Epstein-Barr Virus and Gastric Cancer Risk: A Meta-analysis With Meta-regression of Case-control Studies.

PubMed

Bae, Jong-Myon; Kim, Eun Hee

2016-03-01

Research on how the risk of gastric cancer increases with Epstein-Barr virus (EBV) infection is lacking. In a systematic review that investigated studies published until September 2014, the authors did not calculate the summary odds ratio (SOR) due to heterogeneity across studies. Therefore, we include here additional studies published until October 2015 and conduct a meta-analysis with meta-regression that controls for the heterogeneity among studies. Using the studies selected in the previously published systematic review, we formulated lists of references, cited articles, and related articles provided by PubMed. From the lists, only case-control studies that detected EBV in tissue samples were selected. In order to control for the heterogeneity among studies, subgroup analysis and meta-regression were performed. In the 33 case-control results with adjacent non-cancer tissue, the total number of test samples in the case and control groups was 5280 and 4962, respectively. In the 14 case-control results with normal tissue, the total number of test samples in case and control groups was 1393 and 945, respectively. Upon meta-regression, the type of control tissue was found to be a statistically significant variable with regard to heterogeneity. When the control tissue was normal tissue of healthy individuals, the SOR was 3.41 (95% CI, 1.78 to 6.51; I-squared, 65.5%). The results of the present study support the argument that EBV infection increases the risk of gastric cancer. In the future, age-matched and sex-matched case-control studies should be conducted.

Methods to control for unmeasured confounding in pharmacoepidemiology: an overview.

PubMed

Uddin, Md Jamal; Groenwold, Rolf H H; Ali, Mohammed Sanni; de Boer, Anthonius; Roes, Kit C B; Chowdhury, Muhammad A B; Klungel, Olaf H

2016-06-01

Background Unmeasured confounding is one of the principal problems in pharmacoepidemiologic studies. Several methods have been proposed to detect or control for unmeasured confounding either at the study design phase or the data analysis phase. Aim of the Review To provide an overview of commonly used methods to detect or control for unmeasured confounding and to provide recommendations for proper application in pharmacoepidemiology. Methods/Results Methods to control for unmeasured confounding in the design phase of a study are case only designs (e.g., case-crossover, case-time control, self-controlled case series) and the prior event rate ratio adjustment method. Methods that can be applied in the data analysis phase include, negative control method, perturbation variable method, instrumental variable methods, sensitivity analysis, and ecological analysis. A separate group of methods are those in which additional information on confounders is collected from a substudy. The latter group includes external adjustment, propensity score calibration, two-stage sampling, and multiple imputation. Conclusion As the performance and application of the methods to handle unmeasured confounding may differ across studies and across databases, we stress the importance of using both statistical evidence and substantial clinical knowledge for interpretation of the study results.

Meta-analysis of expression and function of neprilysin in Alzheimer's disease.

PubMed

Zhang, Huifeng; Liu, Dan; Wang, Yixing; Huang, Huanhuan; Zhao, Yujia; Zhou, Hui

2017-09-14

Neprilysin (NEP) is one of the most important Aβ-degrading enzymes, and its expression and activity in Alzheimer's brain have been widely reported, but the results remain debatable. Thus, the meta-analysis was performed to elucidate the role of NEP in Alzheimer's disease (AD). The relevant case-control or cohort studies were retrieved according to our inclusion/exclusion criteria. Six studies with 123 controls and 141 AD cases, seven studies with 102 controls and 90 AD cases, and four studies with 93 controls and 132 AD cases were included in meta-analysis of NEP's protein, mRNA, and enzyme activity respectively. We conducted Meta regression to detect the sources of heterogeneity and further performed cumulative meta-analysis or subgroup analysis. Our meta-analysis revealed a significantly lower level of NEP mRNA (SMD=-0.44, 95%CI: -0.87, -0.00, p=0.049) in AD cases than in non-AD cases, and such pattern was not altered over time in the cumulative meta-analysis. However, the decrease of NEP protein (SMD=-0.18, 95%CI: -0.62, 0.25) and enzyme activity (SMD=-0.35, 95%CI: -1.03, 0.32) in AD cases did not pass the significance check, while the cumulative meta-analysis by average age showed the pooled effect became insignificant as adding the studies with younger subjects, which indicates that the protein expression and enzyme activity of NEP in the cortex are affected by age. Therefore, the present meta-analysis suggests the need of further investigation of roles of NEP in AD pathogenesis and treatment. Copyright © 2017 Elsevier B.V. All rights reserved.

Vitamin C Intake and Pancreatic Cancer Risk: A Meta-Analysis of Published Case-Control and Cohort Studies.

PubMed

Hua, Yong-Fei; Wang, Gao-Qing; Jiang, Wei; Huang, Jing; Chen, Guo-Chong; Lu, Cai-De

2016-01-01

Observational studies inconsistently reported the relationship between vitamin C intake and risk of pancreatic cancer. We conducted a meta-analysis of published case-control and cohort studies to quantify the association. Potentially eligible studies were found on PubMed and EMBASE databases through May 31, 2015. A random-effects model was assigned to compute summary point estimates with corresponding 95% confidence intervals (CIs). Subgroup and meta-regression analyses were also performed to explore sources of heterogeneity. Our final analyses included 20 observational studies comprising nearly 5 thousand cases of pancreatic cancer. When comparing the highest with the lowest categories of vitamin C intake, the summary odds ratio/relative risk for case-control studies (14 studies), cohort studies (6 studies) and all studies combined was 0.58 (95% CI: 0.52-0.66), 0.93 (95% CI: 0.78-1.11) and 0.66 (95% CI: 0.58-0.75), respectively. The difference in the findings between case-control and cohort studies was statistically significant (P < .001). Possible publication bias was shown in the meta-analysis of case-control studies. There is insufficient evidence to conclude any relationship between vitamin C intake and risk of pancreatic cancer. The strong inverse association observed in case-control studies may be affected by biases (eg, recall and selection biases) that particularly affect case-control studies and/or potential publication bias. Future prospective studies of vitamin C intake and pancreatic cancer are needed.

Meta-analysis in more than 17,900 cases of ischemic stroke reveals a novel association at 12q24.12.

PubMed

Kilarski, Laura L; Achterberg, Sefanja; Devan, William J; Traylor, Matthew; Malik, Rainer; Lindgren, Arne; Pare, Guillame; Sharma, Pankaj; Slowik, Agniesczka; Thijs, Vincent; Walters, Matthew; Worrall, Bradford B; Sale, Michele M; Algra, Ale; Kappelle, L Jaap; Wijmenga, Cisca; Norrving, Bo; Sandling, Johanna K; Rönnblom, Lars; Goris, An; Franke, Andre; Sudlow, Cathie; Rothwell, Peter M; Levi, Christopher; Holliday, Elizabeth G; Fornage, Myriam; Psaty, Bruce; Gretarsdottir, Solveig; Thorsteinsdottir, Unnar; Seshadri, Sudha; Mitchell, Braxton D; Kittner, Steven; Clarke, Robert; Hopewell, Jemma C; Bis, Joshua C; Boncoraglio, Giorgio B; Meschia, James; Ikram, M Arfan; Hansen, Bjorn M; Montaner, Joan; Thorleifsson, Gudmar; Stefanson, Kari; Rosand, Jonathan; de Bakker, Paul I W; Farrall, Martin; Dichgans, Martin; Markus, Hugh S; Bevan, Steve

2014-08-19

To perform a genome-wide association study (GWAS) using the Immunochip array in 3,420 cases of ischemic stroke and 6,821 controls, followed by a meta-analysis with data from more than 14,000 additional ischemic stroke cases. Using the Immunochip, we genotyped 3,420 ischemic stroke cases and 6,821 controls. After imputation we meta-analyzed the results with imputed GWAS data from 3,548 cases and 5,972 controls recruited from the ischemic stroke WTCCC2 study, and with summary statistics from a further 8,480 cases and 56,032 controls in the METASTROKE consortium. A final in silico "look-up" of 2 single nucleotide polymorphisms in 2,522 cases and 1,899 controls was performed. Associations were also examined in 1,088 cases with intracerebral hemorrhage and 1,102 controls. In an overall analysis of 17,970 cases of ischemic stroke and 70,764 controls, we identified a novel association on chromosome 12q24 (rs10744777, odds ratio [OR] 1.10 [1.07-1.13], p = 7.12 × 10(-11)) with ischemic stroke. The association was with all ischemic stroke rather than an individual stroke subtype, with similar effect sizes seen in different stroke subtypes. There was no association with intracerebral hemorrhage (OR 1.03 [0.90-1.17], p = 0.695). Our results show, for the first time, a genetic risk locus associated with ischemic stroke as a whole, rather than in a subtype-specific manner. This finding was not associated with intracerebral hemorrhage. © 2014 American Academy of Neurology.

A Mixed-Method Analysis of Reports on 100 Cases of Improper Prescribing of Controlled Substances

PubMed Central

DuBois, James M.; Chibnall, John T.; Anderson, Emily E.; Eggers, Michelle; Baldwin, Kari; Vasher, Meghan

2017-01-01

Improper prescribing of controlled substances contributes to opioid addictions and deaths by overdose. Studies conducted to-date have largely lacked a theoretical framework and ignored the interaction of individual with environmental factors. We conducted a mixed-method analysis of published reports on 100 cases that occurred in the United States. An average of 17 reports (e.g., from medical boards) per case were coded for 38 dichotomous variables describing the physician, setting, patients, and investigation. A theory on how the case occurred was developed for each case. Explanatory typologies were developed and then validated through hierarchical cluster analysis. Most cases involved physicians who were male (88%), >40 years old (90%), non-board certified (63%), and in small private practices (97%); 54% of cases reported facts about the physician indicative of self-centered personality traits. Three explanatory typologies were validated. Increasing oversight provided by peers and trainees may help prevent improper prescribing of controlled substances. PMID:28663601

Laryngospasm during emergency department ketamine sedation: a case-control study.

PubMed

Green, Steven M; Roback, Mark G; Krauss, Baruch

2010-11-01

The objective of this study was to assess predictors of emergency department (ED) ketamine-associated laryngospasm using case-control techniques. We performed a matched case-control analysis of a sample of 8282 ED ketamine sedations (including 22 occurrences of laryngospasm) assembled from 32 prior published series. We sequentially studied the association of each of 7 clinical variables with laryngospasm by assigning 4 controls to each case while matching for the remaining 6 variables. We then used univariate statistics and conditional logistic regression to analyze the matched sets. We found no statistical association of age, dose, oropharyngeal procedure, underlying physical illness, route, or coadministered anticholinergics with laryngospasm. Coadministered benzodiazepines showed a borderline association in the multivariate but not univariate analysis that was considered anomalous. This case-control analysis of the largest available sample of ED ketamine-associated laryngospasm did not demonstrate evidence of association with age, dose, or other clinical factors. Such laryngospasm seems to be idiosyncratic, and accordingly, clinicians administering ketamine must be prepared for its rapid identification and management. Given no evidence that they decrease the risk of laryngospasm, coadministered anticholinergics seem unnecessary.

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.

Health issues in the Arab American community. Male infertility in Lebanon: a case-controlled study.

PubMed

Kobeissi, Loulou; Inhorn, Marcia C

2007-01-01

The impact of risk factors, such as consanguinity and familial clustering, reproductive infections, traumas, and diseases, lifestyle factors and occupational and war exposures on male infertility, was investigated in a case-controlled study conducted in Lebanon. One-hundred-twenty males and 100 controls of Lebanese, Syrian or Lebanese-Palestinian descents were selected from two in-vitro fertilization (IVF) clinics located in Beirut, Lebanon. All cases suffered from impaired sperm count and function, according to World Health Organization guidelines for semen analysis. Controls were the fertile husbands of infertile women. Data were collected using a semi-structured interview, laboratory blood testing and the results of the most recent semen analysis. Univariate, bivariate and multivariate logistic regression analyses were used for data analysis, along with checks for effect modification and control of confounders. Consanguinity and the familial clustering of male infertility cases, as well as reproductive illnesses and war exposures were independently significant risk factors for male infertility. The odds of having infertility problems in the immediate family were 2.6 times higher in cases than controls. The odds of reproductive illness were 2 times higher in cases than controls. The odds of war exposures were 1.57 times higher in cases than controls. Occupational exposures, such as smoking and caffeine intake, were not shown to be important risk factors. This case-controlled study highlights the importance of investigating the etiology of male infertility in Middle Eastern communities. It suggests the need to expand research on male reproductive health in the Middle East in order to improve the prevention and management of male infertility and other male reproductive health problems.

Exploratory factor analysis of signalment and conformational measurements in Thoroughbred horses with and without recurrent laryngeal neuropathy.

PubMed

McGivney, C L; Gough, K F; McGivney, B A; Farries, G; Hill, E W; Katz, L M

2018-06-23

Conflicting results have been reported for risk factors for recurrent laryngeal neuropathy (RLN) based on resting endoscopic evaluation and comparison of single conformation traits, with many traits correlated to one another. To simplify identification of signalment and conformation traits (i.e. variables) associated with RLN cases and controls diagnosed with exercising overground endoscopy (OGE) using exploratory factor analysis (EFA). Prospective cohort. Pearson's rank correlation was used to establish significance and association between variables collected from n = 188 Thoroughbreds from one stable by observers blinded to OGE results. Exploratory factor analysis was conducted on 9 variables for cases and controls; common elements between variables developed a factor, with variables grouped into 3 factors for cases and controls, respectively. Correlation (loading) between each variable and factor was calculated to rank relationships between variables and cases/controls, with factors retrospectively named based on their underlying correlations with variables. Numerous inter-correlations were present between variables. Most strongly correlated in cases were wither height with body weight (r = 0.70) and ventral neck length (r = 0.68) and in controls body weight with rostral neck circumference (r = 0.58). Wither height (r = 0.61) significantly loaded the top-ranked factor for cases ('height RLN '), explaining 25% of conformational variance. Ventral neck length (r = 0.69) and age (r = 0.57) significantly loaded the second-ranked factor for cases ('neck length RLN '), explaining 16% of conformational variance. Rostral neck circumference (r = 0.86) and body weight (r = 0.6) significantly loaded the top-ranked factor for controls ('body size CON '), explaining 19% of the variance. Wither height (r = 0.84) significantly loaded the second-ranked factor for controls ('height CON '), explaining 13% of the variance. Horses had not reached skeletal maturity. Exploratory factor analysis allowed weightings to be determined for each variable. Wither height was the predominant conformational feature associated with RLN. Exploratory factor analysis confirms aggregated conformational differences exist between RLN cases and controls, suitable for future evaluations. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Association study of Demodex bacteria and facial dermatoses based on DGGE technique.

PubMed

Zhao, YaE; Yang, Fan; Wang, RuiLing; Niu, DongLing; Mu, Xin; Yang, Rui; Hu, Li

2017-03-01

The role of bacteria is unclear in the facial skin lesions caused by Demodex. To shed some light on this issue, we conducted a case-control study comparing cases with facial dermatoses with controls with healthy skin using denaturing gradient gel electrophoresis (DGGE) technique. The bacterial diversity, composition, and principal component were analyzed for Demodex bacteria and the matched facial skin bacteria. The result of mite examination showed that all 33 cases were infected with Demodex folliculorum (D. f), whereas 16 out of the 30 controls were infected with D. f, and the remaining 14 controls were infected with Demodex brevis (D. b). The diversity analysis showed that only evenness index presented statistical difference between mite bacteria and matched skin bacteria in the cases. The composition analysis showed that the DGGE bands of cases and controls were assigned to 12 taxa of 4 phyla, including Proteobacteria (39.37-52.78%), Firmicutes (2.7-26.77%), Actinobacteria (0-5.71%), and Bacteroidetes (0-2.08%). In cases, the proportion of Staphylococcus in Firmicutes was significantly higher than that in D. f controls and D. b controls, while the proportion of Sphingomonas in Proteobacteria was significantly lower than that in D. f controls. The between-group analysis (BGA) showed that all the banding patterns clustered into three groups, namely, D. f cases, D. f controls, and D. b controls. Our study suggests that the bacteria in Demodex should come from the matched facial skin bacteria. Proteobacteria and Firmicutes are the two main taxa. The increase of Staphylococcus and decrease of Sphingomonas might be associated with the development of facial dermatoses.

Power and sample size for multivariate logistic modeling of unmatched case-control studies.

PubMed

Gail, Mitchell H; Haneuse, Sebastien

2017-01-01

Sample size calculations are needed to design and assess the feasibility of case-control studies. Although such calculations are readily available for simple case-control designs and univariate analyses, there is limited theory and software for multivariate unconditional logistic analysis of case-control data. Here we outline the theory needed to detect scalar exposure effects or scalar interactions while controlling for other covariates in logistic regression. Both analytical and simulation methods are presented, together with links to the corresponding software.

Is diabetes mellitus a risk factor for venous thromboembolism? A systematic review and meta-analysis of case-control and cohort studies.

PubMed

Gariani, Karim; Mavrakanas, Thomas; Combescure, Christophe; Perrier, Arnaud; Marti, Christophe

2016-03-01

Diabetes mellitus is a well-established risk factor for atherosclerotic disease, but its role in the occurrence of venous thromboembolism (VTE) has not been elucidated. We conducted a meta-analysis of published cohort and case-control studies to assess whether diabetes mellitus is a risk factor for VTE. We systematically searched MEDLINE and EMBASE for case-control and prospective cohort studies assessing association between the risk of venous thromboembolism and diabetes. Odds ratios (OR) from case-control studies were combined while for prospective studies hazard ratios (HR) were combined. Models with random effects were used. Meta-analyses were conducted separately for raw and adjusted measures of association. 24 studies were identified including 10 cohort studies (274,501 patients) and 14 case-control studies (1,157,086 patients). Meta-analysis of the prospective cohort studies demonstrated a significant association between diabetes and VTE (HR 1.60; 95% CI 1.35 to 1.89). This association was no longer present after analysis of multi-adjusted HRs (HR 1.10; 95% CI 0.77 to 1.56). Meta-analysis of case-control studies showed a significant association between diabetes and VTE (OR 1.57; 95%CI 1.17 to 2.12), but this association was no longer present when adjusted ORs were used (OR 1.18; 95%CI 0.89 to 1.56). The increased risk of VTE associated with diabetes mainly results from confounders rather than an intrinsic effect of diabetes on venous thrombotic risk. Therefore, no specific recommendations should apply for the management of diabetic patients at risk for VTE. Copyright © 2015 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.

[Application of nested case-control study on safe evaluation of post-marketing traditional Chinese medicine injection].

PubMed

Xiao, Ying; Zhao, Yubin; Xie, Yanming

2011-10-01

The nested case-control study design (or the case-control in a cohort study) is described here as a new study design used in safe evaluation of post-marketing traditional Chinese medicine injection. In the nested case-control study, cases of a disease that occur in a defined cohort are identified and, for each, a specified number of matched controls is selected from among those in the cohort who have not developed the disease by the time of disease occurrence in the case. For many research questions, the nested case-control design potentially offers impressive reductions in costs and efforts of data collection and analysis compared with the full cohort approach, with relatively minor loss in statistical efficiency. The nested case-control design is particularly advantageous for studies in safe evaluation of post-marketing traditional Chinese medicine injection. Some examples of the application of nested case-control study were given.

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

PubMed Central

Saneei, Parvane; Willett, Walter; Esmaillzadeh, Ahmad

2015-01-01

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

Is probabilistic bias analysis approximately Bayesian?

PubMed Central

MacLehose, Richard F.; Gustafson, Paul

2011-01-01

Case-control studies are particularly susceptible to differential exposure misclassification when exposure status is determined following incident case status. Probabilistic bias analysis methods have been developed as ways to adjust standard effect estimates based on the sensitivity and specificity of exposure misclassification. The iterative sampling method advocated in probabilistic bias analysis bears a distinct resemblance to a Bayesian adjustment; however, it is not identical. Furthermore, without a formal theoretical framework (Bayesian or frequentist), the results of a probabilistic bias analysis remain somewhat difficult to interpret. We describe, both theoretically and empirically, the extent to which probabilistic bias analysis can be viewed as approximately Bayesian. While the differences between probabilistic bias analysis and Bayesian approaches to misclassification can be substantial, these situations often involve unrealistic prior specifications and are relatively easy to detect. Outside of these special cases, probabilistic bias analysis and Bayesian approaches to exposure misclassification in case-control studies appear to perform equally well. PMID:22157311

Vitamin D receptor gene polymorphisms, serum 25-hydroxyvitamin D levels, and melanoma: UK case-control comparisons and a meta-analysis of published VDR data

PubMed Central

Randerson-Moor, Juliette A.; Taylor, John C.; Elliott, Faye; Chang, Yu-Mei; Beswick, Samantha; Kukalizch, Kairen; Affleck, Paul; Leake, Susan; Haynes, Sue; Karpavicius, Birute; Marsden, Jerry; Gerry, Edwina; Bale, Linda; Bertram, Chandra; Field, Helen; Barth, Julian; dos Santos Silva, Isabel; Swerdlow, Anthony; Kanetsky, Peter A.; Barrett, Jennifer H.; Bishop, D. Timothy; Bishop, Julia A. Newton

2009-01-01

We have carried out melanoma case-control comparisons for six vitamin D receptor (VDR) gene single nucleotide polymorphisms (SNPs) and serum 25-hydroxyvitamin D3 levels in order to investigate the role of vitamin D in melanoma susceptibility. There was no significant evidence of an association between any VDR SNP and risk in 1028 population-ascertained cases and 402 controls from Leeds, UK. In a second Leeds case-control study (299 cases and 560 controls) the FokI T allele was associated with increased melanoma risk (OR 1.42, 95% CI 1.06-1.91, p=0.02). In a meta-analysis in conjunction with published data from other smaller data sets (total 3769 cases and 3636 controls), the FokI T allele was associated with increased melanoma risk (odds ratio (OR) 1.19, 95% confidence interval (CI) 1.05-1.35), and the BsmI A allele was associated with a reduced risk (OR 0.81, 95% CI 0.72-0.92), in each instance under a parsimonious dominant model. In the first Leeds case-control comparison cases were more likely to have a higher body mass index (BMI) than controls (p=0.007 for linear trend). There was no evidence of a case-control difference in serum 25-hydroxyvitamin D3 levels. In 1043 incident cases from the first Leeds case-control study, a single estimation of serum 25-hydroxyvitamin D3 level taken at recruitment was inversely correlated with Breslow thickness (p=0.03 for linear trend). These data provide evidence to support the view that vitamin D and VDR may have a small but potentially important role in melanoma susceptibility, and putatively a greater role in disease progression. PMID:19615888

A performance analysis method for distributed real-time robotic systems: A case study of remote teleoperation

NASA Technical Reports Server (NTRS)

Lefebvre, D. R.; Sanderson, A. C.

1994-01-01

Robot coordination and control systems for remote teleoperation applications are by necessity implemented on distributed computers. Modeling and performance analysis of these distributed robotic systems is difficult, but important for economic system design. Performance analysis methods originally developed for conventional distributed computer systems are often unsatisfactory for evaluating real-time systems. The paper introduces a formal model of distributed robotic control systems; and a performance analysis method, based on scheduling theory, which can handle concurrent hard-real-time response specifications. Use of the method is illustrated by a case of remote teleoperation which assesses the effect of communication delays and the allocation of robot control functions on control system hardware requirements.

Birth Weight and Acute Childhood Leukemia: A Meta-analysis of Observational Studies

DTIC Science & Technology

2005-03-22

22 MAR 2005 2. REPORT TYPE 3. DATES COVERED - 4. TITLE AND SUBTITLE Birth Weight and Acute Childhood Leukemia: A Meta - analysis of Observational...and to quantify the strength of the relationships. We conducted a meta - analysis of nine case-control studies (published between 1991 and 2004...Based on a meta - analysis of only three case-control studies (published between 1997 and 2004) involving over 700 children with AML and over 1,900

Cyclin D1 G870A polymorphism and breast cancer risk: a meta-analysis comprising 9,911 cases and 11,171 controls.

PubMed

Sergentanis, Theodoros N; Economopoulos, Konstantinos P

2011-11-01

Cyclin D1 represents a key molecule in the regulation of cell cycle. CCND1 G870A (rs603965) polymorphism has drawn considerable attention as the A allele may generate a variant splice product with possible oncogenic actions. A meta-analysis examining the association between CCND1 G870A polymorphism and breast cancer risk was performed. Separate analyses on Caucasian and Chinese populations were also implemented. Eligible articles were identified for the period up to July 2010. Pooled odds ratios (OR) were appropriately derived from fixed-effects or random-effects models. Sensitivity analysis excluding studies whose genotype frequencies in controls significantly deviated from Hardy-Weinberg Equilibrium (HWE) was performed. Nine case-control studies on Caucasians (7,304 cases and 8,149 controls) and four case-control studies on Chinese (2,607 cases and 3,022 controls) were eligible. At the overall analysis the A allele seemed to be associated with elevated breast cancer risk; the effect seemed to be confined to homozygous carriers (pooled OR = 1.091, 95% CI: 1.008-1.179, P = 0.030, fixed effects) as heterozygous carriers did not exhibit significantly elevated breast cancer risk. No statistically significant associations were demonstrated in Caucasians. On the other hand, Chinese AA carriers exhibited marginally elevated breast cancer risk (pooled OR = 1.144, 95% CI: 0.984-1.329, P = 0.080, fixed effects). Nevertheless, the controls in two out of the four Chinese studies deviated from HWE. In conclusion, this meta-analysis suggests that the A allele of the CCND1 G870A polymorphism may confer additional breast cancer risk when it comes to homozygosity and Chinese populations. The need for additional, methodologically sound studies on Chinese populations seems warranted.

Long term outcome of neonatal meningitis

PubMed Central

Stevens, J; Eames, M; Kent, A; Halket, S; Holt, D; Harvey, D

2003-01-01

Objectives: To quantify long term impairment after neonatal meningitis. Design: Longitudinal case-control study over 9–10 years. Subjects and methods: A total of 111 children who had suffered neonatal meningitis were seen and compared with 113 matched controls from their birth hospital and 49 controls from general practices. Assessments included the WISC IIIUK , movement assessment battery for children (mABC), audiometry, vision testing, and social and medical data. Statistical analysis was by multiple regression, analysis of variance, and χ2 tests. Results: Some 10.8% of cases had a severe and 9% a moderate overall outcome compared with 0% and 1.8% for the hospital controls. The mean intelligence quotient (IQ) of the cases (88.8) was significantly less than that of the hospital controls (99.4) or the GP controls (99.6) . The mABC score was significantly worse for the cases (7.08) than the hospital (5) or GP (4) controls. Some 3.6% of cases had sensorineural hearing loss, 2.7% had persisting hydrocephalus; no controls did. Some 5.4% of cases and 1.7% of hospital controls had treatment for seizures. Conclusions: Severe neurodisability and milder motor and psychometric impairment result from neonatal meningitis. Both clinical follow up and comprehensive developmental assessment are needed after this disease. PMID:12719389

The risk of acute liver injury among users of antibiotic medications: a comparison of case-only studies.

PubMed

Brauer, Ruth; Ruigómez, Ana; Klungel, Olaf; Reynolds, Robert; Feudjo Tepie, Maurille; Smeeth, Liam; Douglas, Ian

2016-03-01

The aims of this study were two-fold: (i) to investigate the effect of exposure to antibiotic agents on the risk of acute liver injury using a self-controlled case series and case-crossover study and (ii) to compare the results between the case-only studies. For the self-controlled case series study relative incidence ratios (IRR) were calculated by dividing the rate of acute liver injury experienced during patients' periods of exposure to antibiotics to patients' rate of events during non-exposed time using conditional Poisson regression. For the case-crossover analysis we calculated Odds Ratios (OR) using conditional logistic regression by comparing exposure during 14- and 30-day risk windows with exposure during control moments. Using the self-controlled case series approach, the IRR was highest during the first 7 days after receipt of a prescription (10.01, 95% CI 6.59-15.18). Omitting post-exposure washout periods lowered the IRR to 7.2. The highest estimate in the case-crossover analysis was found when two 30-day control periods 1 year prior to the 30-day ALI risk period were retained in the analysis: OR = 6.5 (95% CI, 3.95-10.71). The lowest estimate was found when exposure in the 14-day risk period was compared to exposure in four consecutive 14-day control periods immediately prior to the risk period (OR = 3.05, 95% CI, 2.06-4.53). An increased relative risk of acute liver injury was consistently observed using both self-controlled case series and case-crossover designs. Case-only designs can be used as a viable alternative study design to study the risk of acute liver injury, albeit with some limitations. © 2015 The Authors Pharmacoepidemiology and Drug Safety Published by John Wiley & Sons Ltd.

Evaluating psychiatric case-control studies using the STROBE (STrengthening the Reporting of OBservational Studies in Epidemiology) statement.

PubMed

Goi, Pedro Domingues; Goi, Julia Domingues; Cordini, Kariny Larissa; Ceresér, Keila Mendes; Rocha, Neusa Sica da

2014-01-01

Case-control studies are important in developing clinical and public health knowledge. The STROBE statement (STrengthening the Reporting of OBservational Studies in Epidemiology) was developed to establish a checklist of items that should be included in articles reporting observational studies. Our aim was to analyze whether the psychiatric case-control articles published in Brazilian journals with CAPES Qualis rating B1/B2 in 2009 conformed with the STROBE statement. Descriptive study on psychiatric papers published in Brazilian journals, within the Postgraduate Medical Program on Psychiatry, at Universidade Federal do Rio Grande do Sul. All psychiatric case-control studies from Brazilian Qualis B1/B2 journals of psychiatry, neurology and public health in 2009 were analyzed. The four most specific items of the STROBE statement were used to evaluate whether these studies fitted within the case-control parameters: 1) selection of cases and controls; 2) controlling for bias; 3) statistical analysis; and 4) presentation of results. Sixteen case-control studies were identified, of which eleven (68.75%) were in psychiatry-focused journals. From analysis using the STROBE statement, all of the articles conformed with item 1; two (12.5%) completely conformed with item 2; none completely conformed with item 3; and only three (18.8%) conformed with item 4. The case-control studies analyzed here did not completely conform with the four STROBE statement items for case-control design. In view of the inadequate methodology of the published studies, these findings justify focusing on research and methodology and expanding the investigations on adherence of studies to their designs.

Genome-wide Association Study of Obsessive-Compulsive Disorder

PubMed Central

Stewart, S Evelyn; Yu, Dongmei; Scharf, Jeremiah M; Neale, Benjamin M; Fagerness, Jesen A; Mathews, Carol A; Arnold, Paul D; Evans, Patrick D; Gamazon, Eric R; Osiecki, Lisa; McGrath, Lauren; Haddad, Stephen; Crane, Jacquelyn; Hezel, Dianne; Illman, Cornelia; Mayerfeld, Catherine; Konkashbaev, Anuar; Liu, Chunyu; Pluzhnikov, Anna; Tikhomirov, Anna; Edlund, Christopher K; Rauch, Scott L; Moessner, Rainald; Falkai, Peter; Maier, Wolfgang; Ruhrmann, Stephan; Grabe, Hans-Jörgen; Lennertz, Leonard; Wagner, Michael; Bellodi, Laura; Cavallini, Maria Cristina; Richter, Margaret A; Cook, Edwin H; Kennedy, James L; Rosenberg, David; Stein, Dan J; Hemmings, Sian MJ; Lochner, Christine; Azzam, Amin; Chavira, Denise A; Fournier, Eduardo; Garrido, Helena; Sheppard, Brooke; Umaña, Paul; Murphy, Dennis L; Wendland, Jens R; Veenstra-VanderWeele, Jeremy; Denys, Damiaan; Blom, Rianne; Deforce, Dieter; Van Nieuwerburgh, Filip; Westenberg, Herman GM; Walitza, Susanne; Egberts, Karin; Renner, Tobias; Miguel, Euripedes Constantino; Cappi, Carolina; Hounie, Ana G; Conceição do Rosário, Maria; Sampaio, Aline S; Vallada, Homero; Nicolini, Humberto; Lanzagorta, Nuria; Camarena, Beatriz; Delorme, Richard; Leboyer, Marion; Pato, Carlos N; Pato, Michele T; Voyiaziakis, Emanuel; Heutink, Peter; Cath, Danielle C; Posthuma, Danielle; Smit, Jan H; Samuels, Jack; Bienvenu, O Joseph; Cullen, Bernadette; Fyer, Abby J; Grados, Marco A; Greenberg, Benjamin D; McCracken, James T; Riddle, Mark A; Wang, Ying; Coric, Vladimir; Leckman, James F; Bloch, Michael; Pittenger, Christopher; Eapen, Valsamma; Black, Donald W; Ophoff, Roel A; Strengman, Eric; Cusi, Daniele; Turiel, Maurizio; Frau, Francesca; Macciardi, Fabio; Gibbs, J Raphael; Cookson, Mark R; Singleton, Andrew; Hardy, John; Crenshaw, Andrew T; Parkin, Melissa A; Mirel, Daniel B; Conti, David V; Purcell, Shaun; Nestadt, Gerald; Hanna, Gregory L; Jenike, Michael A; Knowles, James A; Cox, Nancy; Pauls, David L

2014-01-01

Obsessive-compulsive disorder (OCD) is a common, debilitating neuropsychiatric illness with complex genetic etiology. The International OCD Foundation Genetics Collaborative (IOCDF-GC) is a multi-national collaboration established to discover the genetic variation predisposing to OCD. A set of individuals affected with DSM-IV OCD, a subset of their parents, and unselected controls, were genotyped with several different Illumina SNP microarrays. After extensive data cleaning, 1,465 cases, 5,557 ancestry-matched controls and 400 complete trios remained, with a common set of 469,410 autosomal and 9,657 X-chromosome SNPs. Ancestry-stratified case-control association analyses were conducted for three genetically-defined subpopulations and combined in two meta-analyses, with and without the trio-based analysis. In the case-control analysis, the lowest two p-values were located within DLGAP1 (p=2.49×10-6 and p=3.44×10-6), a member of the neuronal postsynaptic density complex. In the trio analysis, rs6131295, near BTBD3, exceeded the genome-wide significance threshold with a p-value=3.84 × 10-8. However, when trios were meta-analyzed with the combined case-control samples, the p-value for this variant was 3.62×10-5, losing genome-wide significance. Although no SNPs were identified to be associated with OCD at a genome-wide significant level in the combined trio-case-control sample, a significant enrichment of methylation-QTLs (p<0.001) and frontal lobe eQTLs (p=0.001) was observed within the top-ranked SNPs (p<0.01) from the trio-case-control analysis, suggesting these top signals may have a broad role in gene expression in the brain, and possibly in the etiology of OCD. PMID:22889921

Hunting stability analysis of high-speed train bogie under the frame lateral vibration active control

NASA Astrophysics Data System (ADS)

Yao, Yuan; Wu, Guosong; Sardahi, Yousef; Sun, Jian-Qiao

2018-02-01

In this paper, we study a multi-objective optimal design of three different frame vibration control configurations and compare their performances in improving the lateral stability of a high-speed train bogie. The existence of the time-delay in the control system and its impact on the bogie hunting stability are also investigated. The continuous time approximation method is used to approximate the time-delay system dynamics and then the root locus curves of the system before and after applying control are depicted. The analysis results show that the three control cases could improve the bogie hunting stability effectively. But the root locus of low- frequency hunting mode of bogie which determinates the system critical speed is different, thus affecting the system stability with the increasing of speed. Based on the stability analysis at different bogie dynamics parameters, the robustness of the control case (1) is the strongest. However, the case (2) is more suitable for the dynamic performance requirements of bogie. For the case (1), the time-delay over 10 ms may lead to instability of the control system which will affect the bogie hunting stability seriously. For the case (2) and (3), the increasing time-delay reduces the hunting stability gradually over the high-speed range. At a certain speed, such as 200 km/h, an appropriate time-delay is favourable to the bogie hunting stability. The mechanism is proposed according to the root locus analysis of time-delay system. At last, the nonlinear bifurcation characteristics of the bogie control system are studied by the numerical integration methods to verify the effects of these active control configurations and the delay on the bogie hunting stability.

Can statistic adjustment of OR minimize the potential confounding bias for meta-analysis of case-control study? A secondary data analysis.

PubMed

Liu, Tianyi; Nie, Xiaolu; Wu, Zehao; Zhang, Ying; Feng, Guoshuang; Cai, Siyu; Lv, Yaqi; Peng, Xiaoxia

2017-12-29

Different confounder adjustment strategies were used to estimate odds ratios (ORs) in case-control study, i.e. how many confounders original studies adjusted and what the variables are. This secondary data analysis is aimed to detect whether there are potential biases caused by difference of confounding factor adjustment strategies in case-control study, and whether such bias would impact the summary effect size of meta-analysis. We included all meta-analyses that focused on the association between breast cancer and passive smoking among non-smoking women, as well as each original case-control studies included in these meta-analyses. The relative deviations (RDs) of each original study were calculated to detect how magnitude the adjustment would impact the estimation of ORs, compared with crude ORs. At the same time, a scatter diagram was sketched to describe the distribution of adjusted ORs with different number of adjusted confounders. Substantial inconsistency existed in meta-analysis of case-control studies, which would influence the precision of the summary effect size. First, mixed unadjusted and adjusted ORs were used to combine individual OR in majority of meta-analysis. Second, original studies with different adjustment strategies of confounders were combined, i.e. the number of adjusted confounders and different factors being adjusted in each original study. Third, adjustment did not make the effect size of original studies trend to constringency, which suggested that model fitting might have failed to correct the systematic error caused by confounding. The heterogeneity of confounder adjustment strategies in case-control studies may lead to further bias for summary effect size in meta-analyses, especially for weak or medium associations so that the direction of causal inference would be even reversed. Therefore, further methodological researches are needed, referring to the assessment of confounder adjustment strategies, as well as how to take this kind of bias into consideration when drawing conclusion based on summary estimation of meta-analyses.

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.

Meta-analysis of thirty-two case-control and two ecological radon studies of lung cancer.

PubMed

Dobrzynski, Ludwik; Fornalski, Krzysztof W; Reszczynska, Joanna

2018-03-01

A re-analysis has been carried out of thirty-two case-control and two ecological studies concerning the influence of radon, a radioactive gas, on the risk of lung cancer. Three mathematically simplest dose-response relationships (models) were tested: constant (zero health effect), linear, and parabolic (linear-quadratic). Health effect end-points reported in the analysed studies are odds ratios or relative risk ratios, related either to morbidity or mortality. In our preliminary analysis, we show that the results of dose-response fitting are qualitatively (within uncertainties, given as error bars) the same, whichever of these health effect end-points are applied. Therefore, we deemed it reasonable to aggregate all response data into the so-called Relative Health Factor and jointly analysed such mixed data, to obtain better statistical power. In the second part of our analysis, robust Bayesian and classical methods of analysis were applied to this combined dataset. In this part of our analysis, we selected different subranges of radon concentrations. In view of substantial differences between the methodology used by the authors of case-control and ecological studies, the mathematical relationships (models) were applied mainly to the thirty-two case-control studies. The degree to which the two ecological studies, analysed separately, affect the overall results when combined with the thirty-two case-control studies, has also been evaluated. In all, as a result of our meta-analysis of the combined cohort, we conclude that the analysed data concerning radon concentrations below ~1000 Bq/m3 (~20 mSv/year of effective dose to the whole body) do not support the thesis that radon may be a cause of any statistically significant increase in lung cancer incidence.

Platelet aggregation inhibitors, vitamin K antagonists and risk of subarachnoid hemorrhage.

PubMed

Risselada, R; Straatman, H; van Kooten, F; Dippel, D W J; van der Lugt, A; Niessen, W J; Firouzian, A; Herings, R M C; Sturkenboom, M C J M

2011-03-01

Use of platelet aggregation inhibitors and vitamin K antagonists has been associated with an increased risk of intracranial hemorrhage (ICH). Whether the use of these antithrombotic drugs is associated with an increased risk of subarachnoid hemorrhage (SAH) remains unclear, especially as confounding by indication might play a role. The aim of the present study was to investigate whether use of platelet aggregation inhibitors or vitamin K antagonists increase the risk of SAH. We applied population-based case-control, case-crossover and case-time-control designs to estimate the risk of SAH while addressing issues both of confounding by indication and time varying exposure within the PHARMO Record Linkage System database. This system includes drug dispensing records from community pharmacies and hospital discharge records of more than 3 million community-dwelling inhabitants in the Netherlands. Patients were considered a case if they were hospitalized for a first SAH (ICD-9-CM code 430) in the period between 1st January 1998 and 31st December 2006. Controls were selected from the source population, matched on age, gender and date of hospitalization. Conditional logistic regression was used to estimate multivariable adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for the risk of SAH during use of platelet aggregation inhibitors or vitamin K antagonists. In the case-crossover and case-time-control designs we selected 11 control periods preceding the index date in successive steps of 1 month in the past. In all, 1004 cases of SAH were identified. In the case-control analysis the adjusted OR for the risk of SAH in current use of platelet aggregation inhibitors was 1.32 (95% CI: 1.02-1.70) and in current use of vitamin K antagonists 1.29 (95% CI: 0.89-1.87) compared with no use. In the case-crossover analysis the ORs for the risk of SAH in current use of platelet aggregation inhibitors and vitamin K antagonists were 1.04 (95% CI: 0.56-1.94) and 2.46 (95% CI: 1.04-5.82), respectively. In the case-time-control analysis the OR for platelet aggregation inhibitors was 0.50 (95% CI: 0.26-0.98) and for vitamin K antagonists 1.98 (95% CI: 0.82-4.76). The use of platelet aggregation inhibitors was not associated with an increased SAH risk; the modest increase observed in the case-control analysis could be as a result of confounding. The use of vitamin K antagonists seemed to be associated with an increased risk of SAH. The increase was most pronounced in the case-crossover analysis and therefore cannot be explained by unmeasured confounding. © 2011 International Society on Thrombosis and Haemostasis.

The Relationship between Serum Lipids and Sudden Sensorineural Hearing Loss: A Systematic Review and Meta-Analysis

PubMed Central

Chang, I Jen; Kang, Chung Jan; Yueh, Chen Yu; Fang, Ku Hao; Yeh, Re Ming; Tsai, Yao Te

2015-01-01

Background Sudden sensorineural hearing loss (SSNHL) is a relatively common condition that is usually of unknown etiology. A number of individual studies have investigated the association between various serum lipids and SSNHL; however, the findings have been inconsistent. In an attempt to obtain more definitive information on the relationship between serum lipids and SSNHL, we carried out a systematic review and meta-analysis. Methods Medline, the Cochrane Library, and EMBASE were searched using the following key words: lipid, cholesterol, triglyceride, fat, serum, blood, sudden hearing loss, hearing loss, hearing disorders. Randomized controlled trials, prospective cohort studies, and retrospective case-control studies involving patients with SSNHL and healthy controls that examined the relationship (reported as odds ratios [OR]) between lipid profiles and SSNHL were included. Primary outcomes were total cholesterol and low-density lipoprotein cholesterol (LDL-C) concentrations. Secondary outcomes were triglyceride, high-density lipoprotein cholesterol, and lipoprotein(a) concentrations. Results A total of 6 case-control studies were included in this systematic review/meta-analysis. The total number of participants ranged from 30 to 250 in the case group and from 43 to 271 in the control group. Meta-analysis revealed no significant difference in total cholesterol levels between the case and control groups (pooled OR = 1.79, 95% confidence interval [CI] = 0.98 to 3.26, P = 0.057). Likewise, meta-analysis revealed no significant difference in LDL-C concentrations between the case and control groups (pooled OR = 1.15, 95% CI = 0.64 to 2.07, P = 0.639). Since there were an insufficient number of studies reporting data for the secondary outcomes, meta-analysis was not possible. Conclusions Our results do not provide evidence for serum lipids being associated with SSNHL, nor do they definitively rule out such an association. Additional studies are needed to ascertain the relationship, or lack thereof, between serum lipids and SSNHL. PMID:25866869

Occupational and environmental scleroderma. Systematic review and meta-analysis.

PubMed

Rubio-Rivas, Manuel; Moreno, Rafael; Corbella, Xavier

2017-03-01

The etiology of systemic sclerosis (SSc) remains unknown; however, several occupational and environmental factors have been implicated. Our objective was to perform a meta-analysis of all studies published on SSc associated with occupational and environmental exposure. The review was undertaken by means of MEDLINE and SCOPUS from 1960 to 2014 and using the terms: "systemic," "scleroderma," or "systemic sclerosis/chemically induced" [MesH]. The Newcastle-Ottawa Scale was used for the qualifying assessment. The inverse variance-weighted method was performed. The meta-analysis of silica exposure included 15 case-control studies [overall OR 2.81 (95%CI 1.86-4.23; p < 0.001)] and 4 cohort studies [overall RR 17.52 (95%CI 5.98-51.37; p < 0.001)]; the meta-analysis of solvents exposure included 13 case-control studies (overall OR 2.00 [95%CI 1.32-3.02; p = 0.001); the meta-analysis of breast implants exposure included 4 case-control studies (overall OR 1.68 (95%CI 1.65-1.71; p < 0.001)) and 6 cohort studies (overall RR 2.13 (95%CI 0.86-5.27; p = 0.10)); the meta-analysis of epoxy resins exposure included 4 case-control studies (overall OR 2.97 (95%CI 2.31-3.83; p < 0.001)), the meta-analysis of pesticides exposure included 3 case-control studies (overall OR 1.02 (95%CI 0.78-1.32; p = 0.90)) and, finally, the meta-analysis of welding fumes exposure included 4 studies (overall OR 1.29 (95%CI 0.44-3.74; p = 0.64)). Not enough studies citing risks related to hair dyes have been published to perform an accurate meta-analysis. Silica and solvents were the two most likely substances related to the pathogenesis of SSc. While silica is involved in particular jobs, solvents are widespread and more people are at risk of having incidental contact with them.

Dietary Cholesterol Intake and Risk of Lung Cancer: A Meta-Analysis.

PubMed

Lin, Xiaojing; Liu, Lingli; Fu, Youyun; Gao, Jing; He, Yunyun; Wu, Yang; Lian, Xuemei

2018-02-08

Multiple epidemiologic studies have evaluated the relationship between dietary cholesterol and lung cancer risk, but the association is controversial and inconclusive. A meta-analysis of case-control studies and cohort studies was conducted to evaluate the relationship between dietary cholesterol intake and lung cancer risk in this study. A relevant literature search up to October 2017 was performed in Web of Science, PubMed, China National Knowledge Infrastructure, Sinomed, and VIP Journal Integration Platform. Ten case-control studies and six cohort studies were included in the meta-analysis, and the risk estimates were pooled using either fixed or random effects models. The case-control studies with a total of 6894 lung cancer cases and 29,736 controls showed that dietary cholesterol intake was positively associated with lung cancer risk (Odds Ratio = 1.70, 95% Confidence Interval: 1.43-2.03). However, there was no evidence of an association between dietary cholesterol intake and risk of lung cancer among the 241,920 participants and 1769 lung cancer cases in the cohort studies (Relative Risk = 1.08, 95% Confidence Interval: 0.94-1.25). Due to inconsistent results from case-control and cohort studies, it is difficult to draw any conclusion regarding the effects of dietary cholesterol intake on lung cancer risk. Carefully designed and well-conducted cohort studies are needed to identify the association between dietary cholesterol and lung cancer risk.

Analysis of case-parent trios at a locus with a deletion allele: association of GSTM1 with autism.

PubMed

Buyske, Steven; Williams, Tanishia A; Mars, Audrey E; Stenroos, Edward S; Ming, Sue X; Wang, Rong; Sreenath, Madhura; Factura, Marivic F; Reddy, Chitra; Lambert, George H; Johnson, William G

2006-02-10

Certain loci on the human genome, such as glutathione S-transferase M1 (GSTM1), do not permit heterozygotes to be reliably determined by commonly used methods. Association of such a locus with a disease is therefore generally tested with a case-control design. When subjects have already been ascertained in a case-parent design however, the question arises as to whether the data can still be used to test disease association at such a locus. A likelihood ratio test was constructed that can be used with a case-parents design but has somewhat less power than a Pearson's chi-squared test that uses a case-control design. The test is illustrated on a novel dataset showing a genotype relative risk near 2 for the homozygous GSTM1 deletion genotype and autism. Although the case-control design will remain the mainstay for a locus with a deletion, the likelihood ratio test will be useful for such a locus analyzed as part of a larger case-parent study design. The likelihood ratio test has the advantage that it can incorporate complete and incomplete case-parent trios as well as independent cases and controls. Both analyses support (p = 0.046 for the proposed test, p = 0.028 for the case-control analysis) an association of the homozygous GSTM1 deletion genotype with autism.

Analysis of case-parent trios at a locus with a deletion allele: association of GSTM1 with autism

PubMed Central

Buyske, Steven; Williams, Tanishia A; Mars, Audrey E; Stenroos, Edward S; Ming, Sue X; Wang, Rong; Sreenath, Madhura; Factura, Marivic F; Reddy, Chitra; Lambert, George H; Johnson, William G

2006-01-01

Background Certain loci on the human genome, such as glutathione S-transferase M1 (GSTM1), do not permit heterozygotes to be reliably determined by commonly used methods. Association of such a locus with a disease is therefore generally tested with a case-control design. When subjects have already been ascertained in a case-parent design however, the question arises as to whether the data can still be used to test disease association at such a locus. Results A likelihood ratio test was constructed that can be used with a case-parents design but has somewhat less power than a Pearson's chi-squared test that uses a case-control design. The test is illustrated on a novel dataset showing a genotype relative risk near 2 for the homozygous GSTM1 deletion genotype and autism. Conclusion Although the case-control design will remain the mainstay for a locus with a deletion, the likelihood ratio test will be useful for such a locus analyzed as part of a larger case-parent study design. The likelihood ratio test has the advantage that it can incorporate complete and incomplete case-parent trios as well as independent cases and controls. Both analyses support (p = 0.046 for the proposed test, p = 0.028 for the case-control analysis) an association of the homozygous GSTM1 deletion genotype with autism. PMID:16472391

Analysis of single nucleotide polymorphisms in case-control studies.

PubMed

Li, Yonghong; Shiffman, Dov; Oberbauer, Rainer

2011-01-01

Single nucleotide polymorphisms (SNPs) are the most common type of genetic variants in the human genome. SNPs are known to modify susceptibility to complex diseases. We describe and discuss methods used to identify SNPs associated with disease in case-control studies. An outline on study population selection, sample collection and genotyping platforms is presented, complemented by SNP selection, data preprocessing and analysis.

Accounting for control mislabeling in case-control biomarker studies.

PubMed

Rantalainen, Mattias; Holmes, Chris C

2011-12-02

In biomarker discovery studies, uncertainty associated with case and control labels is often overlooked. By omitting to take into account label uncertainty, model parameters and the predictive risk can become biased, sometimes severely. The most common situation is when the control set contains an unknown number of undiagnosed, or future, cases. This has a marked impact in situations where the model needs to be well-calibrated, e.g., when the prediction performance of a biomarker panel is evaluated. Failing to account for class label uncertainty may lead to underestimation of classification performance and bias in parameter estimates. This can further impact on meta-analysis for combining evidence from multiple studies. Using a simulation study, we outline how conventional statistical models can be modified to address class label uncertainty leading to well-calibrated prediction performance estimates and reduced bias in meta-analysis. We focus on the problem of mislabeled control subjects in case-control studies, i.e., when some of the control subjects are undiagnosed cases, although the procedures we report are generic. The uncertainty in control status is a particular situation common in biomarker discovery studies in the context of genomic and molecular epidemiology, where control subjects are commonly sampled from the general population with an established expected disease incidence rate.

An outbreak of vancomycin-resistant Enterococcus faecium in an acute care pediatric hospital: Lessons from environmental screening and a case-control study

PubMed Central

Drews, Steven J; Richardson, Susan E; Wray, Rick; Freeman, Renee; Goldman, Carol; Streitenberger, Laurie; Stevens, Derek; Goia, Cristina; Kovach, Danuta; Brophy, Jason; Matlow, Anne G

2008-01-01

BACKGROUND The present study describes a vancomycin-resistant enterococci (VRE) outbreak investigation and a case-control study to identify risk factors for VRE acquisition in a tertiary care pediatric hospital. OBJECTIVE To report an outbreak investigation and a case-control study to identify risk factors for VRE colonization or infection in hospitalized children. METHODS Screening for VRE cases was performed by culture or polymerase chain reaction. A case-control study of VRE-colonized patients was undertaken. Environmental screening was performed using standard culture and susceptibility methods, with pulsed-field gel electrophoresis to determine relationships between VRE isolates. Statistical analysis was performed using SAS version 9.0 (SAS Institute Inc, USA). RESULTS Thirty-four VRE-positive cases were identified on 10 wards between February 28, 2005, and May 27, 2005. Pulsed-field gel electrophoresis analysis confirmed a single outbreak strain that was also isolated from a video game found on one affected ward. Multivariate analysis identified cephalosporin use as the major risk factor for VRE colonization. CONCLUSIONS In the present study outbreak, VRE colonization was significantly associated with cephalosporin use. Because shared recreational items and environmental surfaces may be colonized by VRE, they warrant particular attention in housekeeping protocols, particularly in pediatric institutions. PMID:19412380

Effectiveness of 23-valent pneumococcal polysaccharide vaccine and seasonal influenza vaccine for pneumonia among the elderly - Selection of controls in a case-control study.

PubMed

Kondo, Kyoko; Suzuki, Kanzo; Washio, Masakazu; Ohfuji, Satoko; Fukushima, Wakaba; Maeda, Akiko; Hirota, Yoshio

2017-08-24

We conducted a case-control study to elucidate associations between pneumonia in elderly individuals and 23-valent pneumococcal polysaccharide vaccine (PPSV23) and seasonal influenza vaccine (influenza vaccine). Here, we examined selection of controls in our study using an analytic epidemiology approach. The study period was from October 1, 2009 through September 30, 2014. Cases comprised ≥65-year-old patients newly diagnosed with pneumonia. For every case with pneumonia, two patients with other diseases (one respiratory medicine, one non-respiratory medicine) who were sex-, age-, visit date- and visit hospital-matched were selected as controls. Odds ratios (ORs) and 95% confidence intervals (CIs) of vaccination for pneumonia were calculated using conditional logistic regression model. Similar analyses were also conducted based on the clinical department of controls. Analysis was conducted in 234 cases and 438 controls. Effectiveness of pneumococcal vaccination or influenza vaccination against pneumonia was not detected. Proportions of either vaccination in controls were greater among respiratory medicine (pneumococcal vaccine, 38%; influenza vaccine, 55%) than among non-respiratory medicine (23%; 48%). Analysis using controls restricted to respiratory medicine showed marginally significant effectiveness of pneumococcal vaccination (OR, 0.59; 95%CI, 0.34-1.03; P=0.064) and influenza vaccination (0.64; 0.40-1.04; 0.072). However, this effectiveness might have been overestimated by selection bias of controls, as pneumonia cases are not necessarily respiratory medicine patients. In the analysis using controls restricted to non-respiratory medicine, OR of pneumococcal vaccination for pneumonia was close to 1, presumably because the proportion of pneumococcal vaccination was higher in cases than in controls. Because pneumococcal vaccine was not routinely administered during the study period, differences in recommendations of vaccination by physician in different clinical departments might have greatly affected vaccination proportions. When we select controls, we should consider the background factors (underlying diseases, clinical department, etc.) which affect physicians' recommendation of vaccination. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Considerations for the Systematic Analysis and Use of Single-Case Research

ERIC Educational Resources Information Center

Horner, Robert H.; Swaminathan, Hariharan; Sugai, George; Smolkowski, Keith

2012-01-01

Single-case research designs provide a rigorous research methodology for documenting experimental control. If single-case methods are to gain wider application, however, a need exists to define more clearly (a) the logic of single-case designs, (b) the process and decision rules for visual analysis, and (c) an accepted process for integrating…

Performance analysis and dynamic modeling of a single-spool turbojet engine

NASA Astrophysics Data System (ADS)

Andrei, Irina-Carmen; Toader, Adrian; Stroe, Gabriela; Frunzulica, Florin

2017-01-01

The purposes of modeling and simulation of a turbojet engine are the steady state analysis and transient analysis. From the steady state analysis, which consists in the investigation of the operating, equilibrium regimes and it is based on appropriate modeling describing the operation of a turbojet engine at design and off-design regimes, results the performance analysis, concluded by the engine's operational maps (i.e. the altitude map, velocity map and speed map) and the engine's universal map. The mathematical model that allows the calculation of the design and off-design performances, in case of a single spool turbojet is detailed. An in house code was developed, its calibration was done for the J85 turbojet engine as the test case. The dynamic modeling of the turbojet engine is obtained from the energy balance equations for compressor, combustor and turbine, as the engine's main parts. The transient analysis, which is based on appropriate modeling of engine and its main parts, expresses the dynamic behavior of the turbojet engine, and further, provides details regarding the engine's control. The aim of the dynamic analysis is to determine a control program for the turbojet, based on the results provided by performance analysis. In case of the single-spool turbojet engine, with fixed nozzle geometry, the thrust is controlled by one parameter, which is the fuel flow rate. The design and management of the aircraft engine controls are based on the results of the transient analysis. The construction of the design model is complex, since it is based on both steady-state and transient analysis, further allowing the flight path cycle analysis and optimizations. This paper presents numerical simulations for a single-spool turbojet engine (J85 as test case), with appropriate modeling for steady-state and dynamic analysis.

Longitudinal Analysis of the Premature Infant Intestinal Microbiome Prior to Necrotizing Enterocolitis: A Case-Control Study

PubMed Central

Zhou, Yanjiao; Shan, Gururaj; Sodergren, Erica; Weinstock, George; Walker, W. Allan; Gregory, Katherine E.

2015-01-01

Necrotizing enterocolitis (NEC) is an inflammatory disease of the newborn bowel, primarily affecting premature infants. Early intestinal colonization has been implicated in the pathogenesis of NEC. The objective of this prospective case-control study was to evaluate differences in the intestinal microbiota between infants who developed NEC and unaffected controls prior to disease onset. We conducted longitudinal analysis of the 16S rRNA genes of 312 samples obtained from 12 NEC cases and 26 age-matched controls with a median frequency of 7 samples per subject and median sampling interval of 3 days. We found that the microbiome undergoes dynamic development during the first two months of life with day of life being the major factor contributing to the colonization process. Depending on when the infant was diagnosed with NEC (i.e. early vs. late onset), the pattern of microbial progression was different for cases and controls. The difference in the microbiota was most overt in early onset NEC cases and controls. In proximity to NEC onset, the abundances of Clostridium sensu stricto from Clostridia class were significantly higher in early onset NEC subjects comparing to controls. In late onset NEC, Escherichia/Shigella among Gammaproteobacteria, showed an increasing pattern prior to disease onset, and was significantly higher in cases than controls six days before NEC onset. Cronobacter from Gammaproteobacteria was also significantly higher in late onset NEC cases than controls 1-3 days prior to NEC onset. Thus, the specific infectious agent associated with NEC may vary by the age of infant at disease onset. We found that intravenously administered antibiotics may have an impact on the microbial diversity present in fecal material. Longitudinal analysis at multiple time points was an important strategy utilized in this study, allowing us to appreciate the dynamics of the premature infant intestinal microbiome while approaching NEC at various points. PMID:25741698

Analysis of airframe/engine interactions in integrated flight and propulsion control

NASA Technical Reports Server (NTRS)

Schierman, John D.; Schmidt, David K.

1991-01-01

An analysis framework for the assessment of dynamic cross-coupling between airframe and engine systems from the perspective of integrated flight/propulsion control is presented. This analysis involves to determining the significance of the interactions with respect to deterioration in stability robustness and performance, as well as critical frequency ranges where problems may occur due to these interactions. The analysis illustrated here investigates both the airframe's effects on the engine control loops and the engine's effects on the airframe control loops in two case studies. The second case study involves a multi-input/multi-output analysis of the airframe. Sensitivity studies are performed on critical interactions to examine the degradations in the system's stability robustness and performance. Magnitudes of the interactions required to cause instabilities, as well as the frequencies at which the instabilities occur are recorded. Finally, the analysis framework is expanded to include control laws which contain cross-feeds between the airframe and engine systems.

Polygenic risk score analysis of pathologically confirmed Alzheimer disease.

PubMed

Escott-Price, Valentina; Myers, Amanda J; Huentelman, Matt; Hardy, John

2017-08-01

Previous estimates of the utility of polygenic risk score analysis for the prediction of Alzheimer disease have given area under the curve (AUC) estimates of <80%. However, these have been based on the genetic analysis of clinical case-control series. Here, we apply the same analytic approaches to a pathological case-control series and show a predictive AUC of 84%. We suggest that this analysis has clinical utility and that there is limited room for further improvement using genetic data. Ann Neurol 2017;82:311-314. © 2017 American Neurological Association.

Lung cancer among coal miners, ore miners and quarrymen: smoking-adjusted risk estimates from the synergy pooled analysis of case-control studies.

PubMed

Taeger, Dirk; Pesch, Beate; Kendzia, Benjamin; Behrens, Thomas; Jöckel, Karl-Heinz; Dahmann, Dirk; Siemiatycki, Jack; Kromhout, Hans; Vermeulen, Roel; Peters, Susan; Olsson, Ann; Brüske, Irene; Wichmann, Heinz-Erich; Stücker, Isabelle; Guida, Florence; Tardón, Adonina; Merletti, Franco; Mirabelli, Dario; Richiardi, Lorenzo; Pohlabeln, Hermann; Ahrens, Wolfgang; Landi, Maria Teresa; Caporaso, Neil; Pesatori, Angela Cecilia; Mukeriya, Anush; Szeszenia-Dabrowska, Neonila; Lissowska, Jolanta; Gustavsson, Per; Field, John; Marcus, Michael W; Fabianova, Eleonora; 't Mannetje, Andrea; Pearce, Neil; Rudnai, Peter; Bencko, Vladimir; Janout, Vladimir; Dumitru, Rodica Stanescu; Foretova, Lenka; Forastiere, Francesco; McLaughlin, John; Paul Demers, Paul Demers; Bueno-de-Mesquita, Bas; Schüz, Joachim; Straif, Kurt; Brüning, Thomas

2015-09-01

Working in mines and quarries has been associated with an elevated lung cancer risk but with inconsistent results for coal miners. This study aimed to estimate the smoking-adjusted lung cancer risk among coal miners and compare the risk pattern with lung cancer risks among ore miners and quarrymen. We estimated lung cancer risks of coal and ore miners and quarrymen among 14 251 lung cancer cases and 17 267 controls from the SYNERGY pooled case-control study, controlling for smoking and employment in other at-risk occupations. Ever working as miner or quarryman (690 cases, 436 controls) was associated with an elevated odds ratio (OR) of 1.55 [95% confidence interval (95% CI) 1.34-1.79] for lung cancer. Ore miners (53 cases, 24 controls) had a higher OR (2.34, 95% CI 1.36-4.03) than quarrymen (67 cases, 39 controls; OR 1.92, 95% CI 1.21-3.05) and coal miners (442 cases, 297 controls; OR 1.40, 95% CI 1.18-1.67), but CI overlapped. We did not observe trends by duration of exposure or time since last exposure. This pooled analysis of population-based studies demonstrated an excess lung cancer risk among miners and quarrymen that remained increased after adjustment for detailed smoking history and working in other at-risk occupations. The increase in risk among coal miners were less pronounced than for ore miners or quarrymen.

Meta-analysis identifies a MECOM gene as a novel predisposing factor of osteoporotic fracture

PubMed Central

Hwang, Joo-Yeon; Lee, Seung Hun; Go, Min Jin; Kim, Beom-Jun; Kou, Ikuyo; Ikegawa, Shiro; Guo, Yan; Deng, Hong-Wen; Raychaudhuri, Soumya; Kim, Young Jin; Oh, Ji Hee; Kim, Youngdoe; Moon, Sanghoon; Kim, Dong-Joon; Koo, Heejo; Cha, My-Jung; Lee, Min Hye; Yun, Ji Young; Yoo, Hye-Sook; Kang, Young-Ah; Cho, Eun-Hee; Kim, Sang-Wook; Oh, Ki Won; Kang, Moo II; Son, Ho Young; Kim, Shin-Yoon; Kim, Ghi Su; Han, Bok-Ghee; Cho, Yoon Shin; Cho, Myeong-Chan; Lee, Jong-Young; Koh, Jung-Min

2014-01-01

Background Osteoporotic fracture (OF) as a clinical endpoint is a major complication of osteoporosis. To screen for OF susceptibility genes, we performed a genome-wide association study and carried out de novo replication analysis of an East Asian population. Methods Association was tested using a logistic regression analysis. A meta-analysis was performed on the combined results using effect size and standard errors estimated for each study. Results In a combined meta-analysis of a discovery cohort (288 cases and 1139 controls), three hospital based sets in replication stage I (462 cases and 1745 controls), and an independent ethnic group in replication stage II (369 cases and 560 for controls), we identified a new locus associated with OF (rs784288 in the MECOM gene) that showed genome-wide significance (p=3.59×10−8; OR 1.39). RNA interference revealed that a MECOM knockdown suppresses osteoclastogenesis. Conclusions Our findings provide new insights into the genetic architecture underlying OF in East Asians. PMID:23349225

Complexity analysis of fetal heart rate preceding intrauterine demise.

PubMed

Schnettler, William T; Goldberger, Ary L; Ralston, Steven J; Costa, Madalena

2016-08-01

Visual non-stress test interpretation lacks the optimal specificity and observer-agreement of an ideal screening tool for intrauterine fetal demise (IUFD) syndrome prevention. Computational methods based on traditional heart rate variability have also been of limited value. Complexity analysis probes properties of the dynamics of physiologic signals that are otherwise not accessible and, therefore, might be useful in this context. To explore the association between fetal heart rate (FHR) complexity analysis and subsequent IUFD. Our specific hypothesis is that the complexity of the fetal heart rate dynamics is lower in the IUFD group compared with controls. This case-control study utilized cases of IUFD at a single tertiary-care center among singleton pregnancies with at least 10min of continuous electronic FHR monitoring on at least 2 weekly occasions in the 3 weeks immediately prior to fetal demise. Controls delivered a live singleton beyond 35 weeks' gestation and were matched to cases by gestational age, testing indication, and maternal age in a 3:1 ratio. FHR data was analyzed using the multiscale entropy (MSE) method to derive their complexity index. In addition, pNNx, a measure of short-term heart rate variability, which in adults is ascribable primarily to cardiac vagal tone modulation, was also computed. 211 IUFDs occurred during the 9-year period of review, but only 6 met inclusion criteria. The median gestational age at the time of IUFD was 35.5 weeks. Three controls were matched to each case for a total of 24 subjects, and 87 FHR tracings were included for analysis. The median gestational age at the first fetal heart rate tracing was similar between groups (median [1st-3rd quartiles] weeks: IUFD cases: 34.7 (34.4-36.2); controls: 35.3 (34.4-36.1); p=.94). The median complexity of the cases' tracings was significantly less than the controls' (12.44 [8.9-16.77] vs. 17.82 [15.21-22.17]; p<.0001). Furthermore, the cases' median complexity decreased as gestation advanced whereas the controls' median complexity increased over time. However, this difference was not statistically significant [-0.83 (-2.03 to 0.47) vs. 0.14 (-1.25 to 0.94); p=.62]. The degree of short-term variability of FHR tracings, as measured by the pNN metric, was significantly lower (p<.005) for the controls (1.1 [0.8-1.3]) than the IUFD cases (1.3 [1.1-1.6]). FHR complexity analysis using multiscale entropy analysis may add value to other measures in detecting and monitoring pregnancies at the highest risk for IUFD. The decrease in complexity and short-term variability seen in the IUFD cases may reflect perturbations in neuroautonomic control due to multiple maternal-fetal factors. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Genome-wide association analysis of secondary imaging phenotypes from the Alzheimer's disease neuroimaging initiative study.

PubMed

Zhu, Wensheng; Yuan, Ying; Zhang, Jingwen; Zhou, Fan; Knickmeyer, Rebecca C; Zhu, Hongtu

2017-02-01

The aim of this paper is to systematically evaluate a biased sampling issue associated with genome-wide association analysis (GWAS) of imaging phenotypes for most imaging genetic studies, including the Alzheimer's Disease Neuroimaging Initiative (ADNI). Specifically, the original sampling scheme of these imaging genetic studies is primarily the retrospective case-control design, whereas most existing statistical analyses of these studies ignore such sampling scheme by directly correlating imaging phenotypes (called the secondary traits) with genotype. Although it has been well documented in genetic epidemiology that ignoring the case-control sampling scheme can produce highly biased estimates, and subsequently lead to misleading results and suspicious associations, such findings are not well documented in imaging genetics. We use extensive simulations and a large-scale imaging genetic data analysis of the Alzheimer's Disease Neuroimaging Initiative (ADNI) data to evaluate the effects of the case-control sampling scheme on GWAS results based on some standard statistical methods, such as linear regression methods, while comparing it with several advanced statistical methods that appropriately adjust for the case-control sampling scheme. Copyright © 2016 Elsevier Inc. All rights reserved.

Population specific impact of genetic variants in KCNJ11 gene to type 2 diabetes: a case-control and meta-analysis study.

PubMed

Phani, Nagaraja M; Guddattu, Vasudeva; Bellampalli, Ravishankara; Seenappa, Venu; Adhikari, Prabha; Nagri, Shivashankara K; D Souza, Sydney C; Mundyat, Gopinath P; Satyamoorthy, Kapaettu; Rai, Padmalatha S

2014-01-01

Potassium inwardly rectifying channel, subfamily J, member 11 (KCNJ11) gene have a key role in insulin secretion and is of substantial interest as a candidate gene for type 2 diabetes (T2D). The current work was performed to delineate the genetic influence of KCNJ11 polymorphisms on risk of T2D in South Indian population through case-control association study along with systematic review and meta-analysis. A case-control study of 400 T2D cases and controls of South Indian origin were performed to analyze the association of KCNJ11 polymorphisms (rs5219, rs5215, rs41282930, rs1800467) and copy number variations (CNV) on the risk of T2D. In addition a systematic review and meta-analysis for KCNJ11 rs5219 was conducted in 3,831 cases and 3,543 controls from 5 published reports from South-Asian population by searching various databases. Odds ratio with 95% confidence interval (CI) was used to assess the association strength. Cochran's Q, I2 statistics were used to study heterogeneity between the eligible studies. KCNJ11 rs5215, C-G-C-C haplotype and two loci analysis (rs5219 vs rs1800467) showed a significant association with T2D but CNV analysis did not show significant variation between T2D cases and control subjects. Lower age of disease onset (P = 0.04) and higher body mass index (BMI) (P = 0.04) were associated with rs5219 TT genotype in T2D patients. The meta-analysis of KCNJ11 rs5219 on South Asian population showed no association on susceptibility to T2D with an overall pooled OR = 0.98, 95% CI = 0.83-1.16. Stratification analysis showed East Asian population and global population were associated with T2D when compared to South Asians. KCNJ11 rs5219 is not independently associated with T2D in South-Indian population and our meta-analysis suggests that KCNJ11 polymorphism (rs5219) is associated with risk of T2D in East Asian population and global population but this outcome could not be replicated in South Asian sub groups.

Nested case-control studies: should one break the matching?

PubMed

Borgan, Ørnulf; Keogh, Ruth

2015-10-01

In a nested case-control study, controls are selected for each case from the individuals who are at risk at the time at which the case occurs. We say that the controls are matched on study time. To adjust for possible confounding, it is common to match on other variables as well. The standard analysis of nested case-control data is based on a partial likelihood which compares the covariates of each case to those of its matched controls. It has been suggested that one may break the matching of nested case-control data and analyse them as case-cohort data using an inverse probability weighted (IPW) pseudo likelihood. Further, when some covariates are available for all individuals in the cohort, multiple imputation (MI) makes it possible to use all available data in the cohort. In the paper we review the standard method and the IPW and MI approaches, and compare their performance using simulations that cover a range of scenarios, including one and two endpoints.

Allergies and risk of head and neck cancer: an original study plus meta-analysis.

PubMed

Hsiao, Jenn-Ren; Ou, Chun-Yen; Lo, Hung-I; Huang, Cheng-Chih; Lee, Wei-Ting; Huang, Jehn-Shyun; Chen, Ken-Chung; Wong, Tung-Yiu; Tsai, Sen-Tien; Yen, Chia-Jui; Wu, Yuan-Hua; Hsueh, Wei-Ting; Yang, Ming-Wei; Wu, Shang-Yin; Chang, Jang-Yang; Chang, Kwang-Yu; Lin, Chen-Lin; Wang, Fang-Ting; Wang, Yi-Hui; Weng, Ya-Ling; Yang, Han-Chien; Chang, Jeffrey S

2013-01-01

Although the relationship between allergy and cancer has been investigated extensively, the role of allergy in head and neck cancer (HNC) appears less consistent. It is not clear whether allergies can independently influence the risk of HNC in the presence of known strong environmental risk factors, including consumption of alcohol, betel quid, and cigarette. THE CURRENT PAPER REPORTS RESULTS FROM: 1) an original hospital-based case-control study, which included 252 incident cases of HNC and 236 controls frequency-matched to cases on sex and age; and 2) a meta-analysis combining the results of the current case-control study and 13 previously published studies (9 cohort studies with 727,569 subjects and 550 HNC outcomes and 5 case-control studies with 4,017 HNC cases and 10,928 controls). In the original case-control study, we observed a strong inverse association between allergies and HNC [odds ratio = 0.41, 95% confidence interval (CI): 0.27-0.62]. The meta-analysis also indicated a statistically significant inverse association between HNC and allergies [meta-relative risk (RR) = 0.76, 95% CI: 0.63-0.91], particularly strong for allergic rhinitis (meta-RR = 0.55, 95% CI: 0.40-0.76). In addition, the inverse association between allergies and HNC was observed only among men (meta-RR = 0.67, 95% CI: 0.54-0.84) but not among women (meta-RR = 0.98, 95% CI: 0.81-1.18). These findings suggest that immunity plays an influential role in the risk of HNC. Future studies investigating immune biomarkers, including cytokine profiles and genetic polymorphisms, are warranted to further delineate the relationship between allergies and HNC. Understanding the relationship between allergies and HNC may help devise effective strategies to reduce and treat HNC.

Cell-free fetal DNA concentration in plasma of patients with abnormal uterine artery Doppler waveform and intrauterine growth restriction--a pilot study.

PubMed

Caramelli, Elisabetta; Rizzo, Nicola; Concu, Manuela; Simonazzi, Giuliana; Carinci, Paolo; Bondavalli, Corrado; Bovicelli, Luciano; Farina, Antonio

2003-05-01

To evaluate if an increased amount of fetal DNA concentration can be found in women screened positive for intrauterine growth restriction because of abnormal uterine artery Doppler waveforms. We enrolled eight pregnant women (each bearing a male fetus), with the evidence of abnormal uterine artery Doppler waveforms, and 16 control patients for a case-control study matched for gestational age (1 : 2). Uterine artery Doppler was carried out at 20 to 35 weeks' gestation (median 29). The mean uterine artery resistance index (RI) was subsequently calculated, and a value >0.6 was considered positive for the clinical features of pre-eclampsia. The SRY locus was used to determine the amount of male fetal DNA in the maternal plasma at the time of Doppler analysis. Two controls (normal Doppler) were excluded from the final analysis because they had a pre-term delivery. One case (abnormal Doppler) had evidence of intrauterine growth restriction at the time of enrolment. In four out of eight cases (abnormal Doppler), intrauterine growth restriction was subsequently observed. Multiples of median (MoM) conversion of the fetal DNA values showed an increase of 1.81 times in the cases when compared to the controls. An increase of 2.16 times was instead observed for the cases with a growth-restricted fetus (5 cases out of 8) in comparison with the controls (14 cases). In subjects positive to uterine artery Doppler velocimetry analysis (Doppler analysis for pre-eclampsia screening), the fetal DNA concentration is higher than expected, in the absence of any other clinical feature. Since the increase in fetal DNA seems to be related to the presence or to the future development of intrauterine growth restriction, this paper suggests a possible integration between ultrasound and molecular markers for predicting the disease in some cases. Copyright 2003 John Wiley & Sons, Ltd.

Glycemic index, glycemic load and endometrial cancer risk: results from the Australian National Endometrial Cancer study and an updated systematic review and meta-analysis.

PubMed

Nagle, Christina M; Olsen, Catherine M; Ibiebele, Torukiri I; Spurdle, Amanda B; Webb, Penelope M

2013-03-01

The relationship between habitual consumption of foods with a high glycemic index (GI) and/or a diet with a high glycemic load (GL) and risk of endometrial cancer is uncertain, and relatively few studies have investigated these associations. The objectives of this study were to examine the association between GI/GL and risk of endometrial cancer using data from an Australian population-based case-control study and systematically review all the available evidence to quantify the magnitude of the association using meta-analysis. The case-control study included 1,290 women aged 18-79 years with newly diagnosed, histologically confirmed endometrial cancer and 1,436 population controls. Controls were selected to match the expected Australian state of residence and age distribution (in 5-year bands) of cases. For the systematic review, relevant studies were identified by searching PubMed and Embase databases through to July 2011. Random-effects models were used to calculate the summary risk estimates, overall and dose-response. In our case-control study, we observed a modest positive association between high dietary GI (OR 1.43, 95 % CI 1.11-1.83) and risk of endometrial cancer, but no association with high dietary GL (OR 1.15, 95 % CI 0.90-1.48). For the meta-analysis, we collated information from six cohort and two case-control studies, involving a total of 5,569 cases. The pooled OR for the highest versus the lowest intake category of GI was 1.15 (0.95-1.40); however, there was significant heterogeneity (p 0.004) by study design (RR 1.00 [95 % CI 0.87-1.14] for cohort studies and 1.56 [95 % CI 1.21-2.02] for case-control studies). There was no association in the dose-response meta-analysis of GI (RR per 5 unit/day increment of GI 1.00, 95 % CI 0.97-1.03). GL was positively associated with endometrial cancer. The pooled RR for the highest versus the lowest GL intake was 1.21 (95 % CI 1.09-1.33) and 1.06 (95 % CI 1.01-1.11) per 50 unit/day increment of GL in the dose-response meta-analysis. The pooled results from observational studies, including our case-control results, provide evidence of a modest positive association between high GL, but not GI, and endometrial cancer risk.

Three ADIPOR1 Polymorphisms and Cancer Risk: A Meta-Analysis of Case-Control Studies.

PubMed

Ye, Jiaxiang; Jiang, Li; Wu, Changliang; Liu, Aiqun; Mao, Sufei; Ge, Lianying

2015-01-01

Studies have come to conflicting conclusions about whether polymorphisms in the adiponectin receptor 1 gene (ADIPOR1) are associated with cancer risk. To help resolve this question, we meta-analyzed case-control studies in the literature. PubMed, EMBASE, Cochrane Library, the Chinese Biological Medical Database and the Chinese National Knowledge Infrastructure Database were systematically searched to identify all case-control studies published through February 2015 examining any ADIPOR1 polymorphisms and risk of any type of cancer. Pooled odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were calculated. A total of 13 case-control studies involving 5,750 cases and 6,762 controls were analyzed. Analysis of the entire study population revealed a significant association between rs1342387(G/A) and overall cancer risk using a homozygous model (OR 0.82, 95%CI 0.72 to 0.94), heterozygous model (OR 0.84, 95%CI 0.76 to 0.93), dominant model (OR 0.85, 95%CI 0.75 to 0.97) and allele contrast model (OR 0.88, 95%CI 0.80 to 0.97). However, subgroup analysis showed that this association was significant only for Asians in the case of colorectal cancer. No significant associations were found between rs12733285(C/T) or rs7539542(C/G) and cancer risk, either in analyses of the entire study population or in analyses of subgroups. Our meta-analysis suggests that the ADIPOR1 rs1342387(G/A) polymorphism, but not rs12733285(C/T) or rs7539542(C/G), may be associated with cancer risk, especially risk of colorectal cancer in Asians. Large, well-designed studies are needed to verify our findings.

Androgen receptor CAG repeats length polymorphism and the risk of polycystic ovarian syndrome (PCOS).

PubMed

Rajender, Singh; Carlus, Silas Justin; Bansal, Sandeep Kumar; Negi, Mahendra Pal Singh; Negi, Mahendra Pratap Singh; Sadasivam, Nirmala; Sadasivam, Muthusamy Narayanan; Thangaraj, Kumarasamy

2013-01-01

Polycystic ovarian syndrome (PCOS) refers to an inheritable androgen excess disorder characterized by multiple small follicles located at the ovarian periphery. Hyperandrogenism in PCOS, and inverse correlation between androgen receptor (AR) CAG numbers and AR function, led us to hypothesize that CAG length variations may affect PCOS risk. CAG repeat region of 169 patients recruited following strictly defined Rotterdam (2003) inclusion criteria and that of 175 ethnically similar control samples, were analyzed. We also conducted a meta-analysis on the data taken from published studies, to generate a pooled estimate on 2194 cases and 2242 controls. CAG bi-allelic mean length was between 8.5 and 24.5 (mean = 17.43, SD = 2.43) repeats in the controls and between 11 and 24 (mean = 17.39, SD = 2.29) repeats in the cases, without any significant difference between the two groups. Further, comparison of bi-allelic mean and its frequency distribution in three categories (short, moderate and long alleles) did not show any significant difference between controls and various case subgroups. Frequency distribution of bi-allelic mean in two categories (extreme and moderate alleles) showed over-representation of extreme sized alleles in the cases with marginally significant value (50.3% vs. 61.5%, χ(2) = 4.41; P = 0.036), which turned insignificant upon applying Bonferroni correction for multiple comparisons. X-chromosome inactivation analysis showed no significant difference in the inactivation pattern of CAG alleles or in the comparison of weighed bi-allelic mean between cases and controls. Meta-analysis also showed no significant correlation between CAG length and PCOS risk, except a minor over-representation of short CAG alleles in the cases. CAG bi-allelic mean length did not differ between controls and cases/case sub-groups nor did the allele distribution. Over-representation of short/extreme-sized alleles in the cases may be a chance finding without any true association with PCOS risk.

Descriptive epidemiology and natural history of idiopathic venous thromboembolism in U.S. active duty enlisted personnel, 1998-2007.

PubMed

Freeman, Randall J; Li, Yuanzhang; Niebuhr, David W

2011-05-01

The estimated incidence of idiopathic venous thromboembolism (IVTE) cases in the United States ranges from 24,000 to 282,000/year. This analysis explores the incidence and prevalence of IVTE in the military and if cases experience increased attrition. The Defense Medical Surveillance System was searched for incident IVTE cases from 1998 through 2007. Enlisted cases were each matched to 3 controls. Kaplan-Meier survival analysis and Cox proportional hazard modeling were performed. We matched 463 cases to 1,389 controls. Outpatient IVTE rates have increased markedly from 1998 through 2007. Cases of all-cause attrition risk (0.56 [95% CI = 0.44, 0.72]) and rates were significantly less than controls (p < 0.0001), and cases of medical attrition risk (1.64 [95% CI = 1.13, 2.37]) and rates were significantly higher (p < 0.01). Increasing rates with lower attrition suggests increasing case prevalence. Health care providers must maintain a high index of suspicion for venous thromboembolism to minimize adverse sequelae affecting health, unit readiness, and medical costs.

Relationship between C-Reactive Protein Level and Diabetic Retinopathy: A Systematic Review and Meta-Analysis

PubMed Central

Chen, Song; Duan, Hongtao; Kong, Jiahui; Li, Zedong

2015-01-01

Objectives To date, the relationship between C-reactive protein (CRP) level and diabetic retinopathy (DR) remains controversial. Therefore, a systematic review and meta-analysis was used to reveal the potential relationship between CRP level and DR. Methods A systematic search of PubMed, Embase.com, and Web of Science was performed to identify all comparative studies that compared the CRP level of two groups (case group and control group). We defined that diabetic patients without retinopathy and /or matched healthy persons constituted the control group, and patients with DR were the case group. Results Two cross sectional studies and twenty case control studies including a total of 3679 participants were identified. After pooling the data from all 22 studies, obvious heterogeneity existed between the studies, so a subgroup analysis and sensitivity analysis were performed. Removing the sensitivity studies, the blood CRP levels in the case group were observed to be higher than those in the control group [SMD = 0.22, 95% confidence interval (CI), 0.11–0.34], and the blood CRP levels in the proliferative diabetic retinopathy (PDR) group were also higher than those in the non-proliferative diabetic retinopathy (NPDR) group [SMD = 0.50, 95% CI, 0.30–0.70]. Conclusions The results from this current meta-analysis indicate that the CRP level might be used as a biomarker to determine the severity of DR. PMID:26636823

A case-control study of diesel exhaust exposure and bladder cancer.

PubMed

Wynder, E L; Dieck, G S; Hall, N E; Lahti, H

1985-08-01

The relationship between bladder cancer and employment in occupations involving exposure to diesel exhaust was examined using data from a hospital-based case-control study of men aged 20 to 80 years in 18 hospitals in six U.S. cities, from January 1981 to May 1983. In this analysis, 194 cases and 582 controls were compared according to occupation, smoking history, alcohol and coffee consumption, and various demographic variables. No difference was found in the proportion of bladder cancer cases employed in occupations with exposure to diesel exhaust compared to controls. This relationship did not change after taking smoking habits into account. Bladder cancer cases were significantly more likely to be current smokers of cigarettes than were controls.

Effect of sulfasalazine use on the presence of Pneumocystis organisms in the lung among patients with rheumatoid arthritis: A test-negative design case-control study with PCR tests.

PubMed

Nunokawa, Takahiro; Yokogawa, Naoto; Shimada, Kota; Sugii, Shoji

2018-05-03

To evaluate the effect of sulfasalazine (SSZ) on the presence of Pneumocystis jirovecii (P. jirovecii) in the lungs of rheumatoid arthritis (RA) patients. We retrospectively studied episodes of suspected P. jirovecii pneumonia (PJP) which were examined for P. jirovecii with polymerase chain reaction (PCR). We employed a test negative design case-control study; the cases were episodes of suspected PJP that were positive for PCR, and the controls were episodes of suspected PJP that were negative for PCR. The odds ratio for the positive PCR result associated with SSZ use was estimated by Firth's logistic regression. Between 2003 and 2017, 36 cases and 83 controls were identified. While none of the cases received SSZ before the episode, 18 of the controls received the drug. In the primary analysis involving all the episodes, SSZ use was negatively associated with PCR positivity (adjusted odds ratio, 0.087; confidence interval, <0.001-0.789). The sensitivity analysis, excluding those who received PJP prophylaxis, showed the same association as the primary analysis (adjusted odds ratio 0.085, 95% CI <0.001-0.790). This study demonstrated that SSZ use is associated with the absence of P. jirovecii in the lung, suggesting the preventive efficacy of the drug against PJP.

Hypertension and the risk of endometrial cancer: a systematic review and meta-analysis of case-control and cohort studies.

PubMed

Aune, Dagfinn; Sen, Abhijit; Vatten, Lars J

2017-04-07

A history of hypertension has been associated with increased risk of endometrial cancer in several studies, but the results have not been consistent. We conducted a systematic review and meta-analysis of case-control and cohort studies to clarify the association between hypertension and endometrial cancer risk. PubMed and Embase databases were searched up to 27 th of February 2016. Prospective and case-control studies which reported adjusted relative risk estimates and 95% confidence intervals of endometrial cancer associated with a hypertension diagnosis were included. Summary relative risks were estimated using a random effects model. Nineteen case-control studies and 6 cohort studies were included. The summary RR was 1.61 (95% CI: 1.41-1.85, I 2  = 86%) for all studies, 1.73 (95% CI: 1.45-2.06, I 2  = 89%) for case-control studies and 1.32 (95% CI: 1.12-1.56, I 2  = 47%) for cohort studies. The association between hypertension and endometrial cancer was weaker, but still significant, among studies with adjustment for smoking, BMI, oral contraceptive use, and parity, compared to studies without such adjustment. This meta-analysis suggest an increased risk of endometrial cancer among patients with hypertension, however, further studies with more comprehensive adjustments for confounders are warranted to clarify the association.

Financial statement analysis, internal controls, and audit readiness: Bestpractices for Pakistan army financial management officers

DTIC Science & Technology

2017-06-01

2012). Noland and Metrejean (2013) emphasize the importance of the internal control environment and cite the June 2010 case of a non -existent...NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA MBA PROFESSIONAL REPORT FINANCIAL STATEMENT ANALYSIS, INTERNAL CONTROLS , AND...FINANCIAL STATEMENT ANALYSIS, INTERNAL CONTROLS , AND AUDIT READINESS: BEST PRACTICES FOR PAKISTAN ARMY FINANCIAL MANAGEMENT OFFICERS 5. FUNDING NUMBERS 6

Association between Toll-like receptor 4 Asp299Gly polymorphism and coronary heart disease susceptibility.

PubMed

Wu, B W; Zhu, J; Shi, H M; Jin, B; Wen, Z C

2017-08-07

Published data on the association between Toll-like receptor 4 (TLR4) Asp299Gly polymorphism and coronary heart disease (CHD) susceptibility are inconclusive. To derive a more precise estimation of the relationship, a meta-analysis was performed. English-language studies were identified by searching PubMed and Embase databases (up to November 2016). All epidemiological studies were regarding Caucasians because no TLR4 Asp/Gly and Gly/Gly genotypes have been detected in Asians. A total of 20 case-control studies involving 14,416 cases and 10,764 controls were included in the meta-analysis. Overall, no significant associations were found between TLR4 Asp299Gly polymorphism and CHD susceptibility in the dominant model (OR=0.89; 95%CI=0.74 to 1.06; P=0.20) pooled in the meta-analysis. In the subgroup analysis by CHD, non-significant associations were found in cases compared to controls. When stratified by control source, no significantly decreased risk was found in the additive model or dominant model. The present meta-analysis suggests that the TLR4 Asp299Gly polymorphism was not associated with decreased CHD risk in Caucasians.

FOXO3 variants are beneficial for longevity in Southern Chinese living in the Red River Basin: A case-control study and meta-analysis

PubMed Central

Sun, Liang; Hu, Caiyou; Zheng, Chenguang; Qian, Yu; Liang, Qinghua; Lv, Zeping; Huang, Zezhi; Qi, KeYan; Gong, Huan; Zhang, Zheng; Huang, Jin; Zhou, Qin; Yang, Ze

2015-01-01

Forkhead box class O (FOXO) transcription factors play a crucial role in longevity across species. Several polymorphisms in FOXO3 were previously reported to be associated with human longevity. However, only one Chinese replication study has been performed so far. To verify the role of FOXO3 in southern Chinese in the Red River Basin, a community-based case-control study was conducted, and seven polymorphisms were genotyped in 1336 participants, followed by a meta-analysis of eight case-control studies that included 5327 longevity cases and 4608 controls. In our case-control study, we found rs2802288*A and rs2802292*G were beneficial to longevity after Bonferroni correction (pallele = 0.005, OR = 1.266; pallele = 0.026, OR = 1.207). In addition, in the longevity group, carriers with rs2802288*A and rs2802292*G presented reduced HbA1c (p = 0.001), and homozygotes of rs2802292*GG presented improved HOMA–IR (p = 0.014). The meta-analysis further revealed the overall contribution of rs2802288*A and rs2802292*G to longevity. However, our stratified analysis revealed that rs2802292*G might act more strongly in Asians than Europeans, for enhancement of longevity. In conclusion, our study provides convincing evidence for a significant association between the rs2802288*A and rs2802292*G gene variants in FOXO3 and human longevity, and adds the Southern Chinese in the Red River Basin to the growing number of human replication populations. PMID:25913413

FOXO3 variants are beneficial for longevity in Southern Chinese living in the Red River Basin: A case-control study and meta-analysis.

PubMed

Sun, Liang; Hu, Caiyou; Zheng, Chenguang; Qian, Yu; Liang, Qinghua; Lv, Zeping; Huang, Zezhi; Qi, KeYan; Gong, Huan; Zhang, Zheng; Huang, Jin; Zhou, Qin; Yang, Ze

2015-04-27

Forkhead box class O (FOXO) transcription factors play a crucial role in longevity across species. Several polymorphisms in FOXO3 were previously reported to be associated with human longevity. However, only one Chinese replication study has been performed so far. To verify the role of FOXO3 in southern Chinese in the Red River Basin, a community-based case-control study was conducted, and seven polymorphisms were genotyped in 1336 participants, followed by a meta-analysis of eight case-control studies that included 5327 longevity cases and 4608 controls. In our case-control study, we found rs2802288*A and rs2802292*G were beneficial to longevity after Bonferroni correction (pallele = 0.005, OR = 1.266; pallele = 0.026, OR = 1.207). In addition, in the longevity group, carriers with rs2802288*A and rs2802292*G presented reduced HbA1c (p = 0.001), and homozygotes of rs2802292*GG presented improved HOMA-IR (p = 0.014). The meta-analysis further revealed the overall contribution of rs2802288*A and rs2802292*G to longevity. However, our stratified analysis revealed that rs2802292*G might act more strongly in Asians than Europeans, for enhancement of longevity. In conclusion, our study provides convincing evidence for a significant association between the rs2802288*A and rs2802292*G gene variants in FOXO3 and human longevity, and adds the Southern Chinese in the Red River Basin to the growing number of human replication populations.

Pooled analysis of case-control studies on malignant brain tumours and the use of mobile and cordless phones including living and deceased subjects.

PubMed

Hardell, Lennart; Carlberg, Michael; Hansson Mild, Kjell

2011-05-01

We studied the association between use of mobile and cordless phones and malignant brain tumours. Pooled analysis was performed of two case-control studies on patients with malignant brain tumours diagnosed during 1997-2003 and matched controls alive at the time of study inclusion and one case-control study on deceased patients and controls diagnosed during the same time period. Cases and controls or relatives to deceased subjects were interviewed using a structured questionnaire. Replies were obtained for 1,251 (85%) cases and 2,438 (84%) controls. The risk increased with latency period and cumulative use in hours for both mobile and cordless phones. Highest risk was found for the most common type of glioma, astrocytoma, yielding in the >10 year latency group for mobile phone use odds ratio (OR) = 2.7, 95% confidence interval (CI) = 1.9-3.7 and cordless phone use OR = 1.8, 95% CI = 1.2-2.9. In a separate analysis, these phone types were independent risk factors for glioma. The risk for astrocytoma was highest in the group with first use of a wireless phone before the age of 20; mobile phone use OR = 4.9, 95% CI = 2.2-11, cordless phone use OR = 3.9, 95% CI = 1.7-8.7. In conclusion, an increased risk was found for glioma and use of mobile or cordless phone. The risk increased with latency time and cumulative use in hours and was highest in subjects with first use before the age of 20.

Coffee, decaffeinated coffee, tea and cancer of the colon and rectum: a review of epidemiological studies, 1990-2003.

PubMed

Tavani, Alessandra; La Vecchia, Carlo

2004-10-01

The literature from 1990 to 2003 on the relation between coffee, decaffeinated coffee, tea and colorectal cancer risk has been reviewed. For the relation with coffee, three cohort (517 total cases) and nine case-control studies (7555 cases) analysed colon cancer; three cohort (307 cases) and four case-control studies (2704 cases) rectal cancer; six case-control studies (854 cases) colorectal cancer. For colon cancer most case-control studies found risk estimates below unity; the results are less clear for cohort studies. No relation emerged for rectal cancer. A meta-analysis, including five cohort and twelve case-control studies, reported a pooled relative risk of 0.76 (significant). Any methodological artefact is unlikely to account for the consistent inverse association in different countries and settings. Plausible biological explanations include coffee-related reductions of cholesterol, bile acids and neutral sterol secretion in the colon; antimutagenic properties of selected coffee components; increased colonic motility. Decaffeinated coffee was not related to either colon or rectal cancer in three case-control studies. No overall association between tea and either colon or rectal cancer risk emerged in seven cohort (1756 total cases of colon, 759 of rectal and 60 of colorectal cancer) and 12 case-control studies (8058 cases of colon, 4865 of rectal, 604 of colorectal cancer).

Complexity analysis of human physiological signals based on case studies

NASA Astrophysics Data System (ADS)

Angelova, Maia; Holloway, Philip; Ellis, Jason

2015-04-01

This work focuses on methods for investigation of physiological time series based on complexity analysis. It is a part of a wider programme to determine non-invasive markers for healthy ageing. We consider two case studies investigated with actigraphy: (a) sleep and alternations with insomnia, and (b) ageing effects on mobility patterns. We illustrate, using these case studies, the application of fractal analysis to the investigation of regulation patterns and control, and change of physiological function. In the first case study, fractal analysis techniques were implemented to study the correlations present in sleep actigraphy for individuals suffering from acute insomnia in comparison with healthy controls. The aim was to investigate if complexity analysis can detect the onset of adverse health-related events. The subjects with acute insomnia displayed significantly higher levels of complexity, possibly a result of too much activity in the underlying regulatory systems. The second case study considered mobility patterns during night time and their variations with age. It showed that complexity metrics can identify change in physiological function with ageing. Both studies demonstrated that complexity analysis can be used to investigate markers of health, disease and healthy ageing.

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.

Beta-2 adrenergic receptor (ADRB2) gene polymorphisms and the risk of asthma: a meta-analysis of case-control studies.

PubMed

Liang, Si-Qiao; Chen, Xiao-Li; Deng, Jing-Min; Wei, Xuan; Gong, Chen; Chen, Zhang-Rong; Wang, Zhi-Bo

2014-01-01

A number of studies have assessed the relationship between beta-2 adrenergic receptor (ADRB2) gene polymorphisms and asthma risk. However, the results are inconsistent. A meta-analysis that focused on the association between asthma and all ADRB2 polymorphisms with at least three case-control studies was thus performed. A literature search of the PubMed, Embase, Web of Science, CNKI, and Wangfang databases was conducted. Odds ratios with 95% confidence intervals were used to assess the strength of associations. Arg16Gly, Gln27Glu, Thr164Ile, and Arg19Cys single nucleotide polymorphisms (SNPs) were identified in 46 case-control studies. The results showed that not all of the SNPs were associated with asthma in the overall population. Significant associations were found for the Arg16Gly polymorphism in the South American population via dominant model comparison (OR = 1.754, 95% CI = 1.179-2.609, I2 = 16.9%, studies  = 2, case  = 314, control  = 237) in an analysis stratified by ethnicity. For the Gln27Glu polymorphism, a protective association was found in children via recessive model comparison (OR = 0.566, 95% CI = 0.417-0.769, I2 = 0.0%, studies  = 11, case  = 1693, control  =  502) and homozygote genotype comparison (OR = 0.610, 95% CI = 0.434-0.856, I2 = 0.0%, studies  = 11, case  = 1693, control  = 1502), and in adults via dominant model comparison (OR = 0.864, 95% CI = 0.768-0.971, I2 = 46.9%, n = 18, case  = 3160, control  = 3433). None of the ADRB2 gene polymorphisms were reproducibly associated with a risk of asthma across ethnic groups in the general population.

The -765G>C polymorphism in the cyclooxygenase-2 gene and digestive system cancer: a meta-analysis.

PubMed

Zhao, Fen; Cao, Yue; Zhu, Hong; Huang, Min; Yi, Cheng; Huang, Ying

2014-01-01

Published data regarding associations between the -765G>C polymorphism in cyclooxygenase-2 (COX-2) gene and digestive system cancer risk have been inconclusive. The aim of this study was to comprehensively evaluate the genetic risk of the -765G>C polymorphism in the COX-2 gene for digestive system cancer. A search was performed in Pubmed, Medline (Ovid), Embase, CNKI, Weipu, Wanfang and CBM databases, covering all studies until Feb 10, 2014. Statistical analysis was performed using Revman5.2. A total of 10,814 cases and 16,174 controls in 38 case-control studies were included in this meta-analysis. The results indicated that C allele carriers (GC+CC) had a 20% increased risk of digestive system cancer when compared with the homozygote GG (odds ratio (OR)=1.20, 95% confidence interval (CI), 1.00-1.44 for GC+CC vs GG). In the subgroup analysis by ethnicity, significant elevated risks were associated with C allele carriers (GC+CC) in Asians (OR = 1.46, 95% CI=1.07-2.01, and p=0.02) and Africans (OR=2.12, 95% CI=1.57-2.87, and p< 0.00001), but not among Caucasians, Americans and mixed groups. For subgroup analysis by cancer type (GC+CC vs GG), significant associations were found between the -765G>C polymorphism and higher risk for gastric cancer (OR=1.64, 95% CI=1.03-2.61, and p=0.04), but not for colorectal cancer, oral cancer, esophageal cancer, and others. Regarding study design (GC+CC vs GG), no significant associations were found in then population-based case-control (PCC), hospital-based case-control (HCC) and family-based case-control (FCC) studies. This meta-analysis suggested that the -765G>C polymorphism of the COX-2 gene is a potential risk factor for digestive system cancer in Asians and Africans and gastric cancer overall.

Long-term survival after traumatic brain injury: a population-based analysis controlled for nonhead trauma.

PubMed

Brown, Allen W; Leibson, Cynthia L; Mandrekar, Jay; Ransom, Jeanine E; Malec, James F

2014-01-01

To examine the contribution of co-occurring nonhead injuries to hazard of death after traumatic brain injury (TBI). A random sample of Olmsted County, Minnesota, residents with confirmed TBI from 1987 through 1999 was identified. Each case was assigned an age- and sex-matched, non-TBI "regular control" from the population. For "special cases" with accompanying nonhead injuries, 2 matched "special controls" with nonhead injuries of similar severity were assigned. Vital status was followed from baseline (ie, injury date for cases, comparable dates for controls) through 2008. Cases were compared first with regular controls and second with regular or special controls, depending on case type. In total, 1257 cases were identified (including 221 special cases). For both cases versus regular controls and cases versus regular or special controls, the hazard ratio was increased from baseline to 6 months (10.82 [2.86-40.89] and 7.13 [3.10-16.39], respectively) and from baseline through study end (2.92 [1.74-4.91] and 1.48 [1.09-2.02], respectively). Among 6-month survivors, the hazard ratio was increased for cases versus regular controls (1.43 [1.06-2.15]) but not for cases versus regular or special controls (1.05 [0.80-1.38]). Among 6-month survivors, accounting for nonhead injuries resulted in a nonsignificant effect of TBI on long-term mortality.

Escherichia coli O157:H7 outbreak associated with consumption of ground beef, June-July 2002.

PubMed

Vogt, Richard L; Dippold, Laura

2005-01-01

A case-control and environmental study tested the hypothesis that purchasing and eating ground beef from a specific source was the cause of a cluster of cases of hemolytic uremic syndrome (HUS) and Escherichia coli (E. coli) O157:H7 gastroenteritis. A case-control study comparing risk factors was conducted over the telephone on nine case-patients with 23 selected controls. An environmental investigation was conducted that consisted of reviewing beef handling practices at a specific local supermarket and obtaining ground beef samples from the store and two households with case-patients. The analysis of the case-control study showed that eight case-patients (89%) purchased ground beef at Grocery Chain A compared with four controls who did not develop illness (17%) (matched odds ratio=undefined; 95% confidence interval 2.8, infinity; p=0.006). The environmental investigation showed that Grocery Chain A received meat from Meatpacker A. Laboratory analysis of meat samples from Meatpacker A and Grocery Chain A and stool samples from some patients recovered an identical strain of E. coli O157:H7 according to pulse-field gel electrophoresis. Both the case-control and environmental studies showed that purchasing ground beef at Grocery Chain A, which received ground beef from Meatpacker A, was the major risk factor for illness in eight case-patients; the ninth case-patient was found to be unrelated to the outbreak. Furthermore, meat from Meatpacker A was associated with a nationwide outbreak of E. coli O157:H7 illness that resulted in the second largest recall of beef in U.S. history at the time.

Early Complications and Outcomes in Combat Injury Related Invasive Fungal Wound Infections: A Case-Control Analysis

PubMed Central

Lewandowski, Louis R.; Weintrob, Amy C.; Tribble, David R.; Rodriguez, Carlos J.; Petfield, Joseph; Lloyd, Bradley A.; Murray, Clinton K.; Stinner, Daniel; Aggarwal, Deepak; Shaikh, Faraz; Potter, Benjamin K.

2015-01-01

Objective Clinicians have anecdotally noted that combat-related invasive fungal wound infections (IFIs) lead to residual limb shortening, additional days and operative procedures prior to initial wound closure, and high early complication rates. We evaluated the validity of these observations and identified risk factors that may impact time to initial wound closure. Design Retrospective review and case-control analysis. Setting Military hospitals. Patients/Participants United States military personnel injured during combat operations (2009–2011). The IFI cases were identified based upon the presence of recurrent, necrotic extremity wounds with mold growth in culture and/or histopathologic fungal evidence. Non-IFI controls were matched on injury pattern and severity. In a supplemental matching analysis, non-IFI controls were also matched by blood volume transfused within 24 hours of injury. Intervention None. Main Outcome Measurements Amputation revision rate and loss of functional levels. Results Seventy-one IFI cases (112 fungal-infected extremity wounds) were identified and matched to 160 control patients (315 non-IFI extremity wounds). The IFI wounds resulted in significantly more changes in amputation level (p<0.001). Additionally, significantly (p<0.001) higher number of operative procedures and longer duration to initial wound closure was associated with IFI. A shorter duration to initial wound closure was significantly associated with wounds lacking IFIs (Hazard ratio: 1.53; 95% CI: 1.17, 2.01). The supplemental matching analysis found similar results. Conclusions Our analysis indicates that IFIs adversely impact wound healing and patient recovery, requiring more frequent proximal amputation revisions and leading to higher early complication rates. PMID:26360542

Genome-wide interaction study of smoking behavior and non-small cell lung cancer risk in Caucasian population.

PubMed

Li, Yafang; Xiao, Xiangjun; Han, Younghun; Gorlova, Olga; Qian, David; Leighl, Natasha; Johansen, Jakob S; Barnett, Matt; Chen, Chu; Goodman, Gary; Cox, Angela; Taylor, Fiona; Woll, Penella; Wichmann, H-Erich; Manz, Judith; Muley, Thomas; Risch, Angela; Rosenberger, Albert; Arnold, Susanne M; Haura, Eric B; Bolca, Ciprian; Holcatova, Ivana; Janout, Vladimir; Kontic, Milica; Lissowska, Jolanta; Mukeria, Anush; Ognjanovic, Simona; Orlowski, Tadeusz M; Scelo, Ghislaine; Swiatkowska, Beata; Zaridze, David; Bakke, Per; Skaug, Vidar; Zienolddiny, Shanbeh; Duell, Eric J; Butler, Lesley M; Houlston, Richard; Soler Artigas, María; Grankvist, Kjell; Johansson, Mikael; Shepherd, Frances A; Marcus, Michael W; Brunnström, Hans; Manjer, Jonas; Melander, Olle; Muller, David C; Overvad, Kim; Trichopoulou, Antonia; Tumino, Rosario; Liu, Geoffrey; Bojesen, Stig E; Wu, Xifeng; Marchand, Loic Le; Albanes, Demetrios; Bickeböller, Heike; Aldrich, Melinda C; Bush, William S; Tardon, Adonina; Rennert, Gad; Teare, M Dawn; Field, John K; Kiemeney, Lambertus A; Lazarus, Philip; Haugen, Aage; Lam, Stephen; Schabath, Matthew B; Andrew, Angeline S; Bertazzi, Pier Alberto; Pesatori, Angela C; Christiani, David C; Caporaso, Neil; Johansson, Mattias; McKay, James D; Brennan, Paul; Hung, Rayjean J; Amos, Christopher I

2018-03-08

Non-small cell lung cancer is the most common type of lung cancer. Both environmental and genetic risk factors contribute to lung carcinogenesis. We conducted a genome-wide interaction analysis between single nucleotide polymorphisms (SNPs) and smoking status (never- versus ever-smokers) in a European-descent population. We adopted a two-step analysis strategy in the discovery stage: we first conducted a case-only interaction analysis to assess the relationship between SNPs and smoking behavior using 13336 non-small cell lung cancer cases. Candidate SNPs with P-value <0.001 were further analyzed using a standard case-control interaction analysis including 13970 controls. The significant SNPs with P-value <3.5 × 10-5 (correcting for multiple tests) from the case-control analysis in the discovery stage were further validated using an independent replication dataset comprising 5377 controls and 3054 non-small cell lung cancer cases. We further stratified the analysis by histological subtypes. Two novel SNPs, rs6441286 and rs17723637, were identified for overall lung cancer risk. The interaction odds ratio and meta-analysis P-value for these two SNPs were 1.24 with 6.96 × 10-7 and 1.37 with 3.49 × 10-7, respectively. In addition, interaction of smoking with rs4751674 was identified in squamous cell lung carcinoma with an odds ratio of 0.58 and P-value of 8.12 × 10-7. This study is by far the largest genome-wide SNP-smoking interaction analysis reported for lung cancer. The three identified novel SNPs provide potential candidate biomarkers for lung cancer risk screening and intervention. The results from our study reinforce that gene-smoking interactions play important roles in the etiology of lung cancer and account for part of the missing heritability of this disease.

Gall bladder cancer and the role of dietary and lifestyle factors: a case-control study in a North Indian population.

PubMed

Panda, Dipanjan; Sharma, Atul; Shukla, Nootan K; Jaiswal, Richa; Dwivedi, Sadanand; Raina, Vinod; Mohanti, Bidhu K; Deo, Surya V; Patra, Somdatta

2013-09-01

Most patients with gall bladder cancer (GBC) present in the advanced stage with a poor response to therapy. Prevention or early detection is the best way to prevent death, but this requires identification of susceptible subgroups. Keeping this in mind, this study was carried out to evaluate the association between selected demographic, lifestyle, and dietary factors and GBC. A hospital-based case-control study was carried out at the All India Institute of Medical Sciences (New Delhi, India). Cases were defined as newly registered confirmed primary GBC patients. Controls were defined as healthy relatives of patients other than that of GBC. Data were collected from February 2008 to October 2009 using a semistructured interview schedule from both cases and controls. Analysis was carried out using SPSS version 15 and Epi-Info version 6. Factors found to be significant in the bivariate analysis were entered in a multivariate logistic regression analysis. A total of 122 cases and 122 controls were included in the study. There was no significant difference in age (P=0.06) and sex (P=0.66) between the cases and the controls. In the bivariate analysis, factors found to be significantly associated with GBC were illiteracy [odds ratio (OR) 8.00, P=0.000], lower socioeconomic status (OR 2.45, P=0.000), parity more than 3 (OR 9.06, P=0.000), age at first pregnancy less than 20 years (OR 2.03, P=0.018), and the use of nonliquefied petroleum gas cooking fuel (OR 4.17, P=0.000). Higher vitamin C intake had a protective effect (OR 0.33, P=0.004). In the multivariate analysis, education, intake of vitamin C, parity, and type of fuel used were significant factors. The risk factors for GBC that have been identified in the present study delineate a high-risk population group that can be targeted for preventive measures including improvement in socioeconomic status, education and lifestyle, and dietary intervention, and avoidance of the use of nonliquefied petroleum gas as cooking fuel.

Adaptation of Chain Event Graphs for use with Case-Control Studies in Epidemiology.

PubMed

Keeble, Claire; Thwaites, Peter Adam; Barber, Stuart; Law, Graham Richard; Baxter, Paul David

2017-09-26

Case-control studies are used in epidemiology to try to uncover the causes of diseases, but are a retrospective study design known to suffer from non-participation and recall bias, which may explain their decreased popularity in recent years. Traditional analyses report usually only the odds ratio for given exposures and the binary disease status. Chain event graphs are a graphical representation of a statistical model derived from event trees which have been developed in artificial intelligence and statistics, and only recently introduced to the epidemiology literature. They are a modern Bayesian technique which enable prior knowledge to be incorporated into the data analysis using the agglomerative hierarchical clustering algorithm, used to form a suitable chain event graph. Additionally, they can account for missing data and be used to explore missingness mechanisms. Here we adapt the chain event graph framework to suit scenarios often encountered in case-control studies, to strengthen this study design which is time and financially efficient. We demonstrate eight adaptations to the graphs, which consist of two suitable for full case-control study analysis, four which can be used in interim analyses to explore biases, and two which aim to improve the ease and accuracy of analyses. The adaptations are illustrated with complete, reproducible, fully-interpreted examples, including the event tree and chain event graph. Chain event graphs are used here for the first time to summarise non-participation, data collection techniques, data reliability, and disease severity in case-control studies. We demonstrate how these features of a case-control study can be incorporated into the analysis to provide further insight, which can help to identify potential biases and lead to more accurate study results.

Using ancestry matching to combine family-based and unrelated samples for genome-wide association studies‡

PubMed Central

Crossett, Andrew; Kent, Brian P.; Klei, Lambertus; Ringquist, Steven; Trucco, Massimo; Roeder, Kathryn; Devlin, Bernie

2015-01-01

We propose a method to analyze family-based samples together with unrelated cases and controls. The method builds on the idea of matched case–control analysis using conditional logistic regression (CLR). For each trio within the family, a case (the proband) and matched pseudo-controls are constructed, based upon the transmitted and untransmitted alleles. Unrelated controls, matched by genetic ancestry, supplement the sample of pseudo-controls; likewise unrelated cases are also paired with genetically matched controls. Within each matched stratum, the case genotype is contrasted with control pseudo-control genotypes via CLR, using a method we call matched-CLR (mCLR). Eigenanalysis of numerous SNP genotypes provides a tool for mapping genetic ancestry. The result of such an analysis can be thought of as a multidimensional map, or eigenmap, in which the relative genetic similarities and differences amongst individuals is encoded in the map. Once constructed, new individuals can be projected onto the ancestry map based on their genotypes. Successful differentiation of individuals of distinct ancestry depends on having a diverse, yet representative sample from which to construct the ancestry map. Once samples are well-matched, mCLR yields comparable power to competing methods while ensuring excellent control over Type I error. PMID:20862653

Resolvent analysis of suboptimal control for turbulent skin friction drag reduction

NASA Astrophysics Data System (ADS)

Nakashima, Satoshi; Fukagata, Koji; Luhar, Mitul

2017-11-01

We study the drag reduction mechanisms of suboptimal control (Lee et al. 1998) via the resolvent formulation developed by McKeon and Sharma (2010). Under this formulation, the nonlinear term in the Navier-Stokes equations is regarded as a forcing which acts upon the linear dynamics to output a velocity response across Fourier space. This analysis enables targeted analyses of the effects of the control on modes resembling dynamically important coherent structures such as the near-wall (NW) cycle. Suboptimal control generates blowing and suction at the wall that is proportional to the streamwise (Case ST) or spanwise (Case SP) wall shear-stress, with the magnitude of blowing and suction being a design parameter. Both Case ST and SP can suppress resolvent modes resembling the NW cycle. However, for Case ST, the analysis reveals that the control leads to substantial increase in amplification for structures that are long in the spanwise direction. High actuation of such energetic spanwise structures was confirmed by conducting limited direct numerical simulations. In addition to the study of modes resembling the NW cycle, we will discuss modes of varying propagating speed and wavelength to provide insight into the effects of suboptimal control across spectral space. This work was supported through Grant-in-Aid for Scientific Research (C) (No. 25420129) by Japan Society for the Promotion of Science (JSPS).

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

PubMed

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

2016-11-01

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

Pathway-based outlier method reveals heterogeneous genomic structure of autism in blood transcriptome

PubMed Central

2013-01-01

Background Decades of research strongly suggest that the genetic etiology of autism spectrum disorders (ASDs) is heterogeneous. However, most published studies focus on group differences between cases and controls. In contrast, we hypothesized that the heterogeneity of the disorder could be characterized by identifying pathways for which individuals are outliers rather than pathways representative of shared group differences of the ASD diagnosis. Methods Two previously published blood gene expression data sets – the Translational Genetics Research Institute (TGen) dataset (70 cases and 60 unrelated controls) and the Simons Simplex Consortium (Simons) dataset (221 probands and 191 unaffected family members) – were analyzed. All individuals of each dataset were projected to biological pathways, and each sample’s Mahalanobis distance from a pooled centroid was calculated to compare the number of case and control outliers for each pathway. Results Analysis of a set of blood gene expression profiles from 70 ASD and 60 unrelated controls revealed three pathways whose outliers were significantly overrepresented in the ASD cases: neuron development including axonogenesis and neurite development (29% of ASD, 3% of control), nitric oxide signaling (29%, 3%), and skeletal development (27%, 3%). Overall, 50% of cases and 8% of controls were outliers in one of these three pathways, which could not be identified using group comparison or gene-level outlier methods. In an independently collected data set consisting of 221 ASD and 191 unaffected family members, outliers in the neurogenesis pathway were heavily biased towards cases (20.8% of ASD, 12.0% of control). Interestingly, neurogenesis outliers were more common among unaffected family members (Simons) than unrelated controls (TGen), but the statistical significance of this effect was marginal (Chi squared P < 0.09). Conclusions Unlike group difference approaches, our analysis identified the samples within the case and control groups that manifested each expression signal, and showed that outlier groups were distinct for each implicated pathway. Moreover, our results suggest that by seeking heterogeneity, pathway-based outlier analysis can reveal expression signals that are not apparent when considering only shared group differences. PMID:24063311

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

PubMed

Keogh, Ruth H; White, Ian R

2013-10-15

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

High Accuracy Liquid Propellant Slosh Predictions Using an Integrated CFD and Controls Analysis Interface

NASA Technical Reports Server (NTRS)

Marsell, Brandon; Griffin, David; Schallhorn, Dr. Paul; Roth, Jacob

2012-01-01

Coupling computational fluid dynamics (CFD) with a controls analysis tool elegantly allows for high accuracy predictions of the interaction between sloshing liquid propellants and th e control system of a launch vehicle. Instead of relying on mechanical analogs which are not valid during aU stages of flight, this method allows for a direct link between the vehicle dynamic environments calculated by the solver in the controls analysis tool to the fluid flow equations solved by the CFD code. This paper describes such a coupling methodology, presents the results of a series of test cases, and compares said results against equivalent results from extensively validated tools. The coupling methodology, described herein, has proven to be highly accurate in a variety of different cases.

Integrated CFD and Controls Analysis Interface for High Accuracy Liquid Propellant Slosh Predictions

NASA Technical Reports Server (NTRS)

Marsell, Brandon; Griffin, David; Schallhorn, Paul; Roth, Jacob

2012-01-01

Coupling computational fluid dynamics (CFD) with a controls analysis tool elegantly allows for high accuracy predictions of the interaction between sloshing liquid propellants and the control system of a launch vehicle. Instead of relying on mechanical analogs which are n0t va lid during all stages of flight, this method allows for a direct link between the vehicle dynamic environments calculated by the solver in the controls analysis tool to the fluid now equations solved by the CFD code. This paper describes such a coupling methodology, presents the results of a series of test cases, and compares said results against equivalent results from extensively validated tools. The coupling methodology, described herein, has proven to be highly accurate in a variety of different cases.

Risk factors for late onset gram-negative infections: a case-control study.

PubMed

Samanta, Srabani; Farrer, Kate; Breathnach, Aodhan; Heath, Paul T

2011-01-01

To determine the incidence, mortality and risk factors for neonatal late onset gram-negative sepsis and meningitis (LOGNS). Retrospective case-control study. Tertiary neonatal unit in London. Consecutive inborn infants with late onset (>48 h of life) invasive gram-negative infections diagnosed between 1999 and 2005. Controls were healthy infants matched for gestation and time of admission to the neonatal unit. Clinical and risk factor data. 73 cases of LOGNS were identified of which 48 were inborn and included in the study (incidence 1.85/1000 live births). Enterobacter spp. (28%), Escherichia coli (27%) and Klebsiella spp. (21%) were the most common pathogens. The majority of infants were of very low birthweight (VLBW; 79%), and cases and controls were well matched (median gestation 26 weeks). Overall case death was 27% in cases versus 13.5% in controls (p=0.08). There was no significant difference between cases and controls regarding maternal risk factors. Mechanical ventilation, total parenteral nutrition (TPN) and its duration, presence of a central venous line and its duration, use of specific antibiotics and the occurrence of necrotising enterocolitis at or before the first positive culture were all significantly associated with case status in univariate analysis. In multivariate logistic regression analysis, only duration of TPN at or before first positive blood culture remained independently associated with LOGNS (p<0.001). LOGNS occurs predominantly in VLBW infants. When the influence of gestational age is accounted for, the only independent risk factor found for late onset gram-negative neonatal infections is the duration of TPN.

Exome-based analysis of cardiac arrhythmia, respiratory control, and epilepsy genes in sudden unexpected death in epilepsy.

PubMed

Bagnall, Richard D; Crompton, Douglas E; Petrovski, Slavé; Lam, Lien; Cutmore, Carina; Garry, Sarah I; Sadleir, Lynette G; Dibbens, Leanne M; Cairns, Anita; Kivity, Sara; Afawi, Zaid; Regan, Brigid M; Duflou, Johan; Berkovic, Samuel F; Scheffer, Ingrid E; Semsarian, Christopher

2016-04-01

The leading cause of epilepsy-related premature mortality is sudden unexpected death in epilepsy (SUDEP). The cause of SUDEP remains unknown. To search for genetic risk factors in SUDEP cases, we performed an exome-based analysis of rare variants. Demographic and clinical information of 61 SUDEP cases were collected. Exome sequencing and rare variant collapsing analysis with 2,936 control exomes were performed to test for genes enriched with damaging variants. Additionally, cardiac arrhythmia, respiratory control, and epilepsy genes were screened for variants with frequency of <0.1% and predicted to be pathogenic with multiple in silico tools. The 61 SUDEP cases were categorized as definite SUDEP (n = 54), probable SUDEP (n = 5), and definite SUDEP plus (n = 2). We identified de novo mutations, previously reported pathogenic mutations, or candidate pathogenic variants in 28 of 61 (46%) cases. Four SUDEP cases (7%) had mutations in common genes responsible for the cardiac arrhythmia disease, long QT syndrome (LQTS). Nine cases (15%) had candidate pathogenic variants in dominant cardiac arrhythmia genes. Fifteen cases (25%) had mutations or candidate pathogenic variants in dominant epilepsy genes. No gene reached genome-wide significance with rare variant collapsing analysis; however, DEPDC5 (p = 0.00015) and KCNH2 (p = 0.0037) were among the top 30 genes, genome-wide. A sizeable proportion of SUDEP cases have clinically relevant mutations in cardiac arrhythmia and epilepsy genes. In cases with an LQTS gene mutation, SUDEP may occur as a result of a predictable and preventable cause. Understanding the genetic basis of SUDEP may inform cascade testing of at-risk family members. © 2016 American Neurological Association.

The association between human papillomavirus infection and lung cancer: a system review and meta-analysis

PubMed Central

Xiong, Wei-Min; Xu, Qiu-Ping; Li, Xu; Xiao, Ren-Dong; Cai, Lin; He, Fei

2017-01-01

To estimate the global attributable fraction of human papillomavirus (HPV) in lung cancer, we provided updated information through a system review and meta-analysis. We did a literature search on PubMed, Ovid and Web of Science to identify case-control studies and cohort studies that detected HPV in lung carcinomas. We included studies that tested 30 or more cases and were published before Feb 28, 2017. We collected information about gender, smoking status, HPV detection methods, HPV types, materials and clinical features. If it was not possible to abstract the required information directly from the papers, we contacted the authors. A meta-analysis was performed to calculate the pooled effect sizes (OR/RR) with 95% confidence intervals (CI) including subgroup analysis and meta-regression to explore sources of heterogeneity, by Stata 13.0 software. 36 case-control studies, contributing data for 6,980 cases of lung cancer and 7,474 controls from 17 countries and one cohort study with 24,162 exposed and 1,026,986 unexposed from China were included. HPV infection was associated with cancer of lung, pooled OR was 3.64 (95% CI: 2.60–5.08), calculated with the random-effects model. Pooled OR for allogeneic case-control studies, self-matched case-control studies and nested case-control studies were 6.71 (95% CI: 4.07–11.07), 2.59 (95% CI: 1.43–4.69) and 0.92 (95% CI: 0.63–1.36), respectively. Pooled OR for HPV 16 and HPV 18 infection, were 3.14 (95% CI: 2.07–4.76) and 2.25 (95% CI: 1.49–3.40), respectively. We also found that HPV infection may be associated with squamous cell carcinoma, adenocarcinoma and small cell carcinoma. There is evidence that HPV infection, especially HPV 16 and HPV 18 infection, significantly increase the risk of lung cancer. Future research needs to focus attention toward whether an HPV vaccine can effectively reduce the incidence of lung cancer. PMID:29221217

Thromboembolism Following Shoulder Arthroscopy

PubMed Central

Schick, Cameron W.; Westermann, Robert W.; Gao, Yubo; Abboud, Joseph A.; Wolf, Brian R.

2014-01-01

Background: Thromboembolism following shoulder arthroscopy is considered an uncommon complication, with fewer than 50 cases reported in the literature. Arthroscopy of the shoulder is one of the most commonly performed orthopaedic procedures, with low associated risks. Purpose: To identify potential risk factors for the development of venous thromboembolism (VTE) following shoulder arthroscopy and to determine the overall incidence of this complication. Study Design: Case-control study; Level of evidence, 3. Methods: A retrospective case-control review was performed of patients who developed symptomatic deep venous thrombosis (DVT) or pulmonary embolism (PE) following shoulder arthroscopy. Multiple surgeons from across North America were queried. For every case of DVT or PE identified, 2 control cases of shoulder arthroscopy were analyzed. The incidence of DVT/PE following shoulder arthroscopy was determined. A univariate analysis and a multivariate logistic regression model were conducted to identify any potential risk factors for the development of VTE following shoulder arthroscopy. Results: A total of 17 surgeons participated in this study and had performed a total of 15,033 cases of shoulder arthroscopy from September 2002 through August 2011. Eleven of the 17 participating surgeons had had a patient with a VTE complication during this time frame. The incidence of VTE in the 15,033 cases was 0.15%; 22 patients of the 15,033 patients had a DVT (n = 15) and/or PE (n = 8). Forty-four control cases were also analyzed. Univariate and multivariate analyses were performed. No significant risk factors were identified other than patient positioning. All cases and controls were positioned in the beach-chair position for surgery. Conclusion: The results of this study show that although rare, VTE occurs following shoulder arthroscopy at a rate of 0.15%. The variables analyzed in the cases of VTE compared with the control cases did not show any significant risk factors. All cases were positioned in the beach-chair position. Further analysis of future cases is warranted. PMID:26535285

Chronic atrophic gastritis in association with hair mercury level.

PubMed

Xue, Zeyun; Xue, Huiping; Jiang, Jianlan; Lin, Bing; Zeng, Si; Huang, Xiaoyun; An, Jianfu

2014-11-01

The objective of this study was to explore hair mercury level in association with chronic atrophic gastritis, a precancerous stage of gastric cancer (GC), and thus provide a brand new angle of view on the timely intervention of precancerous stage of GC. We recruited 149 healthy volunteers as controls and 152 patients suffering from chronic gastritis as cases. The controls denied upper gastrointestinal discomforts, and the cases were diagnosed as chronic superficial gastritis (n=68) or chronic atrophic gastritis (n=84). We utilized Mercury Automated Analyzer (NIC MA-3000) to detect hair mercury level of both healthy controls and cases of chronic gastritis. The statistic of measurement data was expressed as mean ± standard deviation, which was analyzed using Levene variance equality test and t test. Pearson correlation analysis was employed to determine associated factors affecting hair mercury levels, and multiple stepwise regression analysis was performed to deduce regression equations. Statistical significance is considered if p value is less than 0.05. The overall hair mercury level was 0.908949 ± 0.8844490 ng/g [mean ± standard deviation (SD)] in gastritis cases and 0.460198 ± 0.2712187 ng/g (mean±SD) in healthy controls; the former level was significantly higher than the latter one (p=0.000<0.01). The hair mercury level in chronic atrophic gastritis subgroup was 1.155220 ± 0.9470246 ng/g (mean ± SD) and that in chronic superficial gastritis subgroup was 0.604732 ± 0.6942509 ng/g (mean ± SD); the former level was significantly higher than the latter level (p<0.01). The hair mercury level in chronic superficial gastritis cases was significantly higher than that in healthy controls (p<0.05). The hair mercury level in chronic atrophic gastritis cases was significantly higher than that in healthy controls (p<0.01). Stratified analysis indicated that the hair mercury level in healthy controls with eating seafood was significantly higher than that in healthy controls without eating seafood (p<0.01) and that the hair mercury level in chronic atrophic gastritis cases was significantly higher than that in chronic superficial gastritis cases (p<0.01). Pearson correlation analysis indicated that eating seafood was most correlated with hair mercury level and positively correlated in the healthy controls and that the severity of gastritis was most correlated with hair mercury level and positively correlated in the gastritis cases. Multiple stepwise regression analysis indicated that the regression equation of hair mercury level in controls could be expressed as 0.262 multiplied the value of eating seafood plus 0.434, the model that was statistically significant (p<0.01). Multiple stepwise regression analysis also indicated that the regression equation of hair mercury level in gastritis cases could be expressed as 0.305 multiplied the severity of gastritis, the model that was also statistically significant (p<0.01). The graphs of regression standardized residual for both controls and cases conformed to normal distribution. The main positively correlated factor affecting the hair mercury level is eating seafood in healthy people whereas the predominant positively correlated factor affecting the hair mercury level is the severity of gastritis in chronic gastritis patients. That is to say, the severity of chronic gastritis is positively correlated with the level of hair mercury. The incessantly increased level of hair mercury possibly reflects the development of gastritis from normal stomach to superficial gastritis and to atrophic gastritis. The detection of hair mercury is potentially a means to predict the severity of chronic gastritis and possibly to insinuate the environmental mercury threat to human health in terms of gastritis or even carcinogenesis.

Mobile phone use and risk of tumors: a meta-analysis.

PubMed

Myung, Seung-Kwon; Ju, Woong; McDonnell, Diana D; Lee, Yeon Ji; Kazinets, Gene; Cheng, Chih-Tao; Moskowitz, Joel M

2009-11-20

Case-control studies have reported inconsistent findings regarding the association between mobile phone use and tumor risk. We investigated these associations using a meta-analysis. We searched MEDLINE (PubMed), EMBASE, and the Cochrane Library in August 2008. Two evaluators independently reviewed and selected articles based on predetermined selection criteria. Of 465 articles meeting our initial criteria, 23 case-control studies, which involved 37,916 participants (12,344 patient cases and 25,572 controls), were included in the final analyses. Compared with never or rarely having used a mobile phone, the odds ratio for overall use was 0.98 for malignant and benign tumors (95% CI, 0.89 to 1.07) in a random-effects meta-analysis of all 23 studies. However, a significant positive association (harmful effect) was observed in a random-effects meta-analysis of eight studies using blinding, whereas a significant negative association (protective effect) was observed in a fixed-effects meta-analysis of 15 studies not using blinding. Mobile phone use of 10 years or longer was associated with a risk of tumors in 13 studies reporting this association (odds ratio = 1.18; 95% CI, 1.04 to 1.34). Further, these findings were also observed in the subgroup analyses by methodologic quality of study. Blinding and methodologic quality of study were strongly associated with the research group. The current study found that there is possible evidence linking mobile phone use to an increased risk of tumors from a meta-analysis of low-biased case-control studies. Prospective cohort studies providing a higher level of evidence are needed.

Raising standards while watching the bottom line: making a business case for infection control.

PubMed

Perencevich, Eli N; Stone, Patricia W; Wright, Sharon B; Carmeli, Yehuda; Fisman, David N; Cosgrove, Sara E

2007-10-01

While society would benefit from a reduced incidence of nosocomial infections, there is currently no direct reimbursement to hospitals for the purpose of infection control, which forces healthcare institutions to make economic decisions about funding infection control activities. Demonstrating value to administrators is an increasingly important function of the hospital epidemiologist because healthcare executives are faced with many demands and shrinking budgets. Aware of the difficulties that face local infection control programs, the Society for Healthcare Epidemiology of America (SHEA) Board of Directors appointed a task force to draft this evidence-based guideline to assist hospital epidemiologists in justifying and expanding their programs. In Part 1, we describe the basic steps needed to complete a business-case analysis for an individual institution. A case study based on a representative infection control intervention is provided. In Part 2, we review important basic economic concepts and describe approaches that can be used to assess the financial impact of infection prevention, surveillance, and control interventions, as well as the attributable costs of specific healthcare-associated infections. Both parts of the guideline aim to provide the hospital epidemiologist, infection control professional, administrator, and researcher with the tools necessary to complete a thorough business-case analysis and to undertake an outcome study of a nosocomial infection or an infection control intervention.

Meta-analyses of the Association of Sleep Apnea with Insulin Resistance, and the Effects of CPAP on HOMA-IR, Adiponectin, and Visceral Adipose Fat.

PubMed

Iftikhar, Imran H; Hoyos, Camilla M; Phillips, Craig L; Magalang, Ulysses J

2015-04-15

We sought to conduct an updated meta-analysis of randomized controlled trials (RCTs) on the effect of continuous positive airway pressure (CPAP) on insulin resistance, as measured by homeostasis model assessment of insulin resistance (HOMA-IR), visceral abdominal fat (VAF), and adiponectin. Additionally, we performed a separate meta-analysis and meta-regression of studies on the association of insulin resistance and obstructive sleep apnea (OSA). All included studies were searched from PubMed (from conception to March 15, 2014). Data were pooled across all included RCTs as the mean difference in HOMA-IR and VAF, and as the standardized mean difference in the case of adiponectin analysis. From the included case-control studies, data on the difference of HOMA-IR between cases and controls were pooled across all studies, as the standardized mean difference (SMD). There was a significant difference in HOMA-IR (-0.43 [95% CIs: -0.75 to -0.11], p = 0.008) between CPAP treated and non CPAP treated participants. However, there was no significant difference in VAF or adiponectin; (-47.93 [95% CI: -112.58 to 16.72], p = 0.14) and (-0.06 [95% CI: -0.28 to 0.15], p = 0.56), respectively. Meta-analysis of 16 case-control studies showed a pooled SMD in HOMA-IR of 0.51 (95% CI: 0.28 to 0.75), p ≤ 0.001, between cases and controls. The results of our meta-analyses show that CPAP has a favorable effect on insulin resistance. This effect is not associated with any significant changes in total adiponectin levels or amount of VAF. Our findings also confirm a significant association between OSA and insulin resistance. © 2015 American Academy of Sleep Medicine.

Bleeding risk under selective serotonin reuptake inhibitor (SSRI) antidepressants: A meta-analysis of observational studies.

PubMed

Laporte, Silvy; Chapelle, Céline; Caillet, Pascal; Beyens, Marie-Noëlle; Bellet, Florelle; Delavenne, Xavier; Mismetti, Patrick; Bertoletti, Laurent

2017-04-01

Selective serotonin reuptake inhibitors (SSRIs) have been reported to be potentially associated with an increased risk of bleeding. A meta-analysis of observational studies was conducted to quantify this risk. Case-control and cohort studies investigating bleeding risk under SSRI therapy were retrieved by searching the Medline, Pascal, Google Scholar and Scopus databases. Case-control studies were included if they reported bleeding incidents with and without the use of SSRIs and cohort studies were included if they reported the rate of bleeds among SSRI users and non-users. The main outcome was severe bleeding, whatever the site. Only data concerning SSRI belonging to the ATC class N06AB were used. For both case-control and cohort studies, we recorded the adjusted effect estimates and their 95% confidence intervals (CI). Pooled adjusted odds ratio (OR) estimates were computed for case-control and cohort studies using an inverse-variance model. Meta-analysis of the adjusted ORs of 42 observational studies showed a significant association between SSRI use and the risk of bleeding [OR 1.41 (95% CI 1.27-1.57), random effect model, p<0.0001]. The association was found for the 31 case-control studies (1,255,073 patients), with an increased risk of 41% of bleeding [OR 1.41 (95% CI 1.25-1.60)], as well as for the 11 cohort studies including 187,956 patients [OR 1.36 (95% CI 1.12-1.64)]. Subgroup analyses showed that the association remained constant whatever the characteristics of studies. This meta-analysis shows an increased risk of bleeding of at least 36% (from 12% to 64%) based on the high-level of observational studies with SSRIs use. Copyright © 2016 Elsevier Ltd. All rights reserved.

ERAP1 variants are associated with ankylosing spondylitis in East Asian population: a new Chinese case-control study and meta-analysis of published series.

PubMed

Chen, C; Zhang, X

2015-06-01

Endoplasmic reticulum aminopeptidase 1 (ERAP1) has been confirmed to be associated with ankylosing spondylitis (AS) in Caucasian. However, whether they are associated with AS in East Asian population remains unidentified. We investigated this relationship by a new Chinese case-control study and a meta-analysis of published series. 368 cases and 460 controls were recruited in the Chinese case-control study. Genotyping was completed using the chip-based matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Allelic associations were analysed using contingency tables. In the meta-analysis, up to 2748 cases and 2774 controls from seven different studies and the new Chinese study were combined using Review Manager software version 5.1.1. Mantel-Haenszel or Inverse Variance test was used to calculate fixed or random-effects pooled ORs. In the new Chinese study, strong association with AS was observed for marker rs10050860, rs27434 and rs1065407 at P value of <0.001. Moderate association was observed for rs30187 at P value of <0.01, while no association was observed for rs27044 (P = 0.37) and rs2287987 (P = 0.23). The meta-analysis showed that rs27037 and rs30187 were strongly associated with AS (P < 0.00001). Significant association was also observed for rs27434 (P = 0.001). No association was shown for rs27044 (P = 0.70). We concluded that ERAP1 variants are associated with AS in East Asian population, indicating a common pathogenic mechanism for AS in East Asians and Caucasians. © 2015 John Wiley & Sons Ltd.

The Utility of Case-Control Methods for Health Policy and Planning Analysis: An Illustration from Kinshasa, Zaire.

ERIC Educational Resources Information Center

Mock, Nancy B.; And Others

1993-01-01

The use of case-control methodology as an applied policy/planning research tool in assessing the potential effectiveness of behavioral interventions is studied in connection with diarrhea control in Zaire. Results with 107 matched pairs of children demonstrate the importance of hygiene-related knowledge and the utility of the research approach.…

Inventory Control System for a Healthcare Apparel Service Centre with Stockout Risk: A Case Analysis

PubMed Central

Hui, Chi-Leung

2017-01-01

Based on the real-world inventory control problem of a capacitated healthcare apparel service centre in Hong Kong which provides tailor-made apparel-making services for the elderly and disabled people, this paper studies a partial backordered continuous review inventory control problem in which the product demand follows a Poisson process with a constant lead time. The system is controlled by an (Q,r) inventory policy which incorporate the stockout risk, storage capacity, and partial backlog. The healthcare apparel service centre, under the capacity constraint, aims to minimize the inventory cost and achieving a low stockout risk. To address this challenge, an optimization problem is constructed. A real case-based data analysis is conducted, and the result shows that the expected total cost on an order cycle is reduced substantially at around 20% with our proposed optimal inventory control policy. An extensive sensitivity analysis is conducted to generate additional insights. PMID:29527283

Inventory Control System for a Healthcare Apparel Service Centre with Stockout Risk: A Case Analysis.

PubMed

Pan, An; Hui, Chi-Leung

2017-01-01

Based on the real-world inventory control problem of a capacitated healthcare apparel service centre in Hong Kong which provides tailor-made apparel-making services for the elderly and disabled people, this paper studies a partial backordered continuous review inventory control problem in which the product demand follows a Poisson process with a constant lead time. The system is controlled by an ( Q , r ) inventory policy which incorporate the stockout risk, storage capacity, and partial backlog. The healthcare apparel service centre, under the capacity constraint, aims to minimize the inventory cost and achieving a low stockout risk. To address this challenge, an optimization problem is constructed. A real case-based data analysis is conducted, and the result shows that the expected total cost on an order cycle is reduced substantially at around 20% with our proposed optimal inventory control policy. An extensive sensitivity analysis is conducted to generate additional insights.

Gap-metric-based robustness analysis of nonlinear systems with full and partial feedback linearisation

NASA Astrophysics Data System (ADS)

Al-Gburi, A.; Freeman, C. T.; French, M. C.

2018-06-01

This paper uses gap metric analysis to derive robustness and performance margins for feedback linearising controllers. Distinct from previous robustness analysis, it incorporates the case of output unstructured uncertainties, and is shown to yield general stability conditions which can be applied to both stable and unstable plants. It then expands on existing feedback linearising control schemes by introducing a more general robust feedback linearising control design which classifies the system nonlinearity into stable and unstable components and cancels only the unstable plant nonlinearities. This is done in order to preserve the stabilising action of the inherently stabilising nonlinearities. Robustness and performance margins are derived for this control scheme, and are expressed in terms of bounds on the plant nonlinearities and the accuracy of the cancellation of the unstable plant nonlinearity by the controller. Case studies then confirm reduced conservatism compared with standard methods.

Allergies and Risk of Head and Neck Cancer: An Original Study plus Meta-Analysis

PubMed Central

Lo, Hung-I; Huang, Cheng-Chih; Lee, Wei-Ting; Huang, Jehn-Shyun; Chen, Ken-Chung; Wong, Tung-Yiu; Tsai, Sen-Tien; Yen, Chia-Jui; Wu, Yuan-Hua; Hsueh, Wei-Ting; Yang, Ming-Wei; Wu, Shang-Yin; Chang, Jang-Yang; Chang, Kwang-Yu; Lin, Chen-Lin; Wang, Fang-Ting; Wang, Yi-Hui; Weng, Ya-Ling; Yang, Han-Chien; Chang, Jeffrey S.

2013-01-01

Background Although the relationship between allergy and cancer has been investigated extensively, the role of allergy in head and neck cancer (HNC) appears less consistent. It is not clear whether allergies can independently influence the risk of HNC in the presence of known strong environmental risk factors, including consumption of alcohol, betel quid, and cigarette. Methods The current paper reports results from: 1) an original hospital-based case-control study, which included 252 incident cases of HNC and 236 controls frequency-matched to cases on sex and age; and 2) a meta-analysis combining the results of the current case-control study and 13 previously published studies (9 cohort studies with 727,569 subjects and 550 HNC outcomes and 5 case-control studies with 4,017 HNC cases and 10,928 controls). Results In the original case-control study, we observed a strong inverse association between allergies and HNC [odds ratio = 0.41, 95% confidence interval (CI): 0.27–0.62]. The meta-analysis also indicated a statistically significant inverse association between HNC and allergies [meta-relative risk (RR) = 0.76, 95% CI: 0.63–0.91], particularly strong for allergic rhinitis (meta-RR = 0.55, 95% CI: 0.40–0.76). In addition, the inverse association between allergies and HNC was observed only among men (meta-RR = 0.67, 95% CI: 0.54–0.84) but not among women (meta-RR = 0.98, 95% CI: 0.81–1.18). Conclusions These findings suggest that immunity plays an influential role in the risk of HNC. Future studies investigating immune biomarkers, including cytokine profiles and genetic polymorphisms, are warranted to further delineate the relationship between allergies and HNC. Understanding the relationship between allergies and HNC may help devise effective strategies to reduce and treat HNC. PMID:23383309

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.

[Voice disorders related to job stress in teaching: a case-control study].

PubMed

Giannini, Susana Pimentel Pinto; Latorre, Maria do Rosário Dias de Oliveira; Ferreira, Leslie Piccolotto

2012-11-01

This case-control study aimed to test the association between voice disorders and job stress among public schoolteachers in São Paulo, Brazil. The groups consisted of teachers with (n = 165) and without (n = 105) voice-related complaints. Both groups answered the questionnaires Conditions of Vocal Production and Job Stress Scale. Analysis of cases and controls showed comparable samples, differing only by vocal symptoms. There was a statistically significant difference between cases and controls in relation to job stress involving high strain (OR = 2.1; 95%CI: 1.1-3.9), which places high demands combined with low job control. High strain in cases in this study represents the highest risk of physical and mental disorders for teachers. Loss of voice prevents teachers from continuing in their professional role, eliminates their professional identity, and jeopardizes their career.

Linkage Analysis in Autoimmune Addison's Disease: NFATC1 as a Potential Novel Susceptibility Locus.

PubMed

Mitchell, Anna L; Bøe Wolff, Anette; MacArthur, Katie; Weaver, Jolanta U; Vaidya, Bijay; Erichsen, Martina M; Darlay, Rebecca; Husebye, Eystein S; Cordell, Heather J; Pearce, Simon H S

2015-01-01

Autoimmune Addison's disease (AAD) is a rare, highly heritable autoimmune endocrinopathy. It is possible that there may be some highly penetrant variants which confer disease susceptibility that have yet to be discovered. DNA samples from 23 multiplex AAD pedigrees from the UK and Norway (50 cases, 67 controls) were genotyped on the Affymetrix SNP 6.0 array. Linkage analysis was performed using Merlin. EMMAX was used to carry out a genome-wide association analysis comparing the familial AAD cases to 2706 UK WTCCC controls. To explore some of the linkage findings further, a replication study was performed by genotyping 64 SNPs in two of the four linked regions (chromosomes 7 and 18), on the Sequenom iPlex platform in three European AAD case-control cohorts (1097 cases, 1117 controls). The data were analysed using a meta-analysis approach. In a parametric analysis, applying a rare dominant model, loci on chromosomes 7, 9 and 18 had LOD scores >2.8. In a non-parametric analysis, a locus corresponding to the HLA region on chromosome 6, known to be associated with AAD, had a LOD score >3.0. In the genome-wide association analysis, a SNP cluster on chromosome 2 and a pair of SNPs on chromosome 6 were associated with AAD (P <5x10-7). A meta-analysis of the replication study data demonstrated that three chromosome 18 SNPs were associated with AAD, including a non-synonymous variant in the NFATC1 gene. This linkage study has implicated a number of novel chromosomal regions in the pathogenesis of AAD in multiplex AAD families and adds further support to the role of HLA in AAD. The genome-wide association analysis has also identified a region of interest on chromosome 2. A replication study has demonstrated that the NFATC1 gene is worthy of future investigation, however each of the regions identified require further, systematic analysis.

Genome-scale case-control analysis of CD4+ T-cell DNA methylation in juvenile idiopathic arthritis reveals potential targets involved in disease.

PubMed

Ellis, Justine A; Munro, Jane E; Chavez, Raul A; Gordon, Lavinia; Joo, Jihoon E; Akikusa, Jonathan D; Allen, Roger C; Ponsonby, Anne-Louise; Craig, Jeffrey M; Saffery, Richard

2012-11-13

Juvenile Idiopathic Arthritis (JIA) is a complex autoimmune rheumatic disease of largely unknown cause. Evidence is growing that epigenetic variation, particularly DNA methylation, is associated with autoimmune disease. However, nothing is currently known about the potential role of aberrant DNA methylation in JIA. As a first step to addressing this knowledge gap, we have profiled DNA methylation in purified CD4+ T cells from JIA subjects and controls. Genomic DNA was isolated from peripheral blood CD4+ T cells from 14 oligoarticular and polyarticular JIA cases with active disease, and healthy age- and sex-matched controls. Genome-scale methylation analysis was carried out using the Illumina Infinium HumanMethylation27 BeadChip. Methylation data at >25,000 CpGs was compared in a case-control study design. Methylation levels were significantly different (FDR adjusted p<0.1) at 145 loci. Removal of four samples exposed to methotrexate had a striking impact on the outcome of the analysis, reducing the number of differentially methylated loci to 11. The methotrexate-naive analysis identified reduced methylation at the gene encoding the pro-inflammatory cytokine IL32, which was subsequently replicated using a second analysis platform and a second set of case-control pairs. Our data suggests that differential T cell DNA methylation may be a feature of JIA, and that reduced methylation at IL32 is associated with this disease. Further work in larger prospective and longitudinal sample collections is required to confirm these findings, assess whether the identified differences are causal or consequential of disease, and further investigate the epigenetic modifying properties of therapeutic regimens.

A Systematic Review and Aggregated Analysis on the Impact of Amyloid PET Brain Imaging on the Diagnosis, Diagnostic Confidence, and Management of Patients being Evaluated for Alzheimer's Disease.

PubMed

Fantoni, Enrico R; Chalkidou, Anastasia; O' Brien, John T; Farrar, Gill; Hammers, Alexander

2018-01-01

Amyloid PET (aPET) imaging could improve patient outcomes in clinical practice, but the extent of impact needs quantification. To provide an aggregated quantitative analysis of the value added by aPET in cognitively impaired subjects. Systematic literature searches were performed in Embase and Medline until January 2017. 1,531 cases over 12 studies were included (1,142 cases over seven studies in the primary analysis where aPET was the key biomarker; the remaining cases included as defined groups in the secondary analysis). Data was abstracted by consensus among two observers and assessed for bias. Clinical utility was measured by diagnostic change, diagnostic confidence, and patient management before and after aPET. Three groups were further analyzed: control patients for whom feedback of aPET scan results was delayed; aPET Appropriate Use Criteria (AUC+) cases; and patients undergoing additional FDG/CSF testing. For 1,142 cases with only aPET, 31.3% of diagnoses were revised, whereas 3.2% of diagnoses changed in the delayed aPET control group (p < 0.0001). Increased diagnostic confidence following aPET was found for 62.1% of 870 patients. Management changes with aPET were found in 72.2% of 740 cases and in 55.5% of 299 cases in the control group (p < 0.0001). The diagnostic value of aPET in AUC+ patients or when FDG/CSF were additionally available did not substantially differ from the value of aPET alone in the wider population. Amyloid PET contributed to diagnostic revision in almost a third of cases and demonstrated value in increasing diagnostic confidence and refining management plans.

A Systematic Review and Aggregated Analysis on the Impact of Amyloid PET Brain Imaging on the Diagnosis, Diagnostic Confidence, and Management of Patients being Evaluated for Alzheimer’s Disease

PubMed Central

Fantoni, Enrico R.; Chalkidou, Anastasia; O’ Brien, John T.; Farrar, Gill; Hammers, Alexander

2018-01-01

Background: Amyloid PET (aPET) imaging could improve patient outcomes in clinical practice, but the extent of impact needs quantification. Objective: To provide an aggregated quantitative analysis of the value added by aPET in cognitively impaired subjects. Methods: Systematic literature searches were performed in Embase and Medline until January 2017. 1,531 cases over 12 studies were included (1,142 cases over seven studies in the primary analysis where aPET was the key biomarker; the remaining cases included as defined groups in the secondary analysis). Data was abstracted by consensus among two observers and assessed for bias. Clinical utility was measured by diagnostic change, diagnostic confidence, and patient management before and after aPET. Three groups were further analyzed: control patients for whom feedback of aPET scan results was delayed; aPET Appropriate Use Criteria (AUC+) cases; and patients undergoing additional FDG/CSF testing. Results: For 1,142 cases with only aPET, 31.3% of diagnoses were revised, whereas 3.2% of diagnoses changed in the delayed aPET control group (p < 0.0001). Increased diagnostic confidence following aPET was found for 62.1% of 870 patients. Management changes with aPET were found in 72.2% of 740 cases and in 55.5% of 299 cases in the control group (p < 0.0001). The diagnostic value of aPET in AUC+ patients or when FDG/CSF were additionally available did not substantially differ from the value of aPET alone in the wider population. Conclusions: Amyloid PET contributed to diagnostic revision in almost a third of cases and demonstrated value in increasing diagnostic confidence and refining management plans. PMID:29689725

Empirical performance of the calibrated self-controlled cohort analysis within temporal pattern discovery: lessons for developing a risk identification and analysis system.

PubMed

Norén, G Niklas; Bergvall, Tomas; Ryan, Patrick B; Juhlin, Kristina; Schuemie, Martijn J; Madigan, David

2013-10-01

Observational healthcare data offer the potential to identify adverse drug reactions that may be missed by spontaneous reporting. The self-controlled cohort analysis within the Temporal Pattern Discovery framework compares the observed-to-expected ratio of medical outcomes during post-exposure surveillance periods with those during a set of distinct pre-exposure control periods in the same patients. It utilizes an external control group to account for systematic differences between the different time periods, thus combining within- and between-patient confounder adjustment in a single measure. To evaluate the performance of the calibrated self-controlled cohort analysis within Temporal Pattern Discovery as a tool for risk identification in observational healthcare data. Different implementations of the calibrated self-controlled cohort analysis were applied to 399 drug-outcome pairs (165 positive and 234 negative test cases across 4 health outcomes of interest) in 5 real observational databases (four with administrative claims and one with electronic health records). Performance was evaluated on real data through sensitivity/specificity, the area under receiver operator characteristics curve (AUC), and bias. The calibrated self-controlled cohort analysis achieved good predictive accuracy across the outcomes and databases under study. The optimal design based on this reference set uses a 360 days surveillance period and a single control period 180 days prior to new prescriptions. It achieved an average AUC of 0.75 and AUC >0.70 in all but one scenario. A design with three separate control periods performed better for the electronic health records database and for acute renal failure across all data sets. The estimates for negative test cases were generally unbiased, but a minor negative bias of up to 0.2 on the RR-scale was observed with the configurations using multiple control periods, for acute liver injury and upper gastrointestinal bleeding. The calibrated self-controlled cohort analysis within Temporal Pattern Discovery shows promise as a tool for risk identification; it performs well at discriminating positive from negative test cases. The optimal parameter configuration may vary with the data set and medical outcome of interest.

Contracting for Navy Husbanding Services: An Analysis of the Fat Leonard Case

DTIC Science & Technology

2017-12-01

management and internal control frameworks. This research analyzes each alleged act of fraud in the Fat Leonard case and aligns the act with the contract...management phase in which the alleged act occurred and with the internal control component that most contributed to and allowed the alleged act to be...contract administration phases. Furthermore, the findings indicate that the internal control deficiencies were in the control environment and

Common variation near CDKN1A, POLD3 and SHROOM2 influences colorectal cancer risk.

PubMed

Dunlop, Malcolm G; Dobbins, Sara E; Farrington, Susan Mary; Jones, Angela M; Palles, Claire; Whiffin, Nicola; Tenesa, Albert; Spain, Sarah; Broderick, Peter; Ooi, Li-Yin; Domingo, Enric; Smillie, Claire; Henrion, Marc; Frampton, Matthew; Martin, Lynn; Grimes, Graeme; Gorman, Maggie; Semple, Colin; Ma, Yusanne P; Barclay, Ella; Prendergast, James; Cazier, Jean-Baptiste; Olver, Bianca; Penegar, Steven; Lubbe, Steven; Chander, Ian; Carvajal-Carmona, Luis G; Ballereau, Stephane; Lloyd, Amy; Vijayakrishnan, Jayaram; Zgaga, Lina; Rudan, Igor; Theodoratou, Evropi; Starr, John M; Deary, Ian; Kirac, Iva; Kovacević, Dujo; Aaltonen, Lauri A; Renkonen-Sinisalo, Laura; Mecklin, Jukka-Pekka; Matsuda, Koichi; Nakamura, Yusuke; Okada, Yukinori; Gallinger, Steven; Duggan, David J; Conti, David; Newcomb, Polly; Hopper, John; Jenkins, Mark A; Schumacher, Fredrick; Casey, Graham; Easton, Douglas; Shah, Mitul; Pharoah, Paul; Lindblom, Annika; Liu, Tao; Smith, Christopher G; West, Hannah; Cheadle, Jeremy P; Midgley, Rachel; Kerr, David J; Campbell, Harry; Tomlinson, Ian P; Houlston, Richard S

2012-05-27

We performed a meta-analysis of five genome-wide association studies to identify common variants influencing colorectal cancer (CRC) risk comprising 8,682 cases and 9,649 controls. Replication analysis was performed in case-control sets totaling 21,096 cases and 19,555 controls. We identified three new CRC risk loci at 6p21 (rs1321311, near CDKN1A; P = 1.14 × 10(-10)), 11q13.4 (rs3824999, intronic to POLD3; P = 3.65 × 10(-10)) and Xp22.2 (rs5934683, near SHROOM2; P = 7.30 × 10(-10)) This brings the number of independent loci associated with CRC risk to 20 and provides further insight into the genetic architecture of inherited susceptibility to CRC.

Association between autism and variants in the wingless-type MMTV integration site family member 2 ( WNT2) gene.

PubMed

Marui, Tetsuya; Funatogawa, Ikuko; Koishi, Shinko; Yamamoto, Kenji; Matsumoto, Hideo; Hashimoto, Ohiko; Jinde, Seiichiro; Nishida, Hisami; Sugiyama, Toshiro; Kasai, Kiyoto; Watanabe, Keiichiro; Kano, Yukiko; Kato, Nobumasa

2010-05-01

Autism is a severe neurodevelopmental disorder with a complex genetic aetiology. The wingless-type MMTV integration site family member 2 (WNT2) gene has been considered as a candidate gene for autism. We conducted a case-control study and followed up with a transmission disequilibrium test (TDT) analysis to confirm replication of the significant results for the first time. We conducted a case-control study of nine single nucleotide polymorphisms (SNPs) within the WNT2 gene in 170 patients with autism and 214 normal controls in a Japanese population. We then conducted a TDT analysis in 98 autistic families (trios) to replicate the results of the case-control study. In the case-control study, three SNPs (rs3779547, rs4727847 and rs3729629), two major individual haplotypes (A-T-C and G-G-G, consisting of rs3779547, rs4727847, and rs3729629), and global probability values of the haplotype distributions in the same region (global p=0.0091) showed significant associations with autism. Furthermore, all of these significant associations were also observed in the TDT analysis. Our findings provide evidence for a significant association between WNT2 and autism. Considering the important role of the WNT2 gene in brain development, our results therefore indicate that the WNT2 gene is one of the strong candidate genes for autism.

Complement Factor D in Age-Related Macular Degeneration

PubMed Central

Stanton, Chloe M.; Yates, John R.W.; den Hollander, Anneke I.; Seddon, Johanna M.; Swaroop, Anand; Stambolian, Dwight; Fauser, Sascha; Hoyng, Carel; Yu, Yi; Atsuhiro, Kanda; Branham, Kari; Othman, Mohammad; Chen, Wei; Kortvely, Elod; Chalmers, Kevin; Hayward, Caroline; Moore, Anthony T.; Dhillon, Baljean; Ueffing, Marius

2011-01-01

Purpose. To examine the role of complement factor D (CFD) in age-related macular degeneration (AMD) by analysis of genetic association, copy number variation, and plasma CFD concentrations. Methods. Single nucleotide polymorphisms (SNPs) in the CFD gene were genotyped and the results analyzed by binary logistic regression. CFD gene copy number was analyzed by gene copy number assay. Plasma CFD was measured by an enzyme-linked immunosorbent assay. Results. Genetic association was found between CFD gene SNP rs3826945 and AMD (odds ratio 1.44; P = 0.028) in a small discovery case-control series (462 cases and 325 controls) and replicated in a combined cohorts meta-analysis of 4765 cases and 2693 controls, with an odds ratio of 1.11 (P = 0.032), with the association almost confined to females. Copy number variation in the CFD gene was identified in 13 out of 640 samples examined but there was no difference in frequency between AMD cases (1.3%) and controls (2.7%). Plasma CFD concentration was measured in 751 AMD cases and 474 controls and found to be elevated in AMD cases (P = 0.00025). The odds ratio for those in the highest versus lowest quartile for plasma CFD was 1.81. The difference in plasma CFD was again almost confined to females. Conclusions. CFD regulates activation of the alternative complement pathway, which is implicated in AMD pathogenesis. The authors found evidence for genetic association between a CFD gene SNP and AMD and a significant increase in plasma CFD concentration in AMD cases compared with controls, consistent with a role for CFD in AMD pathogenesis. PMID:22003108

Impact of traumatic dental injury on the quality of life of young children: a case-control study.

PubMed

Vieira-Andrade, Raquel Gonçalves; Siqueira, Maria Betânia Lins; Gomes, Genara Brum; D'Avila, Sérgio; Pordeus, Isabela Almeida; Paiva, Saul Martins; Granville-Garcia, Ana Flávia

2015-10-01

There are no longitudinal studies that assess the impact of traumatic dental injury (TDI) on the oral health-related quality of life (OHRQoL) of preschool children. To investigate the impact of TDI on OHRQoL among preschool children, a population-based case-control study was carried out with a representative sample of 335 children, 3-5 years of age, enrolled at public and private preschools in the city of Campina Grande, Brazil. The case group and the control group were matched for age, gender, type of preschool and monthly household income at a ratio of 1:4 (67 cases and 286 controls). Impact on the OHRQoL of children was assessed through administration of the Early Childhood Oral Health Impact Scale (ECOHIS). The occurrence of TDI was determined through clinical examinations performed by three calibrated dentists. Data analysis involved descriptive statistics, McNemar's test, the chi-square test with linear trend and conditional logistic regression analysis [P≤0.05; 95% confidence interval (95% CI)]. The most frequent responses were 'felt pain' (19.4%) and 'difficulty eating' (16.4%). The prevalence of TDI was 37.3% in the case group and 33.9% in the control group. No statistically significant differences were found between case and control groups regarding the presence of TDI (odds ratio=1.16; 95% CI: 0.66-2.02). TDI had no impact on the quality of life of preschool children. © 2015 FDI World Dental Federation.

A population-based study on the association between chronic periodontitis and sialolithiasis.

PubMed

Hung, Shih-Han; Huang, Hung-Meng; Lee, Hsin-Chien; Ching Lin, Herng; Kao, Li-Ting; Wu, Chuan-Song

2016-04-01

Whereas the impression that poor oral hygiene is linked to the development of sialolithiasis may be widely accepted, very few studies provide evidence to support this. This study therefore aimed to evaluate the association between chronic periodontitis (CP) and the subsequent development of salivary gland stone based on a nationwide coverage database. A case-control study. A total of 987 subjects with sialolithiasis were included as cases. In a ratio of five controls per case, 4,935 controls matched in terms of sex and age group were selected. Conditional logistic regression analysis was performed to determine the possible association of sialolithiasis with previously diagnosed CP. The prevalence of prior CP between cases and controls demonstrated that 1,831 (30.9%) out of the 5,922 sampled subjects had prior CP. By Chi-square test, there was a significant difference in the prevalence of prior CP between the cases and controls (36.8% vs. 29.7%, P < 0.001). By conditional logistic regression analysis, the odds ratio (OR) of prior CP for cases was 1.37 (95% confidence interval [CI], 1.19-1.56) compared to the controls after adjusting for geographic location and tobacco use. Further analyzing the relationship between sialolithiasis and prior CP according to sex, sialolithiasis was associated with prior CP regardless of sex. The adjusted OR of prior CP for the cases was 1.34 (95% CI, 1.10-1.64) and 1.41 (95% CI, 1.15-1.73) for males and females, respectively, when compared to controls. This study demonstrates an association between CP and sialolithiasis. 3b. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

Investigation of a national outbreak of STEC Escherichia coli O157 using online consumer panel control methods: Great Britain, October 2014.

PubMed

Sinclair, C; Jenkins, C; Warburton, F; Adak, G K; Harris, J P

2017-04-01

In October 2014, Public Health England (PHE) identified cases of Shiga toxin-producing Escherichia coli (STEC) serogroup O157 sharing a multiple locus variable-number tandem repeat analysis (MLVA) profile. We conducted a case-control study using multivariable logistic regression to calculate adjusted odds ratios (aOR) and 95% confidence intervals (CI) testing a range of exposures. Cases were defined as laboratory-confirmed STEC O157 with the implicated MLVA profile, were UK residents aged ⩾18 years with symptom onset between 25 September and 30 October 2014, and had no history of travel abroad within 5 days of symptom onset. One hundred and two cases were identified. Cases were mostly female (65%; median age 49, range 2-92 years). It was the second largest outbreak seen in England, to date, and a case-control study was conducted using market research panel controls and online survey methods. These methods were instrumental in the rapid data collection and analysis necessary to allow traceback investigations for short shelf-life products. This is a new method of control recruitment and this is the first in which it was a standalone recruitment method. The case-control study suggested a strong association between consumption of a ready-to-eat food and disease (aOR 28, 95% CI 5·0-157) from one retailer. No reactive microbiological testing of food items during the outbreak was possible due to the short shelf-life of the product. Collaboration with industrial bodies is needed to ensure timely traceback exercises to identify contamination events and initiate appropriate and focused microbiological testing and implement control measures.

Comments on: blood product transfusion in emergency department patients: a case control study of practice patterns and impact on outcome.

PubMed

Karami, Manoochehr; Khazaei, Salman

2017-12-06

Clinical decision makings according studies result require the valid and correct data collection, andanalysis. However, there are some common methodological and statistical issues which may ignore by authors. In individual matched case- control design bias arising from the unconditional analysis instead of conditional analysis. Using an unconditional logistic for matched data causes the imposition of a large number of nuisance parameters which may result in seriously biased estimates.

A Preliminary Study of Pneumonia Etiology Among Hospitalized Children in Kenya

PubMed Central

Kazungu, Sidi; Morpeth, Susan C.; Gibson, Dustin G.; Mvera, Benedict; Brent, Andrew J.; Mwarumba, Salim; Onyango, Clayton O.; Bett, Anne; Akech, Donald O.; Murdoch, David R.; Nokes, D. James; Scott, J. Anthony G.

2012-01-01

Background. Pneumonia is the leading cause of childhood death in the developing world. Higher-quality etiological data are required to reduce this mortality burden. Methods. We conducted a case-control study of pneumonia etiology among children aged 1–59 months in rural Kenya. Case patients were hospitalized with World Health Organization–defined severe pneumonia (SP) or very severe pneumonia (VSP); controls were outpatient children without pneumonia. We collected blood for culture, induced sputum for culture and multiplex polymerase chain reaction (PCR), and obtained oropharyngeal swab specimens for multiplex PCR from case patients, and serum for serology and nasopharyngeal swab specimens for multiplex PCR from case patients and controls. Results. Of 984 eligible case patients, 810 (84%) were enrolled in the study; 232 (29%) had VSP. Blood cultures were positive in 52 of 749 case patients (7%). A predominant potential pathogen was identified in sputum culture in 70 of 417 case patients (17%). A respiratory virus was detected by PCR from nasopharyngeal swab specimens in 486 of 805 case patients (60%) and 172 of 369 controls (47%). Only respiratory syncytial virus (RSV) showed a statistically significant association between virus detection in the nasopharynx and pneumonia hospitalization (odds ratio, 12.5; 95% confidence interval, 3.1–51.5). Among 257 case patients in whom all specimens (excluding serum specimens) were collected, bacteria were identified in 24 (9%), viruses in 137 (53%), mixed viral and bacterial infection in 39 (15%), and no pathogen in 57 (22%); bacterial causes outnumbered viral causes when the results of the case-control analysis were considered. Conclusions. A potential etiology was detected in >75% of children admitted with SP or VSP. Except for RSV, the case-control analysis did not detect an association between viral detection in the nasopharynx and hospitalization for pneumonia. PMID:22403235

Bridging ImmunoGenomic Data Analysis Workflow Gaps (BIGDAWG): An integrated case-control analysis pipeline.

PubMed

Pappas, Derek J; Marin, Wesley; Hollenbach, Jill A; Mack, Steven J

2016-03-01

Bridging ImmunoGenomic Data-Analysis Workflow Gaps (BIGDAWG) is an integrated data-analysis pipeline designed for the standardized analysis of highly-polymorphic genetic data, specifically for the HLA and KIR genetic systems. Most modern genetic analysis programs are designed for the analysis of single nucleotide polymorphisms, but the highly polymorphic nature of HLA and KIR data require specialized methods of data analysis. BIGDAWG performs case-control data analyses of highly polymorphic genotype data characteristic of the HLA and KIR loci. BIGDAWG performs tests for Hardy-Weinberg equilibrium, calculates allele frequencies and bins low-frequency alleles for k×2 and 2×2 chi-squared tests, and calculates odds ratios, confidence intervals and p-values for each allele. When multi-locus genotype data are available, BIGDAWG estimates user-specified haplotypes and performs the same binning and statistical calculations for each haplotype. For the HLA loci, BIGDAWG performs the same analyses at the individual amino-acid level. Finally, BIGDAWG generates figures and tables for each of these comparisons. BIGDAWG obviates the error-prone reformatting needed to traffic data between multiple programs, and streamlines and standardizes the data-analysis process for case-control studies of highly polymorphic data. BIGDAWG has been implemented as the bigdawg R package and as a free web application at bigdawg.immunogenomics.org. Copyright © 2015 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

Hypothyroidism among SLE patients: Case-control study.

PubMed

Watad, Abdulla; Mahroum, Naim; Whitby, Aaron; Gertel, Smadar; Comaneshter, Doron; Cohen, Arnon D; Amital, Howard

2016-05-01

The prevalence of hypothyroidism in SLE patients varies considerably and early reports were mainly based on small cohorts. To investigate the association between SLE and hypothyroidism. Patients with SLE were compared with age and sex-matched controls regarding the proportion of hypothyroidism in a case-control study. Chi-square and t-tests were used for univariate analysis and a logistic regression model was used for multivariate analysis. The study was performed utilizing the medical database of Clalit Health Services. The study included 5018 patients with SLE and 25,090 age and sex-matched controls. The proportion of hypothyroidism in patients with SLE was increased compared with the prevalence in controls (15.58% and 5.75%, respectively, P<0.001). In a multivariate analysis, SLE was associated with hypothyroidism (odds ratio 2.644, 95% confidence interval 2.405-2.908). Patients with SLE have a greater proportion of hypothyroidism than matched controls. Therefore, physicians treating patients with SLE should be aware of the possibility of thyroid dysfunction. Copyright © 2016 Elsevier B.V. All rights reserved.

Association between the rs1143634 polymorphism in interleukin-1B and chronic periodontitis: Results from a meta-analysis composed by 54 case/control studies.

PubMed

da Silva, Felipe Rodolfo Pereira; Vasconcelos, Any Carolina Cardoso Guimarães; de Carvalho França, Luiz Felipe; Di Lenardo, David; Nascimento, Hélio Mateus Silva; Vasconcelos, Daniel Fernando Pereira

2018-08-20

Several factors are involved in the periodontitis with host response through cytokines and as well as with influence of polymorphisms in cytokine genes, however the results remained contradictory. This study aimed at evaluating the rs1143634 polymorphism in interleukin-1B gene, a cytokine gene, and the risk of chronic periodontitis with conducting a meta-analysis focusing in ethnicity. A review in literature was performed in several databases to studies published before June 2017. Data extraction was performed by two calibrated investigators and the calculations of the meta-analysis were obtained through Review Manager version 5.2 statistical software with Odds Ratio (OR) calculation and Funnel plot (P < 0.05) to heterogeneity and the Comprehensive Meta-analysis version 3.3.070 to assessment publication bias by Egger's and Begg's tests. In overall, 54 case/control studies composed the meta-analysis. T allele was significantly associated with patients case (OR = 1.35, 95% CI: 1.24, 1.48, P < 0.00001) in the overall analysis. The stratified evaluation showed the rs1143634 polymorphism had significant association with disease in Caucasian, Asian and mixed population was excepted in African ethnicity (P > 0.05). No publication bias was found in allelic evaluation. This meta-analysis in 9376 participants with 54 case/control studies revealed the rs1143634 polymorphism was associated with elevated risk of chronic periodontitis in overall analysis as well as Caucasian and Asian ethnicities and Mixed population. Copyright © 2018 Elsevier B.V. All rights reserved.

Toxocara canis infection of children: epidemiologic and neuropsychologic findings.

PubMed Central

Marmor, M; Glickman, L; Shofer, F; Faich, L A; Rosenberg, C; Cornblatt, B; Friedman, S

1987-01-01

Sera from 4,652 children whose blood was submitted to the New York City Department of Health for lead analysis were tested for antibodies to Toxocara canis using an enzyme-linked immunosorbent assay (ELISA). Standardized to the age distribution of the study population, T. canis seropositivity (inverse titers greater than or equal to 16) was 5.7 per cent in males and 5.1 per cent in females. T. canis antibody titers and lead exposures as measured by Centers for Disease Control lead classes were positively correlated. Children who were seropositive to T. canis (cases) were compared to seronegatives (controls) matched on age (+/- 6 months), sex, time-of-screening (+/- 3 months) and CDC lead class. Logistic regression analysis of 155 case-control pairs demonstrated elevated relative risks (RRs) for geophagia (RR = 3.14; 95% CI = 1.75, 5.64) and having had a litter of puppies in the home (RR = 5.22; 95% CI = 1.63, 16.71). Compared to controls, cases had increased eosinophil counts, serum immunoglobulin E concentrations, and anti-hemagglutinin-A titers. Small deficits in cases compared to controls were found in performance on several neuropsychological tests after adjustment for potential confounders including case-control differences in race, socioeconomic status, and current blood lead concentrations. The study thus confirmed that T. canis infection is common in urban children and suggested that infection may be associated with adverse neuropsychological effects. PMID:3565646

Human Reliability Analysis in Support of Risk Assessment for Positive Train Control

DOT National Transportation Integrated Search

2003-06-01

This report describes an approach to evaluating the reliability of human actions that are modeled in a probabilistic risk assessment : (PRA) of train control operations. This approach to human reliability analysis (HRA) has been applied in the case o...

Alternative approaches to analytical designs in occupational injury epidemiology.

PubMed

Mittleman, M A; Maldonado, G; Gerberich, S G; Smith, G S; Sorock, G S

1997-08-01

In this paper, we discuss the theoretical framework upon which observational studies of occupational injuries are based. Following a general description of how causal effects are estimated, the challenges faced by researchers working in this area are outlined, with an emphasis on case-control studies. These challenges include defining the at-risk period for workers whose tasks change over time and whose hazard period may be very brief, evaluating the underreporting of both exposures and injuries, and considering the effects of multiple injuries per individual on study design and data analysis. We review both the theoretical and practical considerations in the design and conduct of traditional case-control studies, based on the collection of individual level data, as well as other approaches, such as using information culled from administrative and descriptive databases, and case-control studies in which the plant or work site is the unit of analysis. The case-crossover design is also reviewed and its utility for reducing confounding due to differences between individuals by self-matching is highlighted. While this design has not yet been applied to the work setting, its potential for increasing our understanding of the causes of acute-onset occupational injuries seems promising. Finally, a variety of hybrid designs are discussed, including combinations of case-control, case-crossover, and cohort designs.

Network-based regularization for matched case-control analysis of high-dimensional DNA methylation data.

PubMed

Sun, Hokeun; Wang, Shuang

2013-05-30

The matched case-control designs are commonly used to control for potential confounding factors in genetic epidemiology studies especially epigenetic studies with DNA methylation. Compared with unmatched case-control studies with high-dimensional genomic or epigenetic data, there have been few variable selection methods for matched sets. In an earlier paper, we proposed the penalized logistic regression model for the analysis of unmatched DNA methylation data using a network-based penalty. However, for popularly applied matched designs in epigenetic studies that compare DNA methylation between tumor and adjacent non-tumor tissues or between pre-treatment and post-treatment conditions, applying ordinary logistic regression ignoring matching is known to bring serious bias in estimation. In this paper, we developed a penalized conditional logistic model using the network-based penalty that encourages a grouping effect of (1) linked Cytosine-phosphate-Guanine (CpG) sites within a gene or (2) linked genes within a genetic pathway for analysis of matched DNA methylation data. In our simulation studies, we demonstrated the superiority of using conditional logistic model over unconditional logistic model in high-dimensional variable selection problems for matched case-control data. We further investigated the benefits of utilizing biological group or graph information for matched case-control data. We applied the proposed method to a genome-wide DNA methylation study on hepatocellular carcinoma (HCC) where we investigated the DNA methylation levels of tumor and adjacent non-tumor tissues from HCC patients by using the Illumina Infinium HumanMethylation27 Beadchip. Several new CpG sites and genes known to be related to HCC were identified but were missed by the standard method in the original paper. Copyright © 2012 John Wiley & Sons, Ltd.

High Spicy Food Intake and Risk of Cancer: A Meta-analysis of Case-control Studies.

PubMed

Chen, Yu-Heng; Zou, Xiao-Nong; Zheng, Tong-Zhang; Zhou, Qi; Qiu, Hui; Chen, Yuan-Li; He, Mei; Du, Jia; Lei, Hai-Ke; Zhao, Ping

2017-09-20

Studies on the association between spicy food intake and cancer risk have reported inconsistent results. We quantitatively assessed this association by conducting a meta-analysis based on evidence from case-control studies. PubMed, EMBASE, and the Cochrane Library were searched for eligible publications. Combined odds ratios (OR s) with their 95% confidence interval (CI) were calculated using a random- or fixed-effects model. The methodological quality of the included articles was assessed using the Newcastle-Ottawa scale (NOS). All data were analyzed using STATA 11.0 software (version 11.0; StataCorp., College Station, TX, USA). Subgroup analyses were also performed with stratification by region, sex, number of cases, cancer subtype, source of the control group, and NOS score. A total 39 studies from 28 articles fulfilled the inclusion criteria for the meta-analysis (7884 patients with cancer and 10,142 controls). Comparison of the highest versus lowest exposure category in each study revealed a significant OR of 1.76 (95% CI = 1.35-2.29) in spite of significant heterogeneity (P < 0.001). In the subgroup analyses, this positive correlation was still found for gastric cancer, different regions, different numbers of cases, different sources of the control group, and high-quality articles (NOS score of ≥ 7). However, no statistically significant association was observed for women, esophageal cancer, gallbladder cancer, or low-quality articles (NOS score of <7). No evidence of publication bias was found. Evidence from case-control studies suggested that a higher level of spicy food intake may be associated with an increased incidence of cancer despite significant heterogeneity. More studies are warranted to clarify our understanding of the association between high spicy food intake and the risk of cancer.

Common mental disorders associated with tuberculosis: a matched case-control study.

PubMed

de Araújo, Gleide Santos; Pereira, Susan Martins; dos Santos, Darci Neves; Marinho, Jamocyr Moura; Rodrigues, Laura Cunha; Barreto, Mauricio Lima

2014-01-01

Despite the availability of treatment and a vaccine, tuberculosis continues to be a public health problem worldwide. Mental disorders might contribute to the burden of the disease. The objective of this study was to investigate the association between common mental disorders and tuberculosis. A matched case-control study was conducted. The study population included symptomatic respiratory patients who attended three referral hospitals and six community clinics in the city of Salvador, Brazil. A doctor's diagnosis defined potential cases and controls. Cases were newly diagnosed tuberculosis cases, and controls were symptomatic respiratory patients for whom tuberculosis was excluded as a diagnosis by the attending physician. Cases and controls were ascertained in the same clinic. Data collection occurred between August 2008 and April 2010. The study instruments included a structured interview, a self-reporting questionnaire for the identification of common mental disorders, and a questionnaire for alcoholism. An univariate analysis included descriptive procedures (with chi-square statistics), and a multivariate analysis used conditional logistic regression. The mean age of the cases was 38 years, and 61% of the cases were males. After adjusting for potential confounders, the odds of tuberculosis were significantly higher in patients diagnosed with a common mental disorder (OR: 1.34; 95% CI 1.05-1.70). There appears to be a positive and independent association between common mental disorders and tuberculosis; further epidemiological studies are required to increase our understanding of the possible biological and social mechanisms responsible for this association. Independent of the direction of the association, this finding has implications for the provision of care for mental disorders and for tuberculosis.

Association of vitamin D receptor BsmI, TaqI, FokI, and ApaI polymorphisms with susceptibility of chronic periodontitis: A systematic review and meta-analysis based on 38 case -control studies.

PubMed

Mashhadiabbas, Fatemeh; Neamatzadeh, Hossein; Nasiri, Rezvan; Foroughi, Elnaz; Farahnak, Soudabeh; Piroozmand, Parisa; Mazaheri, Mahta; Zare-Shehneh, Masoud

2018-01-01

There has been increasing interest in the study of the association between Vitamin D receptor (VDR) gene polymorphisms and risk of chronic periodontitis. However, the results remain inconclusive. To better understand the roles of VDR polymorphisms (BsmI, TaqI, FokI, and ApaI) in chronic periodontitis susceptibility, we conducted this systematic review and meta-analysis. The PubMed, Google Scholar, and Web of Science database were systemically searched to determine all the eligible studies about VDR polymorphisms and risk of chronic periodontitis up to April 2017. Odds ratio (OR) and 95% confidence interval (CI) were used to evaluate the associations between VDR polymorphisms and chronic periodontitis risk. All the statistical analyses were performed by Comprehensive Meta-Analysis. All P values were two-tailed with a significant level at 0.05. Finally, a total of 38 case-control studies in 19 publications were identified which met our inclusion criteria. There are ten studies with 866 chronic periodontitis cases and 786 controls for BsmI, 16 studies with 1570 chronic periodontitis cases and 1676 controls for TaqI, five studies with 374 chronic periodontitis cases and 382 controls for FokI, and seven studies with 632 chronic periodontitis cases and 604 controls for ApaI. Overall, no significant association was observed between VDR gene BsmI, TaqI, FokI, and ApaI polymorphisms and risk of chronic periodontitis in any genetic model. Subgroup analysis stratified by ethnicity suggested a significant association between BsmI polymorphism and chronic periodontitis risk in the Caucasian subgroup under allele model (A vs. G: OR = 1.747, 95% CI = 1.099-2.778, P = 0.018). Further, no significant associations were observed when stratified by Hardy-Weinberg equilibrium status for BsmI, TaqI, and ApaI. Our results suggest that BsmI, TaqI, FokI, and ApaI polymorphisms in the VDR gene might not be associated with risk of chronic periodontitis in overall population.

Zinc Intake and Risk of Prostate Cancer: Case-Control Study and Meta-Analysis.

PubMed

Mahmoud, Abeer M; Al-Alem, Umaima; Dabbous, Firas; Ali, Mohamed M; Batai, Ken; Shah, Ebony; Kittles, Rick A

2016-01-01

Zinc is an essential dietary element that has been implicated in the pathogenesis of prostate cancer, a cancer that disproportionately affects men of African descent. Studies assessing the association of zinc intake and prostate cancer have yielded inconsistent results. Furthermore, very little is known about the relationship between zinc intake and prostate cancer among African Americans. We examined the association between self-reported zinc intake and prostate cancer in a hospital-based case-control study of African Americans. We then compared our results with previous studies by performing a meta-analysis to summarize the evidence regarding the association between zinc and prostate cancer. Newly diagnosed African American men with histologically confirmed prostate cancer (n = 127) and controls (n = 81) were recruited from an urban academic urology clinic in Washington, DC. Controls had higher zinc intake, with a mean of 14 mg/day versus 11 mg/day for cases. We observed a non-significant, non-linear increase in prostate cancer when comparing tertiles of zinc intake (OR <6.5 vs 6.5-12.5mg/day 1.8, 95% CI: 0.6,5.6; OR <6.5 vs >12.5mg/day 1.3, 95% CI: 0.2,6.5). The pooled estimate from 17 studies (including 3 cohorts, 2 nested case-control, 11 case-control studies, and 1 randomized clinical trial, with a total of 111,199 participants and 11,689 cases of prostate cancer) was 1.07hi vs lo 95% CI: 0.98-1.16. Using a dose-response meta-analysis, we observed a non-linear trend in the relationship between zinc intake and prostate cancer (p for nonlinearity = 0.0022). This is the first study to examine the relationship between zinc intake in black men and risk of prostate cancer and systematically evaluate available epidemiologic evidence about the magnitude of the relationship between zinc intake and prostate cancer. Despite of the lower intake of zinc by prostate cancer patients, our meta-analysis indicated that there is no evidence for an association between zinc intake and prostate cancer.

Evidence for rare and common genetic risk variants for schizophrenia at protein kinase C, alpha.

PubMed

Carroll, L S; Williams, N M; Moskvina, V; Russell, E; Norton, N; Williams, H J; Peirce, T; Georgieva, L; Dwyer, S; Grozeva, D; Greene, E; Farmer, A; McGuffin, P; Morris, D W; Corvin, A; Gill, M; Rujescu, D; Sham, P; Holmans, P; Jones, I; Kirov, G; Craddock, N; O'Donovan, M C; Owen, M J

2010-11-01

We earlier reported a genome-wide significant linkage to schizophrenia at chromosome 17 that was identified in a single pedigree (C702) consisting of six affected, male siblings with DSM-IV schizophrenia and prominent mood symptoms. In this study, we adopted several approaches in an attempt to map the putative disease locus. First, mapping the source of linkage to chromosome 17 in pedigree C702. We refined the linkage region in family C702 to a 21-marker segment spanning 11.7 Mb at 17q23-q24 by genotyping a total of 50 microsatellites across chromosome 17 in the pedigree. Analysis of data from 1028 single nucleotide polymorphisms (SNPs) across the refined linkage region identified a single region of homozygosity present in pedigree C702 but not in 2938 UK controls. This spanned ~432 kb of the gene encoding protein kinase C, alpha (PRKCA), the encoded protein of which has been implicated in the pathogenesis of psychiatric disorders. Analysis of pedigree C702 by oligonucleotide-array comparative genome hybridization excluded the possibility that this region of homozygosity was because of a deletion. Mutation screening of PRKCA identified a rare, four-marker haplotype (C-HAP) in the 3' untranslated region of the gene, which was present in the homozygous state in all six affected members of pedigree C702. No other homozygotes were observed in genotype data for a total of 6597 unrelated Europeans (case N=1755, control N=3580 and parents of probands N=1262). Second, association analysis of C702 alleles at PRKCA. The low-frequency haplotype (C-HAP) showed a trend for association in a study of unrelated schizophrenia cases and controls from the UK (661 cases, 2824 controls, P=0.078 and odd ratio (OR)=1.9) and significant evidence for association when the sample was expanded to include cases with bipolar (N=710) and schizoaffective disorder (N=50) (psychosis sample: 1421 cases, 2824 controls, P=0.037 and OR=1.9). Given that all the affected members of C702 are male, we also undertook sex-specific analyses. This revealed that the association was strongest in males for both schizophrenia (446 male cases, 1421 male controls, P=0.008 and OR=3.9) and in the broader psychosis group (730 male cases, 1421 male controls, P=0.008 and OR=3.6). Analysis of C-HAP in follow-up samples from Ireland and Bulgaria revealed no evidence for association in either the whole sample or in males alone, and meta-analysis of all male psychosis samples yielded no significant evidence of association (969 male cases, 1939 male controls, 311 male probands P=0.304 and OR=1.4). Third, association mapping of the pedigree C702 linkage region. Independent of pedigree C702, genotype data from the Affymetrix 500k GeneChip set were available for 476 patients with schizophrenia and 2938 controls from the United Kingdom. SNPs in PRKCA showed evidence for association with schizophrenia that achieved gene-wide significance (P=0.027). Moreover, the same SNP was the most significantly associated marker out of the 1028 SNPs genotyped across the linkage region (rs873417, allelic P=0.0004). Follow-up genotyping in samples from Ireland, Bulgaria and Germany did not show consistent replication, but meta-analysis of all samples (4116 cases and 6491 controls) remained nominally significant (meta-analysis P=0.026, OR=1.1). We conclude that, although we have obtained convergent lines of evidence implicating both rare and common schizophrenia risk variants at PRKCA, none of these is individually compelling. However, the evidence across all approaches suggests that further study of this locus is warranted.

Risk factors for epilepsy in Bas-Uélé Province, Democratic Republic of the Congo: a case-control study.

PubMed

Colebunders, Robert; Mandro, Michel; Mokili, John L; Mucinya, Gisele; Mambandu, Germain; Pfarr, Kenneth; Reiter-Owona, Ingrid; Hoerauf, Achim; Tepage, Floribert; Levick, Bethanie; Begon, Michael; Laudisoit, Anne

2016-08-01

The reason for the high prevalence of epilepsy in onchocerciasis endemic areas remains unknown. The aim of this study was to detect risk factors associated with epilepsy in a region endemic for onchocerciasis. In June 2014, a case-control study was performed in Titule, Bas-Uélé Province in the Democratic Republic of the Congo. Individuals with unprovoked convulsive epilepsy of unknown aetiology were enrolled as cases (n=59). Healthy members of families without cases of epilepsy in the same village were recruited as controls (n=61). A multivariate binomial logistic regression analysis was performed to identify potential risk factors associated with epilepsy. To evaluate the potential protective effect of ivermectin treatment on the development of epilepsy, a nested age-matched case-control study was performed including only those who were eligible for ivermectin treatment in the year before they developed epilepsy. Suspected onchocerciasis skin lesions were more often present in cases than in controls: 12/41 (29%) vs. 1/56 (2%), respectively (odds ratio (OR) 20.26, 95% confidence interval (CI) 2.42-170; p<0.01). Ivermectin had been taken 7 months earlier in 29/59 (49%) cases and 29/61 (48%) controls. Onchocerca volvulus (OV) DNA was detected by PCR in skin snips in 26/34 cases (76%) and 10/14 controls (71%) (p=0.7), and there was presence of OV IgG4 antibodies in 35/48 (73%) cases and 15/18 (83%) controls (p=0.5). OV DNA was not detected in the cerebrospinal fluid of cases (controls not tested). Both cases and controls reported frequent bites by blackflies (Diptera, Simuliidae). Bathing daily as opposed to less often (OR 16.7, 95% CI 2.2-125.8; p<0.01), bathing between 11 a.m. and 4 p.m. (OR 12.7, 95% CI 1.6-103.7; p=0.02), and washing clothes between 11 a.m. and 4 p.m. (OR 10.9, 95% CI 1.5-77.3; p=0.02) were all independently associated with epilepsy. Blood screening by specific PCR tests for Toxoplasma and Wuchereria bancrofti was negative in all cases and controls. A Loa loa infestation was found in only one case and one control by PCR and Giemsa smear. Antibodies to Taenia solium, Toxocara, and Trypanosoma sp were not detected in any of the participants. In an age-matched case-control analysis, 16/18 (89%) cases had not taken ivermectin the year before they developed epilepsy, compared to 7/18 (39%) controls that same year (p=0.002). These data suggest that frequent activities at rivers known to be blackfly breeding sites and a historical lack of ivermectin treatment were risk factors for epilepsy in this onchocerciasis endemic area. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Effectiveness of oral polio vaccination against paralytic poliomyelitis: a matched case-control study in Somalia.

PubMed

Mahamud, Abdirahman; Kamadjeu, Raoul; Webeck, Jenna; Mbaeyi, Chukwuma; Baranyikwa, Marie Therese; Birungi, Julianne; Nurbile, Yassin; Ehrhardt, Derek; Shukla, Hemant; Chatterjee, Anirban; Mulugeta, Abraham

2014-11-01

After the last case of type 1 wild poliovirus (WPV1) was reported in 2007, Somalia experienced another outbreak of WPV1 (189 cases) in 2013. We conducted a retrospective, matched case-control study to evaluate the vaccine effectiveness (VE) of oral polio vaccine (OPV). We retrieved information from the Somalia Surveillance Database. A case was defined as any case of acute flaccid paralysis (AFP) with virological confirmation of WPV1. We selected two groups of controls for each case: non-polio AFP cases ("NPAFP controls") matched to WPV1 cases by age, date of onset of paralysis and region; and asymptomatic "neighborhood controls," matched by age. Using conditional logistic regression, we estimated the VE of OPV as (1-odds ratio)×100. We matched 99 WPV cases with 99 NPAFP controls and 134 WPV1 cases with 268 neighborhood controls. Using NPAFP controls, the overall VE was 70% (95% confidence interval [CI], 37-86), 59% (2-83) among 1-3 dose recipients, 77% (95% CI, 46-91) among ≥4 dose recipients. In neighborhood controls, the overall VE was 95% (95% CI, 84-98), 92% (72-98) among 1-3 dose recipients, and 97% (89-99) among ≥4 dose recipients. When the analysis was limited to cases and controls ≤24 months old, the overall VE in NPAFP and neighborhood controls was 95% (95% CI, 65-99) and 97% (95% CI, 76-100), respectively. Among individuals who were fully vaccinated with OPV, vaccination was effective at preventing WPV1 in Somalia. Published by Oxford University Press on behalf of the Infectious Diseases Society of America 2014. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Breast Cancer and Modifiable Lifestyle Factors in Argentinean Women: Addressing Missing Data in a Case-Control Study

PubMed Central

Coquet, Julia Becaria; Tumas, Natalia; Osella, Alberto Ruben; Tanzi, Matteo; Franco, Isabella; Diaz, Maria Del Pilar

2016-01-01

A number of studies have evidenced the effect of modifiable lifestyle factors such as diet, breastfeeding and nutritional status on breast cancer risk. However, none have addressed the missing data problem in nutritional epidemiologic research in South America. Missing data is a frequent problem in breast cancer studies and epidemiological settings in general. Estimates of effect obtained from these studies may be biased, if no appropriate method for handling missing data is applied. We performed Multiple Imputation for missing values on covariates in a breast cancer case-control study of Córdoba (Argentina) to optimize risk estimates. Data was obtained from a breast cancer case control study from 2008 to 2015 (318 cases, 526 controls). Complete case analysis and multiple imputation using chained equations were the methods applied to estimate the effects of a Traditional dietary pattern and other recognized factors associated with breast cancer. Physical activity and socioeconomic status were imputed. Logistic regression models were performed. When complete case analysis was performed only 31% of women were considered. Although a positive association of Traditional dietary pattern and breast cancer was observed from both approaches (complete case analysis OR=1.3, 95%CI=1.0-1.7; multiple imputation OR=1.4, 95%CI=1.2-1.7), effects of other covariates, like BMI and breastfeeding, were only identified when multiple imputation was considered. A Traditional dietary pattern, BMI and breastfeeding are associated with the occurrence of breast cancer in this Argentinean population when multiple imputation is appropriately performed. Multiple Imputation is suggested in Latin America’s epidemiologic studies to optimize effect estimates in the future. PMID:27892664

Recovery of divergent avian bornaviruses from cases of proventricular dilatation disease: Identification of a candidate etiologic agent

PubMed Central

Kistler, Amy L; Gancz, Ady; Clubb, Susan; Skewes-Cox, Peter; Fischer, Kael; Sorber, Katherine; Chiu, Charles Y; Lublin, Avishai; Mechani, Sara; Farnoushi, Yigal; Greninger, Alexander; Wen, Christopher C; Karlene, Scott B; Ganem, Don; DeRisi, Joseph L

2008-01-01

Background Proventricular dilatation disease (PDD) is a fatal disorder threatening domesticated and wild psittacine birds worldwide. It is characterized by lymphoplasmacytic infiltration of the ganglia of the central and peripheral nervous system, leading to central nervous system disorders as well as disordered enteric motility and associated wasting. For almost 40 years, a viral etiology for PDD has been suspected, but to date no candidate etiologic agent has been reproducibly linked to the disease. Results Analysis of 2 PDD case-control series collected independently on different continents using a pan-viral microarray revealed a bornavirus hybridization signature in 62.5% of the PDD cases (5/8) and none of the controls (0/8). Ultra high throughput sequencing was utilized to recover the complete viral genome sequence from one of the virus-positive PDD cases. This revealed a bornavirus-like genome organization for this agent with a high degree of sequence divergence from all prior bornavirus isolates. We propose the name avian bornavirus (ABV) for this agent. Further specific ABV PCR analysis of an additional set of independently collected PDD cases and controls yielded a significant difference in ABV detection rate among PDD cases (71%, n = 7) compared to controls (0%, n = 14) (P = 0.01; Fisher's Exact Test). Partial sequence analysis of a total of 16 ABV isolates we have now recovered from these and an additional set of cases reveals at least 5 distinct ABV genetic subgroups. Conclusion These studies clearly demonstrate the existence of an avian reservoir of remarkably diverse bornaviruses and provide a compelling candidate in the search for an etiologic agent of PDD. PMID:18671869

Outbreak of hepatitis A in two federal states of Germany: bakery products as vehicle of infection.

PubMed

Schenkel, K; Bremer, V; Grabe, C; Van Treeck, U; Schreier, E; Höhne, M; Ammon, A; Alpers, K

2006-12-01

In April 2004, increased numbers of hepatitis A were noted in six neighbouring districts in Germany. Exploratory interviews showed that patients had consumed bakery products from company X where two employees had been diagnosed with hepatitis A in February. A case-control study of consumption of products of company X was carried out through telephone interviews. Altogether, 64 cases were identified. Fifty-two cases and 112 controls aged >or=16 years were included in the case-control study. In total, 46/52 cases and 37/112 controls had consumed company X products [odds ratio (OR) 15.5, 95% confidence interval (CI) 6.1-39.7]. Of these, 36/46 cases and 16/37 controls had consumed pastries (OR 4.7, 95% CI 1.8-12.3), 25/46 cases and 12/37 controls had consumed filled doughnuts (OR 2.5, 95% CI 1.0-6.1). Sequence analysis of the VP1-2A junction region indicated 100% strain homology between cases and an infected employee of company X. We recommended reinforcement of hygiene precautions, and consideration of a prolongation of compulsory work absence after post-exposure vaccination.

Exposure to pesticides as risk factor for non-Hodgkin's lymphoma and hairy cell leukemia: pooled analysis of two Swedish case-control studies.

PubMed

Hardell, Lennart; Eriksson, Mikael; Nordstrom, Marie

2002-05-01

Increased risk for non-Hodgkin's lymphoma (NHL) following exposure to certain pesticides has previously been reported. To further elucidate the importance of phenoxyacetic acids and other pesticides in the etiology of NHL a pooled analysis was performed on two case-control studies, one on NHL and another on hairy cell leukemia (HCL), a rare subtype of NHL. The studies were population based with cases identified from cancer registry and controls from population registry. Data assessment was ascertained by questionnaires supplemented over the telephone by specially trained interviewers. The pooled analysis of NHL and HCL was based on 515 cases and 1141 controls. Increased risks in univariate analysis were found for subjects exposed to herbicides (OR 1.75, CI 95% 1.26-2.42), insecticides (OR 1.43, CI 95% 1.08-1.87), fungicides (OR 3.11, CI 95% 1.56-6.27) and impregnating agents (OR 1.48, CI 95% 1.11-1.96). Among herbicides, significant associations were found for glyphosate (OR 3.04, CI 95% 1.08-8.52) and 4-chloro-2-methyl phenoxyacetic acid (MCPA) (OR 2.62, CI 95% 1.40-4.88). For several categories of pesticides the highest risk was found for exposure during the latest decades before diagnosis. However, in multivariate analyses the only significantly increased risk was for a heterogeneous category of other herbicides than above.

Distributed environmental control

NASA Technical Reports Server (NTRS)

Cleveland, Gary A.

1992-01-01

We present an architecture of distributed, independent control agents designed to work with the Computer Aided System Engineering and Analysis (CASE/A) simulation tool. CASE/A simulates behavior of Environmental Control and Life Support Systems (ECLSS). We describe a lattice of agents capable of distributed sensing and overcoming certain sensor and effector failures. We address how the architecture can achieve the coordinating functions of a hierarchical command structure while maintaining the robustness and flexibility of independent agents. These agents work between the time steps of the CASE/A simulation tool to arrive at command decisions based on the state variables maintained by CASE/A. Control is evaluated according to both effectiveness (e.g., how well temperature was maintained) and resource utilization (the amount of power and materials used).

A Meta-Analysis Comparing Liposomal Bupivacaine and Traditional Periarticular Injection for Pain Control after Total Knee Arthroplasty.

PubMed

Sun, Hao; Huang, Zhiyu; Zhang, Zhiqi; Liao, Weiming

2018-04-04

Liposomal bupivacaine is a novel method for pain control after total knee arthroplasty (TKA), but recent studies showed no advantage for patients undergoing TKA compared with traditional periarticular injection (PAI). The purpose of this analysis was to compare the clinical outcomes between liposomal bupivacaine treatment and traditional PAI. We retrospectively reviewed data from 16 clinical trials in published databases from their inception to June 2017. The primary outcome was postoperative Visual Analogue Scale (VAS) score and secondary outcomes included opiate usage, narcotic consumption, range of motion, and length of stay. Nine randomized controlled trials and seven nonrandomized controlled trials involving 924 liposomal bupivacaine cases and 1,293 traditional PAI cases were eligible for inclusion in the meta-analysis. No differences were detected in most of the clinical outcomes, except for postoperative VAS within 12 hours and length of stay. This analysis showed that liposomal bupivacaine is not associated with significant improvement in postoperative pain control or other outcomes in TKA compared with PAI. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Common variation near CDKN1A, POLD3 and SHROOM2 influences colorectal cancer risk

PubMed Central

Dunlop, Malcolm G; Dobbins, Sara E; Farrington, Susan Mary; Jones, Angela M; Palles, Claire; Whiffin, Nicola; Tenesa, Albert; Spain, Sarah; Broderick, Peter; Ooi, Li-Yin; Domingo, Enric; Smillie, Claire; Henrion, Marc; Frampton, Matthew; Martin, Lynn; Grimes, Graeme; Gorman, Maggie; Semple, Colin; Ma, Yussanne; Barclay, Ella; Prendergast, James; Cazier, Jean-Baptiste; Olver, Bianca; Carvajal-Carmona, Luis G; Ballereau, Stephane; Lloyd, Amy; Vijayakrishnan, Jayaram; Zgaga, Lina; Rudan, Igor; Theodoratou, Evropi; Starr, John M; Deary, Ian; Kirac, Iva; Kovačević, Dujo; Aaltonen, Lauri A; Renkonen-Sinisalo, Laura; Mecklin, Jukka-Pekka; Matsuda, Koichi; Nakamura, Yusuke; Okada, Yukinori; Gallinger, Steven; Duggan, David J; Conti, David; Newcomb, Polly; Hopper, John; Jenkins, Mark A.; Schumacher, Fredrick; Casey, Graham; Easton, Douglas; Shah, Mitul; Pharoah, Paul; Lindblom, Annika; Liu, Tao; Smith, Christopher G; West, Hannah; Cheadle, Jeremy P.; Midgley, Rachel; Kerr, David J; Campbell, Harry; Tomlinson, Ian P; Houlston, Richard S

2015-01-01

We performed a meta-analysis of five genome-wide association studies to identify common variants influencing colorectal cancer (CRC) risk comprising 8,682 cases and 9,649 controls. Replication analysis was performed in case-control sets totalling 21,096 cases and 19,555 controls. We identified three novel CRC risk loci at 6p21 (rs1321311, near CDKN1A; P=1.14×10−10), 11q13.4 (rs3824999, intronic to POLD3; P=3.65×10−10) and Xp22.2 (rs5934683, near SHROOM2; P=7.30×10−10) This brings to 20 the number of independent loci associated with CRC risk, and provides further insight into the genetic architecture of inherited susceptibility to CRC. PMID:22634755

Methodological Issues in Design and Analysis of a Matched Case-Control Study of a Vaccine’s Effectiveness

PubMed Central

Niccolai, Linda M.; Ogden, Lorraine G.; Muehlenbein, Catherine E.; Dziura, James D.; Vázquez, Marietta; Shapiro, Eugene D.

2007-01-01

Objective Case-control studies of the effectiveness of a vaccine are useful to answer important questions, such as the effectiveness of a vaccine over time, that usually are not addressed by pre-licensure clinical trials of the vaccine’s efficacy. This report describes methodological issues related to design and analysis that were used to determine the effects of time since vaccination and age at the time of vaccination. Study Design and Setting A matched case-control study of the effectiveness of varicella vaccine. Results Sampling procedures and conditional logistic regression models including interaction terms are described. Conclusion Use of these methods will allow investigators to assess the effects of a wide range of variables, such as time since vaccination and age at the time of vaccination, on the effectiveness of a vaccine. PMID:17938054

Stability analysis via the concept of Lyapunov exponents: a case study in optimal controlled biped standing

NASA Astrophysics Data System (ADS)

Sun, Yuming; Wu, Christine Qiong

2012-12-01

Balancing control is important for biped standing. In spite of large efforts, it is very difficult to design balancing control strategies satisfying three requirements simultaneously: maintaining postural stability, improving energy efficiency and satisfying the constraints between the biped feet and the ground. In this article, a proportional-derivative (PD) controller is proposed for a standing biped, which is simplified as a two-link inverted pendulum with one additional rigid foot-link. The genetic algorithm (GA) is used to search for the control gain meeting all three requirements. The stability analysis of such a deterministic biped control system is carried out using the concept of Lyapunov exponents (LEs), based on which, the system stability, where the disturbance comes from the initial states, and the structural stability, where the disturbance comes from the PD gains, are examined quantitively in terms of stability region. This article contributes to the biped balancing control, more significantly, the method shown in the studied case of biped provides a general framework of systematic stability analysis for certain deterministic nonlinear dynamical systems.

Multiple-function multi-input/multi-output digital control and on-line analysis

NASA Technical Reports Server (NTRS)

Hoadley, Sherwood T.; Wieseman, Carol D.; Mcgraw, Sandra M.

1992-01-01

The design and capabilities of two digital controller systems for aeroelastic wind-tunnel models are described. The first allowed control of flutter while performing roll maneuvers with wing load control as well as coordinating the acquisition, storage, and transfer of data for on-line analysis. This system, which employs several digital signal multi-processor (DSP) boards programmed in high-level software languages, is housed in a SUN Workstation environment. A second DCS provides a measure of wind-tunnel safety by functioning as a trip system during testing in the case of high model dynamic response or in case the first DCS fails. The second DCS uses National Instruments LabVIEW Software and Hardware within a Macintosh environment.

Association between physical activity and risk of nonalcoholic fatty liver disease: a meta-analysis.

PubMed

Qiu, Shanhu; Cai, Xue; Sun, Zilin; Li, Ling; Zügel, Martina; Steinacker, Jürgen Michael; Schumann, Uwe

2017-09-01

Increased physical activity (PA) is a key element in the management of patients with nonalcoholic fatty liver disease (NAFLD); however, its association with NAFLD risk has not been systematically assessed. This meta-analysis of observational studies was to quantify this association with dose-response analysis. Electronic databases were searched to January 2017 for studies of adults reporting the risk of NAFLD in relation to PA with cohort or case-control designs. Studies that reported sex-specific data were included as separate studies. The overall risk estimates were pooled using a random-effects model, and the dose-response analysis was conducted to shape the quantitative relationship. A total of 6 cohort studies from 5 articles with 32,657 incident NAFLD cases from 142,781 participants, and 4 case-control studies from 3 articles with 382 NAFLD cases and 302 controls were included. Compared with the lowest PA level, the highest PA level was associated with a risk reduction of NAFLD in cohort [RR (risk ratio) 0.79, 95% CI (confidence interval) 0.71-0.89] and case-control studies [OR (odds ratio) 0.43, 95% CI 0.27-0.68]. For cohort studies, both highest and moderate PA levels were superior to the light one in lowering NAFLD risk ( p for interaction = 0.006 and 0.02, respectively), and there was a log-linear dose-response association ( p for nonlinearity = 0.10) between PA and NAFLD risk [RR 0.82 (95% CI 0.73-0.91) for every 500 metabolic equivalent (MET)-minutes/week increment in PA]. Increased PA may lead to a reduced risk of NAFLD in a dose-dependent manner, and the current guideline-recommended minimum PA level that approximates to 500 MET-minutes/week is able to moderately reduce the NAFLD risk.

Blood harmane (1-methyl-9H-pyrido[3,4-b]indole) concentration in essential tremor cases in Spain.

PubMed

Louis, Elan D; Benito-León, Julian; Moreno-García, Sara; Vega, Saturio; Romero, Juan Pablo; Bermejo-Pareja, Felix; Gerbin, Marina; Viner, Amanda S; Factor-Litvak, Pam; Jiang, Wendy; Zheng, Wei

2013-01-01

Environmental correlates for essential tremor (ET) are largely unexplored. The search for such environmental factors has involved the study of a number of neurotoxins. Harmane (1-methyl-9H-pyrido[3,4-b]indole) is a potent tremor-producing toxin. In two prior case-control studies in New York, we demonstrated that blood harmane concentration was elevated in ET patients vs. controls, and especially in familial ET cases. These findings, however, have been derived from a study of cases ascertained through a single tertiary referral center in New York. Our objective was to determine whether blood harmane concentrations are elevated in familial and sporadic ET cases, ascertained from central Spain, compared to controls without ET. Blood harmane concentrations were quantified by a well-established high performance liquid chromatography method. The median harmane concentrations were: 2.09 g(-10)/ml (138 controls), 2.41 g(-10)/ml (68 sporadic ET), and 2.90 g(-10)/ml (62 familial ET). In an unadjusted logistic regression analysis, log blood harmane concentration was not significantly associated with diagnosis (familial ET vs. control): odds ratio=1.56, p=0.26. In a logistic regression analysis that adjusted for evaluation start time, which was an important confounding variable, the odds ratio increased to 2.35, p=0.049. Blood harmane levels were slightly elevated in a group of familial ET cases compared to a group of controls in Spain. These data seem to further extend our observations from New York to a second cohort of ET cases in Spain. This neurotoxin continues to be a source of interest for future confirmatory research. Copyright © 2012 Elsevier Inc. All rights reserved.

BLOOD HARMANE (1-METHYL-9H-PYRIDO[3,4-B]INDOLE) CONCENTRATION IN ESSENTIAL TREMOR CASES IN SPAIN

PubMed Central

Louis, Elan D.; Benito-León, Julian; Moreno-García, Sara; Vega, Saturio; Romero, Juan Pablo; Bermejo-Pareja, Felix; Gerbin, Marina; Viner, Amanda S.; Factor-Litvak, Pam; Jiang, Wendy; Zheng, Wei

2012-01-01

Background Environmental correlates for essential tremor (ET) are largely unexplored. The search for such environmental factors has involved the study of a number of neurotoxins. Harmane (1-methyl-9H-pyrido[3,4-b]indole) is a potent tremor-producing toxin. In two prior case-control studies in New York, we demonstrated that blood harmane concentration was elevated in ET patients vs. controls, and especially in familial ET cases. These findings, however, have been derived from a study of cases ascertained through a single tertiary referral center in New York. Objective Our objective was to determine whether blood harmane concentrations are elevated in familial and sporadic ET cases, ascertained from central Spain, compared to controls without ET. Methods Blood harmane concentrations were quantified by a well-established high performance liquid chromatography method. Results The median harmane concentrations were: 2.09 g−10/ml (138 controls), 2.41 g−10/ml (68 sporadic ET), and 2.90 g−10/ml (62 familial ET). In an unadjusted logistic regression analysis, log blood harmane concentration was not significantly associated with diagnosis (familial ET vs. control): odds ratio = 1.56, p = 0.26. In a logistic regression analysis that adjusted for evaluation start time, which was an important confounding variable, the odds ratio increased to 2.35, p = 0.049. Conclusions Blood harmane levels were slightly elevated in a group of familial ET cases compared to a group of controls in Spain. These data seem to further extend our observations from New York to a second cohort of ET cases in Spain. This neurotoxin continues to be a source of interest for future confirmatory research. PMID:22981972

Experiment-Based Teaching in Advanced Control Engineering

ERIC Educational Resources Information Center

Precup, R.-E.; Preitl, S.; Radac, M.-B.; Petriu, E. M.; Dragos, C.-A.; Tar, J. K.

2011-01-01

This paper discusses an experiment-based approach to teaching an advanced control engineering syllabus involving controlled plant analysis and modeling, control structures and algorithms, real-time laboratory experiments, and their assessment. These experiments are structured around the representative case of the longitudinal slip control of an…

The Effect of Using Case Studies in Business Statistics

ERIC Educational Resources Information Center

Pariseau, Susan E.; Kezim, Boualem

2007-01-01

The authors evaluated the effect on learning of using case studies in business statistics courses. The authors divided students into 3 groups: a control group, a group that completed 1 case study, and a group that completed 3 case studies. Results evidenced that, on average, students whom the authors required to complete a case analysis received…

The cost of absenteeism and short-term disability associated with colorectal cancer: a case-control study.

PubMed

Yaldo, Avin; Seal, Brian S; Lage, Maureen J

2014-08-01

Examine the incremental impact of absenteeism and short-term disability associated with colorectal cancer (CRC). Absenteeism and short-term disability data were used for a case-control analysis of a healthy cohort (controls) compared with CRC patients (cases). Cases were matched to controls on the basis of age, sex, and region of residence. Multivariate regression models examined the costs of absenteeism and short-term disability, controlling for patient characteristics, prior medical costs, and patient general health. Compared with controls, CRC patients experience significantly higher short-term disability costs (mean, $45,716 vs $7367 [P < 0.0001]; median, $35,827 vs $7365 [P < 0.0001]), as well as significantly higher absenteeism costs (mean, $8841 vs $4596 [P < 0.0001]; median, $9971 vs $4795 [P < 0.0001]) in the 1 year after diagnosis of CRC. Colorectal cancer is associated with significant work-related productivity loss costs in the first year after diagnosis.

Analysis of copy number variation in Alzheimer's disease in a cohort of clinically characterized and neuropathologically verified individuals.

PubMed

Swaminathan, Shanker; Huentelman, Matthew J; Corneveaux, Jason J; Myers, Amanda J; Faber, Kelley M; Foroud, Tatiana; Mayeux, Richard; Shen, Li; Kim, Sungeun; Turk, Mari; Hardy, John; Reiman, Eric M; Saykin, Andrew J

2012-01-01

Copy number variations (CNVs) are genomic regions that have added (duplications) or deleted (deletions) genetic material. They may overlap genes affecting their function and have been shown to be associated with disease. We previously investigated the role of CNVs in late-onset Alzheimer's disease (AD) and mild cognitive impairment using Alzheimer's Disease Neuroimaging Initiative (ADNI) and National Institute of Aging-Late Onset AD/National Cell Repository for AD (NIA-LOAD/NCRAD) Family Study participants, and identified a number of genes overlapped by CNV calls. To confirm the findings and identify other potential candidate regions, we analyzed array data from a unique cohort of 1617 Caucasian participants (1022 AD cases and 595 controls) who were clinically characterized and whose diagnosis was neuropathologically verified. All DNA samples were extracted from brain tissue. CNV calls were generated and subjected to quality control (QC). 728 cases and 438 controls who passed all QC measures were included in case/control association analyses including candidate gene and genome-wide approaches. Rates of deletions and duplications did not significantly differ between cases and controls. Case-control association identified a number of previously reported regions (CHRFAM7A, RELN and DOPEY2) as well as a new gene (HLA-DRA). Meta-analysis of CHRFAM7A indicated a significant association of the gene with AD and/or MCI risk (P = 0.006, odds ratio = 3.986 (95% confidence interval 1.490-10.667)). A novel APP gene duplication was observed in one case sample. Further investigation of the identified genes in independent and larger samples is warranted.

Hyperactivity of the default-mode network in first-episode, drug-naive schizophrenia at rest revealed by family-based case-control and traditional case-control designs.

PubMed

Guo, Wenbin; Liu, Feng; Chen, Jindong; Wu, Renrong; Li, Lehua; Zhang, Zhikun; Chen, Huafu; Zhao, Jingping

2017-03-01

Abnormal regional activity and functional connectivity of the default-mode network (DMN) have been reported in schizophrenia. However, previous studies may have been biased by unmatched case-control design. To limit such bias, the present study used both the family-based case-control design and the traditional case-control design to investigate abnormal regional activity of the DMN in patients with schizophrenia at rest.Twenty-eight first-episode, drug-naive patients with schizophrenia, 28 age-, sex-matched unaffected siblings of the patients (family-based controls, FBC), and 40 healthy controls (HC) underwent resting-state functional magnetic resonance imaging (fMRI) scans. The group-independent component analysis and fractional amplitude of low-frequency fluctuation (fALFF) methods were used to analyze the data.Patients with schizophrenia show increased fALFF in an overlapped region of the right superior medial prefrontal cortex (MPFC) relative to the FBC and the HC. Compared with the HC, the patients and the FBC exhibit increased fALFF in an overlapped region of the left posterior cingulate cortex/precuneus (PCC/PCu). Furthermore, the z values of the 2 overlapped regions can separate the patients from the FBC/HC, and separate the patients/FBC from the HC with relatively high sensitivity and specificity.Both the family-based case-control and traditional case-control designs reveal hyperactivity of the DMN in first-episode, drug-naive patients with paranoid schizophrenia, which highlights the importance of the DMN in the neurobiology of schizophrenia. Family-based case-control design can limit the confounding effects of environmental factors in schizophrenia. Combination of the family-based case-control and traditional case-control designs may be a viable option for the neuroimaging studies.

A retrospective likelihood approach for efficient integration of multiple omics factors in case-control association studies.

PubMed

Balliu, Brunilda; Tsonaka, Roula; Boehringer, Stefan; Houwing-Duistermaat, Jeanine

2015-03-01

Integrative omics, the joint analysis of outcome and multiple types of omics data, such as genomics, epigenomics, and transcriptomics data, constitute a promising approach for powerful and biologically relevant association studies. These studies often employ a case-control design, and often include nonomics covariates, such as age and gender, that may modify the underlying omics risk factors. An open question is how to best integrate multiple omics and nonomics information to maximize statistical power in case-control studies that ascertain individuals based on the phenotype. Recent work on integrative omics have used prospective approaches, modeling case-control status conditional on omics, and nonomics risk factors. Compared to univariate approaches, jointly analyzing multiple risk factors with a prospective approach increases power in nonascertained cohorts. However, these prospective approaches often lose power in case-control studies. In this article, we propose a novel statistical method for integrating multiple omics and nonomics factors in case-control association studies. Our method is based on a retrospective likelihood function that models the joint distribution of omics and nonomics factors conditional on case-control status. The new method provides accurate control of Type I error rate and has increased efficiency over prospective approaches in both simulated and real data. © 2015 Wiley Periodicals, Inc.

Computer-Aided System Engineering and Analysis (CASE/A) Programmer's Manual, Version 5.0

NASA Technical Reports Server (NTRS)

Knox, J. C.

1996-01-01

The Computer Aided System Engineering and Analysis (CASE/A) Version 5.0 Programmer's Manual provides the programmer and user with information regarding the internal structure of the CASE/A 5.0 software system. CASE/A 5.0 is a trade study tool that provides modeling/simulation capabilities for analyzing environmental control and life support systems and active thermal control systems. CASE/A has been successfully used in studies such as the evaluation of carbon dioxide removal in the space station. CASE/A modeling provides a graphical and command-driven interface for the user. This interface allows the user to construct a model by placing equipment components in a graphical layout of the system hardware, then connect the components via flow streams and define their operating parameters. Once the equipment is placed, the simulation time and other control parameters can be set to run the simulation based on the model constructed. After completion of the simulation, graphical plots or text files can be obtained for evaluation of the simulation results over time. Additionally, users have the capability to control the simulation and extract information at various times in the simulation (e.g., control equipment operating parameters over the simulation time or extract plot data) by using "User Operations (OPS) Code." This OPS code is written in FORTRAN with a canned set of utility subroutines for performing common tasks. CASE/A version 5.0 software runs under the VAX VMS(Trademark) environment. It utilizes the Tektronics 4014(Trademark) graphics display system and the VTIOO(Trademark) text manipulation/display system.

Mycoplasma and ureaplasma infection and male infertility: a systematic review and meta-analysis.

PubMed

Huang, C; Zhu, H L; Xu, K R; Wang, S Y; Fan, L Q; Zhu, W B

2015-09-01

The relationship between mycoplasma and ureaplasma infection and male infertility has been studied widely; however, results remain controversial. This meta-analysis investigated the association between genital ureaplasmas (Ureaplasma urealyticum, Ureaplasma parvum) and mycoplasmas (Mycoplasma hominis, Mycoplasma genitalium), and risk of male infertility. Differences in prevalence of ureaplasma and mycoplasma infection between China and the rest of the world were also compared. Study data were collected from PubMed, Embase and the China National Knowledge Infrastructure. Summary odds ratio (OR) with 95% confidence interval (CI) was applied to assess the relationship. Heterogeneity testing and publication bias testing were also performed. A total of 14 studies were used: five case-control studies with 611 infertile cases and 506 controls featuring U. urealyticum infection, and nine case-control studies with 2410 cases and 1223 controls concerning M. hominis infection. Two other infection (U. parvum and M. genitalium) were featured in five and three studies, respectively. The meta-analysis results indicated that U. parvum and M. genitalium are not associated with male infertility. However, a significant relationship existed between U. urealyticum and M. hominis and male infertility. Comparing the global average with China, a significantly higher positive rate of U. urealyticum, but a significantly lower positive rate of M. hominis, was observed in both the infertile and control groups in China. © 2015 American Society of Andrology and European Academy of Andrology.

Approximate analysis for repeated eigenvalue problems with applications to controls-structure integrated design

NASA Technical Reports Server (NTRS)

Kenny, Sean P.; Hou, Gene J. W.

1994-01-01

A method for eigenvalue and eigenvector approximate analysis for the case of repeated eigenvalues with distinct first derivatives is presented. The approximate analysis method developed involves a reparameterization of the multivariable structural eigenvalue problem in terms of a single positive-valued parameter. The resulting equations yield first-order approximations to changes in the eigenvalues and the eigenvectors associated with the repeated eigenvalue problem. This work also presents a numerical technique that facilitates the definition of an eigenvector derivative for the case of repeated eigenvalues with repeated eigenvalue derivatives (of all orders). Examples are given which demonstrate the application of such equations for sensitivity and approximate analysis. Emphasis is placed on the application of sensitivity analysis to large-scale structural and controls-structures optimization problems.

Evaluation of salivary tumor necrosis factor-alpha in patients with the chronic periodontitis: A case-control study.

PubMed

Yousefimanesh, Hojatollah; Maryam, Robati; Mahmoud, Jahangirnezhad; Mehri, Ghafourian Boroujerdnia; Mohsen, Taghipour

2013-11-01

Periodontitis is a chronic infectious disease that leads to inflammation of the tissues supporting the teeth, bone loss, attachment loss progressively. In chronic periodontitis for starting the host response and inflammatory reaction, the presence of the infectious agent is necessary. One of inflammatory factors is tumor necrosis factor-alpha (TNF-α) that appear to be important in the destruction of periodontal tissues that were examined in this study. This study was performed in the laboratory and case-control study. The samples of study collected from 30 individuals with chronic periodontitis and 30 healthy controls that matched for age and sex, together. Unstimulated saliva samples were collected from patients and then TNF-α level were measured by enzyme-linked immunosorbent assay and were compared with the control group. In this study for statistical analysis, Mann-Whitney was used. There were differences in mean salivary concentrations of TNF-α in controls and patients. The average concentration in the case group was 9.1 (pg/ml) and the control group was 8.7 (pg/ml), but there was no significant difference between case and control groups (P > 0.05). The results of this analysis showed no significant relationship between two groups TNF-α concentration. This biomarker can not seem to be a good index to evaluate or predict periodontal disease.

Cost accounting, management control, and planning in health care.

PubMed

Siegrist, R B; Blish, C S

1988-02-01

Advantages and pharmacy applications of computerized hospital management-control and planning systems are described. Hospitals must define their product lines; patient cases, not tests or procedures, are the end product. Management involves operational control, management control, and strategic planning. Operational control deals with day-to-day management on the task level. Management control involves ensuring that managers use resources effectively and efficiently to accomplish the organization's objectives. Management control includes both control of unit costs of intermediate products, which are procedures and services used to treat patients and are managed by hospital department heads, and control of intermediate product use per case (managed by the clinician). Information from the operation and management levels feeds into the strategic plan; conversely, the management level controls the plan and the operational level carries it out. In the system developed at New England Medical Center, Boston, Massachusetts, the intermediate product-management system enables managers to identify intermediate products, develop standard costs, simulate changes in departmental costs, and perform variance analysis. The end-product management system creates a patient-level data-base, identifies end products (patient-care groupings), develops standard resource protocols, models alternative assumptions, performs variance analysis, and provides concurrent reporting. Examples are given of pharmacy managers' use of such systems to answer questions in the areas of product costing, product pricing, variance analysis, productivity monitoring, flexible budgeting, modeling and planning, and comparative analysis.(ABSTRACT TRUNCATED AT 250 WORDS)

Can overt diabetes mellitus be predicted by an early A1C value in gestational diabetics?

PubMed

Granada, Catalina; Forbes, Joanna; Sangi-Haghpeykar, Haleh; Davidson, Christina

2014-01-01

To test the hypothesis that a hemoglobin A1C value (A1C) in early pregnancy is predictive of overt diabetes mellitus (DM) postpartum in women with gestational diabetes (GDM). In this case-control analysis of women with an early pregnancy diagnosis of GDM, we estimated the association between an early pregnancy A1C and subsequent diagnosis of DM. Women with a normal postpartum diabetic screen (controls) were compared against those with confirmed postpartum DM (cases). Ability of A1C levels to predict DM was examined via logistic regression analysis and corresponding receiver operating characteristic values. During the 10-year study period 166 women met the inclusion criteria: 140 (84%) had normal postpartum testing (controls), and 26 (16%) were diagnosed with DM (cases). The mean A1C value was significantly higher among cases than controls (6.7 vs. 5.6, p < 0.0001, SD 1.3-5). Cases had A1Cs ranging from 5.5- 11.7%, while controls had A1Cs ranging from 4.3-7.8%. The best discriminatory cut point for postpartum DM was an A1C > 5.9% (sensitivity 81%, specificity 83%, positive predictive value 47%, negative predictive value Our findings suggest that an elevated early pregnancy A1C may be predictive of overt DM. Larger studies are needed to further validate this association.

Vitamin E Intake and Risk of Renal Cell Carcinoma: A Meta-Analysis of 7 Case-Control Studies.

PubMed

Shang, Yonggang; Yi, Shanhong; Cui, Dong; Han, Guangwei; Liu, Chengcheng

2015-07-01

Vitamin E intake may reduce the risk of renal cell carcinoma, but the results were inconsistent. Hence, we conducted a meta-analysis to assess the association between dietary vitamin E intake and the risk of renal cell carcinoma. We searched PubMed to identify the relevant case-control studies up to June 2014. Reference lists of retrieved articles were also reviewed. Odds ratios and corresponding 95% confidence intervals were used to estimate the association between dietary vitamin E intake and the risk of renal cell carcinoma. We identified 7 case-control studies regarding dietary vitamin E intake and risk of renal cell carcinoma, involving 5789 cases and 14866 controls. The odds ratio of renal cell carcinoma for the highest compared with the lowest dietary vitamin E intake was 0.75 (95% confidence interval: 0.59-0.91), and heterogeneity was observed across studies. The association between dietary vitamin E intake and the risk of renal cell carcinoma was not significantly differed by gender, but this association were inconsistent in the North American and European populations. Our study provided a evidence that there was a significant inverse association of dietary vitamin E intake with risk of renal cell carcinoma. However, this finding was based on the case-control studies, more well-designed cohort studies are needed. Copyright © 2015 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

The association of contact lens solution use and Acanthamoeba keratitis

PubMed Central

Joslin, Charlotte E.; Tu, Elmer Y.; Shoff, Megan E.; Booton, Gregory C.; Fuerst, Paul A.; McMahon, Timothy T.; Anderson, Robert J.; Dworkin, Mark S.; Sugar, Joel; Davis, Faith G.; Stayner, Leslie T.

2009-01-01

Purpose Diagnosis of Acanthamoeba keratitis, a rare but serious corneal infection, has recently increased significantly at the University of Illinois at Chicago (UIC) Cornea Service. The purpose is to investigate Acanthamoeba keratitis risk factors. Design Retrospective case-control study. Methods Setting University, tertiary care hospital. Patients Fifty-five Acanthamoeba keratitis cases with contact lens use were diagnosed between May 1, 2003 and September 15, 2006. Clinic-matched controls with contact lens use were recruited. Subjects completed surveys targeting lens hygiene, contact lens solution use, and water exposure. Main Outcome Measure Acanthamoeba keratitis. Results Thirty-nine (73.6%) cases and 113 (65.3%) controls participated; 38 cases had complete contact lens data. Thirty-five of 38 cases (92.1%) and 47 of 100 controls (47.0%) used soft lenses. Analysis was performed on 30 cases and 39 controls with matched pairs with soft lens use. Exclusive use of AMO Complete MoisturePlus Multi-Purpose Solution was independently associated with Acanthamoeba keratitis in multivariable analysis (55.2% vs. 10.5%; OR, 16.67; 95% CI, 2.11–162.63; p = 0.008). However, 38.8% of cases reported no use of AMO Complete MoisturePlus Multi-Purpose Solution or used it in combination with other solutions. Although not statistically significant, additional hygiene-related variables (solution ‘reuse’, lack of ‘rubbing’, and showering with lenses) suggest a pattern of risk,. Conclusions AMO Complete MoisturePlus Multi-Purpose Solution use is independently associated with Acanthamoeba keratitis among soft contact lens users. However, it does not explain all cases, suggesting additional factors. Further research into environmental risk factors and hygiene practices is warranted, especially considering this is the second outbreak of an atypical, contact lens-related infection. PMID:17588524

The association of contact lens solution use and Acanthamoeba keratitis.

PubMed

Joslin, Charlotte E; Tu, Elmer Y; Shoff, Megan E; Booton, Gregory C; Fuerst, Paul A; McMahon, Timothy T; Anderson, Robert J; Dworkin, Mark S; Sugar, Joel; Davis, Faith G; Stayner, Leslie T

2007-08-01

To investigate Acanthamoeba keratitis (AK) risk factors. Diagnosis of AK, a rare but serious corneal infection, has recently increased significantly at the University of Illinois at Chicago (UIC) Cornea Service. Retrospective case-control study. settings: University, tertiary care hospital. patients: Fifty-five AK cases with contact lens use were diagnosed between May 1, 2003 and September 15, 2006. Clinic-matched controls with contact lens use were recruited. Subjects completed surveys targeting lens hygiene, contact lens solution use, and water exposure. main outcome measure: Acanthamoeba keratitis. Thirty-nine (73.6%) cases and 113 (65.3%) controls participated; 38 cases had complete contact lens data. Thirty-five of 38 cases (92.1%) and 47 of 100 controls (47.0%) used soft lenses. Analysis was performed on 30 cases and 39 controls with matched pairs with soft lens use. Exclusive use of Advance Medical Optics (AMO) Complete MoisturePlus Multi-Purpose Solution was independently associated with AK in multivariable analysis (55.2% vs 10.5%; odds ratio [OR], 16.67; 95% confidence interval [CI] 2.11 to 162.63; P = .008). However, 38.8% of cases reported no use of AMO Complete MoisturePlus Multi-Purpose Solution either alone or in combination with other solutions. Although not statistically significant, additional hygiene-related variables (solution "reuse," lack of "rubbing," and showering with lenses) suggest a pattern of risk. AMO Complete MoisturePlus Multi-Purpose Solution use is independently associated with AK among soft contact lens users. However, it does not explain all cases, suggesting additional factors. Further research into environmental risk factors and hygiene practices is warranted, especially considering this is the second outbreak of an atypical, contact lens-related infection.

Molecular genetic studies in Saudi population; identified variants from GWAS and meta-analysis in stroke.

PubMed

Alharbi, Khalid Khalaf; Ali Khan, Imran; Alotaibi, Mohammad Abdullah; Saud Aloyaid, Abdullah; Al-Basheer, Haifa Abdulaziz; Alghamdi, Naelah Abdullah; Al-Baradie, Raid Saleem; Al-Sulaiman, A M

2018-01-01

Stroke is a multifactorial and heterogeneous disorder, correlates with heritability and considered as one of the major diseases. The prior reports performed the variable models such as genome-wide association studies (GWAS), replication, case-control, cross-sectional and meta-analysis studies and still, we lack diagnostic marker in the global world. There are limited studies were carried out in Saudi population, and we aim to investigate the molecular association of single nucleotide polymorphisms (SNPs) identified through GWAS and meta-analysis studies in stroke patients in the Saudi population. In this case-control study, we have opted gender equality of 207 cases and 207 controls from the capital city of Saudi Arabia in King Saud University Hospital. The peripheral blood (5 ml) sample will be collected in two different vacutainers, and three mL of the coagulated blood will be used for lipid analysis (biochemical tests) and two mL will be used for DNA analysis (molecular tests). Genomic DNA will be extracted with the collected blood samples, and specific primers will be designed for the opted SNPs ( SORT1 -rs646218 and OLR1 -rs11053646 polymorphisms) and PCR-RFLP will be performed and randomly DNA sequencing will be carried out to cross check the results. The rs646218 and rs11053646 polymorphisms were significantly associated with allele, genotype and dominant models with and without crude odds ratios (OR's) and Multiple logistic regression analysis (p < 0.05). Correlation between lipid profile and genotypes has confirmed the significant relation between triglycerides and rs646218 and rs1105364 6polymorphisms. However, rs11053646 polymorphism was correlated with HDLC (p = 0.04). Genotypes were examined in both males' vs. males and females' vs. females in cases and control and we concluded that in rs11053646 polymorphisms with male subjects compared between cases and controls found to be associated with dominant model heterozygote genotypes (p < 0.05). The results of the current study confirmed the SORT1 and OLR1  SNPs were associated in the Saudi population. The current results were in the association with the prior study results documented through GWAS and meta-analysis association. However, other ethnic population studies should be performed to rule out in the human hereditary diseases.

Reduced Risk of Barrett's Esophagus in Statin Users: Case-Control Study and Meta-Analysis.

PubMed

Beales, Ian L P; Dearman, Leanne; Vardi, Inna; Loke, Yoon

2016-01-01

Use of statins has been associated with a reduced incidence of esophageal adenocarcinoma in population-based studies. However there are few studies examining statin use and the development of Barrett's esophagus. The purpose of this study was to examine the association between statin use and the presence of Barrett's esophagus in patients having their first gastroscopy. We have performed a case-control study comparing statin use between patients with, and without, an incident diagnosis of non-dysplastic Barrett's esophagus. Male Barrett's cases (134) were compared to 268 male age-matched controls in each of two control groups (erosive gastro-esophageal reflux and dyspepsia without significant upper gastrointestinal disease). Risk factor and drug exposure were established using standardised interviews. Logistic regression was used to compare statin exposure and correct for confounding factors. We performed a meta-analysis pooling our results with three other case-control studies. Regular statin use was associated with a significantly lower incidence of Barrett's esophagus compared to the combined control groups [adjusted OR 0.62 (95 % confidence intervals 0.37-0.93)]. This effect was more marked in combined statin plus aspirin users [adjusted OR 0.43 (95 % CI 0.21-0.89)]. The inverse association between statin or statin plus aspirin use and risk of Barrett's was significantly greater with longer duration of use. Meta-analysis of pooled data (1098 Barrett's, 2085 controls) showed that statin use was significantly associated with a reduced risk of Barrett's esophagus [pooled adjusted OR 0.63 (95 % CI 0.51-0.77)]. Statin use is associated with a reduced incidence of a new diagnosis of Barrett's esophagus.

3D marker-controlled watershed for kidney segmentation in clinical CT exams.

PubMed

Wieclawek, Wojciech

2018-02-27

Image segmentation is an essential and non trivial task in computer vision and medical image analysis. Computed tomography (CT) is one of the most accessible medical examination techniques to visualize the interior of a patient's body. Among different computer-aided diagnostic systems, the applications dedicated to kidney segmentation represent a relatively small group. In addition, literature solutions are verified on relatively small databases. The goal of this research is to develop a novel algorithm for fully automated kidney segmentation. This approach is designed for large database analysis including both physiological and pathological cases. This study presents a 3D marker-controlled watershed transform developed and employed for fully automated CT kidney segmentation. The original and the most complex step in the current proposition is an automatic generation of 3D marker images. The final kidney segmentation step is an analysis of the labelled image obtained from marker-controlled watershed transform. It consists of morphological operations and shape analysis. The implementation is conducted in a MATLAB environment, Version 2017a, using i.a. Image Processing Toolbox. 170 clinical CT abdominal studies have been subjected to the analysis. The dataset includes normal as well as various pathological cases (agenesis, renal cysts, tumors, renal cell carcinoma, kidney cirrhosis, partial or radical nephrectomy, hematoma and nephrolithiasis). Manual and semi-automated delineations have been used as a gold standard. Wieclawek Among 67 delineated medical cases, 62 cases are 'Very good', whereas only 5 are 'Good' according to Cohen's Kappa interpretation. The segmentation results show that mean values of Sensitivity, Specificity, Dice, Jaccard, Cohen's Kappa and Accuracy are 90.29, 99.96, 91.68, 85.04, 91.62 and 99.89% respectively. All 170 medical cases (with and without outlines) have been classified by three independent medical experts as 'Very good' in 143-148 cases, as 'Good' in 15-21 cases and as 'Moderate' in 6-8 cases. An automatic kidney segmentation approach for CT studies to compete with commonly known solutions was developed. The algorithm gives promising results, that were confirmed during validation procedure done on a relatively large database, including 170 CTs with both physiological and pathological cases.

The role of brain-derived neurotrophic factor (BDNF) Val66Met genetic polymorphism in bipolar disorder: a case-control study, comorbidities, and meta-analysis of 16,786 subjects.

PubMed

González-Castro, Thelma Beatriz; Nicolini, Humberto; Lanzagorta, Nuria; López-Narváez, Lilia; Genis, Alma; Pool García, Sherezada; Tovilla-Zárate, Carlos Alfonso

2015-02-01

The aim of this study was to evaluate the association of Val66Met brain-derived neurotrophic factor (BDNF) polymorphism with bipolar disorder in (i) a meta-analysis and (ii) a case-control study in a Mexican population. We also investigated the possible association of this polymorphism with clinical features. We performed a keyword search of the PubMed and Web of Science databases. A total of 22 studies that have investigated the association of Val66Met (rs6265) with bipolar disorder were selected for inclusion and combined with random effects meta-analysis, using allelic, additive, dominant, and recessive models. Finally, the single nucleotide polymorphism (rs6265) Val66Met in the BDNF gene was genotyped and compared between 139 patients with bipolar disorder and 141 healthy volunteers in a Mexican population. The pooled results from the meta-analysis (9,349 cases and 7,437 controls) did not show a significant association in any of the models. The same results were obtained in our case-control study when analyzing the distribution of the genotypic frequencies of the Val66Met polymorphism in patients with bipolar disorder. However, when we analyzed the association between rs6265 and lifetime history of suicidal behavior, we found an association between genotype Val-Val and suicide attempt (p = 0.02). Although the present study has some limitations, the results indicate a lack of association between the Val66Met polymorphism and bipolar disorder. However, in our case-control study in a Mexican population, the Val66Met polymorphism was associated with suicidal behavior in patients with bipolar disorder. Nevertheless, it is important to consider potential interactions of the BDNF gene, the environment, and different inheritance patterns, when carrying out future genetic studies with larger samples. © 2014 The Authors. Bipolar Disorders Published by John Wiley & Sons Ltd.

CONDUIT: A New Multidisciplinary Integration Environment for Flight Control Development

NASA Technical Reports Server (NTRS)

Tischler, Mark B.; Colbourne, Jason D.; Morel, Mark R.; Biezad, Daniel J.; Levine, William S.; Moldoveanu, Veronica

1997-01-01

A state-of-the-art computational facility for aircraft flight control design, evaluation, and integration called CONDUIT (Control Designer's Unified Interface) has been developed. This paper describes the CONDUIT tool and case study applications to complex rotary- and fixed-wing fly-by-wire flight control problems. Control system analysis and design optimization methods are presented, including definition of design specifications and system models within CONDUIT, and the multi-objective function optimization (CONSOL-OPTCAD) used to tune the selected design parameters. Design examples are based on flight test programs for which extensive data are available for validation. CONDUIT is used to analyze baseline control laws against pertinent military handling qualities and control system specifications. In both case studies, CONDUIT successfully exploits trade-offs between forward loop and feedback dynamics to significantly improve the expected handling, qualities and minimize the required actuator authority. The CONDUIT system provides a new environment for integrated control system analysis and design, and has potential for significantly reducing the time and cost of control system flight test optimization.

Applied Behavior Analysis and Statistical Process Control?

ERIC Educational Resources Information Center

Hopkins, B. L.

1995-01-01

Incorporating statistical process control (SPC) methods into applied behavior analysis is discussed. It is claimed that SPC methods would likely reduce applied behavior analysts' intimate contacts with problems and would likely yield poor treatment and research decisions. Cases and data presented by Pfadt and Wheeler (1995) are cited as examples.…

Excess Readmission vs Excess Penalties: Maximum Readmission Penalties as a Function of Socioeconomics and Geography.

PubMed

Caracciolo, Chris; Parker, Devin; Marshall, Emily; Brown, Jeremiah

2017-08-01

The Hospital Readmission Reduction Program (HRRP) penalizes hospitals with "excess" readmissions up to 3% of Medicare reimbursement. Approximately 75% of eligible hospitals received penalties, worth an estimated $428 million, in fiscal year 2015. To identify demographic and socioeconomic disparities between matched and localized maximum-penalty and no-penalty hospitals. A case-control study in which cases included were hospitals to receive the maximum 3% penalty under the HRRP during the 2015 fiscal year. Controls were drawn from no-penalty hospitals and matched to cases by hospital characteristics (primary analysis) or geographic proximity (secondary analysis). A selectiion of 3383 US hospitals eligible for HRRP. Thirty-nine case and 39 control hospitals from the HRRP cohort. Socioeconomic status variables were collected by the American Community Survey. Hospital and health system characteristics were drawn from Centers for Medicare and Medicaid Services, American Hospital Association, and Dartmouth Atlas of Health Care. The statistical analysis was conducted using Student t tests. Thirty-nine hospitals received a maximum penalty. Relative to controls, maximum-penalty hospitals in counties with lower SES profiles are defined by increased poverty rates (19.1% vs 15.5%, = 0.015) and lower rates of high school graduation (82.2% vs 87.5%, = 0.001). County level age, sex, and ethnicity distributions were similar between cohorts. Cases were more likely than controls to be in counties with low socioeconomic status; highlighting potential unintended consequences of national benchmarks for phenomena underpinned by environmental factors; specifically, whether maximum penalties under the HRRP are a consequence of underperforming hospitals or a manifestation of underserved communities. © 2017 Society of Hospital Medicine

Association between periodontitis and ischemic stroke: a systematic review and meta-analysis.

PubMed

Leira, Yago; Seoane, Juan; Blanco, Miguel; Rodríguez-Yáñez, Manuel; Takkouche, Bahi; Blanco, Juan; Castillo, José

2017-01-01

Several observational studies have suggested an association between periodontitis and cerebral ischemia. This meta-analysis aimed to investigate whether this link exists, and if so, the degree to which it is significant. The Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guideline for systematic review was used. The search strategy included using electronic databases and hand searching works published up to March 2015. MEDLINE via PubMed, EMBASE, Proceedings Web of Science and Current Contents Connect were searched by two independent reviewers. Case-control, cross-sectional or cohort studies including patients with measures of periodontitis and ischemic stroke were eligible to be included in the analysis. Quality assessments of selected studies were performed. From a total of 414 titles and abstracts, 57 potentially relevant full text papers were identified. After inclusion criteria were applied, 8 studies were included in the present systematic review (5 case-control and 3 cohort studies). Although it was not the intention, cross-sectional studies were excluded due to eligibility criteria were not accomplished. Therefore, meta-analyses were conducted with data retrieved from the 8 studies included. These meta-analyses showed statistically significant association between periodontitis and ischemic stroke in both cohort pooled relative risks at 2.52 (1.77-3.58), and case-control studies pooled relative risks at 3.04 (1.10-8.43). In conclusion, the present meta-analysis demonstrated an association between periodontitis and ischemic stroke. However, well-designed prospective studies should be carried out to provide robust evidence of the link between both diseases. In regards to ischemic stroke subtypes, further case-control studies should be carried out to investigate whether there is any association between the different subtypes of cerebral infarcts and periodontitis.

Association between long travel and venous thromboembolic disease: a systematic review and meta-analysis of case-control studies

PubMed Central

Jiménez-Puente, Alberto; Perea-Milla, Emilio

2007-01-01

The term “economy-class syndrome” defines an infrequent episode of venous thromboembolism (VTED) related to a long travel, namely by plane. However, this relation has not clearly been demonstrated by investigators. We carried out a systematic review and a meta-analysis of cases-control studies that had studied this topic. We realised a systematic review of the literature and selected all the case-control studies published. Two authors carried out a methodological evaluation according to the Scottish Intercollegiate Guidelines Network items (concordance was analysed by weighted kappa index), and a systematic analysis of the potential biases of each study was assessed. We carried out the meta-analysis with the data extracted from the studies. We recovered eight cases-control studies. The relation between the antecedent of a long travel and subsequent VTED varied from OR = 1.1 to OR = 4.0 and was found to be significant in four studies. The studies were highly heterogeneous in methodology and so the results obtained about the relation between the long travel and the VTED and the score at SIGN50. Two meta-analysis were carried out: only with travels by plane in which the relation was not significant (OR = 1.21; CI 95%, 0.95–1.55) and with all types of transport, with a slightly significant relation (OR = 1.46; CI95%, 1.24–1.72). We may deduce from this systematic review that there does exist a weak association between episodes of VTED and a long travel, but not by plane specifically. The heterogeneity and the methodological quality of the studies published preclude of more robust conclusions. PMID:17899081

Mobile phone use and risk for intracranial tumors and salivary gland tumors - A meta-analysis.

PubMed

Bortkiewicz, Alicja; Gadzicka, Elżbieta; Szymczak, Wiesław

2017-02-21

Results of epidemiological studies on the association between use of mobile phone and brain cancer are ambiguous, as well as the results of 5 meta-analysis studies published to date. Since the last meta-analysis (2009), new case-control studies have been published, which theoretically could affect the conclusions on this relationship. Therefore, we decided to perform a new meta-analysis. We conducted a systematic review of multiple electronic data bases for relevant publications. The inclusion criteria were: original papers, case-control studies, published till the end of March 2014, measures of association (point estimates as odds ratio and confidence interval of the effect measured), data on individual exposure. Twenty four studies (26 846 cases, 50 013 controls) were included into the meta-analysis. A significantly higher risk of an intracranial tumor (all types) was noted for the period of mobile phone use over 10 years (odds ratio (OR) = 1.324, 95% confidence interval (CI): 1.028-1.704), and for the ipsilateral location (OR = 1.249, 95% CI: 1.022-1.526). The results support the hypothesis that long-term use of mobile phone increases risk of intracranial tumors, especially in the case of ipsilateral exposure. Further studies are needed to confirm this relationship. Int J Occup Med Environ Health 2017;30(1)27-43. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

Epidemiologic study of residential proximity to transmission lines and childhood cancer in California: description of design, epidemiologic methods and study population

PubMed Central

Kheifets, Leeka; Crespi, Catherine M; Hooper, Chris; Oksuzyan, Sona; Cockburn, Myles; Ly, Thomas; Mezei, Gabor

2015-01-01

We conducted a large epidemiologic case-control study in California to examine the association between childhood cancer risk and distance from the home address at birth to the nearest high-voltage overhead transmission line as a replication of the study of Draper et al. in the United Kingdom. We present a detailed description of the study design, methods of case ascertainment, control selection, exposure assessment and data analysis plan. A total of 5788 childhood leukemia cases and 3308 childhood central nervous system cancer cases (included for comparison) and matched controls were available for analysis. Birth and diagnosis addresses of cases and birth addresses of controls were geocoded. Distance from the home to nearby overhead transmission lines was ascertained on the basis of the electric power companies’ geographic information system (GIS) databases, additional Google Earth aerial evaluation and site visits to selected residences. We evaluated distances to power lines up to 2000 m and included consideration of lower voltages (60–69 kV). Distance measures based on GIS and Google Earth evaluation showed close agreement (Pearson correlation >0.99). Our three-tiered approach to exposure assessment allowed us to achieve high specificity, which is crucial for studies of rare diseases with low exposure prevalence. PMID:24045429

Genetic variants of MAOB affect serotonin level and specific behavioral attributes to increase autism spectrum disorder (ASD) susceptibility in males.

PubMed

Chakraborti, Barnali; Verma, Deepak; Karmakar, Arijit; Jaiswal, Preeti; Sanyal, Aritrika; Paul, Debarshi; Sinha, Swagata; Singh, Asem Surindro; Guhathakurta, Subhrangshu; Roychowdhury, Anirban; Panda, Chinmoy Kumar; Ghosh, Saurabh; Mohanakumar, Kochupurackal P; Mukhophadhyay, Kanchan; Rajamma, Usha

2016-11-03

Serotonergic system participates in various developmental processes and modulation of behaviour. Autism Spectrum Disorder (ASD) is characterized by a range of behavioral symptoms scaling from mild to severe. Abnormal 5-HT synthesis and signalling, platelet hyperserotonemia and amelioration of repetitive behaviours by SSRI are some of the key findings, which reinforced the hypothesis that serotonergic genes might act as ASD susceptible genes. Therefore, genes encoding monoamine oxidases A/B (MAOA/MAOB) received special attention as these genes are located on the X-chromosome and the gene products are responsible for 5-HT degradation. In the present study, we conducted population-based association analysis of eight markers of MAOB with ASD in a study cohort of 203 cases and 236 controls form India and examined its effect on platelet 5-HT content and behaviour. Gender-specific changes were observed for the contrasting LD between pair of markers among cases and controls. Case-control analysis demonstrated over-distribution of major C allele of rs2283728 and rs2283727 in male and female ASD cases respectively. Haplotypic distribution and interaction among markers showed more robust effect in male cases. Interestingly, male ASD cases displayed higher platelet 5-HT content in comparison to the respective controls. Quantitative trait analysis revealed significant correlation of genetic variants and haplotypes of MAOB markers, rs1799836 and rs6324 with increased platelet 5-HT level and CARS scores for specific behavioral symptoms respectively in males. This study suggests that MAOB increases ASD risk in males, possibly through its sex-specific regulatory effect on 5-HT metabolism and behavior. Copyright © 2016 Elsevier Inc. All rights reserved.

Associations between the rs6010620 polymorphism in RTEL1 and risk of glioma: a meta-analysis of 20,711 participants.

PubMed

Wu, Yao; Tong, Xiang; Tang, Ling-Li; Zhou, Kai; Zhong, Chuan-Hong; Jiang, Shu

2014-01-01

Associations between the rs6010620 polymorphism in the regulator of telomere elongation helicase1 (RTEL1) gene and glioma have been widely reported but the results were not inconclusive. The aim of the current study was to investigate the association between the rs6010620 polymorphism in RTEL1 gene and risk of glioma by meta-analysis. We searched PubMed, Embase, Wanfang Weipu and CNKI (China National Knowledge Infrastructure) databases, which included all research published 05 May 2014. A total of 8,292 cases and 12,419 controls from 14 case-control studies involving the rs6010620 polymorphism in the RTEL1 gene were included. Statistical analysis was performed using STATA 12.0 software. The results indicated that the rs6010620 polymorphism in RTEL1 gene was indeed associated with risk of glioma (OR=1.474, 95%CI=1.282-1.694, p<0.001). On subgroup analysis by ethnicity, we found associations between the rs6010620 polymorphism in the RTEL1 gene and risk of glioma in both Caucasians and Asians. The current meta-analysis suggested that the rs6010620 polymorphism in the RTEL1 gene might increase risk of glioma. In future, larger case-control studies are needed to confirm our results.

Case-control studies in diabetes. Do they really use a case-control design?

PubMed

Ramos, Analía; Mendoza, Lilian Cristina; Rabasa, Fernanda; Bolíbar, Ignasi; Puig, Teresa; Corcoy, Rosa

2017-07-01

Studies defined as case-control do not always use this design. We aimed to estimate the frequency of mislabelled case-control studies in published articles in the area of diabetes and to identify the predictors of incorrect labelling. We searched Medline and Web of Science for articles with "diabetes" and "case control" in title and filtered for language (English/Romance) and period (January 2010-December 2014). Inclusion criteria were: (1) statement to use a case-control design in title, (2) to be a final full-length publication and (3) to have original data in the area of diabetes. Three independent reviewers went through titles, looked for full texts and reviewed them. Discrepancies were settled with a fourth reviewer. Expert epidemiologist advice was requested in case of doubt. case-control mislabelling; addressed predictors: publication year, journal impact factor and journal subject. proportion of mislabelled CC articles and assessment of predictors by multivariate logistic regression analysis. We retrieved 362 articles, 251 of them fulfilling inclusion criteria. The proportion of mislabelled CC studies was 43.8% (confidence interval 95% 37.7-50.0%). Most mislabelled studies had a cross-sectional design (82.7%). Predictors of mislabelling were publication year, journal impact factor and journal area. A relevant subset of studies defined as case-control in the area of diabetes correspond to mislabelled cross-sectional studies. Incorrect labelling misleads readers regarding the interpretation of results and the cause-effect hypothesis. Researchers, reviewers and editors should be aware of and commit to settle this issue.

Robotic Single-Site and Conventional Laparoscopic Surgery in Gynecology: Clinical Outcomes and Cost Analysis of a Matched Case-Control Study.

PubMed

El Hachem, Lena; Andikyan, Vaagn; Mathews, Shyama; Friedman, Kathryn; Poeran, Jashvant; Shieh, Kenneth; Geoghegan, Michael; Gretz, Herbert F

2016-01-01

To assess the clinical outcomes and costs associated with robotic single-site (RSS) surgery compared with those of conventional laparoscopy (CL) in gynecology. Retrospective case-control study (Canadian Task Force classification II-2). University-affiliated community hospital. Female patients undergoing RSS or CL gynecologic procedures. Comparison of consecutive RSS gynecologic procedures (cases) undertaken between October 2013 and March 2014 with matched CL procedures (controls) completed during the same time period by the same surgeon. Patient demographic data, operative data, and hospital financial data were abstracted from the electronic charts and financial systems. An incremental cost analysis based on the use of disposable equipment was performed. Total hospital charges were determined for matched RSS cases vs CL cases. RSS surgery was completed in 25 out of 33 attempts; 3 cases were aborted before docking, and 5 were converted to a multisite surgery. There were no intraoperative complications or conversions to laparotomy. The completed cases included 11 adnexal cases and 14 hysterectomies, 3 of which included pelvic lymph node dissection. Compared with the CL group, total operative times were higher in the RSS group; however, there were no significant between-group differences in estimated blood loss, length of hospital stay, or complication rates. Disposable equipment cost per case, direct costs, and total hospital charges were evaluated. RSS was associated with an increased disposable cost per case of $248 to $378, depending on the method used for vaginal cuff closure. The average total hospital charges for matched outpatient adnexal surgery were $15,450 for the CL controls and $18,585 for the RSS cases (p < .001), and the average total hospital charges for matched outpatient benign hysterectomy were $14,623 for the CL controls and $21,412 for the RSS cases (p < .001). Although RSS surgery and CL have comparable clinical outcomes in selected patients, RSS surgery remains associated with increased incremental disposable cost per case and total hospital charges. Careful case selection and judicious use of equipment are necessary to maximize cost-effectiveness in RSS gynecologic surgery. Copyright © 2016 AAGL. Published by Elsevier Inc. All rights reserved.

Steep discounting of delayed monetary and food rewards in obesity: a meta-analysis.

PubMed

Amlung, M; Petker, T; Jackson, J; Balodis, I; MacKillop, J

2016-08-01

An increasing number of studies have investigated delay discounting (DD) in relation to obesity, but with mixed findings. This meta-analysis synthesized the literature on the relationship between monetary and food DD and obesity, with three objectives: (1) to characterize the relationship between DD and obesity in both case-control comparisons and continuous designs; (2) to examine potential moderators, including case-control v. continuous design, money v. food rewards, sample sex distribution, and sample age (18 years); and (3) to evaluate publication bias. From 134 candidate articles, 39 independent investigations yielded 29 case-control and 30 continuous comparisons (total n = 10 278). Random-effects meta-analysis was conducted using Cohen's d as the effect size. Publication bias was evaluated using fail-safe N, Begg-Mazumdar and Egger tests, meta-regression of publication year and effect size, and imputation of missing studies. The primary analysis revealed a medium effect size across studies that was highly statistically significant (d = 0.43, p < 10-14). None of the moderators examined yielded statistically significant differences, although notably larger effect sizes were found for studies with case-control designs, food rewards and child/adolescent samples. Limited evidence of publication bias was present, although the Begg-Mazumdar test and meta-regression suggested a slightly diminishing effect size over time. Steep DD of food and money appears to be a robust feature of obesity that is relatively consistent across the DD assessment methodologies and study designs examined. These findings are discussed in the context of research on DD in drug addiction, the neural bases of DD in obesity, and potential clinical applications.

Association between rs3087243 and rs231775 polymorphism within the cytotoxic T-lymphocyte antigen 4 gene and Graves' disease: a case/control study combined with meta-analyses

PubMed Central

Dai, Yu; Zeng, Tianshu; Xiao, Fei; Chen, Lulu; Kong, Wen

2017-01-01

We conducted a case/control study to assess the impact of SNP rs3087243 and rs231775 within the CTLA4 gene, on the susceptibility to Graves' disease (GD) in a Chinese Han dataset (271 cases and 298 controls). The frequency of G allele for rs3087243 and rs231775 was observed to be significantly higher in subjects with GD than in control subjects (p = 0.005 and p = 0.000, respectively). After logistic regression analysis, a significant association was detected between SNP rs3087243 and GD in the additive and recessive models. Similarly, association for the SNP rs231775 could also be detected in the additive model, dominant model and recessive model. A meta-analysis, including 27 published datasets along with the current dataset, was performed to further confirm the association. Consistent with our case/control results, rs3087243 and rs231775 showed a significant association with GD in all genetic models. Of note, ethnic stratification revealed that these two SNPs were associated with susceptibility to GD in populations of both Asian and European descent. In conclusion, our data support that the rs3087243 and rs231775 polymorphisms within the CTLA4 gene confer genetic susceptibility to GD. PMID:29299173

[Lung cancer and smoking in Asturias, Spain. A case-control study].

PubMed

Caicoya, M; Mirón, J A

2003-01-01

Lung cancer in Asturias is 1.4-fold greater than the Spanish average, while the proportion of smokers is similar. The objective of this study was to examine the relationship between lung cancer and smoking in Asturias. We performed a hospital-based, incident case control study. The cases were newly diagnosed lung cancer patients and controls were patients from the surgical wards. Information was sought on smoking, occupational exposures, and demographic variables. The analysis was performed by means of odds ratios (OR). One hundred ninety-seven cases and 196 controls were included in the analysis. The adjusted OR of cigarette smoking was 5.77 (95% CI, 2.96-11.22). The risk increased with the number of cigarettes smoked per day (chi 2 = 56.3), the number of packs/year (chi 2 = 48.4), and the age at which smoking started (chi 2 = 76.5). The OR diminished with the number of years of cessation (chi 2 = 39.9). The relationship between smoking and lung cancer in Asturias is similar to that found in other studies carried out in other parts of the western world. The magnitude of the OR may explain the frequency of lung cancer in Asturias. Greater efforts should be devoted to controlling this problem.

The London Fibromyalgia Epidemiology Study: comparing the demographic and clinical characteristics in 100 random community cases of fibromyalgia versus controls.

PubMed

White, K P; Speechley, M; Harth, M; Ostbye, T

1999-07-01

To identify demographic and clinical features that distinguish fibromyalgia (FM) from other chronic widespread pain. We identified 100 confirmed FM cases, 76 widespread pain controls, and 135 general controls in a random community survey of 3395 noninstitutionalized adults living in London, Ontario. FM cases were distinguished from pain controls using the 1990 American College of Rheumatology (ACR) classification criteria for FM. The mean age of FM cases was 47.8 years (range 19 to 86), the same as for pain controls; 86% of FM cases were female versus 67.1% of pain controls (p < 0.01). FM cases were less educated than general controls (p = 0.03). Male and female FM cases were similar, except females were older and reported more major symptoms (both p = 0.02). FM cases reported more severe pain and fatigue, more symptoms, more major symptoms, and worse overall health than pain controls or general controls. The most commonly reported major symptoms among FM cases were musculoskeletal pain (77.3%), fatigue (77.3%), severe fatigue lasting 24 h after minimal activity (77.0%), nonrestorative sleep (65.7%), and insomnia (56.0%). Subjects with 11-14 tender points were more similar to those with 15-18 tender points than to those with 7-10 points in 11 of 14 clinical variables. On multivariate analysis, 4 symptoms distinguished FM cases from pain controls: pain severity (p = 0.004), severe fatigue lasting 24 h after minimal activity (p = 0.006), weakness (p = 0.008), and self-reported swelling of neck glands (p = 0.01). In the general population, adults who meet the ACR definition of FM appear to have distinct features compared to those with chronic widespread pain who do not meet criteria.

Herpesviruses in etiopathogenesis of aggressive periodontitis: A meta-analysis based on case-control studies.

PubMed

Li, Fei; Zhu, Ce; Deng, Feng-Ying; Wong, May Chun Mei; Lu, Hai-Xia; Feng, Xi-Ping

2017-01-01

Previous studies have found that herpesviruses are associated with aggressive periodontitis (AgP). However, these findings are controversial. This meta-analysis was aimed at clarifying the association between herpesviruses and AgP. We identified eligible case-control studies evaluating the association between herpesviruses and AgP from PubMed and Embase databases in October 2015. Original data were extracted and quality assessment was done. Overall odds ratios (ORs) and 95% confidence intervals (CIs) were estimated. Random-effects model was determined. The stability was evaluated by sensitivity analysis. Finally, Egger's funnel plot was used to investigate the publication bias. Twelve case-control studies involving 322 patients and 342 controls were included in the present meta-analysis. The included case-control studies were assessed as high quality. The quantitative synthesis results for Epstein-Barr virus (EBV) showed significance (10 studies: p = 0.0008, OR = 6.11, 95% CI = 2.13-17.51); nevertheless, evidence of publication bias for EBV was considerable (EBV: Egger's test, p<0.001). Human cytomegalovirus (HCMV) and Herpes simplex virus type 1 (HSV-1) had significant association with AgP (12 studies for HCMV: p = 0.009, OR = 3.63, 95% CI = 2.15-6.13; 4 studies for HSV-1: p<0.001, OR = 19.19, 95% CI = 4.16-79.06). Sensitivity analyses showed the results yielded consistency, and no significant publication bias was observed for HCMV. The association between Herpes simplex virus type 2 (HSV-2) and AgP was inconclusive (2 studies: p = 0.20, OR = 3.46, 95% CI = 0.51-23.51). This meta-analysis suggests that HCMV and HSV-1 are significantly associated with AgP. However, due to the heterogeneity among studies these conclusions should be cautiously interpreted. There is insufficient evidence to draw any conclusion between EBV, HSV-2 and AgP based on the currently limited data.

Analysis of Maternal Risk Factors Associated With Congenital Vertebral Malformations

PubMed Central

Hesemann, Jennifer; Lauer, Emily; Ziska, Stephen; Noonan, Kenneth; Nemeth, Blaise; Scott-Schwoerer, Jessica; McCarty, Catherine; Rasmussen, Kristen; Goldberg, Jacob M.; Sund, Sarah; Eickhoff, Jens; Raggio, Cathleen L.; Giampietro, Philip F.

2014-01-01

Study Design A retrospective chart review of cases with congenital vertebral malformations (CVM) and controls with normal spine morphology. Objective To determine the relative contribution of maternal environmental factors (MEF) during pregnancy including maternal insulin dependent diabetes mellitus, valproic acid, alcohol, smoking, hyperthermia, twin gestation, assisted reproductive technology, in-vitro fertilization and maternal clomiphene usage to CVM development. Summary of Background Data Congenital vertebral malformations (CVM) represent defects in formation and segmentation of somites occurring with an estimated incidence of between 0.13–0.50 per 1000 live births. CVM may be associated with congenital scoliosis, Klippel-Feil syndrome, hemifacial microsomia and VACTERL syndromes, and represent significant morbidity due to pain and cosmetic disfigurement. Methods A multicenter retrospective chart review of 229 cases with CVM and 267 controls with normal spine morphology between the ages of 1–50 years was performed in order to obtain the odds ratio (OR) of MEF related to CVM among cases vs. controls. CVM due to an underlying syndrome associated with a known gene mutation or chromosome etiology were excluded. An imputation based analysis was performed in which subjects with no documentation of MEF history were treated as no maternal exposure.” Univariate and multivariate analysis was conducted to calculate the OR. Results Of the 229 total cases, 104 cases had single or multiple CVM without additional congenital malformations (CM) (Group 1) and 125 cases had single or multiple CVM and additional CM (Group 2). Nineteen percent of total cases had an identified MEF. The OR (95% CI, P-value) for MEF history for Group 1 was 6.0 (2.4–15.1, P<0.001) in the univariate analysis. The OR for MEF history in Group 2 was 9.1 (95%CI, P-value) (3.8–21.6, P<0.001) in the univariate analysis. The results were confirmed in the multivariate analysis, after adjusting for age, gender, and institution. Discussion These results support a hypothesis for an association between the above MEF during pregnancy and CVM and have implications for development of prevention strategies. Further prospective studies are needed to quantify association between CVM and specific MEF. PMID:23446706

Chronic osteomyelitis correlates with increased risk of acute pancreatitis in a case-control study in Taiwan.

PubMed

Lai, Shih-Wei; Lai, Hsueh-Chou; Lin, Cheng-Li; Liao, Kuan-Fu; Tseng, Chun-Hung

2015-07-01

The objective of this study was to examine the relationship between chronic osteomyelitis and acute pancreatitis in Taiwan. This was a population-based case-control study utilizing the database of the Taiwan National Health Insurance Program. We identified 7678 cases aged 20-84 with newly diagnosed acute pancreatitis during the period of 1998 to 2011. From the same database, 30,712 subjects without diagnosis of acute pancreatitis were selected as controls. The cases and controls were matched with sex, age and index year of diagnosing acute pancreatitis. The odds ratio with 95% confidence interval of acute pancreatitis associated with chronic osteomyelitis was examined by the multivariable unconditional logistic regression analysis. After adjustment for multiple confounders, the multivariable analysis showed that the adjusted odds ratio of acute pancreatitis was 1.93 for subjects with chronic osteomyelitis (95% confidence interval 1.01, 3.69), when compared with subjects without chronic osteomyelitis. Chronic osteomyelitis correlates with increased risk of acute pancreatitis. Patients with chronic osteomyelitis should be carefully monitored about the risk of acute pancreatitis. Copyright © 2015 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.

Factors associated with mother-to-child transmission of HIV-1 despite a maternal viral load <500 copies/ml at delivery: a case-control study nested in the French perinatal cohort (EPF-ANRS CO1).

PubMed

Tubiana, Roland; Le Chenadec, Jerome; Rouzioux, Christine; Mandelbrot, Laurent; Hamrene, Karima; Dollfus, Catherine; Faye, Albert; Delaugerre, Constance; Blanche, Stephane; Warszawski, Josiane

2010-02-15

The rate of mother-to-child transmission (MTCT) of human immunodeficiency virus (HIV) type 1 is as low as 0.5% in non-breast-feeding mothers who delivered at term while receiving antiretroviral therapy with a plasma viral load <500 copies/mL. This situation accounted for 20% of the infected children born during the period 1997-2006 in the French Perinatal Cohort. We aimed to identify factors associated with such residual transmission risk. We performed a case-control study nested in the aforementioned subpopulation of the French Perinatal Cohort. Nineteen case patients (transmitters) and 60 control subjects (nontransmitters) were included. Case patients and control subjects did not differ by geographical origin, gestational age at HIV diagnosis, type of antiretroviral therapy received, or elective Cesarean delivery. Case patients were less often receiving treatment at the time that they conceived pregnancy than control subjects (16% vs 45%; P=.017). A lower proportion of case patients had a viral load <500 copies/mL, compared with control subjects, at 14 weeks (0% vs 38.1%; P=.02), 28 weeks (7.7% vs 62.1%; P=.005), and 32 weeks: (21.4% vs 71.1%; P=.004). The difference remained significant when we restricted analysis to the 10 of 16 intrapartum transmission cases. In a multivariate analysis at 30+/-4 weeks adjusted for viral load, CD4(+) T cell count, and time at antiretroviral therapy initiation, viral load was the only factor independently associated with MTCT of HIV (adjusted odds ratio, 23.2; 95% confidence interval, 3.5-553; P<.001). Early and sustained control of viral load is associated with a decreasing residual risk of MTCT of HIV-1. Guidelines should take into account not only CD4(+) T cell count and risk of preterm delivery, but also baseline HIV-1 load for deciding when to start antiretroviral therapy during pregnancy.

Genome-wide association analysis accounting for environmental factors through propensity-score matching: application to stressful live events in major depressive disorder.

PubMed

Power, Robert A; Cohen-Woods, Sarah; Ng, Mandy Y; Butler, Amy W; Craddock, Nick; Korszun, Ania; Jones, Lisa; Jones, Ian; Gill, Michael; Rice, John P; Maier, Wolfgang; Zobel, Astrid; Mors, Ole; Placentino, Anna; Rietschel, Marcella; Aitchison, Katherine J; Tozzi, Federica; Muglia, Pierandrea; Breen, Gerome; Farmer, Anne E; McGuffin, Peter; Lewis, Cathryn M; Uher, Rudolf

2013-09-01

Stressful life events are an established trigger for depression and may contribute to the heterogeneity within genome-wide association analyses. With depression cases showing an excess of exposure to stressful events compared to controls, there is difficulty in distinguishing between "true" cases and a "normal" response to a stressful environment. This potential contamination of cases, and that from genetically at risk controls that have not yet experienced environmental triggers for onset, may reduce the power of studies to detect causal variants. In the RADIANT sample of 3,690 European individuals, we used propensity score matching to pair cases and controls on exposure to stressful life events. In 805 case-control pairs matched on stressful life event, we tested the influence of 457,670 common genetic variants on the propensity to depression under comparable level of adversity with a sign test. While this analysis produced no significant findings after genome-wide correction for multiple testing, we outline a novel methodology and perspective for providing environmental context in genetic studies. We recommend contextualizing depression by incorporating environmental exposure into genome-wide analyses as a complementary approach to testing gene-environment interactions. Possible explanations for negative findings include a lack of statistical power due to small sample size and conditional effects, resulting from the low rate of adequate matching. Our findings underscore the importance of collecting information on environmental risk factors in studies of depression and other complex phenotypes, so that sufficient sample sizes are available to investigate their effect in genome-wide association analysis. Copyright © 2013 Wiley Periodicals, Inc.

Semiparametric Bayesian analysis of gene-environment interactions with error in measurement of environmental covariates and missing genetic data.

PubMed

Lobach, Iryna; Mallick, Bani; Carroll, Raymond J

2011-01-01

Case-control studies are widely used to detect gene-environment interactions in the etiology of complex diseases. Many variables that are of interest to biomedical researchers are difficult to measure on an individual level, e.g. nutrient intake, cigarette smoking exposure, long-term toxic exposure. Measurement error causes bias in parameter estimates, thus masking key features of data and leading to loss of power and spurious/masked associations. We develop a Bayesian methodology for analysis of case-control studies for the case when measurement error is present in an environmental covariate and the genetic variable has missing data. This approach offers several advantages. It allows prior information to enter the model to make estimation and inference more precise. The environmental covariates measured exactly are modeled completely nonparametrically. Further, information about the probability of disease can be incorporated in the estimation procedure to improve quality of parameter estimates, what cannot be done in conventional case-control studies. A unique feature of the procedure under investigation is that the analysis is based on a pseudo-likelihood function therefore conventional Bayesian techniques may not be technically correct. We propose an approach using Markov Chain Monte Carlo sampling as well as a computationally simple method based on an asymptotic posterior distribution. Simulation experiments demonstrated that our method produced parameter estimates that are nearly unbiased even for small sample sizes. An application of our method is illustrated using a population-based case-control study of the association between calcium intake with the risk of colorectal adenoma development.

EPIBLASTER-fast exhaustive two-locus epistasis detection strategy using graphical processing units

PubMed Central

Kam-Thong, Tony; Czamara, Darina; Tsuda, Koji; Borgwardt, Karsten; Lewis, Cathryn M; Erhardt-Lehmann, Angelika; Hemmer, Bernhard; Rieckmann, Peter; Daake, Markus; Weber, Frank; Wolf, Christiane; Ziegler, Andreas; Pütz, Benno; Holsboer, Florian; Schölkopf, Bernhard; Müller-Myhsok, Bertram

2011-01-01

Detection of epistatic interaction between loci has been postulated to provide a more in-depth understanding of the complex biological and biochemical pathways underlying human diseases. Studying the interaction between two loci is the natural progression following traditional and well-established single locus analysis. However, the added costs and time duration required for the computation involved have thus far deterred researchers from pursuing a genome-wide analysis of epistasis. In this paper, we propose a method allowing such analysis to be conducted very rapidly. The method, dubbed EPIBLASTER, is applicable to case–control studies and consists of a two-step process in which the difference in Pearson's correlation coefficients is computed between controls and cases across all possible SNP pairs as an indication of significant interaction warranting further analysis. For the subset of interactions deemed potentially significant, a second-stage analysis is performed using the likelihood ratio test from the logistic regression to obtain the P-value for the estimated coefficients of the individual effects and the interaction term. The algorithm is implemented using the parallel computational capability of commercially available graphical processing units to greatly reduce the computation time involved. In the current setup and example data sets (211 cases, 222 controls, 299468 SNPs; and 601 cases, 825 controls, 291095 SNPs), this coefficient evaluation stage can be completed in roughly 1 day. Our method allows for exhaustive and rapid detection of significant SNP pair interactions without imposing significant marginal effects of the single loci involved in the pair. PMID:21150885

Association of vitamin D receptor BsmI, TaqI, FokI, and ApaI polymorphisms with susceptibility of chronic periodontitis: A systematic review and meta-analysis based on 38 case –control studies

PubMed Central

Mashhadiabbas, Fatemeh; Neamatzadeh, Hossein; Nasiri, Rezvan; Foroughi, Elnaz; Farahnak, Soudabeh; Piroozmand, Parisa; Mazaheri, Mahta; Zare-Shehneh, Masoud

2018-01-01

Background: There has been increasing interest in the study of the association between Vitamin D receptor (VDR) gene polymorphisms and risk of chronic periodontitis. However, the results remain inconclusive. To better understand the roles of VDR polymorphisms (BsmI, TaqI, FokI, and ApaI) in chronic periodontitis susceptibility, we conducted this systematic review and meta-analysis. Materials and Methods: The PubMed, Google Scholar, and Web of Science database were systemically searched to determine all the eligible studies about VDR polymorphisms and risk of chronic periodontitis up to April 2017. Odds ratio (OR) and 95% confidence interval (CI) were used to evaluate the associations between VDR polymorphisms and chronic periodontitis risk. All the statistical analyses were performed by Comprehensive Meta-Analysis. All P values were two-tailed with a significant level at 0.05. Results: Finally, a total of 38 case–control studies in 19 publications were identified which met our inclusion criteria. There are ten studies with 866 chronic periodontitis cases and 786 controls for BsmI, 16 studies with 1570 chronic periodontitis cases and 1676 controls for TaqI, five studies with 374 chronic periodontitis cases and 382 controls for FokI, and seven studies with 632 chronic periodontitis cases and 604 controls for ApaI. Overall, no significant association was observed between VDR gene BsmI, TaqI, FokI, and ApaI polymorphisms and risk of chronic periodontitis in any genetic model. Subgroup analysis stratified by ethnicity suggested a significant association between BsmI polymorphism and chronic periodontitis risk in the Caucasian subgroup under allele model (A vs. G: OR = 1.747, 95% CI = 1.099–2.778, P = 0.018). Further, no significant associations were observed when stratified by Hardy–Weinberg equilibrium status for BsmI, TaqI, and ApaI. Conclusion: Our results suggest that BsmI, TaqI, FokI, and ApaI polymorphisms in the VDR gene might not be associated with risk of chronic periodontitis in overall population. PMID:29922333

Cooperative Genome-Wide Analysis Shows Increased Homozygosity in Early Onset Parkinson's Disease

PubMed Central

Nalls, Michael A.; Martinez, Maria; Schulte, Claudia; Holmans, Peter; Gasser, Thomas; Hardy, John; Singleton, Andrew B.; Wood, Nicholas W.; Brice, Alexis; Heutink, Peter; Williams, Nigel; Morris, Huw R.

2012-01-01

Parkinson's disease (PD) occurs in both familial and sporadic forms, and both monogenic and complex genetic factors have been identified. Early onset PD (EOPD) is particularly associated with autosomal recessive (AR) mutations, and three genes, PARK2, PARK7 and PINK1, have been found to carry mutations leading to AR disease. Since mutations in these genes account for less than 10% of EOPD patients, we hypothesized that further recessive genetic factors are involved in this disorder, which may appear in extended runs of homozygosity. We carried out genome wide SNP genotyping to look for extended runs of homozygosity (ROHs) in 1,445 EOPD cases and 6,987 controls. Logistic regression analyses showed an increased level of genomic homozygosity in EOPD cases compared to controls. These differences are larger for ROH of 9 Mb and above, where there is a more than three-fold increase in the proportion of cases carrying a ROH. These differences are not explained by occult recessive mutations at existing loci. Controlling for genome wide homozygosity in logistic regression analyses increased the differences between cases and controls, indicating that in EOPD cases ROHs do not simply relate to genome wide measures of inbreeding. Homozygosity at a locus on chromosome19p13.3 was identified as being more common in EOPD cases as compared to controls. Sequencing analysis of genes and predicted transcripts within this locus failed to identify a novel mutation causing EOPD in our cohort. There is an increased rate of genome wide homozygosity in EOPD, as measured by an increase in ROHs. These ROHs are a signature of inbreeding and do not necessarily harbour disease-causing genetic variants. Although there might be other regions of interest apart from chromosome 19p13.3, we lack the power to detect them with this analysis. PMID:22427796

Homocysteine and risk of age-related macular degeneration: a systematic review and meta-analysis.

PubMed

Pinna, Antonio; Zaccheddu, Francesco; Boscia, Francesco; Carru, Ciriaco; Solinas, Giuliana

2018-05-01

There is still no agreement on total plasma homocysteine (tHcy) role in age-related macular degeneration (AMD), the leading cause of new blindness in industrialized countries. We performed a systematic review and meta-analysis of the published data on the correlation between tHcy and AMD. MEDLINE/PubMed and ISI Web of Sciences searches were performed according to MOOSE guidelines. Case-control studies were eligible for inclusion. Participants and controls were AMD patients and subjects without AMD. The main outcome measure was wet AMD. Homocysteine level was the main exposure variable. Data were pooled using a random-effects model. Twelve case-control studies were identified: 10 assessed wet AMD, four dry AMD, one early AMD, one late AMD, and one any AMD. As for wet AMD, there was a total of 453 cases and 514 controls. Mean tHcy was on average 1.1 μmol/l (95% confidence interval [CI] = 0.96-1.25) greater in wet AMD cases, but there was evidence of extreme between-study heterogeneity (p < 0.001, I 2  = 91.8%). In a model homogenous for age, including six wet AMD studies (214 cases, 274 controls), mean tHcy was on average 0.58 μmol/l (95% CI = 0.35-0.73) greater in the case group, a not statistically significant result (p = 0.144) associated with moderate heterogeneity (I 2  = 39.2%). Our meta-analysis indicates that there is some weak evidence that increased tHcy might be associated with wet AMD; however, this result should be interpreted cautiously, because of a marked between-study heterogeneity and the possible effect of publication bias. Future studies, preferably of cohort design, are necessary before any firm conclusions on the putative role of increased tHcy on AMD can be drawn. © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

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

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

PubMed

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

2017-01-03

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

Comprehensive review of genetic association studies and meta-analysis on miRNA polymorphisms and rheumatoid arthritis and systemic lupus erythematosus susceptibility.

PubMed

Fu, Lingyu; Jin, Lei; Yan, Lei; Shi, Jingpu; Wang, Hailong; Zhou, Bo; Wu, Xiaomei

2016-01-01

MicroRNAs (miRNAs), small RNA molecules, play a role in the development and differentiation of immune cells in both innate and adaptive immune responses. Our study was aimed to investigate the association between three miRNA polymorphism and rheumatoid arthritis (RA) or systemic lupus erythematosus (SLE) by using meta-analysis approach. A PubMed database search was conducted during August 2013 to identify case-control studies of miRNAs and RA or SLE risk. Two authors independently extracted information on the study design, the characteristics of the study participants, exposure and outcome assessments. The fix-effects and random-effects models were used for the risk estimates by Stata 11.0 software. Our meta-analysis of six case-control studies involving a total of 998 RA cases and 1493 controls identified no significant association between mir-146a rs2910164 and RA, with an overall OR of 0.843 (95% CI=0.642-1.105; CC vs. GG). No association was observed in three studies with a total of 1532 cases and 2168 controls between miR-146a rs2910164 and SLE risk (OR=0.911, 95% CI=0.710-1.171; CC vs. GG). Three studies with a total of 529 cases and 595 controls evaluated the mir-499 rs3746444 polymorphism and its association with RA. There was a decreased overall risk of RA under the allelic and genotypic models [OR=0.616, 95% CI=0.384-0.981, (T vs. C allele) and OR=0.386, 95% CI=0.226-0.659, (TT vs. CC)]. Two studies with 4826 cases and 4181 controls evaluated miR-146a rs57095329 and its association with SLE. There was a significant association between miR-146a rs57095329 and SLE (OR=1.263, 95% CI=1.136-1.405, G vs. A allele). The present meta-analysis suggests important roles for the mir-499 rs3746444 polymorphism in RA, especially in the Caucasian population and for miR-146a rs57095329 polymorphism in SLE. Further studies with large sample size are needed to confirm these associations. Copyright © 2014. Published by Elsevier Inc.

Systematic review and meta-analysis of association of smokeless tobacco and of betel quid without tobacco with incidence of oral cancer in South Asia and the Pacific.

PubMed

Gupta, Bhawna; Johnson, Newell W

2014-01-01

This systematic review and meta-analysis aimed to critically appraised data from comparable studies leading to quantitative assessment of any independent association between use of oral smokeless tobacco in any form, of betel quid without tobacco and of areca nut with incidence of oral cancer in South Asia and the Pacific. Studies (case control and/or cohort) were identified by searching Pub Med, CINAHL and Cochrane databases through June 2013 using the keywords oral cancer: chewing tobacco; smokeless tobacco; betel quid; betel quid without tobacco; areca nut; Asia, the Pacific and the reference lists of retrieved articles. A random effects model was used to compute adjusted summary OR(RE) for the main effect of these habits along with their corresponding 95% confidence intervals. To quantify the impact of between-study heterogeneity on adjusted main-effect summary OR(RE), Higgins' H and I2 statistics along with their 95% uncertainty intervals were used. Funnel plots and Egger's test were used to evaluate publication bias. Meta-analysis of fifteen case-control studies (4,553 cases; 8,632 controls) and four cohort studies (15,342) which met our inclusion criteria showed that chewing tobacco is significantly and independently associated with an increased risk of squamous-cell carcinoma of the oral cavity (adjusted main-effect summary for case- control studies OR(RE) = 7.46; 95% CI = 5.86-9.50, P<0.001), (adjusted main-effect summary for cohort studies RR = 5.48; 95% CI = 2.56-11.71, P<0.001). Furthermore, meta-analysis of fifteen case control studies (4,648 cases; 7,847 controls) has shown betel quid without tobacco to have an independent positive association with oral cancer, with OR = 2.82 (95% CI = 2.35-3.40, P<0.001). This is presumably due to the carcinogenicity of areca nut. There was no significant publication bias. There is convincing evidence that smokeless (aka chewing) tobacco, often used as a component of betel quid, and betel quid without tobacco, are both strong and independent risk factors for oral cancer in these populations. However, studies with better separation of the types of tobacco and the ways in which it is used, and studies with sufficient power to quantify dose-response relationships are still needed.

Three ulcerative colitis susceptibility loci are associated with primary sclerosing cholangitis and indicate a role for IL2, REL, and CARD9.

PubMed

Janse, Marcel; Lamberts, Laetitia E; Franke, Lude; Raychaudhuri, Soumya; Ellinghaus, Eva; Muri Boberg, Kirsten; Melum, Espen; Folseraas, Trine; Schrumpf, Erik; Bergquist, Annika; Björnsson, Einar; Fu, Jingyuan; Jan Westra, Harm; Groen, Harry J M; Fehrmann, Rudolf S N; Smolonska, Joanna; van den Berg, Leonard H; Ophoff, Roel A; Porte, Robert J; Weismüller, Tobias J; Wedemeyer, Jochen; Schramm, Christoph; Sterneck, Martina; Günther, Rainer; Braun, Felix; Vermeire, Severine; Henckaerts, Liesbet; Wijmenga, Cisca; Ponsioen, Cyriel Y; Schreiber, Stefan; Karlsen, Tom H; Franke, Andre; Weersma, Rinse K

2011-06-01

Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease characterized by inflammation and fibrosis of the bile ducts. Both environmental and genetic factors contribute to its pathogenesis. To further clarify its genetic background, we investigated susceptibility loci recently identified for ulcerative colitis (UC) in a large cohort of 1,186 PSC patients and 1,748 controls. Single nucleotide polymorphisms (SNPs) tagging 13 UC susceptibility loci were initially genotyped in 854 PSC patients and 1,491 controls from Benelux (331 cases, 735 controls), Germany (265 cases, 368 controls), and Scandinavia (258 cases, 388 controls). Subsequently, a joint analysis was performed with an independent second Scandinavian cohort (332 cases, 257 controls). SNPs at chromosomes 2p16 (P-value 4.12 × 10(-4) ), 4q27 (P-value 4.10 × 10(-5) ), and 9q34 (P-value 8.41 × 10(-4) ) were associated with PSC in the joint analysis after correcting for multiple testing. In PSC patients without inflammatory bowel disease (IBD), SNPs at 4q27 and 9q34 were nominally associated (P < 0.05). We applied additional in silico analyses to identify likely candidate genes at PSC susceptibility loci. To identify nonrandom, evidence-based links we used GRAIL (Gene Relationships Across Implicated Loci) analysis showing interconnectivity between genes in six out of in total nine PSC-associated regions. Expression quantitative trait analysis from 1,469 Dutch and UK individuals demonstrated that five out of nine SNPs had an effect on cis-gene expression. These analyses prioritized IL2, CARD9, and REL as novel candidates. We have identified three UC susceptibility loci to be associated with PSC, harboring the putative candidate genes REL, IL2, and CARD9. These results add to the scarce knowledge on the genetic background of PSC and imply an important role for both innate and adaptive immunological factors. Copyright © 2011 American Association for the Study of Liver Diseases.

Associated factors and outcomes for OXA-232 Carbapenem-resistant Enterobacteriaceae infections in a tertiary care centre in Mexico City: A case-control-control study.

PubMed

Torres-González, Pedro; Ortiz-Brizuela, Edgar; Cervera-Hernandez, Miguel Enrique; Bobadilla-Del Valle, Miriam; Martínez-Gamboa, Areli; Sifuentes-Osornio, José; Ponce-de-Leon, Alfredo

2016-10-01

We describe the outcomes and factors associated with OXA-232 producing carbapenem-resistant Enterobacteriaceae infections. A case-control-control study was performed; each case of infection by a carbapenem-resistant/OXA-232 (OXA-232-cases, n=27) was matched by isolation site, species, and date, with 2 cases of infection by carbapenem-susceptible/third-generation cephalosporin-susceptible (TGCS-controls, n=54) and 2 cases by carbapenem-susceptible/ESBL producing Enterobacteriaceae (ESBL-controls, n=54); 66% were urinary tract and 18.5% intra-abdominal infections. In the multivariable analysis with ESBL-controls, previous use β-lactam/β-lactamase antibiotics (OR 6.2; 95% CI 1.6-23.8) and, third-generation cephalosporins (OR 0.2; 95% CI 0.05-0.8) were associated with OXA-232 infection; with TGSC-controls previous use of β-lactam/β-lactamase antibiotics (OR 3.7; 95% 1.1-12.0) was associated. Among the OXA-232-cases, 29% received imipenem/cilastatin or meropenem, 11.1% ceftriaxone, 22.2% a carbapenem-based combination and 33.3% other antimicrobials as treatment. Previous β-lactam/β-lactamase antibiotics are associated with OXA-232 infections, and some may be treated with other active carbapenems or, in the absence of ESBL, third-generation cephalosporins. Copyright © 2016 Elsevier Inc. All rights reserved.

Is case-chaos methodology an appropriate alternative to conventional case-control studies for investigating outbreaks?

PubMed

Edelstein, Michael; Wallensten, Anders; Kühlmann-Berenzon, Sharon

2014-08-15

Case-chaos methodology is a proposed alternative to case-control studies that simulates controls by randomly reshuffling the exposures of cases. We evaluated the method using data on outbreaks in Sweden. We identified 5 case-control studies from foodborne illness outbreaks that occurred between 2005 and 2012. Using case-chaos methodology, we calculated odds ratios 1,000 times for each exposure. We used the median as the point estimate and the 2.5th and 97.5th percentiles as the confidence interval. We compared case-chaos matched odds ratios with their respective case-control odds ratios in terms of statistical significance. Using Spearman's correlation, we estimated the correlation between matched odds ratios and the proportion of cases exposed to each exposure and quantified the relationship between the 2 using a normal linear mixed model. Each case-control study identified an outbreak vehicle (odds ratios = 4.9-45). Case-chaos methodology identified the outbreak vehicle 3 out of 5 times. It identified significant associations in 22 of 113 exposures that were not associated with outcome and 5 of 18 exposures that were significantly associated with outcome. Log matched odds ratios correlated with their respective proportion of cases exposed (Spearman ρ = 0.91) and increased significantly with the proportion of cases exposed (b = 0.054). Case-chaos methodology missed the outbreak source 2 of 5 times and identified spurious associations between a number of exposures and outcome. Measures of association correlated with the proportion of cases exposed. We recommended against using case-chaos analysis during outbreak investigations. © The Author 2014. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Serratia marcescens Bacteremia: Nosocomial Cluster Following Narcotic Diversion.

PubMed

Schuppener, Leah M; Pop-Vicas, Aurora E; Brooks, Erin G; Duster, Megan N; Crnich, Christopher J; Sterkel, Alana K; Webb, Aaron P; Safdar, Nasia

2017-09-01

OBJECTIVE To describe the investigation and control of a cluster of Serratia marcescens bacteremia in a 505-bed tertiary-care center. METHODS Cluster cases were defined as all patients with S. marcescens bacteremia between March 2 and April 7, 2014, who were found to have identical or related blood isolates determined by molecular typing with pulsed-field gel electrophoresis. Cases were compared using bivariate analysis with controls admitted at the same time and to the same service as the cases, in a 4:1 ratio. RESULTS In total, 6 patients developed S. marcescens bacteremia within 48 hours after admission within the above period. Of these, 5 patients had identical Serratia isolates determined by molecular typing, and were included in a case-control study. Exposure to the post-anesthesia care unit was a risk factor identified in bivariate analysis. Evidence of tampered opioid-containing syringes on several hospital units was discovered soon after the initial cluster case presented, and a full narcotic diversion investigation was conducted. A nurse working in the post-anesthesia care unit was identified as the employee responsible for the drug diversion and was epidemiologically linked to all 5 patients in the cluster. No further cases were identified once the implicated employee's job was terminated. CONCLUSION Illicit drug use by healthcare workers remains an important mechanism for the development of bloodstream infections in hospitalized patients. Active mechanisms and systems should remain in place to prevent, detect, and control narcotic drug diversions and associated patient harm in the healthcare setting. Infect Control Hosp Epidemiol 2017;38:1027-1031.

Factors associated with tuberculosis cases in Semarang District, Indonesia: case-control study performed in the area where case detection rate was extremely low.

PubMed

Rahayu, Sri Ratna; Katsuyama, Hironobu; Demura, Masashi; Katsuyama, Midori; Ota, Yoko; Tanii, Hideji; Higashi, Tomomi; Semadi, Ngakan Putu Djaja; Saijoh, Kiyofumi

2015-07-01

Indonesia is ranked as the 4th highest contributor to tuberculosis (TB) in the world. Semarang District in Central Java displays extremely low case detection rate (CDR), possibly contributing to the local prevalence of TB. A case-control study was performed to explore the factors that cause such low CDR. We recruited 129 TB cases and 83 controls that visited the same centers and were not diagnosed with TB. The cases had 7.5 ± 2.3 symptoms/person on average, indicating the delay in diagnosis because the controls only displayed 1.0 ± 1.7. The multiple logistic regression analysis comparing the cases/controls extracted following factors as a risk to have TB: farmer, close contact with TB patients, ignorance of whether Bacillus Calmette-Guérin (BCG) was accepted or no, smoking, low income, a lot of people living in the same room, irregular hand wash before meals, not wash hands after blow, soil floor, and no sunlight and no ventilation in the house. Neither the cases nor the controls knew the symptoms and how to avoid TB infection, which probably caused the delay in diagnosis. It is difficult to change the current living conditions. Thus, the amendment of the community-based education program of TB seems to be required.

Effectiveness of quadrivalent human papillomavirus vaccine for the prevention of cervical abnormalities: case-control study nested within a population based screening programme in Australia.

PubMed

Crowe, Elizabeth; Pandeya, Nirmala; Brotherton, Julia M L; Dobson, Annette J; Kisely, Stephen; Lambert, Stephen B; Whiteman, David C

2014-03-04

To measure the effectiveness of the quadrivalent human papillomavirus (HPV) vaccine against cervical abnormalities four years after implementation of a nationally funded vaccination programme in Queensland, Australia. Case-control analysis of linked administrative health datasets. Queensland, Australia. Women eligible for free vaccination (aged 12-26 years in 2007) and attending for their first cervical smear test between April 2007 and March 2011. High grade cases were women with histologically confirmed high grade cervical abnormalities (n = 1062) and "other cases" were women with any other abnormality at cytology or histology (n = 10,887). Controls were women with normal cytology (n = 96,404). Exposure odds ratio (ratio of odds of antecedent vaccination (one, two, or three vaccine doses compared with no doses) among cases compared with controls), vaccine effectiveness ((1-adjusted odds ratio) × 100), and number needed to vaccinate to prevent one cervical abnormality at first screening round. We stratified by four age groups adjusted for follow-up time, year of birth, and measures of socioeconomic status and remoteness. The primary analysis concerned women whose first ever smear test defined their status as a case or a control. The adjusted odds ratio for exposure to three doses of HPV vaccine compared with no vaccine was 0.54 (95% confidence interval 0.43 to 0.67) for high grade cases and 0.66 (0.62 to 0.70) for other cases compared with controls with normal cytology, equating to vaccine effectiveness of 46% and 34%, respectively. The adjusted numbers needed to vaccinate were 125 (95% confidence interval 97 to 174) and 22 (19 to 25), respectively. The adjusted exposure odds ratios for two vaccine doses were 0.79 (95% confidence interval 0.64 to 0.98) for high grade cases and 0.79 (0.74 to 0.85) for other cases, equating to vaccine effectiveness of 21%. The quadrivalent HPV vaccine conferred statistically significant protection against cervical abnormalities in young women who had not started screening before the implementation of the vaccination programme in Queensland, Australia.

DNA Damage Analysis in Children with Non-syndromic Developmental Delay by Comet Assay.

PubMed

Susai, Surraj; Chand, Parkash; Ballambattu, Vishnu Bhat; Hanumanthappa, Nandeesha; Veeramani, Raveendranath

2016-05-01

Majority of the developmental delays in children are non-syndromic and they are believed to have an underlying DNA damage, though not well substantiated. Hence the present study was carried out to find out if there is any increased DNA damage in children with non-syndromic developmental delay by using the comet assay. The present case-control study was undertaken to assess the level of DNA damage in children with non syndromic developmental delay and compare the same with that of age and sex matched controls using submarine gel electrophoresis (Comet Assay). The blood from clinically diagnosed children with non syndromic developmental delay and controls were subjected for alkaline version of comet assay - Single cell gel electrophoresis using lymphocytes isolated from the peripheral blood. The comets were observed under a bright field microscope; photocaptured and scored using the Image J image quantification software. Comet parameters were compared between the cases and controls and statistical analysis and interpretation of results was done using the statistical software SPSS version 20. The mean comet tail length in cases and control was 20.77+7.659μm and 08.97+4.398μm respectively which was statistically significant (p<0.001). Other comet parameters like total comet length and % DNA in tail also showed a statistically significant difference (p < 0.001) between cases and controls. The current investigation unraveled increased levels of DNA damage in children with non syndromic developmental delay when compared to the controls.

A three-dimensional soft tissue analysis of Class III malocclusion: a case-controlled cross-sectional study.

PubMed

Johal, Ama; Chaggar, Amrit; Zou, Li Fong

2018-03-01

The present study used the optical surface laser scanning technique to compare the facial features of patients aged 8-18 years presenting with Class I and Class III incisor relationship in a case-control design. Subjects with a Class III incisor relationship, aged 8-18 years, were age and gender matched with Class I control and underwent a 3-dimensional (3-D) optical surface scan of the facial soft tissues. Landmark analysis revealed Class III subjects displayed greater mean dimensions compared to the control group most notably between the ages of 8-10 and 17-18 years in both males and females, in respect of antero-posterior (P = 0.01) and vertical (P = 0.006) facial dimensions. Surface-based analysis, revealed the greatest difference in the lower facial region, followed by the mid-face, whilst the upper face remained fairly consistent. Significant detectable differences were found in the surface facial features of developing Class III subjects.

A mega-analysis of genome-wide association studies for major depressive disorder.

PubMed

Ripke, Stephan; Wray, Naomi R; Lewis, Cathryn M; Hamilton, Steven P; Weissman, Myrna M; Breen, Gerome; Byrne, Enda M; Blackwood, Douglas H R; Boomsma, Dorret I; Cichon, Sven; Heath, Andrew C; Holsboer, Florian; Lucae, Susanne; Madden, Pamela A F; Martin, Nicholas G; McGuffin, Peter; Muglia, Pierandrea; Noethen, Markus M; Penninx, Brenda P; Pergadia, Michele L; Potash, James B; Rietschel, Marcella; Lin, Danyu; Müller-Myhsok, Bertram; Shi, Jianxin; Steinberg, Stacy; Grabe, Hans J; Lichtenstein, Paul; Magnusson, Patrik; Perlis, Roy H; Preisig, Martin; Smoller, Jordan W; Stefansson, Kari; Uher, Rudolf; Kutalik, Zoltan; Tansey, Katherine E; Teumer, Alexander; Viktorin, Alexander; Barnes, Michael R; Bettecken, Thomas; Binder, Elisabeth B; Breuer, René; Castro, Victor M; Churchill, Susanne E; Coryell, William H; Craddock, Nick; Craig, Ian W; Czamara, Darina; De Geus, Eco J; Degenhardt, Franziska; Farmer, Anne E; Fava, Maurizio; Frank, Josef; Gainer, Vivian S; Gallagher, Patience J; Gordon, Scott D; Goryachev, Sergey; Gross, Magdalena; Guipponi, Michel; Henders, Anjali K; Herms, Stefan; Hickie, Ian B; Hoefels, Susanne; Hoogendijk, Witte; Hottenga, Jouke Jan; Iosifescu, Dan V; Ising, Marcus; Jones, Ian; Jones, Lisa; Jung-Ying, Tzeng; Knowles, James A; Kohane, Isaac S; Kohli, Martin A; Korszun, Ania; Landen, Mikael; Lawson, William B; Lewis, Glyn; Macintyre, Donald; Maier, Wolfgang; Mattheisen, Manuel; McGrath, Patrick J; McIntosh, Andrew; McLean, Alan; Middeldorp, Christel M; Middleton, Lefkos; Montgomery, Grant M; Murphy, Shawn N; Nauck, Matthias; Nolen, Willem A; Nyholt, Dale R; O'Donovan, Michael; Oskarsson, Högni; Pedersen, Nancy; Scheftner, William A; Schulz, Andrea; Schulze, Thomas G; Shyn, Stanley I; Sigurdsson, Engilbert; Slager, Susan L; Smit, Johannes H; Stefansson, Hreinn; Steffens, Michael; Thorgeirsson, Thorgeir; Tozzi, Federica; Treutlein, Jens; Uhr, Manfred; van den Oord, Edwin J C G; Van Grootheest, Gerard; Völzke, Henry; Weilburg, Jeffrey B; Willemsen, Gonneke; Zitman, Frans G; Neale, Benjamin; Daly, Mark; Levinson, Douglas F; Sullivan, Patrick F

2013-04-01

Prior genome-wide association studies (GWAS) of major depressive disorder (MDD) have met with limited success. We sought to increase statistical power to detect disease loci by conducting a GWAS mega-analysis for MDD. In the MDD discovery phase, we analyzed more than 1.2 million autosomal and X chromosome single-nucleotide polymorphisms (SNPs) in 18 759 independent and unrelated subjects of recent European ancestry (9240 MDD cases and 9519 controls). In the MDD replication phase, we evaluated 554 SNPs in independent samples (6783 MDD cases and 50 695 controls). We also conducted a cross-disorder meta-analysis using 819 autosomal SNPs with P<0.0001 for either MDD or the Psychiatric GWAS Consortium bipolar disorder (BIP) mega-analysis (9238 MDD cases/8039 controls and 6998 BIP cases/7775 controls). No SNPs achieved genome-wide significance in the MDD discovery phase, the MDD replication phase or in pre-planned secondary analyses (by sex, recurrent MDD, recurrent early-onset MDD, age of onset, pre-pubertal onset MDD or typical-like MDD from a latent class analyses of the MDD criteria). In the MDD-bipolar cross-disorder analysis, 15 SNPs exceeded genome-wide significance (P<5 × 10(-8)), and all were in a 248 kb interval of high LD on 3p21.1 (chr3:52 425 083-53 822 102, minimum P=5.9 × 10(-9) at rs2535629). Although this is the largest genome-wide analysis of MDD yet conducted, its high prevalence means that the sample is still underpowered to detect genetic effects typical for complex traits. Therefore, we were unable to identify robust and replicable findings. We discuss what this means for genetic research for MDD. The 3p21.1 MDD-BIP finding should be interpreted with caution as the most significant SNP did not replicate in MDD samples, and genotyping in independent samples will be needed to resolve its status.

Rabies outbreak in Greece during 2012-2014: use of Geographical Information System for analysis, risk assessment and control.

PubMed

Giannakopoulos, A; Valiakos, G; Papaspyropoulos, K; Dougas, G; Korou, L M; Tasioudi, K E; Fthenakis, G C; Hutchings, M R; Kaimaras, D; Tsokana, C N; Iliadou, P; Spyrou, V; Tzani, M; Birtsas, P; Kostoglou, P; Sokos, C; Doudounakis, S; Yon, L; Hannant, D; Artois, M; Tsiodras, S; Hadjichristodoulou, C; Billinis, C

2016-10-01

The objectives of this work were (i) geographical analysis of the 2012-2014 outbreak of rabies in Greece using GIS and (ii) comparative analysis of animal cases with data of potential human exposure to rabies together with environmental data, in order to provide information for risk assessment, effective monitoring and control. Most animal cases (40/48) involved red foxes, while domestic animals were also diagnosed with rabies. Overall, 80% of the cases were diagnosed in central northern Greece; 75% of the cases were diagnosed in low altitudes (<343·5 m), within a distance of 1 km from human settlements. Median distance from livestock farms was 201·25 m. Most people potentially exposed to rabies (889/1060) presented with dog bite injuries. Maximum entropy analysis revealed that distance from farms contributed the highest percentage in defining environmental niche profiles for rabid foxes. Oral vaccination programmes were implemented in 24 administrative units of the country during 2013 and 2014, covering a total surface area of ~60 000 km2. Rabies re-occurrence in Greece emphasizes the need for ongoing surveillance in cross-border areas and in areas with intense human activity.

Stabilization of nonlinear systems using sampled-data output-feedback fuzzy controller based on polynomial-fuzzy-model-based control approach.

PubMed

Lam, H K

2012-02-01

This paper investigates the stability of sampled-data output-feedback (SDOF) polynomial-fuzzy-model-based control systems. Representing the nonlinear plant using a polynomial fuzzy model, an SDOF fuzzy controller is proposed to perform the control process using the system output information. As only the system output is available for feedback compensation, it is more challenging for the controller design and system analysis compared to the full-state-feedback case. Furthermore, because of the sampling activity, the control signal is kept constant by the zero-order hold during the sampling period, which complicates the system dynamics and makes the stability analysis more difficult. In this paper, two cases of SDOF fuzzy controllers, which either share the same number of fuzzy rules or not, are considered. The system stability is investigated based on the Lyapunov stability theory using the sum-of-squares (SOS) approach. SOS-based stability conditions are obtained to guarantee the system stability and synthesize the SDOF fuzzy controller. Simulation examples are given to demonstrate the merits of the proposed SDOF fuzzy control approach.

Design and analysis of multiple diseases genome-wide association studies without controls.

PubMed

Chen, Zhongxue; Huang, Hanwen; Ng, Hon Keung Tony

2012-11-15

In genome-wide association studies (GWAS), multiple diseases with shared controls is one of the case-control study designs. If data obtained from these studies are appropriately analyzed, this design can have several advantages such as improving statistical power in detecting associations and reducing the time and cost in the data collection process. In this paper, we propose a study design for GWAS which involves multiple diseases but without controls. We also propose corresponding statistical data analysis strategy for GWAS with multiple diseases but no controls. Through a simulation study, we show that the statistical association test with the proposed study design is more powerful than the test with single disease sharing common controls, and it has comparable power to the overall test based on the whole dataset including the controls. We also apply the proposed method to a real GWAS dataset to illustrate the methodologies and the advantages of the proposed design. Some possible limitations of this study design and testing method and their solutions are also discussed. Our findings indicate that the proposed study design and statistical analysis strategy could be more efficient than the usual case-control GWAS as well as those with shared controls. Copyright © 2012 Elsevier B.V. All rights reserved.

New class of control laws for robotic manipulators. I - Nonadaptive case. II - Adaptive case

NASA Technical Reports Server (NTRS)

Wen, John T.; Bayard, David S.

1988-01-01

A new class of exponentially stabilizing control laws for joint level control of robot arms is discussed. Closed-loop exponential stability has been demonstrated for both the set point and tracking control problems by a slight modification of the energy Lyapunov function and the use of a lemma which handles third-order terms in the Lyapunov function derivatives. In the second part, these control laws are adapted in a simple fashion to achieve asymptotically stable adaptive control. The analysis addresses the nonlinear dynamics directly without approximation, linearization, or ad hoc assumptions, and uses a parameterization based on physical (time-invariant) quantities.

The effects of particulate air pollution on daily deaths: a multi-city case crossover analysis

PubMed Central

Schwartz, J

2004-01-01

Background: Numerous studies have reported that day-to-day changes in particulate air pollution are associated with day-to-day changes in deaths. Recently, several reports have indicated that the software used to control for season and weather in some of these studies had deficiencies. Aims: To investigate the use of the case-crossover design as an alternative. Methods: This approach compares the exposure of each case to their exposure on a nearby day, when they did not die. Hence it controls for seasonal patterns and for all slowly varying covariates (age, smoking, etc) by matching rather than complex modelling. A key feature is that temperature can also be controlled by matching. This approach was applied to a study of 14 US cities. Weather and day of the week were controlled for in the regression. Results: A 10 µg/m3 increase in PM10 was associated with a 0.36% increase in daily deaths from internal causes (95% CI 0.22% to 0.50%). Results were little changed if, instead of symmetrical sampling of control days the time stratified method was applied, when control days were matched on temperature, or when more lags of winter time temperatures were used. Similar results were found using a Poisson regression, but the case-crossover method has the advantage of simplicity in modelling, and of combining matched strata across multiple locations in a single stage analysis. Conclusions: Despite the considerable differences in analytical design, the previously reported associations of particles with mortality persisted in this study. The association appeared quite linear. Case-crossover designs represent an attractive method to control for season and weather by matching. PMID:15550600

The Multiple Control of Verbal Behavior

PubMed Central

Michael, Jack; Palmer, David C; Sundberg, Mark L

2011-01-01

Amid the novel terms and original analyses in Skinner's Verbal Behavior, the importance of his discussion of multiple control is easily missed, but multiple control of verbal responses is the rule rather than the exception. In this paper we summarize and illustrate Skinner's analysis of multiple control and introduce the terms convergent multiple control and divergent multiple control. We point out some implications for applied work and discuss examples of the role of multiple control in humor, poetry, problem solving, and recall. Joint control and conditional discrimination are discussed as special cases of multiple control. We suggest that multiple control is a useful analytic tool for interpreting virtually all complex behavior, and we consider the concepts of derived relations and naming as cases in point. PMID:22532752

Cost-Effectiveness Analysis of Three Leprosy Case Detection Methods in Northern Nigeria

PubMed Central

Ezenduka, Charles; Post, Erik; John, Steven; Suraj, Abdulkarim; Namadi, Abdulahi; Onwujekwe, Obinna

2012-01-01

Background Despite several leprosy control measures in Nigeria, child proportion and disability grade 2 cases remain high while new cases have not significantly reduced, suggesting continuous spread of the disease. Hence, there is the need to review detection methods to enhance identification of early cases for effective control and prevention of permanent disability. This study evaluated the cost-effectiveness of three leprosy case detection methods in Northern Nigeria to identify the most cost-effective approach for detection of leprosy. Methods A cross-sectional study was carried out to evaluate the additional benefits of using several case detection methods in addition to routine practice in two north-eastern states of Nigeria. Primary and secondary data were collected from routine practice records and the Nigerian Tuberculosis and Leprosy Control Programme of 2009. The methods evaluated were Rapid Village Survey (RVS), Household Contact Examination (HCE) and Traditional Healers incentive method (TH). Effectiveness was measured as number of new leprosy cases detected and cost-effectiveness was expressed as cost per case detected. Costs were measured from both providers' and patients' perspectives. Additional costs and effects of each method were estimated by comparing each method against routine practise and expressed as incremental cost-effectiveness ratio (ICER). All costs were converted to the U.S. dollar at the 2010 exchange rate. Univariate sensitivity analysis was used to evaluate uncertainties around the ICER. Results The ICER for HCE was $142 per additional case detected at all contact levels and it was the most cost-effective method. At ICER of $194 per additional case detected, THs method detected more cases at a lower cost than the RVS, which was not cost-effective at $313 per additional case detected. Sensitivity analysis showed that varying the proportion of shared costs and subsistent wage for valuing unpaid time did not significantly change the results. Conclusion Complementing routine practice with household contact examination is the most cost-effective approach to identify new leprosy cases and we recommend that, depending on acceptability and feasibility, this intervention is introduced for improved case detection in Northern Nigeria. PMID:23029580

Maintenance of Occupational Control: The Case of Professions.

ERIC Educational Resources Information Center

Child, John; Fulk, Janet

1982-01-01

Contemporary conditions relevant to the maintenance of occupational control are examined for five professions (accounting, architecture, civil engineering, law, and medicine) in the United Kingdom and the United States as an impetus for the analysis of control by occupations in general. (Author/CT)

Combining evidence from multiple electronic health care databases: performances of one-stage and two-stage meta-analysis in matched case-control studies.

PubMed

La Gamba, Fabiola; Corrao, Giovanni; Romio, Silvana; Sturkenboom, Miriam; Trifirò, Gianluca; Schink, Tania; de Ridder, Maria

2017-10-01

Clustering of patients in databases is usually ignored in one-stage meta-analysis of multi-database studies using matched case-control data. The aim of this study was to compare bias and efficiency of such a one-stage meta-analysis with a two-stage meta-analysis. First, we compared the approaches by generating matched case-control data under 5 simulated scenarios, built by varying: (1) the exposure-outcome association; (2) its variability among databases; (3) the confounding strength of one covariate on this association; (4) its variability; and (5) the (heterogeneous) confounding strength of two covariates. Second, we made the same comparison using empirical data from the ARITMO project, a multiple database study investigating the risk of ventricular arrhythmia following the use of medications with arrhythmogenic potential. In our study, we specifically investigated the effect of current use of promethazine. Bias increased for one-stage meta-analysis with increasing (1) between-database variance of exposure effect and (2) heterogeneous confounding generated by two covariates. The efficiency of one-stage meta-analysis was slightly lower than that of two-stage meta-analysis for the majority of investigated scenarios. Based on ARITMO data, there were no evident differences between one-stage (OR = 1.50, CI = [1.08; 2.08]) and two-stage (OR = 1.55, CI = [1.12; 2.16]) approaches. When the effect of interest is heterogeneous, a one-stage meta-analysis ignoring clustering gives biased estimates. Two-stage meta-analysis generates estimates at least as accurate and precise as one-stage meta-analysis. However, in a study using small databases and rare exposures and/or outcomes, a correct one-stage meta-analysis becomes essential. Copyright © 2017 John Wiley & Sons, Ltd.

A case-control study and meta-analysis confirm glucokinase regulatory gene rs780094 is a risk factor for gestational diabetes mellitus.

PubMed

Jamalpour, Sajad; Zain, Shamsul Mohd; Mosavat, Maryam; Mohamed, Zahurin; Omar, Siti Zawiah

2018-04-15

Although the influence of a common variant in the glucokinase regulatory gene (GCKR rs780094) in type 2 diabetes mellitus has been well documented, less data however, is available of its role in gestational diabetes mellitus (GDM). We carried out a case control study to assess the association between GCKR rs780094 and GDM in the Asian, and also a meta-analysis to further assess the strength of the association. Demographic, clinical and genotype data were determined for 1122 women (267 cases and 855 controls) recruited from the University of Malaya Medical Centre in the Klang Valley, Kuala Lumpur. Relevant articles were identified from Pubmed, Embase, MEDLINE, and Web of Science. Extraction of data was carried out and summary estimates of the association between rs780094 and GDM were examined. The frequency of risk allele C was significantly higher in the cases than controls (OR 1.34, 95% CI 1.09-1.66, P = 0.006). The C allele was also associated with increased level of random 2-hour fasting plasma glucose and pregravid body mass index. Meta-analysis further confirmed the association of the GCKR rs780094 with GDM (OR 1.32, 95% CI 1.14-1.52, P = 0.0001). This study strongly suggests that GCKR rs780094-C is associated with increased risk of GDM. Copyright © 2018 Elsevier B.V. All rights reserved.

Coffee Consumption and the Risk of Thyroid Cancer: A Systematic Review and Meta-Analysis.

PubMed

Han, Mi Ah; Kim, Jin Hwa

2017-01-27

An inverse association has been reported between coffee consumption and the risk of several cancers. However, the association between coffee and thyroid cancer is controversial. Thus, this study aimed to evaluate the association between coffee consumption and the risk of thyroid cancer through a systematic review and meta-analysis. Published studies were examined from PubMed, Embase, Cochrane Central, and the reference lists of the retrieved articles. The summary odds ratio (OR) for the association between coffee consumption was categorized as highest versus lowest consumption, and thyroid cancer risk was calculated using a fixed effects model. Subgroup analyses by study design, geographic location, source of controls, and adjusted variables were performed. A total of 1039 thyroid cancer cases and 220,816 controls were identified from five case-control studies and two cohort studies. The summary OR for the association between coffee consumption and thyroid cancer risk was 0.88 (95% confidence interval (CI) = 0.71-1.07). There was no significant heterogeneity among the study results (I² = 0%, p = 0.79). However, the beneficial effect of coffee consumption on thyroid cancer was found only in hospital-based case-control studies (OR= 0.59, 95% CI= 0.37-0.93). There was no significant association between coffee consumption and thyroid cancer risk according to our meta-analysis results. These findings should be interpreted with caution because of potential biases and confounding variables. Further prospective studies with a larger number of cases are encouraged to confirm these results.

Comparisons of serum miRNA expression profiles in patients with diabetic retinopathy and type 2 diabetes mellitus.

PubMed

Ma, Jianping; Wang, Jufang; Liu, Yanfen; Wang, Changyi; Duan, Donghui; Lu, Nanjia; Wang, Kaiyue; Zhang, Lu; Gu, Kaibo; Chen, Sihan; Zhang, Tao; You, Dingyun; Han, Liyuan

2017-02-01

The aim of this study was to compare the expression levels of serum miRNAs in diabetic retinopathy and type 2 diabetes mellitus. Serum miRNA expression profiles from diabetic retinopathy cases (type 2 diabetes mellitus patients with diabetic retinopathy) and type 2 diabetes mellitus controls (type 2 diabetes mellitus patients without diabetic retinopathy) were examined by miRNA-specific microarray analysis. Quantitative real-time polymerase chain reaction was used to validate the significantly differentially expressed serum miRNAs from the microarray analysis of 45 diabetic retinopathy cases and 45 age-, sex-, body mass index- and duration-of-diabetes-matched type 2 diabetes mellitus controls. The relative changes in serum miRNA expression levels were analyzed using the 2-ΔΔCt method. A total of 5 diabetic retinopathy cases and 5 type 2 diabetes mellitus controls were included in the miRNA-specific microarray analysis. The serum levels of miR-3939 and miR-1910-3p differed significantly between the two groups in the screening stage; however, quantitative real-time polymerase chain reaction did not reveal significant differences in miRNA expression for 45 diabetic retinopathy cases and their matched type 2 diabetes mellitus controls. Our findings indicate that miR-3939 and miR-1910-3p may not play important roles in the development of diabetic retinopathy; however, studies with a larger sample size are needed to confirm our findings.

N-Acetyltransferase Polymorphism and Risk of Colorectal Adenoma and Cancer: A Pooled Analysis of Variations from 59 Studies

PubMed Central

Wang, Xiaoxue; Chen, Yizhi; Li, Rong; Zhang, Ying; Luo, Rongcheng

2012-01-01

Background There have been an increasing number of studies with evidence suggesting that the N-acetyltransferase 1 (NAT1) and N-acetyltransferase 2 (NAT2) genotypes may be implicated in the development of colorectal cancer (CRC) and colorectal adenoma (CRA). So far the published data on this association has remained controversial, however. We performed a meta-analysis of case-cohort and case-control studies using a subset of the published data, with an aim to derive a better understanding of the underlying relationship. Methods/Principal Findings A literature search was performed using Medline database for relevant studies published through October 31, 2011. A total of 39 publications were selected for this meta-analysis, including 11,724 cases and 16,215 controls for CRC, and 3,701 cases and 5,149 controls for CRA. In our pooled analysis of all these studies, the results of our meta-analysis suggested that the NAT1 genotype was not significantly associated with an elevated CRC risk (OR 0.99, 95% CI 0.91–1.07). We also found that individuals with the rapid NAT2 genotype did have an elevated risk of CRC (OR 1.07, 95% CI 1.01–1.13). There was no evidence for an association between the NAT1 and 2 rapid genotype and an elevated CRA risk (NAT1: OR 1.14, 95% CI 0.99–1.29; NAT2: OR 0.94, 95% CI 0.86–1.03). Conclusion This meta-analysis suggests that individuals with NAT2 genotype had an elevated risk of CRC. There was no evidence for the association between NAT1 and 2 rapid genotype and CRA risk. PMID:22905173

Analysis of Rare, Exonic Variation amongst Subjects with Autism Spectrum Disorders and Population Controls

PubMed Central

Liu, Li; Sabo, Aniko; Neale, Benjamin M.; Nagaswamy, Uma; Stevens, Christine; Lim, Elaine; Bodea, Corneliu A.; Muzny, Donna; Reid, Jeffrey G.; Banks, Eric; Coon, Hillary; DePristo, Mark; Dinh, Huyen; Fennel, Tim; Flannick, Jason; Gabriel, Stacey; Garimella, Kiran; Gross, Shannon; Hawes, Alicia; Lewis, Lora; Makarov, Vladimir; Maguire, Jared; Newsham, Irene; Poplin, Ryan; Ripke, Stephan; Shakir, Khalid; Samocha, Kaitlin E.; Wu, Yuanqing; Boerwinkle, Eric; Buxbaum, Joseph D.; Cook, Edwin H.; Devlin, Bernie; Schellenberg, Gerard D.; Sutcliffe, James S.; Daly, Mark J.; Gibbs, Richard A.; Roeder, Kathryn

2013-01-01

We report on results from whole-exome sequencing (WES) of 1,039 subjects diagnosed with autism spectrum disorders (ASD) and 870 controls selected from the NIMH repository to be of similar ancestry to cases. The WES data came from two centers using different methods to produce sequence and to call variants from it. Therefore, an initial goal was to ensure the distribution of rare variation was similar for data from different centers. This proved straightforward by filtering called variants by fraction of missing data, read depth, and balance of alternative to reference reads. Results were evaluated using seven samples sequenced at both centers and by results from the association study. Next we addressed how the data and/or results from the centers should be combined. Gene-based analyses of association was an obvious choice, but should statistics for association be combined across centers (meta-analysis) or should data be combined and then analyzed (mega-analysis)? Because of the nature of many gene-based tests, we showed by theory and simulations that mega-analysis has better power than meta-analysis. Finally, before analyzing the data for association, we explored the impact of population structure on rare variant analysis in these data. Like other recent studies, we found evidence that population structure can confound case-control studies by the clustering of rare variants in ancestry space; yet, unlike some recent studies, for these data we found that principal component-based analyses were sufficient to control for ancestry and produce test statistics with appropriate distributions. After using a variety of gene-based tests and both meta- and mega-analysis, we found no new risk genes for ASD in this sample. Our results suggest that standard gene-based tests will require much larger samples of cases and controls before being effective for gene discovery, even for a disorder like ASD. PMID:23593035

Combining epidemiology and biomechanics in sports injury prevention research: a new approach for selecting suitable controls.

PubMed

Finch, Caroline F; Ullah, Shahid; McIntosh, Andrew S

2011-01-01

Several important methodological issues need to be considered when designing sports injury case-control studies. Major design goals for case-control studies include the accounting for prior injury risk exposure, and optimal definitions of both cases and suitable controls are needed to ensure this. This article reviews methodological aspects of published sports injury case-control studies, particularly with regard to the selection of controls. It argues for a new approach towards selecting controls for case-control studies that draws on an interface between epidemiological and biomechanical concepts. A review was conducted to identify sport injury case-control studies published in the peer-review literature during 1985-2008. Overall, 32 articles were identified, of which the majority related to upper or lower extremity injuries. Matching considerations were used for control selection in 16 studies. Specific mention of application of biomechanical principles in the selection of appropriate controls was absent from all studies, including those purporting to evaluate the benefits of personal protective equipment to protect against impact injury. This is a problem because it could lead to biased conclusions, as cases and controls are not fully comparable in terms of similar biomechanical impact profiles relating to the injury incident, such as site of the impact on the body. The strength of the conclusions drawn from case-control studies, and the extent to which results can be generalized, is directly influenced by the definition and recruitment of cases and appropriate controls. Future studies should consider the interface between epidemiological and biomechanical concepts when choosing appropriate controls to ensure that proper adjustment of prior exposure to injury risk is made. To provide necessary guidance for the optimal selection of controls in case-control studies of interventions to prevent sports-related impact injury, this review outlines a new case-control selection strategy that reflects the importance of biomechanical considerations, which ensures that controls are selected based on the presence of the same global injury mechanism as the cases. To summarize, the general biomechanical principles that should apply to the selection of controls in future case-control studies are as follows: (i) each control must have been exposed to the same global injury mechanism as the case, (e.g. head impact, fall onto outstretched arm); and (ii) intrinsic (individual) factors (e.g. age, sex, skill level) that might modify the person's response to the relevant biomechanical loads are adjusted when either selecting the controls or are in the analysis phase. The same considerations for control selection apply to other study designs such as matched cohort studies or case-crossover studies.

Hepatitis C virus infections in oral lichen planus: a systematic review and meta-analysis.

PubMed

Alaizari, N A; Al-Maweri, S A; Al-Shamiri, H M; Tarakji, B; Shugaa-Addin, B

2016-09-01

A role for hepatitis C virus in oral lichen planus has been postulated. This systematic review and meta-analysis of the existing epidemiological studies was conducted to determine if there is a correlation between oral lichen planus and hepatitis C virus infection. We examined the association between hepatitis C virus and oral lichen planus by conducting a systematic review and meta-analysis of case-control studies that examined the prevalence of anti-HCV antibodies in the serum of cases and controls. We searched PubMed, Embase and The Cochrane Library databases from 2005 to January 2015. Associations were measured using random-effect odds ratios (ORs) combined with 95% confidence intervals. Nineteen eligible studies, encompassing 1807 cases of OLP and 2519 controls, were retrieved and included in this review. The summary estimate OR for all studies was 6.07 (95% CI: 2.73-13.48), showing a statistically significant difference in the proportion of HCV seropositivity among oral lichen planus patients, compared with controls and substantial heterogeneity between studies (I(2) = 65%) as a result of a variety of geographical distributions. The association of hepatitis C virus infection with oral lichen planus emphasizes the importance of hepatitis C virus screening in oral lichen planus patients. © 2015 Australian Dental Association.

Analysis of binary responses with outcome-specific misclassification probability in genome-wide association studies.

PubMed

Rekaya, Romdhane; Smith, Shannon; Hay, El Hamidi; Farhat, Nourhene; Aggrey, Samuel E

2016-01-01

Errors in the binary status of some response traits are frequent in human, animal, and plant applications. These error rates tend to differ between cases and controls because diagnostic and screening tests have different sensitivity and specificity. This increases the inaccuracies of classifying individuals into correct groups, giving rise to both false-positive and false-negative cases. The analysis of these noisy binary responses due to misclassification will undoubtedly reduce the statistical power of genome-wide association studies (GWAS). A threshold model that accommodates varying diagnostic errors between cases and controls was investigated. A simulation study was carried out where several binary data sets (case-control) were generated with varying effects for the most influential single nucleotide polymorphisms (SNPs) and different diagnostic error rate for cases and controls. Each simulated data set consisted of 2000 individuals. Ignoring misclassification resulted in biased estimates of true influential SNP effects and inflated estimates for true noninfluential markers. A substantial reduction in bias and increase in accuracy ranging from 12% to 32% was observed when the misclassification procedure was invoked. In fact, the majority of influential SNPs that were not identified using the noisy data were captured using the proposed method. Additionally, truly misclassified binary records were identified with high probability using the proposed method. The superiority of the proposed method was maintained across different simulation parameters (misclassification rates and odds ratios) attesting to its robustness.

Exposure to residential electric and magnetic fields and risk of childhood leukemia.

PubMed

London, S J; Thomas, D C; Bowman, J D; Sobel, E; Cheng, T C; Peters, J M

1991-11-01

The relation between exposure to electric and magnetic fields in the home, as assessed by measurements, wiring configuration, and self-reported appliance use, and risk of leukemia was investigated in a case-control study among children from birth to age 10 years in Los Angeles County, California. Cases were ascertained through a population-based tumor registry from 1980 to 1987. Controls were drawn from friends and by random digit dialing. Interviews were obtained from 232 cases and 232 controls. Available for analysis were measurements of the magnetic field in the child's bedroom over 24 hours or longer (164 cases and 144 controls), spot measurements of magnetic and electric fields (140 cases and 109 controls), and wiring configuration (219 cases and 207 controls). No clear associations between leukemia risk and measured magnetic or electric fields were seen. An association between the Denver Wertheimer-Leeper wiring configuration and childhood leukemia risk was observed (odds ratio for very high relative to very low current and underground configuration combined = 2.15, 95% confidence interval 1.08-4.28; p for trend = 0.008) and was not substantially altered by adjustment for potential confounding factors. Cases were more likely than controls to report use of several appliances that produce high electric and magnetic fields. Our results support an association between childhood leukemia risk and wiring configuration, but not direct measurements of electric and magnetic fields.

Robust dynamic inversion controller design and analysis (using the X-38 vehicle as a case study)

NASA Astrophysics Data System (ADS)

Ito, Daigoro

A new way to approach robust Dynamic Inversion controller synthesis is addressed in this paper. A Linear Quadratic Gaussian outer-loop controller improves the robustness of a Dynamic Inversion inner-loop controller in the presence of uncertainties. Desired dynamics are given by the dynamic compensator, which shapes the loop. The selected dynamics are based on both performance and stability robustness requirements. These requirements are straightforwardly formulated as frequency-dependent singular value bounds during synthesis of the controller. Performance and robustness of the designed controller is tested using a worst case time domain quadratic index, which is a simple but effective way to measure robustness due to parameter variation. Using this approach, a lateral-directional controller for the X-38 vehicle is designed and its robustness to parameter variations and disturbances is analyzed. It is found that if full state measurements are available, the performance of the designed lateral-directional control system, measured by the chosen cost function, improves by approximately a factor of four. Also, it is found that the designed system is stable up to a parametric variation of 1.65 standard deviation with the set of uncertainty considered. The system robustness is determined to be highly sensitive to the dihedral derivative and the roll damping coefficients. The controller analysis is extended to the nonlinear system where both control input displacements and rates are bounded. In this case, the considered nonlinear system is stable up to 48.1° in bank angle and 1.59° in sideslip angle variations, indicating it is more sensitive to variations in sideslip angle than in bank angle. This nonlinear approach is further extended for the actuator failure mode analysis. The results suggest that the designed system maintains a high level of stability in the event of aileron failure. However, only 35% or less of the original stability range is maintained for the rudder failure case. Overall, this combination of controller synthesis and robustness criteria compares well with the mu-synthesis technique. It also is readily accessible to the practicing engineer, in terms of understanding and use.

The Impact of Baseline Trend Control on Visual Analysis of Single-Case Data

ERIC Educational Resources Information Center

Mercer, Sterett H.; Sterling, Heather E.

2012-01-01

The impact of baseline trend control on visual analyses of AB intervention graphs was examined with simulated data at various values of baseline trend, autocorrelation, and effect size. Participants included 202 undergraduate students with minimal training in visual analysis and 10 graduate students and faculty with more training and experience in…

Method for evaluating multiple mediators: mediating effects of smoking and COPD on the association between the CHRNA5-A3 variant and lung cancer risk.

PubMed

Wang, Jian; Spitz, Margaret R; Amos, Christopher I; Wu, Xifeng; Wetter, David W; Cinciripini, Paul M; Shete, Sanjay

2012-01-01

A mediation model explores the direct and indirect effects between an independent variable and a dependent variable by including other variables (or mediators). Mediation analysis has recently been used to dissect the direct and indirect effects of genetic variants on complex diseases using case-control studies. However, bias could arise in the estimations of the genetic variant-mediator association because the presence or absence of the mediator in the study samples is not sampled following the principles of case-control study design. In this case, the mediation analysis using data from case-control studies might lead to biased estimates of coefficients and indirect effects. In this article, we investigated a multiple-mediation model involving a three-path mediating effect through two mediators using case-control study data. We propose an approach to correct bias in coefficients and provide accurate estimates of the specific indirect effects. Our approach can also be used when the original case-control study is frequency matched on one of the mediators. We employed bootstrapping to assess the significance of indirect effects. We conducted simulation studies to investigate the performance of the proposed approach, and showed that it provides more accurate estimates of the indirect effects as well as the percent mediated than standard regressions. We then applied this approach to study the mediating effects of both smoking and chronic obstructive pulmonary disease (COPD) on the association between the CHRNA5-A3 gene locus and lung cancer risk using data from a lung cancer case-control study. The results showed that the genetic variant influences lung cancer risk indirectly through all three different pathways. The percent of genetic association mediated was 18.3% through smoking alone, 30.2% through COPD alone, and 20.6% through the path including both smoking and COPD, and the total genetic variant-lung cancer association explained by the two mediators was 69.1%.

RNA-Seq Analysis of Gene Expression, Viral Pathogen, and B-Cell/T-Cell Receptor Signatures in Complex Chronic Disease.

PubMed

Bouquet, Jerome; Gardy, Jennifer L; Brown, Scott; Pfeil, Jacob; Miller, Ruth R; Morshed, Muhammad; Avina-Zubieta, Antonio; Shojania, Kam; McCabe, Mark; Parker, Shoshana; Uyaguari, Miguel; Federman, Scot; Tang, Patrick; Steiner, Ted; Otterstater, Michael; Holt, Rob; Moore, Richard; Chiu, Charles Y; Patrick, David M

2017-02-15

Chronic fatigue syndrome (CFS) remains poorly understood. Although infections are speculated to trigger the syndrome, a specific infectious agent and underlying pathophysiological mechanism remain elusive. In a previous study, we described similar clinical phenotypes in CFS patients and alternatively diagnosed chronic Lyme syndrome (ADCLS) patients—individuals diagnosed with Lyme disease by testing from private Lyme specialty laboratories but who test negative by reference 2-tiered serologic analysis. Here, we performed blinded RNA-seq analysis of whole blood collected from 25 adults diagnosed with CFS and 13 ADCLS patients, comparing these cases to 25 matched controls and 11 patients with well-controlled systemic lupus erythematosus (SLE). Samples were collected at patient enrollment and not during acute symptom flares. RNA-seq data were used to study host gene expression, B-cell/T-cell receptor profiles (BCR/TCR), and potential viral infections. No differentially expressed genes (DEGs) were found to be significant when CFS or ADCLS cases were compared to controls. Forty-two DEGs were found when SLE cases were compared to controls, consistent with activation of interferon signaling pathways associated with SLE disease. BCR/TCR repertoire analysis did not show significant differences between CFS and controls or ADCLS and controls. Finally, viral sequences corresponding to anelloviruses, human pegivirus 1, herpesviruses, and papillomaviruses were detected in RNA-seq data, but proportions were similar (P = .73) across all genus-level taxonomic categories. Our observations do not support a theory of transcriptionally mediated immune cell dysregulation in CFS and ADCLS, at least outside of periods of acute symptom flares. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.

A discriminant analysis prediction model of non-syndromic cleft lip with or without cleft palate based on risk factors.

PubMed

Li, Huixia; Luo, Miyang; Luo, Jiayou; Zheng, Jianfei; Zeng, Rong; Du, Qiyun; Fang, Junqun; Ouyang, Na

2016-11-23

A risk prediction model of non-syndromic cleft lip with or without cleft palate (NSCL/P) was established by a discriminant analysis to predict the individual risk of NSCL/P in pregnant women. A hospital-based case-control study was conducted with 113 cases of NSCL/P and 226 controls without NSCL/P. The cases and the controls were obtained from 52 birth defects' surveillance hospitals in Hunan Province, China. A questionnaire was administered in person to collect the variables relevant to NSCL/P by face to face interviews. Logistic regression models were used to analyze the influencing factors of NSCL/P, and a stepwise Fisher discriminant analysis was subsequently used to construct the prediction model. In the univariate analysis, 13 influencing factors were related to NSCL/P, of which the following 8 influencing factors as predictors determined the discriminant prediction model: family income, maternal occupational hazards exposure, premarital medical examination, housing renovation, milk/soymilk intake in the first trimester of pregnancy, paternal occupational hazards exposure, paternal strong tea drinking, and family history of NSCL/P. The model had statistical significance (lambda = 0.772, chi-square = 86.044, df = 8, P < 0.001). Self-verification showed that 83.8 % of the participants were correctly predicted to be NSCL/P cases or controls with a sensitivity of 74.3 % and a specificity of 88.5 %. The area under the receiver operating characteristic curve (AUC) was 0.846. The prediction model that was established using the risk factors of NSCL/P can be useful for predicting the risk of NSCL/P. Further research is needed to improve the model, and confirm the validity and reliability of the model.

Use of the Ishikawa diagram in a case-control analysis to assess the causes of a diffuse lamellar keratitis outbreak.

PubMed

Lira, Luis Henrique; Hirai, Flávio E; Oliveira, Marivaldo; Portellinha, Waldir; Nakano, Eliane Mayumi

2017-01-01

To identify the causes of a diffuse lamellar keratitis (DLK) outbreak using a systematic search tool in a case-control analysis. An Ishikawa diagram was used to guide physicians to determine the potential risk factors involved in this outbreak. Coherence between the occurrences and each possible cause listed in the diagram was verified, and the total number of eyes at risk was used to calculate the proportion of affected eyes. Multivariate analysis was performed using logistic regression to determine the independent effect of the risk factors, after controlling for confounders and test interactions. All DLK cases were reported in 2007 between June 13 and December 21; during this period, 3,698 procedures were performed. Of the 1,682 flap-related procedures, 204 eyes of 141 individuals presented with DLK. No direct relationship was observed between the occurrence of DLK and the presence of any specific factors; however, flap-lifting enhancements, procedures performed during the morning shift, and non-use of therapeutic contact lenses after the surgery were significantly related to higher occurrence percentages of this condition. The Ishikawa diagram, like most quality tools, is a visualization and knowledge organization tool. This systematization allowed the investigators to thoroughly assess all the possible causes of DLK outbreak. A clear view of the entire surgical logistics permitted even more rigid management of the main factors involved in the process and, as a result, highlighted factors that deserved attention. The case-control analysis on every factor raised by the Ishikawa diagram indicated that the commonly suspected factors such as biofilm contamination of the water reservoir in autoclaves, the air-conditioning filter system, glove powder, microkeratome motor oil, and gentian violet markers were not related to the outbreak.

BNSF San Bernardino case study : positive train control risk assessment.

DOT National Transportation Integrated Search

2014-09-01

The Federal Railroad Administration funded the BNSF San Bernardino Case Study to verify its Generalized Train Movement : Simulator (GTMS) risk assessment capabilities on a planned implementation of the I-ETMS PTC system. The analysis explicitly : sim...

Aircraft Loss-of-Control: Analysis and Requirements for Future Safety-Critical Systems and Their Validation

NASA Technical Reports Server (NTRS)

Belcastro, Christine M.

2011-01-01

Loss of control remains one of the largest contributors to fatal aircraft accidents worldwide. Aircraft loss-of-control accidents are complex, resulting from numerous causal and contributing factors acting alone or more often in combination. Hence, there is no single intervention strategy to prevent these accidents. This paper summarizes recent analysis results in identifying worst-case combinations of loss-of-control accident precursors and their time sequences, a holistic approach to preventing loss-of-control accidents in the future, and key requirements for validating the associated technologies.

Personal hair dyes use and risk of glioma: a meta-analysis

PubMed Central

Shao, Chuan; Qi, Zhen-Yu; Hui, Guo-Zhen; Wang, Zhong

2013-01-01

Background and Objective: Use of hair dyes for glioma risk has been investigated in numerous epidemiological studies, but the evidence is inconsistent. Therefore, a meta-analysis was performed to estimate the association between hair dyes use and glioma risk. Methods: We searched PubMed and EMBASE databases without any limitations, covering all papers published by the end of March 8, 2013. Cohort and case-control studies reporting relative risk estimates (RRs) with corresponding 95% confidence intervals (CIs) (or data to calculate them) on this issue were included. Random effects models were used to calculate the pooled RRs and corresponding 95% CIs. Results: Four case-control and two cohort studies were included in this meta-analysis. The summary RRs and 95 % CIs for ever users of any hair dyes were 1.132 (0.887-1.446) for all studies, 1.291 (0.938-1.777) for case-control studies, and 0.903 (0.774-1.054) for cohort studies. In the subgroup analysis by geographic regions and sex, the similar results were detected. No significant associations were also observed among the studies which reported data involving permanent hair dye use and duration of any hair dye use. Conclusion: In summary, the results of our study demonstrated that hair dyes use is not associated with risk of glioma. PMID:24179568

A Meta-Analysis of the Association between DNMT1 Polymorphisms and Cancer Risk.

PubMed

Li, Hao; Liu, Jing-Wei; Sun, Li-Ping; Yuan, Yuan

2017-01-01

Previous studies have examined the associations of DNA methyltransferase 1 ( DNMT1 ) polymorphisms, including single nucleotide polymorphisms rs16999593 (T/C), rs2228611 (G/A), and rs2228612 (A/G), with cancer risk. However, the results are inconclusive. The aim of this meta-analysis is to elucidate the associations between DNMT1 polymorphisms and cancer susceptibility. The PubMed, Embase, Web of Science, and Chinese National Knowledge Infrastructure databases were searched systematically to identify potentially eligible reports. Odd ratios and 95% confidence intervals were used to evaluate the strength of association between three DNMT1 polymorphisms and cancer risk. A total of 16 studies were finally included in the meta-analysis, namely, nine studies of 3378 cases and 4244 controls for rs16999593, 11 studies of 3643 cases and 3866 controls for rs2228611, and three studies of 1343 cases and 1309 controls for rs2228612. The DNMT1 rs2228612 (A/G) polymorphism was significantly related to cancer risk in the recessive model. The meta-analysis also suggested that DNMT1 rs16999593 (T/C) may be associated with gastric cancer, while rs2228611 (G/A) may be associated with breast cancer. In future research, large-scale and well-designed studies are required to verify these findings.

[Risk factors for anorexia in children].

PubMed

Liu, Wei-Xiao; Lang, Jun-Feng; Zhang, Qin-Feng

2016-11-01

To investigate the risk factors for anorexia in children, and to reduce the prevalence of anorexia in children. A questionnaire survey and a case-control study were used to collect the general information of 150 children with anorexia (case group) and 150 normal children (control group). Univariate analysis and multivariate logistic stepwise regression analysis were performed to identify the risk factors for anorexia in children. The results of the univariate analysis showed significant differences between the case and control groups in the age in months when supplementary food were added, feeding pattern, whether they liked meat, vegetables and salty food, whether they often took snacks and beverages, whether they liked to play while eating, and whether their parents asked them to eat food on time (P<0.05). The results of the multivariate logistic regression analysis showed that late addition of supplementary food (OR=5.408), high frequency of taking snacks and/or drinks (OR=11.813), and eating while playing (OR=6.654) were major risk factors for anorexia in children. Liking of meat (OR=0.093) and vegetables (OR=0.272) and eating on time required by parents (OR=0.079) were protective factors against anorexia in children. Timely addition of supplementary food, a proper diet, and development of children's proper eating and living habits can reduce the incidence of anorexia in children.

Acute pulmonary emphysema in death by hanging: a morphometric digital study.

PubMed

Castiglioni, Claudia; Baumann, Pia; Fracasso, Tony

2016-09-01

Acute pulmonary emphysema (APE) has been described in cases of mechanical asphyxia such as ligature or manual strangulation but not in cases of hanging. In this study, we wanted to verify by morphometric digital analysis of lung tissue whether APE occurs in death by hanging.We investigated 16 cases of hanging (eight complete, eight incomplete), 10 cases of freshwater drowning (positive control group), and 10 cases of acute external bleeding (negative control group). Tissue sections were obtained from each pulmonary lobe. For each slide, five fields were randomly selected. The area of every alveolar space was measured by image analysis software. The mean alveolar area (MAA) was calculated for each group.In incomplete hanging, MAA was significantly higher than that observed in complete hanging and similar to the one observed in freshwater drowning.APE in cases of incomplete hanging can be considered as a sign of vitality. The high number of conditions that can cause alveolar distension (that were excluded in this study) limits the applicability of this vital sign in the routine forensic practice.

Hyperthyroidism association with SLE, lessons from real-life data--A case-control study.

PubMed

Watad, Abdulla; Cohen, Arnon D; Comaneshter, Doron; Tekes-Manova, Dorit; Amital, Howard

2016-01-01

Despite the frequently encountered association between thyroid disease and systemic lupus erythematosus (SLE) is well known, it is of surprise that only several reports compromised of small population size support this observation. To investigate the association of comorbid SLE and hyperthyroidism. Using the database of the largest health maintenance organization (HMO) in Israel, the Clalit Health Services, we searched for the co-existence of SLE and hyperthyroidism. Patients with SLE were compared with age- and sex-matched controls regarding the prevalence of hyperthyroidism in a case-control study. Chi-square and t-tests were used for univariate analysis and a logistic regression model was used for multivariate analysis. The study included 5018 patients with SLE and 25,090 age- and sex- matched controls. The prevalence of hyperthyroidism in patients with SLE was increased compared with the prevalence in controls (2.59% and 0.91%, respectively, p < 0.001). In a multivariate analysis, SLE was associated with hyperthyroidism (odds ratio 2.52, 95% confidence interval 2.028-3.137). Patients with SLE have a greater prevalence of hyperthyroidism than matched controls. Therefore, physicians treating patients with SLE should be aware of this possibility of this thyroid dysfunction.

Coffee Drinking and the Risk of Endometrial Cancer: An Updated Meta-Analysis of Observational Studies.

PubMed

Lukic, Marko; Guha, Neela; Licaj, Idlir; van den Brandt, Piet A; Stayner, Leslie Thomas; Tavani, Alessandra; Weiderpass, Elisabete

2018-01-01

Several compounds contained in coffee have been found to suppress carcinogenesis in experimental studies. We conducted a dose-response meta-analysis to assess the impact of coffee consumption on the risk of endometrial cancer. We searched MEDLINE and EMBASE databases for studies published up to August 2016. Using random effects models, we estimated summary relative risks (RR) for cohort studies and odds ratios (OR) for case-control studies with 95% confidence intervals (CI). Dose-response analyses were conducted by using generalized least square trend estimation. We identified 12 cohort studies and 8 case-control studies eligible for inclusion, contributing with 11,663 and 2,746 endometrial cancer cases, respectively. The summary RR for highest compared with lowest coffee intake was 0.74 (95% CI: 0.68-0.81; p heterogeneity = 0.09, I 2 = 32%). The corresponding summary RR among cohort studies was 0.78 (95% CI: 0.71-0.85; p heterogeneity = 0.14, I 2 = 31.9%) and 0.63 (95% CI: 0.53-0.76; p heterogeneity = 0.57, I 2 = 0%) for case-control studies. One-cup increment per day was associated with 3% risk reduction (95% CI: 2-4%) in cohort studies and 12% (95% CI: 5-18%) in case-control studies. After pooling the results from 5 cohort studies, the association remained significant only in women with body mass index over 30 (RR = 0.71, 95% CI: 0.61-0.81). The results from our meta-analysis strengthen the evidence of a protective effect of coffee consumption on the risk of EC and further suggest that increased coffee intake might be particularly beneficial for women with obesity.

Update on the effect of exogenous hormone use on glioma risk in women: a meta-analysis of case-control and cohort studies.

PubMed

Lan, Yu-Long; Wang, Xun; Lou, Jia-Cheng; Ma, Bin-Bin; Xing, Jin-Shan; Zou, Shuang; Zhang, Bo

2018-04-01

Various studies have confirmed the important roles of endogenous hormones in the development of gliomas, while the roles of exogenous hormones remain controversial. Based on case-control studies and cohort studies, a meta-analysis was exerted to explore the effect of two exogenous hormones use (HRT: hormone replacement therapy; OC: oral contraceptives) on glioma risk. 16 eligible studies, including 11 case-control studies and 5 cohort studies, containing 8055027 women, were included in our study. All included studies have reported the relative risks (RRs) or odds ratios (ORs), and 95% confidence intervals (CIs). We use the fixed-effects model to calculate the estimated overall risk. In case-control studies, the risk of glioma was lower in women who had ever been treated with an exogenous hormone than in the control group (HRT: OR 0.91, 95% CI 0.84-0.99; OC: OR 0.99, 95% CI 0.91-1.07). In research of cohort studies, similar results have been obtained (HRT: RR 0.95, 95% CI 0.83-1.08; OC: RR 0.75, 95% CI 0.66-0.84). Our study further confirmed that the use of exogenous hormones has an important impact on the risk of glioma in women. However, more prospective studies are needed to further confirm this conclusion.

Risk factors associated with the community-acquired colonization of extended-spectrum beta-lactamase (ESBL) positive Escherichia Coli. an exploratory case-control study.

PubMed

Leistner, Rasmus; Meyer, Elisabeth; Gastmeier, Petra; Pfeifer, Yvonne; Eller, Christoph; Dem, Petra; Schwab, Frank

2013-01-01

The number of extended-spectrum beta-lactamase (ESBL) positive (+) Escherichia coli is increasing worldwide. In contrast with many other multidrug-resistant bacteria, it is suspected that they predominantly spread within the community. The objective of this study was to assess factors associated with community-acquired colonization of ESBL (+) E. coli. We performed a matched case-control study at the Charité University Hospital Berlin between May 2011 and January 2012. Cases were defined as patients colonized with community-acquired ESBL (+) E. coli identified <72 h after hospital admission. Controls were patients that carried no ESBL-positive bacteria but an ESBL-negative E.coli identified <72 h after hospital admission. Two controls per case were chosen from potential controls according to admission date. Case and control patients completed a questionnaire assessing nutritional habits, travel habits, household situation and language most commonly spoken at home (mother tongue). An additional rectal swab was obtained together with the questionnaire to verify colonization status. Genotypes of ESBL (+) E. coli strains were determined by PCR and sequencing. Risk factors associated with ESBL (+) E. coli colonization were analyzed by a multivariable conditional logistic regression analysis. We analyzed 85 cases and 170 controls, respectively. In the multivariable analysis, speaking an Asian language most commonly at home (OR = 13.4, CI 95% 3.3-53.8; p<0.001) and frequently eating pork (≥ 3 meals per week) showed to be independently associated with ESBL colonization (OR = 3.5, CI 95% 1.8-6.6; p<0.001). The most common ESBL genotypes were CTX-M-1 with 44% (n = 37), CTX-M-15 with 28% (n = 24) and CTX-M-14 with 13% (n = 11). An Asian mother tongue and frequently consuming certain types of meat like pork can be independently associated with the colonization of ESBL-positive bacteria. We found neither frequent consumption of poultry nor previous use of antibiotics to be associated with ESBL colonization.

A case study in nonlinear dynamics and control of articulated spacecraft: The Space Station Freedom with a mobile remote manipulator system

NASA Technical Reports Server (NTRS)

Bennett, William H.; Kwatny, Harry G.; Lavigna, Chris; Blankenship, Gilmer

1994-01-01

The following topics are discussed: (1) modeling of articulated spacecraft as multi-flex-body systems; (2) nonlinear attitude control by adaptive partial feedback linearizing (PFL) control; (3) attitude dynamics and control for SSF/MRMS; and (4) performance analysis results for attitude control of SSF/MRMS.

Association of IL-10-1082A/G Polymorphism with Ischemic Stroke: Evidence from a Case-Control Study to an Updated Meta-Analysis.

PubMed

Liu, Xu; Li, Qu; Zhu, Ruixia; He, Zhiyi

2017-06-01

Interleukin-10 (IL-10) plays a vital part in the pathophysiology of vascular inflammation. Several studies have investigated the potential association between the IL-10-1082A/G polymorphism and the risk of ischemic stroke where the inflammatory process is involved, but the conclusions have been inconsistent. Three hundred eighty-six ischemic stroke patients and 386 healthy controls were recruited in the study. Genotyping was conducted by using the polymerase chain reaction-ligation detection reaction method. A meta-analysis was then performed by pooling our data with previous published studies. In our case-control study, a lack of association was revealed between IL-10-1082A/G and ischemic stroke (p > 0.05). When combined with previous studies, however, a significant relationship between IL-10-1082A/G and ischemic stroke risk was found (G vs. A: OR = 0.73, 95% CI = 0.60-0.88, p < 0.01; GG vs. AA: OR = 0.61, 95% CI = 0.49-0.76, p < 0.01; GG+AG vs. AA: OR = 0.70, 95% CI = 0.54-0.91, p < 0.01; GG vs. AG+AA: OR = 0.68, 95% CI = 0.52-0.89, p < 0.01), as well as in subgroup analyses. Sensitivity analysis and publication bias assessment supported the reliability of the results from the meta-analysis. Evidence from a case-control study to an updated meta-analysis suggests that the IL-10-1082A/G polymorphism is associated with ischemic stroke susceptibility.

[The protective efficacy of BCG against leprosy in São Paulo, Brazil].

PubMed

Lombardi, C; Pedrazzani, E S; Pedrazzani, J C; Ferreira Filho, P; Zicker, F

1995-11-01

The protection against leprosy conferred by BCG vaccination was evaluated in a case-control study. Selected for the study were 97 patients under 16 years of age who had been diagnosed with leprosy (cases) and 385 healthy persons (controls), who were matched according to sex, age, place of residence, and type of contact (intra- or extradomicilliary). The cases were selected from a register of active cases as well as a series of new leprosy patients treated in 50 centers in the city of São Paulo, Brasil. To estimate the protective effect of BCG, the prevalences of BCG scars among cases and controls were compared. The presence of one or more scars was associated with a protective efficacy of 90% (95% confidence interval: 78%-96%). Stratified analysis by age group, sex, socioeconomic level, and clinical form of leprosy did not reveal any important differences in the protection conferred by the vaccine. The significance of these findings and the appropriateness of using BCG in leprosy control programs is discussed.

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

PubMed

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

2006-04-01

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

Correcting for batch effects in case-control microbiome studies

PubMed Central

Gibbons, Sean M.; Duvallet, Claire

2018-01-01

High-throughput data generation platforms, like mass-spectrometry, microarrays, and second-generation sequencing are susceptible to batch effects due to run-to-run variation in reagents, equipment, protocols, or personnel. Currently, batch correction methods are not commonly applied to microbiome sequencing datasets. In this paper, we compare different batch-correction methods applied to microbiome case-control studies. We introduce a model-free normalization procedure where features (i.e. bacterial taxa) in case samples are converted to percentiles of the equivalent features in control samples within a study prior to pooling data across studies. We look at how this percentile-normalization method compares to traditional meta-analysis methods for combining independent p-values and to limma and ComBat, widely used batch-correction models developed for RNA microarray data. Overall, we show that percentile-normalization is a simple, non-parametric approach for correcting batch effects and improving sensitivity in case-control meta-analyses. PMID:29684016

Dietary and other risk factors in the aetiology of cholelithiasis: a case control study.

PubMed

Linos, A D; Daras, V; Linos, D A; Kekis, V; Tsoukas, M M; Golematis, V

1989-10-01

We studied the effect of dietary factors and a variety of other risk factors on the development of cholelithiasis through a case control study. The study involved 96 cases and 118 age and sex matched controls. All cases and controls were interviewed with regard to a variety of risk factors and frequency of consumption of over 100 food items. Analysis was done both by chi square and a multiple logistic regression model. From all the dietary factors the only ones that showed a positive statistically significantly (p less than 0.05) association was consumption of animal fat as expressed by eating all visible fat on the meat and using butter on the table. Interestingly high consumption of olive oil had a negative (protective) association with the disease. A negative association was also found with smoking and holding a job demanding hard labor.

A case control study of senile cataract in a hospital based population.

PubMed

Badrinath, S S; Sharma, T; Biswas, J; Srinivas, V

1996-12-01

A case-control study (244 cases and 264 controls) was done during 1986-89 on a hospital based population to evaluate the risk factors associated with the etiology of senile cataract. Patient with age between 40-60 years, visual acuity of 6/9 or less, and presence of lenticular opacity of senile origin were included as cases. Age matched individuals with absence of lenticular opacity made up the controls. Multivariate logistic regression analysis revealed that higher systolic BP and number of meals were significantly (P < or = 0.05) associated with presence of senile cataract; whereas higher weight, education and income, and utilization of cooking water had a significant protective effect against senile cataract. The present study helps the clinician to understand the possible risk factors associated with the development of senile cataract and could be helpful in designing a intervention strategy in future.

Dietary and Other Risk Factors in The Aetiology of Cholelithiasis: A Case Control Study

PubMed Central

Daras, V.; Linos, D. A.; Kekis, V.; Tsoukas, M. M.; Golematis, V.

1989-01-01

We studied the effect of dietary factors and a variety of other risk factors on the development of cholelithiasis through a case control study. The study involved 96 cases and 118 age and sex matched controls. All cases and controls were interviewed with regard to a variety of risk factors and frequency of consumption of over 100 food items. Analysis was done both by chi square and a multiple logistic regression model. From all the dietry factors the only ones that showed a positive statistically signficantly (p<0.05) association was consumption of animal fat as expressed by eating all visible fat on the meat and using butter on the table. Interestingly high consumption of olive oil had a negative (protective) association with the disease. A negative association was also found with smoking and holding a job demanding hard labor. PMID:2487388

LPV H-infinity Control for the Longitudinal Dynamics of a Flexible Air-Breathing Hypersonic Vehicle

NASA Astrophysics Data System (ADS)

Hughes, Hunter Douglas

This dissertation establishes the method needed to synthesize and simulate an Hinfinity Linear Parameter-Varying (LPV) controller for a flexible air-breathing hypersonic vehicle model. A study was conducted to gain the understanding of the elastic effects on the open loop system. It was determined that three modes of vibration would be suitable for the hypersonic vehicle model. It was also discovered from the open loop study that there is strong coupling in the hypersonic vehicle states, especially between the angle of attack, pitch rate, pitch attitude, and the exible modes of the vehicle. This dissertation outlines the procedure for synthesizing a full state feedback Hinfinity LPV controller for the hypersonic vehicle. The full state feedback study looked at both velocity and altitude tracking for the exible vehicle. A parametric study was conducted on each of these controllers to see the effects of changing the number of gridding points in the parameter space and changing the parameter variation rate limits in the system on the robust performance of the controller. As a result of the parametric study, a 7 x 7 grid ranging from Mach 7 to Mach 9 in velocity and from 70,000 feet to 90,000 feet in altitude, and a parameter variation rate limit of [.5 200]T was used for both the velocity tracking and altitude tracking cases. The resulting Hinfinity robust performances were gamma = 2.2224 for the velocity tracking case and = 1:7582 for the altitude tracking case. A linear analysis was then conducted on five different selected trim points from the Hinfinity LPV controller. This was conducted for the velocity tracking and altitude tracking cases. The results of linear analysis show that there is a slight difference in the response of the Hinfinity LPV controller and the fixed point H infinity controller. For the tracking task, the Hinfinity controller responds more quickly, and has a lower Hinfinity performance value. Next, the H infinity LPV controller was simulated using the nonlinear flexible hypersonic model for both the velocity tracking and altitude tracking cases. Both of these cases were subject to a ramp input and a multi-step input both with and without perturbation in the model. The results of the simulation show that the tracking state follows the command signal successfully though the perturbed system does show some higher frequency characteristics in the non-tracking states. It was discovered that there is an issue with integral windup when switching takes place in the controller, so an algorithm was implemented to reset the integration of the error on the tracking state when the switch takes place. It was also seen that there was a decline in altitude when tracking velocity, and a large change in velocity that occurred during altitude tracking. These results lead to the decision to include a unity gain regulation state on velocity for the altitude tracking and the altitude for the velocity tracking during the output feedback control synthesis. The procedure for synthesizing an output feedback H infinity LPV controller for the hypersonic vehicle is also discussed in this dissertation. The output feedback design looked at velocity tracking and altitude tracking with rigid body motion variables for both the exible and rigid body hypersonic vehicle models. As with the full state feedback controller, a parametric study was conducted on each of these controllers to determine the number of gridding points in the parameter space and the parameter variation rate limits in the system. The parametric study reveals a 7x7 grid ranging from Mach 7 to Mach 9 in velocity and from 70,000 feet to 90,000 feet in altitude, and a parameter variation rate limit of [.1 200]T is preferable for both the velocity tracking and altitude tracking cases with both the exible and rigid body assumptions. The resulting Hinfinity robust performances were gamma = 113:2146 for the exible body velocity tracking case, gamma = 83.6931 for the rigid body velocity tracking case, gamma = 107:2043 for the exible body altitude tracking case, and gamma = 97:7403 for the rigid body altitude tracking case. A linear analysis was then conducted on five different selected trim points from the Hinfinity LPV controller. The results of this analysis show that there is a larger difference in the response of the Hinfinity LPV controller and the Hinfinity controller. For the tracking task, the Hinfinity controller responds more quickly, and has a lower Hinfinity performance value. Next, the Hinfinity LPV controller was applied to the exible nonlinear plant model. The rigid body controllers were applied to the exible plant model to see if the exible nature of the vehicle could be treated as a perturbation to the system. Additionally, there were simulations run both with and without sensor noise and parametric uncertainty. The results of simulation show that the rigid body controller is able to successfully apply to the exible body model for the velocity tracking case, but is unable to stabilize the altitude tracking case. It was also seen that the system is able to track the command signal while minimizing the variations seen in the altitude for the velocity tracking case and in the velocity during the altitude tracking case. Additionally, there was no obvious effect of perturbations in the system on the tracking state or secondary regulation state. There were high frequency responses associated with the other perturbed states.

Meta-analyses of the Association of Sleep Apnea with Insulin Resistance, and the Effects of CPAP on HOMA-IR, Adiponectin, and Visceral Adipose Fat

PubMed Central

Iftikhar, Imran H.; Hoyos, Camilla M.; Phillips, Craig L.; Magalang, Ulysses J.

2015-01-01

Objective: We sought to conduct an updated meta-analysis of randomized controlled trials (RCTs) on the effect of continuous positive airway pressure (CPAP) on insulin resistance, as measured by homeostasis model assessment of insulin resistance (HOMA-IR), visceral abdominal fat (VAF), and adiponectin. Additionally, we performed a separate meta-analysis and meta-regression of studies on the association of insulin resistance and obstructive sleep apnea (OSA). Methods: All included studies were searched from PubMed (from conception to March 15, 2014). Data were pooled across all included RCTs as the mean difference in HOMA-IR and VAF, and as the standardized mean difference in the case of adiponectin analysis. From the included case-control studies, data on the difference of HOMA-IR between cases and controls were pooled across all studies, as the standardized mean difference (SMD). Results: There was a significant difference in HOMA-IR (−0.43 [95% CIs: −0.75 to −0.11], p = 0.008) between CPAP treated and non CPAP treated participants. However, there was no significant difference in VAF or adiponectin; (−47.93 [95% CI: −112.58 to 16.72], p = 0.14) and (−0.06 [95% CI: −0.28 to 0.15], p = 0.56), respectively. Meta-analysis of 16 case-control studies showed a pooled SMD in HOMA-IR of 0.51 (95% CI: 0.28 to 0.75), p ≤ 0.001, between cases and controls. Conclusions: The results of our meta-analyses show that CPAP has a favorable effect on insulin resistance. This effect is not associated with any significant changes in total adiponectin levels or amount of VAF. Our findings also confirm a significant association between OSA and insulin resistance. Citation: Iftikhar IH, Hoyos CM, Phillips CL, Magalang UJ. Meta-analyses of the association of sleep apnea with insulin resistance, and the effects of CPAP on HOMA-IR, adiponectin, and visceral adipose fat. J Clin Sleep Med 2015;11(4):475–485. PMID:25700870

The utility of caesarean myomectomy as a safe procedure: a retrospective analysis of 21 cases with review of literature.

PubMed

Kumar R, Ramesh; Patil, Manjula; Sa, Shruthi

2014-09-01

Myomectomy at the time of caesarean delivery has been discouraged because of the risk of intractable haemorrhage and increased postoperative morbidity. The aim of this study is to determine the safety and feasibility of caesarean myomectomy. A retrospective case control study done between June 2012 to May 2013 in a tertiary care teaching hospital in Karnataka, India which included 21 pregnant women with uterine fibroids who underwent myomectomy during caesarean section and were compared with 42 matched controls without uterine fibroids who had caesarean section alone during the same period. Primary outcome measures studied were incidence of haemorrhage and need for blood transfusion. Secondary outcome measures were duration of operation, length of hospital stay, postpartum fever and wound infection. Statistical analysis is done using IBMSPSS 20.0 software and students t-test. For calculation of incidence of haemorrhage Fisher's exact test is used. Mean age of the 21 cases was 31.81yrs and 47.62% were primigravida. Total 37 fibroids were removed. Subserosal were 30 cases(81.08%) while 1(2.07%) was submucous. 21(56.76%)fibroids were situated in fundal region and 3(8.11%) were in lower segment. Mean change in the haemoglobin from preoperative to postoperative period in the cases was 1.3gm/dl(±1.155mg/dl) and control was 1.05% (±.854mg/dl). Two of the cases(9.52%) required blood transfusion compared to none in control. None in either group required hysterectomy. Mean duration of surgery was 68.57min (±15.012min)and 51.55min (±9.595min) for controls which is statistically significant. This study shows that myomectomy during caesarean section is a safe procedure and is not associated with major intraoperative and postoperative complications.

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.

Case-control studies in cancer patients as a surveillance system of occupational exposure in the European Community. European Community Working Party.

PubMed Central

Rona, R J; Taub, N A; Rasmussen, S

1993-01-01

STUDY OBJECTIVE--The main aim was to detect known relationships between lung and blood cancers and various occupational exposures (using job titles as proxies) using a case-control design. The suitability of this system for routine surveillance could then be assessed. DESIGN--A case-control study was carried out in 1989. SETTING--Hospitals in eight European Community countries. SUBJECTS--Men aged 25 to 75 years with incident and prevalent cancer of the lung (190 cases), haematopoietic system (210 cases), or gastrointestinal tract (245 controls) were studied. MEASUREMENTS AND MAIN RESULTS--The crude estimate of the overall odds ratio exposure (OR) for relevant occupational exposure of lung cancer relative to gastrointestinal cancer was 1.20 (95% confidence interval (CI) 0.82, 1.77). In a logistic regression analysis adjusting for country, age at diagnosis, smoking, and alcohol consumption, the overall OR was not greatly changed. A significant interaction of occupational exposure and age at diagnosis showed that lung cancer patients diagnosed at a younger age had a higher OR than patients diagnosed at an older age. Thus, the overall, insignificant result may have been due to a low reliability of occupational history in older age or to a selective mechanism related to age. The overall OR for occupational exposure of cancer of the blood relative to gastrointestinal cancer was 0.88 (95% CI 0.60, 1.31). The logistic regression analysis did not alter these results. CONCLUSION--A surveillance based on a case-control design using job titles would not be sensitive enough to detect possible occupational risks. PMID:8228771

Validation of the trait anxiety scale for state-trait anxiety inventory in suicide victims and living controls of Chinese rural youths.

PubMed

Zhang, Jie; Gao, Qi

2012-01-01

This study evaluated the validation of STAI Trait-Anxiety Scale in suicide cases and community living controls in rural China. The participants were 392 suicides and 416 controls. Cronbach's Alpha was computed to evaluate the internal consistency. The Spearman Correlation Coefficient between Trait-Anxiety Scale and other instrument was calculated to evaluate the external validity, and the Exploratory Factor Analysis was used to evaluate the construct validity. The results showed the Cronbach's Alpha was .891 and .787 respectively in case and control groups. Most of the correlations between instruments were significant. We found 2 factors in cases and 3 factors in controls. We could cautiously infer that the Trait Anxiety Scale was an adequate tool to measure trait anxiety through proxy data in suicide victims and living controls in rural China.

Tularemia Outbreak Investigation in Kosovo: Case Control and Environmental Studies

PubMed Central

Dedushaj, Isuf; Gjini, Ardiana; Jorgensen, Tine Rikke; Cotter, Benvon; Lieftucht, Alfons; D’Ancona, Fortunato; Dennis, David T.; Kosoy, Michael A.; Mulliqi-Osmani, Gjyle; Grunow, Roland; Kalaveshi, Ariana; Gashi, Luljeta; Humolli, Isme

2002-01-01

A large outbreak of tularemia occurred in Kosovo in the early postwar period, 1999-2000. Epidemiologic and environmental investigations were conducted to identify sources of infection, modes of transmission, and household risk factors. Case and control status was verified by enzyme-linked immunosorbent assay, Western blot, and microagglutination assay. A total of 327 serologically confirmed cases of tularemia pharyngitis and cervical lymphadenitis were identified in 21 of 29 Kosovo municipalities. Matched analysis of 46 case households and 76 control households suggested that infection was transmitted through contaminated food or water and that the source of infection was rodents. Environmental circumstances in war-torn Kosovo led to epizootic rodent tularemia and its spread to resettled rural populations living under circumstances of substandard housing, hygiene, and sanitation. PMID:11749751

Association between age and high-risk human papilloma virus in Mexican oral cancer patients.

PubMed

González-Ramírez, I; Irigoyen-Camacho, M E; Ramírez-Amador, V; Lizano-Soberón, M; Carrillo-García, A; García-Carrancá, A; Sánchez-Pérez, Y; Méndez-Martínez, R; Granados-García, M; Ruíz-Godoy, Lm; García-Cuellar, Cm

2013-11-01

Studies reporting low prevalence of HPV in OSCC with declining age at presentation are increasing. The aim of this study was to determine the prevalence of HPV in a group of OSCC cases and controls in a Mexican population. The matched case-control study included 80 OSCC cases and 320 controls. HPV/DNA presence was evaluated through PCR amplification using three sets of consensus primers for the L1 gene. A conditional logistic regression analysis was carried out for the matched OSCC cases and controls. Interactions between risk factors and OCSS were tested in the construction process of the models. HPV prevalence was 5% in OSCC cases and 2.5% in controls. HPV-detected types were 16, 18 and 56. According to conditional logistics regression model, an association was detected between HR-HPV and OSCC. All HR-HPV-positive OSCC cases corresponded to young patients (<45 years), non-smokers and non-alcohol drinkers. The HR-HPV can be a contributing factor to oral carcinogenesis, especially in younger individuals without known risk factors such as tobacco and alcohol. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

A comparison of estimators from self-controlled case series, case-crossover design, and sequence symmetry analysis for pharmacoepidemiological studies.

PubMed

Takeuchi, Yoshinori; Shinozaki, Tomohiro; Matsuyama, Yutaka

2018-01-08

Despite the frequent use of self-controlled methods in pharmacoepidemiological studies, the factors that may bias the estimates from these methods have not been adequately compared in real-world settings. Here, we comparatively examined the impact of a time-varying confounder and its interactions with time-invariant confounders, time trends in exposures and events, restrictions, and misspecification of risk period durations on the estimators from three self-controlled methods. This study analyzed self-controlled case series (SCCS), case-crossover (CCO) design, and sequence symmetry analysis (SSA) using simulated and actual electronic medical records datasets. We evaluated the performance of the three self-controlled methods in simulated cohorts for the following scenarios: 1) time-invariant confounding with interactions between the confounders, 2) time-invariant and time-varying confounding without interactions, 3) time-invariant and time-varying confounding with interactions among the confounders, 4) time trends in exposures and events, 5) restricted follow-up time based on event occurrence, and 6) patient restriction based on event history. The sensitivity of the estimators to misspecified risk period durations was also evaluated. As a case study, we applied these methods to evaluate the risk of macrolides on liver injury using electronic medical records. In the simulation analysis, time-varying confounding produced bias in the SCCS and CCO design estimates, which aggravated in the presence of interactions between the time-invariant and time-varying confounders. The SCCS estimates were biased by time trends in both exposures and events. Erroneously short risk periods introduced bias to the CCO design estimate, whereas erroneously long risk periods introduced bias to the estimates of all three methods. Restricting the follow-up time led to severe bias in the SSA estimates. The SCCS estimates were sensitive to patient restriction. The case study showed that although macrolide use was significantly associated with increased liver injury occurrence in all methods, the value of the estimates varied. The estimations of the three self-controlled methods depended on various underlying assumptions, and the violation of these assumptions may cause non-negligible bias in the resulting estimates. Pharmacoepidemiologists should select the appropriate self-controlled method based on how well the relevant key assumptions are satisfied with respect to the available data.

Strategies and approaches to vector control in nine malaria-eliminating countries: a cross-case study analysis.

PubMed

Smith Gueye, Cara; Newby, Gretchen; Gosling, Roland D; Whittaker, Maxine A; Chandramohan, Daniel; Slutsker, Laurence; Tanner, Marcel

2016-01-04

There has been progress towards malaria elimination in the last decade. In response, WHO launched the Global Technical Strategy (GTS), in which vector surveillance and control play important roles. Country experiences in the Eliminating Malaria Case Study Series were reviewed to identify success factors on the road to elimination using a cross-case study analytic approach. Reports were included in the analysis if final English language draft reports or publications were available at the time of analysis (Bhutan, Cape Verde, Malaysia, Mauritius, Namibia, Philippines, Sri Lanka, Turkey, Turkmenistan). A conceptual framework for vector control in malaria elimination was developed, reviewed, formatted as a matrix, and case study data was extracted and entered into the matrix. A workshop was convened during which participants conducted reviews of the case studies and matrices and arrived at a consensus on the evidence and lessons. The framework was revised and a second round of data extraction, synthesis and summary of the case study reports was conducted. Countries implemented a range of vector control interventions. Most countries aligned with integrated vector management, however its impact was not well articulated. All programmes conducted entomological surveillance, but the response (i.e., stratification and targeting of interventions, outbreak forecasting and strategy) was limited or not described. Indoor residual spraying (IRS) was commonly used by countries. There were several examples of severe reductions or halting of IRS coverage and subsequent resurgence of malaria. Funding and operational constraints and poor implementation had roles. Bed nets were commonly used by most programmes; coverage and effectiveness were either not measured or not articulated. Larval control was an important intervention for several countries, preventing re-introduction, however coverage and impact on incidence were not described. Across all interventions, coverage indicators were incomparable, and the rationale for which tools were used and which were not used appeared to be a function of the availability of funding, operational issues and cost instead of evidence of effectiveness to reduce incidence. More work is required to fill gaps in programme guidance, clarify the best methods for choosing and targeting vector control interventions, and support to measure cost, cost-effectiveness and cost-benefit of vector surveillance and control interventions.

Patterns of Migration and Risks Associated with Leprosy among Migrants in Maranhão, Brazil

PubMed Central

Murto, Christine; Chammartin, Frédérique; Schwarz, Karolin; da Costa, Lea Marcia Melo; Kaplan, Charles; Heukelbach, Jorg

2013-01-01

Leprosy remains a public health problem in Brazil with new case incidence exceeding World Health Organization (WHO) goals in endemic clusters throughout the country. Migration can facilitate movement of disease between endemic and non-endemic areas, and has been considered a possible factor in continued leprosy incidence in Brazil. A study was conducted to investigate migration as a risk factor for leprosy. The study had three aims: (1) examine past five year migration as a risk factor for leprosy, (2) describe and compare geographic and temporal patterns of migration among past 5-year migrants with leprosy and a control group, and (3) examine social determinants of health associated with leprosy among past 5-year migrants. The study implemented a matched case-control design and analysis comparing individuals newly diagnosed with leprosy (n = 340) and a clinically unapparent control group (n = 340) without clinical signs of leprosy, matched for age, sex and location in four endemic municipalities in the state of Maranhão, northeastern Brazil. Fishers exact test was used to conduct bivariate analyses. A multivariate logistic regression analysis was employed to control for possible confounding variables. Eighty cases (23.5%) migrated 5-years prior to diagnosis, and 55 controls (16.2%) migrated 5-years prior to the corresponding case diagnosis. Past 5 year migration was found to be associated with leprosy (OR: 1.59; 95% CI 1.07–2.38; p = 0.02), and remained significantly associated with leprosy after controlling for leprosy contact in the family, household, and family/household contact. Poverty, as well as leprosy contact in the family, household and other leprosy contact, was associated with leprosy among past 5-year migrants in the bivariate analysis. Alcohol consumption was also associated with leprosy, a relevant risk factor in susceptibility to infection that should be explored in future research. Our findings provide insight into patterns of migration to localize focused control efforts in endemic areas with high population mobility. PMID:24040433

Does case misclassification threaten the validity of studies investigating the relationship between neck manipulation and vertebral artery dissection stroke? No.

PubMed

Murphy, Donald R; Schneider, Michael J; Perle, Stephen M; Bise, Christopher G; Timko, Michael; Haas, Mitchell

2016-01-01

The purported relationship between cervical manipulative therapy (CMT) and stroke related to vertebral artery dissection (VAD) has been debated for several decades. A large number of publications, from case reports to case-control studies, have investigated this relationship. A recent article suggested that case misclassification in the case-control studies on this topic resulted in biased odds ratios in those studies. Given its rarity, the best epidemiologic research design for investigating the relationship between CMT and VAD is the case-control study. The addition of a case-crossover aspect further strengthens the scientific rigor of such studies by reducing bias. The most recent studies investigating the relationship between CMT and VAD indicate that the relationship is not causal. In fact, a comparable relationship between vertebral artery-related stroke and visits to a primary care physician has been observed. The statistical association between visits to chiropractors and VAD can best be explained as resulting from a patient with early manifestation of VAD (neck pain with or without headache) seeking the services of a chiropractor for relief of this pain. Sometime after the visit the patient experiences VAD-related stroke that would have occurred regardless of the care received. This explanation has been challenged by a recent article putting forth the argument that case misclassification is likely to have biased the odds ratios of the case-control studies that have investigated the association between CMT and vertebral artery related stroke. The challenge particularly focused on one of the case-control studies, which had concluded that the association between CMT and vertebral artery related stroke was not causal. It was suggested by the authors of the recent article that misclassification led to an underestimation of risk. We argue that the information presented in that article does not support the authors' claim for a variety of reasons, including the fact that the assumptions upon which their analysis is based lack substantiation and the fact that any possible misclassification would not have changed the conclusion of the study in question. Current evidence does not support the notion that misclassification threatens the validity of recent case-control studies investigating the relationship between CMT and VAD. Hence, the recent re-analysis cannot refute the conclusion from previous studies that CMT is not a cause of VAD.

Glutathione S-transferase M1 polymorphism and endometriosis susceptibility: a meta-analysis.

PubMed

Li, H; Zhang, Y

2015-02-01

Many studies have investigated the association between glutathione S-transferase M1 (GSTM1) null genotype and the risk of endometriosis. However, the effect of the GSTM1 null genotype on endometriosis is still unclear because of apparent inconsistencies among those studies. A meta-analysis was performed to characterize the relationship more accurately. PubMed, Embase, and Web of Science were searched. To derive a more precise estimation of the relationship, a meta-analysis was performed. We estimated the summary odds ratio (OR) with a 95% confidence interval (95% CI) to assess the association. Up to 24 case-control studies with 2,684 endometriosis cases and 3,119 control cases were included into this meta-analysis. Meta-analysis of the 24 studies showed that GSTM1 null genotype was associated with the risk of endometriosis (random effects OR=1.66, 95% CI 1.23 to 2.24). In the subgroup analysis by ethnicity, increased risks were found for both Caucasians (OR=1.26, 95% CI 1.04-1.51) and Asians (OR=1.28, 95% CI 1.06-1.55). No evidence of publication bias was observed. In conclusion, this meta-analysis suggests that the GSTM1 null genotype increases the overall risk of endometriosis. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Risk of stroke in patients with patent foramen ovale: an updated meta-analysis of observational studies.

PubMed

Ma, Bing; Liu, Guangcong; Chen, Xin; Zhang, Jianming; Liu, Yiting; Shi, Jingpu

2014-01-01

Although patent foramen ovale (PFO) is considered to be associated with cryptogenic stroke (CS), there remains an ongoing disputation on this issue because of unstable results from randomized controlled trials. The aim of this study was to reassess the PFO effect on stroke through observational data. An electronic search of PubMed, Web of Science, and China National Knowledge Infrastructure (CNKI) were finished. Only case-control studies and cohort studies in Chinese or English were included in the analysis. Then random-effected meta-analysis models were performed to assess the association between PFO and stroke. Twelve case-control studies and 6 cohort studies were eligible. Case-control studies showed strong association between PFO and CS (odds ratio [OR]: 2.94, 95% confidence interval [CI]: 2.06, 4.20; P < .001), but cohort studies failed to demonstrate a significant association (hazard ratio [HR]: 1.28, 95% CI: .91, 1.80; P = .155). Subgroup analysis revealed that the pooled OR decreased significantly when the region was limited to the United States (OR: 1.52, 95% CI: 1.00, 2.32; P = .083). OR of studies that adjusted major confounders was 1.74 (95% CI: 1.22, 2.47; P = .119) and high-quality studies was 1.68 (95% CI: 1.14, 2.47; P = .072). For cohort studies, a weak statistical association was observed in using transesophageal echocardiography (TEE) studies (HR: 1.45, 95% CI: 1.06, 2.01; P = .138) and follow-up years less than 4 years' studies (HR: 1.45, 95% CI: 1.00, 2.09; P = .064). Although case-control studies still show a positive effect of PFO on stroke, the results of cohort challenged the credibility. Further trial data are needed to confirm the effect of PFO on stroke. Copyright © 2014 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Association of HLA-B*5801 allele and allopurinol-induced stevens johnson syndrome and toxic epidermal necrolysis: a systematic review and meta-analysis

PubMed Central

2011-01-01

Background Despite some studies suggesting a possible association between human leukocyte antigen, HLA-B*5801 and allopurinol induced Stevens-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN), the evidence of association and its magnitude remain inconclusive. This study aims to systematically review and meta-analyze the association between HLA-B*5801 allele and allopurinol-induced SJS/TEN. Methods A comprehensive search was performed in databases including MEDLINE, Pre-MEDLINE, Cochrane Library, EMBASE, International Pharmaceutical Abstracts (IPA), CINAHL, PsychInfo, the WHO International, Clinical Trial Registry, and ClinicalTrial.gov from their inceptions to June 2011. Only studies investigating association between HLA-B*5801 with allopurinol-induced SJS/TEN were included. All studies were extracted by two independent authors. The primary analysis was the carrier frequency of HLA-B*5801 comparison between allopurinol-induced SJS/TEN cases and each comparative group. The pooled odds ratios were calculated using a random effect model. Results A total of 4 studies with 55 SJS/TEN cases and 678 matched-controls (allopurinol-tolerant control) was identified, while 5 studies with 69 SJS/TEN cases and 3378 population-controls (general population) were found. SJS/TEN cases were found to be significantly associated with HLA-B*5801 allele in both groups of studies with matched-control (OR 96.60, 95%CI 24.49-381.00, p < 0.001) and population-control (OR 79.28, 95%CI 41.51-151.35, p < 0.001). Subgroup analysis for Asian and Non-Asian population yielded similar findings. Conclusion We found a strong and significant association between HLA-B*5801 and allopurinol-induced SJS/TEN. Therefore, HLA-B*5801 allele screening may be considered in patients who will be treated with allopurinol. PMID:21906289

Periodontitis and risk of psoriasis: a systematic review and meta-analysis.

PubMed

Ungprasert, P; Wijarnpreecha, K; Wetter, D A

2017-05-01

The association between periodontitis and systemic diseases has been increasingly recognized. However, the data on the association between periodontitis and psoriasis are still limited. To summarize all available data on the association between periodontitis and the risk of psoriasis. Two investigators independently searched published studies indexed in MEDLINE and EMBASE databases from inception to July 2016 using a search strategy that included terms for psoriasis and periodontitis. Studies were included if the following criteria were met: (i) case-control or cohort study comparing the risk of psoriasis in subjects with and without periodontitis; (ii) subjects without periodontitis were used as comparators in cohort studies while participants without psoriasis were used as controls in case-control studies; and (iii) effect estimates and 95% confidence intervals (CI) were provided. Point estimates and standard errors from each study were extracted and combined together using the generic inverse variance technique described by DerSimonian and Laird. Two cohort studies and three case-control studies met the inclusion criteria and were included in the meta-analysis. The pooled risk ratio of psoriasis in patients with periodontitis versus comparators was 1.55 (95% CI, 1.35-1.77). The statistical heterogeneity was insignificant with an I 2 of 18%. Subgroup analysis according to study design revealed a significantly higher risk among patients with periodontitis with a pooled RR of 1.50 (95% CI, 1.37-1.64) for cohort studies and a pooled RR of 2.33 (95% CI, 1.51-3.60) for case-control studies. Patients with periodontitis have a significantly elevated risk of psoriasis. © 2016 European Academy of Dermatology and Venereology.

Epidemiology and risk factors for infections due to AmpC β-lactamase-producing Escherichia coli.

PubMed

Pascual, Vanesa; Ortiz, Gabriel; Simó, Maria; Alonso, Noemí; Garcia, Maria Consol; Xercavins, Mariona; Rivera, Alba; Morera, Maria Antonia; Miró, Elisenda; Espejo, Elena; Navarro, Ferran; Gurguí, Mercè; Pérez, Josefa; Rodríguez-Carballeira, Mónica; Garau, Javier; Calbo, Esther

2015-03-01

To describe the prevalence and risk factors for infection due to AmpC β-lactamase-producing Escherichia coli (AmpC-EC). For the prevalence study, all clinical isolates of E. coli with reduced susceptibility to third-generation cephalosporins were prospectively included from June 2010 to November 2011. For risk factor analysis, a case-control study was conducted. Cases were patients with an infection due to AmpC-EC. Controls were patients infected with cephalosporin-susceptible E. coli, matched 1 : 2. Detection of blaAmpC genes was done with a multiplex AmpC-PCR, and hyperproduction of E. coli chromosomal blaAmpC by quantitative RT-PCR. Alteration of the blaAmpC promoter was studied by PCR and sequencing. We identified 243 (1.1%) AmpC-EC strains out of 21 563 clinical isolates. Three cases with strains carrying ESBLs, 18 strains that were considered due to colonization and 8 cases lost to clinical follow-up were excluded. Finally, 214 cases were included in the analysis. Ninety-one cases (42.5%) and 269 (62.8%) controls were strictly community acquired (P < 0.001). Thirty-five (16.3%) cases and 186 controls (43.5%) did not have any identifiable risk factor (P < 0.001). Among cases, 158 (73.8%) were found to harbour an acquired AmpC (73.4% CMY-2). Previous use of fluoroquinolones [OR 2.6 (95% CI 1.12-3.36); P = 0.008] was independently associated with AmpC-EC in the multivariate analysis. Prevalence of AmpC in E. coli remains low in our area. Plasmid acquisition (CMY type) represents the main mechanism of AmpC production. A high proportion of community-acquired isolates and patients with no identifiable risk factors were found. Previous use of fluoroquinolones was identified as a risk factor. © The Author 2014. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

International genome-wide meta-analysis identifies new primary biliary cirrhosis risk loci and targetable pathogenic pathways.

PubMed

Cordell, Heather J; Han, Younghun; Mells, George F; Li, Yafang; Hirschfield, Gideon M; Greene, Casey S; Xie, Gang; Juran, Brian D; Zhu, Dakai; Qian, David C; Floyd, James A B; Morley, Katherine I; Prati, Daniele; Lleo, Ana; Cusi, Daniele; Gershwin, M Eric; Anderson, Carl A; Lazaridis, Konstantinos N; Invernizzi, Pietro; Seldin, Michael F; Sandford, Richard N; Amos, Christopher I; Siminovitch, Katherine A

2015-09-22

Primary biliary cirrhosis (PBC) is a classical autoimmune liver disease for which effective immunomodulatory therapy is lacking. Here we perform meta-analyses of discovery data sets from genome-wide association studies of European subjects (n=2,764 cases and 10,475 controls) followed by validation genotyping in an independent cohort (n=3,716 cases and 4,261 controls). We discover and validate six previously unknown risk loci for PBC (Pcombined<5 × 10(-8)) and used pathway analysis to identify JAK-STAT/IL12/IL27 signalling and cytokine-cytokine pathways, for which relevant therapies exist.

A genome-wide association meta-analysis identifies new childhood obesity loci

PubMed Central

Bradfield, Jonathan P.; Taal, H. Rob; Timpson, Nicholas J.; Scherag, André; Lecoeur, Cecile; Warrington, Nicole M.; Hypponen, Elina; Holst, Claus; Valcarcel, Beatriz; Thiering, Elisabeth; Salem, Rany M.; Schumacher, Fredrick R.; Cousminer, Diana L.; Sleiman, Patrick M.A.; Zhao, Jianhua; Berkowitz, Robert I.; Vimaleswaran, Karani S.; Jarick, Ivonne; Pennell, Craig E.; Evans, David M.; St. Pourcain, Beate; Berry, Diane J.; Mook-Kanamori, Dennis O; Hofman, Albert; Rivadeinera, Fernando; Uitterlinden, André G.; van Duijn, Cornelia M.; van der Valk, Ralf J.P.; de Jongste, Johan C.; Postma, Dirkje S.; Boomsma, Dorret I.; Gauderman, William J.; Hassanein, Mohamed T.; Lindgren, Cecilia M.; Mägi, Reedik; Boreham, Colin A.G.; Neville, Charlotte E.; Moreno, Luis A.; Elliott, Paul; Pouta, Anneli; Hartikainen, Anna-Liisa; Li, Mingyao; Raitakari, Olli; Lehtimäki, Terho; Eriksson, Johan G.; Palotie, Aarno; Dallongeville, Jean; Das, Shikta; Deloukas, Panos; McMahon, George; Ring, Susan M.; Kemp, John P.; Buxton, Jessica L.; Blakemore, Alexandra I.F.; Bustamante, Mariona; Guxens, Mònica; Hirschhorn, Joel N.; Gillman, Matthew W.; Kreiner-Møller, Eskil; Bisgaard, Hans; Gilliland, Frank D.; Heinrich, Joachim; Wheeler, Eleanor; Barroso, Inês; O'Rahilly, Stephen; Meirhaeghe, Aline; Sørensen, Thorkild I.A.; Power, Chris; Palmer, Lyle J.; Hinney, Anke; Widen, Elisabeth; Farooqi, I. Sadaf; McCarthy, Mark I.; Froguel, Philippe; Meyre, David; Hebebrand, Johannes; Jarvelin, Marjo-Riitta; Jaddoe, Vincent W.V.; Smith, George Davey; Hakonarson, Hakon; Grant, Struan F.A.

2012-01-01

Multiple genetic variants have been associated with adult obesity and a few with severe obesity in childhood; however, less progress has been made to establish genetic influences on common early-onset obesity. We performed a North American-Australian-European collaborative meta-analysis of fourteen studies consisting of 5,530 cases (≥95th percentile of body mass index (BMI)) and 8,318 controls (<50th percentile of BMI) of European ancestry. Taking forward the eight novel signals yielding association with P < 5×10−6 in to nine independent datasets (n = 2,818 cases and 4,083 controls) we observed two loci that yielded a genome wide significant combined P-value, namely near OLFM4 on 13q14 (rs9568856; P=1.82×10−9; OR=1.22) and within HOXB5 on 17q21 (rs9299; P=3.54×10−9; OR=1.14). Both loci continued to show association when including two extreme childhood obesity cohorts (n = 2,214 cases and 2,674 controls). Finally, these two loci yielded directionally consistent associations in the GIANT meta-analysis of adult BMI1. PMID:22484627

Association between the ghrelin Leu72Met polymorphism and type 2 diabetes risk: a meta-analysis.

PubMed

Liao, Ning; Xie, Zi-Kang; Huang, Jian; Xie, Zheng-Fu

2013-04-01

Data on the association between the ghrelin Leu72Met polymorphism and type 2 diabetes are conflicting. A meta-analysis was performed on this topic. We searched for case-control studies using electronic databases (Medline and PubMed) and reference lists of studies. Odds ratios (OR) and 95% confidence intervals (CI) assuming dominant, recessive and homozygote comparison genetic models were calculated. Six case-control studies involving a total of 3417 cases and 3081 controls were included in this meta-analysis. No association was found between the ghrelin Leu72Met polymorphism and type 2 diabetes risk in the overall population in dominant, recessive and homozygote comparison models. However, in subgroup analyses stratified by ethnicity, we found that the risk for type 2 diabetes was decreased in subjects with Met72+ genotypes in Caucasians (OR=0.79, 95% CI: 0.64-0.98, P(z)=0.030). The ghrelin Leu72Met polymorphism was protective against type 2 diabetes in Caucasians. Future studies performed in larger sample size are needed to allow a more definitive conclusion. Copyright © 2012 Elsevier B.V. All rights reserved.

Interaction between Maternal and Paternal SHMT1 C1420T Predisposes to Neural Tube Defects in the Fetus: Evidence from Case-Control and Family-Based Triad Approaches.

PubMed

K Rebekah, Prasoona; Tella, Sunitha; Buragadda, Srinadh; Tiruvatturu, Muni Kumari; Akka, Jyothy

2017-04-14

Neural tube defects (NTDs) are caused by the failure of neural tube formation which occurs during early embryonic development. NTDs are the most severe and leading cause of fetal mortality. Serine hydroxymethyl transferase (SHMT1) provides one-carbon units necessary for embryogenesis and defects in one-carbon production result in specific pathological conditions during pregnancy. The present study is aimed to evaluate the association of SHMT1 C1420T with NTD risk in the fetus using fetal, maternal and paternal groups by applying both case-control and family-based triad approaches. A total of 924 subjects including 124 NTD case-parent trios (n = 124 × 3 = 372) and 184 healthy control-parent trios (n = 184 × 3 = 552) from Telangana State, South India were analyzed. DNA from umbilical cord tissues and parental blood samples were extracted, and genotyped by polymerase chain reaction-restriction fragment length polymorphism. Statistical analysis used were SPSS, parent-of-origin effect (POE) analysis. Case-control study design demonstrated fetuses with homozygous variant genotype (TT) to be at risk toward spina bifida subtype (p = 0.022). Among parents, fathers with TT genotype were associated with anencephaly (p = 0.018) and spina bifida subtypes (p = 0.027) in the offspring. Of interest, maternal-paternal-offspring genotype incompatibility revealed maternal CT genotype in combination with paternal TT genotype increased risk for NTDs in the fetus (CTxTT = TT; p = 0.021). Family-based parent-of-origin effect linkage analysis revealed significant maternal over-transmission of variant allele to NTD fetuses (p < 0.01). The present study, using both case-control and family-based triad approach is the first report to demonstrate parental association of SHMT1 C1420T variant in conferring NTD risk in the fetus. Birth Defects Research, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Interaction between Maternal and Paternal SHMT1 C1420T Predisposes to Neural Tube Defects in the Fetus: Evidence from Case-Control and Family-Based Triad Approaches.

PubMed

K Rebekah, Prasoona; Tella, Sunitha; Buragadda, Srinadh; Tiruvatturu, Muni Kumari; Akka, Jyothy

2017-07-17

Neural tube defects (NTDs) are caused by the failure of neural tube formation which occurs during early embryonic development. NTDs are the most severe and leading cause of fetal mortality. Serine hydroxymethyl transferase (SHMT1) provides one-carbon units necessary for embryogenesis and defects in one-carbon production result in specific pathological conditions during pregnancy. The present study is aimed to evaluate the association of SHMT1 C1420T with NTD risk in the fetus using fetal, maternal and paternal groups by applying both case-control and family-based triad approaches. A total of 924 subjects including 124 NTD case-parent trios (n = 124 × 3 = 372) and 184 healthy control-parent trios (n = 184 × 3 = 552) from Telangana State, South India were analyzed. DNA from umbilical cord tissues and parental blood samples were extracted, and genotyped by polymerase chain reaction-restriction fragment length polymorphism. Statistical analysis used were SPSS, parent-of-origin effect (POE) analysis. Case-control study design demonstrated fetuses with homozygous variant genotype (TT) to be at risk toward spina bifida subtype (p = 0.022). Among parents, fathers with TT genotype were associated with anencephaly (p = 0.018) and spina bifida subtypes (p = 0.027) in the offspring. Of interest, maternal-paternal-offspring genotype incompatibility revealed maternal CT genotype in combination with paternal TT genotype increased risk for NTDs in the fetus (CTxTT = TT; p = 0.021). Family-based parent-of-origin effect linkage analysis revealed significant maternal over-transmission of variant allele to NTD fetuses (p < 0.01). The present study, using both case-control and family-based triad approach is the first report to demonstrate parental association of SHMT1 C1420T variant in conferring NTD risk in the fetus. Birth Defects Research 109:1020-1029, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Evidence of Recessive Alzheimer Disease Loci in a Caribbean Hispanic Data Set

PubMed Central

Ghani, Mahdi; Sato, Christine; Lee, Joseph H.; Reitz, Christiane; Moreno, Danielle; Mayeux, Richard; St George-Hyslop, Peter; Rogaeva, Ekaterina

2014-01-01

IMPORTANCE The search for novel Alzheimer disease (AD) genes or pathologic mutations within known AD loci is ongoing. The development of array technologies has helped to identify rare recessive mutations among long runs of homozygosity (ROHs), in which both parental alleles are identical. Caribbean Hispanics are known to have an elevated risk for AD and tend to have large families with evidence of inbreeding. OBJECTIVE To test the hypothesis that the late-onset AD in a Caribbean Hispanic population might be explained in part by the homozygosity of unknown loci that could harbor recessive AD risk haplotypes or pathologic mutations. DESIGN We used genome-wide array data to identify ROHs (>1 megabase) and conducted global burden and locus-specific ROH analyses. SETTING A whole-genome case-control ROH study. PARTICIPANTS A Caribbean Hispanic data set of 547 unrelated cases (48.8% with familial AD) and 542 controls collected from a population known to have a 3-fold higher risk of AD vs non-Hispanics in the same community. Based on a Structure program analysis, our data set consisted of African Hispanic (207 cases and 192 controls) and European Hispanic (329 cases and 326 controls) participants. EXPOSURE Alzheimer disease risk genes. MAIN OUTCOMES AND MEASURES We calculated the total and mean lengths of the ROHs per sample. Global burden measurements among autosomal chromosomes were investigated in cases vs controls. Pools of overlapping ROH segments (consensus regions) were identified, and the case to control ratio was calculated for each consensus region. We formulated the tested hypothesis before data collection. RESULTS In total, we identified 17 137 autosomal regions with ROHs. The mean length of the ROH per person was significantly greater in cases vs controls (P = .0039), and this association was stronger with familial AD (P = .0005). Among the European Hispanics, a consensus region at the EXOC4 locus was significantly associated with AD even after correction for multiple testing (empirical P value 1 [EMP1], .0001; EMP2, .002; 21 AD cases vs 2 controls). Among the African Hispanic subset, the most significant but nominal association was observed for CTNNA3, a well-known AD gene candidate (EMP1, .002; 10 AD cases vs 0 controls). CONCLUSIONS AND RELEVANCE Our results show that ROHs could significantly contribute to the etiology of AD. Future studies would require the analysis of larger, relatively inbred data sets that might reveal novel recessive AD genes. The next step is to conduct sequencing of top significant loci in a subset of samples with overlapping ROHs. PMID:23978990

Nutrient intake and gastric cancer risk: a case-control study in Spain.

PubMed

Ramón, J M; Serra-Majem, L; Cerdó, C; Oromí, J

1993-12-01

A case-control study of dietary factors and gastric cancer was conducted between September 1986 and March 1989 in the Barcelona metropolitan area, Spain. In all 117 cases with histologically confirmed diagnosis of gastric adenocarcinoma were matched on sex, age and possession of a telephone to 234 population controls. Of the controls 188 (80.3%) were selected by random digit telephone dialing and 46 (19.7%) by neighbourhood of residence. Information about frequency and amount of consumption of 89 alimentary items was gathered by questionnaire, and cases and controls were interviewed in their homes by trained interviewers. The gastric cancer risk decreased in proportion to vitamin C intake. In multivariate analysis adjusting for major covariables, energy and vitamin A intake, the estimated odds ratio (OR) for the upper quartile of vitamin C intake was 0.3 (95% confidence interval [CI]: 0.1-0.8). After adjustment for major covariables, calories and vitamin C intake, vitamin A did not show significant association with the gastric cancer risk. Our findings are consistent with previous case-control studies and with the hypothesis that vitamin C may inhibit the intragastric nitrosation process.

Epidemiology of measles in Southwest Nigeria: an analysis of measles case-based surveillance data from 2007 to 2012.

PubMed

Fatiregun, Akinola A; Adebowale, Ayodeji S; Fagbamigbe, Adeniyi F

2014-03-01

In Nigeria, a system of measles case-based surveillance with laboratory confirmation of suspected cases was introduced in 2005 as one of the strategies for the control of measles morbidity and mortality. In this report, we provide an epidemiological distribution of confirmed cases of measles reported from the southwest of the country between 2007 and 2012, and predict the expected number of cases for the ensuing years. A descriptive analysis of persons and place and time of confirmed measles cases (laboratory and epidemiological link) reported in the case-based surveillance data was carried out. Using an additive time series model, we predicted the expected number of cases to the year 2015, assuming that current interventional efforts were sustained. From the 10 187 suspected cases investigated during the time period, 1631 (16.0%) cases of measles were confirmed. The annual incidence rose from <1 case per million in 2007 to 23 cases per million in 2011. Cases were confirmed from all six states within the zone and most (97.4%) were in individuals aged less than 20 years. Seasonal variation existed with peaks of infection in the first and second quarters of the year. There was an increasing trend in the number of expected cases based on projections. Case-based surveillance provided an insight into understanding the epidemiology of measles infection in Southwest Nigeria. There is a need to work out alternate strategies for control of measles and to strengthen the surveillance system.

Apolipoprotein A5 and apolipoprotein C3 single nucleotide polymorphisms are correlated with an increased risk of coronary heart disease: a case-control and meta-analysis study.

PubMed

Yang, Guang; Lei, Ming-Ming; Yu, Chun-Lei; Liu, Xiao-Xiao; An, Zhe; Song, Chun-Li

2015-09-19

Triglycerides (TGs) are proatherogenic lipoproteins involving the risk of coronary heart disease (CHD), while apolipoprotein A5 (APOA5) and apolipoprotein C3 (APOC3) are main lipoproteins composing TG-rich lipoproteins. In this study, we aim to explore the correlation of CHD with APOA5 -1131 T > C and APOC3 -455 T > C single nucleotide polymorphisms (SNPs). A sum of 210 CHD patients, hospitalized between Jan. 2013 and Mar. 2015 at China-Japan Union Hospital, Jilin University, were selected as our case group and 223 healthy individuals who had physical examination at same hospital at the same period were selected as control group. The frequency distribution of genotypes of APOA5 -1131 T > C and APOC3 -455 T > C SNPs were measured by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The Stata 12.0 software was utilized for statistical analyses. There was no significant difference on age and sex between case and control group (P > 0.05). History of smoking, drinking, hypertension and diabetes mellitus, body mass index and levels of TG and fasting blood sugar in case group were shown to be higher than control group (P < 0.05), while levels of total cholesterol, high-density lipoprotein cholesterol and low-density lipoprotein cholesterol in case group were lower than control group (P < 0.05). Both CC and TC' + CC frequencies of APOA5 -1131 T > C and APOC3 -455 T > C in case group were higher compared to control group (both P < 0.05). Additionally, T allele frequencies of the two SNPs in case group were lower than control group, while C allele in case group has higher frequencies compared to control group (both P < 0.05). The results of meta-analysis under allele and dominant models showed that APOA5 -1131 T > C and APOC3 -455 T > C SNPs are likely to increase the risk of CHD (both P < 0.05). APOA5 -1131 T > C and APOC3 -455 T > C SNPs may play potent roles in the development and progression of CHD.

Prenatal folic acid use associated with decreased risk of myelomeningocele: A case-control study offers further support for folic acid fortification in Bangladesh.

PubMed

Kancherla, Vijaya; Ibne Hasan, Md Omar Sharif; Hamid, Rezina; Paul, Ligi; Selhub, Jacob; Oakley, Godfrey; Quamruzzaman, Quazi; Mazumdar, Maitreyi

2017-01-01

Neural tube defects contribute to severe morbidity and mortality in children and adults; however, they are largely preventable through maternal intake of folic acid before and during early pregnancy. We examined the association between maternal prenatal folic acid supplement intake and risk of myelomeningocele (a severe and common type of neural tube defect) in the offspring. We performed secondary analysis using data from a case-control study conducted at Dhaka Community Hospital, Bangladesh between April and November of 2013. Cases and controls included children with and without myelomeningocele, respectively, and their mothers. Cases were identified from local hospitals and rural health clinics served by Dhaka Community Hospital. Controls were selected from pregnancy registries located in the same region as the cases, and matched (1:1) to cases by age and sex. Myelomeningocele in the offspring was confirmed by a pediatrician with expertise in classifying neural tube defects. Maternal prenatal folic acid supplement intake was the main exposure of interest. We estimated crude and adjusted odds ratios (OR) and 95% confidence intervals (CI) using conditional logistic regression analysis. There were 53 pairs of matched cases and controls in our study. Overall, 51% of case mothers reported using folic acid supplements during pregnancy compared to 72% of control mothers (p = 0.03). Median plasma folate concentrations at the time of study visit were 2.79 ng/mL and 2.86 ng/mL among case and control mothers, respectively (p = 0.85). Maternal prenatal folic acid use significantly decreased the odds of myelomeningocele in the offspring (unadjusted OR = 0.42, 95% CI = 0.18-0.96). The association was slightly attenuated after adjusting for maternal age at the time of pregnancy (adjusted OR = 0.43, 95% CI = 0.18-1.02). Our study confirms the protective association between maternal prenatal folic acid supplement use and myelomeningocele among children born in Bangladesh. Our findings point to an overall low folic acid supplement use and low plasma folate concentrations among women of reproductive age in Bangladesh. Mandatory fortification of staple foods with folic acid can address low folate status among women of child-bearing age, and prevent child morbidity and mortality associated with myelomeningocele in Bangladesh.

Lung Cancer Risk Among Hairdressers: A Pooled Analysis of Case-Control Studies Conducted Between 1985 and 2010

PubMed Central

Olsson, Ann C.; Xu, Yiwen; Schüz, Joachim; Vlaanderen, Jelle; Kromhout, Hans; Vermeulen, Roel; Peters, Susan; Stücker, Isabelle; Guida, Florence; Brüske, Irene; Wichmann, Heinz-Erich; Consonni, Dario; Landi, Maria Teresa; Caporaso, Neil; Tse, Lap Ah; Yu, Ignatius Tak-sun; Siemiatycki, Jack; Richardson, Lesley; Mirabelli, Dario; Richiardi, Lorenzo; Simonato, Lorenzo; Gustavsson, Per; Plato, Nils; Jöckel, Karl-Heinz; Ahrens, Wolfgang; Pohlabeln, Hermann; Tardón, Adonina; Zaridze, David; Marcus, Michael W.; ‘t Mannetje, Andrea; Pearce, Neil; McLaughlin, John; Demers, Paul; Szeszenia-Dabrowska, Neonila; Lissowska, Jolanta; Rudnai, Peter; Fabianova, Eleonora; Dumitru, Rodica Stanescu; Bencko, Vladimir; Foretova, Lenka; Janout, Vladimir; Boffetta, Paolo; Fortes, Cristina; Bueno-de-Mesquita, Bas; Kendzia, Benjamin; Behrens, Thomas; Pesch, Beate; Brüning, Thomas; Straif, Kurt

2013-01-01

Increased lung cancer risks among hairdressers were observed in large registry-based cohort studies from Scandinavia, but these studies could not adjust for smoking. Our objective was to evaluate the lung cancer risk among hairdressers while adjusting for smoking and other confounders in a pooled database of 16 case-control studies conducted in Europe, Canada, China, and New Zealand between 1985 and 2010 (the Pooled Analysis of Case-Control Studies on the Joint Effects of Occupational Carcinogens in the Development of Lung Cancer). Lifetime occupational and smoking information was collected through interviews with 19,369 cases of lung cancer and 23,674 matched population or hospital controls. Overall, 170 cases and 167 controls had ever worked as hairdresser or barber. The odds ratios for lung cancer in women were 1.65 (95% confidence interval (CI): 1.16, 2.35) without adjustment for smoking and 1.12 (95% CI: 0.75, 1.68) with adjustment for smoking; however, women employed before 1954 also experienced an increased lung cancer risk after adjustment for smoking (odds ratio = 2.66, 95% CI: 1.09, 6.47). The odds ratios in male hairdressers/barbers were generally not elevated, except for an increased odds ratio for adenocarcinoma in long-term barbers (odds ratio = 2.20, 95% CI: 1.02, 4.77). Our results suggest that the increased lung cancer risks among hairdressers are due to their smoking behavior; single elevated risk estimates should be interpreted with caution and need replication in other studies. PMID:24068200

Exploring single nucleotide polymorphisms previously related to obesity and metabolic traits in pediatric-onset type 2 diabetes.

PubMed

Miranda-Lora, América Liliana; Cruz, Miguel; Aguirre-Hernández, Jesús; Molina-Díaz, Mario; Gutiérrez, Jorge; Flores-Huerta, Samuel; Klünder-Klünder, Miguel

2017-07-01

To evaluate the association of 64 obesity-related polymorphisms with pediatric-onset type 2 diabetes and other glucose- and insulin-related traits in Mexican children. Case-control and case-sibling designs were followed. We studied 99 patients with pediatric-onset type 2 diabetes, their siblings (n = 101) without diabetes, 83 unrelated pediatric controls and 137 adult controls. Genotypes were determined for 64 single nucleotide polymorphisms, and a possible association was examined between those genotypes and type 2 diabetes and other quantitative traits, after adjusting for age, sex and body mass index. In the case-pediatric control and case-adult control analyses, five polymorphisms were associated with increased likelihood of pediatric-onset type 2 diabetes; only one of these polymorphisms (CADM2/rs1307880) also showed a consistent effect in the case-sibling analysis. The associations in the combined analysis were as follows: ADORA1/rs903361 (OR 1.9, 95% CI 1.2; 3.0); CADM2/rs13078807 (OR 2.2, 95% CI 1.2; 4.0); GNPDA2/rs10938397 (OR 2.2, 95% CI 1.4; 3.7); VEGFA/rs6905288 (OR 1.4, 95% CI 1.1; 2.1) and FTO/rs9939609 (OR 1.8, 95% CI 1.0; 3.2). We also identified 16 polymorphisms nominally associated with quantitative traits in participants without diabetes. ADORA/rs903361, CADM2/rs13078807, GNPDA2/rs10938397, VEGFA/rs6905288 and FTO/rs9939609 are associated with an increased risk of pediatric-onset type 2 diabetes in the Mexican population.

Risk factors for hospital acquisition of trimethoprim-sulfamethoxazole resistant Stenotrophomonas maltophilia in adults: A matched case-control study.

PubMed

Wang, Ching-Hsun; Lin, Jung-Chung; Chang, Feng-Yee; Yu, Ching-Mei; Lin, Wei-San; Yeh, Kuo-Ming

2017-10-01

The emergence of trimethoprim-sulfamethoxazole resistant Stenotrophomonas maltophilia (TSRSM) represents a serious threat to patients. The aim of current study was to identify risk factors associated with hospital-acquired TSRSM occurrence in adult inpatients. We conducted a matched case-control study in Tri-Service General Hospital, Taipei, Taiwan. From January 2014 through June 2015, case patients with TSRSM and control patients with trimethoprim-sulfamethoxazole susceptible S. maltophilia (TSSSM) during hospitalization were identified. Control patients were matched with TSRSM cases for age (within five years), sex, and site of isolation at a ratio of 1:1. A total of 266 patients were included in our study (133 cases and 133 matched controls). Bivariable analysis showed that previous exposure to fluoroquinolone [odds ratio (OR), 2.693; 95% confidence interval (CI, 1.492-5.884; p = 0.002)], length of intensive care unit stay (OR, 1.015 per day; 95% CI, 1.001-1.030; p = 0.041), and length of hospital stay (OR, 1.012 per day; 95% CI, 1.002-1.023; p = 0.018) prior to S. maltophilia isolation were associated with TSRSM occurrence. A multivariable analysis showed that previous exposure to fluoroquinolone (OR, 3.158; 95% CI, 1.551-6.430; p = 0.002) was an independent risk factor for TSRSM occurrence after adjustment. Previous fluoroquinolone use was an independent risk factor for hospital-acquired TSRSM occurrence in adult inpatients, suggesting that judicious administration of fluoroquinolone may be important for limiting TSRSM occurrence. Copyright © 2017. Published by Elsevier B.V.

Plasma Homocysteine, Serum Folic Acid, Serum Vitamin B12, Serum Vitamin B6, MTHFR, and Risk of Normal-Tension Glaucoma.

PubMed

Li, Jinmiao; Xu, Fan; Zeng, Rui; Gong, Haijun; Lan, Yuqing

2016-02-01

This meta-analysis aims to comprehensively evaluate the association between total homocysteine (tHcy) levels, serum folic acid, vitamin B12, vitamin B6 levels, methylenetetrahydrofolate reductase (MTHFR) C677T genotype, and risk of normal-tension glaucoma (NTG). A systematic search of the EMBASE and PubMed databases was performed to evaluate plasma tHcy levels, serum folic acid, B vitamins' mean difference, and odds ratios of MTHFR C677T genotype between cases and controls. A total of 7 studies including 458 cases and 555 controls meeting the inclusion criteria were involved in this meta-analysis. There were 4 studies for tHcy (149 cases and 148 controls), 2 studies for vitamin B6, vitamin B12, and folate (90 cases and 82 controls), and 4 studies for MTHFR (343 cases and 449 controls). Overall, the mean plasma tHcy levels, serum folic acids, vitamin B12, and vitamin B6 levels were 1.16 μmol/L [95% confidence interval (CI), -0.13, 2.45], -0.62 μmol/L (95% CI, -1.98, 0.74), 5.81 μmol/L (95% CI, -3.53, 15.14), and -16.79 μmol/L (95% CI, -86.09, 52.51). MTHFR TT genotype was found to be unrelated to NTG risk (odds ratio=1.08; 95% CI, 0.69, 1.69). NTG is not associated with elevated plasma tHcy, serum folic acid, serum vitamin B12, serum vitamin B6, and MTHFR C677T genotype.

Characterizing mammographic images by using generic texture features

PubMed Central

2012-01-01

Introduction Although mammographic density is an established risk factor for breast cancer, its use is limited in clinical practice because of a lack of automated and standardized measurement methods. The aims of this study were to evaluate a variety of automated texture features in mammograms as risk factors for breast cancer and to compare them with the percentage mammographic density (PMD) by using a case-control study design. Methods A case-control study including 864 cases and 418 controls was analyzed automatically. Four hundred seventy features were explored as possible risk factors for breast cancer. These included statistical features, moment-based features, spectral-energy features, and form-based features. An elaborate variable selection process using logistic regression analyses was performed to identify those features that were associated with case-control status. In addition, PMD was assessed and included in the regression model. Results Of the 470 image-analysis features explored, 46 remained in the final logistic regression model. An area under the curve of 0.79, with an odds ratio per standard deviation change of 2.88 (95% CI, 2.28 to 3.65), was obtained with validation data. Adding the PMD did not improve the final model. Conclusions Using texture features to predict the risk of breast cancer appears feasible. PMD did not show any additional value in this study. With regard to the features assessed, most of the analysis tools appeared to reflect mammographic density, although some features did not correlate with PMD. It remains to be investigated in larger case-control studies whether these features can contribute to increased prediction accuracy. PMID:22490545

[Shigellosis outbreak with 146 cases related to a fair].

PubMed

Castell Monsalve, Juan; Gutiérrez Avila, Gonzalo; Rodolfo Saavedra, Remedios; Santos Azorín, Antonia

2008-01-01

On September 3, 2005, the Ciudad Real Public Health Service (Spain) received a report of 20 cases of gastroenteritis in the municipality of Daimiel. We conducted an investigation to determine the cause or causes of the outbreak and to implement control measures. Most of the cases involved young people who visited the municipality's fair. We carried out a descriptive study and an analytic case-control study. In the descriptive study, all variables of interest available in the medical records were included. In the case-control study, each case was matched with a control by age (plus or minus 5 years), gender, and attendance at the fair. Sixty-five cases and 65 controls were finally included in the study. Samples of foods and stools from food handlers were taken. We found 196 cases, 146 of which were confirmed. The epidemic curve suggested a common source of infection with a short period of activity. The case-control study showed an association between infection and eating potatoes with a sauce at any of the fair's five food stalls (OR = 20.56; 95%CI, 6.15-75.93; p < 0.0001). Logistic regression analysis showed an association with eating potatoes in food stall number 2 (OR = 6.38; 95%CI, 1.70-23.90; p < 0.0059). Neither samples of foods nor stools from food handlers yielded any positive results. However, Shigella sonnei was isolated from stool samples from 20 cases. The epidemiological study suggested that the most probable cause of the outbreak was a sauce, handmade with garlic, milk, and oil and served with the potatoes.

Reducing selection bias in case-control studies from rare disease registries.

PubMed

Cole, J Alexander; Taylor, John S; Hangartner, Thomas N; Weinreb, Neal J; Mistry, Pramod K; Khan, Aneal

2011-09-12

In clinical research of rare diseases, where small patient numbers and disease heterogeneity limit study design options, registries are a valuable resource for demographic and outcome information. However, in contrast to prospective, randomized clinical trials, the observational design of registries is prone to introduce selection bias and negatively impact the validity of data analyses. The objective of the study was to demonstrate the utility of case-control matching and the risk-set method in order to control bias in data from a rare disease registry. Data from the International Collaborative Gaucher Group (ICGG) Gaucher Registry were used as an example. A case-control matching analysis using the risk-set method was conducted to identify two groups of patients with type 1 Gaucher disease in the ICGG Gaucher Registry: patients with avascular osteonecrosis (AVN) and those without AVN. The frequency distributions of gender, decade of birth, treatment status, and splenectomy status were presented for cases and controls before and after matching. Odds ratios (and 95% confidence intervals) were calculated for each variable before and after matching. The application of case-control matching methodology results in cohorts of cases (i.e., patients with AVN) and controls (i.e., patients without AVN) who have comparable distributions for four common parameters used in subject selection: gender, year of birth (age), treatment status, and splenectomy status. Matching resulted in odds ratios of approximately 1.00, indicating no bias. We demonstrated bias in case-control selection in subjects from a prototype rare disease registry and used case-control matching to minimize this bias. Therefore, this approach appears useful to study cohorts of heterogeneous patients in rare disease registries.

A case-control study of the association between ulcerative colitis and hyperthyroidism in an Asian population.

PubMed

Tsai, Ming-Chieh; Lin, Herng-Ching; Lee, Cha-Ze

2017-06-01

Ulcerative colitis (UC) is a chronic relapsing inflammatory disease with significant clinical diversity. However, the aetiology, pathogenesis and optimal treatment of UC remain unclear. The purpose of this case-control study was to investigate the association between previously diagnosed hyperthyroidism and UC using a large population-based data set in Taiwan. The data for this population-based case-control study were retrieved from the Taiwan Longitudinal Health Insurance Database 2005. We included 2709 patients with UC as cases and 8127 sex- and age-matched patients without UC as controls. A conditional logistic regression analysis was conducted to compute the odds ratio (OR) and corresponding 95% confidence interval (CI) for the association between UC and prior hyperthyroidism. We found that, in total, 327 of the 10 836 sampled patients (3.02%) had previously been diagnosed with hyperthyroidism. There was a higher proportion of prior hyperthyroidism among cases than controls (4.10% vs 2.66%, P<.001). A conditional logistic regression showed that the OR of prior hyperthyroidism was 1.57 (95% CI=1.24-1.98) compared to controls. Similarly, after adjusting for monthly income, geographic location and urbanization level, cases were still more likely to have previously been diagnosed with hyperthyroidism than controls (OR=1.61, 95% CI=1.27-2.05). Furthermore, we analysed the ORs of prior hyperthyroidism between cases and controls according to age group. We found that of the youngest group of sampled patients (18-39 years), cases had the greatest adjusted OR for having previously been diagnosed with hyperthyroidism than controls (OR=1.98, 95% CI=1.04-3.79). This study demonstrated an association between UC and hyperthyroidism. © 2017 John Wiley & Sons Ltd.

Continuous overturn control of compactors/rollers by rollover protective structures

PubMed Central

Myers, Melvin L.

2009-01-01

The objective of this article is to report on the effectiveness of Rollover Protective Structures (ROPS) in preventing continuous overturns of compactors/rollers. This study is a case-based analysis of government investigation reports of injury-related overturns of compactors/rollers. The overturns were predominately on construction sites including road and embankment construction in the USA. Other sites included driveway and roadway maintenance or repair and transporting of compactors/rollers either by driving or when loading on or unloading from trailers. The principle intervention observed in controlling a continuous overturn (a roll beyond 90° relative to the impact surface) was the presence of a ROPS on a compactor/roller that serves as an anti-roll bar. The main outcome measures are cases of compactor/roller overturns that are restricted to a 90° roll or are continuous (exceed a 90° roll.) All cases of an overturn in which a ROPS was present resulted in no continuous overturn, and the cases involved with no ROPS averaged an overturn of 301°, showing a propensity for a continuous overturn. This case-based analysis identified a ROPS on compactors/rollers as an effective control for reducing the risk of an overturn to 90° relative to the impact plane. PMID:21765649

Bisphosphonate therapy start may transiently increase the risk of tendon rupture in patients with glucocorticoid co-medication: a population-based observational study.

PubMed

Spoendlin, Julia; Meier, Christian; Jick, Susan S; Meier, Christoph R

2016-10-01

The effect of bisphosphonates on extra-osseous tissue is rarely investigated. We performed an exploratory analysis on the association of new bisphosphonate use and incident tendon rupture in patients with or without oral glucocorticoid co-medication. We conducted a matched case-control study using data from the UK-based Clinical Practice Research Datalink. Cases were patients aged 30-89 years with an incident diagnosis of Achilles or biceps tendon rupture between 1995 and 2013. We compared new oral bisphosphonate use between cases and controls with or without oral glucocorticoid co-medication, by timing (last prescription

Homocysteine and Coronary Heart Disease: Meta-analysis of MTHFR Case-Control Studies, Avoiding Publication Bias

PubMed Central

Verhoef, Petra; Dötsch-Klerk, Mariska; Lathrop, Mark; Xu, Peng; Nordestgaard, Børge G.; Holm, Hilma; Hopewell, Jemma C.; Saleheen, Danish; Tanaka, Toshihiro; Anand, Sonia S.; Chambers, John C.; Kleber, Marcus E.; Ouwehand, Willem H.; Yamada, Yoshiji; Elbers, Clara; Peters, Bas; Stewart, Alexandre F. R.; Reilly, Muredach M.; Thorand, Barbara; Yusuf, Salim; Engert, James C.; Assimes, Themistocles L.; Kooner, Jaspal; Danesh, John; Watkins, Hugh; Samani, Nilesh J.

2012-01-01

Background Moderately elevated blood levels of homocysteine are weakly correlated with coronary heart disease (CHD) risk, but causality remains uncertain. When folate levels are low, the TT genotype of the common C677T polymorphism (rs1801133) of the methylene tetrahydrofolate reductase gene (MTHFR) appreciably increases homocysteine levels, so “Mendelian randomization” studies using this variant as an instrumental variable could help test causality. Methods and Findings Nineteen unpublished datasets were obtained (total 48,175 CHD cases and 67,961 controls) in which multiple genetic variants had been measured, including MTHFR C677T. These datasets did not include measurements of blood homocysteine, but homocysteine levels would be expected to be about 20% higher with TT than with CC genotype in the populations studied. In meta-analyses of these unpublished datasets, the case-control CHD odds ratio (OR) and 95% CI comparing TT versus CC homozygotes was 1.02 (0.98–1.07; p = 0.28) overall, and 1.01 (0.95–1.07) in unsupplemented low-folate populations. By contrast, in a slightly updated meta-analysis of the 86 published studies (28,617 CHD cases and 41,857 controls), the OR was 1.15 (1.09–1.21), significantly discrepant (p = 0.001) with the OR in the unpublished datasets. Within the meta-analysis of published studies, the OR was 1.12 (1.04–1.21) in the 14 larger studies (those with variance of log OR<0.05; total 13,119 cases) and 1.18 (1.09–1.28) in the 72 smaller ones (total 15,498 cases). Conclusions The CI for the overall result from large unpublished datasets shows lifelong moderate homocysteine elevation has little or no effect on CHD. The discrepant overall result from previously published studies reflects publication bias or methodological problems. Please see later in the article for the Editors' Summary PMID:22363213

Longitudinal control effectiveness and entry dynamics of a single-stage-to-orbit vehicle

NASA Technical Reports Server (NTRS)

Vinh, N. X.; Lin, C. F.

1982-01-01

The classical theory of flight dynamics for airplane longitudinal stability and control analysis was extended to the case of a hypervelocity reentry vehicle. This includes the elements inherent in supersonic and hypersonic flight such as the influence of the Mach number on aerodynamic characteristics, and the effect of the reaction control system and aerodynamic controls on the trim condition through a wide range of speed. Phugoid motion and angle of attack oscillation for typical cases of cruising flight, ballistic entry, and glide entry are investigated. In each case, closed form solutions for the variations in altitude, flight path angle, speed and angle of attack are obtained. The solutions explicitly display the influence of different regions design parameters and trajectory variables on the stability of the motion.

Macroinformational analysis of conditions for controllability of space-vehicle orbit

NASA Astrophysics Data System (ADS)

Glazov, B. I.

2011-12-01

The general axiomatics of information measures for the macro analysis of relations of an information-cybernetic system in the control is introduced. The general structure of a semantically marked graph of open and closed relations of an information-cybernetic system between the participants in the environment, as well as thenecessary axiomatic and technological information-cybernetic system conditions of controllability and observability of objects, for the case of a space vehicle in orbit, are justified.

A meta-analysis of genome-wide association studies of breast cancer identifies two novel susceptibility loci at 6q14 and 20q11.

PubMed

Siddiq, Afshan; Couch, Fergus J; Chen, Gary K; Lindström, Sara; Eccles, Diana; Millikan, Robert C; Michailidou, Kyriaki; Stram, Daniel O; Beckmann, Lars; Rhie, Suhn Kyong; Ambrosone, Christine B; Aittomäki, Kristiina; Amiano, Pilar; Apicella, Carmel; Baglietto, Laura; Bandera, Elisa V; Beckmann, Matthias W; Berg, Christine D; Bernstein, Leslie; Blomqvist, Carl; Brauch, Hiltrud; Brinton, Louise; Bui, Quang M; Buring, Julie E; Buys, Saundra S; Campa, Daniele; Carpenter, Jane E; Chasman, Daniel I; Chang-Claude, Jenny; Chen, Constance; Clavel-Chapelon, Françoise; Cox, Angela; Cross, Simon S; Czene, Kamila; Deming, Sandra L; Diasio, Robert B; Diver, W Ryan; Dunning, Alison M; Durcan, Lorraine; Ekici, Arif B; Fasching, Peter A; Feigelson, Heather Spencer; Fejerman, Laura; Figueroa, Jonine D; Fletcher, Olivia; Flesch-Janys, Dieter; Gaudet, Mia M; Gerty, Susan M; Rodriguez-Gil, Jorge L; Giles, Graham G; van Gils, Carla H; Godwin, Andrew K; Graham, Nikki; Greco, Dario; Hall, Per; Hankinson, Susan E; Hartmann, Arndt; Hein, Rebecca; Heinz, Judith; Hoover, Robert N; Hopper, John L; Hu, Jennifer J; Huntsman, Scott; Ingles, Sue A; Irwanto, Astrid; Isaacs, Claudine; Jacobs, Kevin B; John, Esther M; Justenhoven, Christina; Kaaks, Rudolf; Kolonel, Laurence N; Coetzee, Gerhard A; Lathrop, Mark; Le Marchand, Loic; Lee, Adam M; Lee, I-Min; Lesnick, Timothy; Lichtner, Peter; Liu, Jianjun; Lund, Eiliv; Makalic, Enes; Martin, Nicholas G; McLean, Catriona A; Meijers-Heijboer, Hanne; Meindl, Alfons; Miron, Penelope; Monroe, Kristine R; Montgomery, Grant W; Müller-Myhsok, Bertram; Nickels, Stefan; Nyante, Sarah J; Olswold, Curtis; Overvad, Kim; Palli, Domenico; Park, Daniel J; Palmer, Julie R; Pathak, Harsh; Peto, Julian; Pharoah, Paul; Rahman, Nazneen; Rivadeneira, Fernando; Schmidt, Daniel F; Schmutzler, Rita K; Slager, Susan; Southey, Melissa C; Stevens, Kristen N; Sinn, Hans-Peter; Press, Michael F; Ross, Eric; Riboli, Elio; Ridker, Paul M; Schumacher, Fredrick R; Severi, Gianluca; Dos Santos Silva, Isabel; Stone, Jennifer; Sund, Malin; Tapper, William J; Thun, Michael J; Travis, Ruth C; Turnbull, Clare; Uitterlinden, Andre G; Waisfisz, Quinten; Wang, Xianshu; Wang, Zhaoming; Weaver, Joellen; Schulz-Wendtland, Rüdiger; Wilkens, Lynne R; Van Den Berg, David; Zheng, Wei; Ziegler, Regina G; Ziv, Elad; Nevanlinna, Heli; Easton, Douglas F; Hunter, David J; Henderson, Brian E; Chanock, Stephen J; Garcia-Closas, Montserrat; Kraft, Peter; Haiman, Christopher A; Vachon, Celine M

2012-12-15

Genome-wide association studies (GWAS) of breast cancer defined by hormone receptor status have revealed loci contributing to susceptibility of estrogen receptor (ER)-negative subtypes. To identify additional genetic variants for ER-negative breast cancer, we conducted the largest meta-analysis of ER-negative disease to date, comprising 4754 ER-negative cases and 31 663 controls from three GWAS: NCI Breast and Prostate Cancer Cohort Consortium (BPC3) (2188 ER-negative cases; 25 519 controls of European ancestry), Triple Negative Breast Cancer Consortium (TNBCC) (1562 triple negative cases; 3399 controls of European ancestry) and African American Breast Cancer Consortium (AABC) (1004 ER-negative cases; 2745 controls). We performed in silico replication of 86 SNPs at P ≤ 1 × 10(-5) in an additional 11 209 breast cancer cases (946 with ER-negative disease) and 16 057 controls of Japanese, Latino and European ancestry. We identified two novel loci for breast cancer at 20q11 and 6q14. SNP rs2284378 at 20q11 was associated with ER-negative breast cancer (combined two-stage OR = 1.16; P = 1.1 × 10(-8)) but showed a weaker association with overall breast cancer (OR = 1.08, P = 1.3 × 10(-6)) based on 17 869 cases and 43 745 controls and no association with ER-positive disease (OR = 1.01, P = 0.67) based on 9965 cases and 22 902 controls. Similarly, rs17530068 at 6q14 was associated with breast cancer (OR = 1.12; P = 1.1 × 10(-9)), and with both ER-positive (OR = 1.09; P = 1.5 × 10(-5)) and ER-negative (OR = 1.16, P = 2.5 × 10(-7)) disease. We also confirmed three known loci associated with ER-negative (19p13) and both ER-negative and ER-positive breast cancer (6q25 and 12p11). Our results highlight the value of large-scale collaborative studies to identify novel breast cancer risk loci.

A meta-analysis of genome-wide association studies of breast cancer identifies two novel susceptibility loci at 6q14 and 20q11

PubMed Central

Siddiq, Afshan; Couch, Fergus J.; Chen, Gary K.; Lindström, Sara; Eccles, Diana; Millikan, Robert C.; Michailidou, Kyriaki; Stram, Daniel O.; Beckmann, Lars; Rhie, Suhn Kyong; Ambrosone, Christine B.; Aittomäki, Kristiina; Amiano, Pilar; Apicella, Carmel; Baglietto, Laura; Bandera, Elisa V.; Beckmann, Matthias W.; Berg, Christine D.; Bernstein, Leslie; Blomqvist, Carl; Brauch, Hiltrud; Brinton, Louise; Bui, Quang M.; Buring, Julie E.; Buys, Saundra S.; Campa, Daniele; Carpenter, Jane E.; Chasman, Daniel I.; Chang-Claude, Jenny; Chen, Constance; Clavel-Chapelon, Françoise; Cox, Angela; Cross, Simon S.; Czene, Kamila; Deming, Sandra L.; Diasio, Robert B.; Diver, W. Ryan; Dunning, Alison M.; Durcan, Lorraine; Ekici, Arif B.; Fasching, Peter A.; Feigelson, Heather Spencer; Fejerman, Laura; Figueroa, Jonine D.; Fletcher, Olivia; Flesch-Janys, Dieter; Gaudet, Mia M.; Gerty, Susan M.; Rodriguez-Gil, Jorge L.; Giles, Graham G.; van Gils, Carla H.; Godwin, Andrew K.; Graham, Nikki; Greco, Dario; Hall, Per; Hankinson, Susan E.; Hartmann, Arndt; Hein, Rebecca; Heinz, Judith; Hoover, Robert N.; Hopper, John L.; Hu, Jennifer J.; Huntsman, Scott; Ingles, Sue A.; Irwanto, Astrid; Isaacs, Claudine; Jacobs, Kevin B.; John, Esther M.; Justenhoven, Christina; Kaaks, Rudolf; Kolonel, Laurence N.; Coetzee, Gerhard A.; Lathrop, Mark; Le Marchand, Loic; Lee, Adam M.; Lee, I-Min; Lesnick, Timothy; Lichtner, Peter; Liu, Jianjun; Lund, Eiliv; Makalic, Enes; Martin, Nicholas G.; McLean, Catriona A.; Meijers-Heijboer, Hanne; Meindl, Alfons; Miron, Penelope; Monroe, Kristine R.; Montgomery, Grant W.; Müller-Myhsok, Bertram; Nickels, Stefan; Nyante, Sarah J.; Olswold, Curtis; Overvad, Kim; Palli, Domenico; Park, Daniel J.; Palmer, Julie R.; Pathak, Harsh; Peto, Julian; Pharoah, Paul; Rahman, Nazneen; Rivadeneira, Fernando; Schmidt, Daniel F.; Schmutzler, Rita K.; Slager, Susan; Southey, Melissa C.; Stevens, Kristen N.; Sinn, Hans-Peter; Press, Michael F.; Ross, Eric; Riboli, Elio; Ridker, Paul M.; Schumacher, Fredrick R.; Severi, Gianluca; dos Santos Silva, Isabel; Stone, Jennifer; Sund, Malin; Tapper, William J.; Thun, Michael J.; Travis, Ruth C.; Turnbull, Clare; Uitterlinden, Andre G.; Waisfisz, Quinten; Wang, Xianshu; Wang, Zhaoming; Weaver, JoEllen; Schulz-Wendtland, Rüdiger; Wilkens, Lynne R.; Van Den Berg, David; Zheng, Wei; Ziegler, Regina G.; Ziv, Elad; Nevanlinna, Heli; Easton, Douglas F.; Hunter, David J.; Henderson, Brian E.; Chanock, Stephen J.; Garcia-Closas, Montserrat; Kraft, Peter; Haiman, Christopher A.; Vachon, Celine M.

2012-01-01

Genome-wide association studies (GWAS) of breast cancer defined by hormone receptor status have revealed loci contributing to susceptibility of estrogen receptor (ER)-negative subtypes. To identify additional genetic variants for ER-negative breast cancer, we conducted the largest meta-analysis of ER-negative disease to date, comprising 4754 ER-negative cases and 31 663 controls from three GWAS: NCI Breast and Prostate Cancer Cohort Consortium (BPC3) (2188 ER-negative cases; 25 519 controls of European ancestry), Triple Negative Breast Cancer Consortium (TNBCC) (1562 triple negative cases; 3399 controls of European ancestry) and African American Breast Cancer Consortium (AABC) (1004 ER-negative cases; 2745 controls). We performed in silico replication of 86 SNPs at P ≤ 1 × 10-5 in an additional 11 209 breast cancer cases (946 with ER-negative disease) and 16 057 controls of Japanese, Latino and European ancestry. We identified two novel loci for breast cancer at 20q11 and 6q14. SNP rs2284378 at 20q11 was associated with ER-negative breast cancer (combined two-stage OR = 1.16; P = 1.1 × 10−8) but showed a weaker association with overall breast cancer (OR = 1.08, P = 1.3 × 10–6) based on 17 869 cases and 43 745 controls and no association with ER-positive disease (OR = 1.01, P = 0.67) based on 9965 cases and 22 902 controls. Similarly, rs17530068 at 6q14 was associated with breast cancer (OR = 1.12; P = 1.1 × 10−9), and with both ER-positive (OR = 1.09; P = 1.5 × 10−5) and ER-negative (OR = 1.16, P = 2.5 × 10−7) disease. We also confirmed three known loci associated with ER-negative (19p13) and both ER-negative and ER-positive breast cancer (6q25 and 12p11). Our results highlight the value of large-scale collaborative studies to identify novel breast cancer risk loci. PMID:22976474

Bipolar disorder with binge eating behavior: a genome-wide association study implicates PRR5-ARHGAP8.

PubMed

McElroy, Susan L; Winham, Stacey J; Cuellar-Barboza, Alfredo B; Colby, Colin L; Ho, Ada Man-Choi; Sicotte, Hugues; Larrabee, Beth R; Crow, Scott; Frye, Mark A; Biernacka, Joanna M

2018-02-02

Bipolar disorder (BD) is associated with binge eating behavior (BE), and both conditions are heritable. Previously, using data from the Genetic Association Information Network (GAIN) study of BD, we performed genome-wide association (GWA) analyses of BD with BE comorbidity. Here, utilizing data from the Mayo Clinic BD Biobank (969 BD cases, 777 controls), we performed a GWA analysis of a BD subtype defined by BE, and case-only analysis comparing BD subjects with and without BE. We then performed a meta-analysis of the Mayo and GAIN results. The meta-analysis provided genome-wide significant evidence of association between single nucleotide polymorphisms (SNPs) in PRR5-ARHGAP8 and BE in BD cases (rs726170 OR = 1.91, P = 3.05E-08). In the meta-analysis comparing cases with BD with comorbid BE vs. non-BD controls, a genome-wide significant association was observed at SNP rs111940429 in an intergenic region near PPP1R2P5 (p = 1.21E-08). PRR5-ARHGAP8 is a read-through transcript resulting in a fusion protein of PRR5 and ARHGAP8. PRR5 encodes a subunit of mTORC2, a serine/threonine kinase that participates in food intake regulation, while ARHGAP8 encodes a member of the RhoGAP family of proteins that mediate cross-talk between Rho GTPases and other signaling pathways. Without BE information in controls, it is not possible to determine whether the observed association reflects a risk factor for BE in general, risk for BE in individuals with BD, or risk of a subtype of BD with BE. The effect of PRR5-ARHGAP8 on BE risk thus warrants further investigation.

Alcohol consumption and lung cancer risk in never smokers: a pooled analysis of case-control studies.

PubMed

García Lavandeira, José A; Ruano-Ravina, Alberto; Kelsey, Karl T; Torres-Durán, María; Parente-Lamelas, Isaura; Leiro-Fernández, Virginia; Zapata, Maruxa; Abal-Arca, José; Vidal-García, Iria; Montero-Martínez, Carmen; Amenedo, Margarita; Castro-Añón, Olalla; Golpe-Gómez, Antonio; Guzmán-Taveras, Rosirys; Martínez, Cristina; Provencio, Mariano; Mejuto-Martí, María J; García-García, Silvia; Fernández-Villar, Alberto; Piñeiro, María; Barros-Dios, Juan M

2018-06-01

Lung cancer is the deadliest cancer in developed countries but the etiology of lung cancer risk in never smokers (LCRINS) is largely unknown. We aim to assess the effects of alcohol consumption, in its different forms, on LCRINS. We pooled six multi-center case-control studies developed in the northwest of Spain. Cases and controls groups were composed of never smokers. We selected incident cases with anatomopathologically confirmed lung cancer diagnoses. All participants were personally interviewed. We performed two groups of statistical models, applying unconditional logistic regression with generalized additive models. One considered the effect of alcohol type consumption and the other considered the quantity of each alcoholic beverage consumed. A total of 438 cases and 863 controls were included. Median age was 71 and 66, years, respectively. Adenocarcinoma was the predominant histological type, comprising 66% of all cases. We found that any type of wine consumption posed an OR of 2.20 OR 95%CI 1.12-4.35), and spirits consumption had an OR of 1.90 (95%CI 1.13-3.23). Beer consumption had an OR of 1.33 (95%CI 0.82-2.14). These results were similar when women were analyzed separately, but for men there was no apparent risk for any alcoholic beverage. The dose-response analysis for each alcoholic beverage revealed no clear pattern. Wine and spirits consumption might increase the risk of LCRINSs, particularly in females. These results have to be taken with caution given the limitations of the present study.

Melasma and its association with different types of nevi in women: A case-control study

PubMed Central

Adalatkhah, Hassan; Sadeghi-bazargani, Homayoun; Amini-sani, Nayereh; Zeynizadeh, Somayeh

2008-01-01

Background Very little is known about possible association of nevi and melasma. The study objective was to determine if there is an association between melasma and existence of different kinds of nevi. Methods In a case-control study, 120 female melasma patients referred to dermatology clinic of Ardabil and 120 patients referred to other specialty clinics who lacked melasma were enrolled after matching for age. Number of different types of nevi including lentigines and melanocytic nevi were compared between case and control group patients. Data were entered into the computer and analyzed by SPSS 13 statistical software. Results Mean number of lentigines was 25.5 in melasma group compared to 8 in control group(P < 0.01). Mean number of melanocytic nevi was 13.2 in cases compared to 2.8 in control group(P < 0.001). Multivariate analysis showed that existence of freckles, lentigines and more than three melanocytic nevi were positively related to developing melasma. The chance of melasma increased up to 23 times for patients having more than three melanocytic nevi. Congenital nevi were observed among 10% both in case and control groups. Campbell de morgan angiomas were seen among 26 patients(21.8%) in case group compared to 6 patients(5%) in control group. Conclusion Existence of lentigines and melanocytic nevi increases chance of having melasma PMID:18680608

Impact of payment system change from per-case to per-diem on high severity patient's length of stay.

PubMed

Jang, Sung-In; Nam, Chung Mo; Lee, Sang Gyu; Kim, Tae Hyun; Park, Sohee; Park, Eun-Cheol

2016-09-01

A new payment system, the diagnosis-related group (DRG) system, and Korean diagnosis procedure combination (KDPC, per-diem) payment system were officially introduced in 2002 and in 2012, respectively. We evaluated the impact of payment system change from per-case to per-diem on high severity patient's length of stay (LOS).Claim data was used. A total of 36,240 case admissions and 72,480 control admissions were included in the analysis. Segmented regression analysis of interrupted time series between cases and controls was conducted. Hospitals that consistently participated in the DRG payment system and changed to the KDPC payment system were defined as case hospitals. Hospitals that consistently participated in the DRG payment system were defined as control hospitals.LOS increased by 0.025 days per month (P = 0.0055) for 3 surgical diagnosis-related admissions due to the bundled payment system change. LOS among emergency admissions also increased and showed an increasing tendency under the KDPC. The LOS increase was observed specifically for complex procedure admissions and high severity cases (CCI 0, 1: 0.022, P = 0.0142; CCI 2, 3: 0.026, P = 0.0288; CCI ≥ 4: 0.055, P = 0.0003).Although both payment systems are optimized to decrease LOS, incentives to reduce LOS are stronger under the DRG system than under the KDPC system. It is worth noting that too strong incentive for reducing LOS is suitable to high severity cases.

Neuropathological findings processed by artificial neural networks (ANNs) can perfectly distinguish Alzheimer's patients from controls in the Nun Study

PubMed Central

Grossi, Enzo; Buscema, Massimo P; Snowdon, David; Antuono, Piero

2007-01-01

Background Many reports have described that there are fewer differences in AD brain neuropathologic lesions between AD patients and control subjects aged 80 years and older, as compared with the considerable differences between younger persons with AD and controls. In fact some investigators have suggested that since neurofibrillary tangles (NFT) can be identified in the brains of non-demented elderly subjects they should be considered as a consequence of the aging process. At present, there are no universally accepted neuropathological criteria which can mathematically differentiate AD from healthy brain in the oldest old. The aim of this study is to discover the hidden and non-linear associations among AD pathognomonic brain lesions and the clinical diagnosis of AD in participants in the Nun Study through Artificial Neural Networks (ANNs) analysis Methods The analyses were based on 26 clinically- and pathologically-confirmed AD cases and 36 controls who had normal cognitive function. The inputs used for the analyses were just NFT and neuritic plaques counts in neocortex and hippocampus, for which, despite substantial differences in mean lesions counts between AD cases and controls, there was a substantial overlap in the range of lesion counts. Results By taking into account the above four neuropathological features, the overall predictive capability of ANNs in sorting out AD cases from normal controls reached 100%. The corresponding accuracy obtained with Linear Discriminant Analysis was 92.30%. These results were consistently obtained in ten independent experiments. The same experiments were carried out with ANNs on a subgroup of 13 non severe AD patients and on the same 36 controls. The results obtained in terms of prediction accuracy with ANNs were exactly the same. Input relevance analysis confirmed the relative dominance of NFT in neocortex in discriminating between AD patients and controls and indicated the lesser importance played by NP in the hippocampus. Conclusion The results of this study suggest that: a) cortical NFT represent the key variable in AD neuropathology; b) the neuropathologic profile of AD subjects is complex, however, c) ANNs can analyze neuropathologic features and differentiate AD cases from controls. PMID:17584929

Neuropathological findings processed by artificial neural networks (ANNs) can perfectly distinguish Alzheimer's patients from controls in the Nun Study.

PubMed

Grossi, Enzo; Buscema, Massimo P; Snowdon, David; Antuono, Piero

2007-06-21

Many reports have described that there are fewer differences in AD brain neuropathologic lesions between AD patients and control subjects aged 80 years and older, as compared with the considerable differences between younger persons with AD and controls. In fact some investigators have suggested that since neurofibrillary tangles (NFT) can be identified in the brains of non-demented elderly subjects they should be considered as a consequence of the aging process. At present, there are no universally accepted neuropathological criteria which can mathematically differentiate AD from healthy brain in the oldest old. The aim of this study is to discover the hidden and non-linear associations among AD pathognomonic brain lesions and the clinical diagnosis of AD in participants in the Nun Study through Artificial Neural Networks (ANNs) analysis The analyses were based on 26 clinically- and pathologically-confirmed AD cases and 36 controls who had normal cognitive function. The inputs used for the analyses were just NFT and neuritic plaques counts in neocortex and hippocampus, for which, despite substantial differences in mean lesions counts between AD cases and controls, there was a substantial overlap in the range of lesion counts. By taking into account the above four neuropathological features, the overall predictive capability of ANNs in sorting out AD cases from normal controls reached 100%. The corresponding accuracy obtained with Linear Discriminant Analysis was 92.30%. These results were consistently obtained in ten independent experiments. The same experiments were carried out with ANNs on a subgroup of 13 non severe AD patients and on the same 36 controls. The results obtained in terms of prediction accuracy with ANNs were exactly the same. Input relevance analysis confirmed the relative dominance of NFT in neocortex in discriminating between AD patients and controls and indicated the lesser importance played by NP in the hippocampus. The results of this study suggest that: a) cortical NFT represent the key variable in AD neuropathology; b) the neuropathologic profile of AD subjects is complex, however, c) ANNs can analyze neuropathologic features and differentiate AD cases from controls.

Development of myoelectric control type speaking valve with low flow resistance

NASA Astrophysics Data System (ADS)

Ooe, Katsutoshi; Sakurai, Kohei; Mimaki, Shinya

2015-12-01

We aimed to develop welfare devices for patients with phonation disorder. One of these devices is the electrical controltype speaking valve system. The conventional speaking valves have one-way valve architecture, they open when the user breathes in, and they close when user breathes out and produce voices. This type is very simple and tough, but some users feel closeness in case of exhalation without phonation. This problem is caused by its mechanism what can not be controlled by user's will. Therefore, we proposed an electrical control-type speaking valve system to resolve this problem. This valve is controlled by neck myoelectric signal of sternohyoid muscle. From our previous report, it was clarified that this valve had better performance about easy-to-breath. Furthermore, we proposed the compact myoelectric control-type speaking valve system. The new-type speaking valve was enough small to attach the human body, and its opening area is larger than that of conventional one. Additionally, we described the improvement of flow channel shape by using of FEM analysis. According to the result of the analysis, it was clarified that the shape-improved speaking valve gets the low flow resistance channel in case of inspiration. In this report, we tried to make the flow resistance lower by the shape of current plates, in case of both inspiration and exhalation. From the result of FEM analysis, our speaking valve could get better flow channel than older one.

Childhood Adversities Increase the Risk of Psychosis: A Meta-analysis of Patient-Control, Prospective- and Cross-sectional Cohort Studies

PubMed Central

Varese, Filippo; Smeets, Feikje; Drukker, Marjan; Lieverse, Ritsaert; Lataster, Tineke; Viechtbauer, Wolfgang; Read, John; van Os, Jim; Bentall, Richard P.

2012-01-01

Evidence suggests that adverse experiences in childhood are associated with psychosis. To examine the association between childhood adversity and trauma (sexual abuse, physical abuse, emotional/psychological abuse, neglect, parental death, and bullying) and psychosis outcome, MEDLINE, EMBASE, PsychINFO, and Web of Science were searched from January 1980 through November 2011. We included prospective cohort studies, large-scale cross-sectional studies investigating the association between childhood adversity and psychotic symptoms or illness, case-control studies comparing the prevalence of adverse events between psychotic patients and controls using dichotomous or continuous measures, and case-control studies comparing the prevalence of psychotic symptoms between exposed and nonexposed subjects using dichotomous or continuous measures of adversity and psychosis. The analysis included 18 case-control studies (n = 2048 psychotic patients and 1856 nonpsychiatric controls), 10 prospective and quasi-prospective studies (n = 41 803) and 8 population-based cross-sectional studies (n = 35 546). There were significant associations between adversity and psychosis across all research designs, with an overall effect of OR = 2.78 (95% CI = 2.34–3.31). The integration of the case-control studies indicated that patients with psychosis were 2.72 times more likely to have been exposed to childhood adversity than controls (95% CI = 1.90–3.88). The association between childhood adversity and psychosis was also significant in population-based cross-sectional studies (OR = 2.99 [95% CI = 2.12–4.20]) as well as in prospective and quasi-prospective studies (OR = 2.75 [95% CI = 2.17–3.47]). The estimated population attributable risk was 33% (16%–47%). These findings indicate that childhood adversity is strongly associated with increased risk for psychosis. PMID:22461484

Cadmium exposure and risk of prostate cancer: a meta-analysis of cohort and case-control studies among the general and occupational populations

PubMed Central

Chen, Cheng; Xun, Pengcheng; Nishijo, Muneko; Carter, Sue; He, Ka

2016-01-01

We aimed to evaluate the association of cadmium exposure with the risk of prostate cancer in both the general and occupational populations. Online database searches were performed for studies of prostate cancer risk and cadmium exposure. Twelve cohort studies (5 in the general, 7 in occupational populations) and 9 case-control studies (3 in the general, 6 in occupational populations) were identified. Five/seven cohort studies in the general and occupational populations consist of 78,263/13, 434 participants with a mean follow-up of 12.1/43.0 years, respectively. Case-control studies include 334 cases/670 controls in the general population, and 1,315 cases/4,477 controls in occupational populations. Comparing the highest to the lowest category of cadmium exposure in the general population, the weighted relative risk of prostate cancer incidence and mortality among cohort studies, and the weighted odds ratio in case-control studies were 1.05 (95%CI [0.91, 1.22]), 0.83 (95%CI [0.35, 1.98]), and 1.27 (95%CI [0.58,2.78]), respectively. For occupational populations, the weighted OR in case-control studies was 1.17 (95%CI [0.85, 1.62]), and the weighted standardized mortality ratio in cohort studies was 98 (95%CI [75, 126]). Accumulated epidemiological evidence does not support the hypothesis that cadmium exposure may increase the risk of prostate cancer in either the general or occupational populations. PMID:27174617

Cadmium exposure and risk of prostate cancer: a meta-analysis of cohort and case-control studies among the general and occupational populations.

PubMed

Chen, Cheng; Xun, Pengcheng; Nishijo, Muneko; Carter, Sue; He, Ka

2016-05-13

We aimed to evaluate the association of cadmium exposure with the risk of prostate cancer in both the general and occupational populations. Online database searches were performed for studies of prostate cancer risk and cadmium exposure. Twelve cohort studies (5 in the general, 7 in occupational populations) and 9 case-control studies (3 in the general, 6 in occupational populations) were identified. Five/seven cohort studies in the general and occupational populations consist of 78,263/13, 434 participants with a mean follow-up of 12.1/43.0 years, respectively. Case-control studies include 334 cases/670 controls in the general population, and 1,315 cases/4,477 controls in occupational populations. Comparing the highest to the lowest category of cadmium exposure in the general population, the weighted relative risk of prostate cancer incidence and mortality among cohort studies, and the weighted odds ratio in case-control studies were 1.05 (95%CI [0.91, 1.22]), 0.83 (95%CI [0.35, 1.98]), and 1.27 (95%CI [0.58,2.78]), respectively. For occupational populations, the weighted OR in case-control studies was 1.17 (95%CI [0.85, 1.62]), and the weighted standardized mortality ratio in cohort studies was 98 (95%CI [75, 126]). Accumulated epidemiological evidence does not support the hypothesis that cadmium exposure may increase the risk of prostate cancer in either the general or occupational populations.

Cluster randomised controlled trial to examine medical mask use as source control for people with respiratory illness.

PubMed

MacIntyre, Chandini Raina; Zhang, Yi; Chughtai, Abrar Ahmad; Seale, Holly; Zhang, Daitao; Chu, Yanhui; Zhang, Haiyan; Rahman, Bayzidur; Wang, Quanyi

2016-12-30

Medical masks are commonly used by sick individuals with influenza-like illness (ILI) to prevent spread of infections to others, but clinical efficacy data are absent. Determine whether medical mask use by sick individuals with ILI protects well contacts from related respiratory infections. 6 major hospitals in 2 districts of Beijing, China. Cluster randomised controlled trial. 245 index cases with ILI. Index cases with ILI were randomly allocated to medical mask (n=123) and control arms (n=122). Since 43 index cases in the control arm also used a mask during the study period, an as-treated post hoc analysis was performed by comparing outcomes among household members of index cases who used a mask (mask group) with household members of index cases who did not use a mask (no-mask group). Primary outcomes measured in household members were clinical respiratory illness, ILI and laboratory-confirmed viral respiratory infection. In an intention-to-treat analysis, rates of clinical respiratory illness (relative risk (RR) 0.61, 95% CI 0.18 to 2.13), ILI (RR 0.32, 95% CI 0.03 to 3.13) and laboratory-confirmed viral infections (RR 0.97, 95% CI 0.06 to 15.54) were consistently lower in the mask arm compared with control, although not statistically significant. A post hoc comparison between the mask versus no-mask groups showed a protective effect against clinical respiratory illness, but not against ILI and laboratory-confirmed viral respiratory infections. The study indicates a potential benefit of medical masks for source control, but is limited by small sample size and low secondary attack rates. Larger trials are needed to confirm efficacy of medical masks as source control. ACTRN12613000852752; Results. 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/.

Cluster randomised controlled trial to examine medical mask use as source control for people with respiratory illness

PubMed Central

MacIntyre, Chandini Raina; Zhang, Yi; Chughtai, Abrar Ahmad; Seale, Holly; Zhang, Daitao; Chu, Yanhui; Zhang, Haiyan; Rahman, Bayzidur; Wang, Quanyi

2016-01-01

Rationale Medical masks are commonly used by sick individuals with influenza-like illness (ILI) to prevent spread of infections to others, but clinical efficacy data are absent. Objective Determine whether medical mask use by sick individuals with ILI protects well contacts from related respiratory infections. Setting 6 major hospitals in 2 districts of Beijing, China. Design Cluster randomised controlled trial. Participants 245 index cases with ILI. Intervention Index cases with ILI were randomly allocated to medical mask (n=123) and control arms (n=122). Since 43 index cases in the control arm also used a mask during the study period, an as-treated post hoc analysis was performed by comparing outcomes among household members of index cases who used a mask (mask group) with household members of index cases who did not use a mask (no-mask group). Main outcome measure Primary outcomes measured in household members were clinical respiratory illness, ILI and laboratory-confirmed viral respiratory infection. Results In an intention-to-treat analysis, rates of clinical respiratory illness (relative risk (RR) 0.61, 95% CI 0.18 to 2.13), ILI (RR 0.32, 95% CI 0.03 to 3.13) and laboratory-confirmed viral infections (RR 0.97, 95% CI 0.06 to 15.54) were consistently lower in the mask arm compared with control, although not statistically significant. A post hoc comparison between the mask versus no-mask groups showed a protective effect against clinical respiratory illness, but not against ILI and laboratory-confirmed viral respiratory infections. Conclusions The study indicates a potential benefit of medical masks for source control, but is limited by small sample size and low secondary attack rates. Larger trials are needed to confirm efficacy of medical masks as source control. Trial registration number ACTRN12613000852752; Results. PMID:28039289

[Risk factors for the kidney stones: a hospital-based case-control study in a distric hospital in Beijing].

PubMed

Wang, Jiao; Luo, Gong-tang; Niu, Wei-jing; Gong, Man-man; Liu, Lu; Zhou, Jie; Zhou, Xue-wei; He, Li-hua

2013-12-18

To explore the risk and protective factors of kidney calculi in order to put forward theoretical basis for preventive and control measures. A 1:1 matched case-control study was performed using data from a hospital in Beijing. The case group included 100 inpatients who were diagnosed kidney calculi using B ultrasonic, X-ray and intravenous pyelography during the survey while other 100 urolithiasis and endocrine disease excluded inpatients who shared the same sex, within five years gap to the case group inpatients were for the control group. A face-to-face survey was conducted with self-made questionnaires which covered demographic characteristics, water issues, dietary habits, genetic and medical history. Epidata 3.0 was used to build the database and SPSS 19.0 for the statistical analysis. In the univariate Logistic regression analysis, ten variables were found showing statistical significance. For the multivariate Logistic regression analysis, variables left in the model were labor intensity (OR=0.622, 95%CI: 0.435-0.889), preferring to drink after dinner (OR=0.316, 95%CI: 0.122-0.815), loving drinking (OR=0.232, 95%CI: 0.084-0.642), drinking tea regularly (OR=1.463, 95%CI: 1.033-2.071), eating more vegetables (OR=0.571, 95%CI: 0.328-0.993), the history of the urolithiasis (OR=2.127, 95%CI: 1.065-90.145). Drinking tea regularly, urolithiasis history and brain work are the risk factors of kidney calculi while loving drinking and eating more vegetables for the protection.

Coffee Consumption and the Risk of Thyroid Cancer: A Systematic Review and Meta-Analysis

PubMed Central

Han, Mi Ah; Kim, Jin Hwa

2017-01-01

An inverse association has been reported between coffee consumption and the risk of several cancers. However, the association between coffee and thyroid cancer is controversial. Thus, this study aimed to evaluate the association between coffee consumption and the risk of thyroid cancer through a systematic review and meta-analysis. Published studies were examined from PubMed, Embase, Cochrane Central, and the reference lists of the retrieved articles. The summary odds ratio (OR) for the association between coffee consumption was categorized as highest versus lowest consumption, and thyroid cancer risk was calculated using a fixed effects model. Subgroup analyses by study design, geographic location, source of controls, and adjusted variables were performed. A total of 1039 thyroid cancer cases and 220,816 controls were identified from five case-control studies and two cohort studies. The summary OR for the association between coffee consumption and thyroid cancer risk was 0.88 (95% confidence interval (CI) = 0.71–1.07). There was no significant heterogeneity among the study results (I² = 0%, p = 0.79). However, the beneficial effect of coffee consumption on thyroid cancer was found only in hospital-based case-control studies (OR= 0.59, 95% CI= 0.37–0.93). There was no significant association between coffee consumption and thyroid cancer risk according to our meta-analysis results. These findings should be interpreted with caution because of potential biases and confounding variables. Further prospective studies with a larger number of cases are encouraged to confirm these results. PMID:28134794

The MTHFR C677T polymorphism and risk of acute lymphoblastic leukemia: an updated meta-analysis based on 37 case-control studies.

PubMed

Jiang, Yuan; Hou, Jing; Zhang, Qiang; Jia, Shu-Ting; Wang, Bo-Yuan; Zhang, Ji-Hong; Tang, Wen-Ru; Luo, Ying

2013-01-01

The C677T polymorphism of the methylenetetrahydrofolate reductase (MTHFR) has been associated with acute lymphoblastic leukemia (ALL). However, results were conflicting. The aim of this study was to quantitatively summarize the evidence for the MTHFRC677T polymorphism and ALL risk. Electronic searches of PubMed and the Chinese Biomedicine database were conducted to select case-control studies containing available genotype frequencies of C677T and the odds ratio (OR) with 95% confidence interval (CI) was used to assess the strength of any association. Case-control studies including 6,371 cases and 10,850 controls were identified. The meta-analysis stratified by ethnicity showed that individuals with the homozygous TT genotype had decreased risk of ALL (OR= 0.776, 95% CI: 0.687~0.877, p< 0.001) in Caucasians (OR= 0.715, 95% CI: 0.655~0.781, p= 0.000). However, results among Asians (OR=0.711, 95% CI: 0.591~1.005, p= 0.055) and others (OR=0.913, 95% CI: 0.656~1.271, p= 0. 590) did not suggest an association. A symmetric funnel plot, the Egger's test (P=0.093), and the Begg- test (P=0.072) were all suggestive of the lack of publication bias. This meta-analysis supports the idea that the MTHFR C677T genotype is associated with risk of ALL in Caucasians. To draw comprehensive and true conclusions, further prospective studies with larger numbers of participants worldwide are needed to examine associations between the MTHFRC677T polymorphism and ALL.

Risk factors for Staphylococcus aureus postpartum breast abscess.

PubMed

Branch-Elliman, Westyn; Golen, Toni H; Gold, Howard S; Yassa, David S; Baldini, Linda M; Wright, Sharon B

2012-01-01

Staphylococcus aureus (SA) breast abscesses are a complication of the postpartum period. Risk factors for postpartum SA breast abscesses are poorly defined, and literature is conflicting. Whether risk factors for methicillin-resistant SA (MRSA) and methicillin-susceptible SA (MSSA) infections differ is unknown. We describe novel risk factors associated with postpartum breast abscesses and the changing epidemiology of this infection. We conducted a cohort study with a nested case-control study (n = 216) involving all patients with culture-confirmed SA breast abscess among >30 000 deliveries at our academic tertiary care center from 2003 through 2010. Data were collected from hospital databases and through abstraction from medical records. All SA cases were compared with both nested controls and full cohort controls. A subanalysis was completed to determine whether risk factors for MSSA and MRSA breast abscess differ. Univariate analysis was completed using Student's t test, Wilcoxon rank-sum test, and analysis of variance, as appropriate. A multivariable stepwise logistic regression was used to determine final adjusted results for both the case-control and the cohort analyses. Fifty-four cases of culture-confirmed abscess were identified: 30 MRSA and 24 MSSA. Risk factors for postpartum SA breast abscess in multivariable analysis include in-hospital identification of a mother having difficulty breastfeeding (odds ratio, 5.00) and being a mother employed outside the home (odds ratio, 2.74). Risk factors did not differ between patients who developed MRSA and MSSA infections. MRSA is an increasingly important pathogen in postpartum women; risk factors for postpartum SA breast abscess have not changed with the advent of community-associated MRSA.

Dermal Structure in Lymphedema Patients with History of Acute Dermatolymphangioadenitis Evaluated by Histogram Analysis of Ultrasonography Findings: A Case-Control Study.

PubMed

Dai, Misako; Sato, Aya; Maeba, Hiroko; Iuchi, Terumi; Matsumoto, Masaru; Okuwa, Mayumi; Nakatani, Toshio; Sanada, Hiromi; Sugama, Junko

2016-03-01

Acute dermatolymphangioadenitis (ADLA) is a risk factor for increasing of edema and worsening severity. Reducing ADLA frequency is an important objective of lymphedema management because ADLA episodes are strongly associated with poor quality of life. Lymphedema changes dermal and subcutaneous structure, favoring ADLA; ADLA recurrence may be caused by structural change of the dermis. However, the structure of the skin following ADLA episodes has not been studied in depth. The aim of this study was to examine changes in the skin after episodes of ADLA in breast cancer-related lymphedema (BCRL) using histogram analysis of ultrasonography findings. This was a case-control study with matching for the duration of lymphedema. We compared 10 limbs (5 BCRL patients, Cases) with a history of ADLA and 14 limbs (7 BCRL patients, Controls) without. Ultrasonography was performed using a 20-MHz probe, and measurements were made at a site 10 cm proximal to the ulnar styloid process. We compared "skewness" of the images in the dermis from the histogram analysis. This study was approved by the Ethics Committee of Kanazawa University. Skewness was significantly different between the affected and unaffected limbs (p = 0.02). Cases showed a positive value (median 0.74, range -0.18 to 1.26), whereas Controls showed a negative value (median -0.21, range -0.45 to 0.31). Episodes of ADLA changed the distribution of echogenicity on imaging, which indicates a change in the collagen fibers in the dermis. These findings might contribute to improving the management of lymphedema and prevention of recurrent ADLA.

Poor Metabolizers at the Cytochrome P450 2C19 Loci Is at Increased Risk of Developing Cancer in Asian Populations

PubMed Central

Chen, Zenggan; Yu, Yanmin

2013-01-01

Background CYP2C19 encodes a member of the cytochrome P450 superfamily of enzymes, which play a central role in activating and detoxifying many carcinogens and endogenous compounds thought to be involved in the development of cancer. In the past decade, two common polymorphisms among CYP2C19 (CYP2C19*2 and CYP2C19*3) that are responsible for the poor metabolizers (PMs) phenotype in humans and cancer susceptibility have been investigated extensively; however, these studies have yielded contradictory results. Methods and Results To investigate this inconsistency, we conducted a comprehensive meta-analysis of 11,554 cases and 16,592 controls from 30 case-control studies. Overall, the odds ratio (OR) of cancer was 1.52 [95% confidence interval (CI): 1.23–1.88, P<10-4] for CYP2C19 PMs genotypes. However, this significant association vanished when the analyses were restricted to 5 larger studies (no. of cases ≥ 500 cases). In the subgroup analysis for different cancer types, PMs genotypes had an effect of increasing the risks of esophagus cancer, gastric cancer, lung cancer and hepatocellular carcinoma as well as head neck cancer. Significant results were found in Asian populations when stratified by ethnicity; whereas no significant associations were found among Caucasians. Stratified analyses according to source of controls, significant associations were found only in hospital base controls. Conclusions Our meta-analysis suggests that the CYP2C19 PMs genotypes most likely contributes to cancer susceptibility, particularly in the Asian populations. PMID:24015291

The relationship between urban environment and the inflammatory bowel diseases: a systematic review and meta-analysis.

PubMed

Soon, Ing Shian; Molodecky, Natalie A; Rabi, Doreen M; Ghali, William A; Barkema, Herman W; Kaplan, Gilaad G

2012-05-24

The objective of this study was to conduct a systematic review with meta-analysis of studies assessing the association between living in an urban environment and the development of the Crohn's disease (CD) or ulcerative colitis (UC). A systematic literature search of MEDLINE (1950-Oct. 2009) and EMBASE (1980-Oct. 2009) was conducted to identify studies investigating the relationship between urban environment and IBD. Cohort and case-control studies were analyzed using incidence rate ratio (IRR) or odds ratio (OR) with 95 % confidence intervals (CIs), respectively. Stratified and sensitivity analyses were performed to explore heterogeneity between studies and assess effects of study quality. The search strategy retrieved 6940 unique citations and 40 studies were selected for inclusion. Of these, 25 investigated the relationship between urban environment and UC and 30 investigated this relationship with CD. Included in our analysis were 7 case-control UC studies, 9 case-control CD studies, 18 cohort UC studies and 21 cohort CD studies. Based on a random effects model, the pooled IRRs for urban compared to rural environment for UC and CD studies were 1.17 (1.03, 1.32) and 1.42 (1.26, 1.60), respectively. These associations persisted across multiple stratified and sensitivity analyses exploring clinical and study quality factors. Heterogeneity was observed in the cohort studies for both UC and CD, whereas statistically significant heterogeneity was not observed for the case-control studies. A positive association between urban environment and both CD and UC was found. Heterogeneity may be explained by differences in study design and quality factors.

Structural Design and Analysis of the Upper Pressure Shell Section of a Composite Crew Module

NASA Technical Reports Server (NTRS)

Sleight, David W.; Paddock, David; Jeans, Jim W.; Hudeck, John D.

2008-01-01

This paper presents the results of the structural design and analysis of the upper pressure shell section of a carbon composite demonstration structure for the Composite Crew Module (CCM) Project. The project is managed by the NASA Engineering and Safety Center with participants from eight NASA Centers, the Air Force Research Laboratory, and multiple aerospace contractors including ATK/Swales, Northrop Grumman, Lockheed Martin, Collier Research Corporation, Genesis Engineering, and Janicki Industries. The paper discusses details of the upper pressure shell section design of the CCM and presents the structural analysis results using the HyperSizer structural sizing software and the MSC Nastran finite element analysis software. The HyperSizer results showed that the controlling load case driving most of the sizing in the upper pressure shell section was the internal pressure load case. The regions around the cutouts were controlled by internal pressure and the main parachute load cases. The global finite element analysis results showed that the majority of the elements of the CCM had a positive margin of safety with the exception of a few hot spots around the cutouts. These hot spots are currently being investigated with a more detailed analysis. Local finite element models of the Low Impact Docking System (LIDS) interface ring and the forward bay gussets with greater mesh fidelity were created for local sizing and analysis. The sizing of the LIDS interface ring was driven by the drogue parachute loads, Trans-Lunar Insertion (TLI) loads, and internal pressure. The drogue parachute loads controlled the sizing of the gusset cap on the drogue gusset and TLI loads controlled the sizing of the other five gusset caps. The main parachute loads controlled the sizing of the lower ends of the gusset caps on the main parachute fittings. The results showed that the gusset web/pressure shell and gusset web/gusset cap interfaces bonded using Pi-preform joints had local hot spots in the Pi-preform termination regions. These regions require a detailed three-dimensional analysis, which is currently being performed, to accurately address the load distribution near the Pi-preform termination in the upper and lower gusset caps.

[Epigenetic research of cognitive deficit in schizophrenia: some methodological considerations].

PubMed

Lezheiko, T V; Alfimova, M V

To highlights the problems of assessing cognitive deficits in schizophrenia, relevant to the epigenetic, as well as a wide range of other approaches to the search for biological bases of cognition. The literature on the weaknesses in the evaluation of cognitive functions in patients with schizophrenia are summarized and discussed. The analysis is illustrated by our experience in developing a cognitive battery and a sample to examine relationships between DNA methylation in blood cells and cognitive deficits in schizophrenia. It has been shown that to assess cognitive deficits in patients and to reduce the influence of confounders in epigenetic analysis it is necessary (1) to use a battery with the existing co-normative data in the target population, which allows to evaluate representativeness of control and patients included in the study sample, (2) to verify the theoretically driven battery structure using normative population and a cohort of patients, (3) to balance groups of cases and controls on the number, age and sex, for which an individual matching of cases and controls is best suited, (4) to conduct an additional statistical analysis controlling for education and smoking.

CFORM- LINEAR CONTROL SYSTEM DESIGN AND ANALYSIS: CLOSED FORM SOLUTION AND TRANSIENT RESPONSE OF THE LINEAR DIFFERENTIAL EQUATION

NASA Technical Reports Server (NTRS)

Jamison, J. W.

1994-01-01

CFORM was developed by the Kennedy Space Center Robotics Lab to assist in linear control system design and analysis using closed form and transient response mechanisms. The program computes the closed form solution and transient response of a linear (constant coefficient) differential equation. CFORM allows a choice of three input functions: the Unit Step (a unit change in displacement); the Ramp function (step velocity); and the Parabolic function (step acceleration). It is only accurate in cases where the differential equation has distinct roots, and does not handle the case for roots at the origin (s=0). Initial conditions must be zero. Differential equations may be input to CFORM in two forms - polynomial and product of factors. In some linear control analyses, it may be more appropriate to use a related program, Linear Control System Design and Analysis (KSC-11376), which uses root locus and frequency response methods. CFORM was written in VAX FORTRAN for a VAX 11/780 under VAX VMS 4.7. It has a central memory requirement of 30K. CFORM was developed in 1987.

Factors associated with adult poisoning in northern Malaysia: a case-control study.

PubMed

Fathelrahman, A I; Ab Rahman, A F; Zain, Z Mohd; Tengku, M A

2006-04-01

Data on adult risk factors associated with drug or chemical poisonings in Malaysia are scarce. The objective of the study was to identify possible risk factors associated with adult admissions to the Penang General Hospital (PGH) due to chemical poisoning and/or drug overdose. The present study was a case-control study, conducted over 18 weeks. One hundred acutely poisoned adult patients admitted to PGH during the period from September 2003 to February 2004 were considered as cases. Two hundred patients admitted to the same medical wards for other illnesses, during the same period, were matched for age and gender with the poisoned cases and thus selected as controls. McNemar test and binary logistic were used for univariate analysis and logistic regression analysis for multivariate analyses. The odds ratio (OR) and its 95% confidence interval (95% CI) were calculated for each predictor variable. Positive histories of psychiatric illness and previous poisoning, problems in boy/girl friend relationships, family problems, marital problems, Indian ethnicity, Chinese ethnicity, living in rented houses and living in a household with less than five people were significant risk factors associated with adult admissions due to poisoning.

[Association between hip fractures and risk factors for osteoporosis. Multivariate analysis].

PubMed

Masoni, Ana; Morosano, Mario; Tomat, María Florencia; Pezzotto, Stella M; Sánchez, Ariel

2007-01-01

In this observational, case-control study, 376 inpatients were evaluated in order to determine the association of risk factors (RF) and hip fracture; 151 patients had osteoporotic hip fracture (cases); the remaining were controls. Data were obtained from medical charts, and through a standardized questionnaire about RF. Mean age of the sample (+/- SD) was 80.6 +/- 8.1 years, without statistically significant difference between cases and controls; the female:male ratio was 3:1 in both groups. Fractured women were older than men (82.5 +/- 8.1 vs. 79.7 +/- 7.2 years, respectively; p < 0.01). Physical activity, intake of alcohol and tobacco, and sun exposure were low in all patients. Falls among cases happened predominantly at home (p < 0.001). Among female cases, time spent in household duties was a RF (p = 0.007), which was absent in males. In multivariate analysis, the following RF were significantly more frequent: Cognitive impairment (p = 0.001), and previous falls (p < 0.0001); whereas the following protective factors were significantly different from controls: Calcium intake during youth (p < 0.0001), current calcium intake (p < 0.0001), and mechanical aid for walking (p < 0.0001). Evaluation of RF and protective factors may contribute to diminish the probability of hip fracture, through a modification of personal habits, and measures to prevent falls among elderly adults. Present information can help to develop local and national population-based strategies to diminish the burden of hip fractures for the health system.

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.

Aircraft Loss-of-Control Accident Analysis

NASA Technical Reports Server (NTRS)

Belcastro, Christine M.; Foster, John V.

2010-01-01

Loss of control remains one of the largest contributors to fatal aircraft accidents worldwide. Aircraft loss-of-control accidents are complex in that they can result from numerous causal and contributing factors acting alone or (more often) in combination. Hence, there is no single intervention strategy to prevent these accidents. To gain a better understanding into aircraft loss-of-control events and possible intervention strategies, this paper presents a detailed analysis of loss-of-control accident data (predominantly from Part 121), including worst case combinations of causal and contributing factors and their sequencing. Future potential risks are also considered.

Introduction to Command, Control and Communications (C3) Through Comparative Case Analysis

DTIC Science & Technology

1990-03-01

enhancing the process of learning from experience. Case study allows the student to apply concepts , theories, and techniques to an actual incident within...part of the thesis describes selected principles and concepts of 33 related to cormruication management, interoperability, command structure and...The solutions to the cases require applying the principles and concepts presented in the first rart. The four cases are: (1) the Iran hostage rescue

Meta-analysis of 74,046 individuals identifies 11 new susceptibility loci for Alzheimer’s disease

PubMed Central

Lambert, Jean-Charles; Ibrahim-Verbaas, Carla A; Harold, Denise; Naj, Adam C; Sims, Rebecca; Bellenguez, Céline; Jun, Gyungah; DeStefano, Anita L; Bis, Joshua C; Beecham, Gary W; Grenier-Boley, Benjamin; Russo, Giancarlo; Thornton-Wells, Tricia A; Jones, Nicola; Smith, Albert V; Chouraki, Vincent; Thomas, Charlene; Ikram, M Arfan; Zelenika, Diana; Vardarajan, Badri N; Kamatani, Yoichiro; Lin, Chiao-Feng; Gerrish, Amy; Schmidt, Helena; Kunkle, Brian; Dunstan, Melanie L; Ruiz, Agustin; Bihoreau, Marie-Thérèse; Choi, Seung-Hoan; Reitz, Christiane; Pasquier, Florence; Hollingworth, Paul; Ramirez, Alfredo; Hanon, Olivier; Fitzpatrick, Annette L; Buxbaum, Joseph D; Campion, Dominique; Crane, Paul K; Baldwin, Clinton; Becker, Tim; Gudnason, Vilmundur; Cruchaga, Carlos; Craig, David; Amin, Najaf; Berr, Claudine; Lopez, Oscar L; De Jager, Philip L; Deramecourt, Vincent; Johnston, Janet A; Evans, Denis; Lovestone, Simon; Letenneur, Luc; Morón, Francisco J; Rubinsztein, David C; Eiriksdottir, Gudny; Sleegers, Kristel; Goate, Alison M; Fiévet, Nathalie; Huentelman, Matthew J; Gill, Michael; Brown, Kristelle; Kamboh, M Ilyas; Keller, Lina; Barberger-Gateau, Pascale; McGuinness, Bernadette; Larson, Eric B; Green, Robert; Myers, Amanda J; Dufouil, Carole; Todd, Stephen; Wallon, David; Love, Seth; Rogaeva, Ekaterina; Gallacher, John; St George-Hyslop, Peter; Clarimon, Jordi; Lleo, Alberto; Bayer, Anthony; Tsuang, Debby W; Yu, Lei; Tsolaki, Magda; Bossù, Paola; Spalletta, Gianfranco; Proitsi, Petroula; Collinge, John; Sorbi, Sandro; Sanchez-Garcia, Florentino; Fox, Nick C; Hardy, John; Deniz Naranjo, Maria Candida; Bosco, Paolo; Clarke, Robert; Brayne, Carol; Galimberti, Daniela; Mancuso, Michelangelo; Matthews, Fiona; Moebus, Susanne; Mecocci, Patrizia; Zompo, Maria Del; Maier, Wolfgang; Hampel, Harald; Pilotto, Alberto; Bullido, Maria; Panza, Francesco; Caffarra, Paolo; Nacmias, Benedetta; Gilbert, John R; Mayhaus, Manuel; Lannfelt, Lars; Hakonarson, Hakon; Pichler, Sabrina; Carrasquillo, Minerva M; Ingelsson, Martin; Beekly, Duane; Alvarez, Victoria; Zou, Fanggeng; Valladares, Otto; Younkin, Steven G; Coto, Eliecer; Hamilton-Nelson, Kara L; Gu, Wei; Razquin, Cristina; Pastor, Pau; Mateo, Ignacio; Owen, Michael J; Faber, Kelley M; Jonsson, Palmi V; Combarros, Onofre; O’Donovan, Michael C; Cantwell, Laura B; Soininen, Hilkka; Blacker, Deborah; Mead, Simon; Mosley, Thomas H; Bennett, David A; Harris, Tamara B; Fratiglioni, Laura; Holmes, Clive; de Bruijn, Renee F A G; Passmore, Peter; Montine, Thomas J; Bettens, Karolien; Rotter, Jerome I; Brice, Alexis; Morgan, Kevin; Foroud, Tatiana M; Kukull, Walter A; Hannequin, Didier; Powell, John F; Nalls, Michael A; Ritchie, Karen; Lunetta, Kathryn L; Kauwe, John S K; Boerwinkle, Eric; Riemenschneider, Matthias; Boada, Mercè; Hiltunen, Mikko; Martin, Eden R; Schmidt, Reinhold; Rujescu, Dan; Wang, Li-san; Dartigues, Jean-François; Mayeux, Richard; Tzourio, Christophe; Hofman, Albert; Nöthen, Markus M; Graff, Caroline; Psaty, Bruce M; Jones, Lesley; Haines, Jonathan L; Holmans, Peter A; Lathrop, Mark; Pericak-Vance, Margaret A; Launer, Lenore J; Farrer, Lindsay A; van Duijn, Cornelia M; Van Broeckhoven, Christine; Moskvina, Valentina; Seshadri, Sudha; Williams, Julie; Schellenberg, Gerard D; Amouyel, Philippe

2013-01-01

Eleven susceptibility loci for late-onset Alzheimer’s disease (LOAD) were identified by previous studies; however, a large portion of the genetic risk for this disease remains unexplained. We conducted a large, two-stage meta-analysis of genome-wide association studies (GWAS) in individuals of European ancestry. In stage 1, we used genotyped and imputed data (7,055,881 SNPs) to perform meta-analysis on 4 previously published GWAS data sets consisting of 17,008 Alzheimer’s disease cases and 37,154 controls. In stage 2,11,632 SNPs were genotyped and tested for association in an independent set of 8,572 Alzheimer’s disease cases and 11,312 controls. In addition to the APOE locus (encoding apolipoprotein E), 19 loci reached genome-wide significance (P < 5 × 10−8) in the combined stage 1 and stage 2 analysis, of which 11 are newly associated with Alzheimer’s disease. PMID:24162737

TERT rs2736098 polymorphism and cancer risk: results of a meta-analysis.

PubMed

Qi, Hao-Yu; Zou, Peng; Zhao, Lin; Zhu, Jue; Gu, Ai-Hua

2012-01-01

Several studies have demonstrated associations between the TERT rs2736098 single nucleotide polymorphisms (SNPs) and susceptibility to cancer development. However, there are conflicting results. A systematic meta-analysis was therefore performed to establish the cancer risk associated with the polymorphism. In this meta-analysis, a total of 6 case-control studies, including 5,567 cases and 6,191 controls, were included. Crude odds ratios with 95% confidence intervals were used to assess the strength of associations in several genetic models. Our results showed no association reaching the level of statistical significance for overall risk. Interestingly, in the stratified analyses (subdivided by ethnicity), significantly increased risks were found in the Asian subgroup which indicates the TERT rs2736098 polymorphism may have controversial involvement in cancer susceptibility. Overall, this meta-analysis indicates that the TERT rs2736098 polymorphism may have little involvement in cancer susceptibility.

A case study of the sensitivity of forecast skill to data and data analysis techniques

NASA Technical Reports Server (NTRS)

Baker, W. E.; Atlas, R.; Halem, M.; Susskind, J.

1983-01-01

A series of experiments have been conducted to examine the sensitivity of forecast skill to various data and data analysis techniques for the 0000 GMT case of January 21, 1979. These include the individual components of the FGGE observing system, the temperatures obtained with different satellite retrieval methods, and the method of vertical interpolation between the mandatory pressure analysis levels and the model sigma levels. It is found that NESS TIROS-N infrared retrievals seriously degrade a rawinsonde-only analysis over land, resulting in a poorer forecast over North America. Less degradation in the 72-hr forecast skill at sea level and some improvement at 500 mb is noted, relative to the control with TIROS-N retrievals produced with a physical inversion method which utilizes a 6-hr forecast first guess. NESS VTPR oceanic retrievals lead to an improved forecast over North America when added to the control.

Gastric cancer in Zambian adults: a prospective case-control study that assessed dietary intake and antioxidant status by using urinary isoprostane excretion.

PubMed

Asombang, Akwi W; Kayamba, Violet; Mwanza-Lisulo, Mpala; Colditz, Graham; Mudenda, Victor; Yarasheski, Kevin; Chott, Robert; Rubin, Deborah C; Gyawali, C Prakash; Sinkala, Edford; Mwanamakondo, Stayner; Anderson-Spearie, Catherine; Kelly, Paul

2013-05-01

Gastric cancer is increasingly recognized in Zambia. Although nutritional factors contribute to gastric cancer risk, their effect in Zambia is unknown. The objective was to investigate the association between intake of dietary antioxidants, urinary 8-iso prostaglandin F2α (8-iso PGF2α) as a marker of oxidative stress, and gastric cancer. This was a case-control study at the University Teaching Hospital in Zambia. Gastric cancer cases were compared with age- and sex-matched controls. Urine 8-iso PGF2α was measured primarily by ELISA, and by gas chromatography-mass spectrometry in a subset, expressed as a ratio to creatinine. Blood was collected for Helicobacter pylori, HIV serology, gastrin-17, and pepsinogen 1 and 2 concentrations. Clinical and dietary data were collected by using questionnaires. Food items were broadly classified into 7 major categories (fruit, vegetables, fish, meat, insects, cereals, and starches). Fifty cases with gastric cancer (mean age: 61 y; n = 31 males) and 90 controls (mean age: 54 y; n = 41 males) were enrolled. Median urinary 8-iso PGF2α excretion was higher in cases (0.014; IQR: 0.008-0.021) than in controls (0.011; IQR: 0.006-0.018; P = 0.039). On univariate analysis, habitual fruit intake was lower in cases than in controls during the dry season (P = 0.02). On multivariate analysis, smoking (OR: 7.22; IQR: 1.38-37.9) and gastric atrophy (OR: 2.43; IQR: 1.12-5.13) were independently associated with cancer, and higher fruit intake was protective (OR: 0.44; IQR: 0.20-0.95). Isoprostane excretion was inversely correlated with total fruit intake (ρ = -0.23; n = 140; P = 0.006). Urinary 8-iso PGF2α excretion was associated with the risk of gastric cancer, as were smoking and gastric atrophy, but increased fruit intake conferred protection. This trial was registered at www.pactr.org as ISRCTN52971746.

Sleep in patients with remitted bipolar disorders: a meta-analysis of actigraphy studies.

PubMed

Geoffroy, P A; Scott, J; Boudebesse, C; Lajnef, M; Henry, C; Leboyer, M; Bellivier, F; Etain, B

2015-02-01

Sleep dysregulation is highly prevalent in bipolar disorders (BDs), with previous actigraphic studies demonstrating sleep abnormalities during depressive, manic, and interepisode periods. We undertook a meta-analysis of published actigraphy studies to identify whether any abnormalities in the reported sleep profiles of remitted BD cases differ from controls. A systematic review identified independent studies that were eligible for inclusion in a random effects meta-analysis. Effect sizes for actigraphy parameters were expressed as standardized mean differences (SMD) with 95% confidence intervals (95% CI). Nine of 248 identified studies met eligibility criteria. Compared with controls (N=210), remitted BD cases (N=202) showed significant differences in SMD for sleep latency (0.51 [0.28-0.73]), sleep duration (0.57 [0.30-0.84]), wake after sleep onset (WASO) (0.28 [0.06-0.50]) and sleep efficiency (-0.38 [-0.70-0.07]). Moderate heterogeneity was identified for sleep duration (I2=44%) and sleep efficiency (I2=44%). Post hoc meta-regression analyses demonstrated that larger SMD for sleep duration were identified for studies with a greater age difference between BD cases and controls (β=0.22; P=0.03) and non-significantly lower levels of residual depressive symptoms in BD cases (β=-0.13; P=0.07). This meta-analysis of sleep in remitted bipolar disorder highlights disturbances in several sleep parameters. Future actigraphy studies should pay attention to age matching and levels of residual depressive symptoms. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Analysis of potential protein-modifying variants in 9000 endometriosis patients and 150000 controls of European ancestry.

PubMed

Sapkota, Yadav; Vivo, Immaculata De; Steinthorsdottir, Valgerdur; Fassbender, Amelie; Bowdler, Lisa; Buring, Julie E; Edwards, Todd L; Jones, Sarah; O, Dorien; Peterse, Daniëlle; Rexrode, Kathryn M; Ridker, Paul M; Schork, Andrew J; Thorleifsson, Gudmar; Wallace, Leanne M; Kraft, Peter; Morris, Andrew P; Nyholt, Dale R; Edwards, Digna R Velez; Nyegaard, Mette; D'Hooghe, Thomas; Chasman, Daniel I; Stefansson, Kari; Missmer, Stacey A; Montgomery, Grant W

2017-09-12

Genome-wide association (GWA) studies have identified 19 independent common risk loci for endometriosis. Most of the GWA variants are non-coding and the genes responsible for the association signals have not been identified. Herein, we aimed to assess the potential role of protein-modifying variants in endometriosis using exome-array genotyping in 7164 cases and 21005 controls, and a replication set of 1840 cases and 129016 controls of European ancestry. Results in the discovery sample identified significant evidence for association with coding variants in single-variant (rs1801232-CUBN) and gene-level (CIITA and PARP4) meta-analyses, but these did not survive replication. In the combined analysis, there was genome-wide significant evidence for rs13394619 (P = 2.3 × 10 -9 ) in GREB1 at 2p25.1 - a locus previously identified in a GWA meta-analysis of European and Japanese samples. Despite sufficient power, our results did not identify any protein-modifying variants (MAF > 0.01) with moderate or large effect sizes in endometriosis, although these variants may exist in non-European populations or in high-risk families. The results suggest continued discovery efforts should focus on genotyping large numbers of surgically-confirmed endometriosis cases and controls, and/or sequencing high-risk families to identify novel rare variants to provide greater insights into the molecular pathogenesis of the disease.

Retinal Nerve Fiber Layer Thickness Changes in the Pseudoexfoliation Syndrome: A Meta-Analysis of Case-Control Studies.

PubMed

Yu, Ji-Guo; Huang, Qing; Zhou, Xiao-Fang; Ding, Yi; Li, Jing; Xiang, Yi

2018-01-01

To evaluate and compare changes in retinal nerve fiber layer (RNFL) thickness in patients with the pseudoexfoliation syndrome (PXS) and healthy controls. Case-control studies were selected through an electronic search of the Cochrane Controlled Trials Register, PubMed, and Embase. Results were reviewed to ensure that the included studies met prespecified inclusion/exclusion criteria, and the quality of each study was assessed using the Newcastle-Ottawa Scale. All included studies measured average and 4-quadrant (temporal, superior, nasal, and inferior) RNFL thickness using optical coherence tomography (OCT). For the continuous outcomes, we calculated the weighted mean difference (WMD) and 95% confidence intervals (CIs). Eight case-control studies were included in this meta-analysis involving 225 eyes of PXS patients and 208 eyes of healthy controls in total. Statistical analysis revealed that the average RNFL thickness in PXS patients was significantly reduced compared to healthy controls (WMD = -6.91, 95% CI: -9.99 to -3.82, p < 0.0001). Additionally, differences in RNFL thickness in the superior quadrant (WMD = -10.68, 95% CI: -16.40 to -4.95, p = 0.0003), inferior quadrant (WMD = -8.20, 95% CI: -10.85 to -5.55, p < 0.00001), nasal quadrant (WMD = -3.05, 95% CI: -5.21 to -0.90, p = 0.005), and temporal quadrant (WMD = -6.39, 95% CI: -9.98 to -2.80, p = 0.0005) were all significant between the two groups. These results suggest that it is important to evaluate RNFL thickness and the optic nerve head through OCT in patients with PXS in order to determine early glaucomatous damage and start timely intervention prior to visual field loss. © 2017 S. Karger AG, Basel.

Sympathetic skin response in multiple sclerosis: a meta-analysis of case-control studies.

PubMed

Margaritella, Nicolò; Mendozzi, Laura; Garegnani, Massimo; Gilardi, Elisabetta; Nemni, Raffaello; Pugnetti, Luigi

2018-01-01

The usefulness of sympathetic skin responses (SSR) in multiple sclerosis (MS) has been advocated by several studies in the last 20 years; however, due to a great heterogeneity of findings, a comprehensive meta-analysis of case-control studies is in order to pinpoint consistencies and investigate the causes of discrepancies. We searched MEDLINE, EMBASE and Cochrane databases for case-control studies comparing SSR absence frequency and latency between patients with MS and healthy controls. Thirteen eligible studies including 415 MS patients and 331 healthy controls were identified. The pooled analysis showed that SSR can be always obtained in healthy controls while 34% of patients had absent SSRs in at least one limb (95% CI 22-47%; p < 0.0001) but with considerable heterogeneity across studies (I 2  = 90.3%). Patients' age explained 22% of the overall variability and positive correlations were found with Expanded Disability Status Scale and disease duration. The pooled mean difference of SSR latency showed a significant increase in patients on both upper (193 ms; 95% CI 120-270 ms) and lower (350 ms; 95% CI 190-510 ms) extremities. We tested the discriminatory value of SSR latency thresholds defined as the 95% confidence interval (CI) upper bound of the healthy controls, and validated the results on a new dataset. The lower limb threshold of 1.964 s produces the best results in terms of sensitivity 0.86, specificity 0.67, positive predicted value 0.75 and negative predicted value 0.80. Despite a considerable heterogeneity of findings, there is evidence that SSR is a useful tool in MS.

Effectiveness of Riluzole as a pharmacotherapeutic treatment option for early cervical myelopathy: a double-blinded, placebo-controlled randomised controlled trial.

PubMed

Rajasekaran, S; Aiyer, Siddharth N; Shetty, Ajoy Prasad; Kanna, Rishi Mugesh; Maheswaran, Anupama; Shetty, Janardhan Yerram

2016-06-01

To evaluate the effectiveness of Riluzole as a pharmacotherapeutic treatment option for early cervical myelopathy using clinical parameters and DTI analysis. Early cervical myelopathy cases with MJOA scores ≥13, were recruited for the double-blinded, placebo-controlled randomised control trial. Thirty cases with fifteen cases each in the test and placebo group were studied. Analysis was done using diffusion tensor imaging (DTI) and clinical evaluation, pre- and post-institution of sodium channel blocker Riluzole for a period of 1 month (50 mg twice daily). Placebo group was treated with Vitamin B complex tablets. Diffusion co-efficient fractional anisotrophy (FA), apparent diffusion co-efficient (ADC), volume ratio (VR), relative anisotrophy (RA) and Eigen vectors were calculated. Outcomes analysis was based on clinical scores of MJOA, Nurick grading, SF-12, NDI, and statistical analysis of DTI datametrics. The mean MJOA score was 15.6 (13-17) with no significant change in the test and control groups. The mean ADC, FA values were 1533.36 (1238-1779) and 494.36 (364-628) and changed to 1531.57 (1312-2091) and 484.86 (294-597), respectively, in the Riluzole group. However, the changes in the values of ADC, FA, and other co-efficients including VR, RA and eigenvectors in the two groups were not statistically significant. The functional scores in the SF-12 and NDI questionnaires did not change significantly. Our study did not show a significant change in the clinical outcome and DTI Indices with the use of Riluzole as a standalone pharmacotherapeutic agent for early cervical myelopathy. More studies may be needed to confirm the usefulness of Riluzole as a treatment option for cervical myelopathy.

VIM-positive Pseudomonas aeruginosa in a large tertiary care hospital: matched case-control studies and a network analysis.

PubMed

Voor In 't Holt, Anne F; Severin, Juliëtte A; Hagenaars, Margot B H; de Goeij, Inge; Gommers, Diederik; Vos, Margreet C

2018-01-01

Emergence of multidrug-resistant Pseudomonas aeruginosa is of global concern. We aimed to identify epidemiological relationships, the most common way of transmission, and risk factors for presence of Verona Integron-encoded Metallo-β-lactamase (VIM)-positive P. aeruginosa (VIM-PA). We conducted a network analysis and matched case-control studies (1:2:2). Controls were hospital-based and matched with cases for ward, day of admission (control group 1 and 2) and time between admission and the identification of VIM-PA (control group 1). The network was visualized using Cytoscape, and risk factors were determined using conditional logistic regression. Between August 2003 and April 2015, 144 case patients and 576 control patients were recruited. We identified 307 relationships in 114 out of these 144 patients, with most relationships (84.7%) identified at the same department < 3 months after a previous case patient was discharged. In the multivariable model, having undergone ≥1 gastroscopy (odds ratio [OR] = 4.40, 95% confidence interval [CI] = 2.00 to 9.65 and OR = 2.47; 95% CI = 1.12 to 5.49), > 10 day use of selective digestive tract decontamination (SDD) (OR = 2.97; 95% CI = 1.02 to 8.68 and OR = 4.61; 95% CI = 1.22 to 17.37), and use of quinolones (OR = 3.29; 95% CI = 1.34 to 8.10 and OR = 3.95; 95% CI = 1.13 to 13.83 and OR = 4.47; 95% CI = 1.75 to 11.43) were identified as risk factors when using both control groups. The network analysis indicated that the majority of transmissions occurred on the wards, but through unidentified and presumably persistent sources, which are most likely in the innate hospital environment. Previous use of certain antibiotic regimens made patients prone to VIM-PA carriage. Additionally, gastroscopy could be considered as a high-risk procedure in patients with risk factors. Our results add to the growing body of evidence that infection control measures targeting VIM-PA should be focused on reducing antibiotics and eliminating sources in the environment.

Probabilistic Parameter Uncertainty Analysis of Single Input Single Output Control Systems

NASA Technical Reports Server (NTRS)

Smith, Brett A.; Kenny, Sean P.; Crespo, Luis G.

2005-01-01

The current standards for handling uncertainty in control systems use interval bounds for definition of the uncertain parameters. This approach gives no information about the likelihood of system performance, but simply gives the response bounds. When used in design, current methods of m-analysis and can lead to overly conservative controller design. With these methods, worst case conditions are weighted equally with the most likely conditions. This research explores a unique approach for probabilistic analysis of control systems. Current reliability methods are examined showing the strong areas of each in handling probability. A hybrid method is developed using these reliability tools for efficiently propagating probabilistic uncertainty through classical control analysis problems. The method developed is applied to classical response analysis as well as analysis methods that explore the effects of the uncertain parameters on stability and performance metrics. The benefits of using this hybrid approach for calculating the mean and variance of responses cumulative distribution functions are shown. Results of the probabilistic analysis of a missile pitch control system, and a non-collocated mass spring system, show the added information provided by this hybrid analysis.

Comparison of extended colectomy and limited resection in patients with Lynch syndrome.

PubMed

Natarajan, Nagendra; Watson, Patrice; Silva-Lopez, Edibaldo; Lynch, Henry T

2010-01-01

The purpose of the study was to determine the advantages and disadvantages of prophylactic/extended colectomy (subtotal colectomy) in patients with Lynch syndrome who manifest colorectal cancer. A retrospective cohort using Creighton University's hereditary cancer database was used to identify cases and controls. Cases are patients who underwent subtotal colectomy, either with no colorectal cancer diagnosis (prophylactic) or at diagnosis of first colorectal cancer; controls for these 2 types of cases were, respectively, patients who underwent no colon surgery or those having limited resection at time of diagnosis of first colorectal cancer. The Kaplan-Meier and proportional hazard regression models from the Statistical Analysis Software program was used to calculate the difference in survival, time to subsequent colorectal cancer, and subsequent abdominal surgery between cases and controls. The event-free survival of our study did not reach 50%, so we used the event-free survival at 5 years as our parameter to compare the 2 groups. The event-free survival for subsequent colorectal cancer, subsequent abdominal surgery, and death was 94%, 84%, and 93%, respectively, for cases and 74%, 63%, and 88%, respectively, for controls. Times to subsequent colorectal cancer and subsequent abdominal surgery were significantly shorter in the control group (P < .006 and P < .04, respectively). No significant difference was identified with respect to survival time between the cases and controls. Even though no survival benefit was identified between the cases and controls the increased incidence of metachronous colorectal cancer and increased abdominal surgeries among controls warrant the recommendation of subtotal colectomy in patients with Lynch syndrome.

Risk factors for Mycobacterium ulcerans infection (Buruli Ulcer) in Togo ─ a case-control study in Zio and Yoto districts of the maritime region.

PubMed

Maman, Issaka; Tchacondo, Tchadjobo; Kere, Abiba Banla; Piten, Ebekalisai; Beissner, Marcus; Kobara, Yiragnima; Kossi, Komlan; Badziklou, Kossi; Wiedemann, Franz Xaver; Amekuse, Komi; Bretzel, Gisela; Karou, Damintoti Simplice

2018-01-19

Buruli ulcer (BU) is a neglected mycobacterial skin infection caused by Mycobacterium ulcerans. This disease mostly affects poor rural populations, especially in areas with low hygiene standards and sanitation coverage. The objective of this study was to identify these risk factors in the districts of Zio and Yoto of the Maritime Region in Togo. We conducted a case-control study in Zio and Yoto, two districts proved BU endemic from November 2014 to May 2015. BU cases were diagnosed according to the WHO clinical case definition at the Centre Hospitalier Régional de Tsévié (CHR Tsévié) and confirmed by Ziehl-Neelsen (ZN) microscopy and IS2404 polymerase chain reaction (PCR). For each case, up to two controls matched by sex and place of residence were recruited. Socio-demographic, environmental or behavioral data were collected and conditional logistic regression analysis was used to identify and compare risk factors between BU cases and controls. A total of 83 cases and 128 controls were enrolled. The median age was 15 years (range 3-65 years). Multivariate conditional logistic regression analysis after adjustment for potential confounders identified age (< 10 years (OR =11.48, 95% CI = 3.72-35.43) and 10-14 years (OR = 3.63, 95% CI = 1.22-10.83)), receiving insect bites near a river (OR = 7.8, 95% CI = 1.48-41.21) and bathing with water from open borehole (OR = 5.77, (1.11-29.27)) as independent predictors of acquiring BU infection. This study identified age, bathing with water from open borehole and receiving insect bites near a river as potential risk of acquiring BU infection in Zio and Yoto districts of the Maritime Region in south Togo.

Space-Time Analysis of Testicular Cancer Clusters Using Residential Histories: A Case-Control Study in Denmark

PubMed Central

Sloan, Chantel D.; Nordsborg, Rikke B.; Jacquez, Geoffrey M.; Raaschou-Nielsen, Ole; Meliker, Jaymie R.

2015-01-01

Though the etiology is largely unknown, testicular cancer incidence has seen recent significant increases in northern Europe and throughout many Western regions. The most common cancer in males under age 40, age period cohort models have posited exposures in the in utero environment or in early childhood as possible causes of increased risk of testicular cancer. Some of these factors may be tied to geography through being associated with behavioral, cultural, sociodemographic or built environment characteristics. If so, this could result in detectable geographic clusters of cases that could lead to hypotheses regarding environmental targets for intervention. Given a latency period between exposure to an environmental carcinogen and testicular cancer diagnosis, mobility histories are beneficial for spatial cluster analyses. Nearest-neighbor based Q-statistics allow for the incorporation of changes in residency in spatial disease cluster detection. Using these methods, a space-time cluster analysis was conducted on a population-wide case-control population selected from the Danish Cancer Registry with mobility histories since 1971 extracted from the Danish Civil Registration System. Cases (N=3297) were diagnosed between 1991 and 2003, and two sets of controls (N=3297 for each set) matched on sex and date of birth were included in the study. We also examined spatial patterns in maternal residential history for those cases and controls born in 1971 or later (N= 589 case-control pairs). Several small clusters were detected when aligning individuals by year prior to diagnosis, age at diagnosis and calendar year of diagnosis. However, the largest of these clusters contained only 2 statistically significant individuals at their center, and were not replicated in SaTScan spatial-only analyses which are less susceptible to multiple testing bias. We found little evidence of local clusters in residential histories of testicular cancer cases in this Danish population. PMID:25756204

Space-time analysis of testicular cancer clusters using residential histories: a case-control study in Denmark.

PubMed

Sloan, Chantel D; Nordsborg, Rikke B; Jacquez, Geoffrey M; Raaschou-Nielsen, Ole; Meliker, Jaymie R

2015-01-01

Though the etiology is largely unknown, testicular cancer incidence has seen recent significant increases in northern Europe and throughout many Western regions. The most common cancer in males under age 40, age period cohort models have posited exposures in the in utero environment or in early childhood as possible causes of increased risk of testicular cancer. Some of these factors may be tied to geography through being associated with behavioral, cultural, sociodemographic or built environment characteristics. If so, this could result in detectable geographic clusters of cases that could lead to hypotheses regarding environmental targets for intervention. Given a latency period between exposure to an environmental carcinogen and testicular cancer diagnosis, mobility histories are beneficial for spatial cluster analyses. Nearest-neighbor based Q-statistics allow for the incorporation of changes in residency in spatial disease cluster detection. Using these methods, a space-time cluster analysis was conducted on a population-wide case-control population selected from the Danish Cancer Registry with mobility histories since 1971 extracted from the Danish Civil Registration System. Cases (N=3297) were diagnosed between 1991 and 2003, and two sets of controls (N=3297 for each set) matched on sex and date of birth were included in the study. We also examined spatial patterns in maternal residential history for those cases and controls born in 1971 or later (N= 589 case-control pairs). Several small clusters were detected when aligning individuals by year prior to diagnosis, age at diagnosis and calendar year of diagnosis. However, the largest of these clusters contained only 2 statistically significant individuals at their center, and were not replicated in SaTScan spatial-only analyses which are less susceptible to multiple testing bias. We found little evidence of local clusters in residential histories of testicular cancer cases in this Danish population.

Improving power and robustness for detecting genetic association with extreme-value sampling design.

PubMed

Chen, Hua Yun; Li, Mingyao

2011-12-01

Extreme-value sampling design that samples subjects with extremely large or small quantitative trait values is commonly used in genetic association studies. Samples in such designs are often treated as "cases" and "controls" and analyzed using logistic regression. Such a case-control analysis ignores the potential dose-response relationship between the quantitative trait and the underlying trait locus and thus may lead to loss of power in detecting genetic association. An alternative approach to analyzing such data is to model the dose-response relationship by a linear regression model. However, parameter estimation from this model can be biased, which may lead to inflated type I errors. We propose a robust and efficient approach that takes into consideration of both the biased sampling design and the potential dose-response relationship. Extensive simulations demonstrate that the proposed method is more powerful than the traditional logistic regression analysis and is more robust than the linear regression analysis. We applied our method to the analysis of a candidate gene association study on high-density lipoprotein cholesterol (HDL-C) which includes study subjects with extremely high or low HDL-C levels. Using our method, we identified several SNPs showing a stronger evidence of association with HDL-C than the traditional case-control logistic regression analysis. Our results suggest that it is important to appropriately model the quantitative traits and to adjust for the biased sampling when dose-response relationship exists in extreme-value sampling designs. © 2011 Wiley Periodicals, Inc.

Bayesian adjustment for measurement error in continuous exposures in an individually matched case-control study.

PubMed

Espino-Hernandez, Gabriela; Gustafson, Paul; Burstyn, Igor

2011-05-14

In epidemiological studies explanatory variables are frequently subject to measurement error. The aim of this paper is to develop a Bayesian method to correct for measurement error in multiple continuous exposures in individually matched case-control studies. This is a topic that has not been widely investigated. The new method is illustrated using data from an individually matched case-control study of the association between thyroid hormone levels during pregnancy and exposure to perfluorinated acids. The objective of the motivating study was to examine the risk of maternal hypothyroxinemia due to exposure to three perfluorinated acids measured on a continuous scale. Results from the proposed method are compared with those obtained from a naive analysis. Using a Bayesian approach, the developed method considers a classical measurement error model for the exposures, as well as the conditional logistic regression likelihood as the disease model, together with a random-effect exposure model. Proper and diffuse prior distributions are assigned, and results from a quality control experiment are used to estimate the perfluorinated acids' measurement error variability. As a result, posterior distributions and 95% credible intervals of the odds ratios are computed. A sensitivity analysis of method's performance in this particular application with different measurement error variability was performed. The proposed Bayesian method to correct for measurement error is feasible and can be implemented using statistical software. For the study on perfluorinated acids, a comparison of the inferences which are corrected for measurement error to those which ignore it indicates that little adjustment is manifested for the level of measurement error actually exhibited in the exposures. Nevertheless, a sensitivity analysis shows that more substantial adjustments arise if larger measurement errors are assumed. In individually matched case-control studies, the use of conditional logistic regression likelihood as a disease model in the presence of measurement error in multiple continuous exposures can be justified by having a random-effect exposure model. The proposed method can be successfully implemented in WinBUGS to correct individually matched case-control studies for several mismeasured continuous exposures under a classical measurement error model.

Risk factors for the development of colorectal carcinoma: A case control study from South India

PubMed Central

Iswarya, Santhana Krishnan; Premarajan, Kariyarath Cheriyath; Kar, Sitanshu Sekhar; Kumar, Sathasivam Suresh; Kate, Vikram

2016-01-01

AIM: To study the association of colorectal carcinoma (CRC) with diet, smoking, alcohol, physical activity, body mass index, family history and diabetes. METHODS: All consecutive patients with CRC confirmed by histopathology diagnosis were included. Age (± 5 years) and gender matched controls were selected among the patients admitted in surgery ward for various conditions without any co-existing malignancy. Food frequency questionnaire (FFQ) was developed and validated after pretesting by investigator trained in data collection techniques. Cases and controls were interviewed ensuring privacy, in similar interview setting, with same duration of time for both cases and controls without any leading question. Biological variables like family history of CRC in first degree relatives, history of diabetes mellitus; behavioral factors like tobacco use both smoking and smokeless form, alcohol consumption and physical activity were recorded. Dietary details were recorded using a FFQ consisting 29 food items with seven categories. Analysis was done using appropriate statistical methods. RESULTS: Ninety-four histopathologically confirmed cases of CRC and equal number of age and gender matched controls treated over a period of two years were studied. Age distribution, mean age, male to female ratio, education level and socioeconomic status were similar in cases and controls. Intake of food items was categorized into tertile due to skewed distribution of subjects as per recommended cut off for consumption of food item. On univariate analysis red meat [OR = 7.4 (2.935-18.732)], egg [OR = 5.1 (2.26-11.36)], fish, fried food and oil consumption were found to be risk factors for CRC. On multivariate analysis red meat consumption of more than 2-3 times a month (OR = 5.4; 95%CI: 1.55-19.05) and egg consumption of more than 2-3 times a week (OR = 3.67; 95%CI: 1.23-9.35) were found to be independent risk factors for the development of CRC. CONCLUSION: Egg and red meat consumption found to be independent risk factors for CRC. Smoking, alcohol, physical activity and family history were not associated with increased risk. PMID:26909135

Benzene Case Study Final Report - Second Prospective Report Study Science Advisory Board Review, July 2009

EPA Pesticide Factsheets

EPA developed a methodology for estimating the health benefits of benzene reductions and has applied it in a metropolitan-scale case study of the benefits of CAA controls on benzene emissions to accompany the main 812 analysis.

Draft Benzene Case Study Review - Second Prospective Report Study Science Advisory Board Review, March 2008

EPA Pesticide Factsheets

EPA developed a methodology for estimating the health benefits of benzene reductions and has applied it in a metropolitan-scale case study of the benefits of CAA controls on benzene emissions to accompany the main 812 analysis.

Pain Sensitivity Risk Factors for Chronic TMD: Descriptive Data and Empirically Identified Domains from the OPPERA Case Control Study

PubMed Central

Greenspan, Joel D.; Slade, Gary D.; Bair, Eric; Dubner, Ronald; Fillingim, Roger B.; Ohrbach, Richard; Knott, Charlie; Mulkey, Flora; Rothwell, Rebecca; Maixner, William

2011-01-01

Many studies report that people with temporomandibular disorders (TMD) are more sensitive to experimental pain stimuli than TMD-free controls. Such differences in sensitivity are observed in remote body sites as well as in the orofacial region, suggesting a generalized upregulation of nociceptive processing in TMD cases. This large case-control study of 185 adults with TMD and 1,633 TMD-free controls measured sensitivity to painful pressure, mechanical cutaneous, and heat stimuli, using multiple testing protocols. Based on an unprecedented 36 experimental pain measures, 28 showed statistically significantly greater pain sensitivity in TMD cases than controls. The largest effects were seen for pressure pain thresholds at multiple body sites and cutaneous mechanical pain threshold. The other mechanical cutaneous pain measures and many of the heat pain measures showed significant differences, but with lesser effect sizes. Principal component analysis (PCA) of the pain measures derived from 1,633 controls identified five components labeled: (1) heat pain ratings, (2) heat pain aftersensations and tolerance, (3) mechanical cutaneous pain sensitivity, (4) pressure pain thresholds, and (5) heat pain temporal summation. These results demonstrate that, compared to TMD-free controls, chronic TMD cases are more sensitive to many experimental noxious stimuli at extra-cranial body sites, and provides for the first time the ability to directly compare the case-control effect sizes of a wide range of pain sensitivity measures. PMID:22074753

Economics of infection control surveillance technology: cost-effective or just cost?

PubMed

Furuno, Jon P; Schweizer, Marin L; McGregor, Jessina C; Perencevich, Eli N

2008-04-01

Previous studies have suggested that informatics tools, such as automated alert and decision support systems, may increase the efficiency and quality of infection control surveillance. However, little is known about the cost-effectiveness of these tools. We focus on 2 types of economic analyses that have utility in assessing infection control interventions (cost-effectiveness analysis and business-case analysis) and review the available literature on the economics of computerized infection control surveillance systems. Previous studies on the effectiveness of computerized infection control surveillance have been limited to assessments of whether these tools increase the sensitivity and specificity of surveillance over traditional methods. Furthermore, we identified only 2 studies that assessed the costs associated with computerized infection control surveillance. Thus, it remains unknown whether computerized infection control surveillance systems are cost-effective and whether use of these systems improves patient outcomes. The existing data are insufficient to allow for a summary conclusion on the cost-effectiveness of infection control surveillance technology. All future studies of computerized infection control surveillance systems should aim to collect outcomes and economic data to inform decision making and assist hospitals with completing business-cases analyses.

Identification of a genetic variant associated with abdominal aortic aneurysms on chromosome 3p12.3 by genome wide association.

PubMed

Elmore, James R; Obmann, Melissa A; Kuivaniemi, Helena; Tromp, Gerard; Gerhard, Glenn S; Franklin, David P; Boddy, Amy M; Carey, David J

2009-06-01

The goal of this project was to identify genetic variants associated with abdominal aortic aneurysms (AAAs). A genome wide association study was carried out using pooled DNA samples from 123 AAA cases and 112 controls matched for age, gender, and smoking history using Affymetrix 500K single nucleotide polymorphism (SNP) arrays (Affymetrix, Inc, Santa Clara, Calif). The difference in mean allele frequency between cases and controls was calculated for each SNP and used to identify candidate genomic regions. Association of candidate SNPs with AAA was confirmed by individual TaqMan genotype assays in a total of 2096 cases and controls that included an independent replication sample set. A genome wide association study of AAA cases and controls identified a candidate AAA-associated haplotype on chromosome 3p12.3. By individual genotype analysis, four SNPs in this region were significantly associated with AAA in cases and controls from the original study population. One SNP in this region (rs7635818) was genotyped in a total of 502 cases and 736 controls from the original study population (P = .017) and 448 cases and 410 controls from an independent replication sample (P = .013; combined P value = .0028; combined odds ratio [OR] = 1.33). An even stronger association with AAA was observed in a subset of smokers (391 cases, 241 controls, P = .00041, OR = 1.80), which represent the highest risk group for AAA. The AAA-associated haplotype is located approximately 200 kbp upstream of the CNTN3 gene transcription start site. This study identifies a region on chromosome 3 that is significantly associated with AAA in 2 distinct study populations.

Analgesics use and ESRD in younger age: a case-control study

PubMed Central

van der Woude, Fokke J; Heinemann, Lothar AJ; Graf, Helmut; Lewis, Michael; Moehner, Sabine; Assmann, Anita; Kühl-Habich, Doerthe

2007-01-01

Background An ad hoc peer-review committee was jointly appointed by Drug Authorities and Industry in Germany, Austria and Switzerland in 1999/2000 to review the evidence for a causal relation between phenacetin-free analgesics and nephropathy. The committee found the evidence as inconclusive and requested a new case-control study of adequate design. Methods We performed a population-based case-control study with incident cases of end-stage renal disease (ESRD) under the age of 50 years and four age and sex-matched neighborhood controls in 170 dialysis centers (153 in Germany, and 17 in Austria) from January 1, 2001 to December 31, 2004. Data on lifetime medical history, risk factors, treatment, job exposure and intake of analgesics were obtained in a standardized face-to-face interview using memory aids to enhance accuracy. Study design, study performance, analysis plan, and study report were approved by an independent international advisory committee and by the Drug Authorities involved. Unconditional logistic regression analyses were performed. Results The analysis included 907 cases and 3,622 controls who had never used phenacetin-containing analgesics in their lifetime. The use of high cumulative lifetime dose (3rd tertile) of analgesics in the period up to five years before dialysis was not associated with later ESRD. Adjusted odds ratios with 95% confidence intervals were 0.8 (0.7 – 1.0) and 1.0 (0.8 – 1.3) for ever- compared with no or low use and high use compared with low use, respectively. The same results were found for all analgesics and for mono-, and combination preparations with and without caffeine. No increased risk was shown in analyses stratifying for dose and duration. Dose-response analyses showed that analgesic use was not associated with an increased risk for ESRD up to 3.5 kg cumulative lifetime dose (98 % of the cases with ESRD). While the large subgroup of users with a lifetime dose up to 0.5 kg (278 cases and 1365 controls) showed a significantly decreased risk, a tiny subgroup of extreme users with over 3.5 kg lifetime use (19 cases and 11 controls) showed a significant risk increase. The detailed evaluation of 22 cases and 19 controls with over 2.5 kg lifetime use recommended by the regulatory advisors showed an impressive excess of other conditions than analgesics triggering the evolution of ESRD in cases compared with controls. Conclusion We found no clinically meaningful evidence for an increased risk of ESRD associated with use of phenacetin-free analgesics in single or combined formulation. The apparent risk increase shown in a small subgroup with extreme lifetime dose of analgesics is most likely an indirect, non-causal association. This hypothesis, however, cannot be confirmed or refuted within our case-control study. Overall, our results lend support to the mounting evidence that phenacetin-free analgesics do not induce ESRD and that the notion of "analgesic nephropathy" needs to be re-evaluated. PMID:18053232

Use of methimazole and risk of acute pancreatitis: A case-control study in Taiwan.

PubMed

Lai, Shih-Wei; Lin, Cheng-Li; Liao, Kuan-Fu

2016-01-01

Some cases of acute pancreatitis have been reported to be associated with use of methimazole. The aim of this study was to investigate the relationship between use of methimazole and risk of acute pancreatitis on the basis of a systematic analysis. This was a population-based case-control study analyzing the database of the Taiwan National Health Insurance Program. There were 5764 individuals aged 20-84 years with a first attack of acute pancreatitis from 1998 to 2011 as the cases and 23,056 randomly selected sex- and age-matched individuals without acute pancreatitis as the controls. Use of methimazole was categorized as "never use" and "ever use." We estimated the relative risk of acute pancreatitis associated with the use of methimazole by calculating the odds ratio (OR) with 95% confidence interval (CI) using a multivariable logistic regression model. After adjustment for confounding factors, the OR of acute pancreatitis was 0.91 in individuals with ever use of methimazole, when compared with individuals with never use of methimazole (95% CI, 0.60-1.38). Unlike methimazole use, alcohol-related disease, biliary stone, cardiovascular disease, chronic obstructive pulmonary disease, diabetes mellitus, hepatitis B, hepatitis C, and hypertriglyceridemia were factors significantly associated with acute pancreatitis. Our study does not detect a substantial association between the use of methimazole and risk of acute pancreatitis on the basis of systematic analysis. There appears to be a discrepancy between case reports and our systematic analysis about the association between the use of methimazole and risk of acute pancreatitis.

Therapeutic value of selective salpingography for infertile women with patent fallopian tubes: the impact on pregnancy rate.

PubMed

Kamiyama, S; Miyagi, H; Kanazawa, K

2000-01-01

To determine the therapeutic value of selective salpingography (SSG) for infertile women with patent fallopian tubes. Retrospective, case-control analysis. University Hospital, infertility clinic. Infertile cases with patent tubes documented by hysterosalpingography (HSG) or by HSG followed by laparoscopic examination (n = 80). Hysteroscopic SSG. Patency rate of tubes by SSG. Pregnancy rate following SSG. Eighty cases were divided into the study group (SSG performed, 37 cases) and the case-control group (SSG not performed, 43 cases). Successful SSG of at least one tube was obtained in all of 37 cases (100%) in whom SSG was attempted. A patency rate of 95.9% was documented in the 73 cannulated tubes of these cases. The total subsequent pregnancy rate (48.6%) within 12 months of follow-up after SSG was significantly higher than that (11.6%) obtained in the control group (p < 0.001). The cumulative pregnancy rate in the study group was also significantly higher than that in the control group (p < 0.001). The findings of the present study encourage the application of SSG to infertile women, either as a sole therapeutic approach or in association with other methods of assisted reproductive technology, even if their fallopian tubes are shown to be patent by HSG. Copyright 2000 S. Karger AG, Basel

A Case-control Study of Diphtheria in the High Incidence City of Hyderabad, India.

PubMed

Allam, Ramesh Reddy; Uthappa, Chengappa Kechamada; Duerst, Rebecca; Sorley, Evan; Udaragudi, Prasada Rao; Kampa, Shankar; Dworkin, Mark S

2016-03-01

India accounts for approximately 72% of reported diphtheria cases globally, the majority of which occur in the state of Andhra Pradesh. The aim of this study is to better understand lack of knowledge on diphtheria vaccination and to determine factors associated with diphtheria and low knowledge and negative attitudes. We performed a 1:1 case-control study of hospitalized diphtheria cases in Hyderabad. Eligible case patients were 10 years of age or older, resided within the city of Hyderabad and were diagnosed with diphtheria per the case definition. Patients admitted to the hospital for nonrespiratory communicable diseases and residing in the same geographic region as that of cases were eligible for enrolment as controls : There were no statistical differences in disease outcome by gender, education, economic status and mean room per person sleeping in the house in case and control subjects. Not having heard of diphtheria (adjusted odds ratio: 3.56; 95% confidence intervals: 1.58-8.04] and not believing that vaccines can prevent people from getting diseases (adjusted odds ratio: 3.99; 95% confidence intervals: 1.18-13.45) remained significantly associated with diphtheria on multivariate analysis. To reduce the burden of diphtheria in India, further efforts to educate the public about diphtheria should be considered.

Effects of a blended learning module on self-reported learning performances in baccalaureate nursing students.

PubMed

Hsu, Li-Ling; Hsieh, Suh-Ing

2011-11-01

This article is a report of a quasi-experimental study of the effects of blended modules on nursing students' learning of ethics course content. There is yet to be an empirically supported mix of strategies on which a working blended learning model can be built for nursing education. This was a two-group pretest and post-test quasi-experimental study in 2008 involving a total of 233 students. Two of the five clusters were designated the experimental group to experience a blended learning model, and the rest were designated the control group to be given classroom lectures only. The Case Analysis Attitude Scale, Case Analysis Self-Evaluation Scale, Blended Learning Satisfaction Scale, and Metacognition Scale were used in pretests and post-tests for the students to rate their own performance. In this study, the experimental group did not register significantly higher mean scores on the Case Analysis Attitude Scale at post-test and higher mean ranks on the Case Analysis Self-Evaluation Scale, the Blended Learning Satisfaction Scale, and the Metacognition Scale at post-test than the control group. Moreover, the experimental group registered significant progress in the mean ranks on the Case Analysis Self-Evaluation Scale and the Metacognition Scale from pretest to post-test. No between-subjects effects of four scales at post-test were found. Newly developed course modules, be it blended learning or a combination of traditional and innovative components, should be tested repeatedly for effectiveness and popularity for the purpose of facilitating the ultimate creation of a most effective course module for nursing education. © 2011 Blackwell Publishing Ltd.

Meta- and Pooled Analysis of GSTP1 Polymorphism and Lung Cancer: A HuGE-GSEC Review

PubMed Central

Chen, Wei; Smith, Daryn W.; Benhamou, Simone; Bouchardy, Christine; Butkiewicz, Dorota; Fong, Kwun M.; Gené, Manuel; Hirvonen, Ari; Kiyohara, Chikako; Larsen, Jill E.; Lin, Pinpin; Raaschou-Nielsen, Ole; Povey, Andrew C.; Reszka, Edyta; Risch, Angela; Schneider, Joachim; Schwartz, Ann G.; Sorensen, Mette; To-Figueras, Jordi; Tokudome, Shinkan; Pu, Yuepu; Yang, Ping; Wenzlaff, Angela S.; Wikman, Harriet; Taioli, Emanuela

2009-01-01

Lung cancer is the most common cancer worldwide. Polymorphisms in genes associated with carcinogen metabolism may modulate risk of disease. Glutathione S-transferase pi (GSTP1) detoxifies polycyclic aromatic hydrocarbons found in cigarette smoke and is the most highly expressed glutathione S-transferase in lung tissue. A polymorphism in the GSTP1 gene, an A-to-G transition in exon 5 (Ile105Val, 313A → 313G), results in lower activity among individuals who carry the valine allele. The authors present a meta- and a pooled analysis of case-control studies that examined the association between this polymorphism in GSTP1 and lung cancer risk (27 studies, 8,322 cases and 8,844 controls and 15 studies, 4,282 cases and 5,032 controls, respectively). Overall, the meta-analysis found no significant association between lung cancer risk and the GSTP1 exon 5 polymorphism. In the pooled analysis, there was an overall association (odds ratio = 1.11, 95% confidence interval: 1.03, 1.21) between lung cancer and carriage of the GSTP1 Val/Val or Ile/Val genotype compared with those carrying the Ile/Ile genotype. Increased risk varied by histologic type in Asians. There appears to be evidence for interaction between amount of smoking, the GSTP1 exon 5 polymorphism, and risk of lung cancer in whites. PMID:19240225

Polymorphisms of three genes (ACE, AGT and CYP11B2) in the renin-angiotensin-aldosterone system are not associated with blood pressure salt sensitivity: A systematic meta-analysis.

PubMed

Sun, Jiahong; Zhao, Min; Miao, Song; Xi, Bo

2016-01-01

Many studies have suggested that polymorphisms of three key genes (ACE, AGT and CYP11B2) in the renin-angiotensin-aldosterone system (RAAS) play important roles in the development of blood pressure (BP) salt sensitivity, but they have revealed inconsistent results. Thus, we performed a meta-analysis to clarify the association. PubMed and Embase databases were searched for eligible published articles. Fixed- or random-effect models were used to pool odds ratios and 95% confidence intervals based on whether there was significant heterogeneity between studies. In total, seven studies [237 salt-sensitive (SS) cases and 251 salt-resistant (SR) controls] for ACE gene I/D polymorphism, three studies (130 SS cases and 221 SR controls) for AGT gene M235T polymorphism and three studies (113 SS cases and 218 SR controls) for CYP11B2 gene C344T polymorphism were included in this meta-analysis. The results showed that there was no significant association between polymorphisms of these three polymorphisms in the RAAS and BP salt sensitivity under three genetic models (all p > 0.05). The meta-analysis suggested that three polymorphisms (ACE gene I/D, AGT gene M235T, CYP11B2 gene C344T) in the RAAS have no significant effect on BP salt sensitivity.

Occupational exposure to respirable crystalline silica and chronic non-malignant renal disease: systematic review and meta-analysis.

PubMed

Möhner, Matthias; Pohrt, Anne; Gellissen, Johannes

2017-10-01

While occupational exposure to respirable silica is known to lead to lung disease, most notably silicosis, its association with chronic kidney disease is unclear. This review explores the association between occupational exposure to respirable silica and chronic non-malignant renal disease such as glomerulonephritis. The evidence has been collected and compiled. Possible sources of bias are thoroughly discussed. Cohort studies with silica exposure and case-control studies of renal disease were searched in PubMed until January 2015. Two authors independently abstracted data; any disagreement was resolved by consulting a third reviewer. A meta-analysis was performed to evaluate the association to silica exposure. A total of 23 cohort and four case-control studies were included in the analysis. The meta-analysis of cohort studies yielded elevated overall SMRs for renal disease. Some studies, however, included dose-response analyses, most of which did not show a positive trend. The approaches and results of the case-control studies were very heterogeneous. While the studies of cohorts exposed to silica found elevated SMRs for renal disease, no clear evidence of a dose-response relationship emerged. The elevated risk may be attributed to diagnostic and methodological issues. In order to permit a reliable estimation of a possible causal link, exposed cohorts should be monitored for renal disease, as the information from mortality studies is hardly reliable in this field.

Genetic analysis of hyperemesis gravidarum reveals association with intracellular calcium release channel (RYR2).

PubMed

Fejzo, Marlena Schoenberg; Myhre, Ronny; Colodro-Conde, Lucía; MacGibbon, Kimber W; Sinsheimer, Janet S; Reddy, M V Prasad Linga; Pajukanta, Päivi; Nyholt, Dale R; Wright, Margaret J; Martin, Nicholas G; Engel, Stephanie M; Medland, Sarah E; Magnus, Per; Mullin, Patrick M

2017-01-05

Hyperemesis Gravidarum (HG), severe nausea/vomiting in pregnancy (NVP), can cause poor maternal/fetal outcomes. Genetic predisposition suggests the genetic component is essential in discovering an etiology. We performed whole-exome sequencing of 5 families followed by analysis of variants in 584 cases/431 controls. Variants in RYR2 segregated with disease in 2 families. The novel variant L3277R was not found in any case/control. The rare variant, G1886S was more common in cases (p = 0.046) and extreme cases (p = 0.023). Replication of G1886S using Norwegian/Australian data was supportive. Common variants rs790899 and rs1891246 were significantly associated with HG and weight loss. Copy-number analysis revealed a deletion in a patient. RYR2 encodes an intracellular calcium release channel involved in vomiting, cyclic-vomiting syndrome, and is a thyroid hormone target gene. Additionally, RYR2 is a downstream drug target of Inderal, used to treat HG and CVS. Thus, herein we provide genetic evidence for a pathway and therapy for HG. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Risk factors for hepatitis B in an outbreak of hepatitis B and D among injection drug users.

PubMed

Bialek, Stephanie R; Bower, William A; Mottram, Karen; Purchase, Dave; Nakano, T; Nainan, Omana; Williams, Ian T; Bell, Beth P

2005-09-01

During January-April, 2000, 12 cases of acute hepatitis B were reported in Pierce County, Washington, compared with seven in all of 1999. Seven (58.3%) case patients were injection drug users (IDUs), three of whom were coinfected with hepatitis D virus (HDV) and died of fulminant hepatitis. Vaccination clinics were implemented at the local health department and needle exchange program to control the outbreak. We investigated this outbreak to determine risk factors for hepatitis B virus (HBV) transmission among IDUs. Hepatitis B cases were ascertained through routine surveillance and prevaccination testing at vaccination clinics. We conducted a case-control study comparing IDU case patients with HBV-susceptible IDUs identified at the vaccination clinics. Fifty-eight case patients were identified during January-December, 2000, 20 (34.5%) of whom were coinfected with HDV. Thirty-eight case patients (65.5%) reported current IDU. In the case-control study, the 17 case patients were more likely than the 141 controls to report having more than one sex partner [odds ratio (OR) =4.8, 95% confidence interval (CI) =1.5-15.0], injecting more than four times a day (OR = 4.5, 95% CI =1.2-15.6) and sharing drug cookers with more than two people (58.8% vs. 14.0%, OR =14.0, 95% CI =2.4-81.5). Results were similar after controlling for syringe sharing in multivariable analysis. IDUs should be vaccinated against hepatitis B and should be advised against sharing drug injection equipment.

Predicting Local Dengue Transmission in Guangzhou, China, through the Influence of Imported Cases, Mosquito Density and Climate Variability

PubMed Central

Sang, Shaowei; Yin, Wenwu; Bi, Peng; Zhang, Honglong; Wang, Chenggang; Liu, Xiaobo; Chen, Bin; Yang, Weizhong; Liu, Qiyong

2014-01-01

Introduction Each year there are approximately 390 million dengue infections worldwide. Weather variables have a significant impact on the transmission of Dengue Fever (DF), a mosquito borne viral disease. DF in mainland China is characterized as an imported disease. Hence it is necessary to explore the roles of imported cases, mosquito density and climate variability in dengue transmission in China. The study was to identify the relationship between dengue occurrence and possible risk factors and to develop a predicting model for dengue’s control and prevention purpose. Methodology and Principal Findings Three traditional suburbs and one district with an international airport in Guangzhou city were selected as the study areas. Autocorrelation and cross-correlation analysis were used to perform univariate analysis to identify possible risk factors, with relevant lagged effects, associated with local dengue cases. Principal component analysis (PCA) was applied to extract principal components and PCA score was used to represent the original variables to reduce multi-collinearity. Combining the univariate analysis and prior knowledge, time-series Poisson regression analysis was conducted to quantify the relationship between weather variables, Breteau Index, imported DF cases and the local dengue transmission in Guangzhou, China. The goodness-of-fit of the constructed model was determined by pseudo-R2, Akaike information criterion (AIC) and residual test. There were a total of 707 notified local DF cases from March 2006 to December 2012, with a seasonal distribution from August to November. There were a total of 65 notified imported DF cases from 20 countries, with forty-six cases (70.8%) imported from Southeast Asia. The model showed that local DF cases were positively associated with mosquito density, imported cases, temperature, precipitation, vapour pressure and minimum relative humidity, whilst being negatively associated with air pressure, with different time lags. Conclusions Imported DF cases and mosquito density play a critical role in local DF transmission, together with weather variables. The establishment of an early warning system, using existing surveillance datasets will help to control and prevent dengue in Guangzhou, China. PMID:25019967

Predicting local dengue transmission in Guangzhou, China, through the influence of imported cases, mosquito density and climate variability.

PubMed

Sang, Shaowei; Yin, Wenwu; Bi, Peng; Zhang, Honglong; Wang, Chenggang; Liu, Xiaobo; Chen, Bin; Yang, Weizhong; Liu, Qiyong

2014-01-01

Each year there are approximately 390 million dengue infections worldwide. Weather variables have a significant impact on the transmission of Dengue Fever (DF), a mosquito borne viral disease. DF in mainland China is characterized as an imported disease. Hence it is necessary to explore the roles of imported cases, mosquito density and climate variability in dengue transmission in China. The study was to identify the relationship between dengue occurrence and possible risk factors and to develop a predicting model for dengue's control and prevention purpose. Three traditional suburbs and one district with an international airport in Guangzhou city were selected as the study areas. Autocorrelation and cross-correlation analysis were used to perform univariate analysis to identify possible risk factors, with relevant lagged effects, associated with local dengue cases. Principal component analysis (PCA) was applied to extract principal components and PCA score was used to represent the original variables to reduce multi-collinearity. Combining the univariate analysis and prior knowledge, time-series Poisson regression analysis was conducted to quantify the relationship between weather variables, Breteau Index, imported DF cases and the local dengue transmission in Guangzhou, China. The goodness-of-fit of the constructed model was determined by pseudo-R2, Akaike information criterion (AIC) and residual test. There were a total of 707 notified local DF cases from March 2006 to December 2012, with a seasonal distribution from August to November. There were a total of 65 notified imported DF cases from 20 countries, with forty-six cases (70.8%) imported from Southeast Asia. The model showed that local DF cases were positively associated with mosquito density, imported cases, temperature, precipitation, vapour pressure and minimum relative humidity, whilst being negatively associated with air pressure, with different time lags. Imported DF cases and mosquito density play a critical role in local DF transmission, together with weather variables. The establishment of an early warning system, using existing surveillance datasets will help to control and prevent dengue in Guangzhou, China.

The significance of OLGA and OLGIM staging systems in the risk assessment of gastric cancer: a systematic review and meta-analysis.

PubMed

Yue, Hu; Shan, Liu; Bin, Lv

2018-02-19

Despite extensive research on the criteria for the assessment of gastric cancer risk using the Operative Link on Gastritis Assessment (OLGA) and Operative Link on Gastritis/Intestinal-Metaplasia Assessment (OLGIM) systems, no comprehensive overview or systematic summary on their use is currently available. To perform a systematic review and meta-analysis to assess the efficacy of the OLGA and OLGIM staging systems in evaluating gastric cancer risk. We searched various databases, including PubMed, EMBASE, Medline, and Cochrane's library, for articles published before March 2017 on the association between OLGA/OLGIM stages and risk of gastric cancer. Statistical analysis was performed using RevMan 5.30 and Stata 14.0, with the odds ratio, risk ratio, and 95% confidence interval as the effect measures. A meta-analysis of six case-control studies and two cohort studies, comprising 2700 subjects, was performed. The meta-analysis of prospective case-control studies demonstrated a significant association between the OLGA/OLGIM stages III/IV and gastric cancer. The Newcastle-Ottawa Scale (NOS) score reflected heterogeneity in the case-control studies on OLGA. Subgroup analysis of high-quality (NOS score ≥ 5) studies showed an association between OLGA stage III/IV and increased risk of gastric cancer; the association was also high in the remaining study with low NOS score. The association between higher stages of gastritis defined by OLGA and risk of gastric cancer was significant. This correlation implies that close and frequent monitoring of such high-risk patients is necessary to facilitate timely diagnosis of gastric cancer.

Alcohol Intake and Risk of Thyroid Cancer: A Meta-Analysis of Observational Studies.

PubMed

Hong, Seung-Hee; Myung, Seung-Kwon; Kim, Hyeon Suk

2017-04-01

The purpose of this study was to assess whether alcohol intake is associated with the risk of thyroid cancer by a meta-analysis of observational studies. We searched PubMed and EMBASE in June of 2015 to locate eligible studies. We included observational studies such as cross-sectional studies, case-control studies, and cohort studies reporting odd ratios (ORs) or relative risk (RRs) with 95% confidence intervals (CIs). We included 33 observational studies with two cross-sectional studies, 20 case-controls studies, and 11 cohort studies, which involved a total of 7,725 thyroid cancer patients and 3,113,679 participants without thyroid cancer in the final analysis. In the fixed-effect model meta-analysis of all 33 studies, we found that alcohol intake was consistently associated with a decreased risk of thyroid cancer (OR or RR, 0.74; 95% CI, 0.67 to 0.83; I 2 =38.6%). In the subgroup meta-analysis by type of study, alcohol intake also decreased the risk of thyroid cancer in both case-control studies (OR, 0.77; 95% CI, 0.65 to 0.92; I 2 =29.5%; n=20) and cohort studies (RR, 0.70; 95% CI, 0.60 to 0.82; I 2 =0%; n=11). Moreover, subgroup meta-analyses by type of thyroid cancer, gender, amount of alcohol consumed, and methodological quality of study showed that alcohol intake was significantly associated with a decreased risk of thyroid cancer. The current meta-analysis of observational studies found that, unlike most of other types of cancer, alcohol intake decreased the risk of thyroid cancer.

Gut microbiota in early pediatric multiple sclerosis: a case-control study.

PubMed

Tremlett, Helen; Fadrosh, Douglas W; Faruqi, Ali A; Zhu, Feng; Hart, Janace; Roalstad, Shelly; Graves, Jennifer; Lynch, Susan; Waubant, Emmanuelle

2016-08-01

Alterations in the gut microbial community composition may be influential in neurological disease. Microbial community profiles were compared between early onset pediatric multiple sclerosis (MS) and control children similar for age and sex. Children ≤18 years old within 2 years of MS onset or controls without autoimmune disorders attending a University of California, San Francisco, USA, pediatric clinic were examined for fecal bacterial community composition and predicted function by 16S ribosomal RNA sequencing and phylogenetic reconstruction of unobserved states (PICRUSt) analysis. Associations between subject characteristics and the microbiota, including beta diversity and taxa abundance, were identified using non-parametric tests, permutational multivariate analysis of variance and negative binomial regression. Eighteen relapsing-remitting MS cases and 17 controls (mean age 13 years; range 4-18) were studied. Cases had a short disease duration (mean 11 months; range 2-24) and half were immunomodulatory drug (IMD) naïve. Whilst overall gut bacterial beta diversity was not significantly related to MS status, IMD exposure was (Canberra, P < 0.02). However, relative to controls, MS cases had a significant enrichment in relative abundance for members of the Desulfovibrionaceae (Bilophila, Desulfovibrio and Christensenellaceae) and depletion in Lachnospiraceae and Ruminococcaceae (all P and q < 0.000005). Microbial genes predicted as enriched in MS versus controls included those involved in glutathione metabolism (Mann-Whitney, P = 0.017), findings that were consistent regardless of IMD exposure. In recent onset pediatric MS, perturbations in the gut microbiome composition were observed, in parallel with predicted enrichment of metabolic pathways associated with neurodegeneration. Findings were suggestive of a pro-inflammatory milieu. © 2016 EAN.

An Analysis of 19 International Case Studies of Stress Prevention Through Work Reorganization Using the Demand/Control Model

ERIC Educational Resources Information Center

Karasek, Robert A.

2004-01-01

Nineteen international case studies of workplace stress prevention initiatives are analyzed. The focus of these cases, which span a variety of workplaces and locations, is on preventing stress through work reorganization rather than remedial approaches for stress relief. It is found that the majority of the occupations represented in the case…

Association between glutathione S-transferase P1 Ile (105) Val gene polymorphism and chronic obstructive pulmonary disease: A meta-analysis based on seventeen case-control studies.

PubMed

Yang, Lingjing; Li, Xixia; Tong, Xiang; Fan, Hong

2015-12-01

Previous studies have shown that glutathione S-transferase P1 (GSTP1) was associated with chronic obstructive pulmonary disease (COPD). However, the association between GSTP1 Ile (105) Val gene polymorphism and COPD remains controversial. To drive a more precise estimation, we performed a meta-analysis based on published case-control studies. An electronic search of PubMed, EMBASE, Cochrane library, Web of Science and China Knowledge Resource Integrated (CNKI) Database for papers on GSTP1 Ile (105) Val gene polymorphism and COPD risk was performed. The pooled odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of association in the homozygote model, heterozygote model, dominant model, recessive model and an additive mode. Statistical heterogeneity, test of publication bias and sensitivity analysis was performed. The software STATA (Version 13.0) was used data analysis. Overall, seventeen studies with 1892 cases and 2012 controls were included in this meta-analysis. The GSTP1 Ile (105) Val polymorphism showed pooled odds ratios for the homozygote comparison (OR = 1.501, 95%CI [0.862, 2.614]), heterozygote comparison (OR = 0.924, 95%CI [0.733, 1.165]), dominant model (OR = 1.003, 95%CI [0.756, 1.331]), recessive model (OR = 1.510, 95%CI [0.934, 2.439]), and an additive model (OR = 1.072, 95%CI [0.822, 1.398]). In conclusion, the current meta-analysis, based on the most updated information, showed no significant association between GSTP1 Ile (105) Val gene polymorphism and COPD risk in any genetic models. The results of subgroup analysis also showed no significant association between GSTP1 Ile (105) Val gene polymorphism and COPD risk in Asian population and Caucasian population. Further studies involving large populations and careful control with age, sex, ethnicity, and cigarette smoking are greatly needed.

Is gamma-glutamyl transpeptidase a biomarker for oxidative stress in periodontitis?

PubMed Central

Sreeram, Meenakshi; Suryakar, Adinath Narayan; Dani, Nitin Hemchandra

2015-01-01

Context: Periodontal disease and oxidative stress (OS) are part of a vicious cycle with each causing a deleterious effect on the other causing changes in the levels of antioxidants, and enzymes of antioxidant defense. Biomarkers and methods used for measuring OS are very expensive. Aims: To see how gamma-glutamyltransferase (GGT) fares, as a biomarker for OS in periodontits along with other routinely used biomarkers. Design: A cross-sectional study involving 300 people of which 150 were cases and 150 were controls. Setting: Candidates enrolled were patients visiting the OPD of MGV's Dental College and Hospital, Nasik, India between January 2011 and December 2012. Materials and Methods: Serum samples of patients with periodontitis, and controls were analyzed for malondialdehyde, superoxide dismutase (SOD), glutathione peroxidase (GPx), uric acid, and GGT. Statistical Analysis Used: Analysis was performed using Student's t test. P <0.05 were considered to be significant. Results: Malondialdehyde values were found to be significantly higher cases, while SOD, GPx and uric acid levels were found to be lower than controls. GGT levels were significantly higher in cases as compared to controls. Conclusions: GGT may be used as a cheap, quick, easy and precise marker for measuring OS. PMID:26015663

Potential for Controlling Cholera Using a Ring Vaccination Strategy: Re-analysis of Data from a Cluster-Randomized Clinical Trial.

PubMed

Ali, Mohammad; Debes, Amanda K; Luquero, Francisco J; Kim, Deok Ryun; Park, Je Yeon; Digilio, Laura; Manna, Byomkesh; Kanungo, Suman; Dutta, Shanta; Sur, Dipika; Bhattacharya, Sujit K; Sack, David A

2016-09-01

Vaccinating a buffer of individuals around a case (ring vaccination) has the potential to target those who are at highest risk of infection, reducing the number of doses needed to control a disease. We explored the potential vaccine effectiveness (VE) of oral cholera vaccines (OCVs) for such a strategy. This analysis uses existing data from a cluster-randomized clinical trial in which OCV or placebo was given to 71,900 participants in Kolkata, India, from 27 July to 10 September 2006. Cholera surveillance was then conducted on 144,106 individuals living in the study area, including trial participants, for 5 y following vaccination. First, we explored the risk of cholera among contacts of cholera patients, and, second, we measured VE among individuals living within 25 m of cholera cases between 8 and 28 d after onset of the index case. For the first analysis, individuals living around each index case identified during the 5-y period were assembled using a ring to define cohorts of individuals exposed to cholera index cases. An index control without cholera was randomly selected for each index case from the same population, matched by age group, and individuals living around each index control were assembled using a ring to define cohorts not exposed to cholera cases. Cholera attack rates among the exposed and non-exposed cohorts were compared using different distances from the index case/control to define the rings and different time frames to define the period at risk. For the VE analysis, the exposed cohorts were further stratified according to the level of vaccine coverage into high and low coverage strata. Overall VE was assessed by comparing the attack rates between high and low vaccine coverage strata irrespective of individuals' vaccination status, and indirect VE was assessed by comparing the attack rates among unvaccinated members between high and low vaccine coverage strata. Cholera risk among the cohort exposed to cholera cases was 5-11 times higher than that among the cohort not exposed to cholera cases. The risk gradually diminished with an increase in distance and time. The overall and indirect VE measured between 8 and 28 d after exposure to a cholera index case during the first 2 y was 91% (95% CI 62%-98%) and 93% (95% CI 44%-99%), respectively. VE persisted for 5 y after vaccination and was similar whether the index case was a young child (<5 y) or was older. Of note, this study was a reanalysis of a cholera vaccine trial that used two doses; thus, a limitation of the study relates to the assumption that a single dose, if administered quickly, will induce a similar level of total and indirect protection over the short term as did two doses. These findings suggest that high-level protection can be achieved if individuals living close to cholera cases are living in a high coverage ring. Since this was an observational study including participants who had received two doses of vaccine (or placebo) in the clinical trial, further studies are needed to determine whether a ring vaccination strategy, in which vaccine is given quickly to those living close to a case, is feasible and effective. ClinicalTrials.gov NCT00289224.

Potential for Controlling Cholera Using a Ring Vaccination Strategy: Re-analysis of Data from a Cluster-Randomized Clinical Trial

PubMed Central

Ali, Mohammad; Luquero, Francisco J.; Kim, Deok Ryun; Park, Je Yeon; Digilio, Laura; Manna, Byomkesh; Kanungo, Suman; Dutta, Shanta; Sur, Dipika; Bhattacharya, Sujit K.

2016-01-01

Introduction Vaccinating a buffer of individuals around a case (ring vaccination) has the potential to target those who are at highest risk of infection, reducing the number of doses needed to control a disease. We explored the potential vaccine effectiveness (VE) of oral cholera vaccines (OCVs) for such a strategy. Methods and Findings This analysis uses existing data from a cluster-randomized clinical trial in which OCV or placebo was given to 71,900 participants in Kolkata, India, from 27 July to 10 September 2006. Cholera surveillance was then conducted on 144,106 individuals living in the study area, including trial participants, for 5 y following vaccination. First, we explored the risk of cholera among contacts of cholera patients, and, second, we measured VE among individuals living within 25 m of cholera cases between 8 and 28 d after onset of the index case. For the first analysis, individuals living around each index case identified during the 5-y period were assembled using a ring to define cohorts of individuals exposed to cholera index cases. An index control without cholera was randomly selected for each index case from the same population, matched by age group, and individuals living around each index control were assembled using a ring to define cohorts not exposed to cholera cases. Cholera attack rates among the exposed and non-exposed cohorts were compared using different distances from the index case/control to define the rings and different time frames to define the period at risk. For the VE analysis, the exposed cohorts were further stratified according to the level of vaccine coverage into high and low coverage strata. Overall VE was assessed by comparing the attack rates between high and low vaccine coverage strata irrespective of individuals’ vaccination status, and indirect VE was assessed by comparing the attack rates among unvaccinated members between high and low vaccine coverage strata. Cholera risk among the cohort exposed to cholera cases was 5–11 times higher than that among the cohort not exposed to cholera cases. The risk gradually diminished with an increase in distance and time. The overall and indirect VE measured between 8 and 28 d after exposure to a cholera index case during the first 2 y was 91% (95% CI 62%–98%) and 93% (95% CI 44%–99%), respectively. VE persisted for 5 y after vaccination and was similar whether the index case was a young child (<5 y) or was older. Of note, this study was a reanalysis of a cholera vaccine trial that used two doses; thus, a limitation of the study relates to the assumption that a single dose, if administered quickly, will induce a similar level of total and indirect protection over the short term as did two doses. Conclusions These findings suggest that high-level protection can be achieved if individuals living close to cholera cases are living in a high coverage ring. Since this was an observational study including participants who had received two doses of vaccine (or placebo) in the clinical trial, further studies are needed to determine whether a ring vaccination strategy, in which vaccine is given quickly to those living close to a case, is feasible and effective. Trial registration ClinicalTrials.gov NCT00289224 PMID:27622507

Modeling the outcomes of nursing home care.

PubMed

Rohrer, J E; Hogan, A J

1987-01-01

In this exploratory analysis using data on 290 patients, we use regression analysis to model patient outcomes in two Veterans Administration nursing homes. We find resource use, as measured with minutes of nursing time, to be associated with outcomes when case mix is controlled. Our results suggest that, under case-based reimbursement systems, nursing homes could increase their revenues by withholding unskilled and psychosocial care and discouraging physicians' visits. Implications for nursing home policy are discussed.

A Performance Management Framework for Civil Engineering

DTIC Science & Technology

1990-09-01

cultural change. A non - equivalent control group design was chosen to augment the case analysis. Figure 3.18 shows the form of the quasi-experiment. The...The non - equivalent control group design controls the following obstacles to internal validity: history, maturation, testing, and instrumentation. The...and Stanley, 1963:48,50) Table 7. Validity of Quasi-Experiment The non - equivalent control group experimental design controls the following obstacles to

Assimilation of Quality Controlled AIRS Temperature Profiles using the NCEP GFS

NASA Technical Reports Server (NTRS)

Susskind, Joel; Reale, Oreste; Iredell, Lena; Rosenberg, Robert

2013-01-01

We have previously conducted a number of data assimilation experiments using AIRS Version-5 quality controlled temperature profiles as a step toward finding an optimum balance of spatial coverage and sounding accuracy with regard to improving forecast skill. The data assimilation and forecast system we used was the Goddard Earth Observing System Model , Version-5 (GEOS-5) Data Assimilation System (DAS), which represents a combination of the NASA GEOS-5 forecast model with the National Centers for Environmental Prediction (NCEP) operational Grid Point Statistical Interpolation (GSI) global analysis scheme. All analyses and forecasts were run at a 0.5deg x 0.625deg spatial resolution. Data assimilation experiments were conducted in four different seasons, each in a different year. Three different sets of data assimilation experiments were run during each time period: Control; AIRS T(p); and AIRS Radiance. In the "Control" analysis, all the data used operationally by NCEP was assimilated, but no AIRS data was assimilated. Radiances from the Aqua AMSU-A instrument were also assimilated operationally by NCEP and are included in the "Control". The AIRS Radiance assimilation adds AIRS observed radiance observations for a select set of channels to the data set being assimilated, as done operationally by NCEP. In the AIRS T(p) assimilation, all information used in the Control was assimilated as well as Quality Controlled AIRS Version-5 temperature profiles, i.e., AIRS T(p) information was substituted for AIRS radiance information. The AIRS Version-5 temperature profiles were presented to the GSI analysis as rawinsonde profiles, assimilated down to a case-by-case appropriate pressure level p(sub best) determined using the Quality Control procedure. Version-5 also determines case-by-case, level-by-level error estimates of the temperature profiles, which were used as the uncertainty of each temperature measurement. These experiments using GEOS-5 have shown that forecasts resulting from analyses using the AIRS T(p) assimilation system were superior to those from the Radiance assimilation system, both with regard to global 7 day forecast skill and also the ability to predict storm tracks and intensity.

Risk factors for idiopathic intracranial hypertension in men: a case-control study

PubMed Central

Fraser, J. Alexander; Bruce, Beau B.; Rucker, Janet; Fraser, Lisa-Ann; Atkins, Edward J.; Newman, Nancy J.; Biousse, Valérie

2009-01-01

Objective To identify risk factors for idiopathic intracranial hypertension (IIH) in men Design Case-control study. A 96-item telephone questionnaire, answered retrospectively, with cases recalling at the age of their diagnosis and controls recalling at the age of their corresponding case's diagnosis. Setting Outpatient clinics in two US tertiary care centers Participants The characteristics of 24 men with IIH were compared to those of 48 controls matched for sex, age, race, and World Health Organization body mass index (BMI) category. Main Outcome Measures Two previously validated questionnaires: the ADAM (Androgen Deficiency in Aging Males) questionnaire for testosterone deficiency and the Berlin questionnaire for obstructive sleep apnea (OSA), embedded within the telephone questionnaire. Analysis with Mantel-Haenszel odds ratios and mixed-effects logistic regression models accounted for matching. Results Cases and controls had similar enrollment matching characteristics. Although matching was successful by BMI category, there was a small difference between BMI values of cases and controls (cases: median 31.7, controls: median 29.9; p=0.03). After adjustment by BMI value, men with IIH were significantly more likely than controls to have a positive ADAM questionnaire for testosterone deficiency (OR: 17.4, 95% CI: 5.6-54.5; p<0.001) and significantly more likely to have either a positive Berlin questionnaire for OSA or history of diagnosed OSA (OR: 4.4, 95% CI: 1.5-12.9; p=0.03). Conclusions Men with IIH are more likely than controls to have symptoms associated with testosterone deficiency and OSA. These associations suggest a possible role for sex hormones and OSA in the pathogenesis of IIH in men. PMID:19945715

Experience with multiple control groups in a large population-based case-control study on genetic and environmental risk factors.

PubMed

Pomp, E R; Van Stralen, K J; Le Cessie, S; Vandenbroucke, J P; Rosendaal, F R; Doggen, C J M

2010-07-01

We discuss the analytic and practical considerations in a large case-control study that had two control groups; the first control group consisting of partners of patients and the second obtained by random digit dialling (RDD). As an example of the evaluation of a general lifestyle factor, we present body mass index (BMI). Both control groups had lower BMIs than the patients. The distribution in the partner controls was closer to that of the patients, likely due to similar lifestyles. A statistical approach was used to pool the results of both analyses, wherein partners were analyzed with a matched analysis, while RDDs were analyzed without matching. Even with a matched analysis, the odds ratio with partner controls remained closer to unity than with RDD controls, which is probably due to unmeasured confounders in the comparison with the random controls as well as intermediary factors. However, when studying injuries as a risk factor, the odds ratio remained higher with partner control subjects than with RRD control subjects, even after taking the matching into account. Finally we used factor V Leiden as an example of a genetic risk factor. The frequencies of factor V Leiden were identical in both control groups, indicating that for the analyses of this genetic risk factor the two control groups could be combined in a single unmatched analysis. In conclusion, the effect measures with the two control groups were in the same direction, and of the same order of magnitude. Moreover, it was not always the same control group that produced the higher or lower estimates, and a matched analysis did not remedy the differences. Our experience with the intricacies of dealing with two control groups may be useful to others when thinking about an optimal research design or the best statistical approach.

CASE/A - COMPUTER AIDED SYSTEM ENGINEERING AND ANALYSIS, ECLSS/ATCS SERIES

NASA Technical Reports Server (NTRS)

Bacskay, A.

1994-01-01

Design and analysis of Environmental Control and Life Support Systems (ECLSS) and Active Thermal Control Systems (ATCS) for spacecraft missions requires powerful software that is flexible and responsive to the demands of particular projects. CASE/A is an interactive trade study and analysis tool designed to increase productivity during all phases of systems engineering. The graphics-based command-driven package provides a user-friendly environment in which the engineer can analyze the performance and interface characteristics of an ECLS/ATC system. The package is useful during all phases of a spacecraft design program, from initial conceptual design trade studies to the actual flight, including pre-flight prediction and in-flight anomaly analysis. The CASE/A program consists of three fundamental parts: 1) the schematic management system, 2) the database management system, and 3) the simulation control and execution system. The schematic management system allows the user to graphically construct a system model by arranging icons representing system components and connecting the components with physical fluid streams. Version 4.1 contains 51 fully coded and documented default component routines. New components can be added by the user through the "blackbox" component option. The database management system supports the storage and manipulation of component data, output data, and solution control data through interactive edit screens. The simulation control and execution system initiates and controls the iterative solution process, displaying time status and any necessary diagnostic messages. In addition to these primary functions, the program provides three other important functional areas: 1) model output management, 2) system utility commands, and 3) user operations logic capacity. The model output management system provides tabular and graphical output capability. Complete fluid constituent mass fraction and properties data (mass flow, pressure, temperature, specific heat, density, and viscosity) is generated at user-selected output intervals and stored for reference. The Integrated Plot Utility (IPU) provides plotting capability for all data output. System utility commands are provided to enable the user to operate more efficiently in the CASE/A environment. The user is able to customize a simulation through optional operations FORTRAN logic. This user-developed code is compiled and linked with a CASE/A model and enables the user to control and timeline component operating parameters during various phases of the iterative solution process. CASE/A provides for transient tracking of the flow stream constituents and determination of their thermodynamic state throughout an ECLSS/ATCS simulation, performing heat transfer, chemical reaction, mass/energy balance, and system pressure drop analysis based on user-specified operating conditions. The program tracks each constituent through all combination and decomposition states while maintaining a mass and energy balance on the overall system. This allows rapid assessment of ECLSS designs, the impact of alternate technologies, and impacts due to changes in metabolic forcing functions, consumables usage, and system control considerations. CASE/A is written in FORTRAN 77 for the DEC VAX/VMS computer series, and requires 12Mb of disk storage and a minimum paging file quota of 20,000 pages. The program operates on the Tektronix 4014 graphics standard and VT100 text standard. The program requires a Tektronix 4014 or later graphics terminal, third party composite graphics/text terminal, or personal computer loaded with appropriate VT100/TEK 4014 emulator software. The use of composite terminals or personal computers with popular emulation software is recommended for enhanced CASE/A operations and general ease of use. The program is available on an unlabeled 9-track 6250 BPI DEC VAX BACKUP format magnetic tape. CASE/A development began in 1985 under contract to NASA/Marshall Space Flight Center. The latest version (4.1) was released in 1990. Tektronix and TEK 4014 are trademarks of Tektronix, Inc. VT100 is a trademark of Digital Equipment Corporation.

A mixed-methods evaluation of health-related quality of life for male veterans with and without intestinal stomas.

PubMed

Krouse, Robert S; Grant, Marcia; Wendel, Christopher S; Mohler, M Jane; Rawl, Susan M; Baldwin, Carol M; Coons, Stephen Joel; McCorkle, Ruth; Ko, Clifford Y; Schmidt, C Max

2007-12-01

Intestinal stomas have a major impact on Cases' lives. It is essential to better understand the areas in which interventions may help to minimize the negative consequences. This was a case-control survey study using validated instruments (City of Hope Quality of Life-Ostomy and Short Form 36 for Veterans). Cases were accrued from Veterans Affairs Medical Centers in Tucson, Indianapolis, and Los Angeles. Eligibility included a major intra-abdominal surgical procedure that led to an ostomy (cases), or a similar procedure that did not mandate a stoma (controls). Analysis included quantitative and qualitative responses. The response rate was 48 percent (511/1,063). Cases and controls had relatively similar demographic characteristics. Because of low numbers of female respondents (13 cases and 11 controls), only results for males are reported. Based on both the City of Hope Quality of Life-Ostomy and Short Form 36 for Veterans, cases reported significantly poorer scores on scales/domains reflecting psychologic and social functioning and well being. Additionally, cases reported poorer scores on Short Form 36 for Veterans scales reflecting physical functioning and significantly lower scores on multiple items in the social domain of the City of Hope Quality of Life-Ostomy compared with controls. Two-thirds of cases replied to an open-ended question on their "greatest challenge" related to their ostomy, which led to further clarification of major issues. Multiple health-related quality of life problems were reported by male veterans with intestinal stomas. The greatest differences between cases and controls were observed in the social and psychologic domains/scales. Findings from this study provide a greater understanding of the challenges faced by ostomates and will inform the development and evaluation of urgently needed intervention strategies.

Serum and saliva magnesium in postmenopausal women with xerostomia.

PubMed

Agha-Hosseini, F; Mirzaii-Dizgah, I

2012-10-01

The aim of this study was to investigate serum, stimulated and unstimulated salivary magnesium in postmenopausal women with xerostomia. A case-control study was carried out on 60 selected postmenopausal women aged 41-77 years with or without xerostomia (30 as cases with xerostomia and 30 as controls without xerostomia), conducted at the Clinic of Oral Medicine, Tehran University of Medical Sciences. Unstimulated and paraffin-stimulated saliva samples were obtained by expectoration. Magnesium concentration was determined by the spectrophotometer method. Statistical analysis was carried out using Student's t-test. The mean serum concentration, but not stimulated and unstimulated whole saliva magnesium concentrations, was significantly higher in the cases than in the controls. Serum magnesium level appears to be associated with xerostomia in menopause.

A modified case-control study of cryptosporidiosis (using non-Cryptosporidium-infected enteric cases as controls) in a community setting.

PubMed

Pintar, K D M; Pollari, F; Waltner-Toews, D; Charron, D F; McEwen, S A; Fazil, A; Nesbitt, A

2009-12-01

Data from the first sentinel site (Waterloo Region, Ontario) of the Canadian Integrated Enteric Disease Surveillance System (C-EnterNet) were used in a secondary-based case-control study of laboratory-confirmed Cryptosporidium infections to study the role of various exposure factors. The incidence of cryptosporidiosis in Waterloo Region was almost double both the provincial and national rates. Persons ill with one of nine other enteric infections (amoebiasis, campylobacteriosis, cyclosporiasis, giardiasis, listeriosis, salmonellosis, shigellosis, verotoxigenic E. coli infections, yersiniosis) captured by the surveillance system were used as the control group. Of 1204 cases of enteric illness in the sentinel area between April 2005 and December 2007, 36 cases and 803 controls were selected after excluding outbreak and international travel-related cases. Univariable analyses (Pearson chi2 and Fisher's exact tests) and multivariable logistic regression were performed. Results of the multivariable analysis found that cryptosporidiosis was associated with swimming in a lake or river (OR 2.9, 95% CI 1.2-7.4), drinking municipal water (a potential surrogate for urban respondents vs. rural) (OR 2.4, 95% CI 1.04-5.7), and having a family member with a diarrhoeal illness (OR 2.9, 95% CI 1.3-6.4).

Outbreak of Salmonella Enteritidis phage type 13a: case-control investigation in Hertsmere, United Kingdom.

PubMed

Morgan, O; Milne, L; Kumar, S; Murray, D; Man, W; Georgiou, M; Verlander, N Q; de Pinna, E; McEvoy, M

2007-07-01

Cases of illness were reported to Hertsmere Borough Council among attendees of a children's charity event in June 2006. Initial laboratory investigation identified Salmonella Enteritidis PT13a as a possible cause of the outbreak. We carried out an unmatched case-control investigation. The population at risk included all individuals who attended the event. Self-completion questionnaires were sent to 53 presumptive cases and 212 randomly selected potential controls. Information was available for 49 cases and 128 controls (overall response rate=75%). We calculated odds ratios from single and multivariable analysis and tested for all two-way interactions. Risk factors for diarrhoea were eating egg mayonnaise bagels (OR=34.1, 95%CI 10.5 - 111.3) and drinking apple juice (OR=16.1, 95% CI 3.5 - 74.2). There was weak statistical evidence to suggest that the risk of diarrhoea after eating egg mayonnaise bagels was greater in the afternoon. No food samples were available to confirm which food item might have caused this outbreak. Eggs from Spain were used by the caterer. The ecology of salmonella, experience from previous outbreaks and epidemiological findings from this case-control investigation suggest that the most likely cause of the outbreak was contaminated eggs.

Risk factors and outcomes of carbapenem-resistant Acinetobacter baumannii ventilator-associated pneumonia in the neonate: A case-case-control study.

PubMed

Thatrimontrichai, Anucha; Techato, Chirabat; Dissaneevate, Supaporn; Janjindamai, Waricha; Maneenil, Gunlawadee; Kritsaneepaiboon, Supika; Tanaanantarak, Pattama

2016-07-01

Carbapenem-resistant and susceptible Acinetobacter baumannii (CRAB and CSAB) have emerged as serious threats among critically ill neonates. We aimed to identify the risks and outcomes for CRAB and CSAB ventilator-associated pneumonia (VAP) compared with a control group. We performed a retrospective and case-case-control study in a neonatal intensive care unit between 2009 and 2014. The numbers of patients in the CRAB VAP, CSAB VAP, and control groups were 63, 13, and 25, respectively. The mean gestational ages and median birthweights of CRAB VAP, CSAB VAP, and control groups were 33.2, 35.0, and 32.6 weeks and 1800, 2230, and 2245 g, respectively. By multivariate analysis, infants who had a birthweight of 1000-1499 g (P = 0.04), cesarean section (P = 0.01), history of cephalosporin use (P = 0.02), and surfactant replacement (P = 0.01) in CRAB VAP were significantly higher than in the control group. Inborn infant (P = 0.01), reintubation (P = 0.04), and umbilical artery catheterization (P = 0.04) in the CRAB VAP group were significantly more than in the CSAB VAP group. The crude mortality rates (CMRs) of CRAB VAP and CSAB VAP were 15.9% and 7.7%, respectively. By univariate analysis, the CMR, septic shock, and bronchopulmonary dysplasia in CRAB VAP were higher than in the control group. There are very high mortality and short-term morbidity rates in CRAB VAP. Surfactant replacement therapy, fewer cesarean sections, and the reduced use of cephalosporin in very preterm infants may reduce CRAB VAP. Copyright © 2016 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Cumulative Small Effect Genetic Markers and the Risk of Colorectal Cancer in Poland, Estonia, Lithuania, and Latvia

PubMed Central

Serrano-Fernandez, Pablo; Dymerska, Dagmara; Kurzawski, Grzegorz; Derkacz, Róża; Sobieszczańska, Tatiana; Banaszkiewicz, Zbigniew; Roomere, Hanno; Oitmaa, Eneli; Metspalu, Andres; Janavičius, Ramūnas; Elsakov, Pavel; Razumas, Mindaugas; Petrulis, Kestutis; Irmejs, Arvīds; Miklaševičs, Edvīns; Scott, Rodney J.; Lubiński, Jan

2015-01-01

The continued identification of new low-penetrance genetic variants for colorectal cancer (CRC) raises the question of their potential cumulative effect among compound carriers. We focused on 6 SNPs (rs380284, rs4464148, rs4779584, rs4939827, rs6983267, and rs10795668), already described as risk markers, and tested their possible independent and combined contribution to CRC predisposition. Material and Methods. DNA was collected and genotyped from 2330 unselected consecutive CRC cases and controls from Estonia (166 cases and controls), Latvia (81 cases and controls), Lithuania (123 cases and controls), and Poland (795 cases and controls). Results. Beyond individual effects, the analysis revealed statistically significant linear cumulative effects for these 6 markers for all samples except of the Latvian one (corrected P value = 0.018 for the Estonian, corrected P value = 0.0034 for the Lithuanian, and corrected P value = 0.0076 for the Polish sample). Conclusions. The significant linear cumulative effects demonstrated here support the idea of using sets of low-risk markers for delimiting new groups with high-risk of CRC in clinical practice that are not carriers of the usual CRC high-risk markers. PMID:26101521

Cumulative Small Effect Genetic Markers and the Risk of Colorectal Cancer in Poland, Estonia, Lithuania, and Latvia.

PubMed

Serrano-Fernandez, Pablo; Dymerska, Dagmara; Kurzawski, Grzegorz; Derkacz, Róża; Sobieszczańska, Tatiana; Banaszkiewicz, Zbigniew; Roomere, Hanno; Oitmaa, Eneli; Metspalu, Andres; Janavičius, Ramūnas; Elsakov, Pavel; Razumas, Mindaugas; Petrulis, Kestutis; Irmejs, Arvīds; Miklaševičs, Edvīns; Scott, Rodney J; Lubiński, Jan

2015-01-01

The continued identification of new low-penetrance genetic variants for colorectal cancer (CRC) raises the question of their potential cumulative effect among compound carriers. We focused on 6 SNPs (rs380284, rs4464148, rs4779584, rs4939827, rs6983267, and rs10795668), already described as risk markers, and tested their possible independent and combined contribution to CRC predisposition. Material and Methods. DNA was collected and genotyped from 2330 unselected consecutive CRC cases and controls from Estonia (166 cases and controls), Latvia (81 cases and controls), Lithuania (123 cases and controls), and Poland (795 cases and controls). Results. Beyond individual effects, the analysis revealed statistically significant linear cumulative effects for these 6 markers for all samples except of the Latvian one (corrected P value = 0.018 for the Estonian, corrected P value = 0.0034 for the Lithuanian, and corrected P value = 0.0076 for the Polish sample). Conclusions. The significant linear cumulative effects demonstrated here support the idea of using sets of low-risk markers for delimiting new groups with high-risk of CRC in clinical practice that are not carriers of the usual CRC high-risk markers.

Modeling malaria control intervention effect in KwaZulu-Natal, South Africa using intervention time series analysis.

PubMed

Ebhuoma, Osadolor; Gebreslasie, Michael; Magubane, Lethumusa

The change of the malaria control intervention policy in South Africa (SA), re-introduction of dichlorodiphenyltrichloroethane (DDT), may be responsible for the low and sustained malaria transmission in KwaZulu-Natal (KZN). We evaluated the effect of the re-introduction of DDT on malaria in KZN and suggested practical ways the province can strengthen her already existing malaria control and elimination efforts, to achieve zero malaria transmission. We obtained confirmed monthly malaria cases in KZN from the malaria control program of KZN from 1998 to 2014. The seasonal autoregressive integrated moving average (SARIMA) intervention time series analysis (ITSA) was employed to model the effect of the re-introduction of DDT on confirmed monthly malaria cases. The result is an abrupt and permanent decline of monthly malaria cases (w 0 =-1174.781, p-value=0.003) following the implementation of the intervention policy. The sustained low malaria cases observed over a long period suggests that the continued usage of DDT did not result in insecticide resistance as earlier anticipated. It may be due to exophagic malaria vectors, which renders the indoor residual spraying not totally effective. Therefore, the feasibility of reducing malaria transmission to zero in KZN requires other reliable and complementary intervention resources to optimize the existing ones. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Cadmium exposure and risk of lung cancer: a meta-analysis of cohort and case-control studies among general and occupational populations.

PubMed

Chen, Cheng; Xun, Pengcheng; Nishijo, Muneko; He, Ka

2016-09-01

The association between cadmium exposure and risk of lung cancer is still unclear. We quantitatively reviewed the observational studies that investigated the association between cadmium exposure and lung cancer risk in both general and occupational populations published through April 2015. The final data set is comprised of three cohort studies in the general population totaling 22,551 participants (354 events) with a mean follow-up of 15 years, five occupational cohort studies including 4205 individuals (180 events) with an average follow-up of 31 years, and three occupational case-control studies including 4740 cases and 6268 controls. Comparing the highest to the lowest category of cadmium exposure, the weighted relative risk and 95% confidence interval of lung cancer in the general population was 1.42 (95% CI (0.91, 2.23)); the weighted risk estimates (95% CIs) of lung cancer in three occupational cohort studies and three case-control studies were 0.68 (95% CI (0.33, 1.41)) and 1.61 (95% CI (0.94, 2.75)), respectively. No linear association was found. When comparing participants exposed to cadmium with non-exposed based on available data, the association became statistically significant. According to findings from this meta-analysis, the possibility that cadmium exposure may increase risk of lung cancer cannot be completely ruled out in either general or occupational population.

Association of COL1A1 polymorphism with high myopia: a Meta-analysis

PubMed Central

Jin, Guang-Ming; Zhao, Xiao-Jing; Chen, Ai-Ming; Chen, Yong-Xing; Li, Qin

2016-01-01

AIM To investigate the association between collagen type I alpha 1 (COL1A1) gene and high myopia. METHODS In this Meta-analysis, we examined 5 published case-control studies that involved 1942 high myopia cases and 2929 healthy controls to assess the association between the COL1A1 rs2075555 polymorphism and high myopia risk. We calculated the pooled odds ratios (ORs) of COL1A1 rs2075555 polymorphism in high myopia cases vs healthy controls to evaluate the strength of the association. RESULTS Overall, there was no significant difference both in the genotype and allele distributions of COL1A1 rs2075555 polymorphism between high myopia cases and healthy controls: CC vs AA OR=1.10, 95% confidence interval (CI)=0.76-1.58; AC vs AA OR=0.98, 95%CI 0.80-1.20; CC/AC vs AA/OR=1.01, 95%CI 0.84-1.22; CC vs AC/AA OR=1.06, 95%CI=0.93-1.20; C vs A OR=1.06, 95%CI 0.91-1.23). In addition, in the stratified analyses by ethnicity, no significant associations were found in any genetic model both in European and Asia cohorts. CONCLUSION Our results indicate that the COL1A1 rs2075555 polymorphism may not affect susceptibility to high myopia. PMID:27162737

Lifetime Physical Activity and Breast Cancer: a Case-Control Study in Kelantan, Malaysia.

PubMed

Yen, Siew Hwa; Knight, A; Krishna, Mbv; Muda, Wmw; Rufai, Aa

2016-01-01

Physical inactivity has been identified as the fourth leading risk factor for global mortality and is associated with increased breast cancer diagnosis and recurrence. To examine the association between adult lifetime physical activity and breast cancer risk in a case-control analysis. This study involved 122 cases of breast cancer and 121 controls in the state of Kelantan in Malaysia. A comprehensive measure of lifetime physical activity was used to assess occupational, household, and recreational/sports activity. For every type of activity, a metabolic equivalent (MET) score was assigned using the compendium of physical activities. MET-hours/week per year for all types of activities at different levels of intensities for different age groups were calculated. Logistic regression analysis was used to estimate odds ratios between various measures of physical activity and breast cancer risk. The mean MET-hours/week per year for all activities were 120.0 and 132.9 of MET-hours/week per year for cases and controls respectively. Household activities accounted for about 70% of the total lifetime physical activities. Only about 2.5% of the total lifetime physical activities were in the form of recreational/sports. This study found no association between lifetime occupational and recreational/sports physical activities with breast cancer risk among Kelantanese women. However, higher intensity lifetime household activities seemed to significantly reduce risk of breast cancer.

Vaccination history and risk of childhood leukaemia.

PubMed

Ma, Xiaomei; Does, Monique B; Metayer, Catherine; Russo, Carolyn; Wong, Alan; Buffler, Patricia A

2005-10-01

Previous studies on vaccination and childhood leukaemia generated inconsistent results. In the Northern California Childhood Leukaemia Study, a case-control study with incident cases and matched birth certificate controls, detailed written vaccination records were collected. A total of 323 cases aged 0-14 years at diagnosis and 409 controls were included in this analysis. All vaccinations were censored on the reference date (date of diagnosis for cases and the corresponding date for matched controls). Conditional logistic regression analysis was conducted, adjusting for potential confounding factors. A primary variable of interest is the number of administrations (doses) of various types of vaccines. Vaccinations against diphtheria, pertussis, tetanus, poliomyelitis, measles, mumps, and rubella were not associated with the risk of leukaemia. The odds ratio for each dose of Haemophilus influenzae type b (Hib) vaccine was 0.81 (95% CI 0.68-0.96). Compared with children who received two or fewer doses of Hib vaccine, those who received three or more doses had a significantly reduced risk of childhood leukaemia (odds ratio = 0.55, 95% confidence interval 0.32-0.94). The number of doses of hepatitis B vaccine received was not associated with leukaemia risk. Hib vaccination is associated with a reduced risk of childhood leukaemia. Future studies with detailed exposure assessment and large sample sizes are needed to further address the role of vaccinations in the etiology of childhood leukaemia.

Genetic risk factors for ovarian cancer and their role for endometriosis risk.

PubMed

Burghaus, Stefanie; Fasching, Peter A; Häberle, Lothar; Rübner, Matthias; Büchner, Kathrin; Blum, Simon; Engel, Anne; Ekici, Arif B; Hartmann, Arndt; Hein, Alexander; Beckmann, Matthias W; Renner, Stefan P

2017-04-01

Several genetic variants have been validated as risk factors for ovarian cancer. Endometriosis has also been described as a risk factor for ovarian cancer. Identifying genetic risk factors that are common to the two diseases might help improve our understanding of the molecular pathogenesis potentially linking the two conditions. In a hospital-based case-control analysis, 12 single nucleotide polymorphisms (SNPs), validated by the Ovarian Cancer Association Consortium (OCAC) and the Collaborative Oncological Gene-environment Study (COGS) project, were genotyped using TaqMan® OpenArray™ analysis. The cases consisted of patients with endometriosis, and the controls were healthy individuals without endometriosis. A total of 385 cases and 484 controls were analyzed. Odds ratios and P values were obtained using simple logistic regression models, as well as from multiple logistic regression models with adjustment for clinical predictors. rs11651755 in HNF1B was found to be associated with endometriosis in this case-control study. The OR was 0.66 (95% CI, 0.51 to 0.84) and the P value after correction for multiple testing was 0.01. None of the other genotypes was associated with a risk for endometriosis. As rs11651755 in HNF1B modified both the ovarian cancer risk and also the risk for endometriosis, HNF1B may be causally involved in the pathogenetic pathway leading from endometriosis to ovarian cancer. Copyright © 2017 Elsevier Inc. All rights reserved.

Protective efficacy of BCG against leprosy in São Paulo.

PubMed

Lombardi, C; Pedrazzani, E S; Pedrazzani, J C; Filho, P F; Zicker, F

1996-03-01

The case-control study reported here evaluated the protective effect of BCG vaccine against leprosy in São Paulo, Brazil. Seventy-eight patients under age 16 who had been diagnosed as having leprosy (cases) and 385 healthy individuals (controls) were selected and matched by sex, age, place of residence, and type of exposure to leprosy (intradomiciliary or extradomiciliary). The cases were drawn from an active patient registry and from a group of new leprosy cases treated at 50 health centers in the cities of Bauru and Ribeirão Preto in the state of São Paulo. In order to estimate the protective effect of BCG, the prevalences of BCG scars in cases and controls were compared. The presence of one or more scars was associated with an estimated protective efficacy of 90% (95% confidence interval: 78% to 96%). Stratified analysis by age group, sex, socioeconomic level, and clinical form of the disease revealed no significant differences in the protection provided by the vaccine. However, it seems clear that more data will be needed in order to accurately assess the true relevance of BCG for leprosy control programs.

Modified metabolic syndrome and second cancers in women: A case control study.

PubMed

Ortiz-Mendoza, Carlos-Manuel; Pérez-Chávez, Ernesto; Fuente-Vera, Tania-Angélica De-la

2016-01-01

According to some studies, the metabolic syndrome causes diverse primary cancers; however, there is no evidence about metabolic syndrome impact on second cancers development in women. To find out the implication of the modified metabolic syndrome in women with second cancers. This was a case-control study, at a general hospital in Mexico City, in women with second cancers (cases) and age-matched women with only one neoplasm (controls). The analysis comprised: Tumor (s), anthropometric features, and body mass index (BMI); moreover, presence of diabetes mellitus, hypertension, and fasting serum levels of total cholesterol, triglycerides and glucose. The sample was of nine cases and 27 controls. In cases, the metabolic syndrome (diabetes mellitus or glucose > 99 mg/dL + hypertension or blood pressure ≥ 135/85 mm Hg + triglycerides > 149 mg/dL or BMI ≥ 30 kg/m 2 ) was more frequent (odds ratio 20.8, 95% confidence interval: 1.9-227.1). Our results suggest that in women, the modified metabolic syndrome may be a risk factor for second cancers.

Overall survival and clinical characteristics of BRCA mutation carriers with stage I/II pancreatic cancer.

PubMed

Golan, Talia; Sella, Tal; O'Reilly, Eileen M; Katz, Matthew H G; Epelbaum, Ron; Kelsen, David P; Borgida, Ayelet; Maynard, Hannah; Kindler, Hedy; Friedmen, Eitan; Javle, Milind; Gallinger, Steven

2017-03-14

BRCA1/BRCA2 germ line (GL) mutation carriers with pancreatic adenocarcinoma (PDAC) may have distinct outcomes. We recently described an apparent more favourable prognosis of surgically resected BRCA-associated PDAC patients in a single-arm, uncontrolled, retrospective study. However, the prognostic impact of GL BRCA1/2 mutations in surgically resected PDAC has not been compared with a matched control population. A larger multi-centre, case-control retrospective analysis was performed. Cases were patients with surgically resected, BRCA1/2-associated PDAC from 2004 to 2013. Controls included surgically resected PDAC cases treated during the same time period that were either BRCA non-carriers, or had no family history of breast, ovarian or pancreatic cancers. Cases and controls were matched by: age at diagnosis (within ±5-year period) and institution. Demographics, clinical history, overall survival (OS) and disease-free survival (DFS) were abstracted from patient records. Statistical comparisons were assessed using χ 2 - and Fisher's exact test, and median DFS/OS using Kaplan-Meier method and log-rank testing. Twenty-five patients with BRCA1-(n=4) or BRCA2 (N=21)-associated resectable PDAC were identified. Mean age was 55.7 years (range, 34-78 years), 48% (n=12) were females and 76% (n=19) were Jewish. Cases were compared (1 : 2) with 49 resectable PDAC controls, and were balanced for age, ethnicity and other relevant clinical and pathological features. BRCA-associated PDAC patients received neoadjuvant, or adjuvant platinum-based treatment more frequently than controls (7 out of 8 vs 6 out of 14) and (7 out of 21 vs 3 out of 44), respectively. No significant difference in median OS (37.06 vs 38.77 months, P=0.838) and in DFS (14.3 vs 12.0 months, P=0.303) could be demonstrated between cases and controls. A trend to increased DFS was observed among BRCA-positive cases treated with neoadjuvant/adjuvant platinum-containing regimens (n=10) compared with similarly treated controls (n=7) (39.1 vs 12.4 months, P=0.255). In this retrospective analysis, the prognosis of surgically resectable BRCA-associated PDAC is no different than that of sporadic PDAC from the same institution. The role of platinum-based adjuvant therapy in this setting requires prospective investigation.

Safety of Mixed Model Access Control in a Multilevel System

DTIC Science & Technology

2014-06-01

SOFTWARE ENGINEERING from the NAVAL POSTGRADUATE SCHOOL June 2014 Author: Randall J. Arvay Approved by: James Bret Michael Dan C . Boger...5  B.  HYPOTHESIS..................................................................................................7  C .  BACKGROUND...27  C .  USE CASE ANALYSIS .................................................................................30  1.  Use Case

The rare TREM2 R47H variant exerts only a modest effect on Alzheimer disease risk.

PubMed

Hooli, Basavaraj V; Parrado, Antonio R; Mullin, Kristina; Yip, Wai-Ki; Liu, Tian; Roehr, Johannes T; Qiao, Dandi; Jessen, Frank; Peters, Oliver; Becker, Tim; Ramirez, Alfredo; Lange, Christoph; Bertram, Lars; Tanzi, Rudolph E

2014-10-07

Recently, 2 independent studies reported that a rare missense variant, rs75932628 (R47H), in exon 2 of the gene encoding the "triggering receptor expressed on myeloid cells 2" (TREM2) significantly increases the risk of Alzheimer disease (AD) with an effect size comparable to that of the APOE ε4 allele. In this study, we attempted to replicate the association between rs75932628 and AD risk by directly genotyping rs75932628 in 2 independent Caucasian family cohorts consisting of 927 families (with 1,777 affected and 1,235 unaffected) and in 2 Caucasian case-control cohorts composed of 1,314 cases and 1,609 controls. In addition, we imputed genotypes in 3 independent Caucasian case-control cohorts containing 1,906 cases and 1,503 controls. Meta-analysis of the 2 family-based and the 5 case-control cohorts yielded a p value of 0.0029, while the overall summary estimate (using case-control data only) resulted in an odds ratio of 1.67 (95% confidence interval 0.95-2.92) for the association between the TREM2 R47H and increased AD risk. While our results serve to confirm the association between R47H and risk of AD, the observed effect on risk was substantially smaller than that previously reported. © 2014 American Academy of Neurology.

The rare TREM2 R47H variant exerts only a modest effect on Alzheimer disease risk

PubMed Central

Hooli, Basavaraj V.; Parrado, Antonio R.; Mullin, Kristina; Yip, Wai-Ki; Liu, Tian; Roehr, Johannes T.; Qiao, Dandi; Jessen, Frank; Peters, Oliver; Becker, Tim; Ramirez, Alfredo; Lange, Christoph; Bertram, Lars

2014-01-01

Objectives: Recently, 2 independent studies reported that a rare missense variant, rs75932628 (R47H), in exon 2 of the gene encoding the “triggering receptor expressed on myeloid cells 2” (TREM2) significantly increases the risk of Alzheimer disease (AD) with an effect size comparable to that of the APOE ε4 allele. Methods: In this study, we attempted to replicate the association between rs75932628 and AD risk by directly genotyping rs75932628 in 2 independent Caucasian family cohorts consisting of 927 families (with 1,777 affected and 1,235 unaffected) and in 2 Caucasian case-control cohorts composed of 1,314 cases and 1,609 controls. In addition, we imputed genotypes in 3 independent Caucasian case-control cohorts containing 1,906 cases and 1,503 controls. Results: Meta-analysis of the 2 family-based and the 5 case-control cohorts yielded a p value of 0.0029, while the overall summary estimate (using case-control data only) resulted in an odds ratio of 1.67 (95% confidence interval 0.95–2.92) for the association between the TREM2 R47H and increased AD risk. Conclusions: While our results serve to confirm the association between R47H and risk of AD, the observed effect on risk was substantially smaller than that previously reported. PMID:25186855

Continuing use of antithrombotic medications for patients with bleeding gastroduodenal ulcer requiring endoscopic hemostasis: a case-control study.

PubMed

Kawasaki, Keisuke; Nakamura, Shotaro; Kurahara, Koichi; Nagasue, Tomohiro; Yanai, Shunichi; Harada, Akira; Yaita, Hiroki; Fuchigami, Tadahiko; Matsumoto, Takayuki

2017-09-01

The aim of this study was to compare clinical characteristics and outcomes of bleeding gastroduodenal ulcer between patients taking antithrombotic medications and those not taking antithrombotic medications. We performed a case-control study of 346 patients with endoscopically verified bleeding gastroduodenal ulcer, which included 173 cases taking antithrombotic medications throughout peri-bleeding period and 173 age- and sex-matched controls not taking antithrombotic medications. The cases showed less frequent Helicobacter pylori (H. pylori) infections (45.1% versus 60.7%, p = .005), more frequent duodenal location (31.8% versus 19.1%, p = .009), and more frequent rebleeding (13.9% versus 5.8%, p = .02) than the controls. Multivariate analysis revealed that duodenal location (odds ratio [OR] 3.01, 95% confidence interval [CI] 1.37-6.65) and use of antithrombotic medications (OR 2.47, 95% CI 1.13-5.77) were independent factors for rebleeding. However, there were no differences in clinical outcomes, including final successful endoscopic hemostasis, need for surgical intervention, and mortality between cases and controls. Thromboembolic events did not occur in any cases and controls during the periendoscopic period. Low prevalence of H. pylori infection, frequent duodenal location, and high rebleeding rate are characteristics of patients with bleeding gastroduodenal ulcer under antithrombotic medications. Continuation of antithrombotic medications can be accepted for bleeding gastroduodenal ulcer.

Effect of HCV on fasting glucose, fasting insulin and peripheral insulin resistance in first 5 years of infection.

PubMed

Ahmed, Naeema; Rashid, Amir; Naveed, Abdul Khaliq; Bashir, Qudsia

2016-02-01

To assess the effects of hepatitis C virus infection in the first 5 years on fasting glucose, fasting insulin and peripheral insulin resistance. The case-control study was conducted at the Army Medical College, Rawalpindi, from December 2011 to November 2012, and comprised subjects recruited from a government hospital in Rawalpindi. The subjects included known cases of hepatitis C virus infection for at least 5 years, and normal healthy controls. Fasting blood samples of all the subjects were collected and analysed for serum fasting insulin and serum fasting glucose levels. Homeostatic model assessment-Insulin resistance was calculated SPSS 11 was used for statistical analysis. Of the 30 subjects, 20(66.6%) were cases, while 10(33.3%) were controls. Serum fasting glucose mean level in cases was 89.55±9.53 compared to 84.40±9.80 in the controls (p=0.188). The mean serum fasting insulin in controls was 7.52±3.23 and 6.79±3.30 in cases (p=0.567). Homeostatic model assessment-Insulin resistance level in controls was 1.60±0.76 and In the cases it was 1.49±0.74 (p=0.695). Peripheral insulin resistance and development of type 2 diabetes as a complication of hepatitis C virus infection was not likely at least within the first five years of infection.

A Case of Error Disclosure: A Communication Privacy Management Analysis

PubMed Central

Petronio, Sandra; Helft, Paul R.; Child, Jeffrey T.

2013-01-01

To better understand the process of disclosing medical errors to patients, this research offers a case analysis using Petronios’s theoretical frame of Communication Privacy Management (CPM). Given the resistance clinicians often feel about error disclosure, insights into the way choices are made by the clinicians in telling patients about the mistake has the potential to address reasons for resistance. Applying the evidenced-based CPM theory, developed over the last 35 years and dedicated to studying disclosure phenomenon, to disclosing medical mistakes potentially has the ability to reshape thinking about the error disclosure process. Using a composite case representing a surgical mistake, analysis based on CPM theory is offered to gain insights into conversational routines and disclosure management choices of revealing a medical error. The results of this analysis show that an underlying assumption of health information ownership by the patient and family can be at odds with the way the clinician tends to control disclosure about the error. In addition, the case analysis illustrates that there are embedded patterns of disclosure that emerge out of conversations the clinician has with the patient and the patient’s family members. These patterns unfold privacy management decisions on the part of the clinician that impact how the patient is told about the error and the way that patients interpret the meaning of the disclosure. These findings suggest the need for a better understanding of how patients manage their private health information in relationship to their expectations for the way they see the clinician caring for or controlling their health information about errors. Significance for public health Much of the mission central to public health sits squarely on the ability to communicate effectively. This case analysis offers an in-depth assessment of how error disclosure is complicated by misunderstandings, assuming ownership and control over information, unwittingly following conversational scripts that convey misleading messages, and the difficulty in regulating privacy boundaries in the stressful circumstances that occur with error disclosures. As a consequence, the potential contribution to public health is the ability to more clearly see the significance of the disclosure process that has implications for many public health issues. PMID:25170501

Genome-wide association study of preeclampsia detects novel maternal single nucleotide polymorphisms and copy-number variants in subsets of the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) study cohort

PubMed Central

Zhao, Linlu; Bracken, Michael B.; DeWan, Andrew T.

2013-01-01

Summary A genome-wide association study was undertaken to identify maternal single nucleotide polymorphisms (SNPs) and copy-number variants (CNVs) associated with preeclampsia. Case-control analysis was performed on 1070 Afro-Caribbean (n=21 cases and 1049 controls) and 723 Hispanic (n=62 cases and 661 controls) mothers and 1257 mothers of European ancestry (n=50 cases and 1207 controls) from the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) study. European ancestry subjects were genotyped on Illumina Human610-Quad and Afro-Caribbean and Hispanic subjects were genotyped on Illumina Human1M-Duo BeadChip microarrays. Genome-wide SNP data were analyzed using PLINK. CNVs were called using three detection algorithms (GNOSIS, PennCNV, and QuantiSNP), merged using CNVision, and then screened using stringent criteria. SNP and CNV findings were compared to those of the Study of Pregnancy Hypertension in Iowa (SOPHIA), an independent preeclampsia case-control dataset of Caucasian mothers (n=177 cases and 116 controls). A list of top SNPs were identified for each of the HAPO ethnic groups, but none reached Bonferroni-corrected significance. Novel candidate CNVs showing enrichment among preeclampsia cases were also identified in each of the three ethnic groups. Several variants were suggestively replicated in SOPHIA. The discovered SNPs and copy-number variable regions present interesting candidate genetic variants for preeclampsia that warrant further replication and investigation. PMID:23551011

Estimating the influenza vaccine effectiveness against medically attended influenza in clinical settings: a hospital-based case-control study with a rapid diagnostic test in Japan.

PubMed

Suzuki, Motoi; Yoshimine, Hiroyuki; Harada, Yoshitaka; Tsuchiya, Naho; Shimada, Ikumi; Ariyoshi, Koya; Inoue, Kenichiro

2013-01-01

Influenza vaccine effectiveness (VE) studies are usually conducted by specialized agencies and require time and resources. The objective of this study was to estimate the influenza VE against medically attended influenza using a test-negative case-control design with rapid influenza diagnostic tests (RIDT) in a clinical setting. A prospective study was conducted at a community hospital in Nagasaki, western Japan during the 2010/11 influenza season. All outpatients aged 15 years and older with influenza-like illnesses (ILI) who had undergone RIDT were enrolled. A test-negative case-control design was applied to estimate the VEs: the cases were ILI patients with positive RIDT results and the controls were ILI patients with negative RIDT results. Information on patient characteristics, including vaccination histories, was collected using questionnaires and medical records. Between December 2010 and April 2011, 526 ILI patients were tested with RIDT, and 476 were eligible for the analysis. The overall VE estimate against medically attended influenza was 47.6%, after adjusting for the patients' age groups, presence of chronic conditions, month of visit, and smoking and alcohol use. The seasonal influenza vaccine reduced the risk of medically attended influenza by 60.9% for patients less than 50 years of age, but a significant reduction was not observed for patients 50 years of age and older. A sensitivity analysis provided similar figures. The test-negative case-control study using RIDT provided moderate influenza VE consistent with other reports. Utilizing the commonly used RIDT to estimate VE provides rapid assessment of VE; however, it may require validation with more specific endpoint.

Identification of patients with gout: elaboration of a questionnaire for epidemiological studies.

PubMed

Richette, P; Clerson, P; Bouée, S; Chalès, G; Doherty, M; Flipo, R M; Lambert, C; Lioté, F; Poiraud, T; Schaeverbeke, T; Bardin, T

2015-09-01

In France, the prevalence of gout is currently unknown. We aimed to design a questionnaire to detect gout that would be suitable for use in a telephone survey by non-physicians and assessed its performance. We designed a 62-item questionnaire covering comorbidities, clinical features and treatment of gout. In a case-control study, we enrolled patients with a history of arthritis who had undergone arthrocentesis for synovial fluid analysis and crystal detection. Cases were patients with crystal-proven gout and controls were patients who had arthritis and effusion with no monosodium urate crystals in synovial fluid. The questionnaire was administered by phone to cases and controls by non-physicians who were unaware of the patient diagnosis. Logistic regression analysis and classification and regression trees were used to select items discriminating cases and controls. We interviewed 246 patients (102 cases and 142 controls). Two logistic regression models (sensitivity 88.0% and 87.5%; specificity 93.0% and 89.8%, respectively) and one classification and regression tree model (sensitivity 81.4%, specificity 93.7%) revealed 11 informative items that allowed for classifying 90.0%, 88.8% and 88.5% of patients, respectively. We developed a questionnaire to detect gout containing 11 items that is fast and suitable for use in a telephone survey by non-physicians. The questionnaire demonstrated good properties for discriminating patients with and without gout. It will be administered in a large sample of the general population to estimate the prevalence of gout in France. 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.

Caries Experience in Children with and without Molar-Incisor Hypomineralisation: A Case-Control Study.

PubMed

Grossi, Juliana de Aguiar; Cabral, Renata Nunes; Leal, Soraya Coelho

2017-01-01

The aim of this study was to compare the caries experience of children with and without molar-incisor hypomineralisation (MIH). A case-control study was designed in which 130 children aged between 7 and 13 years with MIH (cases) were matched with 130 children without the condition (controls) according to age, sex, and school. Dental caries and MIH were assessed using the Caries Assessment Spectrum and Treatment (CAST) and European Academy of Paediatric Dentistry (EAPD) criteria, respectively, by three examiners. CAST was converted into DMFT/dmft; the Kruskal-Wallis test was performed to analyse whether dmft/DMFT was influenced by the severity of MIH. Associations between MIH and dental caries were analysed at child and tooth levels: between and within subjects, respectively. To correlate MIH severity and the occurrence of dental caries, the Cochran-Armitage test was used. The mean age of the children was 9.63 ± 1.29 years. The mean dmft for cases was 1.23 ± 1.99 and for controls 1.71 ± 2.22 (p > 0.05). For the DMFT, the mean scores for cases and controls were 0.45 ± 0.90 and 0.07 ± 0.25, respectively (p < 0.001). The between-subject analysis showed no difference in relation to enamel carious lesions; however, the prevalence of dentine carious lesions was significantly higher in children with MIH than in those without the condition. The same pattern was seen for the within-subject analysis. It was observed that the increase in MIH severity resulted in more teeth being affected by dentine carious lesions (p = 0.0003). Children with MIH presented a higher experience of caries in the permanent dentition than those without the condition. MIH was considered a risk factor for caries development. © 2017 S. Karger AG, Basel.

The impact of the Catholic Jubilee in 2000 on infectious diseases. A case-control study of giardiasis, Rome, Italy 2000-2001.

PubMed

Faustini, A; Marinacci, C; Fabrizi, E; Marangi, M; Recchia, O; Pica, R; Giustini, F; La Marca, A; Nacci, A; Panichi, G; Perucci, C A

2006-06-01

Mass gatherings are believed to increase the transmission of infectious diseases although surveillance systems have shown a low impact. The Catholic Jubilee was held in Rome, Italy in 2000. We conducted a case-control study to analyse the risk factors of giardiasis among residents. All diseases reported to the laboratory surveillance system from January 2000 to May 2001 were compared with hospital controls concurrently selected in the same season as cases and frequency-matched for age and birth country. Fifty-two cases (44.1%) and 72 controls were enrolled. In the multivariable analysis factors associated with giardiasis among adults were: travelling abroad (OR 24.2, P>0.01), exposure to surface water (OR 4.80, P=0.05), high educational level (OR 3.8, P=0.03). Having a maid from a high-prevalence country was independently associated (OR 2.3) although not statistically significant. This is the only exposure that changed during the Jubilee.

Risk factors for acute toxoplasmosis in England and Wales.

PubMed

Said, B; Halsby, K D; O'Connor, C M; Francis, J; Hewitt, K; Verlander, N Q; Guy, E; Morgan, D

2017-01-01

Over 300 cases of acute toxoplasmosis are confirmed by reference testing in England and Wales annually. We conducted a case-control study to identify risk factors for Toxoplasma gondii infection to inform prevention strategies. Twenty-eight cases and 27 seronegative controls participated. We compared their food history and environmental exposures using logistic regression to calculate odds ratios (OR) and 95% confidence intervals in a model controlling for age and sex. Univariable analysis showed that the odds of eating beef (OR 10·7, P < 0·001), poultry (OR 6·4, P = 0·01) or lamb/mutton (OR 4·9, P = 0·01) was higher for cases than controls. After adjustment for potential confounders a strong association between beef and infection remained (OR 5·6, P = 0·01). The small sample size was a significant limitation and larger studies are needed to fully investigate potential risk factors. The study findings emphasize the need to ensure food is thoroughly cooked and handled hygienically, especially for those in vulnerable groups.

Polymorphisms of genes coding for ghrelin and its receptor in relation to colorectal cancer risk: a two-step gene-wide case-control study

PubMed Central

2010-01-01

Background Ghrelin, an endogenous ligand for the growth hormone secretagogue receptor (GHSR), has two major functions: the stimulation of the growth hormone production and the stimulation of food intake. Accumulating evidence also indicates a role of ghrelin in cancer development. Methods We conducted a case-control study to examine the association of common genetic variants in the genes coding for ghrelin (GHRL) and its receptor (GHSR) with colorectal cancer risk. Pairwise tagging was used to select the 11 polymorphisms included in the study. The selected polymorphisms were genotyped in 680 cases and 593 controls from the Czech Republic. Results We found two SNPs associated with lower risk of colorectal cancer, namely SNPs rs27647 and rs35683. We replicated the two hits, in additional 569 cases and 726 controls from Germany. Conclusion A joint analysis of the two populations indicated that the T allele of rs27647 SNP exerted a protective borderline effect (Ptrend = 0.004). PMID:20920174

Polymorphisms of genes coding for ghrelin and its receptor in relation to colorectal cancer risk: a two-step gene-wide case-control study.

PubMed

Campa, Daniele; Pardini, Barbara; Naccarati, Alessio; Vodickova, Ludmila; Novotny, Jan; Steinke, Verena; Rahner, Nils; Holinski-Feder, Elke; Morak, Monika; Schackert, Hans K; Görgens, Heike; Kötting, Judith; Betz, Beate; Kloor, Matthias; Engel, Christoph; Büttner, Reinhard; Propping, Peter; Försti, Asta; Hemminki, Kari; Barale, Roberto; Vodicka, Pavel; Canzian, Federico

2010-09-28

Ghrelin, an endogenous ligand for the growth hormone secretagogue receptor (GHSR), has two major functions: the stimulation of the growth hormone production and the stimulation of food intake. Accumulating evidence also indicates a role of ghrelin in cancer development. We conducted a case-control study to examine the association of common genetic variants in the genes coding for ghrelin (GHRL) and its receptor (GHSR) with colorectal cancer risk. Pairwise tagging was used to select the 11 polymorphisms included in the study. The selected polymorphisms were genotyped in 680 cases and 593 controls from the Czech Republic. We found two SNPs associated with lower risk of colorectal cancer, namely SNPs rs27647 and rs35683. We replicated the two hits, in additional 569 cases and 726 controls from Germany. A joint analysis of the two populations indicated that the T allele of rs27647 SNP exerted a protective borderline effect (Ptrend = 0.004).

[Domestic and family violence against women: a case-control study with victims treated in emergency rooms].

PubMed

Garcia, Leila Posenato; Duarte, Elisabeth Carmen; Freitas, Lúcia Rolim Santana de; Silva, Gabriela Drummond Marques da

2016-01-01

This study aimed to identify factors associated with treatment of victims of domestic and family violence in emergency rooms in Brazil. This is a case-control study based on the Surveillance System for Violence and Accidents (VIVA), 2011. Women ≥ 18 years who were victims of family and domestic violence were selected as cases and compared to accident victims (controls). Adjusted odds ratios were estimated by unconditional logistic regression. 623 cases and 10,120 controls were included. Risk factors according to the adjusted analysis were younger age (18-29 years), low schooling, lack of paid work, alcohol consumption, having sought treatment in a different health service, and violence on weekends or at night or in the early morning hours. The study concludes that domestic and family violence shows alcohol consumption as a strongly associated factor. Days and hours with the highest ocurrence reveal the need to adjust emergency services to treat victims.

Role of TNF-α -308G/A gene polymorphism in gastric cancer risk: A case control study and meta-analysis.

PubMed

Du, Li Chuan; Gao, Ru

2017-07-01

In the Chinese population, gastric cancer (GC) is ranked as the third most common type of cancer. Although the exact etiology of GC development is unclear, several factors, including genetic and environmental, have been identified as risk factors. Variations in cytokine genes and their receptors have been related to a higher risk of GC. A single nucleotide polymorphism in the promoter region of tumor necrosis factor-α (TNF-α) (-308G>A) has been associated with a higher risk of GC and in the present study we evaluated its possible association with GC in a Chinese cohort. In addition, we performed a meta-analysis to draw a firm conclusion about the association between TNF-α gene polymorphisms and GC. We enrolled 400 Chinese GC patients and matched healthy controls hailing from similar geographical areas. The TNF-α -308G/A polymorphism was genotyped by allele-specific polymerase chain reaction (AS-PCR). For the meta-analysis, earlier published articles were searched and eligible studies were included. Prevalence of the heterozygous mutant (GA) and minor allele (A) were significantly higher in GC cases compared to healthy controls (GA: p<0.0001, odds ratio (OR)=4.90; A: p<0.0001, OR=2.84). A total of 36 eligible studies including the present report, encompassing of 8353 GC patients and 12099 controls, were analyzed for the meta-analysis. A significant association of the TNF-α polymorphism (-308G>A) with susceptibility to GC was only found in the Caucasian population (A vs G: p=0.001; AA vs GG: p=0.01; AG vs GG: p<0.0001; AA vs AG+GG: p=0.01; AA+AG vs p=0.003). The results of the present case control study and meta-analysis showed that associations between TNF-a variants with susceptibility to GC development is population and ethnic specific.

A Systematic Review and Meta-analysis of the Association Between Giardia lamblia and Endemic Pediatric Diarrhea in Developing Countries

PubMed Central

Muhsen, Khitam; Levine, Myron M.

2012-01-01

We performed a systematic literature review and meta-analysis examining the association between diarrhea in young children in nonindustrialized settings and Giardia lamblia infection. Eligible were case/control and longitudinal studies that defined the outcome as acute or persistent (>14 days) diarrhea, adjusted for confounders and lasting for at least 1 year. Data on G. lamblia detection (mainly in stools) from diarrhea patients and controls without diarrhea were abstracted. Random effects model meta-analysis obtained pooled odds ratios (ORs) and 95% confidence intervals (CIs). Twelve nonindustrialized-setting acute pediatric diarrhea studies met the meta-analysis inclusion criteria. Random-effects model meta-analysis of combined results (9774 acute diarrhea cases and 8766 controls) yielded a pooled OR of 0.60 (95% CI, .38–.94; P = .03), indicating that G. lamblia was not associated with acute diarrhea. However, limited data suggest that initial Giardia infections in early infancy may be positively associated with diarrhea. Meta-analysis of 5 persistent diarrhea studies showed a pooled OR of 3.18 (95% CI, 1.50–6.76; P < .001), positively linking Giardia with that syndrome. The well-powered Global Enteric Multicenter Study (GEMS) is prospectively addressing the association between G. lamblia infection and diarrhea in children in developing countries. PMID:23169940

Financial and clinical characteristics of fibromyalgia: a case-control comparison.

PubMed

Palacio, Ana; Uribe, Claudia L; Li, Hua; Hanna, John; Deminski, Michael; Alvir, Jose; Chandran, Arthi; Sanchez, Robert

2010-05-01

To compare healthcare utilization and costs between subjects with and without fibromyalgia (FM) using claims data from a large health benefits company in the United States. Retrospective cohort. We analyzed 24 months of medical and pharmacy claims data comparing healthcare utilization and costs among Humana members diagnosed with FM to a propensity score matched control group without a diagnosis for FM. FM cases were identified as members aged 18 years and older, with at least 2 medical claims for International Classification of Diseases, Ninth Revision, Clinical Modification codes 729.0 and/or 729.1. The first medical claim for FM was utilized as the index date. A total of 9988 FM cases and 9988 controls were included in the analysis. Compared with controls, the use of pain-related medications by FM cases was approximately 2 times higher with opioids being used most commonly. FM cases utilized a mean (SD) of 22.5 (23.9) and 31.1 (26.6) outpatient services per year in the prediagnosis and postdiagnosis periods, respectively, compared with 14.8 (20.5) and 16.3 (24.5) among controls (P <.01). Office visits, tests, and procedures represented the majority of utilization. During the postdiagnosis period, the mean per-patient per-month costs for outpatient services among FM cases was $377 ($760) and $217 ($740.87) among controls (P <.01). FM cases had significantly higher utilization and costs compared with controls. Office visits, tests and procedures, and the use of pain-related medications accounted for the largest absolute differences between the 2 groups.

Abnormal folate metabolism as a risk factor for first-trimester spontaneous abortion.

PubMed

Hoffman, Michael L; Scoccia, Bert; Kurczynski, Thaddeus W; Shulman, Lee P; Gao, Weihua

2008-03-01

To assess the potential role of folic acid in early pregnancy loss by measuring homocysteine (hcy) levels in healthy, pregnant women who present with a current first-trimester miscarriage. This was a cross-sectional analysis comprising 13 patients aged 18-31 years old who had a scheduled dilatation and curettage for a first-trimester miscarriage. The controls were 15 patients of similar maternal age presenting for a first-trimester prenatal care visit. Following completion of a 21-item, structured questionnaire, patients were excluded from the study if they had any known risk factors for a first-trimester miscarriage. The remaining patients provided blood samples for measurement of homocysteine and red blood cell folate. Cases and controls were compared using a standard 2-sample t test. In order to detect a clinically relevant 2.3 micromol/L difference in homocysteine levels, 11 cases and 8 controls were needed. The mean hcy level in cases (5.8 umolmol/L) vs. controls (5.7 micromol/L) was not significantly different (p = 0.83), and all individual values fell within the normal range expected in pregnant women. Red blood cell folate levels (cases=586 ng/mL, controls=611 ng/mL) were also not significantly different (p = 0.72), and no cases of folate deficiency were detected. Maternal age (cases=26, controls=25) and gestational age (cases = 8.8 weeks, controls = 8.4 weeks) were similar between the 2 groups. In this community-based pilot study, abnormal folate metabolism was not an apparent risk factor for spontaneous first-trimester pregnancy loss.

Genetic Analysis of the Pathogenic Molecular Sub-phenotype Interferon Alpha Identifies Multiple Novel Loci Involved in Systemic Lupus Erythematosus

PubMed Central

Kariuki, Silvia N.; Ghodke-Puranik, Yogita; Dorschner, Jessica M.; Chrabot, Beverly S.; Kelly, Jennifer A.; Tsao, Betty P.; Kimberly, Robert P.; Alarcón-Riquelme, Marta E.; Jacob, Chaim O.; Criswell, Lindsey A.; Sivils, Kathy L.; Langefeld, Carl D.; Harley, John B.; Skol, Andrew D.; Niewold, Timothy B.

2014-01-01

Systemic Lupus Erythematosus (SLE) is a chronic autoimmune disorder characterized by inflammation of multiple organ systems and dysregulated interferon responses. SLE is both genetically and phenotypically heterogeneous, greatly reducing the power of case-control studies in SLE. Elevated circulating interferon alpha (IFN-α) is a stable, heritable trait in SLE, which has been implicated in primary disease pathogenesis. 40–50% of patients have high IFN-α, and high levels correspond with clinical differences. To study genetic heterogeneity in SLE, we performed a case-case study comparing patients with high vs. low IFN-α in over 1550 SLE cases, including GWAS and replication cohorts. In meta-analysis, the top associations in European ancestry were PRKG1 rs7897633 (PMeta=2.75 × 10−8) and PNP rs1049564 (PMeta=1.24 × 10−7). We also found evidence for cross-ancestral background associations with the ANKRD44 and PLEKHF2 loci. These loci have not been previously identified in case-control SLE genetic studies. Bioinformatic analyses implicated these loci functionally in dendritic cells and natural killer cells, both of which are involved in IFN-α production in SLE. As case-control studies of heterogeneous diseases reach a limit of feasibility with respect to subject number and detectable effect size, the study of informative pathogenic subphenotypes becomes an attractive strategy for genetic discovery in complex disease. PMID:25338677

Economic implications of three strategies for the control of taeniasis.

PubMed

Alexander, Anu; John, K R; Jayaraman, T; Oommen, Anna; Venkata Raghava, M; Dorny, Pierre; Rajshekhar, Vedantam

2011-11-01

To evaluate the cost-effectiveness of three strategies for the control of taeniasis in a community, in terms of cost per case treated. A study was conducted in South India to determine the prevalence of taeniasis by screening stool samples from 653 randomly chosen subjects, for coproantigens. The costs incurred in the project were used to estimate the cost per case screened and treated. A one-way sensitivity analysis was carried out for varying rates of taeniasis, different screening strategies and mass therapy. Further sensitivity analysis was carried out with different manpower and test costs. The rate of taeniasis as detected by ELISA for coproantigen was 3 per 1000 (2 of 653 samples). Our study showed that mass therapy without screening for taeniasis would be the most economical strategy in terms of cost per case treated if field workers are employed exclusively for either mass therapy or screening. For each strategy, costs per case treated are higher at low prevalence of taeniasis, with a sharp rise below 15%. In places that are endemic for taeniasis and neurocysticercosis, mass therapy or screening for taeniasis should be considered. Screening by stool microscopy is not cost-effective in terms of cost per case of taeniasis treated owing to its low sensitivity. Although the cost per case of taeniasis treated is high at low prevalence of taeniasis for all options, incorporating mass therapy into existing mass drug distribution programmes might prove to be the most cost-effective control strategy. © 2011 Blackwell Publishing Ltd.

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.

Driving behaviors and on-duty road accidents: a French case-control study.

PubMed

Fort, Emmanuel; Chiron, Mireille; Davezies, Philippe; Bergeret, Alain; Charbotel, Barbara

2013-01-01

A case-control study was carried out to identify driving behaviors associated with the risk of on-duty road accident and to compare driving behaviors according to the type of journey (on duty, commuting, and private) for on-duty road accident victims. Cases were recruited from the Rhône Road Trauma Registry between January 2004 and October 2005 and were on duty at the time of the accident. Control subjects were recruited from the electoral rolls of the case subjects' constituencies of residence. Cases' and controls' driving behavior data were collected by self-administered questionnaire. A logistic regression was performed to identify behavioral risk factors for on-duty road accidents, taking into account age, sex, place of residence, road accident risk exposure, socio-occupational category, and type of road user. A second analysis focused specifically on the case subjects, comparing their self-assessed usual behaviors according to the type of journey. Significant factors for multivariate analysis of on-duty road accidents were female gender, history of on-duty road accidents during the previous 10 years, severe time pressure at work, and driving a vehicle not belonging to the driver. On-duty road accident victims reported behavioral risk factors more frequently in relation to driving for work than driving for private reasons or commuting: nonsystematic seat belt use, cell phone use at least once daily while driving, and history of accidents with injury during the previous 10 years. This study provides knowledge on behavioral risk factors for on-duty road accidents and differences in behavior according to the type of journey for subjects who have been on-duty road accident victims. These results will be useful for the design of on-duty road risk prevention.

The effect of vaccination coverage and climate on Japanese encephalitis in Sarawak, Malaysia.

PubMed

Impoinvil, Daniel E; Ooi, Mong How; Diggle, Peter J; Caminade, Cyril; Cardosa, Mary Jane; Morse, Andrew P; Baylis, Matthew; Solomon, Tom

2013-01-01

Japanese encephalitis (JE) is the leading cause of viral encephalitis across Asia with approximately 70,000 cases a year and 10,000 to 15,000 deaths. Because JE incidence varies widely over time, partly due to inter-annual climate variability effects on mosquito vector abundance, it becomes more complex to assess the effects of a vaccination programme since more or less climatically favourable years could also contribute to a change in incidence post-vaccination. Therefore, the objective of this study was to quantify vaccination effect on confirmed Japanese encephalitis (JE) cases in Sarawak, Malaysia after controlling for climate variability to better understand temporal dynamics of JE virus transmission and control. Monthly data on serologically confirmed JE cases were acquired from Sibu Hospital in Sarawak from 1997 to 2006. JE vaccine coverage (non-vaccine years vs. vaccine years) and meteorological predictor variables, including temperature, rainfall and the Southern Oscillation index (SOI) were tested for their association with JE cases using Poisson time series analysis and controlling for seasonality and long-term trend. Over the 10-years surveillance period, 133 confirmed JE cases were identified. There was an estimated 61% reduction in JE risk after the introduction of vaccination, when no account is taken of the effects of climate. This reduction is only approximately 45% when the effects of inter-annual variability in climate are controlled for in the model. The Poisson model indicated that rainfall (lag 1-month), minimum temperature (lag 6-months) and SOI (lag 6-months) were positively associated with JE cases. This study provides the first improved estimate of JE reduction through vaccination by taking account of climate inter-annual variability. Our analysis confirms that vaccination has substantially reduced JE risk in Sarawak but this benefit may be overestimated if climate effects are ignored.

Pooled analysis of two case-control studies on the use of cellular and cordless telephones and the risk of benign brain tumours diagnosed during 1997-2003.

PubMed

Hardell, Lennart; Carlberg, Michael; Hansson Mild, Kjell

2006-02-01

The use of cellular and cordless telephones and the risk of brain tumours is of concern since the brain is a high exposure area. We present the results of a pooled analysis of two case-control studies on benign brain tumours diagnosed during 1997-2003 including answers from 1,254 (88%) cases and 2,162 (89%) controls aged 20-80 years. For acoustic neuroma, the use of analogue cellular phones gave an odds ratio (OR) of 2.9 and a 95% confidence interval (CI) of 2.0-4.3; for digital cellular phones, OR=1.5; 95% CI=1.1-2.1; and for cordless telephones, OR=1.5, 95% CI=1.04-2.0. The highest OR was found for analogue phones with a latency period of >15 years; OR=3.8, 95% CI=1.4-10. Regarding meningioma, the results were as follows: for analogue phones, OR=1.3, 95% CI=0.99-1.7; for digital phones, OR=1.1, 95% CI=0.9-1.3; and for cordless phones, OR=1.1, 95% CI=0.9-1.4. In the multivariate analysis, a significantly increased risk of acoustic neuroma was found with the use of analogue phones.

Association of β-defensin copy number and psoriasis in three cohorts of European origin

PubMed Central

Stuart, Philip E; Hüffmeier, Ulrike; Nair, Rajan P; Palla, Raquel; Tejasvi, Trilokraj; Schalkwijk, Joost; Elder, James T; Reis, Andre; Armour, John AL

2012-01-01

A single previous study has demonstrated significant association of psoriasis with copy number of beta-defensin genes, using DNA from psoriasis cases and controls from Nijmegen and Erlangen. In this study we attempted to replicate that finding in larger new cohorts from Erlangen (N = 2017) and Michigan (N = 5412), using improved methods for beta-defensin copy number determination based on the paralog ratio test (PRT), and enhanced methods of analysis and association testing implemented in the CNVtools resource. We demonstrate that the association with psoriasis found in the discovery sample is maintained after applying improved typing and analysis methods (p = 5.5 × 10−4, OR = 1.25). We also find that the association is replicated in 2616 cases and 2526 controls from Michigan, although at reduced significance (p = 0.014), but not in new samples from Erlangen (1396 cases and 621 controls, p = 0.38). Meta-analysis across all cohorts suggests a nominally significant association (p = 6.6 × 10−3/2 × 10−4) with an effect size (OR = 1.081) much lower than found in the discovery study (OR = 1.32). This reduced effect size and significance on replication is consistent with a genuine but weak association. PMID:22739795

Factors that are associated with the risk of acquiring Plasmodium knowlesi malaria in Sabah, Malaysia: a case-control study protocol

PubMed Central

Grigg, M J; William, T; Drakeley, C J; Jelip, J; von Seidlein, L; Barber, B E; Fornace, K M; Anstey, N M; Yeo, T W; Cox, J

2014-01-01

Introduction Plasmodium knowlesi has long been present in Malaysia, and is now an emerging cause of zoonotic human malaria. Cases have been confirmed throughout South-East Asia where the ranges of its natural macaque hosts and Anopheles leucosphyrus group vectors overlap. The majority of cases are from Eastern Malaysia, with increasing total public health notifications despite a concurrent reduction in Plasmodium falciparum and P. vivax malaria. The public health implications are concerning given P. knowlesi has the highest risk of severe and fatal disease of all Plasmodium spp in Malaysia. Current patterns of risk and disease vary based on vector type and competence, with individual exposure risks related to forest and forest-edge activities still poorly defined. Clustering of cases has not yet been systematically evaluated despite reports of peri-domestic transmission and known vector competence for human-to-human transmission. Methods and analysis A population-based case–control study will be conducted over a 2-year period at two adjacent districts in north-west Sabah, Malaysia. Confirmed malaria cases presenting to the district hospital sites meeting relevant inclusion criteria will be requested to enrol. Three community controls matched to the same village as the case will be selected randomly. Study procedures will include blood sampling and administration of household and individual questionnaires to evaluate potential exposure risks associated with acquisition of P. knowlesi malaria. Secondary outcomes will include differences in exposure variables between P. knowlesi and other Plasmodium spp, risk of severe P. knowlesi malaria, and evaluation of P. knowlesi case clustering. Primary analysis will be per protocol, with adjusted ORs for exposure risks between cases and controls calculated using conditional multiple logistic regression models. Ethics This study has been approved by the human research ethics committees of Malaysia, the Menzies School of Health Research, Australia, and the London School of Hygiene and Tropical Medicine, UK. PMID:25149186

An Analysis of Internal Controls for DoD Contract Management

DTIC Science & Technology

2015-12-01

61 xiv THIS PAGE INTENTIONALLY LEFT BLANK xv LIST OF ACRONYMS AND ABBREVIATIONS BCA Business Case Analysis BPA ...indefinite quantity (IDIQ) and blanket purchase agreements ( BPA ), which can provide the government flexibility on ordering recurring requirements. Figure 5

Lack of association between migraine headache and patent foramen ovale: results of a case-control study.

PubMed

Garg, Pallav; Servoss, Stephen J; Wu, Justina C; Bajwa, Zahid H; Selim, Magdy H; Dineen, Alexis; Kuntz, Richard E; Cook, E Francis; Mauri, Laura

2010-03-30

Clinical observations of migraine headache symptoms in patients with a patent foramen ovale (PFO), both of which conditions are highly prevalent, have raised the question of a possible pathophysiological relationship. We sought to evaluate the assumption of an association between migraine headaches and the presence of PFO by use of a large case-control study. We conducted a case-control study to assess the prevalence of PFO in subjects with and without migraine. Case subjects were those with a history of migraine (diagnosed by neurologists at a specialty academic headache clinic). Control subjects were healthy volunteers without migraine 1:1 matched on the basis of age and sex with case subjects. Presence of PFO was determined by transthoracic echocardiogram with second harmonic imaging and transcranial Doppler ultrasonography during a standardized procedure of infused agitated saline contrast with or without Valsalva maneuver and a review of the results by experts blinded to case-control status. PFO was considered present if both studies were positive. Odds ratios were calculated with conditional logistic regression in the matched cohort (n=288). In the matched analysis, the prevalence of PFO was similar in case and control subjects (26.4% versus 25.7%; odds ratio 1.04, 95% confidence interval 0.62 to 1.74, P=0.90). There was no difference in PFO prevalence in those with migraine with aura and those without (26.8% versus 26.1%; odds ratio 1.03, 95% confidence interval 0.48 to 2.21, P=0.93). We found no association between migraine headaches and the presence of PFO in this large case-control study.

Continuous Positive Airway Pressure Adherence In Patients with Obstructive Sleep Apnea & Symptomatic BPH.

PubMed

Metta, Ramesh V V S; Zaka, Awais; Lee, Vincent C; Mador, M Jeffery

2017-04-01

Purpose To determine the short-term and long-term adherence rates with continuous positive airway pressure (CPAP) therapy in sleep apnea patients with benign prostatic hyperplasia (BPH) compared to matched controls. Methods A case-control retrospective analysis was performed in a veterans affairs hospital. All symptomatic patients with BPH (n = 107) ever started on CPAP therapy between 2006 and 2012 were compared with controls matched for severity of sleep apnea (AHI). Adherence measures were obtained at the third and twelfth month visits. The cases included symptomatic BPH patients on active medical therapy. Diuretic use among cases and controls, and severity of nocturia among the cases were also analyzed. Results The mean AHI among cases and controls was 35.6 ± 27.3 and 35.5 ± 31 (p = 0.96). The population was male and predominantly Caucasian. There was no statistically significant difference in percent days CPAP device use ≥4 h. between symptomatic BPH patients and controls at 3-month (51.6 ± 38 vs. 47.2 ± 36; p = 0.43) and 1-year (64 ± 40.5 vs. 64.7 ± 31.3; p = 0.90) visits. The use of diuretics in the cases and controls, and the severity of nocturia in the cases did not influence adherence with CPAP therapy. Conclusions BPH or diuretic use did not affect adherence with CPAP therapy in obstructive sleep apnea. Severity of nocturia did not have any influence on adherence among the cases. BPH, regardless of the severity of nocturia, and diuretic use does not influence CPAP adherence in patients with OSA.

Meta-analysis of erythrocyte polyunsaturated fatty acid biostatus in bipolar disorder.

PubMed

McNamara, Robert K; Welge, Jeffrey A

2016-05-01

Dietary deficiency in polyunsaturated fatty acids (PUFAs), including the omega-3 fatty acids eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3), and excesses in omega-6 fatty acids, including linoleic acid (LA; 18:2n-6) and arachidonic acid (AA; 20:4n-6), may be associated with the pathophysiology of bipolar disorder. In an effort to provide clarification regarding the relationship between PUFA biostatus and bipolar disorder, this meta-analysis investigated studies comparing erythrocyte (red blood cell) membrane PUFA composition in patients with bipolar disorder and healthy controls. A meta-analysis was performed on case-control studies comparing erythrocyte PUFA (EPA, DHA, LA and AA) levels in patients with bipolar I disorder and healthy controls. Standardized effect sizes were calculated and combined using a random effects model. Six eligible case-control studies comprising n = 118 bipolar I patients and n = 147 healthy controls were included in the analysis. Compared with healthy controls, patients with bipolar I disorder exhibited robust erythrocyte DHA deficits (p = 0.0008) and there was a trend for lower EPA (p = 0.086). There were no significant differences in LA (p = 0.42) or AA (p = 0.64). Bipolar I disorder is associated with robust erythrocyte DHA deficits. These findings add to a growing body of evidence implicating omega-3 PUFA deficiency in the pathophysiology of bipolar disorder. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Elevated serum levels of ghrelin and TNF-α in patients with cyanotic and acyanotic congenital heart disease.

PubMed

Zhang, Sai; Guo, Gong-Liang; Yang, Li-Li; Sun, Li-Qun

2017-04-01

The levels of ghrelin and tumor necrosis factor alpha (TNF-α) are considered biological markers of congenital heart diseases (CHD). The present meta-analysis was conducted to investigate the clinical significance of serum levels of ghrelin and TNF-α in children with (CHD). Chinese and English scientific literature databases were searched to retrieve published studies relevant to ghrelin, TNF-α and CHD. Manual search was additionally employed to identify other relevant studies from cross-references. The retrieved studies were screened on the basis of our stringent inclusion and exclusion criteria to select high quality case-control studies for meta-analysis. We initially retrieved 108 published studies (20 in Chinese and 88 in English) from database searches. Finally, 6 case-control studies (5 in English and 1 in Chinese) were enrolled in our meta-analysis, and contained a total of 160 cyanotic congenital heart disease (CCHD) patients and 215 acyanotic congenital heart disease (ACHD) patients, along with 162 healthy controls. The results of meta-analysis showed that serum levels of ghrelin and TNF-α in CCHD or ACHD children were significantly higher than those in healthy controls. Our meta-analysis results showed that serum levels of ghrelin and TNF-α are elevated in children with CHD, and could be used as effective biologic markers in early diagnosis of CHD.

Dietary patterns, goitrogenic food, and thyroid cancer: a case-control study in French Polynesia.

PubMed

Cléro, Énora; Doyon, Françoise; Chungue, Vaïana; Rachédi, Frédérique; Boissin, Jean-Louis; Sebbag, Joseph; Shan, Larrys; Rubino, Carole; de Vathaire, Florent

2012-01-01

French Polynesia has one of the world's highest thyroid cancer incidence rates. A case-control study among native residents of French Polynesia included 229 cases of differentiated thyroid cancer diagnosed between 1979 and 2004, and 371 population controls. Dietary patterns and goitrogenic food consumption (cabbage, cassava) were analyzed. We used a factor analysis to identify dietary patterns and a conditional logistic regression analysis to investigate the association between dietary patterns or food items and thyroid cancer risk. Two distinct dietary patterns were identified: traditional Polynesian and Western. A nonsignificant inverse association was observed between the traditional Polynesian dietary pattern and thyroid cancer risk. The Western pattern was not associated with thyroid cancer risk. Cassava consumption was significantly associated with a decreased risk of thyroid cancer. In conclusion, a traditional Polynesian dietary pattern led to a weak reduced risk of thyroid cancer in French Polynesia. The protective effect of cassava on this cancer does not seem to be substantially different from that of cabbage, which was the main goitrogenic food studied to date.

Genome-wide association analysis identifies 13 new risk loci for schizophrenia.

PubMed

Ripke, Stephan; O'Dushlaine, Colm; Chambert, Kimberly; Moran, Jennifer L; Kähler, Anna K; Akterin, Susanne; Bergen, Sarah E; Collins, Ann L; Crowley, James J; Fromer, Menachem; Kim, Yunjung; Lee, Sang Hong; Magnusson, Patrik K E; Sanchez, Nick; Stahl, Eli A; Williams, Stephanie; Wray, Naomi R; Xia, Kai; Bettella, Francesco; Borglum, Anders D; Bulik-Sullivan, Brendan K; Cormican, Paul; Craddock, Nick; de Leeuw, Christiaan; Durmishi, Naser; Gill, Michael; Golimbet, Vera; Hamshere, Marian L; Holmans, Peter; Hougaard, David M; Kendler, Kenneth S; Lin, Kuang; Morris, Derek W; Mors, Ole; Mortensen, Preben B; Neale, Benjamin M; O'Neill, Francis A; Owen, Michael J; Milovancevic, Milica Pejovic; Posthuma, Danielle; Powell, John; Richards, Alexander L; Riley, Brien P; Ruderfer, Douglas; Rujescu, Dan; Sigurdsson, Engilbert; Silagadze, Teimuraz; Smit, August B; Stefansson, Hreinn; Steinberg, Stacy; Suvisaari, Jaana; Tosato, Sarah; Verhage, Matthijs; Walters, James T; Levinson, Douglas F; Gejman, Pablo V; Kendler, Kenneth S; Laurent, Claudine; Mowry, Bryan J; O'Donovan, Michael C; Owen, Michael J; Pulver, Ann E; Riley, Brien P; Schwab, Sibylle G; Wildenauer, Dieter B; Dudbridge, Frank; Holmans, Peter; Shi, Jianxin; Albus, Margot; Alexander, Madeline; Campion, Dominique; Cohen, David; Dikeos, Dimitris; Duan, Jubao; Eichhammer, Peter; Godard, Stephanie; Hansen, Mark; Lerer, F Bernard; Liang, Kung-Yee; Maier, Wolfgang; Mallet, Jacques; Nertney, Deborah A; Nestadt, Gerald; Norton, Nadine; O'Neill, Francis A; Papadimitriou, George N; Ribble, Robert; Sanders, Alan R; Silverman, Jeremy M; Walsh, Dermot; Williams, Nigel M; Wormley, Brandon; Arranz, Maria J; Bakker, Steven; Bender, Stephan; Bramon, Elvira; Collier, David; Crespo-Facorro, Benedicto; Hall, Jeremy; Iyegbe, Conrad; Jablensky, Assen; Kahn, Rene S; Kalaydjieva, Luba; Lawrie, Stephen; Lewis, Cathryn M; Lin, Kuang; Linszen, Don H; Mata, Ignacio; McIntosh, Andrew; Murray, Robin M; Ophoff, Roel A; Powell, John; Rujescu, Dan; Van Os, Jim; Walshe, Muriel; Weisbrod, Matthias; Wiersma, Durk; Donnelly, Peter; Barroso, Ines; Blackwell, Jenefer M; Bramon, Elvira; Brown, Matthew A; Casas, Juan P; Corvin, Aiden P; Deloukas, Panos; Duncanson, Audrey; Jankowski, Janusz; Markus, Hugh S; Mathew, Christopher G; Palmer, Colin N A; Plomin, Robert; Rautanen, Anna; Sawcer, Stephen J; Trembath, Richard C; Viswanathan, Ananth C; Wood, Nicholas W; Spencer, Chris C A; Band, Gavin; Bellenguez, Céline; Freeman, Colin; Hellenthal, Garrett; Giannoulatou, Eleni; Pirinen, Matti; Pearson, Richard D; Strange, Amy; Su, Zhan; Vukcevic, Damjan; Donnelly, Peter; Langford, Cordelia; Hunt, Sarah E; Edkins, Sarah; Gwilliam, Rhian; Blackburn, Hannah; Bumpstead, Suzannah J; Dronov, Serge; Gillman, Matthew; Gray, Emma; Hammond, Naomi; Jayakumar, Alagurevathi; McCann, Owen T; Liddle, Jennifer; Potter, Simon C; Ravindrarajah, Radhi; Ricketts, Michelle; Tashakkori-Ghanbaria, Avazeh; Waller, Matthew J; Weston, Paul; Widaa, Sara; Whittaker, Pamela; Barroso, Ines; Deloukas, Panos; Mathew, Christopher G; Blackwell, Jenefer M; Brown, Matthew A; Corvin, Aiden P; McCarthy, Mark I; Spencer, Chris C A; Bramon, Elvira; Corvin, Aiden P; O'Donovan, Michael C; Stefansson, Kari; Scolnick, Edward; Purcell, Shaun; McCarroll, Steven A; Sklar, Pamela; Hultman, Christina M; Sullivan, Patrick F

2013-10-01

Schizophrenia is an idiopathic mental disorder with a heritable component and a substantial public health impact. We conducted a multi-stage genome-wide association study (GWAS) for schizophrenia beginning with a Swedish national sample (5,001 cases and 6,243 controls) followed by meta-analysis with previous schizophrenia GWAS (8,832 cases and 12,067 controls) and finally by replication of SNPs in 168 genomic regions in independent samples (7,413 cases, 19,762 controls and 581 parent-offspring trios). We identified 22 loci associated at genome-wide significance; 13 of these are new, and 1 was previously implicated in bipolar disorder. Examination of candidate genes at these loci suggests the involvement of neuronal calcium signaling. We estimate that 8,300 independent, mostly common SNPs (95% credible interval of 6,300-10,200 SNPs) contribute to risk for schizophrenia and that these collectively account for at least 32% of the variance in liability. Common genetic variation has an important role in the etiology of schizophrenia, and larger studies will allow more detailed understanding of this disorder.

Interleukin-10-1082G/A polymorphism and acute liver graft rejection: A meta-analysis

PubMed Central

Liu, Fei; Li, Bo; Wang, Wen-Tao; Wei, Yong-Gang; Yan, Lv-Nan; Wen, Tian-Fu; Xu, Ming-Qing; Yang, Jia-Yin

2012-01-01

AIM: To investigate the association between interleukin (IL)-10-1082 (G/A) promoter polymorphism and acute rejection (AR) in liver transplant (LT) recipients. METHODS: Two investigators independently searched the Medline, Embase, China National Knowledge Infrastructure, and Chinese Biomedicine Databases. Summary odds ratios (ORs) and 95% CIs for IL-10-1082 G/A polymorphism and AR were calculated in a fixed- and a random-effects model as appropriate. RESULTS: This meta-analysis included seven case-control studies, which comprised 652 cases of LT recipients in which 241 cases developed AR and 411 cases did not develop AR. Overall, the variant A allele was not associated with AR risk when compared with the wild-type G allele (OR = 0.94, 95% CI: 0.64-1.39). Moreover, similar results were observed when the AA genotype was compared with the AG/GG genotype (OR = 1.05, 95% CI: 0.55-2.02). When stratifying for ethnicity, no significant association was observed among either Caucasians or Asians. Because only one study was performed in Asian patients, the result of subgroup analysis by ethnicity would not be reliable for Asians. Limiting the analysis to the studies with controls in the Hardy-Weinberg equilibrium, the results were persistent and robust. No publication bias was found in the present study. CONCLUSION: This meta-analysis suggests that IL-10-1082 G/A polymorphism may be not associated with AR risk in LT recipients among Caucasians. PMID:22371646

Tramadol use and the risk of hospitalization for hypoglycemia in patients with noncancer pain.

PubMed

Fournier, Jean-Pascal; Azoulay, Laurent; Yin, Hui; Montastruc, Jean-Louis; Suissa, Samy

2015-02-01

Tramadol is a weak opioid analgesic whose use has increased rapidly, and it has been associated with adverse events of hypoglycemia. To assess whether tramadol use, when compared with codeine use, is associated with an increased risk of hospitalization for hypoglycemia. A nested case-control analysis was conducted within the United Kingdom Clinical Practice Research Datalink linked to the Hospital Episodes Statistics database of all patients newly treated with tramadol or codeine for noncancer pain between 1998 and 2012. Cohort and case-crossover analyses were also conducted to assess consistency of the results. Cases of hospitalization for hypoglycemia were matched with up to 10 controls on age, sex, and duration of follow-up. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated comparing use of tramadol with codeine. A cohort analysis, with high-dimensional propensity score-adjusted hazard ratios (HRs) and 95% CIs, was performed comparing tramadol with codeine in the first 30 days after treatment initiation. Finally, a case-crossover analysis was also performed, in which exposure to tramadol in a 30-day risk period immediately before the hospitalization for hypoglycemia was compared with 11 consecutive 30-day control periods. Odds ratios and 95% CIs were estimated using conditional logistic regression analysis. The cohort included 334,034 patients, of whom 1105 were hospitalized for hypoglycemia during follow-up (incidence, 0.7 per 1000 per year) and matched to 11,019 controls. Compared with codeine, tramadol use was associated with an increased risk of hospitalization for hypoglycemia (OR, 1.52 [95% CI, 1.09-2.10]), particularly elevated in the first 30 days of use (OR, 2.61 [95% CI, 1.61-4.23]). This 30-day increased risk was confirmed in the cohort (HR, 3.60 [95% CI, 1.56-8.34]) and case-crossover analyses (OR, 3.80 [95% CI, 2.64-5.47]). The initiation of tramadol therapy is associated with an increased risk of hypoglycemia requiring hospitalization. Additional studies are needed to confirm this rare but potentially fatal adverse event.

Statin use is associated with reduced risk of histologic subtypes of esophageal cancer: a nested case-control analysis.

PubMed

Alexandre, Leo; Clark, Allan B; Bhutta, Hina Y; Holt, Sean; Lewis, Michael P N; Hart, Andrew R

2014-03-01

Most patients with esophageal adenocarcinoma (EAC) or squamous cell cancer (ESCC) present with advanced, incurable disease. Statins have reported anti-carcinogenic effects and may be chemoprotective. We investigated the association between regular use of statins and the main histologic subtypes of esophageal malignancy (EAC, esophagogastric junctional adenocarcinoma, and ESCC) in the UK general population. We identified all individuals in the UK General Practice Research Database diagnosed with esophageal cancer from 2000 through 2009. Patients were linked to the National Cancer Registry to confirm histologic subtypes. Each patient was matched with up to 4 controls for age, sex, and practice. We performed a nested case-control analysis using conditional logistic regression to estimate the risk of each subtype with regular statin use, adjusted for body mass index, smoking, alcohol intake, and concomitant use of medications. In total, 581 participants with EAC, 213 with esophagogastric junctional adenocarcinoma, and 332 with ESCC were matched to 2167, 783, and 1242 controls, respectively. Regular statin use was inversely associated with development of EAC (odds ratio = 0.58; 95% confidence interval: 0.39-0.87) (with significant dose and duration responses) and esophagogastric junctional adenocarcinoma (odds ratio = 0.29; 95% confidence interval: 0.09-0.92) (with high-dose use only). Statin use for 1-4 years was inversely associated with ESCC (odds ratio = 0.51; 95% confidence interval: 0.27-0.98). In a nested case-control analysis of a UK population-based cohort, statin use was inversely associated with histologic subtypes of esophageal cancer. Randomized controlled trials are warranted to determine whether statins have chemopreventive effects in high-risk groups. Copyright © 2014 AGA Institute. Published by Elsevier Inc. All rights reserved.

Mean Platelet Volume (MPV), Platelet Distribution Width (PDW), Platelet Count and Plateletcrit (PCT) as predictors of in-hospital paediatric mortality: a case-control Study.

PubMed

Golwala, Zainab Mohammedi; Shah, Hardik; Gupta, Neeraj; Sreenivas, V; Puliyel, Jacob M

2016-06-01

Thrombocytopenia has been shown to predict mortality. We hypothesize that platelet indices may be more useful prognostic indicators. Our study subjects were children one month to 14 years old admitted to our hospital. To determine whether platelet count, plateletcrit (PCT), mean platelet volume (MPV) and platelet distribution width (PDW) and their ratios can predict mortality in hospitalised children. Children who died during hospital stay were the cases. Controls were age matched children admitted contemporaneously. The first blood sample after admission was used for analysis. Receiver operating characteristic (ROC) curve was used to identify the best threshold for measured variables and the ratios studied. Multiple regression analysis was done to identify independent predictors of mortality. Forty cases and forty controls were studied. Platelet count, PCT and the ratios of MPV/Platelet count, MPV/PCT, PDW/Platelet count, PDW/PCT and MPV × PDW/Platelet count × PCT were significantly different among children who survived compared to those who died. On multiple regression analysis the ratio of MPV/PCT, PDW/Platelet count and MPV/Platelet count were risk factors for mortality with an odds ratio of 4.31(95% CI, 1.69-10.99), 3.86 (95% CI, 1.53-9.75), 3.45 (95% CI, 1.38-8.64) respectively. In 67% of the patients who died MPV/PCT ratio was above 41.8 and PDW/Platelet count was above 3.86. In 65% of patients who died MPV/Platelet count was above 3.45. The MPV/PCT, PDW/Platelet count and MPV/Platelet count, in the first sample after admission in this case control study were predictors of mortality and could predict 65% to 67% of deaths accurately.

Pooled analysis of Swedish case-control studies during 1997-2003 and 2007-2009 on meningioma risk associated with the use of mobile and cordless phones.

PubMed

Carlberg, Michael; Hardell, Lennart

2015-06-01

A pooled analysis of two case-control studies on meningioma with patients diagnosed during 1997-2003 and 2007-2009 was conducted. Both genders were included, aged 20-80 and 18-75 years, respectively, at the time of diagnosis. Population-based controls, matched according to age and gender, were enrolled. Exposure was assessed by questionnaire. In the entire study, cases with all brain tumor types were included. The whole reference group was used in the unconditional logistic regression analysis on meningioma, with adjustments for gender, age, year of diagnosis and socio-economic index (SEI). In total, 1,625 meningioma cases and 3,530 controls were analyzed. Overall no association with use of mobile or cordless phones was found. In the fourth quartile of use (>1,436 h) somewhat increased risk was found for mobile phones yielding an odds ratio (OR)=1.2, 95% confidence intervals (CI)=0.9-1.6 and cordless phones OR=1.7, 95% CI=1.3-2.2. Higher risk was calculated in the highest decile (>3,358 h), OR=1.5, 95% CI=0.99-2.1 and OR=2.0, 95% CI=1.4-2.8, respectively. In addition, the longest latency time gave somewhat increased risk for both phone types although the result was not statistically significant. There was no association for ipsilateral use or anatomical tumor location. The present study showed a somewhat increased risk among heavy users of mobile and cordless phones. Since meningioma is generally a slow-growing tumor, longer latency period is necessary for definitive conclusions.

Association of Interleukin-1 gene clusters polymorphisms with primary open-angle glaucoma: a meta-analysis.

PubMed

Li, Junhua; Feng, Yifan; Sung, Mi Sun; Lee, Tae Hee; Park, Sang Woo

2017-11-28

Previous studies have associated the Interleukin-1 (IL-1) gene clusters polymorphisms with the risk of primary open-angle glaucoma (POAG). However, the results were not consistent. Here, we performed a meta-analysis to evaluate the role of IL-1 gene clusters polymorphisms in POAG susceptibility. PubMed, EMBASE and Cochrane Library (up to July 15, 2017) were searched by two independent investigators. All case-control studies investigating the association between single-nucleotide polymorphisms (SNPs) of IL-1 gene clusters and POAG risk were included. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated for quantifying the strength of association that has been involved in at least two studies. Five studies on IL-1β rs16944 (c. -511C > T) (1053 cases and 986 controls), 4 studies on IL-1α rs1800587 (c. -889C > T) (822 cases and 714 controls), and 4 studies on IL-1β rs1143634 (c. +3953C > T) (798 cases and 730 controls) were included. The results suggest that all three SNPs were not associated with POAG risk. Stratification analyses indicated that the rs1143634 has a suggestive associated with high tension glaucoma (HTG) under dominant (P = 0.03), heterozygote (P = 0.04) and allelic models (P = 0.02), however, the weak association was nullified after Bonferroni adjustments for multiple tests. Based on current meta-analysis, we indicated that there is lack of association between the three SNPs of IL-1 and POAG. However, this conclusion should be interpreted with caution and further well designed studies with large sample-size are required to validate the conclusion as low statistical powers.

Partial AZFc duplications not deletions are associated with male infertility in the Yi population of Yunnan Province, China.

PubMed

Ye, Jun-jie; Ma, Li; Yang, Li-juan; Wang, Jin-huan; Wang, Yue-li; Guo, Hai; Gong, Ning; Nie, Wen-hui; Zhao, Shu-hua

2013-09-01

There are many reports on associations between spermatogenesis and partial azoospermia factor c (AZFc) deletions as well as duplications; however, results are conflicting, possibly due to differences in methodology and ethnic background. The purpose of this study is to investigate the association of AZFc polymorphisms and male infertility in the Yi ethnic population, residents within Yunnan Province, China. A total of 224 infertile patients and 153 fertile subjects were selected in the Yi ethnic population. The study was performed by sequence-tagged site plus/minus (STS+/-) analysis followed by gene dosage and gene copy definition analysis. Y haplotypes of 215 cases and 115 controls were defined by 12 binary markers using single nucleotide polymorphism on Y chromosome (Y-SNP) multiplex assays based on single base primer extension technology. The distribution of Y haplotypes was not significantly different between the case and control groups. The frequencies of both gr/gr (7.6% vs. 8.5%) and b2/b3 (6.3% vs. 8.5%) deletions do not show significant differences. Similarly, single nucleotide variant (SNV) analysis shows no significant difference of gene copy definition between the cases and controls. However, the frequency of partial duplications in the infertile group (4.0%) is significantly higher than that in the control group (0.7%). Further, we found a case with sY1206 deletion which had two CDY1 copies but removed half of DAZ genes. Our results show that male infertility is associated with partial AZFc duplications, but neither gr/gr nor b2/b3 deletions, suggesting that partial AZFc duplications rather than deletions are risk factors for male infertility in Chinese-Yi population.

Genetic variation in the ADIPOQ gene, adiponectin concentrations and risk of colorectal cancer: a Mendelian Randomization analysis using data from three large cohort studies.

PubMed

Nimptsch, Katharina; Song, Mingyang; Aleksandrova, Krasimira; Katsoulis, Michail; Freisling, Heinz; Jenab, Mazda; Gunter, Marc J; Tsilidis, Konstantinos K; Weiderpass, Elisabete; Bueno-De-Mesquita, H Bas; Chong, Dawn Q; Jensen, Majken K; Wu, Chunsen; Overvad, Kim; Kühn, Tilman; Barrdahl, Myrto; Melander, Olle; Jirström, Karin; Peeters, Petra H; Sieri, Sabina; Panico, Salvatore; Cross, Amanda J; Riboli, Elio; Van Guelpen, Bethany; Myte, Robin; Huerta, José María; Rodriguez-Barranco, Miguel; Quirós, José Ramón; Dorronsoro, Miren; Tjønneland, Anne; Olsen, Anja; Travis, Ruth; Boutron-Ruault, Marie-Christine; Carbonnel, Franck; Severi, Gianluca; Bonet, Catalina; Palli, Domenico; Janke, Jürgen; Lee, Young-Ae; Boeing, Heiner; Giovannucci, Edward L; Ogino, Shuji; Fuchs, Charles S; Rimm, Eric; Wu, Kana; Chan, Andrew T; Pischon, Tobias

2017-05-01

Higher levels of circulating adiponectin have been related to lower risk of colorectal cancer in several prospective cohort studies, but it remains unclear whether this association may be causal. We aimed to improve causal inference in a Mendelian Randomization meta-analysis using nested case-control studies of the European Prospective Investigation into Cancer and Nutrition (EPIC, 623 cases, 623 matched controls), the Health Professionals Follow-up Study (HPFS, 231 cases, 230 controls) and the Nurses' Health Study (NHS, 399 cases, 774 controls) with available data on pre-diagnostic adiponectin concentrations and selected single nucleotide polymorphisms in the ADIPOQ gene. We created an ADIPOQ allele score that explained approximately 3% of the interindividual variation in adiponectin concentrations. The ADIPOQ allele score was not associated with risk of colorectal cancer in logistic regression analyses (pooled OR per score-unit unit 0.97, 95% CI 0.91, 1.04). Genetically determined twofold higher adiponectin was not significantly associated with risk of colorectal cancer using the ADIPOQ allele score as instrumental variable (pooled OR 0.73, 95% CI 0.40, 1.34). In a summary instrumental variable analysis (based on previously published data) with higher statistical power, no association between genetically determined twofold higher adiponectin and risk of colorectal cancer was observed (0.99, 95% CI 0.93, 1.06 in women and 0.94, 95% CI 0.88, 1.01 in men). Thus, our study does not support a causal effect of circulating adiponectin on colorectal cancer risk. Due to the limited genetic determination of adiponectin, larger Mendelian Randomization studies are necessary to clarify whether adiponectin is causally related to lower risk of colorectal cancer.

Use of acid-suppressive drugs and risk of fracture: a meta-analysis of observational studies.

PubMed

Eom, Chun-Sick; Park, Sang Min; Myung, Seung-Kwon; Yun, Jae Moon; Ahn, Jeong-Soo

2011-01-01

Previous studies have reported inconsistent findings regarding the association between the use of acid-suppressive drugs such as proton pump inhibitors (PPIs) and histamine 2 receptor antagonists (H(2)RAs) and fracture risk. We investigated this association using meta-analysis. We searched MEDLINE (PubMed), EMBASE, and the Cochrane Library from inception through December 2010 using common key words. We included case-control, nested case-control, and cohort studies. Two evaluators independently reviewed and selected articles. We determined pooled effect estimates by using random-effects meta-analysis, because of heterogeneity. Of 1,809 articles meeting our initial inclusion criteria, 5 case-control studies, 3 nested case-control studies, and 3 cohort studies were included in the final analyses. The pooled odds ratio (OR) for fracture was 1.29 (95% confidence interval [CI], 1.18-1.41) with use of PPIs and 1.10 (95% CI, 0.99-1.23) with use of H(2)RAs when compared with nonuse of the respective medications. Long-term use of PPIs increased the risk of any fracture (adjusted OR = 1.30; 95% CI, 1.15-1.48) and hip fracture risk (adjusted OR = 1.34; 95% CI, 1.09-1.66), whereas long-term H(2)RA use was not significantly associated with fracture risk. We found possible evidence linking PPI use to an increased risk of fracture, but no association between H(2)RA use and fracture risk. Widespread use of PPIs with the potential risk of fracture is of great importance to public health. Clinicians should carefully consider their decision to prescribe PPIs for patients already having an elevated risk of fracture because of age or other factors.

Genome-wide copy number variation study associates metabotropic glutamate receptor gene networks with attention deficit hyperactivity disorder

PubMed Central

Elia, Josephine; Glessner, Joseph T; Wang, Kai; Takahashi, Nagahide; Shtir, Corina J; Hadley, Dexter; Sleiman, Patrick M A; Zhang, Haitao; Kim, Cecilia E; Robison, Reid; Lyon, Gholson J; Flory, James H; Bradfield, Jonathan P; Imielinski, Marcin; Hou, Cuiping; Frackelton, Edward C; Chiavacci, Rosetta M; Sakurai, Takeshi; Rabin, Cara; Middleton, Frank A; Thomas, Kelly A; Garris, Maria; Mentch, Frank; Freitag, Christine M; Steinhausen, Hans-Christoph; Todorov, Alexandre A; Reif, Andreas; Rothenberger, Aribert; Franke, Barbara; Mick, Eric O; Roeyers, Herbert; Buitelaar, Jan; Lesch, Klaus-Peter; Banaschewski, Tobias; Ebstein, Richard P; Mulas, Fernando; Oades, Robert D; Sergeant, Joseph; Sonuga-Barke, Edmund; Renner, Tobias J; Romanos, Marcel; Romanos, Jasmin; Warnke, Andreas; Walitza, Susanne; Meyer, Jobst; Pálmason, Haukur; Seitz, Christiane; Loo, Sandra K; Smalley, Susan L; Biederman, Joseph; Kent, Lindsey; Asherson, Philip; Anney, Richard J L; Gaynor, J William; Shaw, Philip; Devoto, Marcella; White, Peter S; Grant, Struan F A; Buxbaum, Joseph D; Rapoport, Judith L; Williams, Nigel M; Nelson, Stanley F; Faraone, Stephen V; Hakonarson, Hakon

2014-01-01

Attention deficit hyperactivity disorder (ADHD) is a common, heritable neuropsychiatric disorder of unknown etiology. We performed a whole-genome copy number variation (CNV) study on 1,013 cases with ADHD and 4,105 healthy children of European ancestry using 550,000 SNPs. We evaluated statistically significant findings in multiple independent cohorts, with a total of 2,493 cases with ADHD and 9,222 controls of European ancestry, using matched platforms. CNVs affecting metabotropic glutamate receptor genes were enriched across all cohorts (P = 2.1 × 10−9). We saw GRM5 (encoding glutamate receptor, metabotropic 5) deletions in ten cases and one control (P = 1.36 × 10−6). We saw GRM7 deletions in six cases, and we saw GRM8 deletions in eight cases and no controls. GRM1 was duplicated in eight cases. We experimentally validated the observed variants using quantitative RT-PCR. A gene network analysis showed that genes interacting with the genes in the GRM family are enriched for CNVs in ~10% of the cases (P = 4.38 × 10−10) after correction for occurrence in the controls. We identified rare recurrent CNVs affecting glutamatergic neurotransmission genes that were overrepresented in multiple ADHD cohorts. PMID:22138692

Does BCG vaccine prevent tuberculous meningitis?

PubMed Central

Thilothammal, N; Krishnamurthy, P V; Runyan, D K; Banu, K

1996-01-01

The reported efficacy of BCG vaccine in preventing pulmonary tuberculosis varies from 0-80%; however, its efficacy in preventing tuberculous meningitis ranges from 52%-84%. A case-control study was conducted to assess the efficacy of BCG in preventing tuberculous meningitis in children. New cases of tuberculous meningitis, confirmed bacteriologically, were registered as cases. Controls were children suffering from febrile convulsions attending the same hospital. A total of 107 cases and 321 controls, block matched for age, were registered. Vaccination status was determined from the history reported by the mother and by BCG scar reading. Data regarding socioeconomic status, crowding, and nutritional status were collected. Using multiple logistic regression analysis the odds ratio obtained for the presence of BCG scar was 0.23 (95% confidence interval (CI) 0.14 to 0.37) and the protective efficacy of BCG vaccine in preventing tuberculous meningitis in children was found to be 77% (95% CI 71 to 83%). PMID:8660078

SULT1A1 Arg213His polymorphism, smoked meat, and breast cancer risk: a case-control study and meta-analysis.

PubMed

Lee, Hui; Wang, Qiong; Yang, Fei; Tao, Ping; Li, Hui; Huang, Yuan; Li, Jia-Yuan

2012-05-01

SULT1A1 is involved in both detoxification of estrogens and bioactivation of carcinogens in smoked meat. SULT1A1 Arg213His polymorphism's effect on breast cancer risk is still unclear. We recruited 400 case-control pairs to investigate the association between SULT1A1 genotypes and breast cancer risk, and the combined effect of SULT1A1 polymorphism and daily intake of smoked meat. Participants were questioned about their dietary habits and other risk factors, and their SULT1A1 genotypes were determined. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were estimated by multivariable unconditional logistic regression. We also performed a meta-analysis of relevant published studies to test these associations. In the case-control study, no significant associations were observed between SULT1A1 polymorphism and breast cancer risk. In the meta-analysis, SULT1A1 His/His genotype slightly increased risk among both overall and postmenopausal women (OR(pooled-overall)=1.12, 95% CI: 1.02-1.24; OR(pooled-post)=1.17, 95% CI: 1.03-1.32). A larger positive association was observed in Asian populations (OR(pooled-Asian)=2.01, 95% CI: 1.24-3.26). In our case-control study, high energy-adjusted daily intake of smoked meat was significantly associated with breast cancer risk in overall, pre- and postmenopausal women (aORs: 2.31-3.13, OR 95% CIs exclude 1). High smoked meat intake interacted positively with the His variant allele (all γ>1). These results correlated with those of the meta-analysis (γ(pooled-overall)=1.27). The SULT1A1 His/His genotype may increase the risk of breast cancer among Asian women, and dietary exposure to heterocyclic amines and polycyclic aromatic hydrocarbons, along with the SULT1A1 His/His variant genotype, may synergistically increase the risk of breast cancer.

Vaccines are not associated with autism: an evidence-based meta-analysis of case-control and cohort studies.

PubMed

Taylor, Luke E; Swerdfeger, Amy L; Eslick, Guy D

2014-06-17

There has been enormous debate regarding the possibility of a link between childhood vaccinations and the subsequent development of autism. This has in recent times become a major public health issue with vaccine preventable diseases increasing in the community due to the fear of a 'link' between vaccinations and autism. We performed a meta-analysis to summarise available evidence from case-control and cohort studies on this topic (MEDLINE, PubMed, EMBASE, Google Scholar up to April, 2014). Eligible studies assessed the relationship between vaccine administration and the subsequent development of autism or autism spectrum disorders (ASD). Two reviewers extracted data on study characteristics, methods, and outcomes. Disagreement was resolved by consensus with another author. Five cohort studies involving 1,256,407 children, and five case-control studies involving 9,920 children were included in this analysis. The cohort data revealed no relationship between vaccination and autism (OR: 0.99; 95% CI: 0.92 to 1.06) or ASD (OR: 0.91; 95% CI: 0.68 to 1.20), nor was there a relationship between autism and MMR (OR: 0.84; 95% CI: 0.70 to 1.01), or thimerosal (OR: 1.00; 95% CI: 0.77 to 1.31), or mercury (Hg) (OR: 1.00; 95% CI: 0.93 to 1.07). Similarly the case-control data found no evidence for increased risk of developing autism or ASD following MMR, Hg, or thimerosal exposure when grouped by condition (OR: 0.90, 95% CI: 0.83 to 0.98; p=0.02) or grouped by exposure type (OR: 0.85, 95% CI: 0.76 to 0.95; p=0.01). Findings of this meta-analysis suggest that vaccinations are not associated with the development of autism or autism spectrum disorder. Furthermore, the components of the vaccines (thimerosal or mercury) or multiple vaccines (MMR) are not associated with the development of autism or autism spectrum disorder. Copyright © 2014 Elsevier Ltd. All rights reserved.

Mapping a New Spontaneous Preterm Birth Susceptibility Gene, IGF1R, Using Linkage, Haplotype Sharing, and Association Analysis

PubMed Central

Luukkonen, Aino; Teramo, Kari; Puttonen, Hilkka; Ojaniemi, Marja; Varilo, Teppo; Chaudhari, Bimal P.; Plunkett, Jevon; Murray, Jeffrey C.; McCarroll, Steven A.; Muglia, Louis J.; Palotie, Aarno; Hallman, Mikko

2011-01-01

Preterm birth is the major cause of neonatal death and serious morbidity. Most preterm births are due to spontaneous onset of labor without a known cause or effective prevention. Both maternal and fetal genomes influence the predisposition to spontaneous preterm birth (SPTB), but the susceptibility loci remain to be defined. We utilized a combination of unique population structures, family-based linkage analysis, and subsequent case-control association to identify a susceptibility haplotype for SPTB. Clinically well-characterized SPTB families from northern Finland, a subisolate founded by a relatively small founder population that has subsequently experienced a number of bottlenecks, were selected for the initial discovery sample. Genome-wide linkage analysis using a high-density single-nucleotide polymorphism (SNP) array in seven large northern Finnish non-consanginous families identified a locus on 15q26.3 (HLOD 4.68). This region contains the IGF1R gene, which encodes the type 1 insulin-like growth factor receptor IGF-1R. Haplotype segregation analysis revealed that a 55 kb 12-SNP core segment within the IGF1R gene was shared identical-by-state (IBS) in five families. A follow-up case-control study in an independent sample representing the more general Finnish population showed an association of a 6-SNP IGF1R haplotype with SPTB in the fetuses, providing further evidence for IGF1R as a SPTB predisposition gene (frequency in cases versus controls 0.11 versus 0.05, P = 0.001, odds ratio 2.3). This study demonstrates the identification of a predisposing, low-frequency haplotype in a multifactorial trait using a well-characterized population and a combination of family and case-control designs. Our findings support the identification of the novel susceptibility gene IGF1R for predisposition by the fetal genome to being born preterm. PMID:21304894

The Prothrombin G20210A Mutation is Associated with Young-Onset Stroke: The Genetics of Early Onset Stroke Study and Meta-Analysis

PubMed Central

Jiang, Baijia; Ryan, Kathleen A.; Hamedani, Ali; Cheng, Yuching; Sparks, Mary J.; Koontz, Deborah; Bean, Christopher J.; Gallagher, Margaret; Hooper, W. Craig; McArdle, Patrick F.; O'Connell, Jeffrey R.; Stine, O. Colin; Wozniak, Marcella A.; Stern, Barney J.; Mitchell, Braxton D.; Kittner, Steven J.; Cole, John W.

2014-01-01

Background and Purpose Although the prothrombin G20210A mutation has been implicated as a risk factor for venous thrombosis, its role in arterial ischemic stroke is unclear, particularly among young-adults. To address this issue, we examined the association between prothrombin G20210A and ischemic stroke in a Caucasian case-control population and additionally performed a meta-analysis Methods From the population-based Genetics of Early Onset Stroke (GEOS) study we identified 397 individuals of European ancestry aged 15-49 years with first-ever ischemic stroke and 426 matched-controls. Logistic regression was used to calculate odds ratios in the entire population and for subgroups stratified by gender, age, oral contraceptive use, migraine and smoking status. A meta-analysis of 17 case-control studies (n=2305 cases <55 years) was also performed with and without GEOS data. Results Within GEOS, the association of the prothrombin G20210A mutation with ischemic stroke did not achieve statistical significance (OR=2.5,95%CI=0.9-6.5,p=0.07). However, among adults aged 15-42 (younger than median age), cases were significantly more likely than controls to have the mutation (OR=5.9,95%CI=1.2-28.1,p=0.03), whereas adults ages 42-49 were not (OR=1.4,95%CI=0.4-5.1,p=0.94). In our meta-analysis, the mutation was associated with significantly increased stroke risk in adults <=55 years (OR=1.4;95%CI=1.1-1.9;p=0.02) with significance increasing with addition of the GEOS results (OR=1.5;95%CI=1.1-2.0;p=0.005). Conclusions The prothrombin G20210A mutation is associated with ischemic stroke in young-adults and may have an even stronger association among those with earlier onset strokes. Our finding of a stronger association in the younger-young adult population requires replication. PMID:24619398

Decision curve analysis revisited: overall net benefit, relationships to ROC curve analysis, and application to case-control studies.

PubMed

Rousson, Valentin; Zumbrunn, Thomas

2011-06-22

Decision curve analysis has been introduced as a method to evaluate prediction models in terms of their clinical consequences if used for a binary classification of subjects into a group who should and into a group who should not be treated. The key concept for this type of evaluation is the "net benefit", a concept borrowed from utility theory. We recall the foundations of decision curve analysis and discuss some new aspects. First, we stress the formal distinction between the net benefit for the treated and for the untreated and define the concept of the "overall net benefit". Next, we revisit the important distinction between the concept of accuracy, as typically assessed using the Youden index and a receiver operating characteristic (ROC) analysis, and the concept of utility of a prediction model, as assessed using decision curve analysis. Finally, we provide an explicit implementation of decision curve analysis to be applied in the context of case-control studies. We show that the overall net benefit, which combines the net benefit for the treated and the untreated, is a natural alternative to the benefit achieved by a model, being invariant with respect to the coding of the outcome, and conveying a more comprehensive picture of the situation. Further, within the framework of decision curve analysis, we illustrate the important difference between the accuracy and the utility of a model, demonstrating how poor an accurate model may be in terms of its net benefit. Eventually, we expose that the application of decision curve analysis to case-control studies, where an accurate estimate of the true prevalence of a disease cannot be obtained from the data, is achieved with a few modifications to the original calculation procedure. We present several interrelated extensions to decision curve analysis that will both facilitate its interpretation and broaden its potential area of application.

Decision curve analysis revisited: overall net benefit, relationships to ROC curve analysis, and application to case-control studies

PubMed Central

2011-01-01

Background Decision curve analysis has been introduced as a method to evaluate prediction models in terms of their clinical consequences if used for a binary classification of subjects into a group who should and into a group who should not be treated. The key concept for this type of evaluation is the "net benefit", a concept borrowed from utility theory. Methods We recall the foundations of decision curve analysis and discuss some new aspects. First, we stress the formal distinction between the net benefit for the treated and for the untreated and define the concept of the "overall net benefit". Next, we revisit the important distinction between the concept of accuracy, as typically assessed using the Youden index and a receiver operating characteristic (ROC) analysis, and the concept of utility of a prediction model, as assessed using decision curve analysis. Finally, we provide an explicit implementation of decision curve analysis to be applied in the context of case-control studies. Results We show that the overall net benefit, which combines the net benefit for the treated and the untreated, is a natural alternative to the benefit achieved by a model, being invariant with respect to the coding of the outcome, and conveying a more comprehensive picture of the situation. Further, within the framework of decision curve analysis, we illustrate the important difference between the accuracy and the utility of a model, demonstrating how poor an accurate model may be in terms of its net benefit. Eventually, we expose that the application of decision curve analysis to case-control studies, where an accurate estimate of the true prevalence of a disease cannot be obtained from the data, is achieved with a few modifications to the original calculation procedure. Conclusions We present several interrelated extensions to decision curve analysis that will both facilitate its interpretation and broaden its potential area of application. PMID:21696604

Flash flood disasters analysis and evaluation: a case study of Yiyang County in China

NASA Astrophysics Data System (ADS)

Li, Haichen; Zhang, Xiaolei; Li, Qing; Qin, Tao; Lei, Xiaohui

2018-03-01

Global climate change leads to the more extreme precipitation and more flash flood disasters, which is a serious threat to the mountain inhabitants. To prevent flash flood disasters, China started flash flood disaster control planning and other projects from 2006. Among those measures, non-engineering measures are effective and economical. This paper introduced the framework of flash flood disaster analysis and evaluation in China, followed by a case study of Yiyang County.

[The value of lidocaine through different routes of administration in the treatment of tinnitus: a Meta-analysis].

PubMed

Li, Hui; Li, Ming; Zhang, Jianning; Li, Xiangcui; Tan, Junying; Ji, Bobo

2016-01-01

To evaluate the clinical value of lidocain in the treatment of tinnitus through three routes of administration (intravenous, intratympanic and acupoint injection) by analyzing literatures. Articles were collected through Hownet, Wanfang, VIP, Pubmed, SciVerse ScienceDirect, Springer and OVID, etc. The articles were strictly evaluated based on their quality. The Meta-analysis was performed to evaluate the outcomes by RevMan 5. 2 software. A total of 16 articles with 1203 patients were enrolled in the analysis. Their tinnitus history ranged from 7 hours to 20 years. Assessment methods include tinnitus loudness levels, severity scales and subjective feelings. None of articles refer to maintaining time, instead of "short-term", "short" and so on. A total of 133 cases received intravenous injection and the effective rate was 73.4% (98 cases). 50 cases and 332 cases received intratympanic and acupoint injection respectively and their effective rates were 74.0% and 87.7%, respectively. The effective rate ranged from 42.4% to 58.3% in control group. Meta-analysis results indicate that all three routes of lidocaine administrations are more effective than conventional methods (P < 0.05). Different routes of lidocaine administration have a good but short time effects on the tinnitus control. It can effectively reduce the time of tinnitus habituation as a complementary treatment. But its value still needs further evaluation.

Lung cancer risk among bricklayers in a pooled analysis of case–control studies

PubMed Central

Consonni, Dario; Matteis, Sara De; Pesatori, Angela C; Bertazzi, Pier Alberto; Olsson, Ann C; Kromhout, Hans; Peters, Susan; Vermeulen, Roel CH; Pesch, Beate; Brüning, Thomas; Kendzia, Benjamin; Behrens, Thomas; Stücker, Isabelle; Guida, Florence; Wichmann, Heinz-Erich; Brüske, Irene; Landi, Maria Teresa; Caporaso, Neil E; Gustavsson, Per; Plato, Nils; Tse, Lap Ah; Yu, Ignatius Tak-sun; Jöckel, Karl-Heinz; Ahrens, Wolfgang; Pohlabeln, Hermann; Merletti, Franco; Richiardi, Lorenzo; Simonato, Lorenzo; Forastiere, Francesco; Siemiatycki, Jack; Parent, Marie-Élise; Tardón, Adonina; Boffetta, Paolo; Zaridze, David; Chen, Ying; Field, John K; 't Mannetje, Andrea; Pearce, Neil; McLaughlin, John; Demers, Paul; Lissowska, Jolanta; Szeszenia-Dabrowska, Neonila; Bencko, Vladimir; Foretova, Lenka; Janout, Vladimir; Rudnai, Peter; Fabiánová, Eleonóra; Stanescu Dumitru, Rodica; Bueno-de-Mesquita, H B(as); Schüz, Joachim; Straif, Kurt

2015-01-01

Bricklayers may be exposed to several lung carcinogens, including crystalline silica and asbestos. Previous studies that analyzed lung cancer risk among these workers had several study design limitations. We examined lung cancer risk among bricklayers within SYNERGY, a large international pooled analysis of case–control studies on lung cancer and the joint effects of occupational carcinogens. For men ever employed as bricklayers we estimated odds ratios (OR) and 95% confidence intervals (CI) adjusted for study center, age, lifetime smoking history and employment in occupations with exposures to known or suspected lung carcinogens. Among 15,608 cases and 18,531 controls, there were 695 cases and 469 controls who had ever worked as bricklayers (OR: 1.47; 95% CI: 1.28–1.68). In studies using population controls the OR was 1.55 (95% CI: 1.32–1.81, 540/349 cases/controls), while it was 1.24 (95% CI: 0.93–1.64, 155/120 cases/controls) in hospital-based studies. There was a clear positive trend with length of employment (p < 0.001). The relative risk was higher for squamous (OR: 1.68, 95% CI: 1.42–1.98, 309 cases) and small cell carcinomas (OR: 1.78, 95% CI: 1.44–2.20, 140 cases), than for adenocarcinoma (OR: 1.17, 95% CI: 0.95–1.43, 150 cases) (p-homogeneity: 0.0007). ORs were still elevated after additional adjustment for education and in analyses using blue collar workers as referents. This study provided robust evidence of increased lung cancer risk in bricklayers. Although non-causal explanations cannot be completely ruled out, the association is plausible in view of the potential for exposure to several carcinogens, notably crystalline silica and to a lesser extent asbestos. What's new? In their work, bricklayers can be exposed to various airborne carcinogens, including crystalline silica and asbestos. Previous studies of cancer risk have not accounted for full employment history or smoking status, and failed to establish a firm relationship between bricklaying and lung cancer. In this study, the authors used data from the largest collection of case-control studies on lung cancer with complete occupational and smoking history existing today, the SYNERGY project. They found clear evidence that lung cancer risk increases in proportion to the length of time spent working as a bricklayer, paving the way for better protection and compensation for those in this occupation. PMID:24861979

Indoor dampness and molds and development of adult-onset asthma: a population-based incident case-control study.

PubMed Central

Jaakkola, Maritta S; Nordman, Henrik; Piipari, Ritva; Uitti, Jukka; Laitinen, Jukka; Karjalainen, Antti; Hahtola, Paula; Jaakkola, Jouni J K

2002-01-01

Previous cross-sectional and prevalent case-control studies have suggested increased risk of asthma in adults related to dampness problems and molds in homes. We conducted a population-based incident case-control study to assess the effects of indoor dampness problems and molds at work and at home on development of asthma in adults. We recruited systematically all new cases of asthma during a 2.5-year study period (1997-2000) and randomly selected controls from a source population consisting of adults 21-63 years old living in the Pirkanmaa Hospital district, South Finland. The clinically diagnosed case series consisted of 521 adults with newly diagnosed asthma and the control series of 932 controls, after we excluded 76 (7.5%) controls with a history of asthma. In logistic regression analysis adjusting for confounders, the risk of asthma was related to the presence of visible mold and/or mold odor in the workplace (odds ratio, 1.54; 95% confidence interval, 1.01-2.32) but not to water damage or damp stains alone. We estimated the fraction of asthma attributable to workplace mold exposure to be 35.1% (95% confidence interval, 1.0-56.9%) among the exposed. Present results provide new evidence of the relation between workplace exposure to indoor molds and adult-onset asthma. PMID:12003761

A Business Case for Nuclear Plant Control Room Modernization

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

Thomas, Ken; Lawrie, Sean; Niedermuller, Josef M.

This paper presents a generic business case for implementation of technology that supports Control Room Modernization (CRM). The analysis presented in two forms; 1) a standalone technology upgrade, and 2) a technology upgrade that is built upon and incremental to a prior business case created for Mobile Work Packages (MWP). The business case contends that advanced communication and networking and analytical technologies will allow NPP to conduct control room operations with improved focus by reducing human factors and redundant manpower, and therefore operate with fewer errors. While some labor savings can be harvested in terms of overtime, the majority ofmore » savings are demonstrated as reduced time to take the plant off line and bring back on line in support of outages. The benefits are quantified to a rough order of magnitude that provides directional guidance to NPPs that are interested in developing a similar business case. This business case focuses on modernization of the operator control room and does not consider a complete overhaul and modernization of a plants instrument and control systems. While operators may be considering such an investment at their plants, the sizable capital investment required is not likely supported by a cost/benefit analysis alone. More likely, it is driven by obsolescence and reliability issues, and requires consideration of mechanical condition of plant systems, capital depreciation, financing, relicensing and overall viability of the plant asset over a 20-year horizon in a competitive market. Prior studies [REF] have indicated that such a modernization of plant I&C systems, alone or as part of a larger modernization effort, can yield very significant reductions in O&M costs. However, the depth of research and analysis required to develop a meaningful business case for a plant modernization effort is well beyond the scope of this study. While CRM as considered in this study can be easily integrated as part of grander plant modernization effort, it can also be considered as a stand-alone project, implemented as a supervisorial layer over and above existing systems. CRM is enabled by a suite of technologies, which are described in further detail in the body of this report. They include: • Modernized control room with interactive displays • High-bandwidth wireless networks • Mobile devices • Component identification technology • Mobile wireless video cameras • Smart or task based operator displays • Computer-Based Procedures (CBP)/Automated Mobile Work Packages (MWP) • Intelligent plant configuration • Advanced data analytics An analysis was conducted to determine how these technologies might impact outage operations at an NPP. The analysis concluded that outage management capabilities would be improved with application of these technologies, and result in annual benefits for the plant. These improved capabilities were identified and described in further detail in this report. • Reduction in need redundant manpower (verification, etc) • Improved critical path shutdown and restart duration during outages • Reduction in human factors and errors • Remote watches • Paperless outage coordination • Bulk work optimization« less

[Arterial hypertension and sleep apnea hypopnea syndrome in primary care].

PubMed

Bayó Llibre, J; Riel Cabrera, R; Mellado Breña, E; Filomena Paci, J; Priego Artero, M; García Alfaro, F J; Grau Granero, J M; Vázquez González, D; López Solana, J; Fernández San Martín, M I

2015-01-01

Sleep apnea hypopnea syndrome (SAHS) is frequent in hypertensive patients and plays a role in a greater incidence of cardiovascular morbidity-mortality. This study aims to know the clinical profile of hypertensive patients with SAHS compared to hypertensive patients without SAHS to know which variables should be used to orient their screening from primary care. An observational, descriptive, retrospective study of cases (hypertensive patients with SAHS) and controls (hypertensive patients without) was performed in an urban health care center. Based on a computerized registry of the site, patients diagnosed of SAHS and hypertension over 30 years of age were selected. For each case, one control case of hypertensive patients without SAHS paired by age and gender was randomly obtained. A total of 64 cases and 64 controls were selected. Standing out in the bivariate analysis were greater BMI (34.3±12.8 vs. 28.6±3.6), predominance of obesity (70.3 vs. 35.9%), metabolic syndrome (77.3 vs. 42.2%), consumption of psychopharmaceuticals (19.7 vs. 7.8%) and anithypertensive drugs (26.5 vs. 14.0%), ischemic heart disease (20.3 vs. 9.4%) in the case group versus control group (P<.05 for all the variables). The multivariate analysis showed that only the presence of metabolic syndrome was related with the presence of SAHS in hypertensive patients (OR 4.65; 95% CI: 2.03-10.64; P<.001). Screening for SAHS should be performed in hypertensive patients seen in primary care if they have metabolic syndrome criteria. Copyright © 2014 SEHLELHA. Published by Elsevier Espana. All rights reserved.

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.

Gender Differences in Hiccup Patients: Analysis of Published Case Reports and Case-Control Studies.

PubMed

Lee, Gyeong-Won; Kim, Rock Bum; Go, Se Il; Cho, Hyun Seop; Lee, Seung Jun; Hui, David; Bruera, Eduardo; Kang, Jung Hun

2016-02-01

Although sporadic male predominance in hiccup patients has been reported, the association between gender differences and triggering factors has rarely been evaluated in patients with hiccups. The aim of this study was to investigate whether gender differences exist in hiccup patients by analyzing all previously published hiccup literature containing gender and etiology information. Published literature on this topic was identified using a standardized search strategy in the PubMed, SCOPUS, and CINAHL electronic databases. The literature search included studies published from January 1990 to December 2013. Searches were limited to English-language publications. Of 476 identified studies, 318 studies were eligible including eight case-control studies that contained nonhiccup control groups. Triggering factors for hiccups were categorized into two types: central nervous system (CNS) and non-CNS causes. Odds ratios (ORs) were calculated for the eight case-control studies and event rates for the other studies by meta-analysis. In addition, gender differences and mean ages were analyzed for the case studies. Pooled OR was 2.42 (95% confidence interval [CI] 1.40-4.17) with inclination for male predominance. Subgroup analysis by cause showed clear male predominance in the non-CNS type with OR of 11.72 (95% CI 3.16-43.50), whereas indistinct in the CNS type with OR of 1.74 (95% CI 0.95-3.16). Of the remaining 310 studies with 864 patients, previous findings were consistent. Male predominance was consistent in non-CNS (85.1%, 95% CI 78.2-90.2) and unknown origin (82.2%, 95% CI 75.8-87.2) patients, whereas mitigating the sex discrepancy in those with CNS origin (65.8%, 95% CI 53.1-76.5). We demonstrated male predominance in hiccup patients. This gender difference for hiccups was more pronounced in patients with non-CNS causes, whereas indistinct in patients with CNS causes. Copyright © 2016 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.

[Association between mothers' body mass index before pregnancy or weight gain during pregnancy and autism in children].

PubMed

Ling, Ziyu; Wang, Jianmin; Li, Xia; Zhong, Yan; Qin, Yuanyuan; Xie, Shengnan; Yang, Senbei; Zhang, Jing

2015-09-01

To explore the relationship between mothers' body mass index (BMI) before pregnancy or weight gain during pregnancy and autism in children. From 2013 to 2014, the 181 children with autism and 181 healthy children matched by sex and age from same area were included in this study. According to mothers' BMI before pregnancy, the selected cases were divided into 3 groups: low, normal and high group. Then 3 groups were divided into 3 subgroups based on mother' s weight gain during pregnancy: low, normal and high group, according to the recommendations of Institute of Medicine. Logistic regression analysis and χ(2) test were conducted with SPSS 18.0 software to analysis the relationship between mothers' BMI before pregnancy or weight gain during pregnancy and autism in children. The age and sex distributions of case group and control group were consistent (χ(2)=0.434, P>0.05). The mothers' BMI before pregnancy of case group was higher than that of control group (χ(2)=9.580, P<0.05) ,which was (21.28±3.80) kg/m(2) for case group and (19.87±2.83) kg/m(2) for control group. The proportion of cases in high BMI group (10.5%) was much higher than that in control group (2.8%) . The risk of children with autism in high BMI group was 3.7 times higher than that in normal BMI group (OR=3.71, 95% CI: 1.34-10.24). In normal BMI group, the proportion of mothers who had excessive weight gain during pregnancy was higher in case group (44.1%) than in control group (33.9%). In high BMI group, the proportion of mothers who had excessive weight gain was higher in case group (52.6%) than in control group (20.0%) . In normal BMI group (χ(2) =8.690, P<0.05) and high BMI group (χ(2)=4.775, P<0.05), the weight gain during pregnancy was associated with autism in children. Logistic regression analysis showed that mothers' BMI before pregnancy (unadjusted OR=1.89, 95% CI: 1.26-2.85, adjusted OR=1.52, 95% CI: 1.19-2.27) and weight gain during pregnancy were the risk factors for autism in children (unadjusted OR=1.63, 95% CI: 1.08-1.25, adjusted OR=1.64, 95% CI: 1.21-2.21). Overweight or obesity before pregnancy and excessive weight gain during pregnancy were associated with autism in children, suggesting that women who plan to be pregnant should pay attention to body weight control.

The Association Between Neurocysticercosis and Hippocampal Atrophy is Related to Age

PubMed Central

Del Brutto, Oscar H.; Issa, Naoum P.; Salgado, Perla; Del Brutto, Victor J.; Zambrano, Mauricio; Lama, Julio; García, Héctor H.

2017-01-01

Neurocysticercosis (NCC) has been associated with hippocampal atrophy, but the prevalence and pathogenic mechanisms implicated in this relationship are unknown. Using a population-based, case–control study design, residents in a rural village (Atahualpa) aged ≥ 40 years with calcified NCC were identified as cases and paired to NCC-free individuals (control subjects) matched by age, sex, and level of education. Cases and control subjects underwent magnetic resonance imaging for hippocampal rating according to the Scheltens' scale for medial temporal atrophy and were interviewed to identify those with a clinical seizure disorder. The prevalence of hippocampal atrophy was compared between cases and control subjects by the use of the McNemar's test for correlated proportions. Seventy-five individuals with calcified NCC and their matched control subjects were included in the analysis. Hippocampal atrophy was noted in 26 (34.7%) cases and nine (12%) control subjects (odds ratio: 4.4; 95% confidence interval: 1.6–14.9, P < 0.0021). Stratification of pairs according to tertiles of age revealed an age-related trend in this association, which became significant only in those aged ≥ 68 years (P = 0.027). Only five cases and one control had recurrent seizures (P = 0.221); three of these five cases had hippocampal atrophy, and the single control subject had normal hippocampi. This study confirms an association between NCC and hippocampal atrophy, and shows that this association is stronger in older age groups. This suggests that NCC-related hippocampal atrophy takes a long time to develop. PMID:28077750

No association of SORL1 SNPs with Alzheimer's disease.

PubMed

Minster, Ryan L; DeKosky, Steven T; Kamboh, M Ilyas

2008-08-01

SORL1 is an element of the amyloid precursor protein processing pathway and is therefore a good candidate for affecting Alzheimer's disease (AD) risk. Indeed, there have been reports of associations between variation in SORL1 and AD risk. We examined six statistically significant single-nucleotide polymorphisms from the initial observation in a large Caucasian American case-controls cohort (1000 late-onset AD [LOAD] cases and 1000 older controls). Analysis of allele, genotype and haplotype frequencies revealed no association with LOAD risk in our cohort.

The reduction of a ""safety catastrophic'' potential hazard: A case history

NASA Technical Reports Server (NTRS)

Jones, J. P.

1971-01-01

A worst case analysis is reported on the safety of time watch movements for triggering explosive packages on the lunar surface in an experiment to investigate physical lunar structural characteristics through induced seismic energy waves. Considered are the combined effects of low pressure, low temperature, lunar gravity, gear train error, and position. Control measures constitute a seal control cavity and design requirements to prevent overbanking in the mainspring torque curve. Thus, the potential hazard is reduced to safety negligible.

Maternal butalbital use and selected defects in the national birth defects prevention study.

PubMed

Browne, Marilyn L; Van Zutphen, Alissa R; Botto, Lorenzo D; Louik, Carol; Richardson, Sandra; Druschel, Charlotte M

2014-01-01

Butalbital is a barbiturate contained in combination products with caffeine and an analgesic prescribed for the treatment of migraine and tension-type headaches. Controversy exists as to whether butalbital should continue to be prescribed in the United States because of the potential for abuse, overuse headache, and withdrawal syndromes. Butalbital crosses the placenta but there is limited information about potential teratogenicity. To evaluate associations between butalbital and a wide range of specific birth defects. The National Birth Defects Prevention Study is an ongoing, case-control study of nonsyndromic, major birth defects conducted in 10 states. The detailed case classification and large number of cases in the National Birth Defects Prevention Study allowed us to examine the association between maternal self-reported butalbital use and specific birth defects. We conducted an analysis of 8373 unaffected controls and 21,090 case infants with estimated dates of delivery between 1997 and 2007; included were birth defects with 250 or more cases. An exploratory analysis examined groups with 100 to 249 cases. Seventy-three case mothers and 15 control mothers reported periconceptional butalbital use. Of 30 specific defect groups evaluated, adjusted odds ratios for maternal periconceptional butalbital use were statistically significant for 3 congenital heart defects: tetralogy of Fallot (adjusted odds ratio = 3.04; 95% confidence interval = 1.07-8.62), pulmonary valve stenosis (adjusted odds ratio = 5.73; 95% confidence interval = 2.25-14.62), and secundum-type atrial septal defect (adjusted odds ratio = 3.06; 95% confidence interval = 1.07-8.79). In the exploratory analysis, an elevated odds ratio was detected for 1 congenital heart defect, single ventricle. We observed relationships between maternal periconceptional butalbital use and certain congenital heart defects. These associations have not been reported before, and some may be spurious. Butalbital use was rare and despite the large size of the National Birth Defects Prevention Study, the number of exposed case and control infants was small. However, if confirmed in additional studies, our findings will be useful in weighing the risks and benefits of butalbital for the treatment of migraine and tension-type headaches. © Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

Consumption of different types of meat and the risk of renal cancer: meta-analysis of case-control studies.

PubMed

Faramawi, Mohammed F; Johnson, Eric; Fry, M Whitney; Sall, Macodu; Zhou, Yi; Yi, Zhou

2007-03-01

Kidney cancers account for almost 2% of all cancers worldwide, with 150,000 new cases and 78,000 deaths from the disease occurring annually. An increase in the incidence of kidney neoplasm in western countries was noticed in the past few years. Between 1988 and 1992, the incidence of renal cancer per 100,000 person-year among males in USA, Norway, and France was 34.1, 9.00, and 16.10, respectively. Among females in the same countries, it was 5.70, 5.00, and 7.30, respectively. Although several individual case-control studies examined the association of meat intake and renal cancer risk, the results were inconsistent because of the insufficient statistical power of the individual studies. Therefore, the following meta-analysis was designed to help in clarifying the association. Electronic search of MEDLINE, OVID, and PUBMED databases which have articles published between (1966 and 2006) was conducted to select studies for this meta-analysis. Fixed and random-effects meta-analytical techniques were used to estimate the overall association between meat consumption and kidney cancer. Thirteen case-control studies were found. This meta-analysis supported a positive relationship between meat consumption and risk of renal cancer. Summary results indicated that there was from 20% to 22% higher risk of renal cancer among those in the highest relative to the lowest category of poultry and processed meat consumption. Consumption of all meat and red meat was associated with 27% and 30% higher risk, respectively. The increased risks were statistically significant. Increased consumption of all meat, red meat, poultry, and processed meat is associated with an increase risk of kidney cancer. Reduction of meat consumption is an important approach to decreasing the incidence of kidney cancer in the general population.

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.

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

PubMed

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

2010-08-01

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

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

PubMed

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

2017-05-01

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

The inevitability of normative analysis.

PubMed

Sarkar, Sahotra

2014-08-01

Wilson et al. make the case for taking control of our future using evolutionary analysis. However, they are entirely silent on the ethical questions that must be addressed. This piece emphasizes this problem and notes that the relevant answers will require nontrivial analysis. This is where the humanities become relevant - in particular, philosophy and cultural anthropology.

Computational algebraic geometry of epidemic models

NASA Astrophysics Data System (ADS)

Rodríguez Vega, Martín.

2014-06-01

Computational Algebraic Geometry is applied to the analysis of various epidemic models for Schistosomiasis and Dengue, both, for the case without control measures and for the case where control measures are applied. The models were analyzed using the mathematical software Maple. Explicitly the analysis is performed using Groebner basis, Hilbert dimension and Hilbert polynomials. These computational tools are included automatically in Maple. Each of these models is represented by a system of ordinary differential equations, and for each model the basic reproductive number (R0) is calculated. The effects of the control measures are observed by the changes in the algebraic structure of R0, the changes in Groebner basis, the changes in Hilbert dimension, and the changes in Hilbert polynomials. It is hoped that the results obtained in this paper become of importance for designing control measures against the epidemic diseases described. For future researches it is proposed the use of algebraic epidemiology to analyze models for airborne and waterborne diseases.

Increased CNV-Region deletions in mild cognitive impairment (MCI) and Alzheimer's disease (AD) subjects in the ADNI sample

PubMed Central

Guffanti, Guia; Torri, Federica; Rasmussen, Jerod; Clark, Andrew P.; Lakatos, Anita; Turner, Jessica A.; Fallon, James H.; Saykin, Andrew J.; Weiner, Michael; Vawter, Marquis P.; Knowles, James A.; Potkin, Steven G.; Macciardi, Fabio

2014-01-01

We investigated the genome-wide distribution of CNVs in the Alzheimer's disease (AD) Neuroimaging Initiative (ADNI) sample (146 with AD, 313 with Mild Cognitive Impairment (MCI), and 181 controls). Comparison of single CNVs between cases (MCI and AD) and controls shows overrepresentation of large heterozygous deletions in cases (p-value < 0.0001). The analysis of CNV-Regions identifies 44 copy number variable loci of heterozygous deletions, with more CNV-Regions among affected than controls (p = 0.005). Seven of the 44 CNV-Regions are nominally significant for association with cognitive impairment. We validated and confirmed our main findings with genome re-sequencing of selected patients and controls. The functional pathway analysis of the genes putatively affected by deletions of CNV-Regions reveals enrichment of genes implicated in axonal guidance, cell–cell adhesion, neuronal morphogenesis and differentiation. Our findings support the role of CNVs in AD, and suggest an association between large deletions and the development of cognitive impairment PMID:23583670

The Case for Intelligent Propulsion Control for Fast Engine Response

NASA Technical Reports Server (NTRS)

Litt, Jonathan S.; Frederick, Dean K.; Guo, Ten-Huei

2009-01-01

Damaged aircraft have occasionally had to rely solely on thrust to maneuver as a consequence of losing hydraulic power needed to operate flight control surfaces. The lack of successful landings in these cases inspired research into more effective methods of utilizing propulsion-only control. That research demonstrated that one of the major contributors to the difficulty in landing is the slow response of the engines as compared to using traditional flight control. To address this, research is being conducted into ways of making the engine more responsive under emergency conditions. This can be achieved by relaxing controller limits, adjusting schedules, and/or redesigning the regulators to increase bandwidth. Any of these methods can enable faster response at the potential expense of engine life and increased likelihood of stall. However, an example sensitivity analysis revealed a complex interaction of the limits and the difficulty in predicting the way to achieve the fastest response. The sensitivity analysis was performed on a realistic engine model, and demonstrated that significantly faster engine response can be achieved compared to standard Bill of Material control. However, the example indicates the need for an intelligent approach to controller limit adjustment in order for the potential to be fulfilled.

Malaria control and prevention towards elimination: data from an eleven-year surveillance in Shandong Province, China.

PubMed

Kong, Xiangli; Liu, Xin; Tu, Hong; Xu, Yan; Niu, Jianbing; Wang, Yongbin; Zhao, Changlei; Kou, Jingxuan; Feng, Jun

2017-01-31

Shandong Province experienced a declining malaria trend of local-acquired transmission, but the increasing imported malaria remains a challenge. Therefore, understanding the epidemiological characteristics of malaria and the control and elimination strategy and interventions is needed for better planning to achieve the overall elimination goal in Shandong Province. A retrospective study was conducted and all individual cases from a web-based reporting system were reviewed and analysed to explore malaria-endemic characteristics in Shandong from 2005 to 2015. Annual malaria incidence reported in 2005-2015 were geo-coded and matched to the county-level. Spatial cluster analysis was performed to evaluate any identified spatial disease clusters for statistical significance. The space-time cluster was detected with high rates through the retrospective space-time analysis scanning using the discrete Poisson model. The overall malaria incidence decreased to a low level during 2005-2015. In total, 1564 confirmed malaria cases were reported, 27.1% of which (n = 424) were indigenous cases. Most of the indigenous case (n = 339, 80.0%) occurred from June to October. However, the number and scale of imported cases have been increased but no significant difference was observed during months. Shandong is endemic for both Plasmodium vivax (n = 730) and Plasmodium falciparum (n = 674). The disease is mainly distributed in Southern (n = 710) and Eastern region (n = 424) of Shandong, such as Jinning (n = 214 [13.7%]), Weihai (n = 151 [9.7%]), and Yantai (n = 107 [6.8%]). Furthermore, the spatial cluster analysis of malaria cases from 2005 to 2015 indicated that the diseased was not randomly distributed. For indigenous cases, a total of 15 and 2 high-risk counties were determined from 2005 to 2009 (control phase) and from 2010 to 2015 (elimination phase), respectively. For imported cases, a total of 26 and 29 high-risk counties were determined from 2005 to 2009 (control phase) and from 2010 to 2015 (elimination phase), respectively. The method of spatial scan statistics identified different 13 significant spatial clusters between 2005 and 2015. The space-time clustering analysis determined that the most likely cluster included 14 and 19 counties for indigenous and imported, respectively. In order to cope with the requirements of malaria elimination phase, the surveillance system should be strengthened particularity on the frequent migration regions as well as the effective multisectoral cooperation and coordination mechanisms. Specific response packages should be tailored among different types of cities and capacity building should also be improved mainly focus on the emergence response and case management. Fund guarantees for scientific research should be maintained both during the elimination and post-elimination phase to consolidate the achievements of malaria elimination.

Plasma cytokine levels and risk of HIV type 1 (HIV-1) transmission and acquisition: a nested case-control study among HIV-1-serodiscordant couples.

PubMed

Kahle, Erin M; Bolton, Michael; Hughes, James P; Donnell, Deborah; Celum, Connie; Lingappa, Jairam R; Ronald, Allan; Cohen, Craig R; de Bruyn, Guy; Fong, Youyi; Katabira, Elly; McElrath, M Juliana; Baeten, Jared M

2015-05-01

A heightened proinflammatory state has been hypothesized to enhance human immunodeficiency virus type 1 (HIV-1) transmission - both susceptibility of HIV-1-exposed persons and infectiousness of HIV-1-infected persons. Using prospective data from heterosexual African couples with HIV-1 serodiscordance, we conducted a nested case-control analysis to assess the relationship between cytokine concentrations and the risk of HIV-1 acquisition. Case couples (n = 120) were initially serodiscordant couples in which HIV-1 was transmitted to the seronegative partner during the study; control couples (n = 321) were serodiscordant couples in which HIV-1 was not transmitted to the seronegative partner. Differences in a panel of 30 cytokines were measured using plasma specimens from both HIV-1-susceptible and HIV-1-infected partners. Plasma was collected before seroconversion for cases. For both HIV-1-infected and HIV-1-susceptible partners, cases and controls had significantly different mean responses in cytokine panels (P < .001, by the Hotelling T(2) test), suggesting a broadly different pattern of immune activation for couples in which HIV-1 was transmitted, compared with couples without transmission. Individually, log10 mean concentrations of interleukin 10 (IL-10) and CXCL10 were significantly higher for both HIV-1-susceptible and HIV-1-infected case partners, compared with HIV-1-susceptible and HIV-1-infected control partners (P < .01 for all comparisons). In multivariate analysis, HIV-1 transmission was significantly associated with elevated CXCL10 concentrations in HIV-1-susceptible partners (P = .001) and with elevated IL-10 concentrations in HIV-1-infected partners (P = .02). Immune activation, as measured by levels of cytokine markers, particularly elevated levels of IL-10 and CXCL1, are associated with increased HIV-1 susceptibility and infectiousness. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Morphological Features in Children with Autism Spectrum Disorders: A Matched Case-Control Study

ERIC Educational Resources Information Center

Ozgen, Heval; Hellemann, Gerhard S.; Stellato, Rebecca K.; Lahuis, Bertine; van Daalen, Emma; Staal, Wouter G.; Rozendal, Marije; Hennekam, Raoul C.; Beemer, Frits A.; van Engeland, Herman

2011-01-01

This study was designed to examine morphological features in a large group of children with autism spectrum disorder versus normal controls. Amongst 421 patients and 1,007 controls, 224 matched pairs were created. Prevalence rates and odds ratios were analyzed by conditional regression analysis, McNemar test or paired t-test matched pairs.…

Collective Actors and Corporate Targets in Tobacco Control: A Cross-National Comparison

ERIC Educational Resources Information Center

Nathanson, Constance A.

2005-01-01

Cross-national comparative analysis of tobacco control strategies can alert health advocates to how opportunities for public health action, types of action, and probabilities for success are shaped by political systems and cultures. This article is based on case studies of tobacco control in the United States, Canada, Britain, and France. Two…

Impact of maternal education, employment and family size on nutritional status of children.

PubMed

Iftikhar, Aisha; Bari, Attia; Bano, Iqbal; Masood, Qaisar

2017-01-01

To determine the impact of maternal education, employment, and family size on nutritional status of children. It was case control study conducted at OPD of children Hospital Lahore, from September 2015 to April 2017. Total 340 children (170 cases and 170 controls) with age range of six months to five years along with their mothers were included. Anthropometric measurements were plotted against WHO growth Charts. 170 wasted (<-2 SD) were matched with 170 controls (≥ -2 SD). Maternal education, employment and family size were compared between the cases and control. Confounding variables noted and dichotomized. Univariate analysis was carried out for factors under consideration i.e.; Maternal Education, employment and family size to study the association of each factor. Logistic regression analysis was applied to study the independent association. Maternal education had significant association with growth parameters; OR of 1.32 with confidence interval of (CI= 1.1 to 1.623). Employment status of mothers had OR of 1.132 with insignificant confidence interval of (CI=0.725 to 1.768). Family size had OR of one with insignificant confidence interval (CI=0.8 -1.21). Association remained same after applying bivariate logistic regression analysis. Maternal education has definite and significant effect on nutritional status of children. This is the key factor to be addressed for prevention or improvement of childhood malnutrition. For this it is imperative to launch sustainable programs at national and regional level to uplift women educational status to combat this ever increasing burden of malnutrition.

[PASS neurocognitive dysfunction in attention deficit].

PubMed

Pérez-Alvarez, F; Timoneda-Gallart, C

Attention deficit disorder shows both cognitive and behavioral patterns. To determine a particular PASS (planning, attention, successive and simultaneous) pattern in order to early diagnosis and remediation according to PASS theory. 80 patients were selected from the neuropediatric attendance, aged 6 to 12 years old, 55 boys and 25 girls. Inclusion criteria were inattention (80 cases) and inattention with hyperactive symptoms (40 cases) according to the Diagnostic and Statistical Manual (DSM-IV). Exclusion criteria were the criteria of phonologic awareness previously reported, considered useful to diagnose dyslexia. A control group of 300 individuals, aged 5 to 12 years old, was used, criteria above mentioned being controlled. DN:CAS (Das-Naglieri Cognitive Assessment System) battery, translated to native language, was given to assess PASS cognitive processes. Results were analyzed with cluster analysis and t-Student test. Statistical factor analysis of the control group had previously identified the four PASS processes: planning, attention, successive and simultaneous. The dendrogram of the cluster analysis discriminated three categories of attention deficit disorder: 1. The most frequent, with planning deficit; 2. Without planning deficit but with deficit in other processes, and 3. Just only a few cases, without cognitive processing deficit. Cognitive deficiency in terms of means of scores was statistically significant when compared to control group (p = 0.001). According to PASS pattern, planning deficiency is a relevant factor. Neurological planning is not exactly the same than neurological executive function. The behavioral pattern is mainly linked to planning deficiency, but also to other PASS processing deficits and even to no processing deficit.

Replication and meta-analysis of TMEM132D gene variants in panic disorder

PubMed Central

Erhardt, A; Akula, N; Schumacher, J; Czamara, D; Karbalai, N; Müller-Myhsok, B; Mors, O; Borglum, A; Kristensen, A S; Woldbye, D P D; Koefoed, P; Eriksson, E; Maron, E; Metspalu, A; Nurnberger, J; Philibert, R A; Kennedy, J; Domschke, K; Reif, A; Deckert, J; Otowa, T; Kawamura, Y; Kaiya, H; Okazaki, Y; Tanii, H; Tokunaga, K; Sasaki, T; Ioannidis, J P A; McMahon, F J; Binder, E B

2012-01-01

A recent genome-wide association study in patients with panic disorder (PD) identified a risk haplotype consisting of two single-nucleotide polymorphisms (SNPs) (rs7309727 and rs11060369) located in intron 3 of TMEM132D to be associated with PD in three independent samples. Now we report a subsequent confirmation study using five additional PD case–control samples (n=1670 cases and n=2266 controls) assembled as part of the Panic Disorder International Consortium (PanIC) study for a total of 2678 cases and 3262 controls in the analysis. In the new independent samples of European ancestry (EA), the association of rs7309727 and the risk haplotype rs7309727–rs11060369 was, indeed, replicated, with the strongest signal coming from patients with primary PD, that is, patients without major psychiatric comorbidities (n=1038 cases and n=2411 controls). This finding was paralleled by the results of the meta-analysis across all samples, in which the risk haplotype and rs7309727 reached P-levels of P=1.4e−8 and P=1.1e−8, respectively, when restricting the samples to individuals of EA with primary PD. In the Japanese sample no associations with PD could be found. The present results support the initial finding that TMEM132D gene contributes to genetic susceptibility for PD in individuals of EA. Our results also indicate that patient ascertainment and genetic background could be important sources of heterogeneity modifying this association signal in different populations. PMID:22948381

Occupational brain cancer risks in Umbria (Italy), with a particular focus on steel foundry workers.

PubMed

Oddone, Enrico; Scaburri, Alessandra; Bai, Edoardo; Modonesi, Carlo; Stracci, Fabrizio; Marchionna, Giuliano; Crosignani, Paolo; Imbriani, Marcello

2014-01-01

As a part of the Occupational Cancer Monitoring (OCCAM) project, a routine analysis based on Umbria region cancer registry (RTUP) database in 2002-2008 was performed. Among other results, the incidental finding of brain cancer increased risk in steel foundry workers in Terni province (Italy), lead us to deepen the analysis, focusing on this specific industrial sector. A monitoring study, based on Umbria Regional Cancer Registry data, was recently carried out. Brain cancer cases and controls identified within this preliminary study were selected. Therefore, we considered all incident cases (in Umbria region 2002-2008) of brain cancer occurred among workers occupied for at least one year in private companies since 1974 and controls randomly sampled from the same population. Afterwards, taking in to account results from steel foundry in Terni province, we further deepened our analysis, focusing on this productive sector. Odds ratios (ORs) and corresponding 90% confidence intervals (CIs) were calculated using multiple logistic regression models, adjusted by age at diagnosis or sampling, sex and province of residence, when appropriate. Statistical analyses were carried out on 14913 subjects, 56 cases and 14857 controls. Significantly increased ORs were observed for garment, mechanical manufacturing and chemical industries. Moreover, the risk estimates were strongly correlated with exposures in iron and steel foundries and a cluster of 14 cases in the same foundry in Terni was observed (OR 9.59, 90% CI 2.76-33.34). Results of this explorative study showed increased ORs of brain cancer in some productive branches, involving possible exposures to chemical compounds and/or solvents. Moreover, our results pointed out a significantly increased risk in Terni foundry workers, determining an interesting brain cancer cluster (14 cases). Further studies on this industrial sector are needed with improved definitions of tasks and exposures.

[A case-control study on the risk factors of work-related acute pesticide poisoning among farmers from Jiangsu province].

PubMed

Tu, Zhi-bin; Cui, Meng-jing; Yao, Hong-yan; Hu, Guo-qing; Xiang, Hui-yun; Stallones, Lorann; Zhang, Xu-jun

2012-04-01

To explore the risk factors on cases regarding work-related acute pesticide poisoning among farmers of Jiangsu province. A population-based, 1:2 matched case-control study was carried out, with 121 patients as case-group paired by 242 persons with same gender, district and age less then difference of 3 years, as controls. Cases were the ones who had suffered from work-related acute pesticide poisoning. A unified questionnaire was used. Data base was established by EpiData 3.1, and SPSS 16.0 was used for both data single factor and multi-conditional logistics regression analysis. Results from the single factor logistic regression analysis showed that the related risk factors were: lack of safety guidance, lack of readable labels before praying pesticides, no regression during application, using hand to wipe sweat, using leaking knapsack, body contaminated during application and continuing to work when feeling ill after the contact of pesticides. Results from multi-conditional logistic regression analysis indicated that the lack of safety guidance (OR=2.25, 95%CI: 1.35-3.74), no readable labels before praying pesticides (OR=1.95, 95%CI: 1.19-3.18), wiping the sweat by hand during application (OR=1.97, 95%CI: 1.20-3.24) and using leaking knapsack during application (OR=1.82, 95%CI:1.10-3.01) were risk factors for the occurrence of work-related acute pesticide poisoning. The lack of safety guidance, no readable labels before praying pesticides, wiping the sweat by hand or using leaking knapsack during application were correlated to the occurrence of work-related acute pesticide poisoning.

Evaluation of the efficiency and reliability of software generated by code generators

NASA Technical Reports Server (NTRS)

Schreur, Barbara

1994-01-01

There are numerous studies which show that CASE Tools greatly facilitate software development. As a result of these advantages, an increasing amount of software development is done with CASE Tools. As more software engineers become proficient with these tools, their experience and feedback lead to further development with the tools themselves. What has not been widely studied, however, is the reliability and efficiency of the actual code produced by the CASE Tools. This investigation considered these matters. Three segments of code generated by MATRIXx, one of many commercially available CASE Tools, were chosen for analysis: ETOFLIGHT, a portion of the Earth to Orbit Flight software, and ECLSS and PFMC, modules for Environmental Control and Life Support System and Pump Fan Motor Control, respectively.

No direct correlation between rotavirus diarrhea and breast feeding: A meta-analysis.

PubMed

Shen, Jian; Zhang, Bi-Meng; Zhu, Sheng-Guo; Chen, Jian-Jie

2018-04-01

Some studies indicated that children with exclusive breast feeding had a reduction in the prevalence of rotavirus diarrhea, while some others held the opposite views. In this study, we aimed to systematically find the associations between rotavirus diarrhea and breast feeding. A literature search up to June 2016 in electronic literature databases, including PubMed and Embase, was performed. The Newcastle-Ottawa Scale was used to conduct the quality assessment of all the selected studies. Statistical analyses were performed using the R package version 3.12 (R Foundation for Statistical Computing, Beijing1, China, meta package), and odds ratio (OR) and 95% confidence interval (CI) were used to assess the strength of the association. The heterogeneity was assessed by Cochran's Q-statistic and I 2 test, and the sensitivity analysis was performed by trimming one study at a time. A total of 17 articles, which included 10,841 participants, were investigated in the present meta-analysis. There was no significant difference between the case group and control group (OR, 0.59 95% CI 0.33-1.07) in the meta-analysis of exclusive breast feeding, and no significant difference was found between the case group and the control group (OR, 0.86; 95% CI 0.63-1.16) in the meta-analysis of breast feeding. No significant difference was found between the case group and control group (OR, 0.78 95% CI 0.59-1.04) for all quantitative data. There may be no direct correlation between rotavirus diarrhea and breast feeding. Copyright © 2017. Published by Elsevier B.V.

Modeling and projection of dengue fever cases in Guangzhou based on variation of weather factors.

PubMed

Li, Chenlu; Wang, Xiaofeng; Wu, Xiaoxu; Liu, Jianing; Ji, Duoying; Du, Juan

2017-12-15

Dengue fever is one of the most serious vector-borne infectious diseases, especially in Guangzhou, China. Dengue viruses and their vectors Aedes albopictus are sensitive to climate change primarily in relation to weather factors. Previous research has mainly focused on identifying the relationship between climate factors and dengue cases, or developing dengue case models with some non-climate factors. However, there has been little research addressing the modeling and projection of dengue cases only from the perspective of climate change. This study considered this topic using long time series data (1998-2014). First, sensitive weather factors were identified through meta-analysis that included literature review screening, lagged analysis, and collinear analysis. Then, key factors that included monthly average temperature at a lag of two months, and monthly average relative humidity and monthly average precipitation at lags of three months were determined. Second, time series Poisson analysis was used with the generalized additive model approach to develop a dengue model based on key weather factors for January 1998 to December 2012. Data from January 2013 to July 2014 were used to validate that the model was reliable and reasonable. Finally, future weather data (January 2020 to December 2070) were input into the model to project the occurrence of dengue cases under different climate scenarios (RCP 2.6 and RCP 8.5). Longer time series analysis and scientifically selected weather variables were used to develop a dengue model to ensure reliability. The projections suggested that seasonal disease control (especially in summer and fall) and mitigation of greenhouse gas emissions could help reduce the incidence of dengue fever. The results of this study hope to provide a scientifically theoretical basis for the prevention and control of dengue fever in Guangzhou. Copyright © 2017 Elsevier B.V. All rights reserved.

Lung function in type 2 diabetes: the Normative Aging Study.

PubMed

Litonjua, Augusto A; Lazarus, Ross; Sparrow, David; Demolles, Debbie; Weiss, Scott T

2005-12-01

Cross-sectional studies have noted that subjects with diabetes have lower lung function than non-diabetic subjects. We conducted this analysis to determine whether diabetic subjects have different rates of lung function change compared with non-diabetic subjects. We conducted a nested case-control analysis in 352 men who developed diabetes and 352 non-diabetic subjects in a longitudinal observational study of aging in men. We assessed lung function among cases and controls at three time points: Time0, prior to meeting the definition of diabetes; Time1, the point when the definition of diabetes was met; and Time2, the most recent follow-up exam. Cases had lower forced expiratory volume in 1s (FEV1) and forced vital capacity (FVC) at all time points, even with adjustment for age, height, weight, and smoking. In multiple linear regression models adjusting for relevant covariates, there were no differences in rates of FEV1 or FVC change over time between cases and controls. Men who are predisposed to develop diabetes have decreased lung function many years prior to the diagnosis, compared with men who do not develop diabetes. This decrement in lung function remains after the development of diabetes. We postulate that mechanisms involved in the insulin resistant state contribute to the diminished lung function observed in our subjects.

A genome-wide assessment of rare copy number variants in colorectal cancer.

PubMed

Li, Zhenli; Yu, Dan; Gan, Meifu; Shan, Qiaonan; Yin, Xiaoyang; Tang, Shunli; Zhang, Shuai; Shi, Yongyong; Zhu, Yimin; Lai, Maode; Zhang, Dandan

2015-09-22

Colorectal cancer (CRC) is a complex disease with an estimated heritability of approximately 35%. However, known CRC-related common single nucleotide polymorphisms (SNPs) can only explain ~0.65% of the heritability. This "missing heritability" may be explained partially by rare copy number variants (CNVs). In this study, we performed a genome-wide scan using Illumina Human-Omni Express BeadChip, 694 sporadic CRC cases and 1641 controls were eventually included in our analysis after quality control. The global burden analysis revealed a 1.53-fold excess of rare CNVs in CRC cases compared with controls (P < 1 × 10(-6)), and the difference being more pronounced for genic rare CNVs and CNVs overlapped with coding regions (1.65-fold and 1.84-fold, respectively, both P < 1 × 10(-6)). Interestingly, both the cases in the lowest and middle tertile of age carried a higher burden of rare CNVs comparing to the highest tertile. Furthermore, 639 CNV-disrupted genes exclusive to CRC cases were found to be significantly enriched in gene ontology (GO) terms concerning nucleosome assembly and olfactory receptor activity. Our study was the first to evaluate the burden of rare CNVs in sporadic CRC and suggested that rare CNVs contributed to the missing heritability of CRC.

Statin use and risk of cholecystectomy - A case-control analysis using Swiss claims data.

PubMed

Biétry, Fabienne A; Reich, Oliver; Schwenkglenks, Matthias; Meier, Christoph R

2016-12-01

Using claims data from the Helsana Group, a large Swiss health insurance provider, we examined the association between statin use and the risk of cholecystectomy in a case-control analysis. We identified 2,200 cholecystectomy cases between 2013 and 2014 and matched 4 controls to each case on age, sex, index date and canton. We categorized statin users into current or past users (last prescription ≤ 180 or > 180 days before the index date, respectively) and classified medication use by duration based on number of prescriptions before the index date. We applied conditional logistic regression analyses to calculate odds ratios (ORs) with 95% confidence intervals (CIs) and adjusted the analyses for history of cardiovascular diseases and for use of estrogens, fibrates and other lipid-lowering agents. The adjusted OR (aOR) for cholecystectomy was 0.85 (95% CI: 0.74, 0.99) for current statin users compared to non-users. Long-term current statin use (5-19 prescriptions) was associated with a reduced OR (aOR 0.77, 95% CI: 0.65, 0.92). However, neither short-term current use nor past statin use affected the risk of cholecystectomy. The study supports the previously raised hypothesis that long-term statin use reduces the risk of cholecystectomy.

Systematic Review and Meta-Analysis of Association of Smokeless Tobacco and of Betel Quid without Tobacco with Incidence of Oral Cancer in South Asia and the Pacific

PubMed Central

Gupta, Bhawna; Johnson, Newell W.

2014-01-01

Aim This systematic review and meta-analysis aimed to critically appraised data from comparable studies leading to quantitative assessment of any independent association between use of oral smokeless tobacco in any form, of betel quid without tobacco and of areca nut with incidence of oral cancer in South Asia and the Pacific. Methods Studies (case control and/or cohort) were identified by searching Pub Med, CINAHL and Cochrane databases through June 2013 using the keywords oral cancer: chewing tobacco; smokeless tobacco; betel quid; betel quid without tobacco; areca nut; Asia, the Pacific and the reference lists of retrieved articles. A random effects model was used to compute adjusted summary ORRE for the main effect of these habits along with their corresponding 95% confidence intervals. To quantify the impact of between-study heterogeneity on adjusted main-effect summary ORRE, Higgins' H and I2 statistics along with their 95% uncertainty intervals were used. Funnel plots and Egger's test were used to evaluate publication bias. Results Meta-analysis of fifteen case–control studies (4,553 cases; 8,632 controls) and four cohort studies (15,342) which met our inclusion criteria showed that chewing tobacco is significantly and independently associated with an increased risk of squamous-cell carcinoma of the oral cavity (adjusted main-effect summary for case- control studies ORRE = 7.46; 95% CI = 5.86–9.50, P<0.001), (adjusted main-effect summary for cohort studies RR = 5.48; 95% CI = 2.56–11.71, P<0.001). Furthermore, meta-analysis of fifteen case control studies (4,648 cases; 7,847 controls) has shown betel quid without tobacco to have an independent positive association with oral cancer, with OR = 2.82 (95% CI = 2.35–3.40, P<0.001). This is presumably due to the carcinogenicity of areca nut. There was no significant publication bias. Conclusion There is convincing evidence that smokeless (aka chewing) tobacco, often used as a component of betel quid, and betel quid without tobacco, are both strong and independent risk factors for oral cancer in these populations. However, studies with better separation of the types of tobacco and the ways in which it is used, and studies with sufficient power to quantify dose-response relationships are still needed. PMID:25411778

Consanguinity and family clustering of male factor infertility in Lebanon.

PubMed

Inhorn, Marcia C; Kobeissi, Loulou; Nassar, Zaher; Lakkis, Da'ad; Fakih, Michael H

2009-04-01

To investigate the influence of consanguineous marriage on male factor infertility in Lebanon, where rates of consanguineous marriage remain high (29.6% among Muslims, 16.5% among Christians). Clinic-based, case-control study, using reproductive history, risk factor interview, and laboratory-based semen analysis. Two IVF clinics in Beirut, Lebanon, during an 8-month period (January-August 2003). One hundred twenty infertile male patients and 100 fertile male controls, distinguished by semen analysis and reproductive history. None. Standard clinical semen analysis. The rates of consanguineous marriage were relatively high among the study sample. Patients (46%) were more likely than controls (37%) to report first-degree (parental) and second-degree (grandparental) consanguinity. The study demonstrated a clear pattern of family clustering of male factor infertility, with patients significantly more likely than controls to report infertility among close male relatives (odds ratio = 2.58). Men with azoospermia and severe oligospermia showed high rates of both consanguinity (50%) and family clustering (41%). Consanguineous marriage is a socially supported institution throughout the Muslim world, yet its relationship to infertility is poorly understood. This study demonstrated a significant association between consanguinity and family clustering of male factor infertility cases, suggesting a strong genetic component.

Haloacetic acids in drinking water and risk for stillbirth

PubMed Central

King, W; Dodds, L; Allen, A; Armson, B; Fell, D; Nimrod, C

2005-01-01

Aims: To investigate the effects of haloacetic acid (HAA) compounds in drinking water on stillbirth risk. Methods: A population based case-control study was conducted in Nova Scotia and Eastern Ontario, Canada. Estimates of daily exposure to total and specific HAAs were based on household water samples and questionnaire information on water consumption at home and work. Results: The analysis included 112 stillbirth cases and 398 live birth controls. In analysis without adjustment for total THM exposure, a relative risk greater than 2 was observed for an intermediate exposure category for total HAA and dichloroacetic acid measures. After adjustment for total THM exposure, the risk estimates for intermediate exposure categories were diminished, the relative risk associated with the highest category was in the direction of a protective effect, and all confidence intervals included the null value. Conclusions: No association was observed between HAA exposures and stillbirth risk after controlling for THM exposures. PMID:15657195

Association of OPRD1 polymorphisms with heroin dependence in a large case-control series.

PubMed

Nelson, Elliot C; Lynskey, Michael T; Heath, Andrew C; Wray, Naomi; Agrawal, Arpana; Shand, Fiona L; Henders, Anjali K; Wallace, Leanne; Todorov, Alexandre A; Schrage, Andrew J; Madden, Pamela A F; Degenhardt, Louisa; Martin, Nicholas G; Montgomery, Grant W

2014-01-01

Genes encoding the opioid receptors (OPRM1, OPRD1 and OPRK1) are obvious candidates for involvement in risk for heroin dependence. Prior association studies commonly had samples of modest size, included limited single nucleotide polymorphism (SNP) coverage of these genes and yielded inconsistent results. Participants for the current investigation included 1459 heroin-dependent cases ascertained from maintenance clinics in New South Wales, Australia, 1495 unrelated individuals selected from an Australian sample of twins and siblings as not meeting DSM-IV criteria for lifetime alcohol or illicit drug dependence (non-dependent controls) and 531 controls ascertained from economically disadvantaged neighborhoods in proximity to the maintenance clinics. A total of 136 OPRM1, OPRD1 and OPRK1 SNPs were genotyped in this sample. After controlling for admixture with principal components analysis, our comparison of cases to non-dependent controls found four OPRD1 SNPs in fairly high linkage disequilibrium for which adjusted P values remained significant (e.g. rs2236857; OR 1.25; P=2.95×10(-4) ) replicating a previously reported association. A post hoc analysis revealed that the two SNP (rs2236857 and rs581111) GA haplotype in OPRD1 is associated with greater risk (OR 1.68; P=1.41×10(-5) ). No OPRM1 or OPRK1 SNPs reached more than nominal significance. Comparisons of cases to neighborhood controls reached only nominal significance. Our results replicate a prior report providing strong evidence implicating OPRD1 SNPs and, in particular, the two SNP (rs2236857 and rs581111) GA haplotype in liability for heroin dependence. Support was not found for similar association involving either OPRM1 or OPRK1 SNPs. © 2012 The Authors, Addiction Biology © 2012 Society for the Study of Addiction.

Leptospira Exposure and Gardeners: A Case-Control Seroprevalence Study

PubMed Central

Alvarado-Esquivel, Cosme; Hernandez-Tinoco, Jesus; Sanchez-Anguiano, Luis Francisco; Ramos-Nevarez, Agar; Cerrillo-Soto, Sandra Margarita; Guido-Arreola, Carlos Alberto

2016-01-01

Background Leptospira can be found in soil. However, it is unclear whether occupational exposure to soil may represent a risk for Leptospira infection in humans. Therefore, we sought to determine the association of Leptospira IgG seroprevalence with the occupation of gardener, and to determine the epidemiological characteristics of gardeners associated with Leptospira exposure. Methods We performed a case-control study in 168 gardeners and 168 age- and gender-matched control subjects without gardening occupation in Durango City, Mexico. The seroprevalence of anti-Leptospira IgG antibodies in cases and controls was determined using an enzyme immunoassay. Bivariate and multivariate analyses were used to assess the association of Leptospira exposure and the characteristics of the gardeners. Results Anti-Leptospira IgG antibodies were found in 10 (6%) of 168 gardeners and in 15 (8.9%) of 168 control subjects (odds ratio (OR): 0.64; 95% confidence interval (CI): 0.28 - 1.48; P = 0.40). Multivariate analysis showed that Leptospira seropositivity was positively associated with female gender (OR: 5.82; 95% CI: 1.11 - 30.46; P = 0.03), and negatively associated with eating while working (OR: 0.21; 95% CI: 0.05 - 0.87; P = 0.03). In addition, multivariate analysis showed that high anti-Leptospira levels were associated with consumption of boar meat (OR: 28.00; 95% CI: 1.20 - 648.80; P = 0.03). Conclusions This is the first case-control study of Leptospira exposure in gardeners. Results do not support an association of Leptospira exposure with the occupation of gardener. However, further studies to confirm the lack of this association are needed. The potential role of consumption of boar meat in Leptospira infection deserves further investigation. PMID:26668679

Body Mass Index and Breast Cancer Risk among Thai Premenopausal Women: a Case-Control Study

PubMed Central

Chaveepojnkamjorn, Wisit; Thotong, Rungsinoppadol; Sativipawee, Pratana; Pitikultang, Supachai

2017-01-01

Background: Breast cancer (BC) is the leading malignancy in women with high incidence and mortality worldwide. Obesity is one of several established risk factors for chronic diseases including cancer. The objective of this research was to determine the association of body mass index (BMI) with BC among Thai premenopausal women (TPW). Materials and Methods: A case-control study was conducted among TPW attending the National Cancer Institute in Bangkok, with 257 cases and 257 controls in 2013-2014. Cases and controls were matched by age (± 5 years), residential area and duration of attending. Data were collected with a questionnaire comprising 2 parts: part 1 socio-demographic characteristics, and part 2 health risk behavior and reproductive factors and BMI. The obtained data were analyzed using descriptive and analytic statistics with a computerized statistical package. Results: The study participants were mainly 40-44 years old (60 %) with an average age of 39 years. The major type of BC was the invasive ductal carcinoma (91.8%). On univariate analysis, risk factors for BC among the TPW were family history of BC, history of benign breast tumors, younger age at menarche, parity, miscarriage, contraceptive use, passive smoking, multivitamin use, and BMI (p<0.05). Multivariable conditional logistic regression analysis, controlling for possible confounding factors, revealed that a BMI 25-29.9 and ≥ 30 kg/m2 increased the risk of BC by a factor of 2.09 and 2.37 times, respectively (OR=2.09, 95%CI =1.09-3.97; OR=2.37, 95%CI =1.24-10.06). Conclusions: A surveillance system of obesity should be conducted in cooperation with information regarding physical activities and weight control among TPW as an essential measure to reduce BC risk. PMID:29172285

Alcohol Intake and Risk of Thyroid Cancer: A Meta-Analysis of Observational Studies

PubMed Central

Hong, Seung-Hee; Myung, Seung-Kwon; Kim, Hyeon Suk

2017-01-01

Purpose The purpose of this study was to assess whether alcohol intake is associated with the risk of thyroid cancer by a meta-analysis of observational studies. Materials and Methods We searched PubMed and EMBASE in June of 2015 to locate eligible studies. We included observational studies such as cross-sectional studies, case-control studies, and cohort studies reporting odd ratios (ORs) or relative risk (RRs) with 95% confidence intervals (CIs). Results We included 33 observational studies with two cross-sectional studies, 20 case-controls studies, and 11 cohort studies, which involved a total of 7,725 thyroid cancer patients and 3,113,679 participants without thyroid cancer in the final analysis. In the fixed-effect model meta-analysis of all 33 studies, we found that alcohol intake was consistently associated with a decreased risk of thyroid cancer (OR or RR, 0.74; 95% CI, 0.67 to 0.83; I2=38.6%). In the subgroup meta-analysis by type of study, alcohol intake also decreased the risk of thyroid cancer in both case-control studies (OR, 0.77; 95% CI, 0.65 to 0.92; I2=29.5%; n=20) and cohort studies (RR, 0.70; 95% CI, 0.60 to 0.82; I2=0%; n=11). Moreover, subgroup meta-analyses by type of thyroid cancer, gender, amount of alcohol consumed, and methodological quality of study showed that alcohol intake was significantly associated with a decreased risk of thyroid cancer. Conclusion The current meta-analysis of observational studies found that, unlike most of other types of cancer, alcohol intake decreased the risk of thyroid cancer. PMID:27456949

Caffeine intake from coffee or tea and cognitive disorders: a meta-analysis of observational studies.

PubMed

Kim, Young-Seok; Kwak, Sang Mi; Myung, Seung-Kwon

2015-01-01

Observational epidemiological studies such as cross-sectional, case-control, and cohort studies have reported inconsistent findings regarding the association between caffeine intake from coffee or tea and the risk of cognitive disorders such as dementia, Alzheimer's disease, cognitive impairment, and cognitive decline. We searched PubMed and EMBASE in September 2014. Three evaluators independently extracted and reviewed articles, based on predetermined selection criteria. Out of 293 articles identified through the search and bibliographies of relevant articles, 20 epidemiological studies from 19 articles, which involved 31,479 participants (8,398 in six cross-sectional studies, 4,601 in five case-control studies, and 19,918 in nine cohort studies), were included in the final analysis. The pooled odds ratio (OR) or relative risk (RR) of caffeine intake from coffee or tea for cognitive disorders (dementia, Alzheimer's disease, cognitive impairment, and cognitive decline) was 0.82 (95% confidence interval [CI], 0.67-1.01, I² = 63.2%) in a random-effects meta-analysis. In the subgroup meta-analysis by caffeine sources, the summary OR or RR of coffee intake was 0.83 (95% CI, 0.70-0.98; I² = 44.8%). However, in the subgroup meta-analysis by study design, the summary estimates (RR or OR) of coffee intake for cognitive disorders were 0.70 (95% CI, 0.50-0.98; I² = 42.0%) for cross-sectional studies, 0.82 (95% CI, 0.55-1.24; I² = 33.4%) for case-control studies, and 0.90 (95% CI, 0.59-1.36; I² = 60.0%) for cohort studies. This meta-analysis found that caffeine intake from coffee or tea was not associated with the risk of cognitive disorders.

No effect of 2008/09 seasonal influenza vaccination on the risk of pandemic H1N1 2009 influenza infection in England.

PubMed

Pebody, Richard; Andrews, Nick; Waight, Pauline; Malkani, Rashmi; McCartney, Christine; Ellis, Joanna; Miller, Elizabeth

2011-03-21

This study reports effectiveness of trivalent influenza vaccine (TIV) against confirmed pandemic influenza infection in England using a retrospective test-negative case-control study. Cases and controls were frequency matched by age, swabbing-week and region. On univariable and multivariable analysis adjusted for underlying clinical risk factors, cases were no more or less likely than controls to be vaccinated with 2008-09 or 2007-08 season TIV. Adjusted vaccine effectiveness for the former was -6% (-43% to 22%). Vaccine effectiveness did not differ significantly by age-group or hospitalisation status. There was no evidence prior vaccination with TIV significantly altered subsequent risk of pandemic influenza H1N1 2009 infection. Copyright © 2011 Elsevier Ltd. All rights reserved.

Cutaneous sarcoidosis: A retrospective case series and a hospital-based case-control study in Taiwan.

PubMed

Liu, Kwei-Lan; Tsai, Wen-Chien; Lee, Chih-Hung

2017-10-01

Sarcoidosis is a systemic granulomatous disorder of unknown etiology often involving skin. Studies on cutaneous sarcoidosis and comorbidities are limited. This study is aimed to describe the clinical features of cutaneous sarcoidosis diagnosed in our hospital and to determine the relationships between cutaneous sarcoidosis and comorbidities.This retrospective study evaluates patients with cutaneous sarcoidosis in a tertiary center in Taiwan from 1996 to 2015. The records of 38 patients with cutaneous sarcoidosis were reviewed for clinical characteristics and evaluated by analysis of variance. A 1:4 case-control analysis was conducted with 152 age- and sex-matched controls who underwent biopsy for other benign skin tumors.The male to female ratio was 1:4.4. The average age at diagnosis was 51.7 years. Female patients were on average 13.9 years older than male patients. The correlation of age with gender was statistically significant (P = .037). The most common cutaneous lesions were plaques (47.4%) and confined to the face (71.1%). Of the 38 patients, 26.3% had diabetes mellitus. Age over 40 (P = .014) and female (P = .014) were associated with facial involvement. In the case-control study, a higher percentage of patients with cutaneous sarcoidosis than of control subjects had diabetes mellitus (P = .001), hearing loss (P = .031) and eye diseases (P = .047).The present study demonstrates a striking female predominance and high proportions of facial involvement. Diabetes mellitus, hearing loss, and eye diseases may be associated with Taiwanese patients with cutaneous sarcoidosis.

Connection between optimal control theory and adiabatic-passage techniques in quantum systems

NASA Astrophysics Data System (ADS)

Assémat, E.; Sugny, D.

2012-08-01

This work explores the relationship between optimal control theory and adiabatic passage techniques in quantum systems. The study is based on a geometric analysis of the Hamiltonian dynamics constructed from Pontryagin's maximum principle. In a three-level quantum system, we show that the stimulated Raman adiabatic passage technique can be associated to a peculiar Hamiltonian singularity. One deduces that the adiabatic pulse is solution of the optimal control problem only for a specific cost functional. This analysis is extended to the case of a four-level quantum system.

Specific features of colorectal cancer in patients with metabolic syndrome: a matched case-control analysis of 772 patients.

PubMed

Zarzavadjian Le Bian, Alban; Denet, Christine; Tabchouri, Nicolas; Donatelli, Gianfranco; Wind, Philippe; Louvet, Christophe; Bennamoun, Mostefa; Christidis, Christos; Perniceni, Thierry; Fuks, David; Gayet, Brice

2018-06-01

Although association between colorectal cancer (CRC) and metabolic syndrome (MetS) is established, specific features of CRC arising in patients presenting with MetS have not been clearly identified. All patients who underwent colectomy for CRC from January 2005 to December 2014 at Institut Mutualiste Montsouris were identified from a prospectively collected database and characteristics were compared in the entire population and in a 1:2 matched case-control analysis [variables on which matching was performed were CRC localization (right- or left-sided) and AJCC stage (0 to IV)]. Out of the 772 identified patients, 98 (12.7%) presented with MetS. Entire population analysis revealed that CRC associated with MetS was more frequent in men (71.4 vs. 47.8%, p < 0.001), more often right-sided (71.4 vs. 50.4%, p < 0.001) and presented with less synchronous liver metastasis (4.1 vs. 8.7%, p = 0.002). Case-control analysis confirmed the gender association (p < 0.001) and showed HNPCC (p < 0.001) and history family of CRC (p = 0.010) to be significantly more frequent in Non-MetS patients. CRC associated with MetS is more frequent in men, more often right-sided, and presents with fewer synchronous metastasis. Further investigations should be designed in order to confirm these results and to enhance our knowledge of carcinogenesis related to MetS.

A case-control analysis on the association between erectile dysfunction and sudden sensorineural hearing loss in Taiwan.

PubMed

Keller, Joseph J; Chen, Yi-Kuang; Lin, Herng-Ching

2012-05-01

Although the cause of sudden sensorineural hearing loss (SSNHL) is yet to be elucidated, many theories have been proposed regarding potentially contributory etiologies. One increasingly well-supported theory purports an underlying vascular pathomechanism. If this is the case, SSNHL may also associate with conditions comorbid with vascular diseases, such as erectile dysfunction (ED). However, no studies to date have investigated the association between ED and SSNHL. This study set out to estimate a putative association between ED and having been previously diagnosed with SSNHL using a population-based dataset with a case-control design. This study used administrative claim data from the Taiwan National Health Insurance program. We identified 4,504 patients with ED as the study group and randomly selected 22,520 patients as the comparison group. Conditional logistic regression was used to examine the association between ED and having previously received a diagnosis of SSNHL. The prevalence and risk of SSNHL between cases and controls were calculated. Of the sampled patients, 41 (0.15%) had been diagnosed with SSNHL before the index date; 22 (0.49% of the cases) were from the study group and 19 (0.08% of controls) were from the control group. Conditional logistic regression analysis revealed that after adjusting for the patient's monthly income, geographic location, hypertension, diabetes, hyperlipidemia, coronary heart disease, obesity, and alcohol abuse/alcohol dependence syndrome status, patients with ED were more likely than controls to have been diagnosed with SSNHL before the index date (odds ratio = 6.06, 95% confidence interval = 3.25-11.29). There was an association between ED and prior SSNHL. The results of this study add to the evidence supporting an underlying vascular pathomechanism regarding the development of SSNHL and highlight a need for clinicians dealing with SSNHL patients to be alert to the development of ED. © 2012 International Society for Sexual Medicine.

Control selection and confounding factors: A lesson from a Japanese case-control study to examine acellular pertussis vaccine effectiveness.

PubMed

Ohfuji, Satoko; Okada, Kenji; Nakano, Takashi; Ito, Hiroaki; Hara, Megumi; Kuroki, Haruo; Hirota, Yoshio

2017-08-24

When using a case-control study design to examine vaccine effectiveness, both the selection of control subjects and the consideration of potential confounders must be the important issues to ensure accurate results. In this report, we described our experience from a case-control study conducted to evaluate the effectiveness of acellular pertussis vaccine combined with diphtheria-tetanus toxoids (DTaP vaccine). Newly diagnosed pertussis cases and age- and sex-matched friend-controls were enrolled, and the history of DTaP vaccination was compared between groups. Logistic regression models were used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) of vaccination for development of pertussis. After adjustment for potential confounders, four doses of DTaP vaccination showed a lower OR for pediatrician-diagnosed pertussis (OR=0.11, 95% CI, 0.01-0.99). In addition, the decreasing OR of four doses vaccination was more pronounced for laboratory-confirmed pertussis (OR=0.07, 95%CI, 0.01-0.82). Besides, positive association with pertussis was observed in subjects with a history of steroid treatment (OR=5.67) and those with a recent contact with a lasting cough (OR=4.12). When using a case-control study to evaluate the effectiveness of vaccines, particularly those for uncommon infectious diseases such as pertussis, the use of friend-controls may be optimal due to the fact that they shared a similar experience for exposure to the pathogen as the cases. In addition, to assess vaccine effectiveness as accurately as possible, the effects of confounding should be adequately controlled with a matching or analysis technique. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Hip fracture risk in relation to vitamin D supplementation and serum 25-hydroxyvitamin D levels: a systematic review and meta-analysis of randomised controlled trials and observational studies

PubMed Central

2010-01-01

Background Vitamin D supplementation for fracture prevention is widespread despite conflicting interpretation of relevant randomised controlled trial (RCT) evidence. This study summarises quantitatively the current evidence from RCTs and observational studies regarding vitamin D, parathyroid hormone (PTH) and hip fracture risk. Methods We undertook separate meta-analyses of RCTs examining vitamin D supplementation and hip fracture, and observational studies of serum vitamin D status (25-hydroxyvitamin D (25(OH)D) level), PTH and hip fracture. Results from RCTs were combined using the reported hazard ratios/relative risks (RR). Results from case-control studies were combined using the ratio of 25(OH)D and PTH measurements of hip fracture cases compared with controls. Original published studies of vitamin D, PTH and hip fracture were identified through PubMed and Web of Science databases, searches of reference lists and forward citations of key papers. Results The seven eligible RCTs identified showed no significant difference in hip fracture risk in those randomised to cholecalciferol or ergocalciferol supplementation versus placebo/control (RR = 1.13[95%CI 0.98-1.29]; 801 cases), with no significant difference between trials of <800 IU/day and ≥800 IU/day. The 17 identified case-control studies found 33% lower serum 25(OH)D levels in cases compared to controls, based on 1903 cases. This difference was significantly greater in studies with population-based compared to hospital-based controls (χ21 (heterogeneity) = 51.02, p < 0.001) and significant heterogeneity was present overall (χ216 (heterogeneity) = 137.9, p < 0.001). Serum PTH levels in hip fracture cases did not differ significantly from controls, based on ten case-control studies with 905 cases (χ29 (heterogeneity) = 149.68, p < 0.001). Conclusions Neither higher nor lower dose vitamin D supplementation prevented hip fracture. Randomised and observational data on vitamin D and hip fracture appear to differ. The reason for this is unclear; one possible explanation is uncontrolled confounding in observational studies. Post-fracture PTH levels are unrelated to hip fracture risk. PMID:20540727

No association between the sigma receptor type 1 gene and schizophrenia: results of analysis and meta-analysis of case-control studies

PubMed Central

Uchida, Naohiko; Ujike, Hiroshi; Nakata, Kenji; Takaki, Manabu; Nomura, Akira; Katsu, Takeshi; Tanaka, Yuji; Imamura, Takaki; Sakai, Ayumu; Kuroda, Shigetoshi

2003-01-01

Background Several lines of evidence have supported possible roles of the sigma receptors in the etiology of schizophrenia and mechanisms of antipsychotic efficacy. An association study provided genetic evidence that the sigma receptor type 1 gene (SIGMAR1) was a possible susceptibility factor for schizophrenia, however, it was not replicated by a subsequent study. It is necessary to evaluate further the possibility that the SIGMAR1 gene is associated with susceptibility to schizophrenia. Methods A case-control association study between two polymorphisms of the SIGMAR1 gene, G-241T/C-240T and Gln2Pro, and schizophrenia in Japanese population, and meta-analysis including present and previous studies. Results There was no significant association of any allele or genotype of the polymorphisms with schizophrenia. Neither significant association was observed with hebephrenic or paranoid subtype of schizophrenia. Furthermore, a meta-analysis including the present and previous studies comprising 779 controls and 636 schizophrenics also revealed no significant association between the SIGMAR1 gene and schizophrenia. Conclusion In view of this evidence, it is likely that the SIGMAR1 gene does not confer susceptibility to schizophrenia. PMID:14567761

No association between the sigma receptor type 1 gene and schizophrenia: results of analysis and meta-analysis of case-control studies.

PubMed

Uchida, Naohiko; Ujike, Hiroshi; Nakata, Kenji; Takaki, Manabu; Nomura, Akira; Katsu, Takeshi; Tanaka, Yuji; Imamura, Takaki; Sakai, Ayumu; Kuroda, Shigetoshi

2003-10-21

Several lines of evidence have supported possible roles of the sigma receptors in the etiology of schizophrenia and mechanisms of antipsychotic efficacy. An association study provided genetic evidence that the sigma receptor type 1 gene (SIGMAR1) was a possible susceptibility factor for schizophrenia, however, it was not replicated by a subsequent study. It is necessary to evaluate further the possibility that the SIGMAR1 gene is associated with susceptibility to schizophrenia. A case-control association study between two polymorphisms of the SIGMAR1 gene, G-241T/C-240T and Gln2Pro, and schizophrenia in Japanese population, and meta-analysis including present and previous studies. There was no significant association of any allele or genotype of the polymorphisms with schizophrenia. Neither significant association was observed with hebephrenic or paranoid subtype of schizophrenia. Furthermore, a meta-analysis including the present and previous studies comprising 779 controls and 636 schizophrenics also revealed no significant association between the SIGMAR1 gene and schizophrenia. In view of this evidence, it is likely that the SIGMAR1 gene does not confer susceptibility to schizophrenia.

Role of mtDNA haplogroups in the prevalence of osteoarthritis in different geographic populations: a meta-analysis.

PubMed

Shen, Jin-Ming; Feng, Lei; Feng, Chun

2014-01-01

Osteoarthritis (OA) is the most common form of arthritis and has become an increasingly important public-health problem. However, the pathogenesis of OA is still unclear. In recent years, its correlation with mtDNA haplogroups attracts much attention. We aimed to perform a meta-analysis to investigate the association between mtDNA haplogroups and OA. Published English or Chinese literature from PubMed, Web of Science, SDOS, and CNKI was retrieved up until April 15, 2014. Case-control or cohort studies that detected the frequency of mtDNA haplogroups in OA patients and controls were included. The quality of the included studies was evaluated by the Newcastle-Ottawa Scale (NOS) assessment. A meta-analysis was conducted to calculate pooled odds ratio (OR) with 95% confidence interval (CI) through the random or fixed effect model, which was selected based on the between-study heterogeneity assessed by Q test and I2 test. Subgroup analysis was performed to explore the origin of heterogeneity. A total of 6 case-control studies (10590 cases and 7161 controls) with an average NOS score of 6.9 were involved. For the analysis between mtDNA haplogroup J and OA, random model was selected due to high heterogeneity. No significant association was found initially (OR = 0.73, 95%CI: 0.52-1.03), however, once any study from UK population was removed the association emerged. Further subgroup analysis demonstrated that there was a significant association in Spain population (OR = 0.57, 95%CI: 0.46-0.71), but not in UK population. Also, subgroup analysis revealed that there was a significant correlation between cluster TJ and OA in Spain population (OR = 0.70, 95%CI: 0.58-0.84), although not in UK population. No significant correlation was found between haplogroup T/cluster HV/cluster KU and OA. Our current meta-analysis suggests that mtDNA haplogroup J and cluster TJ correlate with the risk of OA in Spanish population, but the associations in other populations require further investigation.

Genetic variations and risk of placental abruption: A genome-wide association study and meta-analysis of genome-wide association studies.

PubMed

Workalemahu, Tsegaselassie; Enquobahrie, Daniel A; Gelaye, Bizu; Sanchez, Sixto E; Garcia, Pedro J; Tekola-Ayele, Fasil; Hajat, Anjum; Thornton, Timothy A; Ananth, Cande V; Williams, Michelle A

2018-06-01

Accumulating epidemiological evidence points to strong genetic susceptibility to placental abruption (PA). However, characterization of genes associated with PA remains incomplete. We conducted a genome-wide association study (GWAS) of PA and a meta-analysis of GWAS. Participants of the Placental Abruption Genetic Epidemiology (PAGE) study, a population based case-control study of PA conducted in Lima, Peru, were genotyped using the Illumina HumanCore-24 BeadChip platform. Genotypes were imputed using the 1000 genomes reference panel, and >4.9 million SNPs that passed quality control were analyzed. We performed a GWAS in PAGE participants (507 PA cases and 1090 controls) and a GWAS meta-analysis in 2512 participants (959 PA cases and 1553 controls) that included PAGE and the previously reported Peruvian Abruptio Placentae Epidemiology (PAPE) study. We fitted population stratification-adjusted logistic regression models and fixed-effects meta-analyses using inverse-variance weighting. Independent loci (linkage-disequilibrium<0.80) suggestively associated with PA (P-value<5e-5) included rs4148646 and rs2074311 in ABCC8, rs7249210, rs7250184, rs7249100 and rs10401828 in ZNF28, rs11133659 in CTNND2, and rs2074314 and rs35271178 near KCNJ11 in the PAGE GWAS. Similarly, independent loci suggestively associated with PA in the GWAS meta-analysis included rs76258369 near IRX1, and rs7094759 and rs12264492 in ADAM12. Functional analyses of these genes showed trophoblast-like cell interaction, as well as networks involved in endocrine system disorders, cardiovascular diseases, and cellular function. We identified several genetic loci and related functions that may play a role in PA risk. Understanding genetic factors underlying pathophysiological mechanisms of PA may facilitate prevention and early diagnostic efforts. Published by Elsevier Ltd.

Association between non-steroidal anti-inflammatory drug use and melanoma risk: a meta-analysis of 13 studies.

PubMed

Li, Shan; Liu, Yanqiong; Zeng, Zhiyu; Peng, Qiliu; Li, Ruolin; Xie, Li; Qin, Xue; Zhao, Jinmin

2013-08-01

Results of the association between non-steroidal anti-inflammatory drugs (NSAIDs) and melanoma risk have been inconsistent. We performed a meta-analysis of relevant studies to investigate the hypothesis of an association between NSAID use and melanoma risk. Systematic searches of the PubMed and several other databases up to 23 March 2013 were retrieved. All epidemiologic studies regarding NSAIDs and melanoma risk were included. Fixed- or random-effects meta-analytical models were used to calculate relative risk (RR) and corresponding 95 % confidence intervals (CIs). Sensitivity analyses, Galbraith plots, and subgroup analyses were also performed. Six case-control studies including 93,432 melanoma cases and 401,251 controls, six cohort studies consisting of 563,380 subjects, and one randomized controlled trial encompassing 39,876 participants were included in this analysis. Compared to non-use, ever use of any NSAIDs was not statistically significantly associated with melanoma risk based on the random-effects models (RR = 0.97, 95 % CI = 0.90-10.4, p = 0.401). No differences were found in the effects on melanoma risk of aspirin, non-aspirin NSAIDs, and cyclooxygenase-2 inhibitor use overall and stratified by gender. However, a slight reduction in the risk of melanoma by taking aspirin was observed in case-control studies (RR = 0.88, 95 % CI = 0.80-0.96, p = 0.004). Findings from this pooled analysis do not support the hypothesis that NSAID use provides potential benefits in preventing melanoma. More and larger randomized trials, including adequate numbers of patients, are required to further evaluate the relationship between NSAID use and melanoma.