location, the waggle dance, is therefore matched with an inhibitory/alarm signal that encodes information about the context of danger and its threat level.

Cancer complicating systemic lupus erythematosus--a dichotomy emerging from a nested case-control study.

PubMed

Dey, D; Kenu, E; Isenberg, D A

2013-08-01

We determined whether any individual cancers are increased or decreased in a cohort of 595 patients with systemic lupus erythematosus (SLE) followed for up to 32 years at the University College London Hospitals Lupus Clinic, looking for any associated clinical or serological factors and the prognosis after cancer diagnosis. We undertook a careful retrospective review of the medical records and identified all individuals diagnosed with cancer. For controls, we selected three other patients in the cohort who had not developed cancer, carefully matched for age, sex, ethnicity and disease duration, to determine if any obvious differences emerged in a nested case-control design. Thirty-three patients developed cancer after being diagnosed with SLE. There was a statistically insignificant small increase in overall cancer risk, standardized incidence ratios (SIRs) 1.05 (95% CI 0.52-1.58) and increased SIRs for cervical, prostate, anal and pancreatic cancers and reduction in breast cancer SIRs. Haematological and musculoskeletal manifestations, anticardiolipin and antithyroid globulin antibodies were found to be positively associated with cancer risk in multivariate analysis. There was no drug, dose or duration was associated with cancer risk. There was a reduction in survival with a cancer fatality rate of 84.2% (p < 0.0001). We found a very small but statistically insignificant increased cancer risk with reduction in survival. Whereas some cancers appear to be more common in SLE, notably prostate and cervical cancer, others, particularly breast cancer, are less frequent. Multiple clinical and serological factors are involved in the increased risk of malignancy in SLE. No drug dose or duration effect was identified.

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

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.

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.

Cardiac glycosides use and the risk of lung cancer: a nested case-control study.

PubMed

Couraud, Sébastien; Azoulay, Laurent; Dell'Aniello, Sophie; Suissa, Samy

2014-08-08

Two studies have reported statistically significant associations between the use of cardiac glycosides (CGs) and an increased risk of lung cancer. However, these studies had a number of methodological limitations. Thus, the objective of this study was to assess this association in a large population-based cohort of patients. We used the United Kingdom Clinical Practice Research Datalink (CPRD) to identify a cohort of patients, at least 40 years of age, newly-diagnosed with heart failure, or supra-ventricular arrhythmia. A nested case-control analysis was conducted where each incident case of lung cancer identified during follow-up was randomly matched with up to 10 controls. Exposure to CGs was assessed in terms of ever use, cumulative duration of use and cumulative dose. Rate ratios (RRs) with 95% confidence intervals (CIs) were estimated using conditional logistic regression after adjusting for potential confounders. A total of 129,002 patients were included, and followed for a mean (SD) of 4.7 (3.8) years. During follow-up, 1237 patients were newly-diagnosed with lung cancer. Overall, ever use of CGs was not associated with an increased risk of lung cancer when compared to never use (RR = 1.09, 95% CI: 0.94-1.26). In addition, no dose-response relationship was observed in terms of cumulative duration of use and cumulative dose with all RRs around the null value across quartile categories. The results of this large population-based study indicate that the use of CGs is not associated with an increased risk of lung cancer.

NO2, as a marker of air pollution, and recurrent wheezing in children: a nested case-control study within the BAMSE birth cohort

PubMed Central

Emenius, G; Pershagen, G; Berglind, N; Kwon, H; Lewne, M; Nordvall, S; Wickman, M

2003-01-01

Aims: To investigate the association between air pollution, including with NO2, and recurrent wheezing during the first two years of life. Methods: A birth cohort (BAMSE) comprised 4089 children, for whom information on exposures, symptoms, and diseases was available from parental questionnaires at ages 2 months, and 1 and 2 years. NO2 was measured during four weeks in and outside the dwellings of children with recurrent wheezing and two age matched controls, in a nested case-control study (540 children). Results: Conditional logistic regression showed an OR of 1.60 (95% CI 0.78 to 3.26) among children in the highest quartile of outdoor NO2 exposure in relation to those in the lowest quartile, adjusted for potential confounders. The corresponding OR for indoor NO2 was 1.51 (95% CI 0.81 to 2.82). An interaction with environmental tobacco smoke (ETS) was indicated with an OR of 3.10 (95% CI 1.32 to 7.30) among children exposed to the highest quartile of indoor NO2 and ETS. The association between NO2 and recurrent wheezing appeared stronger in children who did not fulfil the criteria for recurrent wheezing until their second year. Conclusions: Although the odds of increased recurrent wheezing are not statistically significantly different from one, results suggest that exposure to air pollution including NO2, particularly in combination with exposure to ETS, increases the risk of recurrent wheezing in children. PMID:14573719

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.

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.

Cancer risk in relation to serum copper levels.

PubMed

Coates, R J; Weiss, N S; Daling, J R; Rettmer, R L; Warnick, G R

1989-08-01

A nested, matched case-control study was conducted to assess the relationship between serum levels of copper and the subsequent risk of cancer. One hundred thirty-three cases of cancer were identified during 1974-1984 among 5000 members of a northwest Washington State employee cohort from whom serum specimens had been previously obtained and stored. Two hundred forty-one controls were selected at random from the cohort and were matched to the cases on the basis of age, sex, race, and date of blood draw. Serum copper levels were measured by atomic absorption spectrometry. Risk of a subsequent diagnosis of cancer was positively associated with serum copper levels, but only among those cases diagnosed within 4 years of the time the serum specimens were collected. Among cases diagnosed more than 4 years after specimen collection, there was no consistent association between serum copper levels and risk. Adjustment for age, sex, race, occupational status, cigarette smoking, family history of cancer, alcohol consumption, and, among females, use of exogenous hormones had no appreciable effect on these relationships. The findings suggest that the presence of cancer may increase serum copper levels several years prior to its diagnosis. They are less supportive of the hypothesis that serum copper levels affect cancer risk.

Development of a broadly reactive nested reverse transcription-PCR assay to detect murine noroviruses, and investigation of the prevalence of murine noroviruses in laboratory mice in Japan.

PubMed

Kitajima, Masaaki; Oka, Tomoichiro; Tohya, Yukinobu; Katayama, Hiroyuki; Takeda, Naokazu; Katayama, Kazuhiko

2009-09-01

A broadly reactive nested RT-PCR assay to detect MNV was developed and subsequently used to investigate the prevalence of MNV in laboratory mice in Japan. MNV were detected in 8 (22%) of 37 murine stool specimens by second-round PCR, although no positive band was obtained from any specimen by first-round PCR. Genetic analysis of the second round PCR products showed that MNV sequences detected in this study were closely matched (97.2 approximately 99.1%) to that of MNV-3 (DQ223042). This is the first report demonstrating the prevalence of MNV in Japan.

Risk of severe acute liver injury among patients with brain cancer treated with temozolomide: a nested case-control study using the healthcore integrated research database.

PubMed

Desai, Vibha C A; Quinlan, Scott C; Deitz, Anne C; He, Jinghua; Holick, Crystal N; Lanes, Stephan

2017-08-01

Temozolomide (TMZ) is used to treat adult patients with glioblastoma multiforme (GBM). Cases of hepatotoxicity have been reported among patients using TMZ. The objective of the study was to assess the relation, if any, between exposure to TMZ and serious acute liver injury (SALI). We used the HealthCore Integrated Research Database to perform a case-control study nested within a retrospective cohort of adult patients aged 18-100 years with at least two diagnoses of brain cancer anytime between 2006 and 2014. Patients without continuous eligibility or with a SALI diagnosis within 6 months prior to the date of incident brain cancer diagnosis were excluded. Medical records were sought for potential SALI cases and reviewed by two hepatologists. Five controls were selected for each case using incidence density sampling, matched on age and calendar year of index date. The analysis included 61 confirmed SALI cases and 305 selected controls. Exposure to TMZ was classified according to dispensing date and days supply of medication dispensed. We estimated odds ratios using conditional logistic regression models. The odds ratio for any exposure to TMZ was 0.91 (95% CI 0.44-1.91), for recent exposure to TMZ was 0.62 (95% CI 0.21-1.85). There was no increased risk of SALI with increasing duration of exposure to TMZ. When patients with unconfirmed SALI were included in the analysis, results were similar (OR 1.04; 95% CI 0.70-1.54). In conclusion, this study did not find an association between TMZ and SALI risk among patients with brain cancer.

Socioeconomic status and the risk for being diagnosed with spondyloarthritis and chronic pain: a nested case-control study.

PubMed

Jöud, Anna; Petersson, Ingemar F; Jordan, Kelvin P; Löfvendahl, Sofia; Grahn, Birgitta; Englund, Martin

2014-09-01

Socioeconomic status could potentially impact on which type of rheumatic diagnosis a patient receives. We determined whether different socioeconomic status is a risk factor for being diagnosed with spondyloarthritis (SpA) or chronic pain. In a nested case-control study, we identified two sets of adult cases diagnosed with (i) SpA (n = 1,194) and (ii) chronic pain (n = 3,730) during 2010-2012 in Skåne region, Sweden. We randomly sampled controls matched for age and sex. Level of education, marital status, and income were identified in national registers 4 years before inclusion. We also studied health-care utilization, prescribed pharmaceuticals, and work status. We used conditional logistic regressions and included socioeconomic variables and geographic area in the models. Low (odds ratio [OR] 1.69 95 % CI 1.50-1.91) or moderate education (OR 1.43 95 % CI 1.30-1.57), and low (OR 1.40 95 % CI 1.25-1.57) or moderate income (OR 1.24 95 % CI 1.10-1.38) were associated with a chronic pain diagnosis. For a SpA diagnosis, moderate income (OR 1.25 95 % CI 1.04-1.50) was the only significant factor identified. Both case groups had a larger proportion that did not work (P < 0.001), used more health care (P < 0.001), and were more frequently prescribed NSAIDs (P < 0.001) 4 years before diagnosis than controls. We confirmed that lower levels of education and income are associated with a chronic pain diagnosis. This association may reflect a true higher incidence of chronic pain and/or increased consultation propensity for such pain in people with socioeconomic status. We found no such association for SpA.

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.

Nested Case-control Study of Occupational Radiation Exposure and Breast and Esophagus Cancer Risk among Medical Diagnostic X Ray Workers in Jiangsu of China.

PubMed

Wang, Fu-Ru; Fang, Qiao-Qiao; Tang, Wei-Ming; Xu, Xiao-San; Mahapatra, Tanmay; Mahapatra, Sanchita; Liu, Yu-Fei; Yu, Ning-Le; Sun, Quan-Fu

2015-01-01

Medical diagnostic X-ray workers are one occupational group that expose to the long-term low-dose external radiation over their working lifetime, and they may under risk of different cancers. This study aims to determine the relationship between the occupational X-ray radiation exposure and cancer risk among these workers in Jiangsu, China. We conducted Nested case-control study to investigate the occupational X-ray radiation exposure and cancer risk. Data were collected through self-administered questionnaire, which includes but not limits to demographic data, personal behaviors and family history of cancer. Retrospective dose reconstruction was conducted to estimate the cumulative doses of the x-ray workers. Inferential statistics, t-test and 2 tests were used to compare the differences between each group. We used the logistic regression model to calculate the odds ratio (OR) and 95% confidence interval (CI) of cancer by adjusting the age, gender. All 34 breast cancer cases and 45 esophageal cancer cases that detected in a cohort conducted among health workers between 1950~2011 were included in this presented study, and 158 cancer-free controls were selected by frequency-matched (1:2). Our study found that the occupational radiation exposure was associated with a significantly increased cancer risk compared with the control, especially in breast cancer and esophageal cancer (adjusted OR=2.90, 95% CI: 1.19-7.04 for breast cancer; OR=4.19, 95% CI: 1.87-9.38 for esophageal cancer, and OR=3.43, 95% CI: 1.92-6.12 for total cancer, respectively). The occupational X-ray radiation exposure was associated with increasing cancer risk, which indicates that proper intervention and prevention strategies may be needed in order to bring down the occupational cancer risk.

Does physical activity moderate the relationship between depression symptomatology and low back pain? Cohort and co-twin control analyses nested in the longitudinal study of aging Danish twins (LSADT).

PubMed

Hübscher, Markus; Hartvigsen, Jan; Fernandez, Matthew; Christensen, Kaare; Ferreira, Paulo

2016-04-01

To investigate whether depression symptomatology is associated with low back pain (LBP) in twins aged 70+ and whether this effect depends on a person's physical activity (PA) status. This prospective cohort and nested case-control study used a nationally representative sample of twins. Data on depression symptomatology (modified Cambridge Mental Disorders Examination) and self-reported PA were obtained from the Longitudinal Study of Aging Danish Twins using twins without LBP at baseline. Associations between depression symptomatology (highest quartile) at baseline and LBP two years later were investigated using logistic regression analyses adjusted for sex. To examine the moderating effect of PA, we tested its interaction with depression. Associations were analysed using the complete sample of 2446 twins and a matched case-control analysis of 97 twin pairs discordant for LBP at follow-up. Odds ratios (OR) with 95% confidence intervals (CI) were calculated. Using the whole sample, high depression scores were associated with an increased probability of LBP (OR 1.56, 95% CI 1.22-1.99, P ≤ 0.01). There was no statistically significant interaction of light PA and depression symptomatology (OR 0.78, 95% CI 0.46-1.35, P = 0.39) and strenuous PA and depression symptomatology (0.84, 95% CI 0.50-1.41, P = 0.51). The case-control analysis showed similar ORs, although statistically insignificant. High depression symptomatology predicted incident LBP. This effect is supposedly not attributable to genetic or shared environmental factors. Physical activity did not moderate the effect of depression symptomatology on LBP.

The effect of pre-pregnancy hair dye exposure on infant birth weight: a nested case-control study.

PubMed

Jiang, Chao; Hou, Qingzhi; Huang, Yaling; Ye, Juan; Qin, Xiaolian; Zhang, Yu; Meng, Wen; Wang, Qiuyan; Jiang, Yonghua; Zhang, Haiying; Li, Mujun; Mo, Zengnan; Yang, Xiaobo

2018-05-09

Limited evidences were reported about the risk of pre-pregnancy hair dye use or irregular menstruation with abnormal birth weight during pregnancy, and their joint effects were also unknown. The aim of our study was to explore whether the pre-pregnancy exposure of hair dye and irregular menstruation were associated with the risk of abnormal birth weight. We conducted a nested case-control study from a prospective cohort of 6203 pregnant women. Low birth weight study included 315 mother-infant pairs (105 LBW cases and 210 matched controls), and macrosomia study included 381 mother-infant pairs (127 macrosomia cases and 254 matched controls). Meanwhile, lifestyle information including hair dying custom and menstrual history were collected by face-to-face questionnaires and birth outcomes were extracted from the medical records. The logistic regressions models were used to analyze the join effect of irregular menstruation and hair dye use. Pre-pregnancy hair dye use was associated with increased risk of LBW (adjusted OR = 1.71, 95% CI: 1.01-2.92, P = 0.048). Irregular menstruation had high risk of LBW (adjusted OR = 2.79, 95% CI: 1.53-5.09, P = 0.001) and macrosomia (adjusted OR = 1.93, 95% CI: 1.09-3.44, P = 0.023). Additionally, in the LBW study, women who used hair dye with pre-pregnancy BMI < 18.5 kg/m 2 had higher OR than those with only one risk factor (3.07 vs 2.53, P trend  = 0.015), and women with both hair dye use and irregular menstruation also had higher risk than those with only one factor (4.53 vs 2.07, P trend  = 0.05). Moreover, in macrosomia study, women with irregular menstruation and pre-pregnancy BMI ≥ 24 kg/m 2 had higher risk than those with one factor (13.31 vs 2.09, P trend  = 0.001). Our study showed that either pre-pregnancy hair dye use or irregular menstruation was associated with abnormal birth weight, especially, their joint effects could furthermore increase the risk of low birth weight infants when these two factors existed simultaneously.

Improvement of individual camouflage through background choice in ground-nesting birds.

PubMed

Stevens, Martin; Troscianko, Jolyon; Wilson-Aggarwal, Jared K; Spottiswoode, Claire N

2017-09-01

Animal camouflage is a longstanding example of adaptation. Much research has tested how camouflage prevents detection and recognition, largely focusing on changes to an animal's own appearance over evolution. However, animals could also substantially alter their camouflage by behaviourally choosing appropriate substrates. Recent studies suggest that individuals from several animal taxa could select backgrounds or positions to improve concealment. Here, we test whether individual wild animals choose backgrounds in complex environments, and whether this improves camouflage against predator vision. We studied nest site selection by nine species of ground-nesting birds (nightjars, plovers and coursers) in Zambia, and used image analysis and vision modeling to quantify egg and plumage camouflage to predator vision. Individual birds chose backgrounds that enhanced their camouflage, being better matched to their chosen backgrounds than to other potential backgrounds with respect to multiple aspects of camouflage. This occurred at all three spatial scales tested (a few cm and five meters from the nest, and compared to other sites chosen by conspecifics), and was the case for the eggs of all bird groups studied, and for adult nightjar plumage. Thus, individual wild animals improve their camouflage through active background choice, with choices highly refined across multiple spatial scales.

Improvement of individual camouflage through background choice in ground-nesting birds

PubMed Central

Stevens, Martin; Troscianko, Jolyon; Wilson-Aggarwal, Jared K.; Spottiswoode, Claire N.

2017-01-01

Animal camouflage is a longstanding example of adaptation. Much research has tested how camouflage prevents detection and recognition, largely focusing on changes to an animal's own appearance over evolution. However, animals could also substantially alter their camouflage by behaviourally choosing appropriate substrates. Recent studies suggest that individuals from several animal taxa could select backgrounds or positions to improve concealment. Here, we test whether individual wild animals choose backgrounds in complex environments, and whether this improves camouflage against predator vision. We studied nest site selection by nine species of ground-nesting birds (nightjars, plovers and coursers) in Zambia, and used image analysis and vision modeling to quantify egg and plumage camouflage to predator vision. Individual birds chose backgrounds that enhanced their camouflage, being better matched to their chosen backgrounds than to other potential backgrounds with respect to multiple aspects of camouflage. This occurred at all three spatial scales tested (a few cm and five meters from the nest, and compared to other sites chosen by conspecifics), and was the case for the eggs of all bird groups studied, and for adult nightjar plumage. Thus, individual wild animals improve their camouflage through active background choice, with choices highly refined across multiple spatial scales. PMID:28890937

A Flexible Nested Sodium and Proton Coil Array with Wideband Matching for Knee Cartilage MRI at 3 Tesla

PubMed Central

Brown, Ryan; Lakshmanan, Karthik; Madelin, Guillaume; Alon, Leeor; Chang, Gregory; Sodickson, Daniel K.; Regatte, Ravinder R.; Wiggins, Graham C.

2015-01-01

Purpose We describe a 6×2 channel sodium/proton array for knee MRI at 3 Tesla. Multi-element coil arrays are desirable because of well-known signal-to-noise ratio advantages over volume and single-element coils. However, low coil-tissue coupling that is characteristic of coils operating at low frequency can make the potential gains from a phased array difficult to realize. Methods The issue of low coil-tissue coupling in the developed six channel sodium receive array was addressed by implementing 1) a mechanically flexible former to minimize coil-to-tissue distance and reduce the overall diameter of the array and 2) a wideband matching scheme that counteracts preamplifier noise degradation caused by coil coupling and a high quality factor. The sodium array was complemented with a nested proton array to enable standard MRI. Results The wideband matching scheme and tight-fitting mechanical design contributed to greater than 30% central SNR gain on the sodium module over a mono-nuclear sodium birdcage coil, while the performance of the proton module was sufficient for clinical imaging. Conclusion We expect the strategies presented in this work to be generally relevant in high density receive arrays, particularly in x-nuclei or small animal applications, or in those where the array is distant from the targeted tissue. PMID:26502310

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.

Nesting songbirds assess spatial heterogeneity of predatory chipmunks by eavesdropping on their vocalizations.

PubMed

Emmering, Quinn C; Schmidt, Kenneth A

2011-11-01

1. Information benefits organisms living in a heterogeneous world by reducing uncertainty associated with decision making. For breeding passerines, information reliably associated with nest failure, such as predator activity, can be used to adjust breeding decisions leading to higher reproductive success. 2. Predator vocalizations may provide a source of current information for songbirds to assess spatial heterogeneity in risk that enables them to make appropriate nest-site and territory placement decisions. 3. To determine whether ground-nesting passerines eavesdrop on a common nest predator, the eastern chipmunk (Tamias striatus), we conducted a playback experiment to create spatial heterogeneity in perceived predation risk. We established three types of playback plots broadcasting: (i) chipmunk vocalizations (increased risk), (ii) frog calls (procedural control) and (iii) no playback (silent control). We conducted point counts from plot centres to compare bird activity among treatments and measured the distance of two ground-nesting species' nests, ovenbird (Seiurus aurocapilla) and veery (Catharus fuscescens), from playback stations. 4. Ground-nesting birds significantly reduced their activities up to 30 m from plot centres in response to playbacks of chipmunk calls suggesting an adjustment of territory placement or a reduction of overt behaviours (e.g. singing frequency). In contrast, less vulnerable canopy-nesting species showed no effect across experimental plots. Correspondingly, veeries and ovenbirds nested significantly further from chipmunk playback stations relative to control stations. Interestingly, the magnitude of this response was more than twice as high in ovenbirds than in veeries. 5. Our findings indicate that some breeding passerines may eavesdrop on predator communication, providing an explanation for how some birds assess spatial heterogeneity in predation risk to make breeding site decisions. Thus, heterospecific eavesdropping may be a common feature of predator-prey interactions that allows birds to avoid nest predators in space and provide greater stability to predator-prey dynamics. © 2011 The Authors. Journal of Animal Ecology © 2011 British Ecological Society.

Comparative study of Gram stain, potassium hydroxide smear, culture and nested PCR in the diagnosis of fungal keratitis.

PubMed

Badiee, Parisa; Nejabat, Mahmood; Alborzi, Abdolvahab; Keshavarz, Fatemeh; Shakiba, Elaheh

2010-01-01

This study seeks to evaluate the efficacy and practicality of the molecular method, compared to the standard microbiological techniques for diagnosing fungal keratitis (FK). Patients with eye findings suspected of FK were enrolled for cornea sampling. Scrapings from the affected areas of the infected corneas were obtained and were divided into two parts: one for smears and cultures, and the other for nested PCR analysis. Of the 38 eyes, 28 were judged to have fungal infections based on clinical and positive findings in the culture, smear and responses to antifungal treatment. Potassium hydroxide, Gram staining, culture and nested PCR results (either positive or negative) matched in 76.3, 42.1, 68.4 and 81.6%, respectively. PCR is a sensitive method but due to the lack of sophisticated facilities in routine laboratory procedures, it can serve only complementarily and cannot replace conventional methods. Copyright © 2010 S. Karger AG, Basel.

Demonstration of EnergyNest thermal energy storage (TES) technology

NASA Astrophysics Data System (ADS)

Hoivik, Nils; Greiner, Christopher; Tirado, Eva Bellido; Barragan, Juan; Bergan, Pâl; Skeie, Geir; Blanco, Pablo; Calvet, Nicolas

2017-06-01

This paper presents the experimental results from the EnergyNest 2 × 500 kWhth thermal energy storage (TES) pilot system installed at Masdar Institute of Science & Technology Solar Platform. Measured data are shown and compared to simulations using a specially developed computer program to verify the stability and performance of the TES. The TES is based on a solid-state concrete storage medium (HEATCRETE®) with integrated steel tube heat exchangers cast into the concrete. The unique concrete recipe used in the TES has been developed in collaboration with Heidelberg Cement; this material has significantly higher thermal conductivity compared to regular concrete implying very effective heat transfer, at the same time being chemically stable up to 450 °C. The demonstrated and measured performance of the TES matches the predictions based on simulations, and proves the operational feasibility of the EnergyNest concrete-based TES. A further case study is analyzed where a large-scale TES system presented in this article is compared to two-tank indirect molten salt technology.

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

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

Industrious leaf cutter ants and their carbon footprints

NASA Astrophysics Data System (ADS)

Swanson, A. C.; Dierick, D.; Trahan, N. A.; Allen, M. F.; Schwendenmann, L.; Harmon, T. C.; Oberbauer, S. F.; Fernandez Bou, A. S.; Zelikova, T. J.

2017-12-01

Leaf cutter ants (LCA) are considered ecosystem engineers in Neotropical forest ecosystems because they alter physical and environmental conditions for other organisms. LCA excavate large underground nests, maintaining intricate tunnels and fungal and waste chambers, and they continuously bring in vast amounts of fresh leaf material. In order to understand their ecosystem-wide impacts, we set out to determine whether their engineering activities fundamentally alter soil structure, soil nutrient pools, and gas fluxes in a wet tropical rainforest in Costa Rica. To directly compare LCA nest to non-nest sites, we utilized embedded sensor arrays with series of soil moisture, CO2, O2, and temperature sensors placed at four soil depths and automated minirhizotrons (AMR) to measure root and hyphal production and turnover. We also collected soils for biogeochemical analyses and measured soil CO2 fluxes and carbon isotope ratios of below-ground CO2 for two years. Our measurements confirmed that LCA alter their soil environment to regulate internal soil CO2 concentrations, moisture, and temperature, increasing O2 concentrations in the process. There were marked differences in soil structure inside nests relative to non-nests and these were associated with increased root and hyphal production and turnover in nests. Soil C, N, P, and their respective degrading enzymes were highly variable among sites and between nests and controls but N and P increased with soil depth and were generally higher in nests than controls. Contrary to our expectations, C mineralization rates were lower in nests but CO2 fluxes were high from nest vents and similar to non-nests elsewhere. At the system scale, LCA appear to fundamentally change the soil environment inside their nests and create spatial heterogeneity in biogeochemical processes and root and hyphal growth, influencing the overall C balance of Neotropical forests.

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.

Effect of Tithonia diversifolia Mulch on Atta cephalotes (Hymenoptera: Formicidae) Nests

PubMed Central

Rodríguez, Jonathan; Montoya-Lerma, James; Calle, Zoraida

2015-01-01

Recent studies have shown an insecticidal effect of Tithonia diversifolia (Hemsl.) Gray (Asterales: Asteraceae) foliage on workers of Atta cephalotes L. and inhibitory effects of this plant on the growth of the symbiotic fungus Leucoagaricus gongylophorus (A. Müler) Singer. To evaluate the potential of T. diversifolia as a biological control treatment of this important pest, we assessed the effect of green manure (mulch) of this plant on natural nests of A. cephalotes, in Cali, Colombia. Three treatments were randomly assigned to 30 nests: 1) green mulch of T. diversifolia, 2) green mulch of Miconia sp., Ruiz & Pav. and 3) unmulched control. Every 2 wk for 6 mo, the surface of the nests was completely covered with leaves. Physical and chemical parameters of nest soil were assessed before the first and after the last application of the mulch. Ant foraging in T. diversifolia-treated nests decreased by 60% after the initial applications of the mulch, while nest surface area decreased by 40%. When the nests covered with T. diversifolia were opened, it was observed that the superficial fungus chambers had been relocated at a greater depth. In addition, microbial activity and soil pH increased by 84% and 12%, respectively, in nests covered with plant residues. In conclusion, the continued use of T. diversifolia mulch reduces foraging activity and negatively affects the internal conditions of the colonies, thereby inducing the ants to relocate the fungus chambers within the nests. PMID:25843585

Association between Helicobacter pylori infection and increased risk of typhoid fever.

PubMed

Bhan, Maharaj K; Bahl, Rajiv; Sazawal, Sunil; Sinha, Anju; Kumar, Ramesh; Mahalanabis, Dilip; Clemens, John D

2002-12-15

Helicobacter pylori infection has been reported to increase the risk of cholera. This nested case-control study was conducted to determine whether H. pylori infection is associated with occurrence of typhoid fever. Eighty-three case subjects of culture-proven typhoid fever were identified through a 1-year surveillance of subjects aged 0-40 years in an urban slum. Two age- and sex-matched neighborhood control subjects were concurrently selected for each case subject. Serum anti-H. pylori immunoglobulin G antibodies were measured in case and neighborhood control subjects. For determining other risk factors, 2 additional community control subjects per case were selected. There was a significant association between the presence of serum anti-H. pylori immunoglobulin G antibodies and typhoid fever (adjusted odds ratio, 2.03; 95% confidence interval, 1.02-4.01). Illiteracy, being part of a nuclear family, nonuse of soap, and consumption of ice cream were also associated with a significantly greater risk of typhoid fever. This study provides the first empiric evidence that H. pylori infection is associated with an increased risk of typhoid fever.

Avian Conservation Practices Strengthen Ecosystem Services in California Vineyards

PubMed Central

Jedlicka, Julie A.; Greenberg, Russell; Letourneau, Deborah K.

2011-01-01

Insectivorous Western Bluebirds (Sialia mexicana) occupy vineyard nest boxes established by California winegrape growers who want to encourage avian conservation. Experimentally, the provision of available nest sites serves as an alternative to exclosure methods for isolating the potential ecosystem services provided by foraging birds. We compared the abundance and species richness of avian foragers and removal rates of sentinel prey in treatments with songbird nest boxes and controls without nest boxes. The average species richness of avian insectivores increased by over 50 percent compared to controls. Insectivorous bird density nearly quadrupled, primarily due to a tenfold increase in Western Bluebird abundance. In contrast, there was no significant difference in the abundance of omnivorous or granivorous bird species some of which opportunistically forage on grapes. In a sentinel prey experiment, 2.4 times more live beet armyworms (Spodoptera exigua) were removed in the nest box treatment than in the control. As an estimate of the maximum foraging services provided by insectivorous birds, we found that larval removal rates measured immediately below occupied boxes averaged 3.5 times greater than in the control. Consequently the presence of Western Bluebirds in vineyard nest boxes strengthened ecosystem services to winegrape growers, illustrating a benefit of agroecological conservation practices. Predator addition and sentinel prey experiments lack some disadvantages of predator exclusion experiments and were robust methodologies for detecting ecosystem services. PMID:22096555

Avian conservation practices strengthen ecosystem services in California vineyards.

PubMed

Jedlicka, Julie A; Greenberg, Russell; Letourneau, Deborah K

2011-01-01

Insectivorous Western Bluebirds (Sialia mexicana) occupy vineyard nest boxes established by California winegrape growers who want to encourage avian conservation. Experimentally, the provision of available nest sites serves as an alternative to exclosure methods for isolating the potential ecosystem services provided by foraging birds. We compared the abundance and species richness of avian foragers and removal rates of sentinel prey in treatments with songbird nest boxes and controls without nest boxes. The average species richness of avian insectivores increased by over 50 percent compared to controls. Insectivorous bird density nearly quadrupled, primarily due to a tenfold increase in Western Bluebird abundance. In contrast, there was no significant difference in the abundance of omnivorous or granivorous bird species some of which opportunistically forage on grapes. In a sentinel prey experiment, 2.4 times more live beet armyworms (Spodoptera exigua) were removed in the nest box treatment than in the control. As an estimate of the maximum foraging services provided by insectivorous birds, we found that larval removal rates measured immediately below occupied boxes averaged 3.5 times greater than in the control. Consequently the presence of Western Bluebirds in vineyard nest boxes strengthened ecosystem services to winegrape growers, illustrating a benefit of agroecological conservation practices. Predator addition and sentinel prey experiments lack some disadvantages of predator exclusion experiments and were robust methodologies for detecting ecosystem services.

Optical systolic solutions of linear algebraic equations

NASA Technical Reports Server (NTRS)

Neuman, C. P.; Casasent, D.

1984-01-01

The philosophy and data encoding possible in systolic array optical processor (SAOP) were reviewed. The multitude of linear algebraic operations achievable on this architecture is examined. These operations include such linear algebraic algorithms as: matrix-decomposition, direct and indirect solutions, implicit and explicit methods for partial differential equations, eigenvalue and eigenvector calculations, and singular value decomposition. This architecture can be utilized to realize general techniques for solving matrix linear and nonlinear algebraic equations, least mean square error solutions, FIR filters, and nested-loop algorithms for control engineering applications. The data flow and pipelining of operations, design of parallel algorithms and flexible architectures, application of these architectures to computationally intensive physical problems, error source modeling of optical processors, and matching of the computational needs of practical engineering problems to the capabilities of optical processors are emphasized.

Nest predation risk influences a cavity-nesting passerine during the post-hatching care period

PubMed Central

Yoon, Jongmin; Kim, Byung-Su; Joo, Eun-Jin; Park, Shi-Ryong

2016-01-01

Some nest predators visually assess parental activities to locate a prey nest, whereas parents modify fitness-related traits to reduce the probability of nest predation, and/or nestlings fledge early to escape the risky nest environment. Here, we experimentally tested if the parental and fledging behaviours of oriental tits (Parus minor) that bred in the nest-box varied with cavity conditions associated with nest predation risk during the nestling period. The entrance of experimental nest-boxes was enlarged to create a long-term risk soon after clutch competition. A short-term risk, using simulated playbacks with a coexisting control bird and avian nest predator sound, was simultaneously applied to the nest-boxes whether or not the long-term risk existed. We found that the parents reduced their hourly feeding trips, and the nestlings fledged early with the long-term risk, although the nest mortality of the two nest-box types was low and did not differ. While this study presents a portion of prey–predator interactions with the associated uncertainties, our results highlight that the entrance size of cavities for small hole-nesting birds may play an important role in determining their fitness-related traits depending upon the degree of perceived risk of nest predation. PMID:27553176

Nest predation risk influences a cavity-nesting passerine during the post-hatching care period.

PubMed

Yoon, Jongmin; Kim, Byung-Su; Joo, Eun-Jin; Park, Shi-Ryong

2016-08-24

Some nest predators visually assess parental activities to locate a prey nest, whereas parents modify fitness-related traits to reduce the probability of nest predation, and/or nestlings fledge early to escape the risky nest environment. Here, we experimentally tested if the parental and fledging behaviours of oriental tits (Parus minor) that bred in the nest-box varied with cavity conditions associated with nest predation risk during the nestling period. The entrance of experimental nest-boxes was enlarged to create a long-term risk soon after clutch competition. A short-term risk, using simulated playbacks with a coexisting control bird and avian nest predator sound, was simultaneously applied to the nest-boxes whether or not the long-term risk existed. We found that the parents reduced their hourly feeding trips, and the nestlings fledged early with the long-term risk, although the nest mortality of the two nest-box types was low and did not differ. While this study presents a portion of prey-predator interactions with the associated uncertainties, our results highlight that the entrance size of cavities for small hole-nesting birds may play an important role in determining their fitness-related traits depending upon the degree of perceived risk of nest predation.

ELF communications system ecological monitoring program: Pollinating insect studies

NASA Astrophysics Data System (ADS)

Strickler, Karen; Schriber, J. Mark

1994-11-01

High voltage transmission lines and the earth's and other magnetic fields have been shown to affect honeybee reproduction, survival, orientation, and nest structure. ELY EM fields could have similar effects on native megachilid bees. Two species in the genus Megachile were abundant in artificial nests at experimental and control areas in Dickinson and Iron Counties in Michigan. Data on their nest architecture, nest activity, and emergence/mortality were collected between 1983 and 1993. Eight hypotheses concerning the possible effects of ELY EM fields were considered using these data. The ELY antenna has been fully operational since the summer of 1989. Tests of the hypotheses compare control vs. experimental areas before and after the ELY antenna became fully operational.

Lufenuron impact upon Anthonomus grandis Boheman (Coleoptera: Curculionidae) midgut and its reflection in gametogenesis.

PubMed

Costa, Hilton Nobre; da Cunha, Franklin Magliano; Cruz, Glaucilane Santos; D'assunção, Carolline Guimarães; Rolim, Guilherme Gomes; Barros, Maria Edna Gomes; Breda, Mariana Oliveira; Teixeira, Alvaro Aguiar Coelho; Teixeira, Valéria Wanderley

2017-04-01

The insecticide Match® (lufenuron), one of the main insect growth regulators used in pest control, has been presented as a viable alternative against the boll weevil, Anthonomus grandis (Coleoptera: Curculionidae), by inhibiting chitin synthesis. Thus, this study aimed to examine whether Match® interferes in the synthesis of the peritrophic matrix, leading to changes in the midgut epithelium, resulting in nutritional deficiency and reflecting, thereby, in the gametogenesis process of A. grandis. Floral cotton buds were immersed in the insecticide solution (800μL of Match®+200mL of distilled water) and offered to the adult insects. The midguts of the insects were evaluated after 24 and 120h after feeding. The gonads were evaluated after 120h. The results showed that Match®, in both evaluation periods, induced histopathological alterations such as disorganization, vacuolization and desquamation of the midgut epithelium; histochemical modifications in the distribution patterns of carbohydrates, although without quantitative changes; and a strong decrease in protein levels. No apoptosis were observed, however, there was an increase in the number of regenerative cell nests. In the testicles, a reduction in the amount of spermatozoids and reduced carbohydrate levels were observed, but no difference in protein levels. The ovarioles presented structural disorganization of follicular cells, yolk reduction and decrease in protein levels, however, no change in carbohydrates levels was noted. Therefore, it is concluded that Match® performs histopathologic and histochemical alterations in the midgut epithelium and the gonads of A. grandis adults, reflecting in the gametogenesis process, presenting itself as a promising tool in the management of this pest on cotton crops. Copyright © 2016 Elsevier Inc. All rights reserved.

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.

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.

Association between medication prescription for atopic diseases and attention-deficit/hyperactivity disorder.

PubMed

van der Schans, Jurjen; Pleiter, Janine C; de Vries, Tjalling W; Schuiling-Veninga, Catharina C M; Bos, Jens H J; Hoekstra, Pieter J; Hak, Eelko

2016-08-01

Data on the association between atopic diseases and attention-deficit/hyperactivity disorder (ADHD) have been inconclusive. To assess whether children with drug-treated ADHD are more likely to receive treatment for asthma, allergic rhinitis, or eczema before the start of ADHD medication use compared with controls and to examine the effect of parents receiving medication for ADHD and atopic diseases on ADHD medication use in their offspring. We conducted a retrospective nested case-control study among children (6-12 years of age) using the Groningen University prescription database. Cases were defined as children with at least 2 prescriptions of methylphenidate within 12 months. For each case, 4 controls were matched on age, sex, and regional area code. Parental prescription data were linked to cases and controls to assess the influence of parents receiving medication for ADHD and atopic diseases on ADHD medication use in their offspring. We identified 4257 cases and 17,028 matched controls. Drug treatment for asthma, allergic rhinitis, and eczema was more common in cases than controls (adjusted odds ratios [aORs], 1.4 [95% confidence interval (CI), 1.3-1.6], 1.4 [95% CI, 1.1-1.8], and 1.3 [95% CI, 1.1-1.5], respectively). Medication for allergic rhinitis and asthma among parents was associated with ADHD treatment in their children (aORs, 1.3 [95% CI, 1.1-1.5] and 1.2 [95% CI, 1.1-1.3], respectively). This study provides further evidence to support the hypothesis that atopic diseases are associated with ADHD. The parental-offspring association suggests a possible genetic and/or environmental component. Copyright © 2016 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

CyNEST: a maintainable Cython-based interface for the NEST simulator

PubMed Central

Zaytsev, Yury V.; Morrison, Abigail

2014-01-01

NEST is a simulator for large-scale networks of spiking point neuron models (Gewaltig and Diesmann, 2007). Originally, simulations were controlled via the Simulation Language Interpreter (SLI), a built-in scripting facility implementing a language derived from PostScript (Adobe Systems, Inc., 1999). The introduction of PyNEST (Eppler et al., 2008), the Python interface for NEST, enabled users to control simulations using Python. As the majority of NEST users found PyNEST easier to use and to combine with other applications, it immediately displaced SLI as the default NEST interface. However, developing and maintaining PyNEST has become increasingly difficult over time. This is partly because adding new features requires writing low-level C++ code intermixed with calls to the Python/C API, which is unrewarding. Moreover, the Python/C API evolves with each new version of Python, which results in a proliferation of version-dependent code branches. In this contribution we present the re-implementation of PyNEST in the Cython language, a superset of Python that additionally supports the declaration of C/C++ types for variables and class attributes, and provides a convenient foreign function interface (FFI) for invoking C/C++ routines (Behnel et al., 2011). Code generation via Cython allows the production of smaller and more maintainable bindings, including increased compatibility with all supported Python releases without additional burden for NEST developers. Furthermore, this novel approach opens up the possibility to support alternative implementations of the Python language at no cost given a functional Cython back-end for the corresponding implementation, and also enables cross-compilation of Python bindings for embedded systems and supercomputers alike. PMID:24672470

Risk of hematological malignancies among Chernobyl liquidators

PubMed Central

Kesminiene, Ausrele; Evrard, Anne-Sophie; Ivanov, Viktor K.; Malakhova, Irina V.; Kurtinaitis, Juozas; Stengrevics, Aivars; Tekkel, Mare; Anspaugh, Lynn R.; Bouville, André; Chekin, Sergei; Chumak, Vadim V.; Drozdovitch, Vladimir; Gapanovich, Vladimir; Golovanov, Ivan; Hubert, Phillip; Illichev, Sergei V.; Khait, Svetlana E.; Krjuchkov, Viktor P.; Maceika, Evaldas; Maksyoutov, Marat; Mirkhaidarov, Anatoly K.; Polyakov, Semion; Shchukina, Natalia; Tenet, Vanessa; Tserakhovich, Tatyana I.; Tsykalo, Aleksandr; Tukov, Aleksandr R.; Cardis, Elisabeth

2010-01-01

A case-control study of hematological malignancies was conducted among Chernobyl liquidators (accident recovery workers) from Belarus, Russia and Baltic countries in order to assess the effect of low-to-medium dose protracted radiation exposures on the relative risk of these diseases. The study was nested within cohorts of liquidators who had worked in 1986–87 around the Chernobyl plant. 117 cases (69 leukemia, 34 non-Hodgkin Lymphoma (NHL) and 14 other malignancies of lymphoid and hematopoietic tissue) and 481 matched controls were included in the study. Individual dose to the bone marrow and uncertainties were estimated for each subject. The main analyses were restricted to 70 cases (40 leukemia, 20 NHL and 10 other) and their 287 matched controls with reliable information on work in the Chernobyl area. Most subjects received very low doses (median 13 mGy). For all diagnoses combined, a significantly elevated OR was seen at doses of 200 mGy and above. The Excess Relative Risk (ERR) per 100 mGy was 0.60 (90% confidence interval (CI): −0.02, 2.35). The corresponding estimate for leukemia excluding chronic lymphoid leukemia (CLL) was 0.50 (90%CI −0.38, 5.7). It is slightly higher than, but statistically compatible with, those estimated from a-bomb survivors and recent low dose-rate studies. Although sensitivity analyses showed generally similar results, we cannot rule out the possibility that biases and uncertainties could have led to over or underestimation of the risk in this study. PMID:19138033

Risk factors for psychosis: impaired social and role functioning.

PubMed

Cornblatt, Barbara A; Carrión, Ricardo E; Addington, Jean; Seidman, Larry; Walker, Elaine F; Cannon, Tyronne D; Cadenhead, Kristin S; McGlashan, Thomas H; Perkins, Diana O; Tsuang, Ming T; Woods, Scott W; Heinssen, Robert; Lencz, Todd

2012-11-01

Risk for psychosis is currently defined primarily on the basis of attenuated positive symptoms (APS), with no inclusion of the functional deficits characteristic of schizophrenia. Impaired social and role functioning have been of interest for reflecting poor outcome but far less is known about the developmental impact of these deficits as vulnerability or risk factors. Age-appropriate social and role functioning were prospectively assessed in 100 individuals at clinical high risk (CHR) for psychosis included in the 8-site North American Prodromal Longitudinal Study database. A nested case-control design was used to compare changes in social and role functioning in 26 individuals converting to psychosis shortly after baseline assessment and 24 converting over a year later. Individuals in each converter subgroup were directly matched to a non-converter at the same site, controlling for time to conversion, age, gender, and severity of baseline symptoms. At baseline, CHR subjects who later became psychotic were significantly more likely to be impaired socially than matched non-converters. Onset of psychosis did not further disrupt social difficulties. Role functioning showed some of the same trends, but the overall pattern was not as consistent as for the social domain. Controlling for neurocognition did not change the pattern of group differences. Early impaired social functioning appears to be a risk factor for psychosis and, added to APS, could potentially contribute to accurate identification of CHR individuals and provide a new direction for early intervention to reduce long-term disability.

The value of reasons for encounter in early detection of colorectal cancer.

PubMed

van Boxtel-Wilms, Susan J M; van Boven, Kees; Bor, J H Hans; Bakx, J Carel; Lucassen, Peter; Oskam, Sibo; van Weel, Chris

2016-06-01

Symptoms with a high predictive power for colorectal cancer (CRC) do not exist. To explore the predictive value of patients' reason for encounter (RFE) in the two years prior to the diagnosis of CRC. A retrospective nested case-control study using prospectively collected data from electronic records in general practice over 20 years. Matching was done based on age (within two years), gender and practice. The positive likelihood ratios (LR+) and odds ratios (OR) were calculated for RFE between cases and controls in the two years before the index date. We identified 184 CRC cases and matched 366 controls. Six RFEs had significant LR + and ORs for CRC, which may have high predictive power. These RFEs are part of four chapters in the International Classification of Primary Care (ICPC) that include tiredness (significant at 3-6 months prior to the diagnosis; LR+ 2.6 and OR 3.07; and from 0 to 3 months prior to the diagnosis; LR+ 2.0 and OR 2.36), anaemia (significant at three months before diagnosis; LR+ 9.8 and OR 16.54), abdominal pain, rectal bleeding and constipation (significant at 3-6 months before diagnosis; LR+ 3.0 and OR 3.33; 3 months prior to the diagnosis LR+ 8.0 and OR 18.10) and weight loss (significant at three months before diagnosis; LR+ 14.9 and OR 14.53). Data capture and organization in ICPC permits study of the predictive value of RFE for CRC in primary care.

Occupational kidney disease among Chinese herbalists exposed to herbs containing aristolochic acids.

PubMed

Yang, Hsiao-Yu; Wang, Jung-Der; Lo, Tsai-Chang; Chen, Pau-Chung

2011-04-01

Many Chinese herbs contain aristolochic acids (ALAs) which are nephrotoxic and carcinogenic. The objective of this study was to identify whether exposure to herbs containing ALAs increased the risk of kidney disease among Chinese herbalists. A nested case-control study was carried out on 6538 Chinese herbalists registered between 1985 and 1998. All incident cases of chronic renal failure reported to the Database of Catastrophic Illness of the National Health Insurance Bureau between 1995 and 2000 were defined as the case group. Up to four controls without renal failure were randomly matched to each case by sex and year of birth. A structured questionnaire survey was administered between November and December 2002. The Mantel-Haenszel method and conditional logistic regression were used to estimate the risks. 40 cases and 98 matched controls were included in the final analysis. After adjusting for age, frequent analgesic use, and habitual consumption of alcohol, fermented or smoked food, we found manufacturing and selling Chinese herbal medicine (OR 3.43, 95% CI 1.16 to 10.19), processing, selling or dispensing herbal medicines containing Fangji (OR 4.17, 95% CI 1.36 to 12.81), living in the workplace (OR 3.14, 95% CI 1.11 to 8.84) and a history of taking of herbal medicines containing Fangji (frequently or occasionally) (OR 5.42, 95% CI 1.18 to 24.96) were significantly associated with renal failure. Occupational exposure to and consumption of herbs containing ALAs increases the risk of renal failure in Chinese herbalists.

A Prospective Study Investigating Pre-diagnostic Leukocyte Telomere Length and Risk of Developing Rheumatoid Arthritis in Women

PubMed Central

Prescott, Jennifer; Karlson, Elizabeth W.; Orr, Esther H.; Zee, Robert Y.L.; De Vivo, Immaculata; Costenbader, Karen H.

2015-01-01

Objective To prospectively examine the association between leukocyte telomere length (LTL) and subsequent RA development in women. Methods Using a case-control design nested within the prospective Nurses’ Health Study (NHS), Nurses’ Health Study II (NHSII), and Women’s Health Study (WHS), each validated case of RA with a pre-diagnostic blood sample was matched to three controls by cohort, age, menopausal status, postmenopausal hormone therapy, and blood collection covariates. We measured telomere length in genomic DNA extracted from stored buffy coat samples using quantitative PCR. We used unconditional logistic regression to determine odds ratios (OR) and 95% confidence intervals (CI), and random-effects meta-analysis to combine study results. Results In total, we analyzed 296 incident RA cases and 827 matched controls. Mean age of diagnosis among women who developed RA was 60.5 in NHS/NHSII and 61.3 in WHS. Meta-analysis demonstrated that longer pre-diagnostic LTL was associated with increased RA risk when women in the longest vs. shortest LTL tertile were compared (OR=1.51, 95% CI=1.03–2.23; pheterogeneity=0.27). However, statistically significant between study heterogeneity was observed for the intermediate tertile category (pheterogeneity=0.008). We did not observe heterogeneity by menopausal status, inflammatory cytokine levels, age at diagnosis, age at blood collection, body mass index, seropositivity, or HLA-DRB1 shared epitope status. Conclusion Our results do not support a role for short LTL preceding RA development. PMID:26773113

Effect of Tithonia diversifolia mulch on Atta cephalotes (Hymenoptera: Formicidae) nests.

PubMed

Rodríguez, Jonathan; Montoya-Lerma, James; Calle, Zoraida

2015-01-01

Recent studies have shown an insecticidal effect of Tithonia diversifolia (Hemsl.) Gray (Asterales: Asteraceae) foliage on workers of Atta cephalotes L. and inhibitory effects of this plant on the growth of the symbiotic fungus Leucoagaricus gongylophorus (A. Müler) Singer. To evaluate the potential of T. diversifolia as a biological control treatment of this important pest, we assessed the effect of green manure (mulch) of this plant on natural nests of A. cephalotes, in Cali, Colombia. Three treatments were randomly assigned to 30 nests: 1) green mulch of T. diversifolia, 2) green mulch of Miconia sp., Ruiz & Pav. and 3) unmulched control. Every 2 wk for 6 mo, the surface of the nests was completely covered with leaves. Physical and chemical parameters of nest soil were assessed before the first and after the last application of the mulch. Ant foraging in T. diversifolia-treated nests decreased by 60% after the initial applications of the mulch, while nest surface area decreased by 40%. When the nests covered with T. diversifolia were opened, it was observed that the superficial fungus chambers had been relocated at a greater depth. In addition, microbial activity and soil pH increased by 84% and 12%, respectively, in nests covered with plant residues. In conclusion, the continued use of T. diversifolia mulch reduces foraging activity and negatively affects the internal conditions of the colonies, thereby inducing the ants to relocate the fungus chambers within the nests. © The Author 2015. Published by Oxford University Press on behalf of the Entomological Society of America.

Using the network to achieve energy efficiency

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

Giglio, M.

1995-12-01

Novell, the third largest software company in the world, has developed Netware Embedded Systems Technology (NEST). NEST will take the network deeper into non-traditional computing environments and will imbed networking into more intelligent devices. Ultimately, this will lead to energy efficiencies in the office. NEST can make point-of-sale terminals, alarm systems, televisions, traffic controls, printers, lights, fax machines, copiers, HVAC controls, PBX machines, etc., either intelligent or more intelligent than they are currently. The mission statement for this particular group is to integrate over 30 million new intelligent devices into the workplace and the home with Novell networks by 1997.more » Computing trends have progressed from mainframes in the 1960s to keys, security systems, and airplanes in the year 2000. In fact, the new Boeing 777 has NEST in it, and it also has network servers on board. NEST enables the embedded network with the ability to put intelligence into devices. This gives one more control of the devices from wherever one is. For example, the pharmaceutical industry could use NEST to coordinate what the consumer is buying, what is in the warehouse, what the manufacturing plant is tooled for, and so on. Through NEST technology, the pharmaceutical industry now uses a camera that takes pictures of the pills. It can see whether an {open_quotes}overdose{close_quotes} or {open_quotes}underdose{close_quotes} of a particular type of pill is being manufactured. The plant can be shut down and corrections made immediately.« less

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.

Leaf Cutter Ant (Atta cephalotes) Soil Modification and In Situ CO2 Gas Dynamics in a Neotropical Wet Forest

NASA Astrophysics Data System (ADS)

Fernandez Bou, A. S.; Carrasquillo Quintana, O.; Dierick, D.; Harmon, T. C.; Johnson, S.; Schwendenmann, L.; Zelikova, T. J.

2016-12-01

The goal of this work is to advance our understanding of soil carbon cycling in highly productive neotropical wet forests. More specifically, we are investigating the influence of leaf cutter ants (LCA) on soil CO2 gas dynamics in primary and secondary forest soils at La Selva Biological Station, Costa Rica. LCA are the dominant herbivore in tropical Americas, responsible for as much as 50% of the total herbivory. Their presence is increasing and their range is expanding because of forest fragmentation and other human impacts. We installed gas sampling wells in LCA (Atta cephalotes) nest and control sites (non-nests in the same soil and forest settings). The experimental design encompassed land cover (primary and secondary forest) and soil type (residual and alluvial). We collected gas samples monthly over an 18-month period. Several of the LCA nests were abandoned during this period. Nevertheless, we continued to sample these sites for LCA legacy effects. In several of the sites, we also installed sensors to continuously monitor soil moisture content, temperature, and CO2 levels. Within the 18-month period we conducted a 2-month field campaign to collect soil and nest vent CO2 efflux data from 3 of the nest-control pairs. Integrating the various data sets, we observed that for most of the sites nest and control soils behaved similarly during the tropical dry season. However, during the wet season gas well CO2 concentrations increased in the control sites while levels in the nests remained at dry season levels. This outcome suggests that ants modify soil gas transport properties (e.g., tortuosity). In situ time series and efflux sampling campaign data corroborated these findings. Abandoned nest CO2 levels were similar to those of the active nests, supporting the notion of a legacy effect from LCA manipulations. For this work, the period of abandonment was relatively short (several months to 1 year maximum), which appears to be insufficient for estimating the duration effect. Overall, these results demonstrate that LCA exert a significant effect on carbon cycling in rain forest soils.

Effects of grazing and burning on densities and habitats of breeding ducks in North Dakota

USGS Publications Warehouse

Kruse, Arnold D.; Bowen, Bonnie S.

1996-01-01

Native grassland communities controlled by public agencies become increasingly important to the maintenance of many wildlife species as privately owned grasslands are destroyed or degraded for farming, mining, and development. In turn, wildlife on publicly owned grasslands are affected by the management techniques practiced by local managers. We studied the effects of grazing and prescribed burning on upland-nesting ducks and the structure and type of vegetation from 1980 to 1988 at the Lostwood National Wildlife Refuge (NWR) in northwestern North Dakota. Mallard (Anas platyrhynchos), the most abundant species at Lostwood NWR, had lower (P < 0.05) annual nest densities on experimental and control fields in the later years than in the early years of the study. Spring burning reduced (P = 0.016) nest densities of gadwall (A. strepera). Spring grazing reduced nest densities of gadwall (P = 0.014), and blue-winged teal (A. discors, P = 0.023). Nest density of gadwall increased (P = 0.018) after spring grazing was terminated. On the summer burn/spring graze fields, blue-winged teal had lower (P = 0.010) nest densities after treatments (1987-88) than before treatments (1980-81). Nest success was high (mallard 34%, gadwall 45%, blue-winged teal 31%) but was not influenced (P 0.16) by the burning and grazing treatments. During the study, the amount of grass/brush increased, whereas the amount of brush and brush/grass decreased on control and treatment fields. During the years with burning and grazing, short vegetation increased and tall vegetation decreased. On the spring graze fields, 1 year after grazing ended the vegetation was similar to that on the control fields. The spring burn and summer burn/spring graze fields recovered more slowly. Brushy species such as western snowberry (Symphoricarpos occidentalis) provided attractive nesting habitat for many upland-nesting waterfowl species, especially mallard, gadwall, American wigeon (A. americana), and northern pintail (A. acuta). Habitat needs of additional species of wildlife that depend on grasslands may need to be considered when deciding how to manage habitat.

Conservation implications when the nest predators are known

USGS Publications Warehouse

Ribic, Christine; Thompson, Frank

2012-01-01

Conservation and management of passerines has largely focused on habitat manipulation or restoration because the natural communities on which these birds depend have been destroyed and fragmented. However, productivity is another important aspect of avian conservation, and nest predation can be a large source of nesting mortality for passerines. Recent studies using video surveillance to identify nest predators allow researchers to start evaluating what methods could be used to mitigate nest predation to help passerines of conservation concern. From recent studies, we identified latitudinal and habitat-related patterns in the importance of predator groups that depredate passerine nests. We then reviewed how knowledge of specific nest predators can benefit conservation of bird species of concern. Mammals were the dominant predator group in northern grasslands. Snakes were the dominant predator group in southern habitats. Fire ants were only a nest predator in southern latitudes. Differences in the importance of predator species or groups were likely the result of both their geographic patterns of distribution and habitat preferences. Some direct and indirect predator control measures developed for waterfowl management potentially could be used to benefit passerine productivity. We reviewed three examples-cowbirds, snakes in shrublands, and ground squirrels in grasslands-to illustrate how different predator control strategies may be needed in different situations. Mitigation of passerine nest predation will need to be based on knowledge of predator communities to be effective. This requires large samples of predation events with identified predators; video technology is essential for this task.

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.

Tachycardia may prognosticate life- or organ-threatening diseases in children with abdominal pain.

PubMed

Hayakawa, Itaru; Sakakibara, Hiroshi; Atsumi, Yukari; Hataya, Hiroshi; Terakawa, Toshiro

2017-06-01

Abdominal pain is common in children, but expeditious diagnosis of life- or organ-threatening diseases can be challenging. An evidence-based definition of tachycardia in children was established recently, but its diagnostic utility has not yet been studied. To test the hypothesis that abdominal pain with tachycardia may pose a higher likelihood of life- or organ-threatening diseases in children. A nested case-control study was conducted in a pediatric emergency department in 2013. Tachycardia was defined as a resting heart rate of more than 3 standard deviations above the average for that age. Life- or organ-threatening diseases were defined as "disorders that might result in permanent morbidity or mortality without appropriate intervention." A triage team recorded vital signs before emergency physicians attended patients. Patients with tachycardia (cases) and without tachycardia (controls) were systematically matched for age, sex, and month of visit. The groups were compared for the presence of life- or organ-threatening diseases. There were 1683 visits for abdominal pain, 1512 of which had vital signs measured at rest. Eighty-three patients experienced tachycardia, while 1429 did not. Fifty-eight cases and 58 controls were matched. Life- or organ-threatening diseases were more common in the case group (19%) than the control group (5%, p=0.043). The relative risk of tachycardia to the presence of the diseases was 3.7 (95% confidence interval 1.2-12.0). Tachycardia significantly increased the likelihood of life- or organ-threatening diseases. Tachycardia in children with abdominal pain should alert emergency physicians to the possibility of serious illness. Copyright © 2017 Elsevier Inc. All rights reserved.

The Influence of Health and Lifestyle Characteristics on the Relation of Serum 25-Hydroxyvitamin D With Risk of Colorectal and Breast Cancer in Postmenopausal Women

PubMed Central

Neuhouser, Marian L.; Manson, JoAnn E.; Millen, Amy; Pettinger, Mary; Margolis, Karen; Jacobs, Elizabeth T.; Shikany, James M.; Vitolins, Mara; Adams-Campbell, Lucile; Liu, Simin; LeBlanc, Erin; Johnson, Karen C.; Wactawski-Wende, Jean

2012-01-01

The authors’ objective was to discern whether lifestyle or health-related factors were confounders, effect modifiers, or irrelevant with regard to understanding observational associations of serum 25-hydroxyvitamin D (25(OH)D) with colorectal and breast cancer. The authors conducted nested case-control studies of colorectal cancer (310 cases, 310 controls) and breast cancer (1,080 cases, 1,080 controls) in the Women’s Health Initiative Calcium and Vitamin D Clinical Trial (1994–2005). Case-control matching factors included age, latitude, race/ethnicity, and blood collection date. Serum 25(OH)D was assayed in baseline fasting blood. Conditional logistic regression was used to estimate odds ratios for each cancer by serum 25(OH)D concentration, comparing the relative effects of successively adding body mass index, physical activity, and other health and lifestyle characteristics particular to each cancer. In models with matching factors only, low (vs. high) serum 25(OH)D was associated with a colorectal cancer odds ratio of 2.72 (95% confidence interval (CI): 1.55, 4.77) and a breast cancer odds ratio of 1.33 (95% CI: 1.02, 1.72). In multivariate-adjusted models for colorectal cancer, the association strengthened (OR = 4.45, 95% CI: 1.96, 10.10). However, in multivariate-adjusted breast cancer models, associations were no longer significant (OR = 1.06, 95% CI: 0.78, 1.43). Adjusting for health and lifestyle characteristics has differential effects depending on the cancer site; when modeling such relations, investigators should take these factors into account. PMID:22362582

Use of antiepileptic drugs and risk of fractures: case-control study among patients with epilepsy.

PubMed

Souverein, P C; Webb, D J; Weil, J G; Van Staa, T P; Egberts, A C G

2006-05-09

To study the association between use of antiepileptic drugs (AEDs) and risk of fractures. The authors obtained data from the General Practice Research Database (GPRD). A case-control study was nested within a cohort of patients with active epilepsy. Cases were patients with a first fracture after cohort entry. Up to four controls were matched to each case by practice, sex, year of birth, timing of first epilepsy diagnosis, index date, and duration of GPRD history. Cumulative exposure to AEDs was assessed by summing the duration of all AED prescriptions. A distinction was made between AEDs that induce the hepatic cytochrome P-450 enzyme system and AEDs that do not. Medical conditions and drugs known to be associated with bone metabolism or falls were evaluated as potential confounders. Conditional logistic regression analysis was used to calculate odds ratios (ORs) and 95% CIs. The study population comprised 1,018 cases and 1,842 matched controls. The risk of fractures increased with cumulative duration of exposure (p for trend < 0.001), with the strongest association for greater than 12 years of use: adjusted OR 4.15 (95% CI 2.71 to 6.34). Risk estimates were higher in women than in men. There was no difference between users of AEDs that induce and AEDs that do not induce the hepatic cytochrome P-450 system. Long-term use of AEDs was associated with an increased risk of fractures, especially in women. More research on mechanisms of AED-induced bone breakdown and female vulnerability to the effects of AEDs on bone health is warranted.

Cancer complicating systemic lupus erythematosus – a dichotomy emerging from a nested case-control study

PubMed Central

Kenu, E; Isenberg, DA

2013-01-01

Objectives We determined whether any individual cancers are increased or decreased in a cohort of 595 patients with systemic lupus erythematosus (SLE) followed for up to 32 years at the University College London Hospitals Lupus Clinic, looking for any associated clinical or serological factors and the prognosis after cancer diagnosis. Methods We undertook a careful retrospective review of the medical records and identified all individuals diagnosed with cancer. For controls, we selected three other patients in the cohort who had not developed cancer, carefully matched for age, sex, ethnicity and disease duration, to determine if any obvious differences emerged in a nested case-control design. Results Thirty-three patients developed cancer after being diagnosed with SLE. There was a statistically insignificant small increase in overall cancer risk, standardized incidence ratios (SIRs) 1.05 (95% CI 0.52–1.58) and increased SIRs for cervical, prostate, anal and pancreatic cancers and reduction in breast cancer SIRs. Haematological and musculoskeletal manifestations, anticardiolipin and antithyroid globulin antibodies were found to be positively associated with cancer risk in multivariate analysis. There was no drug, dose or duration was associated with cancer risk. There was a reduction in survival with a cancer fatality rate of 84.2% (p < 0.0001). Conclusion We found a very small but statistically insignificant increased cancer risk with reduction in survival. Whereas some cancers appear to be more common in SLE, notably prostate and cervical cancer, others, particularly breast cancer, are less frequent. Multiple clinical and serological factors are involved in the increased risk of malignancy in SLE. No drug dose or duration effect was identified. PMID:23857987

Prenatal exposure to glycol ethers and cryptorchidism and hypospadias: a nested case-control study.

PubMed

Warembourg, Charline; Botton, Jérémie; Lelong, Nathalie; Rouget, Florence; Khoshnood, Babak; Le Gléau, Florent; Monfort, Christine; Labat, Laurence; Pierre, Fabrice; Heude, Barbara; Slama, Rémy; Multigner, Luc; Charles, Marie-Aline; Cordier, Sylvaine; Garlantézec, Ronan

2018-01-01

Glycol ethers (GE) are oxygenated solvents frequently found in occupational and consumer products. Some of them are well-known testicular and developmental animal toxicants. This study aims to evaluate the risk of male genital anomalies in association with prenatal exposure to GE using urinary biomarkers of exposure. We conducted a case-control study nested in two joint mother-child cohorts (5303 pregnant women). Cases of cryptorchidism and hypospadias were identified at birth and confirmed during a 2-year follow-up period (n=14 cryptorchidism and n=15 hypospadias). Each case was matched to three randomly selected controls within the cohorts for region of inclusion and gestational age at urine sampling. Concentrations of five GE acidic metabolites were measured in spot maternal urine samples collected during pregnancy. ORs were estimated with multivariate conditional logistic regressions including a Firth's penalisation. Detection rates of urinary GE metabolites ranged from 8% to 93% and only two were sufficiently detected (>33%) in each cohort to be studied: methoxyacetic acid (MAA) and phenoxyacetic acid (PhAA). A significantly higher risk of hypospadias was associated with the highest tertile of exposure to MAA: OR (95% CI) 4.5(1.4 to 23.4). No association were observed with urinary concentration of PhAA, nor with the risk of cryptorchidism. In view of the toxicological plausibility of our results, this study, despite its small sample size, raises concern about the potential developmental toxicity of MAA on the male genital system and calls for thorough identification of current sources of exposure to MAA. © 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.

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.

Lowering prolactin reduces post-hatch parental care in male and female zebra finches (Taeniopygia guttata).

PubMed

Smiley, Kristina O; Adkins-Regan, Elizabeth

2018-02-01

Parental care is a widespread phenomenon observed in many diverse taxa. Neuroendocrine systems have long been thought to play an important role in stimulating the onset of parental behavior. In most birds with altricial young, circulating prolactin (PRL) levels are low during non-breeding times and significantly increase during late incubation and early post-hatch chick care. Because of this pattern, PRL has been suggested to be involved in the initiation of parental care in birds, but rarely has this hypothesis been causally tested. To begin testing the hypothesis, we inhibited the release of endogenous PRL with bromocriptine (BR) on the 3days prior to hatching in incubating parents and the first 2days of post-hatch care, when PRL was found to be highest in zebra finches. Nest temperatures were recorded during all 5days and parental behavior was recorded on days 1-2 post-hatch. In addition to hormonal systems, reproductive experience may also influence parental care; therefore, we tested age-matched inexperienced and experienced pairs in each group. BR either eliminated or drastically reduced chick brooding and feeding behavior, resulting in decreased nest temperatures on days 1 and 2 post-hatch. Experienced control birds fed chicks more than inexperienced birds and control females fed more than males. Chick feeding behavior was positively correlated in control male-female pairs, but not in BR pairs. This is one of the few causal studies to demonstrate that PRL is necessary for post-hatch care in a biparental songbird, and is the first to show this effect in zebra finches. Copyright © 2017 Elsevier Inc. All rights reserved.

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

Immunodeficiency and the risk of cervical intraepithelial neoplasia 2/3 and cervical cancer: A nested case-control study in the Swiss HIV cohort study.

PubMed

Clifford, Gary M; Franceschi, Silvia; Keiser, Olivia; Schöni-Affolter, Franziska; Lise, Mauro; Dehler, Silvia; Levi, Fabio; Mousavi, Mohsen; Bouchardy, Christine; Wolfensberger, Aline; Darling, Katharine E; Staehelin, Cornelia; Bertisch, Barbara; Kuenzli, Esther; Bernasconi, Enos; Pawlita, Michael; Egger, Matthias

2016-04-01

HIV-infected women are at increased risk of cervical intraepithelial neoplasia (CIN) and invasive cervical cancer (ICC), but it has been difficult to disentangle the influences of heavy exposure to HPV infection, inadequate screening and immunodeficiency. A case-control study including 364 CIN2/3 and 20 ICC cases matched to 1,147 controls was nested in the Swiss HIV Cohort Study (1985-2013). CIN2/3 risk was significantly associated with low CD4+ cell counts, whether measured as nadir [odds ratio (OR) per 100-cell/μL decrease = 1.15, 95% CI: 1.08, 1.22], or at CIN2/3 diagnosis (1.10, 95% CI: 1.04, 1.16). An association was evident even for nadir CD4+ 200-349 versus ≥350 cells/μL (OR = 1.57, 95% CI: 1.09, 2.25). After adjustment for nadir CD4+, a protective effect of >2-year cART use was seen against CIN2/3 (OR versus never cART use = 0.64, 95% CI: 0.42, 0.98). Despite low study power, similar associations were seen for ICC, notably with nadir CD4+ (OR for 50 vs. >350 cells/μL= 11.10, 95% CI: 1.24, 100). HPV16-L1 antibodies were significantly associated with CIN2/3, but HPV16-E6 antibodies were nearly exclusively detected in ICC. In conclusion, worsening immunodeficiency, even at only moderately decreased CD4+ cell counts, is a significant risk factor for CIN2/3 and cervical cancer. © 2015 UICC.

Plasma tea polyphenol levels and subsequent risk of breast cancer among Japanese women: a nested case-control study.

PubMed

Iwasaki, Motoki; Inoue, Manami; Sasazuki, Shizuka; Miura, Tsutomu; Sawada, Norie; Yamaji, Taiki; Shimazu, Taichi; Willett, Walter C; Tsugane, Shoichiro

2010-12-01

Although many in vitro and animal studies have suggested a protective effect of green tea against breast cancer, findings from epidemiological studies have been inconsistent. No study has used prediagnostic biomarkers of tea polyphenols, which might play a protective role. A total of 24,226 women aged 40 to 69 years in the Japan Public Health Center-based Prospective Study who responded to the baseline questionnaire and provided blood in 1990-1995 were followed to December 2002. During a mean 10.6 years of follow-up, 144 newly diagnosed breast cancers were identified. Two matched controls for each case were selected from the cohort. Plasma levels of (-)-epigallocatechin (EGC), (-)-epicatechin (EC), (-)-epigallocatechin-3-gallate (EGCG), and (-)-epicatechin-3-gallate (ECG) were measured, and the odds ratio (OR) of breast cancer according to plasma level was estimated using a conditional logistic regression model. We found no statistically significant association between plasma tea polyphenol levels and breast cancer risk. Adjusted ORs for the highest versus lowest group were 0.90 (95% CI 0.42-1.96; P for trend = 0.98) for EGC, 0.95 (95% CI 0.43-2.08; P for trend = 0.86) for EC, 1.21 (95% CI 0.52-2.80; P for trend = 0.53) for EGCG, and 1.75 (95% CI 0.81-3.78; P for trend = 0.15) for ECG. Stratified analyses according to baseline menopausal status showed no remarkable difference between two strata. This nested case-control study found no overall association between plasma tea polyphenols and the risk of breast cancer in Japan.

Anthropometric predictors of gestational hypertensive disorders in a remote aboriginal community: a nested case-control study.

PubMed

Sina, Maryam; Hoy, Wendy; Wang, Zhiqiang

2014-03-05

Australian Aboriginal women tend to have body shape and pregnancy risk profiles different from other Australian women. This study aims to examine the associations of anthropometric indices with gestational hypertensive disorders (GHD), and to determine the index that can best predict the risk of this condition occurring during pregnancy. This is a nested case-control study. Baseline body mass index (BMI), waist circumference (WC), hip circumference (HC), waist-to-hip ratio (WHR) and waist-to-height ratio (WHtR) were measured as part of a broader health screening program between 1992 and 1995 in a remote Aboriginal community. All subsequent pregnancies among the original participants were identified during 20 year follow-up period through hospital records (up to May 2012). Twenty eight women were diagnosed as having GHD, each of whom were individually matched by age at baseline with five women who were hospitalised for other pregnancy-related conditions and were free from GHD (n = 140). The associations of the baseline anthropometric measurements with GHD were assessed using conditional logistic regression. The best predictor of GHD was WC (OR = 1.8; (95% CI, 1.1-2.9) for one standard deviation increase in WC), followed by BMI with the corresponding OR = 1.7 (95% CI, 1.1- 2.6). Other measurements, HC, WHR, and WHtR, were also positively associated with GHD, but those associations were not statistically significant. WC and BMI prior to pregnancy are anthropometric predictors of GHD in Aboriginal women, and WC is the best predictor. These findings imply the importance of early weight control in preventing GHD in Aboriginal women.

Obesity-related hormones and endometrial cancer among postmenopausal women: a nested case–control study within the B~FIT cohort

PubMed Central

Dallal, Cher M; Brinton, Louise A; Bauer, Douglas C; Buist, Diana S M; Cauley, Jane A; Hue, Trisha F; LaCroix, Andrea; Tice, Jeffrey A; Chia, Chia; Falk, Roni; Pfeiffer, Ruth; Pollak, Michael; Veenstra, Timothy D; Xu, Xia; Lacey, James V

2014-01-01

Endometrial cancer risk is strongly influenced by obesity, but the mechanisms of action remain unclear. Leptin and adiponectin, secreted from adipose tissue, reportedly play a role in such carcinogenic processes as cell proliferation, angiogenesis, and insulin regulation. In this case–control study, nested within the Breast and Bone Follow-up of the Fracture Intervention Trial (n = 15 595), we assessed pre-diagnostic serum leptin, total adiponectin, and high-molecular-weight (HMW) adiponectin in relation to endometrial cancer among postmenopausal women. During the 10-year follow-up, 62 incident endometrial cases were identified and matched to 124 controls on age, geographical site, time of fasting blood draw at baseline (1992–1993), and trial participation status. Adipokines and C-peptide were measured by ELISA. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were estimated via conditional logistic regression, with exposures categorized in tertiles (T). Multivariable models considered C-peptide, BMI (kg/m2), and estradiol (E2) as potential confounders. Endometrial cancer risk was significantly associated with higher leptin levels, adjusted for E2 and C-peptide (ORT3 vs T1 = 2.96; 95% CI, 1.21–7.25; P trend <0.01). After further adjustment for BMI, the estimates were attenuated and the positive trend was no longer statistically significant (ORT3 vs T1 = 2.11; 95% CI, 0.69–6.44; P trend = 0.18). No significant associations were observed with adiponectin or HMW adiponectin and endometrial cancer. Our findings with leptin suggest that the leptin–BMI axis might increase endometrial cancer risk through mechanisms other than estrogen-driven proliferation. Continued exploration of these pathways in larger prospective studies may help elucidate mechanisms underlying observed obesity–endometrial cancer associations. PMID:23222000

Obesity-related hormones and endometrial cancer among postmenopausal women: a nested case-control study within the B~FIT cohort.

PubMed

Dallal, Cher M; Brinton, Louise A; Bauer, Douglas C; Buist, Diana S M; Cauley, Jane A; Hue, Trisha F; Lacroix, Andrea; Tice, Jeffrey A; Chia, Victoria M; Falk, Roni; Pfeiffer, Ruth; Pollak, Michael; Veenstra, Timothy D; Xu, Xia; Lacey, James V

2013-02-01

Endometrial cancer risk is strongly influenced by obesity, but the mechanisms of action remain unclear. Leptin and adiponectin, secreted from adipose tissue, reportedly play a role in such carcinogenic processes as cell proliferation, angiogenesis, and insulin regulation. In this case-control study, nested within the Breast and Bone Follow-up of the Fracture Intervention Trial (n=15,595), we assessed pre-diagnostic serum leptin, total adiponectin, and high-molecular-weight (HMW) adiponectin in relation to endometrial cancer among postmenopausal women. During the 10-year follow-up, 62 incident endometrial cases were identified and matched to 124 controls on age, geographical site, time of fasting blood draw at baseline (1992-1993), and trial participation status. Adipokines and C-peptide were measured by ELISA. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were estimated via conditional logistic regression, with exposures categorized in tertiles (T). Multivariable models considered C-peptide, BMI (kg/m(2)), and estradiol (E2) as potential confounders. Endometrial cancer risk was significantly associated with higher leptin levels, adjusted for E2 and C-peptide (OR(T3 vs T1)=2.96; 95% CI, 1.21-7.25; P trend <0.01). After further adjustment for BMI, the estimates were attenuated and the positive trend was no longer statistically significant (OR(T3 vs T1)=2.11; 95% CI, 0.69-6.44; P trend=0.18). No significant associations were observed with adiponectin or HMW adiponectin and endometrial cancer. Our findings with leptin suggest that the leptin-BMI axis might increase endometrial cancer risk through mechanisms other than estrogen-driven proliferation. Continued exploration of these pathways in larger prospective studies may help elucidate mechanisms underlying observed obesity-endometrial cancer associations.

Nested case-control study of night shift work and breast cancer risk among women in the Danish military.

PubMed

Hansen, Johnni; Lassen, Christina F

2012-08-01

Growing but limited evidence suggests that night shift work is associated with breast cancer. The authors conducted a nationwide case-control study nested within a cohort of 18,551 female military employees born in 1929-1968 to investigate the risk for breast cancer after night shift work and to explore the role of leisure time sun exposure and diurnal preference. The authors documented 218 cases of breast cancer (1990-2003) and selected 899 age-matched controls from the cohort by incidence density sampling. Information on shift work, sun exposure habits, diurnal preference and other potential confounders was obtained from a structured questionnaire. ORs were estimated by multivariate conditional logistic regression. Overall, the authors observed an adjusted OR of 1.4 (95% CI 0.9 to 2.1) among women with ever compared with never night shifts. The RR for breast cancer tended to increase with increasing number of years of night shift work (p=0.03) and with cumulative number of shifts (p=0.02),with a neutral risk for fewer than three night shifts per week. The OR for the group with the highest tertile of cumulative exposure was 2.3 (95% CI 1.2 to 4.6). The most pronounced effect of night shift work on breast cancer risk was observed in women with morning chronotype preference and intense night shifts (OR=3.9, 95% CI 1.6 to 9.5). Night shift workers tended to sunbathe more frequently than day workers. The results indicate that frequent night shift work increases the risk for breast cancer and suggest a higher risk with longer duration of intense night shifts. Women with morning preference who worked on night shifts tended to have a higher risk than those with evening preference.

Cardiovascular, Rheumatologic, and Pharmacologic Predictors of Stroke in Patients With Rheumatoid Arthritis: A Nested, Casee–Control Study

PubMed Central

Nadareishvili, Zurab; Michaud, Kaleb; Hallenbeck, John M.; Wolfe, Frederick

2009-01-01

Objective To determine the risk of stroke in patients with rheumatoid arthritis (RA) and risk factors associated with stroke. Methods We performed nested case–control analyses within a longitudinal databank, matching up to 20 controls for age, sex, and time of cohort entry to each patient with stroke. Conditional logistic regression was performed as an estimate of the relative risk of stroke in RA patients compared with those with noninflammatory rheumatic disorders, and to examine severity and anti–tumor necrosis factor (anti-TNF) treatment effects in RA. Results We identified 269 patients with first-ever all-category strokes and 67 with ischemic stroke, including 41 in RA patients. The odds ratio (OR) for the risk of all-category stroke in RA was 1.64 (95% confidence interval [95% CI] 1.16–2.30, P = 0.005), and for ischemic stroke was 2.66 (95% CI 1.24–5.70, P = 0.012). Ischemic stroke was predicted by hypertension, myocardial infarction, low-dose aspirin, comorbidity score, Health Assessment Questionnaire score, and presence of total joint replacement, but not by diabetes, smoking, exercise, or body mass index. Adjusted for cardiovascular and RA risk factors, ischemic stroke was associated with rofecoxib (P = 0.060, OR 2.27 [95% CI 0.97–5.28]), and possibly with corticosteroid use. Anti-TNF therapy was not associated with ischemic stroke (P = 0.584, OR 0.80 [95% CI 0.34–1.82]). Conclusion RA is associated with increased risk of stroke, particularly ischemic stroke. Stroke is predicted by RA severity, certain cardiovascular risk factors, and comorbidity. Except for rofecoxib, RA treatment does not appear to be associated with stroke, although the effect of corticosteroids remains uncertain. PMID:18668583

Risk and protective factors for suicide among patients with methamphetamine dependence: a nested case-control study.

PubMed

Kuo, Chian-Jue; Tsai, Shang-Ying; Liao, Ya-Tang; Conwell, Yeates; Lin, Shih-Ku; Chang, Chia-Ling; Chen, Chiao-Chicy; Chen, Wei J

2011-04-01

Methamphetamine as a recreational drug has undergone cycles of popularity, with a recent surge worldwide since the 1990s. This study aimed to identify clinical characteristics associated with suicide mortality in patients with methamphetamine dependence by means of a nested case-control design. In a consecutive series of 1,480 inpatients with methamphetamine dependence (diagnosed according to DSM-III-R and DSM-IV criteria) admitted to a psychiatric center in northern Taiwan from January 1, 1990, through December 31, 2006, 38 deaths due to suicide were identified as cases via record linkage, and 76 controls were randomly selected using risk-set density sampling in a 2:1 ratio, matched for age, sex, and the year of index admission. A standardized chart review process was adopted to collate sociodemographic and clinical information for each study subject. Multivariate conditional logistic regression analysis was used to identify correlates of suicide among these patients. For the sociodemographic and symptom profiles at the latest admission, financial independence lowered the risk for suicide (adjusted risk ratio [ARR] = 0.33, P < .05), whereas visual hallucinations elevated the risk (ARR = 2.57, P < .05) for suicide. For the profiles during the postdischarge period, financial independence (ARR = 0.11, P < .05) remained associated with reduced risk for suicide, whereas suicide attempt (ARR = 8.78, P < .05) and depressive syndrome (ARR = 3.28, P = .059) were associated with increased risk of suicide. Both protective and risk factors for suicide mortality were found among inpatients with methamphetamine dependence, and the findings have implications for clinical intervention and prevention. © Copyright 2011 Physicians Postgraduate Press, Inc.

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.

Case-control study of male germ cell tumors nested in a cohort of car-manufacturing workers: Findings from the occupational history.

PubMed

Langner, Ingo; Schmeisser, Nils; Mester, Birte; Behrens, Thomas; Gottlieb, Andrea; Ahrens, Wolfgang

2010-10-01

To examine whether the previously observed excess risk of male germ cell cancer in a cohort of car-manufacturing workers can be attributed to occupational activities inside and/or outside the car industry. A nested case-control study among workers in six plants included 205 cases of germ cell cancer and 1,105 controls, individually matched by year of birth (±2 years). Job periods of the individual occupational histories were coded based on the International Standard Classification of Occupations (ISCO) and the industrial classification of economic activities (NACE). Odds ratios (ORs) and corresponding 95%-confidence intervals (CI) for ever-never and cumulative employment were calculated by conditional multivariate logistic regression adjusted for cryptorchidism. Significantly increased risks were observed for machinery fitters and assemblers (A) (OR = 1.8, 95% CI 1.25-2.53) and "workers not elsewhere classified" (OR = 2.10, 95% CI 1.27-3.54), but no trend was observed for employment duration in either occupational group. Stratification of job group A by metal-cutting and non-cutting jobs yielded ORs of 1.87 (95% CI 1.31-2.67) and of 1.24 (95% CI 0.68-2.28), respectively. Among "plumbers, welders, sheet & structural metal workers" (adjusted OR 1.4, 95% CI 0.99-1.95) only "structural metal preparers and erectors" showed a substantially increased risk (OR = 2.30; 95% CI 1.27-4.27). Our results do not fully explain the increased incidence of germ cell cancer in the cohort, but support previous findings showing increased risks among metal workers. These risks were most strongly pronounced in metal-cutting activities. © 2010 Wiley-Liss, Inc.

Plasma 25-hydroxyvitamin D3 is associated with decreased risk of postmenopausal breast cancer in whites: a nested case-control study in the multiethnic cohort study.

PubMed

Kim, Yeonju; Franke, Adrian A; Shvetsov, Yurii B; Wilkens, Lynne R; Cooney, Robert V; Lurie, Galina; Maskarinec, Gertraud; Hernandez, Brenda Y; Le Marchand, Loïc; Henderson, Brian E; Kolonel, Laurence N; Goodman, Marc T

2014-01-17

Higher sunlight exposure is correlated with lower incidence of breast cancer in ecological studies, but findings from prospective studies regarding the association of circulating levels of vitamin D with the risk of breast cancer have been null. The objective of this study was to examine the relation between plasma levels of vitamin D and the risk of postmenopausal breast cancer. We conducted a nested case-control study within the Multiethnic Cohort Study of five race/ethnic groups (white, African-American, Native Hawaiian, Japanese, and Latino) from Hawaii and Los Angeles between 2001 and 2006. Pre-diagnostic plasma levels of 25-hydroxyvitamin D2 [25(OH)D2], 25-hydroxyvitamin D3 [25(OH)D3] and 25(OH)D (sum of 25(OH)D2 and 25(OH)D3) were examined among 707 postmenopausal breast cancer cases and matched controls. Using conditional logistic regression models, 20 ng/mL increases of plasma 25(OH)D3 (odds ratio (OR) 0.28; 95% confidence interval (CI) 0.14-0.56) and 25(OH)D (OR 0.43; 95% CI 0.23-0.80) were inversely associated with breast cancer risk among white women, but not among women in other race/ethnic groups. Using two-segmented, piecewise-linear logistic regression models, the change-points of the ORs, either for 25(OH)D3 or for 25(OH)D, were detected as 20 ng/mL among whites. Circulating 25(OH)D3 and 25(OH)D were associated with a reduced risk of postmenopausal breast cancer among whites, but not in other ethnic groups, who reside in low latitude regions.

Risk of Gambling Disorder and Impulse Control Disorder With Aripiprazole, Pramipexole, and Ropinirole: A Pharmacoepidemiologic Study.

PubMed

Etminan, Mahyar; Sodhi, Mohit; Samii, Ali; Procyshyn, Ric M; Guo, Michael; Carleton, Bruce C

2017-02-01

Recently, the US Food and Drug Administration issued a warning regarding the potential risk of gambling disorder, but large epidemiologic studies are lacking. We used a large health claims database from the United States and conducted a nested case-control study. Cases were defined as subjects newly diagnosed with gambling disorder or impulse control disorder. For each case, 10 controls were selected and matched to cases by age and follow-up time and calendar time. Adjusted rate ratios were computed with conditional logistic regression. There are 355 cases of gambling disorder and 3550 controls along with 4341 cases of impulse control disorder and 43,410 corresponding controls. After adjusting for confounders, users of aripiprazole demonstrated an increased risk of pathologic gambling (rate ratio [RR], 5.23; 95% confidence interval [CI], 1.78-15.38) and impulse control disorder (RR, 7.71; 95% CI, 5.81-10.34). The risk was also elevated for pramipexole or ropinirole for both gambling disorder and impulse control disorder (RR, 7.61; 95% CI, 2.75-21.07; RR, 3.28; 95% CI, 2.31-4.66, respectively). Our study confirms an association between aripiprazole, pramipexole, or ropinirole and impulse control disorder and gambling disorder.

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

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.

Increasing maternal percentage body fat in early second trimester: a risk factor for preeclampsia.

PubMed

Wang, Yanxia; Qiu, Jie; Zhou, Min; Wang, Youjie; Du, Yukai

2015-02-01

To determine if maternal percentage body fat (PBF) or fat free mass (FFM) in the early second trimester of pregnancy influenced the development of preeclampsia. A matched nested case-control study was conducted from a cohort study of 1668 women at Gansu provincial maternal and child care hospital from July 2007 to August 2011 in China. Maternal PBF and FFM were assessed by bioelectrical impedance analysis during 12th-16th gestational week. The demographic characteristics were all chart abstracted. After childbirth, 70 cases of preeclampsia were matched by race/age with 140 uncomplicated pregnancies women. Multivariate logistic regression analysis was performed to determine the associated risk factors. Pre-pregnancy body mass index were higher in women who subsequently developed preeclampsia compared with controls (p < 0.001). During 12th-16th gestational week, there were nearly 7-fold increase in the odds of preeclampsia (adjusted OR: 6.84, 95% CI: 4.15-41.60) among women with PBF ≥ 40% versus women with PBF < 40%. But FFM were not at further increased risk of the development of preeclampsia (adjusted OR, 1.02; 95% CI, 0.6-3.6). Maternal PBF but not FFM is a predictor of preeclampsia in the early second trimester. Excessive adipose tissue possibly played an important role in developing of preeclampsia.

The Ukrainian-American Study of Leukemia and Related Disorders Among Chornobyl Cleanup Workers from Ukraine: I. STUDY METHODS

PubMed Central

Romanenko, A.; Bebeshko, V; Hatch, M; Bazyka, D; Finch, S.; Dyagil, I; Reiss, R.; Chumak, V; Bouville, A; Gudzenko, N; Zablotska, L; Pilinskaya, M.; Lyubarets, T.; Bakhanova, E.; Babkina, N.; Trotsiuk, N.; Ledoschuk, B.; Belayev, Y.; Dybsky, S.S.; Ron, E.; Howe, G.

2010-01-01

Thus far there are relatively few data on the risk of leukemia among those who were exposed to external radiation during cleanup operations following the Chornobyl nuclear accident, and results have not been consistent. To investigate this issue further, we assembled a cohort of 110,645 male cleanup workers from Ukraine and identified cases of leukemia occurring during the period 1986 to 2000. Detailed interviews were conducted and individual bone marrow doses were estimated using a new time-and-motion method known as RADRUE (Realistic Analytical Dose Reconstruction with Uncertainty Estimate). See companion paper II for a detailed description of the dosimetry. For the initial analyses we used a nested case-control approach with a minimum of five controls per case, matched for year of birth, oblast (region) of registration and residence. All identified cases were reviewed by an international panel of experts. The dose-response analysis and results are given in companion paper III. PMID:19138036

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

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

Determinants of first trimester attendance at antenatal care clinics in the Amazon region of Peru: A case-control study

PubMed Central

Moore, Nora; Blouin, Brittany; Razuri, Hugo; Casapia, Martin; Gyorkos, Theresa W.

2017-01-01

Objective To identify determinants which influence the timing of the first antenatal care (ANC) visit in pregnant women. Design Retrospective matched nested case-control study. Setting Two health centres, Belén and 6 de Octubre, in the Peruvian Amazon. Population All pregnant women who had attended ANC during the years 2010, 2011, and 2012. Methods All cases (819 women initiating ANC in their first trimester) were selected from ANC registries from 2010 to 2012. A random sample of controls (819 women initiating ANC in their second or third trimester) was matched 1:1 to cases on health centre and date of first ANC visit. Data were obtained from ANC registries. Conditional logistic regression analyses were performed. Main outcome measure Case-control status of each woman determined by the gestational age at first ANC visit. Results Cases had higher odds of: 1) being married or cohabiting (aOR = 1.69; 95% CI: 1.19, 2.41); 2) completing secondary school or attending post-secondary school (aOR = 1.45; 95% CI: 1.02, 2.06); 3) living in an urban environment (aOR = 1.79; 95% CI: 1.04, 3.10) and 4) having had a previous miscarriage (aOR = 1.56; 95% CI: 1.13, 2.15), compared to controls. No statistically significant difference in odds was found for parity (aOR = 1.08; 95% CI: 0.85, 1.36). Conclusions This study provides empirical evidence of determinants of first ANC attendance. These findings are crucial to the planning and timing of local interventions, like deworming, aimed at pregnant women so that they can access and benefit fully from all government-provided ANC services. PMID:28207749

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

Determinants of first trimester attendance at antenatal care clinics in the Amazon region of Peru: A case-control study.

PubMed

Moore, Nora; Blouin, Brittany; Razuri, Hugo; Casapia, Martin; Gyorkos, Theresa W

2017-01-01

To identify determinants which influence the timing of the first antenatal care (ANC) visit in pregnant women. Retrospective matched nested case-control study. Two health centres, Belén and 6 de Octubre, in the Peruvian Amazon. All pregnant women who had attended ANC during the years 2010, 2011, and 2012. All cases (819 women initiating ANC in their first trimester) were selected from ANC registries from 2010 to 2012. A random sample of controls (819 women initiating ANC in their second or third trimester) was matched 1:1 to cases on health centre and date of first ANC visit. Data were obtained from ANC registries. Conditional logistic regression analyses were performed. Case-control status of each woman determined by the gestational age at first ANC visit. Cases had higher odds of: 1) being married or cohabiting (aOR = 1.69; 95% CI: 1.19, 2.41); 2) completing secondary school or attending post-secondary school (aOR = 1.45; 95% CI: 1.02, 2.06); 3) living in an urban environment (aOR = 1.79; 95% CI: 1.04, 3.10) and 4) having had a previous miscarriage (aOR = 1.56; 95% CI: 1.13, 2.15), compared to controls. No statistically significant difference in odds was found for parity (aOR = 1.08; 95% CI: 0.85, 1.36). This study provides empirical evidence of determinants of first ANC attendance. These findings are crucial to the planning and timing of local interventions, like deworming, aimed at pregnant women so that they can access and benefit fully from all government-provided ANC services.

Bee species-specific nesting material attracts a generalist parasitoid: implications for co-occurring bees in nest box enhancements.

PubMed

Macivor, J Scott; Salehi, Baharak

2014-08-01

Artificial nests (e.g., nest boxes) for bees are increasingly being used to contribute to nesting habitat enhancement for bees that use preexisting cavities to provision brood. They usually incorporate additional nesting materials that vary by species. Cavity-nesting bees are susceptible to brood parasitoids that recognize their host(s) using visual and chemical cues. Understanding the range of cues that attract parasitoids to bee nests, including human-made analogues, is important if we wish to control parasitism and increase the potential value of artificial nests as habitat-enhancement strategies. In this study, we investigated the cues associated with the orientation of the generalist brood parasitoid Monodontomerus obscurus Westwood (Hymenoptera: Torymidae) to the nests of a common cavity-nesting resin bee Megachile campanulae (Robertson) (Megachilidae). The parasitoids were reared from previously infested M. campanulae brood cells and placed into choice trials where they were presented with pairs of different nest material cues. Among different materials tested, we found that Mo. obscurus was most attracted to fresh resin collected directly from Pinus strobus trees followed by previously used resin collected from the bee nest. The parasitoid also attacked other bee species in the same nest boxes, including those that do not use resin for nesting. Our findings suggest that M. campanulae could act as a magnet, drawing parasites away from other bee hosts co-occurring in nest boxes, or, as an attractant of Mo. obscurus to nest boxes, increasing attacks on co-occurring host bee species, potentially undermining bee diversity enhancement initiatives.

Modeling the effects of climate change-induced shifts in reproductive phenology on temperature-dependent traits.

PubMed

Telemeco, Rory S; Abbott, Karen C; Janzen, Fredric J

2013-05-01

By altering phenology, organisms have the potential to match life-history events with suitable environmental conditions. Because of this, phenological plasticity has been proposed as a mechanism whereby populations might buffer themselves from climate change. We examine the potential buffering power of advancing one aspect of phenology, nesting date, on sex ratio in painted turtles (Chrysemys picta), a species with temperature-dependent sex determination. We developed a modified constant temperature equivalent model that accounts for the effect of the interaction among climate change, oviposition date, and seasonal thermal pattern on temperature during sexual differentiation and thus on offspring sex ratio. Our results suggest that females will not be able to buffer their progeny from the negative consequences of climate change by adjusting nesting date alone. Not only are offspring sex ratios predicted to become 100% female, but our model suggests that many nests will fail. Because the seasonal thermal trends that we consider are experienced by most temperate species, our result that adjusting spring phenology alone will be insufficient to counter the effects of directional climate change may be broadly applicable.

The NEST Dry-Run Mode: Efficient Dynamic Analysis of Neuronal Network Simulation Code.

PubMed

Kunkel, Susanne; Schenck, Wolfram

2017-01-01

NEST is a simulator for spiking neuronal networks that commits to a general purpose approach: It allows for high flexibility in the design of network models, and its applications range from small-scale simulations on laptops to brain-scale simulations on supercomputers. Hence, developers need to test their code for various use cases and ensure that changes to code do not impair scalability. However, running a full set of benchmarks on a supercomputer takes up precious compute-time resources and can entail long queuing times. Here, we present the NEST dry-run mode, which enables comprehensive dynamic code analysis without requiring access to high-performance computing facilities. A dry-run simulation is carried out by a single process, which performs all simulation steps except communication as if it was part of a parallel environment with many processes. We show that measurements of memory usage and runtime of neuronal network simulations closely match the corresponding dry-run data. Furthermore, we demonstrate the successful application of the dry-run mode in the areas of profiling and performance modeling.

The NEST Dry-Run Mode: Efficient Dynamic Analysis of Neuronal Network Simulation Code

PubMed Central

Kunkel, Susanne; Schenck, Wolfram

2017-01-01

NEST is a simulator for spiking neuronal networks that commits to a general purpose approach: It allows for high flexibility in the design of network models, and its applications range from small-scale simulations on laptops to brain-scale simulations on supercomputers. Hence, developers need to test their code for various use cases and ensure that changes to code do not impair scalability. However, running a full set of benchmarks on a supercomputer takes up precious compute-time resources and can entail long queuing times. Here, we present the NEST dry-run mode, which enables comprehensive dynamic code analysis without requiring access to high-performance computing facilities. A dry-run simulation is carried out by a single process, which performs all simulation steps except communication as if it was part of a parallel environment with many processes. We show that measurements of memory usage and runtime of neuronal network simulations closely match the corresponding dry-run data. Furthermore, we demonstrate the successful application of the dry-run mode in the areas of profiling and performance modeling. PMID:28701946

Pro-social behaviour of ants depends on their ecological niche-Rescue actions in species from tropical and temperate regions.

PubMed

Miler, Krzysztof; Yahya, Bakhtiar Effendi; Czarnoleski, Marcin

2017-11-01

Some ants display rescue behaviour, which is performed by nearby nestmates and directed at individuals in danger. Here, using several ant species, we demonstrate that rescue behaviour expression matches predicted occurrences based on certain aspects of species' ecological niches. Rescue occurred in sand-dwelling ants exposed both to co-occurring antlion larvae, representing the threat of being captured by a predator, and to nest cave-ins, representing the threat of being trapped in a collapsed nest chamber. Rescue also occurred in forest groundcover ants exposed to certain entrapment situations. However, rescue never occurred in species associated with open plains, which nest in hardened soils and forage largely on herbaceous plants, or in ants living in close mutualistic relationships with their host plants. In addition, because we tested each species in two types of tests, antlion larva capture tests and artificial entrapment tests, we highlight the importance of accounting for test context in studying rescue behaviour expression. Copyright © 2017 Elsevier B.V. All rights reserved.

Dual-mode nested search method for categorical uncertain multi-objective optimization

NASA Astrophysics Data System (ADS)

Tang, Long; Wang, Hu

2016-10-01

Categorical multi-objective optimization is an important issue involved in many matching design problems. Non-numerical variables and their uncertainty are the major challenges of such optimizations. Therefore, this article proposes a dual-mode nested search (DMNS) method. In the outer layer, kriging metamodels are established using standard regular simplex mapping (SRSM) from categorical candidates to numerical values. Assisted by the metamodels, a k-cluster-based intelligent sampling strategy is developed to search Pareto frontier points. The inner layer uses an interval number method to model the uncertainty of categorical candidates. To improve the efficiency, a multi-feature convergent optimization via most-promising-area stochastic search (MFCOMPASS) is proposed to determine the bounds of objectives. Finally, typical numerical examples are employed to demonstrate the effectiveness of the proposed DMNS method.

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.

Terrestrial nest-building by wild chimpanzees (Pan troglodytes): implications for the tree-to-ground sleep transition in early hominins.

PubMed

Koops, Kathelijne; McGrew, William C; Matsuzawa, Tetsuro; Knapp, Leslie A

2012-07-01

Nest-building is a great ape universal and arboreal nesting in chimpanzees and bonobos suggests that the common ancestor of Pan and Homo also nested in trees. It has been proposed that arboreal nest-building remained the prevailing pattern until Homo erectus, a fully terrestrial biped, emerged. We investigated the unusual occurrence of ground-nesting in chimpanzees (Pan troglodytes), which may inform on factors influencing the tree-to-ground sleep transition in the hominin lineage. We used a novel genetic approach to examine ground-nesting in unhabituated chimpanzees at Seringbara in the Nimba Mountains, Guinea. Previous research showed that ground-nesting at Seringbara was not ecologically determined. Here, we tested a possible mate-guarding function of ground-nesting by analyzing DNA from shed hairs collected from ground nests and tree nests found in close proximity. We examined whether or not ground-nesting was a group-level behavioral pattern and whether or not it occurred in more than one community. We used multiple genetic markers to identify sex and to examine variation in mitochondrial DNA control region (HV1, HV2) sequences. Ground-nesting was a male-biased behavior and males constructed more elaborate ("night") nests than simple ("day") nests on the ground. The mate-guarding hypothesis was not supported, as ground and associated tree nests were built either by maternally-related males or possibly by the same individuals. Ground-nesting was widespread and likely habitual in two communities. We suggest that terrestrial nest-building may have already occurred in arboreally-adapted early hominins before the emergence of H. erectus. Copyright © 2012 Wiley Periodicals, Inc.

Nest construction by a ground-nesting bird represents a potential trade-off between egg crypticity and thermoregulation.

PubMed

Mayer, Paul M; Smith, Levica M; Ford, Robert G; Watterson, Dustin C; McCutchen, Marshall D; Ryan, Mark R

2009-04-01

Predation selects against conspicuous colors in bird eggs and nests, while thermoregulatory constraints select for nest-building behavior that regulates incubation temperatures. We present results that suggest a trade-off between nest crypticity and thermoregulation of eggs based on selection of nest materials by piping plovers (Charadrius melodus), a ground-nesting bird that constructs simple, pebble-lined nests highly vulnerable to predators and exposed to temperature extremes. Piping plovers selected pebbles that were whiter and appeared closer in color to eggs than randomly available pebbles, suggesting a crypsis function. However, nests that were more contrasting in color to surrounding substrates were at greater risk of predation, suggesting an alternate strategy driving selection of white rocks. Near-infrared reflectance of nest pebbles was higher than randomly available pebbles, indicating a direct physical mechanism for heat control through pebble selection. Artificial nests constructed of randomly available pebbles heated more quickly and conferred heat to model eggs, causing eggs to heat more rapidly than in nests constructed from piping plover nest pebbles. Thermal models and field data indicated that temperatures inside nests may remain up to 2-6 degrees C cooler than surrounding substrates. Thermal models indicated that nests heat especially rapidly if not incubated, suggesting that nest construction behavior may serve to keep eggs cooler during the unattended laying period. Thus, pebble selection suggests a potential trade-off between maximizing heat reflectance to improve egg microclimate and minimizing conspicuous contrast of nests with the surrounding substrate to conceal eggs from predators. Nest construction behavior that employs light-colored, thermally reflective materials may represent an evolutionary response by birds and other egg-laying organisms to egg predation and heat stress.

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.

Unforeseen effects of supplementary feeding: ungulate baiting sites as hotspots for ground-nest predation.

PubMed

Selva, Nuria; Berezowska-Cnota, Teresa; Elguero-Claramunt, Isabel

2014-01-01

Despite the ubiquity and magnitude of food provision to wildlife, our understanding of its ecological effects and conservation implications is very limited. Supplementary feeding of ungulates, still one of the main paradigms of game management in Europe, occurs in natural areas on an enormous scale. We investigated the indirect effects of this practice on nest predation risk in the Polish Eastern Carpathians (Bieszczady Mountains). We hypothesized that the predators attracted to ungulate baiting sites would also forage for alternative prey nearby, increasing the nest predation risk for ground-nesting birds in the vicinity. We conducted a paired experiment by placing artificial nests (N=120) in feeding and control sites (N=12) at different distances from the ungulate feeding site. We also documented the use of three ungulate feeding sites by potential nest predators with automatic cameras. The proportion of depredated nests was 30% higher in the vicinity of feeding sites than at control sites (65%± 31.5 vs 35%± 32.1). The probability of a nest being depredated significantly increased with time and at shorter distances from the feeding site. We predicted that the area within 1-km distance from the feeding site would have a high risk (>0.5) of nest predation. We recorded 13 species of potential ground-nest predators at ungulate baiting sites. Most frequent were Eurasian jays Garrulus glandarius, mice and voles Muroidea, ravens Corvus corax, brown bears Ursus arctos, and wild boar Sus scrofa. Nest predators made most use of supplementary feeding sites (82% pictures with predators vs 8% with ungulates, the target group). Our study alerts of the impacts of ungulate feeding on alternative prey; this is of special concern when affecting protected species. We urge for a sensible management of ungulate feeding, which considers potential indirect effects on other species and the spatial and temporal components of food provision.

Biomarkers and Bacterial Pneumonia Risk in Patients with Treated HIV Infection: A Case-Control Study

PubMed Central

Bjerk, Sonja M.; Baker, Jason V.; Emery, Sean; Neuhaus, Jacqueline; Angus, Brian; Gordin, Fred M.; Pett, Sarah L.; Stephan, Christoph; Kunisaki, Ken M.

2013-01-01

Background Despite advances in HIV treatment, bacterial pneumonia continues to cause considerable morbidity and mortality in patients with HIV infection. Studies of biomarker associations with bacterial pneumonia risk in treated HIV-infected patients do not currently exist. Methods We performed a nested, matched, case-control study among participants randomized to continuous combination antiretroviral therapy (cART) in the Strategies for Management of Antiretroviral Therapy trial. Patients who developed bacterial pneumonia (cases) and patients without bacterial pneumonia (controls) were matched 1∶1 on clinical center, smoking status, age, and baseline cART use. Baseline levels of Club Cell Secretory Protein 16 (CC16), Surfactant Protein D (SP-D), C-reactive protein (hsCRP), interleukin-6 (IL-6), and d-dimer were compared between cases and controls. Results Cases (n = 72) and controls (n = 72) were 25.7% female, 51.4% black, 65.3% current smokers, 9.7% diabetic, 36.1% co-infected with Hepatitis B/C, and 75.0% were on cART at baseline. Median (IQR) age was 45 (41, 51) years with CD4+ count of 553 (436, 690) cells/mm3. Baseline CC16 and SP-D were similar between cases and controls, but hsCRP was significantly higher in cases than controls (2.94 µg/mL in cases vs. 1.93 µg/mL in controls; p = 0.02). IL-6 and d-dimer levels were also higher in cases compared to controls, though differences were not statistically significant (p-value 0.06 and 0.10, respectively). Conclusions In patients with cART-treated HIV infection, higher levels of systemic inflammatory markers were associated with increased bacterial pneumonia risk, while two pulmonary-specific inflammatory biomarkers, CC16 and SP-D, were not associated with bacterial pneumonia risk. PMID:23457535

Geographic variation in avian incubation periods and parental influences on embryonic temperature

USGS Publications Warehouse

Martin, T.E.; Auer, S.K.; Bassar, R.D.; Niklison, Alina M.; Lloyd, P.

2007-01-01

Theory predicts shorter embryonic periods in species with greater embryo mortality risk and smaller body size. Field studies of 80 passerine species on three continents yielded data that largely conflicted with theory; incubation (embryonic) periods were longer rather than shorter in smaller species, and egg (embryo) mortality risk explained some variation within regions, but did not explain larger differences in incubation periods among geographic regions. Incubation behavior of parents seems to explain these discrepancies. Bird embryos are effectively ectothermic and depend on warmth provided by parents sitting on the eggs to attain proper temperatures for development. Parents of smaller species, plus tropical and southern hemisphere species, commonly exhibited lower nest attentiveness (percent of time spent on the nest incubating) than larger and northern hemisphere species. Lower nest attentiveness produced cooler minimum and average embryonic temperatures that were correlated with longer incubation periods independent of nest predation risk or body size. We experimentally tested this correlation by swapping eggs of species with cool incubation temperatures with eggs of species with warm incubation temperatures and similar egg mass. Incubation periods changed (shortened or lengthened) as expected and verified the importance of egg temperature on development rate. Slower development resulting from cooler temperatures may simply be a cost imposed on embryos by parents and may not enhance offspring quality. At the same time, incubation periods of transferred eggs did not match host species and reflect intrinsic differences among species that may result from nest predation and other selection pressures. Thus, geographic variation in embryonic development may reflect more complex interactions than previously recognized. ?? 2007 The Author(s).

Nesting characteristics of mourning doves in central New Mexico: Response to riparian forest change

Treesearch

D. Max Smith; Deborah M. Finch; David L. Hawksworth

2012-01-01

Riparian forests of the American Southwest are especially prone to changes in composition and structure due to natural and anthropogenic factors. To determine how breeding mourning doves (Zenaida macroura) respond to these changes, we examined nest site use and nest survival in control plots, fuel reduction plots before and after mechanical thinning, and post-wildfire...

Light pollution disrupts sleep in free-living animals.

PubMed

Raap, Thomas; Pinxten, Rianne; Eens, Marcel

2015-09-04

Artificial lighting can alter individual behaviour, with often drastic and potentially negative effects on biological rhythms, daily activity and reproduction. Whether this is caused by a disruption of sleep, an important widespread behaviour enabling animals to recover from daily stress, is unclear. We tested the hypothesis that light pollution disrupts sleep by recording individual sleep behaviour of great tits, Parus major, that were roosting in dark nest-boxes and were exposed to light-emitting diode light the following night. Their behaviour was compared to that of control birds sleeping in dark nest-boxes on both nights. Artificial lighting caused experimental birds to wake up earlier, sleep less (-5%) and spent less time in the nest-box as they left their nest-box earlier in the morning. Experimental birds did not enter the nest-box or fall asleep later than controls. Although individuals in lit nest-boxes did not wake up more often nor decreased the length of their sleep bouts, females spent a greater proportion of the night awake. Our study provides the first direct proof that light pollution has a significant impact on sleep in free-living animals, in particular in the morning, and highlights a mechanism for potential effects of light pollution on fitness.

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

Study design: Evaluating gene–environment interactions in the etiology of breast cancer – the WECARE study

PubMed Central

Bernstein, Jonine L; Langholz, Bryan; Haile, Robert W; Bernstein, Leslie; Thomas, Duncan C; Stovall, Marilyn; Malone, Kathleen E; Lynch, Charles F; Olsen, Jørgen H; Anton-Culver, Hoda; Shore, Roy E; Boice, John D; Berkowitz, Gertrud S; Gatti, Richard A; Teitelbaum, Susan L; Smith, Susan A; Rosenstein, Barry S; Børresen-Dale, Anne-Lise; Concannon, Patrick; Thompson, W Douglas

2004-01-01

Introduction Deficiencies in cellular responses to DNA damage can predispose to cancer. Ionizing radiation can cause cluster damage and double-strand breaks (DSBs) that pose problems for cellular repair processes. Three genes (ATM, BRCA1, and BRCA2) encode products that are essential for the normal cellular response to DSBs, but predispose to breast cancer when mutated. Design To examine the joint roles of radiation exposure and genetic susceptibility in the etiology of breast cancer, we designed a case-control study nested within five population-based cancer registries. We hypothesized that a woman carrying a mutant allele in one of these genes is more susceptible to radiation-induced breast cancer than is a non-carrier. In our study, 700 women with asynchronous bilateral breast cancer were individually matched to 1400 controls with unilateral breast cancer on date and age at diagnosis of the first breast cancer, race, and registry region, and counter-matched on radiation therapy. Each triplet comprised two women who received radiation therapy and one woman who did not. Radiation absorbed dose to the contralateral breast after initial treatment was estimated with a comprehensive dose reconstruction approach that included experimental measurements in anthropomorphic and water phantoms applying patient treatment parameters. Blood samples were collected from all participants for genetic analyses. Conclusions Our study design improves the potential for detecting gene–environment interactions for diseases when both gene mutations and the environmental exposures of interest are rare in the general population. This is particularly applicable to the study of bilateral breast cancer because both radiation dose and genetic susceptibility have important etiologic roles, possibly by interactive mechanisms. By using counter-matching, we optimized the informativeness of the collected dosimetry data by increasing the variability of radiation dose within the case–control sets and enhanced our ability to detect radiation–genotype interactions. PMID:15084244

Nesting behaviour influences species-specific gas exchange across avian eggshells.

PubMed

Portugal, Steven J; Maurer, Golo; Thomas, Gavin H; Hauber, Mark E; Grim, Tomáš; Cassey, Phillip

2014-09-15

Carefully controlled gas exchange across the eggshell is essential for the development of the avian embryo. Water vapour conductance (G(H2O)) across the shell, typically measured as mass loss during incubation, has been demonstrated to optimally ensure the healthy development of the embryo while avoiding desiccation. Accordingly, eggs exposed to sub-optimal gas exchange have reduced hatching success. We tested the association between eggshell G(H2O) and putative life-history correlates of adult birds, ecological nest parameters and physical characteristics of the egg itself to investigate how variation in G(H2O) has evolved to maintain optimal water loss across a diverse set of nest environments. We measured gas exchange through eggshell fragments in 151 British breeding bird species and fitted phylogenetically controlled, general linear models to test the relationship between G(H2O) and potential predictor parameters of each species. Of our 17 life-history traits, only two were retained in the final model: wet-incubating parent and nest type. Eggs of species where the parent habitually returned to the nest with wet plumage had significantly higher G(H2O) than those of parents that returned to the nest with dry plumage. Eggs of species nesting in ground burrows, cliffs and arboreal cups had significantly higher G(H2O) than those of species nesting on the ground in open nests or cups, in tree cavities and in shallow arboreal nests. Phylogenetic signal (measured as Pagel's λ) was intermediate in magnitude, suggesting that differences observed in the G(H2O) are dependent upon a combination of shared ancestry and species-specific life history and ecological traits. Although these data are correlational by nature, they are consistent with the hypothesis that parents constrained to return to the nest with wet plumage will increase the humidity of the nest environment, and the eggs of these species have evolved a higher G(H2O) to overcome this constraint and still achieve optimal water loss during incubation. We also suggest that eggs laid in cup nests and burrows may require a higher G(H2O) to overcome the increased humidity as a result from the confined nest microclimate lacking air movements through the nest. Taken together, these comparative data imply that species-specific levels of gas exchange across avian eggshells are variable and evolve in response to ecological and physical variation resulting from parental and nesting behaviours. © 2014. Published by The Company of Biologists Ltd.

Family characteristics have limited ability to predict weight status of young children.

PubMed

Gray, Virginia B; Byrd, Sylvia H; Cossman, Jeralynn S; Chromiak, Joseph; Cheek, Wanda K; Jackson, Gary B

2007-07-01

The ability of (a) family characteristics (marital status, income, race, and education), (b) parental control over child's food intake, and (c) parental belief in causes of overweight to predict weight status of children was assessed. Parents/caretakers of elementary school-aged children were surveyed to determine attitudes related to childhood nutrition and overweight. Anthropometric measurements were obtained from children to determine weight status (n=169 matched surveys and measurements). chi(2) tests and nested logistic regression models were used to determine relationships between children's weight status and family characteristics, parental control, and parental belief in the primary cause of overweight. Low household income was an important predictor of overweight; marital status and race added no further explanatory power to the model. Parental control was not a significant predictor of overweight. Parental belief in the primary cause of overweight in children (diet vs physical activity) was significantly related to children's weight; however, it was not significant after controlling for income. Low household income relates strongly to increased childhood weight status; therefore, school and government policies should promote an environment that supports affordable, safe, and feasible opportunities for healthful nutrition and physical activity, particularly for low-income audiences.

Collecting a sample of loggerhead sea turtle hatchlings before a natural emergence does not reduce nest productivity

USGS Publications Warehouse

Salmon, Michael; Carthy, Raymond R.; Lohmann, Catherine M. F.; Lohmann, Kenneth J.; Wyneken, Jeanette

2012-01-01

 In numerous studies involving hatchling sea turtles, researchers have collected small numbers of hatchlings from nests a few hours before the turtles would otherwise have emerged naturally. This procedure makes it possible to do experiments in which the behavioral or physiological responses of numerous hatchlings must be tested in a limited period of time, and also allows hatchlings to be released back into the sea in time to migrate offshore before dawn. In principle, however, the procedure might inadvertently reduce nest productivity (the number of hatchlings that successfully leave the nest), if digging into a nest prior to emergence somehow reduces the ability of the remaining turtles to emerge. We compared nest productivity in 67 experimental loggerhead nests, from which we removed 10 hatchlings before a natural emergence, to 95 control nests left undisturbed before a natural emergence. The 2 groups showed no statistical differences in productivity. We conclude that taking a few hatchlings from a loggerhead nest shortly before a natural emergence has no negative impact on hatchling production if sampling is done with care at locations where there are few nest predators, and at sites where an emergence can be predicted because nest deposition dates are known.

Temporal flexibility of reproduction in temperate-breeding dabbling ducks

USGS Publications Warehouse

Krapu, Gary L.

2000-01-01

I compared nesting intervals during three consecutive years in five species of temperate-nesting dabbling ducks (Mallard [Anas platyrhynchos], Northern Pintail [Anas acuta], Northern Shoveler [Anas clypeata], Blue-winged Teal [Anas discors], Gadwall [Anas strepera]) and assessed whether differences existed in timing of refractoriness. Most nesting by females of all five species ended by the summer solstice. Nesting ended earliest for Northern Shovelers and Northern Pintails and latest for Gadwalls. Some Mallards, Blue-winged Teal, and Gadwalls continued to nest into mid- and late summer, whereas Northern Shovelers and Northern pintails did not. Mallards, Blue-winged Teal, and Gadwalls accounted for 99% (81 of 82) of flightless broods resulting from nests initiated during mid- or late summer in North Dakota and 98% (58 of 59) of flightless juveniles shot on or after 1 October by a random sample of duck hunters from across the United States. Early cessation of breeding by Northern Shovelers may have evolved in response to the species' limited flexibility in diet. Photorefractory mechanisms that limit most breeding to spring presumably evolved in response to severe constraints on reproductive success when nesting continued through summer(e.g. mortality of late-hatched young and molting females due to low temperatures). Interspecific differences in photosensitivity may account for variation in timing of cessation of nesting in late spring, but controlled experiments are needed to assess the possible role of non-photic influences. My results suggest that the refractory mechanisms controlling length of the breeding in temperate-nesting dabbling ducks are more varied and complex than previously thought, with non-photic influences (e.g. water conditions, food availability, food quality) having a larger role than indicated by earlier research.

Impacts of tree rows on grassland birds and potential nest predators: a removal experiment.

PubMed

Ellison, Kevin S; Ribic, Christine A; Sample, David W; Fawcett, Megan J; Dadisman, John D

2013-01-01

Globally, grasslands and the wildlife that inhabit them are widely imperiled. Encroachment by shrubs and trees has widely impacted grasslands in the past 150 years. In North America, most grassland birds avoid nesting near woody vegetation. Because woody vegetation fragments grasslands and potential nest predator diversity and abundance is often greater along wooded edge and grassland transitions, we measured the impacts of removing rows of trees and shrubs that intersected grasslands on potential nest predators and the three most abundant grassland bird species (Henslow's sparrow [Ammodramus henslowii], Eastern meadowlark [Sturnella magna], and bobolink [Dolichonyx oryzivorus]) at sites in Wisconsin, U.S.A. We monitored 3 control and 3 treatment sites, for 1 yr prior to and 3 yr after tree row removal at the treatment sites. Grassland bird densities increased (2-4 times for bobolink and Henslow's sparrow) and nesting densities increased (all 3 species) in the removal areas compared to control areas. After removals, Henslow's sparrows nested within ≤50 m of the treatment area, where they did not occur when tree rows were present. Most dramatically, activity by woodland-associated predators nearly ceased (nine-fold decrease for raccoon [Procyon lotor]) at the removals and grassland predators increased (up to 27 times activity for thirteen-lined ground squirrel [Ictidomys tridecemlineatus]). Nest success did not increase, likely reflecting the increase in grassland predators. However, more nests were attempted by all 3 species (175 versus 116) and the number of successful nests for bobolinks and Henslow's sparrows increased. Because of gains in habitat, increased use by birds, greater production of young, and the effective removal of woodland-associated predators, tree row removal, where appropriate based on the predator community, can be a beneficial management action for conserving grassland birds and improving fragmented and degraded grassland ecosystems.

Hierarchically nested river landform sequences

NASA Astrophysics Data System (ADS)

Pasternack, G. B.; Weber, M. D.; Brown, R. A.; Baig, D.

2017-12-01

River corridors exhibit landforms nested within landforms repeatedly down spatial scales. In this study we developed, tested, and implemented a new way to create river classifications by mapping domains of fluvial processes with respect to the hierarchical organization of topographic complexity that drives fluvial dynamism. We tested this approach on flow convergence routing, a morphodynamic mechanism with different states depending on the structure of nondimensional topographic variability. Five nondimensional landform types with unique functionality (nozzle, wide bar, normal channel, constricted pool, and oversized) represent this process at any flow. When this typology is nested at base flow, bankfull, and floodprone scales it creates a system with up to 125 functional types. This shows how a single mechanism produces complex dynamism via nesting. Given the classification, we answered nine specific scientific questions to investigate the abundance, sequencing, and hierarchical nesting of these new landform types using a 35-km gravel/cobble river segment of the Yuba River in California. The nested structure of flow convergence routing landforms found in this study revealed that bankfull landforms are nested within specific floodprone valley landform types, and these types control bankfull morphodynamics during moderate to large floods. As a result, this study calls into question the prevailing theory that the bankfull channel of a gravel/cobble river is controlled by in-channel, bankfull, and/or small flood flows. Such flows are too small to initiate widespread sediment transport in a gravel/cobble river with topographic complexity.

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.

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

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/.

The relationship between MnSOD Val16Ala gene polymorphism and the level of serum total antioxidant capacity with the risk of chronic kidney disease in type 2 diabetic patients: a nested case-control study in the Tehran lipid glucose study.

PubMed

Abbasi, Mehrnaz; Daneshpour, Maryam S; Hedayati, Mehdi; Mottaghi, Azadeh; Pourvali, Katayoun; Azizi, Fereidoun

2018-01-01

Several studies have shown significant associations between manganese superoxide dismutase (MnSOD) Val16Ala polymorphism and diabetic complications, but this association has not been explored in relation with chronic kidney disease (CKD) in Type 2 diabetes mellitus (T2DM) patients. Total antioxidant capacity (TAC) level changes in diabetic condition and may play important role in onset or progression of the disease and its complications. The present study investigated the association of MnSOD Val16Ala polymorphism and serum TAC with the risk of CKD in T2DM patients. This nested case-control study included 280 type 2 diabetic patients with CKD and 280 age, sex and diabetes duration-matched control subjects selected from the participants of the Tehran Lipid and Glucose Study. MnSOD val16Ala (rs4880) SNP was genotyped by the Tetra-Primer ARMS-polymerase chain reaction analysis. Serum TAC was measured using ferric-reducing antioxidant power assay. Statistical analysis was performed using STATA statistical package v.12.0 or SPSS (Version 22.0). The Ala allele of the MnSOD Val16Ala polymorphism was associated with a lower risk of CKD (odds ratio (OR), 0.55; 95% confidence interval (CI), 0.36-0.84; P  = 0.006). Median serum TAC in CKD group was 920 μmol/L and was significantly lower ( p  < 0.001) compared to the control group (1045 μmol/L). Using an adjusted conditional logistic regression, we didn't observe any significant interaction between MnSOD Val16Ala SNP with quartiles of serum TAC in relation to CKD. A significant association was found between the MnSOD Val16Ala polymorphism and CKD, but this association is not affected by serum TAC level in T2DM patients.

Plasma bicarbonate and odds of incident hypertension.

PubMed

Mandel, Ernest I; Forman, John P; Curhan, Gary C; Taylor, Eric N

2013-12-01

Several biomarkers of metabolic acidosis, including lower plasma bicarbonate, have been associated with prevalent hypertension in cross-sectional studies. We sought to examine prospectively whether lower plasma bicarbonate is associated with incident hypertension. We conducted a prospective case-control study nested within the Nurses' Health Study II. Plasma bicarbonate was measured in 695 nonobese women without hypertension at time of blood draw who subsequently developed hypertension during 6 years of follow-up. Control subjects were matched to case subjects according to age, race, time and day of blood draw, and day of menstrual cycle. We used unconditional logistic regression to generate odds ratios (ORs) for development of hypertension by quintile of baseline plasma bicarbonate. After adjusting for matching factors, body mass index, family history of hypertension, plasma creatinine, and dietary and lifestyle factors, higher plasma bicarbonate was associated with lower odds of developing hypertension across quintiles (P for linear trend = 0.04). Those in the highest compared with the lowest quintile of plasma bicarbonate had 31% lower odds of developing hypertension (OR = 0.69; 95% confidence interval = 0.48-0.99). Further adjustment for diet-estimated net endogenous acid production, plasma insulin, 25-hydroxyvitamin D, and uric acid did not alter these findings. Our case-control study is consistent with a modest association between higher plasma bicarbonate and reduced odds of developing hypertension among nonobese women, although our findings are of borderline statistical significance. Further research is required to confirm this finding as part of a larger prospective cohort study and to elucidate the mechanism for this relation.

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

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.

Trajectory of cartilage loss within 4 years of knee replacement--a nested case-control study from the osteoarthritis initiative.

PubMed

Eckstein, F; Boudreau, R M; Wang, Z; Hannon, M J; Wirth, W; Cotofana, S; Guermazi, A; Roemer, F; Nevitt, M; John, M R; Ladel, C; Sharma, L; Hunter, D J; Kwoh, C K

2014-10-01

Knee replacement (KR) represents a clinically important endpoint of knee osteoarthritis (KOA). Here we examine the 4-year trajectory of femoro-tibial cartilage thickness loss prior to KR vs non-replaced controls. A nested case-control study was performed in Osteoarthritis Initiative (OAI) participants: Cases with KR between 12 and 60 month (M) follow-up were each matched with one control (without KR through 60M) by age, sex, and baseline radiographic stage. Femoro-tibial cartilage thickness was measured quantitatively using magnetic resonance imaging (MRI) at the annual visit prior to KR occurrence (T0), and at 1-4 years prior to T0 (T-1 to T-4). Cartilage loss between cases and controls was compared using paired t-tests and conditional logistic regression. One hundred and eighty-nine knees of 164 OAI participants [55% women; age 64 ± 8.7; body mass index (BMI) 29 ± 4.5] had KR and longitudinal cartilage data. Comparison of annualized slopes of change across all time points revealed greater loss in the central medial tibia (primary outcome) in KRs than in controls [94 ± 137 vs 55 ± 104 μm; P = 0.0017 (paired t); odds ratio (OR) 1.36 (95% confidence interval (CI): 1.08-1.70)]. The discrimination was stronger for T-2 → T0 [OR 1.61 (1.33-1.95), n = 127] than for T-1 → T0, and was not statistically significant for intervals prior to T-2 [i.e., T-4 → T-2, OR 0.97 (0.67-1.41), n = 60]. Results were similar for total medial femoro-tibial cartilage loss (secondary outcome), and when adjusting for pain and BMI. In knees with subsequent replacement, cartilage loss accelerates in the 2 years, and particularly in the year prior to surgery, compared with controls. Whether slowing this cartilage loss can delay KR remains to be determined. Copyright © 2014 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Effects of parents and Brown-headed Cowbirds (Molothrus ater) on nest predation risk for a songbird

PubMed Central

Latif, Quresh S; Heath, Sacha K; Rotenberry, John T

2012-01-01

Nest predation limits avian fitness, so ornithologists study nest predation, but they often only document patterns of predation rates without substantively investigating underlying mechanisms. Parental behavior and predator ecology are two fundamental drivers of predation rates and patterns, but the role of parents is less certain, particularly for songbirds. Previous work reproduced microhabitat-predation patterns experienced by Yellow Warblers (Setophaga petechia) in the Mono Lake basin at experimental nests without parents, suggesting that these patterns were driven by predator ecology rather than predator interactions with parents. In this study, we further explored effects of post-initiation parental behavior (nest defense and attendance) on predation risk by comparing natural versus experimental patterns related to territory density, seasonal timing of nest initiation, and nest age. Rates of parasitism by Brown-headed Cowbirds (Molothrus ater) were high in this system (49% nests parasitized), so we also examined parasitism-predation relationships. Natural nest predation rates (NPR) correlated negatively with breeding territory density and nonlinearly (U-shaped relationship) with nest-initiation timing, but experimental nests recorded no such patterns. After adjusting natural-nest data to control for these differences from experimental nests other than the presence of parents (e.g., defining nest failure similarly and excluding nestling-period data), we obtained similar results. Thus, parents were necessary to produce observed patterns. Lower natural NPR compared with experimental NPR suggested that parents reduced predation rates via nest defense, so this parental behavior or its consequences were likely correlated with density or seasonal timing. In contrast, daily predation rates decreased with nest age for both nest types, indicating this pattern did not involve parents. Parasitized nests suffered higher rates of partial predation but lower rates of complete predation, suggesting direct predation by cowbirds. Explicit behavioral research on parents, predators (including cowbirds), and their interactions would further illuminate mechanisms underlying the density, seasonal, and nest age patterns we observed. PMID:23301174

Development of Nested PCR-Based Specific Markers for Detection of Peach Rosette Mosaic Virus in Plant Quarantine.

PubMed

Lee, S; Kim, C S; Shin, Y G; Kim, J H; Kim, Y S; Jheong, W H

2016-03-01

The Peach rosette mosaic virus (PRMV) is a plant pathogen of the genus Nepovirus, and has been designated as a controlled quarantine virus in Korea. In this study, a specific reverse transcription (RT)-PCR marker set, nested PCR marker set, and modified-plasmid positive control were developed to promptly and accurately diagnose PRMV at plant-quarantine sites. The final selected PRMV-specific RT-PCR marker was PRMV-N10/C70 (967 bp), and the nested PCR product of 419 bp was finally amplified. The modified-plasmid positive control, in which the SalI restriction-enzyme region (GTCGAC) was inserted, verified PRMV contamination in a comparison with the control, enabling a more accurate diagnosis. It is expected that the developed method will continuously contribute to the plant-quarantine process in Korea.

Second Malignant Neoplasms in Digestive Organs After Childhood Cancer: A Cohort-Nested Case-Control Study

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

Tukenova, Markhaba; Diallo, Ibrahima; University Paris Sud 11, UMRS, Villejuif

Purpose: Cancers of the digestive system constitute a major risk for childhood cancer survivors treated with radiotherapy once they reach adulthood. The aim of this study was to determine therapy-related risk factors for the development of a second malignancy in the digestive organs (SMDO) after a childhood cancer. Methods and Materials: Among 4,568 2-year survivors of a childhood solid cancer diagnosed before 17 years of age at eight French and British centers, and among 25,120 patients diagnosed as having a malignant neoplasm before the age of 20 years, whose data were extracted from the Nordic Cancer Registries, we matched 58more » case patients (41 men and 17 women) of SMDO and 167 controls, in their respective cohort, for sex, age at first cancer, calendar year of occurrence of the first cancer, and duration of follow-up. The radiation dose received at the site of each second malignancy and at the corresponding site of its matched control was estimated. Results: The risk of developing a SMDO was 9.7-fold higher in relation to the general populations in France and the United Kingdom. In the case-control study, a strong dose-response relationship was estimated, compared with that in survivors who had not received radiotherapy; the odds ratio was 5.2 (95% CI, 1.7-16.0) for local radiation doses between 10 and 29 Gy and 9.6 (95% CI, 2.6-35.2) for doses equal to or greater than 30 Gy. Chemotherapy was also found to increase the risk of developing SMDO. Conclusions: This study confirms that childhood cancer treatments strongly increase the risk of SMDO, which occur only after a very long latency period.« less

Relationship of ZNF423 and CTSO with breast cancer risk in two randomised tamoxifen prevention trials.

PubMed

Brentnall, Adam R; Cuzick, Jack; Byers, Helen; Segal, Corrinne; Reuter, Caroline; Detre, Simone; Sestak, Ivana; Howell, Anthony; Powles, Trevor J; Newman, William G; Dowsett, Mitchell

2016-08-01

A case-control study from two randomised breast cancer prevention trials of tamoxifen and raloxifene (P-1 and P-2) identified single-nucleotide polymorphisms (SNPs) in or near genes ZNF423 and CTSO as factors which predict which women will derive most anti-cancer benefit from selective oestrogen receptor modulator (SERM) therapy. In this article, we further examine this question using blood samples from two randomised tamoxifen prevention trials: the International Breast Cancer Intervention Study I (IBIS-I) and the Royal Marsden trial (Marsden). A nested case-control study was designed with 2:1 matching in IBIS-I and 1:1 matching in Marsden. The OncoArray was used for genotyping and included two SNPs previously identified (rs8060157 in ZNF423 and rs10030044 near CTSO), and 102 further SNPs within the same regions. Overall, there were 369 cases and 662 controls, with 148 cases and 268 controls from the tamoxifen arms. Odds ratios were estimated by conditional logistic regression, with Wald 95 % confidence intervals. In the tamoxifen arms, the per-allele odds ratio for rs8060157 was 0.99 (95 %CI 0.73-1.34) and 1.00 (95 %CI 0.76-1.33) for rs10030044. In the placebo arm, the odds ratio was 1.10 (95 %CI 0.87-1.40) for rs8060157 and 1.01 (95 %CI 0.79-1.29) for rs10030044. There was no evidence to suggest that other SNPs in the surrounding regions of these SNPs might predict response to tamoxifen. Results from these two prevention trials do not support the earlier findings. rs8060157 in ZNF423 and rs10030044 near CTSO do not appear to predict response to tamoxifen.

Incremental cost effectiveness of proton pump inhibitors for the prevention of non-steroidal anti-inflammatory drug ulcers: a pharmacoeconomic analysis linked to a case-control study.

PubMed

Vonkeman, Harald E; Braakman-Jansen, Louise M A; Klok, Rogier M; Postma, Maarten J; Brouwers, Jacobus R B J; van de Laar, Mart A F J

2008-01-01

We estimated the cost effectiveness of concomitant proton pump inhibitors (PPIs) in relation to the occurrence of non-steroidal anti-inflammatory drug (NSAID) ulcer complications. This study was linked to a nested case-control study. Patients with NSAID ulcer complications were compared with matched controls. Only direct medical costs were reported. For the calculation of the incremental cost effectiveness ratio we extrapolated the data to 1,000 patients using concomitant PPIs and 1,000 patients not using PPIs for 1 year. Sensitivity analysis was performed by 'worst case' and 'best case' scenarios in which the 95% confidence interval (CI) of the odds ratio (OR) and the 95% CI of the cost estimate of a NSAID ulcer complication were varied. Costs of PPIs was varied separately. In all, 104 incident cases and 284 matched controls were identified from a cohort of 51,903 NSAID users with 10,402 NSAID exposition years. Use of PPIs was associated with an adjusted OR of 0.33 (95% CI 0.17 to 0.67; p = 0.002) for NSAID ulcer complications. In the extrapolation the estimated number of NSAID ulcer complications was 13.8 for non-PPI users and 3.6 for PPI users. The incremental total costs were euro 50,094 higher for concomitant PPIs use. The incremental cost effectiveness ratio was euro 4,907 per NSAID ulcer complication prevented when using the least costly PPIs. Concomitant use of PPIs for the prevention of NSAID ulcer complications costs euro 4,907 per NSAID ulcer complication prevented when using the least costly PPIs. The price of PPIs highly influenced the robustness of the results.

Risk of malignancy with systemic psoriasis treatment in the Psoriasis Longitudinal Assessment Registry.

PubMed

Fiorentino, David; Ho, Vincent; Lebwohl, Mark G; Leite, Luiz; Hopkins, Lori; Galindo, Claudia; Goyal, Kavitha; Langholff, Wayne; Fakharzadeh, Steven; Srivastava, Bhaskar; Langley, Richard G

2017-11-01

The effect of systemic therapy on malignancy risk among patients with psoriasis is not fully understood. Evaluate the impact of systemic treatment on malignancy risk among patients with psoriasis in the Psoriasis Longitudinal Assessment and Registry (PSOLAR). Nested case-control analyses were performed among patients with no history of malignancy. Cases were defined as first malignancy (other than nonmelanoma skin cancer) in the Psoriasis Longitudinal Assessment and Registry, and controls were matched by age, sex, geographic region, and time on registry. Study therapies included methotrexate, ustekinumab, and tumor necrosis factor-α (TNF-α) inhibitors. Exposure was defined as 1 or more doses of study therapy within 12 months of malignancy onset and further stratified by duration of therapy. Multivariate conditional logistic regression, adjusted for potential confounders, was used to estimate odds ratios of malignancies associated with therapy. Among 12,090 patients, 252 malignancy cases were identified and 1008 controls were matched. Treatment with methotrexate or ustekinumab for more than 0 months to less than 3 months, 3 months to less than 12 months, or 12 months or longer was not associated with increased malignancy risk versus no exposure. Longer-term (≥12 months) (odds ratio, 1.54; 95% confidence interval, 1.10-2.15; P = .01), but not shorter-term treatment, with a TNF-α inhibitor was associated with increased malignancy risk. Cases and controls could belong to 1 or more therapy categories. Long-term (≥12 months) treatment with a TNF-α inhibitor, but not methotrexate and ustekinumab, may increase risk for malignancy in patients with psoriasis. Copyright © 2017 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

Investigation of a cluster of pituitary adenomas in workers in the aluminum industry.

PubMed

Cullen, M R; Checkoway, H; Alexander, B H

1996-11-01

Four cases of pituitary adenoma among employees at a primary aluminum production factory were identified over a five year period by a community physician. The objective of this investigation was to determine whether there has been a comparable high incidence in other aluminum factories, and if particular jobs, departments, or activities in the industry are associated with higher rates of the disease. Pituitary adenoma in employees at all United States factories of the company for the years 1989-94 was assessed by a search of a health data information bank and an insurance data base covering present and past employees of the corporation. The incidence in the aluminum workers was estimated and compared with the workers in the index plant. A nested case control study was conducted to compare employment histories of identified cases with those of age and sex matched controls selected from the health information data base. 25 cases, including the index cases, were identified which had been diagnosed during the period 1989-94. The resulting rate of 10.4/100,000 person-years was much lower than that at the index plant. Case-control analysis showed no coherent pattern of location, department, or job significantly associated with risk. In particular, jobs and departments associated with exposures common to aluminum smelting-such as coal tar pitch volatiles and fluorides-were shown to be uncommon among cases compared with age and sex matched controls. Overall, despite the unprecedented cluster at a single plant, no strong evidence was found that the rate of pituitary adenoma is increased in aluminum workers generally. We found no association with any work activity or location in the industry to suggest a work related or exposure related cause for the disease.

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.

Protecting unknown two-qubit entangled states by nesting Uhrig's dynamical decoupling sequences

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

Mukhtar, Musawwadah; Soh, Wee Tee; Saw, Thuan Beng

2010-11-15

Future quantum technologies rely heavily on good protection of quantum entanglement against environment-induced decoherence. A recent study showed that an extension of Uhrig's dynamical decoupling (UDD) sequence can (in theory) lock an arbitrary but known two-qubit entangled state to the Nth order using a sequence of N control pulses [Mukhtar et al., Phys. Rev. A 81, 012331 (2010)]. By nesting three layers of explicitly constructed UDD sequences, here we first consider the protection of unknown two-qubit states as superposition of two known basis states, without making assumptions of the system-environment coupling. It is found that the obtained decoherence suppression canmore » be highly sensitive to the ordering of the three UDD layers and can be remarkably effective with the correct ordering. The detailed theoretical results are useful for general understanding of the nature of controlled quantum dynamics under nested UDD. As an extension of our three-layer UDD, it is finally pointed out that a completely unknown two-qubit state can be protected by nesting four layers of UDD sequences. This work indicates that when UDD is applicable (e.g., when the environment has a sharp frequency cutoff and when control pulses can be taken as instantaneous pulses), dynamical decoupling using nested UDD sequences is a powerful approach for entanglement protection.« less

Experimental shifts in egg-nest contrasts do not alter egg rejection responses in an avian host-brood parasite system.

PubMed

Hauber, Mark E; Aidala, Zachary; Igic, Branislav; Shawkey, Matthew D; Moskát, Csaba

2015-09-01

Obligate brood parasitic birds exploit their hosts to provide care for unrelated young in the nest. Potential hosts can reduce the cost of parasitism by rejecting foreign eggs from the nest. Observational, comparative, and experimental studies have concluded that most hosts use the coloration and patterning of eggshells to discriminate between own and foreign eggs in the nest. However, an alternative hypothesis is that birds use the colour contrasts between eggshells and the nest lining to identify parasitic eggs (egg-nest contrast hypothesis). In support of this hypothesis, we found that the avian perceivable chromatic contrasts between dyed eggs and unmanipulated nest linings significantly and negatively covaried with the rejection rates of different dyed eggs of the great reed warbler Acrocephalus arundinaceus, a frequently parasitized host of the common cuckoo Cuculus canorus. To experimentally test whether egg-nest contrasts influence rejection, we reciprocally dyed both eggs and the nest lining of this host species with one of two colours: orange and green. Contrary to the egg-nest contrast hypothesis, host rejection patterns in response to dyed eggs were not altered by dyeing nests, relative to unmanipulated control eggs and nests. In turn, experimental egg colour was the only significant predictor of egg rejection rate. Our results demonstrate that egg-nest contrast is a collateral, not a causal factor in egg rejection, and confirm the conclusions of previous studies that hosts can rely on the parasitic egg's appearance itself to recognize the foreign egg in the nest.

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.

Cavities shield birds from effects of artificial light at night on sleep.

PubMed

Raap, Thomas; Pinxten, Rianne; Eens, Marcel

2018-05-20

Light pollution is an ever increasing worldwide problem disrupting animal behavior. Artificial light at night (ALAN) has been shown to affect sleep in wild birds. Even cavity-nesting bird species may be affected when sleeping inside their cavity. Correlational studies suggest that light from outside the cavity/nest box, for example from street lights, may affect sleep. We used an experimental design to study to what extent nest boxes shield animals from effects of ALAN on sleep. We recorded individual sleep behavior of free-living great tits (Parus major) that were roosting in dark nest boxes and exposed their nest box entrance to ALAN the following night (1.6 lux white LED light; a similar light intensity as was found at nest boxes near street lights). Their behavior was compared to that of control birds sleeping in dark nest boxes on both nights. Our experimental treatment did not affect sleep behavior. Sleep behavior of birds in the control group did not differ from that of individuals in the light treated group. Our results suggest that during winter cavities shield birds from some effects of ALAN. Furthermore, given that effects of ALAN and exposure to artificial light are species-, sex-, and season-dependent, it is important that studies using wild animals quantify individual exposure to light pollution, and be cautious in the interpretation and generalization of the effects, or lack thereof, from light pollution. Rigorous studies are necessary to examine individual light exposure and its consequences in cavity- and open-nesting birds. © 2018 Wiley Periodicals, Inc.

Nest signature changes throughout colony cycle and after social parasite invasion in social wasps

PubMed Central

Blancato, Giuliano; Picchi, Laura; Lucas, Christophe

2017-01-01

Social insects recognize their nestmates by means of a cuticular hydrocarbon signature shared by colony members, but how nest signature changes across time has been rarely tested in longitudinal studies and in the field. In social wasps, the chemical signature is also deposited on the nest surface, where it is used by newly emerged wasps as a reference to learn their colony odor. Here, we investigate the temporal variations of the chemical signature that wasps have deposited on their nests. We followed the fate of the colonies of the social paper wasp Polistes biglumis in their natural environment from colony foundation to decline. Because some colonies were invaded by the social parasite Polistes atrimandibularis, we also tested the effects of social parasites on the nest signature. We observed that, as the season progresses, the nest signature changed; the overall abundance of hydrocarbons as well as the proportion of longer-chain and branched hydrocarbons increased. Where present, social parasites altered the host-nest signature qualitatively (adding parasite-specific alkenes) and quantitatively (by interfering with the increase in overall hydrocarbon abundance). Our results show that 1) colony odor is highly dynamic both in colonies controlled by legitimate foundresses and in those controlled by social parasites; 2) emerged offspring contribute little to colony signature, if at all, in comparison to foundresses; and 3) social parasites, that later mimic host signature, initially mark host nests with species-specific hydrocarbons. This study implies that important updating of the neural template used in nestmate recognition should occur in social insects. PMID:29261775

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

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.

Florida Harvester Ant Nest Architecture, Nest Relocation and Soil Carbon Dioxide Gradients

PubMed Central

Tschinkel, Walter R.

2013-01-01

Colonies of the Florida harvester ant, Pogonomyrmex badius, excavate species-typical subterranean nests up the 3 m deep with characteristic vertical distribution of chamber area/shape, spacing between levels and vertical arrangement of the ants by age and brood stage. Colonies excavate and occupy a new nest about once a year, and doing so requires that they have information about the depth below ground. Careful excavation and mapping of vacated and new nests revealed that there was no significant difference between the old and new nests in any measure of nest size, shape or arrangement. Colonies essentially built a replicate of the just-vacated nest (although details differed), and they did so in less than a week. The reason for nest relocation is not apparent. Tschinkel noted that the vertical distribution of chamber area, worker age and brood type was strongly correlated to the soil carbon dioxide gradient, and proposed that this gradient serves as a template for nest excavation and vertical distribution. To test this hypothesis, the carbon dioxide gradient of colonies that were just beginning to excavate a new nest was eliminated by boring 6 vent holes around the forming nest, allowing the soil CO2 to diffuse into the atmosphere and eliminating the gradient. Sadly, neither the nest architecture nor the vertical ant distribution of vented nests differed from either unvented control or from their own vacated nest. In a stronger test, workers excavated a new nest under a reversed carbon dioxide gradient (high concentration near the surface, low below). Even under these conditions, the new and old nests did not differ significantly, showing that the soil carbon dioxide gradient does not serve as a template for nest construction or vertical worker distribution. The possible importance of soil CO2 gradients for soil-dwelling animals is discussed. PMID:23555829

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.

Monolithically compatible impedance measurement

DOEpatents

Ericson, Milton Nance; Holcomb, David Eugene

2002-01-01

A monolithic sensor includes a reference channel and at least one sensing channel. Each sensing channel has an oscillator and a counter driven by the oscillator. The reference channel and the at least one sensing channel being formed integrally with a substrate and intimately nested with one another on the substrate. Thus, the oscillator and the counter have matched component values and temperature coefficients. A frequency determining component of the sensing oscillator is formed integrally with the substrate and has an impedance parameter which varies with an environmental parameter to be measured by the sensor. A gating control is responsive to an output signal generated by the reference channel, for terminating counting in the at least one sensing channel at an output count, whereby the output count is indicative of the environmental parameter, and successive ones of the output counts are indicative of changes in the environmental parameter.

What parental characteristics can predict child maltreatment at the Emergency Department? Considering expansion of the Hague Protocol.

PubMed

Diderich, Hester M; Dechesne, Mark; Fekkes, Minne; Verkerk, Paul H; Buitendijk, Simone E; Oudesluys-Murphy, Anne-Marie

2015-08-01

The Hague Protocol considers three parental characteristics of Emergency Department adult patients to identify child abuse: (a) domestic violence, (b) intoxication, and (c) suicide attempt or auto mutilation. This study investigated whether additional parental characteristics could be included to improve the chance of detection. Using a nested case-control design, we compared parents identified as child abusers who were missed by the Protocol with a matched group of nonabusing parents. The parental characteristics used were, among others, all physical injuries possibly resulting from domestic violence, psychological, or mental complaints that might indicate elevated domestic stress levels and the number of Emergency Department visits during the previous year. None of the characteristics were statistically significantly associated with child abuse. The Hague Protocol will not be improved by adding one or more of the characteristics that were investigated.

Female turtles from hot nests: is it duration of incubation or proportion of development at high temperatures that matters?

PubMed

Georges, Arthur

1989-11-01

Mean daily temperature in natural nests of freshwater turtles with temperature-dependent sex determination is known to be a poor predictor of hatchling sex ratios when nest temperatures fluctuate. To account for this, a model was developed on the assumption that females will emerge from eggs when more than half of embryonic development occurs above the threshold temperature for sex determination rather than from eggs that spend more than half their time above the threshold. The model is consistent with previously published data and in particular explains the phenomenon whereby the mean temperature that best distinguishes between male and female nests decreases with increasing variability in nest temperature. The model, if verified by controlled experiments, has important implications for our understanding of temperature-dependent sex determination in natural nests. Both mean nest temperature and "hours spent above the threshold" will be poor predictors of hatchling sex ratios. Studies designed to investigate latitudinal trends and inter-specific differences in the threshold temperature will need to consider latitudinal and inter-specific variation in the magnitude of diel fluctuations in nest temperature, and variation in factors influencing the magnitude of those fluctuations, such as nest depth. Furthermore, any factor that modifies the relationship between developmental rate and temperature can be expected to influence hatchling sex ratios in natural nests, especially when nest temperatures are close to the threshold.

Light pollution disrupts sleep in free-living animals

PubMed Central

Raap, Thomas; Pinxten, Rianne; Eens, Marcel

2015-01-01

Artificial lighting can alter individual behaviour, with often drastic and potentially negative effects on biological rhythms, daily activity and reproduction. Whether this is caused by a disruption of sleep, an important widespread behaviour enabling animals to recover from daily stress, is unclear. We tested the hypothesis that light pollution disrupts sleep by recording individual sleep behaviour of great tits, Parus major, that were roosting in dark nest-boxes and were exposed to light-emitting diode light the following night. Their behaviour was compared to that of control birds sleeping in dark nest-boxes on both nights. Artificial lighting caused experimental birds to wake up earlier, sleep less (–5%) and spent less time in the nest-box as they left their nest-box earlier in the morning. Experimental birds did not enter the nest-box or fall asleep later than controls. Although individuals in lit nest-boxes did not wake up more often nor decreased the length of their sleep bouts, females spent a greater proportion of the night awake. Our study provides the first direct proof that light pollution has a significant impact on sleep in free-living animals, in particular in the morning, and highlights a mechanism for potential effects of light pollution on fitness. PMID:26337732

Ectoparasitism and the role of green nesting material in the European starling

USGS Publications Warehouse

Fauth, P.T.; Krementz, D.G.; Hines, J.E.

1991-01-01

The use of green nesting material is wide-spread among birds. Recent evidence suggests that birds use secondary chemicals contained in green plants to control ectoparasites. We manipulated green nesting material and ectoparasites of European starlings (Sturnus vulgaris ) to test two hypotheses: (1) ectoparasites adversely affect prefledging survival and morphometrics or postfledging survival, and (2) green nesting material ameliorates the effects of ectoparasites. We recorded fat score, number of scabs, tarsal length, body mass, and hematocrit level on each nestling 17 days after hatching. We also fitted each nestling with unique patagial tags and resighted the starlings for 6-8 weeks after fledging to estimate survival and sighting rates. Nests devoid of green nesting material and dusted with the insecticide, carbaryl, had fewer high ectoparasite infestations, and nestlings had significantly lower scab scores, and significantly higher body masses than nestlings in undusted boxes. However, there was no difference in postfledging survival between birds from carbaryl-treated and undusted nests.

Daily survival rates for nests of Black Skimmers from a core breeding area of the Southeastern USA

USGS Publications Warehouse

Brooks, Gillian L.; Sanders, Felicia J.; Gerard, Patrick D.; Jodice, Patrick G.R.

2014-01-01

Little is known about the reproductive success of Black Skimmers (Rynchops niger) throughout the southeastern USA where availability of undisturbed beaches for nesting is limited. Daily survival rates (DSR) of nests were examined at three nesting sites in Cape Romain National Wildlife Refuge (CRNWR), South Carolina, USA, 2009–2010. The percent of successful nests (n  =  346 nests) ranged from 42–69% among colony sites when data were pooled across both years. The DSR of nests was primarily related to colony site, predation risk, height of high tide, and clutch size. Predation and overwash were the principal causes of identifiable nest loss, each accounting for ∼33% of nest failures during the two study years. Because of the challenges of resighting skimmer chicks, we were not able to measure chick survival effectively and therefore accurate measures of productivity remain elusive. High variability in nest success among sites within close proximity to each other (<20 km) suggests factors at local scales such as disturbance, predation, and overwash events strongly influenced nest success of Black Skimmers during these 2 years as opposed to more region-wide stressors such as tropical storms or food availability. Although time-intensive techniques to control predators do exist, management options to limit flooding and overwash are far more limited. Conservation of Black Skimmers in the southeastern USA would benefit from coordinated, multi-state efforts to measure nest and chick survival.

Controlling nested wrinkle morphology through the boundary effect on narrow-band thin films

NASA Astrophysics Data System (ADS)

Xu, Hanyang; Shi, Tielin; Liao, Guanglan; Xia, Qi

2017-07-01

We describe the formation of nested wrinkles created by the thermal mismatch between a narrow-band thin film and a compliant substrate. When a film is described as "narrow-band", it literally means that the film band width is much shorter than its length; more precisely, it means that the width is comparable with the wavelength of the wrinkles. A silicon mask was used during film sputtering to create narrow-band films on poly (dimethylsiloxane) substrate, thus creating regular boundaries to steer local stresses and control wrinkle morphology. Disordered nano-scale wrinkles were found nested within highly ordered micro-scale sinusoidal wrinkles. The formation of nested wrinkles was explained through the amplitude and wavelength saturation of nano-scale wrinkles. The disordered morphology of nano-scale wrinkles and the highly ordered morphology of micro-scale wrinkles were explained by using the boundary effect.

Acute kidney injury and edaravone in acute ischemic stroke: the Fukuoka Stroke Registry.

PubMed

Kamouchi, Masahiro; Sakai, Hironori; Kiyohara, Yutaka; Minematsu, Kazuo; Hayashi, Kunihiko; Kitazono, Takanari

2013-11-01

A free radical scavenger, edaravone, which has been used for the treatment of ischemic stroke, was reported to cause acute kidney injury (AKI) as a fatal adverse event. The aim of the present study was to clarify whether edaravone is associated with AKI in patients with acute ischemic stroke. From the Fukuoka Stroke Registry database, 5689 consecutive patients with acute ischemic stroke who were hospitalized within 24 hours of the onset of symptoms were included in this study. A logistic regression analysis for the Fukuoka Stroke Registry cohort was done to identify the predictors for AKI. A propensity score-matched nested case-control study was also performed to elucidate any association between AKI and edaravone. Acute kidney injury occurred in 128 of 5689 patients (2.2%) with acute ischemic stroke. A multivariate analysis revealed that the stroke subtype, the basal serum creatinine level, and the presence of infectious complications on admission were each predictors of developing AKI. In contrast, a free radical scavenger, edaravone, reduced the risk of developing AKI (multivariate-adjusted odds ratio [OR] .45, 95% confidence interval [CI] .30-.67). Propensity score-matched case-control study confirmed that edaravone use was negatively associated with AKI (propensity score-adjusted OR .46, 95% CI .29-.74). Although AKI has a significant impact on the clinical outcome of hospital inpatients, edaravone has a protective effect against the development of AKI in patients with acute ischemic stroke. Copyright © 2013 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Whip use and race progress are associated with horse falls in hurdle and steeplechase racing in the UK.

PubMed

Pinchbeck, G L; Clegg, P D; Proudman, C J; Morgan, K L; French, N R

2004-07-01

Falls during racing present a risk of injury to both horse and jockey and a risk of fatality to horses. To use video recordings of races to describe the circumstances surrounding horse falls at hurdle and steeplechase fences and to identify and quantify within-race risk factors for horse falls in National Hunt racing in the UK. A retrospective, matched, nested case-control study using video recordings of races was conducted on 6 UK racecourses. Cases and controls were matched on both race type and jump number at which the fall occurred. Conditional logistic regression analysis was used to examine the univariable and multivariable relationship between predictor variables and the risk of falling. The risk of falling was significantly associated with whip use and race progress. Horses which were being whipped and progressing through the race were at greater than 7 times the risk of falling compared to horses which were not being whipped and which had no change in position or lost position through the field. This study has identified whip use and the position of the horse with respect to others in the field as potential risk factors for horse falls. If these findings are confirmed by the use of intervention trials (e.g. with whip-free or restricted whip use races), modifications could be introduced which would reduce the frequency of horse falls, leading to improved equine welfare.

First trimester serum afamin concentrations are associated with the development of pre-eclampsia and gestational diabetes mellitus in pregnant women.

PubMed

Tramontana, Allessandra; Dieplinger, Benjamin; Stangl, Gerhard; Hafner, Erich; Dieplinger, Hans

2018-01-01

Aim of this study was to assess the prognostic capability of afamin to predict pregnancy complications. First-trimester screening was consecutively performed in 4948 pregnant women, of whom 474 women developed pregnancy complications [gestational hypertension (n=84), pre-eclampsia (n=30), intrauterine growth restriction (n=107), preterm birth (n=44), and gestational diabetes mellitus (n=209)]. To each woman with pregnancy complications an uncomplicated pregnancy was matched for body mass index. Afamin serum concentrations were measured in 948 pregnant women at the first-trimester screening. Median afamin concentrations were significantly higher in women developing pre-eclampsia or gestational diabetes mellitus when compared to women with uncomplicated pregnancies (76mg/L vs. 65mg/L, p=0.001 and 80mg/L vs. 69mg/L, p<0.001). There was no difference in median afamin values between all other pregnancy complications and their matched controls. Increased afamin (i.e. >65mg/L) was a strong and independent predictor for the development of pre-eclampsia (risk ratio, 24.58; 95%CI, 2.82-214.12; p=0.004) as well as gestational diabetes mellitus (risk ratio, 2.07; 95%CI, 1.33-3.22; p=0.001). In this large nested case-control study increased afamin concentrations were a strong and independent predictor for pre-eclampsia and gestational diabetes mellitus, suggesting a potential role of afamin as predictive marker for pregnancy-related metabolic disorders. Copyright © 2017. Published by Elsevier B.V.

How to escape from the host nest: imperfect chemical mimicry in eucharitid parasitoids and exploitation of the ants' hygienic behavior.

PubMed

Pérez-Lachaud, Gabriela; Bartolo-Reyes, Juan Carlos; Quiroa-Montalván, Claudia M; Cruz-López, Leopoldo; Lenoir, Alain; Lachaud, Jean-Paul

2015-04-01

Communication in ants is based to a great extent on chemical compounds. Recognition of intruders is primarily based on cuticular hydrocarbon (CHC) profile matching but is prone to being cheated. Eucharitid wasps are specific parasitoids of the brood of ants; the immature stages are either well integrated within the colony or are protected within the host cocoons, whereas adult wasps at emergence must leave their host nest to reproduce and need to circumvent the ant recognition system to escape unscathed. The behavioral interactions between eucharitid wasps and workers of their host, the Neotropical ant Ectatomma tuberculatum, are characterized. In experimental bioassays, newly emerged parasitoids were not violently aggressed. They remained still and were grabbed by ants upon contact and transported outside the nest; host workers were even observed struggling to reject them. Parasitoids were removed from the nest within five minutes, and most were unharmed, although two wasps (out of 30) were killed during the interaction with the ants. We analyzed the CHCs of the ant and its two parasitoids, Dilocantha lachaudii and Isomerala coronata, and found that although wasps shared all of their compounds with the ants, each wasp species had typical blends and hydrocarbon abundance was also species specific. Furthermore, the wasps had relatively few CHCs compared to E. tuberculatum (22-44% of the host components), and these were present in low amounts. Wasps, only partially mimicking the host CHC profile, were immediately recognized as alien and actively removed from the nest by the ants. Hexane-washed wasps were also transported to the refuse piles, but only after being thoroughly inspected and after most of the workers had initially ignored them. Being recognized as intruder may be to the parasitoids' advantage, allowing them to quickly leave the natal nest, and therefore enhancing the fitness of these very short lived parasitoids. We suggest that eucharitids take advantage of the hygienic behavior of ants to quickly escape from their host nests. Copyright © 2015 Elsevier Ltd. All rights reserved.

Dinosaur origin of egg color: oviraptors laid blue-green eggs

PubMed Central

Yang, Tzu-Ruei; Sander, Philipp N.; Schneider, Marion; Engeser, Marianne; Kath-Schorr, Stephanie; Müller, Christa E.; Sander, P. Martin

2017-01-01

Protoporphyrin (PP) and biliverdin (BV) give rise to the enormous diversity in avian egg coloration. Egg color serves several ecological purposes, including post-mating signaling and camouflage. Egg camouflage represents a major character of open-nesting birds which accomplish protection of their unhatched offspring against visually oriented predators by cryptic egg coloration. Cryptic coloration evolved to match the predominant shades of color found in the nesting environment. Such a selection pressure for the evolution of colored or cryptic eggs should be present in all open nesting birds and relatives. Many birds are open-nesting, but protect their eggs by continuous brooding, and thus exhibit no or minimal eggshell pigmentation. Their closest extant relatives, crocodiles, protect their eggs by burial and have unpigmented eggs. This phylogenetic pattern led to the assumption that colored eggs evolved within crown birds. The mosaic evolution of supposedly avian traits in non-avian theropod dinosaurs, however, such as the supposed evolution of partially open nesting behavior in oviraptorids, argues against this long-established theory. Using a double-checking liquid chromatography ESI-Q-TOF mass spectrometry routine, we traced the origin of colored eggs to their non-avian dinosaur ancestors by providing the first record of the avian eggshell pigments protoporphyrin and biliverdin in the eggshells of Late Cretaceous oviraptorid dinosaurs. The eggshell parataxon Macroolithus yaotunensis can be assigned to the oviraptor Heyuannia huangi based on exceptionally preserved, late developmental stage embryo remains. The analyzed eggshells are from three Late Cretaceous fluvial deposits ranging from eastern to southernmost China. Reevaluation of these taphonomic settings, and a consideration of patterns in the porosity of completely preserved eggs support an at least partially open nesting behavior for oviraptorosaurs. Such a nest arrangement corresponds with our reconstruction of blue-green eggs for oviraptors. According to the sexual signaling hypothesis, the reconstructed blue-green eggs support the origin of previously hypothesized avian paternal care in oviraptorid dinosaurs. Preserved dinosaur egg color not only pushes the current limits of the vertebrate molecular and associated soft tissue fossil record, but also provides a perspective on the potential application of this unexplored paleontological resource. PMID:28875070

Dinosaur origin of egg color: oviraptors laid blue-green eggs.

PubMed

Wiemann, Jasmina; Yang, Tzu-Ruei; Sander, Philipp N; Schneider, Marion; Engeser, Marianne; Kath-Schorr, Stephanie; Müller, Christa E; Sander, P Martin

2017-01-01

Protoporphyrin (PP) and biliverdin (BV) give rise to the enormous diversity in avian egg coloration. Egg color serves several ecological purposes, including post-mating signaling and camouflage. Egg camouflage represents a major character of open-nesting birds which accomplish protection of their unhatched offspring against visually oriented predators by cryptic egg coloration. Cryptic coloration evolved to match the predominant shades of color found in the nesting environment. Such a selection pressure for the evolution of colored or cryptic eggs should be present in all open nesting birds and relatives. Many birds are open-nesting, but protect their eggs by continuous brooding, and thus exhibit no or minimal eggshell pigmentation. Their closest extant relatives, crocodiles, protect their eggs by burial and have unpigmented eggs. This phylogenetic pattern led to the assumption that colored eggs evolved within crown birds. The mosaic evolution of supposedly avian traits in non-avian theropod dinosaurs, however, such as the supposed evolution of partially open nesting behavior in oviraptorids, argues against this long-established theory. Using a double-checking liquid chromatography ESI-Q-TOF mass spectrometry routine, we traced the origin of colored eggs to their non-avian dinosaur ancestors by providing the first record of the avian eggshell pigments protoporphyrin and biliverdin in the eggshells of Late Cretaceous oviraptorid dinosaurs. The eggshell parataxon Macroolithus yaotunensis can be assigned to the oviraptor Heyuannia huangi based on exceptionally preserved, late developmental stage embryo remains. The analyzed eggshells are from three Late Cretaceous fluvial deposits ranging from eastern to southernmost China. Reevaluation of these taphonomic settings, and a consideration of patterns in the porosity of completely preserved eggs support an at least partially open nesting behavior for oviraptorosaurs. Such a nest arrangement corresponds with our reconstruction of blue-green eggs for oviraptors. According to the sexual signaling hypothesis, the reconstructed blue-green eggs support the origin of previously hypothesized avian paternal care in oviraptorid dinosaurs. Preserved dinosaur egg color not only pushes the current limits of the vertebrate molecular and associated soft tissue fossil record, but also provides a perspective on the potential application of this unexplored paleontological resource.

Human Exposure to Endocrine-Disrupting Chemicals and Prenatal Risk Factors for Cryptorchidism and Hypospadias: A Nested Case–Control Study

PubMed Central

Fernandez, Mariana F.; Olmos, Begoña; Granada, Alicia; López-Espinosa, Maria José; Molina-Molina, José-Manuel; Fernandez, Juan Manuel; Cruz, Milagros; Olea-Serrano, Fátima; Olea, Nicolás

2007-01-01

Background Exposure to xenoestrogens during pregnancy may disturb the development and function of male sexual organs. Objective In this study we aimed to determine whether the combined effect of environmental estrogens measured as total effective xenoestrogen burden (TEXB) is a risk factor for male urogenital malformations. Methods In a case–control study, nested in a mother–child cohort (n = 702) established at Granada University Hospital, we compared 50 newborns with diagnosis of cryptorchidism and/or hypospadias with 114 boys without malformations matched by gestational age, date of birth, and parity. Controls did not differ from the total cohort in confounding variables. TEXB and levels of 16 organochlorine pesticides were measured in placenta tissues. Characteristics of parents, pregnancy, and birth were gathered by questionnaire. We used conditional and unconditional regression models to estimate odds ratios (ORs) and 95% confidence intervals (CIs). Results TEXB from organohalogenated compounds was detectable in 72% and 54% of case and control placentas, respectively. Compared with controls, cases had an OR for detectable versus non-detectable TEXB of 2.82 (95% CI, 1.10–7.24). More pesticides were detected in cases than in controls (9.34 ± 3.19 vs. 6.97 ± 3.93). ORs for cases with detectable levels of pesticides, after adjusting for potential confounders in the conditional regression analysis, were o,p′-DDT (OR = 2.25; 95% CI, 1.03–4.89), p,p′-DDT (OR = 2.63; 95% CI, 1.21–5.72), lindane (OR = 3.38; 95% CI, 1.36–8.38), mirex (OR = 2.85; 95% CI, 1.22–6.66), and endosulfan alpha (OR = 2.19; 95% CI, 0.99–4.82). Engagement of mothers in agriculture (OR = 3.47; 95% CI, 1.33–9.03), fathers’ occupational exposure to xenoestrogens (OR = 2.98; 95% CI, 1.11–8.01), and history of previous stillbirths (OR = 4.20; 95% CI, 1.11–16.66) were also associated with risk of malformations. Conclusions We found an increased risk for male urogenital malformations related to the combined effect of environmental estrogens in placenta. PMID:18174944

Breeding sex ratios in adult leatherback turtles (Dermochelys coriacea) may compensate for female-biased hatchling sex ratios.

PubMed

Stewart, Kelly R; Dutton, Peter H

2014-01-01

For vertebrates with temperature-dependent sex determination, primary (or hatchling) sex ratios are often skewed, an issue of particular relevance to concerns over effects of climate change on populations. However, the ratio of breeding males to females, or the operational sex ratio (OSR), is important to understand because it has consequences for population demographics and determines the capacity of a species to persist. The OSR also affects mating behaviors and mate choice, depending on the more abundant sex. For sea turtles, hatchling and juvenile sex ratios are generally female-biased, and with warming nesting beach temperatures, there is concern that populations may become feminized. Our purpose was to evaluate the breeding sex ratio for leatherback turtles at a nesting beach in St. Croix, USVI. In 2010, we sampled nesting females and later sampled their hatchlings as they emerged from nests. Total genomic DNA was extracted and all individuals were genotyped using 6 polymorphic microsatellite markers. We genotyped 662 hatchlings from 58 females, matching 55 females conclusively to their nests. Of the 55, 42 females mated with one male each, 9 mated with 2 males each and 4 mated with at least 3 males each, for a multiple paternity rate of 23.6%. Using GERUD1.0, we reconstructed parental genotypes, identifying 47 different males and 46 females for an estimated breeding sex ratio of 1.02 males for every female. Thus we demonstrate that there are as many actively breeding males as females in this population. Concerns about female-biased adult sex ratios may be premature, and mate choice or competition may play more of a role in sea turtle reproduction than previously thought. We recommend monitoring breeding sex ratios in the future to allow the integration of this demographic parameter in population models.

The perfect family: decision making in biparental care.

PubMed

Akçay, Erol; Roughgarden, Joan

2009-10-13

Previous theoretical work on parental decisions in biparental care has emphasized the role of the conflict between evolutionary interests of parents in these decisions. A prominent prediction from this work is that parents should compensate for decreases in each other's effort, but only partially so. However, experimental tests that manipulate parents and measure their responses fail to confirm this prediction. At the same time, the process of parental decision making has remained unexplored theoretically. We develop a model to address the discrepancy between experiments and the theoretical prediction, and explore how assuming different decision making processes changes the prediction from the theory. We assume that parents make decisions in behavioral time. They have a fixed time budget, and allocate it between two parental tasks: provisioning the offspring and defending the nest. The proximate determinant of the allocation decisions are parents' behavioral objectives. We assume both parents aim to maximize the offspring production from the nest. Experimental manipulations change the shape of the nest production function. We consider two different scenarios for how parents make decisions: one where parents communicate with each other and act together (the perfect family), and one where they do not communicate, and act independently (the almost perfect family). The perfect family model is able to generate all the types of responses seen in experimental studies. The kind of response predicted depends on the nest production function, i.e. how parents' allocations affect offspring production, and the type of experimental manipulation. In particular, we find that complementarity of parents' allocations promotes matching responses. In contrast, the relative responses do not depend on the type of manipulation in the almost perfect family model. These results highlight the importance of the interaction between nest production function and how parents make decisions, factors that have largely been overlooked in previous models.

Autism Spectrum Disorder and Particulate Matter Air Pollution before, during, and after Pregnancy: A Nested Case–Control Analysis within the Nurses’ Health Study II Cohort

PubMed Central

Roberts, Andrea L.; Lyall, Kristen; Hart, Jaime E.; Just, Allan C.; Laden, Francine; Weisskopf, Marc G.

2014-01-01

Background Autism spectrum disorder (ASD) is a developmental disorder with increasing prevalence worldwide, yet has unclear etiology. Objective We explored the association between maternal exposure to particulate matter (PM) air pollution and odds of ASD in her child. Methods We conducted a nested case–control study of participants in the Nurses’ Health Study II (NHS II), a prospective cohort of 116,430 U.S. female nurses recruited in 1989, followed by biennial mailed questionnaires. Subjects were NHS II participants’ children born 1990–2002 with ASD (n = 245), and children without ASD (n = 1,522) randomly selected using frequency matching for birth years. Diagnosis of ASD was based on maternal report, which was validated against the Autism Diagnostic Interview-Revised in a subset. Monthly averages of PM with diameters ≤ 2.5 μm (PM2.5) and 2.5–10 μm (PM10–2.5) were predicted from a spatiotemporal model for the continental United States and linked to residential addresses. Results PM2.5 exposure during pregnancy was associated with increased odds of ASD, with an adjusted odds ratio (OR) for ASD per interquartile range (IQR) higher PM2.5 (4.42 μg/m3) of 1.57 (95% CI: 1.22, 2.03) among women with the same address before and after pregnancy (160 cases, 986 controls). Associations with PM2.5 exposure 9 months before or after the pregnancy were weaker in independent models and null when all three time periods were included, whereas the association with the 9 months of pregnancy remained (OR = 1.63; 95% CI: 1.08, 2.47). The association between ASD and PM2.5 was stronger for exposure during the third trimester (OR = 1.42 per IQR increase in PM2.5; 95% CI: 1.09, 1.86) than during the first two trimesters (ORs = 1.06 and 1.00) when mutually adjusted. There was little association between PM10–2.5 and ASD. Conclusions Higher maternal exposure to PM2.5 during pregnancy, particularly the third trimester, was associated with greater odds of a child having ASD. Citation Raz R, Roberts AL, Lyall K, Hart JE, Just AC, Laden F, Weisskopf MG. 2015. Autism spectrum disorder and particulate matter air pollution before, during, and after pregnancy: a nested case–control analysis within the Nurses’ Health Study II cohort. Environ Health Perspect 123:264–270; http://dx.doi.org/10.1289/ehp.1408133 PMID:25522338

Cryptic cuckoo eggs hide from competing cuckoos

PubMed Central

Gloag, Ros; Keller, Laurie-Anne; Langmore, Naomi E.

2014-01-01

Interspecific arms races between cuckoos and their hosts have produced remarkable examples of mimicry, with parasite eggs evolving to match host egg appearance and so evade removal by hosts. Certain bronze-cuckoo species, however, lay eggs that are cryptic rather than mimetic. These eggs are coated in a low luminance pigment that camouflages them within the dark interiors of hosts' nests. We investigated whether cuckoo egg crypsis is likely to have arisen from the same coevolutionary processes known to favour egg mimicry. We added high and low luminance-painted eggs to the nests of large-billed gerygones (Gerygone magnirostris), a host of the little bronze-cuckoo (Chalcites minutillus). Gerygones rarely rejected either egg type, and did not reject natural cuckoo eggs. Cuckoos, by contrast, regularly removed an egg from clutches before laying their own and were five times more likely to remove a high luminance model than its low luminance counterpart. Given that we found one-third of all parasitized nests were exploited by multiple cuckoos, our results suggest that competition between cuckoos has been the key selective agent for egg crypsis. In such intraspecific arms races, crypsis may be favoured over mimicry because it can reduce the risk of egg removal to levels below chance. PMID:25122227

Chemical disguise as particular caste of host ants in the ant inquiline parasite Niphanda fusca (Lepidoptera: Lycaenidae)

PubMed Central

Hojo, Masaru K.; Wada-Katsumata, Ayako; Akino, Toshiharu; Yamaguchi, Susumu; Ozaki, Mamiko; Yamaoka, Ryohei

2008-01-01

The exploitation of parental care is common in avian and insect ‘cuckoos’ and these species engage in a coevolutionary arms race. Caterpillars of the lycaenid butterfly Niphanda fusca develop as parasites inside the nests of host ants (Camponotus japonicus) where they grow by feeding on the worker trophallaxis. We hypothesized that N. fusca caterpillars chemically mimic host larvae, or some particular castes of the host ant, so that the caterpillars are accepted and cared for by the host workers. Behaviourally, it was observed that the host workers enthusiastically tended glass dummies coated with the cuticular chemicals of larvae or males and those of N. fusca caterpillars living together. Cuticular chemical analyses revealed that N. fusca caterpillars grown in a host ant nest acquired a colony-specific blend of cuticular hydrocarbons (CHCs). Furthermore, the CHC profiles of the N. fusca caterpillars were particularly close to those of the males rather than those of the host larvae and the others. We suggest that N. fusca caterpillars exploit worker care by matching their cuticular profile to that of the host males, since the males are fed by trophallaxis with workers in their natal nests for approximately ten months. PMID:18842547

A new view of avian life-history evolution tested on an incubation paradox.

PubMed

Martin, Thomas E

2002-02-07

Viewing life-history evolution in birds based on an age-specific mortality framework can explain broad life-history patterns, including the long incubation periods in southern latitudes documented here. I show that incubation periods of species that are matched phylogenetically and ecologically between Argentina and Arizona are longer in Argentina. Long incubation periods have mystified scientists because they increase the accumulated risk of time-dependent mortality to young without providing a clear benefit. I hypothesize that parents of species with low adult mortality accept increased risk of mortality to their young from longer incubation if this allows reduced risk of mortality to themselves. During incubation, songbird parents can reduce risk of mortality to themselves by reducing nest attentiveness (percentage of time on the nest). Here I show that parents of species with lower adult mortality exhibit reduced nest attentiveness and that lower attentiveness is associated with longer incubation periods. However, the incubation period is also modified by juvenile mortality. Clutch size variation is also strongly correlated with age-specific mortality. Ultimately, adult and juvenile mortality explain variation in incubation and other life-history traits better than the historical paradigm.

First evidence of gregarious denning in opossums (Didelphimorphia, Didelphidae), with notes on their social behaviour

PubMed Central

Astúa, Diego; Carvalho, Rafael A.; Maia, Paula F.; Magalhães, Arthur R.; Loretto, Diogo

2015-01-01

The Didelphidae are considered solitary opossums with few social interactions, usually limited to mating-related or mother–pouch young interactions. Anecdotal reports suggest that additional interactions occur, including den sharing by a few individuals, usually siblings. Here, we report novel observations that indicate opossums are more social than previously thought. These include nest sharing by males and females of Marmosa paraguayana, Gracilinanus microtarsus and Marmosops incanus prior to the onset of the breeding season and without signs of sexual activity; this is taken to indicate early pair-bonding matching and cooperative nest building. We also recorded den sharing among recently weaned siblings of Didelphis aurita and Caluromys philander. In addition, we observed 13 individuals of Didelphis albiventris representing three age classes resting without agonistic interactions in a communal den. These are the first reports of gregarious behaviour involving so many individuals, which are either unrelated or represent siblings from at least two litters, already weaned, sharing the same den with three adults. Sociality in opossums is probably more complex than previously established, and field experimental designs combining the use of artificial nests with camera traps or telemetry may help to gauge the frequency and extent of these phenomena. PMID:26085500

Nutritional adequacy of a cows' milk exclusion diet in infancy.

PubMed

Maslin, Kate; Oliver, Erin M; Scally, Karen S; Atkinson, Josh; Foote, Keith; Venter, Carina; Roberts, Graham; Grimshaw, Kate E C

2016-01-01

Infants with suspected cows' milk allergy are required to follow a strict milk exclusion diet which may lead to nutritional deficiencies, especially if not supervised by a healthcare professional. The aim of this study was to assess the nutritional adequacy of a cows' milk exclusion diet in a group of UK infants over a period of 6 months. Participants in this study are a subgroup of the Prevalence of Infant Food Allergy study, a prospective food allergy birth cohort study from the South of England. Each infant consuming a milk free diet, following advice from a specialist allergy dietitian, was matched to two control infants who were consuming an unrestricted diet, forming a nested matched case-control study. Detailed food diaries completed prospectively for 1 week per month over a 5 month period, were coded and analysed according to a standard protocol. The diets of 39 infants (13 milk-free and 26 controls) were assessed. Mean age at diet commencement was 14 weeks. Two of the eleven infants started on an extensively hydrolysed formula did not tolerate it and required an amino acid formula for symptom resolution. All infants had mean intakes in excess of the estimated average requirement for energy and the recommended nutrient intake (RNI) for protein, calcium, iron, selenium, zinc, vitamins A, C and E. Vitamin D intake was in excess of the RNI at all time-points, except at 44 weeks of age. Across the study period, selenium intake was higher for infants consuming a milk free diet whilst vitamin C intake was higher for infants consuming an unrestricted diet. Differences were found between the two groups for protein, calcium, iron and vitamin E intakes at differing time points. This study demonstrated that although infants consuming a milk-free diet have a nutritional intake that is significantly different to matched controls who are eating an unrestricted diet, this difference is not constant and it is not seen for all nutrients. Further research in infants without dietetic input is needed to explore the nutritional implications of unsupervised cows' milk exclusion diets.

Increased urine semaphorin-3A is associated with renal damage in hypertensive patients with chronic kidney disease: a nested case-control study.

PubMed

Viazzi, Francesca; Ramesh, Ganesan; Jayakumar, Calpurnia; Leoncini, Giovanna; Garneri, Debora; Pontremoli, Roberto

2015-06-01

Semaphorins are guidance proteins implicated in several processes such as angiogenesis, organogenesis, cell migration, and cytokine release. Experimental studies showed that semaphorin-3a (SEMA3A) administration induces transient massive proteinuria, podocyte foot process effacement and endothelial cell damage in healthy animals. While SEMA3A signaling has been demonstrated to be mechanistically involved in experimental diabetic glomerulopathy and in acute kidney injury, to date its role in human chronic kidney disease (CKD) has not been investigated. To test the hypothesis that SEMA3A may play a role in human CKD, we performed a cross-sectional, nested, case-control study on 151 matched hypertensive patients with and without CKD. SEMA3A was quantified in the urine (USEMA) by ELISA. Glomerular filtration rate was estimated (eGFR) by the CKD-EPI formula and albuminuria was measured as albumin-to-creatinine ratio (ACR). USEMA levels were positively correlated with urine ACR (p = 0.001) and serum creatinine (p < 0.001). USEMA was higher in patients with both components of renal damage as compared to those with only one and those with normal renal function (p < 0.007 and <0.001, respectively). The presence of increased USEMA levels (i.e. top quartile) entailed a fourfold higher risk of combined renal damage (p < 0.001) and an almost twofold higher risk of macroalbuminuria (p = 0.005) or of reduced eGFR, even adjusting for confounding factors (p = 0.002). USEMA is independently associated with CKD in both diabetic and non diabetic hypertensive patients. Further studies may help clarify the mechanisms underlying this association and possibly the pathogenic changes leading to the development of CKD.

Welfare indicators in laying hens in relation to nest exclusion.

PubMed

Alm, M; Tauson, R; Holm, L; Wichman, A; Kalliokoski, O; Wall, H

2016-06-01

Consumer concerns about the welfare of laying hens are increasing, leading to increased interest in identifying reliable ways to assess welfare. The present study evaluated invasive and non-invasive welfare indicators in relation to a stressful challenge. The study included 126 Lohmann Selected Leghorn hens housed in furnished cages. Welfare indicators were measured between 61 and 70 wk of age in birds excluded from their nests for 5 consecutive d and control birds that had continuous access to nests. Baseline recordings were carried out in both groups prior to and post exclusion period. The assessed indicators were: corticosterone metabolites in droppings (FCM), corticosterone concentration in yolk, corticosterone concentration in plasma, irregularities of eggshells, heterophil to lymphocyte (H:L) ratio, tonic immobility duration, and feather cover. Behavioral observations showed that the birds had a clear preference for using the secluded nest sites, confirming that they were likely to perceive nest exclusion as an undesirable experience. Further, elevated levels of FCM in droppings, yolk corticosterone concentrations, H:L ratios and irregular eggshells were detected in both nest deprived and control birds during the exclusion. This suggests that these indicators were able to detect an increased stress response arising from nest deprivation, and it is hypothesized that the stress spread to birds in adjacent cages with access to nests. There was a positive and consistent correlation between FCM in droppings and eggshell irregularities, also supporting the use of eggshell irregularities as a potential non-invasive welfare indicator. However, the pattern of the stress response varied between indicators and correlations were generally few and inconsistent, highlighting the complexity of the relationship among welfare indicators. © 2016 Poultry Science Association Inc.

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

Exposure to levonorgestrel increases nest acquisition success and decreases sperm motility in the male fathead minnow (Pimephales promelas).

PubMed

Frankel, Tyler; Yonkos, Lance; Ampy, Franklin; Frankel, Jack

2018-04-01

Progestins are utilized as a component of human contraceptives, and commonly enter the environment via wastewater treatment plant effluent. Certain progestins activate fish androgen receptors and cause decreases in fecundity and masculinization of females. We used a nest acquisition assay and computer-assisted sperm analysis to examine the effects of levonorgestrel on male fathead minnow (Pimephales promelas) reproductive fitness. Males were exposed to 0, 10, or 100 ng/L levonorgestrel for 14 d. Combinations of a control male and a male from one of the treatments were placed into a competitive nesting assay, and the time each male spent holding the nest and time spent exhibiting aggressive behaviors were analyzed at 48 h postexposure. Semen samples were analyzed for total motility, straight-line velocity, curvilinear velocity, average path velocity, linearity, beat cross frequency, and wobble at 0, 30, 60, 90, and 120 s postactivation. Males exposed to either 10 or 100 ng/L of levonorgestrel exhibited increased nest acquisition success and lower levels of aggression compared with control-control pairings, as well as decreases in multiple sperm motion characteristics. Our results suggest that further research is required to ascertain the effects of levonorgestrel on male gamete quality and reproductive behaviors. Environ Toxicol Chem 2018;37:1131-1137. © 2017 SETAC. © 2017 SETAC.

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

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.

New use of low-dose aspirin and risk of colorectal cancer by stage at diagnosis: a nested case-control study in UK general practice.

PubMed

García Rodríguez, Luis A; Soriano-Gabarró, Montse; Bromley, Susan; Lanas, Angel; Cea Soriano, Lucía

2017-09-07

Evidence from clinical trial populations suggests low-dose aspirin reduces the risk of colorectal cancer (CRC). Part of this reduction in risk might be due to protection against metastatic disease. We investigated the risk of CRC among new-users of low-dose aspirin (75-300 mg), including risk by stage at diagnosis. Using The Health Improvement Network, we conducted a cohort study with nested case-control analysis. Two cohorts (N = 170,336 each) aged 40-89 years from 2000 to 2009 and free of cancer were identified: i) new-users of low-dose aspirin, ii) non-users of low-dose aspirin, at start of follow-up, matched by age, sex and previous primary care practitioner visits. Patients were followed for up to 12 years to identify incident CRC. 10,000 frequency-matched controls were selected by incidence density sampling where the odds ratio is an unbiased estimator of the incidence rate ratio (RR). RRs with 95% confidence intervals were calculated. Low-dose aspirin use was classified 'as-treated' independent from baseline exposure status to account for changes in exposure during follow-up. Current users of low-dose aspirin (use on the index date or in the previous 90 days) had a significantly reduced risk of CRC, RR 0.66 (95% CI 0.60-0.74). The reduction in risk was apparent across all age groups, and was unrelated to dose, indication, gender, CRC location or case-fatality status. Reduced risks occurred throughout treatment duration and with all low-dose aspirin doses. RRs by aspirin indication were 0.71 (0·63-0·79) and 0.60 (0.53-0.68) for primary and secondary cardiovascular protection, respectively. Among cases with staging information (n = 1421), RRs for current use of low-dose aspirin were 0.94 (0.66-1.33) for Dukes Stage A CRC, 0.54 (0.42-0.68) for Dukes B, 0.71 (0.56-0.91) for Dukes C, and 0.60 (0.48-0.74) for Dukes D. After 5 years' therapy, the RR for Dukes Stage A CRC was 0.53 (0.24-1.19). Patients starting low-dose aspirin therapy have a reduced risk of Stages B-D CRC, suggesting a role for low-dose aspirin in the progression of established CRC; a substantial reduction in the risk of Dukes A CRC may occur after 5 years' therapy.

Animal product consumption and subsequent fatal breast cancer risk among Seventh-day Adventists.

PubMed

Mills, P K; Annegers, J F; Phillips, R L

1988-03-01

Seventh-day Adventist women experience lower mortality rates from breast cancer than other white females in the United States. To evaluate the role of diet in relation to breast cancer within this unique population (more than one-half of all Adventist women are lacto-ovo-vegetarians), a nested case-control study was conducted including 142 cases of fatal breast cancer and 852 matched controls among California Seventh-day Adventist women in 1960-1980. No significant relations between the consumption of animal products (meat, milk, cheese, and eggs) and breast cancer were evident. Odds ratios of 1.00, 1.22, and 1.03 were observed for meat consumption categories of none or occasional, 1-3 days/week, and 4+ days/week, respectively. However, among those women who experienced a relatively early age at natural menopause (less than or equal to 48 years), a suggestive though nonsignificant, positive association between meat consumption and risk was noted. These relations remained unchanged after simultaneously controlling for the effects of other covariates (menstrual characteristics and obesity) via conditional logistic regression analysis. Risk was not related to age at first exposure to the vegetarian lifestyle nor to duration of exposure to the vegetarian lifestyle.

Mercury alters initiation and construction of nests by zebra finches, but not incubation or provisioning behaviors.

PubMed

Chin, Stephanie Y; Hopkins, William A; Cristol, Daniel A

2017-11-01

Mercury is an environmental contaminant that impairs avian reproduction, but the behavioral and physiological mechanisms underlying this effect are poorly understood. The objective of this study was to determine whether lifetime dietary exposure to mercury (1.2 µg/g wet weight in food) impacted avian parental behaviors, and how this might influence reproductive success. To distinguish between the direct effects of mercury on parents and offspring, we created four treatment groups of captive-bred zebra finches (Taeniopygia guttata), with control and mercury-exposed adults raising cross-fostered control or mercury-exposed eggs (from maternal transfer). Control parents were 23% more likely to fledge young than parents exposed to mercury, regardless of egg exposure. Mercury-exposed parents were less likely to initiate nests than controls and spent less time constructing them. Nests of mercury-exposed pairs were lighter, possibly due to an impaired ability to bring nest material into the nestbox. However, nest temperature, incubation behavior, and provisioning rate did not differ between parental treatments. Unexposed control eggs tended to have shorter incubation periods and higher hatching success than mercury-exposed eggs, but there was no effect of parental exposure on these parameters. We accidentally discovered that parent finches transfer some of their body burden of mercury to nestlings during feeding through secretion in the crop. These results suggest that, in mercury-exposed songbirds, pre-laying parental behaviors, combined with direct exposure of embryos to mercury, likely contribute to reduced reproductive success and should be considered in future studies. Further research is warranted in field settings, where parents are exposed to greater environmental challenges and subtle behavioral differences might have more serious consequences than were observed in captivity.

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

Serological Documentation of Maternal Influenza Exposure and Bipolar Disorder in Adult Offspring

PubMed Central

Canetta, Sarah E.; Bao, Yuanyuan; Co, Mary Dawn T.; Ennis, Francis A.; Cruz, John; Terajima, Masanori; Shen, Ling; Kellendonk, Christoph; Schaefer, Catherine A.; Brown, Alan S.

2014-01-01

Objective The goal of the present study was to evaluate whether serologically confirmed maternal exposure to influenza is associated with an increased risk of bipolar disorder in the offspring and with subtypes of bipolar disorder, with and without psychotic features. Method The study utilized a nested case-control design in the Child Health and Development Study birth cohort. Eighty-five cases of bipolar disorder were identified following extensive ascertainment and diagnostic assessment and matched to 170 controls in the analysis. Serological documentation of maternal exposure to influenza was determined using the hemagglutination inhibition assay. Results There was no association between serologically documented maternal exposure to influenza and bipolar disorder in offspring. However, maternal serologic influenza exposure was related to a significant, fivefold increased risk of bipolar disorder with psychotic features. Conclusions These results suggest that maternal influenza exposure may increase the risk for the offspring developing bipolar disorder with psychotic features. Taken together with earlier associations between prenatal influenza exposure and schizophrenia, this may suggest that prenatal influenza is a risk factor for psychosis, rather than for a specific psychotic disorder diagnosis. PMID:24480930

Juvenile hormone levels reflect social opportunities in the facultatively eusocial sweat bee Megalopta genalis (Hymenoptera: Halictidae).

PubMed

Smith, Adam R; Kapheim, Karen M; Pérez-Ortega, Betzi; Brent, Colin S; Wcislo, William T

2013-01-01

The evolution of eusociality is hypothesized to have involved de-coupling parental care from reproduction mediated by changes in endocrine regulation. While data for obligately eusocial insects are consistent with this hypothesis, we lack information from species representative of the transition from solitary reproduction to eusociality. Here we report the first evidence for a link between endocrine processes and social behavior in a facultatively eusocial bee, Megalopta genalis (Halictidae). Using females that varied in social, reproductive, and ecological context, we measured juvenile hormone (JH), a major regulator of colony caste dynamics in other eusocial species. JH was low at adult emergence, but elevated after 10 days in all nesting females. Females reared in cages with ad lib nutrition, however, did not elevate JH levels after 10 days. All reproductive females had significantly more JH than all age-matched non-reproductive females, suggesting a gonadotropic function. Among females in established nests, JH was higher in queens than workers and solitary reproductives, suggesting a role for JH in social dominance. A lack of significant differences in JH between solitary reproductives and non-reproductive workers suggests that JH content reflects more than reproductive status. Our data support the hypothesis that endocrine modifications are involved in the evolutionary decoupling of reproductive and somatic effort in social insects. These are the first measurements of JH in a solitary-nesting hymenopteran, and the first to compare eusocial and solitary nesting individuals of the same species. Published by Elsevier Inc.

Coevolutionary diversification creates nested-modular structure in phage–bacteria interaction networks

PubMed Central

Beckett, Stephen J.; Williams, Hywel T. P.

2013-01-01

Phage and their bacterial hosts are the most diverse and abundant biological entities in the oceans, where their interactions have a major impact on marine ecology and ecosystem function. The structure of interaction networks for natural phage–bacteria communities offers insight into their coevolutionary origin. At small phylogenetic scales, observed communities typically show a nested structure, in which both hosts and phages can be ranked by their range of resistance and infectivity, respectively. A qualitatively different multi-scale structure is seen at larger phylogenetic scales; a natural assemblage sampled from the Atlantic Ocean displays large-scale modularity and local nestedness within each module. Here, we show that such ‘nested-modular’ interaction networks can be produced by a simple model of host–phage coevolution in which infection depends on genetic matching. Negative frequency-dependent selection causes diversification of hosts (to escape phages) and phages (to track their evolving hosts). This creates a diverse community of bacteria and phage, maintained by kill-the-winner ecological dynamics. When the resulting communities are visualized as bipartite networks of who infects whom, they show the nested-modular structure characteristic of the Atlantic sample. The statistical significance and strength of this observation varies depending on whether the interaction networks take into account the density of the interacting strains, with implications for interpretation of interaction networks constructed by different methods. Our results suggest that the apparently complex community structures associated with marine bacteria and phage may arise from relatively simple coevolutionary origins. PMID:24516719

Fibroblast growth factor-10 signals development of von Brunn's nests in the exstrophic bladder

PubMed Central

Eastman, Rocky; Leaf, Elizabeth M.; Zhang, Dianzhong; True, Lawrence D.; Sweet, Robert M.; Seidel, Kristy; Siebert, Joseph R.; Grady, Richard; Mitchell, Michael E.

2010-01-01

von Brunn's nests have long been recognized as precursors of benign lesions of the urinary bladder mucosa. We report here that von Brunn's nests are especially prevalent in the exstrophic bladder, a birth defect that predisposes the patient to formation of bladder cancer. Cells of von Brunn's nest were found to coalesce into a stratified, polarized epithelium which surrounds itself with a capsule-like structure rich in types I, III, and IV collagen. Histocytochemical analysis and keratin profiling demonstrated that nested cells exhibited a phenotype similar, but not identical, to that of urothelial cells of transitional epithelium. Immunostaining and in situ hybridization analysis of exstrophic tissue demonstrated that the FGF-10 receptor is synthesized and retained by cells of von Brunn's nest. In contrast, FGF-10 is synthesized and secreted by mesenchymal fibroblasts via a paracrine pathway that targets basal epithelial cells of von Brunn's nests. Small clusters of 10pRp cells, positive for both FGF-10 and its receptor, were observed both proximal to and inside blood vessels in the lamina propria. The collective evidence points to a mechanism where von Brunn's nests develop under the control of the FGF-10 signal transduction system and suggests that 10pRp cells may be the original source of nested cells. PMID:20719973

Impacts of tree rows on grassland birds & potential nest predators: A removal experiment

USGS Publications Warehouse

Ellison, Kevin S.; Ribic, Christine; Sample, David W.; Fawcett, Megan J.; Dadisman, John D.

2013-01-01

Globally, grasslands and the wildlife that inhabit them are widely imperiled. Encroachment by shrubs and trees has widely impacted grasslands in the past 150 years. In North America, most grassland birds avoid nesting near woody vegetation. Because woody vegetation fragments grasslands and potential nest predator diversity and abundance is often greater along wooded edge and grassland transitions, we measured the impacts of removing rows of trees and shrubs that intersected grasslands on potential nest predators and the three most abundant grassland bird species (Henslow’s sparrow [Ammodramus henslowii], Eastern meadowlark [Sturnella magna], and bobolink [Dolichonyx oryzivorus]) at sites in Wisconsin, U.S.A. We monitored 3 control and 3 treatment sites, for 1 yr prior to and 3 yr after tree row removal at the treatment sites. Grassland bird densities increased (2–4 times for bobolink and Henslow’s sparrow) and nesting densities increased (all 3 species) in the removal areas compared to control areas. After removals, Henslow’s sparrows nested within ≤50 m of the treatment area, where they did not occur when tree rows were present. Most dramatically, activity by woodland-associated predators nearly ceased (nine-fold decrease for raccoon [Procyon lotor]) at the removals and grassland predators increased (up to 27 times activity for thirteen-lined ground squirrel [Ictidomys tridecemlineatus]). Nest success did not increase, likely reflecting the increase in grassland predators. However, more nests were attempted by all 3 species (175 versus 116) and the number of successful nests for bobolinks and Henslow’s sparrows increased. Because of gains in habitat, increased use by birds, greater production of young, and the effective removal of woodland-associated predators, tree row removal, where appropriate based on the predator community, can be a beneficial management action for conserving grassland birds and improving fragmented and degraded grassland ecosystems.

Impacts of Tree Rows on Grassland Birds and Potential Nest Predators: A Removal Experiment

PubMed Central

Ellison, Kevin S.; Ribic, Christine A.; Sample, David W.; Fawcett, Megan J.; Dadisman, John D.

2013-01-01

Globally, grasslands and the wildlife that inhabit them are widely imperiled. Encroachment by shrubs and trees has widely impacted grasslands in the past 150 years. In North America, most grassland birds avoid nesting near woody vegetation. Because woody vegetation fragments grasslands and potential nest predator diversity and abundance is often greater along wooded edge and grassland transitions, we measured the impacts of removing rows of trees and shrubs that intersected grasslands on potential nest predators and the three most abundant grassland bird species (Henslow’s sparrow [Ammodramus henslowii], Eastern meadowlark [Sturnella magna], and bobolink [Dolichonyx oryzivorus]) at sites in Wisconsin, U.S.A. We monitored 3 control and 3 treatment sites, for 1 yr prior to and 3 yr after tree row removal at the treatment sites. Grassland bird densities increased (2–4 times for bobolink and Henslow’s sparrow) and nesting densities increased (all 3 species) in the removal areas compared to control areas. After removals, Henslow’s sparrows nested within ≤50 m of the treatment area, where they did not occur when tree rows were present. Most dramatically, activity by woodland-associated predators nearly ceased (nine-fold decrease for raccoon [Procyon lotor]) at the removals and grassland predators increased (up to 27 times activity for thirteen-lined ground squirrel [Ictidomys tridecemlineatus]). Nest success did not increase, likely reflecting the increase in grassland predators. However, more nests were attempted by all 3 species (175 versus 116) and the number of successful nests for bobolinks and Henslow’s sparrows increased. Because of gains in habitat, increased use by birds, greater production of young, and the effective removal of woodland-associated predators, tree row removal, where appropriate based on the predator community, can be a beneficial management action for conserving grassland birds and improving fragmented and degraded grassland ecosystems. PMID:23565144

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.

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.

The role of leaf cutter ants on soil organic carbon dynamics in a wet tropical forest

NASA Astrophysics Data System (ADS)

Schwendenmann, L.; Meredyth-Young, M.; Dierick, D.; Allen, M. F.; Harmon, T. C.; Oberbauer, S. F.; Rundel, P.; Trahan, N. A.; Zelikova, T. J.

2016-12-01

Tropical forest ecosystems play an important role in the global carbon (C) cycle. Neotropical forests are significantly influenced by leaf cutter ants (LCA) which are the most important herbivore in these systems. LCA cut fresh leaves and bring large amounts of plant biomass into their nests to grow their fungus gardens. The excavation and continual maintenance of their large nests modifies soil characteristics and biogeochemistry with direct and indirect impacts on soil organic carbon (SOC) dynamics. The aim of this study was to quantify the effects of LCA (Atta cephalotes) on soil C mineralization, carbon degrading enzymes (β-glucosidase and α-glucosidase), and labile soil C (hot water extractable carbon) across a 1 m soil depth profile and comparing between two different soils (residual and alluvial) and forest types (primary and secondary) in a wet tropical rainforest in Costa Rica. We hypothesized that C mineralization rates will be higher inside LCA nests due to continual input of fresh organic matter, as evidenced by higher microbial biomass and carbon degrading enzymes. Similarly, we expected more labile C inside nests. All soil C parameters were highly variable among sites and between nests and controls. Carbon mineralization rates ranged from 0.02 to 0.2 µmol C h-1 g soil-1 during the initial decay phase which lasted approximately 6 days during soil incubation. The highest respiration rates were measured in the top 20 cm of the primary forest residual soil. Contrary to our expectations, C mineralization rates were higher in control soils, where C degrading enzymes were in higher concentrations (around 250 µmol). The labile soil C concentrations were variable across sites (2-25 mg C g soil-1) and higher in the upper soil profiles, but no significant differences were found between controls and nests. Our results indicate greater heterogeneity inside the nests than previously expected. We explain our findings in terms of the removal of leaf and organic matter from the nest surface by LCA, which may have led to a reduction in available carbon substrate for microbial decomposition.

Nest-site selection analysis of hooded crane (Grus monacha) in Northeastern China based on a multivariate ensemble model.

PubMed

Jiao, Shengwu; Guo, Yumin; Huettmann, Falk; Lei, Guangchun

2014-07-01

Avian nest-site selection is an important research and management subject. The hooded crane (Grus monacha) is a vulnerable (VU) species according to the IUCN Red List. Here, we present the first long-term Chinese legacy nest data for this species (1993-2010) with publicly available metadata. Further, we provide the first study that reports findings on multivariate nest habitat preference using such long-term field data for this species. Our work was carried out in Northeastern China, where we found and measured 24 nests and 81 randomly selected control plots and their environmental parameters in a vast landscape. We used machine learning (stochastic boosted regression trees) to quantify nest selection. Our analysis further included varclust (R Hmisc) and (TreenNet) to address statistical correlations and two-way interactions. We found that from an initial list of 14 measured field variables, water area (+), water depth (+) and shrub coverage (-) were the main explanatory variables that contributed to hooded crane nest-site selection. Agricultural sites played a smaller role in the selection of these nests. Our results are important for the conservation management of cranes all over East Asia and constitute a defensible and quantitative basis for predictive models.

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.

Building of nested components by a double-nozzle droplet deposition process

NASA Astrophysics Data System (ADS)

Li, SuLi; Wei, ZhengYing; Du, Jun; Zhao, Guangxi; Wang, Xin; Lu, BingHeng

2016-07-01

According to the nested components jointed with multiple parts,a double-nozzle droplet deposition process was put forward in this paper, and the experimental system was developed. Through the research on the properties of support materials and the process of double-nozzle droplet deposition, the linkage control of the metal droplet deposition and the support material extrusion was realized, and a nested component with complex construction was fabricated directly. Compared with the traditional forming processes, this double-nozzle deposition process has the advantages of short cycle, low cost and so on. It can provide an approach way to build the nested parts.

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.

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.

Polydomy in the ant Ectatomma opaciventre

PubMed Central

Tofolo, Viviane C.; Giannotti, Edilberto; Neves, Erika F.; Andrade, Luis H. C.; M. Lima, Sandro; Súarez, Yzel R.; Antonialli-Junior, William F.

2014-01-01

Abstract Tropical ants commonly exhibit a hyper-dispersed pattern of spatial distribution of nests. In polydomous species, nests may be satellites, that is, secondary structures of the main nest, where the queen is found. In order to evaluate whether the ant Ectatomma opaciventre Roger (Formicidae: Ectatomminae) uses the strategy of building polydomous nests, the spatial distribution pattern of 33 nests in a 1,800 m 2 degraded area located in Rio Claro, SP, Brazil, were investigated using the nearest neighbor method. To complement the results of this investigation, the cuticular chemical profile of eight colonies was analyzed using Fourier transform infrared photoacoustic spectrosco-py (FTIR-PAS). The nests of E. opaciventre presented a hyper-dispersed or regular distribution, which is the most common in ants. The analysis of the cuticular hydrocarbons apparently con-firmed the hypothesis that this species is polydomous, since the chemical profiles of all studied colonies with nests at different sites were very similar to the chemical signature of the single found queen and were also different from those of colonies used as control. PMID:25373168

Nesting bird "host funnel" increases mosquito-bird contact rate.

PubMed

Caillouët, Kevin A; Riggan, Anna E; Bulluck, Lesley P; Carlson, John C; Sabo, Roy T

2013-03-01

Increases in vector-host contact rates can enhance arbovirus transmission intensity. We investigated weekly fluctuations in contact rates between mosquitoes and nesting birds using the recently described Nest Mosquito Trap (NMT). The number of mosquitoes per nestling increased from < 1 mosquito per trap night to 36.2 in the final 2 wk of the nesting season. Our evidence suggests the coincidence of the end of the avian nesting season and increasing mosquito abundances may have caused a "host funnel," concentrating host-seeking mosquitoes to the few remaining nestlings. The relative abundance of mosquitoes collected by the NMT suggests that significantly more Aedes albopictus (Skuse) and Culex pipiens (L.) /restuans (Theobald) sought nesting bird bloodmeals than were predicted by their relative abundances in CO2-baited Centers for Disease Control and Prevention light and gravid traps. Culex salinarius (Coquillett) and Culex erraticus Dyar and Knab were collected in NMTs in proportion to their relative abundances in the generic traps. Temporal host funnels and nesting bird host specificity may enhance arbovirus amplification and explain observed West Nile virus and St. Louis encephalitis virus amplification periods.

Underground anemotactic orientation in leaf-cutting ants: perception of airflow and experience-dependent choice of airflow direction during digging

NASA Astrophysics Data System (ADS)

Halboth, Florian; Roces, Flavio

2017-10-01

Air exchange between the large nests of Atta vollenweideri leaf-cutting ants and the environment strongly relies on a passive, wind-induced ventilation mechanism. Air moves through nest tunnels and airflow direction depends on the location of the tunnel openings on the nest mound. We hypothesized that ants might use the direction of airflow along nest tunnels as orientation cue in the context of climate control, as digging workers might prefer to broaden or to close tunnels with inflowing or outflowing air in order to regulate nest ventilation. To investigate anemotactic orientation in Atta vollenweideri, we first tested the ants' ability to perceive air movements by confronting single workers with airflow stimuli in the range 0 to 20 cm/s. Workers responded to airflow velocities ≥ 2 cm/s, and the number of ants reacting to the stimulus increased with increasing airflow speed. Second, we asked whether digging workers use airflow direction as an orientation cue. Workers were exposed to either inflow or outflow of air while digging in the nest and could subsequently choose between two digging sites providing either inflow or outflow of air, respectively. Workers significantly chose the side with the same airflow direction they experienced before. When no airflow was present during initial digging, workers showed no preference for airflow directions. Workers developed preferences for airflow direction only after previous exposure to a given airflow direction. We suggest that experience-modified anemotaxis might help leaf-cutting ants spatially organize their digging activity inside the nest during tasks related to climate control.

Underground anemotactic orientation in leaf-cutting ants: perception of airflow and experience-dependent choice of airflow direction during digging.

PubMed

Halboth, Florian; Roces, Flavio

2017-09-19

Air exchange between the large nests of Atta vollenweideri leaf-cutting ants and the environment strongly relies on a passive, wind-induced ventilation mechanism. Air moves through nest tunnels and airflow direction depends on the location of the tunnel openings on the nest mound. We hypothesized that ants might use the direction of airflow along nest tunnels as orientation cue in the context of climate control, as digging workers might prefer to broaden or to close tunnels with inflowing or outflowing air in order to regulate nest ventilation. To investigate anemotactic orientation in Atta vollenweideri, we first tested the ants' ability to perceive air movements by confronting single workers with airflow stimuli in the range 0 to 20 cm/s. Workers responded to airflow velocities ≥ 2 cm/s, and the number of ants reacting to the stimulus increased with increasing airflow speed. Second, we asked whether digging workers use airflow direction as an orientation cue. Workers were exposed to either inflow or outflow of air while digging in the nest and could subsequently choose between two digging sites providing either inflow or outflow of air, respectively. Workers significantly chose the side with the same airflow direction they experienced before. When no airflow was present during initial digging, workers showed no preference for airflow directions. Workers developed preferences for airflow direction only after previous exposure to a given airflow direction. We suggest that experience-modified anemotaxis might help leaf-cutting ants spatially organize their digging activity inside the nest during tasks related to climate control.

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.

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

Clinical risk factors for death after release from prison in Washington State: A nested case control study

PubMed Central

Binswanger, Ingrid A.; Stern, Marc F.; Yamashita, Traci E.; Mueller, Shane R.; Baggett, Travis P.; Blatchford, Patrick J.

2015-01-01

Background and aims While mortality rates after prison release are high, little is known about clinical risk factors for death. We sought to identify risk and protective factors for all-cause and accidental poisoning (overdose) death. Design Nested case control study of people released from prison. Setting Washington State Department of Corrections, Washington, USA. Participants Cases (699 all-cause deaths, of which 88 were among women, and 206 additional overdose deaths, of which 76 were among women) between 1999 and 2009 matched 1:1 to controls on sex, age and year of release using risk set sampling. Measurements Prison medical charts were abstracted for clinical information. Independent associations between clinical characteristics and all-cause and overdose mortality were assessed using conditional logistic regression. Findings Key independent risk factors for all-cause mortality included homelessness (Odds Ratio [OR] 1.53, 95% Confidence Interval [CI] 1.06, 2.23), injection drug use (OR 1.54, 95% CI 1.15, 2.05), tobacco use (OR 1.50, 95% CI 1.06, 2.12), cirrhosis (OR 4.42, 95% CI 1.63, 11.98), and psychiatric medications before release (OR 2.37, 95% CI 1.71, 3.29). Independent risk factors for overdose mortality included substance dependence (OR 2.33, 95% CI 1.32, 4.11), injection drug use (OR 2.43, 95% CI 1.53, 3.86), panic disorder (OR 3.87, 95% CI 1.62, 9.21), psychiatric prescriptions before release (OR 2.44, 95% CI 1.55, 3.85), and problems with opiates/sedatives (OR 2.81, 95% CI 1.40, 5.63). Substance use disorder treatment during the index incarceration was protective for all-cause (OR 0.67, 95% CI 0.49, 0.91) and overdose (OR 0.57, 95% CI 0.35, 0.90) mortality. Conclusions Injection drug use and substance use disorders are risk factors for death after release from prison. In-prison substance use treatment services may reduce the risk. PMID:26476210

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.

Calcium Channel Blockers in Secondary Cardiovascular Prevention and Risk of Acute Events: Real-World Evidence from Nested Case-Control Studies on Italian Hypertensive Elderly.

PubMed

Bettiol, Alessandra; Lucenteforte, Ersilia; Vannacci, Alfredo; Lombardi, Niccolò; Onder, Graziano; Agabiti, Nera; Vitale, Cristiana; Trifirò, Gianluca; Corrao, Giovanni; Roberto, Giuseppe; Mugelli, Alessandro; Chinellato, Alessandro

2017-12-01

Antihypertensive treatment with calcium channel blockers (CCBs) is consolidated in clinical practice; however, different studies observed increased risks of acute events for short-acting CCBs. This study aimed to provide real-world evidence on risks of acute cardiovascular (CV) events, hospitalizations and mortality among users of different CCB classes in secondary CV prevention. Three case-control studies were nested in a cohort of Italian elderly hypertensive CV-compromised CCBs users. Cases were subjects with CV events (n = 25,204), all-cause hospitalizations (n = 19,237), or all-cause mortality (n = 17,996) during the follow-up. Up to four controls were matched for each case. Current or past exposition to CCBs at index date was defined based on molecule, formulation and daily doses of the last CCB delivery. The odds ratio (OR) and 95% confidence intervals (CI) were estimated using conditional logistic regression models. Compared to past users, current CCB users had significant reductions in risks of CV events [OR 0.88 (95% CI: 0.84-0.91)], hospitalization [0.90 (0.88-0.93)] and mortality [0.48 (0.47-0.49)]. Current users of long-acting dihydropyridines (DHPs) had the lowest risk [OR 0.87 (0.84-0.90), 0.86 (0.83-0.90), 0.55 (0.54-0.56) for acute CV events, hospitalizations and mortality], whereas current users of short-acting CCBs had an increased risk of acute CV events [OR 1.77 (1.13-2.78) for short-acting DHPs; 1.19 (1.07-1.31) for short-acting non-DHPs] and hospitalizations [OR 1.84 (0.96-3.51) and 1.23 (1.08-1.42)]. The already-existing warning on short-acting CCBs should be potentiated, addressing clinicians towards the choice of long-acting formulations.

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.

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.

A nested case-control study of polychlorinated biphenyls, organochlorine pesticides, and thyroid cancer in the Janus Serum Bank cohort.

PubMed

Lerro, Catherine C; Jones, Rena R; Langseth, Hilde; Grimsrud, Tom K; Engel, Lawrence S; Sjödin, Andreas; Choo-Wosoba, Hyoyoung; Albert, Paul; Ward, Mary H

2018-04-23

Polychlorinated biphenyls (PCBs) and organochlorine pesticides have been associated with altered thyroid hormone levels in humans, but their relationship with thyroid cancer is unknown. We conducted a nested case-control study of thyroid cancer in the Norwegian Janus Serum Bank cohort using pre-diagnostic blood samples from 1972 to 1985. Incident thyroid cancer (n = 108) was ascertained through 2008. Controls were matched 2:1 by age, date of blood draw, gender, and county. We used gas chromatography/mass spectrometry to quantify 36 PCB congeners and metabolites of pesticides DDT, chlordane, hexachlorocyclohexane, and hexachlorobenzene. PCBs and pesticide metabolites were evaluated individually and summed by degree of chlorination and parent compound, respectively. Odds ratios (OR) and 95% confidence intervals (CI) were computed using conditional logistic regression per specified increase in lipid-adjusted concentration. We additionally stratified analyses by birth cohort (1923-1932, 1933-1942, 1943-1957). Increasing concentration of DDT metabolites (OR per 1000 ng/g = 0.80, 95%CI = 0.66-0.98) was inversely associated with thyroid cancer. Associations for PCBs were null or in inverse direction. We observed interactions for total PCBs, moderately-chlorinated PCBs, and chlordane metabolites with birth cohort (p ≤ 0.04). Among participants born 1943-1957, total PCBs (OR per 100 ng/g = 1.25, 95%CI = 1.00-1.56), moderately-chlorinated PCBs (OR per 100 ng/g = 1.31, 95%CI = 1.01-1.70), and chlordane metabolites (OR per 10 ng/g = 1.78, 95%CI = 1.09-2.93) were positively associated with thyroid cancer. For individuals born before 1943, associations were generally null or in the inverse direction. Emissions of PCBs and OC pesticides varied over time. Different risk patterns by birth cohort suggest the potential importance of timing of exposure in thyroid cancer risk. Further evaluation of these associations is warranted. Published by Elsevier Inc.

Plasma carotenoids, vitamin C, retinol and tocopherols levels and pancreatic cancer risk within the European Prospective Investigation into Cancer and Nutrition: a nested case-control study: plasma micronutrients and pancreatic cancer risk.

PubMed

Jeurnink, Suzanne M; Ros, Martine M; Leenders, Max; van Duijnhoven, Franzel J B; Siersema, Peter D; Jansen, Eugene H J M; van Gils, Carla H; Bakker, Marije F; Overvad, Kim; Roswall, Nina; Tjønneland, Anne; Boutron-Ruault, Marie-Christine; Racine, Antoine; Cadeau, Claire; Grote, Verena; Kaaks, Rudolf; Aleksandrova, Krasimira; Boeing, Heiner; Trichopoulou, Antonia; Benetou, Vasiliki; Valanou, Elisavet; Palli, Domenico; Krogh, Vittorio; Vineis, Paolo; Tumino, Rosario; Mattiello, Amalia; Weiderpass, Elisabete; Skeie, Guri; Castaño, José María Huerta; Duell, Eric J; Barricarte, Aurelio; Molina-Montes, Esther; Argüelles, Marcial; Dorronsoro, Mire; Johansen, Dorthe; Lindkvist, Björn; Sund, Malin; Crowe, Francesca L; Khaw, Kay-Tee; Jenab, Mazda; Fedirko, Veronika; Riboli, E; Bueno-de-Mesquita, H B

2015-03-15

Evidence of a protective effect of several antioxidants and other nutrients on pancreatic cancer risk is inconsistent. The aim of this study was to investigate the association for prediagnostic plasma levels of carotenoids, vitamin C, retinol and tocopherols with risk of pancreatic cancer in a case-control study nested within the European Prospective Investigation into Cancer and Nutrition (EPIC). 446 incident exocrine pancreatic cancer cases were matched to 446 controls by age at blood collection, study center, sex, date and time of blood collection, fasting status and hormone use. Plasma carotenoids (α- and β-carotene, lycopene, β-cryptoxanthin, canthaxanthin, zeaxanthin and lutein), α- and γ-tocopherol and retinol were measured by reverse phase high-performance liquid chromatography and plasma vitamin C by a colorimetric assay. Incidence rate ratios (IRRs) with 95% confidence intervals (95%CIs) for pancreatic cancer risk were estimated using a conditional logistic regression analysis, adjusted for smoking status, smoking duration and intensity, waist circumference, cotinine levels and diabetes status. Inverse associations with pancreatic cancer risk were found for plasma β-carotene (IRR highest vs. lowest quartile 0.52, 95%CI 0.31-0.88, p for trend = 0.02), zeaxanthin (IRR highest vs. lowest quartile 0.53, 95%CI 0.30-0.94, p for trend = 0.06) and α-tocopherol (IRR highest vs. lowest quartile 0.62, 95%CI 0.39-0.99, p for trend = 0.08. For α- and β-carotene, lutein, sum of carotenoids and γ-tocopherol, heterogeneity between geographical regions was observed. In conclusion, our results show that higher plasma concentrations of β-carotene, zeaxanthin and α-tocopherol may be inversely associated with risk of pancreatic cancer, but further studies are warranted. © 2014 UICC.

Risk factors for hyperkalaemia in a cohort of patients with newly diagnosed heart failure: a nested case-control study in UK general practice.

PubMed

Michel, Alexander; Martín-Pérez, Mar; Ruigómez, Ana; García Rodríguez, Luis A

2015-02-01

The aim of this study was to identify risk factors for hyperkalaemia in a cohort of patients with newly diagnosed heart failure in the UK. A nested case-control study was conducted using data from The Health Improvement Network primary care database. A cohort of 19 194 patients aged 1-89 years between January 2000 and December 2005 with newly diagnosed heart failure was followed up and cases of hyperkalaemia identified. Cases were frequency matched to controls by age, sex, and calendar year, and information on demographics, co-morbidities, co-medications, and lifestyle factors was extracted from the database. Using unconditional logistic regression models, odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to identify potential risk factors. In total, 2176 hyperkalaemia cases were identified over a mean follow-up of 3.9 years. Significant risk factors for hyperkalaemia were: renal failure (OR 3.81; 95% CI 3.29-4.42), type II diabetes (OR 1.52; 95% CI 1.31-1.75), valvular heart disease (OR 1.28; 95% CI 1.06-1.54), and current use of potassium-sparing diuretics (OR 3.01; 95% CI 2.61-3.48), ACE inhibitors (OR 1.70; 95% CI 1.41-2.04), trimethoprim (OR 2.82; 95% CI 1.88-4.23), non-steroidal anti-inflammatory drugs (OR 1.41; 95% CI 1.11-1.79), and several drug combinations. The risk was highest within the first month of medication use and decreased thereafter. Our findings may help to better identify patients with heart failure most likely to benefit from careful monitoring of serum potassium levels. Particular vigilance is needed during the start of treatment with certain medications. © 2015 The Authors. European Journal of Heart Failure © 2015 European Society of Cardiology.

Polymorphisms of genes coding for ghrelin and its receptor in relation to anthropometry, circulating levels of IGF-I and IGFBP-3, and breast cancer risk: a case-control study nested within the European Prospective Investigation into Cancer and Nutrition (EPIC).

PubMed

Dossus, Laure; McKay, James D; Canzian, Federico; Wilkening, Stefan; Rinaldi, Sabina; Biessy, Carine; Olsen, Anja; Tjønneland, Anne; Jakobsen, Marianne U; Overvad, Kim; Clavel-Chapelon, Françoise; Boutron-Ruault, Marie-Christine; Fournier, Agnes; Linseisen, Jakob; Lukanova, Annekatrin; Boeing, Heiner; Fisher, Eva; Trichopoulou, Antonia; Georgila, Christina; Trichopoulos, Dimitrios; Palli, Domenico; Krogh, Vittorio; Tumino, Rosario; Vineis, Paolo; Quirós, José Ramon; Sala, Núria; Martínez-García, Carmen; Dorronsoro, Miren; Chirlaque, Maria-Dolores; Barricarte, Aurelio; van Duijnhoven, Fränzel J B; Bueno-de-Mesquita, H B; van Gils, Carla H; Peeters, Petra H M; Hallmans, Göran; Lenner, Per; Bingham, Sheila; Khaw, Kay Tee; Key, Tim J; Travis, Ruth C; Ferrari, Pietro; Jenab, Mazda; Riboli, Elio; Kaaks, Rudolf

2008-07-01

Ghrelin, an endogenous ligand for the growth hormone secretagogue receptor, has two major functions: the stimulation of the growth hormone production and the stimulation of food intake. Accumulating evidence also suggests a role of ghrelin in cancer development. We conducted a case-control study on 1359 breast cancer cases and 2389 matched controls, nested within the European Prospective Investigation into Cancer and Nutrition, to examine the association of common genetic variants in the genes coding for ghrelin (GHRL) and its receptor (GHSR) with anthropometric measures, circulating insulin growth factor I (IGF-I) and insulin-like growth factor-binding protein 3 and breast cancer risk. Pair-wise tagging was used to select the 15 polymorphisms that represent the majority of common genetic variants across the GHRL and GHSR genes. A significant increase in breast cancer risk was observed in carriers of the GHRL rs171407-G allele (odds ratio: 1.2; 95% confidence interval: 1.0-1.4; P = 0.02). The GHRL single-nucleotide polymorphism rs375577 was associated with a 5% increase in IGF-I levels (P = 0.01). A number of GHRL and GHSR polymorphisms were associated with body mass index (BMI) and height (P between <0.01 and 0.04). The false-positive report probability (FPRP) approach suggests that these results are noteworthy (FPRP < 0.20). The results presented here add to a growing body of evidence that GHRL variations are associated with BMI. Furthermore, we have observed evidence for association of GHRL polymorphisms with circulating IGF-I levels and with breast cancer risk. These associations, however, might also be due to chance findings and further large studies are needed to confirm our results.

Regular Use of Aspirin or Non-Aspirin Nonsteroidal Anti-Inflammatory Drugs Is Not Associated With Risk of Incident Pancreatic Cancer in Two Large Cohort Studies.

PubMed

Khalaf, Natalia; Yuan, Chen; Hamada, Tsuyoshi; Cao, Yin; Babic, Ana; Morales-Oyarvide, Vicente; Kraft, Peter; Ng, Kimmie; Giovannucci, Edward; Ogino, Shuji; Stampfer, Meir; Cochrane, Barbara B; Manson, JoAnn E; Clish, Clary B; Chan, Andrew T; Fuchs, Charles S; Wolpin, Brian M

2018-04-01

Use of aspirin and/or non-aspirin nonsteroidal anti-inflammatory drugs (NSAIDs) reduces the risk of several cancers, but it is not clear if use of these drugs is associated with risk of pancreatic cancer. We evaluated aspirin and non-aspirin NSAID use and risk of pancreatic adenocarcinoma in 141,940 participants from the Health Professionals Follow-up Study and Nurses' Health Study using multivariable-adjusted Cox proportional hazards regression. We considered several exposure classifications to model differing lag times between NSAID exposure and cancer development. We also conducted a nested case-control study of participants from 3 prospective cohorts using conditional logistic regression to evaluate pre-diagnosis levels of plasma salicylurate, a major metabolite of aspirin, in 396 pancreatic cancer cases and 784 matched individuals without pancreatic cancer (controls). In the prospective cohort study, 1122 participants developed pancreatic adenocarcinoma over 4.2 million person-years. Use of aspirin or non-aspirin NSAIDs was not associated with pancreatic cancer risk, even after considering several latency exposure classifications. In a pre-planned subgroup analysis, regular aspirin use was associated with reduced pancreatic cancer risk among participants with diabetes (relative risk, 0.71; 95% CI, 0.54-0.94). In the nested case-control study, pre-diagnosis levels of salicylurate were not associated with pancreatic cancer risk (odds ratio, 1.08; 95% CI, 0.72-1.61; P trend 0.81; comparing participants in the highest quintile with those in the lowest quintile of plasma salicylurate). Regular aspirin or non-aspirin NSAID use was not associated with future risk of pancreatic cancer in participants from several large prospective cohort studies. A possible reduction in risk for pancreatic cancer among people with diabetes who regularly use aspirin should be further examined in preclinical and human studies. Copyright © 2018 AGA Institute. Published by Elsevier Inc. All rights reserved.

Intensity of factor VIII treatment and the development of inhibitors in non-severe hemophilia A patients: results of the INSIGHT case-control study.

PubMed

van Velzen, A S; Eckhardt, C L; Peters, M; Leebeek, F W G; Escuriola-Ettingshausen, C; Hermans, C; Keenan, R; Astermark, J; Male, C; Peerlinck, K; le Cessie, S; van der Bom, J G; Fijnvandraat, K

2017-07-01

Essentials Research suggests that intensive treatment episodes may increase the risk to develop inhibitors. We performed an international nested case-control study with 298 non-severe hemophilia A patients. Surgery and a high dose of factor VIII concentrate were associated with increased inhibitor risk. Physicians need to review arguments for factor VIII dose and elective surgery extra critically. Background Inhibitor development is a major complication of treatment with factor VIII concentrates in hemophilia. Findings from studies among severe hemophilia A patients suggest that intensive treatment episodes increase the risk of developing inhibitors. Objectives We set out to assess whether intensive treatment is also associated with an increased risk of inhibitor development among non-severe hemophilia A patients. Patients/Methods We performed a nested case-control study. A total of 75 inhibitor patients (cases) and 223 control patients were selected from 2709 non-severe hemophilia A patients (FVIII:C, 2-40%) of the INSIGHT cohort study. Cases and controls were matched for date of birth and cumulative number of exposure days (EDs) to FVIII concentrates. Conditional logistic regression was used to calculate both unadjusted and adjusted odds ratios (aOR); the latter were adjusted for a priori specified confounders. Results Peak treatment of 5 or 10 consecutive EDs did not increase inhibitor risk (aOR, 1.0; 95% confidence interval (CI), 0.4-2.5; and aOR, 1.8; CI, 0.6-5.5, respectively). Both surgical intervention (aOR, 4.2; CI, 1.7-10.3) and a high mean dose (> 45 IU kg -1 /ED) of FVIII concentrate (aOR, 7.5; CI, 1.6-35.6) were associated with an increased inhibitor risk. Conclusions Our findings suggest that high-dose FVIII treatment and surgery increase the risk of inhibitor development in non-severe hemophilia A. Together with the notion that non-severe hemophilia A patients are at a lifelong risk of inhibitor development, we suggest that in the future physicians will review the arguments for the FVIII dose and elective surgery extra critically. © 2017 International Society on Thrombosis and Haemostasis.

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

PubMed

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

2016-08-26

This study aims to assess the needs of people with disabilities and their level of inclusion in social protection programmes. Population based-survey with a nested case-control study. Morropon, a semiurban district located in Piura, northern Peru. 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. 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. 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. 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. 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/

The Influence of Hormonal Factors on the Risk of Developing Cervical Cancer and Pre-Cancer: Results from the EPIC Cohort

PubMed Central

Roura, Esther; Travier, Noémie; Waterboer, Tim; de Sanjosé, Silvia; Bosch, F. Xavier; Pawlita, Michael; Pala, Valeria; Weiderpass, Elisabete; Margall, Núria; Dillner, Joakim; Gram, Inger T.; Tjønneland, Anne; Munk, Christian; Palli, Domenico; Khaw, Kay-Tee; Overvad, Kim; Clavel-Chapelon, Françoise; Mesrine, Sylvie; Fournier, Agnès; Fortner, Renée T.; Ose, Jennifer; Steffen, Annika; Trichopoulou, Antonia; Lagiou, Pagona; Orfanos, Philippos; Masala, Giovanna; Tumino, Rosario; Sacerdote, Carlotta; Polidoro, Silvia; Mattiello, Amalia; Lund, Eiliv; Peeters, Petra H.; Bueno-de-Mesquita, H. B(as).; Quirós, J. Ramón; Sánchez, María-José; Navarro, Carmen; Barricarte, Aurelio; Larrañaga, Nerea; Ekström, Johanna; Lindquist, David; Idahl, Annika; Travis, Ruth C.; Merritt, Melissa A.; Gunter, Marc J.; Rinaldi, Sabina; Tommasino, Massimo; Franceschi, Silvia; Riboli, Elio; Castellsagué, Xavier

2016-01-01

Background In addition to HPV, high parity and hormonal contraceptives have been associated with cervical cancer (CC). However, most of the evidence comes from retrospective case-control studies. The aim of this study is to prospectively evaluate associations between hormonal factors and risk of developing cervical intraepithelial neoplasia grade 3 (CIN3)/carcinoma in situ (CIS) and invasive cervical cancer (ICC). Methods and Findings We followed a cohort of 308,036 women recruited in the European Prospective Investigation into Cancer and Nutrition (EPIC) Study. At enrollment, participants completed a questionnaire and provided serum. After a 9-year median follow-up, 261 ICC and 804 CIN3/CIS cases were reported. In a nested case-control study, the sera from 609 cases and 1,218 matched controls were tested for L1 antibodies against HPV types 11,16,18,31,33,35,45,52,58, and antibodies against Chlamydia trachomatis and Human herpesvirus 2. Multivariate analyses were performed to estimate hazard ratios (HR), odds ratios (OR) and corresponding 95% confidence intervals (CI). The cohort analysis showed that number of full-term pregnancies was positively associated with CIN3/CIS risk (p-trend = 0.03). Duration of oral contraceptives use was associated with a significantly increased risk of both CIN3/CIS and ICC (HR = 1.6 and HR = 1.8 respectively for ≥15 years versus never use). Ever use of menopausal hormone therapy was associated with a reduced risk of ICC (HR = 0.5, 95%CI: 0.4–0.8). A non-significant reduced risk of ICC with ever use of intrauterine devices (IUD) was found in the nested case-control analysis (OR = 0.6). Analyses restricted to all cases and HPV seropositive controls yielded similar results, revealing a significant inverse association with IUD for combined CIN3/CIS and ICC (OR = 0.7). Conclusions Even though HPV is the necessary cause of CC, our results suggest that several hormonal factors are risk factors for cervical carcinogenesis. Adherence to current cervical cancer screening guidelines should minimize the increased risk of CC associated with these hormonal risk factors. PMID:26808155

Nest-site selection and hatching success of waterbirds in coastal Virginia: some results of habitat manipulation

USGS Publications Warehouse

Rounds, R.A.; Erwin, R.M.; Portera, J.H.

2004-01-01

Rising sea levels in the mid-Atlantic region pose a long-term threat to marshes and their avian inhabitants. The Gull-billed Tern (Sterna nilotica), Common Tern (S. hirundo), Black Skimmer (Rynchops niger), and American Oystercatcher (Haematopus palliatus), species of concern in Virginia, nest on low shelly perimeters of salt marsh islands on the Eastern Shore of Virginia. Marsh shellpiles are free of mammalian predators, but subject to frequent floods that reduce reproductive success. In an attempt to examine nest-site selection, enhance habitat, and improve hatching success, small (2 ? 2 m) plots on five island shellpiles were experimentally elevated, and nest-site selection and hatching success were monitored from 1 May to 1 August, 2002. In addition, location, elevation, and nesting performance of all other nests in the colonies were also monitored. No species selected the elevated experimental plots preferentially over adjacent control plots at any of the sites. When all nests were considered, Common Tern nests were located significantly lower than were random point elevations at two sites, as they tended to concentrate on low-lying wrack. At two other sites, however, Common Tern nests were significantly higher than were random points. Gull-billed Terns and American Oystercatchers showed a weak preference for higher elevations on bare shell at most sites. Hatching success was not improved on elevated plots, despite the protection they provided from flooding. Because of a 7 June flood, when 47% of all nests flooded, hatching success for all species was low. Nest elevation had the strongest impact on a nest's probability of hatching, followed by nest-initiation date. Predation rates were high at small colonies, and Ruddy Turnstones (Arenaria interpres) depredated 90% of early Gull-billed Tern nests at one shellpile. The importance of nest elevation and flooding on hatching success demonstrates the potential for management of certain waterbird nesting sites. Facing threats from predators on barrier islands and rising sea levels especially in the mid-Atlantic region, several species of nesting waterbirds may benefit dramatically with modest manipulation of even small habitat patches on isolated marsh islands.

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.

Central Nervous System Medication Burden and Serious Falls in Older Nursing Home Residents

PubMed Central

Hanlon, Joseph T.; Zhao, Xinhua; Naples, Jennifer G.; Aspinall, Sherrie L.; Perera, Subashan; Nace, David A.; Castle, Nicholas G.; Greenspan, Susan L.; Thorpe, Carolyn T.

2016-01-01

Objectives To examine the association between CNS medication burden and serious falls in those with a recent fall history. Design Nested-case control study; cases matched to four controls by age, gender, and date. Setting US nursing homes Participants 5,556 residents age ≥ 65 with a recent fall history admitted to a nursing home between 1/1–9/30/2010 and followed until discharge, death, or 12/31/2010. Measurements Outcome was serious falls as per Medicare Part A and B ICD/CPT codes. CNS burden, from Medicare Part D data, was calculated by dividing the daily dose of each CNS agent (i.e., specific antidepressants, antiepileptic, antipsychotic, benzodiazepine and opioid receptor agonists) received during the six days prior to the index (outcome) date by the minimum effective geriatric daily dose and summing the results across medications. Results There were 367 cases and 1468 matched controls. Those taking 3+ CNS standardized daily doses were more likely to have a serious fall than those not taking any CNS medications (Adjusted Odds Ratio 1.83; 95% confidence interval 1.35–2.48). There was no significant difference in fall risk for residents taking >0 to <3 CNS standardized daily doses compared to residents taking no CNS medications (Adjusted Odds Ratio 0.85; 95% CI 0.63–1.15). Conclusion CNS medication burden, approximately 3+ standardized daily doses, was associated with an increased risk of serious falls in nursing home residents with recent fall. Clinicians should be vigilant for opportunities to discontinue or decrease the doses of individual CNS medications and/or consider non-pharmacological alternatives. Such interventions that reduce use of CNS medications in nursing homes could reduce fall rates but further research is needed to confirm this. PMID:28152179

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

Correlation between cognitive impairment during the acute phase of first cerebral infarction and development of long-term pseudobulbar affect

PubMed Central

Wang, Yuan; Wang, Yuliang; Ma, Wenbin; Lu, Shujun; Chen, Jinbo; Cao, Lili

2018-01-01

Purpose The relationship between cognitive impairment during the acute phase of first cerebral infarction and the development of long-term pseudobulbar affect (PBA) has not been elucidated. Therefore, in this study, we aimed to determine if cognitive impairment during the acute phase of cerebral infarction will increase the risk of long-term post-infarction PBA. Patients and methods This was a nested case–control study using a prospective approach. A consecutive multicenter matched 1:1 case–control study of cognitive impairment cases following acute cerebral infarction (N=26) with 26 sex-, education years-, and age-matched controls. Univariate and multivariate conditional logistic regression analyses were performed to study the clinical features and changes in cognitive domain as well as the risk factors for PBA. Results Long-term PBA was independently predicted by low Montreal cognitive assessment (MoCA) scores at baseline. Multivariable regression models showed that post-infarction low MoCA scores remained independent predictors of long-term PBA (odds ratio [OR]=0.72; 95% confidence interval [CI]=0.54–0.95; P=0.018). Among all cognitive disorders, digit span test (DST) scores (OR=0.39; 95% CI=0.16–0.91, P=0.030), StroopC time (OR=1.15; 95% CI=1.01–1.31; P=0.037), and clock-drawing task (CDT) scores (OR=0.62; 95% CI=0.42–0.90; P=0.013) were found to be the independent risk factors for PBA. Conclusion Cognitive impairment during the acute phase of cerebral infarction increased the risk of cerebral infarction-induced long-term PBA. Development of PBA was closely associated with executive function, attention, and visuospatial disorder. PMID:29636612

Correlation between cognitive impairment during the acute phase of first cerebral infarction and development of long-term pseudobulbar affect.

PubMed

Wang, Yuan; Wang, Yuliang; Ma, Wenbin; Lu, Shujun; Chen, Jinbo; Cao, Lili

2018-01-01

The relationship between cognitive impairment during the acute phase of first cerebral infarction and the development of long-term pseudobulbar affect (PBA) has not been elucidated. Therefore, in this study, we aimed to determine if cognitive impairment during the acute phase of cerebral infarction will increase the risk of long-term post-infarction PBA. This was a nested case-control study using a prospective approach. A consecutive multicenter matched 1:1 case-control study of cognitive impairment cases following acute cerebral infarction (N=26) with 26 sex-, education years-, and age-matched controls. Univariate and multivariate conditional logistic regression analyses were performed to study the clinical features and changes in cognitive domain as well as the risk factors for PBA. Long-term PBA was independently predicted by low Montreal cognitive assessment (MoCA) scores at baseline. Multivariable regression models showed that post-infarction low MoCA scores remained independent predictors of long-term PBA (odds ratio [OR]=0.72; 95% confidence interval [CI]=0.54-0.95; P =0.018). Among all cognitive disorders, digit span test (DST) scores (OR=0.39; 95% CI=0.16-0.91, P =0.030), StroopC time (OR=1.15; 95% CI=1.01-1.31; P =0.037), and clock-drawing task (CDT) scores (OR=0.62; 95% CI=0.42-0.90; P =0.013) were found to be the independent risk factors for PBA. Cognitive impairment during the acute phase of cerebral infarction increased the risk of cerebral infarction-induced long-term PBA. Development of PBA was closely associated with executive function, attention, and visuospatial disorder.

Circulating cadmium concentration and risk of aortic aneurysms: A nested case-control study within the Malmö Diet and Cancer cohort.

PubMed

Fagerberg, Björn; Borné, Yan; Sallsten, Gerd; Smith, J Gustav; Acosta, Stefan; Persson, Margaretha; Melander, Olle; Forsgard, Niklas; Gottsäter, Anders; Hedblad, Bo; Barregard, Lars; Engström, Gunnar

2017-06-01

Diet and smoking expose the general population to cadmium (Cd), which is a toxic metal that accumulates in the arterial wall. In experimental studies, Cd causes reductions in proliferation of smooth muscle cells and cellular synthesis of procollagen. The aim of this study was to examine whether blood Cd levels, a valid measure of Cd exposure, are associated with increased risk of abdominal aortic aneurysm (AAA). All middle-aged men and women enrolled in the Malmö Diet and Cancer study (n = 30 447) were followed from the baseline examination in 1991-1996 through 2009. A total of 297 cases with AAA and two randomly selected control subjects for each case, matched for age and sex, were included. Blood Cd was analysed by inductively coupled plasma mass spectrometry. Diagnoses of AAA, thoracic aortic aneurysm and aortic dissection were obtained from registers. Increased blood Cd was associated with increased risk of incident AAA after adjustment for smoking and other established risk factors for AAA. The highest tertile of blood Cd concentrations had a rate ratio of 2.5 (95% confidence interval 1.3, 5.0) for incident AAA. Concentration of blood Cd (log transformed) was not associated with AAA in never-smokers (n = 24). Blood Cd levels corresponding to the upper tertile of the distribution in the age- and sex-matched control group were associated with a 2.5-fold increase in rate ratio for incident AAA. This relationship was not found in the small group of never-smokers. Copyright © 2017. Published by Elsevier B.V.

Dietary vitamin A and lung cancer: results of a case-control study among chemical workers.

PubMed

Bond, G G; Thompson, F E; Cook, R R

1987-01-01

A nested case-control study conducted among a cohort of chemical manufacturing employees provided an opportunity to test the hypothesis that lung cancer risk is inversely related to dietary intake of vitamin A. Eligible for study were 308 former male employees who had died of lung cancer between 1940 and 1980. Two control groups, one a decedent and the other a "living" series, were individually matched to the cases one-for-one. Interviews were completed with 734 subjects or their next-of-kin and included a food frequency list. A vitamin A index was developed for each subject based on the frequency of consumption of 29 food items. After adjustment for a number of potentially confounding variables (e.g., smoking, educational level, and use of vitamin supplements), there was evidence that vitamin A intake was inversely associated with lung cancer risk. The effect was most pronounced in the comparisons with the "living" controls and appeared strongest among cigarette smokers. Subjects in the lowest tertile of vitamin A intake had approximately twice the risk of lung cancer as those in the highest. Analyses of an index of carotenoids and of individual food items suggested that plant sources of vitamin A may play a more important role in producing the effect than do animal sources.

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

Using Cluster Bootstrapping to Analyze Nested Data with a Few Clusters

ERIC Educational Resources Information Center

Huang, Francis L.

2018-01-01

Cluster randomized trials involving participants nested within intact treatment and control groups are commonly performed in various educational, psychological, and biomedical studies. However, recruiting and retaining intact groups present various practical, financial, and logistical challenges to evaluators and often, cluster randomized trials…

Nesting ecology of a population of Gopherus agassizii at a utility-scale wind energy facility in southern California

USGS Publications Warehouse

Ennen, Joshua R.; Lovich, Jeffrey E.; Meyer, Katherin P.; Bjurlin, Curtis; Arundel, Terence R.

2012-01-01

We investigated the annual nesting ecology of a population of Desert Tortoises (Gopherus agassizii) inhabiting a utility-scale renewable energy (USRE) facility in southern California and compared our results with populations inhabiting relatively undisturbed sites. In 2000, 15 radio-tracked females produced 29 clutches, and 24 nests were monitored to examine nest-site selection, nest predation, hatching success, date of emergence of hatchlings, and hatchling mass and carapace length. Overall, the nesting ecology of the population inhabiting the USRE facility was very similar to other populations of Desert Tortoises inhabiting relatively undisturbed habitats. Oviposition occurred from 12 May to 8 July, which was similar to other sites. Nest depths (11.1 cm), nest predation (12%), hatchling emergence date (7 August and 29 September), and hatchling morphometrics (i.e., MCL: 44.5 mm; mass: 23 g) were all within ranges reported in other populations. Unlike within other populations, we observed no relationship between hatchling size and either maternal body size or egg width. We found no evidence of females selecting for a particular burrow for oviposition of eggs based on environmental or anthropogenic variables. Most nests were located in or near burrows, and nest depth was greater for nests near the entrance than those deeper in the burrow. Although this study suggests that the nesting ecology of the Desert Tortoise population we studied was not adversely affected by the USRE facility, this relationship is only correlative because our study was not a before-after-control-impact (BACI) study, which would establish a cause and effect relationship. As pointed out in a recent review, BACI studies are critically needed to address the wildlife impacts of utility-scale renewable energy development.

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

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.

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.

Influences of Species Interactions With Aggressive Ants and Habitat Filtering on Nest Colonization and Community Composition of Arboreal Twig-Nesting Ants.

PubMed

Philpott, Stacy M; Serber, Zachary; De la Mora, Aldo

2018-04-05

Ant community assembly is driven by many factors including species interactions (e.g., competition, predation, parasitism), habitat filtering (e.g., vegetation differences, microclimate, food and nesting resources), and dispersal. Canopy ant communities, including dominant and twig-nesting ants, are structured by all these different factors, but we know less about the impacts of species interactions and habitat filters acting at the colonization or recruitment stage. We examined occupation of artificial twig nests placed in shade trees in coffee agroecosystems. We asked whether species interactions-aggression from the dominant canopy ant, Azteca sericeasur Longino (Hymenoptera: Formicidae)-or habitat filtering-species of tree where nests were placed or surrounding vegetation-influence colonization, species richness, and community composition of twig-nesting ants. We found 20 species of ants occupying artificial nests. Nest occupation was lower on trees with A. sericeasur, but did not differ depending on tree species or surrounding vegetation. Yet, there were species-specific differences in occupation depending on A. sericeasur presence and tree species. Ant species richness did not vary with A. sericeasur presence or tree species. Community composition varied with A. sericeasur presence and surrounding vegetation. Our results suggest that species interactions with dominant ants are important determinants of colonization and community composition of twig-nesting ants. Habitat filtering at the level of tree species did not have strong effects on twig-nesting ants, but changes in coffee management may contribute to differences in community composition with important implications for ant conservation in agricultural landscapes, as well as biological control of coffee pests.

Food supplementation mitigates dispersal-dependent differences in nest defence in a passerine bird.

PubMed

Récapet, Charlotte; Daniel, Grégory; Taroni, Joëlle; Bize, Pierre; Doligez, Blandine

2016-05-01

Dispersing and non-dispersing individuals often differ in phenotypic traits (e.g. physiology, behaviour), but to what extent these differences are fixed or driven by external conditions remains elusive. We experimentally tested whether differences in nest-defence behaviour between dispersing and non-dispersing individuals changed with local habitat quality in collared flycatchers, by providing additional food during the nestling rearing period. In control (non-food-supplemented) nests, dispersers were less prone to defend their brood compared with non-dispersers, whereas in food-supplemented nests, dispersing and non-dispersing individuals showed equally strong nest defence. We discuss the importance of dispersal costs versus adaptive flexibility in reproductive investment in shaping these differences in nest-defence behaviour between dispersing and non-dispersing individuals. Irrespective of the underlying mechanisms, our study emphasizes the importance of accounting for environmental effects when comparing traits between dispersing and non-dispersing individuals, and in turn assessing the costs and benefits of dispersal. © 2016 The Author(s).

A new vertical grid nesting capability in the Weather Research and Forecasting (WRF) Model

DOE PAGES

Daniels, Megan H.; Lundquist, Katherine A.; Mirocha, Jeffrey D.; ...

2016-09-16

Mesoscale atmospheric models are increasingly used for high-resolution (<3 km) simulations to better resolve smaller-scale flow details. Increased resolution is achieved using mesh refinement via grid nesting, a procedure where multiple computational domains are integrated either concurrently or in series. A constraint in the concurrent nesting framework offered by the Weather Research and Forecasting (WRF) Model is that mesh refinement is restricted to the horizontal dimensions. This limitation prevents control of the grid aspect ratio, leading to numerical errors due to poor grid quality and preventing grid optimization. Here, a procedure permitting vertical nesting for one-way concurrent simulation is developedmore » and validated through idealized cases. The benefits of vertical nesting are demonstrated using both mesoscale and large-eddy simulations (LES). Mesoscale simulations of the Terrain-Induced Rotor Experiment (T-REX) show that vertical grid nesting can alleviate numerical errors due to large aspect ratios on coarse grids, while allowing for higher vertical resolution on fine grids. Furthermore, the coarsening of the parent domain does not result in a significant loss of accuracy on the nested domain. LES of neutral boundary layer flow shows that, by permitting optimal grid aspect ratios on both parent and nested domains, use of vertical nesting yields improved agreement with the theoretical logarithmic velocity profile on both domains. Lastly, vertical grid nesting in WRF opens the path forward for multiscale simulations, allowing more accurate simulations spanning a wider range of scales than previously possible.« less

A new vertical grid nesting capability in the Weather Research and Forecasting (WRF) Model

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

Daniels, Megan H.; Lundquist, Katherine A.; Mirocha, Jeffrey D.

Mesoscale atmospheric models are increasingly used for high-resolution (<3 km) simulations to better resolve smaller-scale flow details. Increased resolution is achieved using mesh refinement via grid nesting, a procedure where multiple computational domains are integrated either concurrently or in series. A constraint in the concurrent nesting framework offered by the Weather Research and Forecasting (WRF) Model is that mesh refinement is restricted to the horizontal dimensions. This limitation prevents control of the grid aspect ratio, leading to numerical errors due to poor grid quality and preventing grid optimization. Here, a procedure permitting vertical nesting for one-way concurrent simulation is developedmore » and validated through idealized cases. The benefits of vertical nesting are demonstrated using both mesoscale and large-eddy simulations (LES). Mesoscale simulations of the Terrain-Induced Rotor Experiment (T-REX) show that vertical grid nesting can alleviate numerical errors due to large aspect ratios on coarse grids, while allowing for higher vertical resolution on fine grids. Furthermore, the coarsening of the parent domain does not result in a significant loss of accuracy on the nested domain. LES of neutral boundary layer flow shows that, by permitting optimal grid aspect ratios on both parent and nested domains, use of vertical nesting yields improved agreement with the theoretical logarithmic velocity profile on both domains. Lastly, vertical grid nesting in WRF opens the path forward for multiscale simulations, allowing more accurate simulations spanning a wider range of scales than previously possible.« less

Excess atherosclerosis in systemic lupus erythematosus,—A matter of renal involvement: Case control study of 281 SLE patients and 281 individually matched population controls

PubMed Central

Gustafsson, Johanna T.; Herlitz Lindberg, Marie; Gunnarsson, Iva; Pettersson, Susanne; Elvin, Kerstin; Öhrvik, John; Larsson, Anders; Jensen-Urstad, Kerstin

2017-01-01

Background Systemic lupus erythematosus (SLE), is a heterogeneous disease which predominantly affects young females (90%). SLE is associated with a shorter life expectancy than in the general population. Standardized mortality ratios (SMR) of 2.4 have been reported, which is comparable to diabetes. In modern societies cardiovascular disease (CVD) is the major cause of premature mortality. Accelerated atherosclerosis is generally assumed to be the underlying cause for SLE related CVD. However, previous studies diverge regarding whether atherosclerosis is more common in SLE than in controls. With this in mind and based on own clinical experience we hypothesized that accelerated atherosclerosis is not a general feature of SLE, but prevails in SLE subgroups. Methods 281 SLE patients and 281 individually age and sex matched population controls, were investigated clinically. Fasting blood samples and risk factor data were collected. All participants were subject to B-mode ultrasonography of the carotid arteries. Carotid plaque occurrence and mean intima media thickness (mIMT) were recorded. Two SLE subgroups previously described to be at high CVD risk; 1) patients with nephritis and 2) patients with anti-phospholipid antibodies (aPL), and one subgroup reported to be at comparatively lower CVD risk; patients positive for Sjögren´s syndrome antigens A/B (SSA/SSB) antibodies were analyzed separately in comparison with their respective matched controls. Results Median age was 49 (IQR 36–59) years, 93% were females. Manifest CVD; ischemic heart, cerebro- and peripheral vascular disease, prevailed in patients (12% vs. 1%, p<0.0001). Overall plaque prevalence did not differ (20% vs. 16%), but patients had slightly higher mIMT than controls (0.56 vs. 0.53 mm, p<0.0033). After age adjustment plaques, but not mIMT, remained associated with previous CVD events. Therefore we focused further analyses on plaques, a more robust measure of atherosclerosis. Patients with nephritis (40%), but neither aPL (25%) nor SSA/SSB (40%) positive patients, had more plaques than their respective controls (23% vs. 11%, p = 0.008). Notably, patients with nephritis were younger than other SLE patients (45 vs.49 years, p = 0.02). To overcome the confounding effect of age we performed an age-matched nested case-control analysis, which demonstrated that patients with nephritis had twice as often plaques (23%) as both non-nephritis patients (11%, p = 0.038) and controls (12%, p = 0.035). Conclusions In SLE excess carotid plaques are essentially confined to the SLE subgroup with nephritis. This subgroup had plaques twice as often as age-matched non-nephritis SLE patients and population controls. Non-nephritis SLE patients, including the aPL positive subgroup, which has a high CVD risk, had similar prevalence of plaques as controls. To prevent later CVD events, this novel observation calls for risk factor screening and initiation of anti-atherosclerotic treatment selectively in SLE nephritis patients. Preferably at nephritis onset, which is often at a young age. In a general perspective this study demonstrates the importance to perform careful clinical subgroup analyses when investigating heterogeneous, hitherto not clearly defined, conditions like SLE. PMID:28414714

Great tits (Parus major) reduce caterpillar damage in commercial apple orchards.

PubMed

Mols, Christel M M; Visser, Marcel E

2007-02-07

Alternative ways to control caterpillar pests and reduce the use of pesticides in apple orchards are in the interest of the environment, farmers and the public. Great tits have already been shown to reduce damage under high caterpillar density when breeding in nest boxes in an experimental apple orchard. We tested whether this reduction also occurs under practical conditions of Integrated Pest Management (IPM), as well as Organic Farming (OF), by setting up an area with nest boxes while leaving a comparable area as a control within 12 commercial orchards. We showed that in IPM orchards, but not in OF orchards, in the areas with breeding great tits, apples had 50% of the caterpillar damage of the control areas. Offering nest boxes to attract insectivorous passerines in orchards can thus lead to more limited pesticide use, thereby adding to the natural biological diversity in an agricultural landscape, while also being economically profitable to the fruit growers.

Development of a rapid and sensitive one-step reverse transcription-nested polymerase chain reaction in a single tube using the droplet-polymerase chain reaction machine.

PubMed

Yamaguchi, Akemi; Matsuda, Kazuyuki; Sueki, Akane; Taira, Chiaki; Uehara, Masayuki; Saito, Yasunori; Honda, Takayuki

2015-08-25

Reverse transcription (RT)-nested polymerase chain reaction (PCR) is a time-consuming procedure because it has several handling steps and is associated with the risk of cross-contamination during each step. Therefore, a rapid and sensitive one-step RT-nested PCR was developed that could be performed in a single tube using a droplet-PCR machine. The K562 BCR-ABL mRNA-positive cell line as well as bone marrow aspirates from 5 patients with chronic myelogenous leukemia (CML) and 5 controls without CML were used. We evaluated one-step RT-nested PCR using the droplet-PCR machine. One-step RT-nested PCR performed in a single tube using the droplet-PCR machine enabled the detection of BCR-ABL mRNA within 40min, which was 10(3)-fold superior to conventional RT nested PCR using three steps in separate tubes. The sensitivity of the one-step RT-nested PCR was 0.001%, with sample reactivity comparable to that of the conventional assay. One-step RT-nested PCR was developed using the droplet-PCR machine, which enabled all reactions to be performed in a single tube accurately and rapidly and with high sensitivity. This one-step RT-nested PCR may be applicable to a wide spectrum of genetic tests in clinical laboratories. Copyright © 2015 Elsevier B.V. All rights reserved.

Nest ectoparasites increase physiological stress in breeding birds: an experiment.

PubMed

Martínez-de la Puente, Josué; Merino, Santiago; Tomás, Gustavo; Moreno, Juan; Morales, Judith; Lobato, Elisa; Martínez, Javier

2011-02-01

Parasites are undoubtedly a biotic factor that produces stress. Heat shock proteins (HSPs) are important molecules buffering cellular damage under adverse conditions. During the breeding season, blue tit Cyanistes caeruleus (L.) adults are affected by blood parasites, nest-dwelling parasites and biting flies, potentially affecting their HSP-mediated responses. Here, we treated females with primaquine to reduce blood parasites and fumigated nests with permethrin to reduce nest-dwelling parasites to test whether these treatments affect HSP60 level during the breeding season. Medicated females, but not controls, had a significant reduction of the intensity of infection by Haemoproteus spp. blood parasites. However, final intensity of infection did not differ significantly between groups, and we did not find an effect of medication on change in HSP60 level. Fumigation reduced the abundance of nest-dwelling parasites (mites, fleas and blowfly larvae) and engorged biting midges in nests. Females breeding in non-fumigated nests increased HSP60 levels during the season more than those breeding in fumigated nests. Furthermore, the change in HSP60 level was positively correlated with the abundance of biting midges. These results show how infections by nest ectoparasites during the breeding period can increase the level of HSPs and suggest that biting midges impose physiological costs on breeding female blue tits. Although plausible, the alternative that biting midges prefer to feed on more stressed birds is poorly supported by previous studies.

Effect of nesting environment on incubation temperature and hatching success of Morelet's crocodile (Crocodylus moreletii) in an urban lake of Southeastern Mexico.

PubMed

López-Luna, Marco A; Hidalgo-Mihart, Mircea G; Aguirre-León, Gustavo; González-Ramón, Mariana Del C; Rangel-Mendoza, Judith A

2015-01-01

Incubation temperature is an important aspect in terms of biological performance among crocodiles, and several controlled experiments have demonstrated a significant relationship between incubation temperature, success in hatching and survival of hatchlings. However, a few studies have tested these relationships in the wild. The objective of this study was to determine the relationship of nest characteristics and environment (hatch year, nest basal area and height, clutch size, distance to shore line, and vegetation cover), to incubation temperature and hatching success among Morelet's crocodile (Crocodylus moreletii). The study was carried out during the nesting seasons of Morelet's crocodile, from 2007 to 2009 in the Laguna de Las Ilusiones, an urban lake located in Villahermosa, Tabasco, Mexico. We physically characterized 18 nests and inserted a temperature data logger in each nest chamber. At the end of the nesting season and prior to hatching, we recovered the crocodile eggs and data loggers and calculated hatching success, under laboratory conditions. We related the environmental variables of the nest with the mean and fluctuation (standard deviation) of nest temperature, using linear models. We also related the environmental variables affecting the nest, to mean nest temperature and fluctuation in incubation temperature and to hatching success, using linear models. Although we found differences in incubation temperature between nests, mean incubation temperature did not differ between years, but there were differences in nest thermal fluctuation between years. The mean incubation temperature for 11 nests (61.1%) was lower than the suggested Female-Male pivotal temperature (producing 50% of each sex) for this species, and all hatchlings obtained were males. There were no differences in clutch size between years, but hatching success varied. Our study indicates that hatching success depends on certain environmental variables and nest conditions to which the eggs are subjected, including season, nest size and clutch size. We also discuss the importance of the fluctuation of incubation temperature on hatching success and sex determination. Copyright © 2015 Elsevier Ltd. All rights reserved.

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.

On a useful functional representation of control system structure

NASA Technical Reports Server (NTRS)

Malchow, Harvey L.

1988-01-01

An alternative structure for control systems is proposed. The structure is represented by a three-element block diagram and three functional definitions. It is argued that the three functional elements form a canonical set. The set includes the functions description, estimation and control. General overlay of the structure on parallel state and nested-state control systems is discussed. Breakdown of two real nested-state control systems into the proposed functional format is displayed. Application of the process to the mapping of complex control systems R and D efforts is explained with the Mars Rover Sample and Return mission as an example. A previous application of this basic functional structure to Space Station performance requirements organization is discussed.

Northern bobwhite breeding season ecology on a reclaimed surface mine

USGS Publications Warehouse

Brooke, Jarred M.; Tanner, Evan P.; Peters, David C.; Tanner, Ashley M.; Harper, Craig A.; Keyser, Patrick D.; Clark, Joseph D.; Morgan, John J.

2017-01-01

Surface coal mining and subsequent reclamation of surface mines have converted large forest areas into early successional vegetative communities in the eastern United States. This reclamation can provide a novel opportunity to conserve northern bobwhite (Colinus virginianus). We evaluated the influence of habitat management activities on nest survival, nest-site selection, and brood resource selection on managed and unmanaged units of a reclaimed surface mine, Peabody Wildlife Management Area (Peabody), in west-central Kentucky, USA, from 2010 to 2013. We compared resource selection, using discrete-choice analysis, and nest survival, using the nest survival model in Program MARK, between managed and unmanaged units of Peabody at 2 spatial scales: the composition and configuration of vegetation types (i.e., macrohabitat) and vegetation characteristics at nest sites and brood locations (i.e., microhabitat). On managed sites, we also investigated resource selection relative to a number of different treatments (e.g., herbicide, disking, prescribed fire). We found no evidence that nest-site selection was influenced by macrohabitat variables, but bobwhite selected nest sites in areas with greater litter depth than was available at random sites. On managed units, bobwhite were more likely to nest where herbicide was applied to reduce sericea lespedeza (Lespedeza cuneata) compared with areas untreated with herbicide. Daily nest survival was not influenced by habitat characteristics or by habitat management but was influenced by nest age and the interaction of nest initiation date and nest age. Daily nest survival was greater for older nests occurring early in the breeding season (0.99, SE < 0.01) but was lower for older nests occurring later in the season (0.08, SE = 0.13). Brood resource selection was not influenced by macrohabitat or microhabitat variables we measured, but broods on managed units selected areas treated with herbicide to control sericea lespedeza and were located closer to firebreaks and disked native-warm season grass stands than would be expected at random. Our results suggest the vegetation at Peabody was sufficient without manipulation to support nesting and brood-rearing northern bobwhite at a low level, but habitat management practices improved vegetation for nesting and brood-rearing resource selection. Reproductive rates (e.g., nest survival and re-nesting rates) at Peabody were lower than reported in other studies, which may be related to nutritional deficiencies caused by the abundance of sericea lespedeza. On reclaimed mine lands dominated by sericea lespedeza, we suggest continuing practices such as disking and herbicide application that are targeted at reducing sericea lespedeza to improve the vegetation for nesting and brood-rearing bobwhite.

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.

Should I stay or should I go? Hormonal control of nest abandonment in a long-lived bird, the Adélie penguin.

PubMed

Spée, Marion; Beaulieu, Michaël; Dervaux, Antoine; Chastel, Olivier; Le Maho, Yvon; Raclot, Thierry

2010-11-01

According to life-history theory, long-lived birds should favor their survival over the current reproductive attempt, when breeding becomes too costly. In seabirds, incubation is often associated with spontaneous long-term fasting. Below a threshold in body reserves, hormonal and metabolic shift characteristics of a switch from lipid to protein utilization (phase III, PIII) occur. These metabolic changes are paralleled by nest abandonment and stimulation of refeeding behavior. Parental behavior is then under control of two hormones with opposite effects: corticosterone (CORT) and prolactin which stimulate foraging and incubation behavior, respectively. The aim of this study was to determine the respective role of these two hormones in nest abandonment by Adélie penguins. To this end, plasma hormone levels were measured before egg-laying and at departure from the colony (i.e. when birds were relieved by their partner or abandoned their nest), and related to nutritional state and incubation success. We found that males abandoning their nest in PIII presented high CORT levels and low prolactin levels. Interestingly, males which presented high plasma levels of prolactin in PIII did not abandon. We show that although CORT is the first hormone to be affected by prolonged energy constraints, the combined effects of high CORT and low prolactin levels are necessary for parents to favor self-maintenance and abandon the nest. We provide insights into time-course changes of the endocrine profile as PIII proceeds and report that reaching proteolytic late fasting is not sufficient to induce nest abandonment in a long-lived bird. Copyright © 2010 Elsevier Inc. All rights reserved.

Food availability affects onset of reproduction in a long-lived seabird.

PubMed

Vincenzi, Simone; Hatch, Scott; Mangel, Marc; Kitaysky, Alexander

2013-06-07

Life-history theory predicts that suboptimal developmental conditions may lead to faster life histories (younger age at recruitment and higher reproductive investment), but experimental testing of this prediction is still scarce in long-lived species. We report the effects of an experimental manipulation of food availability during early development and at recruitment on the onset of reproduction and reproductive performance (productivity at first breeding) in a long-lived seabird, the black-legged kittiwake Rissa tridactyla, breeding on Middleton Island, Alaska. Birds were born and raised in nests with supplemented food ('fed') or unsupplemented control nests ('unfed'), and later recruited into either fed or unfed nests. Fed chicks grew faster than unfed chicks, and males grew faster than females. Birds were more likely to reproduce at younger ages when recruiting into fed nests. Faster growth during development tended to increase age at recruitment in all individuals. Social rank of individuals also affected age at recruitment: B-chicks recruited earlier than A-chicks and singletons recruited later than A- and B-chicks. Productivity increased with the age at recruitment and growth rate as chick, but much of the variability remained unexplained. We conclude that results of this study at least partially support predictions of life-history theory: younger age at first breeding for kittiwakes that experienced suboptimal natal conditions, as well as greater productivity of early recruiting kittiwakes that grew in control nests compared with those that grew in food-supplemented nests.

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.

Multilevel Analysis Methods for Partially Nested Cluster Randomized Trials

ERIC Educational Resources Information Center

Sanders, Elizabeth A.

2011-01-01

This paper explores multilevel modeling approaches for 2-group randomized experiments in which a treatment condition involving clusters of individuals is compared to a control condition involving only ungrouped individuals, otherwise known as partially nested cluster randomized designs (PNCRTs). Strategies for comparing groups from a PNCRT in the…

Parallel Treatments Design: A Nested Single Subject Design for Comparing Instructional Procedures.

ERIC Educational Resources Information Center

Gast, David L.; Wolery, Mark

1988-01-01

This paper describes the parallel treatments design, a nested single subject experimental design that combines two concurrently implemented multiple probe designs, allows control for effects of extraneous variables through counterbalancing, and replicates its effects across behaviors. Procedural guidelines for the design's use and issues related…

Acrylamide Hemoglobin Adduct Levels and Ovarian Cancer Risk: a nested case-control study

PubMed Central

Xie, Jing; Terry, Kathryn L.; Poole, Elizabeth M.; Wilson, Kathryn M.; Rosner, Bernard A.; Willett, Walter C.; Vesper, Hubert W.; Tworoger, Shelley S.

2013-01-01

Background Acrylamide is a probable human carcinogen formed during cooking of starchy foods. Two large prospective cohort studies of dietary acrylamide intake and ovarian cancer risk observed a positive association, although two other studies reported no association. Methods We measured acrylamide exposure using red blood cell acrylamide and glycidamide hemoglobin adducts among women in two large prospective cohorts: the Nurses’ Health Study and Nurses’ Health Study II. Between blood collection and 2010, we identified 263 incident cases of epithelial ovarian cancer, matching two controls per case. We used logistic regression models to examine the association between acrylamide exposure and ovarian cancer risk, adjusting for matching factors, family history of ovarian cancer, tubal ligation, oral contraceptive use, body mass index (BMI), parity, alcohol intake, smoking, physical activity, and caffeine intake. Results The multivariate-adjusted relative risk (RR) of ovarian cancer comparing the highest versus lowest tertile of total acrylamide adducts was 0.79 (95% CI: 0.50–1.24, P trend = 0.08). The comparable RR of ovarian cancer among non-smokers at blood draw was 0.85 (95% CI: 0.57–1.27, P trend =0.14). The association did not differ by tumor histology (serous invasive versus not), P for heterogeneity=0.41. Individual adduct types (acrylamide or glycidamide) were not associated with risk. Conclusions We observed no evidence that acrylamide exposure as measured by adducts to hemoglobin is associated with an increased risk of ovarian cancer. Impact Our finding indicates that acrylamide intake may not increase risk of ovarian cancer. PMID:23417989

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.

Phase transition of Boolean networks with partially nested canalizing functions

NASA Astrophysics Data System (ADS)

Jansen, Kayse; Matache, Mihaela Teodora

2013-07-01

We generate the critical condition for the phase transition of a Boolean network governed by partially nested canalizing functions for which a fraction of the inputs are canalizing, while the remaining non-canalizing inputs obey a complementary threshold Boolean function. Past studies have considered the stability of fully or partially nested canalizing functions paired with random choices of the complementary function. In some of those studies conflicting results were found with regard to the presence of chaotic behavior. Moreover, those studies focus mostly on ergodic networks in which initial states are assumed equally likely. We relax that assumption and find the critical condition for the sensitivity of the network under a non-ergodic scenario. We use the proposed mathematical model to determine parameter values for which phase transitions from order to chaos occur. We generate Derrida plots to show that the mathematical model matches the actual network dynamics. The phase transition diagrams indicate that both order and chaos can occur, and that certain parameters induce a larger range of values leading to order versus chaos. The edge-of-chaos curves are identified analytically and numerically. It is shown that the depth of canalization does not cause major dynamical changes once certain thresholds are reached; these thresholds are fairly small in comparison to the connectivity of the nodes.

Effects of Fungicide and Adjuvant Sprays on Nesting Behavior in Two Managed Solitary Bees, Osmia lignaria and Megachile rotundata

PubMed Central

2015-01-01

There is a growing body of empirical evidence showing that wild and managed bees are negatively impacted by various pesticides that are applied in agroecosystems around the world. The lethal and sublethal effects of two widely used fungicides and one adjuvant were assessed in cage studies in California on blue orchard bees, Osmia lignaria, and in cage studies in Utah on alfalfa leafcutting bees, Megachile rotundata. The fungicides tested were Rovral 4F (iprodione) and Pristine (mixture of pyraclostrobin + boscalid), and the adjuvant tested was N-90, a non-ionic wetting agent (90% polyethoxylated nonylphenol) added to certain tank mixtures of fungicides to improve the distribution and contact of sprays to plants. In separate trials, we erected screened cages and released 20 paint-marked females plus 30–50 males per cage to document the behavior of nesting bees under treated and control conditions. For all females in each cage, we recorded pollen-collecting trip times, nest substrate-collecting trip times (i.e., mud for O. lignaria and cut leaf pieces for M. rotundata), cell production rate, and the number of attempts each female made to enter her own or to enter other nest entrances upon returning from a foraging trip. No lethal effects of treatments were observed on adults, nor were there effects on time spent foraging for pollen and nest substrates and on cell production rate. However, Rovral 4F, Pristine, and N-90 disrupted the nest recognition abilities of O. lignaria females. Pristine, N-90, and Pristine + N-90 disrupted nest recognition ability of M. rotundata females. Electroantennogram responses of antennae of O. lignaria females maintained in the laboratory did not differ significantly between the fungicide-exposed and control bees. Our results provide the first empirical evidence that two commonly used fungicides and a non-ionic adjuvant can disrupt nest recognition in two managed solitary bee species. PMID:26274401

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.

Nest site selection by Kentish plover suggests a trade-off between nest-crypsis and predator detection strategies.

PubMed

Gómez-Serrano, Miguel Ángel; López-López, Pascual

2014-01-01

Predation is one of the main causes of adult mortality and breeding failure for ground-nesting birds. Micro-habitat structure around nests plays a critical role in minimizing predation risk. Plovers nest in sites with little vegetation cover to maximize the incubating adult visibility, but many studies suggest a trade-off between nest-crypsis and predator detection strategies. However, this trade-off has not been explored in detail because methods used so far do not allow estimating the visibility with regards to critical factors such as slope or plant permeability to vision. Here, we tested the hypothesis that Kentish plovers select exposed sites according to a predator detection strategy, and the hypothesis that more concealed nests survive longer according to a crypsis strategy. To this end, we obtained an accurate estimation of the incubating adult's field of vision through a custom built inverted periscope. Our results showed that plovers selected nest sites with higher visibility than control points randomly selected with regards to humans and dogs, although nests located in sites with higher vegetation cover survived longer. In addition, the flushing distance (i.e., the distance at which incubating adults leave the nest when they detect a potential predator) decreased with vegetation cover. Consequently, the advantages of concealing the nest were limited by the ability to detect predators, thus indirectly supporting the existence of the trade-off between crypsis and predator detection. Finally, human disturbance also constrained nest choice, forcing plovers to move to inland sites that were less suitable because of higher vegetation cover, and modulated flushing behavior, since plovers that were habituated to humans left their nests closer to potential predators. This constraint on the width of suitable breeding habitat is particularly relevant for the conservation of Kentish Plover in sand beaches, especially under the current context of coastal regression and increase of recreational activities.

Nest Site Selection by Kentish Plover Suggests a Trade-Off between Nest-Crypsis and Predator Detection Strategies

PubMed Central

Gómez-Serrano, Miguel Ángel; López-López, Pascual

2014-01-01

Predation is one of the main causes of adult mortality and breeding failure for ground-nesting birds. Micro-habitat structure around nests plays a critical role in minimizing predation risk. Plovers nest in sites with little vegetation cover to maximize the incubating adult visibility, but many studies suggest a trade-off between nest-crypsis and predator detection strategies. However, this trade-off has not been explored in detail because methods used so far do not allow estimating the visibility with regards to critical factors such as slope or plant permeability to vision. Here, we tested the hypothesis that Kentish plovers select exposed sites according to a predator detection strategy, and the hypothesis that more concealed nests survive longer according to a crypsis strategy. To this end, we obtained an accurate estimation of the incubating adult's field of vision through a custom built inverted periscope. Our results showed that plovers selected nest sites with higher visibility than control points randomly selected with regards to humans and dogs, although nests located in sites with higher vegetation cover survived longer. In addition, the flushing distance (i.e., the distance at which incubating adults leave the nest when they detect a potential predator) decreased with vegetation cover. Consequently, the advantages of concealing the nest were limited by the ability to detect predators, thus indirectly supporting the existence of the trade-off between crypsis and predator detection. Finally, human disturbance also constrained nest choice, forcing plovers to move to inland sites that were less suitable because of higher vegetation cover, and modulated flushing behavior, since plovers that were habituated to humans left their nests closer to potential predators. This constraint on the width of suitable breeding habitat is particularly relevant for the conservation of Kentish Plover in sand beaches, especially under the current context of coastal regression and increase of recreational activities. PMID:25208045

Nest survival of forest birds in the Mississippi Alluvial Valley

USGS Publications Warehouse

Twedt, D.J.; Wilson, R.R.; Henne-Kerr, J.L.; Hamilton, R.B.

2001-01-01

In the Mississippi Alluvial Valley, flood control has led to a drastic reduction in the area of forest habitat and altered the patchwork of forest cover types. Silvicultural management of the remaining fragmented forests has changed to reflect the altered hydrology of the forests, current economic conditions of the area, and demand for forest products. Because forest type and silvicultural management impact forest birds, differences in avian productivity within these forests directly impact bird conservation. To assist in conservation planning, we evaluated daily nest survival, nest predation rates, and brood parasitism rates of forest birds in relation to different forest cover types and silvicultural management strategies within this floodplain. Within bottomland hardwood forests, nest success of blue-gray gnatcatcher (Polioptila caerulea, 13%), eastern towhee (Pipilo erythrophthalmus, 28%), indigo bunting (Passerina cyanea, 18%), northern cardinal (Cardinalis cardinalis, 22%), and yellow-billed cuckoo (Coccyzus americanus, 18%) did not differ from that within intensively managed cottonwood plantations. However, average daily survival of 542 open-cup nests of 19 bird species in bottomland hardwoods (0.9516 + 0.0028, -27% nest success) was greater than that of 543 nests of 18 species in cotlonwood plantations (0.9298 + 0.0035, -15% nest success). Differences in daily nest survival rates likely resulted from a combination of differences in the predator community--particularly fire ants (Solenopsis invicta)--and a marked difference in species composition of birds breeding within these 2 forest types. At least 39% of nests in bottomland hardwood forests and 65% of nests in cottonwood plantations were depredated. Rates of parasitism by brown-headed cowbirds (Molothrus ater) were greater in managed cottonwoods (24%) than in bottomland hardwoods (9%). Nest success in planted cottonwood plantations for 18 species combined (-14%), and for yellow-breasted chat (Icteria vimns, 7%), eastern towhee (14%), indigo bunting (14%), and northern cardinal (17%) did not differ from nest success in cottonwood plantations that were coppiced from root sprouts following pulpwood harvest. Within bottomland hardwood forests, uneven-aged group-selection timber harvest reduced the combined daily nest survival of all species from 0.958 to 0.938, which reduced nest success by about 14%. Specifically, timber harvest reduced nest success of species that nest in the forest midstory and canopy, such as Acadian flycatcher (Empidonax virescens)--from 32% before harvest to 14% after harvest. Conversely, those species that nest primarily in the shrubby understory--such as northern cardinal--were not affected by timber harvest and maintained an overall nest success of about 33%. Thus, birds nesting in the understory of bottomland hardwood forests are not adversely impacted by selective timber harvest, but there is a short-term reduction in nest success for birds that nest in the canopy and midstory.

Metabolic heating and the prediction of sex ratios for green turtles (Chelonia mydas).

PubMed

Broderick, A C; Godley, B J; Hays, G C

2001-01-01

We compared incubation temperatures in nests (n=32) of the green turtle (Chelonia mydas) on Ascension Island in relation to sand temperatures of control sites at nest depth. Intrabeach thermal variation was low, whereas interbeach thermal variation was high in both control and nest sites. A marked rise in temperature was recorded in nests from 30% to 40% of the way through the incubation period and attributed to metabolic heating. Over the entire incubation period, metabolic heating accounted for a mean rise in temperature of between 0.07 degrees and 2.86 degrees C within nests. During the middle third of incubation, when sex is thought to be determined, this rise in temperature ranged between 0.07 degrees and 2.61 degrees C. Metabolic heating was related to both the number of eggs laid and the total number of hatchlings/embryos produced in a clutch. For 32 clutches in which temperature was recorded, we estimate that metabolic heating accounted for a rise of up to 30% in the proportion of females produced within different clutches. Previous studies have dismissed any effect of metabolic heating on the sex ratio of marine turtle hatchlings. Our results imply that metabolic heating needs to be considered when estimating green turtle hatchling sex ratios.

Leafcutter bee nests and pupae from the Rancho La Brea Tar Pits of Southern California: implications for understanding the paleoenvironment of the Late Pleistocene.

PubMed

Holden, Anna R; Koch, Jonathan B; Griswold, Terry; Erwin, Diane M; Hall, Justin

2014-01-01

The Rancho La Brea Tar Pits is the world's richest and most important Late Pleistocene fossil locality and best renowned for numerous fossil mammals and birds excavated over the past century. Less researched are insects, even though these specimens frequently serve as the most valuable paleoenvironemental indicators due to their narrow climate restrictions and life cycles. Our goal was to examine fossil material that included insect-plant associations, and thus an even higher potential for significant paleoenviromental data. Micro-CT scans of two exceptionally preserved leafcutter bee nest cells from the Rancho La Brea Tar Pits in Los Angeles, California reveal intact pupae dated between ∼23,000-40,000 radiocarbon years BP. Here identified as best matched to Megachile (Litomegachile) gentilis Cresson (Hymenoptera: Megachilidae) based on environmental niche models as well as morphometrics, the nest cells (LACMRLP 388E) document rare preservation and life-stage. The result of complex plant-insect interactions, they offer new insights into the environment of the Late Pleistocene in southern California. The remarkable preservation of the nest cells suggests they were assembled and nested in the ground where they were excavated. The four different types of dicotyledonous leaves used to construct the cells were likely collected in close proximity to the nest and infer a wooded or riparian habitat with sufficient pollen sources for larval provisions. LACMRLP 388E is the first record of fossil Megachile Latreille cells with pupae. Consequently, it provides a pre-modern age location for a Nearctic group, whose phylogenetic relationships and biogeographic history remain poorly understood. Megachile gentilis appears to respond to climate change as it has expanded its distribution across elevation gradients over time as estimated by habitat suitability comparisons between low and high elevations; it currently inhabits mesic habitats which occurred at a lower elevation during the Last Glacial Maximum ∼21,000 years ago. Nevertheless, the broad ecological niche of M. gentilis appears to have remained stable.

Leafcutter Bee Nests and Pupae from the Rancho La Brea Tar Pits of Southern California: Implications for Understanding the Paleoenvironment of the Late Pleistocene

PubMed Central

Holden, Anna R.; Koch, Jonathan B.; Griswold, Terry; Erwin, Diane M.; Hall, Justin

2014-01-01

The Rancho La Brea Tar Pits is the world’s richest and most important Late Pleistocene fossil locality and best renowned for numerous fossil mammals and birds excavated over the past century. Less researched are insects, even though these specimens frequently serve as the most valuable paleoenvironemental indicators due to their narrow climate restrictions and life cycles. Our goal was to examine fossil material that included insect-plant associations, and thus an even higher potential for significant paleoenviromental data. Micro-CT scans of two exceptionally preserved leafcutter bee nest cells from the Rancho La Brea Tar Pits in Los Angeles, California reveal intact pupae dated between ∼23,000–40,000 radiocarbon years BP. Here identified as best matched to Megachile (Litomegachile) gentilis Cresson (Hymenoptera: Megachilidae) based on environmental niche models as well as morphometrics, the nest cells (LACMRLP 388E) document rare preservation and life-stage. The result of complex plant-insect interactions, they offer new insights into the environment of the Late Pleistocene in southern California. The remarkable preservation of the nest cells suggests they were assembled and nested in the ground where they were excavated. The four different types of dicotyledonous leaves used to construct the cells were likely collected in close proximity to the nest and infer a wooded or riparian habitat with sufficient pollen sources for larval provisions. LACMRLP 388E is the first record of fossil Megachile Latreille cells with pupae. Consequently, it provides a pre-modern age location for a Nearctic group, whose phylogenetic relationships and biogeographic history remain poorly understood. Megachile gentilis appears to respond to climate change as it has expanded its distribution across elevation gradients over time as estimated by habitat suitability comparisons between low and high elevations; it currently inhabits mesic habitats which occurred at a lower elevation during the Last Glacial Maximum ∼21,000 years ago. Nevertheless, the broad ecological niche of M. gentilis appears to have remained stable. PMID:24718701

Resource distributions among habitats determine solitary bee offspring production in a mosaic landscape.

PubMed

Williams, Neal M; Kremen, Claire

2007-04-01

Within mosaic landscapes, many organisms depend on attributes of the environment that operate over scales ranging from a single habitat patch to the entire landscape. One such attribute is resource distribution. Organisms' reliance on resources from within a local patch vs. those found among habitats throughout the landscape will depend on local habitat quality, patch quality, and landscape composition. The ability of individuals to move among complementary habitat types to obtain various resources may be a critical mechanism underlying the dynamics of animal populations and ultimately the level of biodiversity at different spatial scales. We examined the effects that local habitat type and landscape composition had on offspring production and survival of the solitary bee Osmia lignaria in an agri-natural landscape in California (U.S.A.). Female bees were placed on farms that did not use pesticides (organic farms), on farms that did use pesticides (conventional farms), or in seminatural riparian habitats. We identified pollens collected by bees nesting in different habitat types and matched these to pollens of flowering plants from throughout the landscape. These data enabled us to determine the importance of different plant species and habitat types in providing food for offspring, and how this importance changed with landscape and local nesting-site characteristics. We found that increasing isolation from natural habitat significantly decreased offspring production and survival for bees nesting at conventional farms, had weaker effects on bees in patches of seminatural habitat, and had little impact on those at organic farm sites. Pollen sampled from nests showed that females nesting in both farm and seminatural habitats relied on pollen from principally native plant species growing in seminatural habitat. Thus connectivity among habitats was critical for offspring production. Females nesting on organic farms were buffered to isolation effects by switching to floral resources growing at the farm site when seminatural areas were too distant. Overall local habitat conditions (farm management practices) can help bolster pollinators, but maintaining functional connectivity among habitats will likely be critical for persistence of pollinator populations as natural habitats are increasingly fragmented by human activities.

Parathion alters incubation behavior of laughing gulls

USGS Publications Warehouse

White, D.H.; Mitchell, C.A.; Hill, E.F.

1983-01-01

One member of each pair of incubating laughing gulls at 9 nests was trapped, orally dosed with either 6 mg/kg parathion in corn oil or corn oil alone, and marked about the neck with red dye. Each nest was marked with a numbered stake and the treatment was recorded. A pilot study with captive laughing gulls had determined the proper dosage of parathion that would significantly inhibit their brain AChE activity (about 50% of normal) without overt signs of poisoning. After dosing, birds were released and the nests were observed for 2 1/2 days from a blind on the nesting island. The activities of the birds at each marked nest were recorded at 10-minute intervals. Results indicated that on the day of treatment there was no difference (P greater than 0.05, Chi-square test) in the proportion of time spent on the nest between treated and control birds. However, birds dosed with 6 mg/kg parathion spent significantly less time incubating on days 2 and 3 than did birds receiving only corn oil. By noon on the third day, sharing of nest duties between pair members in the treated group had approached normal, indicating recovery from parathion intoxication. These findings suggest that sublethal exposure of nesting birds to an organophosphate (OP) insecticide, such as parathion, may result in decreased nest attentiveness, thereby making the clutch more susceptible to predation or egg failure. Behavioral changes caused by sublethal OP exposure could be especially detrimental in avian species where only one pair member incubates or where both members are exposed in species sharing nest duties.

No Compromise of Competition Sleep Compared With Habitual Sleep in Elite Australian Footballers.

PubMed

Lalor, Benita J; Halson, Shona L; Tran, Jacqueline; Kemp, Justin G; Cormack, Stuart J

2018-01-01

To assess the impact of match-start time and days relative to match compared with the habitual sleep characteristics of elite Australian Football (AF) players. 45 elite male AF players were assessed during the preseason (habitual) and across 4 home matches during the season. Players wore an activity monitor the night before (-1), night of (0), 1 night after (+1), and 2 nights (+2) after each match and completed a self-reported rating of sleep quality. A 2-way ANOVA with Tukey post hoc was used to determine differences in sleep characteristics between match-start times and days relative to the match. Two-way nested ANOVA was conducted to examine differences between competition and habitual phases. Effect size ± 90% confidence interval (ES ± 90% CI) was calculated to quantify the magnitude of pairwise differences. Differences observed in sleep-onset latency (ES = 0.11 ± 0.16), sleep rating (ES = 0.08 ± 0.14), and sleep duration (ES = 0.08 ± 0.01) between competition and habitual periods were trivial. Sleep efficiency was almost certainly higher during competition than habitual, but this was not reflected in the subjective rating of sleep quality. Elite AF competition does not cause substantial disruption to sleep characteristics compared with habitual sleep. While match-start time has some impact on sleep variables, it appears that the match itself is more of a disruption than the start time. Subjective ratings of sleep from well-being questionnaires appear limited in their ability to accurately provide an indication of sleep quality.

Effects of acute alcohol withdrawal on nest building in mice selectively bred for alcohol withdrawal severity

PubMed Central

Greenberg, Gian D.; Phillips, Tamara J.; Crabbe, John C.

2017-01-01

Nest building has been used to assess thermoregulatory behavior and positive motivational states in mice. There are known genetic influences on ethanol withdrawal severity as well as individual/thermoregulatory nest building. Withdrawal Seizure-Prone (WSP-1, WSP-2) and Withdrawal Seizure-Resistant (WSR-1, WSR-2) mice were selectively bred for high vs low handling-induced convulsion (HIC) severity, respectively, during withdrawal from chronic ethanol vapor inhalation. They also differ in HIC severity during withdrawal from an acute, 4 g/kg ethanol injection. In our initial study, withdrawal from an acute dose of ethanol dose-dependently impaired nest building over the initial 24 h of withdrawal in genetically segregating Withdrawal Seizure Control (WSC) mice. In two further studies, acute ethanol withdrawal suppressed nest building for up to two days in WSP-1 females. Deficits in nest building from ethanol were limited to the initial 10 h of withdrawal in WSR-1 females and to the initial 24 h of withdrawal in WSP-1 and WSR-1 males. Effects of ethanol on nest building for up to two days were found in WSP-2 and WSR-2 mice of both sexes. Nest building deficits in female mice from the first replicate could not be explained by a general decrease in locomotor behavior. These results suggest that nest building is a novel behavioral phenotype for indexing the severity of acute ethanol withdrawal, and that genes contributing to this trait differ from those affecting acute withdrawal HIC severity. PMID:27503811

Hydrological responses in water loss due to thinning of forested watersheds in Japan using the short-term water balance method

NASA Astrophysics Data System (ADS)

Sano, K.; Gomi, T.; Hiraoka, M.; Sato, T.; Onda, Y.

2015-12-01

We examined the changes in seasonal patterns of catchment-scale evapotranspiration (i.e., water loss) using Short-Term Water Balance Model (STWBM) developed. STWBM is applied to estimate the value of water loss based on precipitation minus discharge volume during　short-periods(8 to 80 days). This method can be applicable for examining seasonal characteristics of water loss that relets to ET. We applied STWBM for investigating the effects of 50% thinning in nested headwater catchments draining Japanese cypress (Cryptomeria japonica) and cedar (Chamaecyparis obtusa) forests. Study areas is located to 70 km north of Tokyo with 1250 mm annual precipitation and 14℃ mean annual temperature. 50% of the stems (46% of timber volume) were removed by strip thinning in 17 ha treatment catchment, 9 ha catchment remained untreated as a control. We installed 4 nested gauging stations in treated and control catchments with 3 to 10 ha of drainage areas. Runoff in each nested gauging station was measured in the pre- (from April, 2010 to June 2011) and the post-thinning periods (from January 2012 to December 2012). Total runoff coefficient in treated and control catchment was 54% and 26%, respectively. , . Estimated annual water loss by STWBM was 585 mm in treated and 969 mm in control catchments. Because annual evapotranspiration of Japanese cypress and cedar was about ranging from 400 to 800 mm in this catchment, our estimated water loss mostly associated with ET and partially by water loss by deep bedrock percolation. Estimated water loss after thinning in growth season (May to October) decreased 45 to 60 (in 2012) % and 51 to 60 (in 2013) % for all nested gauging station, while estimated water loss in control catchment was consistent. This result suggested that 50% of thinning decreased water loss by ET but changes can be varied among nested gauging station.

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

Avian growth and development rates and age-specific mortality: the roles of nest predation and adult mortality.

PubMed

Remes, V

2007-01-01

Previous studies have shown that avian growth and development covary with juvenile mortality. Juveniles of birds under strong nest predation pressure grow rapidly, have short incubation and nestling periods, and leave the nest at low body mass. Life-history theory predicts that parental investment increases with adult mortality rate. Thus, developmental traits that depend on the parental effort exerted (pre- and postnatal growth rate) should scale positively with adult mortality, in contrast to those that do not have a direct relationship with parental investment (timing of developmental events, e.g. nest leaving). I tested this prediction on a sample of 84 North American songbirds. Nestling growth rate scaled positively and incubation period duration negatively with annual adult mortality rates even when controlled for nest predation and other covariates, including phylogeny. On the contrary, neither the duration of the nestling period nor body mass at fledging showed any relationship. Proximate mechanisms generating the relationship of pre- and postnatal growth rates to adult mortality may include increased feeding, nest attentiveness during incubation and/or allocation of hormones, and deserve further attention.

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

Breeding Sex Ratios in Adult Leatherback Turtles (Dermochelys coriacea) May Compensate for Female-Biased Hatchling Sex Ratios

PubMed Central

Stewart, Kelly R.; Dutton, Peter H.

2014-01-01

For vertebrates with temperature-dependent sex determination, primary (or hatchling) sex ratios are often skewed, an issue of particular relevance to concerns over effects of climate change on populations. However, the ratio of breeding males to females, or the operational sex ratio (OSR), is important to understand because it has consequences for population demographics and determines the capacity of a species to persist. The OSR also affects mating behaviors and mate choice, depending on the more abundant sex. For sea turtles, hatchling and juvenile sex ratios are generally female-biased, and with warming nesting beach temperatures, there is concern that populations may become feminized. Our purpose was to evaluate the breeding sex ratio for leatherback turtles at a nesting beach in St. Croix, USVI. In 2010, we sampled nesting females and later sampled their hatchlings as they emerged from nests. Total genomic DNA was extracted and all individuals were genotyped using 6 polymorphic microsatellite markers. We genotyped 662 hatchlings from 58 females, matching 55 females conclusively to their nests. Of the 55, 42 females mated with one male each, 9 mated with 2 males each and 4 mated with at least 3 males each, for a multiple paternity rate of 23.6%. Using GERUD1.0, we reconstructed parental genotypes, identifying 47 different males and 46 females for an estimated breeding sex ratio of 1.02 males for every female. Thus we demonstrate that there are as many actively breeding males as females in this population. Concerns about female-biased adult sex ratios may be premature, and mate choice or competition may play more of a role in sea turtle reproduction than previously thought. We recommend monitoring breeding sex ratios in the future to allow the integration of this demographic parameter in population models. PMID:24505403

Life history and environmental requirements of loggerhead turtles

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

Nelson, D.A.

1988-08-01

In the United States scattered nestings of loggerhead sea turtles (Caretta caretta) may occur in most of its range from Texas to Florida and Florida to New Jersey; however, nesting concentrations occur on coastal islands of North Carolina, South Carolina, and Georgia and on the coasts of Florida. The greatest portion of a loggerhead's life is spent in ocean and estuarine waters where it breeds in shallow waters adjacent to nesting beaches, feeds on a variety of fish and shellfish, and migrates generally north in the spring and summer and south in the fall and winter. The other part ofmore » its life is spent on coastal beaches where the female digs a nest, lays her eggs (average 120 eggs), the eggs hatch (in 46 to 65 days), and the hatchlings emerge from the nest as a group and orient seaward to become part of the aquatic system again. Nesting activity begins in the spring, peaks in midsummer, and declines until completion in late summer. A loggerhead female generally nests every other or every third year. Beach sand temperatures may affect nest site selection by females, the incubation time and hatching success of eggs, and the sex and emergence timing of hatchlings. Most management of sea turtles has been directed toward increasing hatching and hatchling success through predator control, egg relocation, and raising captive hatchlings. 183 refs.; 10 figs.; 3 tabs.« less

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.

Use of nested PCR to detect Ceratocystis fagacearum in sapwood of diseased northern oak species

USDA-ARS?s Scientific Manuscript database

Early and accurate diagnosis of oak wilt, caused by Ceratocystis fagacearum (Cf), is important when disease control action is planned. When laboratory diagnosis is needed, standard isolation protocols that are used rely on high quality samples and require > 14 days for incubation. Use of a nested P...

Predation by ants controls swallow bug (Hemiptera: Cimicidae: Oeciacus vicarius) infestations.

PubMed

Brown, Charles R; Page, Catherine E; Robison, Grant A; O'Brien, Valerie A; Booth, Warren

2015-06-01

The swallow bug (Oeciacus vicarius) is the only known vector for Buggy Creek virus (BCRV), an alphavirus that circulates in cliff swallows (Petrochelidon pyrrhonota) and house sparrows (Passer domesticus) in North America. We discovered ants (Crematogaster lineolata and Formica spp.) preying on swallow bugs at cliff swallow colonies in western Nebraska, U.S.A. Ants reduced the numbers of visible bugs on active swallow nests by 74-90%, relative to nests in the same colony without ants. Ant predation on bugs had no effect on the reproductive success of cliff swallows inhabiting the nests where ants foraged. Ants represent an effective and presumably benign way of controlling swallow bugs at nests in some colonies. They may constitute an alternative to insecticide use at sites where ecologists wish to remove the effects of swallow bugs on cliff swallows or house sparrows. By reducing bug numbers, ant presence may also lessen BCRV transmission at the spatial foci (bird colony sites) where epizootics occur. The effect of ants on swallow bugs should be accounted for in studying variation among sites in vector abundance. © 2015 The Society for Vector Ecology.

The role of egg-nest contrast in the rejection of brood parasitic eggs.

PubMed

Aidala, Zachary; Croston, Rebecca; Schwartz, Jessica; Tong, Lainga; Hauber, Mark E

2015-04-15

Hosts of avian brood parasites can avoid the reproductive costs of raising genetically unrelated offspring by rejecting parasitic eggs. The perceptual cues and controls mediating parasitic egg discrimination and ejection are well studied: hosts are thought to use differences in egg color, brightness, maculation, size and shape to discriminate between their own and foreign eggs. Most theories of brood parasitism implicitly assume that the primary criteria to which hosts attend when discriminating eggs are differences between the eggs themselves. However, this assumption is confounded by the degree to which chromatic and achromatic characteristics of the nest lining co-vary with egg coloration, so that egg-nest contrast per se might be the recognition cue driving parasitic egg detection. Here, we systematically tested whether and how egg-nest contrast itself contributes to foreign egg discrimination. In an artificial parasitism experiment, we independently manipulated egg color and nest lining color of the egg-ejector American robin (Turdus migratorius), a host of the obligate brood parasitic brown-headed cowbird (Molothrus ater). We hypothesized that the degree of contrast between foreign eggs and the nest background would affect host egg rejection behavior. We predicted that experimentally decreasing egg-nest chromatic and achromatic contrast (i.e. rendering parasitic eggs more cryptic against the nest lining) would decrease rejection rates, while increasing egg-nest contrast would increase rejection rates. In contrast to our predictions, egg-nest contrast was not a significant predictor of egg ejection patterns. Instead, egg color significantly predicted responses to parasitism. We conclude that egg-egg differences are the primary drivers of egg rejection in this system. Future studies should test for the effects of egg-nest contrast per se in predicting parasitic egg recognition in other host-parasite systems, including those hosts building enclosed nests and those parasites laying cryptic eggs, as an alternative to hypothesized effects of egg-egg contrast. © 2015. Published by The Company of Biologists Ltd.

Evolution of sexual dichromatism in relation to nesting habits in European passerines: a test of Wallace's hypothesis.

PubMed

Soler, J J; Moreno, J

2012-08-01

Wallace proposed in 1868 that natural rather than sexual selection could explain the striking differences in avian plumage dichromatism. Thus, he predicted that nesting habits, through their association with nest predation, could drive changes in sexual dichromatism by enabling females in cavity nesters to become as conspicuous as males, whereas Darwin (1871, The Descent of Man and Selection in Relation to Sex, John Murray, London) argued that sexual selection was the sole explanation for dichromatism. Sexual dichromatism is currently used as indicating the strength of sexual selection, and therefore testing Wallace's claim with modern phylogentically controlled methodologies is of prime interest for comparing the roles of natural and sexual selection in affecting the evolution of avian coloration. Here, we have related information on nest attendance, sexual dichromatism and nesting habits (open and cavity nesting) to male and female plumage conspicuousness in European passerines. Nest incubation attendance does not explain male or female plumage conspicuousness but nest type does. Moreover, although females of monochromatic and cavity nesting species are more conspicuous than females of other species, males of monochromatic and open nesting species are those with more cryptic plumage. Finally, analyses of character evolution suggest that changes in nesting habits influence the probability of changes in both dichromatism and plumage conspicuousness of males but do not significantly affect those in females. These results strongly suggest a role of nesting habits in the evolution of plumage conspicuousness of males, and a role for sexual selection also in females, both factors affecting the evolution of sexual dichromatism. We discuss our findings in relation to the debate that Darwin and Wallace maintained more than one century ago on the importance of natural and sexual selection in driving the evolution of plumage conspicuousness and sexual dichromatism in birds, and conclude that our results partly support the evolutionary scenarios envisaged by both extraordinary scientists. © 2012 The Authors. Journal of Evolutionary Biology © 2012 European Society For Evolutionary Biology.

Evaluation of ERTS multispectral signatures in relation to ground control signatures using a nested-sampling approach

NASA Technical Reports Server (NTRS)

Lyon, R. J. P. (Principal Investigator)

1975-01-01

The author has identified the following significant results. Ground measured spectral signatures of wavelength bands matching ERTS MSS were collected using a radiometer at several Californian and Nevadan sites, and directly compared with similar data from ERTS CCTs. The comparison was tested at the highest possible spatial resolution for ERTS, using deconvoluted MSS data, and contrasted with that of ground measured spectra, originally from 1 meter squares. In the mobile traverses of the grassland sites, these one meter fields of view were integrated into eighty meter transects along the five km track across four major rock/soil types. Suitable software was developed to read the MSS CCT tapes, to shadeprint individual bands with user-determined greyscale stretching. Four new algorithms for unsupervised and supervised, normalized and unnormalized clustering were developed, into a program termed STANSORT. Parallel software allowed the field data to be calibrated, and by using concurrently continuously collected, upward- and downward-viewing, 4 band radiometers, bidirectional reflectances could be calculated.

Uric acid and serum antioxidant capacity: a reaction to atherosclerosis?

PubMed

Nieto, F J; Iribarren, C; Gross, M D; Comstock, G W; Cutler, R G

2000-01-01

the evidence of a potential beneficial role of antioxidants in preventing atherosclerotic disease is not entirely consistent. to assess the longitudinal association of serum total antioxidant capacity and serum antioxidants with the presence of subclinical carotid atherosclerosis. Prospective case-control study nested within an historical cohort. Cases were 150 individuals with elevated carotid intimal-medial thickness measured by B-mode ultrasound at the first two examinations of the Atherosclerosis Risk in Communities Study (1987-92). Controls were 150 age-gender-matched individuals with low carotid intimal-medial thickness. Serum antioxidant vitamins, uric acid, and serum total antioxidant capacity were measured in frozen serum samples collected from the same individuals in 1974 (13-15 years prior to the determination of case-control status). Compared to controls, atherosclerosis cases had significantly higher levels of serum total antioxidant capacity in 1974 than controls. This difference was almost entirely explained by increased serum concentration of uric acid in cases. In contrast with cross-sectional results, uric acid serum concentration in 1974, was significantly higher in cases than in controls, even after adjusting for the main cardiovascular risk factors. Cases had significantly lower levels of alpha-carotene in the 1974 sera than controls, but no other differences in serum antioxidant vitamin concentrations were observed. The higher serum uric acid concentration seemed associated with elevated total serum antioxidant capacity among individuals with atherosclerosis. This finding is consistent with experimental evidence suggesting that hyperuricemia may be a compensatory mechanism to counteract oxidative damage related to atherosclerosis and aging in humans.

Significant Correlation Between the Infant Gut Microbiome and Rotavirus Vaccine Response in Rural Ghana

PubMed Central

Harris, Vanessa C.; Armah, George; Fuentes, Susana; Korpela, Katri E.; Parashar, Umesh; Victor, John C.; Tate, Jacqueline; de Weerth, Carolina; Giaquinto, Carlo; Wiersinga, Willem Joost; Lewis, Kristen D. C.; de Vos, Willem M.

2017-01-01

Background. Rotavirus (RV) is the leading cause of diarrhea-related death in children worldwide and 95% of RV-associated deaths occur in Africa and Asia where RV vaccines (RVVs) have lower efficacy. We hypothesize that differences in intestinal microbiome composition correlate with the decreased RVV efficacy observed in poor settings. Methods. We conducted a nested, case-control study comparing prevaccination, fecal microbiome compositions between 6-week old, matched RVV responders and nonresponders in rural Ghana. These infants' microbiomes were then compared with 154 age-matched, healthy Dutch infants' microbiomes, assumed to be RVV responders. Fecal microbiome analysis was performed in all groups using the Human Intestinal Tract Chip. Results. We analyzed findings in 78 Ghanaian infants, including 39 RVV responder and nonresponder pairs. The overall microbiome composition was significantly different between RVV responders and nonresponders (FDR, 0.12), and Ghanaian responders were more similar to Dutch infants than nonresponders (P = .002). RVV response correlated with an increased abundance of Streptococcus bovis and a decreased abundance of the Bacteroidetes phylum in comparisons between both Ghanaian RVV responders and nonresponders (FDR, 0.008 vs 0.003) and Dutch infants and Ghanaian nonresponders (FDR, 0.002 vs 0.009). Conclusions. The intestinal microbiome composition correlates significantly with RVV immunogenicity and may contribute to the diminished RVV immunogenicity observed in developing countries. PMID:27803175

PPM1A Methylation Is Associated With Vascular Recurrence in Aspirin-Treated Patients.

PubMed

Gallego-Fabrega, Cristina; Carrera, Caty; Reny, Jean-Luc; Fontana, Pierre; Slowik, Agnieszka; Pera, Joanna; Pezzini, Alessandro; Serrano-Heras, Gemma; Segura, Tomás; Bin Dukhyil, Abdul-Aziz A; Martí-Fàbregas, Joan; Muiño, Elena; Cullell, Natalia; Montaner, Joan; Krupinski, Jerzy; Fernandez-Cadenas, Israel

2016-07-01

Despite great efforts by pharmacogenetic studies, the causes of aspirin failure to prevent the recurrence of ischemic events remain unclear. Our aim was to study whether epigenetics could be associated with the risk of vascular recurrence in aspirin-treated stroke patients. We performed an epigenetic joint analysis study in 327 patients treated with aspirin. In the discovery stage, we performed a nested case-control study in 38 matched ischemic stroke patients in whom 450 000 methylation sites were analyzed. Nineteen patients presented vascular recurrence after stroke, and 19 matched patients did not present vascular recurrence during the first year of follow-up. In a second stage, 289 new patients were analyzed by EpiTYPER. The following 3 differentially methylated candidate CpG sites, were identified in the discovery stage and analyzed in the second stage: cg26039762 (P=9.69×10(-06), RAF1), cg04985020 (P=3.47×10(-03), PPM1A), and cg08419850 (P=3.47×10(-03), KCNQ1). Joint analysis identified an epigenome-wide association for cg04985020 (PPM1A; P=1.78×10(-07)), with vascular recurrence in patients treated with aspirin. The pattern of differential methylation in PPM1A is associated with vascular recurrence in aspirin-treated stroke patients. © 2016 American Heart Association, Inc.

Nutritional Knowledge and Attitudes in Athletes With Physical Disabilities

PubMed Central

Rastmanesh, Reza; Taleban, Furugh Azam; Kimiagar, Masood; Mehrabi, Yadolah; Salehi, Moosa

2007-01-01

Context: Little is known about sport nutritional problems and requirements of athletes with physical disabilities. Objective: To compare the nutritional knowledge and attitudes of Iranian athletes with physical disabilities (APDs) after nutrition education. Because proper nutrition is important for both performance and injury healing, learning about the nutritional areas in which APDs are deficient may assist professionals in educating them. Design: Nested case-control study. Setting: Sport camp. Patients or Other Participants: Seventy-two APDs (42 APDs in the intervention group and 30 age-matched and sex-matched control APDs) and 10 coaches completed the study. Intervention(s): The APDs in the intervention group and their coaches were given nutrition education, which included a booklet with a simplified food guide pyramid, simple concepts about nutrition and weight loss, and four 3-hour courses. The APDs in the control group and their coaches were not given nutrition education. Main Outcome Measure(s): Subjects completed 2 nutritional questionnaires with both quantitative and qualitative components. Nutritional questionnaires were administered at 2 consecutive camps, 30 days apart, before and after nutrition education. Our questionnaires included a demographics section; 88 Likert scale and true-false questions; and 18 open-ended questions, 13 of which were specifically designed for APDs. Each APD completed two 3-day food records. Results: The APDs in the intervention group scored significantly higher after nutrition education and higher than the control group on the knowledge subscales and interest in nutrition. Although the nutrition knowledge score in this study was moderate, several specific areas of deficient nutritional knowledge were identified that are critical for the health of APDs. Our model of nutrition education was more effective than the usual instructions presented irregularly by coaches. Conclusions: Our findings suggest that Iranian APDs lack nutritional knowledge in areas critical to preventing nutrition-related health problems, especially components related to nutrition for athletes with disabilities. PMID:17597950

Intracranial haemorrhage and use of selective serotonin reuptake inhibitors

PubMed Central

de Abajo, Francisco J; Jick, Hershel; Derby, Laura; Jick, Susan; Schmitz, Stephen

2000-01-01

Aims In the past few years an increasing number of bleeding disorders have been reported in association with the use of selective serotonin reuptake inhibitors (SSRIs), including serious cases of intracranial haemorrhage, raising concerns about the safety of this class of drugs. The present study was performed to test the hypothesis of an increased risk of intracranial haemorrhage associated with the use of SSRIs. Methods We carried out a case-control study nested in a cohort of antidepressants users with the UK-based General Practice Research Database (GPRD) as the primary source of information. The study cohort encompassed subjects aged between 18 and 79 years who received a first-time prescription for any antidepressant from January, 1990 to October, 1997. Patients with presenting conditions or treatments that could be associated with an increased risk of intracranial haemorrhage were excluded from the cohort. Patients were followed-up until the occurrence of an idiopathic intracranial haemorrhage. Up to four controls per case, matched on age, sex, calendar time and practice were randomly selected from the study cohort. We estimated adjusted odds ratios and 95% confidence intervals of intracranial haemorrhage with current use of SSRIs and other antidepressants as compared with nonuse using conditional logistic regression. Results We identified 65 cases of idiopathic intracranial haemorrhage and 254 matched controls. Current exposure to SSRIs was ascertained in 7 cases (10.8%) and 24 controls (9.7%) resulting in an adjusted OR (95%CI) of 0.8 (0.3,2.3). The estimate for ‘other antidepressants’ was 0.7 (0.3,1.6). The effect measures were not modified by gender or age. No effect related to dose or treatment duration was detected. The risk estimates did not change according to the location of bleeding (intracerebral or subarachnoid). Conclusions Our results are not compatible with a major increased risk of intracranial haemorrhage among users of SSRIs or other antidepressants at large. However, smaller but still relevant increased risks cannot be ruled out. PMID:10886117

Effect of finite element model loading condition on fracture risk assessment in men and women: the AGES-Reykjavik study.

PubMed

Keyak, J H; Sigurdsson, S; Karlsdottir, G S; Oskarsdottir, D; Sigmarsdottir, A; Kornak, J; Harris, T B; Sigurdsson, G; Jonsson, B Y; Siggeirsdottir, K; Eiriksdottir, G; Gudnason, V; Lang, T F

2013-11-01

Proximal femoral (hip) strength computed by subject-specific CT scan-based finite element (FE) models has been explored as an improved measure for identifying subjects at risk of hip fracture. However, to our knowledge, no published study has reported the effect of loading condition on the association between incident hip fracture and hip strength. In the present study, we performed a nested age- and sex-matched case-control study in the Age Gene/Environment Susceptibility (AGES) Reykjavik cohort. Baseline (pre-fracture) quantitative CT (QCT) scans of 5500 older male and female subjects were obtained. During 4-7years follow-up, 51 men and 77 women sustained hip fractures. Ninety-seven men and 152 women were randomly selected as controls from a pool of age- and sex-matched subjects. From the QCT data, FE models employing nonlinear material properties computed FE-strength of the left hip of each subject in loading from a fall onto the posterolateral (FPL), posterior (FP) and lateral (FL) aspects of the greater trochanter (patent pending). For comparison, FE strength in stance loading (FStance) and total femur areal bone mineral density (aBMD) were also computed. For all loading conditions, the reductions in strength associated with fracture in men were more than twice those in women (p≤0.01). For fall loading specifically, posterolateral loading in men and posterior loading in women were most strongly associated with incident hip fracture. After adjusting for aBMD, the association between FP and fracture in women fell short of statistical significance (p=0.08), indicating that FE strength provides little advantage over aBMD for identifying female hip fracture subjects. However, in men, after controlling for aBMD, FPL was 424N (11%) less in subjects with fractures than in controls (p=0.003). Thus, in men, FE models of posterolateral loading include information about incident hip fracture beyond that in aBMD. © 2013.

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.

A comparison of artificial incubation and natural incubation hatching success of gopher tortoise (Gopherus polyphemus) eggs in southern Mississippi

USGS Publications Warehouse

Noel, Krista M.; Qualls, Carl P.; Ennen, Joshua R.

2012-01-01

Recent studies have found that Gopher Tortoise, Gopherus polyphemus, populations in southern Mississippi exhibit low recruitment, due in part to very low hatching success of their eggs. We sought to determine if the cause(s) of this low hatching success was related to egg quality (intrinsic factors), unsuitability of the nest environment (extrinsic factors), or a combination of the two. In 2003, hatching success was monitored simultaneously for eggs from the same clutches that were incubated in the laboratory and left to incubate in nests. A subset of randomly chosen eggs from each clutch was incubated in the laboratory under physical conditions that were known to be conducive to successful hatching to estimate the proportion of eggs that were capable of hatching in a controlled setting. Hatching success in the laboratory was compared with that of eggs incubated in natural nests to estimate the proportion of eggs that failed to hatch presumably from extrinsic factors. Laboratory hatching success was 58.8%, suggesting that roughly 40% of the eggs were intrinsically incapable of hatching even when incubated under controlled conditions. Hatching success in natural nests, 16.7%, was significantly lower than hatching success in the laboratory, suggesting that approximately 42.1% of eggs were capable of hatching but failed to hatch due to some extrinsic aspect(s) of the nest environment. Thus, the low hatching success of Gopher Tortoise eggs in southern Mississippi appears to be attributable to a combination of intrinsic (egg quality) and extrinsic (nest environment) factors.

Chemical exposures and respiratory cancer among Finnish woodworkers.

PubMed Central

Kauppinen, T P; Partanen, T J; Hernberg, S G; Nickels, J I; Luukkonen, R A; Hakulinen, T R; Pukkala, E I

1993-01-01

A case-control study of respiratory cancer, nested within a cohort of male woodworkers, was updated in Finland. The update extended the initial follow up of 3805 workers from 19 plants to 7307 workers from 35 plants. Each case of respiratory cancer (n = 136) diagnosed between 1957 and 1982 within the cohort was matched by year of birth with three controls (n = 408) from the cohort. Chemical exposures were assessed for the cases and the controls by a plant and period specific job exposure matrix. An excess of respiratory cancer was associated with phenol. Concomitant exposures to several other agents occurred as well, however, and no exposure-response relation for phenol was seen. An excess risk and an increasing exposure-response relation were found for engine exhaust from petrol and diesel driven factory trucks. The excess risk associated with pesticides was lower than in our previous study, an indication of qualitative and quantitative differences in exposure between the initial and augmented cohorts. Slightly increased risks were found for terpenes and mould spores, which may be due to chance although the contribution of occupational exposure cannot be ruled out. Exposure to wood dust, mainly from pine, spruce and birch, at a level of about 1 mg/m3, was not associated with lung cancer, upper respiratory cancer, or adenocarcinoma of the lung. PMID:8435346

Somatic mutations in benign breast disease tissue and risk of subsequent invasive breast cancer.

PubMed

Rohan, Thomas E; Miller, Christopher A; Li, Tiandao; Wang, Yihong; Loudig, Olivier; Ginsberg, Mindy; Glass, Andrew; Mardis, Elaine

2018-06-06

Insights into the molecular pathogenesis of breast cancer might come from molecular analysis of tissue from early stages of the disease. We conducted a case-control study nested in a cohort of women who had biopsy-confirmed benign breast disease (BBD) diagnosed between 1971 and 2006 at Kaiser Permanente Northwest and who were followed to mid-2015 to ascertain subsequent invasive breast cancer (IBC); cases (n = 218) were women with BBD who developed subsequent IBC and controls, individually matched (1:1) to cases, were women with BBD who did not develop IBC in the same follow-up interval as that for the corresponding case. Targeted sequence capture and sequencing were performed for 83 genes of importance in breast cancer. There were no significant case-control differences in mutation burden overall, for non-silent mutations, for individual genes, or with respect either to the nature of the gene mutations or to mutational enrichment at the pathway level. For seven subjects with DNA from the BBD and ipsilateral IBC, virtually no mutations were shared. This study, the first to use a targeted multi-gene sequencing approach on early breast cancer precursor lesions to investigate the genomic basis of the disease, showed that somatic mutations detected in BBD tissue were not associated with breast cancer risk.

Effects of colony relocation on diet and productivity of Caspian terns

USGS Publications Warehouse

Roby, D.D.; Collis, K.; Lyons, Donald E.; Craig, D.P.; Adkins, J.Y.; Myers, A.M.; Suryan, R.M.

2002-01-01

We investigated the efficacy of management to reduce the impact of Caspian tern (Sterna caspia) predation on survival of juvenile salmonids (Oncorhynchus spp.) in the Columbia River estuary. Resource managers sought to relocate approximately 9,000 pairs of terns nesting on Rice Island (river km 34) to East Sand Island (river km 8), where terns were expected to prey on fewer juvenile salmonids. Efforts to attract terns to nest on East Sand Island included creation of nesting habitat, use of social attraction techniques, and predator control, with concurrent efforts to discourage terns from nesting on Rice Island. This approach was successful in completely relocating the tern colony from Rice Island to East Sand Island by the third breeding season. Juvenile salmonids decreased and marine forage fishes (i.e., herring, sardine, anchovy, smelt, surfperch, Pacific sand lance) increased in the diet of Caspian terns nesting on East Sand Island, compared with terns nesting on Rice Island. During 1999 and 2000, the diet of terns nesting on Rice Island consisted of 77% and 90% juvenile salmonids, respectively, while during 1999, 2000, and 2001, the diet of terns nesting on East Sand Island consisted of 46%, 47%, and 33% juvenile salmonids, respectively. Nesting success of Caspian terns was consistently and substantially higher on East Sand Island than on Rice Island. These results indicate that relocating the Caspian tern colony was an effective management action for reducing predation on juvenile salmonids without harm to the population of breeding terns, at least in the short term. The success of this management approach largely was a consequence of the nesting and foraging ecology of Caspian terns: the species shifts breeding colony sites frequently in response to changing habitats, and the species is a generalist forager, preying on the most available forage fish near the colony.

Loneliness and depression among rural empty-nest elderly adults in Liuyang, China: a cross-sectional study

PubMed Central

Wang, Guojun; Hu, Mi; Xiao, Shui-yuan; Zhou, Liang

2017-01-01

Objective To compare loneliness, depressive symptoms and major depressive episodes between empty-nest and not-empty-nest older adults in rural areas of Liuyang city, Hunan, China. Methods A cross-sectional multi-stage random cluster survey was conducted from November 2011 to April 2012 in Liuyang, China. A total of 839 rural older residents aged 60 or above completed the survey (response rate 97.6%). In line with the definition of empty nest, 25 participants who had no children were excluded from the study, while the remaining 814 elderly adults with at least one child were included for analysis. Loneliness and depressive symptoms in rural elderly parents were assessed using the short-form UCLA Loneliness Scale (ULS-6) and the Geriatric Depression Scale (GDS). Major depressive episodes were diagnosed using the Structured Clinical Interview for DSM-IV (SCID-I). Results Significant differences were found between empty-nest and not-empty-nest older adults regarding loneliness (16.19±3.90 vs. 12.87±3.02, Cohen’s d=0.97), depressive symptoms (8.50±6.26 vs. 6.92±5.19, Cohen’s d=0.28) and the prevalence of major depressive episodes (10.1% vs. 4.6%) (all p<0.05). After controlling for demographic characteristics and physical disease, the differences in loneliness, depressive symptoms and major depressive episodes remained significant. Path analysis showed that loneliness mediated the relationship between empty-nest syndrome and depressive symptoms and major depressive episodes. Conclusion Loneliness and depression are more severe among empty-nest than not-empty-nest rural elderly adults. Loneliness was a mediating variable between empty-nest syndrome and depression. PMID:28988166

[Sensitivity and specificity of nested PCR pyrosequencing in hepatitis B virus drug resistance gene testing].

PubMed

Sun, Shumei; Zhou, Hao; Zhou, Bin; Hu, Ziyou; Hou, Jinlin; Sun, Jian

2012-05-01

To evaluate the sensitivity and specificity of nested PCR combined with pyrosequencing in the detection of HBV drug-resistance gene. RtM204I (ATT) mutant and rtM204 (ATG) nonmutant plasmids mixed at different ratios were detected for mutations using nested-PCR combined with pyrosequencing, and the results were compared with those by conventional PCR pyrosequencing to analyze the linearity and consistency of the two methods. Clinical specimens with different viral loads were examined for drug-resistant mutations using nested PCR pyrosequencing and nested PCR combined with dideoxy sequencing (Sanger) for comparison of the detection sensitivity and specificity. The fitting curves demonstrated good linearity of both conventional PCR pyrosequencing and nested PCR pyrosequencing (R(2)>0.99, P<0.05). Nested PCR showed a better consistency with the predicted value than conventional PCR, and was superior to conventional PCR for detection of samples containing 90% mutant plasmid. In the detection of clinical specimens, Sanger sequencing had a significantly lower sensitivity than nested PCR pyrosequencing (92% vs 100%, P<0.01). The detection sensitivity of Sanger sequencing varied with the viral loads, especially in samples with low viral copies (HBV DNA ≤3log10 copies/ml), where the sensitivity was 78%, significantly lower than that of pyrosequencing (100%, P<0.01). Neither of the two methods yielded positive results for the negative control samples, suggesting their good specificity. Compared with nested PCR and Sanger sequencing method, nested PCR pyrosequencing has a higher sensitivity especially in clinical specimens with low viral copies, which can be important for early detection of HBV mutant strains and hence more effective clinical 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.

Plasma Riboflavin and Vitamin B-6, but Not Homocysteine, Folate, or Vitamin B-12, Are Inversely Associated with Breast Cancer Risk in the European Prospective Investigation into Cancer and Nutrition-Varese Cohort.

PubMed

Agnoli, Claudia; Grioni, Sara; Krogh, Vittorio; Pala, Valeria; Allione, Alessandra; Matullo, Giuseppe; Di Gaetano, Cornelia; Tagliabue, Giovanna; Pedraglio, Samuele; Garrone, Giulia; Cancarini, Ilaria; Cavalleri, Adalberto; Sieri, Sabina

2016-06-01

One-carbon metabolism-important for DNA stability and integrity-may play a role in breast carcinogenesis. However, epidemiologic studies addressing this issue have yielded inconsistent results. We prospectively investigated associations between breast cancer and plasma folate, riboflavin, vitamin B-6, vitamin B-12, and homocysteine in women recruited to the Varese (Italy) cohort of the EPIC (European Prospective Investigation into Cancer and Nutrition) study. We performed a nested case-control study on women aged 35-65 y at recruitment with a median body mass index of 25.3 kg/m(2) who gave blood samples in 1987-1992 and again in 1993-1998. Breast cancer cases identified by 31 December 2009 were individually matched to controls. RRs of breast cancer (and subtypes defined by hormone receptor status) with 95% CIs were estimated by unconditional logistic regression, controlling for matching factors and breast cancer risk factors. After a median of 14.9 y, 276 breast cancer cases were identified and matched to 276 controls. Increasing plasma vitamin B-6 was associated with decreased risk of overall (RR: 0.78; 95% CI: 0.63, 0.96 for 1-SD increase), premenopausal (RR: 0.66; 95% CI: 0.48, 0.92 for 1-SD increase), estrogen receptor-positive (RR: 0.79; 95% CI: 0.63, 1.00 for 1-SD increase), and progesterone receptor-positive (RR: 0.72; 95% CI: 0.55, 0.95 for 1-SD increase) breast cancers. Increased plasma vitamin B-6 was also associated with decreased breast cancer risk in alcohol consumers (≥7 g/d) compared with consumption of <7 g/d or nonconsumption (RR: 0.71; 95% CI: 0.51, 0.99). High plasma riboflavin was associated with significantly lower risk in premenopausal women (RR: 0.45; 95% CI: 0.21, 0.94; highest compared with the lowest quartile, P trend = 0.021). Plasma homocysteine, folate, and vitamin B-12 were not associated with breast cancer risk. High plasma vitamin B-6 and riboflavin may lower breast cancer risk, especially in premenopausal women. Additional research is necessary to further explore these associations. © 2016 American Society for Nutrition.

Range resolution improvement in passive bistatic radars using nested FM channels and least squares approach

NASA Astrophysics Data System (ADS)

Arslan, Musa T.; Tofighi, Mohammad; Sevimli, Rasim A.; ćetin, Ahmet E.

2015-05-01

One of the main disadvantages of using commercial broadcasts in a Passive Bistatic Radar (PBR) system is the range resolution. Using multiple broadcast channels to improve the radar performance is offered as a solution to this problem. However, it suffers from detection performance due to the side-lobes that matched filter creates for using multiple channels. In this article, we introduce a deconvolution algorithm to suppress the side-lobes. The two-dimensional matched filter output of a PBR is further analyzed as a deconvolution problem. The deconvolution algorithm is based on making successive projections onto the hyperplanes representing the time delay of a target. Resulting iterative deconvolution algorithm is globally convergent because all constraint sets are closed and convex. Simulation results in an FM based PBR system are presented.

A multicenter, case-control study on risk factors for antepartum stillbirth.

PubMed

Facchinetti, Fabio; Alberico, Salvatore; Benedetto, Chiara; Cetin, Irene; Cozzolino, Sabrina; Di Renzo, Gian Carlo; Del Giovane, Cinzia; Ferrari, Francesca; Mecacci, Federico; Menato, Guido; Tranquilli, Andrea L; Baronciani, Dante

2011-03-01

As the influence of socio-demographic variables, lifestyle and medical conditions on the epidemiology of stillbirth (SB) is modified by population features, we aimed at investigating the role played by these factors on the incidence of SB in a developed country. Multivariate logistic regression analysis (OR with 95% CI) was utilized in a prospective multicentre nested case-control study to compare in a 1:2 ratio stillborn of >22 weeks gestation with matched for gestational age live-born (LB) infants. Intrapartum SB were excluded. Two hundred fifty-four consecutive SBs and 497 LBs were enrolled. Socio-demographic variables were equally distributed. Fetal malformations (7.96, 2.69-23.55), severe intrauterine growth restriction (IUGR) (birthweight ≤ 5(th) %ile) (4.32, 2.27?8.24), BMI > 25 (2.87, 1.90-4.33), and preeclampsia (PE, 0.40, 0.21-0.77) were recognized as independent predictors for SB. At term, only BMI > 25 was associated with SB (7.70, 2.9-20.5). Fetal malformations, severe IUGR and maternal BMI > 25 were associated with a significant increase in the risk of SB; PE presented instead a protective role. Maternal BMI > 25 was the only risk factor for SB identified in term pregnancies.

Statistical analysis of donation--transfusion data with complex correlation.

PubMed

Reilly, Marie; Szulkin, Robert

2007-12-30

Blood-borne transmission of disease is estimated from linked data records from blood donors and transfusion recipients. However, such data are characterized by complex correlation due to donors typically contributing many donations and recipients being transfused with multiple units of blood product. In this paper, we present a method for analysing such data, by using a modification of a nested case-control design. For recipients who develop the disease of interest (cases) and their matched controls, all donors who contributed blood to these individuals define clusters or 'families' of related individuals. Using a Cox regression model for the hazard of the individuals within clusters of donors, we estimate the risk of transmission, and a bootstrap step provides valid standard errors provided the clusters are independent. As an illustration, we apply the method to the analysis of a large database of Swedish donor and recipient records linked to the population cancer register. We investigate whether there is an increased risk of cancer in recipients transfused with blood from donors who develop cancer after donating. Our method provides a powerful alternative to the small 'look-back' studies typical of transfusion medicine and can make an important contribution to haemovigilance efforts. Copyright (c) 2007 John Wiley & Sons, Ltd.

Elevated maternal C-reactive protein and increased risk of schizophrenia in a national birth cohort.

PubMed

Canetta, Sarah; Sourander, Andre; Surcel, Heljä-Marja; Hinkka-Yli-Salomäki, Susanna; Leiviskä, Jaana; Kellendonk, Christoph; McKeague, Ian W; Brown, Alan S

2014-09-01

The objective of the present study was to investigate an association between early gestational C-reactive protein, an established inflammatory biomarker, prospectively assayed in maternal sera, and schizophrenia in a large, national birth cohort with an extensive serum biobank. A nested case-control design from the Finnish Prenatal Study of Schizophrenia cohort was utilized. A total of 777 schizophrenia cases (schizophrenia, N=630; schizoaffective disorder, N=147) with maternal sera available for C-reactive protein testing were identified and matched to 777 control subjects in the analysis. Maternal C-reactive protein levels were assessed using a latex immunoassay from archived maternal serum specimens. Increasing maternal C-reactive protein levels, classified as a continuous variable, were significantly associated with schizophrenia in offspring (adjusted odds ratio=1.31, 95% confidence interval=1.10-1.56). This finding remained significant after adjusting for potential confounders, including maternal and parental history of psychiatric disorders, twin/singleton birth, urbanicity, province of birth, and maternal socioeconomic status. This finding provides the most robust evidence to date that maternal inflammation may play a significant role in schizophrenia, with possible implications for identifying preventive strategies and pathogenic mechanisms in schizophrenia and other neurodevelopmental disorders.

Breast cancer among women in Michigan following exposure to brominated flame retardants

PubMed Central

Terrell, Metrecia L; Rosenblatt, Karin A; Wirth, Julie; Cameron, Lorraine L; Marcus, Michele

2017-01-01

In this updated follow-up, we investigated the breast cancer experience among women in Michigan exposed to brominated flame retardants, some 30 years following exposure. Michigan residents were enrolled in a study cohort after exposure to polybrominated biphenyls (PBBs) through the consumption of contaminated food products. PBB concentrations were measured in serum at the time of enrolment. Cancer experience was determined by linkage to the Michigan Cancer Registry. We conducted a nested case–control study that included 51 women diagnosed with breast cancer during 1974–2004 and 202 age-matched controls. While the data suggest an increase in breast cancer risk with higher PBB exposure, this did not reach statistical significance. The OR of having breast cancer among women with PBB concentrations ≥10 ng/mL compared to women with PBB concentrations at or below the limit of detection of 1 ng/mL was 2.60, 95% CI 0.93 to 7.27, (p=0.07), when adjusted for age and family history of cancer in a first-degree female relative. It remains important to examine exposure to brominated chemicals and possible health effects, and to continue following the cancer experience of participants in this study. PMID:27312402

Circulating 25-Hydroxyvitamin D and Risk of Kidney Cancer

PubMed Central

Gallicchio, Lisa; Moore, Lee E.; Stevens, Victoria L.; Ahn, Jiyoung; Albanes, Demetrius; Hartmuller, Virginia; Setiawan, V. Wendy; Helzlsouer, Kathy J.; Yang, Gong; Xiang, Yong-Bing; Shu, Xiao-Ou; Snyder, Kirk; Weinstein, Stephanie J.; Yu, Kai; Zeleniuch-Jacquotte, Anne; Zheng, Wei; Cai, Qiuyin; Campbell, David S.; Chen, Yu; Chow, Wong-Ho; Horst, Ronald L.; Kolonel, Laurence N.; McCullough, Marjorie L.; Purdue, Mark P.; Koenig, Karen L.

2010-01-01

Although the kidney is a major organ for vitamin D metabolism, activity, and calcium-related homeostasis, little is known about whether this nutrient plays a role in the development or the inhibition of kidney cancer. To address this gap in knowledge, the authors examined the association between circulating 25-hydroxyvitamin D (25(OH)D) and kidney cancer within a large, nested case-control study developed as part of the Cohort Consortium Vitamin D Pooling Project of Rarer Cancers. Concentrations of 25(OH)D were measured from 775 kidney cancer cases and 775 age-, sex-, race-, and season-matched controls from 8 prospective cohort studies. Overall, neither low nor high concentrations of circulating 25(OH)D were significantly associated with kidney cancer risk. Although the data showed a statistically significant decreased risk for females (odds ratio = 0.31, 95% confidence interval: 0.12, 0.85) with 25(OH)D concentrations of ≥75 nmol/L, the linear trend was not statistically significant and the number of cases in this category was small (n = 14). The findings from this consortium-based study do not support the hypothesis that vitamin D is inversely associated with the risk of kidney cancer overall or with renal cell carcinoma specifically. PMID:20562187

Does gender bias in cardiac stress testing still exist? A videographic analysis nested in a randomized controlled trial.

PubMed

Nestler, David M; Gilani, Waqas I; Anderson, Ryan T; Bellolio, M Fernanda; Branda, Megan E; LeBlanc, Annie; Phelan, Sean; Campbell, Ronna L; Hess, Erik P

2017-01-01

Despite a high prevalence of coronary heart disease in both genders, studies show a gender disparity in evaluation whereby women are less likely than men to undergo timely or comprehensive cardiac investigation. Using videographic analysis, we sought to quantify gender differences in provider recommendations and patient evaluations. We analyzed video recordings from our Chest Pain Choice trial, a single center patient-level randomized trial in which emergency department patients with chest pain being considered for cardiac stress testing were randomized to shared decision-making or usual care. Patient-provider interactions were video recorded. We compared characteristics and outcomes by gender. Of the 204 patients enrolled (101 decision aid; 103 usual care), 120 (58.8%) were female. Of the 75 providers evaluated, 20 (26.7%) were female. The mean (SD) pretest probability of acute coronary syndrome was lower in women [3.7% (2.2) vs 6.7% (4.4), P=.0002]. There was no gender effect on duration of discussion, clinician recommendations, OPTION scores, patient perceptions, or eventual patient dispositions. When the clinician and patient gender matched, OPTION scores were lower (interaction P=.002), and patients were less likely to find the information to be very helpful (interaction P=.10). Despite a lower pretest probability of acute coronary syndrome in women, we did not observe any significant gender disparity in how patients were managed and evaluated. When the patients' and providers' gender matched, the provider involved them less in the decision making process, and the information provided was less helpful than when the genders did not match. Copyright © 2016 Elsevier Inc. All rights reserved.

Effects of acute alcohol withdrawal on nest building in mice selectively bred for alcohol withdrawal severity.

PubMed

Greenberg, Gian D; Phillips, Tamara J; Crabbe, John C

2016-10-15

Nest building has been used to assess thermoregulatory behavior and positive motivational states in mice. There are known genetic influences on ethanol withdrawal severity as well as individual/thermoregulatory nest building. Withdrawal Seizure-Prone (WSP-1, WSP-2) and Withdrawal Seizure-Resistant (WSR-1, WSR-2) mice were selectively bred for high vs low handling-induced convulsion (HIC) severity, respectively, during withdrawal from chronic ethanol vapor inhalation. They also differ in HIC severity during withdrawal from an acute, 4g/kg ethanol injection. In our initial study, withdrawal from an acute dose of ethanol dose-dependently impaired nest building over the initial 24h of withdrawal in genetically segregating Withdrawal Seizure Control (WSC) mice. In two further studies, acute ethanol withdrawal suppressed nest building for up to two days in WSP-1 females. Deficits in nest building from ethanol were limited to the initial 10h of withdrawal in WSR-1 females and to the initial 24h of withdrawal in WSP-1 and WSR-1 males. Effects of ethanol on nest building for up to two days were found in WSP-2 and WSR-2 mice of both sexes. Nest building deficits in female mice from the first replicate could not be explained by a general decrease in locomotor behavior. These results suggest that nest building is a novel behavioral phenotype for indexing the severity of acute ethanol withdrawal, and that genes contributing to this trait differ from those affecting acute withdrawal HIC severity. Published by Elsevier Inc.

[Duration of the pre-nesting period and its relation with social organization in sandpipers (Charadrii, Aves) nesting in north-east Yakutia].

PubMed

Gavrilov, V V

2013-01-01

Investigations were carried out at two stations of Ornithological Unit, IBPN FEB RAS, located in Nizhnekolymsk District, Yakutia, starting from May 18-20 in 1984, 1985, 1987, 1988 and 1990. Duration of the pre-nesting period in 11 sandpiper species with different social organization was studied and compared with each other by allometric equations. As a characteristic of bird size the body mass was selected. Sandpipers come flying to the tundra at almost critical temperatures, to begin breeding as early as possible. Tining of breeding depends on birds feeding manner and the proximity to sites of overwintering. Duration of the pre-nesting period is invariable for every bird species and sex. There are sexual distinctions in time spent for the pre-nesting period in jointly-nesting sandpipers. The exponents in allometric equations that relate duration of the pre-nesting period with body mass are constant within a particular sex and differ between males and females. In different sexes, time spent for the pre-nesting period depends on mating, parental, and territorial systems. In sandpipers' males and females, this time is determined by the type of social organization. Relatively large sandpiper species seek to shortening of the pre-nesting period calendar time, which constrains their social organization. Monogamy and pair parental care lead to a necessity for spatial population structure to be controlled more strictly and maintained for a longer time. This, in turn, causes the increasing of males' time expenditures for such a behavior.

Nest survival modelling using a multi-species approach in forests managed for timber and biofuel feedstock

USGS Publications Warehouse

Loman, Zachary G.; Monroe, Adrian; Riffell, Samuel K.; Miller, Darren A.; Vilella, Francisco; Wheat, Bradley R.; Rush, Scott A.; Martin, James A.

2018-01-01

Switchgrass (Panicum virgatum) intercropping is a novel forest management practice for biomass production intended to generate cellulosic feedstocks within intensively managed loblolly pine‐dominated landscapes. These pine plantations are important for early‐successional bird species, as short rotation times continually maintain early‐successional habitat. We tested the efficacy of using community models compared to individual surrogate species models in understanding influences on nest survival. We analysed nest data to test for differences in habitat use for 14 bird species in plots managed for switchgrass intercropping and controls within loblolly pine (Pinus taeda) plantations in Mississippi, USA.We adapted hierarchical models using hyper‐parameters to incorporate information from both common and rare species to understand community‐level nest survival. This approach incorporates rare species that are often discarded due to low sample sizes, but can inform community‐level demographic parameter estimates. We illustrate use of this approach in generating both species‐level and community‐wide estimates of daily survival rates for songbird nests. We were able to include rare species with low sample size (minimum n = 5) to inform a hyper‐prior, allowing us to estimate effects of covariates on daily survival at the community level, then compare this with a single‐species approach using surrogate species. Using single‐species models, we were unable to generate estimates below a sample size of 21 nests per species.Community model species‐level survival and parameter estimates were similar to those generated by five single‐species models, with improved precision in community model parameters.Covariates of nest placement indicated that switchgrass at the nest site (<4 m) reduced daily nest survival, although intercropping at the forest stand level increased daily nest survival.Synthesis and applications. Community models represent a viable method for estimating community nest survival rates and effects of covariates while incorporating limited data for rarely detected species. Intercropping switchgrass in loblolly pine plantations slightly increased daily nest survival at the research plot scale (0.1 km2), although at a local scale (50 m2) switchgrass negatively influenced nest survival. A likely explanation is intercropping shifted community composition, favouring species with greater disturbance tolerance.

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...

Songbird abundance and parasatism differ between urban and rural shrublands

Treesearch

Dirk E. Burhans; Frank R. Thompson

2006-01-01

Many studies have examined differences in avian community composition between urban and rural habitats, but few, if any, have looked at nesting success of urban shrubland birds in a replicated fashion while controlling for habitat. We tested factors affecting nest survival, parasitism by the Brown-headed Cowbird (Molothrus ater), and species abundance in shrubland...

Rotenone, Paraquat, and Parkinson’s Disease

PubMed Central

Tanner, Caroline M.; Kamel, Freya; Ross, G. Webster; Hoppin, Jane A.; Goldman, Samuel M.; Korell, Monica; Marras, Connie; Bhudhikanok, Grace S.; Kasten, Meike; Chade, Anabel R.; Comyns, Kathleen; Richards, Marie Barber; Meng, Cheryl; Priestley, Benjamin; Fernandez, Hubert H.; Cambi, Franca; Umbach, David M.; Blair, Aaron; Sandler, Dale P.; Langston, J. William

2011-01-01

Background Mitochondrial dysfunction and oxidative stress are pathophysiologic mechanisms implicated in experimental models and genetic forms of Parkinson’s disease (PD). Certain pesticides may affect these mechanisms, but no pesticide has been definitively associated with PD in humans. Objectives Our goal was to determine whether pesticides that cause mitochondrial dysfunction or oxidative stress are associated with PD or clinical features of parkinsonism in humans. Methods We assessed lifetime use of pesticides selected by mechanism in a case–control study nested in the Agricultural Health Study (AHS). PD was diagnosed by movement disorders specialists. Controls were a stratified random sample of all AHS participants frequency-matched to cases by age, sex, and state at approximately three controls: one case. Results In 110 PD cases and 358 controls, PD was associated with use of a group of pesticides that inhibit mitochondrial complex I [odds ratio (OR) = 1.7; 95% confidence interval (CI), 1.0–2.8] including rotenone (OR = 2.5; 95% CI, 1.3–4.7) and with use of a group of pesticides that cause oxidative stress (OR = 2.0; 95% CI, 1.2–3.6), including paraquat (OR = 2.5; 95% CI, 1.4–4.7). Conclusions PD was positively associated with two groups of pesticides defined by mechanisms implicated experimentally—those that impair mitochondrial function and those that increase oxidative stress—supporting a role for these mechanisms in PD pathophysiology. PMID:21269927

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.

Sound settlement: noise surpasses land cover in explaining breeding habitat selection of secondary cavity-nesting birds.

PubMed

Kleist, Nathan J; Guralnick, Robert P; Cruz, Alexander; Francis, Clinton D

2017-01-01

Birds breeding in heterogeneous landscapes select nest sites by cueing in on a variety of factors from landscape features and social information to the presence of natural enemies. We focus on determining the relative impact of anthropogenic noise on nest site occupancy, compared to amount of forest cover, which is known to strongly influence the selection process. We examine chronic, industrial noise from natural gas wells directly measured at the nest box as well as site-averaged noise, using a well-established field experimental system in northwestern New Mexico. We hypothesized that high levels of noise, both at the nest site and in the environment, would decrease nest box occupancy. We set up nest boxes using a geospatially paired control and experimental site design and analyzed four years of occupancy data from four secondary cavity-nesting birds common to the Colorado Plateau. We found different effects of noise and landscape features depending on species, with strong effects of noise observed in breeding habitat selection of Myiarchus cinerascens, the Ash-throated Flycatcher, and Sialia currucoides, the Mountain Bluebird. In contrast, the amount of forest cover less frequently explained habitat selection for those species or had a smaller standardized effect than the acoustic environment. Although forest cover characterization and management is commonly employed by natural resource managers, our results show that characterizing and managing the acoustic environment should be an important tool in protected area management. © 2016 by the Ecological Society of America.

The role of geomagnetic cues in green turtle open sea navigation.

PubMed

Benhamou, Simon; Sudre, Joël; Bourjea, Jérome; Ciccione, Stéphane; De Santis, Angelo; Luschi, Paolo

2011-01-01

Laboratory and field experiments have provided evidence that sea turtles use geomagnetic cues to navigate in the open sea. For instance, green turtles (Chelonia mydas) displaced 100 km away from their nesting site were impaired in returning home when carrying a strong magnet glued on the head. However, the actual role of geomagnetic cues remains unclear, since magnetically treated green turtles can perform large scale (>2000 km) post-nesting migrations no differently from controls. In the present homing experiment, 24 green turtles were displaced 200 km away from their nesting site on an oceanic island, and tracked, for the first time in this type of experiment, with Global Positioning System (GPS), which is able to provide much more frequent and accurate locations than previously used tracking methods. Eight turtles were magnetically treated for 24-48 h on the nesting beach prior to displacement, and another eight turtles had a magnet glued on the head at the release site. The last eight turtles were used as controls. Detailed analyses of water masses-related (i.e., current-corrected) homing paths showed that magnetically treated turtles were able to navigate toward their nesting site as efficiently as controls, but those carrying magnets were significantly impaired once they arrived within 50 km of home. While green turtles do not seem to need geomagnetic cues to navigate far from the goal, these cues become necessary when turtles get closer to home. As the very last part of the homing trip (within a few kilometers of home) likely depends on non-magnetic cues, our results suggest that magnetic cues play a key role in sea turtle navigation at an intermediate scale by bridging the gap between large and small scale navigational processes, which both appear to depend on non-magnetic cues.

Maternal and littermate deprivation disrupts maternal behavior and social-learning of food preference in adulthood: tactile stimulation, nest odor, and social rearing prevent these effects.

PubMed

Melo, Angel I; Lovic, Vedran; Gonzalez, Andrea; Madden, Melissa; Sinopoli, Katia; Fleming, Alison S

2006-04-01

Maternal and littermate (social) separation, through artificial rearing (AR), disrupts the development of subsequent maternal behavior and social learning in rats. The addition of maternal-licking-like stimulation during AR, partially reverses some of these effects. However, little is know about the role of social stimuli from littermates and nest odors during the preweaning period, in the development of the adult maternal behavior and social learning. The purpose of this study was to examine the effects of peer- and peer-and-odor rearing on the development of maternal behavior and social learning in rats. Female pups were reared with mothers (mother reared-MR) or without mothers (AR) from postnatal day (PND) 3. AR rats received three different treatments: (1) AR-CONTROL group received minimal tactile stimulation, (2) AR-ODOR females received exposure to maternal nest material inside the AR-isolation-cup environment, (3) AR-SOCIAL group was reared in the cup with maternal nest material and a conspecific of the same-age and same-sex and received additional tactile stimulation. MR females were reared by their mothers in the nest and with conspecifics. In adulthood, rats were tested for maternal behavior towards their own pups and in a social learning task. Results confirm our previous report that AR impairs performance of maternal behavior and the development of a social food preference. Furthermore, social cues from a littermate, in combination with tactile stimulation and the nest odor, reversed the negative effects of complete isolation (AR-CONTROL) on some of the above behaviors. Exposure to the odor alone also had effects on some of these olfactory-mediated behaviors. These studies indicate that social stimulation from littermates during the preweaning period, in combination with odor from the nest and tactile stimulation, contributes to the development of affiliative behaviors. Copyright (c) 2006 Wiley Periodicals, Inc.

Sitting in the sun: Nest microhabitat affects incubation temperatures in seabirds.

PubMed

Hart, Lorinda A; Downs, Colleen T; Brown, Mark

2016-08-01

During incubation parent birds are committed to a nest site and endure a range of ambient conditions while regulating egg temperatures. Using artificial eggs containing temperature loggers alongside ambient temperature (Ta) controls, incubation profiles were determined for four tropical seabird species at different nest site locations. Camera traps were used for ad-hoc behavioural incubation observations. Eggs experienced a range of temperatures during incubation and varied significantly between species and in some cases between different microhabitats within a species. Such variation has important consequences in the phenotypic expression of both physical and physiological traits of chicks, and ultimately species fitness. Exposed nest sites were more strongly correlated to Tas. Camera traps highlighted different incubation strategies employed by these species that could be related to trade-offs in predator defence, feeding habits, and temperature regulation of eggs. This study provides evidence that species with similar breeding habits could be affected by environmental stressors in similar ways and that the differences shown in nest site selection could negate some of these effects. We propose that habitats providing suitable nest microclimates will become increasingly important for the successful breeding of seabird species, particularly under predicted climate change scenarios. Copyright © 2016 Elsevier Ltd. All rights reserved.

A prototypic small molecule database for bronchoalveolar lavage-based metabolomics

NASA Astrophysics Data System (ADS)

Walmsley, Scott; Cruickshank-Quinn, Charmion; Quinn, Kevin; Zhang, Xing; Petrache, Irina; Bowler, Russell P.; Reisdorph, Richard; Reisdorph, Nichole

2018-04-01

The analysis of bronchoalveolar lavage fluid (BALF) using mass spectrometry-based metabolomics can provide insight into lung diseases, such as asthma. However, the important step of compound identification is hindered by the lack of a small molecule database that is specific for BALF. Here we describe prototypic, small molecule databases derived from human BALF samples (n=117). Human BALF was extracted into lipid and aqueous fractions and analyzed using liquid chromatography mass spectrometry. Following filtering to reduce contaminants and artifacts, the resulting BALF databases (BALF-DBs) contain 11,736 lipid and 658 aqueous compounds. Over 10% of these were found in 100% of samples. Testing the BALF-DBs using nested test sets produced a 99% match rate for lipids and 47% match rate for aqueous molecules. Searching an independent dataset resulted in 45% matching to the lipid BALF-DB compared to<25% when general databases are searched. The BALF-DBs are available for download from MetaboLights. Overall, the BALF-DBs can reduce false positives and improve confidence in compound identification compared to when general databases are used.

Association Between Smoking Status, Preoperative Exhaled Carbon Monoxide Levels, and Postoperative Surgical Site Infection in Patients Undergoing Elective Surgery

PubMed Central

Martin, David P.; Thompson, Rodney; Schroeder, Darrell R.; Hanson, Andrew C.; Warner, David O.

2017-01-01

Importance Cigarette smoking is a risk factor for many perioperative complications, including surgical site infection (SSI). The duration of abstinence from smoking required to reduce this risk is unknown. Objectives To evaluate if abstinence from smoking on the day of surgery is associated with a decreased frequency of SSI in patients who smoke cigarettes and to confirm that smoking is significantly independently associated with SSI when adjustment is made for potentially relevant covariates, such as body mass index. Design, Setting, and Participants In this observational, nested, matched case-control study, 2 analyses were performed at an academic referral center in the upper Midwest. Cases included all patients undergoing elective surgical procedures at Mayo Clinic, Rochester, Minnesota, between January 1, 2009, and July 31, 2014 (inclusive) who subsequently developed an SSI. Controls for both analyses were matched on age, sex, and type of surgery. Exposures Smoking status and preoperative exhaled carbon monoxide level, assessed by nurses in the preoperative holding area. Patients were classified as smoking on the day of surgery if they self-reported smoking or if their preoperative exhaled carbon monoxide level was 10 ppm or higher. Main Outcomes and Measures Surgical site infection after a surgical procedure at Mayo Clinic, Rochester, as identified by routine clinical surveillance using National Healthcare Safety Network criteria. Results Of the 6919 patients in the first analysis, 3282 (47%) were men and 3637 (53%) were women; median age (interquartile range) for control and SSI cases was 60 (48-70). Of the 392 patients in the second analysis, 182 (46%) were men and 210 (54%) were women; median age (interquartile range) for controls was 53 (45-49) and for SSI cases was 51 (45-60). During the study period, approximately 2% of surgical patients developed SSI annually. Available for the first analysis (evaluating the influence of current smoking status) were 2452 SSI cases matched to 4467 controls. The odds ratio for smoking and SSI was 1.51 (95% CI, 1.20-1.90; P < .001), which remained statistically significant after adjusting for covariates. In the second analysis (evaluating the influence of smoking on the day of surgery), there were 137 SSI cases matched to 255 controls. The odds ratio for smoking on the day of surgery and SSI was 1.96 (95% CI, 1.23-3.13; P < .001), which remained statistically significant after adjusting for covariates. Preoperative exhaled carbon monoxide level was not associated with the frequency of SSI, suggesting that the association between smoking on the day of surgery and SSI was not related to preoperative exhaled carbon monoxide levels. Conclusions and Relevance Current smoking is associated with the development of SSI, and smoking on the day of surgery is independently associated with the development of SSI. These data cannot distinguish whether abstinence per se reduces risk or whether it is associated with other factors that may be causative. PMID:28199450

Influence of corticosterone treatment on nestling begging in Florida scrub-jays (Aphelocoma coerulescens).

PubMed

Elderbrock, Emily K; Small, Thomas W; Schoech, Stephan J

2018-04-01

Altricial young are dependent on adults for protection and food, and they display nutritional need by begging to elicit feeding from parents. Begging at high levels can be energetically expensive and attract predators; thus, an individual must balance its nutritional needs with these potential costs. Further, because a parent is limited in the amount of food it can provide, begging can contribute to both parent-offspring conflict and sibling-sibling competition. Many extrinsic and intrinsic factors may contribute to begging behavior. One intrinsic factor of interest is corticosterone (CORT), a metabolic hormone hypothesized to play a role in regulating a nestling's begging behavior. We investigated the hypothesis that increased exposure to CORT influences nestling begging behavior in an altricial species, the Florida scrub-jay (Aphelocoma coerulescens). We treated one nestling per treatment nest with a twice-daily dose of exogenous hormone via a CORT-injected waxworm, whereas a second individual received a vehicle-injected waxworm. We monitored individual nestling and adult behavior at all nests with the use of high-definition video cameras on several days during treatment. We found no difference in begging rate between CORT fed and vehicle fed nestlings within a treatment nest. Further, to determine whether CORT treatment had indirect effects on the entire brood, we monitored additional nests, in which nestlings were not manipulated. When treatment and controls were compared, overall begging rates of nestlings in treatment nests were greater than those in control nests. This result suggests that CORT treatment of an individual altered its behavior, as well as that of its siblings. Copyright © 2017 Elsevier Inc. All rights reserved.

Experimental removal of woody vegetation does not increase nesting success or fledgling production in two grassland sparrows (Ammodramus) in Pennsylvania

USGS Publications Warehouse

Hill, Jason M.; Diefenbach, Duane R.

2013-01-01

The influence of vegetation structure on the probability of daily nest survival (DNS) for grassland passerines has received considerable attention. Some correlative studies suggest that the presence of woody vegetation lowers DNS. Over 3 years (2009–2011), we monitored 215 nests of the Grasshopper Sparrow (Ammodramus savannarum) and Henslow's Sparrow (A. henslowii) on 162 ha of reclaimed surface-mine grasslands in Pennsylvania. We removed shrubs from treatment plots with ≤36% areal coverage of woody vegetation in a before-after-control-impact-pairs (BACIP) design framework. Daily nest survival (95% CI: 0.94–0.96) was as high as previous studies have reported but was not associated with woody vegetative cover, proximity to woody vegetation, or woody stem density. Variation in DNS was best explained by increasing nonwoody-vegetation height. Grasshopper Sparrow fledgling production on treatment plots in 2010 (95% CI: 3.3–4.7) and 2011 (95% CI: 3.8–5.0) was similar to baseline conditions of treatment plots (95% CI: 3.4–4.9) and control plots (95% CI: 3.2–4.5) in 2009. Fledgling production was associated with thatch depth (β ± SE = 0.13 ± 0.09) and bare ground (β ± SE = -2.62 ± 1.29) adjacent to the nest and plot woody vegetative cover ( ± SE = -3.09 ± 1.02). Our experimental research suggests that overall reproductive success of Grasshopper and Henslow's sparrows on reclaimed surfacemine grasslands is driven by a suite of largely nonwoody—vegetation components, and both species can successfully nest and produce young in habitats with greater amounts of scattered woody vegetation than has generally been considered.

Disease Resistance in the Drywood Termite, Incisitermes schwarzi: Does Nesting Ecology Affect Immunocompetence?

PubMed Central

Calleri, Daniel V.; Rosengaus, Rebeca B.; Traniello, James F.A.

2010-01-01

Termites live in nests that can differ in microbial load and thus vary in degree of disease risk. It was hypothesized that termite investment in immune response would differ in species living in nest environments that vary in the richness and abundance of microbes. Using the drywood termite, Incisitermes schwarzi Banks (Isoptera: Kalotermitidae), as a model for species having low nest and cuticular microbial loads, the susceptibility of individuals and groups to conidia of the entomopathogenic fungus, Metarhizium anisopliae Sorokin (Hypocreales: Clavicipitaceae), was examined. The survivorship of I. schwarzi was compared to that of the dampwood termite, Zootermopsis angusticollis Hagen (Termopsidae), a species with comparatively high microbial loads. The results indicated that I. schwarzi derives similar benefits from group living as Z. angusticollis: isolated termites had 5.5 times the hazard ratio of death relative to termites nesting in groups of 25 while termites in groups of 10 did not differ significantly from the groups of 25. The results also indicated, after controlling for the influence of group size and conidia exposure on survivorship, that Z. angusticollis was significantly more susceptible to fungal infection than I. schwarzi, the former having 1.6 times the hazard ratio of death relative to drywood termites. Thus, disease susceptibility and individual investment in immunocompetence may not be dependent on interspecific variation in microbial pressures. The data validate prior studies indicating that sociality has benefits in infection control and suggest that social mechanisms of disease resistance, rather than individual physiological and immunological adaptations, may have been the principle target of selection related to variation in infection risk from microbes in the nest environment of different termite species. PMID:20572790

Plasma Enterolactone and Breast Cancer Risk in the Nurses’ Health Study II

PubMed Central

Xie, Jing; Tworoger, Shelley S.; Franke, Adrian A.; Terry, Kathryn L.; Rice, Megan S.; Rosner, Bernard A.; Willett, Walter C.; Hankinson, Susan E.; Eliassen, A. Heather

2013-01-01

Background Lignans are plant-based phytoestrogens with both estrogenic and anti-estrogenic properties that may be important for breast carcinogenesis. Retrospective studies have observed decreased breast cancer risk associated with high circulating enterolactone concentrations, a biomarker of lignan intake, but results from prospective studies are conflicting. Methods To prospectively examine this association, we measured plasma enterolactone levels in 802 breast cancer cases and 802 matched controls nested among predominantly premenopausal women in the Nurses’ Health Study II (NHSII) cohort. We used conditional logistic regression and polytomous logistic regression models, adjusting for known breast cancer risk factors, to calculate relative risks (RR) and 95% confidence intervals (CI). Results Compared to women with enterolactone concentrations ≤ 4nmol/L, the multivariate adjusted RRs for breast cancer were 1.18 (95% CI: 0.86–1.62), 0.91 (95% CI: 0.66–1.25), and 0.96 (95% CI: 0.70–1.33) for women with enterolactone levels in the 2nd to the 4th quartiles, respectively; Ptrend=0.60. Results were similar across tumors defined by estrogen and progesterone receptor status. Among premenopausal women with follicular estradiol levels below the median (<47 pg/mL), women in the highest category of enterolactone levels had a 51% lower breast cancer risk compared to those in the lowest category (95% CI: 0.27–0.91); Ptrend=0.02. No association was observed among women with high follicular estradiol levels (≥47 pg/mL), (comparable RR=1.39, 95% CI: 0.73–2.65; Pinteraction=0.02). Conclusions We did not observe an overall association between plasma enterolactone and breast cancer risk in a large nested case-control study of US women. However, a significant inverse association was observed among premenopausal women with low follicular estradiol levels, suggesting that enterolactone may be important in a low estrogen environment. This should be confirmed in future studies. PMID:23760859

Prevalence of Hyperkalemia in Diabetic and Non-Diabetic Patients with Chronic Kidney Disease: A Nested Case-Control Study.

PubMed

Loutradis, Charalampos; Tolika, Panagiota; Skodra, Alexandra; Avdelidou, Afroditi; Sarafidis, Pantelis A

2015-01-01

Hyperkalemia is a potentially life-threatening disorder, usually complicating chronic kidney disease (CKD). Factors superimposed to reduced renal function are further elevating hyperkalemia risk, but their contribution is not fully elucidated. This study aimed to compare the prevalence of hyperkalemia in diabetic and non-diabetic patients with CKD. This is a nested case-control study of 180 type-2 diabetic and 180 non-diabetic patients with CKD followed in a Nephrology outpatient clinic, matched for gender, age and estimated glomerular filtration rate. Type-1 diabetes or end-stage renal disease patients were excluded. Prevalence of hyperkalemia was defined as potassium >5 mEq/l or use of sodium polystyrene sulfonate, and further by potassium >5, ≥5.2 and ≥5.5 mEq/l. It was calculated in both groups in whole and CKD stages separately. Univariate and multivariate logistic regression analysis were conducted to identify factors associated with hyperkalemia. The prevalence of hyperkalemia was higher in diabetic CKD patients (27.2 vs. 20%, p = 0.107) and remained around 30% higher with all secondary definitions used, but never reached statistical significance. In Stage 2, no difference was noted (8.7 vs. 17.4%, p = 0.665); in Stage 3, it was significantly higher in diabetics (28.6 vs. 17.5%, p = 0.036); and in Stage 4, it was equally high in both groups (35.5 vs. 32.3%, p = 0.788). In multivariate analysis, Stage 4 CKD (OR 4.535, 95% CI 1.561-13.173), use of angiotensin-converting enzyme inhibitors (ACEIs; OR 2.228, 95% CI 1.254-3.958) and smoking (OR 2.254, 95% CI 1.218-4.171) were independently associated with hyperkalemia. Diabetes mellitus was found to elevate the prevalence of hyperkalemia only in CKD Stage 3 patients (moderately impaired renal function). Advanced CKD at Stage 4 and ACEIs are major determinants of hyperkalemia occurrence. © 2015 S. Karger AG, Basel.

Inverse association between cancer and Alzheimer's disease: results from the Framingham Heart Study.

PubMed

Driver, Jane A; Beiser, Alexa; Au, Rhoda; Kreger, Bernard E; Splansky, Greta Lee; Kurth, Tobias; Kiel, Douglas P; Lu, Kun Ping; Seshadri, Sudha; Wolf, Phillip A

2012-03-12

To relate cancer since entry into the Framingham Heart Study with the risk of incident Alzheimer's disease and to estimate the risk of incident cancer among participants with and without Alzheimer's disease. Community based prospective cohort study; nested age and sex matched case-control study. Framingham Heart Study, USA. 1278 participants with and without a history of cancer who were aged 65 or more and free of dementia at baseline (1986-90). Hazard ratios and 95% confidence intervals for the risks of Alzheimer's disease and cancer. Over a mean follow-up of 10 years, 221 cases of probable Alzheimer's disease were diagnosed. Cancer survivors had a lower risk of probable Alzheimer's disease (hazard ratio 0.67, 95% confidence interval 0.47 to 0.97), adjusted for age, sex, and smoking. The risk was lower among survivors of smoking related cancers (0.26, 0.08 to 0.82) than among survivors of non-smoking related cancers (0.82, 0.57 to 1.19). In contrast with their decreased risk of Alzheimer's disease, survivors of smoking related cancer had a substantially increased risk of stroke (2.18, 1.29 to 3.68). In the nested case-control analysis, participants with probable Alzheimer's disease had a lower risk of subsequent cancer (0.39, 0.26 to 0.58) than reference participants, as did participants with any Alzheimer's disease (0.38) and any dementia (0.44). Cancer survivors had a lower risk of Alzheimer's disease than those without cancer, and patients with Alzheimer's disease had a lower risk of incident cancer. The risk of Alzheimer's disease was lowest in survivors of smoking related cancers, and was not primarily explained by survival bias. This pattern for cancer is similar to that seen in Parkinson's disease and suggests an inverse association between cancer and neurodegeneration.

Mission and Safety Critical (MASC): An EVACS simulation with nested transactions

NASA Technical Reports Server (NTRS)

Auty, David; Atkinson, Colin; Randall, Charlie

1992-01-01

The Extra-Vehicular Activity Control System (EVACS) Simulation with Nested Transactions, a recent effort of the MISSION Kernel Team, is documented. The EVACS simulation is a simulation of some aspects of the Extra-Vehicular Activity Control System, in particular, just the selection of communication frequencies. The simulation is a tool to explore mission and safety critical (MASC) applications. For the purpose of this effort, its current definition is quite narrow serving only as a starting point for prototyping purposes. (Note that EVACS itself has been supplanted in a larger scenario of a lunar outpost with astronauts and a lunar rover). The frequency selection scenario was modified to embed its processing in nested transactions. Again as a first step, only two aspects of transaction support were implemented in this prototype: architecture and state recovery. Issues of concurrency and distribution are yet to be addressed.

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.

Cohort mortality study of North American industrial sand workers. II. Case-referent analysis of lung cancer and silicosis deaths.

PubMed

Hughes, J M; Weill, H; Rando, R J; Shi, R; McDonald, A D; McDonald, J C

2001-04-01

A cohort mortality study of 2670 men in nine North American industrial sand plants resulted in 83 deaths from lung cancer 20 or more years after hire (standardized mortality ratio 139) and 37 deaths from silicosis (including seven from silico-tuberculosis). The lung cancer excess was unrelated to duration of employment and not found in all plants. The primary aim was to determine whether lung cancer risk among these employees was related to quantitative estimates of crystalline silica exposure, after allowance for cigarette smoking. A secondary aim was to do the same for silicosis mortality, partly as a means of validating the estimated levels of exposure. A nested case-referent study was undertaken with cases matched with up to two controls on plant, age and date of first employment from men who survived the case. Exposures were estimated by linking work histories to a job-exposure matrix, undertaken separately. Cigarette smoking information was obtained from medical records and other sources, blind as to case-control status. Matched statistical analyses were conducted using conditional logistic regression. Odds ratios for silicosis mortality were significantly related to cumulative silica exposures and tended to a relationship with category of average crystalline silica concentration, but inconsistently with length of employment. After accounting for a strong effect of cigarette smoking, odds ratios for lung cancer were related to cumulative crystalline silica exposure and to average silica concentration, but not to length of employment. These findings support a causal relationship between lung cancer and quartz exposure after allowance for cigarette smoking, in the absence of cristobalite or other known occupational carcinogens.

Increasing Sun Protection in Winter Outdoor Recreation

PubMed Central

Walkosz, Barbara J.; Buller, David B.; Andersen, Peter A.; Scott, Michael D.; Dignan, Mark B.; Cutter, Gary R.; Maloy, Julie A.

2009-01-01

Background Unprotected and excessive exposure to ultraviolet radiation (UVR) is the primary risk factor for skin cancer. Design A pair-matched, group-randomized, pre-test/post-test, quasi-experimental design, with ski resorts as the unit of randomization, tested the effectiveness of Go Sun Smart, a multi-channel skin cancer prevention program. Independent samples of guests were taken at baseline (2001) and follow-up (2002); data were analyzed in 2006. Setting and Participants A total of 6516 adult guests at 26 ski resorts in the western U.S. and Canada were recruited, consented, and interviewed on chairlifts. This study was nested within an occupational intervention for ski resort workers. Intervention Ski resorts were pair-matched and randomized to receive Go Sun Smart, which consisted of print, electronic, visual, and interpersonal skin cancer prevention messages. Main Outcome Measures Sun-protection behaviors, sunburning, recall of sun-protection messages, and the association of message exposure to sun protection. Results The difference in recall of all sun-protection messages, messages on signs and posters, and the Go Sun Smart logo was significant between the intervention and control resorts. Reported use of sun-protection practices was higher by guests at intervention ski areas using more (a higher dose of) Go Sun Smart materials. Intervention-group guests who recalled a sun-safety message were more likely to practice sun safety than intervention-group guests who did not recall a message and control-group guests. Conclusions While the mere implementation of Go Sun Smart did not produce sun-safety improvements, Go Sun Smart appeared to be effective for guests who encountered and remembered it. Many factors can work against message exposure. Signage seemed to produce the greatest increase in exposure to sun-safety messages. PMID:18471586

Plasma Alkylresorcinols, Biomarkers of Whole-Grain Wheat and Rye Intake, and Incidence of Colorectal Cancer

PubMed Central

2014-01-01

Background Few studies have investigated the association between whole-grain intake and colorectal cancer. Because whole-grain intake estimation might be prone to measurement errors, more objective measures (eg, biomarkers) could assist in investigating such associations. Methods The association between alkylresorcinols, biomarkers of whole-grain rye and wheat intake, and colorectal cancer incidence were investigated using prediagnostic plasma samples from colorectal cancer case patients and matched control subjects nested within the European Prospective Investigation into Cancer and Nutrition. We included 1372 incident colorectal cancer case patients and 1372 individual matched control subjects and calculated the incidence rate ratios (IRRs) for overall and anatomical subsites of colorectal cancer using conditional logistic regression adjusted for potential confounders. Regional differences (Scandinavia, the Mediterranean, Central Europe) were also explored. Results High plasma total alkylresorcinol concentration was associated with lower incidence of distal colon cancer; the adjusted incidence rate ratio of distal colon cancer for the highest vs lowest quartile of plasma total alkylresorcinols was 0.48 (95% confidence interval [CI] = 0.28 to 0.83). An inverse association between plasma total alkylresorcinol concentrations and colon cancer was found for Scandinavian participants (IRR per doubling = 0.83; 95% CI = 0.70 to 0.98). However, plasma total alkylresorcinol concentrations were not associated with overall colorectal cancer, proximal colon cancer, or rectal cancer. Plasma alkylresorcinols concentrations were associated with colon and distal colon cancer only in Central Europe and Scandinavia (ie, areas where alkylresorcinol levels were higher). Conclusions High concentrations of plasma alkylresorcinols were associated with a lower incidence of distal colon cancer but not with overall colorectal cancer, proximal colon cancer, and rectal cancer. PMID:24317181

Hemochromatosis (HFE) gene mutations and risk of gastric cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC) study.

PubMed

Agudo, Antonio; Bonet, Catalina; Sala, Núria; Muñoz, Xavier; Aranda, Núria; Fonseca-Nunes, Ana; Clavel-Chapelon, Françoise; Boutron-Ruault, Marie Christine; Vineis, Paolo; Panico, Salvatore; Palli, Domenico; Tumino, Rosario; Grioni, Sara; Quirós, J Ramón; Molina, Esther; Navarro, Carmen; Barricarte, Aurelio; Chamosa, Saioa; Allen, Naomi E; Khaw, Kay-Tee; Bueno-de-Mesquita, H Bas; Siersema, Peter D; Numans, Mattijs E; Trichopoulou, Antonia; Lagiou, Pagona; Trichopoulos, Dimitrios; Kaaks, Rudof; Canzian, Federico; Boeing, Heiner; Meidtner, Karina; Johansson, Mattias; Sund, Malin; Manjer, Jonas; Overvad, Kim; Tjonneland, Anne; Lund, Eiliv; Weiderpass, Elisabete; Jenab, Mazda; Fedirko, Veronika; Offerhaus, G Johan A; Riboli, Elio; González, Carlos A; Jakszyn, Paula

2013-06-01

Hereditary hemochromatosis (HH) is a strong risk factor for hepatocellular cancer, and mutations in the HFE gene associated with HH and iron overload may be related to other tumors, but no studies have been reported for gastric cancer (GC). A nested case-control study was conducted within the European Prospective Investigation into Cancer and Nutrition (EPIC), including 365 incident gastric adenocarcinoma and 1284 controls matched by center, sex, age and date of blood collection. Genotype analysis was performed for two functional polymorphisms (C282Y/rs1800562 and H63D/rs1799945) and seven tagSNPs of the HFE genomic region. Association with all gastric adenocarcinoma, and according to anatomical localization and histological subtype, was assessed by means of the odds ratio (OR) and 95% confidence interval (CI) estimated by unconditional logistic regression adjusted for the matching variables. We observed a significant association for H63D with OR (per rare allele) of 1.32 (CI = 1.03-1.69). In subgroup analyses, the association was stronger for non-cardia anatomical subsite (OR = 1.60, CI = 1.16-2.21) and intestinal histological subtype (OR = 1.82, CI = 1.27-2.62). Among intestinal cases, two tagSNPs (rs1572982 and rs6918586) also showed a significant association that disappeared after adjustment for H63D. No association with tumors located in the cardia or with diffuse subtype was found for any of the nine SNPs analyzed. Our results suggest that H63D variant in HFE gene seems to be associated with GC risk of the non-cardia region and intestinal type, possibly due to its association with iron overload although a role for other mechanisms cannot be entirely ruled out.

Utilization of Health Services Among Adults With Recurrent Clostridium difficile Infection: A 12-Year Population-Based Study.

PubMed

Kuntz, Jennifer L; Baker, Jennifer M; Kipnis, Patricia; Li, Sherian Xu; Liu, Vincent; Xie, Yang; Marcella, Stephen; Escobar, Gabriel J

2017-01-01

BACKGROUND Considerable efforts have been dedicated to developing strategies to prevent and treat recurrent Clostridium difficile infection (rCDI); however, evidence of the impact of rCDI on patient healthcare utilization and outcomes is limited. OBJECTIVE To compare healthcare utilization and 1-year mortality among adults who had rCDI, nonrecurrent CDI, or no CDI. METHODS We performed a nested case-control study among adult Kaiser Foundation Health Plan members from September 1, 2001, through December 31, 2013. We identified CDI through the presence of a positive laboratory test result and divided patients into 3 groups: patients with rCDI, defined as CDI in the 14-57 days after initial CDI; patients with nonrecurrent CDI; and patients who never had CDI. We conducted 3 matched comparisons: (1) rCDI vs no CDI; (2) rCDI vs nonrecurrent CDI; (3) nonrecurrent CDI vs no CDI. We followed patients for 1 year and compared healthcare utilization between groups, after matching patients on age, sex, and comorbidity. RESULTS We found that patients with rCDI consistently have substantially higher levels of healthcare utilization in various settings and greater 1-year mortality risk than both patients who had nonrecurrent CDI and patients who never had CDI. CONCLUSIONS Patients who develop an initial CDI are generally characterized by excess underlying, severe illness and utilization. However, patients with rCDI experience even greater adverse consequences of their disease than patients who do not experience rCDI. Our results further support the need for continued emphasis on identifying and using novel approaches to prevent and treat rCDI. Infect Control Hosp Epidemiol. 2016;1-8.

An experimental test of interspecific competition for red-cockaded woodpecker cavities

Treesearch

Susan C. Loeb; Robert G. Hooper

1997-01-01

To test whether the presence of nest boxes near red-cockaded woodpecker (RCW, Picoides borealis) cavity trees reduced cavity use by other species and improved RCW reproductive success on the Francis Marion National Forest in coastal South Carolina, the authors placed 3 nest bows in each of 62 experimenta1 boxes clusters and designated 61 clusters as controls....

Use of Nested and Real-Time PCR for the Detection of Ceratocystis fagacearum in the Sapwood of Diseased Oak Species in Minnesota

Treesearch

A. Yang; J. Juzwik

2017-01-01

Oak wilt caused by Ceratocystis fagacearum is a significant disease of Quercus spp. in the eastern United States. Early and accurate detection of the pathogen is particularly important when disease control is planned. Nested and real-time polymerase chain reaction (PCR) methods utilizing fungal DNA extracted from sapwood drill...

Predation on Artificial Nests in Hurricane-Created Gaps and Adjacent Forest of the Southern Appalachians

Treesearch

Cathryn H. Greenberg; C. Reed Rossell; David B. Johnson

2002-01-01

Predation rates were compared during three 7-day trials on 742 artificial ground nests located in 10 hurricane-created canopy gaps and IO adjacent closed-canopy controls in the southern Appalachian mountains of North Carolina. White northern bobwhite (Colinus virginianus) eggs were used in trials 1 and 2, but brown-speckled Japanese Quail (...

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

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.

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.

Comparison of loop-mediated isothermal amplification (LAMP) and nested-PCR assay targeting the RE and B1 gene for detection of Toxoplasma gondii in blood samples of children with leukaemia.

PubMed

Fallahi, Shirzad; Seyyed Tabaei, Seyyed Javad; Pournia, Yadollah; Zebardast, Nozhat; Kazemi, Bahram

2014-07-01

Toxoplasmosis diagnosis constitutes an important measure for disease prevention and control. In this paper, a newly described DNA amplification technique, loop-mediated isothermal amplification (LAMP), and nested-PCR targeting the repeated element (RE) and B1 gene, were compared to each other for the detection of Toxoplasma gondii DNA in blood samples of children with leukaemia. One hundred ten blood samples from these patients were analyzed by LAMP and nested-PCR. Out of 50 seropositive samples (IgM+, IgG+), positive results were obtained with 92% and 86% on RE, B1-LAMP and 82% and 68% on RE, B1-nested PCR analyses, respectively. Of the 50 seronegative samples, three, two and one samples were detected positive by RE-LAMP, B1-LAMP and RE-nested PCR assays, respectively, while none were detected positive by B1-nested PCR. None of the 10 IgM-, IgG+ samples was detected positive after testing LAMP and nested-PCR assays in duplicate. This is the first report of a study in which the LAMP method was applied with high sensitivity and efficacy for the diagnosis of T. gonii in blood samples of children with leukaemia. Copyright © 2014 Elsevier Inc. All rights reserved.

Mate loss in winter and mallard reproduction

USGS Publications Warehouse

Lercel, Barbara A.; Kaminski, Richard M.; Cox, Robert R.

1999-01-01

Mallards (Anas platyrhynchos) frequently pair during winter, and duck hunting seasons have been extended until the end of January in several southern states in the Mississippi Flyway. Therefore, we simulated dissolution of pair bonds from natural or hunting mortality by removing mates of wild-strain, captive, yearling female mallards in late January 1996 and early February 1997 to test if mate loss in winter would affect subsequent pair formation and reproductive performance. Most (97%) widowed females paired again. Nesting and incubation frequencies, nest-initiation date, days between first and second nests, and egg mass did not differ (P > 0.126) between widowed and control (i.e., no mate loss experienced) females in 1996 and 1997. In 1997, widowed females laid 1.91 fewer eggs in first nests (P = 0.014) and 3.75 fewer viable eggs in second nests (P = 0.056). Computer simulations with a mallard productivity model (incorporating default parameters [i.e., average environmental conditions]) indicated that the observed decreased clutch size of first nests, fewer viable eggs in second nests, and these factors combined had potential to decrease recruitment rates of yearling female mallards 9%, 12%, and 20%. Our results indicate that winter mate loss could reduce reproductive performance by yearling female mallards in some years. We suggest caution regarding extending duck hunting seasons in winter without concurrent evaluations of harvest and demographics of mallard and other duck populations.

Unconditional or Conditional Logistic Regression Model for Age-Matched Case-Control Data?

PubMed

Kuo, Chia-Ling; Duan, Yinghui; Grady, James

2018-01-01

Matching on demographic variables is commonly used in case-control studies to adjust for confounding at the design stage. There is a presumption that matched data need to be analyzed by matched methods. Conditional logistic regression has become a standard for matched case-control data to tackle the sparse data problem. The sparse data problem, however, may not be a concern for loose-matching data when the matching between cases and controls is not unique, and one case can be matched to other controls without substantially changing the association. Data matched on a few demographic variables are clearly loose-matching data, and we hypothesize that unconditional logistic regression is a proper method to perform. To address the hypothesis, we compare unconditional and conditional logistic regression models by precision in estimates and hypothesis testing using simulated matched case-control data. Our results support our hypothesis; however, the unconditional model is not as robust as the conditional model to the matching distortion that the matching process not only makes cases and controls similar for matching variables but also for the exposure status. When the study design involves other complex features or the computational burden is high, matching in loose-matching data can be ignored for negligible loss in testing and estimation if the distributions of matching variables are not extremely different between cases and controls.

Unconditional or Conditional Logistic Regression Model for Age-Matched Case–Control Data?

PubMed Central

Kuo, Chia-Ling; Duan, Yinghui; Grady, James

2018-01-01

Matching on demographic variables is commonly used in case–control studies to adjust for confounding at the design stage. There is a presumption that matched data need to be analyzed by matched methods. Conditional logistic regression has become a standard for matched case–control data to tackle the sparse data problem. The sparse data problem, however, may not be a concern for loose-matching data when the matching between cases and controls is not unique, and one case can be matched to other controls without substantially changing the association. Data matched on a few demographic variables are clearly loose-matching data, and we hypothesize that unconditional logistic regression is a proper method to perform. To address the hypothesis, we compare unconditional and conditional logistic regression models by precision in estimates and hypothesis testing using simulated matched case–control data. Our results support our hypothesis; however, the unconditional model is not as robust as the conditional model to the matching distortion that the matching process not only makes cases and controls similar for matching variables but also for the exposure status. When the study design involves other complex features or the computational burden is high, matching in loose-matching data can be ignored for negligible loss in testing and estimation if the distributions of matching variables are not extremely different between cases and controls. PMID:29552553

Brood size and its importance for nestling growth in the Biscutate Swift (Streptoprocne biscutata, Aves: Apodidae).

PubMed

Pichorim, M; Monteiro-Filho, E L A

2008-11-01

Many Apodidae, including Streptoprocne biscutata (Sclater, 1866), drop eggs from their nests during incubation. This is interpreted as nest site competition or accident. We provide evidence that egg ejection is deliberate and that this behaviour controls the brood size. Brood sizes were manipulated and nestling growth was measured to test the hypothesis that pairs can regulate brood size during incubation based on current ability to rear nestlings. Natural (control) broods with one, two and three nestlings, and manipulated (experimental) broods reduced to one and increased to two and three young were monitored. Growth rates were measured based on weight, and wing, tail and tarsus lengths of natural and manipulated broods. We compared the slopes of each measure's regression lines of the nestlings of each brood size by t-test. Nestling growth of control nests was similar and relatively little associated with brood size. In broods reduced to one nestling, weight, wing and tail had greater growth rates, and in broods increased to three nestlings growth rates were lower. Weight was most, and tarsus length least influenced by brood size. In general, nestling growth of manipulated nests was inversely proportional to brood size. The results suggest that pairs with larger clutches are in better physical conditions than others. Thus, in experimental broods, pairs are over or under-loaded because feeding activities increase or decrease and these changes affect the growth rate of the nestlings. The present study suggests that egg ejection can control brood size. This behaviour is probably stimulated by physical changes in the adult birds during incubation.

Egg colour matching in an African cuckoo, as revealed by ultraviolet-visible reflectance spectrophotometry.

PubMed Central

Cherry, M I; Bennett, A T

2001-01-01

Despite major differences between human and avian colour vision, previous studies of cuckoo egg mimicry have used human colour vision (or standards based thereon) to assess colour matching. Using ultraviolet-visible reflectance spectrophotometry (300-700 nm), we measured museum collections of eggs of the red-chested cuckoo and its hosts. The first three principal components explained more than 99% of the variance in spectra, and measures of cuckoo host egg similarity derived from these transformations were compared with measures of cuckoo host egg similarity estimated by human observers unaware of the hypotheses we were testing. Monte Carlo methods were used to simulate laying of cuckoo eggs at random in nests. Results showed that host and cuckoo eggs were very highly matched for an ultraviolet versus greenness component, which was not detected by humans. Furthermore, whereas cuckoo and host were dissimilar in achromatic brightness, humans did not detect this difference. Our study thus reveals aspects of cuckoo-host egg colour matching which have hitherto not been described. These results suggest subtleties and complexities in the evolution of host-cuckoo egg mimicry that were not previously suspected. Our results also have the potential to explain the longstanding paradox that some host species accept cuckoo eggs that are non-mimetic to the human eye. PMID:11297172

Risk of nonfatal acute myocardial infarction associated with non-steroidal antiinflammatory drugs, non-narcotic analgesics and other drugs used in osteoarthritis: a nested case-control study.

PubMed

de Abajo, Francisco J; Gil, Miguel J; García Poza, Patricia; Bryant, Verónica; Oliva, Belén; Timoner, Julia; García-Rodríguez, Luis A

2014-11-01

The purpose of this study is to estimate the risk of nonfatal acute myocardial infarction (AMI) associated with traditional NSAIDs (tNSAIDs), non-narcotic analgesics (paracetamol and metamizole), and symptomatic slow-acting drugs in osteoarthritis (SYSADOAs) overall and in different subgroups of patients. We performed a nested case-control study using a Primary Care Database (Base de datos para la Investigación Farmacoepidemiológica en Atención Primaria), over the study period, 2001-2007. We included patients aged 40-90 years, with nonfatal AMI and randomly selected controls matched for age, sex and calendar year. Exposure to drugs was assessed within a 30-day window before the index date. We did not find an association with nonfatal AMI in patients at low-intermediate background cardiovascular risk (odds ratio = 0.92; 95% confidence interval: 0.76-1.12), whereas there was a moderate significant association among those at high risk (1.28; 1.06-1.54) or when tNSAIDs were used for longer than 365 days (1.43; 1.12-1.82). The greatest risk occurred when these two conditions were combined (1.80; 1.26-2.58). The risk varied across individual tNSAIDs, with ibuprofen (0.95; 0.78-1.16) in the lower and aceclofenac (1.59; 1.15-2.19) in the upper part of the range. Low-dose aspirin did not modify the risk profile showed by any of the individual tNSAIDs examined. Paracetamol (0.84; 0.74-0.95), metamizole (1.06; 0.87-1.29) and SYSADOAs (0.68; 0.47-0.99) were not associated with an increased risk overall or in any subgroup of patients. The risk of nonfatal AMI varied with individual tNSAIDs, duration of treatment and background cardiovascular risk. Paracetamol, metamizole and SYSADOAs did not increase the risk in any of the conditions examined. Copyright © 2014 John Wiley & Sons, Ltd.

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.

The ANDROMEDA prospective cohort study: predictive value of combined criteria to tailor breast cancer screening and new opportunities from circulating markers: study protocol.

PubMed

Giordano, Livia; Gallo, Federica; Petracci, Elisabetta; Chiorino, Giovanna; Segnan, Nereo

2017-11-22

In recent years growing interest has been posed on alternative ways to screen women for breast cancer involving different imaging techniques or adjusting screening interval by breast cancer risk estimates. A new research area is studying circulating microRNAs as molecular biomarkers potentially useful for non invasive early detection together with the analysis of single-nucleotide polymorphisms (SNPs). The Andromeda study is a prospective cohort study on women attending breast cancer screening in a northern Italian area. The aims of the study are: 1) to define appropriate women risk-based stratifications for personalized screening considering different factors (reproductive, family and biopsy history, breast density, lifestyle habits); 2) to evaluate the diagnostic accuracy of selected circulating microRNAs in a case-control study nested within the above mentioned cohort. About 21,000 women aged 46-67 years compliant to screening mammography are expected to be enrolled. At enrolment, information on well-known breast cancer risk factors and life-styles habits are collected through self-admistered questionnaires. Information on breast density and anthropometric measurements (height, weight, body composition, and waist circumference) are recorded. In addition, women are requested to provide a blood sample for serum, plasma and buffy-coat storing for subsequent molecular analyses within the nested case-control study. This investigation will be performed on approximately 233 cases (screen-detected) and 699 matched controls to evaluate SNPs and circulating microRNAs. The whole study will last three years and the cohort will be followed up for ten years to observe the onset of new breast cancer cases. Nowadays women undergo the same screening protocol, independently of their breast density and their individual risk to develop breast cancer. New criteria to better stratify women in risk groups could enable the screening strategies to target high-risk women while reducing interventions in those at low-risk. In this frame the present study will contribute in identifying the feasibility and impact of implementing personalized breast cancer screening. NCT02618538 (retrospectively registered on 27-11-2015.).

Are Metabolic Signatures Mediating the Relationship between Lifestyle Factors and Hepatocellular Carcinoma Risk? Results from a Nested Case-Control Study in EPIC.

PubMed

Assi, Nada; Thomas, Duncan C; Leitzmann, Michael; Stepien, Magdalena; Chajès, Véronique; Philip, Thierry; Vineis, Paolo; Bamia, Christina; Boutron-Ruault, Marie-Christine; Sandanger, Torkjel M; Molinuevo, Amaia; Boshuizen, Hendriek C; Sundkvist, Anneli; Kühn, Tilman; Travis, Ruth C; Overvad, Kim; Riboli, Elio; Gunter, Marc J; Scalbert, Augustin; Jenab, Mazda; Ferrari, Pietro; Viallon, Vivian

2018-05-01

Background: The "meeting-in-the-middle" (MITM) is a principle to identify exposure biomarkers that are also predictors of disease. The MITM statistical framework was applied in a nested case-control study of hepatocellular carcinoma (HCC) within European Prospective Investigation into Cancer and Nutrition (EPIC), where healthy lifestyle index (HLI) variables were related to targeted serum metabolites. Methods: Lifestyle and targeted metabolomic data were available from 147 incident HCC cases and 147 matched controls. Partial least squares analysis related 7 lifestyle variables from a modified HLI to a set of 132 serum-measured metabolites and a liver function score. Mediation analysis evaluated whether metabolic profiles mediated the relationship between each lifestyle exposure and HCC risk. Results: Exposure-related metabolic signatures were identified. Particularly, the body mass index (BMI)-associated metabolic component was positively related to glutamic acid, tyrosine, PC aaC38:3, and liver function score and negatively to lysoPC aC17:0 and aC18:2. The lifetime alcohol-specific signature had negative loadings on sphingomyelins (SM C16:1, C18:1, SM(OH) C14:1, C16:1 and C22:2). Both exposures were associated with increased HCC with total effects (TE) = 1.23 (95% confidence interval = 0.93-1.62) and 1.40 (1.14-1.72), respectively, for BMI and alcohol consumption. Both metabolic signatures mediated the association between BMI and lifetime alcohol consumption and HCC with natural indirect effects, respectively, equal to 1.56 (1.24-1.96) and 1.09 (1.03-1.15), accounting for a proportion mediated of 100% and 24%. Conclusions: In a refined MITM framework, relevant metabolic signatures were identified as mediators in the relationship between lifestyle exposures and HCC risk. Impact: The understanding of the biological basis for the relationship between modifiable exposures and cancer would pave avenues for clinical and public health interventions on metabolic mediators. Cancer Epidemiol Biomarkers Prev; 27(5); 531-40. ©2018 AACR . ©2018 American Association for Cancer Research.

Why are there more arboreal ant species in primary than in secondary tropical forests?

PubMed

Klimes, Petr; Idigel, Cliffson; Rimandai, Maling; Fayle, Tom M; Janda, Milan; Weiblen, George D; Novotny, Vojtech

2012-09-01

1. Species diversity of arboreal arthropods tends to increase during rainforest succession so that primary forest communities comprise more species than those from secondary vegetation, but it is not well understood why. Primary forests differ from secondary forests in a wide array of factors whose relative impacts on arthropod diversity have not yet been quantified. 2. We assessed the effects of succession-related determinants on a keystone ecological group, arboreal ants, by conducting a complete census of 1332 ant nests from all trees with diameter at breast height ≥ 5 cm occurring within two (unreplicated) 0·32-ha plots, one in primary and one in secondary lowland forest in New Guinea. Specifically, we used a novel rarefaction-based approach to match number, size distribution and taxonomic structure of trees in primary forest communities to those in secondary forest and compared the resulting numbers of ant species. 3. In total, we recorded 80 nesting ant species from 389 trees in primary forest but only 42 species from 295 trees in secondary forest. The two habitats did not differ in the mean number of ant species per tree or in the relationship between ant diversity and tree size. However, the between-tree similarity of ant communities was higher in secondary forest than in primary forest, as was the between-tree nest site similarity, suggesting that secondary trees were more uniform in providing nesting microhabitats. 4. Using our rarefaction method, the difference in ant species richness between two forest types was partitioned according to the effects of higher tree density (22·6%), larger tree size (15·5%) and higher taxonomic diversity of trees (14·3%) in primary than in secondary forest. The remaining difference (47·6%) was because of higher beta diversity of ant communities between primary forest trees. In contrast, difference in nest density was explained solely by difference in tree density. 5. Our study shows that reduction in plant taxonomic diversity in secondary forests is not the main driver of the reduction in canopy ant species richness. We suggest that the majority of arboreal species losses in secondary tropical forests are attributable to simpler vegetation structure, combined with lower turnover of nesting microhabitats between trees. © 2012 The Authors. Journal of Animal Ecology © 2012 British Ecological Society.

Nickel Allergy Is a Risk Factor for Endometriosis: An 11-Year Population-Based Nested Case-Control Study.

PubMed

Yuk, Jin-Sung; Shin, Jong Seung; Shin, Ji-Yeon; Oh, Eunsuk; Kim, Hyunmee; Park, Won I

2015-01-01

A cross-sectional study has reported that nickel allergy is associated with endometriosis. However, causal studies of this association are limited. The objective of this study was to compare the prevalence of nickel allergy in women with and without endometriosis. We used a National Health Insurance Service (NHIS) sample cohort dataset that included approximately 1 million individuals from South Korea; the data were obtained between January 01, 2002, and December 31, 2013. We selected the endometriosis group according to diagnosis code (N80.X), surgery codes, and drug codes during the years 2009~2013. The controls were randomly matched to the endometriosis patients at a ratio of 4:1 by age and socioeconomic status. Patients with nickel allergy were defined in the cohort dataset as those with a simultaneous diagnosis code (L23.0) and patch test code during 2002~2008. In total, 4,985 women were selected from the NHIS cohort database and divided into an endometriosis group (997 women) and a control group (3,988 women). The number of patients with nickel allergy in the endometriosis group was eight (0.8%), and that in the control group was thirteen (0.3%). After adjustment for age and socioeconomic status, the rate of nickel allergy in was higher in the endometriosis group than in the control group [odds ratio: 2.474; 95% confidence interval: 1.023~5.988; p = 0.044]. We found that nickel allergy is a risk factor for endometriosis.

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.

Use of female nest characteristics in the sexual behaviour of male sockeye salmon

USGS Publications Warehouse

Hamon, T.R.; Foote, C.J.; Brown, G.S.

1999-01-01

On three island beaches in Iliamna Lake, Alaska, large numbers of male sockeye salmon gathered and spawned in artificial excavations that mimicked a female's nest immediately prior to spawning, while apparently ignoring the control site. The number of males attracted was correlated positively with changes in the operational sex ratio. In contrast, on the mainland beach examined, no reaction to the artificial nests was apparent. The results are discussed in terms of mate searching behaviour by males, the duration of the spawning period, and associated selection pressures on males to use characteristics of their environment that provide information on availability of females.

Response of nesting northern goshawks to logging truck noise in northern Arizona

Treesearch

Teryl G. Grubb; Larry L. Pater; Angela E. Gatto; David K. Delaney

2013-01-01

We recorded 94 sound-response events at 3 adult-occupied northern goshawk (Accipiter gentilis) nests 78 m, 143 m, and 167m from the nearest United States Forest Service maintenance level 3, improved gravel road on the Kaibab Plateau in northern Arizona. During 4 test sessions on 7, 8, 10, and 11 June 2010, we recorded 60 experimentally controlled logging trucks; 30 non...

Endogenous steroid hormone levels in early pregnancy and risk of testicular cancer in the offspring: a nested case-referent study.

PubMed

Holl, Katsiaryna; Lundin, Eva; Surcel, Heljä-Marja; Grankvist, Kjell; Koskela, Pentti; Dillner, Joakim; Hallmans, Göran; Wadell, Göran; Olafsdottir, Gudridur H; Ogmundsdottir, Helga M; Pukkala, Eero; Lehtinen, Matti; Stattin, Pär; Lukanova, Annekatrin

2009-06-15

According to the leading hypothesis on testicular cancer (TC) etiology exposure to a specific pattern of steroid hormones in utero, in particular, to high levels of estrogens and low levels of androgens is the major determinant of TC risk in the offspring. We performed a case-referent study nested within Finnish, Swedish and Icelandic maternity cohorts exploiting early pregnancy serum samples to evaluate the role of maternal endogenous steroid hormones with regard to the risk of TC. TC cases and referents were aged between 0 and 25 years. For each case-index mother pair, three or four matched referent-referent mother pairs were identified using national population registries. First trimester or early second trimester sera were retrieved from the index mothers of 73 TC cases and 286 matched referent mothers, and were tested for dehydroepiandrosterone sulfate (DHEAS), androstenedione, testosterone, estradiol, estrone, and sex hormone binding globulin (SHBG). Offspring of mothers with high DHEAS levels had a significantly decreased risk of TC (OR for highest vs. lowest DHEAS quartile, 0.18 (95% CI 0.06-0.58). In contrast, offspring of mothers with high androstenedione levels had an increased risk of TC (OR 4.1; 95% CI 1.2-12.0). High maternal total estradiol level also tended to be associated with an increased risk of TC in the offspring (OR 32; 95% CI 0.98-1,090). We report the first direct evidence that interplay of maternal steroid hormones in the early pregnancy is important in the etiology of TC in the offspring. Copyright 2008 UICC.

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.

Effectiveness of screening colonoscopy in reducing the risk of death from right and left colon cancer: a large community-based study.

PubMed

Doubeni, Chyke A; Corley, Douglas A; Quinn, Virginia P; Jensen, Christopher D; Zauber, Ann G; Goodman, Michael; Johnson, Jill R; Mehta, Shivan J; Becerra, Tracy A; Zhao, Wei K; Schottinger, Joanne; Doria-Rose, V Paul; Levin, Theodore R; Weiss, Noel S; Fletcher, Robert H

2018-02-01

Screening colonoscopy's effectiveness in reducing colorectal cancer mortality risk in community populations is unclear, particularly for right-colon cancers, leading to recommendations against its use for screening in some countries. This study aimed to determine whether, among average-risk people, receipt of screening colonoscopy reduces the risk of dying from both right-colon and left-colon/rectal cancers. We conducted a nested case-control study with incidence-density matching in screening-eligible Kaiser Permanente members. Patients who were 55-90 years old on their colorectal cancer death date during 2006-2012 were matched on diagnosis (reference) date to controls on age, sex, health plan enrolment duration and geographical region. We excluded patients at increased colorectal cancer risk, or with prior colorectal cancer diagnosis or colectomy. The association between screening colonoscopy receipt in the 10-year period before the reference date and colorectal cancer death risk was evaluated while accounting for other screening exposures. We analysed 1747 patients who died from colorectal cancer and 3460 colorectal cancer-free controls. Compared with no endoscopic screening, receipt of a screening colonoscopy was associated with a 67% reduction in the risk of death from any colorectal cancer (adjusted OR (aOR)=0.33, 95% CI 0.21 to 0.52). By cancer location, screening colonoscopy was associated with a 65% reduction in risk of death for right-colon cancers (aOR=0.35, CI 0.18 to 0.65) and a 75% reduction for left-colon/rectal cancers (aOR=0.25, CI 0.12 to 0.53). Screening colonoscopy was associated with a substantial and comparably decreased mortality risk for both right-sided and left-sided cancers within a large community-based population. 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/.

Urine phyto-oestrogen metabolites are not significantly associated with risk of type 2 diabetes: the Singapore Chinese health study.

PubMed

Talaei, Mohammad; Lee, Bee L; Ong, Choon N; van Dam, Rob M; Yuan, Jian M; Koh, Woon P; Pan, An

2016-05-01

We evaluated the relationship between urine concentrations of phyto-oestrogens (isoflavones and lignans) and risk of incident type 2 diabetes in middle-aged and elderly Chinese residing in Singapore. Urine metabolites of isoflavones and lignans were assayed by HPLC among 564 diabetes cases and 564 matched controls in a case-control study nested within the Singapore Chinese Health Study cohort. Participants were free of diagnosed diabetes, CVD and cancer at morning urine collections during 1999-2004. Cases were participants who reported to have physician-diagnosed diabetes at follow-up visits during 2006-2010, whereas controls were randomly selected among those who remained free of diabetes and were matched to the index cases by age, sex, dialect group and date of urine collection. Conditional logistic regression models were used to calculate OR and 95 % CI with adjustment for potential confounders. The mean age of the participants at the time of urine collection was 59·8 years, and the average interval between urine collection and diabetes diagnosis was 4·0 years. The multivariate-adjusted OR for diabetes were 1·00 (reference), 0·76 (95 % CI 0·52, 1·11), 0·78 (95 % CI 0·53, 1·14) and 0·79 (95 % CI 0·54, 1·15) across quartiles of urine isoflavones (P for trend=0·54), and were 1·00 (reference), 0·87 (95 % CI 0·60, 1·27), 1·10 (95 % CI 0·77, 1·56) and 0·93 (95 % CI 0·63, 1·37) for lignans (P for trend=0·93). The results were similar in men and women, as well as for individual metabolites of isoflavones (genistein, daidzein, glycitin and equol) or lignans (enterodiol and enterolactone). The present study did not find a significant association between urine phyto-oestrogen metabolites and risk of type 2 diabetes in Chinese adults.