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Sample records for case-control analysis nested

  1. Comparison of nested case-control and survival analysis methodologies for analysis of time-dependent exposure

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    Platt Robert W

    2005-01-01

    Full Text Available Abstract Background Epidemiological studies of exposures that vary with time require an additional level of methodological complexity to account for the time-dependence of exposure. This study compares a nested case-control approach for the study of time-dependent exposure with cohort analysis using Cox regression including time-dependent covariates. Methods A cohort of 1340 subjects with four fixed and seven time-dependent covariates was used for this study. Nested case-control analyses were repeated 100 times for each of 4, 8, 16, 32, and 64 controls per case, and point estimates were compared to those obtained using Cox regression on the full cohort. Computational efficiencies were evaluated by comparing central processing unit times required for analysis of the cohort at sizes 1, 2, 4, 8, 16, and 32 times its initial size. Results Nested case-control analyses yielded results that were similar to results of Cox regression on the full cohort. Cox regression was found to be 125 times slower than the nested case-control approach (using four controls per case. Conclusions The nested case-control approach is a useful alternative for cohort analysis when studying time-dependent exposures. Its superior computational efficiency may be particularly useful when studying rare outcomes in databases, where the ability to analyze larger sample sizes can improve the power of the study.

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

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    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.

  3. Risk factors for gastroenteritis: a nested case-control study.

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    Rodrigo, S; Sinclair, M; Wolfe, R; Leder, K

    2011-04-01

    This nested case-control study investigated the risk factors for gastroenteritis in a cohort using rainwater as their primary domestic water source. Consumption of beef [odds ratio (OR) 2·74, 95% confidence interval (CI) 1·56-4·80], handling of raw fresh chicken in the household (OR 1·52, 95% CI 1·02-2·29) and animal contact (OR 1·83, 95% CI 1·20-2·83) were found to be significant risk factors (P>0·05). Significant protective effects were observed with raw salad prepared at home (OR 0·33, 95% CI 0·18-0·58), consumption of salami (OR 0·60, 95% CI 0·36-0·98), and shellfish (OR 0·31, 95% CI 0·14-0·67). This study provides novel insight into community-based endemic gastroenteritis showing that consumption of beef was associated with increased odds of illness and with a population attributable fraction (PAF) of 57·6%. Detecting such a high PAF for beef in a non-outbreak setting was unexpected.

  4. Consanguinity and neonatal death: a nested case-control study.

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    Reza Chaman

    2014-12-01

    Full Text Available Although numerous studies have found higher rates of abortion and still births following consanguinity (familial marriages, the question of whether consanguinity significantly increases the risk of neonatal death has inadequately been addressed.This study aims to evaluate familial marriage effects on neonatal death in rural areas in Iran.In this nested case-control study, 6900 newbornswho were born in rural areas of Kohgiluyeh and Boyerahmad Province (South-West of Iranwere followed till the end of neonatal period, and neonatal death was the outcome of interest. Subsequently 97 cases and 97 controls were selected in study cohort by using risk set sampling model. Crude and adjusted odds ratios (OR were estimated by usinga conditional logistic regression model.In the final model, prematurity (OR = 5.57, low birthweight (LBW (OR = 7.68, consanguinity (first cousins (OR = 5.23, C-section (OR = 7.27, birth rank more than 3 (OR = 6.95 and birthsinterval less than 24 months (OR = 4.65 showed significant statistical association with neonatal mortality (p < 0.05.According to our findings, after adjusting the effects of other significant risk factors, familial marriageto first cousins is considered asan important risk factor for neonatal death.

  5. Genetic analysis of TOR complex gene variation with human longevity: a nested case-control study of American men of Japanese ancestry.

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    Morris, Brian J; Donlon, Timothy A; He, Qimei; Grove, John S; Masaki, Kamal H; Elliott, Ayako; Willcox, D Craig; Allsopp, Richard; Willcox, Bradley J

    2015-02-01

    The mechanistic target of rapamycin (mTOR) pathway is crucial for life span determination in model organisms. The aim of the present study was to test tagging single-nucleotide polymorphisms that captured most of the genetic variation across key TOR complex 1 (TORC1) and TOR complex 2 (TORC2) genes MTOR, RPTOR, and RICTOR and the important downstream effector gene RPS6KA1 for association with human longevity (defined as attainment of at least 95 years of age) as well as health span phenotypes. Subjects comprised a homogeneous population of American men of Japanese ancestry, well characterized for aging phenotypes and who have been followed for 48 years. The study used a nested case-control design involving 440 subjects aged 95 years and older and 374 controls. It found no association of 6 tagging single-nucleotide polymorphisms for MTOR, 61 for RPTOR, 7 for RICTOR, or 5 for RPS6KA1 with longevity. Of 40 aging-related phenotypes, no significant association with genotype was seen. Thus common genetic variation (minor allele frequency ≥10%) in MTOR, RPTOR, RICTOR, and RPS6KA1 is not associated with extreme old age or aging phenotypes in this population. Further research is needed to assess the potential genetic contribution of other mTOR pathway genes to human longevity, gene expression, upstream and downstream targets, and clinically relevant aging phenotypes.

  6. Maximum likelihood estimation for Cox's regression model under nested case-control sampling

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    Scheike, Thomas; Juul, Anders

    2004-01-01

    Nested case-control sampling is designed to reduce the costs of large cohort studies. It is important to estimate the parameters of interest as efficiently as possible. We present a new maximum likelihood estimator (MLE) for nested case-control sampling in the context of Cox's proportional hazards...... model. The MLE is computed by the EM-algorithm, which is easy to implement in the proportional hazards setting. Standard errors are estimated by a numerical profile likelihood approach based on EM aided differentiation. The work was motivated by a nested case-control study that hypothesized that insulin...

  7. Multilocus Heterozygosity and Coronary Heart Disease: Nested Case-Control Studies in Men and Women

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    Mukamal, Kenneth J.; Jensen, Majken K.; Pers, Tune Hannes;

    2015-01-01

    , homocysteine, adiponectin, or body-mass index. Conclusions: In these parallel nested case-control studies, we found no relationship of multilocus heterozygosity with risk of CHD or its major risk factors. Studies in other populations are needed to rule out associations with lower levels of heterozygosity....

  8. Advantages of the nested case-control design in diagnostic research

    NARCIS (Netherlands)

    Biesheuvel, Cornelis J.; Vergouwe, Yvonne; Oudega, Ruud; Hoes, Arno W.; Grobbee, Diederick E.; Moons, Karel Gm

    2008-01-01

    Background: Despite its benefits, it is uncommon to apply the nested case-control design in diagnostic research. We aim to show advantages of this design for diagnostic accuracy studies. Methods: We used data from a full cross-sectional diagnostic study comprising a cohort of 1295 consecutive patien

  9. Nested case-control study on the risk factors of colorectal cancer

    Institute of Scientific and Technical Information of China (English)

    Kun Chen; Jian Cai; Xi-Yong Liu; Xi-Yuan Ma; Kai-Yan Yao; Shu Zheng

    2003-01-01

    AIM: To investigate the risk factors of colon cancer andrectal cancer.METHODS: A nested case-control study was conducted ina cohort of 64 693 subjects who participated in a colorectalcancer screening program from 1989 to 1998 in Jiashancounty, Zhejiang, China. 196 cases of colorectal cancer weredetected from 1990 to 1998 as the case group and 980non-colorectal cancer subjects, matched with factors of age,gender, resident location, were randomly selected from the64 693 cohort as controls. By using univariate analysis andmutivariate conditional logistic regression analysis, the oddsratio (OR) and its 95 % confidence interval (95 %CI) werecalculated between colorectal cancer and personal habits,dietary factors, as well as intestinal related symptoms.RESULTS: The mutivariate analysis results showed that aftermatched with age, sex and resident location, mucous bloodstool history and mixed sources of drinking water were closelyassociated with colon cancer and rectal cancer, OR values forthe mucous blood stool history were 3.508 (95 %CI: 1.370-8.985) and 2.139 (95 %CI: 1.040-4.402) respectively; for themixed drinking water sources, 2.387 (95 %CI: 1.243-4.587)and 1.951 (95 %CI: 1.086-3.506) respectively. All reachedthe significant level with a P-value less than 0.05.CONCLUSION: The study suggested that mucous bloodstool history and mixed sources of drinking water were therisk factors of colon cancer and rectal cancer. There was noany significant association between dietary habits and theincidence of colorectal cancer.

  10. ESTIMATING HAZARD RATIOS IN NESTED CASE-CONTROL STUDIES BY MANTEL-HAENSZEL METHOD

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    张忠占

    2001-01-01

    In this article, a class of Mantel-Haenszel type estimators of hazard ratios in proportional hazards model is presented for simple nested case-control study. The estimators have the form of the Mantel-Haenszel estimator of odds ratios, and it is shown that the estimators are dually consistent, and asymptotically normal. Dually consistently estimated covariance matrices of the proposed estimators are also developed. An example is given to illustrate the estimators.

  11. Suicide by people in a community justice pathway: population-based nested case-control study.

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    King, Carlene; Senior, Jane; Webb, Roger T; Millar, Tim; Piper, Mary; Pearsall, Alison; Humber, Naomi; Appleby, Louis; Shaw, Jenny

    2015-08-01

    The elevated risk of suicide in prison and after release is a well-recognised and serious problem. Despite this, evidence concerning community-based offenders' suicide risk is sparse. We conducted a population-based nested case-control study of all people in a community justice pathway in England and Wales. Our data show 13% of general population suicides were in community justice pathways before death. Suicide risks were highest among individuals receiving police cautions, and those having recent, or impending prosecution for sexual offences. Findings have implications for the training and practice of clinicians identifying and assessing suicidality, and offering support to those at elevated risk.

  12. Antipsychotic Medications and Risk of Acute Coronary Syndrome in Schizophrenia: A Nested Case-Control Study

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    Liu, Hsing-Cheng; Yang, Shu-Yu; Liao, Ya-Tang; Chen, Chiao-Chicy; Kuo, Chian-Jue

    2016-01-01

    Background This study assessed the risk of developing acute coronary syndrome requiring hospitalization in association with the use of certain antipsychotic medications in schizophrenia patients. Methods A nationwide cohort of 31,177 inpatients with schizophrenia between the ages of 18 and 65 years whose records were enrolled in the National Health Insurance Research Database in Taiwan from 2000 to 2008 and were studied after encrypting the identifications. Cases (n = 147) were patients with subsequent acute coronary syndrome requiring hospitalization after their first psychiatric admission. Based on a nested case-control design, each case was matched with 20 controls for age, sex and the year of first psychiatric admission using risk-set sampling. The effects of antipsychotic agents on the development of acute coronary syndrome were assessed using multiple conditional logistic regression and sensitivity analyses to confirm any association. Results We found that current use of aripiprazole (adjusted risk ratio [RR] = 3.68, 95% CI: 1.27–10.64, p<0.05) and chlorpromazine (adjusted RR = 2.96, 95% CI: 1.40–6.24, p<0.001) were associated with a dose-dependent increase in the risk of developing acute coronary syndrome. Although haloperidol was associated with an increased risk (adjusted RR = 2.03, 95% CI: 1.20–3.44, p<0.01), there was no clear dose-dependent relationship. These three antipsychotic agents were also associated with an increased risk in the first 30 days of use, and the risk decreased as the duration of therapy increased. Sensitivity analyses using propensity score-adjusted modeling showed that the results were similar to those of multiple regression analysis. Conclusions Patients with schizophrenia who received aripiprazole, chlorpromazine, or haloperidol could have a potentially elevated risk of developing acute coronary syndrome, particularly at the start of therapy. PMID:27657540

  13. Determinants of skilled attendance for delivery in Northwest Ethiopia: a community based nested case control study

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    Mengesha Zelalem Birhanu

    2013-02-01

    Full Text Available Abstract Background The fifth Millennium Development Goal calls for a reduction of maternal mortality ratio by 75% between 1990 and 2015. A key indicator to measure this goal is the proportion of births attended by skilled health personnel. The maternal mortality ratio of Ethiopia is 676 deaths per 100,000 live births. Skilled birth attendance is correlated with lower maternal mortality rates globally and in Sub-Saharan Africa. However, the proportion of births with a skilled attendant is only 10% in Ethiopia. Therefore identifying the determinants of skilled attendance for delivery is a priority area to give policy recommendations. Methods A community based nested case control study was conducted from October 2009 – August 2011 at the University of Gondar health and demographic surveillance systems site located at Dabat district, Northwest Ethiopia. Data were obtained from the infant mortality prospective follow up study conducted to identify the determinants of infant survival. A pretested and structured questionnaire via interview was used to collect data on the different variables. Logistic regression analysis was used to identify the determinants of skilled birth attendance. Strength of the association was assessed using odds ratio with 95% CI. Results A total of 1065 mothers (213 cases and 852 controls were included in the analysis. Among the cases, 166 (77.9% were from urban areas. More than half (54% of the cases have secondary and above level of education. Secondary and above level of education [AOR (95%CI = 2.8 (1.29, 3.68] and urban residence [AOR (95%CI = 8.8 (5.32, 14.46] were associated with skilled attendance for delivery. Similarly, women who had ANC during their pregnancy four or more times [AOR (95%CI = 2.8 (1.56, 4.98] and who own TV [AOR (95%CI = 2.5 (1.32, 4.76] were more likely to deliver with the assistance of a skilled attendant. Conclusions Women’s education, place of residence, frequency of antenatal

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

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

    2015-01-01

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

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

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    Cristina Lopez-del Burgo

    2015-07-01

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

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

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

    2015-08-01

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

  17. Helicobacter pylori infection and gastric cancer: evidence fron a retrospective cohort study and nested case-control study in China

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    Run-Tian Wang; Chou-Wen Zhu; Hai Yu; Yu-Jun Cong; Sbu Zheng; Bing-Quan Wu; Tao Wang; Kun Chen; Ji-Yao Wang; Jie-Ping Zhang; San-Ren Lin; Yi-Min Zhu; Wen-Ming Zhang; Yu-Xin Cao

    2002-01-01

    AIM: To explore the association between Helicobacter pylori (Hp) infection and risk of gastric cancer in China. METHODS: Utilizing gastroendoscopic biospsy tissue banks accumulated from1980 to1988 in Shandong, Zhejiang, and Jiangsu, where stomach cancer incidence was high, during stomach cancer screening conducted by Health Science Center of Peking University, School of Medicine of Zhejiang University, and Zhongshan Hospital of Fudan University. Warthin Starry silver staining method was applied to determine H. pyloriinfection status of biopsies collected during gastroendoscopic examination. In the retrospective study, the subjects were divided into two cohorts, the exposure cohort was positive H. pyloriinfection, and the non-exposure cohort was negative. Death from stomach cancer was determined as the outcome of the study. Logistic regression and Cox regression were applied to analyze the association between Helicobacterpyloriinfection and gastric cancer risk. In the nested case-control study, there were 28 deaths from gastric cancer in the fields of Muping, Shandong province, and Zhoushan, Zhejiang provinces. 4 controls were matched to each case on the basis of age (±5 years old), sex, residential place at the same time entered into the study. Conditional logistic regression analysis was used to analyze the data.RESULTS: There were a total of 2 719 subjects (male 1 399,female 1 320) with gastroendoscopic biopsies stored available treated as a cohort. H. pyloripositive cohort included 1 671 subjects (61.5 %) and H. pylorinegative cohort 1 048 subjects(38.5 %). These subjects were followed up for 1-19 years, averaged 10.88 years. The outcome of death from stomach cancer in the exposure cohort was 33, and in the non-exposure cohort 11. After adjustment for age and sex, RR=1.9850 (P=0.0491), 95 % CI was 1.0026, and 3.9301. The results of conditional logistic regression showed an OR of 4.467 and 95 % CI of 1.161, and 17.190 for the nested case control study

  18. Neonatal Mortality Risk Factors in a Rural Part of Iran: A Nested Case-Control Study

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    R Chaman

    2009-03-01

    Full Text Available "nBackground: Due to complex causal framework of neonatal mortality, improvement of this health indicator is quite gradual and it's decreasing trend is not as great as other health indicators such as infant and under 5 mortality rates.This study was conducted to evaluate neonatal mortality risk factors based on nested case-control design."nMethods:  The study population was 6900 neonates who were born in rural areas of Kohgiluyeh and Boyerahmad province (South of Iran. They were under follow up till the end of neonatal period and the outcome of interest was neonatal death. By using risk set sampling method, 97 cases and 97 controls were selected in study cohort."nResults: Prematurity (OR= 5.57, LBW (OR= 7.68, C-section (OR= 7.27, birth rank more than 3 (OR=6.95 and birth spac­ing less than 24 months (OR= 4.65 showed significant statistical association (P< 0.05 with neonatal mortality. The Popula­tion Attributable Fraction (PAF was 0.45 for LBW, 0.40 for prematurity, 0.28 for C-section, 0.30 for birth rank more than 3, and 0.16 for birth spacing less than 24 months."nConclusion: Prematurity, low birth weight, C-section, birth spacing less than 24 months and birth rank more than 3 are impor­tant risk factors for neonatal mortality.

  19. Antidepressants and Valvular Heart Disease: A Nested Case-Control Study in Taiwan.

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    Lin, Chia-Hui; Hsiao, Fei-Yuan; Liu, Yen-Bin; Gau, Susan Shur-Fen; Wang, Chi-Chuan; Shen, Li-Jiuan

    2016-04-01

    Empirical evidence regarding the association between antidepressants and valvular heart disease (VHD) is scarce.Using Taiwan's National Health Insurance Research database, this nested case-control study assessed the association between antidepressants and VHD in a Chinese population.Among a cohort of patients who used at least 3 prescription antidepressants, 874 cases with VHD and 3496 matched controls (1:4 ratio) were identified. Conditional logistic regression models were used to examine the timing, duration, dose and type of antidepressants use, and the risk of VHD.Current use of antidepressants was associated with a 1.4-fold increase in the risk of VHD (adjusted odds ratio [aOR] 1.44; 95% confidence interval [CI] 1.17-1.77). Among current users, a dose-response association was observed in terms of the cumulative duration and the cumulative antidepressant dose. Significantly higher risks of VHD were observed among the current users of tricyclic antidepressants (aOR 1.40 [1.05-1.87]).We found that the use of antidepressants was associated with a greater risk of VHD and that the risks varied according to different antidepressants.

  20. Varenicline and Risk of Self-Harm: A Nested Case-Control Study

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    Martins, Diana; Yao, Zhan; Mamdani, Muhammad M.; Juurlink, David N.; Gomes, Tara; Antoniou, Tony

    2016-01-01

    Background Smoking remains a serious public health concern. Pharmacotherapy for smoking cessation, including bupropion and varenicline, are proven means to increase quit rates. Post-marketing reports describing suicidal behaviours have raised concerns about the safety of varenicline. However, whether varenicline imparts a higher risk of suicide relative to bupropion remains uncertain. Methods A population-based nested case-control study in Ontario, Canada, from April 1, 2011 to March 31, 2015 was conducted. Subjects were residents of Ontario aged 18 years and older with publicly funded drug coverage receiving either bupropion or varenicline for smoking cessation. We defined cases were those with a hospitalization or emergency department visit for suicide or non-fatal self-harm within 90 days of treatment. For each case, we identified up to fifty controls from the same cohort matched on age, sex, history of self-harm, use of selected psychotropic medications, alcohol abuse and prior admission to a mental health unit. Adjusted odds ratio were used to compare the risk of suicide/self-harm of varenicline to bupropion. Results We identified 331 cases and 5,346 matched-controls. Following adjustment for potential confounders, we found that varenicline was not associated with an increased risk of suicide/self-harm relative to bupropion (adjusted odds ratio 1.15; 95% confidence interval 0.71 to 1.87). Interpretation Treatment with varenicline does not appear to significantly increase the risk of suicide or self-harm relative to bupropion. PMID:27662654

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

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

    2015-03-01

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

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

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

    2011-01-01

    Objectives To characterise the risk of admission to hospital for hyperkalaemia in elderly patients treated with trimethoprim-sulfamethoxazole in combination with spironolactone. Design Population based nested case-control study. Setting Ontario, Canada, from 1 April 1992 to 1 March 2010. Participants Cases were residents of Ontario aged 66 years or above receiving chronic treatment with spironolactone and admitted to hospital with hyperkalaemia within 14 days of receiving a prescription for either trimethoprim-sulfamethoxazole, amoxicillin, norfloxacin, or nitrofurantoin. Up to four controls for each case were identified from the same cohort, matched on age, sex, and presence or absence of chronic kidney disease and diabetes, and required to have received one of the study antibiotics within 14 days before the case’s index date. Main outcome measures Odds ratio for association between admission to hospital with hyperkalaemia and receipt of a study antibiotic in the preceding 14 days, adjusted for conditions and drugs that may influence risk of hyperkalaemia. Results During the 18 year study period, 6903 admissions for hyperkalaemia were identified, 306 of which occurred within 14 days of antibiotic use. Of these, 248 (81%) cases were matched to 783 controls. 10.8% (17 859/165 754) of spironolactone users received at least one prescription for trimethoprim-sulfamethoxazole. Compared with amoxicillin, prescription of trimethoprim-sulfamethoxazole was associated with a marked increase in the risk of admission to hospital for hyperkalaemia (adjusted odds ratio 12.4, 95% confidence interval 7.1 to 21.6). The population attributable fraction was 59.7%, suggesting that approximately 60% of all cases of hyperkalaemia in older patients taking spironolactone and treated with an antibiotic for a urinary tract infection could be avoided if trimethoprim-sulfamethoxazole was not prescribed. Treatment with nitrofurantoin was also associated with an increase in the risk of

  3. Risk factors for levofloxacin-nonsusceptible Streptococcus pneumoniae in community-acquired pneumococcal pneumonia: a nested case-control study.

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    Kang, C-I; Song, J-H; Kim, S H; Chung, D R; Peck, K R; So, T M; Hsueh, P-R

    2014-01-01

    This study was performed to evaluate the clinical features of community-onset levofloxacin-nonsusceptible pneumococcal pneumonia and to identify risk factors for levofloxacin resistance. Using the database of a surveillance study of community-acquired pneumococcal infections in Asian countries, we conducted a nested case-control study to identify risk factors for levofloxacin-nonsusceptible S. pneumoniae in community-acquired pneumonia in adults. Of 981 patients with pneumococcal pneumonia, 46 (4.7 %) had levofloxacin-nonsusceptible S. pneumoniae, of whom 39 evaluable cases were included in the analysis. All cases were from Korea, Taiwan, and Hong Kong. Among patients with levofloxacin-susceptible S. pneumoniae, 490 controls were selected based on patient country. Of the 39 cases of levofloxacin-nonsusceptible pneumococcal pneumonia, 23 (59.0 %) were classified as healthcare-associated, while 164 (33.5 %) of the 490 controls of levofloxacin-susceptible S. pneumoniae (P = 0.001) were classified as healthcare-associated. Multivariate analysis showed that previous treatment with fluoroquinolones, cerebrovascular disease, and healthcare-associated infection were significantly associated with levofloxacin-nonsusceptible pneumococcal pneumonia (all P < 0.05). Levofloxacin-nonsusceptible pneumococci pose an important new public health threat in our region, and more information on the emergence and spread of these resistant strains will be necessary to prevent spread throughout the population.

  4. Blood fatty acid patterns are associated with prostate cancer risk in a prospective nested case-control study

    Science.gov (United States)

    Yang, Meng; Ayuningtyas, Azalea; Kenfield, Stacey A.; Sesso, Howard D.; Campos, Hannia; Ma, Jing; Stampfer1, Meir J.; Chavarro, Jorge E.

    2016-01-01

    Background Circulating fatty acids are highly correlated with each other and analyzing fatty acid patterns could better capture their interactions and their relation to prostate cancer. We aimed to assess the associations between data-derived blood fatty acid patterns and prostate cancer risk. Methods We conducted a nested case-control study in the Physicians’ Health Study. Fatty acids levels were measured in whole blood samples of 476 cases and their matched controls by age and smoking status. Fatty acid patterns were identified using principal component analysis. Conditional logistic regression was used to estimate odds ratio (OR) and 95% confidence interval (CI). Results Two patterns explaining 40.9% of total variation in blood fatty acid levels were identified. Pattern 1, which mainly reflects polyunsaturated fatty acid metabolism, was suggestively positively related to prostate cancer risk (ORquintile 5 vs. quintile 1=1.37, 95%CI=0.91–2.05, Ptrend=0.07). Pattern 2, which largely reflects de novo lipogenesis, was significantly associated with higher prostate cancer risk (ORquintile5 vs quintile1=1.63, 95%CI=1.04–2.55, Ptrend=0.02). This association was similar across tumor stage, grade, clinical aggressiveness categories and follow-up time. Conclusion The two patterns of fatty acids we identified were consistent with known interactions between fatty acid intake and metabolism. A pattern suggestive of higher activity in the de novo lipogenesis pathway was related to higher risk of prostate cancer. PMID:27488836

  5. The association between component malalignment and post-operative pain following navigation-assisted total knee arthroplasty: results of a cohort/nested case-control study.

    Science.gov (United States)

    Czurda, Thomas; Fennema, Peter; Baumgartner, Martin; Ritschl, Peter

    2010-07-01

    Previous studies have noted an adverse relationship between implant malalignment during total knee arthroplasty (TKA) and post-operative pain. Although some evidence exists indicating that computer-assisted surgical navigation for TKA can improve the accuracy of component alignment, its impact on clinical outcomes is currently unknown. The dual goals of the present cohort/nested case-control study were to (1) compare self-reported responses to the Western Ontario-McMaster Osteoarthritis Index (WOMAC) questionnaire between computer-assisted TKA (123 patients) using the imageless PiGalileo navigation system and conventional TKA (207 patients) [cohort analysis], and (2) to investigate a potential association between malalignment and post-operative pain in 19 painful knees and 19 asymptomatic knees obtained from the cohort analysis using matched sampling [nested case-control study]. In the cohort analysis, a relevant but non-significant (P = 0.06) difference in the occurrence of chronic pain was observed between the navigated (12%) and conventional arms (20%). Median post-operative WOMAC pain score was 100 (range, 50-100) in the conventional group and 100 (range, 65-100) in the navigated group. However, the Mann-Whitney test revealed a significant difference in favor of the navigated group (P = 0.01). In the nested case-control analysis, radiological outcomes and computer tomography (CT) measurements of femoral rotation were compared between the groups. The CT rotation measurements yielded evidence of a relationship between post-operative pain and incorrect rotational alignment of the femoral component of more than 3 degrees (OR: 7; 95% CI: 1.2-42; P = .033). In conclusion, there was no clinical benefit to computer-assisted navigation; however, a statistically significant relationship was observed between incorrect rotational alignment of the femoral component and symptoms of post-operative pain following TKA.

  6. A nested case-control study of maternal-neonatal transmission of hepatitis B virus in a Chinese population

    Institute of Scientific and Technical Information of China (English)

    Li-Zhang Chen; Wen-Qi Zhou; Shu-Shan Zhao; Zhi-Yu Liu; Shi-Wu Wen

    2011-01-01

    AIM: To examine the determinants of maternal-neo?natal transmission of hepatitis B virus (HBV).METHODS: A nested case-control study was conducted in Changsha, Hunan, People's Republic of China from January 1, 2005 to September 31, 2006. To avoid po?tential maternal blood contamination, we collected vein blood of newborns immediately after birth and before initial hepatitis B vaccination to determine the HBV in?fection status of the newborn. For each HBsAg-positive infant, one HBsAg-negative infant born to an HBsAg-positive mother was matched by hospital at birth (same), gender (same), and date of birth (within 1 mo). A face-to-face interview was conducted to collect clinical and epidemiological data. Conditional logistic regression analysis was used to estimate the independent effects of various determinants on maternal-neonatal transmis?sion of HBV.RESULTS: A total of 141 HBsAg-positive infants and 141 individually matched HBsAg-negative infants were included in the final analysis. Maternal first-degree family history of HBV infection, intrahepatic cholesta-sis, and premature rupture of membranes were risk factors for perinatal transmission of HBV, whereas sys?tematic treatment and HBV immunoglobulin injections for mothers with HBV infection were protective factors for maternal-neonatal transmission of HBV, after ad?justment for potential confounding factors.CONCLUSION: For HBsAg-positive mothers, system?atic treatment, HBV immunoglobulin administration, and controlling intrahepatic cholestasis and pregnancy complications may reduce the incidence of perinatal transmission of HBV.

  7. Polymorphic variants in PTGS2 and prostate cancer risk: results from two large nested case-control studies.

    Science.gov (United States)

    Danforth, Kim N; Hayes, Richard B; Rodriguez, Carmen; Yu, Kai; Sakoda, Lori C; Huang, Wen-Yi; Chen, Bingshu E; Chen, Jinbo; Andriole, Gerald L; Calle, Eugenia E; Jacobs, Eric J; Chu, Lisa W; Figueroa, Jonine D; Yeager, Meredith; Platz, Elizabeth A; Michaud, Dominique S; Chanock, Stephen J; Thun, Michael J; Hsing, Ann W

    2008-03-01

    Chronic inflammation has been hypothesized to increase prostate cancer risk. Prostaglandin-endoperoxide synthase 2 (PTGS2) encodes the proinflammatory cyclooxygenase 2 enzyme believed to be the rate-limiting step in the synthesis of prostaglandins, important mediators of inflammation. We investigated associations between PTGS2 polymorphisms and prostate cancer risk among 2321 prostate cancer cases and 2560 controls in two large case-control studies nested within the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial and the Cancer Prevention Study II Nutrition Cohort. Five single nucleotide polymorphisms (SNPs) (rs5277, rs20432, rs4648276, rs5275 and rs689470) were examined in SNP and haplotype analyses (five SNPs in PLCO and four SNPs in the Nutrition Cohort). In PLCO, the Ex10 +837 T>C marker (rs5275) was initially associated with prostate cancer risk (P-trend = 0.02) but became non-significant after adjustment for multiple comparisons (P = 0.08); this SNP showed no association with prostate cancer risk in the Nutrition Cohort (P-trend = 0.54) or in an analysis pooling the two cohorts (P-trend = 0.20). No other SNP was associated with prostate cancer risk in PLCO or the Nutrition Cohort individually or combined. Haplotype analyses suggested an association between PTGS2 variants in PLCO alone (global P = 0.007), but not in the Nutrition Cohort (global P = 0.78) or pooled analysis (global P = 0.18). In conclusion, despite the potential importance of inflammation in prostate carcinogenesis, results from our large study of five PTGS2 SNPs does not support a strong association between PTGS2 variants and prostate cancer risk in non-Hispanic white men.

  8. Oral bisphosphonates do not increase the risk of severe upper gastrointestinal complications: A nested case-control study

    OpenAIRE

    Ghirardi, Arianna; Scotti, Lorenza; Vedova, Gianluca; D'Oro, Luca; Lapi, Francesco; Cipriani, Francesco; Caputi, Achille; Vaccheri, Alberto; Gregori, Dario; Gesuita, Rosaria; Vestri, Annarita; Staniscia, Tommaso; Mazzaglia, Giampiero; Corrao, Giovanni; Sessa, E

    2014-01-01

    textabstractBackground: Data on the effect of oral bisphosphonates (BPs) on risk of upper gastrointestinal complications (UGIC) are conflicting. We conducted a large population-based study from a network of Italian healthcare utilization databases aimed to assess the UGIC risk associated with use of BPs in the setting of secondary prevention of osteoporotic fractures.Methods: A nested case-control study was carried out within a cohort of 68,970 patients aged 45 years or older, who have been h...

  9. Incidence and Risk Factors of De novo Stress Urinary Incontinence after Pelvic Floor Reconstruction: A Nested Case-control Study

    Science.gov (United States)

    Wang, Shi-Yan; Cao, Ting-Ting; Wang, Run-Zhi; Yang, Xin; Sun, Xiu-Li; Wang, Jian-Liu

    2017-01-01

    Background: Some patients with pelvic organ prolapse may suffer from lower urinary tract symptoms (LUTS), especially stress urinary incontinence (SUI) named de novo SUI after pelvic floor reconstruction. This study aimed to investigate the incidence and risk factors of de novo SUI. Methods: This is a nested case-control study of 533 patients who underwent pelvic floor reconstruction due to pelvic organ prolapse (POP) at the Department of Gynecology in Peking University People's Hospital from January 2011 to March 2013. According to the inclusion and exclusion criteria, 401 patients were enrolled in the study with the follow-up rate of 74.8% (101 patients lost to follow-up). There were 75 patients with de novo SUI postoperatively. According to the ratio of 1:3, we ensured the number of control group (n = 225). The preoperative urinary dynamics, POP-quantification scores, and LUTS were compared between the two groups by univariate and multivariate logistic regression analyses to investigate the risk factors of de novo SUI. Results: The incidence of de novo SUI was 25% (75/300). Univariate analysis showed that the ratio of lower urinary tract obstruction (LUTO) before surgery in de novo SUI group was significantly higher than the control group (odds ratio [OR] = 2.1, 95% confidence interval [CI] [1.1–4.0], P = 0.022). The interaction test of LUTO and other factors displayed that Aa value was an interaction factor. With the increasing score of Aa, the incidence of de novo SUI become higher (OR = 2.1, 95% CI [1.0–3.7], P = 0.045). After multivariable adjustment, multiple regression analysis showed that LUTO was independently associated with a greater risk of de novo SUI after pelvic floor surgery (OR = 2.3, 95% CI [1.2–4.6], P = 0.013). Conclusions: Preoperative LUTO in patients with POP is a high-risk factor of de novo SUI, and high score of Aa-point is related to the occurrence of de novo SUI, which might be due to the outlet obstruction caused by bladder

  10. Urinary flavonoid excretion and risk of acute coronary syndrome in a nested case-control study123

    DEFF Research Database (Denmark)

    Bredsdorff, Lea; Obel, Tina; Dethlefsen, Claus

    2013-01-01

    Background: Epidemiologic studies have suggested that a higher intake of flavonoids may be associated with lower risk of ischemic heart disease. However, the traditional estimation of flavonoid intake by using dietary assessment methods is affected by subjective measures. Objective: We examined...... whether the objective measurement of dietary flavonoids excreted in urine is associated with lower risk of acute coronary syndrome (ACS). Design: A case-control study was nested in the Danish Diet, Cancer and Health cohort study. Cases were identified in participants who had received a first-time ACS...... diagnosis in the Danish National Patient Registry after the time of enrollment into the Diet, Cancer and Health study. The excretion of 10 flavonoids, which represent 5 subclasses, was measured in spot urine samples by using liquid chromatography–mass spectrometry. Results: A total of 393 eligible cases...

  11. Exposure assessment and modeling of quartz in Swedish iron foundries for a nested case-control study on lung cancer.

    Science.gov (United States)

    Andersson, Lena; Bryngelsson, Ing-Liss; Ngo, Yen; Ohlson, Carl-Göran; Westberg, Håkan

    2012-01-01

    Exposure assessment of quartz in Swedish iron foundries was performed based on historical and current measurement data. To evaluate the exposure-response relationship between quartz exposure and lung cancer, we modeled quartz exposure from our database of measurements using determinants job title, time period, and company. Based on these modeled exposure data, we conducted a nested case-control evaluation. In our database, the overall individual, daily time-weighted average (TWA) quartz concentrations of current and historical data varied between 0.0018 and 4.9 mg/m(3), averaging 0.083 mg/m(3). Job titles with mean TWAs for the whole study period exceeding the European Union recommended occupational exposure limit of 0.05 mg/m(3) were fettlers (0.087 mg/m(3)), furnace and ladle repair (0.42 mg/m(3)), and maintenance (0.054 mg/m(3)) workers. The mixed model analysis demonstrated significant determinants on the job level for furnace and ladle repair (β = 4.06; 95% confidence interval [CI] 2.78-5.93). For all jobs, significantly higher exposure levels occurred only during the first time period, 1968-1979 (β = 2.08; 95% CI 1.75-2.47), and a decreasing but not significant trend was noted for the three following 10-year time periods up to 2006 (β = 1.0, 0.96 and 1, respectively). Two iron foundries had significantly higher quartz concentration levels than the others (β = 1.31; 95% CI 1.00-1.71 and β = 1.63; 95% CI 1.00-2.65, respectively). The individual cumulative quartz exposure measures were categorized in low, medium, and high exposure (0.5-0.05 mg/m(3) of quartz. To conclude, certain foundry workers are still exposed to high levels of quartz, but an increased risk of lung cancer caused by quartz exposure in these Swedish iron foundries could not be confirmed at our exposure levels.

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

    Science.gov (United States)

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

    2013-12-15

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

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

    Directory of Open Access Journals (Sweden)

    Li-Ju Chen

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

  14. Lack of Significant Effects of Chlamydia trachomatis Infection on Cervical Adenocarcinoma Risk: Nested Case-Control Study

    Science.gov (United States)

    Smelov, Vitaly; Gheit, Tarik; Sundström, Karin; Ploner, Alexander; McKay-Chopin, Sandrine; Eklund, Carina; Tommasino, Massimo; Dillner, Joakim

    2016-01-01

    Background A role of Chlamydia trachomatis in HPV-induced cervical carcinogenesis has been reported for cervical cancer but studies on cervical adenocarcinoma are limited. Methods A total of 1,553 cervical smears taken up to 26 years before diagnosis in a large population-based nested case-control study of cervical adenocarcinoma (AC, 132 cases with matched controls), and adenocarcinoma in situ (AIS, 159 cases with matched controls) were tested for C. trachomatis and HPV DNA by a type-specific PCR bead-based multiplex genotyping (TS-MPG) assay. Results Only 1.7% of samples were positive for C. trachomatis, with no significant differences between AC/AIS cases and controls. HPV-positivity was detected in 49.3% of C. trachomatis-negative and 65.4% C. trachomatis-positive samples, respectively. Conclusions A large prospective study did not find any risk for cervical adenocarcinoma and/or AIS conferred by C. trachomatis infection. Impact C. trachomatis appears not to be involved in cervical adenocarcinomas. PMID:27227411

  15. Lack of Significant Effects of Chlamydia trachomatis Infection on Cervical Adenocarcinoma Risk: Nested Case-Control Study.

    Directory of Open Access Journals (Sweden)

    Vitaly Smelov

    Full Text Available A role of Chlamydia trachomatis in HPV-induced cervical carcinogenesis has been reported for cervical cancer but studies on cervical adenocarcinoma are limited.A total of 1,553 cervical smears taken up to 26 years before diagnosis in a large population-based nested case-control study of cervical adenocarcinoma (AC, 132 cases with matched controls, and adenocarcinoma in situ (AIS, 159 cases with matched controls were tested for C. trachomatis and HPV DNA by a type-specific PCR bead-based multiplex genotyping (TS-MPG assay.Only 1.7% of samples were positive for C. trachomatis, with no significant differences between AC/AIS cases and controls. HPV-positivity was detected in 49.3% of C. trachomatis-negative and 65.4% C. trachomatis-positive samples, respectively.A large prospective study did not find any risk for cervical adenocarcinoma and/or AIS conferred by C. trachomatis infection.C. trachomatis appears not to be involved in cervical adenocarcinomas.

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

    Directory of Open Access Journals (Sweden)

    Ladislav Tomasek

    2013-03-01

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

  17. Risk of Prostate Cancer after Trans Urethral Resection of BPH: A Cohort and Nested Case-Control Study

    Energy Technology Data Exchange (ETDEWEB)

    Karlsson, Camilla T., E-mail: Camilla.thellenberg@onkologi.umu.se [Department of Radiation Sciences, Oncology, Umeå University, SE-901 87 Umeå (Sweden); Wiklund, Fredrik; Grönberg, Henrik [Department of Medical Epidemiology and Biostatistics, Karolinska Institute, Stockholm SE-171 77 (Sweden); Bergh, Anders [Department of Medical Biosciences, Pathology, Umeå University, SE-901 87 Umeå (Sweden); Melin, Beatrice [Department of Radiation Sciences, Oncology, Umeå University, SE-901 87 Umeå (Sweden)

    2011-11-08

    Epidemiological and experimental evidence suggests that inflammation plays a role in both prostate cancer (PCa) and benign prostate hyperplasia (BPH). This study evaluates the risk of PC after transurethral resection (TURP) for BPH and estimates the PCa risk related to presence of inflammation in the resected material. The Pathology Department at the University Hospital of Umeå (Umeå, Sweden) identified BPH cases (n = 7,901) that underwent TURP between 1982 and 1997. Using these pathological specimens, we compared the incidence of PCa in the cohort to the population and calculated the standardized incidence and mortality ratios (SIR and SMR). Inflammation, the androgen receptor (AR), and p53 were evaluated in a nested case-control study of 201 cases and controls. Inflammation was graded severe or mild-moderate. In the follow-up period after TURP, cases developed prostate cancer and the controls did not. After TURP, SIR for prostate cancer increased [1.26, CI 95% (1.17–1.35) ], whereas SMR decreased [0.59, CI 95% (0.47–0.73) ]. Presence of inflammation at the time of TURP did not differ between cases and controls nor were there differences in p53 or AR staining. The data suggest a small increased risk of PCa after TURP and decreased PCa mortality. Inflammation at the time of TURP is not associated with PCa risk in this material. The increased PCa risk may be attributed to increased surveillance and PSA screening.

  18. Risk of Prostate Cancer after Trans Urethral Resection of BPH: A Cohort and Nested Case-Control Study.

    Science.gov (United States)

    Karlsson, Camilla T; Wiklund, Fredrik; Grönberg, Henrik; Bergh, Anders; Melin, Beatrice

    2011-11-08

    Epidemiological and experimental evidence suggests that inflammation plays a role in both prostate cancer (PCa) and benign prostate hyperplasia (BPH). This study evaluates the risk of PC after transurethral resection (TURP) for BPH and estimates the PCa risk related to presence of inflammation in the resected material. The Pathology Department at the University Hospital of Umeå (Umeå, Sweden) identified BPH cases (n = 7,901) that underwent TURP between 1982 and 1997. Using these pathological specimens, we compared the incidence of PCa in the cohort to the population and calculated the standardized incidence and mortality ratios (SIR and SMR). Inflammation, the androgen receptor (AR), and p53 were evaluated in a nested case-control study of 201 cases and controls. Inflammation was graded severe or mild-moderate. In the follow-up period after TURP, cases developed prostate cancer and the controls did not. After TURP, SIR for prostate cancer increased [1.26, CI 95% (1.17-1.35)], whereas SMR decreased [0.59, CI 95% (0.47-0.73)]. Presence of inflammation at the time of TURP did not differ between cases and controls nor were there differences in p53 or AR staining. The data suggest a small increased risk of PCa after TURP and decreased PCa mortality. Inflammation at the time of TURP is not associated with PCa risk in this material. The increased PCa risk may be attributed to increased surveillance and PSA screening.

  19. Diarrhoea in general practice: when should a Clostridium difficile infection be considered? Results of a nested case-control study.

    Science.gov (United States)

    Hensgens, M P M; Dekkers, O M; Demeulemeester, A; Buiting, A G M; Bloembergen, P; van Benthem, B H B; Le Cessie, S; Kuijper, E J

    2014-12-01

    Clostridium difficile infections (CDIs) are frequent in hospitals, but also seem to increase in the community. Here, we aim to determine the incidence of CDI in general practice and to evaluate current testing algorithms for CDI. Three Dutch laboratories tested all unformed faeces (12,714) for C. difficile when diagnostic testing (for any enteric pathogen) was requested by a general practitioner (GP). Additionally, a nested case-control study was initiated, including 152 CDI patients and 304 age and sex-matched controls. Patients were compared using weighted multivariable logistic regression. One hundred and ninety-four samples (1.5%) were positive for C. difficile (incidence 0.67/10,000 patient years). This incidence was comparable to that of Salmonella spp. Compared with diarrhoeal controls, CDI was associated with more severe complaints, underlying diseases, antibiotic use and prior hospitalization. In our study, GPs requested a test for C. difficile in 7% of the stool samples, thereby detecting 40% of all CDIs. Dutch national recommendations advise testing for C. difficile when prior antibiotic use or hospitalization is present (18% of samples). If these recommendations were followed, 61% of all CDIs would have been detected. In conclusion, C. difficile is relatively frequent in general practice. Currently, testing for C. difficile is rare and only 40% of CDI in general practice is detected. Following recommendations that are based on traditional risk factors for CDI, would improve detection of CDI.

  20. Risk of Prostate Cancer after Trans Urethral Resection of BPH: A Cohort and Nested Case-Control Study

    Directory of Open Access Journals (Sweden)

    Beatrice Melin

    2011-11-01

    Full Text Available Epidemiological and experimental evidence suggests that inflammation plays a role in both prostate cancer (PCa and benign prostate hyperplasia (BPH. This study evaluates the risk of PC after transurethral resection (TURP for BPH and estimates the PCa risk related to presence of inflammation in the resected material. The Pathology Department at the University Hospital of Umeå (Umeå, Sweden identified BPH cases (n = 7,901 that underwent TURP between 1982 and 1997. Using these pathological specimens, we compared the incidence of PCa in the cohort to the population and calculated the standardized incidence and mortality ratios (SIR and SMR. Inflammation, the androgen receptor (AR, and p53 were evaluated in a nested case-control study of 201 cases and controls. Inflammation was graded severe or mild-moderate. In the follow-up period after TURP, cases developed prostate cancer and the controls did not. After TURP, SIR for prostate cancer increased [1.26, CI 95% (1.17–1.35], whereas SMR decreased [0.59, CI 95% (0.47–0.73]. Presence of inflammation at the time of TURP did not differ between cases and controls nor were there differences in p53 or AR staining. The data suggest a small increased risk of PCa after TURP and decreased PCa mortality. Inflammation at the time of TURP is not associated with PCa risk in this material. The increased PCa risk may be attributed to increased surveillance and PSA screening.

  1. The incidence, risk factors, and outcome of transfusion-related acute lung injury in a cohort of cardiac surgery patients: a prospective nested case-control study.

    NARCIS (Netherlands)

    Vlaar, A.P.J.; Hofstra, J.J.; Determann, R.M.; Veelo, D.P.; Paulus, F.; Kulik, W.; Korevaar, J.; Mol, B.A. de; Koopman, M.M.W.; Porcelijn, L.; Binnekade, J.M.; Vroom, M.B.; Schultz, M.J.; Juffermans, N.P.

    2011-01-01

    Transfusion-related acute lung injury (TRALI) is the leading cause of transfusion-related morbidity and mortality. Both antibodies and bioactive lipids that have accumulated during storage of blood have been implicated in TRALI pathogenesis. In a single-center, nested, case-control study, patients w

  2. Association between pre-diagnostic circulating vitamin D concentration and risk of colorectal cancer in European populations : a nested case-control study

    NARCIS (Netherlands)

    Jenab, Mazda; Bueno-de-Mesquita, H. Bas; Ferrari, Pietro; van Duijnhoven, Franzel J. B.; Norat, Teresa; Pischon, Tobias; Jansen, Eugene H. J. M.; Slimani, Nadia; Byrnes, Graham; Rinaldi, Sabina; Tjonneland, Anne; Olsen, Anja; Overvad, Kim; Boutron-Ruault, Marie-Christine; Clavel-Chapelon, Francoise; Morois, Sophie; Kaaks, Rudolf; Linseisen, Jakob; Boeing, Heiner; Bergmann, Manuela M.; Trichopoulou, Antonia; Misirli, Gesthimani; Trichopoulos, Dimitrios; Berrino, Franco; Vineis, Paolo; Panico, Salvatore; Palli, Domenico; Tumino, Rosario; Ros, Martine M.; van Gils, Carla H.; Peeters, Petra H.; Brustad, Magritt; Lund, Eiliv; Tormo, Maria-Jose; Ardanaz, Eva; Rodriguez, Laudina; Sanchez, Maria-Jose; Dorronsoro, Miren; Gonzalez, Carlos A.; Hallmans, Goeran; Palmqvist, Richard; Roddam, Andrew; Key, Timothy J.; Khaw, Kay-Tee; Autier, Philippe; Hainaut, Pierre; Riboli, Elio

    2010-01-01

    Objective To examine the association between pre-diagnostic circulating vitamin D concentration, dietary intake of vitamin D and calcium, and the risk of colorectal cancer in European populations. Design Nested case-control study. Setting The study was conducted within the EPIC study, a cohort of mo

  3. Circulating C-Reactive Protein Concentrations and Risks of Colon and Rectal Cancer : A Nested Case-Control Study Within the European Prospective Investigation into Cancer and Nutrition

    NARCIS (Netherlands)

    Aleksandrova, Krasimira; Jenab, Mazda; Boeing, Heiner; Jansen, Eugene; Bueno-de-Mesquita, H. Bas; Rinaldi, Sabina; Riboli, Elio; Overvad, Kim; Dahm, Christina C.; Olsen, Anja; Tjonneland, Anne; Boutron-Ruault, Marie-Christine; Clavel-Chapelon, Francoise; Morois, Sophie; Palli, Domenico; Krogh, Vittorio; Tumino, Rosario; Vineis, Paolo; Panico, Salvatore; Kaaks, Rudolf; Rohrmann, Sabine; Trichopoulou, Antonia; Lagiou, Pagona; Trichopoulos, Dimitrios; van Duijnhoven, Fraenzel J. B.; Leufkens, Anke M.; Peeters, Petra H.; Rodriguez, Laudina; Bonet, Catalina; Sanchez, Maria-Jose; Dorronsoro, Miren; Navarro, Carmen; Barricarte, Aurelio; Palmqvist, Richard; Hallmans, Goran; Khaw, Kay-Tee; Wareham, Nicholas; Allen, Naomi E.; Spencer, Elizabeth; Romaguera, Dora; Norat, Teresa; Pischon, Tobias

    2010-01-01

    The authors investigated associations between serum C-reactive protein (CRP) concentrations and colon and rectal cancer risk in a nested case-control study within the European Prospective Investigation into Cancer and Nutrition (1992-2003) among 1,096 incident cases and 1,096 controls selected using

  4. Association between pre-diagnostic circulating vitamin D concentration and risk of colorectal cancer in European populations:a nested case-control study.

    NARCIS (Netherlands)

    Jenab, M.; Bueno De Mesquita, H.B.; Ferrari, P.; Duijnhoven, F.J.B. van; Norat, T.; Pischon, T.; Jansen, E.H.; Slimani, N.; Byrnes, G.; Rinaldi, S.; Tjonneland, A.; Olsen, A.; Overvad, K.; Boutron-Ruault, M.C.; Clavel-Chapelon, F.; Morois, S.; Kaaks, R.; Linseisen, J.; Boeing, H.; Bergmann, M.M.; Trichopoulou, A.; Misirli, G.; Trichopoulos, D.; Berrino, F.; Vineis, P.; Panico, S.; Palli, D.; Tumino, R.; Ros, M.M.; Gils, C.H. van; Peeters, P.H.M.; Brustad, M.; Lund, E.; Tormo, M.J.; Ardanaz, E.; Rodriguez, L.; Sanchez, M.J.; Dorronsoro, M.; Gonzalez, C.A.; Hallmans, G.; Palmqvist, R.; Roddam, A.; Key, T.J.; Khaw, K.T.; Autier, P.; Hainaut, P.; Riboli, E.

    2010-01-01

    OBJECTIVE: To examine the association between pre-diagnostic circulating vitamin D concentration, dietary intake of vitamin D and calcium, and the risk of colorectal cancer in European populations. DESIGN: Nested case-control study. Setting The study was conducted within the EPIC study, a cohort of

  5. Impact of Urate Level on Cardiovascular Risk in Allopurinol Treated Patients. A Nested Case-Control Study.

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    Kasper Søltoft Larsen

    Full Text Available Gout gives rise to increased risk of cardiovascular events. Gout attacks can be effectively prevented with urate lowering drugs, and allopurinol potentially reduces cardiovascular risk. What target level of urate is required to reduce cardiovascular risk is not known.To investigate the effect of achieving target plasma urate with allopurinol on cardiovascular outcomes in a case-control study nested within long-term users of allopurinol.We identified long-term users of allopurinol in Funen County, Denmark. Among these, we identified all cases of cardiovascular events and sampled 4 controls to each case from the same population. The cases and controls were compared with respect to whether they reached a urate target below 0.36 mmol/l on allopurinol. The derived odds ratios were controlled for potential confounders available from data on prescriptions, laboratory values and in- and outpatient contacts.No association between treatment-to-target urate level and cardiovascular events were found (adjusted odds ratio of 1.01, 95% confidence interval 0.79-1.28. No significant effect was seen in any subgroup defined by age, gender, renal function, allopurinol dose or the achieved urate level. Overall, the doses of allopurinol used in this study were low (mean ≈ 140 mg/day.We were unable to demonstrate a link between achieved urate level in patients treated with allopurinol and risk of cardiovascular events. Possible explanations include that allopurinol doses higher than those used in this study are required to achieve cardiovascular risk reduction or that the cardiovascular effect of allopurinol is not mediated through low urate levels. It remains to be seen whether allopurinol has a dose-response relationship with cardiovascular events at higher doses.

  6. Presence of antibodies against Coxiella burnetii and risk of spontaneous abortion: a nested case-control study.

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    Stine Yde Nielsen

    Full Text Available BACKGROUND AND AIMS: Q fever is a bacterial zoonosis caused by infection with Coxiella burnetii. It is well established that Q fever causes fetal loss in small ruminants. The suspicion has been raised that pregnant women may also experience adverse pregnancy outcome when the infection is acquired or reactivated during pregnancy. The purpose of this study was to assess the potential association between serologic markers of infection with C. burnetii and spontaneous abortion. METHODS: A nested case-control study within the Danish National Birth Cohort, a cohort of 100,418 pregnancies recruited from 1996-2002. Women were recruited in first trimester of pregnancy and followed prospectively. Median gestational age at enrolment was 8 weeks (25 and 75 percentiles: 7 weeks; 10 weeks. During pregnancy, a blood sample was collected at gestational week 6-12 and stored in a bio bank. For this study, a case sample of 218 pregnancies was drawn randomly among the pregnancies in the cohort which ended with a miscarriage before 22 gestational weeks, and a reference group of 482 pregnancies was selected in a random fashion among all pregnancies in the cohort. From these pregnancies, serum samples were screened for antibodies against C. burnetii in a commercial enzyme-linked immunosorbent assay (ELISA. Samples that proved IgG or IgM antibody positive were subsequently confirmatory tested by an immunofluorescence (IFA test. RESULTS: Among cases, 11 (5% were C. burnetii positive in ELISA of which one was confirmed in the IFA assay compared to 29 (6% ELISA positive and 3 IFA confirmed in the random sample. CONCLUSIONS: We found no evidence of a higher prevalence of C. burnetii antibodies in serum samples from women who later miscarried and the present study does not indicate a major association between Q fever infection and spontaneous abortion in humans. Very early first trimester abortions were, however, not included in the study.

  7. Diabetes mellitus increases the prevalence of anemia in patients with chronic kidney disease: A nested case-control study

    Science.gov (United States)

    Loutradis, Charalampos; Skodra, Alexandra; Georgianos, Panagiotis; Tolika, Panagiota; Alexandrou, Dimitris; Avdelidou, Afroditi; Sarafidis, Pantelis A

    2016-01-01

    AIM: To compare anemia prevalence between matched chronic kidney disease (CKD) patients with and without diabetes mellitus (DM) and to assess factors associated with anemia development. METHODS: This is a nested case-control study of 184 type-2 diabetic and 184 non-diabetic CKD patients from a prospectively assembled database of a Nephrology outpatient clinic, matched for gender, age and estimated glomerular filtration rate (eGFR). Prevalence of anemia (hemoglobin: Men: recombinant erythropoietin) was examined in comparison, in the total population and by CKD Stage. Univariate and multivariate logistic regression analyses were conducted to identify factors associated with anemia. RESULTS: The total prevalence of anemia was higher in diabetics (47.8% vs 33.2%, P = 0.004). Accordingly, prevalence was higher in diabetics in CKD Stage 3 (53.5% vs 33.1%, P < 0.001) and particularly in Stage 3a (60.4% vs 26.4%, P < 0.001), whereas it was non-significantly higher in Stage 4 (61.3% vs 48.4%; P = 0.307). Serum ferritin was higher in diabetics in total and in CKD stages, while serum iron was similar between groups. In multivariate analyses, DM (OR = 2.206, 95%CI: 1.196-4.069), CKD Stages 3a, 3b, 4 (Stage 4: OR = 12.169, 95%CI: 3.783-39.147) and serum iron (OR = 0.976, 95%CI: 0.968-0.985 per mg/dL increase) were independently associated with anemia. CONCLUSION: Prevalence of anemia progressively increases with advancing stages of CKD and is higher in diabetic than matched non-diabetic CKD patients and diabetes is independently associated with anemia occurrence. Detection and treatment of anemia in diabetic CKD patients should be performed earlier than non-diabetic counterparts. PMID:27458564

  8. Genetic Polymorphisms in Vitamin D Metabolism and Signaling Genes and Risk of Breast Cancer: A Nested Case-Control Study.

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    Tess V Clendenen

    Full Text Available Genetic polymorphisms in vitamin D metabolism and signaling genes have been inconsistently associated with risk of breast cancer, though few studies have examined SNPs in vitamin D-related genes other than the vitamin D receptor (VDR gene and particularly have not examined the association with the retinoid X receptor alpha (RXRA gene which may be a key vitamin D pathway gene. We conducted a nested case-control study of 734 cases and 1435 individually matched controls from a population-based prospective cohort study, the Northern Sweden Mammary Screening Cohort. Tag and functional SNPs were genotyped for the VDR, cytochrome p450 24A1 (CYP24A1, and RXRA genes. We also genotyped specific SNPs in four other genes related to vitamin D metabolism and signaling (GC/VDBP, CYP2R1, DHCR7, and CYP27B1. SNPs in the CYP2R1, DHCR7, and VDBP gene regions that were associated with circulating 25(OHD concentration in GWAS were also associated with plasma 25(OHD in our study (p-trend <0.005. After taking into account the false discovery rate, these SNPs were not significantly associated with breast cancer risk, nor were any of the other SNPs or haplotypes in VDR, RXRA, and CYP24A1. We observed no statistically significant associations between polymorphisms or haplotypes in key vitamin D-related genes and risk of breast cancer. These results, combined with the observation in this cohort and most other prospective studies of no association of circulating 25(OHD with breast cancer risk, do not support an association between vitamin D and breast cancer risk.

  9. Oncogenic CagA promotes gastric cancer risk via activating ERK signaling pathways: a nested case-control study.

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    Jae Jeong Yang

    Full Text Available BACKGROUND: CagA cellular interaction via activation of the ERK signaling pathway may be a starting point in the development of gastric cancer. This study aimed to evaluate whether genes involved in ERK downstream signaling pathways activated by CagA are susceptible genetic markers for gastric cancer. METHODS: In the discovery phase, a total of 580 SNPs within +/-5 kbp of 30 candidate genes were genotyped to examine an association with gastric cancer risk in the Korean Multi-center Cancer Cohort (100 incident gastric cancer case-control sets. The most significant SNPs (raw or permutated p value<0.02 identified in the discovery analysis were re-evaluated in the extension phase using unconditional logistic regression model (400 gastric cancer case-control sets. Combined analyses including pooled- and meta-analysis were conducted to summarize all the results. RESULTS: 24 SNPs in eight genes (ERK, Dock180, C3G, Rap1, Src, CrkL, Mek and Crk were significantly associated with gastric cancer risk in the individual SNP analyses in the discovery phase (p<0.05. In the extension analyses, ERK rs5999749, Dock180 rs4635002 and C3G rs7853122 showed marginally significant gene-dose effects for gastric cancer. Consistently, final combined analysis presented the SNPs as significantly associated with gastric cancer risk (OR = 1.56, [95% CI: 1.19-2.06], OR = 0.61, [95% CI: 0.43-0.87], OR = 0.59, [95% CI: 0.54-0.76], respectively. CONCLUSIONS: Our findings suggest that ERK rs5999749, Dock180 rs4635002 and C3G rs7853122 are genetic determinants in gastric carcinogenesis.

  10. Risk of preterm delivery with increasing depth of excision for cervical intraepithelial neoplasia in England: nested case-control study

    Science.gov (United States)

    Castanon, Alejandra; Landy, Rebecca; Brocklehurst, Peter; Evans, Heather; Peebles, Donald; Singh, Naveena; Walker, Patrick; Patnick, Julietta

    2014-01-01

    Objective To determine the association between depth of excision of cervical intraepithelial neoplasia and risk of preterm birth. Design Case-control study nested in record linkage cohort study. Setting 12 hospitals in England. Participants From a cohort of 11 471 women with at least one histological sample taken at colposcopy and a live singleton birth (before or after colposcopy), 1313 women with a preterm birth (20-36 weeks) were identified and frequency matched on maternal age at delivery, parity, and study site to 1313 women with term births (38-42 weeks). Main outcome measures Risk of preterm birth and very/extreme preterm birth by depth of excisional treatment of the cervical transformation zone. Results After exclusions, 768 preterm births (cases) and 830 term births after colposcopy remained. The risk of preterm birth was no greater in women with a previous small (<10 mm) excision (absolute risk 7.5%, 95% confidence interval 6.0% to 8.9%) than in women with a diagnostic punch biopsy (7.2%, 5.9% to 8.5%). Women with a medium (10-14 mm) (absolute risk 9.6%; relative risk 1.28, 0.98 to 1.68), large (15-19 mm) (15.3%; 2.04, 1.41 to 2.96), or very large (≥20 mm) excision (18.0%; 2.40, 1.53 to 3.75) had a higher risk of preterm delivery than those with small excision. The same pattern was seen in 161 women with very/extremely preterm births (20-31 weeks) and with increasing volume excised. Most births were conceived more than three years after colposcopy, and the risk of preterm delivery did not seem to depend on time from excision to conception. Conclusions The risk of preterm birth is at most minimally affected by a small excision. Larger excisions, particularly over 15 mm or 2.66 cm3, are associated with a doubling of the risk of both preterm and very preterm births. The risk does not decrease with increasing time from excision to conception. Efforts should be made to excise the entire lesion while preserving as much healthy cervical tissue as possible

  11. Cancer and frailty in older adults: a nested case-control study of the Mexican Health and Aging Study

    Science.gov (United States)

    Pérez-Zepeda, Mario Ulises; Cárdenas-Cárdenas, Eduardo; Cesari, Matteo; Navarrete-Reyes, Ana Patricia; Gutiérrez-Robledo, Luis Miguel

    2016-01-01

    Purpose Understanding how the convergence between chronic and complex diseases—such as cancer—and emerging conditions of older adults—such as frailty—takes place would help in halting the path that leads to disability in this age group. The objective of this manuscript is to describe the association between a past medical history of cancer and frailty in Mexican older adults. Methods This is a nested in cohort case-control study of the Mexican Health and Aging Study. Frailty was categorized by developing a 55-item frailty index that was also used to define cases in two ways: incident frailty (incident >0.25 frailty index score) and worsening frailty (negative residuals from a regression between 2001 and 2012 frailty index scores). Exposition was defined as self-report of cancer between 2001 and 2012. Older adults with a cancer history were further divided into recently diagnosed (10 years from the initial diagnosis). Odds ratios were estimated by fitting a logistic regression adjusted for confounding variables. Results Out of a total of 8022 older adults with a mean age of 70.6 years, the prevalence of a past medical history of cancer was 3.6 % (n = 288). Among these participants, 45.1 % had been diagnosed with cancer more than 10 years previously. A higher risk of incident frailty compared to controls [odds ratio (OR) 1.53 (95 % confidence interval (CI) 1.04–2.26, p = 0.03); adjusted model OR 1.74 (95 % CI 1.15–2.61, p = 0.008)] was found in the group with a recent cancer diagnosis. Also, an inverse association between a remote cancer diagnosis and worsening frailty was found [OR = 0.56 (95 % CI 0.39–0.8), p = 0.002; adjusted model OR 0.61 (95 % CI 0.38–0.99, p = 0.046)]. Conclusions Cancer is associated with a higher frailty index, with a potential relevant role of the time that has elapsed since the cancer diagnosis. Implications for cancer survivors Cancer survivors may be more likely to develop frailty or worsening of the health status at an

  12. Seroprevalence of Cutaneous Human Papillomaviruses and the Risk of External Genital Lesions in Men: A Nested Case-Control Study

    Science.gov (United States)

    Rahman, Shams; Rollison, Dana E.; Pierce Campbell, Christine M.; Waterboer, Tim; Michel, Angelika; Pawlita, Michael; Villa, Luisa L.; Lazcano Ponce, Eduardo; Wang, Wei; Borenstein, Amy R.; Giuliano, Anna R.

    2016-01-01

    Background A variety of cutaneous human papillomaviruses (HPV) are detectable in genital epithelial lesions in men and non-melanoma skin cancer patients. It remains unclear whether these viruses are associated causally with skin lesions. To date, no study has prospectively examined the association between cutaneous HPV seropositivity and development of external genital lesions (EGLs) in men. Objectives To examine the association between seropositivity to cutaneous HPV types and the risk of subsequent development of EGLs. Methods A nested case-control study including 163 incident EGL cases and 352 EGL-free controls in the HPV Infection in Men (HIM) Study cohort was conducted. Cases were ascertained at each of up to 10 biannual clinical visits and verified through biopsy and pathological diagnoses. EGLs were categorized as condyloma, suggestive of condyloma, penile intraepithelial neoplasia (PeIN), and other EGLs. Archived serum specimens collected at baseline were tested for antibodies against 14 cutaneous HPV types (β types (5, 8, 12, 14, 17, 22, 23, 24, 38, and 47), α type 27, γ type 4, μ type 1, and ν type 41) using a GST L1-based multiplex serology assay. Socio-demographic and sexual behavior data were collected through a questionnaire. Using logistic regression, adjusted odds ratios (AOR) and 95% confidence intervals (CI) were estimated. Results Overall, seropositivity to ≥1 cutaneous HPV type (any-HPV) and ≥1 β types (any-β) was 58.3% and 37.5% among other EGL cases, 71.6% and 46.8% among condyloma, 66.8% and 50.0% among PeIN, and 71.9% and 38.4% among controls, respectively. Type-specific seropositivity was most common for ɤ-HPV 4, μ-HPV 1, and β-HPV 8. No statistically significant association was observed between any-HPV, any-β, and type-specific HPV seropositivity and subsequent development of EGLs across all pathological diagnoses. Conclusions Overall, seropositivity to cutaneous HPV was common among men; however, it appears that cutaneous

  13. Boolean nested canalizing functions: a comprehensive analysis

    CERN Document Server

    Li, Yuan; Murrugarra, David; Aguilar, Boris; Laubenbacher, Reinhard

    2012-01-01

    Boolean network models of molecular regulatory networks have been used successfully in computational systems biology. The Boolean functions that appear in published models tend to have special properties, in particular the property of being nested canalizing, a property inspired by the concept of canalization in evolutionary biology. It has been shown that networks comprised of nested canalizing functions have dynamic properties that make them suitable for modeling molecular regulatory networks, namely a small number of (large) attractors, as well as relatively short limit cycles. This paper contains a detailed analysis of this class of functions, based on a novel normal form as polynomial functions over the Boolean field. The concept of layer is introduced that stratifies variables into different classes depending on their level of dominance. Using this layer concept a closed form formula is derived for the number of nested canalizing functions with a given number of variables. Additional metrics analyzed in...

  14. Delirium and high fever are associated with subacute motor deterioration in Parkinson disease: a nested case-control study.

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    Atsushi Umemura

    Full Text Available BACKGROUND: In Parkinson disease (PD, systemic inflammation caused by respiratory infections such as pneumonia frequently occurs, often resulting in delirium in the advanced stages of this disease. Delirium can lead to cognitive and functional decline, institutionalization, and mortality, especially in the elderly. Inflammation causes rapid worsening of PD motor symptoms and signs, sometimes irreversibly in some, but not all, patients. PURPOSE: To identify factors associated with subacute motor deterioration in PD patients with systemic inflammation. METHODS: The association of clinical factors with subacute motor deterioration was analyzed by a case-control study. Subacute motor deterioration was defined as sustained worsening by one or more modified Hoehn and Yahr (H-Y stages. Using multivariable logistic regression incorporating baseline characteristics (age, sex, PD duration, modified H-Y stage, dementia, and psychosis history and statistically selected possible predictors (peak body temperature, duration of leukocytosis, and presence of delirium, the odds ratios for these factors were estimated as relative risks. RESULTS: Of 80 PD patients with systemic inflammation, 26 with associated subacute motor deterioration were designated as cases and the remainder as controls. In the 26 cases, 6 months after its onset the motor deterioration had persisted in 19 patients and resolved in four (three were lost for follow-up. Multivariable logistic regression analysis showed that delirium and body temperature are significantly associated with motor deterioration after systemic inflammation (P = 0.001 for delirium and P = 0.026 for body temperature, the adjusted odds ratios being 15.89 (95% confidence interval [CI]: 3.23-78.14 and 2.78 (95% CI: 1.13-6.83, respectively. CONCLUSIONS: In patients with PD and systemic inflammation, delirium and high body temperature are strong risk factors for subsequent subacute motor deterioration and such deterioration

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

    Science.gov (United States)

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

    2015-01-01

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

  16. Efficacy of PIVKA-II in prediction and early detection of hepatocellular carcinoma: a nested case-control study in Chinese patients

    OpenAIRE

    Rentao Yu; Xiaomei Xiang; Zhaoxia Tan; Yi Zhou; Haoliang Wang; Guohong Deng

    2016-01-01

    Prognosis of hepatocellular carcinoma (HCC) remains unsatisfying due to a lack of early detecting methods. Protein Induced by Vitamin K Absence or Antagonist-II (PIVKA-II) has been proved to be an efficient biomarker for HCC. However, the predicting efficacy of PIVKA-II has barely been reported. In the Hepatitis Biobank of Southwest Hospital (HBS) cohort at Southwest Hospital, we did a two-stage nested case-control study. Totally, 45 HCC cases versus 138 matched controls were enrolled to comp...

  17. Innate immunity and non-Hodgkin's lymphoma (NHL related genes in a nested case-control study for gastric cancer risk.

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    Sue K Park

    Full Text Available OBJECTIVE: Genetic variants regulating the host immune system may contribute to the susceptibility for the development of gastric cancer. Little is known about the role of the innate immunity- and non-Hodgkin's lymphoma (NHL-related genes for gastric cancer risk. This nested case-control study was conducted to identify candidate genes for gastric cancer risk for future studies. METHODS: In the Discovery phase, 3,072 SNPs in 203 innate immunity- and 264 NHL-related genes using the Illumine GoldenGateTM OPA Panel were analyzed in 42 matched case-control sets selected from the Korean Multi-center Cancer Cohort (KMCC. Six significant SNPs in four innate immunity (DEFA6, DEFB1, JAK3, and ACAA1 and 11 SNPs in nine NHL-related genes (INSL3, CHMP7, BCL2L11, TNFRSF8, RAD50, CASP7, CHUK, CD79B, and CLDN9 with a permutated p-value <0.01 were re-genotyped in the Replication phase among 386 cases and 348 controls. Odds ratios (ORs for gastric cancer risk were estimated adjusting for age, smoking status, and H. pylori and CagA sero-positivity. Summarized ORs in the total study population (428 cases and 390 controls are presented using pooled- and meta-analyses. RESULTS: Four SNPS had no heterogeneity across the phases: in the meta-analysis, DEFA6 rs13275170 and DEFB1 rs2738169 had both a 1.3-fold increased odds ratio (OR for gastric cancer (95% CIs = 1.1-1.6; and 1.1-1.5, respectively. INSL3 rs10421916 and rs11088680 had both a 0.8-fold decreased OR for gastric cancer (95% CIs = 0.7-0.97; and 0.7-0.9, respectively. CONCLUSIONS: Our findings suggest that certain variants in the innate immunity and NHL-related genes affect the gastric cancer risk, perhaps by modulating infection-inflammation-immunity mechanisms that remain to be defined.

  18. Beta-Blockers, Trimethoprim-Sulfamethoxazole, and the Risk of Hyperkalemia Requiring Hospitalization in the Elderly: A Nested Case-Control Study

    Science.gov (United States)

    Weir, Matthew A.; Juurlink, David N.; Gomes, Tara; Mamdani, Muhammad; Hackam, Daniel G.; Jain, Arsh K.

    2010-01-01

    Background and objectives: The simultaneous use of beta adrenergic receptor blockers (β-blockers) and trimethoprim-sulfamethoxazole (TMP-SMX) may confer a high risk of hyperkalemia. Design, setting, participants, & measurements: Two nested case-control studies were conducted to examine the association between hospitalization for hyperkalemia and the use of TMP-SMX in older patients receiving β-blockers. Linked health administrative records from Ontario, Canada, were used to assemble a cohort of 299,749 β-blockers users, aged 66 years or older and capture data regarding medication use and hospital admissions for hyperkalemia. Results: Over the study period from 1994 to 2008, 189 patients in this cohort were hospitalized for hyperkalemia within 14 days of receiving a study antibiotic. Compared with amoxicillin, the use of TMP-SMX was associated with a substantially greater risk of hyperkalemia requiring hospital admission (adjusted odds ratio, 5.1; 95% confidence interval [CI], 2.8 to 9.4). No such risk was identified with ciprofloxacin, norfloxacin, or nitrofurantoin. When dosing was considered, the association was greater at higher doses of TMP-SMX. When the primary analysis was repeated in a cohort of non-β-blocker users, the risk of hyperkalemia comparing TMP-SMX to amoxicillin was not significantly different from that found among β-blocker users. Conclusions: Although TMP-SMX is associated with an increased risk of hyperkalemia in older adults, these findings show no added risk when used in combination with β-blockers. PMID:20595693

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

    Science.gov (United States)

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

    2016-01-01

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

  20. Organochlorine exposures influence on breast cancer risk and survival according to estrogen receptor status: a Danish cohort-nested case-control study

    Directory of Open Access Journals (Sweden)

    Rank Fritz

    2001-07-01

    Full Text Available Abstract Background The relationship between breast cancer and organochlorine exposure is controversial and complex. As estrogen receptor positive and negative breast cancer may represent different entities of the disease, this study was undertaken to evaluate organochlorines influence on breast cancer risk and survival according to receptor status. Methods The background material stems from the Copenhagen City Heart Study (Denmark 1976-78. The breast cancer risk was investigated in a cohort nested case-control design including 161 cases and twice as many breast cancer free controls. The cases served as a cohort in the survival analysis. Serum organochlorine concentrations were determined by gaschromotography. Results The observed increased breast cancer risk associated with exposure to dieldrin derived from women who developed an estrogen receptor negative (ERN tumor (Odds ratio [OR] I vs. IV quartile, 7.6, 95% confidence interval [95% CI] 1.4-46.1, p-value for linear trend 0.01. Tumors in women with the highest dieldrin serum level were larger and more often spread at the time of diagnosis than ERP tumors. The risk of dying was for the remaining evaluated compounds higher among patients with ERP breast cancer when compared to those with ERN. In the highest quartile of polychlorinated biphenyls (ΣPCB it was more than 2-fold increased (Relative risk [RR] I vs. IV quartile, 2.5, 95% CI 1.1-5.7, but no dose-response relation was apparent. Conclusion The results do not suggest that exposure to potential estrogenic organochlorines leads to development of an ERP breast cancer. A possible adverse effect on prognosis of hormone-responsive breast cancers needs to be clarified.

  1. Selective chromosome analysis in couples with two or more miscarriages : case-control study

    NARCIS (Netherlands)

    Franssen, MTM; Korevaar, JC; Leschot, NJ; Bossuyt, PMM; Knegt, AC; Gerssen-Schoorl, KBJ; Wouters, CH; Hansson, KBM; Hochstenbach, R; Madan, K; van der Veen, F; Goddijn, M

    2005-01-01

    Objective To identify additional factors, such as maternal age or factors related to previous reproductive outcome or family history, and the corresponding probability of carrying a chromosome abnormality in couples with two or more miscarriages. Design Nested case-control study. Setting Six centres

  2. Effect of consanguinity on birth defects in Saudi women; results from a nested case-control study

    DEFF Research Database (Denmark)

    Majeed-Saidan, Muhammad Ali; Ammari, Amer N; AlHashem, Amal M;

    2015-01-01

    : This case and control study was nested within a 3-year prospective cohort study to examine patterns of fetal and neonatal malformations in Saudi women at Prince Sultan Military Medical City (PSMMC), Riyadh -Saudi Arabia. Consanguineous marriages were defined as marriages with first or second cousins......BACKGROUND: The role of consanguinity in the etiology of structural birth defects outside of chromosomal and inherited disorders has always been debated. We studied the independent role of consanguinity on birth defects in Saudi women with a high prevalence of consanguineous marriages. METHODS...

  3. Case-control analysis of paternal age and trisomic anomalies

    NARCIS (Netherlands)

    De Souza, E.; Morris, Joan K.

    2010-01-01

    Objectives To determine whether older paternal age increases the risk of fathering a pregnancy with Patau (trisomy 13), Edwards (trisomy 18), Klinefelter (XXY) or XYY syndrome. Design Case-control: cases with each of these syndromes were matched to four controls with Down syndrome from within the sa

  4. Young people's risk of suicide attempts after contact with a psychiatric department - a nested case-control design using Danish register data

    DEFF Research Database (Denmark)

    Christiansen, Erik; Juul Larsen, Kim

    2012-01-01

    Background:  There seems to be an increased risk of children and adolescents committing or attempting suicide after contact with a psychiatric department. Children and adolescents living in families with low socio-economic status (SES) might have an especially increased suicide attempt risk...... discharge from last contact with a psychiatric department. The risk of suicide attempt is highest for children and adolescents suffering from personality disorders, depression and substance use disorders. Children and adolescents with previous contact with a psychiatric department and parental income....... Methods:  A complete extraction of Danish register data for every individual born in the period 1983-1989 was made. Of these 403,431 individuals, 3,465 had attempted suicide. In order to control for confounder effects from gender, age and calendar-time, a nested case-control study was designed. A total...

  5. Atopy and new-onset asthma in young Danish farmers and CD14, TLR2, and TLR4 genetic polymorphisms: a nested case-control study

    DEFF Research Database (Denmark)

    Smit, L A M; Bongers, S I M; Ruven, H J T;

    2007-01-01

    BACKGROUND: Evidence exists that exposure to high levels of microbial agents such as endotoxin in the farm environment decreases the risk of atopic sensitization. Genetic variation in innate immunity genes may modulate the response to microbial agents and thus influence susceptibility to asthma...... and atopy. OBJECTIVE: To study potential associations between single nucleotide polymorphisms (SNPs) in CD14, Toll-like receptor 2 (TLR2), and TLR4 genes, and atopy and new-onset asthma in young farmers. METHODS: A nested case-control study was conducted within a cohort of 1901 young Danish farmers. We....../-651 promoter polymorphisms are associated with atopy prevalence among young adults exposed to farm environments. Udgivelsesdato: 2007-Nov...

  6. Tissue-type plasminogen activator and C-reactive protein in acute coronary heart disease. A nested case-control study

    DEFF Research Database (Denmark)

    Gram, J; Bladbjerg, E-M; Møller, L

    2000-01-01

    OBJECTIVES: To study the importance of inflammation and fibrinolysis for evolution of ischaemic heart disease in a cohort of initially healthy subjects. DESIGN: Nested case-control study. Follow-up periods 7-15 years. SUBJECTS: Included in the study were 133 cases with coronary heart disease...... and 258 controls. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Subjects with ischaemic heart disease identified in 1991 by the Danish National Hospital Register. Protein concentration of C-reactive protein (CRP) and tissue-type plasminogen activator (t-PA) were measured with ELISA methods in stored serum...... samples. RESULTS: CRP and t-PA concentrations were both significantly higher in cases than in controls (P difference between cases and controls for CRP and t-PA was present in both men (CRP: P = 0.022; t-PA: P = 0.001) and women (CRP: P = 0.013; t-PA: P = 0...

  7. Insulin-like growth factor-related components and the risk of liver cancer in a nested case-control study.

    Science.gov (United States)

    Adachi, Yasushi; Nojima, Masanori; Mori, Mitsuru; Matsunaga, Yasutaka; Akutsu, Noriyuki; Sasaki, Shigeru; Endo, Takao; Kurozawa, Youichi; Wakai, Kenji; Tamakoshi, Akiko

    2016-11-01

    Insulin-like growth factor-1 (IGF1) is a potent mitogen. IGF-binding protein-3 (IGFBP3) binds and inhibits IGF1. High circulating IGF1 levels and low IGFBP3 levels are associated with increased risk of several cancers. We examined relationships between serum levels of these factors and hepatoma risk in a case-control study nested in a prospective cohort study (the Japan Collaborative Cohort Study (JACC Study)). A baseline survey was conducted from 1988 to 1990, and 39,242 subjects donated blood samples. Participants diagnosed with hepatoma by 1997 were considered cases for nested case-control studies. Ninety-one cases and 263 sex- and age-matched controls were analyzed. A conditional logistic model was used to estimate odds ratios (ORs) for the incidence of hepatoma associated with serum IGF1 and IGFBP3 levels. Neither IGF1 nor the molar ratio of IGF1/IGFBP3 was correlated with hepatoma risk. After adjustment for hepatitis viral infection, body mass index, smoking, and alcohol intake, a higher molar difference of (IGFBP3 - IGF1) was associated with a decreased hepatoma risk more than IGFBP3 alone (p for trend <0.001 and = 0.003, respectively). People in the highest quartile had a lower risk (OR = 0.098; 95 % confidence interval = 0.026-0.368). In subgroup analyses of males and females, the molar difference was associated with a decreased hepatoma risk (p for trend <0.05). In non-elderly individuals, the difference was inversely correlated with the incidence of hepatoma (p for trend <0.01). The molar difference of (IGFBP3 - IGF1) may be inversely associated with the incidence of hepatoma.

  8. The relationship between weight gain during pregnancy and urinary tract infections in pregnant women of Shahrekord, by using the “Nested case-control study”, in 2013

    Science.gov (United States)

    Rejali, Mehri; Ahmadi, Seyede Soghra; Hassanzadeh, Akbar; Yazdani, Rezvan; Ahmadi, Seyede Nafiseh

    2015-01-01

    Background and Objectives: Pregnancy is one of the most important and risky periods in mothers and the fetus life, which plays a key role in health and social activity of the person, family and community. This study is trying to see if there is a relation between increasing weight and urinary tract infection (UTI) in pregnancy by using the open nested case-control study in the city of Shahrekord. Materials and Methods: In a nested case-control study, one cohort including 832 patients was examined until week 26 to 30 of pregnancy and their UTIs were studied. The required information was collected by examining the health records of pregnant women and completion of the data registration forms. Data collection was controlled by using SPSS and analyzed by using an independent t-test, Chi-square test, Pearson correlation and logistic regression. Results: According to the results of the cohort study with 832 individuals, average weight gain of the group with a UTI was 11.13 ± 3.9 kg and it was 10.63 ± 3.9 kg in the group without UTI, showing no statistically significant difference (P = 0.245). According to the results, genitourinary problems had the highest predictive value for UTIs and the numbers of infertility and the childbirth variables were in the second and third positions, respectively. Conclusion: According to the results study we can conclude that screening and treatment of UTIs have been on time and appropriate in health systems of the city of Shahrekord which have lead to the reduction of infant and maternal diseases even with the condition in having no UTI, and continuing this process for screening and treatment is recommended. PMID:27462626

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

    Energy Technology Data Exchange (ETDEWEB)

    Tukenova, Markhaba; Diallo, Ibrahima [Radiation Epidemiology Group, CESP Center for Research in Epidemiology and Population Health, INSERM, Villejuif (France); University Paris Sud 11, UMRS, Villejuif (France); Gustave Roussy Institute, Villejuif (France); Anderson, Harald [Department of Cancer Epidemiology, Lund University, Lund (Sweden); Hawkins, Mike [Center for Childhood Cancer Survivor Studies, Department of Public Health and Epidemiology, University of Birmingham, Birmingham (United Kingdom); Garwicz, Stanislaw [Childhood Cancer Research Center, University Children' s Hospital, Lund (Sweden); Sankila, Risto [Finnish Cancer Registry, Helsinki (Finland); El Fayech, Chiraz [Radiation Epidemiology Group, CESP Center for Research in Epidemiology and Population Health, INSERM, Villejuif (France); University Paris Sud 11, UMRS, Villejuif (France); Gustave Roussy Institute, Villejuif (France); Winter, Dave [Center for Childhood Cancer Survivor Studies, Department of Public Health and Epidemiology, University of Birmingham, Birmingham (United Kingdom); Rubino, Carole [Radiation Epidemiology Group, CESP Center for Research in Epidemiology and Population Health, INSERM, Villejuif (France); University Paris Sud 11, UMRS, Villejuif (France); Gustave Roussy Institute, Villejuif (France); Adjadj, Elisabeth [Radiation Epidemiology Group, CESP Center for Research in Epidemiology and Population Health, INSERM, Villejuif (France); University Paris Sud 11, UMRS, Villejuif (France); Gustave Roussy Institute, Villejuif (France); Curie Institute, Paris (France); Haddy, Nadia; Oberlin, Odile [Radiation Epidemiology Group, CESP Center for Research in Epidemiology and Population Health, INSERM, Villejuif (France); University Paris Sud 11, UMRS, Villejuif (France); Gustave Roussy Institute, Villejuif (France); Moller, Torgil [Department of Cancer Epidemiology, Lund University, Lund (Sweden); Langmark, Froydis [Finnish Cancer Registry, Helsinki (Finland); and others

    2012-03-01

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

  10. External validation of a COPD prediction model using population-based primary care data: a nested case-control study

    Science.gov (United States)

    Nwaru, Bright I; Simpson, Colin R; Sheikh, Aziz; Kotz, Daniel

    2017-01-01

    Emerging models for predicting risk of chronic obstructive pulmonary disease (COPD) require external validation in order to assess their clinical value. We validated a previous model for predicting new onset COPD in a different database. We randomly drew 38,597 case-control pairs (total N = 77,194) of individuals aged ≥35 years and matched for sex, age, and general practice from the United Kingdom Clinical Practice Research Datalink database. We assessed accuracy of the model to discriminate between COPD cases and non-cases by calculating area under the receiver operator characteristic (ROCAUC) for the prediction scores. Analogous to the development model, ever smoking (OR 6.70; 95%CI 6.41–6.99), prior asthma (OR 6.43; 95%CI 5.85–7.07), and higher socioeconomic deprivation (OR 2.90; 95%CI 2.72–3.09 for highest vs. lowest quintile) increased the risk of COPD. The validated prediction scores ranged from 0–5.71 (ROCAUC 0.66; 95%CI 0.65–0.66) for males and 0–5.95 (ROCAUC 0.71; 95%CI 0.70–0.71) for females. We have confirmed that smoking, prior asthma, and socioeconomic deprivation are key risk factors for new onset COPD. Our model seems externally valid at identifying patients at risk of developing COPD. An impact assessment now needs to be undertaken to assess whether this prediction model can be applied in clinical care settings. PMID:28304375

  11. Semantic Analysis of Virtual Classes and Nested Classes

    DEFF Research Database (Denmark)

    Madsen, Ole Lehrmann

    1999-01-01

    Virtual classes and nested classes are distinguishing features of BETA. Nested classes originated from Simula, but until recently they have not been part of main stream object- oriented languages. C++ has a restricted form of nested classes and they were included in Java 1.1. Virtual classes...... the central elements of the semantic analysis used in the Mjølner BETA compiler....

  12. Low-density lipoprotein cholesterol is associated with fracture risk in diabetes patients - a nested case-control study

    DEFF Research Database (Denmark)

    Starup-Linde, Jakob; Gregersen, Søren; Vestergaard, Peter

    2014-01-01

    available for an analysis of patient characteristics, co-morbidities, biochemical parameters and drug usage. Results: Patient age at the time of diabetes diagnosis, a diagnosis of previous fracture, an alcohol related diagnosis, total cholesterol level, and the usage of antidepressants, antiepileptics...... and insulin all increased the odds of fracture. Low-density lipoprotein cholesterol (LDL) levels decreased the odds of fracture, where the level of 3.04-5.96 mmol/l was optimal with regard to fracture risk. Conclusion: LDL may add to the understanding of fractures in diabetes patients and it may be added...

  13. Association of Serum Magnesium Level with Odds of Prediabetes and Diabetes in a Southern Chinese Population: a Prospective Nested Case-Control Study.

    Science.gov (United States)

    Fang, Chenchen; Wang, Xuebao; Wu, Wenjun; Gu, Xuejiang; Ye, Tingting; Deng, Huihui; Wang, Xianqin; Shen, Feixia

    2016-08-01

    Although emerging clinical evidence supports that magnesium deficiency is a risk factor for the development of type 2 diabetes, there are sparse studies concerning the dynamic change of serum magnesium with the risk of diabetes and its early stages. In this nested case-control study, we performed a 75-g oral glucose tolerance test or a standardized steamed bread meal test in 178 subjects with incident glucose metabolism impairment (33 with type 2 diabetes and 145 with prediabetes) and 178 matched controls at baseline and at 3-year follow-up and determined the associations between baseline serum magnesium levels as well as changes in serum magnesium levels at follow-up and odds of prediabetes and diabetes. After adjusting for potential confounders, the odds ratios of risk for prediabetes and type 2 diabetes in the highest quartile of serum magnesium levels were 0.22 (95 % confidence intervals [CI] 0.10-0.49; p for trend magnesium level was detected in type 2 diabetes cases (p = 0.015) at 3 years as compared with at baseline. These results suggest that a low magnesium level is an independent risk factor for prediabetes and type 2 diabetes, and that the reduction of serum magnesium is associated with type 2 diabetes in a southern Chinese population.

  14. Trends in Kaposi's sarcoma-associated Herpesvirus antibodies prior to the development of HIV-associated Kaposi's sarcoma: A nested case-control study

    Science.gov (United States)

    Wakeham, Katie; Johnston, W Thomas; Nalwoga, Angela; Webb, Emily L; Mayanja, Billy N; Miley, Wendell; Elliott, Alison M; Whitby, Denise; Newton, Robert

    2015-01-01

    HIV-associated Kaposi's sarcoma (KS) is a public health challenge in sub-Saharan Africa since both the causative agent, Kaposi's sarcoma associated-herpesvirus (KSHV), and the major risk factor, HIV, are prevalent. In a nested case-control study within a long-standing clinical cohort in rural Uganda, we used stored sera to examine the evolution of antibody titres against the KSHV antigens K8.1 and latency-associated nuclear antigen (LANA) among 30 HIV-infected subjects who subsequently developed HIV-related KS (cases) and among 108 matched HIV/KSHV coinfected controls who did not develop KS. Throughout the 6 years prior to diagnosis, antibody titres to K8.1 and LANA were significantly higher among cases than controls (p < 0.0001), and titres increased prior to diagnosis in the cases. K8.1 titres differed more between KS cases and controls, compared to LANA titres. These differences in titre between cases and controls suggest a role for lytic viral replication in the pathogenesis of HIV-related KS in this setting. PMID:25395177

  15. Use of non-steroidal anti-inflammatory drugs and prostate cancer risk: a population-based nested case-control study.

    Directory of Open Access Journals (Sweden)

    Salaheddin M Mahmud

    Full Text Available BACKGROUND: Despite strong laboratory evidence that non-steroidal anti-inflammatory drugs (NSAIDs could prevent prostate cancer, epidemiological studies have so far reported conflicting results. Most studies were limited by lack of information on dosage and duration of use of the different classes of NSAIDs. METHODS: We conducted a nested case-control study using data from Saskatchewan Prescription Drug Plan (SPDP and Cancer Registry to examine the effects of dose and duration of use of five classes of NSAIDs on prostate cancer risk. Cases (N = 9,007 were men aged ≥40 years diagnosed with prostatic carcinoma between 1985 and 2000, and were matched to four controls on age and duration of SPDP membership. Detailed histories of exposure to prescription NSAIDs and other drugs were obtained from the SPDP. RESULTS: Any use of propionates (e.g., ibuprofen, naproxen was associated with a modest reduction in prostate cancer risk (Odds ratio = 0.90; 95%CI 0.84-0.95, whereas use of other NSAIDs was not. In particular, we did not observe the hypothesized inverse association with aspirin use (1.01; 0.95-1.07. There was no clear evidence of dose-response or duration-response relationships for any of the examined NSAID classes. CONCLUSIONS: Our findings suggest modest benefits of at least some NSAIDs in reducing prostate cancer risk.

  16. Circulating C-reactive protein concentrations and risks of colon and rectal cancer: a nested case-control study within the European Prospective Investigation into Cancer and Nutrition.

    Science.gov (United States)

    Aleksandrova, Krasimira; Jenab, Mazda; Boeing, Heiner; Jansen, Eugene; Bueno-de-Mesquita, H Bas; Rinaldi, Sabina; Riboli, Elio; Overvad, Kim; Dahm, Christina C; Olsen, Anja; Tjønneland, Anne; Boutron-Ruault, Marie-Christine; Clavel-Chapelon, Françoise; Morois, Sophie; Palli, Domenico; Krogh, Vittorio; Tumino, Rosario; Vineis, Paolo; Panico, Salvatore; Kaaks, Rudolf; Rohrmann, Sabine; Trichopoulou, Antonia; Lagiou, Pagona; Trichopoulos, Dimitrios; van Duijnhoven, Fränzel J B; Leufkens, Anke M; Peeters, Petra H; Rodríguez, Laudina; Bonet, Catalina; Sánchez, María-José; Dorronsoro, Miren; Navarro, Carmen; Barricarte, Aurelio; Palmqvist, Richard; Hallmans, Göran; Khaw, Kay-Tee; Wareham, Nicholas; Allen, Naomi E; Spencer, Elizabeth; Romaguera, Dora; Norat, Teresa; Pischon, Tobias

    2010-08-15

    The authors investigated associations between serum C-reactive protein (CRP) concentrations and colon and rectal cancer risk in a nested case-control study within the European Prospective Investigation into Cancer and Nutrition (1992-2003) among 1,096 incident cases and 1,096 controls selected using risk-set sampling and matched on study center, age, sex, time of blood collection, fasting status, menopausal status, menstrual cycle phase, and hormone replacement therapy. In conditional logistic regression with adjustment for education, smoking, nutritional factors, body mass index, and waist circumference, CRP showed a significant nonlinear association with colon cancer risk but not rectal cancer risk. Multivariable-adjusted relative risks for CRP concentrations of > or = 3.0 mg/L versus colon cancer and 1.02 (95% CI: 0.67, 1.57; P-trend = 0.65) for rectal cancer. Colon cancer risk was significantly increased in men (relative risk = 1.74, 95% CI: 1.11, 2.73; P-trend = 0.01) but not in women (relative risk = 1.06, 95% CI: 0.67, 1.68; P-trend = 0.13). Additional adjustment for C-peptide, glycated hemoglobin, and high density lipoprotein cholesterol did not attenuate these results. These data provide evidence that elevated CRP concentrations are related to a higher risk of colon cancer but not rectal cancer, predominantly among men and independently of obesity, insulin resistance, and dyslipidemia.

  17. Does a more refined assessment of exposure to bitumen fume and confounders alter risk estimates from a nested case-control study of lung cancer among European asphalt workers?

    DEFF Research Database (Denmark)

    Agostini, Michela; Ferro, Gilles; Burstyn, Igor

    2013-01-01

    To investigate whether a refined assessment of exposure to bitumen fume among workers in the European asphalt industry within a nested case-control study resulted in a different interpretation pertaining to risk of lung cancer mortality compared with the cohort study....

  18. Spatial analysis of childhood cancer: a case/control study.

    Directory of Open Access Journals (Sweden)

    Rebeca Ramis

    Full Text Available Childhood cancer was the leading cause of death among children aged 1-14 years for 2012 in Spain. Leukemia has the highest incidence, followed by tumors of the central nervous system (CNS and lymphomas (Hodgkin lymphoma, HL, and Non-Hodgkin's lymphoma, NHL. Spatial distribution of childhood cancer cases has been under concern with the aim of identifying potential risk factors.The two objectives are to study overall spatial clustering and cluster detection of cases of the three main childhood cancer causes, looking to increase etiological knowledge.We ran a case-control study. The cases were children aged 0 to 14 diagnosed with leukemia, lymphomas (HL and NHL or CNS neoplasm in five Spanish regions for the period 1996-2011. As a control group, we used a sample from the Birth Registry matching every case by year of birth, autonomous region of residence and sex with six controls. We geocoded and validated the address of the cases and controls. For our two objectives we used two different methodologies. For the first, for overall spatial clustering detection, we used the differences of K functions from the spatial point patterns perspective proposed by Diggle and Chetwynd and the second, for cluster detection, we used the spatial scan statistic proposed by Kulldorff with a level for statistical significance of 0.05.We had 1062 cases of leukemia, 714 cases of CNS, 92 of HL and 246 of NHL. Accordingly we had 6 times the number of controls, 6372 controls for leukemia, 4284 controls for CNS, 552 controls for HL and 1476 controls for NHL. We found variations in the estimated empirical D(s for the different regions and cancers, including some overall spatial clustering for specific regions and distances. We did not find statistically significant clusters.The variations in the estimated empirical D(s for the different regions and cancers could be partially explained by the differences in the spatial distribution of the population; however, according to the

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

    Science.gov (United States)

    Coupland, Carol; Hippisley-Cox, Julia

    2015-01-01

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

  20. Polymorphism in xenobiotic and estrogen metabolizing genes, exposure to perfluorinated compounds and subsequent breast cancer risk: A nested case-control study in the Danish National Birth Cohort.

    Science.gov (United States)

    Ghisari, Mandana; Long, Manhai; Røge, Durita Mohr; Olsen, Jørn; Bonefeld-Jørgensen, Eva C

    2017-04-01

    In the present case-cohort study based on prospective data from Danish women, we aimed to estimate the main effect of polymorphisms in genes known to be involved in the steroid hormone metabolic pathway and xenobiotic metabolism on the risk of developing breast cancer. We also studied a possible effect measure modification between genotypes and levels of serum perfluoroalkylated substances (PFASs) on the risk to breast cancer. We have previously reported a weak association between serum PFASs levels and the risk of breast cancer for this study population of Danish pregnant nulliparous women as well as in a smaller case-control study of Greenlandic women. The study population consisted of 178 breast cancer cases and 233 controls (tabnulliparous and frequency matched on age) nested within the Danish National Birth Cohort (DNBC), which was established in 1996-2002. Blood samples were drawn at the time of enrollment (6-14 week of gestation). Serum levels of 10 perfluorocarboxylated acids (PFCAs), 5 perfluorosulfonated acids (PFSAs) and 1 sulfonamide (perflurooctane-sulfonamide, PFOSA) were measured. Genotyping was conducted for CYP1A1 (Ile462Val; rs1048943), CYP1B1 (Leu432Val; rs1056836), COMT (Val158Met; rs4680), CYP17A1 (A1→ A2; rs743572); CYP19A1 (C→T; rs10046) by the TaqMan allelic discrimination method. In overall, no significant associations were found between the investigated polymorphisms and the risk of breast cancer in this study among Danish women. The previously found association between PFOSA and risk of breast cancer did vary between different genotypes, with significantly increased risk confined to homozygous carriers of the following alleles: COMT (Met), CYP17 (A1) and CYP19 (C).

  1. Low-Grade Inflammation, Oxidative Stress and Risk of Invasive Post-Menopausal Breast Cancer - A Nested Case-Control Study from the Malmo Diet and Cancer Cohort.

    Directory of Open Access Journals (Sweden)

    Joana A Dias

    Full Text Available Although cancer promotes inflammation, the role of inflammation in tumor-genesis is less well established. The aim was to examine if low-grade inflammation is related to post-menopausal breast cancer risk, and if obesity modifies this association.In the Malmö Diet and Cancer cohort, a nested case-control study was defined among 8,513 women free of cancer and aged 55-73 years at baseline (1991-96; 459 were diagnosed with invasive breast cancer during follow-up (until December 31st, 2010. In laboratory analyses of blood from 446 cases, and 885 controls (matched on age and date of blood sampling we examined systemic inflammation markers: oxidized (ox-LDL, interleukin (IL-1β, IL-6, IL-8, tumor necrosis factor (TNF-α, white blood cells, lymphocytes and neutrophils. Odds ratios (OR and 95% confidence intervals (CI for breast cancer risk was calculated using multivariable conditional logistic regression.Inverse associations with breast cancer were seen in fully-adjusted models, for 2nd and 3rd tertiles of ox-LDL, OR (95% CI: 0.65 (0.47-0.90, 0.63 (0.45-0.89 respectively, p-trend = 0.01; and for the 3rd tertile of TNF-α, 0.65 (0.43-0.99, p-trend = 0.04. In contrast, those in the highest IL-1β category had higher risk, 1.71 (1.05-2.79, p-trend = 0.01. Obesity did not modify associations between inflammation biomarkers and breast cancer.Our study does not suggest that low-grade inflammation increase the risk of post-menopausal breast cancer.

  2. Risk of hip, subtrochanteric, and femoral shaft fractures among mid and long term users of alendronate: nationwide cohort and nested case-control study

    Science.gov (United States)

    Abrahamsen, Bo; Eiken, Pia; Eastell, Richard

    2016-01-01

    Objectives To determine the skeletal safety and efficacy of long term (≥10 years) alendronate use in patients with osteoporosis. Design Open register based cohort study containing two nested case control studies. Setting Nationwide study of population of Denmark. Participants 61 990 men and women aged 50-94 at the start of treatment, who had not previously taken alendronate, 1996-2007. Interventions Treatment with alendronate. Main outcome measures Incident fracture of the subtrochanteric femur or femoral shaft (ST/FS) or the hip. Non-fracture controls from the cohort were matched to fracture cases by sex, year of birth, and year of initiation of alendronate treatment. Conditional logistic regression models were fitted to calculate odds ratios with and without adjustment for comorbidity and comedications. Sensitivity analyses investigated subsequent treatment with other drugs for osteoporosis. Results 1428 participants sustained a ST/FS (incidence rate 3.4/1000 person years, 95% confidence interval 3.2 to 3.6), and 6784 sustained a hip fracture (16.2/1000 person years, 15.8 to 16.6). The risk of ST/FS was lower with high adherence to treatment with alendronate (medication possession ratio (MPR, a proxy for compliance) >80%) compared with poor adherence (MPR 80% was associated with a decreased risk of hip fracture (0.73, 0.68 to 0.78; Pfracture outcomes, even for over 10 years of continuous use. PMID:27353596

  3. The incidence, risk factors, and outcome of transfusion-related acute lung injury in a cohort of cardiac surgery patients: a prospective nested case-control study.

    Science.gov (United States)

    Vlaar, Alexander P J; Hofstra, Jorrit J; Determann, Rogier M; Veelo, Denise P; Paulus, Frederique; Kulik, Wim; Korevaar, Johanna; de Mol, Bas A; Koopman, Marianne M W; Porcelijn, Leendert; Binnekade, Jan M; Vroom, Margreeth B; Schultz, Marcus J; Juffermans, Nicole P

    2011-04-21

    Transfusion-related acute lung injury (TRALI) is the leading cause of transfusion-related morbidity and mortality. Both antibodies and bioactive lipids that have accumulated during storage of blood have been implicated in TRALI pathogenesis. In a single-center, nested, case-control study, patients were prospectively observed for onset of TRALI according to the consensus definition. Of 668 patients, 16 patients (2.4%) developed TRALI. Patient-related risk factors for onset of TRALI were age and time on the cardiopulmonary bypass. Transfusion-related risk factors were total amount of blood products (odds ratio [OR] = 1.2; 95% confidence interval [CI], 1.03-1.44), number of red blood cells stored more than 14 days (OR = 1.6; 95% CI, 1.04-2.37), total amount of plasma (OR = 1.2; 95% CI, 1.03-1.44), presence of antibodies in donor plasma (OR = 8.8; 95% CI, 1.8-44), and total amount of transfused bioactive lipids (OR = 1.0; 95% CI, 1.00-1.07). When adjusted for patient risk factors, only the presence of antibodies in the associated blood products remained a risk factor for TRALI (OR = 14.2; 95% CI, 1.5-132). In-hospital mortality of TRALI was 13% compared with 0% and 3% in transfused and nontransfused patients, respectively (P < .05). In conclusion, the incidence of TRALI is high in cardiac surgery patients and associated with adverse outcome. Our results suggest that cardiac surgery patients may benefit from exclusion of blood products containing HLA/HNA antibodies.

  4. Infection, antibiotic therapy and risk of colorectal cancer: a nationwide nested case-control study in patients with Type 2 diabetes mellitus.

    Science.gov (United States)

    Wang, Jiun-Ling; Chang, Chia-Hsuin; Lin, Jou-Wei; Wu, Li-Chiu; Chuang, Lee-Ming; Lai, Mei-Shu

    2014-08-15

    Patients with Type 2 diabetes mellitus are at a higher risk of colorectal cancer (CRC). The objective of our study was to examine the inter-relationship among infection sites, systemic antibiotic use and risk of CRC among patients with Type 2 diabetes mellitus. From a diabetic cohort from the Taiwan's National Health Insurance claims database, we identified 3,593 incident colon cancer cases, 1,979 rectal cancer cases and 22,288 controls and conducted a nested case-control study to examine the association between antibiotic use and CRC incidence. Logistic regression models were applied to estimate the odds ratio (OR) and the 95% confidence interval (95% CI) between infection sites, antibiotic use and CRC incidence. Patients with intra-abdominal infection were significantly associated with increased risk for colon cancer (OR = 2.01, 95% CI = 1.73-2.35) and rectal cancer (OR = 1.59, 95% CI = 1.26-2.00). Any antianaerobic antibiotic use was associated with a higher risk of colon cancer (OR = 2.31, 95% CI = 2.12-2.52) and rectal cancer (OR = 1.69, 95% CI = 1.50-1.90) but without an obvious dose-response relationship for cumulative use. Antianaerobic antibiotics also increased the risks for those with nonintra-abdominal infection. No association was found between antiaerobic agent use and the CRC risk. The results suggest intra-abdominal infections and antianaerobic antibiotic use may be a marker for precancerous lesions or early CRC, although the possibility of antianaerobic antibiotics playing an additional role cannot be excluded. Further research examining the relationship between intra-abdominal infection, antianaerobic antibiotics use and possible change of microbiota leading to colorectal carcinogenesis is warranted.

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

    Science.gov (United States)

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

    2017-04-15

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

  6. Acrylamide and glycidamide hemoglobin adduct levels and endometrial cancer risk: A nested case-control study in nonsmoking postmenopausal women from the EPIC cohort.

    Science.gov (United States)

    Obón-Santacana, Mireia; Freisling, Heinz; Peeters, Petra H; Lujan-Barroso, Leila; Ferrari, Pietro; Boutron-Ruault, Marie-Christine; Mesrine, Sylvie; Baglietto, Laura; Turzanski-Fortner, Renee; Katzke, Verena A; Boeing, Heiner; Quirós, J Ramón; Molina-Portillo, Elena; Larrañaga, Nerea; Chirlaque, María-Dolores; Barricarte, Aurelio; Khaw, Kay-Tee; Wareham, Nick; Travis, Ruth C; Merritt, Melissa A; Gunter, Marc J; Trichopoulou, Antonia; Lagiou, Pagona; Naska, Androniki; Palli, Domenico; Sieri, Sabina; Tumino, Rosario; Fiano, Valentina; Galassom, Rocco; Bueno-de-Mesquita, H B As; Onland-Moret, N Charlotte; Idahl, Annika; Lundin, Eva; Weiderpass, Elisabete; Vesper, Hubert; Riboli, Elio; Duell, Eric J

    2016-03-01

    Acrylamide, classified in 1994 by IARC as "probably carcinogenic to humans," was discovered in 2002 in some heat-treated, carbohydrate-rich foods. Four prospective studies have evaluated the association between dietary acrylamide intake and endometrial cancer (EC) risk with inconsistent results. The purpose of this nested case-control study, based on the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort, was to evaluate, for the first time, the association between hemoglobin adducts of acrylamide (HbAA) and glycidamide (HbGA) and the risk of developing EC in non-smoking postmenopausal women. Hemoglobin adducts were measured in red blood cells by HPLC/MS/MS. Four exposure variables were evaluated: HbAA, HbGA, their sum (HbAA+HbGA), and their ratio (HbGA/HbAA). The association between hemoglobin adducts and EC was evaluated using unconditional multivariable logistic regression models, and included 383 EC cases (171 were type-I EC), and 385 controls. Exposure variables were analyzed in quintiles based on control distributions. None of the biomarker variables had an effect on overall EC (HRHbAA;Q5vsQ1 : 0.84, 95%CI: 0.49-1.48; HRHbGA;Q5vsQ1 : 0.94, 95%CI: 0.54-1.63) or type-I EC risk. Additionally, none of the subgroups investigated (BMI acrylamide or glycidamide were not associated with EC or type-I EC risk in 768 nonsmoking postmenopausal women from the EPIC cohort.

  7. Implementation of mental health service has an impact on retention in HIV care: a nested case-control study in a japanese HIV care facility.

    Directory of Open Access Journals (Sweden)

    Shinjiro Tominari

    Full Text Available BACKGROUND: Poor retention in the care of patients with human immunodeficiency virus (HIV is associated with adverse patient outcomes such as antiretroviral therapy failure and death. Therefore, appropriate case management is required for better patient retention; however, which intervention in case management is important has not been fully investigated. Meanwhile, in Japan, each local government is required to organize mental health services for patients with HIV so that a case manager at an HIV care facility can utilize them, but little is known about the association between implementation of the services and loss to follow-up. Therefore, we investigated that by a nested case-control study. METHODS: The target population consisted of all patients with HIV who visited Osaka National Hospital, the largest HIV care facility in western Japan, between 2000 and 2010. Loss to follow-up was defined as not returning for follow-up care more than 1 year after the last visit. Independent variables included patient demographics, characteristics of the disease and treatment, and whether the patients have received mental health services. For each case, three controls were randomly selected and matched. RESULTS: Of the 1620 eligible patients, 88 loss to follow-up cases were identified and 264 controls were matched. Multivariate-adjusted conditional logistic regression revealed that loss to follow-up was less frequent among patients who had received mental health services implemented by their case managers (adjusted odds ratio [95% confidence interval] 0.35 [0.16-0.76]. Loss to follow-up also occurred more frequently in patients who did not receive antiretroviral therapy (adjusted odds ratio [95% confidence interval], 7.51 [3.34-16.9], who were under 30 years old (2.74 [1.36-5.50], or who were without jobs (3.38 [1.58-7.23]. CONCLUSION: Mental health service implementation by case managers has a significant impact on patient retention.

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

    Directory of Open Access Journals (Sweden)

    Jieyu Chen

    2017-02-01

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

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

    Science.gov (United States)

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

    2014-05-05

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

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

    Science.gov (United States)

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

    2014-12-14

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

  11. Interactions between genetic admixture, ethnic identity, APOE genotype and dementia prevalence in an admixed Cuban sample; a cross-sectional population survey and nested case-control study

    Directory of Open Access Journals (Sweden)

    Hernandez Milagros

    2011-03-01

    Full Text Available Abstract Background The prevalence and incidence of dementia are low in Nigeria, but high among African-Americans. In these populations there is a high frequency of the risk-conferring APOE-e4 allele, but the risk ratio is less than in Europeans. In an admixed population of older Cubans we explored the effects of ethnic identity and genetic admixture on APOE genotype, its association with dementia, and dementia prevalence. Methods A cross-sectional catchment area survey of 2928 residents aged 65 and over, with a nested case-control study of individual admixture. Dementia diagnosis was established using 10/66 Dementia and DSM-IV criteria. APOE genotype was determined in 2520 participants, and genetic admixture in 235 dementia cases and 349 controls. Results Mean African admixture proportions were 5.8% for 'white', 28.6% for 'mixed' and 49.6% for 'black' ethnic identities. All three groups were substantially admixed with considerable overlap. African admixture was linearly related to number of APOE-e4 alleles. One or more APOE-e4 alleles was associated with dementia in 'white' and 'black' but not 'mixed' groups but neither this, nor the interaction between APOE-e4 and African admixture (PR 0.52, 95% CI 0.13-2.08 were statistically significant. Neither ethnic identity nor African admixture was associated with dementia prevalence when assessed separately. However, considering their joint effects African versus European admixture was independently associated with a higher prevalence, and 'mixed' or 'black' identity with a lower prevalence of dementia. Conclusions APOE genotype is strongly associated with ancestry. Larger studies are needed to confirm whether the concentration of the high-risk allele in those with African ancestry is offset by an attenuation of its effect. Counter to our hypothesis, African admixture may be associated with higher risk of dementia. Although strongly correlated, effects of admixture and ethnic identity should be

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

    Science.gov (United States)

    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.

  13. Potential self-selection bias in a nested case-control study on indoor environmental factors and their association with asthma and allergic symptoms among pre-school children

    DEFF Research Database (Denmark)

    Bornehag, Carl-Gustaf; Sundell, Jan; Sigsgaard, T.;

    2006-01-01

    , including health, building characteristics of the home, and socioeconomic factors between participating and non-participating families in a nested case-control study on asthma and allergy among children. Information was collected in a baseline questionnaire to the parents of 14,077 children aged 1-6 years...... in a first step. In a second step 2,156 of the children were invited to participate in a case-control study. Of these, 198 cases and 202 controls were finally selected. For identifying potential selection bias, information concerning all invited families in the case-control study was obtained from...... the baseline questionnaire. Results show that there are several possible biases due to self-selection involved in an extensive study on the impact of the home environment on asthma and allergy among children. Factors associated with participating were high socioeconomic status of the family, more health...

  14. A Note on Penalized Regression Spline Estimation in the Secondary Analysis of Case-Control Data

    KAUST Repository

    Gazioglu, Suzan

    2013-05-25

    Primary analysis of case-control studies focuses on the relationship between disease (D) and a set of covariates of interest (Y, X). A secondary application of the case-control study, often invoked in modern genetic epidemiologic association studies, is to investigate the interrelationship between the covariates themselves. The task is complicated due to the case-control sampling, and to avoid the biased sampling that arises from the design, it is typical to use the control data only. In this paper, we develop penalized regression spline methodology that uses all the data, and improves precision of estimation compared to using only the controls. A simulation study and an empirical example are used to illustrate the methodology.

  15. Lung cancer risk among bricklayers in a pooled analysis of case-control studies.

    NARCIS (Netherlands)

    Consonni, Dario; De Matteis, Sara; Olsson, Ann; Pesch, Beate; Kromhout, Hans; Straif, Kurt; Brüning, Thomas

    2014-01-01

    OBJECTIVES: Bricklayers may be exposed to several lung carcinogens, including crystalline silica and asbestos. Previous studies reported an excess of lung cancer among these workers. We examined lung cancer risk among bricklayers within SYNERGY, a large international pooled analysis of case-control

  16. Oral Bisphosphonates and Upper Gastrointestinal Cancer Risks in Asians with Osteoporosis: A Nested Case-Control Study Using National Retrospective Cohort Sample Data from Korea.

    Directory of Open Access Journals (Sweden)

    Sun-Young Jung

    Full Text Available Bisphosphonate can irritate the gastrointestinal mucosa and increase the risk of esophageal or gastric cancer. The relatively high prevalence of upper gastrointestinal cancers and the widespread use of bisphosphonate in Korea call for further investigation. We conducted a case-control study to evaluate the risk of esophageal or gastric cancer after exposure to oral bisphosphonates in Korean patients with osteoporosis.We used the National Health Insurance Service-National Sample Cohort database of Korea from 2002 to 2013. Among osteoporotic patients (>40 years, cases were defined as incident diagnosis of esophageal or gastric cancer between 2006 and 2013. For each case, four controls were matched for age, sex, and income level by type of insurance. We categorized bisphosphonate use as non-user, recent user, past user, and past and recent user, depending on prescription in two periods (1 to 2 years and 2 to 4 years prior to the index date. We also assessed the duration of bisphosphonate use by measuring cumulative duration of exposure (CDE. To examine the association between oral bisphosphonates and esophageal or gastric cancer, we estimated adjusted odds ratios (aORs and 95% confidence intervals (CIs using conditional logistic regression analysis, adjusting for concomitant diseases.A total of 1,708 cases and 6,832 controls were identified. The aORs (95% CIs of recent, past, and continuous bisphosphonate use compared to non-users were 1.18 (0.93-1.51, 1.04 (0.83-1.29, and 1.25 (0.95-1.58, respectively. In addition, no significant association was observed by CDE, even when different outcome definitions were applied.This study did not prove an increased risk of esophageal or gastric cancer risk associated with bisphosphonate use, with respect to both risk windows and duration of exposure, in an Asian population-based, real-world setting.

  17. Robust estimation for homoscedastic regression in the secondary analysis of case-control data

    KAUST Repository

    Wei, Jiawei

    2012-12-04

    Primary analysis of case-control studies focuses on the relationship between disease D and a set of covariates of interest (Y, X). A secondary application of the case-control study, which is often invoked in modern genetic epidemiologic association studies, is to investigate the interrelationship between the covariates themselves. The task is complicated owing to the case-control sampling, where the regression of Y on X is different from what it is in the population. Previous work has assumed a parametric distribution for Y given X and derived semiparametric efficient estimation and inference without any distributional assumptions about X. We take up the issue of estimation of a regression function when Y given X follows a homoscedastic regression model, but otherwise the distribution of Y is unspecified. The semiparametric efficient approaches can be used to construct semiparametric efficient estimates, but they suffer from a lack of robustness to the assumed model for Y given X. We take an entirely different approach. We show how to estimate the regression parameters consistently even if the assumed model for Y given X is incorrect, and thus the estimates are model robust. For this we make the assumption that the disease rate is known or well estimated. The assumption can be dropped when the disease is rare, which is typically so for most case-control studies, and the estimation algorithm simplifies. Simulations and empirical examples are used to illustrate the approach.

  18. Concurrent use of diuretics, angiotensin converting enzyme inhibitors, and angiotensin receptor blockers with non-steroidal anti-inflammatory drugs and risk of acute kidney injury: nested case-control study

    Science.gov (United States)

    Lapi, Francesco; Azoulay, Laurent; Yin, Hui; Nessim, Sharon J

    2013-01-01

    Objectives To assess whether a double therapy combination consisting of diuretics, angiotensin converting enzyme inhibitors, or angiotensin receptor blockers with addition of non-steroidal anti-inflammatory drugs (NSAIDs) and the triple therapy combination of two of the aforementioned antihypertensive drugs to which NSAIDs are added are associated with an increased risk of acute kidney injury. Design Retrospective cohort study using nested case-control analysis. Setting General practices contributing data to the UK Clinical Practice Research Datalink linked to the Hospital Episodes Statistics database. Participants A cohort of 487 372 users of antihypertensive drugs. Main outcome measures Rate ratios with 95% confidence intervals of acute kidney injury associated with current use of double and triple therapy combinations of antihypertensive drugs with NSAIDs. Results During a mean follow-up of 5.9 (SD 3.4) years, 2215 cases of acute kidney injury were identified (incidence rate 7/10 000 person years). Overall, current use of a double therapy combination containing either diuretics or angiotensin converting enzyme inhibitors or angiotensin receptor blockers with NSAIDs was not associated with an increased rate of acute kidney injury. In contrast, current use of a triple therapy combination was associated with an increased rate of acute kidney injury (rate ratio 1.31, 95% confidence interval 1.12 to 1.53). In secondary analyses, the highest risk was observed in the first 30 days of use (rate ratio 1.82, 1.35 to 2.46). Conclusions A triple therapy combination consisting of diuretics with angiotensin converting enzyme inhibitors or angiotensin receptor blockers and NSAIDs was associated with an increased risk of acute kidney injury. The risk was greatest at the start of treatment. Although antihypertensive drugs have cardiovascular benefits, vigilance may be warranted when they are used concurrently with NSAIDs. PMID:23299844

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

    Science.gov (United States)

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

    2015-03-15

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

  20. A FORTRAN program for stratified analysis of data from case-control studies.

    Science.gov (United States)

    Koepsell, T D

    1983-04-01

    Stratification of study subjects by one or more covariates is a commonly accepted method for dealing with confounding and effect modification in epidemiologic case-control studies. A flexible FORTRAN program is described which facilitates simultaneous stratification by several covariates and which produces summary odds ratio estimates and chi-square statistics by the Mantel-Haenszel method. It also facilitates detection of effect modification by each covariate considered individually. Straightforward means are provided for the user to modify input data before analysis or to exclude certain subjects from analysis, simulating such capabilities in larger statistical packages.

  1. Performance of the colorectal cancer screening marker Sept9 is influenced by age, diabetes and arthritis: a nested case-control study

    DEFF Research Database (Denmark)

    Ørntoft, Mai-Britt Worm; Nielsen, Hans Jørgen; Ørntoft, Torben Falck;

    2015-01-01

    Using a retrospective nested case–control study design, we studied plasma from 150 cancer and 150 controls selected from a well-characterized cohort of 4698 subjects referred for diagnostic colonoscopy due to CRC-related symptoms. The cases and controls were matched on age and gender, and moreover cases......Background Annually, colorectal cancer (CRC) is diagnosed in >1.4 million subjects worldwide and incidence is increasing. Much effort has therefore been focused on screening, which has proven to reduce cancer-related mortality. The Sept9 DNA-methylation assay is among the most well studied blood...... sensitivity 73 % (95 % CI, 64–80 %) and specificity 82 % (95 % CI, 75–88 %), respectively. Age >65 was associated with both increased false positive and false negative results (p Arthritis was associated with a higher false negative rate (p = 0.005) whereas Arteriosclerosis was associated...

  2. Nested Case-control Study on Risk Factors of Upper Gastrointestinal Bleeding%上消化道出血危险因素的巢式病例对照研究

    Institute of Scientific and Technical Information of China (English)

    孙毅鸿; 邵伟; 王怡; 周达成; 严飞飞; 冯靓; 郑荣远

    2012-01-01

    Objective;To evaluate aspirin-related medication risk and independent risk factors of upper gastrointestinal bleeding. Methods;Adopting the nested case control study to investigate 293 patients with more than 50-years-old who undergone gastroscopy at a hospital. 145 patients diagnosed with upper gastrointestinal bleeding selected as the case group and another 148 patients diagnosed with non upper gastrointestinal bleeding selected as the control group. To screen the medication risk factors of upper gastrointestinal bleeding, the data of patients from the retrospective study was gone on statistical analysis. A retrospective cohort study was nested in the case control study, which 73 patients took aspirin selected as the exposure group and 220 patients did not take aspirin selected as the non-exposure group. The incidence rate of upper gastrointestinal bleeding with two groups were compared and analyzed. Results;The case control study showed that old age (elderly) , smoking, aspirin taking, and NSAIDs taking were independent risk factors for upper gastrointestinal bleeding ( aspirin: OR = 1. 802, 95 % CI: 1. 005 ~ 3. 230). The cohort study analysis showed that the incidence of upper gastrointestinal bleeding in the exposure group taking aspirin in patients was 61. 6% , significantly higher than the non-exposed group with incidence of 45. 5% (P <0. 05 , RR = 1. 354, AR = 16. 1% ). Conclusion: Four independent risk factors for upper gastrointestinal bleeding were selected out from hospital population of elderly patients undergone with gastroscopy. Taking aspirin is an independent risk factor, closely associated with the incidence of upper gastrointestinal bleeding. We recommend that aspirin should avoid to be used in the patients with underlying diseases of the gastrointestinal mucosa or stroke with only a low recurrence risk.%目的:评价卒中预防药物阿司匹林引发上消化道出血的用药风险.方法:采用回顾性巢式

  3. Sex Steroid Hormone Gene Variants, Pesticide Use and the Risk of Prostate Cancer: A Nested Case-Control Study within the Agricultural Health Study

    Directory of Open Access Journals (Sweden)

    Carol H Christensen

    2016-11-01

    Full Text Available Experimental and epidemiologic investigations suggest that certain pesticides may alter sex steroid hormone synthesis, metabolism or regulation and the risk of hormone-related cancers. Here we evaluated whether single nucleotide polymorphisms (SNPs involved in hormone homeostasis alter the effect of pesticide exposure on prostate cancer risk. We evaluated pesticide–SNP interactions between 39 pesticides and SNPs with respect to prostate cancer among 776 cases and 1444 controls nested in the Agricultural Health Study cohort. In these interactions, we included candidate SNPs involved in hormone synthesis, metabolism and regulation (N=1100, as well as SNPs associated with circulating sex steroid concentrations as identified by genome-wide association studies (N=17. Unconditional logistic regression was used to estimate odds ratios (ORs and 95% confidence intervals (CIs. Multiplicative SNP–pesticide interactions were calculated using a likelihood ratio test. We translated p-values for interaction into q-values, which reflected the false discovery rate, to account for multiple comparisons. We observed a significant interaction, which was robust to multiple comparison testing, between the herbicide dicamba and rs8192166 in the testosterone metabolizing gene SRD5A1 (p-interaction=4.0x10-5; q-value=0.03, such that men with two copies of the wild-type genotype CC had a reduced risk of prostate cancer associated with low use of dicamba (OR=0.62 95% CI: 0.41, 0.93, and high use of dicamba (OR=0.44, 95% CI: 0.29, 0.68, compared to those who reported no use of dicamba; in contrast, there was no significant association between dicamba and prostate cancer among those carrying one or two copies of the variant T allele at rs8192166. In addition, interactions between two organophosphate insecticides and SNPs related to estradiol metabolism were observed to result in an increased risk of prostate cancer. While replication is needed, these data suggest both

  4. Case-control studies of gene-environment interaction: Bayesian design and analysis.

    Science.gov (United States)

    Mukherjee, Bhramar; Ahn, Jaeil; Gruber, Stephen B; Ghosh, Malay; Chatterjee, Nilanjan

    2010-09-01

    With increasing frequency, epidemiologic studies are addressing hypotheses regarding gene-environment interaction. In many well-studied candidate genes and for standard dietary and behavioral epidemiologic exposures, there is often substantial prior information available that may be used to analyze current data as well as for designing a new study. In this article, first, we propose a proper full Bayesian approach for analyzing studies of gene-environment interaction. The Bayesian approach provides a natural way to incorporate uncertainties around the assumption of gene-environment independence, often used in such an analysis. We then consider Bayesian sample size determination criteria for both estimation and hypothesis testing regarding the multiplicative gene-environment interaction parameter. We illustrate our proposed methods using data from a large ongoing case-control study of colorectal cancer investigating the interaction of N-acetyl transferase type 2 (NAT2) with smoking and red meat consumption. We use the existing data to elicit a design prior and show how to use this information in allocating cases and controls in planning a future study that investigates the same interaction parameters. The Bayesian design and analysis strategies are compared with their corresponding frequentist counterparts.

  5. Analysis of Case-Control Association Studies: SNPs, Imputation and Haplotypes

    KAUST Repository

    Chatterjee, Nilanjan

    2009-11-01

    Although prospective logistic regression is the standard method of analysis for case-control data, it has been recently noted that in genetic epidemiologic studies one can use the "retrospective" likelihood to gain major power by incorporating various population genetics model assumptions such as Hardy-Weinberg-Equilibrium (HWE), gene-gene and gene-environment independence. In this article we review these modern methods and contrast them with the more classical approaches through two types of applications (i) association tests for typed and untyped single nucleotide polymorphisms (SNPs) and (ii) estimation of haplotype effects and haplotype-environment interactions in the presence of haplotype-phase ambiguity. We provide novel insights to existing methods by construction of various score-tests and pseudo-likelihoods. In addition, we describe a novel two-stage method for analysis of untyped SNPs that can use any flexible external algorithm for genotype imputation followed by a powerful association test based on the retrospective likelihood. We illustrate applications of the methods using simulated and real data. © Institute of Mathematical Statistics, 2009.

  6. Association of proteinuria threshold in pre-eclampsia with maternal and perinatal outcomes: a nested case control cohort of high risk women.

    Directory of Open Access Journals (Sweden)

    Kate Bramham

    Full Text Available OBJECTIVES: To evaluate occurrence of adverse maternal and perinatal outcomes with different thresholds of proteinuria (300-499 mg and ≥500 mg/24 hours in pre-eclamptic women, comparing outcomes against women with chronic and gestational hypertension. DESIGN: Secondary analysis of the Vitamins in Pre-Eclampsia Trial. SETTING: 25 UK hospitals in ten geographical areas. POPULATION: 946 women with pre-existing risk factors for pre-eclampsia. METHODS: Women with pre-eclampsia and proteinuria 300-499 mg/24 h (PE300, referent group, n=60 or proteinuria ≥500 mg/24 h (PE500, n=161 were compared with two groups of non-proteinuric women with chronic hypertension (CHT, n=615 or gestational hypertension (GH, n=110. MAIN OUTCOME MEASURES: MATERNAL: progression to severe hypertension. Perinatal: small for gestational age (SGA <5(th centile, gestation at delivery. RESULTS: Severe hypertension occurred more frequently in PE500 (35% and PE300 (27% than CHT (5.9%; P≤0.01 and GH (10%; p≤0.001. Gestation at delivery was earlier in PE500 (33.2 w than PE300 (37.3 w; P≤0.001, and later in CHT (38.3 w; P≤0.05 and GH (39.1 w; P≤0.001. SGA infants were more frequent in PE300 (32% than in CHT (13.3%; P≤0.001 and GH (16.5%; P≤0.05. Women in PE500 were more likely to have a caesarean section than PE300 (78% vs. 48%; P≤0.001, and to receive magnesium sulphate (17% vs. 1.7%, P≤0.05. CONCLUSION: Women with PE300 have complication rates above those of women managed as out-patients (GH and CHT, meriting closer surveillance and confirming 300 mg/d as an appropriate threshold for determining in-patient management. Adverse perinatal outcomes are higher still in women with PE500.

  7. Management of Esophageal Carcinoma Associated with Cirrhosis: A Retrospective Case-Control Analysis

    Directory of Open Access Journals (Sweden)

    Florence Trivin

    2009-01-01

    Full Text Available Objectives. Esophageal carcinoma and cirrhosis have the overlapping etiologic factors. Methods. In a retrospective analysis conducted in 2 Breton institutions we wanted to asses the frequency of this association and the outcome of these patients in a case-control study where each case (cirrhosis and esophageal cancer was paired with two controls (esophageal cancer. Results. In a 10-year period, we have treated 958 esophageal cancer patients; 26 (2.7% had a cirrhosis. The same treatments were proposed to the 2 groups; cases received nonsignificantly different radiation and chemotherapy dose than controls. Severe toxicities and deaths were more frequent among the cases. At the end of the treatment 58% of the cases and 67% of the controls were in complete remission; median and 2-year survival were not different between the 2 groups. All 4 Child-Pugh B class patients experienced severe side effects and 2 died during the treatment. Conclusions. This association is surprisingly infrequent in our population! Child-Pugh B patients had a dismal prognosis and a bad tolerance to radiochemotherapy; Child-Pugh A patients have the same tolerance and the same prognosis as controls and the evidence of a well-compensated cirrhosis has not modified our medical options.

  8. Maternal age and Alzheimer's disease: a collaborative re-analysis of case-control studies. EURODEM Risk Factors Research Group

    NARCIS (Netherlands)

    W.A. Rocca; C.M. van Duijn (Cock); D.G. Clayton (David); V. Chandra; L. Fratiglioni (Laura); A.B. Graves; A. Heyman; A.F. Jorm; E. Kokmen (Emre); K. Kondo; J.A. Mortimer; S.L. Shalat; H. Soininen; A. Hofman (Albert)

    1991-01-01

    textabstractTo investigate the possible association between Alzheimer's disease and late maternal age at index birth, we conducted a collaborative re-analysis of existing case-control data sets. Of the 11 studies participating in the EURODEM project, four were included in the analyses regarding mate

  9. Interaction between genetic and environmental risk factors for Alzheimer's disease: a re-analysis of case-control studies

    NARCIS (Netherlands)

    C.M. van Duijn (Cock); D.G. Clayton (David); V. Chandra; L. Fratiglioni (Laura); A.B. Graves; A. Heyman; A.F. Jorm; E. Kokmen (Emre); K. Kondo; J.A. Mortimer; W.A. Rocca; S.L. Shalat; H. Soininen; A. Hofman (Albert)

    1994-01-01

    textabstractTo study the interaction among genetic and environmental risk factors, a reanalysis of case-control studies of Alzheimer's disease (AD) was conducted based on the original data of all studies carried out to January 1, 1990. Seven studies were included in the present analysis, comprising

  10. Head trauma as a risk factor for Alzheimer's disease: A collaborative re-analysis of case-control studies

    NARCIS (Netherlands)

    J.A. Mortimer; C.M. van Duijn (Cock); V. Chandra; L. Fratiglioni (Laura); A.B. Graves; A. Heyman; A.F. Jorm; E. Kokmen (Emre); K. Kondo; W.A. Rocca; S.L. Shalat; H. Soininen; A. Hofman (Albert)

    1991-01-01

    textabstractA re-analysis of the data from 11 case-control studies was performed to investigate the association between head trauma and Alzheimer's disease (AD). To increase comparability of studies, exposures were limited to head trauma with loss of consciousness (hereafter referred to as 'head tra

  11. ABO blood group system and gastric cancer: a case-control study and meta-analysis.

    Science.gov (United States)

    Wang, Zhiwei; Liu, Lei; Ji, Jun; Zhang, Jianian; Yan, Min; Zhang, Jun; Liu, Bingya; Zhu, Zhenggang; Yu, Yingyan

    2012-10-17

    This study focuses on the association between the ABO blood group system and the risk of gastric cancer or Helicobacter pylori infection. The data for the ABO blood group was collected from 1045 cases of gastric cancer, whereby the patient underwent a gastrectomy in Ruijin Hospital, Shanghai. The information on the ABO blood group from 53,026 healthy blood donors was enrolled as control. We searched the Pubmed database on the relationship between ABO blood groups and gastric cancer risk for meta-analysis. In our case-control study, the risk of gastric cancer in blood group A was significantly higher than that in non-A groups (O, B and AB) (odd ratio, OR1.34; 95% confidential interval, CI 1.25-1.44). Compared with non-O groups (A, B and AB), individuals with blood group O demonstrated a reduced risk of gastric cancer (OR = 0.80; 95% CI 0.72-0.88). The proportion of H. pylori infection in blood group A individuals was significantly higher than that in non-A blood groups (OR = 1.42; 95% CI 1.05-1.93). We further combined our data with the published data of others, and crossreferenced the risk of gastric cancer with the blood type, finding consistent evidence that gastric cancer risk in the blood A group was higher than that in the non-A groups (OR = 1.11; 95% CI 1.07-1.15), and that blood type O individuals were consistently shown gastric cancer risk reduction (OR = 0.91; 95% CI 0.89-0.94). Our study concluded that there was a slightly increased risk of gastric cancer in blood group A individuals, and people with blood type A are more prone to be infected by H. pylori than other ABO blood type individuals, whereas, a slightly decreased risk of gastric cancer was identified in blood type O individuals.

  12. Decision curve analysis revisited: overall net benefit, relationships to ROC curve analysis, and application to case-control studies

    Directory of Open Access Journals (Sweden)

    Zumbrunn Thomas

    2011-06-01

    Full Text Available Abstract 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.

  13. Recreational physical activity and epithelial ovarian cancer: a case-control study, systematic review, and meta-analysis.

    Science.gov (United States)

    Olsen, Catherine M; Bain, Christopher J; Jordan, Susan J; Nagle, Christina M; Green, Adèle C; Whiteman, David C; Webb, Penelope M

    2007-11-01

    It remains unclear whether physical activity is associated with epithelial ovarian cancer risk. We therefore examined the association between recreational physical activity and risk of ovarian cancer in a national population-based case-control study in Australia. We also systematically reviewed all the available evidence linking physical activity with ovarian cancer to provide the best summary estimate of the association. The case-control study included women ages 18 to 79 years with a new diagnosis of invasive (n=1,269) or borderline (n=311) epithelial ovarian cancer identified through a network of clinics, physicians, and state cancer registries throughout Australia. Controls (n=1,509) were randomly selected from the national electoral roll and were frequency matched to cases by age and state. For the systematic review, we identified eligible studies using Medline, the ISI Science Citation Index, and manual review of retrieved references, and included all case-control or cohort studies that permitted assessment of an association between physical activity (recreational/occupational/sedentary behavior) and histologically confirmed ovarian cancer. Meta-analysis was restricted to the subset of these studies that reported on recreational physical activity. In our case-control study, we observed weakly inverse or null associations between recreational physical activity and risk of epithelial ovarian cancer overall. There was no evidence that the effects varied by tumor behavior or histologic subtype. Twelve studies were included in the meta-analysis, which gave summary estimates of 0.79 (95% confidence interval, 0.70-0.85) for case-control studies and 0.81 (95% confidence interval, 0.57-1.17) for cohort studies for the risk of ovarian cancer associated with highest versus lowest levels of recreational physical activity. Thus, pooled results from observational studies suggest that a modest inverse association exists between level of recreational physical activity and

  14. A method for detecting epistasis in genome-wide studies using case-control multi-locus association analysis

    OpenAIRE

    Galan Jose; Quintas Antonio; Royo Jose; Sáez María; Bermudo Fernando; González-Pérez Antonio; Gayán Javier; Morón Francisco; Ramirez-Lorca Reposo; Real Luis; Ruiz Agustín

    2008-01-01

    Abstract Background The difficulty in elucidating the genetic basis of complex diseases roots in the many factors that can affect the development of a disease. Some of these genetic effects may interact in complex ways, proving undetectable by current single-locus methodology. Results We have developed an analysis tool called Hypothesis Free Clinical Cloning (HFCC) to search for genome-wide epistasis in a case-control design. HFCC combines a relatively fast computing algorithm for genome-wide...

  15. Multilevel Analysis Methods for Partially Nested Cluster Randomized Trials

    Science.gov (United States)

    Sanders, Elizabeth A.

    2011-01-01

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

  16. High Sodium Intake Is Associated With Self-Reported Rheumatoid Arthritis: A Cross Sectional and Case Control Analysis Within the SUN Cohort.

    Science.gov (United States)

    Salgado, Eva; Bes-Rastrollo, Maira; de Irala, Jokin; Carmona, Loreto; Gómez-Reino, Juan J

    2015-09-01

    Sodium intake is a potential environmental factor for immune-mediated inflammatory diseases. The aim of this study is to investigate the association of sodium intake with rheumatoid arthritis. We performed a cross-sectional study nested in a highly educated cohort investigating dietary habits as determinants of disease. Daily sodium intake in grams per day was estimated from a validated food frequency questionnaire. We identified prevalent self-reported cases of rheumatoid arthritis. Logistic regression models were used to estimate the odds ratio for rheumatoid arthritis by sodium intake adjusting for confounders. Linear trend tests and interactions between variables were explored. Sensitivity analyses included age- and sex-matched case-control study, logistic multivariate model adjusted by residuals, and analysis excluding individuals with prevalent diabetes or cardiovascular disease. The effective sample size was 18,555 individuals (mean age 38-years old, 60% women) including 392 self-reported rheumatoid arthritis. Median daily sodium intake (estimated from foods plus added salt) was 3.47 (P25-75: 2.63-4.55) grams. Total sodium intake in the fourth quartile showed a significant association with rheumatoid arthritis (fully adjusted odds ratio 1.5; 95% CI 1.1-2.1, P for trend = 0.02). Never smokers with high sodium intake had higher association than ever smokers with high sodium intake (P for interaction = 0.007). Dose-dependent association was replicated in the case-control study. High sodium intake may be associated with a diagnosis of rheumatoid arthritis. This confirms previous clinical and experimental research.

  17. Conditional likelihood methods for haplotype-based association analysis using matched case-control data.

    Science.gov (United States)

    Chen, Jinbo; Rodriguez, Carmen

    2007-12-01

    Genetic epidemiologists routinely assess disease susceptibility in relation to haplotypes, that is, combinations of alleles on a single chromosome. We study statistical methods for inferring haplotype-related disease risk using single nucleotide polymorphism (SNP) genotype data from matched case-control studies, where controls are individually matched to cases on some selected factors. Assuming a logistic regression model for haplotype-disease association, we propose two conditional likelihood approaches that address the issue that haplotypes cannot be inferred with certainty from SNP genotype data (phase ambiguity). One approach is based on the likelihood of disease status conditioned on the total number of cases, genotypes, and other covariates within each matching stratum, and the other is based on the joint likelihood of disease status and genotypes conditioned only on the total number of cases and other covariates. The joint-likelihood approach is generally more efficient, particularly for assessing haplotype-environment interactions. Simulation studies demonstrated that the first approach was more robust to model assumptions on the diplotype distribution conditioned on environmental risk variables and matching factors in the control population. We applied the two methods to analyze a matched case-control study of prostate cancer.

  18. 痰热清注射液所致静脉炎危险因素巢式病例对照研究%A nested case control study on risk factors of phlebitis caused by Tanreqing Injection

    Institute of Scientific and Technical Information of China (English)

    张立宏; 芮婷; 李家珍; 韩旭; 李莉; 张素秋

    2013-01-01

    Objective: To investigate the risk factors of Tanreqing Injection related phlebitis. To help for the development of nursing interventions which can prevent the occurrence of phlebitis related to Tanreqing Injection. Methods: A nested case-control study was performed to identify the risk factors. Patients admitted to pulmonary department from Jan.2010 to Dec.2011 and injected with Tanreqing were reviewed. Patients who developed phlebitis were identified as cases and others as control group. Two random controls were selected from control group to match with one individul case according to sex, age. A univariate and multivariate conditional logistic regression was used to calculate the odds ratio (OS) of different risk factors. Results: The phlebitis caused by infusion Tanreqing Injection have greatly correlation in infusion time and the catheter indwelling time. Conclusion: The phlebitis caused by Tanreqing Injection were related to many factors. The nurses should pay attention to it in daily practices.%目的:探讨痰热清注射液易引起静脉炎的危险因素,为制订合理使用痰热清注射液,预防静脉炎的护理措施提供参考.方法:样本来自中国中医科学院广安门医院呼吸科自2010年1月至2011年12月2年内输注痰热清的病人,发生静脉炎者与未发生者根据性别、年龄按1∶2比例进行匹配.采取巢式病例对照研究方法,采用优势比(OR)与条件Logistic回归方法,最终确定痰热清注射液导致静脉炎的相关因素.结果:痰热清注射液导致静脉炎与痰热清注射液输注时间以及留置针留滞时间有很大相关性.结论:痰热清注射液导致静脉炎与很多因素有关,在临床护理工作中,应引起护理人员重视.

  19. Urinary amino acid alterations in 3-year-old children with neurodevelopmental effects due to perinatal dioxin exposure in Vietnam: a nested case-control study for neurobiomarker discovery.

    Directory of Open Access Journals (Sweden)

    Muneko Nishijo

    Full Text Available In our previous study of 3-year-old children in a dioxin contamination hot spot in Vietnam, the high total dioxin toxic equivalent (TEQ-PCDDs/Fs-exposed group during the perinatal period displayed lower Bayley III neurodevelopmental scores, whereas the high 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD-exposed group displayed increased autistic traits. In autistic children, urinary amino acid profiles have revealed metabolic alterations in the amino acids that serve as neurotransmitters in the developing brain. Therefore, our present study aimed to investigate the use of alterations in urinary amino acid excretion as biomarkers of dioxin exposure-induced neurodevelopmental deficits in highly exposed 3-year-old children in Vietnam. A nested case-control study of urinary analyses was performed for 26 children who were selected from 111 3-year-old children whose perinatal dioxin exposure levels and neurodevelopmental status were examined in follow-up surveys conducted in a dioxin contaminated hot spot. We compared urinary amino acid levels between the following 4 groups: (1 a high TEQ-PCDDs/Fs and high TCDD-exposed group; (2 a high TEQ-PCDDs/Fs but low TCDD-exposed group; (3 a low TEQ-PCDDs/Fs exposed and poorly developed group; and (4 a low TEQ-PCDDs/Fs exposed and well-developed group. Urinary levels of histidine and tryptophan were significantly decreased in the high TEQ-PCDDs/Fs and high TCDD group, as well as in the high TEQ-PCDDs/Fs but low TCDD group, compared with the low TEQ-PCDDs/Fs and well-developed group. However, the ratio of histidine to glycine was significantly lower only in the high TEQ-PCDDs/Fs and high TCDD group. Furthermore, urinary histidine levels and the ratio of histidine to glycine were significantly correlated with neurodevelopmental scores, particularly for language and fine motor skills. These results indicate that urinary histidine is specifically associated with dioxin exposure-induced neurodevelopmental deficits

  20. Urinary amino acid alterations in 3-year-old children with neurodevelopmental effects due to perinatal dioxin exposure in Vietnam: a nested case-control study for neurobiomarker discovery.

    Science.gov (United States)

    Nishijo, Muneko; Tai, Pham The; Anh, Nguyen Thi Nguyet; Nghi, Tran Ngoc; Nakagawa, Hideaki; Van Luong, Hoang; Anh, Tran Hai; Morikawa, Yuko; Waseda, Tomoo; Kido, Teruhiko; Nishijo, Hisao

    2015-01-01

    In our previous study of 3-year-old children in a dioxin contamination hot spot in Vietnam, the high total dioxin toxic equivalent (TEQ-PCDDs/Fs)-exposed group during the perinatal period displayed lower Bayley III neurodevelopmental scores, whereas the high 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-exposed group displayed increased autistic traits. In autistic children, urinary amino acid profiles have revealed metabolic alterations in the amino acids that serve as neurotransmitters in the developing brain. Therefore, our present study aimed to investigate the use of alterations in urinary amino acid excretion as biomarkers of dioxin exposure-induced neurodevelopmental deficits in highly exposed 3-year-old children in Vietnam. A nested case-control study of urinary analyses was performed for 26 children who were selected from 111 3-year-old children whose perinatal dioxin exposure levels and neurodevelopmental status were examined in follow-up surveys conducted in a dioxin contaminated hot spot. We compared urinary amino acid levels between the following 4 groups: (1) a high TEQ-PCDDs/Fs and high TCDD-exposed group; (2) a high TEQ-PCDDs/Fs but low TCDD-exposed group; (3) a low TEQ-PCDDs/Fs exposed and poorly developed group; and (4) a low TEQ-PCDDs/Fs exposed and well-developed group. Urinary levels of histidine and tryptophan were significantly decreased in the high TEQ-PCDDs/Fs and high TCDD group, as well as in the high TEQ-PCDDs/Fs but low TCDD group, compared with the low TEQ-PCDDs/Fs and well-developed group. However, the ratio of histidine to glycine was significantly lower only in the high TEQ-PCDDs/Fs and high TCDD group. Furthermore, urinary histidine levels and the ratio of histidine to glycine were significantly correlated with neurodevelopmental scores, particularly for language and fine motor skills. These results indicate that urinary histidine is specifically associated with dioxin exposure-induced neurodevelopmental deficits, suggesting that

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

    Directory of Open Access Journals (Sweden)

    Benninga Marc A

    2005-07-01

    Full Text Available Abstract Background In children with severe generalized cerebral palsy, pneumonias are a major health issue. Malnutrition, dysphagia, gastro-oesophageal reflux, impaired respiratory function and constipation are hypothesized risk factors. Still, no data are available on the relative contribution of these possible risk factors in the described population. This paper describes the initiation of a study in 194 children with severe generalized cerebral palsy, on the prevalence and on the impact of these hypothesized risk factors of recurrent pneumonias. Methods/Design A nested case-control design with 18 months follow-up was chosen. Dysphagia, respiratory function and constipation will be assessed at baseline, malnutrition and gastro-oesophageal reflux at the end of the follow-up. The study population consists of a representative population sample of children with severe generalized cerebral palsy. Inclusion was done through care-centres in a predefined geographical area and not through hospitals. All measurements will be done on-site which sets high demands on all measurements. If these demands were not met in "gold standard" methods, other methods were chosen. Although the inclusion period was prolonged, the desired sample size of 300 children was not met. With a consent rate of 33%, nearly 10% of all eligible children in the Netherlands are included (n = 194. The study population is subtly different from the non-participants with regard to severity of dysphagia and prevalence rates of pneumonias and gastro-oesophageal reflux. Discussion Ethical issues complicated the study design. Assessment of malnutrition and gastro-oesophageal reflux at baseline was considered unethical, since these conditions can be easily treated. Therefore, we postponed these diagnostics until the end of the follow-up. In order to include a representative sample, all eligible children in a predefined geographical area had to be contacted. To increase the consent rate, on

  2. Catastrophic health expenditure: a comparative analysis of empty-nest and non-empty-nest households with seniors in Shandong, China

    Science.gov (United States)

    Yang, Tingting; Chu, Jie; Zhou, Chengchao; Medina, Alexis; Li, Cuicui; Jiang, Shan; Zheng, Wengui; Sun, Liyuan; Liu, Jing

    2016-01-01

    Objective The aim of this study was to compare the catastrophic health expenditure (CHE) prevalence and its determinants between empty-nest and non-empty-nest elderly households. Setting Shandong province of China. Participants A total of 2761 elderly households are included in the analysis. Results CHE incidence among elderly households was 44.9%. The CHE incidence of empty-nest singles (59.3%, p=0.000, OR=3.19) and empty-nest couples (52.9%, p=0.000, OR=2.45) are both statistically higher than that of non-empty-nest elderly households (31.4%). An inverse association was observed between CHE incidence and income level in all elderly household types. Factors including 1 or more household elderly members with non-communicable chronic diseases in the past 6 months, 1 or more elderly household members being hospitalised in the past year and lower household income, are significant risk factors for CHE in all 3 household types (p<0.05). Health insurance status was found to be a significant determinant of CHE among empty-nest singles and non-empty-nest households (p<0.05). Conclusions CHE incidence among elderly households is high in China. Empty-nest households are at higher risk for CHE than non-empty-nest households. Based on these findings, we suggest that special insurance be developed to broaden the coverage of health services and heighten the reimbursement rate for empty-nest elderly in the existing health insurance schemes. Financial and social protection interventions are also essential for identified at-risk subgroups among different types of elderly households. PMID:27381206

  3. Fish intake and ovarian cancer risk: a meta-analysis of 15 case-control and cohort studies.

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    Pei-yue Jiang

    Full Text Available BACKGROUND: Previous epidemiological studies have shown that fish consumption may modify the risk of ovarian cancer. However, these studies yielded controversial results. The present meta-analysis was undertaken to evaluate the relationship between fish intake and ovarian cancer risk. METHODS: A literature search was carried out using Pubmed, Embase, and Cochrane Library Central database for all relevant studies up to August 2013. We pooled the relative risks (RR from individual studies using fixed-effect or random-effect model, and carried out heterogeneity and publication bias analyses. RESULTS: A total of 15 (ten case-control, and five cohort studies were included in the present meta-analysis, representing data for 889,033 female subjects and 6,087 ovarian cancer cases. We found that total fish intake was not significantly associated with the risk of ovarian cancer among cohort studies (RR = 1.04 95% CI [0.89, 1.22] as well as case-control studies (RR = 0.90, 95% CI [0.73,1.12]. There was no evidence of publication bias as suggested by Begg's test (P = 0.55 and Egger's test(P = 0.29. CONCLUSIONS: The present meta-analysis showed that total fish consumption was not significantly associated with the risk of ovarian cancer. Further analysis on different fish species and food preparation methods should be conducted in future studies.

  4. Source attribution of human campylobacteriosis using a meta-analysis of case-control studies of sporadic infections

    DEFF Research Database (Denmark)

    Coutinho Calado Domingues, Ana Rita; Pires, Sara Monteiro; Hisham Beshara Halasa, Tariq;

    2012-01-01

    important sources of human disease is essential for prioritizing food safety interventions and setting public health goals. Numerous case-control studies of sporadic infections of campylobacteriosis have been published. These studies investigated a variety of potential risk factors for disease, often using...... different methodologies and settings. Systematic reviews (SRs) consist of a formal process for literature review focused on a specific research question, and include the identification of relevant literature, quality assessment of relevant studies, summarization or statistical analysis of data...... sources, and direct contact with farm animals were significant risk factors for campylobacteriosis. Sub-analyses by geographical region, age group, and study period were performed, and differences were discussed....

  5. Vaccines are not associated with autism: an evidence-based meta-analysis of case-control and cohort studies.

    Science.gov (United States)

    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.

  6. Thymidylate synthase genetic polymorphisms and cancer risk:a meta-analysis of 37 case-control studies

    Institute of Scientific and Technical Information of China (English)

    TANG Jian; WANG Pei-pei; ZHUANG Yan-yan; CHEN Wen-jie; HUANG Feng-ting; ZHANG Shi-neng

    2012-01-01

    Background Several studies have evaluated the association between polymorphisms of thymidylate synthase (TS)and cancer risk in diverse populations but with conflicting results.By pooling the relatively small samples in each study,it is possible to evaluate the association using a meta-analysis.Methods A comprehensive search was conducted to identify all case-control studies on TS on a 28-bp tandem repeats in 5′untranslated region (5′UTR) and a 6-bp insertion (ins) and deletion (del) mutation in 3′UTR of the gene and cancer risk.Meta-analysis was conducted using a fixed and random effect model.Results Our meta-analysis on a total of 13307 cancer cases and 18226 control subjects from 37 published case-control studies showed no significant association between the risk of cancer and the 5′UTR 28-bp tandem repeats polymorphism (3R/3R vs.2R/2R:OR=1.06,95% CI,0.93-1.20) or the 3′UTR 6-bp ins/del polymorphism (del6/del6 vs.ins6/ins6:0R=0.93,95% CI,0.81-1.08) with significant between-study heterogeneity.In the cancer type- and ethnic subgroup-stratification analyses,we did not find any association between TS polymorphisms and cancer risk either.Conclusion TS 5′UTR 28-bp tandem repeats and 3′UTR 6-bp ins/del polymorphisms may not be associated with cancer risk.

  7. 吸烟与原发性肝癌关系的巢式病例对照研究%Cigarette smoking and primary liver cancer risk: a nested case-control study in Shanghai

    Institute of Scientific and Technical Information of China (English)

    张薇; 高玉堂; 王学励; 张玉兰; Jian-min Yuan

    2009-01-01

    Objective To evaluate the association between cigarette smoking and risk of primary liver cancer (PLC) among middle-aged and elderly men in urban Shanghai. Methods A nested case- control study was conducted based on a cohort of 18 244 men who were 45-64 years of age in 1986-1989 and had no history of cancer at recruitment in Shanghai. As of Dec 31, 2000, a total of 213 incident cases of PLC were identified. 1094 matched controls were randomly selected among the cohort subjects who were free of cancer and alive at the time of cancer diagnosis of the index case. The matching criteria were date of birth (within 2 years), date of biospsy specimen collection (within 1 month), and neighborhood of residence at recruitment. Conditional logistic regression models were used to estimate adjusted odds ratios (ORs) and their corresponding 95% confidence intervals (CIs). Results After controlling for potential confounders, cigarette smoking (ever vs. never) was associated with risk of PLC (OR=1.91; 95% CI:1.28-2.86). Risk of PLC increased with increasing number of cigarettes smoked per day, as well as duration of cigarette smoking,pack-years of cigarettes consumed over lifetime and earlier age started smoking. The ORs were 2.16 (95%CI=1.37~3.40), 2.14(95%CI=1.18~3.87), 2.12(95%CI=1.21~3.74) and 2.57 (95% CI=1.50~4.40) for men who smoked 20 cigarettes or more daily, smoked for 40 or more years, consumed more than 37 pack-years of cigarettes, and began smoking before 20 years of age, respectively. Conclusion This study confirms that cigarette smoking is an independent risk factor for primary liver cancer among males in Shanghai.%目的 分析吸烟与上海市区中老年男性原发性肝癌的关系.方法 应用巢式病例对照研究方法,对一个18 244名男性队列随访11年,以队列中213例新发肝癌患者作为病例组,按照患者年龄、采样日期、同居住区等配对条件,从队列中随机抽取1094名健康人作为对照组.使用配

  8. Evaluation of the landscape surrounding northern bobwhite nest sites: A multiscale analysis

    Science.gov (United States)

    White, C.G.; Schweitzer, Sara H.; Moore, C.T.; Parnell, I.B.; Lewis-Weis, L.A.

    2005-01-01

    Implementation of the Conservation Reserve Program (CRP) altered the interspersion and abundance of patches of different land-cover types in landscapes of the southeastern United States. Because northern bobwhites (Colinus virginianus) are experiencing significant population declines throughout most of their range, including the Southeast, it is critical to understand the impacts of landscape-scale changes in habitat on their reproductive rates. Our objective was to identify components of landscape structure important in predicting nest site selection by bobwhites at different spatial scales in the Upper Coastal Plain of Georgia. We used a Geographic Information System (GIS) and spatial analysis software to calculate metrics of landscape structure near bobwhite nest sites. Logistic regression was used to model the relationship of nest sites to structure within the surrounding landscape at 4 spatial scales. We found that patch density and open-canopy planted pine were consistently important predictor variables at multiple scales, and other variables were important at various scales. The density of different patch types could be increased by thinning rows of pines in large monotypic stands of closed-canopy planted pine stands. Thinning and creating openings in CRP pine plantations should provide increased nesting opportunities for bobwhites. We interpret the support for other variables in our analysis as an indication that various patch configuration lead to different combinations of landscape structure that provide an acceptable range of habitat conditions for bobwhites.

  9. Occupational exposures to solvents and lead as risk factors for Alzheimer's disease: A collaborative re-analysis of case-control studies

    NARCIS (Netherlands)

    A.B. Graves; C.M. van Duijn (Cock); V. Chandra; L. Fratiglioni (Laura); A. Heyman; A.F. Jorm; E. Kokmen (Emre); K. Kondo; J.A. Mortimer; W.A. Rocca; S.L. Shalat; H. Soininen; A. Hofman (Albert)

    1991-01-01

    textabstractA meta-analysis, involving the secondary analysis of original data from 11 case-control studies of Alzheimer's disease, is presented for occupational exposures to solvents and lead. Three studies had data on occupational exposure to solvents. Among cases, 21.3% were reported to have been

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

    NARCIS (Netherlands)

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

    2008-01-01

    Introduction We estimated the cost effectiveness of concomitant proton pump inhibitors (PPIs) in relation to the occurrence of non-steroidal anti-inflammatory drug (NSAID) ulcer complications. Methods This study was linked to a nested case-control study. Patients with NSAID ulcer complications were

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

    NARCIS (Netherlands)

    Vonkeman, H.E.; Braakman-Jansen, L.M.A.; Klok, R.M.; Postma, M.J.; Brouwers, J.R.B.J.; van de Laar, M.A.F.J.

    2009-01-01

    Introduction We estimated the cost effectiveness of concomitant proton pump inhibitors (PPIs) in relation to the occurrence of non-steroidal anti-inflammatory drug (NSAID) ulcer complications. Methods This study was linked to a nested case-control study. Patients with NSAID ulcer complications were

  12. A method for detecting epistasis in genome-wide studies using case-control multi-locus association analysis

    Directory of Open Access Journals (Sweden)

    Galan Jose

    2008-07-01

    Full Text Available Abstract Background The difficulty in elucidating the genetic basis of complex diseases roots in the many factors that can affect the development of a disease. Some of these genetic effects may interact in complex ways, proving undetectable by current single-locus methodology. Results We have developed an analysis tool called Hypothesis Free Clinical Cloning (HFCC to search for genome-wide epistasis in a case-control design. HFCC combines a relatively fast computing algorithm for genome-wide epistasis detection, with the flexibility to test a variety of different epistatic models in multi-locus combinations. HFCC has good power to detect multi-locus interactions simulated under a variety of genetic models and noise conditions. Most importantly, HFCC can accomplish exhaustive genome-wide epistasis search with large datasets as demonstrated with a 400,000 SNP set typed on a cohort of Parkinson's disease patients and controls. Conclusion With the current availability of genetic studies with large numbers of individuals and genetic markers, HFCC can have a great impact in the identification of epistatic effects that escape the standard single-locus association analyses.

  13. Analysis of eight genes modulating interferon gamma and human genetic susceptibility to tuberculosis: a case-control association study

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    Hoal Eileen G

    2010-06-01

    Full Text Available Abstract Background Interferon gamma is a major macrophage-activating cytokine during infection with Mycobacterium tuberculosis, the causative pathogen of tuberculosis, and its role has been well established in animal models and in humans. This cytokine is produced by activated T helper 1 cells, which can best deal with intracellular pathogens such as M. tuberculosis. Based on the hypothesis that genes which regulate interferon gamma may influence tuberculosis susceptibility, we investigated polymorphisms in eight candidate genes. Methods Fifty-four polymorphisms in eight candidate genes were genotyped in over 800 tuberculosis cases and healthy controls in a population-based case-control association study in a South African population. Genotyping methods used included the SNPlex Genotyping System™, capillary electrophoresis of fluorescently labelled PCR products, TaqMan® SNP genotyping assays or the amplification mutation refraction system. Single polymorphisms as well as haplotypes of the variants were tested for association with TB using statistical analyses. Results A haplotype in interleukin 12B was nominally associated with tuberculosis (p = 0.02, but after permutation testing, done to assess the significance for the entire analysis, this was not globally significant. In addition a novel allele was found for the interleukin 12B D5S2941 microsatellite. Conclusions This study highlights the importance of using larger sample sizes when attempting validation of previously reported genetic associations. Initial studies may be false positives or may propose a stronger genetic effect than subsequently found to be the case.

  14. Analysis of plasma lipid peroxidation and antioxidant enzymes status in patients of oral leukoplakia: A case control study

    Science.gov (United States)

    Srivastava, Kumar Chandan; Shrivastava, Deepti

    2016-01-01

    Aims and Objectives: Imbalances between the oxidant-antioxidant status have been implicated in the pathogenesis of several diseases, including oral cancer. Mostly, all oral cancer lesions are preceded by a stage of premalignancy. The present study aims to evaluate lipid peroxidation and antioxidant status in the venous blood of patients with different clinicopathologic stages of leukoplakia. Materials and Methods: A case control study was designed with the inclusion of 20 new cases of histopathologically proven leukoplakia of various clinical stages along with an equal number of positive and negative control individuals. The concentrations of thiobarbituric acid reactive substances and the activities of the antioxidant enzymes, namely superoxide dismutase, reduced glutathione, glutathione peroxidase, and catalase, were estimated in plasma using spectrophotometric methods. The data are expressed as mean ± SD. The statistical comparisons between and within the study groups were performed by one-way analysis of variance followed by post hoc analysis. Karl Pearson correlation was performed for the biochemical parameters within the group and between the groups. For statistically significant correlations, simple linear regression was performed. Results: Significant enhanced lipid peroxidation (P leukoplakia patients compared with positive as well as negative controls. Accordingly, significant (P < 0.001) pattern of progression in thiobarbituric acid reactive substances levels was observed at various clinical stages among patients of both control groups. Among enzymes, glutathione showed significant (P < 0.001) reduction along the stages on comparison with two control groups. Conclusion: Enhanced lipid peroxidation and compromised antioxidant defense in plasma indicate the development of oxidative stress. Among the antioxidant enzymes, reduced glutathione and glutathione Pperoxidase may play a decisive role in malignant transformation. PMID:28217539

  15. Risk of multiple myeloma in rheumatoid arthritis: a meta-analysis of case-control and cohort studies.

    Directory of Open Access Journals (Sweden)

    Kaini Shen

    Full Text Available multiple myeloma is a malignant neoplasm of plasma cells mainly affecting elderly patients. Despite the wealth of information available on therapeutic strategies, the etiology and pathogenesis of myeloma remain unclear. In the current study, a meta-analysis was conducted to assess the possible association between rheumatoid arthritis and myeloma.a literature search was conducted with PubMed, EMBASE and Web of Science for relevant studies published by December 25, 2013. Additionally, we searched annual meeting abstracts of the American Society of Hematology from 2004 to 2013. Only original studies that investigated the association between rheumatoid arthritis and myeloma were included. In total, 8 case-control and 10 cohort studies were identified for analysis.the meta-estimate of the association between rheumatoid arthritis and myeloma was 1.14 (95% CI, 0.97-1.33 overall, with significant heterogeneity among studies. The relationship between myeloma and other autoimmune diseases was additionally examined from available data. Our results showed that myeloma risk is increased 1.31 to 1.65-fold in pernicious anemia and 1.36 to 2.30-fold in ankylosing spondylitis patients.Rheumatoid arthritis does not appear to alter the risk of myeloma, while between-study heterogeneity analyses suggest caution in the interpretation of results. Pernicious anemia and ankylosing spondylitis may be potential risk factors for myeloma development. Future large-scale epidemiological studies with reliable exposure biomarkers are necessary to establish the possible contribution of autoimmune disorders to multiple myeloma.

  16. Homocysteine and coronary heart disease: meta-analysis of MTHFR case-control studies, avoiding publication bias.

    Directory of Open Access Journals (Sweden)

    Robert Clarke

    2012-02-01

    Full Text Available 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.

  17. Reduced Serum Level of Interleukin-10 is Associated with Cerebral Infarction: A Case-Control and Meta-Analysis Study.

    Science.gov (United States)

    Zhu, Yifei; Yang, Haiqing; Diao, Zengyan; Li, Yi; Yan, Chuanzhu

    2016-05-01

    IL-10 expression limits inflammation and restricts the size of CNS damage from stroke. In this study, we examined the correlation between cerebral infarction (CI) and serum levels of interleukin-10 (IL-10) using a combination of case-control study and meta-analysis of published data, with an aim of understanding the relevance of serum IL-10 levels to CI development. This study enrolled a total of 169 CI patients admitted to the Second Hospital of Hebei Medical University between May 2011 and November 2014. During the same period, a group of 145 individuals were recruited at the same hospital as healthy controls after thorough physical examination. Serum IL-10 levels were measured by enzyme-linked immunosorbent assay (ELISA). SPSS 19.0 (IBM, 2010, Chicago, IL, USA) and Comprehensive Meta-Analysis 2.0 (CMA 2.0) software were used for data analysis. Serum levels of IL-10 (pg/mL) were significantly lower in CI patients when compared to healthy controls (15.36 ± 3.21 vs. 21.64 ± 5.17, t = 13.12, P IL-10 (pg/mL) compared to healthy controls (LAAS 14.77 ± 5.21, CEI 15.25 ± 5.10, LAC 16.58 ± 4.92, all P IL-10 levels when pair-wise comparisons were made between these three clinical subtypes of CI (all P > 0.05). Logistic regression analysis indicated that, with the exception of triglyceride (TG) and uric acid (UA) levels (both P > 0.05), the other seven parameters, including fasting blood glucose (FPG), total cholesterol, low-density lipoprotein (LDL), high-density lipoprotein (HDL), creatinine (Cr), systolic blood pressure (SBP), and diastolic blood pressure (DBP), strongly correlated with CI development (all P IL-10 levels and CI (SMD = 1.797, 95% CI 0.785~2.810, P = 0.001). Subgroup analysis based on country showed that low serum levels of IL-10 may be the major risk factor for CI in Croatia (SMD = 2.961, 95% CI 2.480~3.443, P IL-10 serum levels and CI displayed negative relationship in Asians (SMD = 2.522, 95% CI 0.468~4.576, P = 0.016) but not in Caucasians (P > 0

  18. Chronic myelogenous leukemia and benzene exposure: a systematic review and meta-analysis of the case-control literature.

    Science.gov (United States)

    Lamm, Steven H; Engel, Arnold; Joshi, Kiran P; Byrd, Daniel M; Chen, Rusan

    2009-12-10

    Benzene exposure is well demonstrated as a cause of acute myelogenous leukemia, but not of chronic myelogenous leukemia. Previous literature reviews based on case series and cohort studies have not shown an association. We have now conducted a literature search for case-control studies that examine the association between benzene exposure and chronic myelogenous leukemia. Six case-control studies have been found. These derive from occupational groups, cancer registries, and a clinical laboratory. Their exposure ascertainments are all based on job histories, job-exposure matricies, or industrial hygiene data. The odds ratios (ORs) for individual studies range from 0.73 to 1.2. The pooled OR is 1.003 with 95% confidence interval (CI) of 0.94-1.07 (p=0.98) for both a fixed effects model and a random effects model. The case-control literature indicates that chronic myelogenous leukemia does not appear to be related to benzene exposure.

  19. Motor vehicle crashes in diabetic patients with tight glycemic control: a population-based case control analysis.

    Directory of Open Access Journals (Sweden)

    Donald A Redelmeier

    2009-12-01

    Full Text Available BACKGROUND: Complications from diabetes mellitus can compromise a driver's ability to safely operate a motor vehicle, yet little is known about whether euglycemia predicts normal driving risks among adults with diabetes. We studied the association between glycosylated hemoglobin (HbA1c and the risk of a motor vehicle crash using a population-based case control analysis. METHODS AND FINDINGS: We identified consecutive drivers reported to vehicle licensing authorities between January 1, 2005 to January 1, 2007 who had a diagnosis of diabetes mellitus and a HbA1c documented. The risk of a crash was calculated taking into account potential confounders including blood glucose monitoring, complications, and treatments. A total of 57 patients were involved in a crash and 738 were not involved in a crash. The mean HbA1c was lower for those in a crash than controls (7.4% versus 7.9%, unpaired t-test, p = 0.019, equal to a 26% increase in the relative risk of a crash for each 1% reduction in HbA1c (odds ratio = 1.26, 95% confidence interval 1.03-1.54. The trend was evident across the range of HbA1c values and persisted after adjustment for measured confounders (odds ratio = 1.25, 95% confidence interval 1.02-1.55. The two other significant risk factors for a crash were a history of severe hypoglycemia requiring outside assistance (odds ratio = 4.07, 95% confidence interval 2.35-7.04 and later age at diabetes diagnosis (odds ratio per decade = 1.29, 95% confidence interval 1.07-1.57. CONCLUSIONS: In this selected population, tighter glycemic control, as measured by the HbA1c, is associated with an increased risk of a motor vehicle crash.

  20. 4-nitroquinoline-1-oxide-induced mutagen sensitivity and risk of cutaneous melanoma: a case-control analysis.

    Science.gov (United States)

    Wang, Li-E; Li, Chunying; Xiong, Ping; Gershenwald, Jeffrey E; Prieto, Victor G; Duvic, Madeleine; Lee, Jeffrey E; Grimm, Elizabeth A; Hsu, Tao C; Wei, Qingyi

    2016-04-01

    Mutagen sensitivity assay, which measures the enhanced cellular response to DNA damage induced in vitro by mutagens/carcinogens, has been used in the study of cancer susceptibility. 4-Nitroquinoline-1-oxide (4-NQO), an ultraviolet (UV) radiation-mimetic chemical, can produce chromosomal breaks in mammalian cells and induce cancer. Given the potential role of 4-NQO as the experimental mutagen substituting for UV as the etiological carcinogen of cutaneous melanoma (CM), we tested the hypothesis that cellular sensitivity to 4-NQO is associated with the risk of developing CM in a case-control study of 133 patients with primary CM and 176 cancer-free controls. Short-term blood cultures were treated with 4-NQO at a final concentration of 10 μmol/l for 24 h and scored chromatid breaks in 50 well-spread metaphases. Multivariate logistic regression was used to calculate odds ratios and 95% confidence intervals. We found that the log-transformed frequency of chromatid breaks was significantly higher in 133 patients than in 176 controls (P=0.004) and was associated with an increased risk for CM (adjusted odds ratio=1.78, 95% confidence interval: 1.12-2.84) after adjustment for age and sex. Moreover, as the chromatid break values increased, the risk for CM increased in a dose-dependent manner (P(trend)=0.003). Further analysis explored a multiplicative interaction between the sensitivity to 4-NQO and a family history of skin cancer (P(interaction)=0.004) on the risk of CM. Therefore, our findings suggest that sensitivity to 4-NQO may be a risk factor for the risk of CM, which is more sensitive than UV-induced chromotid breaks.

  1. Alcohol-related breast cancer in postmenopausal women - effect of CYP19A1, PPARG and PPARGC1A polymorphisms on female sex-hormone levels and interaction with alcohol consumption and NSAID usage in a nested case-control study and a randomised controlled trial

    DEFF Research Database (Denmark)

    Kopp, Tine Iskov; Jensen, Ditte Marie; Ravn-Haren, Gitte;

    2016-01-01

    19A1 is associated with risk of BC in a case-control study group nested within the Danish "Diet, Cancer and Health" cohort (ncases = 687 and ncontrols = 687) and searched for gene-gene interaction between CYP19A1 and PPARGC1A, and CYP19A1 and PPARG, and gene-alcohol and gene-NSAID interactions....... Association between the CYP19A1 polymorphisms and hormone levels was also examined among 339 non-HRT users. Incidence rate ratios were calculated based on Cox' proportional hazards model. Furthermore, we performed a pilot randomised controlled trial to determine the effect of the PPARG Pro(12)Ala polymorphism......Alcohol consumption is associated with increased risk of breast cancer (BC), and the underlying mechanism is thought to be sex-hormone driven. In vitro and observational studies suggest a mechanism involving peroxisome proliferator-activated receptor gamma (PPARγ) in a complex with peroxisome...

  2. Familial aggregation of Alzheimer's disease and related disorders: A collaborative re-analysis of case-control studies

    NARCIS (Netherlands)

    C.M. van Duijn (Cock); D.G. Clayton (David); V. Chandra; L. Fratiglioni (Laura); A.B. Graves; A. Heyman; A.F. Jorm; E. Kokmen (Emre); K. Kondo; J.A. Mortimer; W.A. Rocca; S.L. Shalat; H. Soininen; A. Hofman (Albert)

    1991-01-01

    textabstractCase-control studies of Alzheimer's disease were re-analysed to examine the association of Alzheimer's disease with family history in first degree relatives of dementia, Down's syndrome and Parkinson's disease. Overall, the relative risk of Alzheimer's disease for those with at least one

  3. Risk factors for Alzheimer's disease: Overview of the EURODEM collaborative re-analysis of case-control studies

    NARCIS (Netherlands)

    C.M. van Duijn (Cock); Th. Stijnen (Theo); A. Hofman (Albert)

    1991-01-01

    textabstractStudies of risk factors for Alzheimer's disease have been hampered by low statistical power. The data from 11 case-control studies were pooled and re-analysed to evaluate the evidence for the association of Alzheimer's disease with family history of dementia and related disorders, parent

  4. Risk factors for campylobacteriosis of chicken, ruminant, and environmental origin: a combined case-control and source attribution analysis

    NARCIS (Netherlands)

    Mughini Gras, L.; Smid, J.H.; Wagenaar, J.A.; de Boer, A.G.; Havelaar, A.H.; Friesema, I.H.M.; French, N.P.; Busani, L.; van Pelt, W.

    2012-01-01

    BACKGROUND Campylobacteriosis contributes strongly to the disease burden of food-borne pathogens. Case-control studies are limited in attributing human infections to the different reservoirs because they can only trace back to the points of exposure, which may not point to the original reservoirs be

  5. Risk Factors for Campylobacteriosis of Chicken, Ruminant, and Environmental Origin: A Combined Case-Control and Source Attribution Analysis

    NARCIS (Netherlands)

    Gras, L.M.; Smid, J.H.; Wagenaar, J.A.; Boer, de A.G.; Havelaar, A.H.; Friesema, I.H.M.; French, N.P.; Busani, L.; Pelt, van W.

    2012-01-01

    Background: Campylobacteriosis contributes strongly to the disease burden of food-borne pathogens. Case-control studies are limited in attributing human infections to the different reservoirs because they can only trace back to the points of exposure, which may not point to the original reservoirs b

  6. Chlamydia trachomatis and invasive cervical cancer: a pooled analysis of the IARC multicentric case-control study.

    NARCIS (Netherlands)

    Smith, J.S.; Bosetti, C; Munoz, N.; Herrero, R; Bosch, F.X.; Eluf-Neto, J; Meijer, C.J.L.M.; Brule, van den AJ; Franceschi, S; Peeling, RW

    2004-01-01

    To determine whether Chlamydia trachomatis infection is consistently associated with an increased risk of invasive cervical carcinoma (ICC) after accounting for the strong effect of human papillomavirus (HPV) infection, a case-control study of 1,238 cases of ICC and 1,100 control women from 7 countr

  7. A pooled analysis of case-control studies of thyroid cancer. VII. Cruciferous and other vegetables (International)

    NARCIS (Netherlands)

    Bosetti, C; Negri, E; Kolonel, L; Ron, E; Franceschi, S; Preston-Martin, S; McTiernan, A; Dal Maso, L; Mark, SD; Mabuchi, K; Land, C; Jin, F; Wingren, G; Galanti, MR; Hallquist, A; Glattre, E; Lund, E; Levi, F; Linos, D; La Vecchia, C

    2002-01-01

    Objective: To investigate the association between cruciferous and other vegetables and thyroid cancer risk we systematically reanalyzed the original data from 11 case-control studies conducted in the US, Asia, and Europe. Methods: A total of 2241 cases (1784 women, 457 men) and 3716 controls (2744 w

  8. The MTR 2756A>G polymorphism and maternal risk of birth of a child with Down syndrome: a case-control study and a meta-analysis.

    Science.gov (United States)

    Coppedè, Fabio; Bosco, Paolo; Lorenzoni, Valentina; Migheli, Francesca; Barone, Concetta; Antonucci, Ivana; Stuppia, Liborio; Romano, Corrado; Migliore, Lucia

    2013-12-01

    Methionine synthase (MTR) is required for the conversion of homocysteine (hcy) to methionine in the one-carbon metabolic pathway. Previous studies investigating a common MTR 2756A>G polymorphism as a maternal risk factor for the birth of a child with Down syndrome (DS) are conflicting and limited by small case-control cohorts, and its contribution to circulating hcy levels is still debated. We performed a large case-control study and a meta-analysis of the literature to further address the role of MTR 2756A>G as a maternal risk factor for the birth of a child with DS. 286 mothers of a DS child (MDS) and 305 control mothers of Italian origin were included in the case-control study. Genotyping was performed by means of PCR/RFLP technique. Data on circulating levels of hcy, folates, and vitamin B12 were available for 189 MDS and 194 control mothers. The meta analysis of previous and present data involved a total of 8 studies (1,171 MDS and 1,402 control mothers). Both the case-control study and the meta-analysis showed no association of MTR 2756A>G with the maternal risk of birth of a child with DS (OR = 1.15; 95 % CI 0.85-1.55, and OR = 1.08; 95 % CI 0.93-1.25, respectively), even after stratification of the overall data available for the meta-analysis into ethnic groups. No association of the studied polymorphism with circulating levels of hcy, folates, and vitamin B12 was observed. Present data do not support a role for MTR 2756A>G as independent maternal risk factor for a DS birth.

  9. The genetic variant on chromosome 10p14 is associated with risk of colorectal cancer: results from a case-control study and a meta-analysis.

    Directory of Open Access Journals (Sweden)

    Qin Qin

    Full Text Available BACKGROUND: A common single nucleotide polymorphism (SNP, rs10795668, located at 10p14, was first identified to be significantly associated with risk of colorectal cancer (CRC by a genome-wide association study (GWAS in 2008; however, another GWAS and following replication studies yielded conflicting results. METHODS: We conducted a case-control study of 470 cases and 475 controls in a Chinese population and then performed a meta-analysis, integrating the current study and 9 publications to evaluate the association between rs10795668 and CRC risk. Heterogeneity among studies and publication bias were assessed by the χ²-based Q statistic test and Egger's test, respectively. RESULTS: In the case-control study, significant association between the SNP and CRC risk was observed, with per-A-allele OR of 0.71 (95%CI: 0.54-0.94, P = 0.017. The following meta-analysis further confirmed the significant association, with per-A-allele OR of 0.91 (95%CI: 0.89-0.93, P(heterogeneity >0.05 in European population and 0.86 (95%CI: 0.78-0.96, P(heterogeneity <0.05 in Asian population. Besides, sensitivity analyses and publication bias assessment indicated the robust stability and reliability of the results. CONCLUSIONS: Results from our case-control study and the followed meta-analysis confirmed the significant association of rs10795668 with CRC risk.

  10. Molecular analysis of single oocyst of Eimeria by whole genome amplification (WGA) based nested PCR.

    Science.gov (United States)

    Wang, Yunzhou; Tao, Geru; Cui, Yujuan; Lv, Qiyao; Xie, Li; Li, Yuan; Suo, Xun; Qin, Yinghe; Xiao, Lihua; Liu, Xianyong

    2014-09-01

    PCR-based molecular tools are widely used for the identification and characterization of protozoa. Here we report the molecular analysis of Eimeria species using combined methods of whole genome amplification (WGA) and nested PCR. Single oocyst of Eimeria stiedai or Eimeriamedia was directly used for random amplification of the genomic DNA with either primer extension preamplification (PEP) or multiple displacement amplification (MDA), and then the WGA product was used as template in nested PCR with species-specific primers for ITS-1, 18S rDNA and 23S rDNA of E. stiedai and E. media. WGA-based PCR was successful for the amplification of these genes from single oocyst. For the species identification of single oocyst isolated from mixed E. stiedai or E. media, the results from WGA-based PCR were exactly in accordance with those from morphological identification, suggesting the availability of this method in molecular analysis of eimerian parasites at the single oocyst level. WGA-based PCR method can also be applied for the identification and genetic characterization of other protists.

  11. Risk factors for campylobacteriosis of chicken, ruminant, and environmental origin: a combined case-control and source attribution analysis.

    Directory of Open Access Journals (Sweden)

    Lapo Mughini Gras

    Full Text Available BACKGROUND: Campylobacteriosis contributes strongly to the disease burden of food-borne pathogens. Case-control studies are limited in attributing human infections to the different reservoirs because they can only trace back to the points of exposure, which may not point to the original reservoirs because of cross-contamination. Human Campylobacter infections can be attributed to specific reservoirs by estimating the extent of subtype sharing between strains from humans and reservoirs using multilocus sequence typing (MLST. METHODOLOGY/PRINCIPAL FINDINGS: We investigated risk factors for human campylobacteriosis caused by Campylobacter strains attributed to different reservoirs. Sequence types (STs were determined for 696 C. jejuni and 41 C. coli strains from endemic human cases included in a case-control study. The asymmetric island model, a population genetics approach for modeling Campylobacter evolution and transmission, attributed these cases to four putative animal reservoirs (chicken, cattle, sheep, pig and to the environment (water, sand, wild birds considered as a proxy for other unidentified reservoirs. Most cases were attributed to chicken (66% and cattle (21%, identified as the main reservoirs in The Netherlands. Consuming chicken was a risk factor for campylobacteriosis caused by chicken-associated STs, whereas consuming beef and pork were protective. Risk factors for campylobacteriosis caused by ruminant-associated STs were contact with animals, barbecuing in non-urban areas, consumption of tripe, and never/seldom chicken consumption. Consuming game and swimming in a domestic swimming pool during springtime were risk factors for campylobacteriosis caused by environment-associated STs. Infections with chicken- and ruminant-associated STs were only partially explained by food-borne transmission; direct contact and environmental pathways were also important. CONCLUSION/SIGNIFICANCE: This is the first case-control study in which risk

  12. Detection of HLA-DRB1 microchimerism using nested polymerase chain reaction and single-strand conformation polymorphism analysis.

    Science.gov (United States)

    Song, Eun Young; Chung, Hye Yoon; Joo, Shin Young; Roh, Eun Youn; Seong, Moon-Woo; Shin, Yunsu; Park, Myoung Hee

    2012-03-01

    For the detection of microchimerism, molecular methods detecting donor-specific HLA-DRB1 alleles in the recipient are most commonly used. Nested polymerase chain reaction sequence specific primer (nested PCR-SSP) methods widely used to increase the sensitivity of detection have been reported to give frequent false-positive reactions. We have developed a new method combining nested PCR with single-strand conformation polymorphism analysis (nested PCR-SSCP) and tested the 1 to 0.00001% level of microchimerism for 27 different HLA-DRB1 alleles. For most (26/27) of the HLA-DRB1 alleles tested, this method could detect 0.01 to 0.001% of microchimerism and its sensitivity was equal to or better than that of nested PCR-SSP tested in parallel. Its specificity was verified by visualizing particular DRB1-specific SSCP bands under test. Nested PCR-SSP indicated frequent false-positive reactions, mainly caused by nonspecific amplification of DRB3/B4/B5 alleles present in the major (recipient) DNAs. We have compared a real-time quantitative PCR for non-human leukocyte antigen (HLA) target (insertion/deletion marker) using a commercial kit (AlleleSEQR Chimerism assay), and its microchimerism detection sensitivity (around 0.1%) was 1 step (10 times) lower than that of nested PCR-SSP or -SSCP methods for HLA-DRB1 alleles. We validated that the newly designed nested PCR-SSCP affords good sensitivity and specificity and may be useful for studying microchimerism in clinical settings.

  13. The SNP rs931794 in 15q25.1 Is Associated with Lung Cancer Risk: A Hospital-Based Case-Control Study and Meta-Analysis.

    Directory of Open Access Journals (Sweden)

    Qi Wang

    Full Text Available Lung cancer is one of the most common human malignant diseases and the leading cause of cancer death worldwide. The rs931794, a SNP located in 15q25.1, has been suggested to be associated with lung cancer risk. Nevertheless, several genetic association studies yielded controversial results.A hospital-based case-control study involving 611 cases and 1062 controls revealed the variant of rs931794 was related to increased lung cancer risk. Stratified analyses revealed the G allele was significantly associated with lung cancer risk among smokers. Following meta-analysis including 6616 cases and 7697 controls confirmed the relevance of rs931794 variant with increased lung cancer risk once again. Heterogeneity should be taken into account when interpreting the consequences. Stratified analysis found ethnicity, histological type and genotyping method were not the sources of between-study heterogeneity. Further sensitivity analysis revealed that the study "Hsiung et al (2010" might be the major contributor to heterogeneity. Cumulative meta-analysis showed the trend was increasingly obvious with adding studies, confirming the significant association.Results from our current case-control study and meta-analysis offered insight of association between rs931794 and lung cancer risk, suggesting the variant of rs931794 might be related with increased lung cancer risk.

  14. Alcohol-related breast cancer in postmenopausal women - effect of CYP19A1, PPARG and PPARGC1A polymorphisms on female sex-hormone levels and interaction with alcohol consumption and NSAID usage in a nested case-control study and a randomised controlled trial

    DEFF Research Database (Denmark)

    Kopp, Tine Iskov; Jensen, Ditte Marie; Ravn-Haren, Gitte;

    2016-01-01

    19A1 is associated with risk of BC in a case-control study group nested within the Danish "Diet, Cancer and Health" cohort (ncases = 687 and ncontrols = 687) and searched for gene-gene interaction between CYP19A1 and PPARGC1A, and CYP19A1 and PPARG, and gene-alcohol and gene-NSAID interactions......Alcohol consumption is associated with increased risk of breast cancer (BC), and the underlying mechanism is thought to be sex-hormone driven. In vitro and observational studies suggest a mechanism involving peroxisome proliferator-activated receptor gamma (PPARγ) in a complex with peroxisome...... and the PPARγ stimulator Ibuprofen on sex-hormone levels following alcohol intake in postmenopausal women (n = 25) using linear regression. Genetic variations in CYP19A1 were associated with hormone levels (estrone: P rs11070844 = 0.009, estrone sulphate: P rs11070844 = 0.01, P rs749292 = 0.004, P rs1062033 = 0...

  15. Functional analysis of the newly established plants induced by nesting gulls on Riou archipelago (Marseille, France)

    Science.gov (United States)

    Vidal, Eric; Médail, Frédéric; Tatoni, Thierry; Vidal, Patrick; Roche, Philip

    1998-06-01

    The recent population explosion of Yellow-legged gulls ( Larus cachinnans), nesting on the Riou archipelago, off Marseille (France), has perturbed the flora and the vegetation of this site. The present study consists of a functional approach to the newly established plant species through an analysis of some of their vital attributes. Small islets appear to be more affected by floristic turnover than larger islands. In some cases, more than 50 % of the current flora was not present 35 years ago. The newly established taxa show special adaptations to the severe ecological pressure induced by gull colonies and to the characteristics of the Mediterranean climate. These plant species are mostly therophytes or hemicryptophytes and have a ruderal or a stress-tolerant strategy. Gulls' contribution to propagule dispersal from the continent appears to be very slight, dispersal by wind being the prevalent mode.

  16. Risk factors associated with hantavirosis fatality: a regional analysis from a case-control study in Brazil

    Directory of Open Access Journals (Sweden)

    Maria Cristina Antunes Willemann

    2014-01-01

    Full Text Available Introduction: In Brazil, hantavirus cardiopulmonary syndrome (HCPS has a high lethality rate that varies by region. This study aimed to identify the risk factors associated with fatal hantavirosis. Methods: This study was a case-control study that included all laboratory confirmed cases of hantavirosis. The cases were stratified by the different Brazilian regions using data from the Notifiable Diseases Information System. “Cases” were patients who progressed to death, whereas “controls” were patients who were cured. The odds ratio (OR and the adjusted OR were calculated. Results: Overall, 158 cases and 281 controls were included in this study. In the Midwest region, the cases were 60% less likely to present with flank pain, and the time between the beginning of symptoms and death was shorter than the time between the beginning of symptoms and a cure. In the Southeast region, the cases were 60% less likely to present with thrombocytopenia or reside in rural areas compared to those who progressed to a cure. Additionally, the cases sought medical assistance, notification and investigation more quickly than the controls. In the Southern region, the cases that died were 70% less likely to be male compared to the controls. Conclusions: HCPS manifests with nonspecific symptoms, and there are few published studies related to the condition, so determining a patient's therapeutic strategy is difficult. This study presents findings from different Brazilian regions and highlights the need for further investigations to improve comprehension about regional risk factors associated with hantavirosis and to reduce morbimortality.

  17. The Role of Colour Doppler And Spectral Flow Analysis In Pregnancy Induced Hypertension: A Case Control Study

    Directory of Open Access Journals (Sweden)

    Hinal Bhagat

    2015-03-01

    Full Text Available Background: The use of Doppler ultrasound to study blood flow in Obstetrics is of major importance because fetal inaccessibility precludes many other methods of study of fetal circulation. This study was undertaken to assess the role of Doppler in management of Pregnancy induced Hypertension. Methodology: The present case-control study was conducted in the department of Radiology, Govt. Medical College and New Civil Hospital, Surat. Details of obstetric history, age, last menstrual date and underlying risk factor, Doppler study of umbilical artery, fetal middle cerebral artery, both maternal uterine arteries and Ductus venosus was done. Parameters in form of Resistive index (RI, Pulsatility index (PI and systolic/diastolic ratio (S/D of all four arteries were taken. Results: It was observed that 55% cases with pregnancy induced hypertension developed IUGR fetuses while 2% of the IUGR fetus was present in control group. There were 41 (54% cases with IUGR fetuses. Out of which 28 (68% cases with IUGR had fetoplacental Doppler abnormality. 13 cases had abnormally low PI of MCA with normal umbilical arterial Doppler indices, out of which 12 patients had abnormal fetal outcome. Conclusion: By examining the maternal vessels using Doppler ultrasound it is possible to determine, the risk of complication developing in the course of pregnancy long before clinical signs of preeclampsia appear so that therapeutic measures may be undertaken early. [Natl J Med Res 2015; 5(1.000: 57-60

  18. Total Exposure and Exposure Rate Effects for Alcohol and Smoking and Risk of Head and Neck Cancer: A Pooled Analysis of Case-Control Studies

    OpenAIRE

    Lubin, Jay H.; Purdue, Mark; Kelsey, Karl; Zhang, Zuo-Feng; Winn, Debbie; Wei, Qingyi; Talamini, Renato; Szeszenia-Dabrowska, Neonilia; Sturgis, Erich M.; Smith, Elaine; Shangina, Oxana; Schwartz, Stephen M.; Rudnai, Peter; Neto, Jose Eluf; Muscat, Joshua

    2009-01-01

    Although cigarette smoking and alcohol consumption increase risk for head and neck cancers, there have been few attempts to model risks quantitatively and to formally evaluate cancer site-specific risks. The authors pooled data from 15 case-control studies and modeled the excess odds ratio (EOR) to assess risk by total exposure (pack-years and drink-years) and its modification by exposure rate (cigarettes/day and drinks/day). The smoking analysis included 1,761 laryngeal, 2,453 pharyngeal, an...

  19. Triangular Nests!

    Science.gov (United States)

    Powell, R. I.

    2002-01-01

    Shows how integer-sided triangles can be nested, each nest having a single enclosing isosceles triangle. Brings to light what can be seen as a relatively simple generalization of Pythagoras' theorem, a result that should be readily accessible to many secondary school pupils. (Author/KHR)

  20. No association between the sigma receptor type 1 gene and schizophrenia: results of analysis and meta-analysis of case-control studies

    Directory of Open Access Journals (Sweden)

    Imamura Takaki

    2003-10-01

    Full Text Available Abstract 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.

  1. Nesting phenology of marine turtles: insights from a regional comparative analysis on green turtle (Chelonia mydas.

    Directory of Open Access Journals (Sweden)

    Mayeul Dalleau

    Full Text Available Changes in phenology, the timing of seasonal activities, are among the most frequently observed responses to environmental disturbances and in marine species are known to occur in response to climate changes that directly affects ocean temperature, biogeochemical composition and sea level. We examined nesting seasonality data from long-term studies at 8 green turtle (Chelonia mydas rookeries that include 21 specific nesting sites in the South-West Indian Ocean (SWIO. We demonstrated that temperature drives patterns of nesting seasonality at the regional scale. We found a significant correlation between mean annual Sea Surface Temperature (SST and dates of peak nesting with rookeries exposed to higher SST having a delayed nesting peak. This supports the hypothesis that temperature is the main factor determining peak nesting dates. We also demonstrated a spatial synchrony in nesting activity amongst multiple rookeries in the northern part of the SWIO (Aldabra, Glorieuses, Mohéli, Mayotte but not with the eastern and southern rookeries (Europa, Tromelin, differences which could be attributed to females with sharply different adult foraging conditions. However, we did not detect a temporal trend in the nesting peak date over the study period or an inter-annual relation between nesting peak date and SST. The findings of our study provide a better understanding of the processes that drive marine species phenology. The findings will also help to predict their ability to cope with climate change and other environmental perturbations. Despite demonstrating this spatial shift in nesting phenology, no trend in the alteration of nesting dates over more than 20 years was found.

  2. Nesting phenology of marine turtles: insights from a regional comparative analysis on green turtle (Chelonia mydas).

    Science.gov (United States)

    Dalleau, Mayeul; Ciccione, Stéphane; Mortimer, Jeanne A; Garnier, Julie; Benhamou, Simon; Bourjea, Jérôme

    2012-01-01

    Changes in phenology, the timing of seasonal activities, are among the most frequently observed responses to environmental disturbances and in marine species are known to occur in response to climate changes that directly affects ocean temperature, biogeochemical composition and sea level. We examined nesting seasonality data from long-term studies at 8 green turtle (Chelonia mydas) rookeries that include 21 specific nesting sites in the South-West Indian Ocean (SWIO). We demonstrated that temperature drives patterns of nesting seasonality at the regional scale. We found a significant correlation between mean annual Sea Surface Temperature (SST) and dates of peak nesting with rookeries exposed to higher SST having a delayed nesting peak. This supports the hypothesis that temperature is the main factor determining peak nesting dates. We also demonstrated a spatial synchrony in nesting activity amongst multiple rookeries in the northern part of the SWIO (Aldabra, Glorieuses, Mohéli, Mayotte) but not with the eastern and southern rookeries (Europa, Tromelin), differences which could be attributed to females with sharply different adult foraging conditions. However, we did not detect a temporal trend in the nesting peak date over the study period or an inter-annual relation between nesting peak date and SST. The findings of our study provide a better understanding of the processes that drive marine species phenology. The findings will also help to predict their ability to cope with climate change and other environmental perturbations. Despite demonstrating this spatial shift in nesting phenology, no trend in the alteration of nesting dates over more than 20 years was found.

  3. Association between interleukin-6 gene polymorphisms and rheumatoid arthritis in Chinese Han population: a case-control study and a meta-analysis.

    Science.gov (United States)

    Li, Feng; Xu, Jing; Zheng, Jiatian; Sokolove, Jeremy; Zhu, Kai; Zhang, Yuanchao; Sun, Hongsheng; Evangelou, Evangelos; Pan, Zhenglun

    2014-07-17

    The aim of this study was to investigate the possible association in the interleukin-6 (IL-6) gene with Rheumatoid arthritis (RA) in Chinese Han population from Shandong Province. Target regions of IL-6 gene were amplified by polymerase chain reaction (PCR) and genotyped. A logistic regression analysis was performed to detect potential associations in our case-control sample, the odd ratio(OR) and 95% confidence intervals(CIs) were calculated. Furthermore, we systematically tracked all the published studies in the field and performed a meta-analysis for the single nucleotide polymorphisms (SNPs) under study. 256 RA patients and 331 healthy controls were recruited into the case-control study. We found allele frequencies of rs1800795, rs1800797 and rs1474347 in RA patients differ from control subjects (P = 0.016, 0.024, 0.020, respectively). Significant difference was observed in haplotype frequencies of GCCGCT between RA patients and controls (P = 0.0001, OR = 4.066, 95%CI = 1.891 ~ 8.746), while GGCGCT frequencies was found lower in RA than controls (P = 0.006, OR = 0.669, 95%CI = 0.501 ~ 0.894). The results of the meta-analysis showed association polymorphism within the IL-6 promoter with RA. These findings suggest that rare IL-6 gene polymorphisms may associate with RA susceptibility in Han Chinese populations; however further studies are needed to assess the validity of the association of IL-6 with RA.

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

    Science.gov (United States)

    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 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.

  5. Analysis of 17,576 potentially functional SNPs in three case-control studies of myocardial infarction.

    Directory of Open Access Journals (Sweden)

    Dov Shiffman

    Full Text Available Myocardial infarction (MI is a common complex disease with a genetic component. While several single nucleotide polymorphisms (SNPs have been reported to be associated with risk of MI, they do not fully explain the observed genetic component of MI. We have been investigating the association between MI and SNPs that are located in genes and have the potential to affect gene function or expression. We have previously published studies that tested about 12,000 SNPs for association with risk of MI, early-onset MI, or coronary stenosis. In the current study we tested 17,576 SNPs that could affect gene function or expression. In order to use genotyping resources efficiently, we staged the testing of these SNPs in three case-control studies of MI. In the first study (762 cases, 857 controls we tested 17,576 SNPs and found 1,949 SNPs that were associated with MI (P<0.05. We tested these 1,949 SNPs in a second study (579 cases and 1159 controls and found that 24 SNPs were associated with MI (1-sided P<0.05 and had the same risk alleles in the first and second study. Finally, we tested these 24 SNPs in a third study (475 cases and 619 controls and found that 5 SNPs in 4 genes (ENO1, FXN (2 SNPs, HLA-DPB2, and LPA were associated with MI in the third study (1-sided P<0.05, and had the same risk alleles in all three studies. The false discovery rate for this group of 5 SNPs was 0.23. Thus, we have identified 5 SNPs that merit further examination for their potential association with MI. One of these SNPs (in LPA, has been previously shown to be associated with risk of cardiovascular disease in other studies.

  6. Association, characterisation and meta-analysis of SNPs linked to general reading ability in a German dyslexia case-control cohort

    Science.gov (United States)

    Müller, Bent; Wilcke, Arndt; Czepezauer, Ivonne; Ahnert, Peter; Boltze, Johannes; Kirsten, Holger; Friederici, Angela D.; Emmrich, Frank; Brauer, Jens; Wilcke, Arndt; Neef, Nicole; Boltze, Johannes; Skeide, Michael; Kirsten, Holger; Schaadt, Gesa; Müller, Bent; Kraft, Indra; Czepezauer, Ivonne; Dörr, Liane

    2016-01-01

    Dyslexia is a severe disorder in the acquisition of reading and writing. Several studies investigated the role of genetics for reading, writing and spelling ability in the general population. However, many of the identified SNPs were not analysed in case-control cohorts. Here, we investigated SNPs previously linked to reading or spelling ability in the general population in a German case-control cohort. Furthermore, we characterised these SNPs for functional relevance with in silico methods and meta-analysed them with previous studies. A total of 16 SNPs within five genes were included. The total number of risk alleles was higher in cases than in controls. Three SNPs were nominally associated with dyslexia: rs7765678 within DCDC2, and rs2038137 and rs6935076 within KIAA0319. The relevance of rs2038137 and rs6935076 was further supported by the meta-analysis. Functional profiling included analysis of tissue-specific expression, annotations for regulatory elements and effects on gene expression levels (eQTLs). Thereby, we found molecular mechanistical implications for 13 of all 16 included SNPs. SNPs associated in our cohort showed stronger gene-specific eQTL effects than non-associated SNPs. In summary, our results validate SNPs previously linked to reading and spelling in the general population in dyslexics and provide insights into their putative molecular pathomechanisms. PMID:27312598

  7. Polymorphisms in thymidylate synthase gene and susceptibility to breast cancer in a Chinese population: a case-control analysis

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    Liu Jiyong

    2006-05-01

    Full Text Available Abstract Background Accumulative evidence suggests that low folate intake is associated with increased risk of breast cancer. Polymorphisms in genes involved in folate metabolism may influence DNA methylation, nucleotide synthesis, and thus individual susceptibility to cancer. Thymidylate synthase (TYMS is a key enzyme that participates in folate metabolism and catalyzes the conversion of dUMP to dTMP in the process of DNA synthesis. Two potentially functional polymorphisms [a 28-bp tandem repeat in the TYMS 5'-untranslated enhanced region (TSER and a 6-bp deletion/insertion in the TYMS 3'-untranslated region (TS 3'-UTR] were suggested to be correlated with alteration of thymidylate synthase expression and associated with cancer risk. Methods To test the hypothesis that polymorphisms of the TYMS gene are associated with risk of breast cancer, we genotyped these two polymorphisms in a case-control study of 432 incident cases with invasive breast cancer and 473 cancer-free controls in a Chinese population. Results We found that the distribution of TS3'-UTR (1494del6 genotype frequencies were significantly different between the cases and controls (P = 0.026. Compared with the TS3'-UTR del6/del6 wild-type genotype, a significantly reduced risk was associated with the ins6/ins6 homozygous variant genotype (adjusted OR = 0.58, 95% CI = 0.35–0.97 but not the del6/ins6 genotype (OR = 1.09, 95% CI = 0.82–1.46. Furthermore, breast cancer risks associated with the TS3'-UTR del6/del6 genotype were more evident in older women, postmenopausal subjects, individuals with a younger age at first-live birth and individuals with an older age at menarche. However, there was no evidence for an association between the TSER polymorphism and breast cancer risks. Conclusion These findings suggest that the TS3'-UTR del6 polymorphism may play a role in the etiology of breast cancer. Further larger population-based studies as well as functional evaluation of the

  8. Risk factors for human salmonellosis originating from pigs, cattle, broiler chickens and egg laying hens: a combined case-control and source attribution analysis.

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    Lapo Mughini-Gras

    Full Text Available Several case-control studies have investigated risk factors for human salmonellosis while others have used Salmonella subtyping to attribute human infections to different food and animal reservoirs. This study combined case-control and source attribution data into a single analysis to explore risk factors at the point of exposure for human salmonellosis originating from four putative food-producing animal reservoirs (pigs, cattle, broilers and layers/eggs in the Netherlands. We confirmed that most human cases (∼ 90% were attributable to layers/eggs and pigs. Layers/eggs and broilers were the most likely reservoirs of salmonellosis in adults, in urban areas, and in spring/summer, whereas pigs and cattle were the most likely reservoirs of salmonellosis in children, in rural areas, and in autumn/winter. Several reservoir-specific risk factors were identified. Not using a chopping board for raw meat only and consuming raw/undercooked meat were risk factors for infection with salmonellas originating from pigs, cattle and broilers. Consuming raw/undercooked eggs and by-products were risk factors for layer/egg-associated salmonellosis. Using antibiotics was a risk factor for pig- and cattle-associated salmonellosis and using proton-pump inhibitors for salmonellosis attributable to any reservoir. Pig- and cattle-associated infections were also linked to direct contact with animals and environmental exposure (e.g. playing in sandboxes. Eating fish, meat in pastry, and several non-meat foods (fruit, vegetables and pasteurized dairy products were protective factors. Consuming pork and occupational exposure to animals and/or raw meats were protective against layer/egg-associated salmonellosis. We concluded that individuals acquiring salmonellosis from different reservoirs have different associated risk factors, suggesting that salmonellas may infect humans through various transmission pathways depending on their original reservoirs. The outcome of

  9. Risk factors for human salmonellosis originating from pigs, cattle, broiler chickens and egg laying hens: a combined case-control and source attribution analysis.

    Science.gov (United States)

    Mughini-Gras, Lapo; Enserink, Remko; Friesema, Ingrid; Heck, Max; van Duynhoven, Yvonne; van Pelt, Wilfrid

    2014-01-01

    Several case-control studies have investigated risk factors for human salmonellosis while others have used Salmonella subtyping to attribute human infections to different food and animal reservoirs. This study combined case-control and source attribution data into a single analysis to explore risk factors at the point of exposure for human salmonellosis originating from four putative food-producing animal reservoirs (pigs, cattle, broilers and layers/eggs) in the Netherlands. We confirmed that most human cases (∼ 90%) were attributable to layers/eggs and pigs. Layers/eggs and broilers were the most likely reservoirs of salmonellosis in adults, in urban areas, and in spring/summer, whereas pigs and cattle were the most likely reservoirs of salmonellosis in children, in rural areas, and in autumn/winter. Several reservoir-specific risk factors were identified. Not using a chopping board for raw meat only and consuming raw/undercooked meat were risk factors for infection with salmonellas originating from pigs, cattle and broilers. Consuming raw/undercooked eggs and by-products were risk factors for layer/egg-associated salmonellosis. Using antibiotics was a risk factor for pig- and cattle-associated salmonellosis and using proton-pump inhibitors for salmonellosis attributable to any reservoir. Pig- and cattle-associated infections were also linked to direct contact with animals and environmental exposure (e.g. playing in sandboxes). Eating fish, meat in pastry, and several non-meat foods (fruit, vegetables and pasteurized dairy products) were protective factors. Consuming pork and occupational exposure to animals and/or raw meats were protective against layer/egg-associated salmonellosis. We concluded that individuals acquiring salmonellosis from different reservoirs have different associated risk factors, suggesting that salmonellas may infect humans through various transmission pathways depending on their original reservoirs. The outcome of classical case-control

  10. Spatial analysis of lung, colorectal, and breast cancer on Cape Cod: An application of generalized additive models to case-control data

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    Aschengrau Ann

    2005-06-01

    Full Text Available Abstract Background The availability of geographic information from cancer and birth defect registries has increased public demands for investigation of perceived disease clusters. Many neighborhood-level cluster investigations are methodologically problematic, while maps made from registry data often ignore latency and many known risk factors. Population-based case-control and cohort studies provide a stronger foundation for spatial epidemiology because potential confounders and disease latency can be addressed. Methods We investigated the association between residence and colorectal, lung, and breast cancer on upper Cape Cod, Massachusetts (USA using extensive data on covariates and residential history from two case-control studies for 1983–1993. We generated maps using generalized additive models, smoothing on longitude and latitude while adjusting for covariates. The resulting continuous surface estimates disease rates relative to the whole study area. We used permutation tests to examine the overall importance of location in the model and identify areas of increased and decreased risk. Results Maps of colorectal cancer were relatively flat. Assuming 15 years of latency, lung cancer was significantly elevated just northeast of the Massachusetts Military Reservation, although the result did not hold when we restricted to residences of longest duration. Earlier non-spatial epidemiology had found a weak association between lung cancer and proximity to gun and mortar positions on the reservation. Breast cancer hot spots tended to increase in magnitude as we increased latency and adjusted for covariates, indicating that confounders were partly hiding these areas. Significant breast cancer hot spots were located near known groundwater plumes and the Massachusetts Military Reservation. Discussion Spatial epidemiology of population-based case-control studies addresses many methodological criticisms of cluster studies and generates new exposure

  11. The role of TLR2, TLR4 and CD14 genetic polymorphisms in gastric carcinogenesis: a case-control study and meta-analysis.

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    Natalia Castaño-Rodríguez

    Full Text Available BACKGROUND: In addition to Helicobacter pylori infection, host genetic factors contribute to gastric cancer (GC. Recognition of H. pylori is known to involve Toll-like receptors (TLR, which subsequently leads to activation of NF-κB. Thus, the overall aim of this study was to estimate for the first time the pooled effect size of polymorphisms in TLR2, TLR4 and CD14 on GC development through a meta-analysis. METHODS: A case-control study comprising 284 ethnic Chinese individuals (70 non-cardia GC cases and 214 functional dyspepsia controls was conducted for the genotyping of TLR2 -196 to -174del, CD14 -260 C/T and TLR4 rs11536889 using PCR, RT-PCR and mass spectrometry. Case-control studies of TLR2, TLR4 and CD14 polymorphisms and GC were searched up to June 2012. Pooled odds ratios and 95% confidence intervals were obtained by means of the random effects model. RESULTS: In our ethnic Chinese case-control study, the TLR4 rs11536889 C allele increased the risk of GC (OR: 1.89, 95%CI: 1.23-2.92 while the CD14 -260 T allele was protective (OR: 0.62, 95%CI: 0.42-0.91. TLR2 -196 to -174 increased the risk of GC only in H. pylori-infected individuals (OR: 3.10, 95%CI: 1.27-7.60. In the meta-analysis, TLR4 Asp299Gly showed borderline results in the general analysis (pooled OR: 1.58, 95%CI: 0.98-2.60, nevertheless, stratified analysis by ethnicity showed that the mutant allele was a definitive risk factor for GC in Western populations (pooled OR: 1.87, 95%CI: 1.31-2.65. There was a potential association between the TLR2 -196 to -174 deletion allele and GC in Japanese (pooled OR: 1.18, 95%CI: 0.96-1.45. TLR4 Thr399Ile did not provide significant results. CONCLUSIONS: TLR4 rs11536889 and CD14 -260 C/T are associated with non-cardia GC in Chinese. Based on our meta-analysis, the TLR signalling pathway is involved in gastric carcinogenesis, TLR4 Asp299Gly and TLR2 -196 to -174del showing associations with GC in an ethnic-specific manner.

  12. Genetic variation in IL6 gene and type 2 diabetes: tagging-SNP haplotype analysis in large-scale case-control study and meta-analysis.

    Science.gov (United States)

    Qi, Lu; van Dam, Rob M; Meigs, James B; Manson, JoAnn E; Hunter, David; Hu, Frank B

    2006-06-01

    Interleukin-6 (IL-6, gene symbol IL6) is a proinflammatory cytokine. High circulating IL-6 levels have been associated with insulin resistance and greater risk of type 2 diabetes. Using a linkage disequilibrium (LD)-based approach, we sought to investigate the associations of the common polymorphisms comprehensively defining the genetic variability at the IL6 locus with diabetes risk. We conducted a case-control study of 2691 cases of type 2 diabetes (1692 women and 999 men) and 3237 control subjects (2238 women and 999 men) from the Nurses' Health Study and the Health Professional Follow-up Study. Pairwise LD analysis indicated that all the IL6 polymorphisms (rs2069827, rs1800797, rs1800795, rs1554606, rs2069849, rs2069861 and rs1818879) were in strong LD. We did not find significant associations between IL6 polymorphisms and the risk of type 2 diabetes in women or men, individually or in haplotypes. In addition, none of the IL6 polymorphisms was significantly associated with the plasma levels of IL-6 in the control subjects. Our meta-analysis of 5383 diabetes case and 12 069 controls indicated a null association between the best-studied 5' promoter polymorphism--174G>C (rs1800795)--and diabetes risk. Diversity in adiposity, age and sex could not account for the heterogeneity across different studies. In summary, the data in this study do not support substantial associations between the common polymorphisms in IL6 gene and circulating IL-6 levels and the risk of type 2 diabetes.

  13. Olive oil consumption and risk of CHD and/or stroke: a meta-analysis of case-control, cohort and intervention studies.

    Science.gov (United States)

    Martínez-González, Miguel A; Dominguez, Ligia J; Delgado-Rodríguez, Miguel

    2014-07-28

    Increasing evidence suggests that the Mediterranean diet can reduce the risk of CVD. Olive oil is the hallmark of this dietary pattern. We conducted a meta-analysis of case-control, prospective cohort studies and a randomised controlled trial investigating the specific association between olive oil consumption and the risk of CHD (101,460 participants) or stroke (38,673 participants). The results of all observational studies were adjusted for total energy intake. The random-effects model assessing CHD as an outcome showed a relative risk (RR) of 0.73 (95% CI 0.44, 1.21) in case-control studies and 0.96 (95% CI 0.78, 1.18) in cohort studies for a 25 g increase in olive oil consumption. In cohort studies, the random-effects model assessing stroke showed a RR of 0.74 (95% CI 0.60, 0.92). The random-effects model combining all cardiovascular events (CHD and stroke) showed a RR of 0.82 (95% CI 0.70, 0.96). Evidence of heterogeneity was apparent for CHD, but not for stroke. Both the Egger test (P= 0.06) and the funnel plot suggested small-study effects. Available studies support an inverse association of olive oil consumption with stroke (and with stroke and CHD combined), but no significant association with CHD. This finding is in agreement with the recent successful results of the PREDIMED randomised controlled trial.

  14. A Prospective Nested Case Control Study on the RisK Factors of Cryptococcus Neoformans Meningitis%新型隐球菌性脑膜炎发病相关危险因素的前瞻性巢式病例对照研究

    Institute of Scientific and Technical Information of China (English)

    江顺福; 曹铭华; 曹玮; 吴明超; 朱殊

    2014-01-01

    ,we had chosen citizens from 2 villages in the 2 countries and 1 district according to certain proportion and finally 8 348 citizens were brought into our research. The cohort was followed for two years from July,2O11 to July,2O13. We used the 1:1 matching prospective nested case-control study method to explore the relatedfactorsofcryptococcusneoformansmeningitisandLogisticregressionmodeltodeterminetheriskfactors.Results Until July,2O13,63 cases of cryptococcus neoformans meningitis were found in the follow-up cohort including 38 males and 25 fe-males,aged 5~64 with a median age of 39. 5(case group). According to matching principle,another 63 citizen without the case were selected including 38 males and 25 females,aged 4~67 with a median age of 38. 7(control group). Single factor a-nalysis of the 1:1 matching material indicated that educational background,single,unemployed,dove bird feces,diabetes mel-litus,AIDS,contacting with dead animals factors were into the regression equation(Panalysis showed that single(OR=1. 3O8),unemployed(OR=1. O32),diabetes mellitus(OR=2. O5O),diabetes mel-litus,AIDS(OR=3. 87O),contacted the dove bird feces(OR=3. O82),contacting with dead animals(OR=2. 812)were the risk factors of cryptococcus neoformans meningitis and educational background was the protective factor(OR=O. 9O8). Con-clusion Single,unemployed,diabetesmellitus,AIDS,onceexposedtothedovebirdfecesandrotofbiomassaretheriskfac-tors related to cryptococcal meningitis. The research findings provide further evidence for the etiology of cryptococcal meningitis.

  15. Analysis of the wood duck nesting box program on Wapanocca National Wildlife Refuge: 1977 - 1986

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The wood duck nesting box program on Wapanocca National Wildlife Refuge has undergone transition and expansion throughout the years. These changes have occurred as...

  16. Louisiana ESI: NESTS (Nest Points)

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    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for seabird and wading bird nesting colonies in coastal Louisiana. Vector points in this data set represent...

  17. Hawaii ESI: NESTS (Nest Points)

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    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for seabird nesting colonies in coastal Hawaii. Vector points in this data set represent locations of...

  18. Epstein-Barr Virus-Positive Diffuse Large B-Cell Lymphoma in the Elderly: A Matched Case-Control Analysis.

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    Chen-Ge Song

    Full Text Available Epstein-Barr virus (EBV-positive diffuse large B-cell lymphoma (DLBCL in the elderly has rarely been reported. This study aimed to explore the clinical characteristics and prognosis of this entity.In situ hybridization (ISH analysis of Epstein-Barr virus (EBV and immunohistochemistry was performed in 230 tumor specimens from consecutive de novo DLBCL patients over 50 years old. A matched-case control analysis (1:3 was utilized to compare EBV-positive and EBV-negative DLBCL in the elderly.A total of 16 patients (7.0% were diagnosed with EBV-positive DLBCL. Of these 16 cases, the median age was 62 years, with a male to female ratio of 11:5. Elderly EBV-positive DLBCL patients had a higher incidence of non-germinal center B-cell (non-GCB subtypes (87.5% and high Ki67 (75% and CD30 expression (93.8%. For EBV-positive patients undergoing initial chemotherapy, 7 of 16 (43.8% had complete remission, 2 (12.5% had partial remission, 2 (12.5% had stable disease, and 5 (31.3% had progressive disease. The median overall survival was 9 months for the EBV-positive patients. A matched-case control analysis suggested that EBV-positive patients had inferior survival outcomes compared with EBV-negative patients (3-year progression-free survival [PFS]: 25% vs. 76.7%, respectively; 3-year overall survival [OS]: 25% vs. 77.4%, respectively; P<0.001.EBV-positive DLBCL of the elderly is associated with an inferior clinical course and inferior survival outcomes. The role of EBV in this disease and the optimal management of this subgroup warrants further investigation.

  19. Diet of yellow-billed loons (Gavia adamsii) in Arctic lakes during the nesting season inferred from fatty acid analysis

    Science.gov (United States)

    Haynes, T B; Schmutz, Joel A.; Bromaghin, Jeffrey; Iverson, S J; Padula, V. M.; Rosenberger, A E

    2015-01-01

    Understanding the dietary habits of yellow-billed loons (Gavia adamsii) can give important insights into their ecology, however, studying the diet of loons is difficult when direct observation or specimen collection is impractical. We investigate the diet of yellow-billed loons nesting on the Arctic Coastal Plain of Alaska using quantitative fatty acid signature analysis. Tissue analysis from 26 yellow-billed loons and eleven prey groups (nine fish species and two invertebrate groups) from Arctic lakes suggests that yellow-billed loons are eating high proportions of Alaska blackfish (Dallia pectoralis), broad whitefish (Coregonus nasus) and three-spined stickleback (Gasterosteus aculeatus) during late spring and early summer. The prominence of blackfish in diets highlights the widespread availability of blackfish during the early stages of loon nesting, soon after spring thaw. The high proportions of broad whitefish and three-spined stickleback may reflect a residual signal from the coastal staging period prior to establishing nesting territories on lakes, when loons are more likely to encounter these species. Our analyses were sensitive to the choice of calibration coefficient based on data from three different species, indicating the need for development of loon-specific coefficients for future study and confirmation of our results. Regardless, fish that are coastally distributed and that successfully overwinter in lakes are likely key food items for yellow-billed loons early in the nesting season.

  20. MUC1 Predicts Colorectal Cancer Metastasis: A Systematic Review and Meta-Analysis of Case Controlled Studies.

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    Yunhui Zeng

    Full Text Available To evaluate the predicting value of MUC1 expression in lymph node and distant metastasis of colorectal cancer (CRC.Pubmed/ MEDLINE and EMBASE were searched to identify eligible studies that evaluated the correlation between MUC1 and CRC. A meta-analysis was conducted to evaluate the impact of MUC1 expression on CRC metastasis.A total of 18 studies (n = 3271 met inclusion criteria and the mean Newcastle-Ottawa Scale (NOS score was 6.3 with a range from 4 to 8. The pooled OR in the meta-analysis of 15 studies indicated that positive MUC1 expression correlated with more CRC node metastasis (OR = 2.32, 95% CI = 1.63-3.29. The data synthesis of 6 studies suggested that MUC1 expression predicted more possibility of CRC distant metastasis (OR = 2.22, 95% CI = 1.23-4.00. In addition, the combined OR of 7 studies showed that MUC1 expression indicated higher Duke's stage (OR = 3.02, 95% CI = 2.11-4.33. No publication bias was found in the mate-analysis by Begg's test or Egger's test with the exception of the meta-analysis of MUC1 with CRC node metastasis (Begg's test p = 0.729, Egger's test p = 0.000.Despite of some modest bias, the pooled evidence suggested that MUC1 expression was significantly correlated with CRC metastasis.

  1. Anxiety in Adolescents Born Preterm or with Very Low Birthweight: A Meta-Analysis of Case-Control Studies

    Science.gov (United States)

    Somhovd, Mikael J.; Hansen, Bo M.; Brok, Jesper; Esbjorn, Barbara H.; Greisen, Gorm

    2012-01-01

    Aim: To determine if adolescents who are born very preterm (less than 32wks; of gestation) and/or with very low birthweight (VLBW; less than 1500g) have a higher risk of experiencing clinically significant anxiety problems. Method: We used a systematic review and meta-analysis. We searched the databases ISI Web of Knowledge, PubMed, PsycNET,…

  2. FTO Genotype and Type 2 Diabetes Mellitus: Spatial Analysis and Meta-Analysis of 62 Case-Control Studies from Different Regions

    Science.gov (United States)

    Yang, Ying; Liu, Boyang; Xia, Wei; Yan, Jing; Liu, Huan-Yu; Hu, Ling; Liu, Song-Mei

    2017-01-01

    Type 2 diabetes mellitus (T2DM) is a global health problem that results from the interaction of environmental factors with genetic variants. Although a number of studies have suggested that genetic polymorphisms in the fat mass and obesity-associated (FTO) gene are associated with T2DM risk, the results have been inconsistent. To investigate whether FTO polymorphisms associate with T2DM risk and whether this association is region-related, we performed this spatial analysis and meta-analysis. More than 60,000 T2DM patients and 90,000 controls from 62 case-control studies were included in this study. Odds ratios (ORs), 95% confidence intervals (CIs) and Moran’s I statistic were used to estimate the association between FTO rs9939609, rs8050136, rs1421085, and rs17817499, and T2DM risk in different regions. rs9939609 (OR = 1.15, 95% CI 1.11–1.19) and rs8050136 (OR = 1.14, 95% CI 1.10–1.18) conferred a predisposition to T2DM. After adjustment for body mass index (BMI), the association remained statistically significant for rs9939609 (OR = 1.11, 95% CI 1.05–1.17) and rs8050136 (OR = 1.08, 95% CI 1.03–1.12). In the subgroup analysis of rs9939609 and rs8050136, similar results were observed in East Asia, while no association was found in North America. In South Asia, an association for rs9939609 was revealed but not for rs8050136. In addition, no relationship was found with rs1421085 or rs17817499 regardless of adjustment for BMI. Moran’s I statistic showed that significant positive spatial autocorrelations existed in rs9939609 and rs8050136. Studies on rs9939609 and rs8050136 focused on East Asia and South Asia, whereas studies on rs1421085 and rs17817499 were distributed in North America and North Africa. Our data suggest that the associations between FTO rs9939609, rs8050136 and T2DM are region-related, and the two single-nucleotide polymorphisms contribute to an increased risk of T2DM. Future studies should investigate this issue in more regions. PMID

  3. FTO Genotype and Type 2 Diabetes Mellitus: Spatial Analysis and Meta-Analysis of 62 Case-Control Studies from Different Regions

    Directory of Open Access Journals (Sweden)

    Ying Yang

    2017-02-01

    Full Text Available Type 2 diabetes mellitus (T2DM is a global health problem that results from the interaction of environmental factors with genetic variants. Although a number of studies have suggested that genetic polymorphisms in the fat mass and obesity-associated (FTO gene are associated with T2DM risk, the results have been inconsistent. To investigate whether FTO polymorphisms associate with T2DM risk and whether this association is region-related, we performed this spatial analysis and meta-analysis. More than 60,000 T2DM patients and 90,000 controls from 62 case-control studies were included in this study. Odds ratios (ORs, 95% confidence intervals (CIs and Moran’s I statistic were used to estimate the association between FTO rs9939609, rs8050136, rs1421085, and rs17817499, and T2DM risk in different regions. rs9939609 (OR = 1.15, 95% CI 1.11–1.19 and rs8050136 (OR = 1.14, 95% CI 1.10–1.18 conferred a predisposition to T2DM. After adjustment for body mass index (BMI, the association remained statistically significant for rs9939609 (OR = 1.11, 95% CI 1.05–1.17 and rs8050136 (OR = 1.08, 95% CI 1.03–1.12. In the subgroup analysis of rs9939609 and rs8050136, similar results were observed in East Asia, while no association was found in North America. In South Asia, an association for rs9939609 was revealed but not for rs8050136. In addition, no relationship was found with rs1421085 or rs17817499 regardless of adjustment for BMI. Moran’s I statistic showed that significant positive spatial autocorrelations existed in rs9939609 and rs8050136. Studies on rs9939609 and rs8050136 focused on East Asia and South Asia, whereas studies on rs1421085 and rs17817499 were distributed in North America and North Africa. Our data suggest that the associations between FTO rs9939609, rs8050136 and T2DM are region-related, and the two single-nucleotide polymorphisms contribute to an increased risk of T2DM. Future studies should investigate this issue in more regions.

  4. Association of the 5HTR2A gene with suicidal behavior: CASE-control study and updated meta-analysis

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    González-Castro Thelma Beatriz

    2013-01-01

    Full Text Available Abstract Background The polymorphism rs6313 (T102C has been associated with suicidal behavior in case–control and meta-analysis studies, but results and conclusions remain controversial. The aim of the present study was to examine the association between T102C with suicidal behavior in a case–control study and, to assess the combined evidence – this case–control study and available data from other related studies – we carried out a meta-analysis. Methods We conducted a case–control study that included 161 patients with suicide attempts and 244 controls; we then performed a meta-analysis. The following models were evaluated in the meta-analysis: A C allele vs T allele; B T allele vs C allele; C Caucasian population, D Asian population, and E suicide attempters with schizophrenia. Results We found an association between attempted suicide and control participants for genotype (χ2=6.28, p=0.04, df=2 and allele (χ2=6.17, p=0.01, df=1, OR 1.48 95% IC: 1.08-2.03 frequencies in the case–control study. The meta-analysis, comprising 23 association studies (including the present one, showed that the rs6313 polymorphism is not associated with suicidal behavior for the following comparisons:T allele vs C allele (OR: 1.03; 95% CI 0.93-1.13; p(Z=0.44; C allele vs T allele: (OR:0.99; 95% CI: 0.90-1.08; p(Z=0.22; Caucasians (OR:1.09; 95% CI: 0.96-1.23, and Asians (OR:0.96; 95% CI: 0.84-1.09. Conclusion Our results showed association between the rs6313 (T102C polymorphism and suicidal behavior in the case–control study. However, the meta-analysis showed no evidence of association. Therefore, more studies are necessary to determine conclusively an association between T102C and suicidal behavior.

  5. The associations between VEGF gene polymorphisms and diabetic retinopathy susceptibility: a meta-analysis of 11 case-control studies.

    Science.gov (United States)

    Han, Liyuan; Zhang, Lina; Xing, Wenhua; Zhuo, Renjie; Lin, XiaLu; Hao, Yanhua; Wu, Qunhong; Zhao, Jinshun

    2014-01-01

    AIMS. Published data on the associations of VEGF polymorphisms with diabetic retinopathy (DR) susceptibility are inconclusive. A systematic meta-analysis was undertaken to clarify this topic. METHODS. Data were collected from the following electronic databases: PubMed, Embase, OVID, Web of Science, Elsevier Science Direct, Excerpta Medica Database (EMBASE), and Cochrane Library with the last report up to January 10, 2014. ORs and 95% CIs were calculated for VEGF-2578C/A (rs699947), -1154G/A (rs1570360), -460T/C (rs833061), -634G>C (rs2010963), and +936C/T (rs3025039) in at least two published studies. Meta-analysis was performed in a fixed/random effect model by using the software STATA 12.0. RESULTS. A total of 11 studies fulfilling the inclusion criteria were included in this meta-analysis. A significant relationship between VEGF+936C/T (rs3025039) polymorphism and DR was found in a recessive model (OR = 3.19, 95% CI = 1.20-8.41, and P(z) = 0.01) in Asian and overall populations, while a significant association was also found between -460T/C (rs833061) polymorphism and DR risk under a recessive model (OR = 2.12, 95% CI = 1.12-4.01, and P(z) = 0.02). CONCLUSIONS. Our meta-analysis demonstrates that +936C/T (rs3025039) is likely to be associated with susceptibility to DR in Asian populations, and the recessive model of -460T/C (rs833061) is associated with elevated DR susceptibility.

  6. The Associations between VEGF Gene Polymorphisms and Diabetic Retinopathy Susceptibility: A Meta-Analysis of 11 Case-Control Studies

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    Liyuan Han

    2014-01-01

    Full Text Available Aims. Published data on the associations of VEGF polymorphisms with diabetic retinopathy (DR susceptibility are inconclusive. A systematic meta-analysis was undertaken to clarify this topic. Methods. Data were collected from the following electronic databases: PubMed, Embase, OVID, Web of Science, Elsevier Science Direct, Excerpta Medica Database (EMBASE, and Cochrane Library with the last report up to January 10, 2014. ORs and 95% CIs were calculated for VEGF–2578C/A (rs699947, –1154G/A (rs1570360, –460T/C (rs833061, −634G>C (rs2010963, and +936C/T (rs3025039 in at least two published studies. Meta-analysis was performed in a fixed/random effect model by using the software STATA 12.0. Results. A total of 11 studies fulfilling the inclusion criteria were included in this meta-analysis. A significant relationship between VEGF+936C/T (rs3025039 polymorphism and DR was found in a recessive model (OR = 3.19, 95% CI = 1.20–8.41, and P(z=0.01 in Asian and overall populations, while a significant association was also found between –460T/C (rs833061 polymorphism and DR risk under a recessive model (OR = 2.12, 95% CI = 1.12–4.01, and P(z=0.02. Conclusions. Our meta-analysis demonstrates that +936C/T (rs3025039 is likely to be associated with susceptibility to DR in Asian populations, and the recessive model of –460T/C (rs833061 is associated with elevated DR susceptibility.

  7. The rs2237892 Polymorphism in KCNQ1 Influences Gestational Diabetes Mellitus and Glucose Levels: A Case-Control Study and Meta-Analysis.

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    Deng Ao

    Full Text Available Recent genetic studies have shown that potassium voltage-gated channel, KQT-like subfamily, member1 (KCNQ1 gene is related to gestational diabetes mellitus (GDM. However, studies for the rs2237892 polymorphism in KCNQ1 and GDM remain conflicting in Asians. Furthermore, associations of this polymorphism with glucose levels during oral glucose tolerance test (OGTT have not been described in Chinese pregnant women. The present study aimed to provide evidence for the associations of rs2237892 in KCNQ1 with GDM and glucose levels, and to systematically evaluate the effect of rs2237892 on GDM in Asians.A case-control study on 562 women with GDM and 453 controls was conducted in Beijing, China. The association of rs2237892 with risk of GDM was analyzed using logistic regression. The associations with quantitative glucose levels were assessed using linear regression models. A meta-analysis including the present case-control study and four previously published reports in Asians was conducted.The rs2237892 polymorphism in KCNQ1 was associated with GDM (OR (95%CI =1.99(1.26-3.15. Additionally, the polymorphism was associated with levels of 1h and 2h glucose during OGTT. The pre-pregnancy BMI, age and genotypes of KCNQ1 polymorphism were independent risk factors of GDM. Subsequently, we performed a meta-analysis in Asians. In total, C-allele carriers of rs2237892 polymorphism had a 50% higher risk for GDM (OR (95%CI =1.50(1.15-1.78.The study demonstrated for the first time that the KCNQ1 rs2237892 polymorphism was associated with GDM and glucose levels in Chinese women. The study provides systematic evidence for the association between this polymorphism and GDM in Asians.

  8. A case-control study of maternal periconceptual and pregnancy recreational drug use and fetal malformation using hair analysis.

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    Anna L David

    Full Text Available OBJECTIVE: Maternal recreational drug use may be associated with the development of fetal malformations such as gastroschisis, brain and limb defects, the aetiology due to vascular disruption during organogenesis. Using forensic hair analysis we reported evidence of recreational drug use in 18% of women with a fetal gastroschisis. Here we investigate this association in a variety of fetal malformations using the same method. METHODS: In a multi-centre study, women with normal pregnancies (controls and those with fetal abnormalities (cases gave informed consent for hair analysis for recreational drug metabolites using mass spectrometry. Hair samples cut at the root were tested in sections corresponding to 3 month time periods (pre and periconceptual period. RESULTS: Women whose fetus had gastroschisis, compared to women with a normal control fetus, were younger (mean age 23.78 ± SD4.79 years, 18-37 vs 29.79 ± SD6 years, 18-42, p = 0.00001, were more likely to have evidence of recreational drug use (15, 25.4% vs 21, 13%, OR2.27, 95thCI 1.08-4.78, p = 0.028, and were less likely to report periconceptual folic acid use (31, 53.4% vs 124, 77.5%, OR0.33, 95thCI 0.18-0.63, p = 0.001. Age-matched normal control women were no less likely to test positive for recreational drugs than women whose fetus had gastroschisis. After accounting for all significant factors, only young maternal age remained significantly associated with gastroschisis. Women with a fetus affected by a non-neural tube central nervous system (CNS anomaly were more likely to test positive for recreational drugs when compared to women whose fetus was normal (7, 35% vs 21, 13%, OR3.59, 95th CI1.20-10.02, p = 0.01. CONCLUSIONS: We demonstrate a significant association between non neural tube CNS anomalies and recreational drug use in the periconceptual period, first or second trimesters, but we cannot confirm this association with gastroschisis. We confirm the association of

  9. Genetic polymorphism in HLA-G 3'UTR 14-bp ins/del and risk of cancer: a meta-analysis of case-control study.

    Science.gov (United States)

    Li, Tao; Huang, Haohai; Liao, Dan; Ling, Huahuang; Su, Bingguang; Cai, Maode

    2015-08-01

    Accumulating evidence has suggested that the human leucocyte antigen-G (HLA-G) 14 bp ins/del polymorphism might be related to cancer susceptibility. However, epidemiologic findings have been inconsistent. Therefore, we performed a meta-analysis of case-control study to derive a more precise estimation of this association. Electronic databases were searched to identify all eligible studies of HLA-G 14 bp ins/del polymorphism and cancer risk. Odds ratios (ORs) with 95 % confidence intervals (CIs) were calculated to evaluate the strength of the association in fixed-effects model or random-effects model according to heterogeneity. Publication bias, sensitivity analysis and subgroup analyses based on cancer type, ethnicity, source of controls and sample size were also performed. A total of 14 case-control studies, involving 2,757 cases and 3,972 controls, were included in the present meta-analysis. The pooled analysis showed that there is no significant relationship between the HLA-G 14 bp ins/del polymorphism and cancer susceptibility under the genetic models (for the allele model del vs. ins: OR 1.13, 95 % CI 1.00-1.27; for the homozygote comparison model del/del vs. ins/ins: OR 1.22, 95 % CI 0.95-1.56; for the dominant model del/del + ins/del vs. ins/ins: OR 1.15, 95 % CI 0.94-1.42; for recessive model del/del vs. ins/del + ins/ins: OR 1.13, 95 % CI 0.96-1.34; respectively). Subgroup analyses indicated significant association among breast cancer, population based control and the large sample size group in some genetic models. Our investigations demonstrate that genotypes for the HLA-G 14 bp ins/del polymorphism may be not associated with overall cancer risk. In a subgroup meta-analysis, however, HLA-G 14-bp ins/del polymorphism might contribute to breast cancer susceptibility.

  10. Tricyclic antidepressant use and risk of fractures: a meta-analysis of cohort and case-control studies.

    Science.gov (United States)

    Wu, Qing; Qu, Wenchun; Crowell, Michael D; Hentz, Joseph G; Frey, Keith A

    2013-04-01

    Because studies of the association between tricyclic antidepressant (TCA) treatment and risk of fracture have shown inconsistent findings, we sought to assess whether people who take TCAs are at increased risk of fracture. Relevant studies published by June 2012 were identified through database searches of Scopus, MEDLINE, EMBASE, PsycINFO, ISI Web of Science, and WorldCat Dissertations and Theses from their inception, and manual searching of reference lists. Only original studies that examined the association between TCA treatment and risk of fracture were included. Two investigators independently conducted literature searches, study selection, study appraisal, and data abstraction using a standardized protocol. Disagreements were resolved by consensus. Twelve studies met inclusion criteria. Because of the heterogeneity of these studies, random-effects models were used to pool estimates of effect. Overall, TCA use was associated with significantly increased fracture risk (relative risk [RR], 1.45; 95% confidence interval [CI], 1.31-1.60; p < 0.001). Increased fracture risk associated with TCA use was also observed in studies that adjusted for bone mineral density (RR, 1.54; 95% CI, 1.24-1.90; p < 0.001) or depression (RR, 1.49; 95% CI, 1.28-1.67; p < 0.001). Strength of association with TCA exposure duration ≥6 weeks (RR, 1.13; 95% CI, 1.00-1.28) was substantially weaker than association with TCA exposure duration <6 weeks (RR, 2.40; 95% CI, 1.41-4.08). Prior TCA exposure had no significant effect on fracture risk (RR, 1.04; 95% CI, 0.86-1.26; p = 0.70). After accounting for publication bias, we found the overall association between TCA use and fracture risk to be slightly weaker (RR, 1.36; 95% CI, 1.24-1.50) but still significant (p < 0.001). Findings of this meta-analysis indicate that treatment with TCAs may convey an increased risk of fracture, independent of depression and bone mineral density.

  11. Association of GSTP1 Ile105Val polymorphism and risk of head and neck cancers: a meta-analysis of 28 case-control studies.

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    Juntian Lang

    Full Text Available BACKGROUND AND AIMS: The Glutathione S-transferase P1 (GSTP1 polymorphism have been considered a risk modifier for developing head and neck cancer (HNC in many studies; however, the results of such studies are inconsistent. The aim of this study was to evaluate the possible association between the GSTP1 Ile105Val polymorphism and risk of HNC. METHOD: We performed a search in the relevant electronic database and a meta-analysis based on 28 published case-control studies that included 6,404 cases and 6,523 controls. To take into account the possibility of heterogeneity across the studies, a Chi-square based I(2-statistic test was performed. Crude pooled odds ratios (ORs with 95% confidence intervals (CIs were assessed using both fixed-effects and random-effects models. RESULTS: The results of this meta-analysis showed that the GSTP1 Ile105Val polymorphism was not significantly associated with risk of HNC in the overall study population (pooled OR 1.00, 95% CI 0.92-1.09 or in subgroup analyses stratified by ethnicity, sample size, tumor site or publication year. Moreover, substantial evidence of heterogeneity among the studies was observed. Publication year was identified as the main cause of heterogeneity. CONCLUSION: This meta-analysis does not support a significant association between the GSTP1 Ile105Val polymorphism and risk of HNC.

  12. Associations of IL-23R polymorphisms with ankylosing spondylitis in East Asian population: a new case-control study and a meta-analysis.

    Science.gov (United States)

    Chen, C; Zhang, X; Li, J; Wang, Y

    2012-04-01

    Interleukin-23 receptor (IL-23R) 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. Here, we conducted a new case-control study investigating this relationship in Chinese Han population and then performed a meta-analysis in East Asian population. The Chinese Han study included 200 cases and 200 controls. 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, 1384 cases and 1710 controls from five different studies and the new Chinese Han study were combined using Review Manager software Version 5.1.1. Mantel-Haenszel test was used to calculate fixed effects pooled ORs. No association with AS was observed in the Chinese Han study. Meta-analysis showed that no SNP was significantly associated with AS in East Asian population. In conclusion, we found no evidence for association between IL-23R and AS in East Asian population. Major attention should be paid to other genes belonged to IL-23 signalling pathway network in the future.

  13. Multiple causation of phylogeographical pattern as revealed by nested clade analysis of the bamboo viper (Trimeresurus stejnegeri) within Taiwan.

    Science.gov (United States)

    Creer, S; Malhotra, A; Thorpe, R S; Chou, W H

    2001-08-01

    In order to assess the utility of nested clade analysis, both standard phylogenetic algorithms and nested clade analysis were performed on a geographically widespread survey of mitochondrial DNA haplotypes of the bamboo viper, Trimeresurus stejnegeri, within Taiwan. Gross tree topologies were congruent for all analyses and indicated the presence of two geographically overlapping clades within Taiwan. The smaller lineage was restricted to the north and east coasts, whereas the larger lineage occupied all but the northern range of the species within Taiwan including the Pacific offshore populations of Green and Orchid Islands. The phylogeographical pattern supports the existence of at least one colonization event from the continent since the initial isolation of Taiwan from the mainland in the Pliocene. However, determining the exact number of colonization events was not possible due to the simultaneous vicariant forces of hypothesized continental landbridge connections and the occurrence of dramatic in situ orogenesis throughout the Pleistocene. Nested clade analysis provided multiple temporal and spatial population historical inferences that are not possible with standard analyses and therefore should become widely applied to future phylogeographical studies.

  14. Relationship between Long Chain n-3 Polyunsaturated Fatty Acids and Autism Spectrum Disorder: Systematic Review and Meta-Analysis of Case-Control and Randomised Controlled Trials

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    Hajar Mazahery

    2017-02-01

    Full Text Available Omega-3 long chain polyunsaturated fatty acid supplementation (n-3 LCPUFA for treatment of Autism Spectrum Disorder (ASD is popular. The results of previous systematic reviews and meta-analyses of n-3 LCPUFA supplementation on ASD outcomes were inconclusive. Two meta-analyses were conducted; meta-analysis 1 compared blood levels of LCPUFA and their ratios arachidonic acid (ARA to docosahexaenoic acid (DHA, ARA to eicosapentaenoic acid (EPA, or total n-6 to total n-3 LCPUFA in ASD to those of typically developing individuals (with no neurodevelopmental disorders, and meta-analysis 2 compared the effects of n-3 LCPUFA supplementation to placebo on symptoms of ASD. Case-control studies and randomised controlled trials (RCTs were identified searching electronic databases up to May, 2016. Mean differences were pooled and analysed using inverse variance models. Heterogeneity was assessed using I2 statistic. Fifteen case-control studies (n = 1193 were reviewed. Compared with typically developed, ASD populations had lower DHA (−2.14 [95% CI −3.22 to −1.07]; p < 0.0001; I2 = 97%, EPA (−0.72 [95% CI −1.25 to −0.18]; p = 0.008; I2 = 88%, and ARA (−0.83 [95% CI, −1.48 to −0.17]; p = 0.01; I2 = 96% and higher total n-6 LCPUFA to n-3 LCPUFA ratio (0.42 [95% CI 0.06 to 0.78]; p = 0.02; I2 = 74%. Four RCTs were included in meta-analysis 2 (n = 107. Compared with placebo, n-3 LCPUFA improved social interaction (−1.96 [95% CI −3.5 to −0.34]; p = 0.02; I2 = 0 and repetitive and restricted interests and behaviours (−1.08 [95% CI −2.17 to −0.01]; p = 0.05; I2 = 0. Populations with ASD have lower n-3 LCPUFA status and n-3 LCPUFA supplementation can potentially improve some ASD symptoms. Further research with large sample size and adequate study duration is warranted to confirm the efficacy of n-3 LCPUFA.

  15. Relationship between Long Chain n-3 Polyunsaturated Fatty Acids and Autism Spectrum Disorder: Systematic Review and Meta-Analysis of Case-Control and Randomised Controlled Trials

    Science.gov (United States)

    Mazahery, Hajar; Stonehouse, Welma; Delshad, Maryam; Kruger, Marlena C.; Conlon, Cathryn A.; Beck, Kathryn L.; von Hurst, Pamela R.

    2017-01-01

    Omega-3 long chain polyunsaturated fatty acid supplementation (n-3 LCPUFA) for treatment of Autism Spectrum Disorder (ASD) is popular. The results of previous systematic reviews and meta-analyses of n-3 LCPUFA supplementation on ASD outcomes were inconclusive. Two meta-analyses were conducted; meta-analysis 1 compared blood levels of LCPUFA and their ratios arachidonic acid (ARA) to docosahexaenoic acid (DHA), ARA to eicosapentaenoic acid (EPA), or total n-6 to total n-3 LCPUFA in ASD to those of typically developing individuals (with no neurodevelopmental disorders), and meta-analysis 2 compared the effects of n-3 LCPUFA supplementation to placebo on symptoms of ASD. Case-control studies and randomised controlled trials (RCTs) were identified searching electronic databases up to May, 2016. Mean differences were pooled and analysed using inverse variance models. Heterogeneity was assessed using I2 statistic. Fifteen case-control studies (n = 1193) were reviewed. Compared with typically developed, ASD populations had lower DHA (−2.14 [95% CI −3.22 to −1.07]; p < 0.0001; I2 = 97%), EPA (−0.72 [95% CI −1.25 to −0.18]; p = 0.008; I2 = 88%), and ARA (−0.83 [95% CI, −1.48 to −0.17]; p = 0.01; I2 = 96%) and higher total n-6 LCPUFA to n-3 LCPUFA ratio (0.42 [95% CI 0.06 to 0.78]; p = 0.02; I2 = 74%). Four RCTs were included in meta-analysis 2 (n = 107). Compared with placebo, n-3 LCPUFA improved social interaction (−1.96 [95% CI −3.5 to −0.34]; p = 0.02; I2 = 0) and repetitive and restricted interests and behaviours (−1.08 [95% CI −2.17 to −0.01]; p = 0.05; I2 = 0). Populations with ASD have lower n-3 LCPUFA status and n-3 LCPUFA supplementation can potentially improve some ASD symptoms. Further research with large sample size and adequate study duration is warranted to confirm the efficacy of n-3 LCPUFA. PMID:28218722

  16. Traditional Dietary Pattern Increases Risk of Prostate Cancer in Argentina: Results of a Multilevel Modeling and Bias Analysis from a Case-Control Study

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    Camila Niclis

    2015-01-01

    Full Text Available There is increasing evidence that dietary habits play a role in prostate cancer (PC occurrence. Argentinean cancer risk studies require additional attention because of the singular dietary pattern of this population. A case-control study (147 PC cases, 300 controls was conducted in Córdoba (Argentina throughout 2008–2013. A principal component factor analysis was performed to identify dietary patterns. A mixed logistic regression model was applied, taking into account family history of cancer. Possible bias was evaluated by probabilistic bias analysis. Four dietary patterns were identified: Traditional (fatty red meats, offal, processed meat, starchy vegetables, added sugars and sweets, candies, fats, and vegetable oils, Prudent (nonstarchy vegetables, whole grains, Carbohydrate (sodas/juices and bakery products, and Cheese (cheeses. High adherence to the Traditional (OR 2.82, 95%CI: 1.569–5.099 and Carbohydrate Patterns (OR 2.14, 95%CI: 1.470–3.128 showed a promoting effect for PC, whereas the Prudent and Cheese Patterns were independent factors. PC occurrence was also associated with family history of PC. Bias adjusted ORs indicate that the validity of the present study is acceptable. High adherence to characteristic Argentinean dietary patterns was associated with increased PC risk. Our results incorporate original contributions to knowledge about scenarios in South American dietary patterns and PC occurrence.

  17. A hybrid Bayesian hierarchical model combining cohort and case-control studies for meta-analysis of diagnostic tests: Accounting for partial verification bias.

    Science.gov (United States)

    Ma, Xiaoye; Chen, Yong; Cole, Stephen R; Chu, Haitao

    2014-05-26

    To account for between-study heterogeneity in meta-analysis of diagnostic accuracy studies, bivariate random effects models have been recommended to jointly model the sensitivities and specificities. As study design and population vary, the definition of disease status or severity could differ across studies. Consequently, sensitivity and specificity may be correlated with disease prevalence. To account for this dependence, a trivariate random effects model had been proposed. However, the proposed approach can only include cohort studies with information estimating study-specific disease prevalence. In addition, some diagnostic accuracy studies only select a subset of samples to be verified by the reference test. It is known that ignoring unverified subjects may lead to partial verification bias in the estimation of prevalence, sensitivities, and specificities in a single study. However, the impact of this bias on a meta-analysis has not been investigated. In this paper, we propose a novel hybrid Bayesian hierarchical model combining cohort and case-control studies and correcting partial verification bias at the same time. We investigate the performance of the proposed methods through a set of simulation studies. Two case studies on assessing the diagnostic accuracy of gadolinium-enhanced magnetic resonance imaging in detecting lymph node metastases and of adrenal fluorine-18 fluorodeoxyglucose positron emission tomography in characterizing adrenal masses are presented.

  18. Application of nested PCR-DGGE (denaturing gradient gel electrophoresis) for the analysis of ciliate communities in soils.

    Science.gov (United States)

    Shimano, Satoshi; Sambe, Mitsuo; Kasahara, Yasuhiro

    2012-01-01

    Ciliates play important roles as prey and predators in ecosystems. Changes in the ciliate community can affect the composition and population of microfauna and microflora in ecosystems. To investigate the structure of ciliate communities, we developed a nested PCR-DGGE method, which combines a universal eukaryotic-specific primer set in the first PCR step with a ciliate-specific primer set in the second PCR step, to amplify 18S rRNA genes from ciliates. The 300 bp DGGE fragments generated more bands on the gel than the 600 bp DGGE fragments. Prior to bead beating, DNA extraction of ciliates from soil samples was optimized with a combination of freeze-thaw cycles and ultrasonication. We applied this nested PCR-DGGE method to agricultural soils amended with 0, 120, 300, and 600 t ha⁻¹ year⁻¹ of livestock slurry. The results from the DGGE profiles and principal component analysis (PCA) revealed that the supplement of slurry to soils influenced the ciliate communities. From phylogenetic analysis, 108 DGGE bands were assigned to six classes, which included Spirotrichea and Colpodea, of the subphylum Intramacronucleata, and one class of the subphylum Postciliodesmatophora. These results indicated that a wide variety of taxonomic groups were detected by DGGE profiling. Thus, the nested PCR-DGGE method described here could clearly differentiate between ciliate communities within soil samples and allowed for the phylogenetic identification of these ciliates at the class level.

  19. CD20-negative de novo diffuse large B-cell lymphoma in HIV-negative patients: A matched case-control analysis in a single institution

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    Li Ya-Jun

    2012-05-01

    Full Text Available Abstract Background HIV-negative, CD20-negative de novo diffuse large B-cell lymphoma (DLBCL patients has rarely been reported. To elucidate the nature of this entity, we retrospectively reviewed the data of 1,456 consecutive de novo DLBCL patients who were treated at Sun Yat-Sen University Cancer Center between January 1999 and March 2011. Methods The pathologic characteristics of CD20-negative patients, clinical features, response to initial treatment, and outcomes of 28 patients with available clinical data (n = 21 were reviewed. Then, a matched case-control (1:3 analysis was performed to compare patients with CD20-negative and -positive DLBCL. Results The median age of the 28 CD20-negative DLBCL patients was 48 years, with a male-female ratio of 20:8. Seventeen of 22 (77.3% CD20-negative DLBCL cases were of the non-germinal centre B-cell (non-GCB subtype. High Ki67 expression (≥80%, an index of cell proliferation, was demonstrated in 17 of 24 (70.8% cases. Extranodal involvement (≥ 1 site was observed in 76.2% of the patients. Following initial therapy, 9 of 21 (42.9% cases achieved complete remission, 4 (19% achieved partial remission, 1 (4.8% had stable disease, and 7 (33.3% had disease progression. The median overall survival was 23 months. The 3-year progression-free survival (PFS and overall survival (OS rates were 30.5% and 35%, respectively. A matched case-control analysis showed that patients with CD20-negative and -positive DLBCL did not exhibit a statistically significant difference with respect to the main clinical characteristics (except extranodal involvement, whereas the patients with CD20-positive DLBCL had a better survival outcome with 3-year PFS (P = 0.008 and OS (P = 0.008 rates of 52% and 74.1%, respectively. Conclusions This study suggests that HIV-negative, CD20-negative de novo DLBCL patients have a higher proportion of non-GCB subtype, a higher proliferation index, more frequent extranodal involvement, a poorer

  20. Association between chronic obstructive pulmonary disease and lung cancer: a case-control study in Southern Chinese and a meta-analysis.

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    Hui Wang

    Full Text Available BACKGROUND: Lung cancer and chronic obstructive pulmonary disease (COPD share a common risk factor in cigarette smoking and a large portion of patients with lung cancer suffer from COPD synchronously. We therefore hypothesized that COPD is an independent risk factor for lung cancer. Our aim was to investigate the intrinsic linkage of COPD (or emphysema, chronic bronchitis and asthma and lung cancer. METHODS: The present hospital-based case-control study included 1,069 patients with newly diagnosed lung cancer and 1,132 age frequency matched cancer-free controls. The odds ratios (ORs for the associations between each previous pulmonary disease and lung cancer were estimated with logistic regression models, adjusting for age, sex, family history of cancer, BMI and pack year smoking. In meta-analysis, the pooled effects of previous pulmonary diseases were analyzed with random effects models; and stratification analyses were conducted on smoking status and ethnicity. RESULTS: In the case-control study, previous COPD was associated with the odds for increased risk of lung cancer (OR = 1.29, 95% confidence interval [CI] = 1.00∼1.68; so were emphysema (OR = 1.55, 95%CI = 1.03∼2.32 and chronic bronchitis (OR = 1.22, 95%CI = 0.99∼1.67; while asthma was associated with odds for decreased risk of lung cancer (OR = 0.29, 95%CI = 0.16∼0.53. These associations were more pronounced in smokers (P<.05 for all strata, but not in non-smokers. In meta-analysis, 35 studies (22,010 cases and 44,438 controls were identified. COPD was significantly associated with the odds for increased risk of lung cancer (pooled OR = 2.76; 95% CI = 1.85-4.11, so were emphysema (OR = 3.02; 95% CI = 2.41-3.79 and chronic bronchitis (OR = 1.88; 95% CI = 1.49-2.36; and these associations were more pronounced in smokers than in non-smokers (P<.001 respectively. No significant association was observed for asthma. CONCLUSION: Previous COPD could increase the risk of lung cancer

  1. Relationship between tea consumption and pancreatic cancer risk: a meta-analysis based on prospective cohort studies and case-control studies.

    Science.gov (United States)

    Chen, Ke; Zhang, Qi; Peng, Min; Shen, Yanping; Wan, Peng; Xie, Guoming

    2014-09-01

    The aim of this study was to evaluate the relationship between regular tea consumption and the risk of pancreatic cancer by a meta-analysis. Two investigators independently performed a computer retrieve on the electronic databases of Embase, PubMed, and Ovidsp for prospective cohort studies and case-control studies on regular tea consumption and the risk of pancreatic cancer incidence. The keywords using for search were ('Pancreas' OR 'pancreatic') AND ('neoplasms' OR 'carcinoma' OR 'cancer') AND 'tea'. Risk ratios (RRs) and 95% confidence interval (CI) were used to determine the effect of tea consumption on pancreatic cancer. A total of 14 studies were included (8078 pancreatic cancer patients, with a total of 859 783 patients) in the present meta-analysis. The pooled results of effect size indicated that tea consumption has no significant relationship with risk of pancreatic cancer (RR=0.99, 95% CI: 0.89-1.11, P=0.922). However, the subgroup analysis of different countries showed a statistical decrease in pancreatic cancer risk by high consumption of tea in a Chinese population (RR=0.76, 95% CI: 0.59-0.98, P=0.036). Similar results were found in the elderly (>60 years old) (RR=0.76, 95% CI: 0.60-0.96, P=0.023). In conclusion, the present meta-analysis of 14 studies suggests that the correlation between tea consumption and the risk of pancreatic cancer in the general population is not significant, but an increase in tea consumption can reduce the risk of pancreatic cancer disease in Chinese populations and in individuals older than 60 years of age. It is necessary to formulate more rigorous designs of regional studies to further confirm the relationship between tea consumption and pancreatic cancer.

  2. Gene-expression analysis of single cells-nested polymerase chain reaction afte laser microdissection

    Institute of Scientific and Technical Information of China (English)

    Xin Shi; Jorg Kleeff; Zhao-Wen Zhu; Bruno Schmied; Wen-Hao Tang; Arthur Zimmermann; Markus W. Bucher; Helmut Friess

    2003-01-01

    AIM: The structural and functional characteristics of cells are dependent on the specific gene expression profile. The ability to study and compare gene expression at the cellular level will therefore provide valuable insights into cell physiology and pathophysiology. METHODS: Individual cells were isolated from frozen colon tissue sections using laser microdissection. DNA as well as RNA were extracted, and total RNA was reversely transcribed to complementary DNA (cDNA). Both DNA and cDNA were analyzed by nested polymerase chain reaction (PCR). The quality of isolated DNA and RNA was satisfactory. RESULTS: Single cells were successfully microdissected using an ultraviolet laser micromanipulator. Nested PCR amplification products of DNA and cDNA of single cells could clearly be visualized by agarose gel electrophoresis. CONCLUSION: The combined use of laser microdissection and nested-PCR provides an opportunity to analyze geneexpression in single cells. This method allows the analysisand identification of specific genes which are involved inphysiological and pathophysiological processes in a complexof variable cell phenotypes.

  3. Comparison of CATs, CURB-65 and PMEWS as triage tools in pandemic influenza admissions to UK hospitals: case control analysis using retrospective data.

    Science.gov (United States)

    Myles, Puja R; Nguyen-Van-Tam, Jonathan S; Lim, Wei Shen; Nicholson, Karl G; Brett, Stephen J; Enstone, Joanne E; McMenamin, James; Openshaw, Peter J M; Read, Robert C; Taylor, Bruce L; Bannister, Barbara; Semple, Malcolm G

    2012-01-01

    Triage tools have an important role in pandemics to identify those most likely to benefit from higher levels of care. We compared Community Assessment Tools (CATs), the CURB-65 score, and the Pandemic Medical Early Warning Score (PMEWS); to predict higher levels of care (high dependency--Level 2 or intensive care--Level 3) and/or death in patients at or shortly after admission to hospital with A/H1N1 2009 pandemic influenza. This was a case-control analysis using retrospectively collected data from the FLU-CIN cohort (1040 adults, 480 children) with PCR-confirmed A/H1N1 2009 influenza. Area under receiver operator curves (AUROC), sensitivity, specificity, positive predictive values and negative predictive values were calculated. CATs best predicted Level 2/3 admissions in both adults [AUROC (95% CI): CATs 0.77 (0.73, 0.80); CURB-65 0.68 (0.64, 0.72); PMEWS 0.68 (0.64, 0.73), ptools for predicting need for higher levels of care and/or mortality in patients of all ages.

  4. A meta-analysis of lesser prairie-chicken nesting and brood-rearing habitats: implications for habitat management

    Science.gov (United States)

    Hagen, Christian A.; Grisham, Blake A.; Boal, Clint W.; Haukos, David A.

    2013-01-01

    The distribution and range of lesser prairie-chicken (Tympanuchus pallidicinctus) has been reduced by >90% since European settlement of the Great Plains of North America. Currently, lesser prairie-chickens occupy 3 general vegetation communities: sand sagebrush (Artemisia filifolia), sand shinnery oak (Quercus havardii), and mixed-grass prairies juxtaposed with Conservation Reserve Program grasslands. As a candidate for protection under the Endangered Species Act, there is a need for a synthesis that characterizes habitat structure rangewide. Thus, we conducted a meta-analysis of vegetation characteristics at nest sites and brood habitats to determine whether there was an overall effect (Hedges' d) of habitat selection and to estimate average (95% CI) habitat characteristics at use sites. We estimated effect sizes (di) from the difference between use (nests and brood sites) and random sampling sites for each study (n = 14), and derived an overall effect size (d++). There was a general effect for habitat selection as evidenced by low levels of variation in effect sizes across studies and regions. There was a small to medium effect (d++) = 0.20-0.82) of selection for greater vertical structure (visual obstruction) by nesting females in both vegetation communities, and selection against bare ground (d++ = 0.20-0.58). Females with broods exhibited less selectivity for habitat components except for vertical structure. The variation of d++ was greater during nesting than brooding periods, signifying a seasonal shift in habitat use, and perhaps a greater range of tolerance for brood-rearing habitat. The overall estimates of vegetation cover were consistent with those provided in management guidelines for the species.

  5. Postoperative Complications of Laparoscopic Total Gastrectomy versus Open Total Gastrectomy for Gastric Cancer in a Meta-Analysis of High-Quality Case-Controlled Studies

    Directory of Open Access Journals (Sweden)

    Mikito Inokuchi

    2016-01-01

    Full Text Available Background. Some meta-analyses of case-controlled studies (CCSs have shown that laparoscopic or laparoscopy-assisted total gastrectomy (LTG had some short-term advantages over open total gastrectomy (OTG. However, postoperative complications differed somewhat among the meta-analyses, and some CCSs included in the meta-analyses had mismatched factors between LTG and OTG. Methods. CCSs comparing postoperative complications between LTG and OTG were identified in PubMed and Embase. Studies matched for patients’ status, tumor stage, and the extents of lymph-node dissection were included. Outcomes of interest, such as anastomotic, other intra-abdominal, wound, and pulmonary complications, were evaluated in a meta-analysis performed using Review Manager version 5.3 software. Result. This meta-analysis included a total of 2,560 patients (LTG, 1,073 patients; OTG, 1,487 patients from 15 CCSs. Wound complications were significantly less frequent in LTG than in OTG (n = 2,430; odds ratio [OR] 0.30, 95% confidence interval [CI] 0.29–0.85, P=0.01, I2 = 0%, and OR 0.46, 95% CI 0.17–0.52, P<0.0001, I2 = 0%. However, the incidence of anastomotic complications was slightly but not significantly higher in LTG than in OTG (n = 2,560; OR 1.44, 95% CI 0.96–2.16, P=0.08, I2 = 0%. Conclusion. LTG was associated with a lower incidence of wound-related postoperative complications than was OTG in this meta-analysis of CCSs; however, some concern remains about anastomotic problems associated with LTG.

  6. Prediabetes Is Associated with HNF-4α P2 Promoter Polymorphism rs1884613: A Case-Control Study in Han Chinese Population and an Updated Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Changyi Wang

    2014-01-01

    Full Text Available Background. Controversy remains for the association between hepatocyte nuclear factor 4α (HNF-4α P2 promoter polymorphism rs1884613 and type 2 diabetes (T2D. There was no association test of this polymorphism with prediabetes and T2D in the Chinese population. Moreover, an updated meta-analysis in various ethnic groups is needed to establish the contribution of rs1884613 to T2D risk. Methods. Using the Sequenom MassARRAY platform approach, we genotyped rs1884613 of HNF-4α in the P2 promoter region among 490 T2D patients, 471 individuals with prediabetes, and 575 healthy controls. All the individuals were recruited from 16 community health service centers in Nanshan district in Shenzhen province. Using STATA 11.0 software, meta-analysis was performed to summarize the overall contribution of rs1884613 to T2D risk. Results. Polymorphism rs1884613 was associated with genetic susceptibility to prediabetes in the whole samples (OR = 1.40, 95% CI = 1.16–1.68, P=0.0001 and the female subgrouped samples (OR = 1.48, 95% CI = 1.14–1.92, P=0.003 after adjusting for age and body mass index (BMI. In contrast, there was no association of rs1884613 with T2D in the whole samples and male in our case-control study and meta-analysis. Conclusions. Our results suggest that rs1884613 contributes to susceptibility to prediabetes, whereas this polymorphism may not play an important role in the development of T2D.

  7. Prediabetes Is Associated with HNF-4α P2 Promoter Polymorphism rs1884613: A Case-Control Study in Han Chinese Population and an Updated Meta-Analysis

    Science.gov (United States)

    Wang, Changyi; Chen, Sihan; Zhang, Tao; Chen, Zhongwei; Liu, Shengyuan; Peng, Xiaolin; Ma, Jianping; Zhong, Xiaohong; Yan, Yanqiong; Tang, Linlin; Mai, Yifeng; Han, Liyuan

    2014-01-01

    Background. Controversy remains for the association between hepatocyte nuclear factor 4α (HNF-4α) P2 promoter polymorphism rs1884613 and type 2 diabetes (T2D). There was no association test of this polymorphism with prediabetes and T2D in the Chinese population. Moreover, an updated meta-analysis in various ethnic groups is needed to establish the contribution of rs1884613 to T2D risk. Methods. Using the Sequenom MassARRAY platform approach, we genotyped rs1884613 of HNF-4α in the P2 promoter region among 490 T2D patients, 471 individuals with prediabetes, and 575 healthy controls. All the individuals were recruited from 16 community health service centers in Nanshan district in Shenzhen province. Using STATA 11.0 software, meta-analysis was performed to summarize the overall contribution of rs1884613 to T2D risk. Results. Polymorphism rs1884613 was associated with genetic susceptibility to prediabetes in the whole samples (OR = 1.40, 95% CI = 1.16–1.68, P = 0.0001) and the female subgrouped samples (OR = 1.48, 95% CI = 1.14–1.92, P = 0.003) after adjusting for age and body mass index (BMI). In contrast, there was no association of rs1884613 with T2D in the whole samples and male in our case-control study and meta-analysis. Conclusions. Our results suggest that rs1884613 contributes to susceptibility to prediabetes, whereas this polymorphism may not play an important role in the development of T2D. PMID:25400315

  8. Nasopharyngeal Case-Control Study

    Science.gov (United States)

    A case-control study conducted in Taiwan between 1991-1994 among approximately 1,000 individuals to examine the role of viral, environmental, and genetic factors associated with the development of nasopharyngeal carcinoma

  9. A nested case-control study on the influencing factors of tuberculosis among people living with HIV/AIDS in Hunan province%湖南省HIV/AIDS人群结核发病影响因素的巢式病例对照研究

    Institute of Scientific and Technical Information of China (English)

    陈梦施; 杨华林; 陈艳芳; 谭红专; 白丽琼; 张艳辉; 刘军; 李桂平

    2010-01-01

    Objective To determine the risk factors related to tuberculosis infection among people living with HIV/AIDS and to develop strategies for preventing the co-infection.Methods A 1:2matched nested case-control study was carried out to analyze the influencing factors of tuberculosis among people living with HIV/AIDS.Results 1018 people living with HIV/AIDS were followed up for one year with a total number of 736.75 person-years,among them 62 tuberculosis cases were diagnosed.The incidence density of tuberculosis among people living with HIV/AIDS was 8.42 persons per 100 person-years.Factors as education level(OR=0.483),vaccination history of Bacille Calmette Guerin(OR=0.561),CD_4~+ count T-lymphocyte(OR=0.356),unemployment(OR=1.976),living alone(OR=2.646),and smoking(OR=2.215)were significantly related to the prevalence of tuberculosis among people living with HIV/AIDS.Conclusion High education level,with vaccination history of Bacille Calmette Guerin and high level of CD_4~+ T-lymphocyte count were protective factors while being unemployed,living alone,and smoking habit were risk factors related to the prevalence of tuberculosis among people living with HIV/AIDS.%目的 探讨HIV/AIDS人群发生结核病的危险因素.方法 采用1:2匹配的巢式病例对照研究方法分析HIV/AIDS人群发生结核的危险因素.结果 对1018例未患结核的HIV/AIDS人群随访观察1年,累计观察736.75人年,共检查出结核病患者62例,HIV/AIDS人群结核病发病密度为8.42人/100人年(62人/736.75人年).文化程度(OR=0.483)、卡介苗接种史(OR=0.561)、CD_4~+T淋巴细胞数(OR=0.356)、无业(OR=1.976)、单身(OR=2.646)和吸烟(OR=2.215)等因素与HIV/AIDS人群发生结核病有关.结论 文化程度高、有卡介苗接种史和CD_4~+T淋巴细胞数高是HIV/AIDS人群患结核病的保护因素;无业、单身和吸烟是HIV/AIDS人群患结核病的危险因素.

  10. A nested case-control study on the relationship between depression and relapse in patients with condyloma acuminatum%尖锐湿疣患者的抑郁情绪与治疗后复发关联的巢式病例对照研究

    Institute of Scientific and Technical Information of China (English)

    姚海燕; 郑莉; 包满珍

    2011-01-01

    Objective To explore the relationship between depression and relapse irt patients with condyloma acuminatum (CA) prospectively.Methods Using nested case-control study, the depression score was measured prospectively in a CA patient cohort, and 46 cases with relapse of CA and 46 controls without relapse of CA matched for gender and age ( ± 5 a) were recruited in follow-up phase.Conditional Logistic regression models were constructed to estimate OR and 95% CI.Results Compared with matched controls, the cases with relapse of CA in 3 month follow-up phase showed higher depression score significantly (t = 6.77, P< 0.001 ).After adjustment for the course of the disease, mild depression ( OR = 1.13,95 % CI = 1.01 ~ 1.58), moderate depression ( OR = 2.31,95% CI = 1.12 ~ 2.84), and major depression ( OR = 4.1O,95% CI = 2.69~ 5.85 ) were significantly associated with relapse of CA and a clear dose-response effect was also observed.Conclusions The prevention and treatment of depression are beneficial to the decrease of relapse incidence in patients with CA.%目的 前瞻性地探讨尖锐湿疣(condyloma acuminatum,CA)患者就诊时的抑郁状态与治疗后复发的关系.方法 采用巢氏病例对照研究的方法,先对160名门诊接受治疗的CA患者近1周的抑郁状态进行测定,并采用抑郁自评量表进行评分,以3个月随诊期间出现的46名CA复发患者组成病例组,从同期未复发的患者中选择对照,对照与病例按1∶1匹配性别、年龄(±5岁).应用条件Logistic回归模型计算OR值及其95% CI,分析就诊时CA患者的抑郁状态与治疗后病情复发的关系.结果 CA复发病例的抑郁评分高于同期未复发病例的抑郁评分,且差异有统计学意义(t=6.77,P<0.001).调整病程对抑郁与CA复发可能造成的影响后,轻度抑郁(50~59)、中度抑郁(60~69)和重度抑郁(70~)与CA复发关联的OR值及95% CI分别为1.13(1.01~1.58)、2.31(1.12~2.84)和4.10(2.69~5

  11. Exposure to ionizing radiation during dental X-rays is not associated with risk of developing meningioma: a meta-analysis based on seven case-control studies.

    Directory of Open Access Journals (Sweden)

    Ping Xu

    Full Text Available Many observational studies have found that exposure to dental X-rays is associated with the risk of development of meningioma. However, these findings are inconsistent. We conducted a meta-analysis to assess the relationship between exposure to dental X-rays and the risk of development of meningioma.The PubMed and EMBASE databases were searched to identify eligible studies. Summary odds ratio (OR estimates and 95% confidence intervals (95% CIs were used to compute the risk of meningioma development according to heterogeneity. Subgroup and sensitivity analyses were performed to further explore the potential heterogeneity. Finally, publication bias was assessed.Seven case-control studies involving 6,174 patients and 19,459 controls were included in the meta-analysis. Neither exposure to dental X-rays nor performance of full-mouth panorex X-rays was associated with an increased risk of development of meningioma (overall: OR, 0.97; 95% CI, 0.70-1.32; dental X-rays: OR, 1.05; 95% CI, 0.89-1.25; panorex X-rays: OR, 1.01; 95% CI, 0.76-1.34. However, exposure to bitewing X-rays was associated with a slightly increased risk of development of meningioma (OR, 1.73; 95% CI, 1.28-2.34. Similar results were obtained in the subgroup and sensitivity analyses. Little evidence of publication bias was observed.Based on the currently limited data, there is no association between exposure to dental X-rays and the risk of development of meningioma. However, these results should be cautiously interpreted because of the heterogeneity among studies. Additional large, high-quality clinical trials are needed to evaluate the association between exposure to dental X-rays and the risk of development of meningioma.

  12. Multistate nested canalizing functions

    CERN Document Server

    Adeyeye, J O; Laubenbacher, R; Li, Y

    2013-01-01

    The concept of a nested canalizing Boolean function has been studied over the course of the last decade in the context of understanding the regulatory logic of molecular interaction networks, such as gene regulatory networks. Such functions appear preferentially in published models of such networks. Recently, this concept has been generalized to include multi-state functions, and a recursive formula has been derived for their number, as a function of the number of variables. This paper carries out a detailed analysis of the class of nested canalizing functions over an arbitrary finite field. Furthermore, the paper generalizes the concept further, and derives a closed formula for the number of such generalized functions. The paper also derives a closed formula for the number of equivalence classes under permutation of variables. This is motivated by the fact that two nested canalizing functions that differ by a permutation of the variables share many important properties with each other. The paper contributes ...

  13. Comparison of CATs, CURB-65 and PMEWS as triage tools in pandemic influenza admissions to UK hospitals: case control analysis using retrospective data.

    Directory of Open Access Journals (Sweden)

    Puja R Myles

    Full Text Available Triage tools have an important role in pandemics to identify those most likely to benefit from higher levels of care. We compared Community Assessment Tools (CATs, the CURB-65 score, and the Pandemic Medical Early Warning Score (PMEWS; to predict higher levels of care (high dependency--Level 2 or intensive care--Level 3 and/or death in patients at or shortly after admission to hospital with A/H1N1 2009 pandemic influenza. This was a case-control analysis using retrospectively collected data from the FLU-CIN cohort (1040 adults, 480 children with PCR-confirmed A/H1N1 2009 influenza. Area under receiver operator curves (AUROC, sensitivity, specificity, positive predictive values and negative predictive values were calculated. CATs best predicted Level 2/3 admissions in both adults [AUROC (95% CI: CATs 0.77 (0.73, 0.80; CURB-65 0.68 (0.64, 0.72; PMEWS 0.68 (0.64, 0.73, p<0.001] and children [AUROC: CATs 0.74 (0.68, 0.80; CURB-65 0.52 (0.46, 0.59; PMEWS 0.69 (0.62, 0.75, p<0.001]. CURB-65 and CATs were similar in predicting death in adults with both performing better than PMEWS; and CATs best predicted death in children. CATs were the best predictor of Level 2/3 care and/or death for both adults and children. CATs are potentially useful triage tools for predicting need for higher levels of care and/or mortality in patients of all ages.

  14. Obsessive-Compulsive Disorder and quality of life outcomes: protocol for a systematic review and meta-analysis of cross-sectional case-control studies

    Directory of Open Access Journals (Sweden)

    Anna Coluccia

    2015-06-01

    Full Text Available Background. Obsessive-compulsive Disorder (OCD is a chronic disabling psychological condition, which can severely affect quality of life (QOL. Growing interest has been dedicated to assessing which domains of QOL are more severely affected in patients with OCD. However, research yielded conflicting findings. Investigating QOL in OCD could suggest the need for integration of interventions aimed at improving those specific domains more severely impaired by obsessions and compulsions.Methods. We will conduct a systematic review of cross-sectional case-control studies according to PRISMA guidelines, where patients with a primary OCD diagnosis were compared on QOL outcomes with healthy controls. Primary objectives will be to examine differences in QOL outcomes between patients with OCD and healthy controls, and to assess which QOL domains are more severely impaired in patients compared with controls, particularly subjective well-being, social and interpersonal functioning, work functioning, and family functioning. Subsequently, the study will investigate potential moderators of QOL in OCD, including participants characteristics (age, sex, presence of comorbid personality disorders, OCD symptom severity, severity of concurrent depressive symptoms, duration of OCD symptoms, and generational cohort, and study characteristics (date of publication and methodological quality of the studies. Online databases will be searched (PsycINFO, PubMED, Science Direct, Cinahl, Biological Abstracts, Psyclit, Embase, The Cochrane Central Register of Controlled Trials, and Google Scholar. To locate unpublished records, conference abstracts, doctoral dissertations and theses will be handsearched, and experts will be contacted. Statistical analyses will be performed though random effect model meta-analysis. Risk of bias assessments will be conducted using the instrument Methodological Index for Non-Randomized Studies.

  15. Single nucleotide polymorphisms in candidate genes and dengue severity in children: a case-control, functional and meta-analysis study.

    Science.gov (United States)

    Xavier-Carvalho, Caroline; Gibson, Gerusa; Brasil, Patrícia; Ferreira, Ralph X; de Souza Santos, Reinaldo; Gonçalves Cruz, Oswaldo; de Oliveira, Solange Artimos; de Sá Carvalho, Marília; Pacheco, Antonio G; Kubelka, Claire F; Moraes, Milton O

    2013-12-01

    Dengue is an arthropod-borne emerging viral disease with high morbidity and mortality risk in tropical countries like Brazil. Clinical manifestations are vast, ranging from asymptomatic to most severe forms of dengue such as shock. Previous data have shown that host genetics play a role in disease susceptibility and severity. Herein, we have tested the association of single nucleotide polymorphisms (SNPs) at TNF, IL10, MIF, DCSIGN, CLEC5A, NOD2, CCR5 and MRC1 as candidate genes using a matched case-control study design including 88 severe children cases of dengue patients and 335 healthy unrelated subjects that was also separated in IgG(+) and IgG(-) controls. We demonstrated that the TT genotype of CLEC5A SNP (rs1285933 C>T) is associated with dengue severity (OR=2.25; p=0.03) and that GG genotype of -336G>A DCSIGN (CD209) SNP is associated with protection to severe dengue (OR=0.12; p=0.04). Both comparisons were borderline significant when cases were compared with IgG(+) controls subgroup. Nevertheless, genotype-phenotype correlation was also assessed using serum levels of TNF from infected patients at the onset of dengue fever, and CT/TT carriers in CLEC5A secreted higher levels of TNF than CC individuals in 5-7 days of infection. No significant difference was observed in TNF levels between genotypes GG versus AG/AA at DCSIGN promoter. Next, we performed a meta-analysis retrieving results from the literature for -336G>A DCSIGN and -308G>A TNF SNPs demonstrating that the consensus estimates of these SNPs indicated no association with dengue severity (when compared to Dengue fever) in the overall analysis. But, a subgroup analysis in the -336G>A DCSIGN, the G allele was associated with severe dengue susceptibility in Asians (ORallele=2.77; p=0.0001; ORcarriers=2.99; p=0.0001) and protection in Brazilians (ORallele=0.66; p=0.013). In summary, our results suggest that genetic variations at CLEC5A increase the risk and regulate TNF secretion in dengue severity among

  16. Interpreting forest and grassland biome productivity utilizing nested scales of image resolution and biogeographical analysis

    Science.gov (United States)

    Iverson, Louis R.; Cook, Elizabeth A.; Graham, Robin L.; Olson, Jerry S.; Frank, Thomas; Ke, Ying; Treworgy, Colin; Risser, Paul G.

    1987-01-01

    This report summarizes progress made in our investigation of forest productivity assessment using TM and other biogeographical data during the third six-month period of the grant. Data acquisition and methodology hurdles are largely complete. Four study areas for which the appropriate TM and ancillary data were available are currently being intensively analyzed. Significant relationships have been found on a site by site basis to suggest that forest productivity can be qualitatively assessed using TM band values and site characteristics. Perhaps the most promising results relate TM unsupervised classes to forest productivity, with enhancement from elevation data. During the final phases of the research, multi-temporal and regional comparisons of results will be addressed, as well as the predictability of forest productivity patterns over a large region using TM data and/or TM nested within AVHRR data.

  17. Nested PCR for detection and genotyping of Ehrlichia ruminantium: use in genetic diversity analysis.

    Science.gov (United States)

    Martinez, Dominique; Vachiéry, Nathalie; Stachurski, Frederic; Kandassamy, Yane; Raliniaina, Modestine; Aprelon, Rosalie; Gueye, Arona

    2004-10-01

    Ehrlichia ruminantium, the agent of cowdriosis transmitted by Amblyomma ticks, presents an extensive genetic and antigenic diversity of key importance for vaccine formulation. Two means of nested polymerase chain reaction (PCR) targeting were developed to conduct molecular epidemiology studies in the Caribbean and Africa. The first used a conserved DNA fragment for detection of the pathogen in animals and vectors, and the second relied on the polymorphic map1 gene for genotyping. As compared to a PCR, the nested PCR showed a 2-Log10 improvement of sensitivity and allowed amplification from ticks, blood, brain, and lungs from infected animals, providing a more accurate picture of the tick infection rate. In Guadeloupe, this rate reached 36% (N = 212) instead of 1.7% (N = 224), as previously estimated. Genetic typing was done by restriction fragment length polymorphism or sequencing of map1 amplification products. Molecular epidemiology studies conducted in field sites selected for vaccination trials with inactivated vaccine, revealed the circulation of genetically divergent strains in limited geographical areas. It is known, then, that genetic clustering based on map1 has no predictive value regarding the protective value of a given strain against a new strain. However, tracing the strains by this technique revealed the extent of E. ruminantium diversity that one can expect in a given region, and the method allows differentiation between an inadequate immune response and the challenge by a breakthrough strain on animals dying despite vaccination. Up to now, genetic typing does not avoid cross-protection studies, which were conducted in parallel, although on a more limited scale. The importance of pathogen diversity studies for optimization of vaccine design is discussed as well as the research for new polymorphic genes. These genes may allow better predictions on cross-protection, given the recent completion of the sequence of the full genome of two E. ruminantium

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

    NARCIS (Netherlands)

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

    2008-01-01

    Ghrelin, an endogenous ligand for the growth hormone secretagogue receptor, has two major functions: the stimulation of the growth hormone production and the stimulation of food intake. Accumulating evidence also suggests a role of ghrelin in cancer development. We conducted a case-control study on

  19. Clinical outcomes of osteonecrosis of the femoral head after autologous bone marrow stem cell implantation: a meta-analysis of seven case-control studies.

    Science.gov (United States)

    Yuan, Heng-Feng; Zhang, Jing; Guo, Chang-An; Yan, Zuo-Qin

    2016-02-01

    The purpose of this study was to evaluate the clinical outcomes of osteonecrosis of the femoral head after autologous bone marrow stem cell implantation. We searched the PubMed, Embase and Web of Science databases and included all case-control trials that reported on the clinical outcomes of osteonecrosis progression, incidence of total hip arthroplasty and improvement in Harris hip scores. Overall, seven case-control trials were included. Compared with the controls, patients treated with the bone marrow stem cells implantation treatment showed improved clinical outcomes with delayed osteonecrosis progression (odds ratio = 0.17, 95% CI: 0.09 - 0.32; p osteonecrosis of the femoral, resulting in beneficial clinical outcomes. However, trials with larger sample sizes are needed to confirm these findings.

  20. American Samoa ESI: NESTS (Nest Points)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for nesting birds in American Samoa. Vector points in this data set represent locations of nesting...

  1. Risk factors for ectopic pregnancy: a comprehensive analysis based on a large case-control, population-based study in France.

    OpenAIRE

    BOUYER, Jean; Coste, Joël; Shojaei, Taraneh; Pouly, Jean-Luc; Fernandez, Hervé; Gerbaud, Laurent; Job-Spira, Nadine

    2003-01-01

    This case-control study was associated with a regional register of ectopic pregnancy between 1993 and 2000 in France. It included 803 cases of ectopic pregnancy and 1,683 deliveries and was powerful enough to investigate all ectopic pregnancy risk factors. The main risk factors were infectious history (adjusted attributable risk = 0.33; adjusted odds ratio for previous pelvic infectious disease = 3.4, 95% percent confidence interval (CI): 2.4, 5.0) and smoking (adjusted attributable risk = 0....

  2. ZDHHC8 as a candidate gene for schizophrenia: Analysis of a putative functional intronic marker in case-control and family-based association studies

    Directory of Open Access Journals (Sweden)

    Jabs Burkhard

    2005-10-01

    Full Text Available Abstract Background The chromosome 22q11 region is proposed as a major candidate locus for susceptibility genes to schizophrenia. Recently, the gene ZDHHC8 encoding a putative palmitoyltransferase at 22q11 was proposed to increase liability to schizophrenia based on both animal models and human association studies by significant over-transmission of allele rs175174A in female, but not male subjects with schizophrenia. Methods Given the genetic complexity of schizophrenia and the potential genetic heterogeneity in different populations, we examined rs175174 in 204 German proband-parent triads and in an independent case-control study (schizophrenic cases: n = 433; controls: n = 186. Results In the triads heterozygous parents transmitted allele G preferentially to females, and allele A to males (heterogeneity χ2 = 4.43; p = 0.035. The case-control sample provided no further evidence for overall or gender-specific effects regarding allele and genotype frequency distributions. Conclusion The findings on rs175174 at ZDHHC8 are still far from being conclusive, but evidence for sexual dimorphism is moderate, and our data do not support a significant genetic contribution of rs175174 to the aetiopathogenesis of schizophrenia.

  3. Protective and risk factors in amateur equestrians and description of injury patterns: A retrospective data analysis and a case - control survey

    Directory of Open Access Journals (Sweden)

    Schötzau Andreas

    2011-02-01

    Full Text Available Abstract Background In Switzerland there are about 150,000 equestrians. Horse related injuries, including head and spinal injuries, are frequently treated at our level I trauma centre. Objectives To analyse injury patterns, protective factors, and risk factors related to horse riding, and to define groups of safer riders and those at greater risk Methods We present a retrospective and a case-control survey at conducted a tertiary trauma centre in Bern, Switzerland. Injured equestrians from July 2000 - June 2006 were retrospectively classified by injury pattern and neurological symptoms. Injured equestrians from July-December 2008 were prospectively collected using a questionnaire with 17 variables. The same questionnaire was applied in non-injured controls. Multiple logistic regression was performed, and combined risk factors were calculated using inference trees. Results Retrospective survey A total of 528 injuries occured in 365 patients. The injury pattern revealed as follows: extremities (32%: upper 17%, lower 15%, head (24%, spine (14%, thorax (9%, face (9%, pelvis (7% and abdomen (2%. Two injuries were fatal. One case resulted in quadriplegia, one in paraplegia. Case-control survey 61 patients and 102 controls (patients: 72% female, 28% male; controls: 63% female, 37% male were included. Falls were most frequent (65%, followed by horse kicks (19% and horse bites (2%. Variables statistically significant for the controls were: Older age (p = 0.015, male gender (p = 0.04 and holding a diploma in horse riding (p = 0.004. Inference trees revealed typical groups less and more likely to suffer injury. Conclusions Experience with riding and having passed a diploma in horse riding seem to be protective factors. Educational levels and injury risk should be graded within an educational level-injury risk index.

  4. Nested Fixed Depth Fluidic Sampler and At Tank Analysis System Deployment Strategy and Plan

    Energy Technology Data Exchange (ETDEWEB)

    REICH, F.R.

    2000-02-01

    Under the Hanford Site River Protection Project (RPP) privatization strategy, the U.S. Department of Energy (DOE) Office of River Protection (ORP) requires the CH2M Hill Hanford Group, Inc. (CHG) to supply tank waste to the privatization contractor, BNFL Inc. (BNFL), for separation and/or treatment and immobilization (vitrification). Three low-activity waste (LAW) specification envelopes represent the range of liquid waste types in the large, Hanford Site underground waste storage tanks. The CHG also is expected to supply high-level waste (HLW) separation and/or treatment and disposal. The HLW envelope is an aqueous slurry of insoluble suspended solids (sludge). The Phase 1 demonstration will extend over 24 years (1996 through 2019) and will be used to resolve technical uncertainties. About one-tenth of the total Hanford Site tank waste, by mass, will be processed during this period. This document provides a strategy and top-level implementation plan for demonstrating and deploying an alternative sampling technology. The alternative technology is an improvement to the current grab sampling and core sampling approaches that are planned to be used to support the RPP privatization contract. This work also includes adding the capability for some at-tank analysis to enhance the potential of this new technology to meet CHG needs. The first application is to LAW and HLW feed staging for privatization; the next is to support cross-site waste transfer from 200 West Area tanks.

  5. A nested case-control study on the relationship between occupational physical activity,heredity factors and metabolic syndrome%职业体力活动和遗传因素与代谢综合征关系的巢式病例对照研究

    Institute of Scientific and Technical Information of China (English)

    董建梅; 王临池; 陈秋; 俞浩; 杨婕; 郭志荣; 武鸣; 陈晓东

    2010-01-01

    with eases by region,gender and age (±2 years).In total,389 MS patients and 389 eontrols were recruited as study subjects.Nested ease-control study was applied for the present analysis.TaqMan fluorescence probe method was used to detect the genetic polymorphism of PPARα intron 1A/C (rs135539).Results (1)Compared to low physical activity group,the subjects with heavy physical activity were positively associated with MS (OR=2.18,95%CI:1.08-4.38).(2)The subjects,with a family history of hypertension (OR= 1.44,95% CI:1.02-2.03 )or type 2 diabetes (OR=3.25,95CI:1.28-8.20),were significantly indreased the occurrence of MS.(3)The genotype(AA,AC,CC) of PPARα intron 1A/C was not found to be related to MS.The OR of AC and CC genotype (compared to the genotype AA) were 0.98(95%CI:0.70-1.36) and 0.75 (95% CI:0.44-1.29) ,respectively.(4) Effect modifications were observed between family history of hypertension and moderate physical activity (OR=2.47,95% CI:1.00-6.06 ) or heavy physical activity (OR=3.82,95%CI:1.31-11.15) on the development of MS.Conclusion Heavy physical activity,with family history of hypertension or type 2 diabetes,seemed to be positively correlated with the risk of MS.Effect modifications were observed between occupational physical activity and family history of hypertension which might be associated with an increased risk of MS.

  6. Simulated nest study guide

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The instructions outlined here will provide uniform methods for measuring total predator activity in blocks of nesting cover or at special kinds of nest sites. The...

  7. Recruitment study nest card

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is a survey on waterfowl nests in Stillwater Wildlife Management Area. Visits were made to each nest on an approximately weekly basis, and the stage of the eggs...

  8. -251 T/A polymorphism of the interleukin-8 gene and cancer risk: a HuGE review and meta-analysis based on 42 case-control studies.

    Science.gov (United States)

    Wang, Na; Zhou, Rongmiao; Wang, Chunmei; Guo, Xiaoqing; Chen, Zhifeng; Yang, Shan; Li, Yan

    2012-03-01

    The -251T/A (rs4073), a single nucleotide polymorphism, has been identified in the promoter region of the interleukin-8 (IL-8) gene. It's presence could influence the production of IL-8 protein by regulating the transcriptional activity of the gene. A large number of studies have been performed to evaluate the role of -251T/A polymorphism on various cancers, with inconsistent results being reported. In this paper, we summarized 13,189 cases and 16,828 controls from 42 case-control studies and attempted to assess the susceptibility of -251T/A polymorphism to cancers by a comprehensive meta-analysis. Pooled odds ratios and 95% confidence intervals were calculated by using the random-effects model. Publication bias, subgroup, and sensitivity analysis were also performed. Results showed that the carriers of the -251A allele had about a 12-21% increased risk for the reviewed cancer, in total. The carriers of -251A had an elevated risk to breast cancer, gastric cancer and nasopharyngeal cancer and a reduced risk to prostate cancer, but no evidence was found to indicate that the -251A allele predisposed its carriers to colorectal and lung cancers. When stratified separately by 'racial descent' and 'study design', it was found that the carriers of the -251A allele among the African group, Asian group and hospital-based case-control study group were at a higher risk for cancer, but not in European group and population-based case-control study. These results show that -251A allele is susceptible in the development of low-penetrance cancers.

  9. Seismicity and Attenuation Correlation Analysis in the Bucaramanga Nest (Colombia). A Test for the Brittle-Ductile Interaction Hypothesis

    Science.gov (United States)

    Tarela, E.; Pujades, L. G.; Ugalde, A.

    2008-12-01

    Technical advances are nowadays starting to provide data sets covering large enough time windows and allowing studying the time evolution of several seismic parameters with some perspective. We study here, at a local scale, the following items: 1) the time evolution of two of these parameters, the seismicity and the coda-wave-attenuation, 2) their relationship in order to test the brittle-ductile interaction hypothesis of the lithosphere-asthenosphere complex system, and 3) its possible use as a mid-term predictor. Seismicity represents the brittle zone stress state, while the one of the ductile zone is characterized by the attenuation of coda waves, which here is measured through coda-Q quality factor. According to the model, the time series will present a similar variation rate during the calm period of the cycle. About two years before a major earthquake takes place in the region, the stress state of both the brittle and the ductile parts of the lithosphere-asthenosphere system would change and the correlation between the two parameters would break down because of this uncoupling. So, a correlation analysis of the two time series would lead to a mid- term prediction. The method is applied in a region with a complex and deep seismicity; this is, the Nest of Bucaramanga (Colombia). The seismic catalogue and waveforms for the attenuation analysis are obtained from Ingeominas; the catalogue includes 13629 events with local magnitude ML>3, fulfilling the magnitude completeness conditions. The seismic attenuation data are obtained from waveforms that have been selected between more than 17000 short period vertical seismograms, recorded at Barichara station, which is located right over the seismic nest. Over 3600 of these waveforms fulfil the magnitude completeness conditions, happened at hypocentral distances smaller than 150km and give coda Q fitting values with correlation coefficients r2≥0.7 So, for the time evolution we were able to average over 50 values of Q0

  10. Columbia River ESI: NESTS (Nest Points)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for bird nesting sites in the Columbia River area. Vector points in this data set represent locations of...

  11. A Higher Proportion of Metabolic Syndrome in Chinese Subjects with Sleep-Disordered Breathing: A Case-Control Study Based on Electrocardiogram-Derived Sleep Analysis

    Science.gov (United States)

    Tseng, Ping-Huei; Lee, Pei-Lin; Hsu, Wei-Chung; Ma, Yan; Lee, Yi-Chia; Chiu, Han-Mo; Ho, Yi-Lwun; Chen, Ming-Fong; Wu, Ming-Shiang; Peng, Chung-Kang

    2017-01-01

    Objective The prevalence of metabolic syndrome (MS) has increased rapidly in Taiwan and worldwide. We aim to determine the association between sleep-disordered breathing (SDB) and MS in a Chinese general population. Methods This case-control study recruited subjects who have undergone a prospective electrocardiogram-based cardiopulmonary coupling (CPC) sleep spectrogram as part of the periodic health check-ups at the National Taiwan University Hospital. Comprehensive anthropometrics, blood biochemistry, prevalence of MS and its individual components were compared with Bonferroni correction between 40 subjects with SDB, defined as the CPC-derived apnea–hypopnea index (CPC-AHI) >5 event/hour and 80 age- and sex-matched controls, defined as CPC-AHI <1 event/hour. MS was diagnosed based on the Adult Treatment Panel III, with a modification of waist circumference for Asians. Results Subjects with SDB were more obese with larger waist circumferences (95.1±12.9 vs. 87.3±6.9, P < .001) and borderline higher BMI (27.0±4.9 vs. 24.3±2.5, P = .002). Waist circumference was independently associated with the presence of SDB after adjustment for BMI, systolic blood pressure and fasting blood glucose in multiple regression analyses. Subjects with SDB had a higher prevalence of central obesity (72.5% vs. 42.5%, P = .002), hyperglycemia (45.0% vs. 26.3%, P = .04), MS (45.0% vs. 22.5%, P = .01) and number of MS components (2.4 ± 1.6 vs. 1.7 ± 1.4, P = .01) than the control group. Waist circumference was significantly correlated with both CPC-AHI (r = .492, P = .0013) and PSG-AHI (r = .699, P < .0001) in the SDB group. Conclusions SDB was associated with a higher prevalence of MS and its individual components, notably central obesity, in a Chinese general population. Large-scale screening of high risk population with MS to identify subjects with SDB for appropriate management is warranted. PMID:28081171

  12. PyMultiNest: Python interface for MultiNest

    Science.gov (United States)

    Buchner, Johannes

    2016-06-01

    PyMultiNest provides programmatic access to MultiNest (ascl:1109.006) and PyCuba, integration existing Python code (numpy, scipy), and enables writing Prior & LogLikelihood functions in Python. PyMultiNest can plot and visualize MultiNest's progress and allows easy plotting, visualization and summarization of MultiNest results. The plotting can be run on existing MultiNest output, and when not using PyMultiNest for running MultiNest.

  13. Automated Forensic Animal Family Identification by Nested PCR and Melt Curve Analysis on an Off-the-Shelf Thermocycler Augmented with a Centrifugal Microfluidic Disk Segment.

    Science.gov (United States)

    Keller, Mark; Naue, Jana; Zengerle, Roland; von Stetten, Felix; Schmidt, Ulrike

    2015-01-01

    Nested PCR remains a labor-intensive and error-prone biomolecular analysis. Laboratory workflow automation by precise control of minute liquid volumes in centrifugal microfluidic Lab-on-a-Chip systems holds great potential for such applications. However, the majority of these systems require costly custom-made processing devices. Our idea is to augment a standard laboratory device, here a centrifugal real-time PCR thermocycler, with inbuilt liquid handling capabilities for automation. We have developed a microfluidic disk segment enabling an automated nested real-time PCR assay for identification of common European animal groups adapted to forensic standards. For the first time we utilize a novel combination of fluidic elements, including pre-storage of reagents, to automate the assay at constant rotational frequency of an off-the-shelf thermocycler. It provides a universal duplex pre-amplification of short fragments of the mitochondrial 12S rRNA and cytochrome b genes, animal-group-specific main-amplifications, and melting curve analysis for differentiation. The system was characterized with respect to assay sensitivity, specificity, risk of cross-contamination, and detection of minor components in mixtures. 92.2% of the performed tests were recognized as fluidically failure-free sample handling and used for evaluation. Altogether, augmentation of the standard real-time thermocycler with a self-contained centrifugal microfluidic disk segment resulted in an accelerated and automated analysis reducing hands-on time, and circumventing the risk of contamination associated with regular nested PCR protocols.

  14. Joint-multiple family linkage analysis predicts within-family variation better than single-family analysis of the maize nested association mapping population.

    Science.gov (United States)

    Ogut, F; Bian, Y; Bradbury, P J; Holland, J B

    2015-06-01

    Quantitative trait locus (QTL) mapping has been used to dissect the genetic architecture of complex traits and predict phenotypes for marker-assisted selection. Many QTL mapping studies in plants have been limited to one biparental family population. Joint analysis of multiple biparental families offers an alternative approach to QTL mapping with a wider scope of inference. Joint-multiple population analysis should have higher power to detect QTL shared among multiple families, but may have lower power to detect rare QTL. We compared prediction ability of single-family and joint-family QTL analysis methods with fivefold cross-validation for 6 diverse traits using the maize nested association mapping population, which comprises 25 biparental recombinant inbred families. Joint-family QTL analysis had higher mean prediction abilities than single-family QTL analysis for all traits at most significance thresholds, and was always better at more stringent significance thresholds. Most robust QTL (detected in >50% of data samples) were restricted to one family and were often not detected at high frequency by joint-family analysis, implying substantial genetic heterogeneity among families for complex traits in maize. The superior predictive ability of joint-family QTL models despite important genetic differences among families suggests that joint-family models capture sufficient smaller effect QTL that are shared across families to compensate for missing some rare large-effect QTL.

  15. Nested Canalizing Functions and Their Networks

    CERN Document Server

    Kadelka, Claus; Adeyeye, John O; Laubenbacher, Reinhard

    2014-01-01

    The concept of a nested canalizing Boolean function has been studied over the last decade in the context of understanding the regulatory logic of molecular interaction networks, such as gene regulatory networks. Such networks are predominantly governed by nested canalizing functions. Derrida values are frequently used to analyze the robustness of a Boolean network to perturbations. This paper introduces closed formulas for the calculation of Derrida values of networks governed by Boolean nested canalizing functions, which previously required extensive simulations. Recently, the concept of nested canalizing functions has been generalized to include multistate functions, and a recursive formula has been derived for their number, as a function of the number of variables. This paper contains a detailed analysis of the class of nested canalizing functions over an arbitrary finite field. In addition, the concept of nested canalization is further generalized and closed formulas for the number of such generalized fun...

  16. Morphology of nested fullerenes

    Energy Technology Data Exchange (ETDEWEB)

    Srolovitz, D.J.; Safran, S.A.; Homyonfer, M.; Tenne, R. (Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot 76100 (Israel))

    1995-03-06

    We introduce a continuum model which shows that dislocations and/or grain boundaries are intrinsic features of nested fullerenes whose thickness exceeds a critical value to relieve the large inherent strains in these structures. The ratio of the thickness to the radius of the nested fullerenes is determined by the ratio of the surface to curvature and dislocation (or grain boundary) energies. Confirming experimental evidence is presented for nested fullerenes with small thicknesses and with spherosymmetric shapes.

  17. A Case-Control Study and Meta-Analysis Reveal BDNF Val66Met Is a Possible Risk Factor for PTSD

    Directory of Open Access Journals (Sweden)

    Dagmar Bruenig

    2016-01-01

    Full Text Available Posttraumatic stress disorder (PTSD is a debilitating condition that develops in some people after exposure to a traumatic event. Brain-derived neurotrophic factor (BDNF is highly expressed in the mammalian brain and is thought to be involved in learning and memory processes. A nonsynonymous polymorphism in the BDNF gene, rs6265 (Val66Met, has been hypothesised to be associated with PTSD. Association studies examining the Val66Met polymorphism and PTSD have been inconclusive, likely due to the variability in type of trauma exposure analysed. Vietnam veterans (n=257 screened for PTSD and controlled for trauma exposure were genotyped for BDNF Val66Met. The association was not significant so we incorporated our data into a meta-analysis to obtain greater statistical power. A comprehensive search of more than 1237 articles revealed eight additional studies suitable for meta-analysis (n=3625. A random-effects meta-analysis observed a potential protective factor of the Val/Val genotype. After removing two studies with violation of Hardy-Weinberg equilibrium, findings for the Val/Val genotype reached significance. Subgroup analyses confirmed a trend for this finding. Limitations of some studies that inform this meta-analysis include poorly screened controls and a lack of examination of population stratification. Effectively designed studies should inform this line of research in the future.

  18. Is chronic toxoplasmosis a risk factor for diabetes mellitus? A systematic review and meta-analysis of case-control studies

    Directory of Open Access Journals (Sweden)

    Hamidreza Majidiani

    Full Text Available ABSTRACT Introduction: The global protozoan parasite, Toxoplasma gondii, infects many warm-blooded animals and humans by employing different transmission routes. There have been some recent studies on the probable relevance of infectious agents and diabetes. Therefore, we conducted a systematic review and meta-analysis to identify the possible association between chronic toxoplasmosis and diabetes mellitus. Methods: This study was conducted following the general methodology recommended for systematic reviews and meta-analysis. Nine English literature databases (Google scholar, PubMed, Scopus, Web of science, Science Direct, Ovid, ProQuest, IngentaConnect, and Wiley Online Library were searched, up to January 2016. Random effects model was used to determine odds ratios and their 95% confidence intervals. Results: Our review resulted in a total of seven publications meeting the inclusion criteria. Because of significant heterogeneity, we estimated a common OR by a random effects model at 1.10 (95% CI = 0.13-9.57 with p = 0.929 and 2.39 (95% CI = 1.20-4.75 with p = 0.013 for type 1 and type 2 diabetes mellitus, respectively. Conclusion: Despite the limitations such as low number of studies, this meta-analysis suggests chronic toxoplasmosis as a possible risk factor for type 2 DM. However, based on random effects model no statistically significant association was observed between T. gondii and type 1 DM. It is highly recommended for researchers to carry out more accurate studies aiming to better understand this association.

  19. CYP1A2 rs762551 polymorphism contributes to cancer susceptibility: a meta-analysis from 19 case-control studies

    Directory of Open Access Journals (Sweden)

    Wang Hongge

    2012-11-01

    Full Text Available Abstract Background Genetic polymorphism (rs762551A>C in gene encoding cytochrome P450 1A2 (CYP1A2 has been shown to influence the inducibility of CYP1A2 expression and thus might be associated with risk of several types of human cancer. However, the results of previous studies on the associations of this polymorphism with risk of cancer are not all consistent. To clarify the potential contribution of CYP1A2 rs762551 to cancer risk, we performed a meta-analysis of the published case–control studies. Methods We used PubMed, Embase, OVID, ScienceDirect, and Chinese National Knowledge Infrastructure databases to identify the related publications for this meta-analysis. The pooled odds ratio (OR and 95% confidence interval (CI were calculated using random effect model to evaluate the association of rs762551 with cancer risk. A χ2-based Q-test was used to examine the heterogeneity assumption and the funnel plot and Egger’s test were used to examine the potential publication bias. The leave-one-out sensitivity analysis was conducted to determine whether our assumptions or decisions have a major effect on the results of the review. Results Our analysis of 19 eligible case–control studies showed a significant association between rs762551C variant with risk of cancer in the genetic model of CC versus AA (OR = 1.30, 95% CI = 1.02-1.64 and the dominant model (OR = 1.19, 95% CI = 1.04-1.36. In subgroup analysis based on ethnicity, the rs762551CC genotype was associated with increased cancer risk (OR = 1.29, 95% CI = 1.27-1.63 in co-dominate model and OR = 1.17, 95% CI = 1.02-1.34 in dominant model in Caucasians, but not in Asians and the mixed population. Conclusion These results suggested that CYP1A2 rs762551 polymorphism is likely to be associated with susceptibility to cancer in Caucasians.

  20. A fully-automated software pipeline for integrating breast density and parenchymal texture analysis for digital mammograms: parameter optimization in a case-control breast cancer risk assessment study

    Science.gov (United States)

    Zheng, Yuanjie; Wang, Yan; Keller, Brad M.; Conant, Emily; Gee, James C.; Kontos, Despina

    2013-02-01

    Estimating a woman's risk of breast cancer is becoming increasingly important in clinical practice. Mammographic density, estimated as the percent of dense (PD) tissue area within the breast, has been shown to be a strong risk factor. Studies also support a relationship between mammographic texture and breast cancer risk. We have developed a fullyautomated software pipeline for computerized analysis of digital mammography parenchymal patterns by quantitatively measuring both breast density and texture properties. Our pipeline combines advanced computer algorithms of pattern recognition, computer vision, and machine learning and offers a standardized tool for breast cancer risk assessment studies. Different from many existing methods performing parenchymal texture analysis within specific breast subregions, our pipeline extracts texture descriptors for points on a spatial regular lattice and from a surrounding window of each lattice point, to characterize the local mammographic appearance throughout the whole breast. To demonstrate the utility of our pipeline, and optimize its parameters, we perform a case-control study by retrospectively analyzing a total of 472 digital mammography studies. Specifically, we investigate the window size, which is a lattice related parameter, and compare the performance of texture features to that of breast PD in classifying case-control status. Our results suggest that different window sizes may be optimal for raw (12.7mm2) versus vendor post-processed images (6.3mm2). We also show that the combination of PD and texture features outperforms PD alone. The improvement is significant (p=0.03) when raw images and window size of 12.7mm2 are used, having an ROC AUC of 0.66. The combination of PD and our texture features computed from post-processed images with a window size of 6.3 mm2 achieves an ROC AUC of 0.75.

  1. CERAMIC: Case-Control Association Testing in Samples with Related Individuals, Based on Retrospective Mixed Model Analysis with Adjustment for Covariates.

    Directory of Open Access Journals (Sweden)

    Sheng Zhong

    2016-10-01

    Full Text Available We consider the problem of genetic association testing of a binary trait in a sample that contains related individuals, where we adjust for relevant covariates and allow for missing data. We propose CERAMIC, an estimating equation approach that can be viewed as a hybrid of logistic regression and linear mixed-effects model (LMM approaches. CERAMIC extends the recently proposed CARAT method to allow samples with related individuals and to incorporate partially missing data. In simulations, we show that CERAMIC outperforms existing LMM and generalized LMM approaches, maintaining high power and correct type 1 error across a wider range of scenarios. CERAMIC results in a particularly large power increase over existing methods when the sample includes related individuals with some missing data (e.g., when some individuals with phenotype and covariate information have missing genotype, because CERAMIC is able to make use of the relationship information to incorporate partially missing data in the analysis while correcting for dependence. Because CERAMIC is based on a retrospective analysis, it is robust to misspecification of the phenotype model, resulting in better control of type 1 error and higher power than that of prospective methods, such as GMMAT, when the phenotype model is misspecified. CERAMIC is computationally efficient for genomewide analysis in samples of related individuals of almost any configuration, including small families, unrelated individuals and even large, complex pedigrees. We apply CERAMIC to data on type 2 diabetes (T2D from the Framingham Heart Study. In a genome scan, 9 of the 10 smallest CERAMIC p-values occur in or near either known T2D susceptibility loci or plausible candidates, verifying that CERAMIC is able to home in on the important loci in a genome scan.

  2. Sulfotransferase SULT1A1 Arg213His polymorphism with cancer risk: a meta-analysis of 53 case-control studies.

    Directory of Open Access Journals (Sweden)

    Juanjuan Xiao

    Full Text Available BACKGROUND: The SULT1A1 Arg213His (rs9282861 polymorphism is reported to be associated with many kinds of cancer risk. However, the findings are conflicting. For better understanding this SNP site and cancer risk, we summarized available data and performed this meta-analysis. METHODS: Data were collected from the following electronic databases: PubMed, Web of Knowledge and CNKI. The association was assessed by odd ratio (OR and the corresponding 95% confidence interval (95% CI. RESULTS: A total of 53 studies including 16733 cancer patients and 23334 controls based on the search criteria were analyzed. Overall, we found SULT1A1 Arg213His polymorphism can increase cancer risk under heterozygous (OR  1.09, 95% CI = 1.01-1.18, P = 0.040, dominant (OR = 1.10, 95% CI = 1.01-1.19, P = 0.021 and allelic (OR = 1.08, 95% CI = 1.02-1.16, P = 0.015 models. In subgroup analyses, significant associations were observed in upper aero digestive tract (UADT cancer (heterozygous model: OR = 1.62, 95% CI = 1.11-2.35, P = 0.012; dominant model: OR = 1.63, 95% CI = 1.13-2.35, P = 0.009; allelic model: OR = 1.52, 95% CI = 1.10-2.11, P = 0.012 and Indians (recessive model: OR = 1.93, 95% CI = 1.22-3.07, P = 0.005 subgroups. Hospital based study also showed marginally significant association. In the breast cancer subgroup, ethnicity and publication year revealed by meta-regression analysis and one study found by sensitivity analysis were the main sources of heterogeneity. The association between SULT1A1 Arg213His and breast cancer risk was not significant. No publication bias was detected. CONCLUSIONS: The present meta-analysis suggests that SULT1A1 Arg213His polymorphism plays an important role in carcinogenesis, which may be a genetic factor affecting individual susceptibility to UADT cancer. SULT1A1 Arg213His didn't show any association with breast cancer, but the possible risk in Asian population needs further investigation.

  3. Meta-analysis of the association between COX-2 polymorphisms and risk of colorectal cancer based on case-control studies.

    Directory of Open Access Journals (Sweden)

    Qiliu Peng

    Full Text Available OBJECTIVE: Cyclooxygenase-2 (COX-2 is an inducible enzyme converting arachidonic acid to prostaglandins and playing important roles in inflammatory diseases as well as tumor development. Previous studies investigating the association between COX-2 polymorphisms and colorectal cancer (CRC risk reported conflicting results. We performed a meta-analysis of all available studies to explore this association. METHODS: All studies published up to October 2013 on the association between COX-2 polymorphisms and CRC risk were identified by searching electronic databases PubMed, EMBASE, and Cochrane library. The association between COX-2 polymorphisms and CRC risk was assessed by odds ratios (ORs together with their 95% confidence intervals (CIs. RESULTS: Ten studies with 6,774 cases and 9,772 controls were included for -1195A>G polymorphism, 13 studies including 6,807 cases and 10,052 controls were available for -765G>C polymorphism, and 8 studies containing 5,121 cases and 7,487 controls were included for 8473T>C polymorphism. With respect to -765G>C polymorphism, we did not find a significant association with CRC risk when all eligible studies were pooled into the meta-analysis. However, in subgroup analyses by ethnicity and cancer location, with a Bonferroni corrected alpha of 0.05/2, statistical significant increased CRC risk was found in the Asian populations (dominant model CC+CG vs. GG: OR = 1.399, 95%CI: 1.113-1.760, P = 0.004 and rectum cancer patients (CC vs. GG: OR = 2.270, 95%CI: 1.295-3.980, P = 0.004; Recessive model CC vs. CG+GG: OR = 2.269, 95%CI: 1.297-3.970, P = 0.004. In subgroup analysis according to source of control, no significant association was detected. With respect to -1195A>G and 8473T>C polymorphisms, no significant association with CRC risk was demonstrated in the overall and subgroup analyses. CONCLUSIONS: The present meta-analysis suggests that the COX-2 -765G>C polymorphism may be a risk factor for

  4. The Effect of Chronic Bacterial Prostatitis on Semen Quality in Adult Men: A Meta-Analysis of Case-control Studies

    Science.gov (United States)

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

    2014-01-01

    Chronic bacterial prostatitis (CBP) is caused by bacterial infection and maintains a condition of lower urinary tract infection. It may be a cause of male infertility. However, studies showed inconsistent results regarding the effect of CBP on several parameters of semen. Hence, we conducted a meta-analysis to examine the effect of CBP on basic semen parameters. A systematic review was conducted with Medline, PubMed, EMBASE, and two Chinese databases (CNKI and WANG FANG) to identify relevant studies that involved the effect of CBP on semen parameters up to July 2014. Both RevMan5.2 and STATA 12.0 software were used for the statistical analysis. Based on the inclusion and exclusion criteria, seven studies were included. The study illustrated that sperm vitality, sperm total motility, and the percentage of progressively motile sperm from CBP patients were significantly lower than controls (SMD(95%CI) −0.81[−1.14, −0.47], −1.00[−1.28, −0.73], −0.41 [−0.70, −0.12], P<0.05, respectively). However, CBP had no significant effect on semen volume, sperm concentration and the duration of semen liquefaction. In summary, our study revealed that there was a significant negative effect of CBP on sperm vitality, sperm total motility, and the percentage of progressively motile sperm. Additional, studies with larger number of subjects are needed. PMID:25429735

  5. Association of CDKN2B-AS1 rs1333049 with Brain Diseases: A Case-control Study and a Meta-analysis

    Science.gov (United States)

    Zhao, Jikuang; Wu, Xizheng; Nie, Sheng; Gao, Xiang; Sun, Jie; Li, Keqin; Zhang, Tiefeng; Huang, Yi

    2017-01-01

    Objective CDKN2B-AS1 polymorphisms were shown to associate with the risk of stroke in European. The goal of this study was to evaluate the contribution of CDKN2B-AS1 rs1333049 to the risk of hemorrhagic stroke (HS) and brain tumor (BT) in Han Chinese. Methods A total of 142 HSs, 115 BTs, and 494 controls were included in the current association study. The genotyping test was performed using the melting temperature shift method. Results We failed to validate the association of CDKN2B-AS1 rs1333049 with the risk of brain disease. Significantly higher levels of low-density lipoprotein cholesterol (LDL-C) (p=0.027), high-density lipoprotein cholesterol (HDL-C) (p0.05). The meta-analysis of 10 studies among 133,993 individuals concluded that rs1333049 of CDKN2B-AS1 gene was likely to increase a 16% incidence rate of cerebrovascular disease (CD) among various populations (odds ratio 1.16, 95% confidence interval 1.08–1.25; pLDL-C, HDL-C and TC in the HS patients. Meta-analysis supported the association between rs1333049 and CD risk in various populations, although we were unable to observe association between rs1333049 and the risk of HSs in Han Chinese. PMID:28138111

  6. Association between XRCC1 and XRCC3 polymorphisms with lung cancer risk: a meta-analysis from case-control studies.

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    Guohua Huang

    Full Text Available Many studies have reported the association of X-ray repair cross-complementing group 1 (XRCC1 Arg399Gln, Arg194Trp, Arg280His, -77T>C, and X-ray repair cross-complementing group 3 (XRCC3 T241M polymorphisms with lung cancer risk, but the results remained controversial. Hence, we performed a meta-analysis to investigate the association between lung cancer risk and XRCC1 Arg399Gln (14,156 cases and 16,667 controls from 41 studies, Arg194Trp (7,426 cases and 9,603 controls from 23 studies, Arg280His (6,211 cases and 6,763 controls from 16 studies, -77T>C (2,487 cases and 2,576 controls from 5 studies, and XRCC3 T241M (8,560 cases and 11,557 controls from 19 studies in different inheritance models. We found that -77T>C polymorphism was associated with increased lung cancer risk (dominant model: odds ration [OR] = 1.45, 95% confidence interval [CI] = 1.27-1.66, recessive model: OR = 1.73, 95% CI = 1.14-2.62, additive model: OR = 1.91, 95% CI = 1.24-1.94 when all the eligible studies were pooled into the meta-analysis. In the stratified and sensitive analyses, significantly decreased lung cancer risk was observed in overall analysis (dominant model: OR = 0.83, 95% CI = 0.78-0.89; recessive model: OR = 0.90, 95% CI = 0.81-1.00; additive model: OR = 0.82, 95% CI = 0.74-0.92, Caucasians (dominant model: OR = 0.82, 95% CI = 0.76-0.87; recessive model: OR = 0.89, 95% CI = 0.80-0.99; additive model: OR = 0.81, 95% CI = 0.73-0.91, and hospital-based controls (dominant model: OR = 0.81, 95% CI = 0.76-0.88; recessive model: OR = 0.89, 95% CI = 0.79-1.00; additive model: OR = 0.80, 95% CI = 0.71-0.90 for XRCC3 T241M. In conclusion, this meta-analysis indicates that XRCC1 -77T>C shows an increased lung cancer risk and XRCC3 T241M polymorphism is associated with decreased lung cancer risk, especially in Caucasians.

  7. Association of CDKN2BAS Polymorphism rs4977574 with Coronary Heart Disease: A Case-Control Study and a Meta-Analysis

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    Yi Huang

    2014-09-01

    Full Text Available The goal of our study was to explore the significant association between a non-protein coding single nucleotide polymorphism (SNP rs4977574 of CDKN2BAS gene and coronary heart disease (CHD. A total of 590 CHD cases and 482 non-CHD controls were involved in the present association study. A strong association of rs4977574 with CHD was observed in females (genotype: p = 0.002; allele: p = 0.002, odd ratio (OR = 1.57, 95% confidential interval (CI = 1.18–2.08. Moreover, rs4977574 was more likely to be a risk variant of CHD under the recessive model in females (χ2 = 10.29, p = 0.003, OR = 2.14, 95% CI = 1.31–2.77. A breakdown analysis by age had shown that there was an 87% increased risk of CHD for females younger than 65 years (genotype: χ2 = 14.64, degrees of freedom (df = 2, p = 0.0002; allele: χ2 = 11.31, df = 1, p = 0.0008, OR = 1.87, 95% CI = 1.30–2.70. Similar observation was also found in males younger than 65 years (genotype: χ2 = 8.63, df = 2, p = 0.04; allele: χ2 = 7.55, df = 1, p = 0.006, OR = 1.45, 95% CI = 1.11–1.90. p values were adjusted by age, sex, smoking, high density lipoprotein cholesterol (HDL-C and low density lipoprotein cholesterol (LDL-C. Meta-analysis of 23 studies among 36,452 cases and 39,781 controls showed a strong association between rs4977574 and the risk of CHD (p < 0.0001, OR = 1.27, 95% CI = 1.22–1.31.

  8. Magnetic resonance imaging contribution for diagnosing symptomatic neurovascular contact in classical trigeminal neuralgia: a blinded case-control study and meta-analysis.

    Science.gov (United States)

    Antonini, Giovanni; Di Pasquale, Antonella; Cruccu, Giorgio; Truini, Andrea; Morino, Stefania; Saltelli, Giorgia; Romano, Andrea; Trasimeni, Guido; Vanacore, Nicola; Bozzao, Alessandro

    2014-08-01

    Although classical trigeminal neuralgia (CTN) is frequently caused by neurovascular contact (NVC) at the trigeminal root entry zone (REZ), both anatomical and MRI studies have shown that NVC of the trigeminal nerve frequently occurs in individuals without CTN. To assess the accuracy of MRI in distinguishing symptomatic from asymptomatic trigeminal NVC, we submitted to high-definition MRI the series of CTN patients referred to our outpatient service between June 2011 and January 2013 (n=24), and a similar number of age-matched healthy controls. Two neuroradiologists, blinded to the clinical data, evaluated whether the trigeminal nerve displayed NVC in the REZ or non-REZ, whether it was dislocated by the vessel or displayed atrophy at the contact site, and whether the offending vessel was an artery or a vein. Our data were meta-analyzed with those of all similar studies published from January 1970 to June 2013. In our sample, REZ contact, nerve dislocation and nerve atrophy were independently associated with CTN (P=.027; P=.005; P=.035 respectively). Compared to a rather low sensitivity of each of these items (alone or in combination), their specificity was high. When REZ contact and nerve atrophy coexisted, both specificity and positive predictive value rose to 100%. Meta-analysis showed that REZ NVC was detected in 76% of symptomatic and 17% of asymptomatic nerves (PNVC, as detected by MRI, is highly likely to be symptomatic when it is associated with anatomical nerve changes.

  9. Construction patterns of birds’ nests provide insight into nest-building behaviours

    Science.gov (United States)

    Goodman, Adrian M.

    2017-01-01

    Previous studies have suggested that birds and mammals select materials needed for nest building based on their thermal or structural properties, although the amounts or properties of the materials used have been recorded for only a very small number of species. Some of the behaviours underlying the construction of nests can be indirectly determined by careful deconstruction of the structure and measurement of the biomechanical properties of the materials used. Here we examined this idea in an investigation of Bullfinch (Pyrrhula pyrrhula) nests as a model for open-nesting songbird species that construct a “twig” nest, and tested the hypothesis that materials in different parts of nests serve different functions. The quantities of materials present in the nest base, sides and cup were recorded before structural analysis. Structural analysis showed that the base of the outer nests were composed of significantly thicker, stronger and more rigid materials compared to the side walls, which in turn were significantly thicker, stronger and more rigid than materials used in the cup. These results suggest that the placement of particular materials in nests may not be random, but further work is required to determine if the final structure of a nest accurately reflects the construction process. PMID:28265501

  10. Construction patterns of birds’ nests provide insight into nest-building behaviours

    Directory of Open Access Journals (Sweden)

    Lucia Biddle

    2017-02-01

    Full Text Available Previous studies have suggested that birds and mammals select materials needed for nest building based on their thermal or structural properties, although the amounts or properties of the materials used have been recorded for only a very small number of species. Some of the behaviours underlying the construction of nests can be indirectly determined by careful deconstruction of the structure and measurement of the biomechanical properties of the materials used. Here we examined this idea in an investigation of Bullfinch (Pyrrhula pyrrhula nests as a model for open-nesting songbird species that construct a “twig” nest, and tested the hypothesis that materials in different parts of nests serve different functions. The quantities of materials present in the nest base, sides and cup were recorded before structural analysis. Structural analysis showed that the base of the outer nests were composed of significantly thicker, stronger and more rigid materials compared to the side walls, which in turn were significantly thicker, stronger and more rigid than materials used in the cup. These results suggest that the placement of particular materials in nests may not be random, but further work is required to determine if the final structure of a nest accurately reflects the construction process.

  11. Autonomic dysfunction in mild cognitive impairment: evidence from power spectral analysis of heart rate variability in a cross-sectional case-control study.

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    Paola Nicolini

    Full Text Available Mild cognitive impairment (MCI is set to become a major health problem with the exponential ageing of the world's population. The association between MCI and autonomic dysfunction, supported by indirect evidence and rich with clinical implications in terms of progression to dementia and increased risk of mortality and falls, has never been specifically demonstrated.To conduct a comprehensive assessment of autonomic function in subjects with MCI by means of power spectral analysis (PSA of heart rate variability (HRV at rest and during provocative manoeuvres.This cross-sectional study involved 80 older outpatients (aged ≥ 65 consecutively referred to a geriatric unit and diagnosed with MCI or normal cognition (controls based on neuropsychological testing. PSA was performed on 5-minute electrocardiographic recordings under three conditions--supine rest with free breathing (baseline, supine rest with paced breathing at 12 breaths/minute (parasympathetic stimulation, and active standing (orthosympathetic stimulation--with particular focus on the changes from baseline to stimulation of indices of sympathovagal balance: normalized low frequency (LFn and high frequency (HFn powers and the LF/HF ratio. Blood pressure (BP was measured at baseline and during standing. Given its exploratory nature in a clinical population the study included subjects on medications with a potential to affect HRV.There were no significant differences in HRV indices between the two groups at baseline. MCI subjects exhibited smaller physiological changes in all three HRV indices during active standing, consistently with a dysfunction of the orthosympathetic system. Systolic BP after 10 minutes of standing was lower in MCI subjects, suggesting dysautonomia-related orthostatic BP dysregulation.Our study is novel in providing evidence of autonomic dysfunction in MCI. This is associated with orthostatic BP dysregulation and the ongoing follow-up of the study population will

  12. Cigarette smoking and lung cancer--relative risk estimates for the major histological types from a pooled analysis of case-control studies.

    Science.gov (United States)

    Pesch, Beate; Kendzia, Benjamin; Gustavsson, Per; Jöckel, Karl-Heinz; Johnen, Georg; Pohlabeln, Hermann; Olsson, Ann; Ahrens, Wolfgang; Gross, Isabelle Mercedes; Brüske, Irene; Wichmann, Heinz-Erich; Merletti, Franco; Richiardi, Lorenzo; Simonato, Lorenzo; Fortes, Cristina; Siemiatycki, Jack; Parent, Marie-Elise; Consonni, Dario; Landi, Maria Teresa; Caporaso, Neil; Zaridze, David; Cassidy, Adrian; Szeszenia-Dabrowska, Neonila; Rudnai, Peter; Lissowska, Jolanta; Stücker, Isabelle; Fabianova, Eleonora; Dumitru, Rodica Stanescu; Bencko, Vladimir; Foretova, Lenka; Janout, Vladimir; Rudin, Charles M; Brennan, Paul; Boffetta, Paolo; Straif, Kurt; Brüning, Thomas

    2012-09-01

    Lung cancer is mainly caused by smoking, but the quantitative relations between smoking and histologic subtypes of lung cancer remain inconclusive. By using one of the largest lung cancer datasets ever assembled, we explored the impact of smoking on risks of the major cell types of lung cancer. This pooled analysis included 13,169 cases and 16,010 controls from Europe and Canada. Studies with population controls comprised 66.5% of the subjects. Adenocarcinoma (AdCa) was the most prevalent subtype in never smokers and in women. Squamous cell carcinoma (SqCC) predominated in male smokers. Age-adjusted odds ratios (ORs) were estimated with logistic regression. ORs were elevated for all metrics of exposure to cigarette smoke and were higher for SqCC and small cell lung cancer (SCLC) than for AdCa. Current male smokers with an average daily dose of >30 cigarettes had ORs of 103.5 (95% confidence interval (CI): 74.8-143.2) for SqCC, 111.3 (95% CI: 69.8-177.5) for SCLC and 21.9 (95% CI: 16.6-29.0) for AdCa. In women, the corresponding ORs were 62.7 (95% CI: 31.5-124.6), 108.6 (95% CI: 50.7-232.8) and 16.8 (95% CI: 9.2-30.6), respectively. Although ORs started to decline soon after quitting, they did not fully return to the baseline risk of never smokers even 35 years after cessation. The major result that smoking exerted a steeper risk gradient on SqCC and SCLC than on AdCa is in line with previous population data and biological understanding of lung cancer development.

  13. Association of sulfotransferase SULT1A1 with breast cancer risk: a meta-analysis of case-control studies with subgroups of ethnic and menopausal statue

    Directory of Open Access Journals (Sweden)

    Shao Zhimin

    2010-07-01

    Full Text Available Abstract Background Sulfotransferase (SULT plays an important role in the formation of estrogen which is usually conferred as a risk factor for breast cancer. Polymorphism of the SULT1A1 may be closely associated with breast cancer. However, studies on the association between polymorphism and breast cancer have yielded inconsistent results. We performed a meta-analysis including ethnic subgroup and menopausal statue subgroup to investigate the association of SULT1A1 Arg213His polymorphism with breast cancer. Methods PubMed, EBSCO and Web of Science databases were searched for the correlative articles up to January 2010 (10362 breast cancer patients and 14250 controls. The risk (odds ratio, OR was used to estimate the association between SULT1A1 polymorphism and breast cancer risk. All of the data from each study use either fixed-effects or random-effects. Results We found that SULT1A1 Arg213His had no exact effect to increase the risk of breast cancer (OR = 1.07, 95% CI: 0.97-1.17, P = 0.164, but it did increase the risk of breast cancer among postmenopausal women in the dominant model (OR = 1.28, 95%CI: 1.04-1.58, P = 0.019. No similar effect was found among premenopausal breast cancer women (OR = 1.06, 95%CI: 0.88-1.27, P = 0.537. There was a significant increase in breast cancer risk among Asian women (OR = 2.03, 95% CI: 1.00-4.14, P = 0.051 but not Caucasian women in recessive model. There was publication bias among postmenopausal women subgroup (P = 0.002, however by using the trim and fill method, if the publication bias was the only source of the funnel plot asymmetry, it needed two more studies to be symmetrical. The value of Log OR did not change too much after the adjustment and the fail-safe number of missing studies that would bring the P-value changed was 17. Conclusions We concluded that the polymorphism of SULT1A1 Arg213His might be one of the high risk factors for breast cancer in Asian women and in postmenopausal women for all

  14. Spatial analysis of toxic emissions in LCA: a sub-continental nested USEtox model with freshwater archetypes.

    Science.gov (United States)

    Kounina, Anna; Margni, Manuele; Shaked, Shanna; Bulle, Cécile; Jolliet, Olivier

    2014-08-01

    This paper develops continent-specific factors for the USEtox model and analyses the accuracy of different model architectures, spatial scales and archetypes in evaluating toxic impacts, with a focus on freshwater pathways. Inter-continental variation is analysed by comparing chemical fate and intake fractions between sub-continental zones of two life cycle impact assessment models: (1) the nested USEtox model parameterized with sub-continental zones and (2) the spatially differentiated IMPACTWorld model with 17 interconnected sub-continental regions. Substance residence time in water varies by up to two orders of magnitude among the 17 zones assessed with IMPACTWorld and USEtox, and intake fraction varies by up to three orders of magnitude. Despite this variation, the nested USEtox model succeeds in mimicking the results of the spatially differentiated model, with the exception of very persistent volatile pollutants that can be transported to polar regions. Intra-continental variation is analysed by comparing fate and intake fractions modelled with the a-spatial (one box) IMPACT Europe continental model vs. the spatially differentiated version of the same model. Results show that the one box model might overestimate chemical fate and characterisation factors for freshwater eco-toxicity of persistent pollutants by up to three orders of magnitude for point source emissions. Subdividing Europe into three archetypes, based on freshwater residence time (how long it takes water to reach the sea), improves the prediction of fate and intake fractions for point source emissions, bringing them within a factor five compared to the spatial model. We demonstrated that a sub-continental nested model such as USEtox, with continent-specific parameterization complemented with freshwater archetypes, can thus represent inter- and intra-continental spatial variations, whilst minimizing model complexity.

  15. Automated Forensic Animal Family Identification by Nested PCR and Melt Curve Analysis on an Off-the-Shelf Thermocycler Augmented with a Centrifugal Microfluidic Disk Segment.

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    Mark Keller

    Full Text Available Nested PCR remains a labor-intensive and error-prone biomolecular analysis. Laboratory workflow automation by precise control of minute liquid volumes in centrifugal microfluidic Lab-on-a-Chip systems holds great potential for such applications. However, the majority of these systems require costly custom-made processing devices. Our idea is to augment a standard laboratory device, here a centrifugal real-time PCR thermocycler, with inbuilt liquid handling capabilities for automation. We have developed a microfluidic disk segment enabling an automated nested real-time PCR assay for identification of common European animal groups adapted to forensic standards. For the first time we utilize a novel combination of fluidic elements, including pre-storage of reagents, to automate the assay at constant rotational frequency of an off-the-shelf thermocycler. It provides a universal duplex pre-amplification of short fragments of the mitochondrial 12S rRNA and cytochrome b genes, animal-group-specific main-amplifications, and melting curve analysis for differentiation. The system was characterized with respect to assay sensitivity, specificity, risk of cross-contamination, and detection of minor components in mixtures. 92.2% of the performed tests were recognized as fluidically failure-free sample handling and used for evaluation. Altogether, augmentation of the standard real-time thermocycler with a self-contained centrifugal microfluidic disk segment resulted in an accelerated and automated analysis reducing hands-on time, and circumventing the risk of contamination associated with regular nested PCR protocols.

  16. 利用光谱分析技术探测红火蚁蚁巢%Detection of Solenopsis invicta nest using spectrum analysis technology

    Institute of Scientific and Technical Information of China (English)

    吴伟斌; 支磊; 洪添胜; 许益镌; 曾玲; 黄双萍; 邓小玲

    2013-01-01

    . Research on the detection method of a Solenopsis invicta nest to eliminate Solenopsis invicta from the source is of practical significance to the prevention of a Solenopsis invicta disaster. Therefore, finding out the location of a nest of Solenopsis invicta is of more practical value than only exterminating Solenopsis invicta. The feasibility of detection of a nest of Solenopsis invicta based on spectrum analysis technology was examined by using an optical spectrum instrument with reflect characteristics. A differential coefficient method and a logarithmic method to analyze original spectral reflectivity were used. The method of using character factors was studied to get the best waveband for distinguishing the ant nest from other things. An Eculidean distance method was used to calculate the average distance, and effective band of the nest of Solenopsis invicta’s recognized effect. In addition, the average of the Euclidean distance of different features is greater than the average of the Euclidean distance of the same feature, and the samples, which were collected and measured by the laboratory hyper-spectral imager to verify the reliability of the selected band. Finally, the results were compared with the traditional method. We randomly selected eight sample points in the Wushan Square of South China Agricultural University. Using the traditional method and a spectrum analytical method to prove it, we got the same result. However, it is more convenient and faster to get the information by using the spectrum analytical method. As a result, the effective wavebands to recognize the Solenopsis invicta nest mostly concentrate on 701-1 510 nm, which are mainly red light bands and near-infrared bands. Additionally, the observation shows that the original spectrum and the logarithmic method could be used to distinguish the nest of Solenopsis invicta from common soil and grass. Moreover, the latter can make it clearer than the others, while the spectrum first

  17. Frog Foam Nest Protein Diversity and Synthesis.

    Science.gov (United States)

    Hissa, Denise Cavalcante; Bezerra, Walderly Melgaço; Freitas, Cléverson Diniz Teixeira De; Ramos, Márcio Viana; Lopes, José Luiz De Souza; Beltramini, Leila Maria; Roberto, Igor Joventino; Cascon, Paulo; Melo, Vânia Maria Maciel

    2016-08-01

    Some amphibian species have developed a breeding strategy in which they deposit their eggs in stable foam nests to protect their eggs and larvae. The frog foam nests are rich in proteins (ranaspumin), especially surfactant proteins, involved in the production of the foam nest. Despite the ecological importance of the foam nests for evolution and species conservation, the biochemical composition, the long-term stability and even the origin of the components are still not completely understood. Recently we showed that Lv-RSN-1, a 23.5-kDa surfactant protein isolated from the nest of the frog Leptodacylus vastus, presents a structural conformation distinct from any protein structures yet reported. So, in the current study we aimed to reveal the protein composition of the foam nest of L. vastus and further characterize the Lv-RSN-1. Proteomic analysis showed the foam nest contains more than 100 of proteins, and that Lv-RSN-1 comprises 45% of the total proteins, suggesting a key role in the nest construction and stability. We demonstrated by Western blotting that Lv-RSN-1 is mainly produced only by the female in the pars convoluta dilata, which highlights the importance of the female preservation for conservation of species that depend on the production of foam nests in the early stages of development. Overall, our results showed the foam nest of L. vastus is composed of a great diversity of proteins and that besides Lv-RSN-1, the main protein in the foam, other proteins must have a coadjuvant role in building and stability of the nest.

  18. [Analysis of different methods of extracting DNA from paraffin-embedded tissues and the application of nest PCR].

    Science.gov (United States)

    Yan, Limin; Sun, Baocun; Zhao, Xiulan; Liu, Zenghui; Song, Wenjing

    2011-08-01

    The aim of this research was to explore the most optimal method of DNA extraction from formalin-fixed, paraffin-embedded (FFPE) tissues, and to improve the amplification of long fragments with the method. Three methods, one step method, phenol-chloroform extraction method, and genomic DNA purification kit method, were employed to extract DNA from twenty normal thyroid tissues which were fixed with formalin and embedded with paraffin. The highest proportionality of OD260/OD280 in the examples was obtained by phenol-chloroform extraction method, 1.703 +/- 0.086, compared to the results of the other two methods. As for the long DNA segments amplification, the achievement ratio of one step method, phenol-chloroform extraction method and genomic DNA purification kit method were 0%, 5% and 10%, respectively, by traditional PCR method, but 0%, 95% and 85% respectively by the nest PCR. We have found that the best process of extracting DNA from FFPE is digesting by proteinase K and purifying by phenol-chloroform, and it is effective to amplify long DNA segments from FFPE by nest PCR.

  19. Association of the COQ2 V393A variant with risk of multiple system atrophy in East Asians: a case-control study and meta-analysis of the literature.

    Science.gov (United States)

    Zhao, QuanZhen; Yang, Xinglong; Tian, SiJia; An, Ran; Zheng, JinHua; Xu, Yanming

    2016-03-01

    Recent studies in Japan have associated multiple system atrophy (MSA), a neurodegenerative disease of uncertain etiology, with polymorphism in the COQ2 gene. This led us to explore whether the same polymorphism is associated with MSA in Han Chinese and more broadly in East Asians. We conducted a case-control study with 82 Han Chinese with probable MSA and 484 gender- and age-matched healthy subjects, genotyping them using the ligase detection reaction. The results were meta-analyzed together with data from four previous studies to gain a broader picture of possible disease associations in East Asian populations. The COQ2 variants M78V and R337X were not detected in our Han Chinese patients or controls; only the heterozygous V393A variant (CT genotype) was detected. The frequency of this genotype was significantly higher in patients (7.3%) than in controls (1.86%; OR 4.17, 95% CI 1.44-12.04, p = 0.004). Subgroup analysis among patients showed a significant association of V393A with MSA involving cerebellar signs (MSA-C; OR 4.59, 95% CI 1.36-15.48, p = 0.007), but not with MSA involving parkinsonism (MSA-P). Meta-analysis of our results in Han Chinese with data from case-control studies in Japan, Korea, mainland China and Taiwan showed a significant association of V393A with MSA (OR 2.05, 95% CI 1.29-3.25, p = 0.002), which subgroup analysis showed to be significant for MSA-C (OR 2.75, 95% CI 1.98-3.84, p < 0.001) but not for MSA-P (OR 1.25, 95% CI 0.64-2.46, p = 0.51). These findings provide evidence that the previously reported association of COQ2 V393A polymorphism with increased risk of MSA in Japanese also applies to Han Chinese, as well as more broadly to other East Asian populations. This association may be particularly strong for MSA-C.

  20. The SNP rs961253 in 20p12.3 is associated with colorectal cancer risk: a case-control study and a meta-analysis of the published literature.

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    Xiawen Zheng

    Full Text Available BACKGROUND: Colorectal cancer (CRC is the third common cancer and the fourth leading cause of cancer death worldwide. A single nucleotide polymorphism (SNP, rs961253 located in 20p12, was firstly described to be associated with the increased risk of CRC in a genome-wide association study; however, more recent replication studies yielded controversial results. METHODOLOGY/PRINCIPAL FINDINGS: A hospital-based case-control study in a Chinese population was firstly performed, and then a meta-analysis combining the current and previously published studies were conducted to explore the real effect of rs961253 in CRC susceptibility. In the Chinese population including 641 cases and 1037 controls, per-A-allele conferred an OR of 1.60 (95% CI = 1.26-2.02 under additive model. In the meta-analysis including 29859 cases and 29696 controls, per-A-allele have an OR of 1.13 (95% CI = 1.09-1.18 under a random-effects model due to heterogeneity (P = 0.019. Nevertheless, the heterogeneity can be totally explained by ethnicity, with the tau(2 reduced to 0 after including ethnicity in meta-regression model. In stratified analysis by ethnicity, per-A-allele had ORs of 1.34 (95% CI = 1.20-1.50 and 1.11 (95% CI = 1.08-1.14 for Asian and European, respectively, without heterogeneity. Modest influence of each study was observed on overall estimate in sensitive analysis, and evident tendency to significant association was seen in cumulative analysis over time, together indicating the robust stability of the current results. CONCLUSIONS/SIGNIFICANCE: The results from our study and the meta-analysis provided firm evidence that rs961253 significantly contributed to CRC risk in both Asian and European population.

  1. Correlation between low development quotient of children and first-trimester serum level of free fatty acids in mothers: a nested case-control study%儿童低发育商与母亲孕早期血清游离脂肪酸关系

    Institute of Scientific and Technical Information of China (English)

    孙蕾; 刘开永; 盛杰; 陶芳标; 郝加虎; 王磊; 蔡传兰

    2013-01-01

    were significant differences in the levels of polyunsaturated fatty acis (PUFA),ω-3PUFA,ω-6PUFA,docosapentaenoic acid (DPA),docosahexaenoic acid (DHA),eicosapentaenoic acid (EPA),EPA + DHA,DHA + anachidonic acid (AA) between the cases and the controls (P < 0.05 for all).High level of EPA served as a protective factor of child low development quotient (odds ratio [OR] =0.37,95 % confidence interval [95 % CI]:0.17-0.79).Correlation analysis demonstrated that there were relationships between EPA and DPA (r =0.608),DHA (r =0.659),AA (r =0.605),and DHA + AA (r =0.676).The level of EPA in maternal serum showed a downward trend with the reduced frequency of fish and other seafood intake (F =3.410,P =0.019).Conclusion The study suggests that there is an association of child's low development quotient with the lack of PUFA supplement of the pregnancy woman.Pregnant women should supplement PUFA to ensure normal mental development of the infant.

  2. 脑肿瘤与手机使用病例对照研究的Meta分析%Brain tumor and mobile phone use: meta-analysis of case-control studies

    Institute of Scientific and Technical Information of China (English)

    常勇; 吴磊; 彭晓武; 宋世震; 梅勇; 叶方立

    2012-01-01

    目的 评价手机使用与脑肿瘤危险性的联系.方法 采用Meta分析方法对2000年至2011年发表的关于脑肿瘤与手机使用相关的病例对照研究文献进行定量分析.结果 13篇病例对照研究文献纳入,规律使用手机者未见脑瘤危险性增高;而长期使用手机10年以上者与脑肿瘤发生存在关联(OR=1.ll,95% CI:1.01~1.22),长期同侧使用手机发生脑肿瘤危险性增加32%(OR=1.32,95% CI:1.14~1.54).结论 规律使用手机并不增高脑肿瘤发生的风险,长期使用手机可能增加脑肿瘤发生的风险,但分析中的偏倚与混杂因子可能影响因果关系的解释.%Objective To evaluate the association between mobile phone use and brain tumor risk. Methods Meta-analysis method was used to analyze the case-control studies on association between brain tumor and mobile phone use, the data were searched from 2000 to 2011. Results A total of 13 case-control studies were included. Analysis findings showed no increase in risk for regular mobile phone user was seen. A somewhat increased risk was found for long-term mobile phone (0R=1.11; 95% CI: 1.01-1.22). There were suggestions of an increased risk of brain tumor for ipsilateral exposures in 10 years or more (OR=1.32; 95% CI: 1.14—1.54). Conclusion Overall, no increase in risk of brain tumor was observed among uses regular using mobile phone. There were suggestions of an increased risk of brain tumor with long-term heavy use of mobile phone, but biases and confounding factors may prevent a causal interpretation.

  3. Early pregnancy sex steroids and maternal breast cancer: a nested case-control study.

    Science.gov (United States)

    Fortner, Renée T; Schock, Helena; Kaaks, Rudolf; Lehtinen, Matti; Pukkala, Eero; Lakso, Hans-Åke; Tanner, Minna; Kallio, Raija; Joensuu, Heikki; Grankvist, Kjell; Zeleniuch-Jacquotte, Anne; Toniolo, Paolo; Lundin, Eva; Surcel, Helja-Marja

    2014-12-01

    Pregnancy, parity, and circulating steroid hormone levels are associated with risk of breast cancer, but little is known about hormone concentrations during pregnancy and subsequent breast cancer risk. We evaluated early pregnancy (pregnancies registered in Finland since 1983. Individuals with samples collected in the first pregnancy leading to a live birth were eligible. Breast cancer cases (n = 1,199) were identified through linkage with the Finnish Cancer Registry; 2,281 matched controls were selected using incidence density sampling. ORs were calculated using conditional logistic regression. Hormone concentrations were not associated with breast cancer overall. Estradiol was positively associated with risk of breast cancer diagnosed age hormones were associated with increased risk of estrogen receptor (ER)- and progesterone receptor (PR)-negative tumors in women age hormones and ER(+)/PR(+) disease. These data suggest a positive association between high concentrations of early pregnancy steroid hormones and risk of ER(-)/PR(-) breast cancer in women diagnosed age pregnancy hormones and risk of steroid receptor-negative cancers is needed to further characterize this association.

  4. Impact of urate level on cardiovascular risk in allopurinol treated patients. A nested case control study

    DEFF Research Database (Denmark)

    Larsen, Kasper Søltoft; Pottegård, Anton; Lindegaard, H. M.;

    2015-01-01

    Background: Gout gives rise to increased risk of adverse cardiovascular outcomes. Gout attacks can be effectively prevented with urate lowering drugs such as allopurinol, and allopurinol further potentially reduces the cardiovascular risk. Whether treatment to a target level of uric acid...

  5. Cardiovascular drugs and the risk of suicide: a nested case-control study

    DEFF Research Database (Denmark)

    Callréus, Torbjörn; Agerskov Andersen, Ulla; Hallas, Jesper

    2007-01-01

    OBJECTIVE: During the past 30 years, various cardiovascular drugs have been implicated as causes of depression or suicide. Although the evidence for causal relationships has generally been conflicting, both beta-blockers and angiotensin-converting-enzyme inhibitors (ACE-inhibitors) have been rela...

  6. Prenatal DDT Exposure and Testicular Cancer: A Nested Case-Control Study

    OpenAIRE

    2010-01-01

    We examined maternal serum levels of DDT-related compounds in relation to son's risk of testicular cancer 30 years later. Fifteen of 9,744 live-born sons were diagnosed with germ cell testicular cancer and had maternal serum samples. Cases were matched to three controls on race and birth year. Maternal serum DDT-related compounds, measured in the early postpartum, were associated with her son's risk of testicular cancer. Despite low statistical power, we observed that mothers of cases had a s...

  7. Prenatal DDT exposure and testicular cancer: a nested case-control study.

    Science.gov (United States)

    Cohn, Barbara A; Cirillo, Piera M; Christianson, Roberta E

    2010-01-01

    The authors examined maternal serum levels of DDT-related compounds in relation to son's risk of testicular cancer 30 years later. Fifteen of 9,744 live-born sons were diagnosed with germ cell testicular cancer and had maternal serum samples. Cases were matched to three controls on race and birth year. Maternal serum DDT-related compounds, measured in the early postpartum, were associated with her son's risk of testicular cancer. Despite low statistical power, we observed that mothers of cases had a significantly higher ratio of p,p'-DDT (1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane) to p,p'-DDE (1,1'-dichloro-2,2'-bis(p-chlorophenyl)ethylene) and lower o,p'-DDT (1,1,1-tricholoro-2-(p-chlororphenyl)-2-(o-chlorophenyl)ethane). These findings are consistent with earlier exposure to DDT and with slower p,p'-DDT elimination among mothers of cases. Whether these associations could be direct, or operate via other pathways is unknown. Further research on interindividual differences in DDT metabolism could provide clues to testicular cancer etiology.

  8. [Influential factors for anemia in pregnancy based on a nested case-control study in Changsha].

    Science.gov (United States)

    Tan, Shan; Li, Hongyan; Gao, Xiao; Xiang, Shiting; He, Qiong; Zhang, Li; Huang, Li; Xiong, Changhui; Yan, Qiang; Yan, Yan

    2016-06-28

    目的:探讨长沙市妇女妊娠期贫血的发生状况及其影响因素,为有针对性地制定预防策略提供科学依据。方法:随机整群抽取长沙市开福区3个街道2013年1月1日至2013年12月31日分娩的713例产妇,建立队列,于产后15 d内回顾性收集其孕期健康信息。采用回顾性巢式病例对照研究方法,应用条件logistic回归分析妊娠期贫血发生的影响因素。结果:长沙市妇女妊娠期贫血患病率为9.96%。多因素条件logistic回归结果显示:家庭人均月收入高(OR=0.632,P=0.020)、文化程度高(OR=0.276,P=0.033)、补叶酸(OR=0.248,P=0.050)、补铁(OR=0.272,P<0.001)及食用血制品(OR=0.588,P=0.044)是妊娠期贫血发生的保护因素,经产妇(OR=2.917,P=0.003)、孕前月经持续时间长(OR=1.335,P=0.041)、住房新装修(OR=3.690,P=0.045)及饮茶(OR=1.365,P=0.094)是妊娠期贫血发生的危险因素。结论:长沙市妇女妊娠期贫血的患病率处于中下水平。妊娠期贫血的发生与妇女的经济水平与营养状况密切相关,孕产妇加强孕期营养及居室环境监测,少喝浓茶,改善铁的营养状况,可预防或降低妊娠期贫血的发生。.

  9. Host biomarkers are associated with progression to dengue haemorrhagic fever: a nested case-control study

    Directory of Open Access Journals (Sweden)

    Andrea L. Conroy

    2015-11-01

    Conclusions: These results suggest that inflammation and endothelial activation are important pathways in the pathogenesis of dengue and sICAM-1 levels may identify individuals at risk of plasma leakage.

  10. Plasma Enterolignan Concentrations and Colorectal Cancer Risk in a Nested Case-Control Study

    NARCIS (Netherlands)

    Kuijsten, A.; Hollman, P.C.H.; Boshuizen, H.C.; Buijsman, M.N.C.P.; Veer, van 't P.; Kok, F.J.; Arts, I.C.W.; Bueno-de-Mesquita, H.B.

    2008-01-01

    Enterolignans are biphenolic compounds that possess several biologic activities whereby they may influence carcinogenesis. The authors investigated the association between plasma enterolactone and enterodiol and colorectal cancer risk in a Dutch prospective study. Among more than 35,000 participants

  11. Maximum likelihood estimation for Cox's regression model under nested case-control sampling

    DEFF Research Database (Denmark)

    Scheike, Thomas Harder; Juul, Anders

    2004-01-01

    -like growth factor I was associated with ischemic heart disease. The study was based on a population of 3784 Danes and 231 cases of ischemic heart disease where controls were matched on age and gender. We illustrate the use of the MLE for these data and show how the maximum likelihood framework can be used...

  12. The -149C>T polymorphism of DNMT3B is not associated with colorectal cancer risk: Evidence from a meta-analysis based on case-control studies.

    Science.gov (United States)

    Fang, Chunyan; Sun, Wenqi; Han, Huirong; Shi, Lihong; Wang, Lin; Zhao, Yan; Tan, Yang

    2012-10-01

    The aim of this study was to examine the association between the -149C>T polymorphism of DNA methyltransferase 3B (DNMT3B) and colorectal cancer (CRC) susceptibility. A comprehensive search was conducted to identify all case-control studies of the -149C>T polymorphism of DNMT3B and CRC risk. Statistical analysis was performed with the software program Stata (version 12.0) and Review Manager (version 5.0). A total of seven eligible studies, including 2,666 cases and 4,022 controls, associating the DNMT3B polymorphism of -149C>T with the risk of CRC were identified. These studies suggested no significant associations between the -149C>T polymorphism of the DNMT3B gene and the risk of developing CRC in the recessive, dominant and co-dominant models [for CC vs. TT: odds ratio (OR), 0.90; 95% confidence interval (CI), 0.90-1.25; P=0.37; for the recessive model: OR, 0.54, 95% CI, 0.28-1.04; PT polymorphism in DNMT3B and CRC susceptibility.

  13. Nest predators, nest-site selection andnest success ofthe Emei Shan Liocichla (Liocichla omeiensis), a vulnerable babbler endemic tosouthwestern China

    Institute of Scientific and Technical Information of China (English)

    Yiqiang Fu; Benping Chen; Simon D Dowell; Zhengwang Zhang

    2016-01-01

    Background: The Emei Shan Liocichla (Liocichla omeiensis) is a globally vulnerable babbler, endemic to southwest-ern China. We investigated its nest predators, nest-site selection and nest success at the Laojunshan National Nature Reserve in Sichuan, China in order to identify the precise nesting-habitat requirements of the species, and to test whether the nest-site-selection cues, preferred by the Emei Shan Liocichla, are positively associated with nest success. Methods: We used infrared cameras to determine nest predators. We compared the microhabitat attributes between nest and random sites, as well as successful and failed nests. We used Binary Logistic Regression to determine the most important variables affecting nest-site selection of the Emei Shan Liocichla. We used the nest survival analysis in Program MARK to estimate daily nest survival rates (DSR). Nest success was calculated using the Mayifeld method. Results: In total 56 nests were found. The DSR for all nests that contained at least one egg was 0.9564± 0.0091 (95 % CI 0.9346–0.9711) (n= 40), while the total nest success was 27.5 %. We identiifed four categories of predators in 10 nest predation events, i.e. squirrels (n= 5), snakes (n= 3), raptors (n= 1) and wasps (n= 1). We found that: (1) nest predation was the primary reason for nest failure of the Emei Shan Liocichla, (2) tree cover, bamboo cover, liana abun-dance and distance to forest edge or gap were the most important variables affecting nest-site selection of this spe-cies, and (3) the nest-site-selection variables we measured appeared not to be positively associated with nest success. Conclusions: Our ifndings suggest that the Emei Shan Liocichla tended to select nest sites near forest edges or gaps with good concealment and that nest-site selection by this species was nonrandom but not necessarily adap-tive. Reducing forest-edge development and protecting bamboo stands should be effective for conservation of this species.

  14. 一种“用例+控例”驱动的软件分析与设计方法%"Use Case+Control Case" Driven Approach for Software Analysis and Design

    Institute of Scientific and Technical Information of China (English)

    刘春; 张伟; 赵海燕; 金芝

    2013-01-01

    As software systems and their operational environments become more and more complex,the topic of software dependability has attracted more and more attention.The software analysis and design are both required to focus on the functionality and the dependability.However,there still lacks an effective approach to consider the functionality and the dependability simultaneously during software analysis and design.Based on cybernetics,this paper proposes a "use case+control case" driven approach for software analysis and design,which aims to address the software functionality and dependability under a unified framework.During requirements analysis,the "use case+control case" model supports the co-modeling of the functional requirements and the dependability requirements.During system design,the design techniques proposed by ICONIX approach are extended to identify the functionality objects that realize the use cases,and the dependability objects that realize the control cases.A case is also used to illustrate the feasibility of the proposed approach.%随着软件本身及其运行环境的日益复杂,软件可信性引起人们越来越多的关注.软件的分析与设计也越来越需要综合考虑软件的功能性和可信性.然而,如何在软件的分析与设计过程中综合考虑软件的功能性和可信性,目前仍然缺乏系统而有效的方法.基于控制论,提出了一种基于“用例+控例”的方法,以在软件的分析与设计过程中综合考虑软件的功能性和可信性.在需求分析阶段,“用例+控例”模型支持需求工程师在同一个模型中自然地表达软件系统的功能性需求和可信性需求.在系统设计阶段,扩展了ICONIX开发方法的用例驱动的系统设计技术,用以分别识别实现用例的功能对象和实现控例的可信保障对象,以最终构建出既满足功能性需求又满足可信性需求的对象模型.应用一个实例来说明所提出方法的可行性.

  15. Serenbe Nest Cottages

    Energy Technology Data Exchange (ETDEWEB)

    Butler, T.; Curtis, O.; Kim, E.; Roberts, S.; Stephenson, R.

    2012-12-01

    As part of the NAHB Research Center Industry Partnership, Southface partnered with Martin Dodson Builders and the Serenbe community on the construction of a new test home in the suburbs of Atlanta, GA in the mixed humid climate zone. The most recent subdivision within the Serenbe community, the Nest, will contain 15 small footprint cottage style homes, and Southface has selected Lot Nine, as the test home for this study. This Nest subdivision serves as a project showcase for both the builder partner and the Serenbe community as a whole. The planning and design incorporated into the Nest cottages will be implemented in each home within the subdivision. These homes addresses Building America Savings targets and serve as a basis of design for other homes Martin Dodson plans to build within the Serenbe community.

  16. Analysis of bacterial community structures in two sewage treatment plants with different sludge properties and treatment performance by nested PCR-DGGE method

    Institute of Scientific and Technical Information of China (English)

    LIU Xin-chun; ZHANG Yu; YANG Min; WANG Zhen-yu; LV Wen-zhou

    2007-01-01

    The bacterial community structures in two sewage treatment plants with different processes and performance were investigated by denaturing gradient gel electrophoresis (DGGE) of nested polymerase chain reaction (nested PCR) amplified 16S rRNA gene fragments with group-specific primers. Samples of raw sewage and treated effluents were amplified using the whole-cell PCR method, and the activated sludge samples were amplified using the extracted genomic DNA before the PCR products were loaded on the same DGGE gel for bacterial community analysis. Ammonia-oxidizing bacterial and actinomycetic community analysis were also carried out to investigate the relationship between specific population structures and system or sludge performance. The two plants demonstrated a similarity in bacterial community structures of raw sewage and activated sludge, but they had different effluent populations. Many dominant bacterial populations of raw sewage did not appear in the activated sludge samples, suggesting that the dominant bacterial populations in raw sewage might not play an important role during wastewater treatment. Although the two plants had different sludge properties in terms of settleability and foam forming ability, they demonstrated similar actinomycetic community structures. For activated sludge with bad settling performance, the treated water presented a similar DGGE pattern with that of activated sludge, indicating the nonselective washout of bacteria from the system. The plant with better ammonium removal efficiency showed higher ammonia-oxidizing bacteria (AOB) species richness. Analysis of sequencing results showed that the major populations in raw sewage were uncultured bacterium, while in activated sludge the predominant populations were beta proteobacteria.

  17. The Glioma International Case-Control Study

    DEFF Research Database (Denmark)

    Amirian, E Susan; Armstrong, Georgina N; Zhou, Renke

    2016-01-01

    describe the Glioma International Case-Control (GICC) Study (recruitment, 2010-2013), a study being conducted by the Genetic Epidemiology of Glioma International Consortium that integrates data from multiple data collection sites, uses a common protocol and questionnaire, and includes biospecimen...

  18. Facial dermatosis associated with Demodex: a case-control study*

    OpenAIRE

    Zhao, Ya-e; Peng, Yan; Wang, Xiang-lan; Wu, Li-ping; Wang, Mei; Yan, Hu-ling; Xiao, Sheng-xiang

    2011-01-01

    Demodex has been considered to be related with multiple skin disorders, but controversy persists. In this case-control study, a survey was conducted with 860 dermatosis patients aged 12 to 84 years in Xi’an, China to identify the association between facial dermatosis and Demodex. Amongst the patients, 539 suffered from facial dermatosis and 321 suffered from non-facial dermatosis. Demodex mites were sampled and examined using the skin pressurization method. Multivariate regression analysis wa...

  19. Hodgkin's disease: case control epidemiological study in Yorkshire.

    OpenAIRE

    Bernard, S.M.; Cartwright, R. A.; Darwin, C. M.; Richards, I D; Roberts, B; O'Brien, C; Bird, C. C.

    1987-01-01

    This is the first report of a case-control epidemiological study on lymphomas and leukaemias occurring in Yorkshire during 1979-84. This paper deals with the results of the Hodgkin's disease analysis comprising 248 cases and 489 controls. The results indicate support for previous work with respect to small family size and past history of infectious mononucleosis. Positive observations made in a previous pilot study are also confirmed and extended with respect to associations with certain chro...

  20. Duration of Diabetes and Pancreatic Cancer in a Case-Control Study in the Midwest and the Iowa Women's Health Study (IWHS Cohort

    Directory of Open Access Journals (Sweden)

    Sarah A Henry

    2013-05-01

    Full Text Available Context Studies have shown a relationship between history of diabetes and the risk of pancreatic cancer; however, the temporal relation between diabetes and pancreatic cancer is not clearly established. Objectives Diabetes and diabetes duration were examined in relation to pancreatic cancer in a population-based case-control study and prospective cohort. Methods Case-control study: pancreatic cancer cases (n=200 from the Midwest were frequency matched by age and sex to population controls (n=673. Logistic regression yielded odds ratios (ORs and 95% confidence intervals (95% CI. Iowa Women’s Health Study (IWHS cohort: 292 incident pancreatic cancer cases occurred between 1986-2008 among 36,084 post-menopausal, initially cancer-free women. Diabetes status and diagnosis age were ascertained at baseline and follow-ups. Proportional hazards regression yielded hazard ratios (HR, 95% CI for pancreatic cancer in relation to baseline diabetes. Time-dependent analyses accounted for diabetes diagnosed after baseline. A nested-case control analysis assessed diabetes duration as a risk factor. Results In the case-control study, compared to participants without diabetes, the multivariate ORs (95% CI for pancreatic cancer were 2.35 (1.24-4.47 for those with diabetes and 4.00 (0.94-16.9, 2.79 (0.97-8.04, and 2.40 (0.97-5.98 for diabetes durations of 2-5 years, 5.1-10 years, and more than 10 years, respectively. In IWHS, compared to no diabetes, multivariate-adjusted HRs for pancreatic cancer were 1.86 (1.23-2.83 for baseline diabetes and 1.94 (1.40-2.69 adding diabetes during follow-up. In an IWHS nested case-control analysis, ORs were 1.70 (0.78- 3.67, 2.62 (1.48-4.65, and 2.10 (1.36-3.24 for diabetes durations of 2-5 years, 5.1-10 years and more than 10 years, respectively, versus no diabetes. Conclusions Diabetes is associated with pancreatic cancer risk and this is similar across different duration categories.

  1. High Prevalence of Human Papillomavirus in Colorectal Cancer in Hispanics: A Case-Control Study

    Directory of Open Access Journals (Sweden)

    Raul D. Bernabe-Dones

    2016-01-01

    Full Text Available The role of Human Papillomavirus (HPV in colorectal carcinogenesis remains elusive. Based on the high incidence of HPV-associated malignancies among Puerto Rican Hispanics, this study aimed to assess the prevalence of HPV infection and viral integration in colorectal tissues in order to evaluate its putative role in colorectal cancer (CRC. In this case-control study, the prevalence of HPV infection in CRC (cases n = 45 and normal colon mucosa from cancer-free subjects (controls n = 36 was assessed by a nested PCR strategy. HPV-16 genotyping was performed in HPV-positive tissues and the physical status of the HPV-16 genome was determined by E2 detection. HPV was detected in 19 of 45 (42.2% CRC cases (mean age 61.1 ± 10.7 years, 24 males and in 1 of 36 (2.8% controls (mean age 60.9 ± 9.6 years, 24 males with an OR = 25.58 (95% CI 3.21 to 203.49. HPV-16 was detected in 63.2% of the HPV-positive colorectal tumors; genome integration was observed in all HPV-16 positive cases. This is the first report showing the high prevalence of HPV infections in Caribbean Hispanic colorectal tumors. Despite evidence of HPV integration into the host genome, further mechanistic analysis examining HPV oncoprotein expression and the putative role of these oncoproteins in colorectal carcinogenesis is warranted.

  2. Association between Periodontal Disease and Stroke: A Meta-analysis of Case-control Studies%牙周病与卒中相关性的病例-对照研究的Meta分析

    Institute of Scientific and Technical Information of China (English)

    李薇; 毛敏; 任昌菊; 刘彩云; 严艳

    2012-01-01

    Objective To explore the association between periodontal disease and stroke by performing a meta-analysis. Methods Two authors independently searched the PubMed, Embase, CNKI, CBM, Wanfang, and VIP databases to collect the relevant case-control studies up to April 4th, 2012. After quality assessment of included studies and data extraction, a meta-analysis was performed by using the Comprehensive Meta Analysis V2 software, and the level of evidence was evaluated by using the GRADE system. Results Five engb'sh studies met the criterion. Meta-analysis showed that exposure to periodontal disease could obviously increase 3.93 times risk of incident stroke (OR = 3. 94,95 % CI = 2. 64 - 5. 88, P < 0. 001) , the level of evidence was " morderate quality" . Conclusion Current evidences show that periodontal disease is an independent and significant risk fator for stroke. Further studies according to the degrees of periodontal disease and the clinical subtypes of stroke are needed.%目的:采用Meta分析的方法评价牙周病与卒中的相关性.方法:由两名评价者独立检索PubMed、Embase、中国知网、中国生物医学文献数据库、万方数据库、维普数据库中公开发表的探讨牙周病与卒中相关性的病例-对照研究,对符合纳入标准的文献采用NOS标准进行质量评价及数据提取后,采用Comprehensive Meta Analysis V2软件进行Meta分析,并采用GRADE系统进行证据评级.结果:共纳入病例对照研究5个,均为英文.Meta分析结果显示暴露于牙周病可以显著提高卒中发生率3.93倍(OR =3.94,95% CI =2.64 -5.88,P<0.001),证据等级为“中级”.结论:牙周病是卒中的一个独立的、有意义的危险因子.建议未来的研究能够按照牙周病临床程度分级和卒中临床亚型分型.

  3. Association between the European GWAS-identified susceptibility locus at chromosome 4p16 and the risk of atrial septal defect: a case-control study in Southwest China and a meta-analysis.

    Directory of Open Access Journals (Sweden)

    Li Zhao

    Full Text Available Atrial septal defect (ASD is the third most frequent type of congenital heart anomaly, featuring shunting of blood between the two atria. Gene-environment interaction remains to be an acknowledged cause for ASD occurrence. A recent European genome-wide association study (GWAS of congenital heart disease (CHD identified 3 susceptibility SNPs at chromosome 4p16 associated with ASD: rs870142, rs16835979 and rs6824295. A Chinese-GWAS of CHD conducted in the corresponding period did not reveal the 3 susceptibility SNPs, but reported 2 different risk SNPs: rs2474937 and rs1531070. Therefore, we aimed to investigate the associations between the 3 European GWAS-identified susceptibility SNPs and ASD risk in the Han population in southwest China. Additionally, to increase the robustness of our current analysis, we conducted a meta-analysis combining published studies and our current case-control study. We performed association, linkage disequilibrium, and haplotype analysis among the 3 SNPs in 190 ASD cases and 225 age-, sex-, and ethnicity-matched healthy controls. Genotype and allele frequencies among the 3 SNPs showed statistically significant differences between the cases and controls. Our study found that individuals carrying the allele T of rs870142, the allele A of rs16835979, and the allele T of rs6824295 had a respective 50.1% (odds ratio (OR = 1.501, 95% confidence interval (CI = 1.122-2.009, PFDR-BH = 0.018, 48.5% (OR = 1.485, 95%CI = 1.109-1.987, PFDR-BH = 0.012, and 38.6% (OR = 1.386, 95%CI = 1.042-1.844, PFDR-BH = 0.025 increased risk to develop ASD than wild-type allele carriers in our study cohort. In the haplotype analysis, we identified a disease-risk haplotype (TAT (OR = 1.540, 95%CI = 1.030-2.380, PFDR-BH = 0.016. Our meta-analysis also showed that the investigated SNP was associated with ASD risk (combined OR (95%CI = 1.35 (1.24-1.46, P < 0.00001. Our study provides compelling evidence to motivate better understanding of the etiology

  4. Feathering Your Nest

    Science.gov (United States)

    Nabors, Martha L.; Edwards, Linda Carol; Decker, Suzanne

    2010-01-01

    The first-grade classroom was like a natural history museum. Bird nests of every shape and size lay on top of bookshelves that lined two walls. Methods students, who were visiting the classroom in preparation for the science lessons they would teach there, were immediately inspired by the collection. They used the collection as a springboard for…

  5. Incremental cost-effectiveness of cyclooxygenase 2-selective versus nonselective nonsteroidal, anti-inflammatory drugs in a cohort of coumarin users : A pharmacoeconomic analysis linked to a case-control study

    NARCIS (Netherlands)

    Knijff-Dutmer, EAJ; Postma, MJ; van der Palen, J; Brouwers, JRBJ; van de Laar, MAFJ

    2004-01-01

    Background: A previous case-control study involving concomitant users of coumarin and nonsteroidal anti-inflammatory drugs (NSAIDs) found that cyclooxygenase 2 (COX-2)-selective NSAIDs were associated with fewer bleeding complications than nonselective NSAIDs. Objective: The goal of this study was t

  6. Incremental cost-effectiveness of cyclooxygenase 2-selective versus nonselective nonsteroidal anti-inflammatory drugs in a cohort of coumarin users: A pharmacoeconomic analysis linked to a case-control study

    NARCIS (Netherlands)

    Knijff-Dutmer, Ellen A.J.; Postma, Maarten J.; Palen, van der Job; Brouwers, Jacobus R.B.J.; Laar, van de Martin A.F.J.

    2004-01-01

    Background: A previous case-control study involving concomitant users of coumarin and nonsteroidal anti-inflammatory drugs (NSAIDs) found that cyclooxygenase 2 (COX-2)-selective NSAIDs were associated with fewer bleeding complications than nonselective NSAIDs. Objective: The goal of this study was

  7. Nested PCR detection and phylogenetic analysis of Babesia bovis and Babesia bigemina in cattle from Peri-urban localities in Gauteng Province, South Africa.

    Science.gov (United States)

    Mtshali, Phillip Senzo; Tsotetsi, Ana Mbokeleng; Thekisoe, Matlhahane Molifi Oriel; Mtshali, Moses Sibusiso

    2014-01-01

    Babesia bovis and Babesia bigemina are tick-borne hemoparasites causing babesiosis in cattle worldwide. This study was aimed at providing information about the occurrence and geographical distribution of B. bovis and B. bigemina species in cattle from Gauteng province, South Africa. A total of 268 blood samples collected from apparently healthy animals in 14 different peri-urban localities were tested using previously established nested PCR assays for the detection of B. bovis and B. bigemina species-specific genes encoding rhoptry-associated protein 1 (RAP-1) and SpeI-AvaI restriction fragment, respectively. Nested PCR assays revealed that the overall prevalence was 35.5% (95% confidence interval [CI]=± 5.73) and 76.1% (95% CI=± 5.11) for B. bovis and B. bigemina, respectively. PCR results were corroborated by sequencing amplicons of randomly selected samples. The neighbor-joining trees were constructed to study the phylogenetic relationship between B. bovis and B. bigemina sequences of randomly selected isolates. Analysis of phylogram inferred with B. bovis RAP-1 sequences indicated a close relationship between our isolates and GenBank strains. On the other hand, a tree constructed with B. bigemina gp45 sequences revealed a high degree of polymorphism among the B. bigemina isolates investigated in this study. Taken together, the results presented in this work indicate the high incidence of Babesia parasites in cattle from previously uncharacterised peri-urban areas of the Gauteng province. These findings suggest that effective preventative and control measures are essential to curtail the spread of Babesia infections among cattle populations in Gauteng.

  8. Metodologia caso-controle em epidemiologia de doenças cardiovasculares: II - Análise de dados Case-control design in cardiovascular disease epidemiology: II - Analysis of data

    Directory of Open Access Journals (Sweden)

    Suzana Alves de Moraes

    1998-02-01

    Full Text Available A larga difusão, nos últimos anos, de softwares estatísticos indicados para análises multivariadas, aliada à facilidade de seu manuseio, poderá conduzir os usuários à obtenção de estimativas enganosas caso não se conheçam os pressupostos teóricos necessários para o emprego destas técnicas. Com o propósito de se destacar alguns desses pressupostos, apresentam-se as etapas executadas para a análise dos dados de um estudo caso-controle, conduzido no Município de São Paulo, entre março de 1993 e fevereiro de 1994, cujo objetivo foi testar a associação do diabetes mellitus com a doença isquêmica do coração após o ajustamento para possíveis variáveis de confusão e/ou modificadoras de efeito. Para uma melhor visualização didática desses pressupostos metodológicos são destacadas quatro etapas fundamentais durante a fase de análise dos dados: a construção do banco de dados; b cálculo do poder estatístico; c categorização e codificação das variáveis e d a escolha do modelo de regressão logística multivariada.The widespread distribution of statistical software recommended for multivariate analysis as well as the ease in handling it can lead the users into adopting wrong measures if they do not pay attention to the theoretical principles behind those methods. With a view to bringing out some of these principles some steps for the data analysis of a case-control study undertaken in the city of S. Paulo-Brazil from March, 1993 to February, 1994 in order to test the association between diabetes mellitus and ischaemic heart disease after adjusting for potential confounders and/or modifiers of effect are presented. Methodologic issues are emphasized in the development of four steps: a the data bank structure; b the calculation of statistical power; c the definition of variables strata and codification and d the choice of the logistic regression method.

  9. Simulated nests in wildlife management

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Many of us have studied game bird nests. Usually we hoped to learn something about nesting cover, cover management and the birds and animals which seemed to eat the...

  10. Preliminary evaluation of a nest usage sensor to detect double nest occupations of laying hens.

    Science.gov (United States)

    Zaninelli, Mauro; Costa, Annamaria; Tangorra, Francesco Maria; Rossi, Luciana; Agazzi, Alessandro; Savoini, Giovanni

    2015-01-26

    Conventional cage systems will be replaced by housing systems that allow hens to move freely. These systems may improve hens' welfare, but they lead to some disadvantages: disease, bone fractures, cannibalism, piling and lower egg production. New selection criteria for existing commercial strains should be identified considering individual data about laying performance and the behavior of hens. Many recording systems have been developed to collect these data. However, the management of double nest occupations remains critical for the correct egg-to-hen assignment. To limit such events, most systems adopt specific trap devices and additional mechanical components. Others, instead, only prevent these occurrences by narrowing the nest, without any detection and management. The aim of this study was to develop and test a nest usage "sensor", based on imaging analysis, that is able to automatically detect a double nest occupation. Results showed that the developed sensor correctly identified the double nest occupation occurrences. Therefore, the imaging analysis resulted in being a useful solution that could simplify the nest construction for this type of recording system, allowing the collection of more precise and accurate data, since double nest occupations would be managed and the normal laying behavior of hens would not be discouraged by the presence of the trap devices.

  11. Preliminary Evaluation of a Nest Usage Sensor to Detect Double Nest Occupations of Laying Hens

    Directory of Open Access Journals (Sweden)

    Mauro Zaninelli

    2015-01-01

    Full Text Available Conventional cage systems will be replaced by housing systems that allow hens to move freely. These systems may improve hens’ welfare, but they lead to some disadvantages: disease, bone fractures, cannibalism, piling and lower egg production. New selection criteria for existing commercial strains should be identified considering individual data about laying performance and the behavior of hens. Many recording systems have been developed to collect these data. However, the management of double nest occupations remains critical for the correct egg-to-hen assignment. To limit such events, most systems adopt specific trap devices and additional mechanical components. Others, instead, only prevent these occurrences by narrowing the nest, without any detection and management. The aim of this study was to develop and test a nest usage “sensor”, based on imaging analysis, that is able to automatically detect a double nest occupation. Results showed that the developed sensor correctly identified the double nest occupation occurrences. Therefore, the imaging analysis resulted in being a useful solution that could simplify the nest construction for this type of recording system, allowing the collection of more precise and accurate data, since double nest occupations would be managed and the normal laying behavior of hens would not be discouraged by the presence of the trap devices.

  12. Bed-sharing in the absence of hazardous circumstances: is there a risk of sudden infant death syndrome? An analysis from two case-control studies conducted in the UK.

    Directory of Open Access Journals (Sweden)

    Peter S Blair

    Full Text Available OBJECTIVE: The risk of sudden infant death syndrome (SIDS among infants who co-sleep in the absence of hazardous circumstances is unclear and needs to be quantified. DESIGN: Combined individual-analysis of two population-based case-control studies of SIDS infants and controls comparable for age and time of last sleep. SETTING: Parents of 400 SIDS infants and 1386 controls provided information from five English health regions between 1993-6 (population: 17.7 million and one of these regions between 2003-6 (population:4.9 million. RESULTS: Over a third of SIDS infants (36% were found co-sleeping with an adult at the time of death compared to 15% of control infants after the reference sleep (multivariate OR = 3.9 [95% CI: 2.7-5.6]. The multivariable risk associated with co-sleeping on a sofa (OR = 18.3 [95% CI: 7.1-47.4] or next to a parent who drank more than two units of alcohol (OR = 18.3 [95% CI: 7.7-43.5] was very high and significant for infants of all ages. The risk associated with co-sleeping next to someone who smoked was significant for infants under 3 months old (OR = 8.9 [95% CI: 5.3-15.1] but not for older infants (OR = 1.4 [95% CI: 0.7-2.8]. The multivariable risk associated with bed-sharing in the absence of these hazards was not significant overall (OR = 1.1 [95% CI: 0.6-2.0], for infants less than 3 months old (OR = 1.6 [95% CI: 0.96-2.7], and was in the direction of protection for older infants (OR = 0.1 [95% CI: 0.01-0.5]. Dummy use was associated with a lower risk of SIDS only among co-sleepers and prone sleeping was a higher risk only among infants sleeping alone. CONCLUSION: These findings support a public health strategy that underlines specific hazardous co-sleeping environments parents should avoid. Sofa-sharing is not a safe alternative to bed-sharing and bed-sharing should be avoided if parents consume alcohol, smoke or take drugs or if the infant is pre-term.

  13. Fatores associados à rosácea em amostras populacionais do Sul do Brasil: análise de estudos casos-controles Factors associated with rosacea in population samples of Southern Brazil: analysis of case-control studies

    Directory of Open Access Journals (Sweden)

    Renan Rangel Bonamigo

    2008-10-01

    Full Text Available FUNDAMENTOS: A rosácea é dermatose que apresenta uma série de variáveis associadas a seu surgimento. A maioria dos estudos é proveniente dos Estados Unidos da América e de países europeus, sendo escasso o conhecimento produzido e publicado acerca da doença no Hemisfério Sul, particularmente no Brasil. OBJETIVOS: Descrever os principais fatores clínicos e histopatológicos associados à rosácea em amostras populacionais do sul do Brasil. MÉTODOS: Dois estudos casos-controles realizados em seqüência, com análise univariada e bivariada, utilizando-se p BACKGROUND: Rosacea is a dermatosis that has many factors associated with its onset. Most studies on this condition come from the United States and European countries, with little information produced and published about the disease in the Southern hemisphere, particularly in Brazil. OBJECTIVES: To describe the main clinical and histopathological factors associated with rosacea in population samples from southern Brazil. METHODS: Two case-control studies performed sequentially, with univariate and bivariate analysis, using p<0.05 for statistical significance (Chi-square test and Mantel-Haenzel, for stratifications RESULTS: Rosacea is most frequent among women and in the age range of 40-50 years. Almost all cases have phototypes II and III. The inflammatory forms of rosacea are more often diagnosed than the vascular form and there is an association with serological positivity to Helicobacter pylori and with histopathological presence of Demodex folliculorum (p<0.05. Emotional and climatic changes, exposure to the sun and intake of alcoholic beverages were the main factors described as provoking or worsening the disease. CONCLUSIONS: We have obtained an overview of rosacea in a sample of the southern population of Brazil. While some data are similar to those already described internationally, other aspects, such as economic issues and the factors described as provoking or worsening the

  14. Case-control study on factors associated with crown fractures in the primary dentition

    Directory of Open Access Journals (Sweden)

    Patrícia CORRÊA-FARIA

    2015-01-01

    Full Text Available The purpose of the present study was to identify the factors associated with dental trauma in preschool children. This case-control study was nested in a population-based cross-sectional study involving a random sample of 301 children one to five years of age in the city of Diamantina, Brazil. The case group was made up of children with at least one fractured deciduous tooth, and the control group was made up of children with no deciduous tooth fracture. The two groups were matched for age in a proportion of one control for every case. The dependent variable was “dental trauma,” diagnosed according to the criteria proposed by Andreasen and Andreasen. The independent variables were overjet, measured and considered accentuated when surpassing 3 mm, and lip coverage, classified as adequate or inadequate. Clinical oral examinations were performed by calibrated dentists. The parents provided information on the socioeconomic indicators. Statistical analysis involved the McNemar test and logistic regression. Each group (case and control was composed of 92 children. In the bivariate analysis, traumatic dental injury (TDI was associated with overjet > 3 mm (p = 0.001, inadequate lip coverage (p < 0.001, mother's schooling (p = 0.028 and household income (p < 0.001. In the multivariate analysis, only inadequate lip coverage was associated with TDI (OR: 5.35; 95% CI: 1.37-20.85. In conclusion, the case group children had a 5.3 - fold more likely chance of presenting inadequate lip coverage, compared with the control children.

  15. Choroidal thickness and central serous chorioretinopathy:a case-control study and Meta-analysis%脉络膜厚度与CSCR的病例对照研究与Meta分析

    Institute of Scientific and Technical Information of China (English)

    叶汉元; 杨安怀

    2015-01-01

    目的:定量分析中心性浆液性脉络膜视网膜病变( central serous chorioretinopathy,CSCR)患者黄斑中心凹下脉络膜厚度( subfoveal choroidal thickness,SFCT)改变。  方法:采用病例对照研究及Meta分析。连续的CSCR患者46例纳入研究,CSCR患者散瞳后前置镜眼底检查,荧光素眼底血管造影和吲哚菁绿血管造影检查确诊。选择同期年龄、性别、屈光度及眼轴匹配的正常人62例62眼作为正常对照组。用加强成像深度扫描OCT检测并比较CSCR组及对照组SFCT。单因素和多因素分析 SFCT 与各临床资料之间的关系。 Meta分析用Stata软件计算两组之间的加权均数差。  结果:CSCR患者的平均SFCT为397.34±83.91μm,正常对照组为274.48±62.57μm。 CSCR组SFCT较对照组明显增厚,差异有统计学意义(P  结论:CSCR患者黄斑中央凹下脉络膜较正常眼厚,增厚的SFCT与CSCR诊断存在相关性。%AIM:To investigate the changes of subfoveal choroidal thickness ( SFCT ) in central serous chorioretinopathy ( CSCR) eyes and to compare them with normal control eyes. METHODS: This was a case-control study and a Meta-analysis. Forty - six CSCR patients diagnosed by the fundus pre - set lens, fundus fluorescein angiography (FFA) and indocyanine green angiography (ICGA) were enrolled in this study. Sixty two age-, sex-, diopter- and axial length-matched 62 normal subjects ( 62 eyes ) were enrolled in this study as the control group. Using enhanced depth imaging optical coherence tomography ( EDI-OCT) , SFCT of CSCR eyes and normal control eyes were measured and compared. Univariate and multivariate linear regression analysis were performed to assess the association between SFCT and clinical factors. The Meta - analysis were conducted using the Stata software package to calculate the summary weighted mean differences ( WMDs) . RESULTS:The mean SFCT of the CSCR group and the normal control group was 397. 34±83. 91μm and

  16. Nest and nest site characterisitcs of some ground-nesting, non-passerine birds of northern grasslands

    Science.gov (United States)

    Kantrud, H.A.; Higgins, K.F.

    1992-01-01

    We summarized biological and ecologic characteristics of 2490 nests of 16 species of upland-nesting, non-passerine birds of northern grasslands found during 1963 through 1991. Nest initiation and hatch dates, clutch sizes, nest fates, causes of failure, success rates of nests among major habitat types and land uses, and vegetation measurements at nest sites are analyzed.

  17. Case-control study on factors associated with crown fractures in the primary dentition

    OpenAIRE

    2015-01-01

    The purpose of the present study was to identify the factors associated with dental trauma in preschool children. This case-control study was nested in a population-based cross-sectional study involving a random sample of 301 children one to five years of age in the city of Diamantina, Brazil. The case group was made up of children with at least one fractured deciduous tooth, and the control group was made up of children with no deciduous tooth fracture. The two groups were matched for age in...

  18. Intelligent nesting system

    Directory of Open Access Journals (Sweden)

    Đuričić Zoran

    2003-01-01

    Full Text Available The economy of the process for the manufacture of parts from sheet metal plates depends on successful solution of the process of cutting various parts from sheet metal plates. Essentially, the problem is to arrange contours within a defined space so that they take up minimal surface. When taken in this way, the considered problem assumes a more general nature; it refers to the utilization of a flat surface, and it can represent a general principle of arranging 2D contours on a certain surface. The paper presents a conceptual solution and a prototypal intelligent nesting system for optimal cutting. The problem of nesting can generally be divided into two intellectual phases: recognition and classification of shapes, and arrangement of recognized shapes on a given surface. In solving these problems, methods of artificial intelligence are applied. In the paper, trained neural network is used for recognition of shapes; on the basis of raster record of a part's drawing, it recognizes the part's shape and which class it belongs to. By means of the expert system, based on rules defined on the basis of acquisition of knowledge from manufacturing sections, as well as on the basis of certain mathematical algorithms, parts are arranged on the arrangement surface. Both systems can also work independently, having been built on the modular principle. The system uses various product models as elements of integration for the entire system. .

  19. PyNEST: a convenient interface to the NEST simulator

    Directory of Open Access Journals (Sweden)

    Jochen M Eppler

    2009-01-01

    Full Text Available The neural simulation tool NEST (http://www.nest-initiative.org is a simulator for heterogeneous networks of point neurons or neurons with a small number of compartments. It aims at simulations of large neural systems with more than 10^4 neurons and 10^7 to 10^9 synapses. NEST is implemented in C++ and can be used on a large range of architectures from single-core laptops over multi-core desktop computers to super-computers with thousands of processor cores. Python (http://www.python.org is a modern programming language that has recently received considerable attention in Computational Neuroscience. Python is easy to learn and has many extension modules for scientific computing (e.g. http://www.scipy.org. In this contribution we describe PyNEST, the new user interface to NEST. PyNEST combines NEST’s efficient simulation kernel with the simplicity and flexibility of Python. Compared to NEST’s native simulation language SLI, PyNEST makes it easier to set up simulations, generate stimuli, and analyze simulation results. We describe how PyNEST connects NEST and Python and how it is implemented. With a number of examples, we illustrate how it is used.

  20. Nested Canalyzing, Unate Cascade, and Polynomial Functions.

    Science.gov (United States)

    Jarrah, Abdul Salam; Raposa, Blessilda; Laubenbacher, Reinhard

    2007-09-15

    This paper focuses on the study of certain classes of Boolean functions that have appeared in several different contexts. Nested canalyzing functions have been studied recently in the context of Boolean network models of gene regulatory networks. In the same context, polynomial functions over finite fields have been used to develop network inference methods for gene regulatory networks. Finally, unate cascade functions have been studied in the design of logic circuits and binary decision diagrams. This paper shows that the class of nested canalyzing functions is equal to that of unate cascade functions. Furthermore, it provides a description of nested canalyzing functions as a certain type of Boolean polynomial function. Using the polynomial framework one can show that the class of nested canalyzing functions, or, equivalently, the class of unate cascade functions, forms an algebraic variety which makes their analysis amenable to the use of techniques from algebraic geometry and computational algebra. As a corollary of the functional equivalence derived here, a formula in the literature for the number of unate cascade functions provides such a formula for the number of nested canalyzing functions.

  1. 病例对照Meta分析显示男性乳腺癌与女性乳腺癌预后相同%A meta-analysis based on case-control studies shows the similar prognosis between male and female patients with breast cancer

    Institute of Scientific and Technical Information of China (English)

    Feifei Zhou; Rong Huang; Jun Jiang; Fang Wang; Wenzhuo He; Guifang Guo; Liangping Xia

    2011-01-01

    Objective: Male breast cancer (MBC) is a rare disease, and studies to compare the prognosis between the MBC and female breast cancer (FBC) available now were case-control studies and population-based studies, however, with controversial outcomes. To further investigate whether sex affects the prognosis of breast cancer, we performed a meta-analysis based on all the peered papers. Methods: The PubMed database was screened. Subsequently, the hazard ratios (HRs) for overall survival (OS) and disease special survival (DSS), were pooled using the Review Manager 5.0 package. Results: This study comprised of 254 MBC and 733 FBC patients enrolled in six case-control studies. There was no statistically significant heterogeneity among the trials for either outcome variable. The pooled HR showed that there was no significant difference in 5-year or 10-year DSS (HR: 1.25, 95% CI: 0.76-2.08; HR: 1.04, 95% CI: 0.66-1.59) and 5-year or 10-year OS (HR: 0.76, 95%CI: 0.51-1.14; HR: 0.74, 95% CI: 0.54-1.02) between MBCs and FBCs. Conclusion: MBC and FBC with similar prognosis are found in this meta-analysis based on only case-control studies which matched main potential prognostic factors such as age, clinical stage, and time at diagnosis.

  2. Determinants of infant nutritional status in Dabat district, North Gondar, Ethiopia: A case control study

    Science.gov (United States)

    Wubante, Amarech Asratie

    2017-01-01

    Background Malnutrition is the top cause of global burden of disease, disability and mortality among infants. Over two-thirds of deaths of children globally occur during the first year of life (infancy). Malnutrition among infants is substantially high in Ethiopia. Therefore, this study is aimed to assess determinants of infant nutritional status. Methods A community based nested case-control study was conducted from February to June 2013 in Dabat district. A total of 80 cases and 320 controls (1:4 ratios) were studied. Relevant data was extracted from the community based survey data set. Anthroplus software was used to identify cases and controls. Determinants of infant nutritional status were identified using multivariate analysis. Results Among the total of 80 cases and 320 controls, more than half (52.5%) of the cases and the controls (53.8%) were males and females, respectively. Breast Feeding (BF) was started immediately after birth in only 43.8% of the cases. Nearly 94% of the mothers of the cases had no breast feeding information as part of Ante Natal Care (ANC) follow up. Maternal age (AOR: 0.29; 95% CI: 0.11–0.76), having radio (AOR: 0.43; 95% CI: 0.22–0.82), lack of toilet facility (AOR: 2.24; 95% CI: 1.16–4.33), deprivation of colostrum (AOR: 1.76; 95% CI: 1.01–1.06) and method of complementary feeding (AOR: 2.82; 95% CI: 1.33–5.99) were associated with wasting. Conclusions This study has found that inappropriate infant feeding; nutritional information gap and lack of toilet facility as significant predictors of malnutrition. Hence, joint interventions, including counseling of mothers about benefits of colostrum feeding and use of appropriate feeding method, toilet utilization and mass media such as radio possession, are needed to address the problem in Dabat district. PMID:28346497

  3. Alcohol Consumption-Related Metabolites in Relation to Colorectal Cancer and Adenoma: Two Case-Control Studies Using Serum Biomarkers.

    Science.gov (United States)

    Troche, Jose Ramon; Mayne, Susan T; Freedman, Neal D; Shebl, Fatma M; Guertin, Kristin A; Cross, Amanda J; Abnet, Christian C

    2016-01-01

    Alcohol is a known carcinogen that may be associated with colorectal cancer. However, most epidemiologic studies assess alcoholic beverage consumption using self-reported data, leading to potential exposure misclassification. Biomarkers of alcohol consumption may provide an alternative, complementary approach that reduces misclassification and incorporates individual differences in alcohol metabolism. Therefore, we evaluated the relationship between previously identified alcohol consumption-related metabolites and colorectal cancer and adenoma using serum metabolomics data from two studies. Data on colorectal cancer were obtained from a nested case-control study of 502 US adults (252 cases, 250 controls) within the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. Data on colorectal adenoma were obtained from a case-control study of 197 US adults (120 cases, 77 controls) from the Navy Colon Adenoma Study. Unconditional multivariable logistic regression models were fit to calculate odds ratios (OR) and 95% confidence intervals (CI) for eight alcohol consumption-related metabolites identified in a previous analysis: ethyl glucuronide; 4-androstene-3beta,17beta-diol disulfate 1; 5-alpha-androstan-3beta,17beta-diol disulfate; 16-hydroxypalmitate; bilirubin (E,Z or Z,E); cyclo (-leu-pro); dihomo-linoleate (20:2n6); and palmitoleate (16:1n7). We found no clear association between these alcohol consumption-related metabolites and either endpoint. However, we did observe an inverse association between cyclo (-leu-pro) and colorectal adenoma that was only observed in the highest metabolite quantile (OR 4th vs. 1st Quantile = 0.30, 95% CI: 0.12-0.78; P-trend = 0.047), but no association for colorectal cancer. In conclusion, there were no adverse associations between alcohol consumption-related metabolites and colorectal cancer or adenoma.

  4. Venous thromboembolism in adults screened for sickle cell trait: a population-based cohort study with nested case–control analysis

    Science.gov (United States)

    Little, Iain; Vinogradova, Yana; Orton, Elizabeth; Kai, Joe; Qureshi, Nadeem

    2017-01-01

    Objective To determine whether sickle cell carriers (‘sickle cell trait’) have an increased risk of venous thromboembolism (VTE). Design Cohort study with nested case–control analysis. Setting General population with data from 609 UK general practices in the Clinical Practice Research Datalink (CPRD). Participants All individuals registered with a CPRD general practice between 1998 and 2013, with a medical record of screening for sickle cell between 18 and 75 years of age. Main outcomes measures Incidence of VTE per 10 000 person-years (PY) among sickle cell carriers and non-carriers; and adjusted OR for VTE among sickle cell carriers compared with non-carriers. Results We included 30 424 individuals screened for sickle cell, with a follow-up time of 179 503 PY, identifying 55 VTEs in 6758 sickle cell carriers and 125 VTEs in 23 666 non-carriers. VTE incidence among sickle cell carriers (14.9/10 000 PY; 95% CI 11.4 to 19.4) was significantly higher than non-carriers (8.8/10 000 PY; 95% CI 7.4 to 10.4). Restricting analysis to confirmed non-carriers was non-significant, but performed on a small sample. In the case–control analysis (180 cases matched to 1775 controls by age and gender), sickle cell carriers remained at increased risk of VTE after adjusting for body mass index, pregnancy, smoking status and ethnicity (OR 1.78, 95% CI 1.18 to 2.69, p=0.006), with the greatest risk for pulmonary embolism (PE) (OR 2.27, 95% CI 1.17 to 4.39, p=0.011). Conclusions Although absolute numbers are small, in a general population screened for sickle cell, carriers have a higher incidence and risk of VTE, particularly PE, than non-carriers. Clinicians should be aware of this elevated risk in the clinical care of sickle cell carriers, or when discussing carrier screening, and explicitly attend to modifiable risk factors for VTE in these individuals. More complete primary care coding of carrier status could improve analysis. PMID:28360235

  5. A case-control study on the causes of new HIV infection among heroin addicts attendees at the methadone maintenance treatment clinics

    Institute of Scientific and Technical Information of China (English)

    王常合

    2014-01-01

    Objective To explore the routes and factors associated with HIV new infection of heroin addicts who had been attending the methadone maintenance treatment(MMT)program.Methods A 1∶1 nested case-control study was implemented with the cases(new HIV infections)and controls(HIV negative)selected from the treatment cohort of China MMT clients.Questionnaire

  6. 干眼病危险因素的病例对照研究%The risk factors of dry eye in wuhan:a case-control analysis

    Institute of Scientific and Technical Information of China (English)

    杨万举; 杨燕宁; 邢怡桥; 袁静; 肖璇; 曹瑾; 满子惠; 饶卓群

    2012-01-01

    目的 探讨干眼病的危险因素,为干眼的科学预防及其病因学研究提供参考依据.方法 采用以医院为基础的病例对照研究,对在武汉大学人民医院确诊的556例干眼患者,按照年龄和性别1∶1匹配,选取同期门诊或病房非干眼患者556例对照研究,进行统一的问卷调查和相关检查(包括裂隙灯检查、泪膜破裂时间、SchirmerⅠ试验、角膜荧光素染色)获取资料.应用SPSS13.0统计软件包进行单因素和多因素Logistic回归分析.结果 多因素Logistic回归分析显示,丙型肝炎(OR=5.956,95%CI:2.028~17.497)、结缔组织病(OR=2.284,95%CI:1.631~3.197)、创伤后应激障碍(OR=1.750,95%CI:1.144~2.678)、绝经后雌激素治疗(OR=1.945,95%CI:1.022~3.700)、头颈部的放射治疗(OR=6.829,95%CI:1.394~33.448)、抗组胺药(OR=2.133,95%CI:1.452~3.134)、角膜接触镜(OR=6.380,95%CI:2.071~19.657)、视频终端使用超过6h(OR=2.695,95%CI:1.399~5.192)为干眼的独立危险因素;经常食用Ω-3脂肪酸类食物(OR=0.486,95%CI:0.283~0.835)可能为干眼的保护因素.结论 干眼的独立危险因素为丙型肝炎史、结缔组织病史、头颈部的放射治疗、绝经后雌激素治疗、抗组胺药、角膜接触镜、视频终端和创伤后应激障碍;经常食用含Ω-3脂肪酸类食物是干眼的保护因素.本研究结果将有助于临床预防与治疗,对降低干眼的患病率有重要意义.%Objective To explore the risk factors of dry eye, and provide the reference for dry eye scientific prevention and the study of etiology. Methods A hospital-based matched case-control study was earned out in wuhan. Matched by age and sex,556 pairs of cases and controls were recruited and studied. Both cases and controls were interviewed face to face, with uniformed questionnaire and examination( including slit lamp examination, tear film breakup time, Schirmer I test,corneal fluorescein staining). Conditional logistic regression model was used on

  7. Detection and differentiation of field and vaccine strains of canine distemper virus using reverse transcription followed by nested real time PCR (RT-nqPCR) and RFLP analysis.

    Science.gov (United States)

    Fischer, Cristine Dossin Bastos; Ikuta, Nilo; Canal, Cláudio Wageck; Makiejczuk, Aline; Allgayer, Mariangela da Costa; Cardoso, Cristine Hoffmeister; Lehmann, Fernanda Kieling; Fonseca, André Salvador Kazantzi; Lunge, Vagner Ricardo

    2013-12-01

    Canine distemper virus (CDV) is the cause of a severe and highly contagious disease in dogs. Practical diagnosis of canine distemper based on clinical signs and laboratory tests are required to confirm CDV infection. The present study aimed to develop a molecular assay to detect and differentiate field and vaccine CDV strains. Reverse transcription followed by nested real time polymerase chain reaction (RT-nqPCR) was developed, which exhibited analytical specificity (all the samples from healthy dogs and other canine infectious agents were not incorrectly detected) and sensitivity (all replicates of a vaccine strain were positive up to the 3125-fold dilution - 10(0.7) TCID50). RT-nqPCR was validated for CDV detection on different clinical samples (blood, urine, rectal and conjunctival swabs) of 103 animals suspected to have distemper. A total of 53 animals were found to be positive based on RT-nqPCR in at least one clinical sample. Blood resulted in more positive samples (50 out of 53, 94.3%), followed by urine (44/53, 83.0%), rectal (38/53, 71%) and conjunctival (27/53, 50.9%) swabs. A commercial immunochromatography (IC) assay had detected CDV in only 30 conjunctival samples of these positive dogs. Nucleoprotein (NC) gene sequencing of 25 samples demonstrated that 23 of them were closer to other Brazilian field strains and the remaining two to vaccine strains. A single nucleotide sequences difference, which creates an Msp I restriction enzyme digestion, was used to differentiate between field and vaccine CDV strains by restriction fragment length polymorphism (RFLP) analysis. The complete assay was more sensitive than was IC for the detection of CDV. Blood was the more frequently positive specimen and the addition of a restriction enzyme step allowed the differentiation of vaccine and Brazilian field strains.

  8. A Two-Stage Penalized Logistic Regression Approach to Case-Control Genome-Wide Association Studies

    Directory of Open Access Journals (Sweden)

    Jingyuan Zhao

    2012-01-01

    Full Text Available We propose a two-stage penalized logistic regression approach to case-control genome-wide association studies. This approach consists of a screening stage and a selection stage. In the screening stage, main-effect and interaction-effect features are screened by using L1-penalized logistic like-lihoods. In the selection stage, the retained features are ranked by the logistic likelihood with the smoothly clipped absolute deviation (SCAD penalty (Fan and Li, 2001 and Jeffrey’s Prior penalty (Firth, 1993, a sequence of nested candidate models are formed, and the models are assessed by a family of extended Bayesian information criteria (J. Chen and Z. Chen, 2008. The proposed approach is applied to the analysis of the prostate cancer data of the Cancer Genetic Markers of Susceptibility (CGEMS project in the National Cancer Institute, USA. Simulation studies are carried out to compare the approach with the pair-wise multiple testing approach (Marchini et al. 2005 and the LASSO-patternsearch algorithm (Shi et al. 2007.

  9. Maternal geohelminth infections are associated with an increased susceptibility to geohelminth infection in children: a case-control study.

    Directory of Open Access Journals (Sweden)

    Raaj S Mehta

    Full Text Available BACKGROUND: Children of mothers infected with soil-transmitted helminths (STH may have an increased susceptibility to STH infection. METHODS AND FINDINGS: We did a case-control study nested in a birth cohort in Ecuador. Data from 1,004 children aged 7 months to 3 years were analyzed. Cases were defined as children with Ascaris lumbricoides and/or Trichuris trichiura, controls without. Exposure was defined as maternal infection with A. lumbricoides and/or T. trichiura, detected during the third trimester of pregnancy. The analysis was restricted to households with a documented infection to control for infection risk. Children of mothers with STH infections had a greater risk of infection compared to children of uninfected mothers (adjusted OR 2.61, 95% CI: 1.88-3.63, p<0.001. This effect was particularly strong in children of mothers with both STH infections (adjusted OR: 5.91, 95% CI: 3.55-9.81, p<0.001. Newborns of infected mothers had greater levels of plasma IL-10 than those of uninfected mothers (p=0.033, and there was evidence that cord blood IL-10 was increased among newborns who became infected later in childhood (p=0.060. CONCLUSION: Our data suggest that maternal STH infections increase susceptibility to infection during early childhood, an effect that was associated with elevated IL-10 in cord plasma.

  10. A polytomous conditional likelihood approach for combining matched and unmatched case-control studies.

    Science.gov (United States)

    Gebregziabher, Mulugeta; Guimaraes, Paulo; Cozen, Wendy; Conti, David V

    2010-04-30

    In genetic association studies it is becoming increasingly imperative to have large sample sizes to identify and replicate genetic effects. To achieve these sample sizes, many research initiatives are encouraging the collaboration and combination of several existing matched and unmatched case-control studies. Thus, it is becoming more common to compare multiple sets of controls with the same case group or multiple case groups to validate or confirm a positive or negative finding. Usually, a naive approach of fitting separate models for each case-control comparison is used to make inference about disease-exposure association. But, this approach does not make use of all the observed data and hence could lead to inconsistent results. The problem is compounded when a common case group is used in each case-control comparison. An alternative to fitting separate models is to use a polytomous logistic model but, this model does not combine matched and unmatched case-control data. Thus, we propose a polytomous logistic regression approach based on a latent group indicator and a conditional likelihood to do a combined analysis of matched and unmatched case-control data. We use simulation studies to evaluate the performance of the proposed method and a case-control study of multiple myeloma and Inter-Leukin-6 as an example. Our results indicate that the proposed method leads to a more efficient homogeneity test and a pooled estimate with smaller standard error.

  11. A net clinical benefit analysis of warfarin and aspirin on stroke in patients with atrial fibrillation: a nested case–control study

    Directory of Open Access Journals (Sweden)

    Azoulay Laurent

    2012-06-01

    Full Text Available Abstract Background As the management of patients treated with anticoagulants and antiplatelet drugs entails balancing coagulation levels, we evaluated the net clinical benefit of warfarin and aspirin on stroke in a large cohort of patients with atrial fibrillation (AF. Methods A population-based cohort study of all patients at least 18 years of age with a first-ever diagnosis of chronic AF during the period 1993–2008 was conducted within the United Kingdom General Practice Research Database. A nested case–control analysis was conducted to estimate the risk of ischemic stroke and intracranial hemorrhage associated with the use of warfarin and aspirin. Cases were matched up to 10 controls on age, sex, and date of cohort entry. The adjusted net clinical benefit of warfarin and aspirin (expressed as the number of strokes prevented per 100 persons per year was calculated by subtracting the ischemic stroke rate (prevented by therapy from the intracranial hemorrhage (ICH rate (increased by therapy. Results The cohort included 70,766 patients newly-diagnosed with chronic AF, of whom 5519 experienced an ischemic stroke and 689 an ICH during follow-up. The adjusted net clinical benefit of warfarin was 0.59 (95% CI: 0.45, 0.73. However, the benefit was not seen for patients below (0.08, 95%: -0.38, 0.54 and above (−0.49, 95% CI: -1.13, 0.15 therapeutic range. The net clinical benefit of warfarin, apparent after 3 months of continuous use, increased as a function of CHADS2 score. The net clinical benefit was not significant with aspirin (−0.07, 95% CI: -0.22, 0.08, though it was seen in certain subgroups. Conclusions Warfarin provides a net clinical benefit in patients with atrial fibrillation, which is maintained with longer duration of use, particularly when used within therapeutic range. A similar net effect is not as clear with aspirin.

  12. Hodgkin's disease: case control epidemiological study in Yorkshire.

    Science.gov (United States)

    Bernard, S M; Cartwright, R A; Darwin, C M; Richards, I D; Roberts, B; O'Brien, C; Bird, C C

    1987-01-01

    This is the first report of a case-control epidemiological study on lymphomas and leukaemias occurring in Yorkshire during 1979-84. This paper deals with the results of the Hodgkin's disease analysis comprising 248 cases and 489 controls. The results indicate support for previous work with respect to small family size and past history of infectious mononucleosis. Positive observations made in a previous pilot study are also confirmed and extended with respect to associations with certain chronic skin lesions, dental anaesthesia and familial factors. Negative associations are described with respect to X-ray exposures and cigarette smoking. It is proposed that these results fit into a general hypothesis that these conditions are the result of interaction between infectious agents and altered immunity in those persons genetically predisposed.

  13. Associations between UCP1 -3826A/G, UCP2 -866G/A, Ala55Val and Ins/Del, and UCP3 -55C/T polymorphisms and susceptibility to type 2 diabetes mellitus: case-control study and meta-analysis.

    Directory of Open Access Journals (Sweden)

    Bianca M de Souza

    Full Text Available BACKGROUND: Some studies have reported associations between five uncoupling protein (UCP 1-3 polymorphisms and type 2 diabetes mellitus (T2DM. However, other studies have failed to confirm the associations. This paper describes a case-control study and a meta-analysis conducted to attempt to determine whether the following polymorphisms are associated with T2DM: -3826A/G (UCP1; -866G/A, Ala55Val and Ins/Del (UCP2 and -55C/T (UCP3. METHODS: The case-control study enrolled 981 T2DM patients and 534 nondiabetic subjects, all of European ancestry. A literature search was run to identify all studies that investigated associations between UCP1-3 polymorphisms and T2DM. Pooled odds ratios (OR were calculated for allele contrast, additive, recessive, dominant and co-dominant inheritance models. Sensitivity analyses were performed after stratification by ethnicity. RESULTS: In the case-control study the frequencies of the UCP polymorphisms did not differ significantly between T2DM and nondiabetic groups (P>0.05. Twenty-three studies were eligible for the meta-analysis. Meta-analysis results showed that the Ala55Val polymorphism was associated with T2DM under a dominant model (OR = 1.27, 95% CI 1.03-1.57; while the -55C/T polymorphism was associated with this disease in almost all genetic models: allele contrast (OR = 1.17, 95% CI 1.02-1.34, additive (OR = 1.32, 95% CI 1.01-1.72 and dominant (OR = 1.18, 95% CI 1.02-1.37. However, after stratification by ethnicity, the UCP2 55Val and UCP3 -55C/T alleles remained associated with T2DM only in Asians (OR = 1.25, 95% CI 1.02-1.51 and OR = 1.22, 95% CI 1.04-1.44, respectively; allele contrast model. No significant association of the -3826A/G, -866G/A and Ins/Del polymorphisms with T2DM was observed. CONCLUSIONS: In our case-control study of people with European ancestry we were not able to demonstrate any association between the UCP polymorphisms and T2DM; however, our meta-analysis detected a significant

  14. Leptospira Exposure and Gardeners: A Case-Control Seroprevalence Study

    Science.gov (United States)

    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

  15. 嵌套式斩波运放的分析与设计%Analysis and Design of Nested Chopper Operational Amplifier

    Institute of Scientific and Technical Information of China (English)

    张锗源; 杨发顺; 杨法明; 张荣芬; 邓朝勇

    2012-01-01

    A nested chopper operational amplifier was designed to solve the problem of large residual offset in traditional chopper amplifiers. Simulation with Spectre based on SMIC 0. 18 μm CMOS process showed that the circuit had an open loop gain of 78. 3 dB and a CMMR up to 112 dB. With chopper frequency /chophigh = 10 kHz and fchoplow=500 Hz, the single chopper and nested chopper opamp were simulated, respectively, using non-matched chopper switch. Results indicated that the nested chopper was helpful to reduce residual offset The nested chopper opamp is suitable for processing weak signal with low bandwidth, such as front-end readout circuit in sensors and audio signal amplifier circuit.%针对传统的斩波运放具有大残余失调的特点,设计了一个嵌套式斩波运放.基于SMIC0.18μm工艺,通过Spectre仿真工具进行验证与仿真,运放的开环增益达到78.3 dB,共模抑制比达到112 dB.在斩波频率fchophigh=10 kHz、fchoplow=500 Hz的条件下,通过使用非匹配斩波开关,分别对单斩波和嵌套式斩波运放进行仿真.结果表明,嵌套式斩波技术能有效减小残余失调的影响.适用于带宽较低的微弱信号检测与处理电路,如传感器前端读出电路和音频信号放大电路等.

  16. Nested PCR Detection and Phylogenetic Analysis of Babesia bovis and Babesia bigemina in Cattle from Peri-Urban Localities in Gauteng Province, South Africa

    OpenAIRE

    2013-01-01

    ABSTRACT Babesia bovis and Babesia bigemina are tick-borne hemoparasites causing babesiosis in cattle worldwide. This study was aimed at providing information about the occurrence and geographical distribution of B. bovis and B. bigemina species in cattle from Gauteng province, South Africa. A total of 268 blood samples collected from apparently healthy animals in 14 different peri-urban localities were tested using previously established nested PCR assays for the detection of B. bovis and B....

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

    Science.gov (United States)

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

    2017-03-07

    Glioma is a rare brain tumour with a very poor prognosis and the search for modifiable factors is intense. We reviewed the literature concerning risk factors for glioma obtained in case-control designed epidemiological studies in order to discuss the influence of this methodology on the observed results. When reviewing the association between three exposures, medical radiation, exogenous hormone use and allergy, we critically appraised the evidence from both case-control and cohort studies. For medical radiation and hormone replacement therapy (HRT), questionnaire-based case-control studies appeared to show an inverse association, whereas nested case-control and cohort studies showed no association. For allergies, the inverse association was observed irrespective of study design. We recommend that the questionnaire-based case-control design be placed lower in the hierarchy of studies for establishing cause-and-effect for diseases such as glioma. We suggest that a state-of-the-art case-control study should, as a minimum, be accompanied by extensive validation of the exposure assessment methods and the representativeness of the study sample with regard to the exposures of interest. Otherwise, such studies cannot be regarded as 'hypothesis testing' but only 'hypothesis generating'. We consider that this holds true for all questionnaire-based case-control studies on cancer and other chronic diseases, although perhaps not to the same extent for each exposure-outcome combination.British Journal of Cancer advance online publication, 7 March 2017; doi:10.1038/bjc.2017.46 www.bjcancer.com.

  18. Nested subgraphs of complex networks

    Energy Technology Data Exchange (ETDEWEB)

    Corominas-Murtra, Bernat; Sole, Ricard V [ICREA-Complex Systems Lab, Universitat Pompeu Fabra, Dr Aiguader 80, 08003 Barcelona (Spain); Mendes, Jose F F [Departamento de Fisica da Universidade de Aveiro, 3810-193 Aveiro (Portugal)], E-mail: bernat.corominas@upf.edu

    2008-09-26

    We analytically explore the scaling properties of a general class of nested subgraphs in complex networks, which includes the K-core and the K-scaffold, among others. We name such a class of subgraphs K-nested subgraphs since they generate families of subgraphs such that ...S{sub K+1}(G) subset or equal S{sub K}(G) subset or equal S{sub K-1}(G).... Using the so-called configuration model it is shown that any family of nested subgraphs over a network with diverging second moment and finite first moment has infinite elements (i.e. lacking a percolation threshold). Moreover, for a scale-free network with the above properties, we show that any nested family of subgraphs is self-similar by looking at the degree distribution. Both numerical simulations and real data are analyzed and display good agreement with our theoretical predictions.

  19. Structural relations between nested harmonic sums

    Energy Technology Data Exchange (ETDEWEB)

    Bluemlein, J.

    2008-07-15

    We describe the structural relations between nested harmonic sums emerging in the description of physical single scale quantities up to the 3-loop level in renormalizable gauge field theories. These are weight w=6 harmonic sums. We identify universal basic functions which allow to describe a large class of physical quantities and derive their complex analysis. For the 3-loop QCD Wilson coefficients 35 basic functions are required, whereas a subset of 15 describes the 3-loop anomalous dimensions. (orig.)

  20. Combined effect of tobacco smoking and alcohol drinking in the risk of head and neck cancers: a re-analysis of case-control studies using bi-dimensional spline models.

    Science.gov (United States)

    Dal Maso, Luigino; Torelli, Nicola; Biancotto, Elisa; Di Maso, Matteo; Gini, Andrea; Franchin, Gianni; Levi, Fabio; La Vecchia, Carlo; Serraino, Diego; Polesel, Jerry

    2016-04-01

    The synergistic effect of tobacco smoking and alcohol consumption on the risk of head and neck cancers has been mainly investigated as a cross-product of categorical exposure, thus leading to loss of information. We propose a bi-dimensional logistic spline model to investigate the interacting dose-response relationship of two continuous exposures (i.e., ethanol intake and tobacco smoking) on the risk of head and neck cancers, representing results through three-dimensional graphs. This model was applied to a pool of hospital-based case-control studies on head and neck cancers conducted in Italy and in the Vaud Swiss Canton between 1982 and 2000, including 1569 cases and 3147 controls. Among never drinkers and for all levels of ethanol intake, the risk of head and neck cancers steeply increased with increasing smoking intensity, starting from 1 cigarette/day. The risk associated to ethanol intake increased with incrementing exposure among smokers, and a threshold effect at approximately 50 g/day emerged among never smokers. Compared to abstainers from both tobacco and alcohol consumption, the combined exposure to ethanol and/or cigarettes led to a steep increase of cancer risk up to a 35-fold higher risk (95 % confidence interval 27.30-43.61) among people consuming 84 g/day of ethanol and 10 cigarettes/day. The highest risk was observed at the highest levels of alcohol and tobacco consumption. Our findings confirmed a combined effect of tobacco smoking and alcohol drinking on head and neck cancers risk, providing evidence that bi-dimensional spline models could be a feasible and flexible method to explore the pattern of risks associated to two interacting continuous-exposure variables.

  1. DIAMONDS: a new Bayesian nested sampling tool*

    Directory of Open Access Journals (Sweden)

    Corsaro Enrico

    2015-01-01

    Full Text Available In the context of high-quality asteroseismic data provided by the NASA Kepler Mission, we developed a new code, termed DIAMONDS (high-DImensional And multi-MOdal NesteD Sampling, for fast Bayesian parameter estimation and model comparison by means of the Nested Sampling Monte Carlo (NSMC algorithm, an efficient and powerful method very suitable for high-dimensional problems (like the peak bagging analysis of solar-like oscillations and multi-modal problems (i.e. problems that show multiple solutions. We applied the code to the peak bagging analysis of solar-like oscillations observed in a challenging F-type star. By means of DIAMONDS one is able to detect the different backgrounds in the power spectrum of the star (e.g. stellar granulation and faculae activity and to understand whether one or two oscillation peaks can be identified or not. In addition, we demonstrate a novel approach to peak bagging based on multi-modality, which is able to reduce significantly the number of free parameters involved in the peak bagging model. This novel approach is therefore of great interest for possible future automatization of the entire analysis technique.

  2. Multiple Sclerosis Associated Risk Factors: A Case-Control Study

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    Jalal POOROLAJAL

    2015-11-01

    Full Text Available Background: Hamadan Province is one of the high-risk regions in Iran for Multiple sclerosis (MS. A majority of the epidemiological studies conducted in Iran addressing MS are descriptive. This study was conducted to assess MS and its associated risk factors in Hamadan Province, the west of Iran.Methods: This case-control study compared 100 patients with MS (case group and 100 patients with acute infectious diseases (control group from September 2013 to March 2014. A checklist was used to assess the demographic, medical, and family history of the patients. The Friedman-Rosenman questionnaire was also used to assess personality type. Statistical analysis was performed using logistic regression model with Stata 11 software program.Results: The adjusted odds ratio (OR estimate of MS was 4.37 (95% CI: 2.33, 8.20 for females compared to males; 0.15 (95% CI: 0.06, 0.43 for people aged above 50 years compared to aged 14 to 29 years; 0.44 (95% CI: 0.21, 0.91 for overweight or obese people compared to normal weights. Crude OR indicated a significant association between the occurrence of MS and exclusive breast feeding, season of birth, and smoking. However, the association was not statistically significant after adjustment for other covariates.Conclusion: The risk of MS is significantly lower in male gender, obese/overweight, and old people. Furthermore, non-smoking, non-exclusive breast-feeding, and born in autumn may increase the risk of MS but need further investigation. However, long-term large prospective cohort studies are needed to investigate the true effect of the potential risk factors on MS. Keywords: Multiple sclerosis, Risk factors, Case-control study, Iran

  3. Hospital visitors as controls in case-control studies

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    Gulnar Azevedo S Mendonça

    2001-10-01

    Full Text Available OBJECTIVE: Selecting controls is one of the most difficult tasks in the design of case-control studies. Hospital controls may be inadequate and random controls drawn from the base population may be unavailable. The aim was to assess the use of hospital visitors as controls in a case-control study on the association of organochlorinated compounds and other risk factors for breast cancer conducted in the main hospital of the "Instituto Nacional de Câncer" -- INCA (National Cancer Institute in Rio de Janeiro (Brazil. METHODS: The study included 177 incident cases and 377 controls recruited among female visitors. Three different models of control group composition were compared: Model 1, with all selected visitors; Model 2, excluding women visiting relatives with breast cancer; and Model 3, excluding all women visiting relatives with any type of cancer. Odds ratios (OR and 95% confidence intervals were calculated to test the associations. RESULTS: Age-adjusted OR for breast cancer associated with risk factors other than family history of cancer, except smoking and breast size, were similar in the three models. Regarding family history of all cancers, except for breast cancer, there was a decreased risk in Models 1 and 2, while in Model 3 there was an increased risk, but not statistically significant. Family history of breast cancer was a risk factor in Models 2 and 3, but no association was found in Model 1. In multivariate analysis a significant risk of breast cancer was found when there was a family history of breast cancer in Models 2 and 3 but not in Model 1. CONCLUSIONS: These results indicate that while investigating risk factors unrelated to family history of cancer, the use of hospital visitors as controls may be a valid and feasible alternative.

  4. Diagnóstico e genotipagem do vírus da pseudoraiva por nested-PCR e análise de restrição enzimática Diagnosis and genotyping of pseudorabies virus by nested-PCR and restriction enzyme analysis

    Directory of Open Access Journals (Sweden)

    Antônio Augusto Fonseca Júnior

    2010-04-01

    virus isolation, DNA purification enzyme restriction analysis and a long electrophoresis. The aim of this research was to describe a faster and more sensitive method to detect and genotype PrV based on nested-PCR and restriction enzyme analysis. Twenty PrV isolates from south and southeast regions of Brazil, and the standard strain Shope were grown in PK-15 cells and submitted to PCR for glycoprotein E gene amplification. Additionally were tested 75 clinical samples (swine brain, with 25 positives for virus isolation and seroneutralization, and 50 negatives from a flock free PR with negative results in seroneutralization test. There was 100% of agreement between results of nested-PCR and virus isolation and seroneutralization and all samples detected were classified as genotype II. The nested-PCR, combined with restriction enzyme analysis, was able to detect and genotype PrV in 1-2 days with a sensitivity of 10-1,3 TCID50 mL-1. It was faster than classical methods described in the literature that require at least 7 days to be completed.

  5. Nest poaching in Neotropical parrots

    Science.gov (United States)

    Wright, T.F.; Toft, C.A.; Enkerlin-Hoeflich, E.; Gonzalez-Elizondo, J.; Albornoz, M.; Rodriguez-Ferraro, A.; Rojas-Suarez, F.; Sanz, V.; Trujillo, A.; Beissinger, S.R.; Berovides A., V.; Galvez A., X.; Brice, A.T.; Joyner, K.; Eberhard, J.; Gilardi, J.; Koenig, S.E.; Stoleson, S.; Martuscelli, P.; Meyers, J.M.; Renton, K.; Rodriguez, A.M.; Sosa-Asanza, A.C.; Vilella, F.J.; Wiley, J.W.

    2001-01-01

    Although the poaching of nestlings for the pet trade is thought to contribute to the decline of many species of parrots, its effects have been poorly demonstrated. We calculated rates of mortality due to nest poaching in 23 studies of Neotropical parrots, representing 4024 nesting attempts in 21 species and 14 countries. We also examined how poaching rates vary with geographic region, presence of active protection programs, conservation status and economic value of a species, and passage of the U.S. Wild Bird Conservation Act. The average poaching rate across all studies was 30% of all nests observed. Thirteen studies reported poaching rates of >20%, and four reported rates of >70%. Only six studies documented no nest poaching. Of these, four were conducted on islands in the Caribbean region, which had significantly lower poaching rates than the mainland Neotropics. The other two studies that showed no poaching were conducted on the two species with the lowest economic value in our sample (U.S. retail price). In four studies that allowed direct comparison between poaching at sites with active nest protection versus that at unprotected sites, poaching rates were significantly lower at protected sites, suggesting that active protection efforts can be effective in reducing nest poaching. In those studies conducted both before and after the passage of the U.S. Wild Bird Conservation Act, poaching rates were found to be significantly lower following its enactment than in the period before. This result supports the hypothesis that the legal and illegal parrot trades are positively related, rather than inversely related as has been suggested by avicultural interests. Overall, our study indicates that poaching of parrot nestlings for economic gain is a widespread and biologically significant source of nest mortality in Neotropical parrots.

  6. Broadband DOA Estimation Based on Nested Arrays

    Directory of Open Access Journals (Sweden)

    Zhi-bo Shen

    2015-01-01

    Full Text Available Direction of arrival (DOA estimation is a crucial problem in electronic reconnaissance. A novel broadband DOA estimation method utilizing nested arrays is devised in this paper, which is capable of estimating the frequencies and DOAs of multiple narrowband signals in broadbands, even though they may have different carrier frequencies. The proposed method converts the DOA estimation of multiple signals with different frequencies into the spatial frequency estimation. Then, the DOAs and frequencies are pair matched by sparse recovery. It is possible to significantly increase the degrees of freedom (DOF with the nested arrays and the number of sources can be more than that of sensor array. In addition, the method can achieve high estimation precision without the two-dimensional search process in frequency and angle domain. The validity of the proposed method is verified by theoretic analysis and simulation results.

  7. Complete Mapping of a Cystine Knot and Nested Disulfides of Recombinant Human Arylsulfatase A by Multi-Enzyme Digestion and LC-MS Analysis Using CID and ETD

    Science.gov (United States)

    Ni, Wenqin; Lin, Melanie; Salinas, Paul; Savickas, Philip; Wu, Shiaw-Lin; Karger, Barry L.

    2013-01-01

    Cystine knots or nested disulfides are structurally difficult to characterize, despite current technological advances in peptide mapping with high-resolution liquid chromatography coupled with mass spectrometry (LC-MS). In the case of recombinant human arylsulfatase A (rhASA), there is one cystine knot at the C-terminal, a pair of nested disulfides at the middle, and two out of three unpaired cysteines in the N-terminal region. The statuses of these cysteines are critical structure attributes for rhASA function and stability that requires precise examination. We used a unique approach to determine the status and linkage of each cysteine in rhASA, which was comprised of multi-enzyme digestion strategies (from Lys-C, trypsin, Asp-N, pepsin, and PNGase F) and multi-fragmentation methods in mass spectrometry using electron transfer dissociation (ETD), collision induced dissociation (CID), and CID with MS3 (after ETD). In addition to generating desired lengths of enzymatic peptides for effective fragmentation, the digestion pH was optimized to minimize the disulfide scrambling. The disulfide linkages, including the cystine knot and a pair of nested cysteines, unpaired cysteines, and the post-translational modification of a cysteine to formylglycine, were all determined. In the assignment, the disulfide linkages were Cys138-Cys154, Cys143-Cys150, Cys282-Cys396, Cys470-Cys482, Cys471-Cys484, and Cys475-Cys481. For the unpaired cysteines, Cys20 and Cys276 were free cysteines, and Cys51 was largely converted to formylglycine (>70 %). A successful methodology has been developed, which can be routinely used to determine these difficult-to-resolve disulfide linkages, ensuring drug function and stability.

  8. Successful nesting behavior of Puerto Rican parrots

    Science.gov (United States)

    Wilson, K.A.; Field, R.; Wilson, M.H.

    1995-01-01

    We analyzed nesting behavior of five pairs of the endangered Puerto Rican Parrot (Amazona vittata) during eight successful nesting attempts. Each stage of the nesting cycle (egg laying, incubation, early chick rearing, and late chick rearing) was characterized by distinct trends or levels of behavior. During egg laying, female attentiveness to tile nest increased, and male attentiveness decreased. Throughout incubation and the first several days of early chick rearing, females were highly attentive to their nests, whereas males rarely entered the nest cavities. Female attentiveness then began to decline. Male attentiveness to the nest was sporadic until chicks were 10-12 days old. when all males began to enter their nests at least once each day. During late chick rearing, both male and female attentiveness were erratic and highly variable. Biologists may be able to use these results to identify nest problems and the need for management intervention when patterns of nest attentiveness deviate from the limits described in this study..

  9. Association between diabetes and tuberculosis: case-control study

    Science.gov (United States)

    Pereira, Susan Martins; de Araújo, Gleide Santos; Santos, Carlos Antônio de Souza Teles; de Oliveira, Maeli Gomes; Barreto, Maurício Lima

    2016-01-01

    ABSTRACT OBJECTIVE To test the association between diabetes and tuberculosis. METHODS It is a case-control study, matched by age and sex. We included 323 new cases of tuberculosis with positive results for bacilloscopy. The controls were 323 respiratory symptomatic patients with negative bacilloscopy, from the same health services, such as: ambulatory cases from three referral hospitals and six basic health units responsible for the notifications of new cases of tuberculosis in Salvador, Bahia. Data collection occurred between 2008 and 2010. The instruments used were structured interview, including clinical data, capillary blood glucose (during fasting or postprandial), and the CAGE questionnaire for screening of abusive consumption of alcohol. Descriptive, exploratory, and multivariate analysis was performed using conditional logistic regression. RESULTS The average age of the cases was 38.5 (SD = 14.2) years and of the controls, 38.5 (SD = 14.3) years. Among cases and controls, most subjects (61%) were male. In univariate analysis we found association between the occurrence of diabetes and tuberculosis (OR = 2.37; 95%CI 1.04–5.42), which remained statistically significant after adjustment for potential confounders (OR = 3.12; 95%CI 1.12–7.94). CONCLUSIONS The association between diabetes and tuberculosis can hinder the control of tuberculosis, contributing to the maintainance of the disease burden. The situation demands increasing early detection of diabetes among people with tuberculosis, in an attempt to improve disease control strategies. PMID:28099656

  10. Nutrient patterns and asthenozoospermia: a case-control study.

    Science.gov (United States)

    Eslamian, G; Amirjannati, N; Rashidkhani, B; Sadeghi, M-R; Hekmatdoost, A

    2017-04-01

    The association of dietary nutrient patterns and sperm motility is not yet well elucidated, and previous studies have just focused on the isolated nutrients. This case-control study examined the association of nutrient patterns with asthenozoospermia among Iranian men. In total, 107 incident asthenozoospermic men and 235 age-matched controls were interviewed through the infertility clinics in Tehran, Iran, from January 2012 to November 2013. Semen quality data were analysed according to the fifth edition of WHO guideline. Nutrient patterns were identified using principal component analysis based on semiquantitative 168-item food frequency questionnaires. All nutrient intakes were energy-adjusted by the residual method. In principal component analysis, three dietary patterns emerged. The first pattern, which was high in vitamin E, vitamin D, vitamin C, zinc, folate, total fibre, selenium and polyunsaturated fatty acids, was significantly associated with lower risk of asthenozoospermia. After adjustment for potential confounders, participants in the highest tertile of the first pattern scores had 51% lower risk of asthenozoospermia compared with those in the lowest (p-trend: .004). Our findings suggest that adherence to the pattern comprising mainly of antioxidant nutrients may be inversely associated with asthenozoospermia.

  11. Association between diabetes and tuberculosis: case-control study

    Directory of Open Access Journals (Sweden)

    Susan Martins Pereira

    Full Text Available ABSTRACT OBJECTIVE To test the association between diabetes and tuberculosis. METHODS It is a case-control study, matched by age and sex. We included 323 new cases of tuberculosis with positive results for bacilloscopy. The controls were 323 respiratory symptomatic patients with negative bacilloscopy, from the same health services, such as: ambulatory cases from three referral hospitals and six basic health units responsible for the notifications of new cases of tuberculosis in Salvador, Bahia. Data collection occurred between 2008 and 2010. The instruments used were structured interview, including clinical data, capillary blood glucose (during fasting or postprandial, and the CAGE questionnaire for screening of abusive consumption of alcohol. Descriptive, exploratory, and multivariate analysis was performed using conditional logistic regression. RESULTS The average age of the cases was 38.5 (SD = 14.2 years and of the controls, 38.5 (SD = 14.3 years. Among cases and controls, most subjects (61% were male. In univariate analysis we found association between the occurrence of diabetes and tuberculosis (OR = 2.37; 95%CI 1.04–5.42, which remained statistically significant after adjustment for potential confounders (OR = 3.12; 95%CI 1.12–7.94. CONCLUSIONS The association between diabetes and tuberculosis can hinder the control of tuberculosis, contributing to the maintainance of the disease burden. The situation demands increasing early detection of diabetes among people with tuberculosis, in an attempt to improve disease control strategies.

  12. Risk Factors For Ectopic Pregnancy : A Case Control Study

    Directory of Open Access Journals (Sweden)

    Deshmukh J.S

    1999-01-01

    Full Text Available Research question: Which are the risk factors for ectopic pregnancy . Objective: To study the strength of association between hypothesised risk factors and ectopic pregnancy. Study design: Unmatched case- control study. Setting: Government Medical College, Hospital, Nagpur. Participants: 133 cases of ectopic pregnancy and equal number of controls (non pregnant women admitted to study hospital. Study variables : Pelvic inflammatory diseases, sexually transmitted diseases, IUD use at conception , past use of IUD, prior ectopic pregnancy, OC pills use at the time of conception, past use of OC pills, induced abortion, spontaneous abortion, infertility and pelvic and abdominal surgery. Statistical analysis: Odds ratios & their 95% CI, Pearson’s chi square test, unconditional logistic regression analysis and population attributable risk proportion. Results : Use of IUD at conception, prior ectopic pregnancy , pelvic inflammatory disease, sexually transmitted diseases, infertility, OC pills use at the time of conception, past use of IUD and induced abortion were found to be significantly associated with ectopic pregnancy. Conclusion: Identification of these risk factors for etopic pregnancy shall help in early detection and appropriate management in an individual case and it may help in devising a comprehensive preventive strategy for ectopic pregnancy

  13. Nested Dynamic Condition Response Graphs

    DEFF Research Database (Denmark)

    Hildebrandt, Thomas; Mukkamala, Raghava Rao; Slaats, Tijs

    2012-01-01

    We present an extension of the recently introduced declarative process model Dynamic Condition Response Graphs ( DCR Graphs) to allow nested subgraphs and a new milestone relation between events. The extension was developed during a case study carried out jointly with our industrial partner...... Exformatics, a danish provider of case and workflow management systems. We formalize the semantics by giving first a map from Nested to (flat) DCR Graphs with milestones, and then extending the previously given mapping from DCR Graphs to Buchi-automata to include the milestone relation....

  14. Impact of Urate Level on Cardiovascular Risk in Allopurinol Treated Patients. A Nested Case-Control Study

    DEFF Research Database (Denmark)

    Søltoft Larsen, Kasper; Pottegård, Anton; Lindegaard, Hanne M;

    2016-01-01

    BACKGROUND: Gout gives rise to increased risk of cardiovascular events. Gout attacks can be effectively prevented with urate lowering drugs, and allopurinol potentially reduces cardiovascular risk. What target level of urate is required to reduce cardiovascular risk is not known. OBJECTIVES...

  15. Oral bisphosphonates do not increase the risk of severe upper gastrointestinal complications: A nested case-control study

    NARCIS (Netherlands)

    A. Ghirardi (Arianna); L. Scotti (Lorenza); G.D. Vedova (Gianluca); L.C. D'Oro (Luca); F. Lapi (Francesco); F. Cipriani (Francesco); A.P. Caputi (Achille); A. Vaccheri (Alberto); D Gregori (Dario); R. Gesuita (Rosaria); A. Vestri (Annarita); T. Staniscia (Tommaso); G. Mazzaglia (Giampiero); G. Corrao (Giovanni); E. Sessa (E.); V. Arcoraci (Vincenzo); A. Parodi (Andrea); A. Zambon (A.); N. Montanaro (N.); C. Piccinni (C.); C. Suzzi (C.); A. Puccini (A.); M.C.J.M. Sturkenboom (Miriam); P. Geppetti (P.); L. Sati (L.); M. Di Bari (M.); F. Forlan (F.); F. Carle (F.); A. Menna (A.); R. Valenti (Renato)

    2014-01-01

    textabstractBackground: Data on the effect of oral bisphosphonates (BPs) on risk of upper gastrointestinal complications (UGIC) are conflicting. We conducted a large population-based study from a network of Italian healthcare utilization databases aimed to assess the UGIC risk associated with use of

  16. Long-term psychosocial sequelae of stillbirth: phase II of a nested case-control cohort study.

    Science.gov (United States)

    Turton, Penelope; Evans, Chris; Hughes, Patricia

    2009-02-01

    Stillbirth is associated with increased psychological morbidity in the subsequent pregnancy and puerperium. This study aimed to assess longer-term psychological and social outcomes of stillbirth and to identify factors associated with adverse outcome. We conducted seven-year follow-up of a cohort of women who were initially assessed during and after a pregnancy subsequent to stillbirth, together with pair-matched controls. All women were living with a partner at baseline and none had live children. Measured outcomes at follow-up included depression, posttraumatic stress disorder (PTSD) and partnership breakdown. Comparison variables included social and psychological factors and, for the stillbirth group, factors relating to the lost pregnancy. There were no differences between groups in case level psychological morbidity, but significantly higher levels of PTSD symptoms persisted in stillbirth group mothers who had case level PTSD 7 years earlier. Stillbirth group mothers were more likely to have experienced subsequent partnership breakdown. In the stillbirth group such breakdown was associated with having held the stillborn infant and having had case-level PTSD. Interpretations and clinical implications of these findings are discussed.

  17. A nested case-control study of the risk of suicide attempts after discharge from psychiatric care

    DEFF Research Database (Denmark)

    Christiansen, Erik; Jensen, Børge

    2008-01-01

    abuse with mental illness raised risk in an additive way. We found only small gender differences in risk. In order to lower the risk of suicide attempts, we need to improve after-care when discharging from psychiatric care. A differentiation between the possibilities of after-care for different mental...

  18. Prodromal symptoms and early detection of Parkinson's disease in general practice: a nested case-control study

    NARCIS (Netherlands)

    Plouvier, A.O.A.; Hameleers, R.J.M.G.; Heuvel, E.A. van den; Bor, H.H.; Olde Hartman, T.C.; Bloem, B.R.; Weel, C. van; Lagro-Janssen, A.

    2014-01-01

    BACKGROUND: Timely diagnosis of Parkinson's disease (PD), facilitating early intervention, depends largely on the GP's awareness of early symptomatology. For general practice, it is unknown which prodromal symptoms (symptoms preceding the typical motor symptoms of PD) demand the GP's alertness. OBJE

  19. The plasma leptin/adiponectin ratio predicts first cardiovascular event in men : A prospective nested case-control study

    NARCIS (Netherlands)

    Kappelle, Paul J.W.H.; Dullaart, Robin P. F.; van Beek, Andre P.; Hillege, Hans L.; Wolffenbuttel, Bruce H. R.

    2012-01-01

    Objective: The plasma leptin/adiponectin (L/A) ratio has been proposed as a preferential marker of atherosclerosis susceptibility compared to leptin and adiponectin alone. We determined the extent to which the L/A ratio predicts incident cardiovascular disease (CVD) taking account of clinical risk f

  20. Viremia during pregnancy and risk of childhood leukemia and lymphomas in the offspring: Nested case-control study.

    Science.gov (United States)

    Bzhalava, Davit; Hultin, Emilie; Arroyo Mühr, Laila Sara; Ekström, Johanna; Lehtinen, Matti; de Villiers, Ethel-Michele; Dillner, Joakim

    2016-05-01

    A possible role for infections of the pregnant mother in the development of childhood acute leukemias and lymphomas has been suggested. However, no specific infectious agent has been identified. Offspring of 74,000 mothers who had serum samples taken during pregnancy and stored in a large-scale biobank were followed up to the age of 15 years (750,000 person years) through over-generation linkages between the biobank files, the Swedish national population and cancer registers to identify incident leukemia/lymphoma cases in the offspring. First-trimester sera from mothers of 47 cases and 47 matched controls were retrieved and analyzed using next generation sequencing. Anelloviruses were the most common viruses detected, found in 37/47 cases and in 40/47 controls, respectively (OR: 0.6, 95% CI: 0.2-1.9). None of the detected viruses was associated with leukemia/lymphoma in the offspring. Viremia during pregnancy was common, but no association with leukemia/lymphoma risk in the offspring was found.

  1. Nested Narratives Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Andrew T. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Pattengale, Nicholas D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Forsythe, James C. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Carvey, Bradley John [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-02-01

    In cybersecurity forensics and incident response, the story of what has happened is the most important artifact yet the one least supported by tools and techniques. Existing tools focus on gathering and manipulating low-level data to allow an analyst to investigate exactly what happened on a host system or a network. Higher-level analysis is usually left to whatever ad hoc tools and techniques an individual may have developed. We discuss visual representations of narrative in the context of cybersecurity incidents with an eye toward multi-scale illustration of actions and actors. We envision that this representation could smoothly encompass individual packets on a wire at the lowest level and nation-state-level actors at the highest. We present progress to date, discuss the impact of technical risk on this project and highlight opportunities for future work.

  2. Nested Narratives Final Report.

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Andrew T.; Pattengale, Nicholas D.; Forsythe, James C.; Carvey, Bradley John

    2015-02-01

    In cybersecurity forensics and incident response, the story of what has happened is the most impor- tant artifact yet the one least supported by tools and techniques. Existing tools focus on gathering and manipulating low-level data to allow an analyst to investigate exactly what happened on a host system or a network. Higher-level analysis is usually left to whatever ad hoc tools and techniques an individual may have developed. We discuss visual representations of narrative in the context of cybersecurity incidents with an eye toward multi-scale illustration of actions and actors. We envision that this representation could smoothly encompass individual packets on a wire at the lowest level and nation-state-level actors at the highest. We present progress to date, discuss the impact of technical risk on this project and highlight opportunities for future work.

  3. Nest Survival of American Coots Relative to Grazing, Burning, and Water Depths

    Directory of Open Access Journals (Sweden)

    Jane E. Austin

    2011-12-01

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

  4. Instantiation Schemes for Nested Theories

    CERN Document Server

    Echenim, Mnacho

    2011-01-01

    This paper investigates under which conditions instantiation-based proof procedures can be combined in a nested way, in order to mechanically construct new instantiation procedures for richer theories. Interesting applications in the field of verification are emphasized, particularly for handling extensions of the theory of arrays.

  5. Application of nested sampling in statistical physics: the Potts model

    CERN Document Server

    Pfeifenberger, Manuel J

    2016-01-01

    We present a systematic benchmark study of the nested sampling algorithm on the basis of the Potts model. This model exhibits a first order phase transition for $q>4$ at the critical temperature. The numerical evaluation of the partition function and thermodynamic observables, which involves high dimensional sums of sharply structured multi-modal density functions, represents a major challenge to most standard numerical techniques, such as Markov Chain Monte Carlo. Nested sampling, on the other hand, is particularly suited for such problems. In this paper we will employ both, nested sampling and thermodynamic integration to evaluate the partition function of the Potts model. In both cases individual moves are based on Swendsen-Wang updates. A autocorrelation time analysis of both algorithms shows that the severe slowing down of thermodynamic integration around the critical temperature does not occur in nested sampling. In addition we show, how thermodynamic variables can be computed with high accuracy from th...

  6. Unusual raptor nests around the world

    Science.gov (United States)

    Ellis, D.H.; Craig, T.; Craig, E.; Postupalsky, S.; LaRue, C.T.; Nelson, R.W.; Anderson, D.W.; Henny, C.J.; Watson, J.; Millsap, B.A.; Dawson, J.W.; Cole, K.L.; Martin, E.M.; Margalida, A.; Kung, P.

    2009-01-01

    From surveys in many countries, we report raptors using unusual nesting materials (e.g., paper money, rags, metal, antlers, and large bones) and unusual nesting situations. For example, we documented nests of Steppe Eagles Aquila nipalensis and Upland Buzzards Buteo hemilasius on the ground beside well-traveled roads, Saker Falcon Falco cherrug eyries in attics and a cistern, and Osprey Pandion haliaetus nests on the masts of boats and on a suspended automobile. Other records include a Golden Eagle A. chrysaetos nest 7.0 m in height, believed to be the tallest nest ever described, and, for the same species, we report nesting in rudimentary nests. Some nest sites are within a few meters of known predators or competitors. These unusual observations may be important in revealing the plasticity of a species' behavioral repertoire. ?? 2009 The Raptor Research Foundation, Inc.

  7. Patterns of magpie nest utilization by a nesting raptor community in a secondary forest

    Institute of Scientific and Technical Information of China (English)

    Tong Zhou; Haitao Wang; Yu Liu; Fumin Lei; Wei Gao

    2009-01-01

    For a total of 9 years, we examined the patterns of a nesting raptor community that utilized European Magpie (Pica pica) nests in the Zuojia Natural Reserve, northeast China. Eight raptor species and two other bird species were recorded nesting in magpie nests. The reuse rate of abandoned magpie nests was 51.6%, and the number of reused nests was positively correlated with their availability. Raptors utilized 83.3% of the reused abandoned magpie nests. Nests followed for more than 1 year were reused by raptors an average of 1.13 times. Inter-specific nest usurpation was common, with 17.3% of new magpie nests being usurped by raptors, and four cases of usurpation occurred among different raptor species. At the community level, 8 of 11 raptor species took over magpie nests to breed in the study area, and 91.9% of their nests came from magpie nests. European Magpies represent the core species in the nest web of the local raptor community that utilizes magpie nests. At the forest stand level, closer proximity to forest edges and greater distances from occupied raptor nests were the best predictors of nest reuse. At the nest-site level, arbor density and canopy coverage were the best predictors of nest reuse.

  8. Periodontal disease and spontaneous preterm birth: a case control study

    Directory of Open Access Journals (Sweden)

    Eley Barry

    2006-07-01

    Full Text Available Abstract Background Several studies have suggested an association between periodontal disease and prematurity but this finding has not been consistently observed. Methods Case control study. Cases (n = 50 were women who had delivered after spontaneous preterm labor at Results There was no difference in the proportion of sites with significant attachment loss (≥3 mm: Cases-3.2%, Controls-2.2% p = 0.21. The gingival crevicular fluid concentrations of elastase and gingipain were elevated in cases vs. controls 238.8 uU/ul vs. 159.6 uU/ul p = .007 and 2.70 uU/ul vs. 1.56 uU/ul p = .001. On multivariate analysis, the mean log concentration of elastase, but not of gingipain, remained a significant predictor of preterm labor p = .0.015. Conclusion We found no evidence that clinical periodontal disease is associated with spontaneous preterm birth. Elevated gingival crevicular fluid levels of elastase were associated with preterm birth but further research is needed before this can be assumed to be a causal relationship.

  9. Violence against Women and Gastroschisis: A Case-Control Study

    Directory of Open Access Journals (Sweden)

    Daniel Ruiz

    2013-10-01

    Full Text Available Background: Gastroschisis, a birth defect characterized by herniated fetal abdominal wall, occurs more commonly in infants born to teenage and young mothers. Ischemia of the vascular vitelline vessels is the likely mechanism of pathogenesis. Given that chronic stress and violence against women are risk factors for cardiovascular disease we explored whether these may represent risk factors for gastroschisis, when they occur during pregnancy. A case-control study was conducted, with 15 incident cases of children born with gastroschisis in the Region of Murcia, Spain, from December 2007 to June 2013. Forty concurrent controls were recruited at gestation weeks 20–24 or post-partum. All mothers of cases and controls completed a comprehensive, in-person, ‘green sheet’ questionnaire on environmental exposures. Results: Mothers of children with gastroschisis were younger, smoked more cigarettes per week relative to controls, were exposed to higher amounts of illegal drugs, and suffered from domestic violence more frequently than the controls. Multivariable logistic regression analysis highlights periconceptional ‘gender-related violence’ (OR: 16.6, 95% CI 2.7 to 101.7 and younger maternal age (OR 1.1, 95% CI 1.0–1.3. Conclusions: Violence against pregnant women is associated with birth defects, and should be studied in more depth as a cause-effect teratogenic. Psychosocial risk factors, including gender-based violence, are important for insuring the health and safety of the pregnant mother and the fetus.

  10. Development with age of nest box use and gregarious nesting in laying hens

    DEFF Research Database (Denmark)

    Riber, Anja Brinch

    2010-01-01

    Use of nest boxes is an important part of the behavioural repertoire of laying hens kept under commercial conditions. A special form of nest box use is gregarious nesting, which occurs when a hen given the choice between an occupied and an unoccupied nest site chooses the occupied nest site...... experiences in selection of nest locations, causing the found decrease in frequency of gregarious nesting after age 20 weeks. A general preference for corner and end nest boxes is suggested to have triggered the initial use of the left nest box by the first hens coming into lay and to have maintained...... risk of broken or dirty eggs. The main objectives were to investigate the use of nest boxes according to their position and the occurrence of gregarious nesting with age. Twelve groups of 15 Isa Warren hens were housed in pens each containing three adjacent roll-out nest boxes only differing...

  11. Utilização de estratificação e modelo de regressão logística na análise de dados de estudos caso-controle Using of stratification and the logistic regression model in the analysis of data of case-control studies

    Directory of Open Access Journals (Sweden)

    Suely Godoy Agostinho Gimeno

    1995-08-01

    Full Text Available Exemplifica-se a aplicação de análise multivariada, por estratificação e com regressão logística, utilizando dados de um estudo caso-controle sobre câncer de esôfago. Oitenta e cinco casos e 292 controles foram classificados segundo sexo, idade e os hábitos de beber e de fumar. As estimativas por ponto dos odds ratios foram semelhantes, sendo as duas técnicas consideradas complementares.Data of a case-control study of esophageal cancer were used as an example of the use of multivariate analysis with stratification and logistic regression. Eighty-five cases and 292 controls were classified according to sex, age and smoking and drinking habits. The point estimates of the odds ratios were similar, and the techniques were considered complementary.

  12. Risk factors of Cancer Prostate A case control study.

    Science.gov (United States)

    Kamel, Nahed M; Tayel, Eiman S; El Abbady, Ahmed A; Khashab, Sahar S

    2006-01-01

    The purpose of this study is to reveal the different risk factors related to this cancer particularly that there is no agreement about which factors affect the risk. A fishing expedition hospital based case control study was carried out. Cases and controls were identified from the Urology Department of Alexandria Main University Hospital, 2004. All cases diagnosed as having the tumor were included in the case series. For each case the second subject proved to have a negative pathological examination was included in the control group (50).Data collection was carried out blindly using a structured interview schedule. Analysis was applied using Chi-square test, Fisher exact and Student's t-test. Odds Ratios and 95% Confidence Intervals were calculated. Results indicated that regular consumption of sausages was greater among cases than controls (X(2)= 10.19, p= 0.001 and an odds ratio of 5.92 (CI: 1.69-25.99). Also more cases claimed consuming regularly butter and natural ghee than controls (X(2)= 5.47, p= 0.019). The estimate risk was as high as 2.79 (Cl: 1.07-7.33). However regular consumption of vegetables was more encountered among controls than cases (X(2) = 5.005, p= 0.025 where the odds ratio was 0.19 (Cl: 0.02-1.01). Moreover the multiple regression analysis confirmed the results obtained from univariate analysis. The consistency of results of current work as regards sausages and butter with several other research works can support the identification of these specific possible risk factors. Also other research workers pointed out to the protective effect of vegetables. However further research is needed to address other risk factors.

  13. 社区空巢老人心理弹性特征的潜在类别分析%Latent class analysis on resilience characteristics of empty-nest elderly in community

    Institute of Scientific and Technical Information of China (English)

    张杰; 张静平; 王安妮; 苏盼

    2016-01-01

    目的 采用探索性潜在类别分析的方法对社区空巢老人心理弹性的特征进行分析,为不同特征群体实施针对性的干预措施提供依据.方法 采用问卷调查法,使用自编空巢老人一般资料调查表、Connor和Davidson心理弹性量表(CD-RISC)中文版对203名社区空巢老人进行调查,利用统计软件Mplus7.0对心理弹性的特征进行探索性潜在类别分析.结果 通过分析发现,社区空巢老人的心理弹性状况具有明显的分组特征,统计指标(AIC,BIC,Entropy等)支持了3个潜在类别的模型(P=0.006),根据每个类别在问卷各个条目上的条件概率,分别命名为高弹性组[54例(26.6%)],低耐压弹性组[82例(40.4%)],低弹性组[67例(33.0%)].进一步的研究发现:高弹性组与低弹性组类别中空巢老人在年龄构成上差异有统计学意义(P.<0.05),低耐压弹性组与低弹性组类别中的空巢老人在性别构成比例上差异有统计学意义(P<0.05).结论 社区空巢老人的心理弹性特征可分为3个类别,各类别的性别、年龄所占的比例不同.%Objective To analyze the characteristics of resilience among empty-nest elderly in community with exploratory latent class analysis method and provide a basis for making targeted intervention measures according to different characteristics.Methods This study enrolled 203 empty-nest elderly people as the study respondents.The general information,resilience of empty-nest elderly were investigated using the general information questionnaire,Connor-Davidson resilience scale in Chinese version.Latent class analyze (Mplus 7.0) was used to discuss the characteristics of resilience among empty-nest elderly.Results The results showed that the resilience of empty-nest elderly had obvious group characteristics and the statistical indicators(AIC,BIC,Entropy and so on) can support the three categories of potential model(P=0.006).Based on the conditional probability on the various

  14. No relationship between TNF-α genetic variants and combination antiretroviral therapy-related lipodystrophy syndrome in HIV type 1-infected patients: a case-control study and a meta-analysis.

    Science.gov (United States)

    Veloso, Sergi; Olona, Montserrat; Peraire, Joaquim; Viladés, Consuelo; Pardo, Pedro; Domingo, Pere; Asensi, Victor; Broch, Montserrat; Aguilar, Carmen; López-Dupla, Miguel; Aragonés, Gerard; Garcia-Pardo, Graciano; Sirvent, Joan-Josep; Vendrell, Joan; Richart, Cristóbal; Vidal, Francesc

    2011-02-01

    Tumor necrosis factor alpha (TNF-α) is thought to be involved in the pathogenic and metabolic events associated with HIV-1 infection. We assessed whether carriage of the TNF-α gene promoter single nucleotide polymorphism (SNP) is associated with lipodystrophy and metabolic derangements in HIV-1-infected patients treated with cART. We also assessed variations in TNF-α receptor plasma levels. The study group comprised 286 HIV-1-infected patients (133 with and 153 without lipodystrophy) and 203 uninfected controls (UC). TNF-α -238G > A, -308G > A, and -863 C > A SNP were assessed using PCR-RFLPs on white cell DNA. Plasma sTNF-α R1 and R2 levels were measured by ELISA. Student's t test, the χ(2) test, Pearson correlations, and the logistic regression test were performed for statistical analysis. The TNF-α -308G > A SNP was significantly associated with lipodystrophy in the univariate analysis (p = 0.04). This association, however, was no longer significant in the multivariate analysis. A meta-analysis of the published literature and our own data, which included 284 patients with lipodystrophy and 338 without lipodystrophy, showed that there was no relationship between the TNF-α -238G > A and -308G > A SNP and lipodystrophy (p > 0.05 for all comparisons). HIV-1-infected patients had greater sTNF-α R2 plasma levels than UC (p = 0.001) whereas sTNF-α R1 and R2 levels were not significantly different in both the HIV-1-infected cohorts, lipodystrophy vs. nonlipodystrophy (p = NS). In our cohort of white Spaniards the TNF-α -238G > A, -308G > A, and -863C > A SNP were not associated with lipodystrophy in HIV-1-infected patients treated with cART. This finding was replicated in a meta-analysis of the published data, which showed no associations between the TNF-α -238G > A and -308G > A SNP and lipodystrophy. In HIV-1-infected patients under cART there is a systemic overproduction of sTNF-α R2, which is unrelated to

  15. Importance Nested Sampling and the MultiNest Algorithm

    CERN Document Server

    Feroz, F; Cameron, E; Pettitt, A N

    2013-01-01

    Bayesian inference involves two main computational challenges. First, in estimating the parameters of some model for the data, the posterior distribution may well be highly multi-modal: a regime in which the convergence to stationarity of traditional Markov Chain Monte Carlo (MCMC) techniques becomes incredibly slow. Second, in selecting between a set of competing models the necessary estimation of the Bayesian evidence for each is, by definition, a (possibly high-dimensional) integration over the entire parameter space; again this can be a daunting computational task, although new Monte Carlo (MC) integration algorithms offer solutions of ever increasing efficiency. Nested sampling (NS) is one such contemporary MC strategy targeted at calculation of the Bayesian evidence, but which also enables posterior inference as a by-product, thereby allowing simultaneous parameter estimation and model selection. The widely-used MultiNest algorithm presents a particularly efficient implementation of the NS technique for...

  16. Influence of Habitat Types on Prairie Nesting Waterfowl Nest Density and Nest Success in Northeastern North Dakota, 2010 – 2013

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Nest density and nest success of ducks in native and non-native grasslands within the Devils Lake WMD, Northeastern North Dakota. Waterfowl representing 8 species of...

  17. Residential radon and risk of lung cancer - results of a collaborative analysis of 13 European case-control studies; Lungenkrebsrisiko durch Radon in Wohnungen. Ergebnisse der gemeinsamen Auswertung von 13 europaeischen Fall-Kontroll-Studien

    Energy Technology Data Exchange (ETDEWEB)

    Kreuzer, M. [Bundesamt fuer Strahlenschutz, Oberschleissheim (Germany)

    2005-07-01

    The combined analysis of the individual data from 13 European studies includes 7, 148 lung cancer patients and 14,208 controls. The database is currently the world wide largest database to investigate the association of lung cancer with residential radon. After detailed stratification for smoking, risk analyses showed an approximately linear exposure-response relationship with no evidence of a threshold dose. The excess relative risk was 16% per increase of radon exposure by 100 Bq/m{sup 3}. There was a significant linear exposure-response relationship even for radon concentrations of less than 200 Bq/m{sup 3}. (orig.)

  18. Vitamin D status during pregnancy and the risk of subsequent postpartum depression: a case-control study.

    Directory of Open Access Journals (Sweden)

    Nina O Nielsen

    Full Text Available Epidemiological studies have provided evidence of an association between vitamin D insufficiency and depression and other mood disorders, and a role for vitamin D in various brain functions has been suggested. We hypothesized that low vitamin D status during pregnancy might increase the risk of postpartum depression (PPD. The objective of the study was thus to determine whether low vitamin D status during pregnancy was associated with postpartum depression. In a case-control study nested in the Danish National Birth Cohort, we measured late pregnancy serum concentrations of 25[OH]D3 in 605 women with PPD and 875 controls. Odds ratios [OR for PPD were calculated for six levels of 25[OH]D3. Overall, we found no association between vitamin D concentrations and risk of PPD (p = 0.08. Compared with women with vitamin D concentrations between 50 and 79 nmol/L, the adjusted odds ratios for PPD were 1.35 (95% CI: 0.64; 2.85, 0.83 (CI: 0.50; 1.39 and 1.13 (CI: 0.84; 1.51 among women with vitamin D concentrations < 15 nmol/L, 15-24 nmol/L and 25-49 nmol/L, respectively, and 1.53 (CI: 1.04; 2.26 and 1.89 (CI: 1.06; 3.37 among women with vitamin D concentrations of 80-99 nmol/L and ≥ 100 nmol/L, respectively. In an additional analysis among women with sufficient vitamin D (≥ 50 nmol/L, we observed a significant positive association between vitamin D concentrations and PPD. Our results did not support an association between low maternal vitamin D concentrations during pregnancy and risk of PPD. Instead, an increased risk of PPD was found among women with the highest vitamin D concentrations.

  19. Responding to obesity in Brazil: understanding the international and domestic politics of policy reform through a nested analytic approach to comparative analysis.

    Science.gov (United States)

    Gómez, Eduardo J

    2015-02-01

    Why do governments pursue obesity legislation? And is the case of Brazil unique compared with other nations when considering the politics of policy reform? Using a nested analytic approach to comparative research, I found that theoretical frameworks accounting for why nations implement obesity legislation were not supported with cross-national statistical evidence. I then turned to the case of Brazil's response to obesity at three levels of government, national, urban, and rural, to propose alternative hypotheses for why nations pursue obesity policy. The case of Brazil suggests that the reasons that governments respond are different at these three levels. International forces, historical institutions, and social health movements were factors that prompted national government responses. At the urban and rural government levels, receiving federal financial assistance and human resource support appeared to be more important. The case of Brazil suggests that the international and domestic politics of responding to obesity are highly complex and that national and subnational political actors have different perceptions and interests when pursuing obesity legislation.

  20. HIF-1α 1772 C/T and 1790 G/A polymorphisms are significantly associated with higher cancer risk: an updated meta-analysis from 34 case-control studies.

    Directory of Open Access Journals (Sweden)

    Xi Yang

    Full Text Available BACKGROUND: HIF-1 activates various genes in cancer progression and metastasis. HIF-1α 1772 C/T and 1790 G/A polymorphisms are reportedly associated with cancer risk; however, the results are inconclusive. METHODOLOGY/PRINCIPAL FINDINGS: A meta-analysis of 34 studies that involved 7522 cases and 9847 controls for 1772 C/T and 24 studies that involved 4884 cases and 8154 controls for 1790 G/A was conducted to identify the association of C/T and G/A polymorphisms with cancer risk. Odds ratio (OR and 95% confidence intervals (95% CI were used to assess the strength of association. HIF-1α 1772 C/T and 1790 G/A polymorphisms were associated with higher cancer risk in homozygote comparison (1772C/T: TT vs. CC: OR = 2.45, 95% CI: 1.52, 3.96; P heterogeneity = 0.028; 1790G/A: AA vs. GG: OR=4.74, 95% CI: 1.78, 12.6; P heterogeneity < 0.01, dominant model (1772C/T: TT/CT vs. CC: OR = 1.27, 95% CI: 1.04, 1.55; P heterogeneity < 0.01, 1790G/A: AA/GA vs. GG: OR = 1.65, 95% CI: 1.05, 2.60; P heterogeneity < 0.01, T allele versus C allele (T vs. C: OR = 1.42, 95% CI: 1.18, 1.70; P heterogeneity < 0.01, and A allele versus G allele (A vs. G: OR = 1.83, 95% CI: 1.13, 2.96; P heterogeneity < 0.01. On a subgroup analysis, the 1772 C/T polymorphism was significantly linked to higher risks for breast cancer, lung cancer, prostate cancer, and cervical cancer, whereas the 1790 G/A polymorphism was significantly linked to higher risks for lung cancer and prostate cancer. A significantly increased cancer risk was found in both Asians and Caucasians for 1772C/T polymorphism, whereas a significantly increased cancer risk was found in Caucasians in the heterozygote comparison and recessive model for 1790G/A polymorphism. CONCLUSIONS: HIF-1α 1772 C/T and 1790 G/A polymorphisms are significantly associated with higher cancer risk.

  1. Nested Quantum Error Correction Codes

    CERN Document Server

    Wang, Zhuo; Fan, Hen; Vedral, Vlatko

    2009-01-01

    The theory of quantum error correction was established more than a decade ago as the primary tool for fighting decoherence in quantum information processing. Although great progress has already been made in this field, limited methods are available in constructing new quantum error correction codes from old codes. Here we exhibit a simple and general method to construct new quantum error correction codes by nesting certain quantum codes together. The problem of finding long quantum error correction codes is reduced to that of searching several short length quantum codes with certain properties. Our method works for all length and all distance codes, and is quite efficient to construct optimal or near optimal codes. Two main known methods in constructing new codes from old codes in quantum error-correction theory, the concatenating and pasting, can be understood in the framework of nested quantum error correction codes.

  2. Ouray National Wildlife Refuge : Duck nesting survey

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Summary report of the 1991 duck nest survey at Ouray National Wildlife Refuge. Key areas of the refuge were nest searched during the period between May 25th and July...

  3. Exceptional longevity and muscle and fitness related genotypes: a functional in vitro analysis and case-control association replication study with SNPs THRH rs7832552, IL6 rs1800795, and ACSL1 rs6552828

    Science.gov (United States)

    Fuku, Noriyuki; He, Zi-hong; Sanchis-Gomar, Fabian; Pareja-Galeano, Helios; Tian, Ye; Arai, Yasumichi; Abe, Yukiko; Murakami, Haruka; Miyachi, Motohiko; Zempo, Hirofumi; Naito, Hisashi; Yvert, Thomas; Verde, Zoraida; Venturini, Letizia; Fiuza-Luces, Carmen; Santos-Lozano, Alejandro; Rodriguez-Romo, Gabriel; Ricevuti, Giovanni; Hirose, Nobuyoshi; Emanuele, Enzo; Garatachea, Nuria; Lucia, Alejandro

    2015-01-01

    There are several gene variants that are candidates to influence functional capacity in long-lived individuals. As such, their potential association with exceptional longevity (EL, i.e., reaching 100+ years) deserves analysis. Among them are rs7832552 in the thyrotropin-releasing hormone receptor (TRHR) gene, rs1800795 in the interleukin-6 (IL6) gene and rs6552828 in the coenzyme A synthetase long-chain 1 (ACSL1) gene. To gain insight into their functionality (which is yet unknown), here we determined for the first time luciferase gene reporter activity at the muscle tissue level in rs7832552 and rs6552828. We then compared allele/genotype frequencies of the 3 abovementioned variants among centenarians [n = 138, age range 100–111 years (114 women)] and healthy controls [n = 334, 20–50 years (141 women)] of the same ethnic and geographic origin (Spain). We also studied healthy centenarians [n = 79, 100–104 years (40 women)] and controls [n = 316, 27–81 years (156 women)] from Italy, and centenarians [n = 742, 100–116 years (623 women)] and healthy controls [n = 499, 23–59 years (356 women)] from Japan. The THRH rs7832552 T-allele and ACSL1 rs6552828 A-allele up-regulated luciferase activity compared to the C and G-allele, respectively (P = 0.001). Yet we found no significant association of EL with rs7832552, rs1800795 or rs6552828 in any of the 3 cohorts. Further research is needed with larger cohorts of centenarians of different origin as well as with younger old people. PMID:25999849

  4. Matched case-control studies: a review of reported statistical methodology

    Directory of Open Access Journals (Sweden)

    Niven DJ

    2012-04-01

    Full Text Available Daniel J Niven1, Luc R Berthiaume2, Gordon H Fick1, Kevin B Laupland11Department of Critical Care Medicine, Peter Lougheed Centre, Calgary, 2Department of Community Health Sciences, University of Calgary, Calgary, Alberta, CanadaBackground: Case-control studies are a common and efficient means of studying rare diseases or illnesses with long latency periods. Matching of cases and controls is frequently employed to control the effects of known potential confounding variables. The analysis of matched data requires specific statistical methods.Methods: The objective of this study was to determine the proportion of published, peer reviewed matched case-control studies that used statistical methods appropriate for matched data. Using a comprehensive set of search criteria we identified 37 matched case-control studies for detailed analysis.Results: Among these 37 articles, only 16 studies were analyzed with proper statistical techniques (43%. Studies that were properly analyzed were more likely to have included case patients with cancer and cardiovascular disease compared to those that did not use proper statistics (10/16 or 63%, versus 5/21 or 24%, P = 0.02. They were also more likely to have matched multiple controls for each case (14/16 or 88%, versus 13/21 or 62%, P = 0.08. In addition, studies with properly analyzed data were more likely to have been published in a journal with an impact factor listed in the top 100 according to the Journal Citation Reports index (12/16 or 69%, versus 1/21 or 5%, P ≤ 0.0001.Conclusion: The findings of this study raise concern that the majority of matched case-control studies report results that are derived from improper statistical analyses. This may lead to errors in estimating the relationship between a disease and exposure, as well as the incorrect adaptation of emerging medical literature.Keywords: case-control, matched, dependent data, statistics

  5. Analysis of risk factors for upper gastrointestinal cancer in China: a multicentric population-based case-control study%上消化道三种恶性肿瘤的危险因素分析

    Institute of Scientific and Technical Information of China (English)

    陈万青; 贺宇彤; 孙喜斌; 温登瑰; 陈志峰; 赵德利

    2011-01-01

    Objective To explore the major risk factors for upper gastrointestinal cancer in high occurrence areas of esophageal and gastric cancer in China. Methods Four high occurrence areas of esophageal cancer, namely Cixian and Shexian from Hebei province, Linxian from Henan province, Feicheng from Shandong province, and Zhuanghe from Liaoning province, which is a high occurrence area of gastric cancer,were selected for the study. The newly-diagnosed cases whose date of onset were after January 1st,2009 were selected from the Cancer Registration Database in each district, and 751 cases diagnosed as cancers in lower segment of esophagus, cardiac and other subsite of stomach were randomly recruited. 2253 matched controls were selected to pair the cases at the ratio of 3: 1. The relative information of the study objects were collected from the face-to-face interviews with trained staff by designed questionnaires, and the data was input by EpiData software. Statistic software SPSS 13.0 was applied to conduct both univariate and multivariate logistic regression analysis to evaluate odd ratios (OR) and 95% confident interval (CI).Results As univariate analysis shown,66 objects in case group had irregular diet habit; while 90 in control group had ( OR= 3. 177;95% CI: 2. 127 - 4.745). A higher percentage in case group (83 objects)preferred fried food in comparison with only 214 in control group did (OR= 3. 190; 95% CI: 2.061 -4. 927). 369 objects in case group, but only 119 in control group had history of gastrointestinal diseases ( OR = 14. 660; 95% CI: 11. 342 - 18. 948 ). 282 objects in case group had history of gastroesophageal reflux disease (GERD) ,which was much higher than the percentage in control group (432 objects),with OR =3. 137 (95% CI: 2. 546 -3. 864). All the above factors could increase the risk for upper gastrointestinal cancer. 387 objects in case group and 1278 in control group reported they preferred fresh vegetables in daily diet,which was found to be a

  6. Determinants of brushite stone formation: a case-control study.

    Directory of Open Access Journals (Sweden)

    Roswitha Siener

    Full Text Available PURPOSE: The occurrence of brushite stones has increased during recent years. However, the pathogenic factors driving the development of brushite stones remain unclear. METHODS: Twenty-eight brushite stone formers and 28 age-, sex- and BMI-matched healthy individuals were enrolled in this case-control study. Anthropometric, clinical, 24 h urinary parameters and dietary intake from 7-day weighed food records were assessed. RESULTS: Pure brushite stones were present in 46% of patients, while calcium oxalate was the major secondary stone component. Urinary pH and oxalate excretion were significantly higher, whereas urinary citrate was lower in patients as compared to healthy controls. Despite lower dietary intake, urinary calcium excretion was significantly higher in brushite stone patients. Binary logistic regression analysis revealed pH>6.50 (OR 7.296; p = 0.035, calcium>6.40 mmol/24 h (OR 25.213; p = 0.001 and citrate excretion <2.600 mmol/24 h (OR 15.352; p = 0.005 as urinary risk factors for brushite stone formation. A total of 56% of patients exhibited distal renal tubular acidosis (dRTA. Urinary pH, calcium and citrate excretion did not significantly differ between patients with or without dRTA. CONCLUSIONS: Hypercalciuria, a diminished citrate excretion and an elevated pH turned out to be the major urinary determinants of brushite stone formation. Interestingly, urinary phosphate was not associated with urolithiasis. The increased urinary oxalate excretion, possibly due to decreased calcium intake, promotes the risk of mixed stone formation with calcium oxalate. Neither dietary factors nor dRTA can account as cause for hypercalciuria, higher urinary pH and diminished citrate excretion. Further research is needed to define the role of dRTA in brushite stone formation and to evaluate the hypothesis of an acquired acidification defect.

  7. Risk factors for episiotomy: a case-control study

    Directory of Open Access Journals (Sweden)

    Giordana Campos Braga

    2014-10-01

    Full Text Available Objective: obtaining information on the factors associated with episiotomy will be useful in sensitizing professionals to the need to minimize its incidence. Therefore, the objective of this study was to evaluate risk factors for episiotomy in pregnant women who had undergone vaginal delivery at a university maternity hospital in northeastern Brazil. Methods: a case-control study was conducted with pregnant women submitted to episiotomy (cases and pregnant women not submitted to episiotomy (controls between March 2009 and July 2010 at the Professor Fernando Figueira Integral Medicine Institute (IMIP in Recife, Brazil, in a ratio of 1 case to 2 controls. The study variables consisted of: whether episiotomy was performed, demographic, obstetric and fetal characteristics (primiparity, analgesia, instrumental delivery, fetal distress, etc., external factors (day and time of delivery, professional attending delivery and factors directly related to delivery. Odds ratios (OR and 95% confidence intervals (95%CI were calculated. Multivariate analysis was performed to determine the adjusted risk of episiotomy. Results: a total of 522 women (173 cases and 349 controls were included. It was found that deliveries with episiotomy were more likely to have been attended by staff physicians (OR = 1.88; 95%CI: 1.01 - 3.48, to have required forceps (OR = 12.31; 95%CI: 4.9 - 30.1 and to have occurred in primiparas (OR = 4.24; 95%CI: 2.61 - 6.89. The likelihood of a nurse having attended the delivery with episiotomy was significantly lower (OR = 0.29; 95%CI: 0.16 - 0.55. Conclusion: episiotomy was found to be strongly associated with deliveries attended by staff physicians, with primiparity, and with instrumental delivery, and was less common in deliveries attended by nurses.

  8. Sexual Dysfunction in Breast Cancer: A Case-Control Study

    Directory of Open Access Journals (Sweden)

    Mandana Ebrahimi

    2015-02-01

    Full Text Available Background: Sexual dysfunction in breast cancer patients is considered as a common and distressing problem. Considering the increasing number of breast cancer survivors living for longer periods of time with the disease and the importance of their quality of life, we conducted the present study to compare the sexual functioning in breast cancer patients with their healthy counterparts.Methods: In this case-control study, breast cancer patients who completed their treatment protocol and were followed up for at least six months were included. The controls were healthy women with normal clinical breast examinations. All subjects filled-in the Persian version of Female Sexual Function Index questionnaire.Results: A total of 165 subjects including 71 breast cancer patients and 94 healthy women were studied. The frequency of sexual dysfunction in cases and controls was 52.6% and 47.4%, respectively (P = 0.09. There were no significant differences between the two groups regarding domain scores, except for vaginal lubrication (P = 0.045. Logistic regression analysis indicated that significant determinants of sexual dysfunction in breast cancer group was patients' age (OR = 4.0, 95%CI: 1.3 – 11.5, P = 0.01 and age of the spouse (OR= 9.8, 95% CI: 1.8-51.9, P= 0.007, while in controls, only emotional relationship with the husband was the significant predictive factor (OR = 6.3, 95%CI: 1.9 – 20.5, P = 0.002.Conclusions: Our findings indicated that sexual dysfunction is prevalent in Iranian women regardless of their physical health status. The frequency of vaginal dryness in breast cancer patients was significantly higher than controls. Age of the patient and the spouse (>40 were the only significant predictors of sexual dysfunction among women with breast cancer. Preventive strategies, sexual education and access to effective treatment should be planned in supportive care of breast cancer patients.

  9. Facial dermatosis associated with Demodex: a case-control study.

    Science.gov (United States)

    Zhao, Ya-e; Peng, Yan; Wang, Xiang-lan; Wu, Li-ping; Wang, Mei; Yan, Hu-ling; Xiao, Sheng-xiang

    2011-12-01

    Demodex has been considered to be related with multiple skin disorders, but controversy persists. In this case-control study, a survey was conducted with 860 dermatosis patients aged 12 to 84 years in Xi'an, China to identify the association between facial dermatosis and Demodex. Amongst the patients, 539 suffered from facial dermatosis and 321 suffered from non-facial dermatosis. Demodex mites were sampled and examined using the skin pressurization method. Multivariate regression analysis was applied to analyze the association between facial dermatosis and Demodex infestation, and to identify the risk factors of Demodex infestation. The results showed that total detection rate of Demodex was 43.0%. Patients aged above 30 years had higher odds of Demodex infestation than those under 30 years. Compared to patients with neutral skin, patients with mixed, oily, or dry skin were more likely to be infested with Demodex (odds ratios (ORs) were 2.5, 2.4, and 1.6, respectively). Moreover, Demodex infestation was found to be statistically associated with rosacea (OR=8.1), steroid-induced dermatitis (OR=2.7), seborrheic dermatitis (OR=2.2), and primary irritation dermatitis (OR=2.1). In particular, ORs calculated from the severe infestation (≥5 mites/cm(2)) rate were significantly higher than those of the total rate. Therefore, we concluded that Demodex is associated with rosacea, steroid-induced dermatitis, seborrheic dermatitis, and primary irritation dermatitis. The rate of severe infestation is found to be more correlated with various dermatosis than the total infestation rate. The risk factors of Demodex infestation, age, and skin types were identified. Our study also suggested that good hygiene practice might reduce the chances of demodicosis and Demodex infestation.

  10. Lupus Myocarditis: A Case-Control Study from China

    Institute of Scientific and Technical Information of China (English)

    Li Zhang; Yan-Lin Zhu; Meng-Tao Li; Na Gao; Xin You; Qing-Jun Wu; Jin-Mei Su

    2015-01-01

    Background:Myocarditis is an uncommon but serious manifestation of systemic lupus erythematosus (SLE).This study aimed to investigate clinical characteristics and outcomes of lupus myocarditis (LM) and to determine risk factors of LM in hospitalized Chinese patients with SLE.Methods:We conducted a retrospective case-control study.A total of 25 patients with LM from 2001 to 2012 were enrolled as the study group,and 1 O0 patients with SLE but without LM were randomly pooled as the control group.Univariable analysis was performed using Chi-square tests for categorical variables,and the Student's t-test or Mann-Whitney U-test was performed for continuous variables according to the normality.Results:LM presented as the initial manifestation of SLE in 7 patients (28%) and occurred mostly at earlier stages compared to the controls (20.88 ± 35.73 vs.44.08 ± 61.56 months,P =0.008).Twenty-one patients (84%) experienced episodes of symptomatic heart failure.Echocardiography showed that 23 patients (92%) had decreased left ventricular ejection fraction (<50%) and all patients had wall motion abnormalities.A high SLE Disease Activity Index was the independent risk factor in the development of LM (odds ratio =1.322,P < 0.001).With aggressive immunosuppressive therapies,most patients achieved satisfactory outcome.The in-hospital mortality was not significantly higher in the LM group than in the controls (4% vs.2%,P =0.491).Conclusions:LM could result in cardiac dysfunction and even sudden death.High SLE disease activity might potentially predict the occurrence of LM at the early stage of SLE.Characteristic echocardiographic findings could confirm the diagnosis of LM.Early aggressive immunosuppressive therapy could improve the cardiac outcome of LM.

  11. Facial dermatosis associated with Demodex: a case-control study

    Institute of Scientific and Technical Information of China (English)

    Ya-e ZHAO; Yah PENG; Xiang-lan WANG; Li-ping WU; Mei WANG; Hu-ling YAN; Sheng-xiang XIAO

    2011-01-01

    Demodex has been considered to be related with multiple skin disorders,but controversy persists.In this case-control study,a survey was conducted with 860 dermatosis patients aged 12 to 84 years in Xi'an,China to identify the association between facial dermatosis and Demodex.Amongst the patients,539 suffered from facial dermatosis and 321 suffered from non-facial dermatosis.Demodex mites were sampled and examined using the skin pressurization method.Multivariate regression analysis was applied to analyze the association between facial dermatosis and Demodex infestation,and to identify the risk factors of Demodex infestation.The results showed that total detection rate of Demodex was 43.0%.Patients aged above 30 years had higher odds of Demodex infestation than those under 30 years.Compared to patients with neutral skin,patients with mixed,oily,or dry skin were more likely to be infested with Demodex (odds ratios (ORs) were 2.5,2.4,and 1.6,respectively).Moreover,Demodex infestation was found to be statistically associated with rosacea (OR=8.1),steroid-induced dermatitis (OR=2.7),seborrheic dermatitis (OR=2.2),and primary irritation dermatitis (OR=2.1).In particular,ORs calculated from the severe infestation (≥5 mites/cm2) rate were significantly higher than those of the total rate.Therefore,we concluded that Demodex is associated with rosacea,steroid-induced dermatitis,seborrheic dermatitis,and primary irritation dermatitis.The rate of severe infestation is found to be more correlated with various dermatosis than the total infestation rate.The risk factors of Demodex infestation,age,and skin types were identified.Our study also suggested that good hygiene practice might reduce the chances of demodicosis and Demodex infestation.

  12. Toxocariasis in waste pickers: a case control seroprevalence study.

    Directory of Open Access Journals (Sweden)

    Cosme Alvarado-Esquivel

    Full Text Available BACKGROUND: The epidemiology of Toxocara infection in humans in Mexico has been poorly explored. There is a lack of information about Toxocara infection in waste pickers. AIMS: Determine the seroepidemiology of Toxocara infection in waste pickers. METHODS: Through a case control study design, the presence of anti-Toxocara IgG antibodies was determined in 90 waste pickers and 90 age- and gender-matched controls using an enzyme-linked immunoassay. Associations of Toxocara exposure with socio-demographic, work, clinical, and behavioral data of the waste pickers were also evaluated. RESULTS: The seroprevalence of anti-Toxocara IgG antibodies was significantly higher in waste pickers (12/90: 13% than in control subjects (1/90: 1% (OR = 14; 95% CI: 2-288. The seroprevalence was not influenced by socio-demographic or work characteristics. In contrast, increased seroprevalence was found in waste pickers suffering from gastritis, and reflex and visual impairments. Multivariate analysis showed that Toxocara exposure was associated with a low frequency of eating out of home (OR = 26; 95% CI: 2-363 and negatively associated with consumption of chicken meat (OR = 0.03; 95% CI: 0.003-0.59. Other behavioral characteristics such as animal contacts or exposure to soil were not associated with Toxocara seropositivity. CONCLUSIONS: 1 Waste pickers are a risk group for Toxocara infection. 2 Toxocara is impacting the health of waste pickers. This is the first report of Toxocara exposure in waste pickers and of associations of gastritis and reflex impairment with Toxocara seropositivity. Results warrant for further research.

  13. Effect of heterogeneity of nest boxes on occurrence of gregarious nesting in laying hens

    DEFF Research Database (Denmark)

    Clausen, Tina; Riber, Anja Brinch

    2012-01-01

    Gregarious nesting, where hens select already occupied nest boxes even when other nest boxes are unoccupied, is an unwanted behaviour in laying hens that may reduce animal welfare and pose a financial cost to the producer. It has been suggested that gregarious nesting is caused by the difficulties...... experienced by hens in distinguishing between nest boxes in long rows of identical boxes. Heterogeneity of nest boxes has therefore been suggested as a method to reduce gregarious nesting. To test this hypothesis two experiments were performed. Twelve groups of 13–15 ISA Warren hens 27 weeks of age were...... nesting was higher in experimental groups compared to control groups (P laying period did not differ between the experimental and control groups (P = 0.41). Numbers of visits to and eggs laid in nest boxes positioned either left or right were higher compared to nest boxes positioned...

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

    Directory of Open Access Journals (Sweden)

    Mistry Pramod K

    2011-09-01

    Full Text Available Abstract Background 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. Methods 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. Results 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. Conclusions 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.

  15. Case-control analysis of paternal age and trisomic anomalies

    DEFF Research Database (Denmark)

    De Souza, E; Morris, David Jackson; Garne, Ester

    2010-01-01

    To determine whether older paternal age increases the risk of fathering a pregnancy with Patau (trisomy 13), Edwards (trisomy 18), Klinefelter (XXY) or XYY syndrome.......To determine whether older paternal age increases the risk of fathering a pregnancy with Patau (trisomy 13), Edwards (trisomy 18), Klinefelter (XXY) or XYY syndrome....

  16. Case-control studies for identifying novel teratogens.

    Science.gov (United States)

    Werler, Martha M; Louik, Carol; Mitchell, Allen A

    2011-08-15

    The case-control study design offers an operationally efficient approach to measuring an association between an exposure and an outcome, especially when the outcome is rare, as is true for specific birth defects. For example, instead of following 50,000 pregnant women to have sufficient statistical power to identify a doubling in risk of oral clefts associated with a common exposure (e.g., cigarette smoking), 75 cases and 3 controls per case could be studied with equal statistical power. Examples of case sources include hospital or clinical series, or birth defect registries. For validity, control subjects should represent the population base of the cases, which can be difficult to identify for non-population-based case groups. Case-control studies typically rely on retrospective exposure measurement, which presents a major challenge and sets up the possibility of recall bias. Approaches are discussed to keep sources of bias to a minimum, including recall, non-differential information, and selection biases. Case-control studies can play an important role in this process for both hypothesis-generation and hypothesis-testing of potential teratogens. Examples of case-control studies and their contributions to the field are presented. © 2011 Wiley-Liss, Inc.

  17. Resistance to gray leaf spot of maize: genetic architecture and mechanisms elucidated through nested association mapping and near-isogenic line analysis.

    Directory of Open Access Journals (Sweden)

    Jacqueline M Benson

    2015-03-01

    Full Text Available Gray leaf spot (GLS, caused by Cercospora zeae-maydis and Cercospora zeina, is one of the most important diseases of maize worldwide. The pathogen has a necrotrophic lifestyle and no major genes are known for GLS. Quantitative resistance, although poorly understood, is important for GLS management. We used genetic mapping to refine understanding of the genetic architecture of GLS resistance and to develop hypotheses regarding the mechanisms underlying quantitative disease resistance (QDR loci. Nested association mapping (NAM was used to identify 16 quantitative trait loci (QTL for QDR to GLS, including seven novel QTL, each of which demonstrated allelic series with significant effects above and below the magnitude of the B73 reference allele. Alleles at three QTL, qGLS1.04, qGLS2.09, and qGLS4.05, conferred disease reductions of greater than 10%. Interactions between loci were detected for three pairs of loci, including an interaction between iqGLS4.05 and qGLS7.03. Near-isogenic lines (NILs were developed to confirm and fine-map three of the 16 QTL, and to develop hypotheses regarding mechanisms of resistance. qGLS1.04 was fine-mapped from an interval of 27.0 Mb to two intervals of 6.5 Mb and 5.2 Mb, consistent with the hypothesis that multiple genes underlie highly significant QTL identified by NAM. qGLS2.09, which was also associated with maturity (days to anthesis and with resistance to southern leaf blight, was narrowed to a 4-Mb interval. The distance between major leaf veins was strongly associated with resistance to GLS at qGLS4.05. NILs for qGLS1.04 were treated with the C. zeae-maydis toxin cercosporin to test the role of host-specific toxin in QDR. Cercosporin exposure increased expression of a putative flavin-monooxygenase (FMO gene, a candidate detoxification-related gene underlying qGLS1.04. This integrated approach to confirming QTL and characterizing the potential underlying mechanisms advances the understanding of QDR and will

  18. Nest Predation Deviates from Nest Predator Abundance in an Ecologically Trapped Bird.

    Science.gov (United States)

    Hollander, Franck A; Van Dyck, Hans; San Martin, Gilles; Titeux, Nicolas

    2015-01-01

    In human-modified environments, ecological traps may result from a preference for low-quality habitat where survival or reproductive success is lower than in high-quality habitat. It has often been shown that low reproductive success for birds in preferred habitat types was due to higher nest predator abundance. However, between-habitat differences in nest predation may only weakly correlate with differences in nest predator abundance. An ecological trap is at work in a farmland bird (Lanius collurio) that recently expanded its breeding habitat into open areas in plantation forests. This passerine bird shows a strong preference for forest habitat, but it has a higher nest success in farmland. We tested whether higher abundance of nest predators in the preferred habitat or, alternatively, a decoupling of nest predator abundance and nest predation explained this observed pattern of maladaptive habitat selection. More than 90% of brood failures were attributed to nest predation. Nest predator abundance was more than 50% higher in farmland, but nest predation was 17% higher in forest. Differences between nest predation on actual shrike nests and on artificial nests suggested that parent shrikes may facilitate nest disclosure for predators in forest more than they do in farmland. The level of caution by parent shrikes when visiting their nest during a simulated nest predator intrusion was the same in the two habitats, but nest concealment was considerably lower in forest, which contributes to explaining the higher nest predation in this habitat. We conclude that a decoupling of nest predator abundance and nest predation may create ecological traps in human-modified environments.

  19. Acute myeloid leukemia in adults: a case-control study in Yorkshire.

    Science.gov (United States)

    Cartwright, R A; Darwin, C; McKinney, P A; Roberts, B; Richards, I D; Bird, C C

    1988-10-01

    This paper reports the results of a case-control analysis of 161 cases of acute myeloid leukemia and 310 matched hospital controls. The patients were interviewed between 1982 and 1986. The study shows a weak association for cases with previous malignant disease. Furnace workers show excess risks. Urticaria and vertigo are in excess, as well as some aspects of family medical histories, including multiple sclerosis and cases of leukemia/lymphoma in blood relations.

  20. DNest3: Diffusive Nested Sampling

    Science.gov (United States)

    Brewer, Brendon

    2016-04-01

    DNest3 is a C++ implementation of Diffusive Nested Sampling (ascl:1010.029), a Markov Chain Monte Carlo (MCMC) algorithm for Bayesian Inference and Statistical Mechanics. Relative to older DNest versions, DNest3 has improved performance (in terms of the sampling overhead, likelihood evaluations still dominate in general) and is cleaner code: implementing new models should be easier than it was before. In addition, DNest3 is multi-threaded, so one can run multiple MCMC walkers at the same time, and the results will be combined together.

  1. Nested-cone transformer antenna

    Science.gov (United States)

    Ekdahl, Carl A.

    1991-01-01

    A plurality of conical transmission lines are concentrically nested to form n output antenna for pulsed-power, radio-frequency, and microwave sources. The diverging conical conductors enable a high power input density across a bulk dielectric to be reduced below a breakdown power density at the antenna interface with the transmitting medium. The plurality of cones maintain a spacing between conductors which minimizes the generation of high order modes between the conductors. Further, the power input feeds are isolated at the input while enabling the output electromagnetic waves to add at the transmission interface. Thus, very large power signals from a pulse rf, or microwave source can be radiated.

  2. A case-control study of the relationship between hepatitis B virus DNA level and risk of hepatocellular carcinoma in Qidong, China

    Institute of Scientific and Technical Information of China (English)

    Tao-Tao Liu; Ying Fang; Hui Xiong; Tao-Yang Chen; Zheng-Pin Ni; Jian-Feng Luo; Nai-Qing Zhao; Xi-Zhong Shen

    2008-01-01

    AIM: To investigate the role of hepatitis B virus (HBV)replication in the development of hepatocellular carcinoma (HCC), a nested case-control study was performed to study the relationship between HBV DNA level and risk of HCC.METHODS: One hundred and seventy cases of HCC and 276 control subjects free of HCC and cirrhosis were selected for this study. Serum HBV DNA level was measured using fluorescein quantitative polymerase chain reaction at study entry and the last visit.RESULTS: In a binary unconditional logistic regression analysis adjusted for age, cigarette smoking, alcohol consumption and family history of chronic liver diseases,the adjusted odds ratios (95% confidence intervals) of HCC in patients with increasing HBV DNA level were 2.834 (1.237-6.492), 48.403 (14.392-162.789), 42.252(14.784-120.750), and 14.819 (6.992-31.411) for HBV DNA levels ≥ 104 to < 105; ≥ 105 to < 105; ≥ 106 to < 107;≥ 107 copies/mL, respectively. Forty-six HCC cases were selected to compare the serums viral loads of HBV DNA at study entry with those at the last visit. The HBV DNA levels measured at the two time points did not differ significantly.CONCLUSION: The findings of this study provide strong longitudinal evidence of an increased risk of HCC associated with persistent elevation of serum HBV DNA level in the 104-107 range.

  3. Social waves in giant honeybees (Apis dorsata) elicit nest vibrations.

    Science.gov (United States)

    Kastberger, Gerald; Weihmann, Frank; Hoetzl, Thomas

    2013-07-01

    Giant honeybees (Apis dorsata) nest in the open and have developed a wide array of strategies for colony defence, including the Mexican wave-like shimmering behaviour. In this collective response, the colony members perform upward flipping of their abdomens in coordinated cascades across the nest surface. The time-space properties of these emergent waves are response patterns which have become of adaptive significance for repelling enemies in the visual domain. We report for the first time that the mechanical impulse patterns provoked by these social waves and measured by laser Doppler vibrometry generate vibrations at the central comb of the nest at the basic (='natural') frequency of 2.156 ± 0.042 Hz which is more than double the average repetition rate of the driving shimmering waves. Analysis of the Fourier spectra of the comb vibrations under quiescence and arousal conditions provoked by mass flight activity and shimmering waves gives rise to the proposal of two possible models for the compound physical system of the bee nest: According to the elastic oscillatory plate model, the comb vibrations deliver supra-threshold cues preferentially to those colony members positioned close to the comb. The mechanical pendulum model predicts that the comb vibrations are sensed by the members of the bee curtain in general, enabling mechanoreceptive signalling across the nest, also through the comb itself. The findings show that weak and stochastic forces, such as general quiescence or diffuse mass flight activity, cause a harmonic frequency spectrum of the comb, driving the comb as an elastic plate. However, shimmering waves provide sufficiently strong forces to move the nest as a mechanical pendulum. This vibratory behaviour may support the colony-intrinsic information hypothesis herein that the mechanical vibrations of the comb provoked by shimmering do have the potential to facilitate immediate communication of the momentary defensive state of the honeybee nest to

  4. Use of disulfiram and risk of cancer: a population-based case-control study.

    Science.gov (United States)

    Askgaard, Gro; Friis, Søren; Hallas, Jesper; Thygesen, Lau C; Pottegård, Anton

    2014-05-01

    Experimental studies have indicated that disulfiram (Antabuse) has antineoplastic effects against melanoma, breast, and prostate cancer. To explore this hypothesis, we examined the association between disulfiram use and these cancers in a nationwide register-based case-control study nested within ever-users (≥one prescription) of disulfiram. Cases were all Danish individuals with a histologically verified first-time diagnosis of malignant melanoma, breast, or prostate cancer during 2000-2009. For each case, we selected four cancer-free controls matched for age, sex, and year of first disulfiram prescription using risk set sampling. Similarly, for secondary analyses, we selected case-control populations for selected tobacco-related and alcohol-related cancer types, that is, cancers of the buccal cavity, liver, lung, and colorectal cancer. Disulfiram use 1 year before cancer diagnosis and the corresponding date for controls were disregarded. We estimated crude and adjusted odds ratios and 95% confidence intervals (CI) for cancer associated with long-term (≥500 daily defined doses) versus one-time (one prescription) use of disulfiram. Among 53 856 disulfiram users, we identified 166, 644, and 464 cases, respectively, of melanoma, breast, or prostate cancer. Adjusted odds ratios for melanoma, breast, or prostate cancer associated with long-term disulfiram use were 1.04 (95% CI: 0.60-1.78), 0.92 (95% CI: 0.70-1.22), and 0.77 (95% CI: 0.56-1.06), respectively. For prostate cancer, dose-response analyses showed a further risk reduction with the highest cumulative dose level of disulfiram; however, the test for trend did not reach statistical significance. Our study provides some epidemiological support for a protective effect of disulfiram against prostate and breast cancer.

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

    Directory of Open Access Journals (Sweden)

    Karin Bammann

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

  6. Polytypic Functions Over Nested Datatypes

    Directory of Open Access Journals (Sweden)

    Ralf Hinze

    1999-12-01

    Full Text Available The theory and practice of polytypic programming is intimately connected with the initial algebra semantics of datatypes. This is both a blessing and a curse. It is a blessing because the underlying theory is beautiful and well developed. It is a curse because the initial algebra semantics is restricted to so-called regular datatypes. Recent work by R. Bird and L. Meertens [3] on the semantics of non-regular or nested datatypes suggests that an extension to general datatypes is not entirely straightforward. Here we propose an alternative that extends polytypism to arbitrary datatypes, including nested datatypes and mutually recursive datatypes. The central idea is to use rational trees over a suitable set of functor symbols as type arguments for polytypic functions. Besides covering a wider range of types the approach is also simpler and technically less involving than previous ones. We present several examples of polytypic functions, among others polytypic reduction and polytypic equality. The presentation assumes some background in functional and in polytypic programming. A basic knowledge of monads is required for some of the examples.

  7. Nested PCR for specific diagnosis of Taenia solium taeniasis.

    Science.gov (United States)

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

    2008-01-01

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

  8. Nesting ecology of Chelonia mydas (Testudines: Cheloniidae) on the Guanahacabibes Peninsula, Cuba.

    Science.gov (United States)

    Azanza Ricardo, Julia; Ibarra Martín, Maria E; González Sansón, Gaspar; Abreu Grobois, F Alberto; Eckert, Karen L; Espinosa López, Georgina; Oyama, Ken

    2013-12-01

    The nesting colony of green sea turtles (Chelonia mydas) at Guanahacabibes Peninsula Biosphere Reserve and National Park is one of the largest in the Cuban archipelago; however, little information about its nesting ecology is available. Temporal and spatial variation in nesting and reproductive success as well as morphometric characteristics of gravid females were used to ecologically characterize this colony. Nine beaches of the Southernmost coast of Guanahacabibes Peninsula were monitored for 14 years (1998-2012) to determine green turtle nesting activity, from May to September (peak nesting season in this area). Beach dimensions were measured to determine nest density using the length and the area. Afterward the beaches were divided in two categories, index and secondary. Females were measured and tagged to compare new tagged females (823) with returning tagged females (140). Remigration interval was also determined. Temporal variation was identified as the annual number of nesting emergences and oviposits per female, with apparent peaks in reproductive activity on a biennial cycle in the first six years followed by periods of annual increase in nest number (2003-2008) and periods of decreasing number of nests (2010-2012). We also found intra-seasonal variation with the highest nesting activity in July, particularly in the second half of the month. The peak emergence time was 22:00-02:00 hr. In terms of spatial variation, smaller beaches had the highest nest density and nesting was more frequent 6-9m from the high tide line, where hatchling production was maximized although hatchling success was high on average, above 80%. Morphometric analysis of females was made and newly tagged turtles were smaller on average than remigrants. Our results are only a first attempt at characterizing Guanahacabibes' populations but have great value for establishing conservation priorities within the context of national management plans, and for efficient monitoring and protection

  9. Hydrodynamic modeling of Singapore's coastal waters: Nesting and model accuracy

    Science.gov (United States)

    Hasan, G. M. Jahid; van Maren, Dirk Sebastiaan; Ooi, Seng Keat

    2016-01-01

    The tidal variation in Singapore's coastal waters is influenced by large-scale, complex tidal dynamics (by interaction of the Indian Ocean and the South China Sea) as well as monsoon-driven low frequency variations, requiring a model with large spatial coverage. Close to the shores, the complex topography, influenced by headlands and small islands, requires a high resolution model to simulate tidal dynamics. This can be achieved through direct nesting or multi-scale nesting, involving multiple model grids. In this paper, we investigate the effect of grid resolution and multi-scale nesting on the tidal dynamics in Singapore's coastal waters, by comparing model results with observations using different statistical techniques. The results reveal that the intermediate-scale model is generally sufficiently accurate (equal to or better than the most refined model), but also that the most refined model is only more accurate when nested in the intermediate scale model (requiring multi-scale nesting). This latter is the result of the complex tidal dynamics around Singapore, where the dominantly diurnal tidal currents are decoupled from the semi-diurnal water level variations. Furthermore, different techniques to quantify model accuracy (harmonic analysis, basic statistics and more complex statistics) are inconsistent in determining which model is more accurate.

  10. Eggs in the Freezer: Energetic Consequences of Nest Site and Nest Design in Arctic Breeding Shorebirds

    Science.gov (United States)

    Tulp, Ingrid; Schekkerman, Hans; de Leeuw, Joep

    2012-01-01

    Birds construct nests for several reasons. For species that breed in the Arctic, the insulative properties of nests are very important. Incubation is costly there and due to an increasing surface to volume ratio, more so in smaller species. Small species are therefore more likely to place their nests in thermally favourable microhabitats and/or to invest more in nest insulation than large species. To test this hypothesis, we examined characteristics of nests of six Arctic breeding shorebird species. All species chose thermally favourable nesting sites in a higher proportion than expected on the basis of habitat availability. Site choice did not differ between species. Depth to frozen ground, measured near the nests, decreased in the course of the season at similar non-species-specific speeds, but this depth increased with species size. Nest cup depth and nest scrape depth (nest cup without the lining) were unrelated to body mass (we applied an exponent of 0.73, to account for metabolic activity of the differently sized species). Cup depth divided by diameter2 was used as a measure of nest cup shape. Small species had narrow and deep nests, while large species had wide shallow nests. The thickness of nest lining varied between 0.1 cm and 7.6 cm, and decreased significantly with body mass. We reconstruct the combined effect of different nest properties on the egg cooling coefficient using previously published quantitative relationships. The predicted effect of nest cup depth and lining depth on heat loss to the frozen ground did not correlate with body mass, but the sheltering effect of nest cup diameter against wind and the effects of lining material on the cooling coefficient increased with body mass. Our results suggest that small arctic shorebirds invest more in the insulation of their nests than large species. PMID:22701596

  11. Trypanosoma cruzi-associated cerebrovascular disease: a case-control study in Eastern Colombia.

    Science.gov (United States)

    Leon-Sarmiento, Fidias E; Mendoza, Eder; Torres-Hillera, Martin; Pinto, Neyla; Prada, Janette; Silva, Clara A; Vera, Silvia J; Castillo, Erwin; Valderrama, Vladimir; Prada, Didier G; Bayona-Prieto, Jaime; Garcia, Ingrid

    2004-01-15

    Trypanosoma cruzi infection is a common cause of cardiopathy in South America leading it eventually to an established stroke; however, the association between T. cruzi infection itself and cerebrovascular disease is still unknown. We did a case-control study at Eastern Colombia and found that T. cruzi infection was more frequent and statistically significant in stroke cases (24.4%) than controls (1.9%), (Chi square: 21.72; OR: 16.13; 95% confidence interval (CI): 3.64-71.4; p<0.00001). After removing the seropositive patients with cardiological abnormalities, the significance still remained by multivariate analysis (p<0.05). This is the first case-control study that demonstrated a significant link between this infection and symptomatic cerebrovascular disease, mainly ischemic, regardless of cardiac abnormalities. Therefore, we recommend that patients with stroke must be screened for T. cruzi infection if they currently live or have lived in places where this parasite is considered endemic.

  12. Nest architecture shapes the collective behaviour of harvester ants.

    Science.gov (United States)

    Pinter-Wollman, Noa

    2015-10-01

    Structures influence how individuals interact and, therefore, shape the collective behaviours that emerge from these interactions. Here I show that the structure of a nest influences the collective behaviour of harvester ant colonies. Using network analysis, I quantify nest architecture and find that as chamber connectivity and redundancy of connections among chambers increase, so does a colony's speed of recruitment to food. Interestingly, the volume of the chambers did not influence speed of recruitment, suggesting that the spatial organization of a nest has a greater impact on collective behaviour than the number of workers it can hold. Thus, by changing spatial constraints on social interactions organisms can modify their behaviour and impact their fitness.

  13. Exploring Multi-Modal Distributions with Nested Sampling

    CERN Document Server

    Feroz, F

    2013-01-01

    In performing a Bayesian analysis, two difficult problems often emerge. First, in estimating the parameters of some model for the data, the resulting posterior distribution may be multi-modal or exhibit pronounced (curving) degeneracies. Secondly, in selecting between a set of competing models, calculation of the Bayesian evidence for each model is computationally expensive using existing methods such as thermodynamic integration. Nested Sampling is a Monte Carlo method targeted at the efficient calculation of the evidence, but also produces posterior inferences as a by-product and therefore provides means to carry out parameter estimation as well as model selection. The main challenge in implementing Nested Sampling is to sample from a constrained probability distribution. One possible solution to this problem is provided by the Galilean Monte Carlo (GMC) algorithm. We show results of applying Nested Sampling with GMC to some problems which have proven very difficult for standard Markov Chain Monte Carlo (MC...

  14. A semiparametric efficient estimator in case-control studies

    CERN Document Server

    Ma, Yanyuan

    2010-01-01

    We construct a semiparametric estimator in case-control studies where the gene and the environment are assumed to be independent. A discrete or continuous parametric distribution of the genes is assumed in the model. A discrete distribution of the genes can be used to model the mutation or presence of certain group of genes. A continuous distribution allows the distribution of the gene effects to be in a finite-dimensional parametric family and can hence be used to model the gene expression levels. We leave the distribution of the environment totally unspecified. The estimator is derived through calculating the efficiency score function in a hypothetical setting where a close approximation to the samples is random. The resulting estimator is proved to be efficient in the hypothetical situation. The efficiency of the estimator is further demonstrated to hold in the case-control setting as well.

  15. Selection of controls in case-control studies. I. Principles.

    Science.gov (United States)

    Wacholder, S; McLaughlin, J K; Silverman, D T; Mandel, J S

    1992-05-01

    A synthesis of classical and recent thinking on the issues involved in selecting controls for case-control studies is presented in this and two companion papers (S. Wacholder et al. Am J Epidemiol 1992;135:1029-50). In this paper, a theoretical framework for selecting controls in case-control studies is developed. Three principles of comparability are described: 1) study base, that all comparisons be made within the study base; 2) deconfounding, that comparisons of the effects of the levels of exposure on disease risk not be distorted by the effects of other factors; and 3) comparable accuracy, that any errors in measurement of exposure be nondifferential between cases and controls. These principles, if adhered to in a study, can reduce selection, confounding, and information bias, respectively. The principles, however, are constrained by an additional efficiency principle regarding resources and time. Most problems and controversies in control selection reflect trade-offs among these four principles.

  16. Nest-site selection pattern of Grusjaponensis in Zhalong Nature Reserve of northeast China

    Institute of Scientific and Technical Information of China (English)

    WU Qing-ming; ZOU Hong-fei

    2011-01-01

    Nest-site selection patterns of Red-crowned cranes (Grus japonensis) and the effects of environmental variables were studied during the years of 2002-2008 in Zhalong Nature Reserve, Qiqihar city,northeast China. The nest-site selection pattern of Red-crowned cranes included two orders and three choices: the choice of nest-site habitat type within the macro-habitat order, nest zone selection and nest-site micro-habitat selection within the micro-habitat order. Various habitats (such as Carex swamps and reed fire districts) can be selected as the nest sites for Red-crowned cranes, of which reed swamps (93.15%) are given a preference. Factor Analysis reveals that the micro-habitat selection are affected by four main factors: fire, security (concealment / disturbance),incubation (conditions, nest-material), and food. Further analysis reveals that Red-crowned cranes have certain adaptability to the changes of nesting habitat quality in the Zhalong wetlands. In conclusion, fire, reeds,and water were the most important variables for nest-site habitat selection of Red-crowned Cranes in Zhalong Nature Reserve.

  17. Determinants of Brushite Stone Formation: A Case-Control Study

    OpenAIRE

    2013-01-01

    PURPOSE: The occurrence of brushite stones has increased during recent years. However, the pathogenic factors driving the development of brushite stones remain unclear. METHODS: Twenty-eight brushite stone formers and 28 age-, sex- and BMI-matched healthy individuals were enrolled in this case-control study. Anthropometric, clinical, 24 h urinary parameters and dietary intake from 7-day weighed food records were assessed. RESULTS: Pure brushite stones were present in 46% of patients, while ca...

  18. Chronic lymphocytic leukaemia: case control epidemiological study in Yorkshire.

    OpenAIRE

    Cartwright, R. A.; Bernard, S.M.; Bird, C. C.; Darwin, C. M.; O'Brien, C; Richards, I D; Roberts, B; McKinney, P A

    1987-01-01

    This is the second report of a large case control study of lymphoma/leukaemia occurring in Yorkshire during 1979-84, and deals with chronic lymphocytic leukaemia presenting either in its haematological (CLL) or more solid lymphomatous (malignant lymphoma-lymphocytic or MLL) forms. In all, 330 cases and 561 controls were interviewed. The results support the concept that CLL/MLL is a condition of multiple aetiologies with evidence for genetic predisposition through an excess of family cases, im...

  19. Non-Hodgkin's lymphoma: case control epidemiological study in Yorkshire.

    Science.gov (United States)

    Cartwright, R A; McKinney, P A; O'Brien, C; Richards, I D; Roberts, B; Lauder, I; Darwin, C M; Bernard, S M; Bird, C C

    1988-01-01

    This paper reports the results of a case control study of non-Hodgkin's lymphoma in the Yorkshire Health Region. In all, 437 cases and 724 controls were interviewed. Risk factors associated with past skin conditions, family history of cancer and infectious mononucleosis, aspects of social life and contact with wood dust and epoxy glues all emerge. A comparison of high and low grade morphological forms of disease reveal contrasting risks and suggest separate aetiologies for these conditions.

  20. Nested trampoline resonators for optomechanics

    Energy Technology Data Exchange (ETDEWEB)

    Weaver, M. J., E-mail: mweaver@physics.ucsb.edu; Pepper, B.; Luna, F.; Perock, B. [Department of Physics, University of California, Santa Barbara, California 93106 (United States); Buters, F. M.; Eerkens, H. J.; Welker, G.; Heeck, K.; Man, S. de [Huygens-Kamerlingh Onnes Laboratorium, Universiteit Leiden, 2333 CA Leiden (Netherlands); Bouwmeester, D. [Department of Physics, University of California, Santa Barbara, California 93106 (United States); Huygens-Kamerlingh Onnes Laboratorium, Universiteit Leiden, 2333 CA Leiden (Netherlands)

    2016-01-18

    Two major challenges in the development of optomechanical devices are achieving a low mechanical and optical loss rate and vibration isolation from the environment. We address both issues by fabricating trampoline resonators made from low pressure chemical vapor deposition Si{sub 3}N{sub 4} with a distributed Bragg reflector mirror. We design a nested double resonator structure with 80 dB of mechanical isolation from the mounting surface at the inner resonator frequency, and we demonstrate up to 45 dB of isolation at lower frequencies in agreement with the design. We reliably fabricate devices with mechanical quality factors of around 400 000 at room temperature. In addition, these devices were used to form optical cavities with finesse up to 181 000 ± 1000. These promising parameters will enable experiments in the quantum regime with macroscopic mechanical resonators.

  1. Nested Trampoline Resonators for Optomechanics

    CERN Document Server

    Weaver, Matthew J; Luna, Fernando; Buters, Frank M; Eerkens, Hedwig J; Welker, Gesa; Perock, Blaise; Heeck, Kier; de Man, Sven; Bouwmeester, Dirk

    2015-01-01

    Two major challenges in the development of optomechanical devices are achieving a low mechanical and optical loss rate and vibration isolation from the environment. We address both issues by fabricating novel trampoline resonators made from low pressure chemical vapor deposition (LPCVD) Si$_3$N$_4$ with a distributed bragg reflector (DBR) mirror. We construct a nested double resonator structure that generates approximately 80 dB of mechanical isolation from the mounting surface, eliminating the strong mounting dependence of the quality factor observed with single resonators. With the consistency provided by this isolation scheme we reliably fabricate devices with mechanical quality factors of around 400,000 at room temperature. In addition these devices were used to form optical cavities with finesse up to 181,000 $\\pm$ 1,000. These promising parameters will enable experiments in the quantum regime with macroscopic mechanical resonators.

  2. Assessment of global phase uncertainty in case-control studies

    Directory of Open Access Journals (Sweden)

    van Houwelingen Hans C

    2009-09-01

    Full Text Available Abstract Background In haplotype-based candidate gene studies a problem is that the genotype data are unphased, which results in haplotype ambiguity. The measure 1 quantifies haplotype predictability from genotype data. It is computed for each individual haplotype, and for a measure of global relative efficiency a minimum value is suggested. Alternatively, we developed methods directly based on the information content of haplotype frequency estimates to obtain global relative efficiency measures: and based on A- and D-optimality, respectively. All three methods are designed for single populations; they can be applied in cases only, controls only or the whole data. Therefore they are not necessarily optimal for haplotype testing in case-control studies. Results A new global relative efficiency measure was derived to maximize power of a simple test statistic that compares haplotype frequencies in cases and controls. Application to real data showed that our proposed method gave a clear and summarizing measure for the case-control study conducted. Additionally this measure might be used for selection of individuals, who have the highest potential for improving power by resolving phase ambiguity. Conclusion Instead of using relative efficiency measure for cases only, controls only or their combined data, we link uncertainty measure to case-control studies directly. Hence, our global efficiency measure might be useful to assess whether data are informative or have enough power for estimation of a specific haplotype risk.

  3. Methodology Series Module 2: Case-control Studies.

    Science.gov (United States)

    Setia, Maninder Singh

    2016-01-01

    Case-Control study design is a type of observational study. In this design, participants are selected for the study based on their outcome status. Thus, some participants have the outcome of interest (referred to as cases), whereas others do not have the outcome of interest (referred to as controls). The investigator then assesses the exposure in both these groups. The investigator should define the cases as specifically as possible. Sometimes, definition of a disease may be based on multiple criteria; thus, all these points should be explicitly stated in case definition. An important aspect of selecting a control is that they should be from the same 'study base' as that of the cases. We can select controls from a variety of groups. Some of them are: General population; relatives or friends; and hospital patients. Matching is often used in case-control control studies to ensure that the cases and controls are similar in certain characteristics, and it is a useful technique to increase the efficiency of the study. Case-Control studies can usually be conducted relatively faster and are inexpensive - particularly when compared with cohort studies (prospective). It is useful to study rare outcomes and outcomes with long latent periods. This design is not very useful to study rare exposures. Furthermore, they may also be prone to certain biases - selection bias and recall bias.

  4. The design and function of birds' nests.

    Science.gov (United States)

    Mainwaring, Mark C; Hartley, Ian R; Lambrechts, Marcel M; Deeming, D Charles

    2014-10-01

    All birds construct nests in which to lay eggs and/or raise offspring. Traditionally, it was thought that natural selection and the requirement to minimize the risk of predation determined the design of completed nests. However, it is becoming increasingly apparent that sexual selection also influences nest design. This is an important development as while species such as bowerbirds build structures that are extended phenotypic signals whose sole purpose is to attract a mate, nests contain eggs and/or offspring, thereby suggesting a direct trade-off between the conflicting requirements of natural and sexual selection. Nest design also varies adaptively in order to both minimize the detrimental effects of parasites and to create a suitable microclimate for parents and developing offspring in relation to predictable variation in environmental conditions. Our understanding of the design and function of birds' nests has increased considerably in recent years, and the evidence suggests that nests have four nonmutually exclusive functions. Consequently, we conclude that the design of birds' nests is far more sophisticated than previously realized and that nests are multifunctional structures that have important fitness consequences for the builder/s.

  5. Optimal Nesting for Continuous Shape Stamping Processes

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    This paper discusses the optimal nesting problem for minimizing the scrap in continuous shape stamping processes. The shape sliding technique is used to propose a new approach, OVERLAP-and-ESCAPE, to solve the problem of continuously nesting shapes onto a metal coil of fixed or selectable width. The approach is used to construct the objective function of the mathematical model of the problem using the Simulated Annealing Algorithm to determine the globally minimal configurations for the nesting problems. Some representative cases are studied and the results are encouraging. An automatic nesting software package for manufacturing bicycle chain link blanks is also described.

  6. Correlation between periodontal disease and onset of coronary heart disease: a Meta-analysis based on 37 case-control studies%牙周病与冠心病发病相关性:一项基于37个病例-对照研究的Meta分析

    Institute of Scientific and Technical Information of China (English)

    毛敏; 杨勇; 曾宪涛; 郭毅; 施俊; 李娟

    2012-01-01

    Objective To review the relationship between periodontal disease and onset risk of coronary heart disease ( CHD ) by using Meta-analysis method. Methods The case-control studies about the relationship between periodontal disease and onset risk of CHD were retrieved from PnbMed, Embase, China National Network Knowledge Infrastructure ( CNKI) , Chinese BioMedical Literature Database ( CBM ) , VIP Database and WanFang Database by two reviewers independently. The quality evaluation and data extraction were performed in the literature accorded with inclusion criterion by applying NOS standard, and then the Mate-analysis was conducted by using CMA v2 software. The level of evidence was graded by using GRADE system. Results There were totally 37 case-control studies included, and 18 in Chinese and 19 in English. The results of Meta-analysis showed that periodontal disease increased 3.76 times in the incidence of CHD ( OR=3.167 95%CI: 2.15-6.58, P<0.001 ) , and sensitivity analysis showed the results was stable. The results of subgroup analysis according to whether traditional risk factors were corrected showed that the incidence of CHD was still up to 2.78 times after correcting ( OR=2.78, 95%CI: 2.09-3.68, P<0.001 ) . The grade of evidence was low in GRADE system and publication bias was slight. Conclusion Periodontal disease is an independent and significant risk factor to CHD. More studies should be further conducted according to the clinical grading of periodontal disease and clinical subtypes of CHD.%目的 采用Meta分析的方法评价牙周病与冠心病(CHD)的发病风险关系.方法 由两名评价者独立检索PubMed、Embase、中国知网、中国生物医学文献数据库、维普及万方数据库中公开发表的探讨牙周炎与CHD发病风险关系病例-对照研究,对符合纳入标准的文献采用NOS标准进行质量评价、数据提取后采用CMA v2软件进行Meta分析,并采用GRADE系统进行证据评级.结果

  7. Nest distribution and nest habitat of the Tibetan Partridge (Perdix hodgsoniae) near Lhasa, Tibet

    Institute of Scientific and Technical Information of China (English)

    Tsering Dorge; Gran Hgstedt; Terje Lislevand

    2014-01-01

    Background:Little is hitherto known about the breeding ecology of the Tibetan Partridge (Perdix hodgsoniae) which is endemic to the Tibetan plateau. Here we describe nest densities, inter-nest distances and general nest site characteristics in this gallinaceous bird species and explore the possibilities that certain shrub and plant types are preferred as nest surroundings. Method:A total of 56 nests were found over three breeding seasons near Lhasa, Tibet. Nest site characteristics were compared with random control plots and the proportions of specific plant species covering nests were compared with their estimated general occurrence in the study area. Results:Nest density in the two years with highest search effort was estimated at 1.43/km2 and 1.04/km2 but was clearly higher in the part of the study area facing north (1.86–2.35/km2) than that facing south (0.11–0.34/km2). The average nearest neighbour distance of nests was about 300 m. Nests were situated in relatively lush vegetation and covered by a total of eight shrub species and three herbs. In contrast to previous reports, Caragana shrub did not constitute an important part of the nest habitat. The flowering, non-thorny bush Potentil a fruticosa was significantly over-represented as nest cover, while Rhododendron nivale was similarly under-represented. Nest bush foliage covered a larger area of ground, and the shrub surrounding nests was generally denser, than in control samples. Also, nests were placed closer to paths and in areas with lower densities of Yak (Bos grunniens) dung than in control samples. Except that soil temperatures were lower on nest sites than on control sites, micro-climate variables measured in this study did not differ between nest sites and control plots. Conclusions:Opportunity for nest concealment is probably an important quality of the nest habitat in Tibetan Partridges, yet it is unclear why the species should prefer P. fruticosa as nest cover. It is possible that nest sites

  8. Nest distribution and nest habitat of the Tibetan Partridge (Perdix hodgsoniae) near Lhasa, Tibet

    Institute of Scientific and Technical Information of China (English)

    Tsering; Dorge; G?ran; H?gstedt; Terje; Lislevand

    2014-01-01

    Background: Little is hitherto known about the breeding ecology of the Tibetan Partridge(Perdix hodgsoniae)which is endemic to the Tibetan plateau. Here we describe nest densities, inter-nest distances and general nest site characteristics in this gallinaceous bird species and explore the possibilities that certain shrub and plant types are preferred as nest surroundings.Method: A total of 56 nests were found over three breeding seasons near Lhasa, Tibet. Nest site characteristics were compared with random control plots and the proportions of specific plant species covering nests were compared with their estimated general occurrence in the study area.Results: Nest density in the two years with highest search effort was estimated at 1.43/km2 and 1.04/km2 but was clearly higher in the part of the study area facing north(1.86–2.35/km2) than that facing south(0.11–0.34/ km2). The average nearest neighbour distance of nests was about 300 m. Nests were situated in relatively lush vegetation and covered by a total of eight shrub species and three herbs. In contrast to previous reports, Caragana shrub did not constitute an important part of the nest habitat. The flowering, non-thorny bush Potentilla fruticosa was significantly over-represented as nest cover, while Rhododendron nivale was similarly under-represented. Nest bush foliage covered a larger area of ground, and the shrub surrounding nests was generally denser, than in control samples. Also, nests were placed closer to paths and in areas with lower densities of Yak(Bos grunniens) dung than in control samples.Except that soil temperatures were lower on nest sites than on control sites, micro-climate variables measured in this study did not differ between nest sites and control plots.Conclusions: Opportunity for nest concealment is probably an important quality of the nest habitat in Tibetan Partridges, yet it is unclear why the species should prefer P. fruticosa as nest cover. It is possible that nest sites are

  9. Does heavy physical exertion trigger myocardial infarction? A case-crossover analysis nested in a population-based case-referent study.

    Science.gov (United States)

    Hallqvist, J; Möller, J; Ahlbom, A; Diderichsen, F; Reuterwall, C; de Faire, U

    2000-03-01

    To study possible triggering of first events of acute myocardial infarction by heavy physical exertion, the authors conducted a case-crossover analysis (1993-1994) within a population-based case-referent study in Stockholm County, Sweden (the Stockholm Heart Epidemiology Program). Interviews were carried out with 699 myocardial infarction patients after onset of the disease. These cases represented 47 percent of all cases in the study base, and 70 percent of all nonfatal cases. The relative risk from vigorous exertion was 6.1 (95% confidence interval: 4.2, 9.0). The rate difference was 1.5 per million person-hours, and the attributable proportion was 5.7 percent. The risk was modified by physical fitness, with an increased risk being seen among sedentary subjects as in earlier studies, but the data also suggested a U-shaped association. In addition, the trigger effect was modified by socioeconomic status. Premonitory symptoms were common, and this implies risks of reverse causation bias and misclassification of case exposure information that require methodological consideration. Different techniques (the use of the usual-frequency type of control information, a pair-matched analysis, and a standard case-referent analysis) were applied to overcome the threat of misclassification of control exposure information. A case-crossover analysis in a random sample of healthy subjects resulted in a relative risk close to unity, as expected.

  10. Birds' nesting parameters in four forest types in the Pantanal wetland.

    Science.gov (United States)

    Pinho, J B; Marini, M A

    2014-11-01

    We tested the heterogeneity/productivity hypothesis with respect to the abundance and richness of birds and the vegetation density hypothesis with respect to birds' nest predation rates, and determined the relative importance of forested vegetation formations for the conservation of birds in the Pantanal. We estimated the apparent nesting success, and the abundance and richness of nesting birds' in four forest types, by monitoring nests during two reproductive seasons in four forested physiognomies (two high productivity/heterogeneity evergreen forests = Cambará and Landi; two low productivity/heterogeneity dry forests = Cordilheira and Carvoeiro) in the Pantanal wetland in Poconé, State of Mato Grosso, Brazil. We found 381 nests of 46 species (35 Passeriformes and 11 non-Passeriformes) in the four forest types. Of these, we monitored 220 active nests belonging to 44 species, 101 during the reproductive season of 2001 and 119 in 2002. We supported the productivity/heterogeneity hypothesis since the two evergreen forests had higher nest abundance and one of them (Cambará) had higher nesting species richness than the dry forests. The number of nests found in each habitat differed with most nests monitored in the Cambará forest (82%), followed by Landi (9%), Cordilheira (6%) and Carvoeiro (3%) forests. The total number of nests monitored was significantly higher in evergreen forests than in dry forests. Also, more species nested in evergreen (37 species) than in dry (16 species) forests. A Correspondence Analysis revealed that only Carvoeiros had a different nesting bird community. The overall apparent nesting success of 220 nests was 26.8%. We did not support the vegetation density hypothesis since nest predation rates were similar between evergreen (73.5%) and dry (70%) forests, and were higher in the Landi (85%) than in the other three forests (69.2 to 72.2%). Our data indicate that Cambará forests seem to be a key nesting habitat for many bird species of the

  11. Interaction and Its Solution in Individual Matching Case-control Study

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Objective To indicate the deficiency of the classical method for analyzing data on individual matching case-control study in consideration of the interaction between the study factor (exposure) and the matching factor, and to find out a proper method for handling this deficiency. Method First, experimental data with 50 pairs of cases and controls were used for strata analysis according to the values of a matching factor to illustrate the possible interaction between a risk factor (exposure) and the matching factor. Second, a detailed procedure was proposed for analyzing such data. Results Interaction between the study factor and matching factor was demonstrated by using strata analysis and unconditional logistic regression analysis. Therefore the results from the classical analysis for such data might be incorrect. Conclusion Data from individual matching case-control study design should be dealt with strata analysis or multivariate analysis to explore and evaluate the possible interaction between the study factor and matching factor. The conclusion would be valid only after such analysis is conducted.

  12. Adipokines as Possible New Predictors of Cardiovascular Diseases: A Case Control Study

    Directory of Open Access Journals (Sweden)

    Laura Pala

    2012-01-01

    Full Text Available Background and Aims. The secretion of several adipocytokines, such as adiponectin, retinol-binding protein 4 (RBP4, adipocyte fatty acid binding protein (aFABP, and visfatin, is altered in subjects with abdominal adiposity; these endocrine alterations could contribute to increased cardiovascular risk. The aim of the study was to assess the relationship among adiponectin, RBP4, aFABP, and visfatin, and incident cardiovascular disease. Methods and Results. A case-control study, nested within a prospective cohort, on 2945 subjects enrolled for a diabetes screening program was performed. We studied 18 patients with incident fatal or nonfatal IHD (Ischemic Heart Disease or CVD (Cerebrovascular Disease, compared with 18 matched control subjects. Circulating adiponectin levels were significantly lower in cases of IHD with respect to controls. Circulating RBP4 levels were significantly increased in CVD and decreased in IHD with respect to controls. Circulating aFABP4 levels were significantly increased in CVD, while no difference was associated with IHD. Circulating visfatin levels were significantly lower in cases of both CVD and IHD with respect to controls, while no difference was associated with CVD. Conclusions. The present study confirms that low adiponectin is associated with increased incidents of IHD, but not CVD, and suggests, for the first time, a major effect of visfatin, aFABP, and RBP4 in the development of cardiovascular disease.

  13. Correlation between periodontal disease and onset of rheumatoid arthritis:a Meta-analysis of case-control studies%牙周病与类风湿性关节炎相关性的病例-对照研究的 Meta 分析

    Institute of Scientific and Technical Information of China (English)

    席晨希; 周群; 罗敏

    2015-01-01

    目的:采用 Meta 分析的方法评价牙周病(PD)与类风湿性关节炎(RA)的发病风险关系。方法计算机检索PubMed、EMbase、中国生物医学文献数据库、中国知网、维普及万方数据库,查找国内外公开发表关于 PD 与 RA 发病风险关系的病例-对照研究,检索时限均为从建库至2014年5月20日,同时追溯纳入文献的参考文献。由2位研究者根据纳入与排除标准独立选择文献、提取资料和质量评价后,采用 CMA v2软件进行 Meta 分析。结果最终共纳入9个病例-对照研究,2篇中文文献,7篇英文文献,其中 RA 组465例,健康对照组421例。Meta 分析结果显示暴露于 PD 可以显著提高 RA 发生率2.81倍[OR =2.81,95%CI(1.41~5.60),P =0.003],敏感性分析显示结果稳健性较好。无明显发表偏倚存在。结论PD是 RA 的一个有意义的危险因子。应进一步进行按 PD 临床程度分级和 RA 临床亚型分型的研究。%Objective To investigate the relationship between periodontal disease (PD)and risk of rheumatoid arthritis (RA)by performing a meta-analysis.Methods Such databases as PubMed,EMbase,CBM,CNKI,and WanFang databases were searched from their inception to May 20th,2014 to collect case-control studies about the PD and risk of RA,and the relevant references of the included literature were also retrieved.Two reviewers independently screened the literature according to the inclusion and exclusion criteria,ex-tracted the data,and assessed the methodological quality.Then meta-analysis was conducted using CMA v2 software.Results Eventu-ally nine case-control studies were included,2 in Chinese literature,7 articles in English literature,including RA group 465 cases and 421 cases of normal control group.The meta-analysis showed that exposure to PD could obviously increase incidence of rheumatoid ar-thritis 2.81 times (OR =2.81 ,95% CI 1 .41 to 5.60,P =0.003),and

  14. 1989 Waterfowl Nesting Study and Nesting Summary 1984-1989 : Big Stone National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The 1989 nesting season marked the sixth consecutive and final year that Big Stone personnel have conducted waterfowl nesting research. In addition, an experimental...

  15. Florida harvester ant nest architecture, nest relocation and soil carbon dioxide gradients.

    Science.gov (United States)

    Tschinkel, Walter R

    2013-01-01

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

  16. Aromatic Plants in Eurasian Blue Tit Nests: The ‘Nest

    OpenAIRE

    Pires, Bárbara A.; Anabela F. Belo; Rabaça, João E.

    2012-01-01

    The ‘Nest Protection Hypothesis’ suggests that some birds add aromatic plants to their nests to repel or kill ectoparasites. This behavior has been described for several species, including the Eurasian Blue Tit (Cyanistes caeruleus). We studied the reproductive performance, based on 26 nests (in nest boxes), of this species in mixed forested areas of Quercus spp. and Pinus pinea in the Parque Florestal de Monsanto, the largest park of Lisbon, Portugal. The frequency of aromatic plant...

  17. Nest survival is influenced by parental behaviour and heterospecifics in a mixed-species colony

    Science.gov (United States)

    Brussee, Brianne E.; Coates, Peter S.; Hothem, Roger L.; Howe, Kristy; Casazza, Michael L.; Eadie, John M.

    2016-01-01

    Studies of avian nest success often focus on examining influences of variation in environmental and seasonal factors. However, in-depth evaluations can also incorporate variation in individual incubation behaviour to further advance our understanding of avian reproductive ecology. We examined these relationships in colonially nesting Black-crowned Night-Herons Nycticorax nycticorax using intensive video-monitoring methods to quantify incubation behaviours. We modelled nest survival as a function of both extrinsic factors and incubation behaviours over a 3-year period (2010–12) on Alcatraz Island, USA. Model-averaged parameter estimates indicated that nest survival increased as a function of greater incubation constancy (% of time spent incubating eggs within a 24-h period), and average daily precipitation throughout the nesting stage. Common Ravens Corvus corax are the only known nest predator of Night-Herons on Alcatraz Island, as on many other coastal Pacific islands. We also investigated the effects of heterospecific nesting of California Gulls Larus californicus and Western Gulls Larus occidentalis in a mixed-species colony with Night-Herons, based on nesting proximity data collected over a 2-year period (2011–12). This second analysis indicated that, in addition to incubation behaviours, nesting heterospecifics are an important factor for explaining variation in Night-Heron nest survival. However, contrary to our original expectation, we found that Night-Herons experienced increased nest survival with increasing distance from gull colony boundaries. These results may apply to other areas with multiple colonial nesting species and similar predator communities and climatic patterns.

  18. 7 CFR 29.6027 - Nested.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Nested. 29.6027 Section 29.6027 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... INSPECTION Standards Definitions § 29.6027 Nested. Any tobacco which has been loaded, packed, or arranged...

  19. Dune vegetation fertilization by nesting sea turtles.

    Science.gov (United States)

    Hannan, Laura B; Roth, James D; Ehrhart, Llewellyn M; Weishampel, John F

    2007-04-01

    Sea turtle nesting presents a potential pathway to subsidize nutrient-poor dune ecosystems, which provide the nesting habitat for sea turtles. To assess whether this positive feedback between dune plants and turtle nests exists, we measured N concentration and delta15N values in dune soils, leaves from a common dune plant (sea oats [Uniola paniculata]), and addled eggs of loggerhead (Caretta caretta) and green turtles (Chelonia mydas) across a nesting gradient (200-1050 nests/km) along a 40.5-km stretch of beach in east central Florida, USA. The delta15N levels were higher in loggerhead than green turtle eggs, denoting the higher trophic level of loggerhead turtles. Soil N concentration and delta15N values were both positively correlated to turtle nest density. Sea oat leaf tissue delta15N was also positively correlated to nest density, indicating an increased use of augmented marine-based nutrient sources. Foliar N concentration was correlated with delta15N, suggesting that increased nutrient availability from this biogenic vector may enhance the vigor of dune vegetation, promoting dune stabilization and preserving sea turtle nesting habitat.

  20. Waterbird nest-site selection is influenced by neighboring nests and island topography

    Science.gov (United States)

    Hartman, Christopher; Ackerman, Josh; Takekawa, John Y.; Herzog, Mark

    2016-01-01

    Avian nest-site selection is influenced by factors operating across multiple spatial scales. Identifying preferred physical characteristics (e.g., topography, vegetation structure) can inform managers to improve nesting habitat suitability. However, social factors (e.g., attraction, territoriality, competition) can complicate understanding physical characteristics preferred by nesting birds. We simultaneously evaluated the physical characteristics and social factors influencing selection of island nest sites by colonial-nesting American avocets (Recurvirostra americana) and Forster's terns (Sterna forsteri) at 2 spatial scales in San Francisco Bay, 2011–2012. At the larger island plot (1 m2) scale, we used real-time kinematics to produce detailed topographies of nesting islands and map the distribution of nests. Nesting probability was greatest in island plots between 0.5 m and 1.5 m above the water surface, at distances less likely to nest in plots adjacent to plots with nesting avocets, suggesting an influence of intra-specific territoriality. At the smaller microhabitat scale, or the area immediately surrounding the nest, we compared topography, vegetation, and distance to nearest nest between nest sites and paired random sites. Topography had little influence on selection of the nest microhabitat. Instead, nest sites were more likely to have vegetation present, and greater cover, than random sites. Finally, avocet, and to a lesser extent tern, nest sites were closer to other active conspecific or heterospecific nests than random sites, indicating that social attraction played a role in selection of nest microhabitat. Our results demonstrate key differences in nest-site selection between co-occurring avocets and terns, and indicate the effects of physical characteristics and social factors on selection of nesting habitat are dependent on the spatial scale examined. Moreover, these results indicate that islands with abundant area between 0.5 m and 1.5

  1. Conservation significance of alternative nests of golden eagles

    Directory of Open Access Journals (Sweden)

    Brian A. Millsap

    2015-01-01

    Full Text Available Golden eagles (Aquila chrysaetos are long-lived raptors that maintain nesting territories that may be occupied for a century or longer. Within occupied nesting territories there is one nest in which eagles lay their eggs in a given year (i.e., the used nest, but there are usually other nests (i.e., alternative nests. Conservation plans often protect used nests, but not alternative nests or nesting territories that appear vacant. Our objective is to review literature on golden eagle use of alternative nests and occupancy of nesting territories to determine if alternative nests are biologically significant and warrant greater conservation consideration. Our review shows that: (1 alternative nests or their associated habitat are most often in core areas of golden eagle nesting territories; (2 alternative nests likely will become used in the future; (3 probability of an alternative nest becoming used is greatest where prey availability is high and alternative nest sites are limited; (4 likelihood of annual occupancy or reoccupancy of golden eagle nesting territories is high; and (5 prey availability is the most important determinant of nesting territory occupancy and breeding activity. We recommend alternative nests be treated with the same deference as used nests in land use planning.

  2. Ventilation and dampness in dorms and their associations with allergy among college students in China: a case-control study

    DEFF Research Database (Denmark)

    Sun, Y; Zhang, Y; Bao, L;

    2011-01-01

    the case in developing countries like China, where dorms tend to be more crowded. In dorms, a low ventilation rate is a risk factor for asthma and allergy. Sufficient fresh outdoor air should be provided to students' dormitories by controlled ventilation. Mechanical ventilation system are often needed......Abstract To study the associations between dorm environment and occupants' health, a nested case-control study on 348 college students was carried out in 2006-2007 at Tianjin University, China. Two hundred and twenty-three dorm rooms where the 'cases' and 'controls' resided were inspected. Measured...... variables were ventilation rate, air temperature, and relative humidity indoors. Allergic symptoms in the last 12 months were self-reported by occupants. Adjusted odds ratios (AORs) of a 'localized moldy smell/moisture indicator' in 'special places' (e.g., in a room corner or close to the radiator under...

  3. Chronic lymphocytic leukaemia: case control epidemiological study in Yorkshire.

    Science.gov (United States)

    Cartwright, R A; Bernard, S M; Bird, C C; Darwin, C M; O'Brien, C; Richards, I D; Roberts, B; McKinney, P A

    1987-07-01

    This is the second report of a large case control study of lymphoma/leukaemia occurring in Yorkshire during 1979-84, and deals with chronic lymphocytic leukaemia presenting either in its haematological (CLL) or more solid lymphomatous (malignant lymphoma-lymphocytic or MLL) forms. In all, 330 cases and 561 controls were interviewed. The results support the concept that CLL/MLL is a condition of multiple aetiologies with evidence for genetic predisposition through an excess of family cases, immune perturbation demonstrated by excessive previous skin diseases and phenylbutazone use, and viral involvement shown by links with infectious diseases and multiple sclerosis.

  4. Struggling doctors in specialist training: a case control study

    DEFF Research Database (Denmark)

    O'Neill, Lotte; Norberg, Karen; Thomsen, Maria

    between medical student behaviours and performances and subsequent professional misconduct or disciplinary action with the same study design and found positive associations.4,7 Our results (positive or negative) is of importance in the general discussion of the transition and handing-over of medical......, James D. Risk factors at medical school for subsequent professional misconduct: multicenter retrospective case-control study. BMJ 2010;340:c2040. Evans DE, Alstead EM, Brown J. Applying your clinical skills to students and trainees in academic difficulty. Clin Teach 2010;7(4):230-235. Yao DC, Wright SM...

  5. Nesting Ecology of Hawksbill Sea Turtles (Eretmochelys imbricata) on Utila, Honduras

    Science.gov (United States)

    Damazo, Lindsey Renee Eggers

    The hawksbill sea turtle (Eretmochelys imbricata) has a circumtropical distribution and plays an important role in maintaining the health of coral reefs. Unfortunately, hawksbill populations have been decimated, and estimated numbers in the Caribbean are less than 10% of populations a century ago. The hawksbill is considered Critically Endangered, and researchers are coordinating worldwide efforts to protect this species. One country where we lack knowledge regarding hawksbills is Honduras. This study aimed to increase our understanding of hawksbill nesting ecology in Caribbean Honduras. Characteristics of hawksbill nesting activity and a nesting beach on the island of Utila were elucidated using satellite telemetry, beach profiling, vegetation surveys, beach monitoring, and nest temperature profiles. We affixed satellite transmitters to two nesting hawksbills, and found the turtles migrated to different countries. One turtle traveled 403 km to a bay in Mexico, and the other traveled 181 km to a Marine Protected Area off Belize. This study presents the first description of hawksbill migration routes from Honduras, facilitating protection efforts for turtles that traverse international waters. To investigate nesting beach and turtle characteristics, we conducted beach monitoring during the 2012 nesting season. Nesting turtle carapace sizes were similar to worldwide values, but hatchlings were heavier. To measure nest temperatures, we placed thermocouple data loggers in four nests and four pseudo-nests. Data suggested metabolic heating may be maintaining nest temperatures above the pivotal temperature. However, large temperature fluctuations corresponding to rainfall from Hurricane Ernesto (as determined using a time series cross-correlation analysis) make it difficult to predict sex ratios, and underscore the impact stochastic events can have on nest temperatures. We created topographic and substrate profiles of the beach, and found it was 475 m long, yet hawksbills

  6. Interaction between genetic and environmental risk factors for Alzheimer's disease: A reanalysis of case-control studies

    NARCIS (Netherlands)

    C.M. van Duijn (Cock); D.G. Clayton (David); V. Chandra; L. Fratiglioni (Laura); A.B. Graves; A. Heyman; A.F. Jorm; E. Kokmen (Emre); K. Kondo; J.A. Mortimer; W.A. Rocca (Walter); S.L. Shalat; H. Soininen (H.); A. Hofman (Albert)

    1994-01-01

    textabstractTo study the interaction among genetic and environmental risk factors, a reanalysis of case-control studies of Alzheimer's disease (AD) was conducted based on the original data of all studies carried out to January 1, 1990. Seven studies were included in the present analysis, comprising

  7. CAPL: a novel association test using case-control and family data and accounting for population stratification.

    Science.gov (United States)

    Chung, Ren-Hua; Schmidt, Michael A; Morris, Richard W; Martin, Eden R

    2010-11-01

    The recent successes of GWAS based on large sample sizes motivate combining independent datasets to obtain larger sample sizes and thereby increase statistical power. Analysis methods that can accommodate different study designs, such as family-based and case-control designs, are of general interest. However, population stratification can cause spurious association for population-based association analyses. For family-based association analysis that infers missing parental genotypes based on the allele frequencies estimated in the entire sample, the parental mating-type probabilities may not be correctly estimated in the presence of population stratification. Therefore, any approach to combining family and case-control data should also properly account for population stratification. Although several methods have been proposed to accommodate family-based and case-control data, all have restrictions. Most of them require sampling a homogeneous population, which may not be a reasonable assumption for data from a large consortium. One of the methods, FamCC, can account for population stratification and uses nuclear families with arbitrary number of siblings but requires parental genotype data, which are often unavailable for late-onset diseases. We extended the family-based test, Association in the Presence of Linkage (APL), to combine family and case-control data (CAPL). CAPL can accommodate case-control data and families with multiple affected siblings and missing parents in the presence of population stratification. We used simulations to demonstrate that CAPL is a valid test either in a homogeneous population or in the presence of population stratification. We also showed that CAPL can have more power than other methods that combine family and case-control data.

  8. Urine Nested Polymerase Chain Reaction in Neonatal Septicemia.

    Science.gov (United States)

    Das, B K; Suri, Shipra; Nath, Gopal; Prasad, Rajniti

    2015-08-01

    This cross-sectional study was done to evaluate diagnostic efficacy of urine nested polymerase chain reaction (PCR) using broad-range 16SrDNA PCR-based amplification, followed by restriction analysis and sequencing in neonatal septicemia. The study included 50 babies; 48% had vaginal delivery, 46% were preterm, 20% had a history of prolonged rupture of membranes and 56% were low birth weight (≤2500 g). Clinical presentations were lethargy (96%), respiratory distress (80%) and bleeding diathesis (16%). Absolute neutrophil count <1800/mm(3) was observed in 60%, and positive C-reactive protein in 46%. Thirty neonates had positive blood culture, and Klebsiella pneumoniae (22%) was the predominant organism. Nested urine PCR was positive in 38 (76%) and detected bacterial DNA in 8 neonates with negative blood cultures. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of nested PCR were 100, 60, 78.9, 100 and 84%, respectively, compared with blood culture. Nested PCR can detect most bacteria in single assay and identify unusual and unexpected causal agents.

  9. Lesser prairie-chicken nest site selection, microclimate, and nest survival in association with vegetation response to a grassland restoration program

    Science.gov (United States)

    Boal, Clint W.; Grisham, Blake A.; Haukos, David A.; Zavaleta, Jennifer C.; Dixon, Charles

    2014-01-01

    Climate models predict that the region of the Great Plains Landscape Conservation Cooperative (GPLCC) will experience increased maximum and minimum temperatures, reduced frequency but greater intensity of precipitation events, and earlier springs. These climate changes along with different landscape management techniques may influence the persistence of the lesser prairie-chicken (Tympanuchus pallidicinctus), a candidate for protection under the Endangered Species Act and a priority species under the GPLCC, in positive or negative ways. The objectives of this study were to conduct (1) a literature review of lesser prairie-chicken nesting phenology and ecology, (2) an analysis of thermal aspects of lesser prairie-chicken nest microclimate data, and (3) an analysis of nest site selection, nest survival, and vegetation response to 10 years of tebuthiuron and/or grazing treatments. We found few reports in the literature containing useful data on the nesting phenology of lesser prairie-chickens; therefore, managers must rely on short-term observations and measurements of parameters that provide some predictive insight into climate impacts on nesting ecology. Our field studies showed that prairie-chickens on nests were able to maintain relatively consistent average nest temperature of 31 °C and nest humidities of 56.8 percent whereas average external temperatures (20.3–35.0 °C) and humidities (35.2–74.9 percent) varied widely throughout the 24 hour (hr) cycle. Grazing and herbicide treatments within our experimental areas were designed to be less intensive than in common practice. We determined nest locations by radio-tagging hen lesser prairie-chickens captured at leks, which are display grounds at which male lesser prairie-chickens aggregate and attempt to attract a female for mating. Because nest locations selected by hen lesser prairie-chicken are strongly associated with the lek at which they were captured, we assessed nesting habitat use on the basis of hens

  10. Olive ridley sea turtle hatching success as a function of the microbial abundance in nest sand at Ostional, Costa Rica.

    Directory of Open Access Journals (Sweden)

    Vanessa S Bézy

    Full Text Available Several studies have suggested that significant embryo mortality is caused by microbes, while high microbial loads are generated by the decomposition of eggs broken by later nesting turtles. This occurs commonly when nesting density is high, especially during mass nesting events (arribadas. However, no previous research has directly quantified microbial abundance and the associated effects on sea turtle hatching success at a nesting beach. The aim of this study was to test the hypothesis that the microbial abundance in olive ridley sea turtle nest sand affects the hatching success at Ostional, Costa Rica. We applied experimental treatments to alter the microbial abundance within the sand into which nests were relocated. We monitored temperature, oxygen, and organic matter content throughout the incubation period and quantified the microbial abundance within the nest sand using a quantitative polymerase chain reaction (qPCR molecular analysis. The most successful treatment in increasing hatching success was the removal and replacement of nest sand. We found a negative correlation between hatching success and fungal abundance (fungal 18S rRNA gene copies g(-1 nest sand. Of secondary importance in determining hatching success was the abundance of bacteria (bacterial 16S rRNA gene copies g(-1 g(-1 nest sand. Our data are consistent with the hypothesis that high microbial activity is responsible for the lower hatching success observed at Ostional beach. Furthermore, the underlying mechanism appears to be the deprivation of oxygen and exposure to higher temperatures resulting from microbial decomposition in the nest.

  11. Emperor penguins nesting on Inaccessible Island

    Science.gov (United States)

    Jonkel, G.M.; Llano, G.A.

    1975-01-01

    Emperor penguins were observed nesting on Inaccessible I. during the 1973 winter. This is the southernmost nesting of emperor penguins thus far recorded; it also could be the first record of emperors attempting to start a new rookery. This site, however, may have been used by emperors in the past. The closest reported nesting of these penguins to Inaccessible I. is on the Ross Ice Shelf east of Cape Crozier. With the exception of the Inaccessible I. record, there is little evidence that emperor penguins breed in McMurdo Sound proper.

  12. Dinosaurs nesting on a red beach?

    Science.gov (United States)

    Sander, P. Martin; Peitz, Christian; Gallemi, Jaume; Cousin, Rémi

    1998-07-01

    The Upper Cretaceous Basturs locality (Tremp Basin, northern Spain) preserves numerous dinosaur eggs ( Megaloolithus cf. M. mammilare Vianey-Liaud, 1994). The locality was recently studied by Sanz et al. (1995) as well as by us. However, we have to disagree with several conclusions by Sanz et al. and suggest alternative interpretations incorporating data from other localities (Coll de Nargó). The dinosaurs at Basturs did not nest at the beach, nor is there evidence for colonial nesting and territorial behaviour. However, the locality superbly documents nesting site fidelity with an estimated occupation time of over 10 000 years.

  13. 1988 Duck nesting study: Stillwater Wildlife Management Area

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — During the summer, 1988, we conducted a duck nesting study to determine nest success for ducks at Stillwater Wildlife Management Area (WMA). We calculated nest...

  14. Ant colonies prefer infected over uninfected nest sites

    DEFF Research Database (Denmark)

    Pontieri, Luigi; Vojvodic, Svjetlana; Graham, Riley

    2014-01-01

    and low genetic diversity, likely making these species particularly vulnerable to parasites and diseases. We investigated the nest site preference of the invasive pharaoh ant, Monomorium pharaonis, through binary choice tests between three nest types: nests containing dead nestmates overgrown...

  15. Spatial dynamics of nesting behavior: lizards shift microhabitats to construct nests with beneficial thermal properties.

    Science.gov (United States)

    Angilletta, Michael J; Sears, Michael W; Pringle, Robert M

    2009-10-01

    Because temperature affects the growth, development, and survival of embryos, oviparous mothers should discriminate carefully among available nesting sites. We combined a radiotelemetric study of animal movements with a spatial mapping of environmental temperatures to test predictions about the nesting behavior of the eastern fence lizard (Sceloporus undulatus). Females made large excursions from their typical home ranges to construct nests in exposed substrates. These excursions appeared to be related solely to nesting because all females returned to forested habitat immediately afterward. On average, <1% (range = 0-8%, n = 19) of the area used by a female during nesting was contained within the area used before and after nesting. The selection of nesting sites matched predictions based on laboratory studies of embryonic performance; specifically, females nested in extremely open habitat at a mean of 6 cm depth. Spatial mapping of soil temperatures revealed that temperatures of nesting areas exceeded those of areas typically used by females, indicating that females preferred to construct warm nests that speed embryonic growth and development. However, this behavior could reduce the survivorship of females because of the need to rapidly navigate unfamiliar and exposed terrain.

  16. The nest as fortress: Defensive behavior of Polybia emaciata, a mud-nesting eusocial wasp

    Directory of Open Access Journals (Sweden)

    Sean O'Donnell

    2002-02-01

    Full Text Available The swarm-founding wasp Polybia emaciata is unusual among eusocial Vespidae because it uses mud, rather than wood pulp, as its primary nest construction material. Polybia emaciata nests are more durable than similarly sized paper nests. We tested the hypothesis that the defensive behavior of this wasp may have been modified to take advantage of their strong nests in defense against vertebrate attacks. We simulated vertebrate disturbances by tapping on, and breathing in, P. emaciata. nests and similarly sized P. occidentalis paper nests in the same location at the same time. Polybia emaciata. responses to disturbance were qualitatively different from those of P. occidentalis. The latter exit the nest and attack, while P. emaciata. workers typically fled or entered the nest, attacking only after repeated and extended disturbances. We conclude that durable nest material may permit predator avoidance behavior in P. emaciata.. We compare the defensive responses of P. emaciata. workers with those of other swarm-founding Vespidae, and discuss several selective forces that could cause the evolution of species variation in nest defense behavior.

  17. Nest site characteristics and nesting success of the Western Burrowing Owl in the eastern Mojave Desert

    Science.gov (United States)

    Longshore, Kathleen M.; Crowe, Dorothy E.

    2013-01-01

    We evaluated nest site selection at two spatial scales (microsite, territory) and reproductive success of Western Burrowing Owls (Athene cunicularia hypugaea) at three spatial scales (microsite, territory, landscape) in the eastern Mojave Desert. We used binary logistic regression within an information-theoretic approach to assess factors influencing nest site choice and nesting success. Microsite-scale variables favored by owls included burrows excavated by desert tortoise (Gopherus agassizii), burrows with a large mound of excavated soil at the entrance, and a greater number of satellite burrows within 5 m of the nest burrow. At the territory scale, owls preferred patches with greater cover of creosote bush (Larrea tridentata) within 50 m of the nest burrow. An interaction between the presence or absence of a calcic soil horizon layer over the top of the burrow (microsite) and the number of burrows within 50 m (territory) influenced nest site choice. Nesting success was influenced by a greater number of burrows within 5 m of the nest burrow. Total cool season precipitation was a predictor of nesting success at the landscape scale. Conservation strategies can rely on management of habitat for favored and productive nesting sites for this declining species.

  18. Relative effects of plumage coloration and vegetation density on nest success

    Science.gov (United States)

    Miller, M.W.

    1999-01-01

    Many passerine species are highly dichromatic with brightly-colored males and cryptically-colored females. Bright plumage in males is commonly thought to arise as a result of sexual selection by females such that males with bright coloration possess high fitness. However, bright plumage potentially could expose males to increased predation risk. Consistent with this idea, males of many highly dichromatic passerine species do not incubate. I tested whether brightly-colored males avoid incubation to reduce the probability of visual predators locating their nest. This hypothesis predicts greater hatching success for clutches incubated by cryptically-colored individuals than by brightly-colored individuals. The Northern Cardinal (Cardinalis cardinalis) is a common dichromatic species that breeds throughout the eastern U.S. I placed two button-quail (Turnix st).) eggs in each of 203 simulated cardinal nests. Dull brown cardboard, simulating a female cardinal, was placed over about half of all clutches. Bright red cardboard, simulating a male cardinal, was placed over the other clutches. Nest success was highest for well-concealed nests (87%) and lowest for nests in open habitat (54%). Nests containing red cardboard did not have significantly lower success than nests with brown cardboard, nor did I detect a significant color X vegetation-density interaction. My analysis may have had insufficient power to detect an effect of color on nest success; alternatively, brightly-colored males that do not incubate may achieve benefits unrelated to predation risk.

  19. Marbled Murrelets Select Distinctive Nest Trees within Old-Growth Forest Patches

    Directory of Open Access Journals (Sweden)

    Michael P. Silvergieter

    2011-12-01

    Full Text Available The coastal old-growth forests of North America's Pacific Coast are renowned both for their commercial and ecological value. This study adds to growing evidence that selective harvesting of the largest trees may have a disproportionate ecological impact. Marbled Murrelets (Brachyramphus marmoratus, a threatened species, nest almost exclusively in these old-growth forests. Detailed knowledge of nesting habitat selection provides guidance for habitat management and conservation. Habitat selection for this species has been studied at a variety of scales using ground and remote methods. However, because Marbled Murrelet nesting activity is limited to a single mossy platform on a single tree, we investigated nest tree selection within old-growth forest patches, using a set of 59 forest patches containing active nests. Nest trees were usually distinctive compared with neighboring trees in the surrounding 25 m radius patch. They averaged 15 to 20% taller than neighboring trees depending on region, had significantly larger stem diameters, more potential nesting platforms, and more moss. They had the most extreme values of height and width about three times as often as expected by chance. An analysis of moss platform use as a function of number of platforms per platform tree suggests that murrelets select individual platforms, rather than platform trees per se. Nonetheless, highly selective logging practices that remove high-value trees from stands may also remove trees most likely to be selected by nesting murrelets.

  20. Rheumatoid Arthritis - Neuropsychology, Depression and Anxiety. A case - control study -120 Portuguese Female subjects.

    Directory of Open Access Journals (Sweden)

    Luis Maia

    2012-07-01

    Full Text Available Objectives: Impact of Rheumatoid Arthritis in cognitive functions has not been well acknowledged in Portugal. With this original article we intended to elucidate this problem in this specific country. Methods: We measured the results of 60 Rheumatoid Arthritis female patients (study group, comparing every patient in a case control paired plan (years in school and age, with control subjects (n = 60, in a total of 120 subjects. All participants were evaluated with Paced Auditory Selective Attention Test, Word List Generation Test, Luria Nebraska Neuropsychological Battery, a Portuguese depressive screening test (IACLIDE, STAI (anxiety trace and trait test and the Mini Mental state examination.Results: The outcomes demonstrate, for the first conclusive time in Portuguese patients, the occurrence of main deficits in terms of cognitive functioning (measured by a variety ofneuropsychological tests, and depressive and anxietysymptomatology. Conclusion: This article asset the need to pay attention in psychoeducational, psychotherapeutic and cognitive stimulation, and reinforcement of neuropsychological intervention in these types of patients.Objectivos: O impacto da artrite reumatóide nas funçõescognitivas não tem sido bem reconhecido em Portugal. Com este artigo original pretendemos elucidar este problema neste país específico.Métodos: Avaliámos os resultados de 60 pacientes femininos com artrite reumatóide (grupo de estudo, comparando cada paciente num estudo de caso-controle, emparelhando ossujeitos com Artrite Reumatóide (60 sujeitos com 60 pacientes Artrite Reumatóide, nas variáveis anos de escolaridade eidade (a variável género era uma constante = feminino.Todos os participantes foram avaliados com o Teste de Atenção Auditiva Selectiva (PASAT, teste de geração de lista de palavras, Bateria Neuropsicológica de Luria Nebraska, um teste português de despistagem de sintomatologia depressiva (IACLIDE, um teste de rastreamento de tra

  1. Metabolic Derangements in Lichen Planus - A Case Control Study

    Science.gov (United States)

    Kar, Bikash Ranjan; Panda, Maitreyee

    2016-01-01

    Introduction An association between psoriasis and metabolic syndrome has been established in previous studies. Lichen Planus (LP) is also a chronic inflammatory disease morphologically related to psoriasis and few studies have shown association of metabolic derangements in LP. Aim To study the association of metabolic derangements in LP. Materials and Methods A prospective case control study was undertaken for a period of one year. Age and sex matched patients of LP and other non-inflammatory diseases were taken as cases and controls respectively. Data on height, weight, lipid profile and fasting blood glucose levels were collected for all the patients. Body Mass Index (BMI) was calculated. Results A total of 80 patients were recruited, 40 cases and 40 controls. The mean values for all the lipid and glucose parameters were high in cases as compared to controls with significant p-values. Conclusion In the present study metabolic derangements were seen in patients with LP. PMID:28050485

  2. Adult Health: Worried About Empty Nest Syndrome?

    Science.gov (United States)

    ... clinical diagnosis. Instead, empty nest syndrome is a phenomenon in which parents experience feelings of sadness and loss when the last child leaves home. Although you might actively encourage your ...

  3. Duck-nesting Studies: Lower Souris Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — In this report an attempt has been made to summarize some of the notes made during the nesting studies at the Lower Souris Refuge in 1937. While assisting Mr....

  4. Chesapeake Bay Bald Eagle Nesting Survey

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Chesapeake Bay population of breeding bald eagles increased dramatically in 1981 in not only the number of breeding pairs but in the number of nests hatching...

  5. Island's terns nest again after unsuccessful start

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — For five consecutive summers the Trustees of Reservations have directed a program on Nantucket for the protection of the terns which nest in several colonies around...

  6. Annual survival of Florida nesting loggerheads

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — 30 PAT tags were deployed on nesting loggerhead turtles at Juno Beach, FL in June 2012. There have been three premature pop-offs, one of which appeared to be a...

  7. Alcid Nesting Habitat on the Maine Coast

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Maine supports an extensive seabird population because of the abundance of relatively inaccessible rocky coastal islands which are ideal nesting grounds for many...

  8. Nesting Loggerhead Sea Turtle Activity Report 2001

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This paper presents results from the 9th Annual Study (using Army Corp of Engineers funds) of nesting by the Atlantic loggerhead sea turtle (Caretta caretta) along...

  9. Nesting Loggerhead Sea Turtle Activity Report 1998

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This paper presents results from the sixth annual study of nesting along the Atlantic Oceanfront by the loggerhead sea turtle (Caretta carettd) in Virginia Beach,...

  10. Nesting Loggerhead Sea Turtle Activity Report 1999

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This paper presents results from the seventh annual study (using Army Corp of Engineers funds;) of nesting along the Atlantic Ocean coastline by the loggerhead sea...

  11. Starling nest box monitoring [Rocky Mountain Arsenal

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document described the standard operating procedures for observing and recording data collected from starling nest box monitoring at the Rocky Mountain Arsenal....

  12. Cackling Canada goose nesting populations, Yukon Delta

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Number of potential territories, number of cackling Canada Goose nests, and percent occupancy of available territories from CCG plots on the Yukon Delta National...

  13. Simple Algorithms to Calculate Asymptotic Null Distributions of Robust Tests in Case-Control Genetic Association Studies in R

    Directory of Open Access Journals (Sweden)

    Wing Kam Fung

    2010-02-01

    Full Text Available The case-control study is an important design for testing association between genetic markers and a disease. The Cochran-Armitage trend test (CATT is one of the most commonly used statistics for the analysis of case-control genetic association studies. The asymptotically optimal CATT can be used when the underlying genetic model (mode of inheritance is known. However, for most complex diseases, the underlying genetic models are unknown. Thus, tests robust to genetic model misspecification are preferable to the model-dependant CATT. Two robust tests, MAX3 and the genetic model selection (GMS, were recently proposed. Their asymptotic null distributions are often obtained by Monte-Carlo simulations, because they either have not been fully studied or involve multiple integrations. In this article, we study how components of each robust statistic are correlated, and find a linear dependence among the components. Using this new finding, we propose simple algorithms to calculate asymptotic null distributions for MAX3 and GMS, which greatly reduce the computing intensity. Furthermore, we have developed the R package Rassoc implementing the proposed algorithms to calculate the empirical and asymptotic p values for MAX3 and GMS as well as other commonly used tests in case-control association studies. For illustration, Rassoc is applied to the analysis of case-control data of 17 most significant SNPs reported in four genome-wide association studies.

  14. Linear Maps Preserving Idempotence on Nest Algebras

    Institute of Scientific and Technical Information of China (English)

    Jian Lian CUI; Jin Chuan HOU

    2004-01-01

    In this paper, we discuss the rank-1-preserving linear maps on nest algebras of Hilbertspace operators. We obtain several characterizations of such linear maps and apply them to show that a weakly continuous linear bijection on an atomic nest algebra is idempotent preserving if and only if it is a Jordan homomorphism, and in turn, if and only if it is an automorphism or an anti-automorphism.

  15. Body Mass Index, Smoking and Hypertensive Disorders during Pregnancy: A Population Based Case-Control Study.

    Directory of Open Access Journals (Sweden)

    Thuridur A Gudnadóttir

    Full Text Available While obesity is an indicated risk factor for hypertensive disorders of pregnancy, smoking during pregnancy has been shown to be inversely associated with the development of preeclampsia and gestational hypertension. The purpose of this study was to investigate the combined effects of high body mass index and smoking on hypertensive disorders during pregnancy. This was a case-control study based on national registers, nested within all pregnancies in Iceland 1989-2004, resulting in birth at the Landspitali University Hospital. Cases (n = 500 were matched 1:2 with women without a hypertensive diagnosis who gave birth in the same year. Body mass index (kg/m2 was based on height and weight at 10-15 weeks of pregnancy. We used logistic regression models to calculate odds ratios and corresponding 95% confidence intervals as measures of association, adjusting for potential confounders and tested for additive and multiplicative interactions of body mass index and smoking. Women's body mass index during early pregnancy was positively associated with each hypertensive outcome. Compared with normal weight women, the multivariable adjusted odds ratio for any hypertensive disorder was 1.8 (95% confidence interval, 1.3-2.3 for overweight women and 3.1 (95% confidence interval, 2.2-4.3 for obese women. The odds ratio for any hypertensive disorder with obesity was 3.9 (95% confidence interval 1.8-8.6 among smokers and 3.0 (95% confidence interval 2.1-4.3 among non-smokers. The effect estimates for hypertensive disorders with high body mass index appeared more pronounced among smokers than non-smokers, although the observed difference was not statistically significant. Our findings may help elucidate the complicated interplay of these lifestyle-related factors with the hypertensive disorders during pregnancy.

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

    Science.gov (United States)

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

    2016-10-01

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

  17. Association between smoking habits and acne vulgaris. A case-control study

    Directory of Open Access Journals (Sweden)

    Alice Mannocci

    2012-09-01

    Full Text Available

    Background: acne vulgaris, is one of the most common skin disorder. Previous studies about the role of smoke in the pathogenesis of acne reported contradictory results. The aim of this study was to conduct a case-control study investigating the relationship between tobacco smoking and acne.

    Methods: a case-control study was performed during the period September 2009 - February 2010. A questionnaire was administrated to each participant, to assess the association acne - smoke. Cases were outpatients of the Dermatologic Ambulatory of the “Fiorini” Hospital, Sapienza University of Rome (Italy. Controls were age and gender-matched to the cases. The ratio cases-controls was 1:2. A univariate and a multiple logistic regression analysis were conducted; Odds Ratio (OR and the relative 95% confidence interval (95%CI were assessed. The statistical significance was set at p < 0.05.

    Results: crude OR for the association acne - smoke was 7.26 (IC=2.27-23.18; adjusted OR for sex and age was 5.47 (IC=1.67-17.97. Of 93 cases, 6 had a severe grade of acne (6.5%, 19 had an intermediate grade of acne (20.4%, and 68 had a mild grade of acne (73.1%. No one of the smokers had a severe grade of acne, one had an intermediate grade of acne and 11 had mild acne; these differences are not statistically significant.

    Conclusions: the association between acne and smoke shows an increased risk (OR=7.26 with a statistically significant CI. Moreover, people ≥ 18 years of age have twice the risk compared to persons < 18 years of age (OR=2.31.

  18. Gregarious nesting - An anti-predator response in laying hens

    DEFF Research Database (Denmark)

    Riber, Anja Brinch

    2012-01-01

    Gregarious nesting can be defined as a behaviour that occurs when a laying hen (Gallus gallus domesticus) given the choice between an occupied and an unoccupied nest site chooses the occupied nest site. It occurs frequently in flocks of laying hens kept under commercial conditions, contrasting...... the behaviour displayed by feral hens that isolate themselves from the flock during nesting activities. What motivates laying hens to perform gregarious nesting is unknown. One possibility is that gregarious nesting is an anti-predator response to the risk of nest predation emerging from behavioural flexibility...... in nesting strategy. The aim of the present experiment was to investigate whether gregarious nesting due to behavioural flexibility in nesting strategy is an anti-predator response. Twelve groups of 14–15 Isa Warren hens age 44 weeks were housed in pens each containing three adjacent roll-out nest boxes...

  19. Malaria diagnosis from pooled blood samples: comparative analysis of real-time PCR, nested PCR and immunoassay as a platform for the molecular and serological diagnosis of malaria on a large-scale

    Directory of Open Access Journals (Sweden)

    Giselle FMC Lima

    2011-09-01

    Full Text Available Malaria diagnoses has traditionally been made using thick blood smears, but more sensitive and faster techniques are required to process large numbers of samples in clinical and epidemiological studies and in blood donor screening. Here, we evaluated molecular and serological tools to build a screening platform for pooled samples aimed at reducing both the time and the cost of these diagnoses. Positive and negative samples were analysed in individual and pooled experiments using real-time polymerase chain reaction (PCR, nested PCR and an immunochromatographic test. For the individual tests, 46/49 samples were positive by real-time PCR, 46/49 were positive by nested PCR and 32/46 were positive by immunochromatographic test. For the assays performed using pooled samples, 13/15 samples were positive by real-time PCR and nested PCR and 11/15 were positive by immunochromatographic test. These molecular methods demonstrated sensitivity and specificity for both the individual and pooled samples. Due to the advantages of the real-time PCR, such as the fast processing and the closed system, this method should be indicated as the first choice for use in large-scale diagnosis and the nested PCR should be used for species differentiation. However, additional field isolates should be tested to confirm the results achieved using cultured parasites and the serological test should only be adopted as a complementary method for malaria diagnosis.

  20. A model of the best-of-N nest-site selection process in honeybees

    CERN Document Server

    Reina, Andreagiovanni; Trianni, Vito; Bose, Thomas

    2016-01-01

    The ability of a honeybee swarm to select the best nest site plays a fundamental role in determining the future colony's fitness. To date, the nest-site selection process has mostly been modelled and theoretically analysed for the case of binary decisions. However, when the number of alternative nests is larger than two, the decision process dynamics qualitatively change. In this work, we extend previous analyses of a value-sensitive decision-making mechanism to a decision process among N nests. First, we present the decision-making dynamics in the symmetric case of N equal-quality nests. Then, we generalise our findings to a best-of-N decision scenario with one superior nest and N-1 inferior nests, previously studied empirically in bees and ants. Whereas previous binary models highlighted the crucial role of inhibitory stop-signalling, the key parameter in our new analysis is the relative time invested by swarm members in individual discovery and in signalling behaviours. Our new analysis reveals conflicting...

  1. The mathematics of non-linear metrics for nested networks

    Science.gov (United States)

    Wu, Rui-Jie; Shi, Gui-Yuan; Zhang, Yi-Cheng; Mariani, Manuel Sebastian

    2016-10-01

    Numerical analysis of data from international trade and ecological networks has shown that the non-linear fitness-complexity metric is the best candidate to rank nodes by importance in bipartite networks that exhibit a nested structure. Despite its relevance for real networks, the mathematical properties of the metric and its variants remain largely unexplored. Here, we perform an analytic and numeric study of the fitness-complexity metric and a new variant, called minimal extremal metric. We rigorously derive exact expressions for node scores for perfectly nested networks and show that these expressions explain the non-trivial convergence properties of the metrics. A comparison between the fitness-complexity metric and the minimal extremal metric on real data reveals that the latter can produce improved rankings if the input data are reliable.

  2. Nesting Activity of Loggerhead Turtles (Caretta caretta at Göksu Delta, Turkey during 2004 and 2008 nesting seasons

    Directory of Open Access Journals (Sweden)

    Salih H. Durmus

    2011-07-01

    Full Text Available Göksu Delta is one of the most important nesting beaches in Turkey for the endangered loggerhead turtle (Caretta caretta. This paper provides information on the nesting activities of loggerhead turtles, the spatial and temporal distribution of nesting, nesting success, nesting density, hatching success, incubation duration and clutch size over two nesting seasons. A total of 902 emergences occurred over two seasons, of which 239 (26.5% nests were deposited (137 nests in 2004 and 102 nests in 2008 and the overall mean nesting density was 3.4 nests/km. The peak of nesting emergences takes place mainly in June. Of the overall nests, 226 (94.6% were excavated and 16044 eggs were counted. Of these eggs, 3680 (22.9% hatchlings emerged and 2695 (73.2% of hatchlings of them were able to reach the sea. The mean number of eggs per clutch was 71 (range: 15 – 143. The shortest and longest incubation duration in these 2 seasons ranged from 46 to 62 days with a mean of 53 days. The main problems are negatively affecting loggerhead turtle population at Göksu Delta are dense jackal predation both adult and eggs and inundation in nests. The average nesting effort here (mean: 119.5 nests/season confirms that Göksu Delta is one of the most important nesting sites for loggerhead turtles in Turkey.

  3. Nonparametric Bayes modeling for case control studies with many predictors.

    Science.gov (United States)

    Zhou, Jing; Herring, Amy H; Bhattacharya, Anirban; Olshan, Andrew F; Dunson, David B

    2016-03-01

    It is common in biomedical research to run case-control studies involving high-dimensional predictors, with the main goal being detection of the sparse subset of predictors having a significant association with disease. Usual analyses rely on independent screening, considering each predictor one at a time, or in some cases on logistic regression assuming no interactions. We propose a fundamentally different approach based on a nonparametric Bayesian low rank tensor factorization model for the retrospective likelihood. Our model allows a very flexible structure in characterizing the distribution of multivariate variables as unknown and without any linear assumptions as in logistic regression. Predictors are excluded only if they have no impact on disease risk, either directly or through interactions with other predictors. Hence, we obtain an omnibus approach for screening for important predictors. Computation relies on an efficient Gibbs sampler. The methods are shown to have high power and low false discovery rates in simulation studies, and we consider an application to an epidemiology study of birth defects.

  4. Case-Control Study of Parturient Hemoglobinuria in Buffaloes

    Directory of Open Access Journals (Sweden)

    Altaf Mahmood*, Muhammad Athar Khan, Muhammad Younus1, Muhammad Arif Khan2, Hafiz Javed Iqbal3 and Abdul Ahad4

    2012-06-01

    Full Text Available Population based case control study of parturient hemoglobinuria was conducted in District Chakwal during April 2009 to January 2011 for quantification of epidemiological risk factors associated with condition. Data of 180 case–control pairs were analyzed for various hypothesized risk factors. Odds ratios calculated for ≥7 years age (5.56, ≥7 months pregnancy (15.80, ≥3 lactation number (6.39, ≥8 liters daily milk yield (1.07, ≤60 days postpartum period (6.23, previous history of hemoglobinuria (3.41 and ingestion of cruciferous plants (2.51 were significant (P˂0.05; whereas, those recorded for cottonseed cake (1, use of mineral mixture (0.81, use of drugs (1.07, use of oxytocin injection (1.32, vaccination (1, grazing (0.91 and previous history of diseases other than parturient hemoglobinuria (1.19 were insignificant (P>0.05. It was concluded that parturient hemoglobinuria is strongly associated with age, lactation number, stage of pregnancy, postpartum period and previous disease history of affected animals.

  5. Potential risk factors for diabetic neuropathy: a case control study

    Directory of Open Access Journals (Sweden)

    Nooraei Mahdi

    2005-12-01

    Full Text Available Abstract Background Diabetes mellitus type II afflicts at least 2 million people in Iran. Neuropathy is one of the most common complications of diabetes and lowers the patient's quality of life. Since neuropathy often leads to ulceration and amputation, we have tried to elucidate the factors that can affect its progression. Methods In this case-control study, 110 diabetic patients were selected from the Shariati Hospital diabetes clinic. Michigan Neuropathic Diabetic Scoring (MNDS was used to differentiate cases from controls. The diagnosis of neuropathy was confirmed by nerve conduction studies (nerve conduction velocity and electromyography. The multiple factors compared between the two groups included consumption of angiotensin converting enzyme inhibitors (ACEI, blood pressure, serum lipid level, sex, smoking, method of diabetes control and its quality. Results Statistically significant relationships were found between neuropathy and age, gender, quality of diabetes control and duration of disease (P values in the order: 0.04, 0.04, Conclusion In this study, hyperglycemia was the only modifiable risk factor for diabetic neuropathy. Glycemic control reduces the incidence of neuropathy, slows its progression and improves the diabetic patient's quality of life. More attention must be paid to elderly male diabetic patients with poor diabetes control with regard to regular foot examinations and more practical education.

  6. A case-control study of visual acuity in onychocryptosis.

    LENUS (Irish Health Repository)

    Hogan, Aisling M

    2012-02-01

    BACKGROUND: There are many theories surrounding the etiology of ingrown toenails (IGTN). Few factors have been formally assessed, but it is widely accepted that a poor nail cutting technique has a causative role. AIM: To investigate the hypothesis that decreased visual acuity may lead to inadequate nail cutting and the formation of IGTN. METHODS: A prospective case-control study was performed. Near and distance visual acuity were tested on a population with IGTN (n = 19) and compared with that of an age- and sex-matched control cohort (n = 24) who underwent epidermal cyst excision in the same tertiary referral center. Comparisons of visual acuity were made between groups by Mann-Whitney U-test. Differences were taken to be significant if P < 0.05. Institutional Review Board approval was sought and granted. RESULTS: No significant difference in visual acuity (near or distance) was demonstrated between patients with IGTN and the control group (P = 0.33). CONCLUSION: Visual acuity does not appear to play a significant role in the development of IGTN.

  7. Ovarian endometriomas and IVF: a retrospective case-control study

    Directory of Open Access Journals (Sweden)

    Guidetti Daniela

    2011-06-01

    Full Text Available Abstract We performed this retrospective case-control study analyzing 428 first-attempt in vitro fertilization (IVF cycles, among which 254 involved women with a previous or present diagnosis of ovarian endometriosis. First, the results of these 254 cycles were compared with 174 cycles involving patients with proven non-endometriotic tubal infertility having similar age and body mass index. Women with ovarian endometriosis had a significantly higher cancellation rate, but similar pregnancy, implantation and delivery rates as patients with tubal infertility. Second, among the women with ovarian endometriosis, the women with a history of laparoscopic surgery for ovarian endometriomas prior to IVF and no visual endometriosis at ovum pick-up (n = 112 were compared with the non-operated women and visual endometriomas at ovum pick-up (n = 142. Patients who underwent ovarian surgery before IVF had significantly shorter period, lower antral follicle count and required higher gonadotropin doses than patients with non-operated endometriomas. The two groups of women with a previous or present ovarian endometriosis did, however, have similar pregnancy, implantation and live birth rates. In conclusion, ovarian endometriosis does not reduce IVF outcome compared with tubal factor. Furthermore, laparoscopic removal of endometriomas does not improve IVF results, but may cause a decrease of ovarian responsiveness to gonadotropins.

  8. A CASE-CONTROL EPIDEMIOLOGIC STUDY OF ENDOMETRIOSIS

    Institute of Scientific and Technical Information of China (English)

    韩美玲; 潘凌亚; 吴葆桢; 边旭明

    1994-01-01

    A case-control study involving 203 cases of pelvic endometriosis seen from 1987-1989,and 406 randomly selected and age-matched community controls was conducted in order to provide information relevant to effective prophylxaix of the disease.The diagnosis was confirmed by pathology from laparotomy and/or laproscopy.A questionnaire focused on menstrual,marital and reproductive status,professional exposurs and physical activities,and the results were analyzed by a conditional logistic regression model.Women characterized by earlier menarche (≤12 years)and longer period(≥8 days)were found to be saaociated with an elevated incurring risk,and a trend of increasing risk associated with primary dysmenorrhea(RR=2.1 for mild to moderate and RR=5.2 for severe dysmenorrhea),energetic physical activity during menstruation(RR=2.1),and allergic diathesis (RR=1.8)was seen.An inverse relationship was observed between the number of pregnancies and risk of endometrio-sis,and the protective effect was most significant when only the number of full-term pregnancies was counted.The risk factors of endometriosis are discussed,and intensive treatment of primary dysmenorrhea and avoidance of strenuous exercise during menstruation are identified as important as important measures in the prevention of endometriosis.

  9. Baldness and testicular cancer: the EPSAM case-control study.

    Science.gov (United States)

    Moirano, G; Zugna, D; Grasso, C; Lista, P; Ciuffreda, L; Segnan, N; Merletti, F; Richiardi, L

    2016-03-01

    The etiology of testicular cancer is largely unexplained. Research has mainly focused on prenatal exposures, especially to sex hormones, while less attention has been paid to exposures that may act also postnatally. As baldness has been previously associated with testicular cancer risk we focused on baldness and body hairiness, which are both associated with androgen activity. We used data of the Postnatal Exposures and Male Health (EPSAM) study, a case-control study on testicular cancer conducted in the Province of Turin, Italy, involving cases diagnosed between 1997 and 2008. Information was collected using mailed questionnaires. Analyses included 255 cases and 459 controls. We calculated ORs and 95% CIs to estimate testicular cancer risk among those who developed baldness and among those with body hairiness. We found an inverse association between testicular cancer and baldness (OR: 0.67, 95% CI: 0.46-0.98) and body hairiness (OR: 0.78, 95% CI: 0.53-1.16), although the latter had wider CIs. The inverse association between baldness and testicular cancer is consistent with the results from previous studies. These results suggest that androgens activity may influence testicular cancer risk.

  10. Shrinkage Estimators for Robust and Efficient Inference in Haplotype-Based Case-Control Studies

    KAUST Repository

    Chen, Yi-Hau

    2009-03-01

    Case-control association studies often aim to investigate the role of genes and gene-environment interactions in terms of the underlying haplotypes (i.e., the combinations of alleles at multiple genetic loci along chromosomal regions). The goal of this article is to develop robust but efficient approaches to the estimation of disease odds-ratio parameters associated with haplotypes and haplotype-environment interactions. We consider "shrinkage" estimation techniques that can adaptively relax the model assumptions of Hardy-Weinberg-Equilibrium and gene-environment independence required by recently proposed efficient "retrospective" methods. Our proposal involves first development of a novel retrospective approach to the analysis of case-control data, one that is robust to the nature of the gene-environment distribution in the underlying population. Next, it involves shrinkage of the robust retrospective estimator toward a more precise, but model-dependent, retrospective estimator using novel empirical Bayes and penalized regression techniques. Methods for variance estimation are proposed based on asymptotic theories. Simulations and two data examples illustrate both the robustness and efficiency of the proposed methods.

  11. The effects of large beach debris on nesting sea turtles

    Science.gov (United States)

    Fujisaki, Ikuko; Lamont, Margaret M.

    2016-01-01

    A field experiment was conducted to understand the effects of large beach debris on sea turtle nesting behavior as well as the effectiveness of large debris removal for habitat restoration. Large natural and anthropogenic debris were removed from one of three sections of a sea turtle nesting beach and distributions of nests and false crawls (non-nesting crawls) in pre- (2011–2012) and post- (2013–2014) removal years in the three sections were compared. The number of nests increased 200% and the number of false crawls increased 55% in the experimental section, whereas a corresponding increase in number of nests and false crawls was not observed in the other two sections where debris removal was not conducted. The proportion of nest and false crawl abundance in all three beach sections was significantly different between pre- and post-removal years. The nesting success, the percent of successful nests in total nesting attempts (number of nests + false crawls), also increased from 24% to 38%; however the magnitude of the increase was comparably small because both the number of nests and false cr