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Sample records for genetic epidemiological study

  1. GESDB: a platform of simulation resources for genetic epidemiology studies.

    PubMed

    Yao, Po-Ju; Chung, Ren-Hua

    2016-01-01

    Computer simulations are routinely conducted to evaluate new statistical methods, to compare the properties among different methods, and to mimic the observed data in genetic epidemiology studies. Conducting simulation studies can become a complicated task as several challenges can occur, such as the selection of an appropriate simulation tool and the specification of parameters in the simulation model. Although abundant simulated data have been generated for human genetic research, currently there is no public database designed specifically as a repository for these simulated data. With the lack of such a database, for similar studies, similar simulations may have been repeated, which resulted in redundant work. Thus, we created an online platform, the Genetic Epidemiology Simulation Database (GESDB), for simulation data sharing and discussion of simulation techniques for genetic epidemiology studies. GESDB consists of a database for storing simulation scripts, simulated data and documentation from published articles as well as a discussion forum, which provides a platform for discussion of the simulated data and exchanging simulation ideas. Moreover, summary statistics such as the simulation tools that are most commonly used and datasets that are most frequently downloaded are provided. The statistics will be informative for researchers to choose an appropriate simulation tool or select a common dataset for method comparisons. GESDB can be accessed at http://gesdb.nhri.org.twDatabase URL: http://gesdb.nhri.org.tw. PMID:27242038

  2. GESDB: a platform of simulation resources for genetic epidemiology studies.

    PubMed

    Yao, Po-Ju; Chung, Ren-Hua

    2016-01-01

    Computer simulations are routinely conducted to evaluate new statistical methods, to compare the properties among different methods, and to mimic the observed data in genetic epidemiology studies. Conducting simulation studies can become a complicated task as several challenges can occur, such as the selection of an appropriate simulation tool and the specification of parameters in the simulation model. Although abundant simulated data have been generated for human genetic research, currently there is no public database designed specifically as a repository for these simulated data. With the lack of such a database, for similar studies, similar simulations may have been repeated, which resulted in redundant work. Thus, we created an online platform, the Genetic Epidemiology Simulation Database (GESDB), for simulation data sharing and discussion of simulation techniques for genetic epidemiology studies. GESDB consists of a database for storing simulation scripts, simulated data and documentation from published articles as well as a discussion forum, which provides a platform for discussion of the simulated data and exchanging simulation ideas. Moreover, summary statistics such as the simulation tools that are most commonly used and datasets that are most frequently downloaded are provided. The statistics will be informative for researchers to choose an appropriate simulation tool or select a common dataset for method comparisons. GESDB can be accessed at http://gesdb.nhri.org.twDatabase URL: http://gesdb.nhri.org.tw.

  3. GESDB: a platform of simulation resources for genetic epidemiology studies

    PubMed Central

    Yao, Po-Ju; Chung, Ren-Hua

    2016-01-01

    Computer simulations are routinely conducted to evaluate new statistical methods, to compare the properties among different methods, and to mimic the observed data in genetic epidemiology studies. Conducting simulation studies can become a complicated task as several challenges can occur, such as the selection of an appropriate simulation tool and the specification of parameters in the simulation model. Although abundant simulated data have been generated for human genetic research, currently there is no public database designed specifically as a repository for these simulated data. With the lack of such a database, for similar studies, similar simulations may have been repeated, which resulted in redundant work. Thus, we created an online platform, the Genetic Epidemiology Simulation Database (GESDB), for simulation data sharing and discussion of simulation techniques for genetic epidemiology studies. GESDB consists of a database for storing simulation scripts, simulated data and documentation from published articles as well as a discussion forum, which provides a platform for discussion of the simulated data and exchanging simulation ideas. Moreover, summary statistics such as the simulation tools that are most commonly used and datasets that are most frequently downloaded are provided. The statistics will be informative for researchers to choose an appropriate simulation tool or select a common dataset for method comparisons. GESDB can be accessed at http://gesdb.nhri.org.tw. Database URL: http://gesdb.nhri.org.tw PMID:27242038

  4. Recruiting American Indian Women for a Genetic Epidemiology Study

    PubMed Central

    Nadeau, M.; Best, L.

    2010-01-01

    Due to previous negative experiences, some American Indian communities are distrustful of research in general and genetic research in particular. The Turtle Mountain Community College was awarded a National Institutes of Health (NIH) grant with 3 aims: (1) to study possible genetic influences on pre-eclampsia, (2) to encourage tribal college students to consider biomedical careers and (3) to develop the local research infrastructure. Retrospectively identified case (91) and control (188) participants were recruited into Phase I over a 3-year period and additional participants (71) were concurrently recruited from a prenatal clinic into a prospective case/control study, Phase II. This paper describes some of the challenges and solutions we encountered in the process of recruiting American Indian participants into a genetic epidemiologic study. PMID:20616521

  5. [Molecular and genetic epidemiology].

    PubMed

    Kang, D H

    2001-04-21

    Molecular epidemiology is defined as "the use of biological markers in epidemiologic research" and genetic epidemiology is defined as "the study of the interaction between genetic and environmental factors in epidemiologic research". Traditional epidemiologic approaches defined as "the study of the distribution and determinants of disease frequency in human population" could not address the importance of genetic susceptibility of humans in disease occurrence. However, the use of biological or genetic markers identified and characterized by the help of advance in molecular biology and human genetics now can provide us better understanding of multi-factorial or multistep disease occurrence in humans. Biological markers used in molecular epidemiology are classified into three groups: biomarkers of exposure (i.e., carcinogen metabolites in human urine, DNA-adducts, etc.), biomarkers of effects (i.e., oncoproteins, tumor markers, etc.), and biomarkers of susceptibility (i.e., genetic polymorphisms of carcinogen metabolism enzymes, DNA repair, etc.). Susceptibility genes involved in disease pathogenesis are categorized into two groups: high penetrance genes (i.e., BRAC1, RB, etc.) and low penetrance genes (i.e., GSTs, XRCC1, etc.). This paper will address the usefulnesses of bomarkers in edpidemiologic research and will show the examples of the use of selected low penetrance genes involved in human carcinogenesis. The importance of multidisciplinary approaches among epidemiologists, molecular biologists, and human geneticists will also be discussed.

  6. Study design in genetic epidemiology: theoretical and practical considerations.

    PubMed

    Whittemore, A S; Nelson, L M

    1999-01-01

    Recent advances in molecular genetics have created new opportunities and challenges for genetic epidemiologists. Here we review some of the issues that arise when designing a study involving the genetic epidemiology of chronic diseases of late onset, such as cancer. We discuss two considerations that influence the choice of design. The first consideration is the study's goals. We describe the goals of identifying new susceptibility genes for a disease, of estimating important characteristics of known genes, and of learning how to prevent the disease in the genetically susceptible. We indicate how these goals affect the choice of design and present some guidelines for choosing designs that effectively address them. The second consideration is the set of practical constraints to successfully conducting the research. These contraints include problems of potential selection bias, reduced response rates, problems particular to family registries, problems particular to the cultures of various ethnic groups, and ethical issues. We indicate how these constraints affect the choice of design and discuss ways to deal with them. PMID:10854488

  7. An epidemiological and genetic study of facial clefting in France. I. Epidemiology and frequency in relatives.

    PubMed Central

    Bonaiti, C; Briard, M L; Feingold, J; Pavy, B; Psaume, J; Migne-Tufferaud, G; Kaplan, J

    1982-01-01

    The frequencies of cleft lip with or without cleft palate (CL(P)) and isolated cleft palate (CP) have been estimated in France to be 0.082% and 0.035%, respectively, after exclusion of malformation syndromes. A genetic and epidemiological study has been carried out on 468 patients with CL(P) and 163 with CP. The results are given in detail and some specific points are discussed: the apparently low incidence in France, the relationship between sex ratio and abortion rates, the maternal effects, and the possibility of an association between CL(P) and CP. PMID:7200146

  8. Genetic analysis of metabolic polymorphisms in molecular epidemiological studies: social and ethical implications.

    PubMed

    Hainaut, P; Vähäkangas, K

    1999-01-01

    The use of genetic biomarkers in epidemiological studies raises specific social and ethical issues related to the selection of molecular markers and methods of analysis, obtaining participation, the storage of biological samples and their linkage with individual data, the disclosure of information and the publication of results. Several of these issues are similar to those associated with the use of any type of biomarker in epidemiology. Other problems are specifically related to the use of genetic material and the perception that genetic information raises special concerns regarding privacy, risk of abuse and psychosocial impact in this chapter we define how genetic studies performed in the context of molecular epidemiological studies (genetic analysis) differ from genetic screening or genetic testing conducted in a clinical or public health context We then examine the ethical implications of this distinction and describe how general ethical principles may apply to genetic analysis in the area of molecular epidemiology. In particular we discuss specific questions such as those of obtaining participation, working with archival samples and communicating results. We advocate an approach whereby ethical issues are tackled as an intrinsic part of study design; this requires broad discussion with all the parties involved.

  9. Ecogeographic Genetic Epidemiology

    PubMed Central

    Sloan, Chantel D.; Duell, Eric J.; Shi, Xun; Irwin, Rebecca; Andrew, Angeline S.; Williams, Scott M.; Moore, Jason H.

    2009-01-01

    Complex diseases such as cancer and heart disease result from interactions between an individual's genetics and environment, i.e. their human ecology. Rates of complex diseases have consistently demonstrated geographic patterns of incidence, or spatial “clusters” of increased incidence relative to the general population. Likewise, genetic subpopulations and environmental influences are not evenly distributed across space. Merging appropriate methods from genetic epidemiology, ecology and geography will provide a more complete understanding of the spatial interactions between genetics and environment that result in spatial patterning of disease rates. Geographic Information Systems (GIS), which are tools designed specifically for dealing with geographic data and performing spatial analyses to determine their relationship, are key to this kind of data integration. Here the authors introduce a new interdisciplinary paradigm, ecogeographic genetic epidemiology, which uses GIS and spatial statistical analyses to layer genetic subpopulation and environmental data with disease rates and thereby discern the complex gene-environment interactions which result in spatial patterns of incidence. PMID:19025788

  10. Genetics of schizophrenia and smoking: an approach to studying their comorbidity based on epidemiological findings

    PubMed Central

    de Leon, Jose; Diaz, Francisco J.

    2012-01-01

    The association between schizophrenia and tobacco smoking has been described in more than 1,000 articles, many with inadequate methodology. The studies on this association can focus on: (1) current smoking, ever smoking or smoking cessation; (2) non-psychiatric controls or controls with severe mental illness (e.g., bipolar disorder); and (3) higher smoking frequency or greater usage in smokers. The association with the most potential for genetic studies is that between ever daily smoking and schizophrenia; it may reflect a shared genetic vulnerability. To reduce the number of false-positive genes, we propose a three-stage approach derived from epidemiological knowledge. In the first stage, only genetic variations associated with ever daily smoking that are simultaneously significant within the non-psychiatric controls, the bipolar disorder controls and the schizophrenia cases will be selected. Only those genetic variations that are simultaneously significant in the three hypothesis tests will be tested in the second stage, where the prevalence of the genes must be significantly higher in schizophrenia than in bipolar disorder, and significantly higher in bipolar disorder than in controls. The genes simultaneously significant in the second stage will be included in a third stage where the gene variations must be significantly more frequent in schizophrenia patients who did not start smoking daily until their 20s (late start) versus those who had an early start. Any genetic approach to psychiatric disorders may fail if attention is not given to comorbidity and epidemiological studies that suggest which comorbidities are likely to be explained by genetics and which are not. Our approach, which examines the results of epidemiological studies on comorbidities and then looks for genes that simultaneously satisfy epidemiologically suggested sets of hypotheses, may also apply to the study of other major illnesses. PMID:22190153

  11. Genetics and epidemiology, congenital anomalies and cancer

    SciTech Connect

    Friedman, J.M.

    1997-03-01

    Many of the basic statistical methods used in epidemiology - regression, analysis of variance, and estimation of relative risk, for example - originally were developed for the genetic analysis of biometric data. The familiarity that many geneticists have with this methodology has helped geneticists to understand and accept genetic epidemiology as a scientific discipline. It worth noting, however, that most of the work in genetic epidemiology during the past decade has been devoted to linkage and other family studies, rather than to population-based investigations of the type that characterize much of mainstream epidemiology. 30 refs., 2 tabs.

  12. Epidemiology and Genetics of Hypertension.

    PubMed

    Sarkar, Taposh; Singh, Narinder Pal

    2015-09-01

    The prevalence of hypertension is increasing in India as well as in the world. The average prevalence of hypertension in India is 25-30%. The median prevalence of total hypertension in 2009 was 37.6% in men and 40.1% in women in U.S. Hypertension is a major risk factor for majority of patients with cardiovascular, cerebrovascular and renal morbidity and mortality. Environmental factors as well as genetic factors account for regulation of blood pressure and its control. Understanding of genetic factor may not only help in recognising those at risk but also help in treatment. Discovering hypertension susceptibility genes would help recognizing those at risk for developing the disease before the expression of clinical symptoms. Genetic and epidemiological studies have suggested that essential hypertension is a polygenic and multifactorial disorder that results from genetic and/or environmental factors. In India awareness, treatment and control status of hypertension is low, with only half of the urban and a quarter of the rural hypertensive individuals being aware of its presence. In this review we have discussed epidemiology and genetics of hypertension, both the monogenic and polygenic forms. PMID:27608868

  13. Genetic epidemiology utilizing the adoption method: studies of obesity and of premature death in adults.

    PubMed

    Sørensen, T I

    1991-03-01

    Genetic epidemiology gives no priority to genes or environment in the search of disease causation. However, a major problem in this field is the disentangling of the effects of environment and genes. The study of subjects separated very early in life from their biologic parents and adopted by unrelated parents provide a strong tool for estimation of genetic and familial environmental influences. The degree to which the trait or disease frequency of the adoptees is similar to that seen among the biologic relatives is an indication of the strength of the genetic influence. Similarity to the adoptive relatives suggests influences of the family environment shared between them. Adoption studies of adult obesity show that it is genes, and not the family environment, that is responsible for the familial aggregation of obesity. A study of the mortality of adult adoptees and their biologic and adoptive parents indicates a genetic influence on the risk of premature death from all causes, from natural causes, infections, and cardio- and cerebrovascular conditions, and suggests familial environmental influences on death from the vascular causes and from cancer.

  14. Genetic taste responses to 6-n-propylthiouracil among adults: a screening tool for epidemiological studies.

    PubMed

    Drewnowski, A; Kristal, A; Cohen, J

    2001-06-01

    Genetically mediated taste responsiveness to 6-n-propylthiouracil (PROP) has been linked to reduced acceptance of some bitter foods. In this community-based study male (n = 364) and female (n = 378) adults enrolled in a self-help dietary intervention trial were screened for PROP taster status. Respondents, aged 18--70 years, were mailed filter papers impregnated with PROP or with aspartame solutions. They received instructions to rate taste intensity and hedonic preference using nine point category scales. Women rated PROP as more bitter than did men. Both sweetness and bitterness ratings were lower for older adults. Taste responsiveness to PROP was unrelated to body mass index in women or men. Higher bitterness ratings for PROP were weakly associated with higher sweetness ratings for aspartame, but were unrelated to sweet taste preferences. Successful administration of PROP filter papers by mail suggests new avenues for the screening of taste phenotypes in epidemiological studies.

  15. Genetic Epidemiology in Aging Research

    PubMed Central

    Matteini, Amy

    2009-01-01

    Over the last two decades, aging research has expanded to include not only age-related disease models, and conversely, longevity and disease-free models, but also focuses on biological mechanisms related to the aging process. By viewing aging on multiple research frontiers, we are rapidly expanding knowledge as a whole and mapping connections between biological processes and particular age-related diseases that emerge. This is perhaps most true in the field of genetics, where variation across individuals has improved our understanding of aging mechanisms, etiology of age-related disease, and prediction of therapeutic responses. A close partnership between gerontologists, epidemiologists, and geneticists is needed to take full advantage of emerging genome information and technology and bring about a new age for biological aging research. Here we review current genetic findings for aging across both disease-specific and aging process domains. We then highlight the limitations of most work to date in terms of study design, genomic information, and trait modeling and focus on emerging technology and future directions that can partner genetic epidemiology and aging research fields to best take advantage of the rapid discoveries in each. PMID:19168782

  16. Selection bias in genetic-epidemiological studies of cleft lip and palate

    SciTech Connect

    Christensen, K.; Holm, N.V.; Kock, K. ); Olsen, J. ); Fogh-Anderson, P.

    1992-09-01

    The possible impact of selection bias in genetic and epidemiological studies of cleft lip and palate was studied, using three nationwide ascertainment sources and an autopsy study in a 10% sample of the Danish population. A total of 670 cases were identified. Two national record systems, when used together, were found suitable for ascertaining facial cleft in live births. More than 95% ascertainment was obtained by means of surgical files for cleft lip (with or without cleft palate) without associated malformations/syndromes. However, surgical files could be a poor source for studying isolated cleft palate (CP) (only a 60% and biased ascertainment), and they cannot be used to study the prevalence of associated malformations or syndromes in facial cleft cases. The male:female ratio was 0.88 in surgically treated cases of CP and was 1.5 in nonoperated CP cases, making the overall sex ratio for CP 1.1 (95% confidence limits 0.86-1.4) The sex ratio for CP without associated malformation was 1.1 (95% confidence limits 0.84-1.6). One of the major test criteria in CP multifactorial threshold models (higher CP liability among male CP relatives) must be reconsidered, if other investigations confirm that a CP sex-ratio reversal to male predominance occurs when high ascertainment is achieved. 24 refs., 1 fig., 4 tabs.

  17. [The epidemiology and genetic of gout].

    PubMed

    Bardin, Thomas; Richette, Pascal

    2011-09-01

    Gout affects 1-2% of adults in developed countries, where it is the most common inflammatory arthritis in men. Epidemiological data are consistent with a rise in the prevalence of gout. Diet and genetic predisposition seem to be the main causal factors of primary gout. Gout and hyperuricaemia are associated with hypertension, diabetes mellitus, metabolic syndrome, and renal and cardiovascular diseases. Genetic studies have found that variants of GLUT9 and ABCG2 were associated with urate levels.

  18. Genetic epidemiology of glioma.

    PubMed

    Malmer, B; Iselius, L; Holmberg, E; Collins, A; Henriksson, R; Grönberg, H

    2001-02-01

    The present study performed a segregation analysis of a cohort of first-degree relatives (FDR) of glioma patients. The families with two or more gliomas were also expanded to determine if any more gliomas could be detected, and if any other types of cancers were associated. These glioma-prone families (n = 24/432) were extended to include first-, second- and third-degree relatives (n = 807) and a cohort was assembled, the standardized incidence risk for other types of cancer calculated and the pedigrees investigated for a possible mode of inheritance. A segregation analysis of the 2141 FDR in 297 families, performed using the Pointer software, did not clearly reject a multifactorial model chi(2)(3) = 6.13, P< 0.2. However, when letting all parameters be free, the recessive model provided the best fit. In the extended families, no increased risk of other types of cancer was found. This population-based study proposes that familial glioma occurs in about 5% of all glioma cases and that 1% have a possible autosomal dominant inheritance. This first segregation analysis performed in familial glioma must be cautiously interpreted, but an autosomal recessive gene provided the best fit, which could possibly explain 2% of all glioma cases. PMID:11161412

  19. Genetic epidemiology of glioma.

    PubMed

    Malmer, B; Iselius, L; Holmberg, E; Collins, A; Henriksson, R; Grönberg, H

    2001-02-01

    The present study performed a segregation analysis of a cohort of first-degree relatives (FDR) of glioma patients. The families with two or more gliomas were also expanded to determine if any more gliomas could be detected, and if any other types of cancers were associated. These glioma-prone families (n = 24/432) were extended to include first-, second- and third-degree relatives (n = 807) and a cohort was assembled, the standardized incidence risk for other types of cancer calculated and the pedigrees investigated for a possible mode of inheritance. A segregation analysis of the 2141 FDR in 297 families, performed using the Pointer software, did not clearly reject a multifactorial model chi(2)(3) = 6.13, P< 0.2. However, when letting all parameters be free, the recessive model provided the best fit. In the extended families, no increased risk of other types of cancer was found. This population-based study proposes that familial glioma occurs in about 5% of all glioma cases and that 1% have a possible autosomal dominant inheritance. This first segregation analysis performed in familial glioma must be cautiously interpreted, but an autosomal recessive gene provided the best fit, which could possibly explain 2% of all glioma cases.

  20. Genetic epidemiology, genetic maps and positional cloning.

    PubMed Central

    Morton, Newton E

    2003-01-01

    Genetic epidemiology developed in the middle of the last century, focused on inherited causes of disease but with methods and results applicable to other traits and even forensics. Early success with linkage led to the localization of genes contributing to disease, and ultimately to the Human Genome Project. The discovery of millions of DNA markers has encouraged more efficient positional cloning by linkage disequilibrium (LD), using LD maps and haplotypes in ways that are rapidly evolving. This has led to large international programmes, some promising and others alarming, with laws about DNA patenting and ethical guidelines for responsible research still struggling to be born. PMID:14561327

  1. Applying Evolutionary Genetics to Schistosome Epidemiology

    PubMed Central

    Steinauer, Michelle L.; Blouin, Michael S.; Criscione, Charles D.

    2010-01-01

    We review how molecular markers and evolutionary analysis have been applied to the study of schistosome parasites, important pathogens that infect over 200 million people worldwide. Topics reviewed include phylogenetics and biogeography, hybridization, infection within snails, mating systems, and genetic structure. Some interesting generalizations include that schistosome species hybridize frequently and have switched definitive hosts repeatedly in evolutionary time. We show that molecular markers can be used to infer epidemiologically-relevant processes such as spatial variation in transmission, or to reveal complex patterns of mate choice. Analysis of genetic structure data shows that transmission foci can be structured by watershed boundaries, habitat types, and host species. We also discuss sampling and analytical problems that arise when using larvae to estimate genetic parameters of adult schistosome populations. Finally, we review pitfalls in methodologies such as genotyping very small individuals, statistical methods for identifying clonemates or for identifying sibling groups, and estimating allele frequencies from pooled egg samples. PMID:20176142

  2. A Molecular Epidemiological and Genetic Diversity Study of Tuberculosis in Ibadan, Nnewi and Abuja, Nigeria

    PubMed Central

    Lawson, Lovett; Zhang, Jian; Gomgnimbou, Michel K.; Abdurrahman, Saddiq T.; Le Moullec, Stéphanie; Mohamed, Fatima; Uzoewulu, Gertrude N.; Sogaolu, Olumide M.; Goh, Khye Seng; Emenyonu, Nnamdi; Refrégier, Guislaine; Cuevas, Luis E.; Sola, Christophe

    2012-01-01

    Background Nigeria has the tenth highest burden of tuberculosis (TB) among the 22 TB high-burden countries in the world. This study describes the biodiversity and epidemiology of drug-susceptible and drug-resistant TB in Ibadan, Nnewi and Abuja, using 409 DNAs extracted from culture positive TB isolates. Methodology/Principal Findings DNAs extracted from clinical isolates of Mycobacterium tuberculosis complex were studied by spoligotyping and 24 VNTR typing. The Cameroon clade (CAM) was predominant followed by the M. africanum (West African 1) and T (mainly T2) clades. By using a smooth definition of clusters, 32 likely epi-linked clusters related to the Cameroon genotype family and 15 likely epi-linked clusters related to other “modern” genotypes were detected. Eight clusters concerned M. africanum West African 1. The recent transmission rate of TB was 38%. This large study shows that the recent transmission of TB in Nigeria is high, without major regional differences, with MDR-TB clusters. Improvement in the TB control programme is imperative to address the TB control problem in Nigeria. PMID:22723859

  3. Familial amyloid polyneuropathy (TTR ala 60) in north west Ireland: a clinical, genetic, and epidemiological study.

    PubMed Central

    Reilly, M M; Staunton, H; Harding, A E

    1995-01-01

    A cluster of cases of familial amyloid polyneuropathy has been described in Donegal, north west Ireland. Two patients from this region have been shown to have the ala 60 mutation in the transthyretin gene. Three kindreds with this mutation have also been described in the United States. Genealogical and haplotype studies indicate that all known patients with this mutation are related and are descended from a founder in north west Ireland. There is evidence for reduced penetrance of this disorder. A population based study showed that 1.1% of the population in this area in north west Ireland carry the mutation. This has implications in terms of diagnosis, genetic counselling, and treatment in the future. PMID:7608709

  4. Effects of smoking on the genetic risk of obesity: the population architecture using genomics and epidemiology study

    PubMed Central

    2013-01-01

    Background Although smoking behavior is known to affect body mass index (BMI), the potential for smoking to influence genetic associations with BMI is largely unexplored. Methods As part of the ‘Population Architecture using Genomics and Epidemiology (PAGE)’ Consortium, we investigated interaction between genetic risk factors associated with BMI and smoking for 10 single nucleotide polymorphisms (SNPs) previously identified in genome-wide association studies. We included 6 studies with a total of 56,466 subjects (16,750 African Americans (AA) and 39,716 European Americans (EA)). We assessed effect modification by testing an interaction term for each SNP and smoking (current vs. former/never) in the linear regression and by stratified analyses. Results We did not observe strong evidence for interactions and only observed two interactions with p-values <0.1: for rs6548238/TMEM18, the risk allele (C) was associated with BMI only among AA females who were former/never smokers (β = 0.018, p = 0.002), vs. current smokers (β = 0.001, p = 0.95, pinteraction = 0.10). For rs9939609/FTO, the A allele was more strongly associated with BMI among current smoker EA females (β = 0.017, p = 3.5x10-5), vs. former/never smokers (β = 0.006, p = 0.05, pinteraction = 0.08). Conclusions These analyses provide limited evidence that smoking status may modify genetic effects of previously identified genetic risk factors for BMI. Larger studies are needed to follow up our results. Clinical Trial Registration NCT00000611 PMID:23311614

  5. The role of epigenetics in genetic and environmental epidemiology.

    PubMed

    Ladd-Acosta, Christine; Fallin, M Daniele

    2016-02-01

    Epidemiology is the branch of science that investigates the causes and distribution of disease in populations in order to provide preventative measures and promote human health. The fields of genetic and environmental epidemiology primarily seek to identify genetic and environmental risk factors for disease, respectively. Epigenetics is emerging as an important piece of molecular data to include in these studies because it can provide mechanistic insights into genetic and environmental risk factors for disease, identify potential intervention targets, provide biomarkers of exposure, illuminate gene-environment interactions and help localize disease-relevant genomic regions. Here, we describe the importance of including epigenetics in genetic and environmental epidemiology studies, provide a conceptual framework when considering epigenetic data in population-based studies and touch upon the many challenges that lie ahead.

  6. Cryptic relatedness in epidemiologic collections accessed for genetic association studies: experiences from the Epidemiologic Architecture for Genes Linked to Environment (EAGLE) study and the National Health and Nutrition Examination Surveys (NHANES).

    PubMed

    Malinowski, Jennifer; Goodloe, Robert; Brown-Gentry, Kristin; Crawford, Dana C

    2015-01-01

    Epidemiologic collections have been a major resource for genotype-phenotype studies of complex disease given their large sample size, racial/ethnic diversity, and breadth and depth of phenotypes, traits, and exposures. A major disadvantage of these collections is they often survey households and communities without collecting extensive pedigree data. Failure to account for substantial relatedness can lead to inflated estimates and spurious associations. To examine the extent of cryptic relatedness in an epidemiologic collection, we as the Epidemiologic Architecture for Genes Linked to Environment (EAGLE) study accessed the National Health and Nutrition Examination Surveys (NHANES) linked to DNA samples ("Genetic NHANES") from NHANES III and NHANES 1999-2002. NHANES are population-based cross-sectional surveys conducted by the National Center for Health Statistics at the Centers for Disease Control and Prevention. Genome-wide genetic data is not yet available in NHANES, and current data use agreements prohibit the generation of GWAS-level data in NHANES samples due issues in maintaining confidentiality among other ethical concerns. To date, only hundreds of single nucleotide polymorphisms (SNPs) genotyped in a variety of candidate genes are available for analysis in NHANES. We performed identity-by-descent (IBD) estimates in three self-identified subpopulations of Genetic NHANES (non-Hispanic white, non- Hispanic black, and Mexican American) using PLINK software to identify potential familial relationships from presumed unrelated subjects. We then compared the PLINKidentified relationships to those identified by an alternative method implemented in Kinship-based INference for Genome-wide association studies (KING). Overall, both methods identified familial relationships in NHANES III and NHANES 1999-2002 for all three subpopulations, but little concordance was observed between the two methods due in major part to the limited SNP data available in Genetic NHANES

  7. Cryptic relatedness in epidemiologic collections accessed for genetic association studies: experiences from the Epidemiologic Architecture for Genes Linked to Environment (EAGLE) study and the National Health and Nutrition Examination Surveys (NHANES)

    PubMed Central

    Malinowski, Jennifer; Goodloe, Robert; Brown-Gentry, Kristin; Crawford, Dana C.

    2015-01-01

    Epidemiologic collections have been a major resource for genotype–phenotype studies of complex disease given their large sample size, racial/ethnic diversity, and breadth and depth of phenotypes, traits, and exposures. A major disadvantage of these collections is they often survey households and communities without collecting extensive pedigree data. Failure to account for substantial relatedness can lead to inflated estimates and spurious associations. To examine the extent of cryptic relatedness in an epidemiologic collection, we as the Epidemiologic Architecture for Genes Linked to Environment (EAGLE) study accessed the National Health and Nutrition Examination Surveys (NHANES) linked to DNA samples (“Genetic NHANES”) from NHANES III and NHANES 1999–2002. NHANES are population-based cross-sectional surveys conducted by the National Center for Health Statistics at the Centers for Disease Control and Prevention. Genome-wide genetic data is not yet available in NHANES, and current data use agreements prohibit the generation of GWAS-level data in NHANES samples due issues in maintaining confidentiality among other ethical concerns. To date, only hundreds of single nucleotide polymorphisms (SNPs) genotyped in a variety of candidate genes are available for analysis in NHANES. We performed identity-by-descent (IBD) estimates in three self-identified subpopulations of Genetic NHANES (non-Hispanic white, non- Hispanic black, and Mexican American) using PLINK software to identify potential familial relationships from presumed unrelated subjects. We then compared the PLINKidentified relationships to those identified by an alternative method implemented in Kinship-based INference for Genome-wide association studies (KING). Overall, both methods identified familial relationships in NHANES III and NHANES 1999–2002 for all three subpopulations, but little concordance was observed between the two methods due in major part to the limited SNP data available in Genetic

  8. Cryptic relatedness in epidemiologic collections accessed for genetic association studies: experiences from the Epidemiologic Architecture for Genes Linked to Environment (EAGLE) study and the National Health and Nutrition Examination Surveys (NHANES).

    PubMed

    Malinowski, Jennifer; Goodloe, Robert; Brown-Gentry, Kristin; Crawford, Dana C

    2015-01-01

    Epidemiologic collections have been a major resource for genotype-phenotype studies of complex disease given their large sample size, racial/ethnic diversity, and breadth and depth of phenotypes, traits, and exposures. A major disadvantage of these collections is they often survey households and communities without collecting extensive pedigree data. Failure to account for substantial relatedness can lead to inflated estimates and spurious associations. To examine the extent of cryptic relatedness in an epidemiologic collection, we as the Epidemiologic Architecture for Genes Linked to Environment (EAGLE) study accessed the National Health and Nutrition Examination Surveys (NHANES) linked to DNA samples ("Genetic NHANES") from NHANES III and NHANES 1999-2002. NHANES are population-based cross-sectional surveys conducted by the National Center for Health Statistics at the Centers for Disease Control and Prevention. Genome-wide genetic data is not yet available in NHANES, and current data use agreements prohibit the generation of GWAS-level data in NHANES samples due issues in maintaining confidentiality among other ethical concerns. To date, only hundreds of single nucleotide polymorphisms (SNPs) genotyped in a variety of candidate genes are available for analysis in NHANES. We performed identity-by-descent (IBD) estimates in three self-identified subpopulations of Genetic NHANES (non-Hispanic white, non- Hispanic black, and Mexican American) using PLINK software to identify potential familial relationships from presumed unrelated subjects. We then compared the PLINKidentified relationships to those identified by an alternative method implemented in Kinship-based INference for Genome-wide association studies (KING). Overall, both methods identified familial relationships in NHANES III and NHANES 1999-2002 for all three subpopulations, but little concordance was observed between the two methods due in major part to the limited SNP data available in Genetic NHANES

  9. Review of the Diabetes Heart Study (DHS) family of studies: a comprehensively examined sample for genetic and epidemiological studies of type 2 diabetes and its complications.

    PubMed

    Bowden, Donald W; Cox, Amanda J; Freedman, Barry I; Hugenschimdt, Christina E; Wagenknecht, Lynne E; Herrington, David; Agarwal, Subhashish; Register, Thomas C; Maldjian, Joseph A; Ng, Maggie C-Y; Hsu, Fang-Chi; Langefeld, Carl D; Williamson, Jeff D; Carr, J Jeffrey

    2010-01-01

    The Diabetes Heart Study (DHS) is a genetic and epidemiological study of 1,443 European American and African American participants from 564 families with multiple cases of type 2 diabetes. Initially, participants were comprehensively examined for measures of subclinical cardiovascular disease (CVD) including computed tomography measurement of vascular calcified plaque, ultrasound imaging of carotid artery wall thickness, and electrocardiographic intervals. Subsequent studies have investigated the relationship between bone mineral density and vascular calcification, measures of adiposity, and biomarkers. Ongoing studies are carrying out an extensive evaluation of cerebrovascular disease using magnetic resonance imaging and cognitive assessment. A second, parallel study, the African American DHS, has expanded the sample of African Americans to investigate marked racial differences in subclinical CVD between European Americans and African Americans. Studies in development will evaluate the impact of social stress during the lifecourse on CVD risk, and the prevalence of gastroparesis in this diabetes enriched sample. In addition, the ongoing high mortality rate in DHS participants provides novel insights into the increased risks for type 2 diabetes affected individuals. A comprehensive genetic analysis of the sample is underway using the genome-wide association study (GWAS) approach. Data from this GWAS survey will complement prior family-based linkage data in the analysis of genetic contributors to the wide range of traits in the sample. To our knowledge the DHS family of studies has created the most comprehensively examined sample of individuals with type 2 diabetes yet available, and represents a unique resource for the study people with type 2 diabetes. The aim of this review is to provide a collective overview of the major results from the DHS family of studies, and relate them to the larger body of biomedical investigations of diabetes and its complications. PMID

  10. Overview of Genetic-epidemiological Studies in Ethnically and Demographically Diverse Isolates of Dagestan, Northern Caucasus, Russia

    PubMed Central

    Bulayeva, Kazima B.

    2006-01-01

    Aim To assess genetic diversity and genetic distances among isolated populations from Dagestan. Methods A cross-population genetic epidemiology design was applied in ethnically and demographically diverse isolates from Dagestan, some with more than 200 and some with less than 100 generations of demographical history since their founding. Results The analysis of genetic diversity showed that Dagestan ethnic populations are clearly close to European ethnic populations. The genetic data support the view of them as ancient, highly isolated populations 85%-97% the rate of the endogamy and inbreeding coefficient F = 0.010-0.015. Many Dagestan populations have very high prevalence of certain complex diseases such as cardiovascular illnesses, cancer, schizophrenia, mental retardation, and progressive muscular dystrophy. Lifetime morbid risk for schizophrenia in the isolates varied from 0 to 5%. Among the relatives, the number of men with chronic schizophrenia was at least twice as high as women. The average age of onset of schizophrenia was 21.2 years for offspring of consanguineous marriages and 17.4 years for offspring of non-consanguineous marriages (P = 0.033). Conclusion The results support the hypothesis that cross-population design provides unique opportunities for observing reliable ancestral haplotypes with disease predisposing loci, as well as population-specific linked loci. PMID:16912990

  11. HuGE Watch: tracking trends and patterns of published studies of genetic association and human genome epidemiology in near-real time.

    PubMed

    Yu, Wei; Wulf, Anja; Yesupriya, Ajay; Clyne, Melinda; Khoury, Muin Joseph; Gwinn, Marta

    2008-09-01

    HuGE Watch is a web-based application for tracking the evolution of published studies on genetic association and human genome epidemiology in near-real time. The application allows users to display temporal trends and spatial distributions as line charts and google maps, providing a quick overview of progress in the field. http://www.hugenavigator.net/HuGENavigator/startPageWatch.do

  12. Nosology, epidemiology and genetics of schizophrenia

    SciTech Connect

    Tsuang, M.T.; Simpson, J.C. )

    1988-01-01

    This book contains 25 selections. Some of the titles are: The genetics of schizophrenia: An overview; The genetics of schizo-affective disorder and the schizophrenia spectrum; Mathematical models of genetic transmission; and Genetic studies of biochemical, pathophysiological and pharmacological factors in schizophrenia.

  13. Melanocortin-1 receptor, skin cancer and phenotypic characteristics (M-SKIP) project: study design and methods for pooling results of genetic epidemiological studies

    PubMed Central

    2012-01-01

    Background For complex diseases like cancer, pooled-analysis of individual data represents a powerful tool to investigate the joint contribution of genetic, phenotypic and environmental factors to the development of a disease. Pooled-analysis of epidemiological studies has many advantages over meta-analysis, and preliminary results may be obtained faster and with lower costs than with prospective consortia. Design and methods Based on our experience with the study design of the Melanocortin-1 receptor (MC1R) gene, SKin cancer and Phenotypic characteristics (M-SKIP) project, we describe the most important steps in planning and conducting a pooled-analysis of genetic epidemiological studies. We then present the statistical analysis plan that we are going to apply, giving particular attention to methods of analysis recently proposed to account for between-study heterogeneity and to explore the joint contribution of genetic, phenotypic and environmental factors in the development of a disease. Within the M-SKIP project, data on 10,959 skin cancer cases and 14,785 controls from 31 international investigators were checked for quality and recoded for standardization. We first proposed to fit the aggregated data with random-effects logistic regression models. However, for the M-SKIP project, a two-stage analysis will be preferred to overcome the problem regarding the availability of different study covariates. The joint contribution of MC1R variants and phenotypic characteristics to skin cancer development will be studied via logic regression modeling. Discussion Methodological guidelines to correctly design and conduct pooled-analyses are needed to facilitate application of such methods, thus providing a better summary of the actual findings on specific fields. PMID:22862891

  14. SITVITWEB--a publicly available international multimarker database for studying Mycobacterium tuberculosis genetic diversity and molecular epidemiology.

    PubMed

    Demay, Christophe; Liens, Benjamin; Burguière, Thomas; Hill, Véronique; Couvin, David; Millet, Julie; Mokrousov, Igor; Sola, Christophe; Zozio, Thierry; Rastogi, Nalin

    2012-06-01

    Among various genotyping methods to study Mycobacterium tuberculosis complex (MTC) genotypic polymorphism, spoligotyping and mycobacterial interspersed repetitive units-variable number of DNA tandem repeats (MIRU-VNTRs) have recently gained international approval as robust, fast, and reproducible typing methods generating data in a portable format. Spoligotyping constituted the backbone of a publicly available database SpolDB4 released in 2006; nonetheless this method possesses a low discriminatory power when used alone and should be ideally used in conjunction with a second typing method such as MIRU-VNTRs for high-resolution epidemiological studies. We hereby describe a publicly available international database named SITVITWEB which incorporates such multimarker data allowing to have a global vision of MTC genetic diversity worldwide based on 62,582 clinical isolates corresponding to 153 countries of patient origin (105 countries of isolation). We report a total of 7105 spoligotype patterns (corresponding to 58,180 clinical isolates) - grouped into 2740 shared-types or spoligotype international types (SIT) containing 53,816 clinical isolates and 4364 orphan patterns. Interestingly, only 7% of the MTC isolates worldwide were orphans whereas more than half of SITed isolates (n=27,059) were restricted to only 24 most prevalent SITs. The database also contains a total of 2379 MIRU patterns (from 8161 clinical isolates) from 87 countries of patient origin (35 countries of isolation); these were grouped in 847 shared-types or MIRU international types (MIT) containing 6626 isolates and 1533 orphan patterns. Lastly, data on 5-locus exact tandem repeats (ETRs) were available on 4626 isolates from 59 countries of patient origin (22 countries of isolation); a total of 458 different VNTR patterns were observed - split into 245 shared-types or VNTR International Types (VIT) containing 4413 isolates) and 213 orphan patterns. Datamining of SITVITWEB further allowed to update

  15. Classification, epidemiology, and genetics of orofacial clefts.

    PubMed

    Watkins, Stephanie E; Meyer, Robert E; Strauss, Ronald P; Aylsworth, Arthur S

    2014-04-01

    Orofacial clefts (OFCs) include a broad range of facial conditions that differ in cause and disease burden. In the published literature, there is substantial ambiguity in both terminology and classification of OFCs. This article discusses the terminology and classification of OFCs and the epidemiology of OFCs. Demographic, environmental, and genetic risk factors for OFCs are described, including suggestions for family counseling. This article enables clinicians to counsel families regarding the occurrence and recurrence of OFCs. Although much of the information is detailed, it is intended to be accessible to all health professionals for use in their clinical practices.

  16. Ethical issues in the use of genetic markers in occupational epidemiologic research.

    PubMed

    Schulte, P A; Lomax, G P; Ward, E M; Colligan, M J

    1999-08-01

    This review was conducted to characterize the nature of contemporary occupational epidemiologic research involving genetic markers, consider how genetic information is unique with regard to its social applications, and examine some of the ethical dilemmas that may arise over the course of studies. We have reviewed the literature and the lessons from our experience in conducting occupational epidemiologic research involving genetic markers. This review describes how occupational epidemiologic studies differ from other epidemiologic studies on issues of participation, confidentiality, and the history of including genetic markers. Of primary concern in occupational studies are genes that have multiple alleles and are sometimes referred to as "metabolic polymorphisms." They generally do not confer risk on their own but rather only in combination with a specific exposure. There is a need for a clear policy and guidelines for the conduct of occupational epidemiologic studies using genetic material. This policy should address all of the steps in study design, implementation, interpretation, and communication of results.

  17. [The epidemiology and genetics of asthma. II. Genetic aspects of the epidemiology of asthma and atopy].

    PubMed

    Demoly, P; Jaffuel, D; Bousquet, J; Godard, P; Michel, F B

    1996-12-01

    Asthma is regarded as a disease with a complex interaction between genetic and environmental factors. Since the end of the 1970s and during the 80s the world has seen an increase in the prevalence, morbidity and mortality linked to asthma. The rapidity of progress of this phenomenon means that it cannot be explained only by modification of genetic factors and stresses the preponderance of exogenous factors. The purpose of this review is to examine the epidemiological knowledge of these environmental factors and of the genetic factors in asthma in order to underline how these genetic and exogenous factors interact and modulate the occurrence of the asthmatic disease. In the first part of this general review we discussed the epidemiology of asthma in terms of prevalence, incidence, mortality, cost and socio-professional and scholastic repercussions and underlined for each environmental factor its causal role and/or exacerbation in asthma as well as its contribution in the increased prevalence and severity of asthma. In the second part of this general view we touch on the epidemiological knowledge of the genetics of asthma and of atopy.

  18. Latino Populations: A Unique Opportunity for the Study of Race, Genetics, and Social Environment in Epidemiological Research

    PubMed Central

    González Burchard, Esteban; Borrell, Luisa N.; Choudhry, Shweta; Naqvi, Mariam; Tsai, Hui-Ju; Rodriguez-Santana, Jose R.; Chapela, Rocio; Rogers, Scott D.; Mei, Rui; Rodriguez-Cintron, William; Arena, Jose F.; Kittles, Rick; Perez-Stable, Eliseo J.; Ziv, Elad; Risch, Neil

    2005-01-01

    Latinos are the largest minority population in the United States. Although usually classified as a single ethnic group by researchers, Latinos are heterogeneous from cultural, socioeconomic, and genetic perspectives. From a cultural and social perspective, Latinos represent a wide variety of national origins and ethnic and cultural groups, with a full spectrum of social class. From a genetic perspective, Latinos are descended from indigenous American, European, and African populations. We review the historical events that led to the formation of contemporary Latino populations and use results from recent genetic and clinical studies to illustrate the unique opportunity Latino groups offer for studying the interaction between racial, genetic, and environmental contributions to disease occurrence and drug response. PMID:16257940

  19. Epidemiology, genetics and treatments for myopia

    PubMed Central

    Yu, Lei; Li, Zhi-Kui; Gao, Jin-Rong; Liu, Jian-Rong; Xu, Chang-Tai

    2011-01-01

    Myopia is a significant public health problem and its prevalence is increasing over time and genetic factors in disease development are important. The prevalence and incidence of myopia within sampled population often varies with age, country, sex, race, ethnicity, occupation, environment, and other factors. Myopia growth is under a combination of genes and their products in time and space to complete the coordination role of the guidance. Myopia-related genes include about 70 genetic loci to which primary myopias have been mapped, although the number is constantly increasing and depends to some extent on definition. Of these, several are associated with additional abnormalities, mostly as part of developmental syndromes. These tend to result from mutations in genes encoding transcriptional activators, and most of these have been identified by sequencing candidate genes in patients with developmental anomalies. Currently, COL1A1 (collagen alpha-1 chain of type I), COL2A1 (collagen alpha-1 chain of type II), ACTC1 (actin, alpha, cardiac muscle 1), PAX6 (paired box gene 6) and NIPBL (nipped-B homolog), and so on have been mapped. Myopia is most commonly treated with spectacles or glasses. The most common surgical procedure performed to correct myopia is laser in situ keratomileusis (LASIK). This review of the recent advances on epidemiology, genetic locations and treatments of myopia are summarized. PMID:22553740

  20. Genetic epidemiology of primary sclerosing cholangitis

    PubMed Central

    Karlsen, Tom H; Schrumpf, Erik; Boberg, Kirsten Muri

    2007-01-01

    The aetiology of primary sclerosing cholangitis (PSC) is not known. A more than 80-fold increased risk of PSC among first-degree relatives emphasizes the importance of genetic factors. Genetic associations within the human leukocyte antigen (HLA) complex on chromosome 6p21 were detected in PSC 25 years ago. Subsequent studies have substantiated beyond doubt that one or more genetic variants located within this genetic region are important. The true identities of these variants, however, remain to be identified. Several candidate genes at other chromosomal loci have also been investigated. However, according to strict criteria for what may be denominated a susceptibility gene in complex diseases, no such gene exists for PSC today. This review summarises present knowledge on the genetic susceptibility to PSC, as well as genetic associations with disease progression and clinical subsets of particular interest (inflammatory bowel disease and cholangiocarcinoma). PMID:17907284

  1. Shared genetics underlying epidemiological association between endometriosis and ovarian cancer

    PubMed Central

    Lu, Yi; Cuellar-Partida, Gabriel; Painter, Jodie N.; Nyholt, Dale R.; Morris, Andrew P.; Fasching, Peter A.; Hein, Alexander; Burghaus, Stefanie; Beckmann, Matthias W.; Lambrechts, Diether; Van Nieuwenhuysen, Els; Vergote, Ignace; Vanderstichele, Adriaan; Doherty, Jennifer Anne; Rossing, Mary Anne; Wicklund, Kristine G.; Chang-Claude, Jenny; Eilber, Ursula; Rudolph, Anja; Wang-Gohrke, Shan; Goodman, Marc T.; Bogdanova, Natalia; Dörk, Thilo; Dürst, Matthias; Hillemanns, Peter; Runnebaum, Ingo B.; Antonenkova, Natalia; Butzow, Ralf; Leminen, Arto; Nevanlinna, Heli; Pelttari, Liisa M.; Edwards, Robert P.; Kelley, Joseph L.; Modugno, Francesmary; Moysich, Kirsten B.; Ness, Roberta B.; Cannioto, Rikki; Høgdall, Estrid; Jensen, Allan; Giles, Graham G.; Bruinsma, Fiona; Kjaer, Susanne K.; Hildebrandt, Michelle A.T.; Liang, Dong; Lu, Karen H.; Wu, Xifeng; Bisogna, Maria; Dao, Fanny; Levine, Douglas A.; Cramer, Daniel W.; Terry, Kathryn L.; Tworoger, Shelley S.; Missmer, Stacey; Bjorge, Line; Salvesen, Helga B.; Kopperud, Reidun K.; Bischof, Katharina; Aben, Katja K.H.; Kiemeney, Lambertus A.; Massuger, Leon F.A.G.; Brooks-Wilson, Angela; Olson, Sara H.; McGuire, Valerie; Rothstein, Joseph H.; Sieh, Weiva; Whittemore, Alice S.; Cook, Linda S.; Le, Nhu D.; Gilks, C. Blake; Gronwald, Jacek; Jakubowska, Anna; Lubiński, Jan; Gawełko, Jan; Song, Honglin; Tyrer, Jonathan P.; Wentzensen, Nicolas; Brinton, Louise; Trabert, Britton; Lissowska, Jolanta; Mclaughlin, John R.; Narod, Steven A.; Phelan, Catherine; Anton-Culver, Hoda; Ziogas, Argyrios; Eccles, Diana; Gayther, Simon A.; Gentry-Maharaj, Aleksandra; Menon, Usha; Ramus, Susan J.; Wu, Anna H.; Dansonka-Mieszkowska, Agnieszka; Kupryjanczyk, Jolanta; Timorek, Agnieszka; Szafron, Lukasz; Cunningham, Julie M.; Fridley, Brooke L.; Winham, Stacey J.; Bandera, Elisa V.; Poole, Elizabeth M.; Morgan, Terry K.; Risch, Harvey A.; Goode, Ellen L.; Schildkraut, Joellen M.; Webb, Penelope M.; Pearce, Celeste L.; Berchuck, Andrew; Pharoah, Paul D.P.; Montgomery, Grant W.; Zondervan, Krina T.; Chenevix-Trench, Georgia; MacGregor, Stuart

    2015-01-01

    Epidemiological studies have demonstrated associations between endometriosis and certain histotypes of ovarian cancer, including clear cell, low-grade serous and endometrioid carcinomas. We aimed to determine whether the observed associations might be due to shared genetic aetiology. To address this, we used two endometriosis datasets genotyped on common arrays with full-genome coverage (3194 cases and 7060 controls) and a large ovarian cancer dataset genotyped on the customized Illumina Infinium iSelect (iCOGS) arrays (10 065 cases and 21 663 controls). Previous work has suggested that a large number of genetic variants contribute to endometriosis and ovarian cancer (all histotypes combined) susceptibility. Here, using the iCOGS data, we confirmed polygenic architecture for most histotypes of ovarian cancer. This led us to evaluate if the polygenic effects are shared across diseases. We found evidence for shared genetic risks between endometriosis and all histotypes of ovarian cancer, except for the intestinal mucinous type. Clear cell carcinoma showed the strongest genetic correlation with endometriosis (0.51, 95% CI = 0.18–0.84). Endometrioid and low-grade serous carcinomas had similar correlation coefficients (0.48, 95% CI = 0.07–0.89 and 0.40, 95% CI = 0.05–0.75, respectively). High-grade serous carcinoma, which often arises from the fallopian tubes, showed a weaker genetic correlation with endometriosis (0.25, 95% CI = 0.11–0.39), despite the absence of a known epidemiological association. These results suggest that the epidemiological association between endometriosis and ovarian adenocarcinoma may be attributable to shared genetic susceptibility loci. PMID:26231222

  2. Shared genetics underlying epidemiological association between endometriosis and ovarian cancer.

    PubMed

    Lu, Yi; Cuellar-Partida, Gabriel; Painter, Jodie N; Nyholt, Dale R; Morris, Andrew P; Fasching, Peter A; Hein, Alexander; Burghaus, Stefanie; Beckmann, Matthias W; Lambrechts, Diether; Van Nieuwenhuysen, Els; Vergote, Ignace; Vanderstichele, Adriaan; Doherty, Jennifer Anne; Rossing, Mary Anne; Wicklund, Kristine G; Chang-Claude, Jenny; Eilber, Ursula; Rudolph, Anja; Wang-Gohrke, Shan; Goodman, Marc T; Bogdanova, Natalia; Dörk, Thilo; Dürst, Matthias; Hillemanns, Peter; Runnebaum, Ingo B; Antonenkova, Natalia; Butzow, Ralf; Leminen, Arto; Nevanlinna, Heli; Pelttari, Liisa M; Edwards, Robert P; Kelley, Joseph L; Modugno, Francesmary; Moysich, Kirsten B; Ness, Roberta B; Cannioto, Rikki; Høgdall, Estrid; Jensen, Allan; Giles, Graham G; Bruinsma, Fiona; Kjaer, Susanne K; Hildebrandt, Michelle A T; Liang, Dong; Lu, Karen H; Wu, Xifeng; Bisogna, Maria; Dao, Fanny; Levine, Douglas A; Cramer, Daniel W; Terry, Kathryn L; Tworoger, Shelley S; Missmer, Stacey; Bjorge, Line; Salvesen, Helga B; Kopperud, Reidun K; Bischof, Katharina; Aben, Katja K H; Kiemeney, Lambertus A; Massuger, Leon F A G; Brooks-Wilson, Angela; Olson, Sara H; McGuire, Valerie; Rothstein, Joseph H; Sieh, Weiva; Whittemore, Alice S; Cook, Linda S; Le, Nhu D; Gilks, C Blake; Gronwald, Jacek; Jakubowska, Anna; Lubiński, Jan; Gawełko, Jan; Song, Honglin; Tyrer, Jonathan P; Wentzensen, Nicolas; Brinton, Louise; Trabert, Britton; Lissowska, Jolanta; Mclaughlin, John R; Narod, Steven A; Phelan, Catherine; Anton-Culver, Hoda; Ziogas, Argyrios; Eccles, Diana; Gayther, Simon A; Gentry-Maharaj, Aleksandra; Menon, Usha; Ramus, Susan J; Wu, Anna H; Dansonka-Mieszkowska, Agnieszka; Kupryjanczyk, Jolanta; Timorek, Agnieszka; Szafron, Lukasz; Cunningham, Julie M; Fridley, Brooke L; Winham, Stacey J; Bandera, Elisa V; Poole, Elizabeth M; Morgan, Terry K; Risch, Harvey A; Goode, Ellen L; Schildkraut, Joellen M; Webb, Penelope M; Pearce, Celeste L; Berchuck, Andrew; Pharoah, Paul D P; Montgomery, Grant W; Zondervan, Krina T; Chenevix-Trench, Georgia; MacGregor, Stuart

    2015-10-15

    Epidemiological studies have demonstrated associations between endometriosis and certain histotypes of ovarian cancer, including clear cell, low-grade serous and endometrioid carcinomas. We aimed to determine whether the observed associations might be due to shared genetic aetiology. To address this, we used two endometriosis datasets genotyped on common arrays with full-genome coverage (3194 cases and 7060 controls) and a large ovarian cancer dataset genotyped on the customized Illumina Infinium iSelect (iCOGS) arrays (10 065 cases and 21 663 controls). Previous work has suggested that a large number of genetic variants contribute to endometriosis and ovarian cancer (all histotypes combined) susceptibility. Here, using the iCOGS data, we confirmed polygenic architecture for most histotypes of ovarian cancer. This led us to evaluate if the polygenic effects are shared across diseases. We found evidence for shared genetic risks between endometriosis and all histotypes of ovarian cancer, except for the intestinal mucinous type. Clear cell carcinoma showed the strongest genetic correlation with endometriosis (0.51, 95% CI = 0.18-0.84). Endometrioid and low-grade serous carcinomas had similar correlation coefficients (0.48, 95% CI = 0.07-0.89 and 0.40, 95% CI = 0.05-0.75, respectively). High-grade serous carcinoma, which often arises from the fallopian tubes, showed a weaker genetic correlation with endometriosis (0.25, 95% CI = 0.11-0.39), despite the absence of a known epidemiological association. These results suggest that the epidemiological association between endometriosis and ovarian adenocarcinoma may be attributable to shared genetic susceptibility loci.

  3. The CoLaus study: a population-based study to investigate the epidemiology and genetic determinants of cardiovascular risk factors and metabolic syndrome

    PubMed Central

    Firmann, Mathieu; Mayor, Vladimir; Vidal, Pedro Marques; Bochud, Murielle; Pécoud, Alain; Hayoz, Daniel; Paccaud, Fred; Preisig, Martin; Song, Kijoung S; Yuan, Xin; Danoff, Theodore M; Stirnadel, Heide A; Waterworth, Dawn; Mooser, Vincent; Waeber, Gérard; Vollenweider, Peter

    2008-01-01

    Background Cardiovascular diseases and their associated risk factors remain the main cause of mortality in western societies. In order to assess the prevalence of cardiovascular risk factors (CVRFs) in the Caucasian population of Lausanne, Switzerland, we conducted a population-based study (Colaus Study). A secondary aim of the CoLaus study will be to determine new genetic determinants associated with CVRFs. Methods Single-center, cross-sectional study including a random sample of 6,188 extensively phenotyped Caucasian subjects (3,251 women and 2,937 men) aged 35 to 75 years living in Lausanne, and genotyped using the 500 K Affymetrix chip technology. Results Obesity (body mass index ≥ 30 kg/m2), smoking, hypertension (blood pressure ≥ 140/90 mmHg and/or treatment), dyslipidemia (high LDL-cholesterol and/or low HDL-cholesterol and/or high triglyceride levels) and diabetes (fasting plasma glucose ≥ 7 mmol/l and/or treatment) were present in 947 (15.7%), 1673 (27.0%), 2268 (36.7%), 2113 (34.2%) and 407 (6.6%) of the participants, respectively, and the prevalence was higher in men than in women. In both genders, the prevalence of obesity, hypertension and diabetes increased with age. Conclusion The prevalence of major CVRFs is high in the Lausanne population in particular in men. We anticipate that given its size, the depth of the phenotypic analysis and the availability of dense genome-wide genetic data, the CoLaus Study will be a unique resource to investigate not only the epidemiology of isolated, or aggregated CVRFs like the metabolic syndrome, but can also serve as a discovery set, as well as replication set, to identify novel genes associated with these conditions. PMID:18366642

  4. Twin Studies: A Unique Epidemiological Tool

    PubMed Central

    Sahu, Monalisha; Prasuna, Josyula G

    2016-01-01

    Twin studies are a special type of epidemiological studies designed to measure the contribution of genetics as opposed to the environment, to a given trait. Despite the facts that the classical twin studies are still being guided by assumptions made back in the 1920s and that the inherent limitation lies in the study design itself, the results suggested by earlier twin studies have often been confirmed by molecular genetic studies later. Use of twin registries and various innovative yet complex software packages such as the (SAS) and their extensions (e.g., SAS PROC GENMOD and SAS PROC PHREG) has increased the potential of this epidemiological tool toward contributing significantly to the field of genetics and other life sciences. PMID:27385869

  5. Genetic epidemiology of left ventricular hypertrophy

    PubMed Central

    Bella, Jonathan N; Göring, Harald HH

    2012-01-01

    Left ventricular (LV) hypertrophy is a strong independent predictor of increased cardiovascular morbidity and mortality in clinical and population-based samples. Clinical and hemodynamic stimuli to LV hypertrophy induce not only an increase in cardiac mass and wall thickness but also a fundamental reconfiguration of the protein, cellular and molecular components of the myocardium. Several studies have indicated that LV mass is influenced by genetic factors. The substantial heritability (h2) for LV mass in population-based samples of varying ethnicity indicates robust genetic influences on LV hypertrophy. Genome-wide linkage and association studies in diverse populations have been performed to identify genes influencing LV mass, and although several chromosomal regions have been found to be significantly associated with LV mass, the specific genes and functional variants contained in these chromosomal regions have yet to be identified. In addition, multiple studies have tried to link single-nucleotide polymorphisms (SNPs) in regulatory and pathway genes with common forms of LV hypertrophy, but there is little evidence that these genetic variations are functional. Up to this point in time, the results obtained in genetic studies are of limited clinical value. Much of the heritability remains unexplained, the identity of the underlying gene pathways, genes, and functional variants remains unknown, and the promise of genetically-based risk prediction and personalized medicine remain unfulfilled. However, molecular biological technologies continue to improve rapidly, and the long-term potential of sophisticated genetic investigations using these modern genomic technologies, coupled with smart study designs, remains intact. Ultimately, genetic investigations offer much promise for future prevention, early intervention and treatment of this major public health issue. PMID:23173100

  6. A Comprehensive Study on the Etiology of Patients Receiving Cochlear Implantation With Special Emphasis on Genetic Epidemiology

    PubMed Central

    Miyagawa, Maiko; Nishio, Shin-Ya; Usami, Shin-Ichi

    2016-01-01

    Objective: Cochlear implantation is the most important treatment currently available for profound sensorineural hearing loss. The aim of this study was to investigate the etiology of hearing loss in patients with cochlear implantation, and to compare outcomes. Methods: Japanese hearing loss patients who received cochlear implants (CIs) or electric acoustic stimulation (EAS) in Shinshu University hospital (n = 173, prelingual onset: 92, postlingual onset: 81) participated in this study. Invader assay followed by the targeted exon-sequencing of 63 deafness genes using Massively parallel DNA sequencing (MPS) was applied. For prelingual patients, additional imaging examination, cCMV screening, and pediatric examination were performed for precise diagnosis. Results: Genetic screening successfully identified the causative mutation in 60% of patients with prelingual onset hearing loss and in 36% of those with postlingual hearing loss. Differences in the kinds of genes identified were observed between the two groups. Although there were marked variations in the outcome of cochlear implantation, patients with specific deafness gene mutations showed relatively good results. Conclusion: The present study showed genetic etiology is a major cause of hearing loss in CI/EAS patients. Patients possessing mutations in a number of deafness genes known to be expressed within inner ear have achieved satisfactory auditory performance, suggesting that the identification of the genetic background facilitates the prediction of post-CI performance. MPS is a powerful tool for the identification of causative deafness genes in patients receiving cochlear implantation. Therefore, determination of the involved region inside/outside of the cochlea by identification of the responsible gene is essential. PMID:26756145

  7. Genetic epidemiology of irritable bowel syndrome.

    PubMed

    Makker, Jasbir; Chilimuri, Sridhar; Bella, Jonathan N

    2015-10-28

    Irritable bowel syndrome (IBS) is the most common functional gastrointestinal disorder characterized by presence of abdominal pain or discomfort associated with altered bowel habits. It has three main subtypes - constipation predominant IBS (C-IBS), diarrhea predominant IBS (D-IBS) and IBS with mixed features of both diarrhea as well as constipation (M-IBS). Its pathophysiology and underlying mechanisms remain elusive. It is traditionally believed that IBS is a result of multiple factors including hypersensitivity of the bowel, altered bowel motility, inflammation and stress. Initial studies have shown familial aggregation of IBS suggesting shared genetic or environmental factors. Twin studies of IBS from different parts of world have shown higher concordance rates among monozygotic twins than dizygotic twins, and thus suggesting a genetic component to this disorder. Multiple studies have tried to link single-nucleotide polymorphisms (SNPs) to IBS but there is little evidence that these SNPs are functional. Various molecules have been studied and investigated by the researchers. Serotonin, a known neurotransmitter and a local hormone in the enteric nervous system, has been most extensively explored. At this time, the underlying gene pathways, genes and functional variants linked with IBS remain unknown and the promise of genetically-determined risk prediction and personalize medicine remain unfulfilled. However, molecular biological technologies continue to evolve rapidly and genetic investigations offer much promise in the intervention, treatment and prevention of IBS. PMID:26525775

  8. Longitudinal relationships between glycemic status and body mass index in a multiethnic study: evidence from observational and genetic epidemiology

    PubMed Central

    Ishola, Adeola F.; Gerstein, Hertzel C.; Engert, James C.; Mohan, Viswanathan; Diaz, Rafael; Anand, Sonia S.; Meyre, David

    2016-01-01

    We investigated the relationship between glycemic status and BMI and its interaction with obesity single-nucleotide polymorphisms (SNPs) in a multi-ethnic longitudinal cohort at high-risk for dysglycemia. We studied 17 394 participants from six ethnicities followed-up for 3.3 years. Twenty-three obesity SNPs were genotyped and an unweighted genotype risk score (GRS) was calculated. Glycemic status was defined using an oral glucose tolerance test. Linear regression models were adjusted for age, sex and population stratification. Normal glucose tolerance (NGT) to dysglycemia transition was associated with baseline BMI and BMI change. Impaired fasting glucose/impaired glucose tolerance to type 2 diabetes transition was associated with baseline BMI but not BMI change. No simultaneous significant main genetic effects and interactions between SNPs/GRS and glycemic status or transition on BMI level and BMI change were observed. Our data suggests that the interplay between glycemic status and BMI trajectory may be independent of the effects of obesity genes. This implies that individuals with different glycemic statuses may be combined together in genetic association studies on obesity traits, if appropriate adjustments for glycemic status are performed. Implementation of population-wide weight management programs may be more beneficial towards individuals with NGT than those at a later disease stage. PMID:27480816

  9. Longitudinal relationships between glycemic status and body mass index in a multiethnic study: evidence from observational and genetic epidemiology.

    PubMed

    Ishola, Adeola F; Gerstein, Hertzel C; Engert, James C; Mohan, Viswanathan; Diaz, Rafael; Anand, Sonia S; Meyre, David

    2016-01-01

    We investigated the relationship between glycemic status and BMI and its interaction with obesity single-nucleotide polymorphisms (SNPs) in a multi-ethnic longitudinal cohort at high-risk for dysglycemia. We studied 17 394 participants from six ethnicities followed-up for 3.3 years. Twenty-three obesity SNPs were genotyped and an unweighted genotype risk score (GRS) was calculated. Glycemic status was defined using an oral glucose tolerance test. Linear regression models were adjusted for age, sex and population stratification. Normal glucose tolerance (NGT) to dysglycemia transition was associated with baseline BMI and BMI change. Impaired fasting glucose/impaired glucose tolerance to type 2 diabetes transition was associated with baseline BMI but not BMI change. No simultaneous significant main genetic effects and interactions between SNPs/GRS and glycemic status or transition on BMI level and BMI change were observed. Our data suggests that the interplay between glycemic status and BMI trajectory may be independent of the effects of obesity genes. This implies that individuals with different glycemic statuses may be combined together in genetic association studies on obesity traits, if appropriate adjustments for glycemic status are performed. Implementation of population-wide weight management programs may be more beneficial towards individuals with NGT than those at a later disease stage. PMID:27480816

  10. [The Human Genome Project, genetic viability and genetic epidemiology].

    PubMed

    Hagymási, Krisztina; Tulassay, Zsolt

    2005-12-18

    The goal of the Human Genome Project to elucidate the complete sequence of the human genome has been achieved. The aims of the "post-genome" era are explaining the genetic information, characterisation of functional elements encoded in the human genome and mapping the human genetic variability as well. Two unrelated human beings also share 99.9% of their genomic sequence. The difference of 0.1% is the result of genetic polymorphisms: single nucleotide polymorphisms, repetitive sequences and insertion/deletion. The genetic differences, coupled with environmental exposures will determine the phenotypic variation we observe in health or disease. The disease-causing genetic variants can be identified by linkage analysis or association studies. The knowledge of human genome and application of multiple biomarkers will improve our ability to identify individuals at risk, so that preventive interventions can be applied, earlier diagnosis can be made and treatment can be optimized.

  11. Genotyping of Mycobacterium tuberculosis: application in epidemiologic studies

    PubMed Central

    Kato-Maeda, Midori; Metcalfe, John Z.; Flores, Laura

    2014-01-01

    Genotyping is used to track specific isolates of Mycobacterium tuberculosis in a community. It has been successfully used in epidemiologic research (termed ‘molecular epidemiology’) to study the transmission dynamics of TB. In this article, we review the genetic markers used in molecular epidemiologic studies including the use of whole-genome sequencing technology. We also review the public health application of molecular epidemiologic tools. PMID:21366420

  12. Bacterial population genetics, evolution and epidemiology.

    PubMed Central

    Spratt, B G; Maiden, M C

    1999-01-01

    Asexual bacterial populations inevitably consist of an assemblage of distinct clonal lineages. However, bacterial populations are not entirely asexual since recombinational exchanges occur, mobilizing small genome segments among lineages and species. The relative contribution of recombination, as opposed to de novo mutation, in the generation of new bacterial genotypes varies among bacterial populations and, as this contribution increases, the clonality of a given population decreases. In consequence, a spectrum of possible population structures exists, with few bacterial species occupying the extremes of highly clonal and completely non-clonal, most containing both clonal and non-clonal elements. The analysis of collections of bacterial isolates, which accurately represent the natural population, by nucleotide sequence determination of multiple housekeeping loci provides data that can be used both to investigate the population structure of bacterial pathogens and for the molecular characterization of bacterial isolates. Understanding the population structure of a given pathogen is important since it impacts on the questions that can be addressed by, and the methods and samples required for, effective molecular epidemiological studies. PMID:10365396

  13. Genetic epidemiology of pelvic organ prolapse: a systematic review.

    PubMed

    Ward, Renée M; Velez Edwards, Digna R; Edwards, Todd; Giri, Ayush; Jerome, Rebecca N; Wu, Jennifer M

    2014-10-01

    Given current evidence supporting a genetic predisposition for pelvic organ prolapse, we conducted a systematic review of published literature on the genetic epidemiology of pelvic organ prolapse. Inclusion criteria were linkage studies, candidate gene association and genome-wide association studies in adult women published in English and indexed in PubMed through Dec. 2012, with no limit on date of publication. Methodology adhered to the PRISMA guidelines. Data were systematically extracted by 2 reviewers and graded by the Venice criteria for studies of genetic associations. A metaanalysis was performed on all single nucleotide polymorphisms evaluated by 2 or more studies with similar methodology. The metaanalysis suggests that collagen type 3 alpha 1 (COL3A1) rs1800255 genotype AA is associated with pelvic organ prolapse (odds ratio, 4.79; 95% confidence interval, 1.91-11.98; P = .001) compared with the reference genotype GG in populations of Asian and Dutch women. There was little evidence of heterogeneity for rs1800255 (P value for heterogeneity = .94; proportion of variance because of heterogeneity, I(2) = 0.00%). There was insufficient evidence to determine whether other single nucleotide polymorphisms evaluated by 2 or more papers were associated with pelvic organ prolapse. An association with pelvic organ prolapse was seen in individual studies for estrogen receptor alpha (ER-α) rs2228480 GA, COL3A1 exon 31, chromosome 9q21 (heterogeneity logarithm of the odds score 3.41) as well as 6 single nucleotide polymorphisms identified by a genome-wide association study. Overall, individual studies were of small sample size and often of poor quality. Future studies would benefit from more rigorous study design as outlined in the Venice recommendations. PMID:24721264

  14. Linkage of Type 2 Diabetes on Chromosome 9p24 in Mexican Americans: Additional Evidence from the Veterans Administration Genetic Epidemiology Study (VAGES)

    PubMed Central

    Farook, Vidya S.; Coletta, Dawn K.; Puppala, Sobha; Schneider, Jennifer; Chittoor, Geetha; Hu, Shirley L.; Winnier, Deidre A.; Norton, Luke; Dyer, Thomas D.; Arya, Rector; Cole, Shelley A.; Carless, Melanie; Göring, Harald H.; Almasy, Laura; Mahaney, Michael C.; Comuzzie, Anthony G.; Curran, Joanne E.; Blangero, John; Duggirala, Ravindranath; Lehman, Donna M.; Jenkinson, Christopher P.; DeFronzo, Ralph A.

    2014-01-01

    Objective Type 2 diabetes (T2DM) is a complex metabolic disease and is more prevalent in certain ethnic groups such as the Mexican Americans. The goal of our study was to perform a genome-wide linkage analysis to localize T2DM susceptibility loci in Mexican Americans. Methods We used the phenotypic and genotypic data from 1,122 Mexican American individuals (307 families) who participated in the Veterans Administration Genetic Epidemiology Study (VAGES). Genome-wide linkage analysis was performed, using the variance components approach. Data from two additional Mexican American family studies, the San Antonio Family Heart Study (SAFHS) and the San Antonio Family Diabetes/Gallbladder Study (SAFDGS), were combined with the VAGES data to test for improved linkage evidence. Results After adjusting for covariate effects, T2DM was found to be under significant genetic influences (h2 = 0.62, P = 2.7 × 10−6). The strongest evidence for linkage of T2DM occurred between markers D9S1871 and D9S2169 on chromosome 9p24.2-p24.1 (LOD = 1.8). Given that we previously reported suggestive evidence for linkage of T2DM at this region in SAFDGS also, we found the significant and increased linkage evidence (LOD = 4.3, empirical P = 1.0 × 10−5, genome-wide P = 1.6 × 10−3) for T2DM at the same chromosomal region when we performed genome-wide linkage analysis of the VAGES data combined with SAFHS and SAFDGS data. Conclusion Significant T2DM linkage evidence was found on chromosome 9p24 in Mexican Americans. Importantly, the chromosomal region of interest in this study overlaps with several recent genome-wide association studies (GWASs) involving T2DM related traits. Given its overlap with such findings and our own initial T2DM association findings in the 9p24 chromosomal region, high throughput sequencing of the linked chromosomal region could identify the potential causal T2DM genes. PMID:24060607

  15. Genetic Epidemiology of Pelvic Organ Prolapse: A Systematic Review

    PubMed Central

    WARD, Renée M.; VELEZ EDWARDS, Digna R.; EDWARDS, Todd; GIRI, Ayush; JEROME, Rebecca N.; WU, Jennifer M.

    2014-01-01

    Given current evidence supporting a genetic predisposition for pelvic organ prolapse (POP), we conducted a systematic review of published literature on the genetic epidemiology of POP. Inclusion criteria were linkage studies, candidate gene association and genome-wide association studies (GWAS) in adult women published in English and indexed in PubMed through December 2012, with no limit on date of publication. Methodology adhered to the PRISMA guidelines. Data were systematically extracted by two reviewers and graded by the Venice criteria for studies of genetic associations. A meta-analysis was performed on all single nucleotide polymorphisms (SNPs) evaluated by two or more studies with similar methodology. The meta-analysis suggests that collagen type 3 alpha 1 (COL3A1) rs1800255 genotype AA is associated with POP, OR 4.79 (95% CI 1.91 to 11.98, p= 0.001) compared to the reference genotype GG in populations of Asian and Dutch women. There was little evidence of heterogeneity for rs1800255 (p-value for heterogeneity= 0.94; proportion of variance due to heterogeneity, I2= 0.00%). There was insufficient evidence to determine whether other SNPs evaluated by two or more papers were associated with POP. An association with POP was seen in individual studies for estrogen receptor alpha (ER-α) rs2228480 GA, COL3A1 exon 31, chromosome 9q21 (HLOD score 3.41) as well as six SNPs identified by a GWAS. Overall, individual studies were of small sample size and often of poor quality. Future studies would benefit from more rigorous study design as outlined in the Venice recommendations. PMID:24721264

  16. Epidemiology, Genetic Recombination, and Pathogenesis of Coronaviruses.

    PubMed

    Su, Shuo; Wong, Gary; Shi, Weifeng; Liu, Jun; Lai, Alexander C K; Zhou, Jiyong; Liu, Wenjun; Bi, Yuhai; Gao, George F

    2016-06-01

    Human coronaviruses (HCoVs) were first described in the 1960s for patients with the common cold. Since then, more HCoVs have been discovered, including those that cause severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS), two pathogens that, upon infection, can cause fatal respiratory disease in humans. It was recently discovered that dromedary camels in Saudi Arabia harbor three different HCoV species, including a dominant MERS HCoV lineage that was responsible for the outbreaks in the Middle East and South Korea during 2015. In this review we aim to compare and contrast the different HCoVs with regard to epidemiology and pathogenesis, in addition to the virus evolution and recombination events which have, on occasion, resulted in outbreaks amongst humans.

  17. Epidemiology, Genetic Recombination, and Pathogenesis of Coronaviruses.

    PubMed

    Su, Shuo; Wong, Gary; Shi, Weifeng; Liu, Jun; Lai, Alexander C K; Zhou, Jiyong; Liu, Wenjun; Bi, Yuhai; Gao, George F

    2016-06-01

    Human coronaviruses (HCoVs) were first described in the 1960s for patients with the common cold. Since then, more HCoVs have been discovered, including those that cause severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS), two pathogens that, upon infection, can cause fatal respiratory disease in humans. It was recently discovered that dromedary camels in Saudi Arabia harbor three different HCoV species, including a dominant MERS HCoV lineage that was responsible for the outbreaks in the Middle East and South Korea during 2015. In this review we aim to compare and contrast the different HCoVs with regard to epidemiology and pathogenesis, in addition to the virus evolution and recombination events which have, on occasion, resulted in outbreaks amongst humans. PMID:27012512

  18. A unifying theory for genetic epidemiological analysis of binary disease data

    PubMed Central

    2014-01-01

    Background Genetic selection for host resistance offers a desirable complement to chemical treatment to control infectious disease in livestock. Quantitative genetics disease data frequently originate from field studies and are often binary. However, current methods to analyse binary disease data fail to take infection dynamics into account. Moreover, genetic analyses tend to focus on host susceptibility, ignoring potential variation in infectiousness, i.e. the ability of a host to transmit the infection. This stands in contrast to epidemiological studies, which reveal that variation in infectiousness plays an important role in the progression and severity of epidemics. In this study, we aim at filling this gap by deriving an expression for the probability of becoming infected that incorporates infection dynamics and is an explicit function of both host susceptibility and infectiousness. We then validate this expression according to epidemiological theory and by simulating epidemiological scenarios, and explore implications of integrating this expression into genetic analyses. Results Our simulations show that the derived expression is valid for a range of stochastic genetic-epidemiological scenarios. In the particular case of variation in susceptibility only, the expression can be incorporated into conventional quantitative genetic analyses using a complementary log-log link function (rather than probit or logit). Similarly, if there is moderate variation in both susceptibility and infectiousness, it is possible to use a logarithmic link function, combined with an indirect genetic effects model. However, in the presence of highly infectious individuals, i.e. super-spreaders, the use of any model that is linear in susceptibility and infectiousness causes biased estimates. Thus, in order to identify super-spreaders, novel analytical methods using our derived expression are required. Conclusions We have derived a genetic-epidemiological function for quantitative

  19. [Lichen striatus. Epidemiologic study].

    PubMed

    Sittart, J A; Pegas, J R; Sant'Ana, L A; Pires, M C

    1989-01-01

    The authors are showing a retrospective study of 53 cases of lichen striatus concerning sex, colour, age, place of lesions, associated diseases and period of the year of occurrence of the dermatosis. There was a larger number of cases in females of white race and age-between 2 and 5 years old. A greater occurrence was observed in the months of September and March which correspond to spring and summer. Adding the fact that there have been more cases in children, at times in brothers and the trend to spontaneous involution, the authors suggest the possibility of a virus as etiology to this entity. PMID:2666785

  20. Apocalypse...now? Molecular epidemiology, predictive genetic tests, and social communication of genetic contents.

    PubMed

    Castiel, L D

    1999-01-01

    The author analyzes the underlying theoretical aspects in the construction of the molecular watershed of epidemiology and the concept of genetic risk, focusing on issues raised by contemporary reality: new technologies, globalization, proliferation of communications strategies, and the dilution of identity matrices. He discusses problems pertaining to the establishment of such new interdisciplinary fields as molecular epidemiology and molecular genetics. Finally, he analyzes the repercussions of the social communication of genetic content, especially as related to predictive genetic tests and cloning of animals, based on triumphal, deterministic metaphors sustaining beliefs relating to the existence and supremacy of concepts such as 'purity', 'essence', and 'unification' of rational, integrated 'I's/egos'. PMID:10089550

  1. Genome-wide association study of white blood cell count in 16,388 African Americans: the continental origins and genetic epidemiology network (COGENT).

    PubMed

    Reiner, Alexander P; Lettre, Guillaume; Nalls, Michael A; Ganesh, Santhi K; Mathias, Rasika; Austin, Melissa A; Dean, Eric; Arepalli, Sampath; Britton, Angela; Chen, Zhao; Couper, David; Curb, J David; Eaton, Charles B; Fornage, Myriam; Grant, Struan F A; Harris, Tamara B; Hernandez, Dena; Kamatini, Naoyuki; Keating, Brendan J; Kubo, Michiaki; LaCroix, Andrea; Lange, Leslie A; Liu, Simin; Lohman, Kurt; Meng, Yan; Mohler, Emile R; Musani, Solomon; Nakamura, Yusuke; O'Donnell, Christopher J; Okada, Yukinori; Palmer, Cameron D; Papanicolaou, George J; Patel, Kushang V; Singleton, Andrew B; Takahashi, Atsushi; Tang, Hua; Taylor, Herman A; Taylor, Kent; Thomson, Cynthia; Yanek, Lisa R; Yang, Lingyao; Ziv, Elad; Zonderman, Alan B; Folsom, Aaron R; Evans, Michele K; Liu, Yongmei; Becker, Diane M; Snively, Beverly M; Wilson, James G

    2011-06-01

    Total white blood cell (WBC) and neutrophil counts are lower among individuals of African descent due to the common African-derived "null" variant of the Duffy Antigen Receptor for Chemokines (DARC) gene. Additional common genetic polymorphisms were recently associated with total WBC and WBC sub-type levels in European and Japanese populations. No additional loci that account for WBC variability have been identified in African Americans. In order to address this, we performed a large genome-wide association study (GWAS) of total WBC and cell subtype counts in 16,388 African-American participants from 7 population-based cohorts available in the Continental Origins and Genetic Epidemiology Network. In addition to the DARC locus on chromosome 1q23, we identified two other regions (chromosomes 4q13 and 16q22) associated with WBC in African Americans (P<2.5×10(-8)). The lead SNP (rs9131) on chromosome 4q13 is located in the CXCL2 gene, which encodes a chemotactic cytokine for polymorphonuclear leukocytes. Independent evidence of the novel CXCL2 association with WBC was present in 3,551 Hispanic Americans, 14,767 Japanese, and 19,509 European Americans. The index SNP (rs12149261) on chromosome 16q22 associated with WBC count is located in a large inter-chromosomal segmental duplication encompassing part of the hydrocephalus inducing homolog (HYDIN) gene. We demonstrate that the chromosome 16q22 association finding is most likely due to a genotyping artifact as a consequence of sequence similarity between duplicated regions on chromosomes 16q22 and 1q21. Among the WBC loci recently identified in European or Japanese populations, replication was observed in our African-American meta-analysis for rs445 of CDK6 on chromosome 7q21 and rs4065321 of PSMD3-CSF3 region on chromosome 17q21. In summary, the CXCL2, CDK6, and PSMD3-CSF3 regions are associated with WBC count in African American and other populations. We also demonstrate that large inter-chromosomal duplications can

  2. Epidemiological studies in psychosomatic medicine.

    PubMed

    Eastwood, M R

    1975-01-01

    The epidemiological triad of host, agent and environment used conceptually in infectious disease may serve as a model for psychosomatic disorders, despite the involvement of many more variables. There are major problems with diagnosis and measurement, however, and the term "psychosomatic" has several meanings. The two main senses are "specific" psychosomatic disorders and an ecological view of illness. The association between psychiatric and physical disorder has been examined in a variety of settings and the findings have suggested that there is a positive relationship. Despite considerable methodological and sampling difficulties in epidemiological research into psychosomatic illness, recent efforts have been made to overcome these. The results of ecological studies appear to be more consistent that those dealing with "specific" psychosomatic disorders and suggest that man has a general psychophysical propensity to disease. Although physical and mental illness do seem to be intimately linked, the reasons for "vulnerability" to illness and "clustering" of illness are obscure. The clarification of these areas appears to be the main task ahead for epidemiology in the field of psychosomatic medicine. PMID:773850

  3. Genetic epidemiology of single-nucleotide polymorphisms.

    PubMed

    Collins, A; Lonjou, C; Morton, N E

    1999-12-21

    On the causal hypothesis, most genetic determinants of disease are single-nucleotide polymorphisms (SNPs) that are likely to be selected as markers for positional cloning. On the proximity hypothesis, most disease determinants will not be included among markers but may be detected through linkage disequilibrium with other SNPs. In that event, allelic association among SNPs is an essential factor in positional cloning. Recent simulation based on monotonic population expansion suggests that useful association does not usually extend beyond 3 kb. This is contradicted by significant disequilibrium at much greater distances, with corresponding reduction in the number of SNPs required for a cost-effective genome scan. A plausible explanation is that cyclical expansions follow population bottlenecks that establish new disequilibria. Data on more than 1,000 locus pairs indicate that most disequilibria trace to the Neolithic, with no apparent difference between haplotypes that are random or selected through a major disease gene. Short duration may be characteristic of alleles contributing to disease susceptibility and haplotypes characteristic of particular ethnic groups. Alleles that are highly polymorphic in all ethnic groups may be older, neutral, or advantageous, in weak disequilibrium with nearby markers, and therefore less useful for positional cloning of disease genes. Significant disequilibrium at large distance makes the number of suitably chosen SNPs required for genome screening as small as 30,000, or 1 per 100 kb, with greater density (including less common SNPs) reserved for candidate regions.

  4. Use of various genetic markers in differentiation of Mycobacterium bovis strains from animals and humans and for studying epidemiology of bovine tuberculosis.

    PubMed

    van Soolingen, D; de Haas, P E; Haagsma, J; Eger, T; Hermans, P W; Ritacco, V; Alito, A; van Embden, J D

    1994-10-01

    One hundred fifty-three Mycobacterium bovis strains from cattle, various animal species from zoos and wild parks, and humans were analyzed for three different genetic markers for use in the epidemiology of bovine tuberculosis. M. bovis strains isolated from cattle were found to carry a single IS6110 element, whereas the majority of strains from other animals such as antelopes, monkeys, and seals harbored multiple IS6110 elements, suggesting that the reservoirs in cattle and wild animals are separated. Because the single IS6110 element in cattle strains is located at the same chromosomal position, strain differentiation by insertion sequence fingerprinting was hampered. Therefore, we investigated the usefulness of the direct repeat and polymorphic GC-rich repeat elements for strain differentiation. Both markers allowed sufficient strain discrimination for epidemiological purposes. Evidence is presented that in Argentina, most human M. bovis infections are due to transmission from cattle, whereas M. bovis infections among humans in the Netherlands are mainly contracted from animals other than cattle. Various outbreaks of M. bovis among animals and humans are described, including a small one which likely involved transmission from human to human.

  5. Epidemiologic and Genetic Aspects of Spina Bifida and Other Neural Tube Defects

    ERIC Educational Resources Information Center

    Au, Kit Sing; Ashley-Koch, Allison; Northrup, Hope

    2010-01-01

    The worldwide incidence of neural tube defects (NTDs) ranges from 1.0 to 10.0 per 1,000 births with almost equal frequencies between two major categories: anencephaly and spina bifida (SB). Epidemiological studies have provided valuable insight for (a) researchers to identify nongenetic and genetic factors contributing to etiology, (b) public…

  6. Genetic epidemiology of single gene defects in Chile.

    PubMed Central

    Cruz-Coke, R; Moreno, R S

    1994-01-01

    We have studied the correlation between the ethnic structure and the prevalence of single gene defects in Chile. At present the Chilean population is approximately 64% white and 35% Amerindian with traces of other admixture. Fewer than 4% of the Chilean population are foreign born. Investigations indicate that all severe diseases and many others without impaired reproduction have mutation rates within the range of the white population. Classical ethnic diseases are very rare. Autosomal recessive disorders have a wide range of variability: cystic fibrosis has a low incidence and PKU has a similar incidence to English rates. Only 30% of the inborn errors of metabolism have been described in Chilean medical publications. In addition, no Chilean haemoglobin or haptoglobin variants have been described. Some rare inherited diseases in Chilean human isolates have been described, including achromatopsia, chondrocalcinosis, and Creutzfeldt-Jakob disease. The prevalence of intrahepatic cholestasis of pregnancy and supernumerary nipples is the highest in the world and they are associated with aboriginal origin. Single gene defects in Chile are probably shaped by factors related to its ethnic population structure. These local rare single gene defects may be good markers of population admixture for genetic epidemiological studies. PMID:7815439

  7. The epidemiology and genetics of binge eating disorder (BED).

    PubMed

    Davis, Caroline

    2015-12-01

    This narrative review provides an overview of the epidemiology of binge eating disorder (BED), highlighting the medical history of this disorder and its entry as an independent condition in the Feeding and Eating Disorders section of the recently published Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition. Estimates of prevalence are provided, as well as recognition that the female to male ratio is lower in BED than in other eating disorders. Evidence is also provided of the most common comorbidities of BED, including mood and anxiety disorders and a range of addiction disorders. In addition, discussion of the viewpoint that BED itself may be an addiction - at least in severe cases - is presented. Although the genetic study of BED is still in its infancy, current research is reviewed with a focus on certain neurotransmitter genes that regulate brain reward mechanisms. To date, a focal point of this research has been on the dopamine and the μ-opioid receptor genes. Preliminary evidence suggests that a predisposing risk factor for BED may be a heightened sensitivity to reward, which could manifest as a strong dopamine signal in the brain's striatal region. Caution is encouraged, however, in the interpretation of current findings, since samples are relatively small in much of the research. To date, no genome-wide association studies have focused exclusively on BED.

  8. Zika virus in the Americas: Early epidemiological and genetic findings.

    PubMed

    Faria, Nuno Rodrigues; Azevedo, Raimunda do Socorro da Silva; Kraemer, Moritz U G; Souza, Renato; Cunha, Mariana Sequetin; Hill, Sarah C; Thézé, Julien; Bonsall, Michael B; Bowden, Thomas A; Rissanen, Ilona; Rocco, Iray Maria; Nogueira, Juliana Silva; Maeda, Adriana Yurika; Vasami, Fernanda Giseli da Silva; Macedo, Fernando Luiz de Lima; Suzuki, Akemi; Rodrigues, Sueli Guerreiro; Cruz, Ana Cecilia Ribeiro; Nunes, Bruno Tardeli; Medeiros, Daniele Barbosa de Almeida; Rodrigues, Daniela Sueli Guerreiro; Nunes Queiroz, Alice Louize; da Silva, Eliana Vieira Pinto; Henriques, Daniele Freitas; Travassos da Rosa, Elisabeth Salbe; de Oliveira, Consuelo Silva; Martins, Livia Caricio; Vasconcelos, Helena Baldez; Casseb, Livia Medeiros Neves; Simith, Darlene de Brito; Messina, Jane P; Abade, Leandro; Lourenço, José; Carlos Junior Alcantara, Luiz; de Lima, Maricélia Maia; Giovanetti, Marta; Hay, Simon I; de Oliveira, Rodrigo Santos; Lemos, Poliana da Silva; de Oliveira, Layanna Freitas; de Lima, Clayton Pereira Silva; da Silva, Sandro Patroca; de Vasconcelos, Janaina Mota; Franco, Luciano; Cardoso, Jedson Ferreira; Vianez-Júnior, João Lídio da Silva Gonçalves; Mir, Daiana; Bello, Gonzalo; Delatorre, Edson; Khan, Kamran; Creatore, Marisa; Coelho, Giovanini Evelim; de Oliveira, Wanderson Kleber; Tesh, Robert; Pybus, Oliver G; Nunes, Marcio R T; Vasconcelos, Pedro F C

    2016-04-15

    Brazil has experienced an unprecedented epidemic of Zika virus (ZIKV), with ~30,000 cases reported to date. ZIKV was first detected in Brazil in May 2015, and cases of microcephaly potentially associated with ZIKV infection were identified in November 2015. We performed next-generation sequencing to generate seven Brazilian ZIKV genomes sampled from four self-limited cases, one blood donor, one fatal adult case, and one newborn with microcephaly and congenital malformations. Results of phylogenetic and molecular clock analyses show a single introduction of ZIKV into the Americas, which we estimated to have occurred between May and December 2013, more than 12 months before the detection of ZIKV in Brazil. The estimated date of origin coincides with an increase in air passengers to Brazil from ZIKV-endemic areas, as well as with reported outbreaks in the Pacific Islands. ZIKV genomes from Brazil are phylogenetically interspersed with those from other South American and Caribbean countries. Mapping mutations onto existing structural models revealed the context of viral amino acid changes present in the outbreak lineage; however, no shared amino acid changes were found among the three currently available virus genomes from microcephaly cases. Municipality-level incidence data indicate that reports of suspected microcephaly in Brazil best correlate with ZIKV incidence around week 17 of pregnancy, although this correlation does not demonstrate causation. Our genetic description and analysis of ZIKV isolates in Brazil provide a baseline for future studies of the evolution and molecular epidemiology of this emerging virus in the Americas.

  9. Zika virus in the Americas: Early epidemiological and genetic findings.

    PubMed

    Faria, Nuno Rodrigues; Azevedo, Raimunda do Socorro da Silva; Kraemer, Moritz U G; Souza, Renato; Cunha, Mariana Sequetin; Hill, Sarah C; Thézé, Julien; Bonsall, Michael B; Bowden, Thomas A; Rissanen, Ilona; Rocco, Iray Maria; Nogueira, Juliana Silva; Maeda, Adriana Yurika; Vasami, Fernanda Giseli da Silva; Macedo, Fernando Luiz de Lima; Suzuki, Akemi; Rodrigues, Sueli Guerreiro; Cruz, Ana Cecilia Ribeiro; Nunes, Bruno Tardeli; Medeiros, Daniele Barbosa de Almeida; Rodrigues, Daniela Sueli Guerreiro; Nunes Queiroz, Alice Louize; da Silva, Eliana Vieira Pinto; Henriques, Daniele Freitas; Travassos da Rosa, Elisabeth Salbe; de Oliveira, Consuelo Silva; Martins, Livia Caricio; Vasconcelos, Helena Baldez; Casseb, Livia Medeiros Neves; Simith, Darlene de Brito; Messina, Jane P; Abade, Leandro; Lourenço, José; Carlos Junior Alcantara, Luiz; de Lima, Maricélia Maia; Giovanetti, Marta; Hay, Simon I; de Oliveira, Rodrigo Santos; Lemos, Poliana da Silva; de Oliveira, Layanna Freitas; de Lima, Clayton Pereira Silva; da Silva, Sandro Patroca; de Vasconcelos, Janaina Mota; Franco, Luciano; Cardoso, Jedson Ferreira; Vianez-Júnior, João Lídio da Silva Gonçalves; Mir, Daiana; Bello, Gonzalo; Delatorre, Edson; Khan, Kamran; Creatore, Marisa; Coelho, Giovanini Evelim; de Oliveira, Wanderson Kleber; Tesh, Robert; Pybus, Oliver G; Nunes, Marcio R T; Vasconcelos, Pedro F C

    2016-04-15

    Brazil has experienced an unprecedented epidemic of Zika virus (ZIKV), with ~30,000 cases reported to date. ZIKV was first detected in Brazil in May 2015, and cases of microcephaly potentially associated with ZIKV infection were identified in November 2015. We performed next-generation sequencing to generate seven Brazilian ZIKV genomes sampled from four self-limited cases, one blood donor, one fatal adult case, and one newborn with microcephaly and congenital malformations. Results of phylogenetic and molecular clock analyses show a single introduction of ZIKV into the Americas, which we estimated to have occurred between May and December 2013, more than 12 months before the detection of ZIKV in Brazil. The estimated date of origin coincides with an increase in air passengers to Brazil from ZIKV-endemic areas, as well as with reported outbreaks in the Pacific Islands. ZIKV genomes from Brazil are phylogenetically interspersed with those from other South American and Caribbean countries. Mapping mutations onto existing structural models revealed the context of viral amino acid changes present in the outbreak lineage; however, no shared amino acid changes were found among the three currently available virus genomes from microcephaly cases. Municipality-level incidence data indicate that reports of suspected microcephaly in Brazil best correlate with ZIKV incidence around week 17 of pregnancy, although this correlation does not demonstrate causation. Our genetic description and analysis of ZIKV isolates in Brazil provide a baseline for future studies of the evolution and molecular epidemiology of this emerging virus in the Americas. PMID:27013429

  10. Epidemiological studies of oral cancer.

    PubMed

    Pindborg, J J

    1977-06-01

    The FDI has shown considerable interest in the oral cancer and has in recent years arranged three symposia on the subject. The incidence of oral cancer shows marked geographic differences mostly depending upon environmental factors. In the present paper the epidemiology of oral cancer is illustrated by the relative frequency to total number of cancers and incidence rates from a number of countries. Canada has the highest rate of cancer of the vermilion border, which is extremely rare among dark-skinned people. Even within one country differences may be found, a fact which is illustrated by findings from Czechoslovakia and India. In most of the studies dealing with the etiology of oral cancer tobacco usage in its various forms is shown to be the outstanding factor.

  11. Comparative population genomics of the Borrelia burgdorferi species complex reveals high degree of genetic isolation among species and underscores benefits and constraints to studying intra-specific epidemiological processes.

    PubMed

    Jacquot, Maude; Gonnet, Mathieu; Ferquel, Elisabeth; Abrial, David; Claude, Alexandre; Gasqui, Patrick; Choumet, Valérie; Charras-Garrido, Myriam; Garnier, Martine; Faure, Benjamin; Sertour, Natacha; Dorr, Nelly; De Goër, Jocelyn; Vourc'h, Gwenaël; Bailly, Xavier

    2014-01-01

    Lyme borreliosis, one of the most frequently contracted zoonotic diseases in the Northern Hemisphere, is caused by bacteria belonging to different genetic groups within the Borrelia burgdorferi species complex, which are transmitted by ticks among various wildlife reservoirs, such as small mammals and birds. These features make the Borrelia burgdorferi species complex an attractive biological model that can be used to study the diversification and the epidemiology of endemic bacterial pathogens. We investigated the potential of population genomic approaches to study these processes. Sixty-three strains belonging to three species within the Borrelia burgdorferi complex were isolated from questing ticks in Alsace (France), a region where Lyme disease is highly endemic. We first aimed to characterize the degree of genetic isolation among the species sampled. Phylogenetic and coalescent-based analyses revealed clear delineations: there was a ∼50 fold difference between intra-specific and inter-specific recombination rates. We then investigated whether the population genomic data contained information of epidemiological relevance. In phylogenies inferred using most of the genome, conspecific strains did not cluster in clades. These results raise questions about the relevance of different strategies when investigating pathogen epidemiology. For instance, here, both classical analytic approaches and phylodynamic simulations suggested that population sizes and migration rates were higher in B. garinii populations, which are normally associated with birds, than in B. burgdorferi s.s. populations. The phylogenetic analyses of the infection-related ospC gene and its flanking region provided additional support for this finding. Traces of recombination among the B. burgdorferi s.s. lineages and lineages associated with small mammals were found, suggesting that they shared the same hosts. Altogether, these results provide baseline evidence that can be used to formulate

  12. The use of genetic markers in the molecular epidemiology of histoplasmosis: a systematic review.

    PubMed

    Damasceno, L S; Leitão, T M J S; Taylor, M L; Muniz, M M; Zancopé-Oliveira, R M

    2016-01-01

    Histoplasmosis is a systemic mycosis caused by Histoplasma capsulatum, a dimorphic fungal pathogen that can infect both humans and animals. This disease has worldwide distribution and affects mainly immunocompromised individuals. In the environment, H. capsulatum grows as mold but undergoes a morphologic transition to the yeast morphotype under special conditions. Molecular techniques are important tools to conduct epidemiologic investigations for fungal detection, identification of infection sources, and determination of different fungal genotypes associated to a particular disease symptom. In this study, we performed a systematic review in the PubMed database to improve the understanding about the molecular epidemiology of histoplasmosis. This search was restricted to English and Spanish articles. We included a combination of specific keywords: molecular typing [OR] genetic diversity [OR] polymorphism [AND] H. capsulatum; molecular epidemiology [AND] histoplasmosis; and molecular epidemiology [AND] Histoplasma. In addition, we used the specific terms: histoplasmosis [AND] outbreaks. Non-English or non-Spanish articles, dead links, and duplicate results were excluded from the review. The results reached show that the main methods used for molecular typing of H. capsulatum were: restriction fragment length polymorphism, random amplified polymorphic DNA, microsatellites polymorphism, sequencing of internal transcribed spacers region, and multilocus sequence typing. Different genetic profiles were identified among H. capsulatum isolates, which can be grouped according to their source, geographical origin, and clinical manifestations. PMID:26589702

  13. Integrating the landscape epidemiology and genetics of RNA viruses: rabies in domestic dogs as a model.

    PubMed

    Brunker, K; Hampson, K; Horton, D L; Biek, R

    2012-12-01

    Landscape epidemiology and landscape genetics combine advances in molecular techniques, spatial analyses and epidemiological models to generate a more real-world understanding of infectious disease dynamics and provide powerful new tools for the study of RNA viruses. Using dog rabies as a model we have identified how key questions regarding viral spread and persistence can be addressed using a combination of these techniques. In contrast to wildlife rabies, investigations into the landscape epidemiology of domestic dog rabies requires more detailed assessment of the role of humans in disease spread, including the incorporation of anthropogenic landscape features, human movements and socio-cultural factors into spatial models. In particular, identifying and quantifying the influence of anthropogenic features on pathogen spread and measuring the permeability of dispersal barriers are important considerations for planning control strategies, and may differ according to cultural, social and geographical variation across countries or continents. Challenges for dog rabies research include the development of metapopulation models and transmission networks using genetic information to uncover potential source/sink dynamics and identify the main routes of viral dissemination. Information generated from a landscape genetics approach will facilitate spatially strategic control programmes that accommodate for heterogeneities in the landscape and therefore utilise resources in the most cost-effective way. This can include the efficient placement of vaccine barriers, surveillance points and adaptive management for large-scale control programmes.

  14. Epidemiology, Genetics, and Ecology of Toxigenic Vibrio cholerae

    PubMed Central

    Faruque, Shah M.; Albert, M. John; Mekalanos, John J.

    1998-01-01

    Cholera caused by toxigenic Vibrio cholerae is a major public health problem confronting developing countries, where outbreaks occur in a regular seasonal pattern and are particularly associated with poverty and poor sanitation. The disease is characterized by a devastating watery diarrhea which leads to rapid dehydration, and death occurs in 50 to 70% of untreated patients. Cholera is a waterborne disease, and the importance of water ecology is suggested by the close association of V. cholerae with surface water and the population interacting with the water. Cholera toxin (CT), which is responsible for the profuse diarrhea, is encoded by a lysogenic bacteriophage designated CTXΦ. Although the mechanism by which CT causes diarrhea is known, it is not clear why V. cholerae should infect and elaborate the lethal toxin in the host. Molecular epidemiological surveillance has revealed clonal diversity among toxigenic V. cholerae strains and a continual emergence of new epidemic clones. In view of lysogenic conversion by CTXΦ as a possible mechanism of origination of new toxigenic clones of V. cholerae, it appears that the continual emergence of new toxigenic strains and their selective enrichment during cholera outbreaks constitute an essential component of the natural ecosystem for the evolution of epidemic V. cholerae strains and genetic elements that mediate the transfer of virulence genes. The ecosystem comprising V. cholerae, CTXΦ, the aquatic environment, and the mammalian host offers an understanding of the complex relationship between pathogenesis and the natural selection of a pathogen. PMID:9841673

  15. DNA banking for epidemiologic studies: a review of current practices.

    PubMed

    Steinberg, Karen; Beck, Jeanne; Nickerson, Deborah; Garcia-Closas, Montserrat; Gallagher, Margaret; Caggana, Michele; Reid, Yvonne; Cosentino, Mark; Ji, Jay; Johnson, Delene; Hayes, Richard B; Earley, Marie; Lorey, Fred; Hannon, Harry; Khoury, Muin J; Sampson, Eric

    2002-05-01

    To study genetic risk factors for common diseases, researchers have begun collecting DNA specimens in large epidemiologic studies and surveys. However, little information is available to guide researchers in selecting the most appropriate specimens. In an effort to gather the best information for the selection of specimens for these studies, we convened a meeting of scientists engaged in DNA banking for large epidemiologic studies. In this discussion, we review the information presented at that meeting in the context of recent published information. Factors to be considered in choosing the appropriate specimens for epidemiologic studies include quality and quantity of DNA, convenience of collection and storage, cost, and ability to accommodate future needs for genotyping. We focus on four types of specimens that are stored in these banks: (1) whole blood preserved as dried blood spots; (2) whole blood from which genomic DNA is isolated, (3) immortalized lymphocytes from whole blood or separated lymphocytes, prepared immediately or subsequent to cryopreservation; and (4) buccal epithelial cells. Each of the specimens discussed is useful for epidemiologic studies according to specific needs, which we enumerate in our conclusions.

  16. Genetic Epidemiology and Public Health: The Evolution From Theory to Technology.

    PubMed

    Fallin, M Daniele; Duggal, Priya; Beaty, Terri H

    2016-03-01

    Genetic epidemiology represents a hybrid of epidemiologic designs and statistical models that explicitly consider both genetic and environmental risk factors for disease. It is a relatively new field in public health; the term was first coined only 35 years ago. In this short time, the field has been through a major evolution, changing from a field driven by theory, without the technology for genetic measurement or computational capacity to apply much of the designs and methods developed, to a field driven by rapidly expanding technology in genomic measurement and computational analyses while epidemiologic theory struggles to keep up. In this commentary, we describe 4 different eras of genetic epidemiology, spanning this evolution from theory to technology, what we have learned, what we have added to the broader field of public health, and what remains to be done. PMID:26905340

  17. Genetic Epidemiology and Public Health: The Evolution From Theory to Technology.

    PubMed

    Fallin, M Daniele; Duggal, Priya; Beaty, Terri H

    2016-03-01

    Genetic epidemiology represents a hybrid of epidemiologic designs and statistical models that explicitly consider both genetic and environmental risk factors for disease. It is a relatively new field in public health; the term was first coined only 35 years ago. In this short time, the field has been through a major evolution, changing from a field driven by theory, without the technology for genetic measurement or computational capacity to apply much of the designs and methods developed, to a field driven by rapidly expanding technology in genomic measurement and computational analyses while epidemiologic theory struggles to keep up. In this commentary, we describe 4 different eras of genetic epidemiology, spanning this evolution from theory to technology, what we have learned, what we have added to the broader field of public health, and what remains to be done.

  18. An overview of the epidemiology and genetics of acromegaly.

    PubMed

    Daly, A F; Petrossians, P; Beckers, A

    2005-01-01

    Historical data indicate that pituitary tumors represent 10% of intracranial tumors, while adenomas are noted in approximately 14-23% of normal subjects on autopsy or magnetic resonance imaging (MRI). About 2.5% of these tumors stain positive for GH in histopathologic studies. In contrast, the prevalence of clinically diagnosed acromegaly is lower at 36-69 per million population. Ongoing studies indicate that the actual prevalence of acromegaly in the community may be higher than previous epidemiologic data suggest. Acromegaly can occur both sporadically and in the setting of familial conditions, such as multiple endocrine neoplasia type 1 (MEN1) and Carney complex (CNC). Isolated familial somatotropinoma has been described and newer data suggest that acromegaly may also occur in non-MEN1/CNC families in combination with other pituitary tumor phenotypes.

  19. AN EPIDEMIOLOGICAL STUDY OF ALCOHOLISM

    PubMed Central

    Ponnudrai, R.; Jayakar, J.; Raju, B.; Pattamuthu, R.

    1991-01-01

    SUMMARY The study was aimed to assess the prevalence of alcoholism in Madras City. A locality in North Madras was chosen and the houses were selected at random. The family members in these houses were assessed using the Michigan Alcoholism Screening test. 222 persons were thus studied. 16.67 of the males were found to be suffering from alcoholism. PMID:21927497

  20. Transcriptomic Identification of ADH1B as a Novel Candidate Gene for Obesity and Insulin Resistance in Human Adipose Tissue in Mexican Americans from the Veterans Administration Genetic Epidemiology Study (VAGES)

    PubMed Central

    Winnier, Deidre A.; Fourcaudot, Marcel; Norton, Luke; Abdul-Ghani, Muhammad A.; Hu, Shirley L.; Farook, Vidya S.; Coletta, Dawn K.; Kumar, Satish; Puppala, Sobha; Chittoor, Geetha; Dyer, Thomas D.; Arya, Rector; Carless, Melanie; Lehman, Donna M.; Curran, Joanne E.; Cromack, Douglas T.; Tripathy, Devjit; Blangero, John; Duggirala, Ravindranath; Göring, Harald H. H.; DeFronzo, Ralph A.; Jenkinson, Christopher P.

    2015-01-01

    Type 2 diabetes (T2D) is a complex metabolic disease that is more prevalent in ethnic groups such as Mexican Americans, and is strongly associated with the risk factors obesity and insulin resistance. The goal of this study was to perform whole genome gene expression profiling in adipose tissue to detect common patterns of gene regulation associated with obesity and insulin resistance. We used phenotypic and genotypic data from 308 Mexican American participants from the Veterans Administration Genetic Epidemiology Study (VAGES). Basal fasting RNA was extracted from adipose tissue biopsies from a subset of 75 unrelated individuals, and gene expression data generated on the Illumina BeadArray platform. The number of gene probes with significant expression above baseline was approximately 31,000. We performed multiple regression analysis of all probes with 15 metabolic traits. Adipose tissue had 3,012 genes significantly associated with the traits of interest (false discovery rate, FDR ≤ 0.05). The significance of gene expression changes was used to select 52 genes with significant (FDR ≤ 10-4) gene expression changes across multiple traits. Gene sets/Pathways analysis identified one gene, alcohol dehydrogenase 1B (ADH1B) that was significantly enriched (P < 10-60) as a prime candidate for involvement in multiple relevant metabolic pathways. Illumina BeadChip derived ADH1B expression data was consistent with quantitative real time PCR data. We observed significant inverse correlations with waist circumference (2.8 x 10-9), BMI (5.4 x 10-6), and fasting plasma insulin (P < 0.001). These findings are consistent with a central role for ADH1B in obesity and insulin resistance and provide evidence for a novel genetic regulatory mechanism for human metabolic diseases related to these traits. PMID:25830378

  1. Methodological considerations in the study of genetic discrimination.

    PubMed

    Treloar, Susan; Taylor, Sandra; Otlowski, Margaret; Barlow-Stewart, Kristine; Stranger, Mark; Chenoweth, Kellie

    2004-01-01

    The potential significance and dimensions of genetic discrimination have been described extensively in published literature, but epidemiological and verified case data are limited. Obtaining unbiased data from individuals about discrimination which has been based on erroneous or unjustifiable assumptions about their genetic predispositions poses unique challenges. Through review and discussion of research literature, we identify methodological considerations for collecting valid epidemiological data on genetic discrimination from individuals in the community; in particular, we consider issues which relate to sampling, selection and response. We identify issues to promote sound study design, with particular attention to verification of genetic discrimination, and highlight the importance of clinical and genetic knowledge of complex genotype-phenotype relationships.

  2. Genetic-epidemiological evidence for the role of acetaldehyde in cancers related to alcohol drinking.

    PubMed

    Eriksson, C J Peter

    2015-01-01

    Alcohol drinking increases the risk for a number of cancers. Currently, the highest risk (Group 1) concerns oral cavity, pharynx, larynx, esophagus, liver, colorectum, and female breast, as assessed by the International Agency for Research on Cancer (IARC). Alcohol and other beverage constituents, their metabolic effects, and alcohol-related unhealthy lifestyles have been suggested as etiological factors. The aim of the present survey is to evaluate the carcinogenic role of acetaldehyde in alcohol-related cancers, with special emphasis on the genetic-epidemiological evidence. Acetaldehyde, as a constituent of alcoholic beverages, and microbial and endogenous alcohol oxidation well explain why alcohol-related cancers primarily occur in the digestive tracts and other tissues with active alcohol and acetaldehyde metabolism. Genetic-epidemiological research has brought compelling evidence for the causality of acetaldehyde in alcohol-related cancers. Thus, IARC recently categorized alcohol-drinking-related acetaldehyde to Group 1 for head and neck and esophageal cancers. This is probably just the tip of the iceberg, since more recent epidemiological studies have also shown significant positive associations between the aldehyde dehydrogenase ALDH2 (rs671)*2 allele (encoding inactive enzyme causing high acetaldehyde elevations) and gastric, colorectal, lung, and hepatocellular cancers. However, a number of the current studies lack the appropriate matching or stratification of alcohol drinking in the case-control comparisons, which has led to erroneous interpretations of the data. Future studies should consider these aspects more thoroughly. The polymorphism phenotypes (flushing and nausea) may provide valuable tools for future successful health education in the prevention of alcohol-drinking-related cancers.

  3. Assigning the source of human campylobacteriosis in New Zealand: a comparative genetic and epidemiological approach.

    PubMed

    Mullner, Petra; Spencer, Simon E F; Wilson, Daniel J; Jones, Geoff; Noble, Alasdair D; Midwinter, Anne C; Collins-Emerson, Julie M; Carter, Philip; Hathaway, Steve; French, Nigel P

    2009-12-01

    Integrated surveillance of infectious multi-source diseases using a combination of epidemiology, ecology, genetics and evolution can provide a valuable risk-based approach for the control of important human pathogens. This includes a better understanding of transmission routes and the impact of human activities on the emergence of zoonoses. Until recently New Zealand had extraordinarily high and increasing rates of notified human campylobacteriosis, and our limited understanding of the source of these infections was hindering efforts to control this disease. Genetic and epidemiological modeling of a 3-year dataset comprising multilocus sequence typed isolates from human clinical cases, coupled with concurrent data on food and environmental sources, enabled us to estimate the relative importance of different sources of human disease. Our studies provided evidence that poultry was the leading cause of human campylobacteriosis in New Zealand, causing an estimated 58-76% of cases with widely varying contributions by individual poultry suppliers. These findings influenced national policy and, after the implementation of poultry industry-specific interventions, a dramatic decline in human notified cases was observed in 2008. The comparative-modeling and molecular sentinel surveillance approach proposed in this study provides new opportunities for the management of zoonotic diseases. PMID:19778636

  4. Tumours of the lacrimal gland. Epidemiological, clinical and genetic characteristics.

    PubMed

    von Holstein, Sarah Linéa

    2013-11-01

    Tumours of the lacrimal gland are rare, but the prognosis may be grave. To date, no population-based incidence and distribution data on lacrimal gland tumours exist. In addition, almost nothing is known about the genetic profile of epithelial tumours of the lacrimal gland. We collected specimens and clinical files on all biopsied lacrimal gland lesions in Denmark over a 34-year period and re-evaluated the diagnosis to provide updated population-based incidence rates and epidemiological characteristics. Clinical data regarding symptoms, clinical examinations, treatment and follow-up were collected for patients with adenoid cystic carcinoma (ACC), pleomorphic adenoma (PA), carcinoma ex pleomorphic adenoma (Ca-ex-PA) and mucoepidermoid carcinoma (MEC). Using RT-PCR, FISH, immunohistochemistry, Q-PCR and high-resolution array-based comparative genomic hybridization (arrayCGH) we explored the genetic characteristics including copy number alterations (CNA) in ACC, PA, Ca-ex-PA and MEC. The incidence of biopsied lacrimal gland lesions was 1.3/1,000,000/year, and ~50% were neoplastic lesions. Of these, 55% were malignant tumours with epithelial tumours as the most frequent. The overall incidence was increasing, and this was caused by an increase in biopsied non-neoplastic lesions. We found that 10/14 ACCs either expressed the MYB-NFIB fusion gene and/or had rearrangements of MYB. All ACCs expressed the MYB protein. ACC was characterized by recurrent copy number losses involving 6q, 12q and 17q and gains involving 19q, 8q and 11q. ArrayCGH revealed an apparently normal genomic profile in 11/19 PAs. The remaining 8 PAs had recurrent copy number losses involving 1p, 6q, 8q and 13q and gain involving 9p. PA expressed PLAG1 in all tumours whereas only 2/29 tumours expressed HMGA2. Ca-ex-PA was characterized by recurrent copy number gain involving 22q. PLAG1 was expressed in 3/5 Ca-ex-PA whereas none of these tumours expressed HMGA2. MEC expressed the CRTC1-MAML2, and this

  5. Examination of Different Exposure Metrics in an Epidemiological Study

    EPA Science Inventory

    Epidemiological studies of air pollution have traditionally relied upon measurements of ambient concentration from central-site monitoring stations as surrogates of population exposures. However, depending on the epidemiological study design, this approach may introduce exposure...

  6. Blastocystis: Genetic diversity and molecular methods for diagnosis and epidemiology.

    PubMed

    Stensvold, Christen Rune

    2013-01-01

    Blastocystis, an unusual anaerobic, single-celled stramenopile, is a remarkably successful intestinal parasite of a vast array of host species including humans. Fecal Deoxyribonucleic acid (DNA) analysis by nucleic-acid based methods in particular has led to significant advances in Blastocystis diagnostics and research over the past few years enabling accurate identification of carriers and molecular characterization by high discriminatory power. Moreover, Blastocystis comprises a multitude of subtypes (STs) (arguably species) many of which have been identified only recently and molecular epidemiological studies have revealed a significant difference in the distribution of STs across host species and geographical regions. Having a cosmopolitan distribution, the parasite is a common laboratory finding in the stools of individuals with and without intestinal symptoms across the entire globe and while the parasite remains extremely difficult to eradicate and isolate in culture, appropriate molecular tools are now available to resolve important questions such as whether the clinical outcome of colonization is linked to ST and whether Blastocystis is transmitted zoonotically. This review summarizes some of the recent advances in the molecular diagnosis of Blastocystis and gives an introduction to Blastocystis STs, including a recommendation of subtyping methodology based on recent data and method comparisons. A few suggestions for future directions and research areas are given in the light of relevant technological advances and the availability of mitochondrial and nuclear genomes.

  7. Epidemiological studies of cancer in aircrew.

    PubMed

    Hammer, Gaël P; Blettner, Maria; Zeeb, Hajo

    2009-10-01

    Exposure to cosmic ionising radiation, in addition to other specific occupational risks, is of concern to aircrew members. Epidemiological studies provide an objective way to assess the health of this occupational group. We systematically reviewed the epidemiological literature on health of aircrew members since 1990, focusing on cancer as the endpoint of interest. Sixty-five relevant publications were identified and reviewed. Whereas overall cancer incidence and mortality was generally lower than in the comparison population, consistently elevated risks were reported for breast cancer incidence in female aircrew members and for melanoma in both male and female aircrew members. Brain cancer was increased in some studies among pilots. Occasionally trends of increasing cancer mortality or incidence with increasing estimated radiation dose were reported. Ionising radiation is considered to contribute little if at all to the elevated risks for cancers among aircrew, whereas excess ultraviolet radiation is a probable cause of the increased melanoma risk. PMID:19608578

  8. Characterizing Race/Ethnicity and Genetic Ancestry for 100,000 Subjects in the Genetic Epidemiology Research on Adult Health and Aging (GERA) Cohort.

    PubMed

    Banda, Yambazi; Kvale, Mark N; Hoffmann, Thomas J; Hesselson, Stephanie E; Ranatunga, Dilrini; Tang, Hua; Sabatti, Chiara; Croen, Lisa A; Dispensa, Brad P; Henderson, Mary; Iribarren, Carlos; Jorgenson, Eric; Kushi, Lawrence H; Ludwig, Dana; Olberg, Diane; Quesenberry, Charles P; Rowell, Sarah; Sadler, Marianne; Sakoda, Lori C; Sciortino, Stanley; Shen, Ling; Smethurst, David; Somkin, Carol P; Van Den Eeden, Stephen K; Walter, Lawrence; Whitmer, Rachel A; Kwok, Pui-Yan; Schaefer, Catherine; Risch, Neil

    2015-08-01

    Using genome-wide genotypes, we characterized the genetic structure of 103,006 participants in the Kaiser Permanente Northern California multi-ethnic Genetic Epidemiology Research on Adult Health and Aging Cohort and analyzed the relationship to self-reported race/ethnicity. Participants endorsed any of 23 race/ethnicity/nationality categories, which were collapsed into seven major race/ethnicity groups. By self-report the cohort is 80.8% white and 19.2% minority; 93.8% endorsed a single race/ethnicity group, while 6.2% endorsed two or more. Principal component (PC) and admixture analyses were generally consistent with prior studies. Approximately 17% of subjects had genetic ancestry from more than one continent, and 12% were genetically admixed, considering only nonadjacent geographical origins. Self-reported whites were spread on a continuum along the first two PCs, indicating extensive mixing among European nationalities. Self-identified East Asian nationalities correlated with genetic clustering, consistent with extensive endogamy. Individuals of mixed East Asian-European genetic ancestry were easily identified; we also observed a modest amount of European genetic ancestry in individuals self-identified as Filipinos. Self-reported African Americans and Latinos showed extensive European and African genetic ancestry, and Native American genetic ancestry for the latter. Among 3741 genetically identified parent-child pairs, 93% were concordant for self-reported race/ethnicity; among 2018 genetically identified full-sib pairs, 96% were concordant; the lower rate for parent-child pairs was largely due to intermarriage. The parent-child pairs revealed a trend toward increasing exogamy over time; the presence in the cohort of individuals endorsing multiple race/ethnicity categories creates interesting challenges and future opportunities for genetic epidemiologic studies. PMID:26092716

  9. Characterizing Race/Ethnicity and Genetic Ancestry for 100,000 Subjects in the Genetic Epidemiology Research on Adult Health and Aging (GERA) Cohort

    PubMed Central

    Banda, Yambazi; Kvale, Mark N.; Hoffmann, Thomas J.; Hesselson, Stephanie E.; Ranatunga, Dilrini; Tang, Hua; Sabatti, Chiara; Croen, Lisa A.; Dispensa, Brad P.; Henderson, Mary; Iribarren, Carlos; Jorgenson, Eric; Kushi, Lawrence H.; Ludwig, Dana; Olberg, Diane; Quesenberry, Charles P.; Rowell, Sarah; Sadler, Marianne; Sakoda, Lori C.; Sciortino, Stanley; Shen, Ling; Smethurst, David; Somkin, Carol P.; Van Den Eeden, Stephen K.; Walter, Lawrence; Whitmer, Rachel A.; Kwok, Pui-Yan; Schaefer, Catherine; Risch, Neil

    2015-01-01

    Using genome-wide genotypes, we characterized the genetic structure of 103,006 participants in the Kaiser Permanente Northern California multi-ethnic Genetic Epidemiology Research on Adult Health and Aging Cohort and analyzed the relationship to self-reported race/ethnicity. Participants endorsed any of 23 race/ethnicity/nationality categories, which were collapsed into seven major race/ethnicity groups. By self-report the cohort is 80.8% white and 19.2% minority; 93.8% endorsed a single race/ethnicity group, while 6.2% endorsed two or more. Principal component (PC) and admixture analyses were generally consistent with prior studies. Approximately 17% of subjects had genetic ancestry from more than one continent, and 12% were genetically admixed, considering only nonadjacent geographical origins. Self-reported whites were spread on a continuum along the first two PCs, indicating extensive mixing among European nationalities. Self-identified East Asian nationalities correlated with genetic clustering, consistent with extensive endogamy. Individuals of mixed East Asian–European genetic ancestry were easily identified; we also observed a modest amount of European genetic ancestry in individuals self-identified as Filipinos. Self-reported African Americans and Latinos showed extensive European and African genetic ancestry, and Native American genetic ancestry for the latter. Among 3741 genetically identified parent–child pairs, 93% were concordant for self-reported race/ethnicity; among 2018 genetically identified full-sib pairs, 96% were concordant; the lower rate for parent–child pairs was largely due to intermarriage. The parent–child pairs revealed a trend toward increasing exogamy over time; the presence in the cohort of individuals endorsing multiple race/ethnicity categories creates interesting challenges and future opportunities for genetic epidemiologic studies. PMID:26092716

  10. ADHD in the Arab World: A Review of Epidemiologic Studies

    ERIC Educational Resources Information Center

    Farah, Lynn G.; Fayyad, John A.; Eapen, Valsamma; Cassir,Youmna; Salamoun, Mariana M.; Tabet, Caroline C.; Mneimneh, Zeina N.; Karam, Elie G.

    2009-01-01

    Objective: Epidemiological studies on psychiatric disorders are quite rare in the Arab World. This article reviews epidemiological studies on ADHD in all the Arab countries. Method: All epidemiological studies on ADHD conducted from 1966 through th present were reviewed. Samples were drawn from the general community, primary care clinical…

  11. Epidemiologic studies based on the Chernobyl accident

    SciTech Connect

    Beebe, G.

    1996-12-31

    There are great opportunities in the post-Chernobyl experience for significant epidemiologic research, perhaps even more in the area of disaster research than in the area of the human health effects of ionizing radiation. But the potential opportunity for learning the effects of radioiodine on the thyroid is very great and has aroused widespread national and international investigative interest. The opportunities for significant epidemiologic research are, however, severely limited currently by the worsening economic situation in Belarus and Ukraine, where the greatest exposure occurred, and by the lack of personnel trained in appropriate methods of study, the lack of modern equipment, the lack of supplies, the poor communication facilities, and the difficulties of accurate dose estimation. the disadvantages may or may not outweigh the obvious advantages of large numbers, the extensive direct thyroidal measurements made shortly after the accident in 1986, the magnitude of the releases of radioiodine, and the retention of the former Soviet system of universal medical care. Both the European Commission (EC) and the World Health Organization (WHO) have been working actively to strengthen the infrastructure of Russia, Belarus, and Ukraine. New scientific knowledge has yet to emerge from the extensive epidemiologic work but information of considerable public health significance has begun to accumulate. The bulk of the thyroid cancer has been shown to be valid by international pathology review; both EC and WHO representatives have declared the increase in thyroid cancer among children to have been caused in large part by Chernobyl. No increase in leukemia has been seen in the general population. The WHO pilot studies have shown no evidence of an increase in psychologic or neurologic complications among those exposed in utero. Ongoing epidemiologic work can be described by review of the inventory that the WHO has begun to maintain and publish. 20 refs., 7 tabs.

  12. A genetic epidemiology approach to cyber-security.

    PubMed

    Gil, Santiago; Kott, Alexander; Barabási, Albert-László

    2014-01-01

    While much attention has been paid to the vulnerability of computer networks to node and link failure, there is limited systematic understanding of the factors that determine the likelihood that a node (computer) is compromised. We therefore collect threat log data in a university network to study the patterns of threat activity for individual hosts. We relate this information to the properties of each host as observed through network-wide scans, establishing associations between the network services a host is running and the kinds of threats to which it is susceptible. We propose a methodology to associate services to threats inspired by the tools used in genetics to identify statistical associations between mutations and diseases. The proposed approach allows us to determine probabilities of infection directly from observation, offering an automated high-throughput strategy to develop comprehensive metrics for cyber-security. PMID:25028059

  13. A genetic epidemiology approach to cyber-security

    PubMed Central

    Gil, Santiago; Kott, Alexander; Barabási, Albert-László

    2014-01-01

    While much attention has been paid to the vulnerability of computer networks to node and link failure, there is limited systematic understanding of the factors that determine the likelihood that a node (computer) is compromised. We therefore collect threat log data in a university network to study the patterns of threat activity for individual hosts. We relate this information to the properties of each host as observed through network-wide scans, establishing associations between the network services a host is running and the kinds of threats to which it is susceptible. We propose a methodology to associate services to threats inspired by the tools used in genetics to identify statistical associations between mutations and diseases. The proposed approach allows us to determine probabilities of infection directly from observation, offering an automated high-throughput strategy to develop comprehensive metrics for cyber-security. PMID:25028059

  14. A genetic epidemiology approach to cyber-security.

    PubMed

    Gil, Santiago; Kott, Alexander; Barabási, Albert-László

    2014-07-16

    While much attention has been paid to the vulnerability of computer networks to node and link failure, there is limited systematic understanding of the factors that determine the likelihood that a node (computer) is compromised. We therefore collect threat log data in a university network to study the patterns of threat activity for individual hosts. We relate this information to the properties of each host as observed through network-wide scans, establishing associations between the network services a host is running and the kinds of threats to which it is susceptible. We propose a methodology to associate services to threats inspired by the tools used in genetics to identify statistical associations between mutations and diseases. The proposed approach allows us to determine probabilities of infection directly from observation, offering an automated high-throughput strategy to develop comprehensive metrics for cyber-security.

  15. Genetic diversity and epidemiology of infectious hematopoietic necrosis virus in Alaska

    USGS Publications Warehouse

    Emmenegger, E.G; Meyers, T.R.; Burton, T.O.; Kurath, G.

    2000-01-01

    Forty-two infectious hematopoietic necrosis virus (IHNV) isolates from Alaska were analyzed using the ribonuclease protection assay (RPA) and nucleotide sequencing. RPA analyses, utilizing 4 probes, N5, N3 (N gene), GF (G gene), and NV (NV gene), determined that the haplotypes of all 3 genes demonstrated a consistent spatial pattern. Virus isolates belonging to the most common haplotype groups were distributed throughout Alaska, whereas isolates in small haplotype groups were obtained from only 1 site (hatchery, lake, etc.). The temporal pattern of the GF haplotypes suggested a 'genetic acclimation' of the G gene, possibly due to positive selection on the glycoprotein. A pairwise comparison of the sequence data determined that the maximum nucleotide diversity of the isolates was 2.75% (10 mismatches) for the NV gene, and 1.99% (6 mismatches) for a 301 base pair region of the G gene, indicating that the genetic diversity of IHNV within Alaska is notably lower than in the more southern portions of the IHNV North American range. Phylogenetic analysis of representative Alaskan sequences and sequences of 12 previously characterized IHNV strains from Washington, Oregon, Idaho, California (USA) and British Columbia (Canada) distinguished the isolates into clusters that correlated with geographic origin and indicated that the Alaskan and British Columbia isolates may have a common viral ancestral lineage. Comparisons of multiple isolates from the same site provided epidemiological insights into viral transmission patterns and indicated that viral evolution, viral introduction, and genetic stasis were the mechanisms involved with IHN virus population dynamics in Alaska. The examples of genetic stasis and the overall low sequence heterogeneity of the Alaskan isolates suggested that they are evolutionarily constrained. This study establishes a baseline of genetic fingerprint patterns and sequence groups representing the genetic diversity of Alaskan IHNV isolates. This

  16. Epidemiology and genetic diversity of Taenia asiatica: a systematic review

    PubMed Central

    2014-01-01

    Taenia asiatica has made a remarkable journey through the scientific literature of the past 50 years, starting with the paradoxical observation of high prevalences of T. saginata-like tapeworms in non-beef consuming populations, to the full description of its mitochondrial genome. Experimental studies conducted in the 1980s and 1990s have made it clear that the life cycle of T. asiatica is comparable to that of T. saginata, except for pigs being the preferential intermediate host and liver the preferential location of the cysts. Whether or not T. asiatica can cause human cysticercosis, as is the case for Taenia solium, remains unclear. Given the specific conditions needed to complete its life cycle, in particular the consumption of raw or poorly cooked pig liver, the transmission of T. asiatica shows an important ethno-geographical association. So far, T. asiatica has been identified in Taiwan, South Korea, Indonesia, the Philippines, Thailand, south-central China, Vietnam, Japan and Nepal. Especially this last observation indicates that its distribution is not restricted to South-East-Asia, as was thought so far. Indeed, the molecular tools developed over the last 20 years have made it increasingly possible to differentiate T. asiatica from other taeniids. Such tools also indicated that T. asiatica is related more closely to T. saginata than to T. solium, feeding the debate on its taxonomic status as a separate species versus a subspecies of T. saginata. Furthermore, the genetic diversity within T. asiatica appears to be very minimal, indicating that this parasite may be on the verge of extinction. However, recent studies have identified potential hybrids between T. asiatica and T. saginata, reopening the debate on the genetic diversity of T. asiatica and its status as a separate species. PMID:24450957

  17. Epidemiology and genetic diversity of Taenia asiatica: a systematic review.

    PubMed

    Ale, Anita; Victor, Bjorn; Praet, Nicolas; Gabriël, Sarah; Speybroeck, Niko; Dorny, Pierre; Devleesschauwer, Brecht

    2014-01-01

    Taenia asiatica has made a remarkable journey through the scientific literature of the past 50 years, starting with the paradoxical observation of high prevalences of T. saginata-like tapeworms in non-beef consuming populations, to the full description of its mitochondrial genome. Experimental studies conducted in the 1980s and 1990s have made it clear that the life cycle of T. asiatica is comparable to that of T. saginata, except for pigs being the preferential intermediate host and liver the preferential location of the cysts. Whether or not T. asiatica can cause human cysticercosis, as is the case for Taenia solium, remains unclear. Given the specific conditions needed to complete its life cycle, in particular the consumption of raw or poorly cooked pig liver, the transmission of T. asiatica shows an important ethno-geographical association. So far, T. asiatica has been identified in Taiwan, South Korea, Indonesia, the Philippines, Thailand, south-central China, Vietnam, Japan and Nepal. Especially this last observation indicates that its distribution is not restricted to South-East-Asia, as was thought so far. Indeed, the molecular tools developed over the last 20 years have made it increasingly possible to differentiate T. asiatica from other taeniids. Such tools also indicated that T. asiatica is related more closely to T. saginata than to T. solium, feeding the debate on its taxonomic status as a separate species versus a subspecies of T. saginata. Furthermore, the genetic diversity within T. asiatica appears to be very minimal, indicating that this parasite may be on the verge of extinction. However, recent studies have identified potential hybrids between T. asiatica and T. saginata, reopening the debate on the genetic diversity of T. asiatica and its status as a separate species. PMID:24450957

  18. Genetic characterisation and molecular epidemiology of Ascaris spp. from humans and pigs in Brazil.

    PubMed

    Iñiguez, Alena M; Leles, Daniela; Jaeger, Lauren H; Carvalho-Costa, Filipe A; Araújo, Adauto

    2012-10-01

    The molecular epidemiology of Ascaris spp. of human and pig origin has been studied as a means to assess the potential of pigs as reservoirs for human ascariasis. In this study, human (H) and pig (P) Ascaris spp. haplotypes from two Brazilian regions were characterised based on two mitochondrial genes, nad1 and cox1. The results show six haplotypes of the cox1 gene, with two haplotypes (H9P9 and P3) corresponding to haplotypes previously characterised in China. Because P3 was found in humans in this study, it was designated as H14P3. Furthermore, five new Ascaris spp. nad1 haplotypes from humans (H12-H16) and five from pigs (P16-P20) were observed, with one being highly frequent and present in both hosts, here designated as H12P17. Phylogenetic and network analysis demonstrated that the molecular epidemiology of Ascaris spp. in Brazil is driven by the globally distributed haplotypes cox1 H14P3 and nad1 H12P17. In conclusion, in this study genetic characterisation of Ascaris spp. showed that humans and pigs share common haplotypes that are also present in two widely separated geographical regions of Brazil. PMID:22944771

  19. Genetic characterisation and molecular epidemiology of Ascaris spp. from humans and pigs in Brazil.

    PubMed

    Iñiguez, Alena M; Leles, Daniela; Jaeger, Lauren H; Carvalho-Costa, Filipe A; Araújo, Adauto

    2012-10-01

    The molecular epidemiology of Ascaris spp. of human and pig origin has been studied as a means to assess the potential of pigs as reservoirs for human ascariasis. In this study, human (H) and pig (P) Ascaris spp. haplotypes from two Brazilian regions were characterised based on two mitochondrial genes, nad1 and cox1. The results show six haplotypes of the cox1 gene, with two haplotypes (H9P9 and P3) corresponding to haplotypes previously characterised in China. Because P3 was found in humans in this study, it was designated as H14P3. Furthermore, five new Ascaris spp. nad1 haplotypes from humans (H12-H16) and five from pigs (P16-P20) were observed, with one being highly frequent and present in both hosts, here designated as H12P17. Phylogenetic and network analysis demonstrated that the molecular epidemiology of Ascaris spp. in Brazil is driven by the globally distributed haplotypes cox1 H14P3 and nad1 H12P17. In conclusion, in this study genetic characterisation of Ascaris spp. showed that humans and pigs share common haplotypes that are also present in two widely separated geographical regions of Brazil.

  20. Molecular markers for the study of streptococcal epidemiology.

    PubMed

    McMillan, David J; Sanderson-Smith, Martina L; Smeesters, Pierre Robert; Sriprakash, Kadaba S

    2013-01-01

    Diseases caused by Streptococcus pyogenes (Group A streptococcus, GAS) range from superficial infections such as pharyngitis and impetigo to potentially fatal rheumatic heart disease and invasive disease. Studies spanning emm-typing surveillance to population genomics are providing new insights into the epidemiology, pathogenesis, and biology of this organism. Such studies have demonstrated the differences that exist in the epidemiology of streptococcal disease between developing and developed nations. In developing nations, where streptococcal disease is endemic, the diversity of GAS emm-types circulating is much greater than that found in developed nations. An association between emm-type and disease, as observed in developed countries is also lacking. Intriguingly, comparative genetic studies suggest that emm-type is not always a good predictor of the evolutionary relatedness of geographically distant isolates. A view of GAS as a highly dynamic organism, in possession of a core set of virulence genes that contribute to host niche specialization and common pathogenic processes, augmented by accessory genes that change the relative virulence of specific lineages is emerging. Our inability to definitively identify genetic factors that contribute to specific disease outcome underscores the complex nature of streptococcal diseases. PMID:23179674

  1. Genetic Epidemiology of Type 1 Diabetes in the 22 Arab Countries.

    PubMed

    Zayed, Hatem

    2016-05-01

    Type 1 diabetes (T1D) is a complex autoimmune disorder that results from the T cell-mediated destruction of the pancreatic β cells and is due to interactions between environmental and genetic factors. Although Arabs have one of the highest global incidence and prevalence rates of T1D, unfortunately, there is a dearth of information regarding the genetic epidemiology of T1D in the Arab world. Arabs share several HLA haplotypes with other ethnic groups, which confer either susceptibility or protection to T1D, but they have specific haplotypes that are distinctive from other ethnicities. Among different Arab countries, several non-HLA genes were reported to be associated with susceptibility to T1D, including CTLA4, CD28, PTPN22, TCRβ, CD3z, IL15, BANK1, and ZAP70. In Arab countries, consanguinity, endogamy, and first-cousin marriage rates are some of the highest reported worldwide and are responsible for the creation of several inbreeding communities within the Arab world that have led to an increase in homozygosity of both the HLA haplotypes and non-HLA genes associated with either protection or susceptibility to T1D among Arabs. Homozygosity reduces the HLA complexity and is expected to facilitate our understanding of the mode of inheritance of HLA haplotypes and provide valuable insight into the intricate genotype-phenotype correlations in T1D patients. In this review, based on literature studies, I will discuss the current epidemiological profile and molecular genetic risks of Arabs with T1D. PMID:26983625

  2. Genetic Epidemiology of Type 1 Diabetes in the 22 Arab Countries.

    PubMed

    Zayed, Hatem

    2016-05-01

    Type 1 diabetes (T1D) is a complex autoimmune disorder that results from the T cell-mediated destruction of the pancreatic β cells and is due to interactions between environmental and genetic factors. Although Arabs have one of the highest global incidence and prevalence rates of T1D, unfortunately, there is a dearth of information regarding the genetic epidemiology of T1D in the Arab world. Arabs share several HLA haplotypes with other ethnic groups, which confer either susceptibility or protection to T1D, but they have specific haplotypes that are distinctive from other ethnicities. Among different Arab countries, several non-HLA genes were reported to be associated with susceptibility to T1D, including CTLA4, CD28, PTPN22, TCRβ, CD3z, IL15, BANK1, and ZAP70. In Arab countries, consanguinity, endogamy, and first-cousin marriage rates are some of the highest reported worldwide and are responsible for the creation of several inbreeding communities within the Arab world that have led to an increase in homozygosity of both the HLA haplotypes and non-HLA genes associated with either protection or susceptibility to T1D among Arabs. Homozygosity reduces the HLA complexity and is expected to facilitate our understanding of the mode of inheritance of HLA haplotypes and provide valuable insight into the intricate genotype-phenotype correlations in T1D patients. In this review, based on literature studies, I will discuss the current epidemiological profile and molecular genetic risks of Arabs with T1D.

  3. Genetic epidemiology of visceral leishmaniasis in northeastern Brazil.

    PubMed

    Peacock, C S; Collins, A; Shaw, M A; Silveira, F; Costa, J; Coste, C H; Nascimento, M D; Siddiqui, R; Shaw, J J; Blackwell, J M

    2001-04-01

    Familial clustering of disease, racial differences in asymptomatic:disease ratios, and studies of mice all point to a genetic component for disease susceptibility in visceral leishmaniasis. Analysis of 87 multi-case pedigrees (824 individuals; 138 nuclear families) from a region of northeastern Brazil endemic for Leishmania chagasi demonstrates a high relative risk ratio (lambda(2S) = 34) to further siblings of affected sibling pairs. Complex segregation analysis using POINTER and COMDS show that all single locus models, as well as polygenic and multifactorial models, provide a significantly (P < 0.001) better fit to the data than a sporadic model. Of the genetic models, the general single locus model was not significantly different from additive or dominant single locus models, all of which gave a gene frequency for the putative disease susceptibility allele of approximately 0.002. The general single locus model was strongly favored (P < 0.001) over a recessive single gene model. Using POINTER, polygenic and multifactorial models were clearly rejected (P < 0.001 in all cases) in favor of the general single locus model. Using COMDS, the analysis was extended to consider two locus models. Results under a general two-locus model did not differ significantly from the dominant, additive, or general single locus models. Under this model, one locus was estimated at a gene frequency of 0.0017, i.e., in the same range as the disease susceptibility locus for the most favored single gene models, with the second locus at a much lower frequency of 0.0002. Hence, the data support the hypothesis that a single major gene may be important in determining disease susceptibility in this population. To identify the gene(s) involved, a genome scan with replication using two subsets of these larger pedigrees with power to detect linkage is in progress. PMID:11255246

  4. Genetic epidemiology of visceral leishmaniasis in northeastern Brazil.

    PubMed

    Peacock, C S; Collins, A; Shaw, M A; Silveira, F; Costa, J; Coste, C H; Nascimento, M D; Siddiqui, R; Shaw, J J; Blackwell, J M

    2001-04-01

    Familial clustering of disease, racial differences in asymptomatic:disease ratios, and studies of mice all point to a genetic component for disease susceptibility in visceral leishmaniasis. Analysis of 87 multi-case pedigrees (824 individuals; 138 nuclear families) from a region of northeastern Brazil endemic for Leishmania chagasi demonstrates a high relative risk ratio (lambda(2S) = 34) to further siblings of affected sibling pairs. Complex segregation analysis using POINTER and COMDS show that all single locus models, as well as polygenic and multifactorial models, provide a significantly (P < 0.001) better fit to the data than a sporadic model. Of the genetic models, the general single locus model was not significantly different from additive or dominant single locus models, all of which gave a gene frequency for the putative disease susceptibility allele of approximately 0.002. The general single locus model was strongly favored (P < 0.001) over a recessive single gene model. Using POINTER, polygenic and multifactorial models were clearly rejected (P < 0.001 in all cases) in favor of the general single locus model. Using COMDS, the analysis was extended to consider two locus models. Results under a general two-locus model did not differ significantly from the dominant, additive, or general single locus models. Under this model, one locus was estimated at a gene frequency of 0.0017, i.e., in the same range as the disease susceptibility locus for the most favored single gene models, with the second locus at a much lower frequency of 0.0002. Hence, the data support the hypothesis that a single major gene may be important in determining disease susceptibility in this population. To identify the gene(s) involved, a genome scan with replication using two subsets of these larger pedigrees with power to detect linkage is in progress.

  5. Role of Genomic Typing in Taxonomy, Evolutionary Genetics, and Microbial Epidemiology

    PubMed Central

    van Belkum, Alex; Struelens, Marc; de Visser, Arjan; Verbrugh, Henri; Tibayrenc, Michel

    2001-01-01

    Currently, genetic typing of microorganisms is widely used in several major fields of microbiological research. Taxonomy, research aimed at elucidation of evolutionary dynamics or phylogenetic relationships, population genetics of microorganisms, and microbial epidemiology all rely on genetic typing data for discrimination between genotypes. Apart from being an essential component of these fundamental sciences, microbial typing clearly affects several areas of applied microbiogical research. The epidemiological investigation of outbreaks of infectious diseases and the measurement of genetic diversity in relation to relevant biological properties such as pathogenicity, drug resistance, and biodegradation capacities are obvious examples. The diversity among nucleic acid molecules provides the basic information for all fields described above. However, researchers in various disciplines tend to use different vocabularies, a wide variety of different experimental methods to monitor genetic variation, and sometimes widely differing modes of data processing and interpretation. The aim of the present review is to summarize the technological and fundamental concepts used in microbial taxonomy, evolutionary genetics, and epidemiology. Information on the nomenclature used in the different fields of research is provided, descriptions of the diverse genetic typing procedures are presented, and examples of both conceptual and technological research developments for Escherichia coli are included. Recommendations for unification of the different fields through standardization of laboratory techniques are made. PMID:11432813

  6. Analysis of bronchial reactivity in epidemiological studies.

    PubMed Central

    Abramson, M J; Saunders, N A; Hensley, M J

    1990-01-01

    The measurement of bronchial reactivity in epidemiological studies has the advantage of quantifying an objective physiological feature of asthma. Bronchial reactivity was developed in a clinical setting and has been conventionally expressed as the dose of agonist producing a 20% fall in FEV1 (PD20). As PD20 can be estimated for less than 20% of subjects in general community surveys with the doses of agonist that are usually given, data from most subjects must be censored. Thus PD20 alone is a poor index of bronchial reactivity for epidemiological studies. Data from 809 aluminium smelter workers were used to evaluate alternative methods of analysing bronchial reactivity. Dose-response relationships were analysed by four methods: (1) PD20 by the conventional method of interpolating the dose on a logarithmic scale between the last two measurements of FEV1; (2) PD20 (with allowance for extrapolation), estimated by fitting an exponential curve to the dose-response data; (3) the linear regression slope between dose and FEV1 when significant; (4) the dose-response slope obtained in all subjects as the % change in FEV1 from baseline in response to total dose. When each of these measures was related to symptoms, diagnosis, and treatment of asthma, all differentiated between "asthmatic" and "non-asthmatic" subjects. The dose-response slope (method 4) had the advantages of simplicity and no censored data, and was shown to be clinically relevant. It is suggested that the dose-response slope should be used for the analysis of bronchial reactivity in epidemiological studies. PMID:2281424

  7. Genomic DNA extraction from whole blood stored from 15- to 30-years at -20 °C by rapid phenol-chloroform protocol: a useful tool for genetic epidemiology studies.

    PubMed

    Di Pietro, Fabio; Ortenzi, Francesco; Tilio, Martina; Concetti, Fabio; Napolioni, Valerio

    2011-02-01

    Long-term stored (LTS) whole blood collection can be an important source of DNA without collection costs, but there is a lack of information on methods useful to extract genomic DNA from such type of biological material. Here we report a simple and fast revisited phenol/chloroform extraction method from LTS whole blood. Protocol reliability was assessed by comparison with proteinase K and silica-gel membrane spin column-based DNA extraction methods using LTS -20 °C whole blood from 1980, and by testing it on 82 whole blood samples, collected from 1980 to 1995, with high quality (A(260/280) = 1.79 ± 0.32 O.D., A(260/230) = 1.45 ± 0.52 O.D.) and quantity results. Genotyping efficiency was also checked by performing RFLP-PCR and ASP-PCR of p53 Pro72Arg (rs1042522) SNP and hTERT MNS16A VNTR, respectively, resulting in 100% of samples successfully typed. In addition to the goodness and the efficiency of method proposed here, this protocol achieves working time reduction combining extraction and purification steps, allowing to work at room temperature. Furthermore, phenol is able to inactivate any potential nuclease and potential infective sources from the first step on. Based on these results we also conclude that LTS -20 °C whole blood samples may be considered a reliable and potential resource for future genotyping studies and retrospective analysis in a genetic epidemiological setting.

  8. From genetics to dietetics: the contribution of epidemiology to understanding Alzheimer's disease.

    PubMed

    Barberger-Gateau, Pascale; Lambert, Jean-Charles; Féart, Catherine; Pérès, Karine; Ritchie, Karen; Dartigues, Jean-François; Alpérovitch, Annick

    2013-01-01

    Late-life dementia results from non-modifiable risk factors such as age and genetics, modulated by deleterious and protective environmental factors among which nutrition may play a major role. This paper highlights five major recent contributions of the French Three-City (3C) and PAQUID epidemiological studies to Alzheimer's disease (AD) knowledge, targeting genetic and dietary risk factors, and the impact of cognitive decline in daily living. The 3C study contributed to a large genome-wide association study to identify new genetic risk factors for AD. In addition to apolipoprotein E (APOE), two loci gave replicated evidence of association: one within CLU, encoding clusterin or apolipoprotein J, and the other within CR1, encoding the complement component receptor 1. Although the attributable fraction of risk for these polymorphisms is moderate, genetic studies provide significant insights into the molecular bases of AD. Regarding dietary data, findings from 3C suggest that healthy diets associating sources of both omega 3 fatty acids (fish) and antioxidants (fruits and vegetables) such as the Mediterranean diet, and caffeine could be associated with decreased risk for AD. However, the protective effect of omega3 fatty acids might be limited to APOE4 non-carriers. Future research should focus on gene-nutrient interactions. Regarding the functional impact of prodromal AD, the PAQUID study showed that taking into account mild functional limitations considerably increases the predictive value of neuropsychological tests for conversion to dementia. Research should focus on sensitive instruments to capture early functional decline to improve the identification of elderly patients at high risk of conversion to dementia. PMID:22683527

  9. Temporal patterns of genetic and phenotypic variation in the epidemiologically important drone fly, Eristalis tenax.

    PubMed

    Francuski, Lj; Matić, I; Ludoški, J; Milankov, V

    2011-06-01

    Eristalis tenax L. (Diptera: Syrphidae) is commonly known as the drone fly (adult) or rat-tailed maggot (immature). Both adults and immature stages are identified as potential mechanical vectors of mycobacterial pathogens, and early-stage maggots cause accidental myiasis. We compared four samples from Mount Fruška Gora, Serbia, with the aim of obtaining insights into the temporal variations and sexual dimorphism in the species. This integrative approach was based on allozyme loci, morphometric wing parameters (shape and size) and abdominal colour patterns. Consistent sexual dimorphism was observed, indicating that male specimens had lighter abdomens and smaller and narrower wings than females. The distribution of genetic diversity at polymorphic loci indicated genetic divergence among collection dates. Landmark-based geometric morphometrics revealed, contrary to the lack of divergence in wing size, significant wing shape variation throughout the year. In addition, temporal changes in the frequencies of the abdominal patterns observed are likely to relate to the biology of the species and ecological factors in the locality. Hence, the present study expands our knowledge of the genetic diversity and phenotypic plasticity of E. tenax. The quantification of such variability represents a step towards the evaluation of the adaptive potential of this species of medical and epidemiological importance.

  10. Spatial and genetic epidemiology of hookworm in a rural community in Uganda.

    PubMed

    Pullan, Rachel L; Kabatereine, Narcis B; Quinnell, Rupert J; Brooker, Simon

    2010-06-15

    There are remarkably few contemporary, population-based studies of intestinal nematode infection for sub-Saharan Africa. This paper presents a comprehensive epidemiological analysis of hookworm infection intensity in a rural Ugandan community. Demographic, kinship, socioeconomic and environmental data were collected for 1,803 individuals aged six months to 85 years in 341 households in a cross-sectional community survey. Hookworm infection was assessed by faecal egg count. Spatial variation in the intensity of infection was assessed using a Bayesian negative binomial spatial regression model and the proportion of variation explained by host additive genetics (heritability) and common domestic environment was estimated using genetic variance component analysis. Overall, the prevalence of hookworm was 39.3%, with the majority of infections (87.7%) of light intensity (genetic relatedness is not a major determinant of infection intensity in this community, with exposure-related factors playing a greater role.

  11. Temporal patterns of genetic and phenotypic variation in the epidemiologically important drone fly, Eristalis tenax.

    PubMed

    Francuski, Lj; Matić, I; Ludoški, J; Milankov, V

    2011-06-01

    Eristalis tenax L. (Diptera: Syrphidae) is commonly known as the drone fly (adult) or rat-tailed maggot (immature). Both adults and immature stages are identified as potential mechanical vectors of mycobacterial pathogens, and early-stage maggots cause accidental myiasis. We compared four samples from Mount Fruška Gora, Serbia, with the aim of obtaining insights into the temporal variations and sexual dimorphism in the species. This integrative approach was based on allozyme loci, morphometric wing parameters (shape and size) and abdominal colour patterns. Consistent sexual dimorphism was observed, indicating that male specimens had lighter abdomens and smaller and narrower wings than females. The distribution of genetic diversity at polymorphic loci indicated genetic divergence among collection dates. Landmark-based geometric morphometrics revealed, contrary to the lack of divergence in wing size, significant wing shape variation throughout the year. In addition, temporal changes in the frequencies of the abdominal patterns observed are likely to relate to the biology of the species and ecological factors in the locality. Hence, the present study expands our knowledge of the genetic diversity and phenotypic plasticity of E. tenax. The quantification of such variability represents a step towards the evaluation of the adaptive potential of this species of medical and epidemiological importance. PMID:21414022

  12. Jumping on the Train of Personalized Medicine: A Primer for Non-Geneticist Clinicians: Part 2. Fundamental Concepts in Genetic Epidemiology

    PubMed Central

    Li, Aihua; Meyre, David

    2014-01-01

    With the decrease in sequencing costs, personalized genome sequencing will eventually become common in medical practice. We therefore write this series of three reviews to help non-geneticist clinicians to jump into the fast-moving field of personalized medicine. In the first article of this series, we reviewed the fundamental concepts in molecular genetics. In this second article, we cover the key concepts and methods in genetic epidemiology including the classification of genetic disorders, study designs and their implementation, genetic marker selection, genotyping and sequencing technologies, gene identification strategies, data analyses and data interpretation. This review will help the reader critically appraise a genetic association study. In the next article, we will discuss the clinical applications of genetic epidemiology in the personalized medicine area. PMID:25598767

  13. Epidemiology.

    PubMed

    Walsh, Kyle M; Ohgaki, Hiroko; Wrensch, Margaret R

    2016-01-01

    More than 250,000 new cases of primary malignant brain tumors are diagnosed annually worldwide, 77% of which are gliomas. A small proportion of gliomas are caused by the inheritance of rare high-penetrance genetic variants or high-dose radiation. Since 2009, inherited genetic variants in 10 regions near eight different genes have been consistently associated with glioma risk via genome-wide association studies. Most of these variants increase glioma risk by 20-40%, but two have higher relative risks. One on chromosome 8 increases risk of IDH-mutated gliomas sixfold and another that affects TP53 function confers a 2.5-fold increased risk of glioma. Functions of some of the other risk variants are known or suspected, but future research will determine functions of other risk loci. Recent progress also has been made in defining subgroups of glioma based on acquired alterations within tumors. Allergy history has been consistently associated with reduced glioma risk, though the mechanisms have not yet been clarified. Future studies will need to be large enough so that environmental and constitutive genetic risk factors can be examined within molecularly defined, etiologically homogeneous subgroups.

  14. Genetic Epidemiology and Preventive Healthcare in Multiethnic Societies: The Hemoglobinopathies

    PubMed Central

    Giordano, Piero C.; Harteveld, Cornelis L.; Bakker, Egbert

    2014-01-01

    Healthy carriers of severe Hemoglobinopathies are usually asymptomatic and only efficiently detected through screening campaigns. Based upon epidemiological data, screenings have been offered for decades to populations of endemic Southern Europe for primary prevention of Thalassemia Major, while for many populations of the highly endemic African and Asian countries prevention for Sickle Cell Disease and Thalassemia Major is mainly unavailable. The massive migrations of the last decades have brought many healthy carriers of these diseases to live and reproduce in non-endemic immigration areas changing the epidemiological pattern of the local recessive diseases and bringing an urgent need for treatment and primary prevention in welfare countries. Nonetheless, no screening for an informed reproductive choice is actively offered by the healthcare systems of most of these welfare countries. As a consequence more children affected with severe Hemoglobinopathies are born today in the immigration countries of Northern Europe than in the endemic Southern European area. Following the Mediterranean example, some countries like the UK and The Netherlands have been offering early pregnancy carrier screening at different levels and/or in specific areas but more accessible measures need to be taken at the national level in all immigration countries. Identification of carriers using simple and inexpensive methods should be included in the Rhesus and infectious diseases screening which is offered early in pregnancy in most developed countries. This would allow identification of couples at risk in time for an informed choice and for prenatal diagnosis if required before the first affected child is born. PMID:24921462

  15. Genetic epidemiology, prevalence, and genotype–phenotype correlations in the Swedish population with osteogenesis imperfecta

    PubMed Central

    Lindahl, Katarina; Åström, Eva; Rubin, Carl-Johan; Grigelioniene, Giedre; Malmgren, Barbro; Ljunggren, Östen; Kindmark, Andreas

    2015-01-01

    Osteogenesis imperfecta (OI) is a rare hereditary bone fragility disorder, caused by collagen I mutations in 90% of cases. There are no comprehensive genotype–phenotype studies on >100 families outside North America, and no population-based studies determining the genetic epidemiology of OI. Here, detailed clinical phenotypes were recorded, and the COL1A1 and COL1A2 genes were analyzed in 164 Swedish OI families (223 individuals). Averages for bone mineral density (BMD), height and yearly fracture rate were calculated and related to OI and mutation type. N-terminal helical mutations in both the α1- and α2-chains were associated with the absence of dentinogenesis imperfecta (P<0.0001 vs 0.0049), while only those in the α1-chain were associated with blue sclera (P=0.0110). Comparing glycine with serine substitutions, α1-alterations were associated with more severe phenotype (P=0.0031). Individuals with type I OI caused by qualitative vs quantitative mutations were shorter (P<0.0001), but did not differ considering fractures or BMD. The children in this cohort were estimated to represent >95% of the complete Swedish pediatric OI population. The prevalence of OI types I, III, and IV was 5.16, 0.89, and 1.35/100 000, respectively (7.40/100 000 overall), corresponding to what has been estimated but not unequivocally proven in any population. Collagen I mutation analysis was performed in the family of 97% of known cases, with causative mutations found in 87%. Qualitative mutations caused 32% of OI type I. The data reported here may be helpful to predict phenotype, and describes for the first time the genetic epidemiology in >95% of an entire OI population. PMID:25944380

  16. Genetic epidemiology, prevalence, and genotype-phenotype correlations in the Swedish population with osteogenesis imperfecta.

    PubMed

    Lindahl, Katarina; Åström, Eva; Rubin, Carl-Johan; Grigelioniene, Giedre; Malmgren, Barbro; Ljunggren, Östen; Kindmark, Andreas

    2015-08-01

    Osteogenesis imperfecta (OI) is a rare hereditary bone fragility disorder, caused by collagen I mutations in 90% of cases. There are no comprehensive genotype-phenotype studies on >100 families outside North America, and no population-based studies determining the genetic epidemiology of OI. Here, detailed clinical phenotypes were recorded, and the COL1A1 and COL1A2 genes were analyzed in 164 Swedish OI families (223 individuals). Averages for bone mineral density (BMD), height and yearly fracture rate were calculated and related to OI and mutation type. N-terminal helical mutations in both the α1- and α2-chains were associated with the absence of dentinogenesis imperfecta (P<0.0001 vs 0.0049), while only those in the α1-chain were associated with blue sclera (P=0.0110). Comparing glycine with serine substitutions, α1-alterations were associated with more severe phenotype (P=0.0031). Individuals with type I OI caused by qualitative vs quantitative mutations were shorter (P<0.0001), but did not differ considering fractures or BMD. The children in this cohort were estimated to represent >95% of the complete Swedish pediatric OI population. The prevalence of OI types I, III, and IV was 5.16, 0.89, and 1.35/100 000, respectively (7.40/100 000 overall), corresponding to what has been estimated but not unequivocally proven in any population. Collagen I mutation analysis was performed in the family of 97% of known cases, with causative mutations found in 87%. Qualitative mutations caused 32% of OI type I. The data reported here may be helpful to predict phenotype, and describes for the first time the genetic epidemiology in >95% of an entire OI population.

  17. Genetic relationships and epidemiological links between wild type 1 poliovirus isolates in Pakistan and Afghanistan

    PubMed Central

    2012-01-01

    Background/Aim Efforts have been made to eliminate wild poliovirus transmission since 1988 when the World Health Organization began its global eradication campaign. Since then, the incidence of polio has decreased significantly. However, serotype 1 and serotype 3 still circulate endemically in Pakistan and Afghanistan. Both countries constitute a single epidemiologic block representing one of the three remaining major global reservoirs of poliovirus transmission. In this study we used genetic sequence data to investigate transmission links among viruses from diverse locations during 2005-2007. Methods In order to find the origins and routes of wild type 1 poliovirus circulation, polioviruses were isolated from faecal samples of Acute Flaccid Paralysis (AFP) patients. We used viral cultures, two intratypic differentiation methods PCR, ELISA to characterize as vaccine or wild type 1 and nucleic acid sequencing of entire VP1 region of poliovirus genome to determine the genetic relatedness. Results One hundred eleven wild type 1 poliovirus isolates were subjected to nucleotide sequencing for genetic variation study. Considering the 15% divergence of the sequences from Sabin 1, Phylogenetic analysis by MEGA software revealed that active inter and intra country transmission of many genetically distinct strains of wild poliovirus type 1 belonged to genotype SOAS which is indigenous in this region. By grouping wild type 1 polioviruses according to nucleotide sequence homology, three distinct clusters A, B and C were obtained with multiple chains of transmission together with some silent circulations represented by orphan lineages. Conclusion Our results emphasize that there was a persistent transmission of wild type1 polioviruses in Pakistan and Afghanistan during 2005-2007. The epidemiologic information provided by the sequence data can contribute to the formulation of better strategies for poliomyelitis control to those critical areas, associated with high risk

  18. Epidemiologic study of canine blastomycosis in Wisconsin.

    PubMed

    Archer, J R; Trainer, D O; Schell, R F

    1987-05-15

    An epidemiologic study was designed to investigate the increasing number of cases of canine blastomycosis being reported in Wisconsin. From January 1980 through July 1982, 200 cases of canine blastomycosis from 39 Wisconsin counties were examined to assess epidemiologic and environmental aspects of this disease. Based on a survey of 176 dog owners, principal disease characteristics for canine blastomycosis were anorexia, lethargy, shortness of breath, chronic cough, and weight loss. The greatest number of cases of canine blastomycosis was in the northwest, north central, northeast, central, and southeast regions of Wisconsin. The northeast and central regions were determined to be new enzootic areas. Sporting breeds accounted for the largest percentage of cases among the various breeds of dogs in Wisconsin. Most of the affected dogs were 3 years old or younger and there was no apparent sexual predilection. Canine blastomycosis was diagnosed more frequently from late spring through late fall. Enzootic areas, except for the southeast region of Wisconsin, were located where the soil was sandy and acid. The results of this study suggested a possible association of enzootic areas with waterways, especially impoundments.

  19. Environmental and genetic contributors to hypospadias: a review of the epidemiologic evidence.

    PubMed

    Carmichael, Suzan L; Shaw, Gary M; Lammer, Edward J

    2012-07-01

    This review evaluates current knowledge related to trends in the prevalence of hypospadias, the association of hypospadias with endocrine-disrupting exposures, and the potential contribution of genetic susceptibility to its etiology. The review focuses on epidemiologic evidence. Increasing prevalence of hypospadias has been observed, but such increases tend to be localized to specific regions or time periods. Thus, generalized statements that hypospadias is increasing are unsupported. Owing to the limitations of study designs and inconsistent results, firm conclusions cannot be made regarding the association of endocrine-disrupting exposures with hypospadias. Studies with more rigorous study designs (e.g., larger and more detailed phenotypes) and exposure assessment that encompasses more breadth and depth (e.g., specific endocrine-related chemicals) will be critical to make better inferences about these important environmental exposures. Many candidate genes for hypospadias have been identified, but few of them have been examined to an extent that enables solid conclusions. Further study is needed that includes larger sample sizes, comparison groups that are more representative of the populations from which the cases were derived, phenotype-specific analyses, and more extensive exploration of variants. In conclusion, examining the associations of environmental and genetic factors with hypospadias remain important areas of inquiry, although our actual understanding of their contribution to hypospadias risk in humans is currently limited.

  20. Environmental and Genetic Contributors to Hypospadias: A Review of the Epidemiologic Evidence

    PubMed Central

    Carmichael, Suzan L.; Shaw, Gary M.; Lammer, Edward J.

    2012-01-01

    This review evaluates current knowledge related to trends in the prevalence of hypospadias, the association of hypospadias with endocrine-disrupting exposures, and the potential contribution of genetic susceptibility to its etiology. The review focuses on epidemiologic evidence. Increasing prevalence of hypospadias has been observed, but such increases tend to be localized to specific regions or time periods. Thus, generalized statements that hypospadias is increasing are unsupported. Due to limitations of study designs and inconsistent results, firm conclusions cannot be made regarding the association of endocrine-disrupting exposures with hypospadias. Studies with more rigorous study designs (e.g., larger and more detailed phenotypes) and exposure assessment that encompasses more breadth as well as depth (e.g., specific endocrine-related chemicals) will be critical to make better inferences about these important environmental exposures. Many candidate genes for hypospadias have been identified, but few of them have been examined to an extent that enables solid conclusions. Further studies are needed that include larger sample sizes, comparison groups that are more representative of the populations from which the cases were derived, phenotype-specific analyses, and more extensive exploration of variants. In conclusion, examining the associations of environmental and genetic factors with hypospadias remain important areas of inquiry, although our actual understanding of their contribution to hypospadias risk in humans is currently limited. PMID:22678668

  1. Epidemiological study of salivary gland tumours.

    PubMed

    Frade Gonzalez, C; Lozano Ramirez, A; Garcia Caballero, T; Labella Caballero, T

    1999-01-01

    Tumours located in the salivary glands form the most heterogeneous group in all human oncological pathology. They show various epidemiological, clinical and evolutionary characteristics which separate them from other neoplasms of the head and neck. In this paper, we have carried out a study on their epidemiological aspects, collecting 80 cases diagnosed in the ENT Service of the University Hospital Complex of Santiago over 17 years. The incidence was 1.22 cases per 100,000 inhabitants per year. The frequency was higher in males (58.75%) and in the 7th decade of age. A predominance was noticed in females under 40 years of age and in males over this age, but the differences were not statistically significant. The most frequent site was the parotid gland, and we could not find any case in the sublingual gland. In 52.5% of cases the tumour was benign, pleomorphic adenoma being the most prevalent. Among malignant tumours, the epidermoid carcinoma stood out in our series. The prevalence of benign tumours in females and of malignant tumours in males was clear, with significant differences. We compare our results with the data published in the literature.

  2. The Molecular Epidemiology and Genetic Environment of Carbapenemases Detected in Africa.

    PubMed

    Sekyere, John Osei; Govinden, Usha; Essack, Sabiha

    2016-01-01

    Research articles describing carbapenemases and their genetic environments in Gram-negative bacteria were reviewed to determine the molecular epidemiology of carbapenemases in Africa. The emergence of resistance to the carbapenems, the last resort antibiotic for difficult to treat bacterial infections, affords clinicians few therapeutic options, with a resulting increase in morbidities, mortalities, and healthcare costs. However, the molecular epidemiology of carbapenemases throughout Africa is less described. Research articles and conference proceedings describing the genetic environment and molecular epidemiology of carbapenemases in Africa were retrieved from Google Scholar, Scifinder, Pubmed, Web of Science, and Science Direct databases. Predominant carbapenemase genes so far described in Africa include the blaOXA-48 type, blaIMP, blaVIM, and blaNDM in Acinetobacter baumannii, Klebsiella pneumoniae, Enterobacter cloacae, Citrobacter spp., and Escherichia coli carried on various plasmid types and sizes, transposons, and integrons. Class D and class B carbapenemases, mainly prevalent in A. baumannii, K. pneumoniae, E. cloacae, Citrobacter spp., and E. coli were the commonest carbapenemases. Carbapenemases are mainly reported in North and South Africa as under-resourced laboratories, lack of awareness and funding preclude the detection and reporting of carbapenemase-mediated resistance. Consequently, the true molecular epidemiology of carbapenemases and their genetic environment in Africa is still unknown.

  3. NASA Remote Sensing Data for Epidemiological Studies

    NASA Technical Reports Server (NTRS)

    Maynard, Nancy G.; Vicente, G. A.

    2002-01-01

    In response to the need for improved observations of environmental factors to better understand the links between human health and the environment, NASA has established a new program to significantly improve the utilization of NASA's diverse array of data, information, and observations of the Earth for health applications. This initiative, lead by Goddard Space Flight Center (GSFC) has the following goals: (1) To encourage interdisciplinary research on the relationships between environmental parameters (e.g., rainfall, vegetation) and health, (2) Develop practical early warning systems, (3) Create a unique system for the exchange of Earth science and health data, (4) Provide an investigator field support system for customers and partners, (5) Facilitate a system for observation, identification, and surveillance of parameters relevant to environment and health issues. The NASA Environment and Health Program is conducting several interdisciplinary projects to examine applications of remote sensing data and information to a variety of health issues, including studies on malaria, Rift Valley Fever, St. Louis Encephalitis, Dengue Fever, Ebola, African Dust and health, meningitis, asthma, and filariasis. In addition, the NASA program is creating a user-friendly data system to help provide the public health community with easy and timely access to space-based environmental data for epidemiological studies. This NASA data system is being designed to bring land, atmosphere, water and ocean satellite data/products to users not familiar with satellite data/products, but who are knowledgeable in the Geographic Information Systems (GIS) environment. This paper discusses the most recent results of the interdisciplinary environment-health research projects and provides an analysis of the usefulness of the satellite data to epidemiological studies. In addition, there will be a summary of presently-available NASA Earth science data and a description of how it may be obtained.

  4. [Epidemiological Studies On The Acaroid Mite

    PubMed

    Chu, Jung Kyun; Song, Soo Bok; Kim, Don Kyun; Kim, Yeong Kyu

    1967-06-01

    Epidemiological study on Acaroid mite in dust different sites were carried out and the following results were obtained. 1. Tyrophagus dimidiatus, Chibidania tokyoensis and Ornithonyssus nagayoi were found in living room(46.2 %), bath room(36.7 %), garden(27.0 %), shopping-store(28.8 %) and ware-house (29.2 %) in the Pusan area. 2. Dermanyssus gallinae and Rhizoglyphus echinopus were found mainly in class rooms of girl's high school(34.0 %) and class room of girl's middle school(40.0 %) as well as in primary school(13.2 %), but they are not found in class rooms of boys high school. 3. Generally, the various mites were found in the living room(57.0 %), under the carpet(50 %), under the furniture(52.0 %), on the furniture(27.5 %), lavatory(35.7 %) and garden(23.8 %).

  5. Disentangling the genetic origins of a plant pathogen during disease spread using an original molecular epidemiology approach.

    PubMed

    Xhaard, Constance; Barrès, Benoît; Andrieux, Axelle; Bousset, Lydia; Halkett, Fabien; Frey, Pascal

    2012-05-01

    The advent of molecular epidemiology has greatly improved our ability to identify the population sources and track the pathogen movement. Yet the wide spatial and temporal scales usually considered are useful only to infer historical migration pathways. In this study, Bayesian genetic assignments and a landscape epidemiology approach were combined to unravel genetic origin and annual spread during a single epidemic of a plant pathogen: the poplar rust fungus Melampsora larici-populina. The study focused on a particular area-the Durance River valley-which enabled inoculum sources to be identified and channelled spread of the epidemic along a one-dimensional corridor. Spatio-temporal monitoring of disease showed that the epidemic began in the upstream part of the valley and spread out downstream. Using genetic assignment tests, individuals collected at the end of the epidemic were sorted into two genetic groups; very few hybrids were detected, although individuals from both groups coexisted locally downstream in the valley. The epidemic originated from two genetically distinct inoculum sources. Individuals of each group then dispersed southwards along the Durance River and became mixed in poplar riparian stands. These two genetic groups were found previously at a wider spatial scale and proved to result from distinct evolutionary histories on either wild or cultivated poplars. This study showed that the two groups can mix during an epidemic but do not hybridize because they then reproduce asexually. In general, the methods employed here could be useful for elucidating the genetic origin and retracing the colonization history and migration pathways of recent epidemics.

  6. Epstein- Barr Virus: Clinical and Epidemiological Revisits and Genetic Basis of Oncogenesis

    PubMed Central

    Ali, Abdelwahid Saeed; Al-Shraim, Mubarak; Al-Hakami, Ahmed Musa; Jones, Ian M

    2015-01-01

    Epstein-Barr virus (EBV) is classified as a member in the order herpesvirales, family herpesviridae, subfamily gammaherpesvirinae and the genus lymphocytovirus. The virus is an exclusively human pathogen and thus also termed as human herpesvirus 4 (HHV4). It was the first oncogenic virus recognized and has been incriminated in the causation of tumors of both lymphatic and epithelial nature. It was reported in some previous studies that 95% of the population worldwide are serologically positive to the virus. Clinically, EBV primary infection is almost silent, persisting as a life-long asymptomatic latent infection in B cells although it may be responsible for a transient clinical syndrome called infectious mononucleosis. Following reactivation of the virus from latency due to immunocompromised status, EBV was found to be associated with several tumors. EBV linked to oncogenesis as detected in lymphoid tumors such as Burkitt's lymphoma (BL), Hodgkin's disease (HD), post-transplant lymphoproliferative disorders (PTLD) and T-cell lymphomas (e.g. Peripheral T-cell lymphomas; PTCL and Anaplastic large cell lymphomas; ALCL). It is also linked to epithelial tumors such as nasopharyngeal carcinoma (NPC), gastric carcinomas and oral hairy leukoplakia (OHL). In vitro, EBV many studies have demonstrated its ability to transform B cells into lymphoblastoid cell lines (LCLs). Despite these malignancies showing different clinical and epidemiological patterns when studied, genetic studies have suggested that these EBV- associated transformations were characterized generally by low level of virus gene expression with only the latent virus proteins (LVPs) upregulated in both tumors and LCLs. In this review, we summarize some clinical and epidemiological features of EBV- associated tumors. We also discuss how EBV latent genes may lead to oncogenesis in the different clinical malignancies PMID:26862355

  7. Making blood 'Melanesian': fieldwork and isolating techniques in genetic epidemiology (1963-1976).

    PubMed

    Widmer, Alexandra

    2014-09-01

    'Isolated' populations did not exist unproblematically for life scientists to study. This article examines the practical and conceptual labour, and the historical contingencies that rendered populations legible as 'isolates' for population geneticists. Though a standard historiographical narrative tells us that population geneticists were moving from typological understandings of biological variation to processual ones, cultural variation was understood as vulnerable to homogenisation. I chart the importance that D. Carleton Gajdusek placed on isolates from his promotion of genetic epidemiology in WHO technical reports and at a Cold Spring Harbour symposium to his fieldwork routines and collection practices in a group of South Pacific islands. His fieldwork techniques combined social, cultural and historical knowledge of the research subjects in order to isolate biological descent using genealogies. Having isolated a population, Gajdusek incorporated biological materials derived from that population into broad categories of 'Melanesian' and 'race' to generate statements about the genetics of abnormal haemoglobins and malaria. Alongside an analysis of Gajdusek's practices, I present different narratives of descent, kinship and identities learned during my ethnographic work in Vanuatu. These alternatives show tacit decisions made pertaining to scale in the production of 'isolates'. PMID:25042975

  8. Dynamics of the ovarian reserve and impact of genetic and epidemiological factors on age of menopause.

    PubMed

    Pelosi, Emanuele; Simonsick, Eleanor; Forabosco, Antonino; Garcia-Ortiz, Jose Elias; Schlessinger, David

    2015-05-01

    The narrow standard age range of menopause, ∼50 yr, belies the complex balance of forces that govern the underlying formation and progressive loss of ovarian follicles (the "ovarian reserve" whose size determines the age of menopause). We show here the first quantitative graph of follicle numbers, distinguished from oocyte counts, across the reproductive lifespan, and review the current state of information about genetic and epidemiological risk factors in relation to possible preservation of reproductive capacity. In addition to structural X-chromosome changes, several genes involved in the process of follicle formation and/or maintenance are implicated in Mendelian inherited primary ovarian insufficiency (POI), with menopause before age 40. Furthermore, variants in a largely distinct cohort of reported genes-notably involved in pathways relevant to atresia, including DNA repair and cell death-have shown smaller but additive effects on the variation in timing of menopause in the normal range, early menopause (age <45), and POI. Epidemiological factors show effect sizes comparable to those of genetic factors, with smoking accounting for about 5% of the risk of early menopause, equivalent to the summed effect of the top 17 genetic variants. The identified genetic and epidemiological factors underline the importance of early detection of reproductive problems to enhance possible interventions.

  9. Mycobacterium bovis in Burkina Faso: Epidemiologic and Genetic Links between Human and Cattle Isolates

    PubMed Central

    Sanou, Adama; Tarnagda, Zekiba; Kanyala, Estelle; Zingué, Dezemon; Nouctara, Moumini; Ganamé, Zakaria; Combary, Adjima; Hien, Hervé; Dembele, Mathurin; Kabore, Antoinette; Meda, Nicolas; Van de Perre, Philippe; Neveu, Dorine

    2014-01-01

    Background In sub-Saharan Africa, bovine tuberculosis (bTB) is a potential hazard for animals and humans health. The goal of this study was to improve our understanding of bTB epidemiology in Burkina Faso and especially Mycobacterium bovis transmission within and between the bovine and human populations. Methodology/principal findings Twenty six M. bovis strains were isolated from 101 cattle carcasses with suspected bTB lesions during routine meat inspections at the Bobo Dioulasso and Ouagadougou slaughterhouses. In addition, 7 M. bovis strains were isolated from 576 patients with pulmonary tuberculosis. Spoligotyping, RDAf1 deletion and MIRU-VNTR typing were used for strains genotyping. The isolation of M. bovis strains was confirmed by spoligotyping and 12 spoligotype signatures were detected. Together, the spoligotyping and MIRU-VNTR data allowed grouping the 33 M. bovis isolates in seven clusters including isolates exclusively from cattle (5) or humans (1) or from both (1). Moreover, these data (genetic analyses and phenetic tree) showed that the M. bovis isolates belonged to the African 1 (Af1) clonal complex (81.8%) and the putative African 5 (Af5) clonal complex (18.2%), in agreement with the results of RDAf1 deletion typing. Conclusions/Significance This is the first detailed molecular characterization of M. bovis strains from humans and cattle in Burkina Faso. The distribution of the two Af1 and putative Af5 clonal complexes is comparable to what has been reported in neighbouring countries. Furthermore, the strain genetic profiles suggest that M. bovis circulates across the borders and that the Burkina Faso strains originate from different countries, but have a country-specific evolution. The genetic characterization suggests that, currently, M. bovis transmission occurs mainly between cattle, occasionally between cattle and humans and potentially between humans. This study emphasizes the bTB risk in cattle but also in humans and the difficulty to set up

  10. Epidemiological study of cauda equina syndrome

    PubMed Central

    Fuso, Fernando Augusto Freitas; Dias, André Luiz Natálio; Letaif, Olavo Biraghi; Cristante, Alexandre Fogaça; Marcon, Raphael Martus; de Barros, Tarcísio Eloy Pessoa

    2013-01-01

    OBJECTIVE : The primary purpose of this study was to determine the characteristics and outcomes of the patients admitted at our clinics diagnosed with cauda equina syndrome (CES). Secondarily, this study will serve as a basis for other comparative studies aiming at a better understanding of this condition and its epidemiology. METHODS : We conducted a retrospective study by reviewing the medical records of patients diagnosed with CES and neurogenic bladder between 2005 and 2011. The following variables were analyzed: gender, age, etiology, topographic level of the lesion, time between disease onset and diagnosis, presence of neurogenic bladder, time between diagnosis and surgery, neurological damage and neurogenic bladder persistence. RESULTS : Considering that CES is a rare condition, we were not able to establish statistic correlation between the analyzed variables and the outcomes of the disease. However, this study brought to light the inadequacy of our public health system in treating that kind of patient. CONCLUSION : The study shows that despite the well-defined basis for managing CES, we noted a greater number of patients with sequels caused by this condition, than is seen in the literature. The delayed diagnosis and, consequently, delayed treatment, were the main causes for the results observed. Level of Evidence IV, Case Series. PMID:24453661

  11. DESIGN OF EXPOSURE MEASUREMENTS FOR EPIDEMIOLOGIC STUDIES

    EPA Science Inventory

    This presentation will describe the following items: (1) London daily air pollution and deaths that demonstrate how time series epidemiology can indicate that air pollution caused death; (2) Sophisticated statistical models required to establish this relationship for lower pollut...

  12. Epidemiological Assessments of Skin Outcomes in the Nurses’ Health Studies

    PubMed Central

    Li, Wen-Qing; Cho, Eunyoung; Weinstock, Martin A.; Mashfiq, Hasan

    2016-01-01

    Objectives. To review the contribution of the Nurses’ Health Studies (NHSs) to identifying epidemiological factors associated with multiple skin diseases, including skin cancer, psoriasis, and other inflammatory and autoimmune skin diseases. Methods. We carried out a narrative review of NHS articles published between 1976 and 2016. Results. The NHSs have identified environmental and lifestyle factors related to psoriasis, supporting obesity and smoking as psoriasis risk factors; associations between psoriasis and diabetes, myocardial infarction, and Crohn’s disease, supporting psoriasis as a systemic disorder; and associations of pigmentary traits, ultraviolet radiation, and lifestyle factors such as citrus consumption with risk of skin cancer. Genetic studies have identified novel genetic loci for skin pigmentation (e.g., IRF4, SLC24A4, NID1, and EDNRB) and skin cancer (e.g., TET2 and HERC2-OCA2). Work continues on highly prevalent but less studied skin conditions such as rosacea, acne, and atopic dermatitis. The NHS results have influenced public health policies on indoor tanning devices. Conclusions. The NHSs have provided invaluable resources on skin disease population science and contributed to the etiological understanding of multiple skin disorders. PMID:27459457

  13. Molecular epidemiology, population genetics, and pathogenic role of Helicobacter pylori

    PubMed Central

    Suzuki, Rumiko; Shiota, Seiji; Yamaoka, Yoshio

    2012-01-01

    Helicobacter pylori infection is linked to various gastroduodenal diseases; however, only approximately 20% of infected individuals develop severe diseases. Despite the high prevalence of H. pylori infection in Africa and South Asia, the incidence of gastric cancer in these areas is much lower than in other countries. Furthermore, the incidence of gastric cancer tends to decrease from north to south in East Asia. Such geographic differences in the pathology can be explained, at least in part, by the presence of different types of H. pylori virulence factors, especially cagA, vacA, and the right end of the cag pathogenicity island. The genotype of the virulence genes is also useful as a tool to track human migration utilizing the high genetic diversity and frequent recombination between different H. pylori strains. Multilocus sequence typing (MLST) analysis using 7 housekeeping genes can also help predict the history of human migrations. Population structure analysis based on MLST has revealed 7 modern population types of H. pylori, which derived from 6 ancestral populations. Interestingly, the incidence of gastric cancer is closely related to the distribution of H. pylori populations. The different incidence of gastric cancer can be partly attributed to the different genotypes of H. pylori circulating in different geographic areas. Although approaches by MLST and virulence factors are effective, these methods focus on a small number of genes and may miss information conveyed by the rest of the genome. Genome-wide analyses using DNA microarray or whole-genome sequencing technology give a broad view on the genome of H. pylori. In particular, next-generation sequencers, which can read DNA sequences in less time and at lower costs than Sanger sequencing, enabled us to efficiently investigate not only the evolution of H. pylori, but also novel virulence factors and genomic changes related to drug resistance. PMID:22197766

  14. Genetic features of Huntington disease in Cuban population: implications for phenotype, epidemiology and predictive testing.

    PubMed

    Vázquez-Mojena, Yaimeé; Laguna-Salvia, Leonides; Laffita-Mesa, José M; González-Zaldívar, Yanetza; Almaguer-Mederos, Luis E; Rodríguez-Labrada, Roberto; Almaguer-Gotay, Dennis; Zayas-Feria, Pedro; Velázquez-Pérez, Luis

    2013-12-15

    Huntington disease is the most frequent polyglutamine disorder with variable worldwide prevalence. Although some Latin American populations have been studied, HD prevalence in Cuban population remains unknown. In order to characterize the disease in Cuba, the relative frequency of HD was determined by studying 130 patients with chorea and 63 unrelated healthy controls, emphasizing in the molecular epidemiology of the disease. Sixty-two patients with chorea belonging to 16 unrelated families carried a pathological CAG expansion in the HTT gene, ranging from 39 to 67 repeats. Eighty-three percent of them come from the eastern region of the country. A significant inverse correlation between age at onset and expanded CAG repeats was seen. Intermediate alleles in affected individuals and controls represented 4.8% and 3.97% respectively, which have been a putative source of de novo mutation. This study represents the largest molecular characterization of Huntington disease in the Cuban population. These results may have significant implications for an understanding of the disease, its diagnosis and prognosis in Cuban patients, giving health professionals the tools to implement confirmatory genetic testing, pre-symptomatic testing and clinical trials in this population.

  15. 40 CFR 159.170 - Human epidemiological and exposure studies.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Human epidemiological and exposure... Information § 159.170 Human epidemiological and exposure studies. Information must be submitted which concerns... that a correlation may exist between exposure to a pesticide and observed adverse effects in...

  16. 40 CFR 159.170 - Human epidemiological and exposure studies.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Human epidemiological and exposure... Information § 159.170 Human epidemiological and exposure studies. Information must be submitted which concerns... that a correlation may exist between exposure to a pesticide and observed adverse effects in...

  17. EPIDEMIOLOGIC STUDIES OF DISINFECTANTS AND DISINFECTANT BY-PRODUCTS

    EPA Science Inventory

    This article provides a review of the epidemiologic evidence for human health effects that may be associated with the disinfection of drinking water. An epidemiologic study attempts to link human health effects with exposure to a specific agent (e.g., DBCM), agents (e.g., THMs or...

  18. 40 CFR 159.170 - Human epidemiological and exposure studies.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Human epidemiological and exposure... Information § 159.170 Human epidemiological and exposure studies. Information must be submitted which concerns... that a correlation may exist between exposure to a pesticide and observed adverse effects in...

  19. 40 CFR 159.170 - Human epidemiological and exposure studies.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Human epidemiological and exposure... Information § 159.170 Human epidemiological and exposure studies. Information must be submitted which concerns... that a correlation may exist between exposure to a pesticide and observed adverse effects in...

  20. 40 CFR 159.170 - Human epidemiological and exposure studies.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Human epidemiological and exposure... Information § 159.170 Human epidemiological and exposure studies. Information must be submitted which concerns... that a correlation may exist between exposure to a pesticide and observed adverse effects in...

  1. Review, discussion, and summary of epidemiological studies.

    PubMed

    Shy, C M

    1989-02-01

    This paper reviews and summarizes the epidemiological studies presented at the Symposium on the Health Effects of Acid Aerosols. Two studies of acute episodes examined different indicators of respiratory morbidity before, during, and after the January 1985 air pollution event in western Europe. In the U.K. no increase in respiratory morbidity, as reported by a group of general practitioners, was observed, but measured concentrations of air pollutants failed to substantiate the existence of an identifiable episode. In the Federal Republic of Germany, the air pollution episode was documented and was associated with a 10 to 25% increase in several indicators of respiratory and cardiovascular morbidity, but could not be attributed to acidic aerosols as such. In two further studies, investigators related day-to-day variations in air pollution with admissions to acute care hospitals in southern Ontario for respiratory disease over a 9-year period, and with daily mortality in London from 1963 to 1972. In the study of hospital admissions, significant correlations were observed with sulfate, ozone, and SO2 pollution, but the data were insufficient to isolate the separate or combined effects of these pollutants. In the London mortality analysis, the strongest correlations were observed for sulfuric acid levels of the prior day, but prefiltering of the mortality data may have dampened the true relationship, and age- and cause-specific analyses would have been desirable. Finally two reports on chronic effects of residence in high air pollution areas have thus far made little contribution to the evidence for an adverse effect of specific pollutants.

  2. Choosing an appropriate bacterial typing technique for epidemiologic studies

    PubMed Central

    Foxman, Betsy; Zhang, Lixin; Koopman, James S; Manning, Shannon D; Marrs, Carl F

    2005-01-01

    A wide variety of bacterial typing systems are currently in use that vary greatly with respect to the effort required, cost, reliability and ability to discriminate between bacterial strains. No one technique is optimal for all forms of investigation. We discuss the desired level of discrimination and need for a biologic basis for grouping strains of apparently different types when using bacterial typing techniques for different epidemiologic applications: 1) confirming epidemiologic linkage in outbreak investigations, 2) generating hypotheses about epidemiologic relationships between bacterial strains in the absence of epidemiologic information, and 3) describing the distributions of bacterial types and identifying determinants of those distributions. Inferences made from molecular epidemiologic studies of bacteria depend upon both the typing technique selected and the study design used; thus, choice of typing technique is pivotal for increasing our understanding of the pathogenesis and transmission, and eventual disease prevention. PMID:16309556

  3. An Exercise in Molecular Epidemiology: Human Rhinovirus Prevalence and Genetics

    ERIC Educational Resources Information Center

    Albright, Catherine J.; Hall, David J.

    2011-01-01

    Human rhinovirus (HRV) is one of the most common human respiratory pathogens and is responsible for the majority of upper respiratory illnesses. Recently, a phylogeny was constructed from all known American Type Culture Collection (ATCC) HRV sequences. From this study, three HRV classifications (HRVA, HRVB, and HRVC) were determined and techniques…

  4. PRELIMINARY HEALTH BURDEN ANALYSIS FOR EPIDEMIOLOGIC RECREATIONAL WATER STUDY

    EPA Science Inventory

    Introduction: The National Epidemiological and Environmental Assessment of Recreational Water Study (NEEAR) offers a rare opportunity for researchers. The study's design involves the collection of health data before and after visiting the beach in conjunction with water quality...

  5. Triglyceride-Rich Lipoproteins and Atherosclerotic Cardiovascular Disease: New Insights From Epidemiology, Genetics, and Biology.

    PubMed

    Nordestgaard, Børge G

    2016-02-19

    Scientific interest in triglyceride-rich lipoproteins has fluctuated over the past many years, ranging from beliefs that these lipoproteins cause atherosclerotic cardiovascular disease (ASCVD) to being innocent bystanders. Correspondingly, clinical recommendations have fluctuated from a need to reduce levels to no advice on treatment. New insight in epidemiology now suggests that these lipoproteins, marked by high triglycerides, are strong and independent predictors of ASCVD and all-cause mortality, and that their cholesterol content or remnant cholesterol likewise are strong predictors of ASCVD. Of all adults, 27% have triglycerides >2 mmol/L (176 mg/dL), and 21% have remnant cholesterol >1 mmol/L (39 mg/dL). For individuals in the general population with nonfasting triglycerides of 6.6 mmol/L (580 mg/dL) compared with individuals with levels of 0.8 mmol/L (70 mg/dL), the risks were 5.1-fold for myocardial infarction, 3.2-fold for ischemic heart disease, 3.2-fold for ischemic stroke, and 2.2-fold for all-cause mortality. Also, genetic studies using the Mendelian randomization design, an approach that minimizes problems with confounding and reverse causation, now demonstrate that triglyceride-rich lipoproteins are causally associated with ASCVD and all-cause mortality. Finally, genetic evidence also demonstrates that high concentrations of triglyceride-rich lipoproteins are causally associated with low-grade inflammation. This suggests that an important part of inflammation in atherosclerosis and ASCVD is because of triglyceride-rich lipoprotein degradation and uptake into macrophage foam cells in the arterial intima. Taken together, new insights now strongly suggest that elevated triglyceride-rich lipoproteins represent causal risk factors for low-grade inflammation, ASCVD, and all-cause mortality. PMID:26892957

  6. Cartilage-hair hypoplasia in Finland: epidemiological and genetic aspects of 107 patients.

    PubMed

    Mäkitie, O

    1992-09-01

    Cartilage-hair hypoplasia (CHH) is an autosomal recessive form of metaphyseal chondrodysplasia characterised by short limbed short stature, hypoplastic hair growth, and impaired cell mediated immunity and erythrocyte production. The syndrome is exceptionally prevalent among the Finns and among the Old Order Amish in the United States; sporadic cases have been reported from other countries. An epidemiological and genetic study of CHH in Finland showed 107 patients, 46 males and 61 females, in 85 families. Eighteen of them had died, seven before the age of 1 year. The living patients ranged in age from 1 to 51 years, median 21 years. The incidence was estimated to be 1:23,000 live births. Consanguinity was found in two families and interfamilial relationships in 20 families. Geographical distribution of the birth places of the patients and their great grandparents showed accumulation in a small area in western Finland and regional clusters were seen in other parts of the country as well. The result of the segregation analysis was in accordance with recessive inheritance with reduced penetrance. PMID:1404295

  7. The genetics, epidemiology, and early detection of gastrointestinal cancers.

    PubMed

    Young, G P; Demediuk, B H

    1992-08-01

    Current recommendations for screening large populations for colorectal neoplasia have been promulgated by a number of researchers and authorities who generally agree that ongoing screening is justifiable in high-risk groups but not yet in average-risk groups. Nonetheless, it is thought to be justifiable to provide screening for average-risk individuals upon request. Choice of tools for screening remains under discussion. Colonoscopy is generally agreed to be justifiable in those patients with the highest risk, ie, members of families with a clear inherited tendency to develop colorectal cancer or those with a personal history of colorectal neoplasia. There is currently no agreement concerning the recommended tools for those with a weaker family history (one or two affected relatives), but regular fecal occult blood testing with occasional limited endoscopic examination of the bowel is usually favored. The new immunochemical-based occult blood tests show great promise for improved sensitivity and specificity. The evidence of the association between Helicobacter pylori gastritis and gastric cancer has been strengthened by three studies that show that patients with gastric cancer are more likely to have had infection in the years (up to 20) prior to diagnosis. The relative risk for cancer when infected with H. pylori is 3.6 to 6, but many H. pylori-positive individuals do not develop gastric cancer and additional factors must be operative. Probably the most exciting development for gastroenterology in 1991 is the identification of the gene on chromosome 5, designated APC, which is responsible for familial adenomatous polyposis.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1511028

  8. Epidemiology and evolution of the genetic variability of Anaplasma marginale in South Africa.

    PubMed

    Mutshembele, Awelani M; Cabezas-Cruz, Alejandro; Mtshali, Moses S; Thekisoe, Oriel M M; Galindo, Ruth C; de la Fuente, José

    2014-10-01

    Bovine anaplasmosis caused by infection of cattle with Anaplasma marginale has been considered to be endemic in South Africa, an assumption based primarily on the distribution of the tick vectors of A. marginale and serological studies on the prevalence of anaplasmosis in Limpopo, Free State, and North West. However, molecular evidence of the distribution of anaplasmosis has only been reported in the Free State province. In order to establish effective control measures for anaplasmosis, epidemiological surveys are needed to define the prevalence and distribution of A. marginale in South Africa. In addition, a proposed control strategy for anaplasmosis is the development of an A. marginale major surface protein 1a (MSP1a)-based vaccine. Nevertheless, regional variations of this gene would need to be characterized prior to vaccine development for South Africa. The objectives of the present study were therefore to conduct a national survey of the prevalence of A. marginale in South Africa, followed by an evaluation of the diversity and evolution of msp1a in South African strains of A. marginale. To accomplish these objectives, species-specific PCR was used to test 250 blood samples from cattle collected from all South African provinces (including 26 districts and municipalities), except the Free State province where similar studies were reported previously. The prevalence of A. marginale ranged from 65% to 100%, except in Northern Cape province where A. marginale was not detected. A correlation was found between the prevalence and genetic diversity of A. marginale MSP1a. Additionally, the genetic diversity of the A. marginale MSP1a was found to evolve under negative and positive selection, and 23 new tandem repeats in South Africa were shown to have evolved from the extant tandem repeat 4. Despite the MSP1a genetic variability, some types of tandem repeats were found to be conserved among the A. marginale strains, and low-variable peptides in MSP1a tandem repeats were

  9. Bat Rabies in France: A 24-Year Retrospective Epidemiological Study

    PubMed Central

    Picard-Meyer, Evelyne; Robardet, Emmanuelle; Arthur, Laurent; Larcher, Gérald; Harbusch, Christine; Servat, Alexandre; Cliquet, Florence

    2014-01-01

    Since bat rabies surveillance was first implemented in France in 1989, 48 autochthonous rabies cases without human contamination have been reported using routine diagnosis methods. In this retrospective study, data on bats submitted for rabies testing were analysed in order to better understand the epidemiology of EBLV-1 in bats in France and to investigate some epidemiological trends. Of the 3176 bats submitted for rabies diagnosis from 1989 to 2013, 1.96% (48/2447 analysed) were diagnosed positive. Among the twelve recognised virus species within the Lyssavirus genus, two species were isolated in France. 47 positive bats were morphologically identified as Eptesicus serotinus and were shown to be infected by both the EBLV-1a and the EBLV-1b lineages. Isolation of BBLV in Myotis nattereri was reported once in the north-east of France in 2012. The phylogenetic characterisation of all 47 French EBLV-1 isolates sampled between 1989 and 2013 and the French BBLV sample against 21 referenced partial nucleoprotein sequences confirmed the low genetic diversity of EBLV-1 despite its extensive geographical range. Statistical analysis performed on the serotine bat data collected from 1989 to 2013 showed seasonal variation of rabies occurrence with a significantly higher proportion of positive samples detected during the autumn compared to the spring and the summer period (34% of positive bats detected in autumn, 15% in summer, 13% in spring and 12% in winter). In this study, we have provided the details of the geographical distribution of EBLV-1a in the south-west of France and the north-south division of EBLV-1b with its subdivisions into three phylogenetic groups: group B1 in the north-west, group B2 in the centre and group B3 in the north-east of France. PMID:24892287

  10. [Epidemiological and clinical study of dental agenesis].

    PubMed

    Chimenti, C; Antenucci, F; Giannoni, M; Marci, M C; Santini, T

    1990-01-01

    This work realized thanks to exchange by IFMSA happened at Medical School Praga's invitation, describes two researchs. The first presents the casuistry of scholastic czechoslovak population; the second 87 cases with multiple teeth agenesis observed at Pedodontic's Clinical of Praga's Hospital Motol. The Authors, after describing the review of literature about epidemiology, etiopathogenetic, symptomatology and diagnosis aspects, present a personal contribution in accordance with existing literature.

  11. Genome-wide Association Studies from the Cancer Genetic Markers of Susceptibility (CGEMS) Initiative | Office of Cancer Genomics

    Cancer.gov

    CGEMS identifies common inherited genetic variations associated with a number of cancers, including breast and prostate. Data from these genome-wide association studies (GWAS) are available through the Division of Cancer Epidemiology & Genetics website.

  12. Epidemiological studies of plague in India

    PubMed Central

    Seal, S. C.

    1960-01-01

    Plague is apparently receding from India, but whether this recession heralds its final disappearance from the subcontinent or is merely a phase in its secular trend or is perhaps due to the effect of control measures is a matter for consideration. On the correct assessment of the present position will depend the nature of the steps to be taken now or in the future. Among the factors considered in this assessment are the possible existence of endemic plague foci in India, the clinical forms of the disease encountered, the relative frequency and epidemiology of urban and rural plague, seasonal variations in prevalence, and the likelihood of resistance of fleas to insecticides. PMID:14444324

  13. How to design a (good) epidemiological observational study: epidemiological research protocol at a glance.

    PubMed

    Fronteira, Ines

    2013-01-01

    In this article, we propose a general structure for designing a research protocol of an observational epidemiological study. We start by highlighting the importance of the research protocol, namely in accounting for some bias and guaranteeing methodologic rigor and study reproductability. Next, we reflect on some of the essential elements of a research protocol no matter its objective. We further present some specific issues to be included according to the type of study: cross-sectional, case-control and cohort.

  14. Brazilian studies on the genetics of Schistosoma mansoni

    PubMed Central

    Gentile, Rosana; Oliveira, Guilherme

    2009-01-01

    The parasite Schistosoma is known to exhibit variations among species, strains and genera, such as, the levels of infectivity, pathogenicity and immunogenicity. These factors may differ among parasite populations according to the local epidemiological conditions. Diversity observed in S. mansoni from different geographical regions or within individuals of the same region can be determined by differences in the genotype of each parasite strain. However, until recently, finding adequate genetic markers to investigate infectivity or other epidemiological characteristics of a transmission area proved difficult. Several studies have been conducted to evaluate the genetic variability of S. mansoni, using different techniques. Intraspecific variability was observed in morphological characters, isoenzyme studies, mtDNA, ribosomal gene probes, RAPD and microsatellites. The sequencing of the S. mansoni genome was the most important achievement concerning genetic approaches to the study of this parasite and may improve the development of drugs, vaccines and diagnostics of schistosomiasis. The knowledge of the genetic structure of schistosome populations in relation to epidemiological data and host variability is essential for the understanding of the epidemiology of the disease and the design of control strategies. PMID:18831955

  15. Global Dissemination of Carbapenemase-Producing Klebsiella pneumoniae: Epidemiology, Genetic Context, Treatment Options, and Detection Methods

    PubMed Central

    Lee, Chang-Ro; Lee, Jung Hun; Park, Kwang Seung; Kim, Young Bae; Jeong, Byeong Chul; Lee, Sang Hee

    2016-01-01

    The emergence of carbapenem-resistant Gram-negative pathogens poses a serious threat to public health worldwide. In particular, the increasing prevalence of carbapenem-resistant Klebsiella pneumoniae is a major source of concern. K. pneumoniae carbapenemases (KPCs) and carbapenemases of the oxacillinase-48 (OXA-48) type have been reported worldwide. New Delhi metallo-β-lactamase (NDM) carbapenemases were originally identified in Sweden in 2008 and have spread worldwide rapidly. In this review, we summarize the epidemiology of K. pneumoniae producing three carbapenemases (KPCs, NDMs, and OXA-48-like). Although the prevalence of each resistant strain varies geographically, K. pneumoniae producing KPCs, NDMs, and OXA-48-like carbapenemases have become rapidly disseminated. In addition, we used recently published molecular and genetic studies to analyze the mechanisms by which these three carbapenemases, and major K. pneumoniae clones, such as ST258 and ST11, have become globally prevalent. Because carbapenemase-producing K. pneumoniae are often resistant to most β-lactam antibiotics and many other non-β-lactam molecules, the therapeutic options available to treat infection with these strains are limited to colistin, polymyxin B, fosfomycin, tigecycline, and selected aminoglycosides. Although, combination therapy has been recommended for the treatment of severe carbapenemase-producing K. pneumoniae infections, the clinical evidence for this strategy is currently limited, and more accurate randomized controlled trials will be required to establish the most effective treatment regimen. Moreover, because rapid and accurate identification of the carbapenemase type found in K. pneumoniae may be difficult to achieve through phenotypic antibiotic susceptibility tests, novel molecular detection techniques are currently being developed. PMID:27379038

  16. Global Dissemination of Carbapenemase-Producing Klebsiella pneumoniae: Epidemiology, Genetic Context, Treatment Options, and Detection Methods.

    PubMed

    Lee, Chang-Ro; Lee, Jung Hun; Park, Kwang Seung; Kim, Young Bae; Jeong, Byeong Chul; Lee, Sang Hee

    2016-01-01

    The emergence of carbapenem-resistant Gram-negative pathogens poses a serious threat to public health worldwide. In particular, the increasing prevalence of carbapenem-resistant Klebsiella pneumoniae is a major source of concern. K. pneumoniae carbapenemases (KPCs) and carbapenemases of the oxacillinase-48 (OXA-48) type have been reported worldwide. New Delhi metallo-β-lactamase (NDM) carbapenemases were originally identified in Sweden in 2008 and have spread worldwide rapidly. In this review, we summarize the epidemiology of K. pneumoniae producing three carbapenemases (KPCs, NDMs, and OXA-48-like). Although the prevalence of each resistant strain varies geographically, K. pneumoniae producing KPCs, NDMs, and OXA-48-like carbapenemases have become rapidly disseminated. In addition, we used recently published molecular and genetic studies to analyze the mechanisms by which these three carbapenemases, and major K. pneumoniae clones, such as ST258 and ST11, have become globally prevalent. Because carbapenemase-producing K. pneumoniae are often resistant to most β-lactam antibiotics and many other non-β-lactam molecules, the therapeutic options available to treat infection with these strains are limited to colistin, polymyxin B, fosfomycin, tigecycline, and selected aminoglycosides. Although, combination therapy has been recommended for the treatment of severe carbapenemase-producing K. pneumoniae infections, the clinical evidence for this strategy is currently limited, and more accurate randomized controlled trials will be required to establish the most effective treatment regimen. Moreover, because rapid and accurate identification of the carbapenemase type found in K. pneumoniae may be difficult to achieve through phenotypic antibiotic susceptibility tests, novel molecular detection techniques are currently being developed. PMID:27379038

  17. Networks in Coronary Heart Disease Genetics As a Step towards Systems Epidemiology.

    PubMed

    Drenos, Fotios; Grossi, Enzo; Buscema, Massimo; Humphries, Steve E

    2015-01-01

    We present the use of innovative machine learning techniques in the understanding of Coronary Heart Disease (CHD) through intermediate traits, as an example of the use of this class of methods as a first step towards a systems epidemiology approach of complex diseases genetics. Using a sample of 252 middle-aged men, of which 102 had a CHD event in 10 years follow-up, we applied machine learning algorithms for the selection of CHD intermediate phenotypes, established markers, risk factors, and their previously associated genetic polymorphisms, and constructed a map of relationships between the selected variables. Of the 52 variables considered, 42 were retained after selection of the most informative variables for CHD. The constructed map suggests that most selected variables were related to CHD in a context dependent manner while only a small number of variables were related to a specific outcome. We also observed that loss of complexity in the network was linked to a future CHD event. We propose that novel, non-linear, and integrative epidemiological approaches are required to combine all available information, in order to truly translate the new advances in medical sciences to gains in preventive measures and patients care.

  18. Networks in Coronary Heart Disease Genetics As a Step towards Systems Epidemiology

    PubMed Central

    Drenos, Fotios; Grossi, Enzo; Buscema, Massimo; Humphries, Steve E.

    2015-01-01

    We present the use of innovative machine learning techniques in the understanding of Coronary Heart Disease (CHD) through intermediate traits, as an example of the use of this class of methods as a first step towards a systems epidemiology approach of complex diseases genetics. Using a sample of 252 middle-aged men, of which 102 had a CHD event in 10 years follow-up, we applied machine learning algorithms for the selection of CHD intermediate phenotypes, established markers, risk factors, and their previously associated genetic polymorphisms, and constructed a map of relationships between the selected variables. Of the 52 variables considered, 42 were retained after selection of the most informative variables for CHD. The constructed map suggests that most selected variables were related to CHD in a context dependent manner while only a small number of variables were related to a specific outcome. We also observed that loss of complexity in the network was linked to a future CHD event. We propose that novel, non-linear, and integrative epidemiological approaches are required to combine all available information, in order to truly translate the new advances in medical sciences to gains in preventive measures and patients care. PMID:25951190

  19. Field epidemiologic studies of populations exposed to waste dumps.

    PubMed

    Heath, C W

    1983-02-01

    Epidemiologic studies are required for assessing health risks related to toxic waste exposure. Since the settings in which such studies must be performed are extremely diverse, epidemiologic approaches must be versatile. For any particular study, three fundamental requirements are to assess what toxic materials are present, understand how human exposure may occur, and objectively measure possible biologic effects. In assessing links between exposure and disease, epidemiologists must be particularly aware of: expected disease frequencies in relation to the size of populations studied, implications of long or varied disease latencies for study design and competing causes of disease and associated confounding variables. These concepts are illustrated by discussion of epidemiologic studies related to the Love Canal toxic waste dump site in Niagara Falls, NY. PMID:6825633

  20. Epidemiological study air disaster in Amsterdam (ESADA): study design

    PubMed Central

    Slottje, Pauline; Huizink, Anja C; Twisk, Jos WR; Witteveen, Anke B; van der Ploeg, Henk M; Bramsen, Inge; Smidt, Nynke; Bijlsma, Joost A; Bouter, Lex M; van Mechelen, Willem; Smid, Tjabe

    2005-01-01

    Background In 1992, a cargo aircraft crashed into apartment buildings in Amsterdam, killing 43 victims and destroying 266 apartments. In the aftermath there were speculations about the cause of the crash, potential exposures to hazardous materials due to the disaster and the health consequences. Starting in 2000, the Epidemiological Study Air Disaster in Amsterdam (ESADA) aimed to assess the long-term health effects of occupational exposure to this disaster on professional assistance workers. Methods/Design Epidemiological study among all the exposed professional fire-fighters and police officers who performed disaster-related task(s), and hangar workers who sorted the wreckage of the aircraft, as well as reference groups of their non-exposed colleagues who did not perform any disaster-related tasks. The study took place, on average, 8.5 years after the disaster. Questionnaires were used to assess details on occupational exposure to the disaster. Health measures comprised laboratory assessments in urine, blood and saliva, as well as self-reported current health measures, including health-related quality of life, and various physical and psychological symptoms. Discussion In this paper we describe and discuss the design of the ESADA. The ESADA will provide additional scientific knowledge on the long-term health effects of technological disasters on professional workers. PMID:15921536

  1. Perspectives: Why Study Human Genetics?

    ERIC Educational Resources Information Center

    Childs, Barton

    1983-01-01

    Reasons for studying human genetics are discussed. These include philosophical reasons, reasons of health, and social reasons. While content, interpretation, and emphasis of human genetics study will vary depending upon schools, teachers, and developmental stages of students, it is suggested that teachers address these three domains. (Author/JN)

  2. Genetic studies of substance abuse.

    PubMed

    Vanyukov, M M; Tarter, R E

    2000-05-01

    Genetic studies of substance abuse indicate that variation in the risk for the disorder in the population is contributed by differences in both individual genotypes and environment. Recent developments in genetics raise the possibility of disentangling the complex system of genotype-environment interaction that determines the development of the individual behavioral phenotype. This paper reviews the concepts, methods and results pertaining to genetic investigation of substance abuse.

  3. Epidemiological Study of Greek University Students' Mental Health

    ERIC Educational Resources Information Center

    Kounenou, Kalliope; Koutra, Aikaterini; Katsiadrami, Aristea; Diacogiannis, Georgios

    2011-01-01

    In the present study, 805 Greek students participated by filling in self-report questionnaires studying depression (Center for Epidemiological Studies Depression Scale), general health status (General Health Questionnaire), general psychopathology (Symptom Checklist-90-R), and personal demographic features. Some of the more prevalent findings…

  4. Genetic and epidemiological insights into the emergence of peste des petits ruminants virus (PPRV) across Asia and Africa.

    PubMed

    Padhi, Abinash; Ma, Li

    2014-11-13

    Small ruminants are important components in the livelihood of millions of households in many parts of the world. The spread of the highly contagious peste des petits ruminants (PPR) disease, which is caused by an RNA virus, PPRV, across Asia and Africa remains a major concern. The present study explored the evolutionary and epidemiological dynamics of PPRV through the analyses of partial N-gene and F-gene sequences of the virus. All the four previously described PPRV lineages (I-IV) diverged from their common ancestor during the late-19(th) to early-20(th) century. Among the four lineages, PPRV-IV showed pronounced genetic structuring across the region; however, haplotype sharing among the geographic regions, together with the presence of multiple genetic clusters within a country, indicates the possibility of frequent mobility of the diseased individuals across the region. The gradual decline in the effective number of infections suggests a limited genetic variation, which could be attributed to the effective vaccination that has been practiced since 1990s. However, the movement of infected animals across the region likely contributes to the spread of PPRV-IV. No evidence of positive selection was identified from this study.

  5. Genetic and epidemiological insights into the emergence of peste des petits ruminants virus (PPRV) across Asia and Africa.

    PubMed

    Padhi, Abinash; Ma, Li

    2014-01-01

    Small ruminants are important components in the livelihood of millions of households in many parts of the world. The spread of the highly contagious peste des petits ruminants (PPR) disease, which is caused by an RNA virus, PPRV, across Asia and Africa remains a major concern. The present study explored the evolutionary and epidemiological dynamics of PPRV through the analyses of partial N-gene and F-gene sequences of the virus. All the four previously described PPRV lineages (I-IV) diverged from their common ancestor during the late-19(th) to early-20(th) century. Among the four lineages, PPRV-IV showed pronounced genetic structuring across the region; however, haplotype sharing among the geographic regions, together with the presence of multiple genetic clusters within a country, indicates the possibility of frequent mobility of the diseased individuals across the region. The gradual decline in the effective number of infections suggests a limited genetic variation, which could be attributed to the effective vaccination that has been practiced since 1990s. However, the movement of infected animals across the region likely contributes to the spread of PPRV-IV. No evidence of positive selection was identified from this study. PMID:25391314

  6. New Insights into the Molecular Epidemiology and Population Genetics of Schistosoma mansoni in Ugandan Pre-school Children and Mothers

    PubMed Central

    Betson, Martha; Sousa-Figueiredo, Jose C.; Kabatereine, Narcis B.; Stothard, J. Russell

    2013-01-01

    Significant numbers of pre-school children are infected with Schistosoma mansoni in sub-Saharan Africa and are likely to play a role in parasite transmission. However, they are currently excluded from control programmes. Molecular phylogenetic studies have provided insights into the evolutionary origins and transmission dynamics of S. mansoni, but there has been no research into schistosome molecular epidemiology in pre-school children. Here, we investigated the genetic diversity and population structure of S. mansoni in pre-school children and mothers living in lakeshore communities in Uganda and monitored for changes over time after praziquantel treatment. Parasites were sampled from children (<6 years) and mothers enrolled in the longitudinal Schistosomiasis Mothers and Infants Study at baseline and at 6-, 12- and 18-month follow-up surveys. 1347 parasites from 35 mothers and 45 children were genotyped by direct sequencing of the cytochrome c oxidase (cox1) gene. The cox1 region was highly diverse with over 230 unique sequences identified. Parasite populations were genetically differentiated between lakes and non-synonymous mutations were more diverse at Lake Victoria than Lake Albert. Surprisingly, parasite populations sampled from children showed a similar genetic diversity to those sampled from mothers, pointing towards a non-linear relationship between duration of exposure and accumulation of parasite diversity. The genetic diversity six months after praziquantel treatment was similar to pre-treatment diversity. Our results confirm the substantial genetic diversity of S. mansoni in East Africa and provide significant insights into transmission dynamics within young children and mothers, important information for schistosomiasis control programmes. PMID:24349589

  7. Field synopsis and meta-analyses of genetic epidemiological evidence for Kashin-Beck disease, an endemic osteoarthropathy in China.

    PubMed

    Yang, Lei; Zhao, Guang-Hui; Liu, Huan; Wang, Xi; Guo, Xiong; Lammi, Mikko J

    2016-10-01

    Kashin-Beck disease (KBD) is a chronic degenerative osteoarthropathy with unclear etiology. To provide current evidence supporting a genetic predisposition for KBD, we conducted a systematic review and meta-analysis of published literature on the genetic epidemiology of KBD. The PubMed, China National Knowledge Infrastructure and Wan Fang Data were searched up to August 2015 for articles published in English and Chinese. Genome-wide and exome sequencing, linkage, and case-control association studies for any genetic variants associated with KBD were included. Meta-analysis was performed for all single nucleotide polymorphisms (SNPs) that were evaluated in two or more studies. The effect size was summarized as odds ratios (ORs) with 95 % confidence intervals (CIs) by fixed and random effects models. A total of 24 articles were systematically reviewed. Eleven short tandem repeats on chromosomes 2, 11 and 12, 34 SNPs in 12 genes, as well as copy number variant 452 were identified as KBD susceptibility factors in individual studies. The meta-analysis of the GPX1 rs1050450, DIO2 rs225014, TrxR2 rs5748469 and HLA-DRB1 rs7745040 failed to reveal any associations with KBD. However, the meta-analysis of HLA-DRB1 rs9275295 allele A was associated with KBD (OR = 1.737, 95 % CI: 1.002-3.012). In addition, seven haplotypes in GPX1, GPX4, HLA-DRB1 and GDF5 genes also showed significant associations with KBD. In conclusions, our study could identify a number of genetic markers associated with KBD. However, the evidence does not currently support a strong association between the specific variants and KBD because of the limited number of studies, and in the future, more rigorous studies are needed to confirm KBD's links with these variants. PMID:27256326

  8. Molecular Epidemiology of Novel Pathogen “Brachyspira hampsonii” Reveals Relationships between Diverse Genetic Groups, Regions, Host Species, and Other Pathogenic and Commensal Brachyspira Species

    PubMed Central

    Mirajkar, Nandita S.; Bekele, Aschalew Z.; Chander, Yogesh Y.

    2015-01-01

    Outbreaks of bloody diarrhea in swine herds in the late 2000s signaled the reemergence of an economically significant disease, swine dysentery, in the United States. Investigations confirmed the emergence of a novel spirochete in swine, provisionally designated “Brachyspira hampsonii,” with two genetically distinct clades. Although it has since been detected in swine and migratory birds in Europe and North America, little is known about its genetic diversity or its relationships with other Brachyspira species. This study characterizes B. hampsonii using a newly developed multilocus sequence typing (MLST) approach and elucidates the diversity, distribution, population structure, and genetic relationships of this pathogen from diverse epidemiological sources globally. Genetic characterization of 81 B. hampsonii isolates, originating from six countries, with our newly established MLST scheme identified a total of 20 sequence types (STs) belonging to three clonal complexes (CCs). B. hampsonii showed a heterogeneous population structure with evidence of microevolution locally in swine production systems, while its clustering patterns showed associations with its epidemiological origins (country, swine production system, and host species). The close genetic relatedness of B. hampsonii isolates from different countries and host species highlights the importance of strict biosecurity control measures. A comparative analysis of 430 isolates representing seven Brachyspira species (pathogens and commensals) from 19 countries and 10 host species depicted clustering by microbial species. It revealed the close genetic relatedness of B. hampsonii with commensal Brachyspira species and also provided support for the two clades of B. hampsonii to be considered a single species. PMID:26135863

  9. Overview of risk assessment in new EPA epidemiology studies

    EPA Science Inventory

    Since 2003, the Office of Research and Development of the US Environmental Protection Agency has conducted a series of epidemiology studies of water quality and health effects among beach goers at beaches across the United States. These studies are designed to establish associati...

  10. Peyronie’s disease: a literature review on epidemiology, genetics, pathophysiology, diagnosis and work-up

    PubMed Central

    Al-Thakafi, Sultan

    2016-01-01

    Peyronie’s disease (PD), a fibromatous disorder of the tunica albuginea of the penile corpus cavernosum, named after the French physician Francois de la Peyronie, is characterized by pain, plaque formation, penile curvature, and plaque calcification. The epidemiological data on PD is inconsistent, with recent reports stating a prevalence of up to 9%, and the condition affecting men of all ages, from teenagers to septuagenarians. We are just beginning to elucidate the role of genetics as a causative factor for PD. Chromosomal abnormalities and single-nucleotide polymorphisms have been shown to be associated with fibrotic diatheses. Tunical mechanical stress and microvascular trauma are major contributory factors to the pathophysiology of PD. The diagnosis of PD can be made using a combination of clinical history, physical examination and, sometimes, imaging modalities. A better understanding of the molecular pathophysiology of this condition remains paramount for the development of newer and more effective disease-targeted interventions. PMID:27298774

  11. Molecular Epidemiology of Foodborne Pathogens

    NASA Astrophysics Data System (ADS)

    Chen, Yi; Brown, Eric; Knabel, Stephen J.

    The purpose of this chapter is to describe the basic principles and advancements in the molecular epidemiology of foodborne pathogens. Epidemiology is the study of the distribution and determinants of infectious diseases and/or the dynamics of disease transmission. The goals of epidemiology include the identification of physical sources, routes of transmission of infectious agents, and distribution and relationships of different subgroups. Molecular epidemiology is the study of epidemiology at the molecular level. It has been defined as "a science that focuses on the contribution of potential genetic and environmental risk factors, identified at the molecular level, to the etiology, distribution and prevention of diseases within families and across populations".

  12. Molecular and epidemiological studies of Porcine rubulavirus infection - an overview.

    PubMed

    Cuevas-Romero, Julieta Sandra; Blomström, Anne-Lie; Berg, Mikael

    2015-01-01

    Porcine rubulavirus-La Piedad-Michoacan-Mexico virus (PorPV-LPMV) was identified as the causative agent of a viral disease that emerged spontaneously in Mexican swine in the 1980s. Since the report of the initial outbreak of the disease, only one full-length genome from a strain isolated in 1984 (PorPV-LPMV/1984) has been sequenced; sequence data are scarce from other isolates. The genetic variation of this virus that has spread throughout the main endemic region of Mexico is almost a complete mystery. The development of molecular techniques for improved diagnostics and to investigate the persistence, molecular epidemiology, and the possible reservoirs of PorPV are needed. Together, this will provide greater knowledge regarding the molecular genetic changes and useful data to establish new strategies in the control of this virus in Mexico.

  13. Overview of epidemiology, genetics, birth defects, and chromosome abnormalities associated with CDH.

    PubMed

    Pober, Barbara R

    2007-05-15

    Congenital diaphragmatic hernia (CDH) is a common and well-studied birth defect. The etiology of most cases remains unknown but increasing evidence points to genetic causation. The data supporting genetic etiologies which are detailed below include the association of CDH with recurring chromosome abnormalities, the existence of CDH-multiplex families, and the co-occurrence of CDH with additional congenital malformations.

  14. Sample size calculation for meta-epidemiological studies.

    PubMed

    Giraudeau, Bruno; Higgins, Julian P T; Tavernier, Elsa; Trinquart, Ludovic

    2016-01-30

    Meta-epidemiological studies are used to compare treatment effect estimates between randomized clinical trials with and without a characteristic of interest. To our knowledge, there is presently nothing to help researchers to a priori specify the required number of meta-analyses to be included in a meta-epidemiological study. We derived a theoretical power function and sample size formula in the framework of a hierarchical model that allows for variation in the impact of the characteristic between trials within a meta-analysis and between meta-analyses. A simulation study revealed that the theoretical function overestimated power (because of the assumption of equal weights for each trial within and between meta-analyses). We also propose a simulation approach that allows for relaxing the constraints used in the theoretical approach and is more accurate. We illustrate that the two variables that mostly influence power are the number of trials per meta-analysis and the proportion of trials with the characteristic of interest. We derived a closed-form power function and sample size formula for estimating the impact of trial characteristics in meta-epidemiological studies. Our analytical results can be used as a 'rule of thumb' for sample size calculation for a meta-epidemiologic study. A more accurate sample size can be derived with a simulation study.

  15. Genetic and Molecular Epidemiological Characterization of a Novel Adenovirus in Antarctic Penguins Collected between 2008 and 2013

    PubMed Central

    Lee, Sook-Young; Kim, Jeong-Hoon; Seo, Tae-Kun; No, Jin Sun; Kim, Hankyeom; Kim, Won-keun; Choi, Han-Gu; Kang, Sung-Ho; Song, Jin-Won

    2016-01-01

    Antarctica is considered a relatively uncontaminated region with regard to the infectious diseases because of its extreme environment, and isolated geography. For the genetic characterization and molecular epidemiology of the newly found penguin adenovirus in Antarctica, entire genome sequencing and annual survey of penguin adenovirus were conducted. The entire genome sequences of penguin adenoviruses were completed for two Chinstrap penguins (Pygoscelis antarctica) and two Gentoo penguins (Pygoscelis papua). The whole genome lengths and G+C content of penguin adenoviruses were found to be 24,630–24,662 bp and 35.5–35.6%, respectively. Notably, the presence of putative sialidase gene was not identified in penguin adenoviruses by Rapid Amplification of cDNA Ends (RACE-PCR) as well as consensus specific PCR. The penguin adenoviruses were demonstrated to be a new species within the genus Siadenovirus, with a distance of 29.9–39.3% (amino acid, 32.1–47.9%) in DNA polymerase gene, and showed the closest relationship with turkey adenovirus 3 (TAdV-3) in phylogenetic analysis. During the 2008–2013 study period, the penguin adenoviruses were annually detected in 22 of 78 penguins (28.2%), and the molecular epidemiological study of the penguin adenovirus indicates a predominant infection in Chinstrap penguin population (12/30, 40%). Interestingly, the genome of penguin adenovirus could be detected in several internal samples, except the lymph node and brain. In conclusion, an analysis of the entire adenoviral genomes from Antarctic penguins was conducted, and the penguin adenoviruses, containing unique genetic character, were identified as a new species within the genus Siadenovirus. Moreover, it was annually detected in Antarctic penguins, suggesting its circulation within the penguin population. PMID:27309961

  16. Genetic and Molecular Epidemiological Characterization of a Novel Adenovirus in Antarctic Penguins Collected between 2008 and 2013.

    PubMed

    Lee, Sook-Young; Kim, Jeong-Hoon; Seo, Tae-Kun; No, Jin Sun; Kim, Hankyeom; Kim, Won-Keun; Choi, Han-Gu; Kang, Sung-Ho; Song, Jin-Won

    2016-01-01

    Antarctica is considered a relatively uncontaminated region with regard to the infectious diseases because of its extreme environment, and isolated geography. For the genetic characterization and molecular epidemiology of the newly found penguin adenovirus in Antarctica, entire genome sequencing and annual survey of penguin adenovirus were conducted. The entire genome sequences of penguin adenoviruses were completed for two Chinstrap penguins (Pygoscelis antarctica) and two Gentoo penguins (Pygoscelis papua). The whole genome lengths and G+C content of penguin adenoviruses were found to be 24,630-24,662 bp and 35.5-35.6%, respectively. Notably, the presence of putative sialidase gene was not identified in penguin adenoviruses by Rapid Amplification of cDNA Ends (RACE-PCR) as well as consensus specific PCR. The penguin adenoviruses were demonstrated to be a new species within the genus Siadenovirus, with a distance of 29.9-39.3% (amino acid, 32.1-47.9%) in DNA polymerase gene, and showed the closest relationship with turkey adenovirus 3 (TAdV-3) in phylogenetic analysis. During the 2008-2013 study period, the penguin adenoviruses were annually detected in 22 of 78 penguins (28.2%), and the molecular epidemiological study of the penguin adenovirus indicates a predominant infection in Chinstrap penguin population (12/30, 40%). Interestingly, the genome of penguin adenovirus could be detected in several internal samples, except the lymph node and brain. In conclusion, an analysis of the entire adenoviral genomes from Antarctic penguins was conducted, and the penguin adenoviruses, containing unique genetic character, were identified as a new species within the genus Siadenovirus. Moreover, it was annually detected in Antarctic penguins, suggesting its circulation within the penguin population. PMID:27309961

  17. Epidemiological Study on the Involvements of Environmental Factors and Allergy in Child Mental Health Using the Autism Screening Questionnaire

    ERIC Educational Resources Information Center

    Shibata, Aki; Hitomi, Yoshiaki; Kambayashi, Yasuhiro; Hibino, Yuri; Yamazaki, Masami; Mitoma, Junko; Asakura, Hiroki; Hayashi, Koichi; Otaki, Naoto; Sagara, Takiko; Nakamura, Hiroyuki

    2013-01-01

    Although autism is now recognized as being very common (Buie et al., 2010) and as developing due to not only genetic but also environmental factors, there is insufficient epidemiological evidence on the relationship between autism and allergy. In this study, therefore, we attempted to clarify the association of environmental factors with autism…

  18. International Biological Engagement Programs Facilitate Newcastle Disease Epidemiological Studies

    PubMed Central

    Miller, Patti J.; Dimitrov, Kiril M.; Williams-Coplin, Dawn; Peterson, Melanie P.; Pantin-Jackwood, Mary J.; Swayne, David E.; Suarez, David L.; Afonso, Claudio L.

    2015-01-01

    Infections of poultry species with virulent strains of Newcastle disease virus (NDV) cause Newcastle disease (ND), one of the most economically significant and devastating diseases for poultry producers worldwide. Biological engagement programs between the Southeast Poultry Research Laboratory (SEPRL) of the United States Department of Agriculture and laboratories from Russia, Pakistan, Ukraine, Kazakhstan, and Indonesia collectively have produced a better understanding of the genetic diversity and evolution of the viruses responsible for ND, which is crucial for the control of the disease. The data from Kazakhstan, Russia, and Ukraine identified possible migratory routes for birds that may carry both virulent NDV (vNDV) and NDV of low virulence into Europe. In addition, related NDV strains were isolated from wild birds in Ukraine and Nigeria, and from birds in continental USA, Alaska, Russia, and Japan, identifying wild birds as a possible mechanism of intercontinental spread of NDV of low virulence. More recently, the detection of new sub-genotypes of vNDV suggests that a new, fifth, panzootic of ND has already originated in Southeast Asia, extended to the Middle East, and is now entering into Eastern Europe. Despite expected challenges when multiple independent laboratories interact, many scientists from the collaborating countries have successfully been trained by SEPRL on molecular diagnostics, best laboratory practices, and critical biosecurity protocols, providing our partners the capacity to further train other employes and to identify locally the viruses that cause this OIE listed disease. These and other collaborations with partners in Mexico, Bulgaria, Israel, and Tanzania have allowed SEPRL scientists to engage in field studies, to elucidate more aspects of ND epidemiology in endemic countries, and to understand the challenges that the scientists and field veterinarians in these countries face on a daily basis. Finally, new viral characterization tools

  19. International Biological Engagement Programs Facilitate Newcastle Disease Epidemiological Studies.

    PubMed

    Miller, Patti J; Dimitrov, Kiril M; Williams-Coplin, Dawn; Peterson, Melanie P; Pantin-Jackwood, Mary J; Swayne, David E; Suarez, David L; Afonso, Claudio L

    2015-01-01

    Infections of poultry species with virulent strains of Newcastle disease virus (NDV) cause Newcastle disease (ND), one of the most economically significant and devastating diseases for poultry producers worldwide. Biological engagement programs between the Southeast Poultry Research Laboratory (SEPRL) of the United States Department of Agriculture and laboratories from Russia, Pakistan, Ukraine, Kazakhstan, and Indonesia collectively have produced a better understanding of the genetic diversity and evolution of the viruses responsible for ND, which is crucial for the control of the disease. The data from Kazakhstan, Russia, and Ukraine identified possible migratory routes for birds that may carry both virulent NDV (vNDV) and NDV of low virulence into Europe. In addition, related NDV strains were isolated from wild birds in Ukraine and Nigeria, and from birds in continental USA, Alaska, Russia, and Japan, identifying wild birds as a possible mechanism of intercontinental spread of NDV of low virulence. More recently, the detection of new sub-genotypes of vNDV suggests that a new, fifth, panzootic of ND has already originated in Southeast Asia, extended to the Middle East, and is now entering into Eastern Europe. Despite expected challenges when multiple independent laboratories interact, many scientists from the collaborating countries have successfully been trained by SEPRL on molecular diagnostics, best laboratory practices, and critical biosecurity protocols, providing our partners the capacity to further train other employes and to identify locally the viruses that cause this OIE listed disease. These and other collaborations with partners in Mexico, Bulgaria, Israel, and Tanzania have allowed SEPRL scientists to engage in field studies, to elucidate more aspects of ND epidemiology in endemic countries, and to understand the challenges that the scientists and field veterinarians in these countries face on a daily basis. Finally, new viral characterization tools

  20. Schizophrenia, genetic retrenchment, and epidemiologic renaissance. The Sixth Biennial Winter Workshop on Schizophrenia, Badgastein, Austria, January 26-February 1, 1992.

    PubMed

    Waddington, J L; Weller, M P; Crow, T J; Hirsch, S R

    1992-12-01

    A distinctive feature of these workshops, in addition to those noted in the introductory overview, is the selection of a relatively isolated location for a 1-week period. This, together with a rich and varied program and an ethos of informality, encourages participants to discuss not only the work presented but also their unpublished work and their intuitions based on preliminary data and analyses. Such an interchange is of inestimable value to the schizophrenia research community. In scientific terms, a panel of concluding discussants (Drs Kendell, Torrey, and Waddington) were in some measure of agreement that genetics, particularly molecular genetics, appears to be experiencing a period of retrenchment, while epidemiology is experiencing something of a renaissance. Maternal influenza was a prominent theme, although the data were far from consistent. It was argued by Dr Wessely that risk for schizophrenia putatively attributable to maternal influenza might be 5% to 10% of all cases, indicating a modest effect. Eclectically, Dr Kendell believed the effect to be "real" but slight and fragile, it being sought against large aggregates that almost inevitably result in differing findings from differing countries or from different data bases within a given country. Gender differences were also among the more prominent themes, not just in an epidemiologic context but also in a variety of other studies. This points anew to disturbances in schizophrenia of factors that regulate, or are intimately associated with, sexual dimorphism in brain development. Abnormalities in cerebral asymmetry continue to pervade a variety of research findings and point further to neurodevelopmental anomalies.(ABSTRACT TRUNCATED AT 250 WORDS)

  1. Schizophrenia, genetic retrenchment, and epidemiologic renaissance. The Sixth Biennial Winter Workshop on Schizophrenia, Badgastein, Austria, January 26-February 1, 1992.

    PubMed

    Waddington, J L; Weller, M P; Crow, T J; Hirsch, S R

    1992-12-01

    A distinctive feature of these workshops, in addition to those noted in the introductory overview, is the selection of a relatively isolated location for a 1-week period. This, together with a rich and varied program and an ethos of informality, encourages participants to discuss not only the work presented but also their unpublished work and their intuitions based on preliminary data and analyses. Such an interchange is of inestimable value to the schizophrenia research community. In scientific terms, a panel of concluding discussants (Drs Kendell, Torrey, and Waddington) were in some measure of agreement that genetics, particularly molecular genetics, appears to be experiencing a period of retrenchment, while epidemiology is experiencing something of a renaissance. Maternal influenza was a prominent theme, although the data were far from consistent. It was argued by Dr Wessely that risk for schizophrenia putatively attributable to maternal influenza might be 5% to 10% of all cases, indicating a modest effect. Eclectically, Dr Kendell believed the effect to be "real" but slight and fragile, it being sought against large aggregates that almost inevitably result in differing findings from differing countries or from different data bases within a given country. Gender differences were also among the more prominent themes, not just in an epidemiologic context but also in a variety of other studies. This points anew to disturbances in schizophrenia of factors that regulate, or are intimately associated with, sexual dimorphism in brain development. Abnormalities in cerebral asymmetry continue to pervade a variety of research findings and point further to neurodevelopmental anomalies.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1360201

  2. The use of genomic DNA fingerprinting in studies of the epidemiology of bacteria in periodontitis.

    PubMed

    Genco, R J; Loos, B G

    1991-07-01

    Recent studies of microbial epidemiology emphasizing the genetic organization and distribution of organisms associated with orofacial infections have led to new insights into the possible origins of pathogenicity. Studies into genetic heterogeneity, acquisition and transmission of these organisms have been markedly advanced by the utilization of the powerful technique of genomic DNA fingerprinting. Characteristic fingerprints for each bacterial isolate can be produced by cleavage of high molecular weight genomic DNA by restriction endonucleases. It is assumed that each DNA fingerprint represents a clonal type. In this report, we review and analyze studies of the epidemiology of bacteria associated with orofacial infections with an emphasis on periodontal disease. Studies of nontypable (NT) Haemophilus influenzae associated with recurrent otitis media illustrate the utility of this technique. DNA fingerprinting clearly demonstrates genetic heterogeneity of NT H. influenzae isolates, and clonality of infection of any individual. Furthermore, DNA fingerprinting has shown that the same clonal type is seen in siblings concurrently suffering from otitis media, suggesting horizontal transmission within the family. Studies of mutans Streptococci also show extensive genetic heterogeneity and show vertical transmission of a predominant clonal type only from mother to infant, but not from father to infant. Studies of Actinobacillus actinomycetemcomitans show considerable genetic heterogeneity among monkey isolates. Thus far, three clonal types have been reported with DNA fingerprinting among isolates from periodontal patients, but additional genetic heterogeneity can be found using specific DNA fragments as probes in hybridization experiments. Intrafamilial transmission of A. actinomycetemcomitans has been demonstrated. Porphyromonas (Bacteroides) gingivalis shows extensive genetic heterogeneity and case reports suggest clonal infection of any one individual. In contrast

  3. Epidemiological and genetic clues for molecular mechanisms involved in uterine leiomyoma development and growth

    PubMed Central

    Commandeur, Arno E.; Styer, Aaron K.; Teixeira, Jose M.

    2015-01-01

    BACKGROUND Uterine leiomyomas (fibroids) are highly prevalent benign smooth muscle tumors of the uterus. In the USA, the lifetime risk for women developing uterine leiomyomas is estimated as up to 75%. Except for hysterectomy, most therapies or treatments often provide only partial or temporary relief and are not successful in every patient. There is a clear racial disparity in the disease; African-American women are estimated to be three times more likely to develop uterine leiomyomas and generally develop more severe symptoms. There is also familial clustering between first-degree relatives and twins, and multiple inherited syndromes in which fibroid development occurs. Leiomyomas have been described as clonal and hormonally regulated, but despite the healthcare burden imposed by the disease, the etiology of uterine leiomyomas remains largely unknown. The mechanisms involved in their growth are also essentially unknown, which has contributed to the slow progress in development of effective treatment options. METHODS A comprehensive PubMed search for and critical assessment of articles related to the epidemiological, biological and genetic clues for uterine leiomyoma development was performed. The individual functions of some of the best candidate genes are explained to provide more insight into their biological function and to interconnect and organize genes and pathways in one overarching figure that represents the current state of knowledge about uterine leiomyoma development and growth. RESULTS In this review, the widely recognized roles of estrogen and progesterone in uterine leiomyoma pathobiology on the basis of clinical and experimental data are presented. This is followed by fundamental aspects and concepts including the possible cellular origin of uterine fibroids. The central themes in the subsequent parts are cytogenetic aberrations in leiomyomas and the racial/ethnic disparities in uterine fibroid biology. Then, the attributes of various in vitro and

  4. Spinocerebellar ataxias in Venezuela: genetic epidemiology and their most likely ethnic descent.

    PubMed

    Paradisi, Irene; Ikonomu, Vassiliki; Arias, Sergio

    2016-03-01

    Dominantly inherited ataxias (spinocerebellar ataxias, SCAs) are a genetically heterogeneous group of neurologic diseases characterized by progressive cerebellar and spinal tract degeneration with ataxia and other signs, common to all known subtypes. Several types are relatively frequent worldwide, but in several countries, one specific SCA may show a higher prevalence owing to founder phenomena. In Venezuela, genetic epidemiological features of SCAs have been assessed during the last 30 years; mutations in ATXN1 (SCA1), ATXN2 (SCA2), ATXN3 (SCA3), CACNA1A (SCA6), ATXN7 (SCA7), ATXN8 (SCA8), ATXN10 (SCA10), TBP (SCA17) and ATN1 (dentatorubral pallidoluysian atrophy, DRPLA) loci were searched among 115 independent families. SCA7 was the most frequent subtype (26.6%), followed by SCA3 (25.0%), SCA2 (21.9%), SCA1 (17.2%), SCA10 (4.7%) and DRPLA (3.1%); in 43% of the families, the subtype remained unidentified. SCA7 mutations displayed strong geographic aggregation in two independent founder foci, and SCA1 showed a very remote founder effect for a subset of families. SCA10 families were scattered across the country, but all had an identical in-phase haplotype carried also by Mexican, Brazilian and Sioux patients, supporting a very old common Amerindian origin. Prevalence for dominant SCAs in Venezuela was estimated as 1:25 000 nuclear families, provenances of which are either Caucasoid, African or Amerindian.

  5. Spinocerebellar ataxias in Venezuela: genetic epidemiology and their most likely ethnic descent.

    PubMed

    Paradisi, Irene; Ikonomu, Vassiliki; Arias, Sergio

    2016-03-01

    Dominantly inherited ataxias (spinocerebellar ataxias, SCAs) are a genetically heterogeneous group of neurologic diseases characterized by progressive cerebellar and spinal tract degeneration with ataxia and other signs, common to all known subtypes. Several types are relatively frequent worldwide, but in several countries, one specific SCA may show a higher prevalence owing to founder phenomena. In Venezuela, genetic epidemiological features of SCAs have been assessed during the last 30 years; mutations in ATXN1 (SCA1), ATXN2 (SCA2), ATXN3 (SCA3), CACNA1A (SCA6), ATXN7 (SCA7), ATXN8 (SCA8), ATXN10 (SCA10), TBP (SCA17) and ATN1 (dentatorubral pallidoluysian atrophy, DRPLA) loci were searched among 115 independent families. SCA7 was the most frequent subtype (26.6%), followed by SCA3 (25.0%), SCA2 (21.9%), SCA1 (17.2%), SCA10 (4.7%) and DRPLA (3.1%); in 43% of the families, the subtype remained unidentified. SCA7 mutations displayed strong geographic aggregation in two independent founder foci, and SCA1 showed a very remote founder effect for a subset of families. SCA10 families were scattered across the country, but all had an identical in-phase haplotype carried also by Mexican, Brazilian and Sioux patients, supporting a very old common Amerindian origin. Prevalence for dominant SCAs in Venezuela was estimated as 1:25 000 nuclear families, provenances of which are either Caucasoid, African or Amerindian. PMID:26538302

  6. A nationwide epidemiological study of testicular torsion in Korea.

    PubMed

    Lee, Sol Min; Huh, Jung-Sik; Baek, Minki; Yoo, Koo Han; Min, Gyeong Eun; Lee, Hyung-Lae; Lee, Dong-Gi

    2014-12-01

    Testicular torsion is a surgical emergency in the field of urology. Knowledge of the epidemiology and pathophysiology is significant to an urologist. However, the epidemiology of testicular torsion in Korea has not been studied. We performed a nationwide epidemiological study to improve knowledge of the epidemiology of testicular torsion. From 2006-2011, the Korean Urologic Association began the patient registry service. The annual number of patients with testicular torsion from 2006 to 2011 were 225, 250, 271, 277, 345, and 210, respectively. The overall incidence of testicular torsion in males was 1.1 per 100,000; However, the incidence in men less than 25 yr old was 2.9 per 100,000. Adolescents showed the highest incidence. Total testicular salvage rate was 75.7% in this survey. There was no geographic difference of testicular salvage rate. Minimizing the possibility of orchiectomy for testicular torsion is important to improve public awareness to expedite presentation and provider education to improve diagnosis and surgery. PMID:25469070

  7. A nationwide epidemiological study of testicular torsion in Korea.

    PubMed

    Lee, Sol Min; Huh, Jung-Sik; Baek, Minki; Yoo, Koo Han; Min, Gyeong Eun; Lee, Hyung-Lae; Lee, Dong-Gi

    2014-12-01

    Testicular torsion is a surgical emergency in the field of urology. Knowledge of the epidemiology and pathophysiology is significant to an urologist. However, the epidemiology of testicular torsion in Korea has not been studied. We performed a nationwide epidemiological study to improve knowledge of the epidemiology of testicular torsion. From 2006-2011, the Korean Urologic Association began the patient registry service. The annual number of patients with testicular torsion from 2006 to 2011 were 225, 250, 271, 277, 345, and 210, respectively. The overall incidence of testicular torsion in males was 1.1 per 100,000; However, the incidence in men less than 25 yr old was 2.9 per 100,000. Adolescents showed the highest incidence. Total testicular salvage rate was 75.7% in this survey. There was no geographic difference of testicular salvage rate. Minimizing the possibility of orchiectomy for testicular torsion is important to improve public awareness to expedite presentation and provider education to improve diagnosis and surgery.

  8. [Ecological studies in environmental health: Beyond epidemiology].

    PubMed

    Blanco-Becerra, Luis C; Pinzón-Flórez, Carlos E; Idrovo, Álvaro J

    2015-08-01

    Ecological studies provide important and frequent sources of evidence of environmental health, since their unit of analysis is populations. This review summarizes the foundations of ecological studies with the premise that they can be performed using quantitative, qualitative or mixed methods. It presents the logic behind their design, their role in exploring causality, the variables and categories of analysis and the design principles and techniques used to collect data. Examples of ecological studies performed in Latin America are then presented, as well as some common methodological problems and options to address them. Lastly, the relevance of quantitative and qualitative ecological studies to environmental health as a way to overcome the dominance of conceptual and methodological individualism is highlighted, though ecological studies alone do not suffice for studying population health.

  9. [Ecological studies in environmental health: Beyond epidemiology].

    PubMed

    Blanco-Becerra, Luis C; Pinzón-Flórez, Carlos E; Idrovo, Álvaro J

    2015-08-01

    Ecological studies provide important and frequent sources of evidence of environmental health, since their unit of analysis is populations. This review summarizes the foundations of ecological studies with the premise that they can be performed using quantitative, qualitative or mixed methods. It presents the logic behind their design, their role in exploring causality, the variables and categories of analysis and the design principles and techniques used to collect data. Examples of ecological studies performed in Latin America are then presented, as well as some common methodological problems and options to address them. Lastly, the relevance of quantitative and qualitative ecological studies to environmental health as a way to overcome the dominance of conceptual and methodological individualism is highlighted, though ecological studies alone do not suffice for studying population health. PMID:26535754

  10. What can we expect from epidemiologic studies of chemical mixtures?

    PubMed

    Samet, J M

    1995-12-28

    Determining the health risks of complex mixtures is equally daunting to toxicologists using experimental approaches and to epidemiologists using observational approaches. Accurate exposure estimation is essential in investigating the health consequences of exposures to chemical mixtures; random and non-random errors in exposure estimation typically blunt the sensitivity of epidemiologic studies and constrain interpretation of findings. On the other hand, epidemiologic data have the implicit strength of directly addressing risks of exposures in human populations and, for this reason, the findings of epidemiologic research have received prominence in the development of regulations. Epidemiologic studies have proved informative about many complex mixtures including cigarette smoke, diesel exhaust, and even the human diet, perhaps one of the most complex mixtures to which we are exposed. The continued interest in studying complex chemical mixtures is emphasized by this and other recent meetings directed at the topic. The variety of approaches used by epidemiologists in approaching complex mixtures reflects the difficulty of exposure estimation. Five general strategies can be identified, each with differing underlying assumptions and yielding results with distinct implications from biological and public health perspectives. These include treating the mixture as though it were a single agent, using a single component as a surrogate for the mixture, creating a summary index involving multiple components, attempting to estimate independent effects of individual components, and characterizing the independent and joint effects of key components of the mixture. These approaches have proved successful in establishing the adverse effects of a number of complex chemical mixtures including mainstream and environmental tobacco smoke and outdoor air pollution. New approaches for exposure assessment, including personal monitoring and biomarkers, should strengthen future

  11. Molecular epidemiology and genetic diversity of Blastocystis infection in humans in Italy.

    PubMed

    Mattiucci, S; Crisafi, B; Gabrielli, S; Paoletti, M; Cancrini, G

    2016-02-01

    In order to describe the molecular epidemiology of Blastocystis infection in Italy, 189 isolates, which had been collected during the years 2012-2014 from mildly symptomatic patients, or those affected by inflammatory bowel disease (IBD), irritable bowel syndrome (IBS) or chronic diarrhoea, or otherwise immunosuppressed, were subtyped by sequence analysis of the SSU rRNA gene (536 bp). Six subtypes (STs) were detected: ST1 (15·3%), ST2 (13·8%), ST3 (46·0%), ST4 (21·7%), ST6 (3·2%) and ST8 (0·5%). They clustered in distinct clades, as inferred from Bayesian inference phylogenetic and median joining network analyses. A high genetic differentiation was found at the inter-subtype level; it ranged from Jukes-Cantor (JC) distance = 0·02 (between ST1 and ST4) to JC = 0·11 (between ST6 and ST2). At the intra-ST level, a high genetic homogeneity was registered in ST4, whereas higher genetic variation was found in isolates corresponding to ST1 and ST2. Accordingly, high values of haplotype and nucleotide diversity were observed in ST1, ST2 and ST3. No association was found between patient gender and ST, whereas ST3 and ST1 were significantly more prevalent in patients aged 15-50 years. A significant occurrence of Blastocystis ST4 in patients suffering from IBS, IBD or chronic diarrhoea was observed; in addition, a slight significant association between ST1 and ST3 and IBS patients was found. Multiple correspondence analysis showed some significant contribution of different variables (subtypes, haplotypes, age) in the observed pattern of ordination of the 189 patients in the symptom categories.

  12. Autism in the Faroe Islands. An Epidemiological Study

    ERIC Educational Resources Information Center

    Ellefsen, Asa; Kampmann, Hanna; Billstedt, Eva; Gillberg, I. Carina; Gillberg, Christopher

    2007-01-01

    The Faroe Islands are considered to be a genetic isolate. This population study of the prevalence of autism sought to identify a representative cohort for future genetic studies. In 2002 all schools were screened for autism spectrum disorders. The target population were all children born in 1985 through 1994 and living in the Faroe Islands on…

  13. Environmental Pollution Effects on Reproductive Health – Clinical-Epidemiological Study in Southern Italy

    PubMed Central

    Marra, M.L.; Zullo, F.; De Felice, B.; Nappi, L.; Guida, M.; Trifuoggi, M.; Nappi, C.; Di Spiezio Sardo, A.; Zizolfi, B.; Capece, G.; Visconti, F.; Troisi, J.; Ciccone, C.; Guida, M.

    2012-01-01

    This study aims to address the clinical, statistical and Epidemiological Relationship Between Birth Defects and Environmental Pollution, in the Campania Region and in Salerno. Objectives: We examined four groups of subjects as follows: a sample of pregnant women living in Salerno, a sample of pregnant women living in highly polluted areas, a sample of controls, pregnant women and residents out of the Campania Region, considered in unpolluted areas (Foggia) and in the Salerno area. Methodologies: a toxicological and genetic analysis was conducted on patients examined. Conclusions: there is an epidemiological link between environmental pollution and reproductive health in the Salerno area. Experimentally there are the first evidences of endocrine disruptors by the PCB. It has been inferred an overexpression of the mir-191 as a marker of pollution by dioxin-like compounds. Socially, correct information of populations at risk is necessary and a possible preventive and ongoing medical care must be ensured. PMID:23905062

  14. Overview of Epidemiology, Genetics, Birth Defects, and Chromosome Abnormalities Associated With CDH

    PubMed Central

    Pober, Barbara R.

    2010-01-01

    Congenital diaphragmatic hernia (CDH) is a common and well-studied birth defect. The etiology of most cases remains unknown but increasing evidence points to genetic causation. The data supporting genetic etiologies which are detailed below include the association of CDH with recurring chromosome abnormalities, the existence of CDH-multiplex families, and the co-occurrence of CDH with additional congenital malformations. PMID:17436298

  15. [Epidemiology of dementia: the Hisayama study].

    PubMed

    Kiyohara, Yutaka

    2014-04-01

    A prospective cohort study has been conducted in the elderly of the town of Hisayama in Japan since 1985 to elucidate the trends in the prevalence of dementia and examine risk and protective factors for dementia in the general Japanese population. We revealed that the prevalence of all-cause dementia and Alzheimer's disease significantly increased from 1985 to 2005. In our prospective study, diabetes was associated with significantly increased risk of Alzheimer's disease and vascular dementia, while midlife and late-life hypertensions were significant risk factors for vascular dementia but not for Alzheimer's disease. Meanwhile, physical activity and a dietary pattern which was roughly correspondent to a customary Japanese diet were associated with lower risk of dementia in our population.

  16. Epidemiological studies of sodium transport and hypertension.

    PubMed

    McDonald, A; Trevisan, M; Cooper, R; Stamler, R; Gosch, F; Ostrow, D; Stamler, J

    1987-11-01

    Red blood cell membrane cation transport was measured in five population-based surveys and two randomized, controlled, dietary intervention studies to examine its associations with demographic, biological, and dietary variables in free-living individuals. A total of 508 individuals, 255 with high blood pressure, were studied. Both sexes, blacks and whites, and several age groups were represented. The intervention studies included short-term dietary sodium restriction in normotensive adolescents, and a 4-year multifactorial trial on weight, sodium, and alcohol in hypertensive adults. The findings from these surveys and intervention studies are summarized in this report. Sodium-stimulated lithium countertransport was significantly related to diastolic blood pressure in white adults (r = 0.28, p less than 0.001), and to systolic blood pressure in black children (r = 0.50, p less than 0.005) and white adolescents (r = 0.31, p less than 0.05). Lithium countertransport was related to sex and race, but not age. Body mass index had an independent relationship with lithium countertransport in some age groups. Lithium countertransport was lower in normotensive adults than in both younger and older hypertensive adults. Lithium countertransport did not differ significantly between subjects with hypertension treated with antihypertensive medications and those with untreated hypertension. Short-term dietary sodium restriction did not influence lithium countertransport in normotensive adolescents. Long-term dietary intervention was associated with low lithium countertransport in hypertensive adults able to maintain blood pressure control without medication. These findings indicate that lithium countertransport is related to blood pressure and hypertension among free-living individuals.

  17. Smile line and occlusion: An epidemiological study

    PubMed Central

    Harati, Mahsa; Mostofi, Shahbaz Naser; Jalalian, Ezzatollah; Rezvani, Gholamreza

    2013-01-01

    Background: The purpose of the present study was to discuss some new concepts of the desirable characteristics of smile tooth display. Due to the increasing application of cosmetic dental treatments, there is an increasing need for better understanding of the esthetic principles. Materials and Methods: In the present descriptive study, with 212 participants, included were patients with no history of orthodontic treatment, loss or prosthetic replacement of anterior teeth, extracted teeth, lips with asymmetry or a history of trauma. Chi-square test was used to determine possible significances in the relation of smile line to Angle occlusion class, overbite and overjet and arch form. A P level of <0.05 was set as to be significant. Results: Chi-square test indicated that there was a significant difference between the smile design and overbite, overjet and gender but no statistically significant association was found between the smile design and crossbite, molar Angle classification and arch form. Conclusion: Within the limitations of such studies, it might be concluded that there is a significant and important relation between some occlusal parameters and smile design, which must be considered. PMID:24379858

  18. Epidemiological support for genetic variability at hypothalamic–pituitary–adrenal axis and serotonergic system as risk factors for major depression

    PubMed Central

    Ching-López, Ana; Cervilla, Jorge; Rivera, Margarita; Molina, Esther; McKenney, Kathryn; Ruiz-Perez, Isabel; Rodríguez-Barranco, Miguel; Gutiérrez, Blanca

    2015-01-01

    Background Major depressive disorder (MDD) is a serious, and common psychiatric disorder worldwide. By the year 2020, MDD will be the second cause of disability in the world. The GranadΣp study is the first, to the best of our knowledge, epidemiological study of mental disorders carried out in Andalusia (South Spain), being one of its main objectives to identify genetic and environmental risk factors for MDD and other major psychiatric disorders. In this study, we focused on the possible association of 91 candidate single nucleotide polymorphisms (SNPs) with MDD. Methods A total of 711 community-based individuals participated in the GranadΣp study. All individuals were extensively assessed for clinical, psychological, sociodemographic, life style, and other environmental variables. A biological sample was also collected for subsequent genetic analyses in 91 candidate SNPs for MDD. DSM-IV diagnosis of MDD was used as the outcome variable. Logistic regression analysis assuming an additive genetic model was performed to test the association between MDD and the genetic data. The experiment-wide significance threshold adjusted with the SNP spectral decomposition method provided a maximum P-value (8×10−3) required to identify an association. Haplotype analyses were also performed. Results One SNP (rs623580) located in the tryptophan hydroxylase 1 gene (TPH1; chromosome 11), one intergenic variant (rs9526236) upstream of the 5-hydroxytryptamine receptor 2A gene (HTR2A; chromosome 13), and five polymorphisms (rs17689966, rs173365, rs7209436, rs110402, and rs242924) located in the corticotropin-releasing hormone receptor 1 gene (CRHR1; chromosome 17), all showed suggestive trends for association with MDD (P<0.05). Within CRHR1 gene, the TATGA haplotype combination was found to increase significantly the risk for MDD with an odds ratio =1.68 (95% CI: 1.16–2.42, P=0.006). Conclusion Although limited, perhaps due to insufficient sample size power, our results seem to

  19. Combined Genotypic, Phylogenetic, and Epidemiologic Analyses of Mycobacterium tuberculosis Genetic Diversity in the Rhône Alpes Region, France

    PubMed Central

    Pichat, Catherine; Couvin, David; Carret, Gérard; Frédénucci, Isabelle; Jacomo, Véronique; Carricajo, Anne; Boisset, Sandrine; Dumitrescu, Oana; Flandrois, Jean-Pierre; Lina, Gérard; Rastogi, Nalin

    2016-01-01

    -born vs. 551 (59.4%) Foreign-born. French patients were significantly older (mean age: 58.42 yrs 95%CI [56.04; 60.80]) than Foreign-born patients (mean age: 42.38 yrs. 95%CI [40.75; 44.0]). Conclusion The study underlined the importance of imported TB cases on the genetic diversity and epidemiologic characteristics of circulating MTBC strains in Rhône-Alpes region, France over a large time-period. It helps better understand intricate relationships between certain lineages and geographic origin of the patients, and pinpoints genotypic and phylogenetic specificities of prevailing MTBC strains. Lastly, it also demonstrated a slow decline in isolation of M. africanum lineage in this region between 2000 and 2010. PMID:27128522

  20. Epidemiologic studies of cancer in populations near nuclear facilities.

    PubMed

    Shleien, B; Ruttenber, A J; Sage, M

    1991-12-01

    We reviewed over 40 epidemiologic studies around nuclear power stations, fuel reprocessing plants, and weapons production facilities and testing sites in the United Kingdom, the United States, France, and Canada. We examined these studies for their potential to support a cause and effect relationship between cancer risk and radiation exposure. The extent to which an epidemiologic study supports a causal relation between radiation exposure and increased cancer risk can be evaluated using a set of criteria that have become known as Hill's postulates. In our review, epidemiologic studies yielded results that were biologically plausible and were supported by experimental data, but in almost all of the studies the methodologies were not adequate for evaluating causality. In the majority of cases, the methodologies did not permit examination of dose-response associations, making it impossible to support or refute causal relations. We suggest that investigators consider these issues when designing studies and employ dose reconstruction methodology to estimate radiation doses for specific individuals and population groups.

  1. EPIDEMIOLOGICAL STUDY OF CHILDREN DIAPHYSEAL FEMORAL FRACTURES

    PubMed Central

    Hoffmann, Cassiano Ricardo; Traldi, Eduardo Franceschini; Posser, Alexandre

    2015-01-01

    Objective: To evaluate the personal, fracture, treatment and complication characteristics among patients with pediatric femoral shaft fractures attended at the pediatric orthopedic service of the Joana de Gusmão Children's Hospital. Methods: This was a retrospective cross-sectional study on a population consisting of patients with femoral shaft fractures, aged between birth and 14 years and 11 months, who were divided into four age groups. Information was obtained from medical records and was transferred to a survey questionnaire to present personal, fracture, treatment and complication variables. Results: The study population consisted of 96 patients. Their mean age was 6.8 years. The cases were predominantly among males, comprising closed fractures on the right side, in the middle third with a single line. Regarding fracture etiology, traffic accidents predominated overall in the sample. Most of the patients (74 to 77.1%) presented femoral fractures as their only injury. Conservative treatment predominated in the group younger than six years of age, and surgical treatment in the group aged 6 to 14 years and 11 months. The complications observed until bone union were: discrepancy, infection and movement limitation. The mean time taken for consolidation was 9.6 ± 2.4 weeks, varying with age. Conclusion: The features of these fractures were similar to those described in the literature and the treatment used showed good results. The Joana de Gusmão Children's Hospital has used the treatment proposed in the literature for pediatric femoral shaft fractures. PMID:27042619

  2. Epidemiological studies of natural family planning.

    PubMed

    Gray, R H; Kambic, R T

    1988-07-01

    The prevalence of the use of natural family planning (NFP) can be estimated from sample surveys of married women in the reproductive ages (MWRA). Surveys in developed and developing countries during the past decade indicate that the prevalence of NFP use varies from 0 to 11%. In addition, if one considers NFP use in relation to other contraceptive methods, the percentage of all current contraceptors who use NFP varies from 1 to 35%. This suggests that NFP is an important method in certain countries. Pregnancy rates for NFP vary widely, but most reliable studies report 1-year life-table pregnancy rates between 10 and 25/100 woman-years. The Billings ovulation method consistently has higher pregnancy rates than the sympto-thermal method and NFP users generally have among the highest pregnancy rates compared to other methods. The major safety issue concerning NFP is the risk of adverse pregnancy outcomes associated with aged gametes. There are suggestions from a number of investigations that conceptions distant from ovulation have a higher risk of spontaneous abortion and a higher proportion of male births. The findings with respect to birth defects or multiple pregnancies are less consistent, although some studies have reported an increased risk of chromosomal anomalies.

  3. Epidemiologic studies of Cyclospora cayetanensis in Guatemala.

    PubMed Central

    Bern, C.; Hernandez, B.; Lopez, M. B.; Arrowood, M. J.; de Mejia, M. A.; de Merida, A. M.; Hightower, A. W.; Venczel, L.; Herwaldt, B. L.; Klein, R. E.

    1999-01-01

    In 1996 and 1997, cyclosporiasis outbreaks in North America were linked to eating Guatemalan raspberries. We conducted a study in health-care facilities and among raspberry farm workers, as well as a case-control study, to assess risk factors for the disease in Guatemala. From April 6, 1997, to March 19, 1998, 126 (2.3%) of 5, 552 surveillance specimens tested positive for Cyclospora; prevalence peaked in June (6.7%). Infection was most common among children 1.5 to 9 years old and among persons with gastroenteritis. Among 182 raspberry farm workers and family members monitored from April 6 to May 29, six had Cyclospora infection. In the case-control analysis, 62 (91%) of 68 persons with Cyclospora infection reported drinking untreated water in the 2 weeks before illness, compared with 88 (73%) of 120 controls (odds ratio [OR] 3.8, 95% confidence interval [CI] 1.4, 10.8 by univariate analysis). Other risk factors included water source, type of sewage drainage, ownership of chickens or other fowl, and contact with soil (among children younger than 2 years). PMID:10603209

  4. Vitamin D and cancer: an overview on epidemiological studies.

    PubMed

    Ordóñez Mena, José Manuel; Brenner, Hermann

    2014-01-01

    In recent years, a rapidly increasing number of studies have investigated the relationship of vitamin D with total cancer and site-specific cancer obtaining diverse findings. In this chapter we provide an overview of epidemiological studies of vitamin D intake, 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D serum levels and vitamin D associated polymorphisms in relation to total and site-specific cancer risk. Overall, epidemiological evidence for total cancer is inconclusive. However, a large number of studies support a relationship of vitamin D with colorectal cancer and to a lesser extent with breast cancer. Findings are inconsistent for other cancers including all other gastrointestinal cancers and prostate cancer. Different vitamin D associated polymorphisms were found to be significantly associated to colorectal, breast and prostate cancer risk.

  5. [Epidemiological interventional study on controlling endemic arsenism].

    PubMed

    Li, Y

    1991-03-01

    Residents exposed to high arsenical water in Kuitum area of Xinjiang Autonomous Region were studied by on the spot interventional trial experiment. After ridding arsenic from drinking water, 82.43% of chronic arsenism were either cured or showed improvements of health conditions and no new' cases of arsenism developed during the experiment. The values of arsenic in patiens hair and urine decreased by drinking water free of arsenic, but remained higher than those of normal residents. Our results showed that drinking normal water could help to progressively eliminate arsenic storage from the chronic arsenism. By means of electromyograph (EMG), we found that the nerve conduction velocities of patients increased significantly (P less than 0.01) and that -SH reactivities of peripheral blood corpuscles of patients recovered to the normal level.

  6. [Epidemiologic study of injuries in infants].

    PubMed

    Tursz, A; Lelong, N; Crost, M

    1988-11-01

    Eight hundred fifty-four injuries to children under 2 years of age were analysed. Injuries were more frequent in the second year than in younger infants. No major male predominance was observed. Most injuries were related to home accidents and mainly to mechanical trauma. Burns and poisonings were less frequent but their percentage was higher during the second year. Most lesions were benign, except in case of fall from a height (window falls, falls from baby furniture). Medical cost was rather high due to a 17% rate of hospital admissions and a 4 days average length of stay. Two fatal cases were registered. Sequelae appeared to be rare. Child abuse was seldom suspected and reason for that remains unclear. The study of accidents mechanism leads to think that teaching young children the control of hazardous situations should play a large part in prevention.

  7. MIH: epidemiologic clinic study in paediatric patient

    PubMed Central

    CONDÒ, R.; PERUGIA, C.; MATURO, P.; DOCIMO, R.

    2012-01-01

    SUMMARY The Molar Incisor Hypomineralization (MIH) is a qualitative and quantitative defect of the enamel structure of the first permanent molars, which may vary from 1 to 4 with involvement of maxillary and jaw permanent incisors. Aim. Aim of this study is that to evaluate, among 1500 paediatric patients chosen at random aged between 0 and 14 years, afferent by the Paediatric Dentistry of the Azienda Ospedialiera Policlinico Tor Vergata of Rome from 1996 to 2011, the incidents and the prevalence of the MIH distribution, and furthermore to ascertain the possible relationship with the data described in the literature. Results and discussion. From the sample of 1500 paediatric patients, the number of those affections from MIH has turned out to be pairs to 110 (7.3%) aged between 4 and 15 years, and an average age equal to 9.7. The incidence of the hypoplastic defects is greater in the elements of the permanents series in which the functional class mainly interested is that of the first molars, with a percentage of 39.8%. Regarding the elements of the deciduous series affections from hypoplasia, they turn out to be in all in number of 20 represented in 80% of the cases from the seconds molars while in the remaining 20% of the cases the items involved are the central incisors. About the percentage of elements involved in the MIH: the molars, involved with a frequency of 56%, turn out to be more hit regarding incisors (44%). As reported in the literature, it can be asserted that the MIH can hit in equal measure both the male sex that feminine one. Conclusions. MIH represents a condition quite frequent in the paediatric population. In managing this anomaly takes an essential role in the early diagnosis and in the differential one. The study done underlined the importance of a correct application of the therapeutic protocol which, starting from a careful diagnosis and articulating themselves in the execution of preventive treatments and in severe cases restorative and

  8. Dynamics of the Ovarian Reserve and Impact of Genetic and Epidemiological Factors on Age of Menopause1

    PubMed Central

    Pelosi, Emanuele; Simonsick, Eleanor; Forabosco, Antonino; Garcia-Ortiz, Jose Elias; Schlessinger, David

    2015-01-01

    The narrow standard age range of menopause, ∼50 yr, belies the complex balance of forces that govern the underlying formation and progressive loss of ovarian follicles (the “ovarian reserve” whose size determines the age of menopause). We show here the first quantitative graph of follicle numbers, distinguished from oocyte counts, across the reproductive lifespan, and review the current state of information about genetic and epidemiological risk factors in relation to possible preservation of reproductive capacity. In addition to structural X-chromosome changes, several genes involved in the process of follicle formation and/or maintenance are implicated in Mendelian inherited primary ovarian insufficiency (POI), with menopause before age 40. Furthermore, variants in a largely distinct cohort of reported genes—notably involved in pathways relevant to atresia, including DNA repair and cell death—have shown smaller but additive effects on the variation in timing of menopause in the normal range, early menopause (age <45), and POI. Epidemiological factors show effect sizes comparable to those of genetic factors, with smoking accounting for about 5% of the risk of early menopause, equivalent to the summed effect of the top 17 genetic variants. The identified genetic and epidemiological factors underline the importance of early detection of reproductive problems to enhance possible interventions. PMID:25904009

  9. Epidemiological Study of Paratuberculosis in Wild Rabbits in Scotland

    PubMed Central

    Greig, Alastair; Stevenson, Karen; Henderson, Dennis; Perez, Valentin; Hughes, Valerie; Pavlik, Ivo; Hines, Murray E.; McKendrick, Iain; Sharp, J. Michael

    1999-01-01

    A survey of 22 farms confirmed the presence of paratuberculosis in wild rabbits in Scotland. Regional differences were apparent in the prevalence of the disease in rabbits, with a significantly higher incidence occurring in the Tayside region. Statistical analysis showed a significant relationship between a previous history or current problem of paratuberculosis in cattle and the presence of paratuberculosis in rabbits on the farms. Molecular genetic typing techniques could not discriminate between selected rabbit and cattle isolates from the same or different farms, suggesting that the same strain may infect and cause disease in both species and that interspecies transmission may occur. The possibility of interspecies transmission and the involvement of wildlife in the epidemiology of paratuberculosis have important implications for the control of the disease. PMID:10325318

  10. Carcinoma of the cervix: an epidemiologic study.

    PubMed

    Terris, M; Oalmann, M C

    1960-12-01

    122 patients with histologically confirmed squamous cell carcinoma of the cervix admitted to the gynecological wards of Charity Hospital in New Orleans from July 1, 1959, through March 31, 1960, were studied; suitable controls were selected from the same wards. All interviews were conducted by the same interviewer nurse who was unaware of the diagnoses. Hospital charts were later examined. Educational level of patients, occupation of husband and father, residence, original diagnosis, and religion were similar to those of controls. Less than 1/3 had more than grammar school education. Most husbands and fathers were farmers of unskilled laborers. In only 1/5 of the patients had the original cancer diagnosis been made by private physicians or at noncharity hospitals. About 45% were Catholics, 45% Baptists, and the remaining 10% other Protestant denominations. 49% of the patients and 43% of the controls reported 6 or more pregnancies. Douching practices were similar to controls; few had ever used other contraceptive measures. 13 patients and 6 controls had positive serological tests for syphilis. Only 6, 1 patient and 5 controls, had never been married. Of cancer patients, 47% had been married more than once vs. 16% of controls. 34% of the patients with cancer were married before the age of 17 vs. 14% of controls. 54% of patients with cancer and 26% of controls reported extramarital partners. 53% of patients had 1st coitus before age 17 vs. 26% of the controls. There was a considerably higher frequency of coitus in patients than in controls. It is concluded that no relation between number of pregnancies and cancer was shown. Douching with coal tar derivatives was not a factor. The association of carcinoma and syphilis was not certain as many had never had a serological test. The effect of circumcision of partners was not determined as it was often unknown. A significant association was shown with early marriage, extramarital relations, coitus at an early age, and

  11. Childhood accidents. Three epidemiological studies on the etiology.

    PubMed

    Gustafsson, L H

    1977-01-01

    Three studies on childhood accidents are presented. The aim was to study the importance of different factors regarding the accidents in question. The following factors have then been taken into consideration: the enviromental hazard, the accident proneness, the supervision and the education. Methodologically the investigations were carried out with an epidemiological technique. One is of a descriptive nature and the other two more analytically oriented. The studies are based on two different 1-year-materials consisting of accidents among children recorded in the emergency departments of Ostersund Hospital and the University Hospital in Uppsala. The results indicate that risk factors in the children's physical milieu played an important role in the occurrence of the accidents: clearly identifiable risk factors in the environment could be connected with 52% of the accidents, whereas some deficiency in supervision was noted in 20%. The investigators could identify a number of specific risk factors. Attempts were made to examine how frequency and type of childhood accidents vary with the population structure and social structure in well-defined housing areas, but the results were hard to evaluate because of methodological problems. The results are presented against the background of a detailed discussion on central methodological problems in epidemiological accident research. It is pointed out in particular that epidemiological methods have clear limitations in attempts at studying the low-frequency events that each individual type of accident in fact comprises. It is of great importance that in future research, side by side with the traditional epidemiological methods, other techniques are tested with the aim of obtaining maximal usable information from a detailed study of individual accidents and their backgrounds. PMID:857307

  12. Genetic studies in alcohol research

    SciTech Connect

    Karp, R.W.

    1994-12-15

    The National Institute on Alcohol Abuse and Alcoholism (NIAAA) supports research to elucidate the specific genetic factors, now largely unknown, which underlie susceptibility to alcoholism and its medical complications (including fetal alcohol syndrome). Because of the genetic complexity and heterogeneity of alcoholism, identification of the multiple underlying factors will require the development of new study designs and methods of analysis of data from human families. While techniques of genetic analysis of animal behavioral traits (e.g., targeted gene disruption, quantitative trait locus (QTL) mapping) are more powerful that those applicable to humans (e.g., linkage and allelic association studies), the validation of animal behaviors as models of aspects of human alcoholism has been problematic. Newly developed methods for mapping QTL influencing animal behavioral traits can not only permit analyses of human family data to be directly informed by the results of animal studies, but can also serve as a novel means of validating animal models of aspects of alcoholism. 55 refs.

  13. Late-onset primary dystonia in Zhejiang province of China: a service-based epidemiological study.

    PubMed

    Wang, Li; Chen, Yin; Hu, Beibei; Hu, Xingyue

    2016-01-01

    Dystonia is characterized by sustained muscle contractions, causing repetitive movements and abnormal postures. The epidemiological study of dystonia of Chinese population was limited reported. In this study, we investigated the epidemiology of primary dystonia, and its clinical characteristics in an adult population in China. We identified all dystonia patients from the movement disorders database and botulinum toxin clinic between 2009 and 2013. The medical records were reviewed to verify the diagnosis of dystonia, and demographic and clinical data were collected. A total of 1481 patients with primary dystonia were studied. The most common focal dystonia were blepharospasm (56.4 %), cervical dystonia (36.7 %), limb dystonia (3.4 %), oromandibular dystonia (2.9 %) and laryngeal dystonia (0.6 %). Males with primary dystonia were found to have an earlier age of onset. A female predominance was noted for most of the primary dystonia, with a men to women ratio (M:F) of 1:2.01. The minimum estimate of prevalence of primary dystonia was 27.0 (95 % confidence interval: 25.6-28.3) per million persons in this study. Despite the difference in genetic background and geographic area, the epidemiological features of dystonia in China from our study share most features around the world, such as women dystonia dominance, early-onset age of dystonia with women, etc. But East Asia countries (China and Japan) may share more common features of dystonia.

  14. Assessing the first wave of epidemiological studies of nanomaterial workers

    PubMed Central

    Tsai, Candace S. J.; Pelclova, Daniela; Schubauer-Berigan, Mary K.; Schulte, Paul A.

    2015-01-01

    The results of early animal studies of engineered nanomaterials (ENMs) and air pollution epidemiology suggest that it is important to assess the health of ENM workers. Initial epidemiological studies of workers’ exposure to ENMs (<100 nm) are reviewed and characterized for their study designs, findings, and limitations. Of the 15 studies, 11 were cross-sectional, 4 were longitudinal (1 was both cross-sectional and longitudinal in design), and 1 was a descriptive pilot study. Generally, the studies used biologic markers as the dependent variables. All 11 cross-sectional studies showed a positive relationship between various biomarkers and ENM exposures. Three of the four longitudinal studies showed a negative relationship; the fourth showed positive findings after a 1-year follow-up. Each study considered exposure to ENMs as the independent variable. Exposure was assessed by mass concentration in 10 studies and by particle count in six studies. Six of them assessed both mass and particle concentrations. Some of the studies had limited exposure data because of inadequate exposure assessment. Generally, exposure levels were not very high in comparison to those in human inhalation chamber studies, but there were some exceptions. Most studies involved a small sample size, from 2 to 258 exposed workers. These studies represent the first wave of epidemiological studies of ENM workers. They are limited by small numbers of participants, inconsistent (and in some cases inadequate) exposure assessments, generally low exposures, and short intervals between exposure and effect. Still, these studies are a foundation for future work; they provide insight into where ENM workers are experiencing potentially adverse effects that might be related to ENM exposures. PMID:26635494

  15. [Descriptive epidemiologic study of 514 cases of bladder cancer].

    PubMed

    Calatayud Sarthou, A; Cortes Vizcaino, C; Talamante Serrula, S; Corella Piquer, D

    1994-01-01

    A descriptive epidemiological study was conducted on the characteristics and risk factors of 514 cases of bladder cancer. The results show a higher prevalence in males aged 70 or older. A higher incidence was found in those with a lower occupational level. There is a relationship with smoking and a Quetelet obesity score higher than normal. Anatomo-pathologically, the transitional cell type was the most common. A history of hematuria and obstructive disorders, basically arising from the prostate, were frequently found.

  16. Biologically based epidemiological studies of electric power and cancer

    SciTech Connect

    Stevens, R.G.

    1993-12-01

    Use of electricity is a hallmark of the industrialization process, but there has been no suspicion that electricity could increase the risk of cancer. Recently, however, a number of epidemiologic studies have suggested that electromagnetic fields (EMF) may do just that. Although few cancer experiments have been done yet, there are a number of biological effects of EMF reported in the literature that might provide bases for designing cancer experiments and epidemiologic studies. These include effects of EMF on: (a) DNA transcription and translation, (b) calcium balance in cells, and (c) pineal production of melatonin. Alterations in DNA transcription and translation could have pleiotropic effects. Disruption of calcium homeostasis has many implications including oncogene activation, promotional activity via protein kinases and ornithine decarboxylase (ODC), and increasing oxidative stress. Reduction of melatonin suggests a possible increased risk of cancers of hormone-dependent tissues such as breast and prostate. The idea that a cancer-causing agent must either be an initiator or a promoter should be discarded; indeed, the phenomenologic meaning of these two terms has become confused with imputed mechanistic necessity in recent years. Agents that affect division of normal cells or of fully transformed cells can play an important role in clinical cancer development quite apart from initiation or promotion. Epidemiologic studies of EMF and cancer should attempt to take account of other products of electric power (e.g., light at night) or factors associated with occupational EMF exposure (e.g., toxic chemicals) that may increase cancer risk and therefore act as cofactors or confounders. Epidemiology and laboratory studies should act synergistically in determining if there is a problem and identifying mitigation strategies if needed. 84 refs., 3 figs., 1 tab.

  17. Epidemiology of a thermonuclear bomb-burst over Nashville, Tennessee: a theoretic study.

    PubMed

    Quinn, R W

    1983-07-01

    A thermonuclear bomb explosion over any city in the world would have a devastating effect on the population and environment. For those who survive, with or without injuries, life would become primitive with little or no uncontaminated food or water, and with inadequate housing, fuel, and medical care, resulting in a breakdown of family and interpersonal relationships. This theoretic study of the potential outcome of a thermonuclear bomb-burst over Nashville, Tennessee, discusses epidemiologically the wide range of medical and psychologic effects from the direct trauma of blast and fire, widespread epidemics of otherwise controlled disease, long-term chronic illness, genetic damage, and catastrophic environmental havoc.

  18. Colorectal Cancer Epidemiology in the Nurses’ Health Study

    PubMed Central

    Lee, Dong Hoon; Giovannucci, Edward L.

    2016-01-01

    Objectives. To review the contribution of the Nurses’ Health Study (NHS) to identifying risk and protective factors for colorectal adenomas and colorectal cancer (CRC). Methods. We performed a narrative review of the publications using the NHS between 1976 and 2016. Results. Existing epidemiological studies using the NHS have reported that red and processed meat, alcohol, smoking, and obesity were associated with an increased risk of CRC, whereas folate, calcium, vitamin D, aspirin, and physical activity were associated with decreased risk of CRC. Moreover, modifiable factors, such as physical activity, vitamin D, folate, insulin and insulin-like growth factor binding protein-1, and diet quality, were identified to be associated with survival among CRC patients. In recent years, molecular pathological epidemiological studies have been actively conducted and have shown refined results by molecular subtypes of CRC. Conclusions. The NHS has provided new insights into colorectal adenomas, CRC etiology, and pathogenic mechanisms. With its unique strengths, the NHS should continue to contribute to the field of CRC epidemiology and play a major role in public health. PMID:27459444

  19. Fetal haemoglobin in sickle-cell disease: from genetic epidemiology to new therapeutic strategies.

    PubMed

    Lettre, Guillaume; Bauer, Daniel E

    2016-06-18

    Sickle-cell disease affects millions of individuals worldwide, but the global incidence is concentrated in Africa. The burden of sickle-cell disease is expected to continue to rise over the coming decades, adding to stress on the health infrastructures of many countries. Although the molecular cause of sickle-cell disease has been known for more than half a century, treatment options remain greatly limited. Allogeneic haemopoietic stem-cell transplantation is the only existing cure but is limited to specialised clinical centres and remains inaccessible for most patients. Induction of fetal haemoglobin production is a promising strategy for the treatment of sickle-cell disease. In this Series paper, we review scientific breakthroughs in epidemiology, genetics, and molecular biology that have brought reactivation of fetal haemoglobin to the forefront of sickle-cell disease research. Improved knowledge of the regulation of fetal haemoglobin production in human beings and the development of genome editing technology now support the design of innovative therapies for sickle-cell disease that are based on fetal haemoglobin.

  20. Hepatitis C virus genotype 6: Virology, epidemiology, genetic variation and clinical implication

    PubMed Central

    Thong, Vo Duy; Akkarathamrongsin, Srunthron; Poovorawan, Kittiyod; Tangkijvanich, Pisit; Poovorawan, Yong

    2014-01-01

    Hepatitis C virus (HCV) is a serious public health problem affecting 170 million carriers worldwide. It is a leading cause of chronic hepatitis, cirrhosis, and liver cancer and is the primary cause for liver transplantation worldwide. HCV genotype 6 (HCV-6) is restricted to South China, South-East Asia, and it is also occasionally found in migrant patients from endemic countries. HCV-6 has considerable genetic diversity with 23 subtypes (a to w). Although direct sequencing followed by phylogenetic analysis is the gold standard for HCV-6 genotyping and subtyping, there are also now rapid genotyping tests available such as the reverse hybridization line probe assay (INNO-LiPA II; Innogenetics, Zwijnaarde, Belgium). HCV-6 patients present with similar clinical manifestations as patients infected with other genotypes. Based on current evidence, the optimal treatment duration of HCV-6 with pegylated interferon/ribavirin should be 48 wk, although a shortened treatment duration of 24 wk could be sufficient in patients with low pretreatment viral load who achieve rapid virological response. In addition, the development of direct-acting antiviral agents is ongoing, and they give high response rate when combined with standard therapy. Herein, we review the epidemiology, classification, diagnosis and treatment as it pertain to HCV-6. PMID:24659883

  1. Fetal haemoglobin in sickle-cell disease: from genetic epidemiology to new therapeutic strategies.

    PubMed

    Lettre, Guillaume; Bauer, Daniel E

    2016-06-18

    Sickle-cell disease affects millions of individuals worldwide, but the global incidence is concentrated in Africa. The burden of sickle-cell disease is expected to continue to rise over the coming decades, adding to stress on the health infrastructures of many countries. Although the molecular cause of sickle-cell disease has been known for more than half a century, treatment options remain greatly limited. Allogeneic haemopoietic stem-cell transplantation is the only existing cure but is limited to specialised clinical centres and remains inaccessible for most patients. Induction of fetal haemoglobin production is a promising strategy for the treatment of sickle-cell disease. In this Series paper, we review scientific breakthroughs in epidemiology, genetics, and molecular biology that have brought reactivation of fetal haemoglobin to the forefront of sickle-cell disease research. Improved knowledge of the regulation of fetal haemoglobin production in human beings and the development of genome editing technology now support the design of innovative therapies for sickle-cell disease that are based on fetal haemoglobin. PMID:27353686

  2. Improving estimates of exposures for epidemiologic studies of plutonium workers.

    PubMed

    Ruttenber, A J; Schonbeck, M; McCrea, J; McClure, D; Martyny, J

    2001-01-01

    Epidemiologic studies of nuclear facilities usually focus on relations between cancer and doses from external penetrating radiation, and describe these exposures with little detail on measurement error and missing data. We demonstrate ways to document complex exposures to nuclear workers with data on external and internal exposures to ionizing radiation and toxic chemicals. We describe methods for assessing internal exposures to plutonium and external doses from neutrons; the use of a job exposure matrix for estimating chemical exposures; and methods for imputing missing data for exposures and doses. For plutonium workers at Rocky Flats, errors in estimating neutron doses resulted in underestimating the total external dose for production workers by about 16%. Estimates of systemic deposition do not correlate well with estimates of organ doses. Only a small percentage of workers had exposures to toxic chemicals, making epidemiologic assessments of risk difficult. PMID:11319050

  3. Consistency of external dosimetry in epidemiologic studies of nuclear workers

    SciTech Connect

    Fix, J.J.; Gilbert, E.S.

    1991-10-01

    To make the best use of available epidemiologic data in assessing risks from exposure to low-level radiation, it is important that biases and uncertainties in estimated doses be understood and documented. With this understanding, analyses of mortality data can be strengthened by including the use of correction factors where judged appropriate, excluding portions of the data where uncertainty in dose estimates is judged to be very large, and conducting sensitivity analyses to examine the effect of alternative assumptions about dosimetry errors and biases on results. It is hoped that the pooling of data from several epidemiologic studies and improved understanding of dosimetry will lead to better estimates of radiation risks. 10 refs., 4 tabs.

  4. Multicollinearity in Regression Analyses Conducted in Epidemiologic Studies

    PubMed Central

    Vatcheva, Kristina P.; Lee, MinJae; McCormick, Joseph B.; Rahbar, Mohammad H.

    2016-01-01

    The adverse impact of ignoring multicollinearity on findings and data interpretation in regression analysis is very well documented in the statistical literature. The failure to identify and report multicollinearity could result in misleading interpretations of the results. A review of epidemiological literature in PubMed from January 2004 to December 2013, illustrated the need for a greater attention to identifying and minimizing the effect of multicollinearity in analysis of data from epidemiologic studies. We used simulated datasets and real life data from the Cameron County Hispanic Cohort to demonstrate the adverse effects of multicollinearity in the regression analysis and encourage researchers to consider the diagnostic for multicollinearity as one of the steps in regression analysis. PMID:27274911

  5. Development and validation of a robust automated analysis of plasma phospholipid fatty acids for metabolic phenotyping of large epidemiological studies.

    PubMed

    Wang, Laura Yun; Summerhill, Keith; Rodriguez-Canas, Carmen; Mather, Ian; Patel, Pinal; Eiden, Michael; Young, Stephen; Forouhi, Nita G; Koulman, Albert

    2013-01-01

    A fully automated, high-throughput method was developed to profile the fatty acids of phospholipids from human plasma samples for application to a large epidemiological sample set (n > 25,000). We report here on the data obtained for the quality-control materials used with the first 860 batches, and the validation process used. The method consists of two robotic systems combined with gas chromatography, performing lipid extraction, phospholipid isolation, hydrolysis and derivatization to fatty-acid methyl esters, and on-line analysis. This is the first report showing that fatty-acid profiling is an achievable strategy for metabolic phenotyping in very large epidemiological and genetic studies. PMID:23618465

  6. Development and validation of a robust automated analysis of plasma phospholipid fatty acids for metabolic phenotyping of large epidemiological studies

    PubMed Central

    2013-01-01

    A fully automated, high-throughput method was developed to profile the fatty acids of phospholipids from human plasma samples for application to a large epidemiological sample set (n > 25,000). We report here on the data obtained for the quality-control materials used with the first 860 batches, and the validation process used. The method consists of two robotic systems combined with gas chromatography, performing lipid extraction, phospholipid isolation, hydrolysis and derivatization to fatty-acid methyl esters, and on-line analysis. This is the first report showing that fatty-acid profiling is an achievable strategy for metabolic phenotyping in very large epidemiological and genetic studies. PMID:23618465

  7. Diagnostic Studies of Temporomandibular Disorders: Challenges From an Epidemiologic Perspective

    PubMed Central

    Dworkin, Samuel F.; LeResche, Linda; Von Korff, Michael R.

    1990-01-01

    Adequate data on the incidence, prevalence, natural history, and clinical course of temperomandibular disorders (TMD) and other chronic pain conditions are largely lacking, though the need to derive such basic data is recognized by clinicians, researchers, and public health agencies. This paper discusses challenges to the epidemiologic study of TMD diagnosis. These challenges include: • Case definition: There is currently poor agreement regarding which combinations of clinical and psychosocial findings differentially define cases of TMD • Differentiation of normal variation v pathophysiologic signs: To what extent do commonly gathered clinical measurements constitute pathophysiologic signs of TMD v reflect normal biologic variation • Reliability of clinical measurement: Factors influencing reliability of clinical signs and reliability of examiners have not been adequately assessed • Progressive v self-limiting disease activity: Do TMD subtypes represent a continuum of pathologic disease activity, or nonmutually exclusive categories describing largely symptomatic pain conditions that are selflimiting or stable. It is recommended that epidemiologic studies not be constrained by a priori definitions of TMD subtypes, but continue to gather data on clinical signs and symptoms that have theoretical and clinical relevance to mandibular dysfunction and psychosocial status. An approach is proposed for development of reliable and valid criteria of TMD subtypes suitable for epidemiologic research. PMID:2085194

  8. TIME-INTEGRATED EXPOSURE MEASURES TO IMPROVE THE PREDICTIVE POWER OF EXPOSURE CLASSIFICATION FOR EPIDEMIOLOGIC STUDIES

    EPA Science Inventory

    Accurate exposure classification tools are required to link exposure with health effects in epidemiological studies. Although long-term integrated exposure measurements are a critical component of exposure assessment, the ability to include these measurements into epidemiologic...

  9. 10 CFR 602.5 - Epidemiology and Other Health Studies Financial Assistance Program.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Epidemiology and Other Health Studies Financial Assistance Program. 602.5 Section 602.5 Energy DEPARTMENT OF ENERGY (CONTINUED) ASSISTANCE REGULATIONS EPIDEMIOLOGY AND OTHER HEALTH STUDIES FINANCIAL ASSISTANCE PROGRAM § 602.5 Epidemiology and Other Health...

  10. Molecular epidemiology studies on occupational and environmental exposure to mutagens and carcinogens, 1997-1999.

    PubMed Central

    Srám, R J; Binková, B

    2000-01-01

    Molecular epidemiology is a new and evolving area of research, combining laboratory measurement of internal dose, biologically effective dose, biologic effects, and influence of individual susceptibility with epidemiologic methodologies. Biomarkers evaluated were selected according to basic scheme: biomarkers of exposure--metabolites in urine, DNA adducts, protein adducts, and Comet assay parameters; biomarkers of effect--chromosomal aberrations, sister chromatid exchanges, micronuclei, mutations in the hypoxanthine-guanine phosphoribosyltransferase gene, and the activation of oncogenes coding for p53 or p21 proteins as measured on protein levels; biomarkers of susceptibility--genetic polymorphisms of genes CYP1A1, GSTM1, GSTT1, NAT2. DNA adducts measured by 32P-postlabeling are the biomarker of choice for the evaluation of exposure to polycyclic aromatic hydrocarbons. Protein adducts are useful as a biomarker for exposure to tobacco smoke (4-aminobiphenyl) or to smaller molecules such as acrylonitrile or 1,3-butadiene. Of the biomarkers of effect, the most common are cytogenetic end points. Epidemiologic studies support the use of chromosomal breakage as a relevant biomarker of cancer risk. The use of the Comet assay and methods analyzing oxidative DNA damage needs reliable validation for human biomonitoring. Until now there have not been sufficient data to interpret the relationship between genotypes, biomarkers of exposure, and biomarkers of effect for assessing the risk of human exposure to mutagens and carcinogens. PMID:10698723

  11. Epidemiology, Comorbidity, and Behavioral Genetics of Antisocial Personality Disorder and Psychopathy

    PubMed Central

    Werner, Kimberly B.; Few, Lauren R.; Bucholz, Kathleen K.

    2015-01-01

    Psychopathy is theorized as a disorder of personality and affective deficits while antisocial personality disorder (ASPD) diagnosis is primarily behaviorally based. While ASPD and psychopathy are similar and are highly comorbid with each other, they are not synonymous. ASPD has been well studied in community samples with estimates of its lifetime prevalence ranging from 1-4% of the general population.4,5 In contrast, psychopathy is almost exclusively investigated within criminal populations so that its prevalence in the general population has been inferred by psychopathic traits rather than disorder (1%). Differences in etiology and comorbidity with each other and other psychiatric disorders of these two disorders are also evident. The current article will briefly review the epidemiology, etiology, and comorbidity of ASPD and psychopathy, focusing predominately on research completed in community and clinical populations. This paper aims to highlight ASPD and psychopathy as related, but distinct disorders. PMID:26594067

  12. Epidemiology and molecular genetics of colorectal cancer in iran: a review.

    PubMed

    Malekzadeh, Reza; Bishehsari, Faraz; Mahdavinia, Mahboobeh; Ansari, Reza

    2009-03-01

    Although the incidence of colorectal cancer in Iranian older age subjects is currently very low compared to Western population, the younger generation is experiencing an accelerated rate approaching the Western rates and the burden of disease will increase dramatically in near future. The high frequency of positive family history of colorectal cancer in Iranian patients indicates that a significant number of colorectal cancers in Iran arise in family members and relatives of colorectal cancer patients. It is clear that the familial clustering of colorectal cancer is more often seen in younger probands and cancer located in the right side of the colon. These epidemiologic findings call for a broader attempt to promote public awareness and screening strategies in those families with a member affected by colorectal cancer, especially at younger age or with proximal tumors. Based on our present understanding, the possibility of preventing or curing most colon and rectal cancers is now plausible. The molecular biology of colon cancer has been the subject of many researches and is better understood than those for any other solid cancer and have established an important example for cancer research. It is now clear that colorectal cancer develops as the result of genetic and epigenetic alterations that lead to malignant transformation of normal mucosa. In spite of these scientific progresses and the fact that screening can reduce the rate of death by detecting early cancer or premalignant polyps, the rate of screening is very low globally and negligible in Iran and many other developing countries which is due to cost, resistance by physicians, patients, and the healthcare system. In Iran screening should at least be started in family members at earlier age with colonoscopy as the preferred modality of screening method. PMID:19249887

  13. A method for meta-analysis of epidemiological studies.

    PubMed

    Einarson, T R; Leeder, J S; Koren, G

    1988-10-01

    This article presents a stepwise approach for conducting a meta-analysis of epidemiological studies based on proposed guidelines. This systematic method is recommended for practitioners evaluating epidemiological studies in the literature to arrive at an overall quantitative estimate of the impact of a treatment. Bendectin is used as an illustrative example. Meta-analysts should establish a priori the purpose of the analysis and a complete protocol. This protocol should be adhered to, and all steps performed should be recorded in detail. To aid in developing such a protocol, we present methods the researcher can use to perform each of 22 steps in six major areas. The illustrative meta-analysis confirmed previous traditional narrative literature reviews that Bendectin is not related to teratogenic outcomes in humans. The overall summary odds ratio was 1.01 (chi 2 = 0.05, p = 0.815) with a 95 percent confidence interval of 0.66-1.55. When the studies were separated according to study type, the summary odds ratio for cohort studies was 0.95 with a 95 percent confidence interval of 0.62-1.45. For case-control studies, the summary odds ratio was 1.27 with a 95 percent confidence interval of 0.83-1.94. The corresponding chi-square values were not statistically significant at the p = 0.05 level.

  14. Cohort Profile: The Framingham Heart Study (FHS): overview of milestones in cardiovascular epidemiology.

    PubMed

    Tsao, Connie W; Vasan, Ramachandran S

    2015-12-01

    The Framingham Heart Study (FHS) has conducted seminal research defining cardiovascular disease (CVD) risk factors and fundamentally shaping public health guidelines for CVD prevention over the past five decades. The success of the Original Cohort, initiated in 1948, paved the way for further epidemiological research in preventive cardiology. Due to the keen observations suggesting the role of shared familial factors in the development of CVD, in 1971 the FHS began enroling the second generation cohort, comprising the children of the Original Cohort and the spouses of the children. In 2002, the third generation cohort, comprising the grandchildren of the Original Cohort, was initiated to additionally explore genetic contributions to CVD in greater depth. Additionally, because of the predominance of White individuals of European descent in the three generations of FHS participants noted above, the Heart Study enrolled the OMNI1 and OMNI2 cohorts in 1994 and 2003, respectively, aimed to reflect the current greater racial and ethnic diversity of the town of Framingham. All FHS cohorts have been examined approximately every 2-4 years since the initiation of the study. At these periodic Heart Study examinations, we obtain a medical history and perform a cardiovascular-focused physical examination, 12-lead electrocardiography, blood and urine samples testing and other cardiovascular imaging studies reflecting subclinical disease burden.The FHS has continually evolved along the cutting edge of cardiovascular science and epidemiological research since its inception. Participant studies now additionally include study of cardiovascular imaging, serum and urine biomarkers, genetics/genomics, proteomics, metabolomics and social networks. Numerous ancillary studies have been established, expanding the phenotypes to encompass multiple organ systems including the lungs, brain, bone and fat depots, among others. Whereas the FHS was originally conceived and designed to study the

  15. Cohort Profile: The Framingham Heart Study (FHS): overview of milestones in cardiovascular epidemiology.

    PubMed

    Tsao, Connie W; Vasan, Ramachandran S

    2015-12-01

    The Framingham Heart Study (FHS) has conducted seminal research defining cardiovascular disease (CVD) risk factors and fundamentally shaping public health guidelines for CVD prevention over the past five decades. The success of the Original Cohort, initiated in 1948, paved the way for further epidemiological research in preventive cardiology. Due to the keen observations suggesting the role of shared familial factors in the development of CVD, in 1971 the FHS began enroling the second generation cohort, comprising the children of the Original Cohort and the spouses of the children. In 2002, the third generation cohort, comprising the grandchildren of the Original Cohort, was initiated to additionally explore genetic contributions to CVD in greater depth. Additionally, because of the predominance of White individuals of European descent in the three generations of FHS participants noted above, the Heart Study enrolled the OMNI1 and OMNI2 cohorts in 1994 and 2003, respectively, aimed to reflect the current greater racial and ethnic diversity of the town of Framingham. All FHS cohorts have been examined approximately every 2-4 years since the initiation of the study. At these periodic Heart Study examinations, we obtain a medical history and perform a cardiovascular-focused physical examination, 12-lead electrocardiography, blood and urine samples testing and other cardiovascular imaging studies reflecting subclinical disease burden.The FHS has continually evolved along the cutting edge of cardiovascular science and epidemiological research since its inception. Participant studies now additionally include study of cardiovascular imaging, serum and urine biomarkers, genetics/genomics, proteomics, metabolomics and social networks. Numerous ancillary studies have been established, expanding the phenotypes to encompass multiple organ systems including the lungs, brain, bone and fat depots, among others. Whereas the FHS was originally conceived and designed to study the

  16. Circular epidemiology.

    PubMed

    Kuller, L H

    1999-11-01

    Circular epidemiology can be defined as the continuation of specific types of epidemiologic studies beyond the point of reasonable doubt of the true existence of an important association or the absence of such an association. Circular epidemiology is an extreme example of studies of the consistency of associations. A basic problem for epidemiology is the lack of a systematic approach to acquiring new knowledge to reach a goal of improving public health and preventive medicine. For epidemiologists, research support unfortunately is biased toward the continued study of already proven hypotheses. Circular epidemiology, however, freezes at one point in the evolution of epidemiologic studies, failing to move from descriptive to analytical case-control and longitudinal studies, for example, to experimental, clinical trials. Good epidemiology journals are filled with very well-conducted epidemiologic studies that primarily repeat the obvious or are variations on the theme.

  17. A need for phenotyping pediatric asthma in epidemiologic studies.

    PubMed

    Zejda, J

    2014-05-01

    Epidemiological studies on pediatric asthma reveal a substantial variation in the prevalence of the disease. Differing population-specific data on the occurrence of the disease, defined as a physician-diagnosed asthma, are attributed to differences in risk factors, nosologic preferences, availability of diagnostic facilities, socio-economic factors, etc. As a result some findings could be affected by so-called underdiagnosis although in some populations overdiagnosis of pediatric asthma cannot be excluded. Diagnosing pediatric asthma can be difficult even in clinical setting. Among factors hampering that process heterogeneity of the disease plays an important role. Evidence show that asthma is not a single disease but it is a complex syndrome composed of similarly manifested disorders. As a result a significant scientific effort is directed to describe phenotypes of pediatric asthma. Two well known approaches to phenotyping include clinical and etiological assessment. The former approach takes into account the clinical presentation. The latter one involves recognition of the circumstances that precede the symptom manifestation in the disease: 'virus-induced asthma', 'exercise-induced asthma', 'allergen-induced asthma', 'unresolved asthma'. The mentioned approaches do not provide means of complete classification of the disease. A relatively novel and promising research area in the field of phenotyping asthma takes advantage of biomonitoring. Biomarkers of allergy and immunological responses are used in clinical setting (for example: assessment of atopy, eosinophils count, FENO), however many tests need more validation. Of particular interest is availability of non-invasive biomarkers, their repeatability, sensitivity and specificity. Several national and international guidelines and recommendations point to the importance of specific studies addressing the role of biomonitoring in phenotyping asthma. Еpidemiological perspective investigations into biomarkers in

  18. Drug abuse in Nigeria: a review of epidemiological studies.

    PubMed

    Pela, O A; Ebie, J C

    1982-01-01

    This paper reviews the available literature on the epidemiology of drug abuse in Nigeria. Depending on the definition used, substances which are abused include antibiotics, antidiarrhoeals, laxatives, pain-relieving drugs, sedatives, amphetamines and cannabis. This review is, however, limited to studies on substances which alter behaviour or mood. These drugs include cannabis, sedative-hypnotics, amphetamines and alcohol. For some classes of drugs there has been a noticeable shift in patterns of drug abuse, for example, from abuse of methaqualone to barbiturates. The abuse of volatile solvents and other substances has also been noted. The review shows that there is no age limit among drug abusers. Studies on the influence of social class have been contradictory. Factors which indicate a predisposition to initial drug use have been similar to those reported in other cultures. Although the studies agreed on the classes of drugs abused and the changing patterns of drug abuse, there has been no uniform reporting system. This situation is attributed to financial constraints. Large-scale surveys which should incorporate most of the core items in any epidemiological study on substance abuse have been suggested. PMID:6985029

  19. Mycobacterium tuberculosis complex genetic diversity: mining the fourth international spoligotyping database (SpolDB4) for classification, population genetics and epidemiology

    PubMed Central

    Brudey, Karine; Driscoll, Jeffrey R; Rigouts, Leen; Prodinger, Wolfgang M; Gori, Andrea; Al-Hajoj, Sahal A; Allix, Caroline; Aristimuño, Liselotte; Arora, Jyoti; Baumanis, Viesturs; Binder, Lothar; Cafrune, Patricia; Cataldi, Angel; Cheong, Soonfatt; Diel, Roland; Ellermeier, Christopher; Evans, Jason T; Fauville-Dufaux, Maryse; Ferdinand, Séverine; de Viedma, Dario Garcia; Garzelli, Carlo; Gazzola, Lidia; Gomes, Harrison M; Guttierez, M Cristina; Hawkey, Peter M; van Helden, Paul D; Kadival, Gurujaj V; Kreiswirth, Barry N; Kremer, Kristin; Kubin, Milan; Kulkarni, Savita P; Liens, Benjamin; Lillebaek, Troels; Ly, Ho Minh; Martin, Carlos; Martin, Christian; Mokrousov, Igor; Narvskaïa, Olga; Ngeow, Yun Fong; Naumann, Ludmilla; Niemann, Stefan; Parwati, Ida; Rahim, Zeaur; Rasolofo-Razanamparany, Voahangy; Rasolonavalona, Tiana; Rossetti, M Lucia; Rüsch-Gerdes, Sabine; Sajduda, Anna; Samper, Sofia; Shemyakin, Igor G; Singh, Urvashi B; Somoskovi, Akos; Skuce, Robin A; van Soolingen, Dick; Streicher, Elisabeth M; Suffys, Philip N; Tortoli, Enrico; Tracevska, Tatjana; Vincent, Véronique; Victor, Tommie C; Warren, Robin M; Yap, Sook Fan; Zaman, Khadiza; Portaels, Françoise; Rastogi, Nalin; Sola, Christophe

    2006-01-01

    Background The Direct Repeat locus of the Mycobacterium tuberculosis complex (MTC) is a member of the CRISPR (Clustered regularly interspaced short palindromic repeats) sequences family. Spoligotyping is the widely used PCR-based reverse-hybridization blotting technique that assays the genetic diversity of this locus and is useful both for clinical laboratory, molecular epidemiology, evolutionary and population genetics. It is easy, robust, cheap, and produces highly diverse portable numerical results, as the result of the combination of (1) Unique Events Polymorphism (UEP) (2) Insertion-Sequence-mediated genetic recombination. Genetic convergence, although rare, was also previously demonstrated. Three previous international spoligotype databases had partly revealed the global and local geographical structures of MTC bacilli populations, however, there was a need for the release of a new, more representative and extended, international spoligotyping database. Results The fourth international spoligotyping database, SpolDB4, describes 1939 shared-types (STs) representative of a total of 39,295 strains from 122 countries, which are tentatively classified into 62 clades/lineages using a mixed expert-based and bioinformatical approach. The SpolDB4 update adds 26 new potentially phylogeographically-specific MTC genotype families. It provides a clearer picture of the current MTC genomes diversity as well as on the relationships between the genetic attributes investigated (spoligotypes) and the infra-species classification and evolutionary history of the species. Indeed, an independent Naïve-Bayes mixture-model analysis has validated main of the previous supervised SpolDB3 classification results, confirming the usefulness of both supervised and unsupervised models as an approach to understand MTC population structure. Updated results on the epidemiological status of spoligotypes, as well as genetic prevalence maps on six main lineages are also shown. Our results suggests

  20. The Air Force health study: an epidemiologic retrospective.

    PubMed

    Buffler, Patricia A; Ginevan, Michael E; Mandel, Jack S; Watkins, Deborah K

    2011-09-01

    In 1979, the U.S. Air Force announced that an epidemiologic study would be undertaken to determine whether the Air Force personnel involved in Operation Ranch Hand-the program responsible for herbicide spraying in Vietnam-had experienced adverse health effects as a result of that service. In January 1982 the Air Force Health Study (AFHS) protocol was approved and the 20 year matched cohort study consisting of independent mortality, morbidity and reproductive health components was initiated. This controversial study has been criticized regarding the study's potential scientific limitations as well as some of the administrative aspects of its conduct. Now, almost 30 years since the implementation of the AFHS and nearly a decade since the final follow up examinations, an appraisal of the study indicates that the results of the AFHS do not provide evidence of disease in the Ranch Hand veterans caused by their elevated levels of exposure to Agent Orange. PMID:21441038

  1. Serum Biomarkers of (Anti)Oxidant Status for Epidemiological Studies

    PubMed Central

    Jansen, Eugène; Ruskovska, Tatjana

    2015-01-01

    In this review, we disclose a selection of serum/plasma biomarkers of (anti)oxidant status related to nutrition, which can be used for measurements in large-scale epidemiological studies. From personal experience, we have come to the following proposal of a set of biomarkers for nutritional intake, (anti)oxidant status, and redox status. We have selected the individual antioxidant vitamins E and A, and the carotenoids which can be measured in large series by HPLC. In addition, vitamin C was selected, which can be measured by an auto-analyzer or HPLC. As a biomarker for oxidative stress, the ROM assay (reactive oxygen metabolites) was selected; for the redox status, the total thiol assay; and for the total antioxidant status the BAP assay (biological antioxidant potential). All of these biomarkers can be measured in large quantities by an auto-analyzer. Critical points in biomarker validation with respect to blood sampling, storage conditions, and measurements are discussed. With the selected biomarkers, a good set is presented for use in the risk assessment between nutrition and (chronic) diseases in large-scale epidemiological studies. Examples of the successful application of these biomarkers in large international studies are presented. PMID:26580612

  2. MODELING AN IRRITANT GAS PLUME FOR EPIDEMIOLOGIC STUDY

    PubMed Central

    Jani, Dev D.; Reed, David; Feigley, Charles E.

    2015-01-01

    Plume dispersion modeling systems are often used in assessing human exposures to chemical hazards for epidemiologic study. We modeled the 2005 Graniteville, South Carolina, 54,915 kg railcar chlorine release using both the Areal Locations of Hazardous Atmospheres (ALOHA) and Hazard Prediction and Assessment Capability (HPAC) plume modeling systems. We estimated the release rate by an engineering analysis combining semi-quantitative observations and fundamental physical principles. The use of regional meteorological conditions was validated by comparing concentration estimates generated by two source-location weather data sets. The HPAC model estimated a chlorine plume with 20 ppm outdoor concentrations up to 7 km downwind and 0.25 km upwind/downgrade. A comparative analysis of our two models showed that HPAC was the best candidate for use as a model system on which epidemiologic studies could be based after further model validation. Further validation studies are needed before individual exposure estimates can be reliable and the chlorine plume more definitively modeled. PMID:25772143

  3. First Molecular Epidemiological Study of Cutaneous Leishmaniasis in Libya

    PubMed Central

    Amro, Ahmad; Gashout, Aisha; Al-Dwibe, Hamida; Zahangir Alam, Mohammad; Annajar, Badereddin; Hamarsheh, Omar; Shubar, Hend; Schönian, Gabriele

    2012-01-01

    Background Cutaneous leishmaniasis (CL) is a major public health problem in Libya. The objective of this study was to investigate, for the first time, epidemiological features of CL outbreaks in Libya including molecular identification of parasites, the geographical distribution of cases and possible scenarios of parasite transmission. Methodology/Principal Findings We studied 450 patients that came from 49 areas distributed in 12 districts in north-west Libya. The patients' ages ranged from 9 months to 87 years (median age 25 years); 54% of the cases were males. Skin scrapings spotted on glass slides were collected for molecular identification of causative agent. The ribosomal internal transcribed spacer 1 (ITS1) was amplified and subsequently characterized by restriction fragment length polymorphism (RFLP) analysis. In total, 195 samples were successfully identified of which 148 (75.9%) were Leishmania major, and 47 (24.1%) Leishmania tropica. CL cases infected with L. major were found in all CL areas whereas L. tropica cases came mainly from Al Jabal Al Gharbi (46.4%), Misrata (17.8%) and Tarhuna districts (10.7%). A trend of seasonality was noticed for the infections with L. major which showed a clear peak between November and January, but was less pronounced for infections by L. tropica. Conclusion The first molecular study on CL in Libya revealed that the disease is caused by L. major and L. tropica and the epidemiological patterns in the different foci were the same as in other Mediterranean foci of CL. PMID:22724036

  4. Genetic epidemiology of gallbladder disease in Mexican Americans and cholesterol 7a-hydroxylase gene variation

    SciTech Connect

    Lin, J.P.; Hanis, C.L.; Boerwinkle, E.

    1994-09-01

    Among Mexican Americans the prevalence of gallbladder disease is markedly elevated. Previous data from both genetic admixture and family studies indicate that there is genetic component to the occurrence of gallbladder disease in Mexican Americans. However, prior to this study no formal genetic analysis of gallbladder disease had been carried out nor had any contributing gene been identified. The results of complex segregation analysis in a sample of 232 Mexican Americans with age- and gender-specific effects influencing the occurrence of gallbladder disease. The estimated frequency of the allele increasing susceptibility was 0.39. The lifetime probabilities that an individual will be affected by gallbladder disease were 1.0, 0.54, and 0.00 for females of genotypes {open_quotes}AA{close_quotes}, {open_quotes}Aa{close_quotes}, and {open_quotes}aa{close_quotes}, respectively, and 0.68, 0.30, and 0.00 for males, respectively. Human cholesterol 7a-hydroxylase is the rate-limiting enzyme in bile acid synthesis. The results of an association study in both a random sample and a matched case/control sample showed that there is a significant association between cholesterol 7a-hydroxylase gene variation and the occurrence of gallbladder disease in Mexican Americans males but not in females. For loci in the 5{prime}-end of the cholesterol 7a-hydroxylase gene, the frequency of the susceptibility alleles was twice as high in gallbladder disease patients compared to controls. The results of a linkage analysis provide evidence that the cholesterol 7a-hydroxylase gene and the inferred gallbladder disease gene are genetically linked.

  5. Study of Resource Recovery and Epidemiology in an Anaerobic Digester

    NASA Technical Reports Server (NTRS)

    Li, K. Y.; Cao, Song; Hunt, M. D.; Fu, Xuping

    1995-01-01

    Three 4-liter packed bed anaerobic digesters were fabricated and operated at 35 degrees C, pH around 7, and hydraulic retention time (HRT) of 20, 10 and 5 days to study the resource recovery and epidemiology in a controlled ecological life support system (CELSS). A simulated wastewater, consisted of shower water, clothwash water, dishwasher water, handwash water, and urine flush water was used as the feeding solution. Under steady-state operation, chemical oxygen demand (COD), total organic carbon (TOC), pH, nitrogen, phosphorus, and potassium wer monitored in the digester input and output solutions. The volume and the CH4/CO2 ratios in the biogas produced from the anaerobic digesters were measured. The results indicate about 90 percent of TOC is converted while only 5-8 percent of N-P-K are consumed in the digester. A multi-drug resistant strain of Salmonella choleraesuis was used as the indicator bacterium in the epidemiology study. The levels of Salmonella choleraesuis in the influent and the effluent wer determined and decimal decay rate constants, k(d), were estimated. The k(d) values were greater at higher initial doses than lower doses for the same HR, and greater for batch digestion (7.89/d) than for continuous digestion (4.28, 3.82, and 3.82/d for 20, 10, and 5 d HRT, respectively).

  6. Genetic risks and environmental surveillance: epidemiological aspects of monitoring industrial populations for environmental mutagens

    SciTech Connect

    Buffler, P.A.; Aase, J.M.

    1982-04-01

    As industrial populations are exposed to new chemicals and other agents in their work environment, it becomes increasingly important to be able to ascertain any associated genetic risks. The characteristics of a desirable surveillance system for deleterious genetic effects are outlined and the existing or proposed surveillance systems for industrial populations are reviewed against these criteria. At present, monitoring for reproductive loss and infertility seems to be the technique best suited for surveillance of industrial populations. However, monitoring techniques based on these events do not directly assess mutagenicity. Since fetal death and infertility are strongly, but not exclusively, correlated with mutation, these methods can be considered as an early-warning system to indicate when and where more definitive studies are needed.

  7. The Relationship Between Parkinson's Disease and Essential Tremor: Review of Clinical, Epidemiologic, Genetic, Neuroimaging and Neuropathological Data, and Data on the Presence of Cardinal Signs of Parkinsonism in Essential Tremor

    PubMed Central

    Jiménez-Jiménez, Félix Javier; Alonso-Navarro, Hortensia; García-Martín, Elena; Agúndez, José A. G.

    2012-01-01

    Background The possible relationship between essential tremor (ET) and Parkinson's disease (PD) has been controversial since the first description of PD. However, there is increasing evidence suggesting an overlap between these two disorders. The aim of this review is to examine the relationship between PD and ET, focusing on clinical, epidemiologic, genetic, neuroimaging, and neuropathological data, and the presence of cardinal parkinsonism symptoms in ET. Methods We conducted a PubMed search for articles published between 1966 and November 2011 regarding the relationship between ET and PD and the presence of postural tremor in PD patients; the presence of rest tremor, rigidity, and slowed movements in ET patients is reviewed. Results Clinical series, follow-up studies of ET patients, and case–control and genetic epidemiological studies indicate that ET is associated with increased risk for PD. Some neuroimaging studies and neuropathological reports suggest an association between the two diseases. ET patients show high prevalence of rest tremor, and at least seven studies described slowed movements (possibly related to cerebellar dysfunction and/or bradykinesia) in patients with ET. Discussion There is reasonable epidemiological and clinical evidence to support a link between ET and PD, although it is not clear what factors predict ET patient risk for developing PD or, more rarely, of PD patients developing ET. Future multicentric and multidisciplinary studies including epidemiological, clinical, neuroimaging, genetic, and neuropathological assessments are required to understand these associations. PMID:23439992

  8. Particulate matter and heart disease: Evidence from epidemiological studies

    SciTech Connect

    Peters, Annette . E-mail: peters@gsf.de

    2005-09-01

    The association between particulate matter and heart disease was noted in the mid-nineties of last century when the epidemiological evidence for an association between air pollution and hospital admissions due to cardiovascular disease accumulated and first hypotheses regarding the pathomechanism were formulated. Nowadays, epidemiological studies have demonstrated coherent associations between daily changes in concentrations of ambient particles and cardiovascular disease mortality, hospital admission, disease exacerbation in patients with cardiovascular disease and early physiological responses in healthy individuals consistent with a risk factor profile deterioration. In addition, evidence was found that annual average PM{sub 2.5} exposures are associated with increased risks for mortality caused by ischemic heart disease and dysrhythmia. Thereby, evidence is suggesting not only a short-term exacerbation of cardiovascular disease by ambient particle concentrations but also a potential role of particles in defining patients' vulnerability to acute coronary events. While this concept is consistent with the current understanding of the factors defining patients' vulnerability, the mechanisms and the time-scales on which the particle-induced vulnerability might operate are unknown.

  9. Blood pressure and interpersonal discrimination: systematic review of epidemiologic studies.

    PubMed

    Couto, Paulo Francisco; Goto, Janaina Brugnera; Bastos, João Luiz

    2012-10-01

    The relationship between blood pressure and discrimination has been recently investigated, and there are conflicting debates in literature devoted to the topic. The objective of this study was to update previous literature reviews on discrimination and blood pressure. A bibliographic search was conducted in PubMed between January/2000 and December/2010, including epidemiological studies, assessing the relationship between interpersonal discrimination and blood pressure/hypertension. The 22 studies included originated from the United States; 96% of them used the cross-sectional design with convenience sample, comprising, in 59% of the studies, exclusively Black participants. The Everyday Discrimination Scale and the Perceived Racism Scale were the most frequently used instruments, emphasizing lifetime or chronic/everyday racial/ethnic discrimination. In the 22 studies assessed, the association between discrimination and blood pressure/hypertension was assessed 50 times. Twenty results (40%) showed no association between them, and only 15 (30%) revealed global positive associations, of which 67% were statistically significant. Eight negative associations were also observed, suggesting that higher exposure to discrimination would be associated with lower blood pressure/hypertension. The studies did not consistently support the hypothesis that discrimination is associated with higher blood pressure. These findings can be partially attributed to the limitations of the studies, especially those related to the measurement of discrimination and of factors that might modify its association with outcomes. To establish discrimination as an epidemiological risk factor, more rigorous methodological strategies should be used, and the theoretical frameworks that postulate causal relationships between discrimination and blood pressure should be reviewed.

  10. Asymptomatic infection with American cutaneous leishmaniasis: epidemiological and immunological studies

    PubMed Central

    Andrade-Narvaez, Fernando J; Loría-Cervera, Elsy Nalleli; Sosa-Bibiano, Erika I; Van Wynsberghe, Nicole R

    2016-01-01

    American cutaneous leishmaniasis (ACL) is a major public health problem caused by vector-borne protozoan intracellular parasites from the genus Leishmania, subgenera Viannia and Leishmania. Asymptomatic infection is the most common outcome after Leishmania inoculation. There is incomplete knowledge of the biological processes explaining the absence of signs or symptoms in most cases while other cases present a variety of clinical findings. Most studies of asymptomatic infection have been conducted in areas of endemic visceral leishmaniasis. In contrast, asymptomatic ACL infection has been neglected. This review is focused on the following: (1) epidemiological studies supporting the existence of asymptomatic ACL infection and (2) immunological studies conducted to understand the mechanisms responsible for controlling the parasite and avoiding tissue damage. PMID:27759762

  11. Epidemiological and Genetic Data Supporting the Transmission of Ancylostoma ceylanicum among Human and Domestic Animals

    PubMed Central

    Ngui, Romano; Lim, Yvonne A. L.; Traub, Rebecca; Mahmud, Rohela; Mistam, Mohd Sani

    2012-01-01

    Background Currently, information on species-specific hookworm infection is unavailable in Malaysia and is restricted worldwide due to limited application of molecular diagnostic tools. Given the importance of accurate identification of hookworms, this study was conducted as part of an ongoing molecular epidemiological investigation aimed at providing the first documented data on species-specific hookworm infection, associated risk factors and the role of domestic animals as reservoirs for hookworm infections in endemic communities of Malaysia. Methods/Findings A total of 634 human and 105 domestic canine and feline fecal samples were randomly collected. The overall prevalence of hookworm in humans and animals determined via microscopy was 9.1% (95% CI = 7.0–11.7%) and 61.9% (95% CI = 51.2–71.2%), respectively. Multivariate analysis indicated that participants without the provision of proper latrine systems (OR = 3.5; 95% CI = 1.53–8.00; p = 0.003), walking barefooted (OR = 5.6; 95% CI = 2.91–10.73; p<0.001) and in close contact with pets or livestock (OR = 2.9; 95% CI = 1.19–7.15; p = 0.009) were more likely to be infected with hookworms. Molecular analysis revealed that while most hookworm-positive individuals were infected with Necator americanus, Ancylostoma ceylanicum constituted 12.8% of single infections and 10.6% mixed infections with N. americanus. As for cats and dogs, 52.0% were positive for A. ceylanicum, 46.0% for Ancylostoma caninum and 2.0% for Ancylostoma braziliense and all were single infections. Conclusion This present study provided evidence based on the combination of epidemiological, conventional diagnostic and molecular tools that A. ceylanicum infection is common and that its transmission dynamic in endemic areas in Malaysia is heightened by the close contact of human and domestic animal (i.e., dogs and cats) populations. PMID:22347515

  12. Genetic Association Studies in Lumbar Disc Degeneration: A Systematic Review

    PubMed Central

    Eskola, Pasi J.; Lemmelä, Susanna; Kjaer, Per; Solovieva, Svetlana; Männikkö, Minna; Tommerup, Niels; Lind-Thomsen, Allan; Husgafvel-Pursiainen, Kirsti; Cheung, Kenneth M. C.; Chan, Danny

    2012-01-01

    Objective Low back pain is associated with lumbar disc degeneration, which is mainly due to genetic predisposition. The objective of this study was to perform a systematic review to evaluate genetic association studies in lumbar disc degeneration as defined on magnetic resonance imaging (MRI) in humans. Methods A systematic literature search was conducted in MEDLINE, MEDLINE In-Process, SCOPUS, ISI Web of Science, The Genetic Association Database and The Human Genome Epidemiology Network for information published between 1990–2011 addressing genes and lumbar disc degeneration. Two investigators independently identified studies to determine inclusion, after which they performed data extraction and analysis. The level of cumulative genetic association evidence was analyzed according to The HuGENet Working Group guidelines. Results Fifty-two studies were included for review. Forty-eight studies reported at least one positive association between a genetic marker and lumbar disc degeneration. The phenotype definition of lumbar disc degeneration was highly variable between the studies and replications were inconsistent. Most of the associations presented with a weak level of evidence. The level of evidence was moderate for ASPN (D-repeat), COL11A1 (rs1676486), GDF5 (rs143383), SKT (rs16924573), THBS2 (rs9406328) and MMP9 (rs17576). Conclusions Based on this first extensive systematic review on the topic, the credibility of reported genetic associations is mostly weak. Clear definition of lumbar disc degeneration phenotypes and large population-based cohorts are needed. An international consortium is needed to standardize genetic association studies in relation to disc degeneration. PMID:23185509

  13. Epidemiological studies of the respiratory effects of air pollution.

    PubMed

    Lebowitz, M D

    1996-05-01

    Environmental epidemiological studies of the health effects of air pollution have been major contributors to the understanding of such effects. The chronic effects of atmospheric pollutants have been studied, but, except for the known respiratory effects of particulate matter (PM), they have not been studied conclusively. There are ongoing studies of the chronic effects of certain pollutant classes, such as ozone, acid rain, airborne toxics, and the chemical form of PM (including diesel exhaust). Acute effects on humans due to outdoor and indoor exposures to several gases/fumes and PM have been demonstrated in epidemiological studies. However, the effects of these environmental factors on susceptible individuals are not known conclusively. These acute effects are especially important because they increase the human burden of minor illnesses, increase disability, and are thought to decrease productivity. They may be related to the increased likelihood of chronic disease as well. Further research is needed in this latter area, to determine the contributions of the time-related activities of individuals in different microenvironments (outdoors, in homes, in transit). Key elements of further studies are the assessment of total exposure to the different pollutants (occurring from indoor and outdoor source) and the interactive effects of pollutants. Major research areas include determination of the contributions of indoor sources and of vehicle emissions to total exposure, how to measure such exposures, and how to measure human susceptibility and responses (including those at the cellular and molecular level). Biomarkers of exposures, doses and responses, including immunochemicals, biochemicals and deoxyribonucleic acid (DNA) adducts, are beginning to promote some basic knowledge of exposure-response, especially the mechanisms. These will be extremely useful additions to standard physiological, immunological, and clinical instruments, and the understanding of biological

  14. Epidemiology of Down Syndrome

    ERIC Educational Resources Information Center

    Sherman, Stephanie L.; Allen, Emily G.; Bean, Lora H.; Freeman, Sallie B.

    2007-01-01

    Down syndrome (DS) is the most commonly identified genetic form of mental retardation and the leading cause of specific birth defects and medical conditions. Traditional epidemiological studies to determine the prevalence, cause, and clinical significance of the syndrome have been conducted over the last 100 years. DS has been estimated to occur…

  15. Epidemiologic studies of the human microbiome and cancer

    PubMed Central

    Vogtmann, Emily; Goedert, James J

    2016-01-01

    The human microbiome, which includes the collective genome of all bacteria, archaea, fungi, protists, and viruses found in and on the human body, is altered in many diseases and may substantially affect cancer risk. Previously detected associations of individual bacteria (e.g., Helicobacter pylori), periodontal disease, and inflammation with specific cancers have motivated studies considering the association between the human microbiome and cancer risk. This short review summarises microbiome research, focusing on published epidemiological associations with gastric, oesophageal, hepatobiliary, pancreatic, lung, colorectal, and other cancers. Large, prospective studies of the microbiome that employ multidisciplinary laboratory and analysis methods, as well as rigorous validation of case status, are likely to yield translational opportunities to reduce cancer morbidity and mortality by improving prevention, screening, and treatment. PMID:26730578

  16. How can epidemiological studies contribute to understanding autism spectrum disorders?

    PubMed

    Honda, Hideo

    2013-02-01

    More and more studies on the frequency of autism spectrum disorders (ASD) have been published recently, most of which show the increase in prevalence data. In this review, the author pointed out factors and parameters to be considered in analyzing frequency data, i.e., the enlargement of the concept of autism, prevalence and incidence, accuracy and precision in the initial screening, and the effect of the "vaccine debate". The proportion of high-functioning ASD has been growing higher and higher due to better recognition in the last few years, and the apparent increase might still be the tip of an iceberg. Future epidemiological studies should include themes on diversity of the longitudinal course and re-conceptualization of ASD by dimensional diagnosis. PMID:22766241

  17. Epidemiologic studies of the human microbiome and cancer.

    PubMed

    Vogtmann, Emily; Goedert, James J

    2016-02-01

    The human microbiome, which includes the collective genome of all bacteria, archaea, fungi, protists, and viruses found in and on the human body, is altered in many diseases and may substantially affect cancer risk. Previously detected associations of individual bacteria (e.g., Helicobacter pylori), periodontal disease, and inflammation with specific cancers have motivated studies considering the association between the human microbiome and cancer risk. This short review summarises microbiome research, focusing on published epidemiological associations with gastric, oesophageal, hepatobiliary, pancreatic, lung, colorectal, and other cancers. Large, prospective studies of the microbiome that employ multidisciplinary laboratory and analysis methods, as well as rigorous validation of case status, are likely to yield translational opportunities to reduce cancer morbidity and mortality by improving prevention, screening, and treatment.

  18. Ultraviolet radiation and the eye: an epidemiologic study.

    PubMed Central

    Taylor, H R

    1989-01-01

    Circumstantial evidence from biochemical, animal, and epidemiologic studies suggests an association between exposure to UV-B radiation (290 nm to 320 nm) and cataract. Such an association had not been proven because it had not been possible to quantify ocular UV-B exposure of individuals or to reliably grade the type and severity of cataract in field studies. We undertook an epidemiologic survey of cataract among 838 watermen who work on the Chesapeake Bay. Their individual ocular UV-B exposure was quantified for each year of life over the age of 16, on the basis of a detailed occupational history combined with laboratory and field measurements of ocular UV-B exposure. Cataracts were graded by both type and severity through clinical and photographic means. SMD changes were ascertained by fundal photography. A general medical history was taken to discover potentially confounding factors. This study showed that people with cortical lens opacities had a 21% higher UV-B exposure at each year of life than people without these opacities. A doubling in lifetime UV-B exposure led to a 60% increase in the risk of cortical cataract, and those with a high annual UV-B exposure increased their risk of cortical cataract over threefold. Corneal changes, namely pterygium and CDK, were also strongly associated with high UV-B exposure. No association was found between nuclear lens opacities or macular degeneration and UV-B exposure. This study also indicated several simple, practical measures, such as wearing spectacles or a hat, that effectively protect the eye from UV-B exposure. Thus it is easily within the power of individuals to protect their eyes from excessive UV-B exposure and reduce their risk of cortical cataract. A program of public education in this area could be a cost-effective means of reducing this important disease. PMID:2562534

  19. Epidemiology, Pathology, and Genetics of Histiocytic Sarcoma in the Bernese Mountain Dog Breed

    PubMed Central

    Abadie, Jérôme; Hédan, Benoit; Cadieu, Edouard; De Brito, Clotilde; Devauchelle, Patrick; Bourgain, Catherine; Parker, Heidi G.; Vaysse, Amaury; Margaritte-Jeannin, Patricia; Galibert, Francis; Ostrander, Elaine A.

    2009-01-01

    Histiocytic sarcoma (HS) refers to a highly aggressive and frequently disseminated neoplastic disease belonging to the class of canine histiocytic proliferative disorders. Disseminated HS (previously called malignant histiocytosis) is highly breed specific, with Bernese mountain dogs (BMDs), rottweilers, and retrievers having a high prevalence with a frequency of approximately 25% in the BMD breed. We collected DNA samples and clinical information from 800 BMDs, of which 200 are affected by HS. To better characterize the physiopathology and epidemiology, an in-depth analysis of 89 BMD cases has been performed. The mean age of onset was 6.5 years, males and females being equally affected. The clinical features, biochemical parameters, and pathological features have been determined. The life span after diagnosis has been estimated to be 49 days. A large BMD pedigree of 327 dogs, 121 of which are affected, was assembled. Using a subset of 160 BMDs, encompassing 21 complete sibships, we now propose an oligogenic transmission mode of the disease. Whole-genome linkage scans as well as association studies using a case/control analysis, in parallel with expression profiling of neoplastic versus normal histiocytes, are all underway. Altogether, these complementary approaches are expected to localize the genes for HS in the BMD, leading to advances in our knowledge of histiocyte diseases in dogs and humans. PMID:19531730

  20. Sandfly-borne phleboviruses of Eurasia and Africa: epidemiology, genetic diversity, geographic range, control measures.

    PubMed

    Alkan, Cigdem; Bichaud, Laurence; de Lamballerie, Xavier; Alten, Bulent; Gould, Ernest A; Charrel, Rémi N

    2013-10-01

    Sandfly-borne phleboviruses may cause a transient febrile illness (sandfly fever) or more severe neuroinvasive disease. In the Old World, they are vectored by phlebotomine flies, which are widely distributed in the Mediterranean basin, North Africa, the Indian subcontinent, the Middle East and central Asia. High seroprevalence rates have been recorded in humans and domestic animals in areas where sandflies are present. Most published studies have focused on phlebovirus infections of travelers and of soldiers stationed in endemic areas, but the health impact on local populations should not be underestimated, as seroprevalence studies indicate massive circulation of these viruses, even if disease is seldom documented. Except for Toscana virus, which shows a marked neurotropism and is a leading cause of aseptic meningitis in endemic regions, phlebovirus infections are inadequately considered by physicians and are generally underestimated. However, several properties of these viruses suggest that they will extend their geographic range. First, changes in the areas occupied by sandflies as a result of climate change have a direct impact on the epidemiology of associated human and animal diseases. Second, phleboviruses exhibit a high mutation rate, and their tri-segmented genome is prone to reassortment and recombination. Third, distinct virus strains can be transmitted by the same arthropod species. Recent studies have documented the distribution of sandfly-borne phleboviruses in Western Europe, but data for Eastern Europe, the Middle East and Africa are very limited. With the goal of filling knowledge gaps and planning new research programs, we have examined available information and present it as a comprehensive review, with a specific focus on understudied regions. We also discuss the need to conduct studies aimed at developing new antiviral drugs and vaccines.

  1. Study Identifies Genetic Subtypes of Crohn's Disease

    MedlinePlus

    ... medlineplus.gov/news/fullstory_161499.html Study Identifies Genetic Subtypes of Crohn's Disease Findings may help explain ... disease appears to have at least two distinct genetic subtypes, which could explain why the condition is ...

  2. Studies in genetic discrimination. Final progress report

    SciTech Connect

    Not Available

    1994-06-01

    We have screened 1006 respondents in a study of genetic discrimination. Analysis of these responses has produced evidence of the range of institutions engaged in genetic discrimination and demonstrates the impact of this discrimination on the respondents to the study. We have found that both ignorance and policy underlie genetic discrimination and that anti-discrimination laws are being violated.

  3. Complex approaches to study complex trait genetics in multiple sclerosis.

    PubMed

    Kálmán, Bernadette

    2014-09-30

    Multiple sclerosis (MS) is a complex trait disorder defined by several genes and their interactions with environmental factors. A comprehensive exploration of the susceptibility variants had not been feasible until recently when new developments in biotechnology and bioinformatics made possible sequencing of the whole human genome, cataloguing of nucleotide variants and alignments of these variants in haplotypes. Earlier observations from epidemiological, candidate gene and linkage studies provided ample evidence to support a complex genetic determination of MS. New biotechnology and bioinformatics resources have been recently applied to further successful explorations of the disease. These efforts were paralleled by more careful and reliable ascertainments of disease phenotypes, collaborations among specialized centers to generate sufficient sample size and involvement of clinician-scientists capable of working both on the clinical and scientific study sides. Data obtained from the whole genome association studies (GWAS) elevated our understanding of MS genetics to a new level by identifying an extensive list of genetic determinants. Pathway analyses of MS-associated variants provided evidence to support the immune etiology of the disease. Future research will likely explore how environmental factors interact with the genome, and contribute to the abnormal immune activation and inflammation. This review summarizes the outcomes of MS genetic explorations including those of recent GWAS, and highlights practical consequences of genetic and genomic studies by pointing out as to how the derived data facilitate further elucidation of MS pathogenesis. A better understanding of disease processes is necessary for future advancements in therapeutics and the development of disease prevention strategies.

  4. Complete genome sequence of hypervirulent and outbreak-associated Acinetobacter baumannii strain LAC-4: epidemiology, resistance genetic determinants and potential virulence factors

    PubMed Central

    Ou, Hong-Yu; Kuang, Shan N.; He, Xinyi; Molgora, Brenda M.; Ewing, Peter J.; Deng, Zixin; Osby, Melanie; Chen, Wangxue; Xu, H. Howard

    2015-01-01

    Acinetobacter baumannii is an important human pathogen due to its multi-drug resistance. In this study, the genome of an ST10 outbreak A. baumannii isolate LAC-4 was completely sequenced to better understand its epidemiology, antibiotic resistance genetic determinants and potential virulence factors. Compared with 20 other complete genomes of A. baumannii, LAC-4 genome harbors at least 12 copies of five distinct insertion sequences. It contains 12 and 14 copies of two novel IS elements, ISAba25 and ISAba26, respectively. Additionally, three novel composite transposons were identified: Tn6250, Tn6251 and Tn6252, two of which contain resistance genes. The antibiotic resistance genetic determinants on the LAC-4 genome correlate well with observed antimicrobial susceptibility patterns. Moreover, twelve genomic islands (GI) were identified in LAC-4 genome. Among them, the 33.4-kb GI12 contains a large number of genes which constitute the K (capsule) locus. LAC-4 harbors several unique putative virulence factor loci. Furthermore, LAC-4 and all 19 other outbreak isolates were found to harbor a heme oxygenase gene (hemO)-containing gene cluster. The sequencing of the first complete genome of an ST10 A. baumannii clinical strain should accelerate our understanding of the epidemiology, mechanisms of resistance and virulence of A. baumannii. PMID:25728466

  5. [Polish Multicenter Study on Diabetes Epidemiology (PMSDE)--1998-2000].

    PubMed

    Szybiński, Z

    2001-09-01

    increasing a burden of patients, theirs families, society and health care system. Within PMSDE programme elaboration of the model for calculation the direct costs about of diabetes and burden in terms of years of life lost using DALY measure was performed (K. Kissimova-Skarbek). Average diabetes type 1 patients costs 7 times and type 2 over 3 times higher than average health care cost and 95% of total time lost due to disability is caused by diabetes type 2. Therefor primary and secondary prevention of diabetes typ 2 have highest priority among strategic preventive targets. The Review Conference held in Warsaw at 24-25 February 2001 in the presence of WHO Experts formulated the recommendations focused on: 1. Elaboration of high risk strategy for early diagnosis of unknown diabetes type 2 based on the 2-hours OGTT (WHO 1985) 2. Continuation of the epidemiologic study in diabetes 3. Instituting the professional post for diabetes educator on the specialized and primary health care levels. 4. Further research are recommended for evaluation of the role of fasting glycemia and hyperinsulinemia as predictors and risk factors of diabetes type 2, for development of preventive models in diabetes type 2 and for development of the economical models to asses the costs of diabetes (Recommendations).

  6. Radiation epidemiology and recent paediatric computed tomography studies.

    PubMed

    Boice, J D

    2015-06-01

    Recent record-linkage studies of cancer risk following computed tomography (CT) procedures among children and adolescents under 21 years of age must be interpreted with caution. The reasons why the examinations were performed were not known, and the dosimetric approaches did not include individual dose reconstructions or account for the possibility for missed examinations. The recent report (2013) on children by the United Nations Scientific Committee on the Effects of Atomic Radiation concluded that the associations may have resulted from confounding by indication (also called 'reverse causation'), and not radiation exposure. The reported cancer associations may very well have been related to the patients' underlying health conditions that prompted the examinations. Reverse causation has been observed in other epidemiological investigations, such as a Swedish study of thyroid cancer risk following I-131 scintillation imaging scans, and in studies of brain cancer risk following Thorotrast for cerebral angiography. Epidemiological patterns reported in the CT studies were also inconsistent with the world's literature. For example, in a UK study, teenagers had a higher risk of brain tumour than young children; in an Australian study, cancers not previously linked to radiation were significantly elevated; and in a Taiwanese study, the risk of benign tumours decreased with age at the time of CT examination. In all studies, solid tumours appeared much earlier than previously reported. Remarkably, in the Australian study, brain cancer excesses were seen regardless of whether or not the CT was to the head, i.e. a significant excess was reported for CT examinations of the abdomen and extremities, which involved no radiation exposure to the brain. In the UK study, the significance of the 'leukaemia' finding was only because myelodysplastic syndrome was added to the category, and there was no significance for leukaemia alone. Without knowledge of why CT examinations were

  7. An epidemiological study of lens opacities among steel workers

    PubMed Central

    Wallace, J.; Sweetnam, P. M.; Warner, C. G.; Graham, P. A.; Cochrane, A. L.

    1971-01-01

    Wallace, J., Sweetnam, P. M., Warner, C. G., Graham, P. A., and Cochrane, A. L. (1971).Brit. J. industr. Med.,28, 265-271. An epidemiological study of lens opacities among steel workers. To investigate the relationship between the prevalence of cataract and heat exposure, two groups of steel workers, differing widely in their heat exposure, were examined. Estimates of heat exposure were based on detailed industrial histories and (a) subjective estimates of heat exposure associated with various occupations and (b) actual measurements. Only two cases of cataract were found that would be generally accepted as `occupational' in origin, but a higher prevalence of the common form of cataract was found in the heat-exposed group than in the non-exposed group. PMID:5557847

  8. Probabilistic Approaches to Better Quantifying the Results of Epidemiologic Studies

    PubMed Central

    Gustafson, Paul; McCandless, Lawrence C.

    2010-01-01

    Typical statistical analysis of epidemiologic data captures uncertainty due to random sampling variation, but ignores more systematic sources of variation such as selection bias, measurement error, and unobserved confounding. Such sources are often only mentioned via qualitative caveats, perhaps under the heading of ‘study limitations.’ Recently, however, there has been considerable interest and advancement in probabilistic methodologies for more integrated statistical analysis. Such techniques hold the promise of replacing a confidence interval reflecting only random sampling variation with an interval reflecting all, or at least more, sources of uncertainty. We survey and appraise the recent literature in this area, giving some prominence to the use of Bayesian statistical methodology. PMID:20617044

  9. Combining Telomerase Reverse Transcriptase Genetic Variant rs2736100 with Epidemiologic Factors in the Prediction of Lung Cancer Susceptibility

    PubMed Central

    Wang, Xu; Ma, Kewei; Chi, Lumei; Cui, Jiuwei; Jin, Lina; Hu, Ji-Fan; Li, Wei

    2016-01-01

    Genetic variants from a considerable number of susceptibility loci have been identified in association with cancer risk, but their interaction with epidemiologic factors in lung cancer remains to be defined. We sought to establish a forecasting model for identifying individuals with high-risk of lung cancer by combing gene single-nucleotide polymorphisms with epidemiologic factors. Genotyping and clinical data from 500 lung cancer cases and 500 controls were used for developing the logistic regression model. We found that lung cancer was associated with telomerase reverse transcriptase (TERT) rs2736100 single-nucleotide polymorphism. The TERT rs2736100 model was still significantly associated with lung cancer risk when combined with environmental and lifestyle factors, including lower education, lower BMI, COPD history, heavy cigarettes smoking, heavy cooking emission, and dietary factors (over-consumption of meat and deficiency in fish/shrimp, vegetables, dairy products, and soybean products). These data suggest that combining TERT SNP and epidemiologic factors may be a useful approach to discriminate high and low-risk individuals for lung cancer. PMID:27162544

  10. Failure to initiate early insulin therapy – A risk factor for diabetic retinopathy in insulin users with Type 2 diabetes mellitus: Sankara Nethralaya-Diabetic Retinopathy Epidemiology and Molecular Genetics Study (SN-DREAMS, Report number 35)

    PubMed Central

    Gupta, Aditi; Delhiwala, Kushal S; Raman, Rajiv P G; Sharma, Tarun; Srinivasan, Sangeetha; Kulothungan, Vaitheeswaran

    2016-01-01

    Context: Insulin users have been reported to have a higher incidence of diabetic retinopathy (DR). Aim: The aim was to elucidate the factors associated with DR among insulin users, especially association between duration, prior to initiating insulin for Type 2 diabetes mellitus (DM) and developing DR. Materials and Methods: Retrospective cross-sectional observational study included 1414 subjects having Type 2 DM. Insulin users were defined as subjects using insulin for glycemic control, and insulin nonusers as those either not using any antidiabetic treatment or using diet control or oral medications. The duration before initiating insulin after diagnosis was calculated by subtracting the duration of insulin usage from the duration of DM. DR was clinically graded using Klein's classification. SPSS (version 9.0) was used for statistical analysis. Results: Insulin users had more incidence of DR (52.9% vs. 16.3%, P < 0.0001) and sight threatening DR (19.1% vs. 2.4%, P < 0.0001) in comparison to insulin nonusers. Among insulin users, longer duration of DM (odds ratio [OR] 1.12, 95% confidence interval [CI] 1.00–1.25, P = 0.044) and abdominal obesity (OR 1.15, 95% CI 1.02–1.29, P = 0.021) was associated with DR. The presence of DR was significantly associated with longer duration (≥5 years) prior to initiating insulin therapy, overall (38.0% vs. 62.0%, P = 0.013), and in subjects with suboptimal glycemic control (32.5% vs. 67.5%, P = 0.022). Conclusions: The presence of DR is significantly associated with longer duration of diabetes (>5 years) and sub-optimal glycemic control (glycosylated hemoglobin <7.0%). Among insulin users, abdominal obesity was found to be a significant predictor of DR; DR is associated with longer duration prior to initiating insulin therapy in Type 2 DM subjects with suboptimal glycemic control. PMID:27488152

  11. Genetics and epidemiology of gallbladder disease in New World native peoples.

    PubMed Central

    Weiss, K M; Ferrell, R E; Hanis, C L; Styne, P N

    1984-01-01

    Native peoples of the New World, including Amerindians and admixed Latin Americans such as Mexican-Americans, are highly susceptible to diseases of the gallbladder. These include cholesterol cholelithiasis (gallstones) and its complications, as well as cancer of the gallbladder. Although there is clearly some necessary dietary or other environmental risk factor involved, the pattern of disease prevalence is geographically associated with the distribution of genes of aboriginal Amerindian origin, and levels of risk generally correspond to the degree of Amerindian admixture. This pattern differs from that generally associated with Westernization, which suggests a gene-environment interaction, and that within an admixed population there is a subset whose risk is underestimated when admixture is ignored. The risk that an individual of a susceptible New World genotype will undergo a cholecystectomy by age 85 can approach 40% in Mexican-American females, and their risk of gallbladder cancer can reach several percent. These are heretofore unrecognized levels of risk, especially of the latter, because previous studies have not accounted for admixture or for the loss of at-risk individuals due to cholecystectomy. A genetic susceptibility may, thus, be as "carcinogenic" in New World peoples as any known major environmental exposure; yet, while the risk has a genetic basis, its expression as gallbladder cancer is so delayed as to lead only very rarely to multiply-affected families. Estimates in this paper are derived in part from two studies of Mexican-Americans in Starr County and Laredo, Texas. PMID:6517051

  12. Genetics and epidemiology of gallbladder disease in New World native peoples.

    PubMed

    Weiss, K M; Ferrell, R E; Hanis, C L; Styne, P N

    1984-11-01

    Native peoples of the New World, including Amerindians and admixed Latin Americans such as Mexican-Americans, are highly susceptible to diseases of the gallbladder. These include cholesterol cholelithiasis (gallstones) and its complications, as well as cancer of the gallbladder. Although there is clearly some necessary dietary or other environmental risk factor involved, the pattern of disease prevalence is geographically associated with the distribution of genes of aboriginal Amerindian origin, and levels of risk generally correspond to the degree of Amerindian admixture. This pattern differs from that generally associated with Westernization, which suggests a gene-environment interaction, and that within an admixed population there is a subset whose risk is underestimated when admixture is ignored. The risk that an individual of a susceptible New World genotype will undergo a cholecystectomy by age 85 can approach 40% in Mexican-American females, and their risk of gallbladder cancer can reach several percent. These are heretofore unrecognized levels of risk, especially of the latter, because previous studies have not accounted for admixture or for the loss of at-risk individuals due to cholecystectomy. A genetic susceptibility may, thus, be as "carcinogenic" in New World peoples as any known major environmental exposure; yet, while the risk has a genetic basis, its expression as gallbladder cancer is so delayed as to lead only very rarely to multiply-affected families. Estimates in this paper are derived in part from two studies of Mexican-Americans in Starr County and Laredo, Texas. PMID:6517051

  13. Genetic studies of the Roma (Gypsies): a review

    PubMed Central

    Kalaydjieva, Luba; Gresham, David; Calafell, Francesc

    2001-01-01

    Background Data provided by the social sciences as well as genetic research suggest that the 8-10 million Roma (Gypsies) who live in Europe today are best described as a conglomerate of genetically isolated founder populations. The relationship between the traditional social structure observed by the Roma, where the Group is the primary unit, and the boundaries, demographic history and biological relatedness of the diverse founder populations appears complex and has not been addressed by population genetic studies. Results Recent medical genetic research has identified a number of novel, or previously known but rare conditions, caused by private founder mutations. A summary of the findings, provided in this review, should assist diagnosis and counselling in affected families, and promote future collaborative research. The available incomplete epidemiological data suggest a non-random distribution of disease-causing mutations among Romani groups. Conclusion Although far from systematic, the published information indicates that medical genetics has an important role to play in improving the health of this underprivileged and forgotten people of Europe. Reported carrier rates for some Mendelian disorders are in the range of 5 -15%, sufficient to justify newborn screening and early treatment, or community-based education and carrier testing programs for disorders where no therapy is currently available. To be most productive, future studies of the epidemiology of single gene disorders should take social organisation and cultural anthropology into consideration, thus allowing the targeting of public health programs and contributing to the understanding of population structure and demographic history of the Roma. PMID:11299048

  14. Cycloplegic refraction is the gold standard for epidemiological studies.

    PubMed

    Morgan, Ian G; Iribarren, Rafael; Fotouhi, Akbar; Grzybowski, Andrzej

    2015-09-01

    Many studies on children have shown that lack of cycloplegia is associated with slight overestimation of myopia and marked errors in estimates of the prevalence of emmetropia and hyperopia. Non-cycloplegic refraction is particularly problematic for studies of associations with risk factors. The consensus around the importance of cycloplegia in children left undefined at what age, if any, cycloplegia became unnecessary. It was often implicitly assumed that cycloplegia is not necessary beyond childhood or early adulthood, and thus, the protocol for the classical studies of refraction in older adults did not include cycloplegia. Now that population studies of refractive error are beginning to fill the gap between schoolchildren and older adults, whether cycloplegia is required for measuring refractive error in this age range, needs to be defined. Data from the Tehran Eye Study show that, without cycloplegia, there are errors in the estimation of myopia, emmetropia and hyperopia in the age range 20-50, just as in children. Similar results have been reported in an analysis of data from the Beaver Dam Offspring Eye Study. If the only important outcome measure of a particular study is the prevalence of myopia, then cycloplegia may not be crucial in some cases. But, without cycloplegia, measurements of other refractive categories as well as spherical equivalent are unreliable. In summary, the current evidence suggests that cycloplegic refraction should be considered as the gold standard for epidemiological studies of refraction, not only in children, but in adults up to the age of 50.

  15. Epidemiology, prevalence, and genetic characterization of Toxoplasma gondii in felids and other wildlife from Minnesota, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Little is known of the epidemiology of toxoplasmosis in Minnesota. Here, we evaluated T. gondii infection in 50 bobcats (Lynx rufus) from the wild and 75 animals on/near 10 cattle farms. Antibodies to T. gondii were assayed in serum samples or tissue fluids by the modified agglutination test (MAT, c...

  16. Canine Dirofilaria Infections in Two Uninvestigated Areas of Serbia: Epidemiological and Genetic Aspects

    PubMed Central

    Tasić, Aleksandar; Tasić-Otašević, Suzana; Gabrielli, Simona; Miladinović-Tasić, Nataša; Ignjatović, Aleksandra; Đorđević, Jovana; Dimitrijević, Sanda

    2012-01-01

    Abstract In 2009 canine filarial infections were investigated in two northern areas of Serbia (Pančevo and Veliko Gradište), applying morphometry, biochemical staining, and immunological kit to detect Dirofilaria immitis antigens, and two home-made ELISAs to detect antibodies to D. repens and D. immitis somatic/metabolic polyproteins. Moreover, molecular tools were applied to analyze the phylogenetic relationships of the isolates. The microfilariae detected in 21/122 dogs (17.2%) were identified as D. repens (n=21) and D. immitis (n=2). D. immitis antigens were found in another 13 animals with occult infection. All of the 15 heartworm-positive dogs also had antibodies to this parasite, which were detected in another 13 subjects, indicating an overall D. immitis seroprevalence rate of 22.9%. Serology for D. repens revealed evidence of antibodies in 42.6% of the dogs, but was negative for 4 microfilaremic dogs. As for the two different areas, the prevalence of microfilariae and/or D. immitis antigens, mainly due to D. repens microfilaremic animals, was not significantly higher in Veliko Gradište (33.3%) than in Pančevo (22%). However, serology showed a different epidemiological picture. Heartworm infection occurred more often in both areas, and antibodies to dirofilarial nematodes were detected in 72.9% of dogs living in Pančevo, a rate higher than in those living in Veliko Gradište (57.1%). No risk factors for infection were found, confirming the uselessness of prophylactic drugs against D. repens, and suggesting the presence in these areas of sunrise- or sunset-biting mosquitoes as important vectors. The results indicate the need for both appropriate entomological studies and further research on the intra-species variability shown by D. repens. PMID:23127188

  17. Genetic studies in primary gout

    PubMed Central

    Alvsaker, J. O.

    1968-01-01

    The plasma levels of the urate-binding α1-α2-globulin, as determined by its urate-binding capacity, have been recorded in 19 individuals from two gouty kindreds. A significantly reduced binding capacity, accounting for 13-30% of the mean value obtained in healthy, unrelated control subjects, was found in all cases of gout and in the single case of essential hyperuricemia included in the present study. In addition, six apparently healthy members of one of these kindreds also exhibited this characteristic. The distribution of the characteristic in three subsequent generations from this kindred further supported the hypothesis that the reduced binding capacity was inherited as an autosomal trait for which affected subjects were heterozygous. Based on the present observation, the mechanisms of inheritance in primary gout are discussed with special emphasis on the possible cooperation of genetic and environmental factors. Images PMID:4172458

  18. Strategies for epidemiologic studies of lead in bone in occupationally exposed populations

    SciTech Connect

    Landrigan, P.J. )

    1991-02-01

    Lead exposure is widespread among industrial populations in the US. X-ray fluorescence (XRF) analysis of the lead content of bone offers a promising approach to acquisition of individualized data on chronic lead absorption in occupationally exposed populations. Dosimetric data obtained by XRF will permit accurate definition of dose-response relationships for such chronic consequences of lead exposure as central and peripheral neurologic impairment, renal disease, hypertension, and possibly reproductive dysfunction. Additionally, data on bone lead contect obtained by XRF will permit validation of models describing the body lead burden and will allow direct assessment of the efficacy of therapeutic chelation. XRF data may also permit assessment of the possible role of genetic polymorphism of the enzyme delta-aminolevulinic dehydrase as a determinant of the pharmacokinetics and toxicity of lead. In both cross-sectional and prospective epidemiologic studies of body lead burden in occupationally exposed populations, the K-XRF instrument appears to be the technology of choice.

  19. Polygenic Epidemiology

    PubMed Central

    2016-01-01

    ABSTRACT Much of the genetic basis of complex traits is present on current genotyping products, but the individual variants that affect the traits have largely not been identified. Several traditional problems in genetic epidemiology have recently been addressed by assuming a polygenic basis for disease and treating it as a single entity. Here I briefly review some of these applications, which collectively may be termed polygenic epidemiology. Methodologies in this area include polygenic scoring, linear mixed models, and linkage disequilibrium scoring. They have been used to establish a polygenic effect, estimate genetic correlation between traits, estimate how many variants affect a trait, stratify cases into subphenotypes, predict individual disease risks, and infer causal effects using Mendelian randomization. Polygenic epidemiology will continue to yield useful applications even while much of the specific variation underlying complex traits remains undiscovered. PMID:27061411

  20. Polygenic Epidemiology.

    PubMed

    Dudbridge, Frank

    2016-05-01

    Much of the genetic basis of complex traits is present on current genotyping products, but the individual variants that affect the traits have largely not been identified. Several traditional problems in genetic epidemiology have recently been addressed by assuming a polygenic basis for disease and treating it as a single entity. Here I briefly review some of these applications, which collectively may be termed polygenic epidemiology. Methodologies in this area include polygenic scoring, linear mixed models, and linkage disequilibrium scoring. They have been used to establish a polygenic effect, estimate genetic correlation between traits, estimate how many variants affect a trait, stratify cases into subphenotypes, predict individual disease risks, and infer causal effects using Mendelian randomization. Polygenic epidemiology will continue to yield useful applications even while much of the specific variation underlying complex traits remains undiscovered. PMID:27061411

  1. Epidemiology and genetics of common mental disorders in the general population: the PEGASUS-Murcia project

    PubMed Central

    Navarro-Mateu, Fernando; Tormo, MJ; Vilagut, G; Alonso, J; Ruíz-Merino, G; Escámez, T; Salmerón, D; Júdez, J; Martínez, S; Navarro, C

    2013-01-01

    environmental interactions in the aetiology of common mental disorders in representative samples of the general population. A collaborative multidisciplinary research approach offers the potential to advance our knowledge of the underlying complex interactions and this opens the field for further innovative study designs in psychiatric epidemiology. PMID:24302509

  2. Epidemiology and genetics of FTD: a door-to-door survey in Southern Italy

    PubMed Central

    Colao, Rosanna; Puccio, Gianfranco; Curcio, Sabrina AM; Mirabelli, Maria; Maletta, Raffaele; Anfossi, Maria; Gallo, Maura; Geracitano, Silvana; Conidi, Maria Elena; Di Lorenzo, Raffale; Clodomiro, Alessandra; Cupidi, Chiara; Marzano, Sandra; Comito, Francesco; Valenti, Vincenzo; Zirilli, Maria Angela; Ghani, Mahdi; Xi, Zhengrui; Sato, Christine; Moreno, Danielle; Borelli, Annelisa; Leone, Rosa Anna; St George-Hyslop, Peter; Rogaeva, Ekaterina; Bruni, Amalia C.

    2016-01-01

    Objectives To estimate FTD prevalence, identify FTD-related mutations, correlate FTD phenotype with mutations in a Southern Italian population. Methods Study population consisting of subjects ≥50 years of age residing in the Community of Biv. on January 1, 2004. Door-to-door two-phase design. Genetic and biochemical analyses were done on samples collected from 32 patients. Results Prevalence rates were 0.6 for AD, 0.4 for VD, 3.5 for FTD, 0.2 for Parkinson Dementia and 1.2 for unspecified dementia. Three GRN (one known and two novel) mutations with reduced plasma protein levels were found associated to three distinct phenotypes (behavioural, affective and delirious type). Conclusions We report an unusually high FTD prevalence in the investigated population, but a low prevalence of AD. We confirm the heterogeneity of FTD phenotype associated with different GRN mutations. PMID:22819134

  3. Cancer prevention by green tea: evidence from epidemiologic studies.

    PubMed

    Yuan, Jian-Min

    2013-12-01

    In contrast to the consistent results of an inhibitory effect of green tea extracts and tea polyphenols on the development and growth of carcinogen-induced tumors in experimental animal models, results from human studies are mixed. Both observational and intervention studies have provided evidence in support of a protective role of green tea intake in the development of oral-digestive tract cancer or an inhibitory role of oral supplementation of green tea extract on a precancerous lesion of oral cavity. Evidence in support of green tea intake against the development of liver cancer risk is limited and inconsistent. An inverse association between green tea intake and lung cancer risk has been observed among never smokers but not among smokers. Although observational studies do not support a beneficial role of tea intake against the development of prostate cancer, several phase 2 clinical trials have shown an inhibitory effect of green tea extract against the progression of prostate premalignant lesions to malignant tumors. Prospective epidemiologic studies so far have not provided evidence for a protective effect of green tea consumption on breast cancer development. Current data neither confirm nor refute a definitive cancer-preventive role of green tea intake. Large randomized intervention trials on the efficacy of green tea polyphenols or extracts are required before a recommendation for green tea consumption for cancer prevention should be made.

  4. Epigenetics and epidemiology: models of study and examples.

    PubMed

    van Veldhoven, Karin; Rahman, Shati; Vineis, Paolo

    2014-01-01

    Epidemiological studies have successfully identified several environmental causes of disease, but often these studies are limited by methodological problems (e.g. lack of sensitivity and specificity in exposure assessment; confounding). Proposed approaches to improve observational studies of environmental associations are Mendelian randomization and the meet-in-the-middle (MITM) approach. The latter uses signals from the growing field of -omics as putative intermediate biomarkers in the pathogenetic process that links exposure with disease. The first part of this approach consists in the association between exposure and disease. The next step consists in the study of the relationship between (biomarkers of) exposure and intermediate -omic biomarkers of early effect; thirdly, the relation between the disease outcome and intermediate -omic biomarkers is assessed. We propose that when an association is found in all three steps it is possible that there is a casual association. One of the associations that have been investigated extensively in the recent years but is not completely understood is that between environmental endocrine disruptors and breast cancer. Here we present an example of how the "meet-in-the-middle" approach can be used to address the role of endocrine disruptors, by reviewing the relevant literature. PMID:24114484

  5. Invited commentary: recruiting for epidemiologic studies using social media.

    PubMed

    Allsworth, Jenifer E

    2015-05-15

    Social media-based recruitment for epidemiologic studies has the potential to expand the demographic and geographic reach of investigators and identify potential participants more cost-effectively than traditional approaches. In fact, social media are particularly appealing for their ability to engage traditionally "hard-to-reach" populations, including young adults and low-income populations. Despite their great promise as a tool for epidemiologists, social media-based recruitment approaches do not currently compare favorably with gold-standard probability-based sampling approaches. Sparse data on the demographic characteristics of social media users, patterns of social media use, and appropriate sampling frames limit our ability to implement probability-based sampling strategies. In a well-conducted study, Harris et al. (Am J Epidemiol. 2015;181(10):737-746) examined the cost-effectiveness of social media-based recruitment (advertisements and promotion) in the Contraceptive Use, Pregnancy Intention, and Decisions (CUPID) Study, a cohort study of 3,799 young adult Australian women, and the approximate representativeness of the CUPID cohort. Implications for social media-based recruitment strategies for cohort assembly, data accuracy, implementation, and human subjects concerns are discussed.

  6. Enabling high-throughput genotype-phenotype associations in the Epidemiologic Architecture for Genes Linked to Environment (EAGLE) project as part of the Population Architecture using Genomics and Epidemiology (PAGE) study.

    PubMed

    Bush, William S; Boston, Jonathan; Pendergrass, Sarah A; Dumitrescu, Logan; Goodloe, Robert; Brown-Gentry, Kristin; Wilson, Sarah; McClellan, Bob; Torstenson, Eric; Basford, Melissa A; Spencer, Kylee L; Ritchie, Marylyn D; Crawford, Dana C

    2013-01-01

    Genetic association studies have rapidly become a major tool for identifying the genetic basis of common human diseases. The advent of cost-effective genotyping coupled with large collections of samples linked to clinical outcomes and quantitative traits now make it possible to systematically characterize genotype-phenotype relationships in diverse populations and extensive datasets. To capitalize on these advancements, the Epidemiologic Architecture for Genes Linked to Environment (EAGLE) project, as part of the collaborative Population Architecture using Genomics and Epidemiology (PAGE) study, accesses two collections: the National Health and Nutrition Examination Surveys (NHANES) and BioVU, Vanderbilt University's biorepository linked to de-identified electronic medical records. We describe herein the workflows for accessing and using the epidemiologic (NHANES) and clinical (BioVU) collections, where each workflow has been customized to reflect the content and data access limitations of each respective source. We also describe the process by which these data are generated, standardized, and shared for meta-analysis among the PAGE study sites. As a specific example of the use of BioVU, we describe the data mining efforts to define cases and controls for genetic association studies of common cancers in PAGE. Collectively, the efforts described here are a generalized outline for many of the successful approaches that can be used in the era of high-throughput genotype-phenotype associations for moving biomedical discovery forward to new frontiers of data generation and analysis.

  7. Low-dose radiation epidemiology studies: status and issues.

    PubMed

    Shore, Roy E

    2009-11-01

    Although the Japanese atomic bomb study and radiotherapy studies have clearly documented cancer risks from high-dose radiation exposures, radiation risk assessment groups have long recognized that protracted or low exposures to low-linear energy transfer radiations are key radiation protection concerns because these are far more common than high-exposure scenarios. Epidemiologic studies of human populations with low-dose or low dose-rate exposures are one approach to addressing those concerns. A number of large studies of radiation workers (Chernobyl clean-up workers, U.S. and Chinese radiological technologists, and the 15-country worker study) or of persons exposed to environmental radiation at moderate to low levels (residents near Techa River, Semipalatinsk, Chernobyl, or nuclear facilities) have been conducted. A variety of studies of medical radiation exposures (multiple-fluoroscopy, diagnostic (131)I, scatter radiation doses from radiotherapy, etc.) also are of interest. Key results from these studies are summarized and compared with risk estimates from the Japanese atomic bomb study. Ideally, one would like the low-dose and low dose-rate studies to guide radiation risk estimation regarding the shape of the dose-response curve, DDREF (dose and dose-rate effectiveness factor), and risk at low doses. However, the degree to which low-dose studies can do so is subject to various limitations, especially those pertaining to dosimetric uncertainties and limited statistical power. The identification of individuals who are particularly susceptible to radiation cancer induction also is of high interest in terms of occupational and medical radiation protection. Several examples of studies of radiation-related cancer susceptibility are discussed, but none thus far have clearly identified radiation-susceptible genotypes.

  8. Low-dose radiation epidemiology studies: status and issues.

    PubMed

    Shore, Roy E

    2009-11-01

    Although the Japanese atomic bomb study and radiotherapy studies have clearly documented cancer risks from high-dose radiation exposures, radiation risk assessment groups have long recognized that protracted or low exposures to low-linear energy transfer radiations are key radiation protection concerns because these are far more common than high-exposure scenarios. Epidemiologic studies of human populations with low-dose or low dose-rate exposures are one approach to addressing those concerns. A number of large studies of radiation workers (Chernobyl clean-up workers, U.S. and Chinese radiological technologists, and the 15-country worker study) or of persons exposed to environmental radiation at moderate to low levels (residents near Techa River, Semipalatinsk, Chernobyl, or nuclear facilities) have been conducted. A variety of studies of medical radiation exposures (multiple-fluoroscopy, diagnostic (131)I, scatter radiation doses from radiotherapy, etc.) also are of interest. Key results from these studies are summarized and compared with risk estimates from the Japanese atomic bomb study. Ideally, one would like the low-dose and low dose-rate studies to guide radiation risk estimation regarding the shape of the dose-response curve, DDREF (dose and dose-rate effectiveness factor), and risk at low doses. However, the degree to which low-dose studies can do so is subject to various limitations, especially those pertaining to dosimetric uncertainties and limited statistical power. The identification of individuals who are particularly susceptible to radiation cancer induction also is of high interest in terms of occupational and medical radiation protection. Several examples of studies of radiation-related cancer susceptibility are discussed, but none thus far have clearly identified radiation-susceptible genotypes. PMID:19820457

  9. Sequencing Strategies for Population and Cancer Epidemiology Studies (SeqSPACE) Webinar Series

    Cancer.gov

    The Sequencing Strategies for Population and Cancer Epidemiology Studies (SeqSPACE) Webinar Series provides an opportunity for our grantees and other interested individuals to share lessons learned and practical information regarding the application of next generation sequencing to cancer epidemiology studies.

  10. 77 FR 62518 - Proposed Collection; Comment Request: Recipient Epidemiology and Donor Evaluation Study-III (REDS...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-15

    ...: Recipient Epidemiology and Donor Evaluation Study-III (REDS-III). Type of Information Collection Request: New. Need and Use of Information Collection: The objective of the Recipient Epidemiology and Donor... medical procedures. REDS-II conducted studies of blood donor health but much more needs to be...

  11. ESTIMATING RESIDENTIAL EXPOSURE TO DRINKING WATER ARSENIC IN INNER MONGOLIA, CHINA FOR EPIDEMIOLOGIC STUDIES

    EPA Science Inventory

    ESTIMATING RESIDENTIAL EXPOSURE TO DRINKING WATER ARSENIC IN INNER MONGOLIA, CHINA FOR EPIDEMIOLOGIC STUDIES

    Richard Kwok1, Pauline Mendola1 Zhixiong Ning2, Zhiyi Liu2 and Judy Mumford1

    1) Epidemiology and Biomarkers Branch, Human Studies Division, NHEERL, US EPA, R...

  12. An epidemiological study of dengue in Delhi, India.

    PubMed

    Vikram, Kumar; Nagpal, B N; Pande, Veena; Srivastava, Aruna; Saxena, Rekha; Anvikar, Anup; Das, Aparup; Singh, Himmat; Anushrita; Gupta, Sanjeev K; Tuli, N R; Telle, Olivier; Yadav, N K; Valecha, Neena; Paul, Richard

    2016-01-01

    Delhi, the capital of India, is an important metropolitan hub for major financial and sociocultural exchanges, offering challenging threats to current public health infrastructure. In recent past, an upsurge of dengue cases in Delhi posed a significant menace to the existing dengue control policies. To reform the control strategies and take timely intervention to prevent future epidemics, an epidemiological study on the proportion of both asymptomatic and symptomatic dengue infections in selected population was conducted. The aim of the study was to investigate and assess the epidemiology of dengue infection and to estimate the proportion of asymptomatic and symptomatic dengue infections in Delhi. In this study, around 50 confirmed dengue cases, a total of 2125 individuals as household and neighbourhood contacts, with or without dengue febrile illness, were finger pricked and serologically detected as dengue positive or negative using SD Duo Bioline Rapid Diagnostic Test (SD Inc, Korea) with NS1, IgM & IgG combo test, which detected dengue virus antigen and antibodies to dengue virus in human blood. Out of 2125 individuals, 768 (36.1%) individuals showed positive dengue test with past (25.5%), primary (1.88%) or secondary (8.8%) dengue infections. Higher percentage of IgG was found in age groups 15-24 years and 25-50 years (36% each). Infants (<1 year) presented higher incidence of new infections (22% of NS1+IgM positives) as compared to adults. Further analysis revealed that out of the 226 newly infected cases (including NS1 and IgM positives), 142 (63%) were asymptomatic and 84 (37%) were symptomatic, as per WHO guidelines. Our findings also suggest that out of the total population screened, 10.6% dengue infection was either primary or secondary. On the basis of these results, it may be hypothesized that there are large number of asymptomatic dengue infections in the community as compared to reported symptomatic cases in Delhi. For the effective control of dengue

  13. Exposure assessment in industry specific retrospective occupational epidemiology studies.

    PubMed Central

    Seixas, N S; Checkoway, H

    1995-01-01

    Quantitative estimation of exposure for occupational epidemiology studies has received increasing attention in recent years and, as a result, a body of methodological literature has begun to take form. This paper reviews the generic issues in the methodology of exposure assessment, particularly methods for quantitative retrospective assessment studies. A simple framework, termed an exposure data matrix (EDM), for defining and analysing exposure data is proposed and discussed in terms of the definition of matrix dimensions and scales. Several methods for estimation, interpolation, and extrapolation, ranging from subjective ratings to quantitative statistical modelling are presented and discussed. The various approaches to exposure assessment based on the EDM concept are illustrated with studies of lung disease among coal miners and other dust and chemically induced chronic occupational diseases. The advantages of validated statistical models are emphasised. The importance of analysis and control of errors in exposure assessments, and integration of the exposure assessment and exposure-response processes, especially for emerging occupational health issues, is emphasised. PMID:7489051

  14. Molecular epidemiology and genetic diversity of human rhinovirus affecting hospitalized children in Rome.

    PubMed

    Pierangeli, Alessandra; Ciccozzi, Massimo; Chiavelli, Stefano; Concato, Carlo; Giovanetti, Marta; Cella, Eleonora; Spano, Lucia; Scagnolari, Carolina; Moretti, Corrado; Papoff, Paola; Muraca, Maurizio; Midulla, Fabio; Antonelli, Guido

    2013-08-01

    Human rhinoviruses (HRV) have been re-classified into three species (A-C), but the recently discovered HRV-C strains are not fully characterized yet. This study aimed to undertake a molecular and epidemiological characterization of HRV strains infecting children hospitalized over one year in two large research hospitals in Rome. Nasal washings from single HRV infections were retrospectively subjected to phylogenetic analysis on two genomic regions: the central part of the 5'Untranslated Region (5'UTR) and the Viral Protein (VP) 4 gene with the 5' portion of the VP2 gene (VP4/2). Forty-five different strains were identified in 73 HRV-positive children: 55 % of the cases were HRV-A, 38 % HRV-C and only 7 % HRV-B. HRV-C cases were less frequent than HRV-A during summer months and more frequent in cases presenting wheezing with respect to HRV-A. Species distribution was similar with respect to patient age, and seasonality differed during summer months with fewer HRV-C than HRV-A cases. On admission, a significantly higher number of HRV-C cases presented with wheezing with respect to HRV-A. The inter- and intra-genotype variability in VP4/2 was higher than in 5'UTR; in particular, HRV-A patient VP4/2 sequences were highly divergent (8-14 %) at the nucleotide level from those of their reference strains, but VP4 amino acid sequence was highly conserved. In HRV-C isolates, the region preceding the initiator AUG, the amino acids involved in VP4 myristoylation, the VP4-VP2 cleavage site and the cis-acting replication element were highly conserved. Differently, VP4 amino acid conservation was significantly lower in HRV-C than in HRV-A strains, especially in the transiently exposed VP4 N-terminus. This study confirmed the high number of different HRV genotypes infecting hospitalized children over one year and reveals a greater than expected variability in HRV-C VP4 protein, potentially suggestive of differences in replication.

  15. The transmission of campylobacter in piggeries; an epidemiological study.

    PubMed

    Weijtens, M J; van der Plas, J; Bijker, P G; Urlings, H A; Koster, D; van Logtestijn, J G; Huis in't Veld, J H

    1997-12-01

    The campylobacter infection of 10 sows and their piglets was monitored. These pigs were kept on two multiplier farms. Rectal faeces samples were taken from the sows shortly before littering and at different intervals after littering. Swab samples of rectal content were taken from six piglets per sow at different intervals after birth. Nine sows were shown to be infected with campylobacter before litter and all sows after litter, with an average colony count of 4.1 in log N g-1 of faeces. Half of the piglets became infected with campylobacter during the first week of life and 85%, after four weeks. Two genetic subtyping methods (ERIC-PCR and RFLP) were used to study the relationships between campylobacter isolates from sows and piglets. A large diversity of campylobacter subtypes was found. Nevertheless, piglets and their mothers often harboured campylobacter isolates with identical genetic subtyping profiles, suggesting that piglets become infected via their mothers. However, observed similarities in genetic subtyping profiles between campylobacters isolated on different farms made this difficult to prove.

  16. Cognition and Vascular Risk Factors: An Epidemiological Study

    PubMed Central

    Vicario, Augusto; Del Sueldo, Mildren; Fernández, Ruth A.; Enders, Julio; Zilberman, Judith; Cerezo, Gustavo H.

    2012-01-01

    We conducted an epidemiological approach to identify the negative impact of the vascular risk factors (such as hypertension, diabetes and hypercholesterolemia) over cognition. The interesting aspect of this study was that the survey was conducted in all age groups through a voluntary call (n = 1365; ≥18 years old, both sexes; age 49 ± 15 y, female 75.7%). Thus, we demonstrated that the use of a Minimum Cognitive Examination (MCE), a brief, simple, and easy managed neuropsychological evaluation, detected a greater number of people with cognitive decline surpassing to the Minimal Mental Statement Examination alone (14.5% of the participants showed MMSE ≤24, 34,6% showed dys-executive function, and 45,8% memory impairment. Out of the 4 studied RF, the only one that was not related to cognitive impairment was dyslipemia. Finally, we noted the importance of cognitive state early detection in all age groups, even in the youngest group. Acting in the middle of the life stages, we can prevent or delay the onset of a disease in adults, nowadays incurable: dementia. PMID:22988488

  17. Biotyping of Serratia marcescens and its use in epidemiological studies.

    PubMed Central

    Grimont, P A; Grimont, F

    1978-01-01

    A Serratia marcescens biotyping system using eight carbon sources (benzoate, DL-carnitine, m-erythritol, 3-hydroxybenzoate, 4-hydroxybenzoate, lactose, D-quinate, and trigonelline), a tetrathionate reduction test, production of prodigiosin, and horse blood hemolysis was derived from a recent numerical taxonomic study (Grimont et al., J. Gen. Microbiol. 98:39-66, 1977). A total of 98.6% of 2,210 isolates from various sources could be assigned to 1 of 19 biotypes. Distribution and spread of 1,088 S. marcescens isolates throughout 13 clinical departments of Pellegrin Hospital (Bordeaux, France) were studied from 1968 through 1975. Except for one that colonized the intestinal tract of newborns, the six pigmented biotypes were seldom isolated. Each of the 13 nonpigmented biotypes showed a particular pattern of distribution and spread. The usefulness of S. marcescens biotyping was shown by relating several isolates recovered from patients and their inanimate environment and by pointing out the possible existence of infections or colonizations by two unrelated biotypes. S. marcescens strains isolated from the natural environment (water) are usually pigmented, and their biotypes are uncommon in hospitals. Biotyping can, therefore, be of help in epidemiological and ecological surveys. PMID:353073

  18. An update of epidemiologic studies of plutonium workers.

    PubMed

    Voelz, G L; Wilkinson, G S; Acquavella, J F; Tietjen, G L; Brackbill, R N; Reyes, M; Wiggs, L D

    1983-01-01

    Retrospective and prospective epidemiologic studies are being conducted as part of a national survey of plutonium workers at four Department of Energy facilities (Los Alamos, NM; Rocky Flats, CO; Mound Laboratory, OH; and Savannah River, SC). A preliminary analysis of mortality was done for all white males who have worked at the Rocky Flats Plant during the period 1952-79. The 452 observed deaths were significantly fewer than the 831 expected for all causes. The 107 deaths due to all malignant neoplasms were also significantly fewer than the 167 expected from these diseases. Expected deaths were derived from age and calendar-specific death rates for U.S. white males. Deaths reported for benign and unspecified neoplasms numbered eight versus an expected two, a significant elevation. These tumors, all intracranial, are the subject of a case-control study to be reported later. Subdividing the cohort on the basis of plutonium exposures and external radiation exposures results in similar overall findings. The benign and unspecified neoplasms, however, were not significantly high in the plutonium-exposed group. PMID:6862925

  19. An Epidemiological Study of Neuropathic Pain Symptoms in Canadian Adults

    PubMed Central

    VanDenKerkhof, Elizabeth G.; Mann, Elizabeth G.; Torrance, Nicola; Smith, Blair H.; Johnson, Ana; Gilron, Ian

    2016-01-01

    The reported prevalence of neuropathic pain ranges from 6.9% to 10%; however the only Canadian study reported 17.9%. The objective of this study was to describe the epidemiology of neuropathic pain in Canada. A cross-sectional survey was conducted in a random sample of Canadian adults. The response rate was 21.1% (1504/7134). Likely or possible neuropathic pain was defined using a neuropathic pain-related diagnosis and a positive outcome on the Self-Report Leeds Assessment of Neuropathic Symptoms and Signs pain scale (S-LANSS) or the Douleur Neuropathique 4 (DN4) Questions. The prevalence of likely neuropathic pain was 1.9% (S-LANSS) and 3.4% (DN4) and that of possible neuropathic pain was 5.8% (S-LANSS) and 8.1% (DN4). Neuropathic pain was highest in economically disadvantaged males. There is a significant burden of neuropathic pain in Canada. The low response rate and a slightly older and less educated sample than the Canadian population may have led to an overestimate of neuropathic pain. Population prevalence varies by screening tool used, indicating more work is needed to develop reliable measures. Population level screening targeted towards high risk groups should improve the sensitivity and specificity of screening, while clinical examination of those with positive screening results will further refine the estimate of prevalence. PMID:27445636

  20. Epidemiological studies of CHD and the evolution of preventive cardiology.

    PubMed

    Wong, Nathan D

    2014-05-01

    Cardiovascular diseases (CVDs) cause nearly one-third of all deaths worldwide. Coronary heart disease (CHD) accounts for the greatest proportion of CVDs, and risk factors such as hypertension, cigarette smoking, diabetes mellitus or elevated glucose level, elevated cholesterol levels, and obesity or being overweight are the top six causes of death globally. Ecological and population-based longitudinal studies, conducted globally or within individual countries, have established the role of traditional and novel risk factors and measures of subclinical disease in the prediction of CHD. Risk assessment with short-term or long-term risk prediction algorithms can help to identify individuals who would benefit most from risk-factor interventions. Evaluation of novel risk factors and screening for subclinical atherosclerosis can also help to identify individuals at highest cardiovascular risk. Prevention of CHD focuses on identifying and managing risk factors at both the population and individual levels through primordial, primary, and secondary prevention. Epidemiological studies have provided the hypotheses for subsequent clinical trials that have documented the efficacy of risk-factor interventions, which are the basis of preventive cardiology. Future research efforts will determine the screening and intervention strategies that have the greatest effect on CHD prevention. PMID:24663092

  1. Epidemiological and Immunological Studies of Cryptococcus neoformans1

    PubMed Central

    Walter, Jinks E.; Atchison, Robert W.

    1966-01-01

    Walter, Jinks E. (University of Pittsburgh, Pittsburgh, Pa.), and Robert W. Atchison. Epidemiological and immunological studies of Cryptococcus neoformans. J. Bacteriol. 92:82–87. 1966.—The complement-fixation fluorescent-antibody test provided a means of differentiating between antibodies of Cryptococcus neoformans and Candida albicans. The test was applied to the sera of 134 pigeon fanciers for detection of antibodies to C. neoformans only. About 22% were positive as compared with 3% of a control group composed of 36 non-pigeon breeders. Positive reactions were observed only with C. neoformans types A and B cells. It was concluded that the pigeon fanciers had presumably been infected previously with C. neoformans type A or type B. Moreover, 48 of 49 isolates of C. neoformans cultured from the pigeon habitats of 72 fanciers studied were serotype A. These findings would seem to substantiate the hypothesis that pigeon habitats serve as reservoirs for human infections, and also that subclinical cryptococcosis is more prevalent than is realized. Images PMID:5328755

  2. An epidemiological study of acute herniated lumbar intervertebral discs.

    PubMed

    Kelsey, J L

    1975-08-01

    In an epidemiological study of acute herniated lumbar intervertebral discs in the New Haven, Connecticut (U.S.A.), area, it was found that this condition was most likely to be diagnosed among persons in the age group 30-39 years, and that the most important risk factors among the variable considered in this study were driving of motor vehicles at or away from work, sedentary occupations, suburban residence, and previous full-term pregnancies. Variables for which there was some suggestion of an association but for which the evidence was inconclusive were the male sex, high social class among females, chronic cough and chronic bronchitis, participation in baseball, golf and bowling, the spring and fall seasons, and possibly lack of physical activity other than at work. No increase in risk for this condition was related to race, social class in males, smoking habits, participation in sports other than baseball, golf and bowling, weight or body bulk, recent episodes of emotional stress, pregnancies which were not full-term, and jobs involving lifting, pushing, pulling, or carrying.

  3. Biotyping of Serratia marcescens and its use in epidemiological studies.

    PubMed

    Grimont, P A; Grimont, F

    1978-07-01

    A Serratia marcescens biotyping system using eight carbon sources (benzoate, DL-carnitine, m-erythritol, 3-hydroxybenzoate, 4-hydroxybenzoate, lactose, D-quinate, and trigonelline), a tetrathionate reduction test, production of prodigiosin, and horse blood hemolysis was derived from a recent numerical taxonomic study (Grimont et al., J. Gen. Microbiol. 98:39-66, 1977). A total of 98.6% of 2,210 isolates from various sources could be assigned to 1 of 19 biotypes. Distribution and spread of 1,088 S. marcescens isolates throughout 13 clinical departments of Pellegrin Hospital (Bordeaux, France) were studied from 1968 through 1975. Except for one that colonized the intestinal tract of newborns, the six pigmented biotypes were seldom isolated. Each of the 13 nonpigmented biotypes showed a particular pattern of distribution and spread. The usefulness of S. marcescens biotyping was shown by relating several isolates recovered from patients and their inanimate environment and by pointing out the possible existence of infections or colonizations by two unrelated biotypes. S. marcescens strains isolated from the natural environment (water) are usually pigmented, and their biotypes are uncommon in hospitals. Biotyping can, therefore, be of help in epidemiological and ecological surveys.

  4. Sports injuries in school-aged children. An epidemiologic study.

    PubMed

    Backx, F J; Erich, W B; Kemper, A B; Verbeek, A L

    1989-01-01

    In November 1982, epidemiologic data were collected in a unique, large scale, population-based survey on sports injuries in school-aged children living in Holland. A total of 7,468 pupils, aged 8 to 17, completed questionnaires covering a retrospective period of 6 weeks. Seven hundred ninety-one sports injuries were registered, amounting to an incidence of 10.6 sports injuries per 100 participants. In 31% of the cases, medical consultation was needed. Injuries incurred during the study period caused 36% of the children to miss one or more physical education classes and caused 6% to miss school for at least 1 day. Contusions and sprains were the most common lesions (77%). Three of four injuries involved the lower extremity, in particular the ankle. Sixty-two percent of all the injuries occurred in organized sports, 21% in physical education classes, and 17% in unsupervised sports activities. The highest injury rates were found in basketball and field hockey. In this study population, 15 and 16-year-old boys who had a high sports activity index and played team sports, particularly contact team sports, formed a high risk group.

  5. Study of the epidemiology of Pneumocystis carinii f. sp. suis in abattoir swine in Portugal.

    PubMed

    Esgalhado, Rita; Esteves, Francisco; Antunes, Francisco; Matos, Olga

    2013-01-01

    Pneumocystis has been identified in various mammalian species, including domestic, wild and zoo animals. This study's main objectives were: (1) to estimate the prevalence of the Pneumocystis carinii f. sp. suis infection in slaughtered pigs in Portugal, (2) assess the prevalence differences within distinct age groups of animals, (3) determine the possible associations between pulmonary lesions and the infection, and (4) genetically characterize the P. carinii f. sp. suis isolates recovered from infected animals using PCR with DNA sequencing. An epidemiological cross-sectional study was conducted using 215 pig lung tissue samples which demonstrated a global prevalence of 7% (14 positive samples). This value was later validated by statistical analysis as being representative of the national population prevalence. Regarding the assessment of relations between the different variables investigated during the study (age, gender, geographical region, type of farming, weight and pulmonary lesion) and the P. carinii f. sp. suis infection, no significant statistical differences were found, and apparently, no predisposing factors could be defined. Nevertheless, infection by Pneumocystis in pigs is ubiquitous and it can be detected in healthy animals. Thus, the colonization of P. carinii f. sp. suis among healthy individuals suggests that asymptomatic carriers can be an effective reservoir for susceptible animals and participate in the transmission of infection. The present data confirmed that porcine Pneumocystis is genetically distinct from Pneumocystis DNA detected in other mammalian hosts.

  6. Epidemiology and Genetic Characterization of Measles Strains in Senegal, 2004-2013

    PubMed Central

    Dia, Ndongo; Fall, Ameth; Ka, Rouguiyatou; Fall, Amary; Kiori, David E.; Goudiaby, Deborah G.; Fall, Aichatou D.; Faye, El Hadj Abdourahmane; Dosseh, Annick; Ndiaye, Kader; Diop, Ousmane M.; Niang, Mbayame Nd.

    2015-01-01

    Background In Senegal, with the variable routine vaccination coverage, the risk for illness and death from measles still exists as evidenced by the measles epidemic episode in 2009. Since 2002 a laboratory-based surveillance system of measles was established by the Ministry of Health and the Institut Pasteur de Dakar. The present study analysed the data collected over the 10 years inclusive between 2004-2013 in order to define a measles epidemiological profile in Senegal, and we carried out a phylogenetic analysis of measles virus circulating in Senegal over the period 2009-2012. Methodology and Results A total number of 4580 samples were collected from suspected cases, with the most cases between 2008 and 2010 (2219/4580; 48.4%). The majority of suspected cases are found in children from 4-6 years old (29%). 981 (21.4%) were measles laboratory-confirmed by IgM ELISA. The measles confirmation rate per year is very high during 2009-2010 periods (48.5% for each year). Regarding age groups, the highest measles IgM-positivity rate occurred among persons aged over 15 years with 39.4% (115/292) followed by 2-3 years old age group with 30.4% (323/1062) and 30% (148/494) in children under one year old group. The majority of suspected cases were collected between February and June and paradoxically confirmed cases rates increased from July (77/270; 28.6%) and reached a peak in November with 60% (93/155). Phylogenetic analysis showed that all the 29 sequences from strains that circulated in Senegal between 2009 and 2012 belong to the B3 genotype and they are clustered in B3.1 (2011-2012) and B3.3 (2009-2011) sub-genotypes according to a temporal parameter. Conclusion Improvements in the measles surveillance in Senegal are required and the introduction of oral fluid and FTA cards as an alternative to transportation of sera should be investigated to improve surveillance. The introduction of a national vaccine database including number of doses of measles-containing vaccine

  7. Comparison of Mycotic Keratitis with Nonmycotic Keratitis: An Epidemiological Study

    PubMed Central

    Khater, Mohammad M.; Shehab, Nehal S.; El-Badry, Anwar S.

    2014-01-01

    Purpose. This work aims to study the problems encountered with and the different epidemiological features of patients with fungal keratitis. Patients and Methods. All cases with keratitis attending the Outpatient Clinic of Ophthalmology Department at Tanta University Hospital during three years from the first of January 2011 to the end of December 2013 were selected and carefully examined and cases with mycotic keratitis were further examined and investigated. Results. From 66303 attendants during this period with different complaints, there were 361 cases (0.54%) with mycotic keratitis and 473 cases (0.71%) of nonmycotic origin. Mycotic keratitis is common between 40 and 60 years, more in farmers (64%), families with large number and large crowding index, rural than urban residence, and patients with outdoor water sources and insanitary sewage disposal. Positive fungal cultures were obtained in 84.5% and were negative in 15.5% of cases in spite of their typical clinical findings for diagnosis and their improvement with antifungal therapy. Conclusion. Mycotic keratitis is more frequent in farmers, rural areas, outdoor water supply, insanitary sewage disposal, and patients preceded with organic trauma. Atypical clinical findings were found in some cases and not all cases improved with specific antifungal therapy. PMID:25548657

  8. [Epidemiological study of cryptococcosis in Spain: first results].

    PubMed

    Colom, M F; Frasés, S; Ferrer, C; Martín-Mazuelos, E; Hermoso-de-Mendoza, M; Torres-Rodríguez, J M; Quindós, G

    2001-09-01

    The study constitutes an approach to the knowledge of the epidemiology of cryptococosis in Spain. For detection of cases 167 Spanish hospitals were contacted. All cases included were accompanied by the correspondent isolate of Cryptococcus neoformans, together with clinical, demographic and mycological data. Results obtained from January 1998 to end of December 1999 are analysed and presented here. Fifty-six Spanish hospitals reported 58 cases of cryptococcosis; only 43 of them were adequately documented and accompanied by the clinical isolate. The results showed a higher incidence in males (88.4%) than in females (11.6%); being most frequently affected those between 30 and 40 years old (48.8%). The 84.6% (33) corresponded to new cases and 15.4% (6) to relapses of the disease. The HIV infection was the most frequent risk factor reported (86%) and, for 29.7% (11) of them, cryptococcosis was the AIDS defining disease. For the diagnosis, CSF analysis showed the best results (India ink; culture and antigen detection). All strains collected (100%) corresponded to C. neoformans variety neoformans. Serotypes distribution was 45.5% for serotype A and 22.7% for each of serotypes D and AD.

  9. Using Bayesian Networks to Model Hierarchical Relationships in Epidemiological Studies

    PubMed Central

    2011-01-01

    OBJECTIVES To propose an alternative procedure, based on a Bayesian network (BN), for estimation and prediction, and to discuss its usefulness for taking into account the hierarchical relationships among covariates. METHODS The procedure is illustrated by modeling the risk of diarrhea infection for 2,740 children aged 0 to 59 months in Cameroon. We compare the procedure with a standard logistic regression and with a model based on multi-level logistic regression. RESULTS The standard logistic regression approach is inadequate, or at least incomplete, in that it does not attempt to account for potentially causal relationships between risk factors. The multi-level logistic regression does model the hierarchical structure, but does so in a piecewise manner; the resulting estimates and interpretations differ from those of the BN approach proposed here. An advantage of the BN approach is that it enables one to determine the probability that a risk factor (and/or the outcome) is in any specific state, given the states of the others. The currently available approaches can only predict the outcome (disease), given the states of the covariates. CONCLUSION A major advantage of BNs is that they can deal with more complex interrelationships between variables whereas competing approaches deal at best only with hierarchical ones. We propose that BN be considered as well as a worthwhile method for summarizing the data in epidemiological studies whose aim is understanding the determinants of diseases and quantifying their effects. PMID:21779534

  10. [Linburg-Comstock syndrome. Epidemiologic and anatomic study, clinical applications].

    PubMed

    Hamitouche, K; Roux, J L; Baeten, Y; Allieu, Y

    2000-05-01

    The Linburg-Comstock (LC) syndrome is distinguished by the inability to actively flex the interphalangeal (IP) joint of the thumb without simultaneously flexing the distal IP joint of the index finger. Any resistance to this 'parasitic' reaction causes pain on the palmar side of the wrist or in the distal part of the forearm; this is due to an anomalous tendinous connection between the flexor pollicus longus (FPL) and the flexor digitorum profundus (FDP). An epidemiological study was carried out on 264 individuals (a total of 528 hands were examined), and the LC syndrome was found in 98 subjects (37%); women were more frequently affected than men, and bilaterally rather than unilaterally. In addition, we dissected 26 fresh cadaver upper limbs, and in seven cases found an anomalous connection between FPL and FDP. We also examined the case of a young violinist with bilateral LC syndrome, who complained of pain in the distal part of the left forearm after prolonged musical exercises. Surgical investigation determined a complete fusion between FPL and FDP of the index with a common tendon. Treatment consisted of splitting this common tendon to form two separate tendons, thereby permitting a certain degree of independence between the thumb and index finger, and which considerably improved the violinist's musical performance. A review of the literature showed that there was a large quantity of anatomical descriptions available on these types of connection. Certain publications also provide an extremely precise report on the anthropological significance of these anomalies.

  11. Meningoencephalitis by Naegleria fowleri: epidemiological study in Anzoategui state, Venezuela.

    PubMed

    Cermeño, Julman R; Hernández, Isabel; El Yasin, Helal; Tinedo, Rubén; Sánchez, Raúl; Pérez, Gladys; Gravano, Rosalía; Ruiz, Aida

    2006-01-01

    A case of primary amoebic meningoencephalitis produced by Naegleria fowleri was diagnosed in the Independencia county of Anzoategui State, Venezuela. This case motivated the realization of the present epidemiological study with the aim of identifying free-living amoebae in this area. Representative water samples were taken and physicochemical and microbiologic analyses were carried out. Trophozoites and cysts of Naegleria spp, were detected in 44.4% (n=4). An excellent concordance was found among the observations of free-living amoebae in smears and those of monoxenic cultures in non-nourishing agar with Klebsiella pneumoniae (Kappa=1; p= 0.003). A variable load of aerobic mesophils was obtained. Moulds and yeast averages presented 3.0 CFU/ml (SD +/- 2.0) and 102.9 CFU/ml (SD +/- 32.2), respectively. One hundred per cent of the samples presented a most probable number of total and fecal coliforms of 240,000 NMP/100mL. Naegleria spp was present in waters of the Independence county of Anzoategui state, which constitutes a risk for people that use these sources.

  12. [Molecular epidemiology in the epidemiological transition].

    PubMed

    Tapia-Conyer, R

    1997-01-01

    The epidemiological transition describes the changes in the health profile of populations where infectious diseases are substituted by chronic or non-communicable diseases. Even in industrialized countries, infectious diseases emerge as important public health problems and with a very important association with several type of neoplasm. Molecular epidemiology brings in new tools for the study of the epidemiological transition by discovering infectious agents as etiology of diseases, neither of both new. Much has been advanced in the understanding of the virulence and resistance mechanism of different strains, or improving the knowledge on transmission dynamics and dissemination pathways of infectious diseases. As to the non-communicable diseases, molecular epidemiology has enhanced the identification of endogenous risk factors link to alterations, molecular changes in genetic material, that will allow a more detail definition of risk and the identification of individual and groups at risk of several diseases. The potential impact of molecular epidemiology in other areas as environmental, lifestyles and nutritional areas are illustrated with several examples. PMID:9504120

  13. Summary of epidemiologic studies of lung cancer and radon in Swedish homes

    SciTech Connect

    Swedjemark, G.A.; Desai, G.

    1992-12-31

    Several epidemiologic studies of lung cancer and radon exposure in Swedish homes have been published, and an extensive study is currently being conducted over the whole country. Described is a short summary of the Swedish studies.

  14. Problem gambling and homelessness: results from an epidemiologic study.

    PubMed

    Nower, Lia; Eyrich-Garg, Karin M; Pollio, David E; North, Carol S

    2015-06-01

    The purpose of this study was to investigate the prevalence of gambling disorder and comorbid psychiatric disorders in a homeless population and identify features related to potential subtypes. At baseline, participants were administered a structured interview including socio-demographic sections of the National Comorbidity Study (NCS) interview; seven diagnostic sections of the Diagnostic Interview Schedule (DIS); the alcohol and drug abuse sections of the Composite International Diagnostic Interview-Substance Abuse Module (CIDI-SAM); and the Homeless Supplement to the DIS. At nine months post-baseline assessment, participants were administered additional NCS family history questions and the South Oaks Gambling Screen (SOGS). Participants were an epidemiologic sample of 275 predominately African-American homeless individuals, grouped as lifetime non-gamblers (n = 60), recreational gamblers (n = 152), and problem gamblers (n = 63), recruited on the street and through homeless shelters. Results indicate that lifetime rates of sub-clinical problem (46.2%) and disordered (12.0%) gambling were significantly higher than in the general population. Problem gamblers were more likely than non-problem gamblers to meet diagnostic criteria for antisocial personality disorder, post-traumatic stress disorder, bipolar disorder, and any psychiatric disorder, and more likely than non-gamblers to use illicit drugs or meet criteria for abuse/dependence for nicotine, alcohol, or any substance. This study provides evidence that problem gambling is a significant public health issue among the African-American homeless population. Homeless services should include assessment for problem gambling along with psychiatric disorders and referrals to resources and treatment programs. Future studies should explore the relationship of the onset and course of problem gambling and other psychiatric disorders with homelessness as well as racial differences in gambling patterns and problem severity

  15. Problem gambling and homelessness: results from an epidemiologic study.

    PubMed

    Nower, Lia; Eyrich-Garg, Karin M; Pollio, David E; North, Carol S

    2015-06-01

    The purpose of this study was to investigate the prevalence of gambling disorder and comorbid psychiatric disorders in a homeless population and identify features related to potential subtypes. At baseline, participants were administered a structured interview including socio-demographic sections of the National Comorbidity Study (NCS) interview; seven diagnostic sections of the Diagnostic Interview Schedule (DIS); the alcohol and drug abuse sections of the Composite International Diagnostic Interview-Substance Abuse Module (CIDI-SAM); and the Homeless Supplement to the DIS. At nine months post-baseline assessment, participants were administered additional NCS family history questions and the South Oaks Gambling Screen (SOGS). Participants were an epidemiologic sample of 275 predominately African-American homeless individuals, grouped as lifetime non-gamblers (n = 60), recreational gamblers (n = 152), and problem gamblers (n = 63), recruited on the street and through homeless shelters. Results indicate that lifetime rates of sub-clinical problem (46.2%) and disordered (12.0%) gambling were significantly higher than in the general population. Problem gamblers were more likely than non-problem gamblers to meet diagnostic criteria for antisocial personality disorder, post-traumatic stress disorder, bipolar disorder, and any psychiatric disorder, and more likely than non-gamblers to use illicit drugs or meet criteria for abuse/dependence for nicotine, alcohol, or any substance. This study provides evidence that problem gambling is a significant public health issue among the African-American homeless population. Homeless services should include assessment for problem gambling along with psychiatric disorders and referrals to resources and treatment programs. Future studies should explore the relationship of the onset and course of problem gambling and other psychiatric disorders with homelessness as well as racial differences in gambling patterns and problem severity

  16. The genetic epidemiology of nonalcoholic fatty liver disease: toward a personalized medicine.

    PubMed

    Sookoian, Silvia; Pirola, Carlos J

    2012-08-01

    The understanding of the genetic bases of complex diseases such as nonalcoholic fatty liver disease opens new opportunities and challenges. This article explores new tools designed toward moving genomic data into clinical medicine, providing putative answers to more practical questions.

  17. Descriptive Epidemiology of Somatising Tendency: Findings from the CUPID Study

    PubMed Central

    Vargas-Prada, Sergio; Coggon, David; Ntani, Georgia; Walker-Bone, Karen; Palmer, Keith T.; Felli, Vanda E.; Harari, Raul; Barrero, Lope H.; Felknor, Sarah A.; Gimeno, David; Cattrell, Anna; Bonzini, Matteo; Solidaki, Eleni; Merisalu, Eda; Habib, Rima R.; Sadeghian, Farideh; Kadir, M. Masood; Warnakulasuriya, Sudath S. P.; Matsudaira, Ko; Nyantumbu, Busisiwe; Sim, Malcolm R.; Harcombe, Helen; Cox, Ken; Sarquis, Leila M. M.; Marziale, Maria H.; Harari, Florencia; Freire, Rocio; Harari, Natalia; Monroy, Magda V.; Quintana, Leonardo A.; Rojas, Marianela; Harris, E. Clare; Serra, Consol; Martinez, J. Miguel; Delclos, George; Benavides, Fernando G.; Carugno, Michele; Ferrario, Marco M.; Pesatori, Angela C.; Chatzi, Leda; Bitsios, Panos; Kogevinas, Manolis; Oha, Kristel; Freimann, Tiina; Sadeghian, Ali; Peiris-John, Roshini J.; Sathiakumar, Nalini; Wickremasinghe, A. Rajitha; Yoshimura, Noriko; Kelsall, Helen L.; Hoe, Victor C. W.; Urquhart, Donna M.; Derrett, Sarah; McBride, David; Herbison, Peter; Gray, Andrew; Vega, Eduardo J. Salazar

    2016-01-01

    Somatising tendency, defined as a predisposition to worry about common somatic symptoms, is importantly associated with various aspects of health and health-related behaviour, including musculoskeletal pain and associated disability. To explore its epidemiological characteristics, and how it can be specified most efficiently, we analysed data from an international longitudinal study. A baseline questionnaire, which included questions from the Brief Symptom Inventory about seven common symptoms, was completed by 12,072 participants aged 20–59 from 46 occupational groups in 18 countries (response rate 70%). The seven symptoms were all mutually associated (odds ratios for pairwise associations 3.4 to 9.3), and each contributed to a measure of somatising tendency that exhibited an exposure-response relationship both with multi-site pain (prevalence rate ratios up to six), and also with sickness absence for non-musculoskeletal reasons. In most participants, the level of somatising tendency was little changed when reassessed after a mean interval of 14 months (75% having a change of 0 or 1 in their symptom count), although the specific symptoms reported at follow-up often differed from those at baseline. Somatising tendency was more common in women than men, especially at older ages, and varied markedly across the 46 occupational groups studied, with higher rates in South and Central America. It was weakly associated with smoking, but not with level of education. Our study supports the use of questions from the Brief Symptom Inventory as a method for measuring somatising tendency, and suggests that in adults of working age, it is a fairly stable trait. PMID:27128094

  18. Descriptive Epidemiology of Somatising Tendency: Findings from the CUPID Study.

    PubMed

    Vargas-Prada, Sergio; Coggon, David; Ntani, Georgia; Walker-Bone, Karen; Palmer, Keith T; Felli, Vanda E; Harari, Raul; Barrero, Lope H; Felknor, Sarah A; Gimeno, David; Cattrell, Anna; Bonzini, Matteo; Solidaki, Eleni; Merisalu, Eda; Habib, Rima R; Sadeghian, Farideh; Kadir, M Masood; Warnakulasuriya, Sudath S P; Matsudaira, Ko; Nyantumbu, Busisiwe; Sim, Malcolm R; Harcombe, Helen; Cox, Ken; Sarquis, Leila M M; Marziale, Maria H; Harari, Florencia; Freire, Rocio; Harari, Natalia; Monroy, Magda V; Quintana, Leonardo A; Rojas, Marianela; Harris, E Clare; Serra, Consol; Martinez, J Miguel; Delclos, George; Benavides, Fernando G; Carugno, Michele; Ferrario, Marco M; Pesatori, Angela C; Chatzi, Leda; Bitsios, Panos; Kogevinas, Manolis; Oha, Kristel; Freimann, Tiina; Sadeghian, Ali; Peiris-John, Roshini J; Sathiakumar, Nalini; Wickremasinghe, A Rajitha; Yoshimura, Noriko; Kelsall, Helen L; Hoe, Victor C W; Urquhart, Donna M; Derrett, Sarah; McBride, David; Herbison, Peter; Gray, Andrew; Vega, Eduardo J Salazar

    2016-01-01

    Somatising tendency, defined as a predisposition to worry about common somatic symptoms, is importantly associated with various aspects of health and health-related behaviour, including musculoskeletal pain and associated disability. To explore its epidemiological characteristics, and how it can be specified most efficiently, we analysed data from an international longitudinal study. A baseline questionnaire, which included questions from the Brief Symptom Inventory about seven common symptoms, was completed by 12,072 participants aged 20-59 from 46 occupational groups in 18 countries (response rate 70%). The seven symptoms were all mutually associated (odds ratios for pairwise associations 3.4 to 9.3), and each contributed to a measure of somatising tendency that exhibited an exposure-response relationship both with multi-site pain (prevalence rate ratios up to six), and also with sickness absence for non-musculoskeletal reasons. In most participants, the level of somatising tendency was little changed when reassessed after a mean interval of 14 months (75% having a change of 0 or 1 in their symptom count), although the specific symptoms reported at follow-up often differed from those at baseline. Somatising tendency was more common in women than men, especially at older ages, and varied markedly across the 46 occupational groups studied, with higher rates in South and Central America. It was weakly associated with smoking, but not with level of education. Our study supports the use of questions from the Brief Symptom Inventory as a method for measuring somatising tendency, and suggests that in adults of working age, it is a fairly stable trait. PMID:27128094

  19. Descriptive Epidemiology of Somatising Tendency: Findings from the CUPID Study.

    PubMed

    Vargas-Prada, Sergio; Coggon, David; Ntani, Georgia; Walker-Bone, Karen; Palmer, Keith T; Felli, Vanda E; Harari, Raul; Barrero, Lope H; Felknor, Sarah A; Gimeno, David; Cattrell, Anna; Bonzini, Matteo; Solidaki, Eleni; Merisalu, Eda; Habib, Rima R; Sadeghian, Farideh; Kadir, M Masood; Warnakulasuriya, Sudath S P; Matsudaira, Ko; Nyantumbu, Busisiwe; Sim, Malcolm R; Harcombe, Helen; Cox, Ken; Sarquis, Leila M M; Marziale, Maria H; Harari, Florencia; Freire, Rocio; Harari, Natalia; Monroy, Magda V; Quintana, Leonardo A; Rojas, Marianela; Harris, E Clare; Serra, Consol; Martinez, J Miguel; Delclos, George; Benavides, Fernando G; Carugno, Michele; Ferrario, Marco M; Pesatori, Angela C; Chatzi, Leda; Bitsios, Panos; Kogevinas, Manolis; Oha, Kristel; Freimann, Tiina; Sadeghian, Ali; Peiris-John, Roshini J; Sathiakumar, Nalini; Wickremasinghe, A Rajitha; Yoshimura, Noriko; Kelsall, Helen L; Hoe, Victor C W; Urquhart, Donna M; Derrett, Sarah; McBride, David; Herbison, Peter; Gray, Andrew; Vega, Eduardo J Salazar

    2016-01-01

    Somatising tendency, defined as a predisposition to worry about common somatic symptoms, is importantly associated with various aspects of health and health-related behaviour, including musculoskeletal pain and associated disability. To explore its epidemiological characteristics, and how it can be specified most efficiently, we analysed data from an international longitudinal study. A baseline questionnaire, which included questions from the Brief Symptom Inventory about seven common symptoms, was completed by 12,072 participants aged 20-59 from 46 occupational groups in 18 countries (response rate 70%). The seven symptoms were all mutually associated (odds ratios for pairwise associations 3.4 to 9.3), and each contributed to a measure of somatising tendency that exhibited an exposure-response relationship both with multi-site pain (prevalence rate ratios up to six), and also with sickness absence for non-musculoskeletal reasons. In most participants, the level of somatising tendency was little changed when reassessed after a mean interval of 14 months (75% having a change of 0 or 1 in their symptom count), although the specific symptoms reported at follow-up often differed from those at baseline. Somatising tendency was more common in women than men, especially at older ages, and varied markedly across the 46 occupational groups studied, with higher rates in South and Central America. It was weakly associated with smoking, but not with level of education. Our study supports the use of questions from the Brief Symptom Inventory as a method for measuring somatising tendency, and suggests that in adults of working age, it is a fairly stable trait.

  20. Epidemiological studies on radiation carcinogenesis in human populations following acute exposure: nuclear explosions and medical radiation

    SciTech Connect

    Fabrikant, J.I.

    1982-08-01

    The present review provides an understanding of our current knowledge of the carcinogenic effect of low-dose radiation in man, and surveys the epidemiological studies of human populations exposed to nuclear explosions and medical radiation. Discussion centers on the contributions of quantitative epidemiology to present knowledge, the reliability of the dose-incidence data, and those relevant epidemiological studies that provide the most useful information for risk estimation of cancer-induction in man. Reference is made to dose-incidence relationships from laboratory animal experiments where they may obtain for problems and difficulties in extrapolation from data obtained at high doses to low doses, and from animal data to the human situation. The paper describes the methods of application of such epidemiological data for estimation of excess risk of radiation-induced cancer in exposed human populations, and discusses the strengths and limitations of epidemiology in guiding radiation protection philosophy and public health policy.

  1. The Genetics of Obsessive-Compulsive Disorder and Tourette Syndrome: An Epidemiological and Pathway-Based Approach for Gene Discovery

    ERIC Educational Resources Information Center

    Grados, Marco A.

    2010-01-01

    Objective: To provide a contemporary perspective on genetic discovery methods applied to obsessive-compulsive disorder (OCD) and Tourette syndrome (TS). Method: A review of research trends in genetics research in OCD and TS is conducted, with emphasis on novel approaches. Results: Genome-wide association studies (GWAS) are now in progress in OCD…

  2. The Biomonitoring, Environmental Epidemiology, and Short-Lived Chemicals (BEES-C) Instrument for Assessing Study Quality

    EPA Science Inventory

    Environmental epidemiology studies can be an effective means to assess impacts on human health from exposure to environmental stressors. Exposure scenarios are often extremely complex and proper assessment is critical for interpreting epidemiological study results. Biomarkers are...

  3. Development of a Multiple-Locus Variable-Number Tandem-Repeat Typing Scheme for Genetic Fingerprinting of Burkholderia cenocepacia and Application to Nationwide Epidemiological Analysis

    PubMed Central

    Thouverez, Michelle; Barthe, Antoine; Bossuet-Greif, Nadège; Tisseyre, Lenka; Plésiat, Patrick; Vergnaud, Gilles; Chabanon, Gérard; Pourcel, Christine

    2014-01-01

    Organisms of the Burkholderia cepacia complex are especially important pathogens in cystic fibrosis (CF), with a propensity for patient-to-patient spread and long-term respiratory colonization. B. cenocepacia and Burkholderia multivorans account for the majority of infections in CF, and major epidemic clones have been recognized throughout the world. The aim of the present study was to develop and evaluate a multilocus variable-number tandem-repeat (VNTR) analysis (MLVA) scheme for B. cenocepacia. Potential VNTR loci were identified upon analysis of the annotated genome sequences of B. cenocepacia strains AU1054, J2315, and MCO-3, and 10 of them were selected on the basis of polymorphisms and size. A collection of 100 B. cenocepacia strains, including epidemiologically related and unrelated strains, as well as representatives of the major epidemic lineages, was used to evaluate typeability, epidemiological concordance, and the discriminatory power of MLVA-10 compared with those of pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). Longitudinal stability was assessed by testing 39 successive isolates from 14 patients. Typeability ranged from 0.91 to 1, except for that of one marker, which was not amplified in 53% of the B. cenocepacia IIIA strains. The MLVA types were shown to be stable in chronically colonized patients and within outbreak-related strains, with excellent epidemiological concordance. Epidemic and/or globally distributed lineages (epidemic Edinburgh-Toronto electrophoretic type 12 [ET-12], sequence type 32 [ST-32], ST-122, ST-234, and ST-241) were successfully identified. Conversely, the discriminatory power of MLVA was lower than that of PFGE or MLST, although PFGE variations within the epidemic lineages sometimes masked their genetic relatedness. In conclusion, MLVA represents a promising cost-effective first-line tool in B. cenocepacia surveillance. PMID:25411181

  4. Development of a multiple-locus variable-number tandem-repeat typing scheme for genetic fingerprinting of Burkholderia cenocepacia and application to nationwide epidemiological analysis.

    PubMed

    Segonds, Christine; Thouverez, Michelle; Barthe, Antoine; Bossuet-Greif, Nadège; Tisseyre, Lenka; Plésiat, Patrick; Vergnaud, Gilles; Chabanon, Gérard; Pourcel, Christine

    2015-02-01

    Organisms of the Burkholderia cepacia complex are especially important pathogens in cystic fibrosis (CF), with a propensity for patient-to-patient spread and long-term respiratory colonization. B. cenocepacia and Burkholderia multivorans account for the majority of infections in CF, and major epidemic clones have been recognized throughout the world. The aim of the present study was to develop and evaluate a multilocus variable-number tandem-repeat (VNTR) analysis (MLVA) scheme for B. cenocepacia. Potential VNTR loci were identified upon analysis of the annotated genome sequences of B. cenocepacia strains AU1054, J2315, and MCO-3, and 10 of them were selected on the basis of polymorphisms and size. A collection of 100 B. cenocepacia strains, including epidemiologically related and unrelated strains, as well as representatives of the major epidemic lineages, was used to evaluate typeability, epidemiological concordance, and the discriminatory power of MLVA-10 compared with those of pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). Longitudinal stability was assessed by testing 39 successive isolates from 14 patients. Typeability ranged from 0.91 to 1, except for that of one marker, which was not amplified in 53% of the B. cenocepacia IIIA strains. The MLVA types were shown to be stable in chronically colonized patients and within outbreak-related strains, with excellent epidemiological concordance. Epidemic and/or globally distributed lineages (epidemic Edinburgh-Toronto electrophoretic type 12 [ET-12], sequence type 32 [ST-32], ST-122, ST-234, and ST-241) were successfully identified. Conversely, the discriminatory power of MLVA was lower than that of PFGE or MLST, although PFGE variations within the epidemic lineages sometimes masked their genetic relatedness. In conclusion, MLVA represents a promising cost-effective first-line tool in B. cenocepacia surveillance.

  5. Epidemiological studies on Schistosoma bovis in Iringa Region, Tanzania.

    PubMed

    Kassuku, A; Christensen, N O; Monrad, J; Nansen, P; Knudsen, J

    1986-06-01

    Various aspects of the epidemiology of Schistosoma bovis were studied over a one-year period in Iringa Region, Tanzania. An abattoir survey revealed an overall prevalence rate of 30.8% in cattle and 3.8% in goats in the area, and field studies on two dairy farms both providing good opportunities for schistosome transmission provided information concerning the transmission ecology of S. bovis in relation to different types of grazing and water supply. The traditional management system on one farm with a large number of cattle utilizing a limited water resource highly suitable for sustaining populations of the snail host Bulinus africanus resulted in intensive transmission as evidenced by uptake of massive infections in calves and development of resistance to S. bovis challenge in dairy cows. On another farm, appropriate management comprising watering of cattle at a B. africanus-free pond provided the background for less intensive transmission in that transmission risk was confined to occasional contact with water contact sites of secondary importance. Besides, the transmission pattern as regards intensity and seasonality was affected markedly by the geographical and seasonal distribution of the host snail B. africanus. Thus, transmission in canals and temporary ponds was limited mainly to the dry season and the end of the rainy season, respectively, while transmission in permanent ponds occurred intermittently throughout at least most of the year. It is concluded that prevention of severe loss of productivity in domestic ruminants due to schistosome infections should be possible using strategic management procedures provided that essential information is available concerning the pattern of transmission in the particular area. PMID:2874712

  6. FEASIBILITY OF MATCHING STUDY PARTICIPANT RESIDENCE WITH SPECIFIC WATER UTILITY TRIHALOMETHANE (THM) DATA IN EPIDEMIOLOGIC STUDIES

    EPA Science Inventory

    Many epidemiologic studies concerning by-products of water disinfection use utility monitoring data to estimate exposure. Use of such data requires linkage of residence location to a specific water utility and associated monitoring data during a given exposure period. The inabil...

  7. Development and perspective of current Brazilian studies on the epidemiology of childhood leukemia.

    PubMed

    Pombo de Oliveira, Maria S; Koifman, Sergio; Vasconcelos, Gisele M; Emerenciano, Mariana; de Oliveira Novaes, Cristiane

    2009-01-01

    In this concise report, we describe the history and evolution of childhood acute leukemia studies in Brazil, and the application if key biomarkers for clinical trials and epidemiological studies over the past 8 years. Highlights of each ongoing study are summarized. A Brazilian network integrating hospitals and scientific institutions from all country regions has been established. This organization is made possible through informatics and computer networking, and the standardization of pathological reviews including immunophenotyping and molecular characterization of childhood leukemias. The unique characteristics of the Brazilian population combined with a large clinical and epidemiologic framework for patient ascertainment has enabled large-scale epidemiological studies on childhood leukemia in Brazil. PMID:19064327

  8. Use of Quantitative Microbial Risk Assessment to Improve Interpretation of a Recreational Water Epidemiological Study

    EPA Science Inventory

    We conducted a supplemental water quality monitoring study and quantitative microbial risk assessment (QMRA) to complement the United States Environmental Protection Agency’s (U.S. EPA) National Epidemiological and Environmental Assessment of Recreational Water study at Boq...

  9. EPIDEMIOLOGIC CONCEPTS FOR INTERPRETING FINDINGS IN STUDIES OF DRINKING WATER EXPOSURES

    EPA Science Inventory

    To the inexperienced, environmental epidemiology may appear to be an uncomplicated, straightforward approach to studying exposure-disease associations in human populations. The studies can provide useful information about the risks of environmental exposures that human populatio...

  10. [The use of genetic engineering in veterinary medicine with examples from epidemiology, diagnosis and drug production].

    PubMed

    Mayr, A; Hübert, P

    1990-04-01

    The results of genetic engineering have reached practical veterinary medicine already. Nevertheless there is a great lack of knowledge among those veterinarians who usually do not work with these methods. Therefore we want to give an introduction into the advantages and dangers of this technology concerning veterinary medicine. Some important analytical methods are explained. Related viruses such as WEE and EEE or canine parvovirus, feline parvovirus and mink enteritis virus, or the related coronaviruses FIPV and TGEV serve as examples for the possibilities in molecular diagnosis and epidemic monitoring. The history of the gl- mutants of PRV, now prescribed as vaccine strains in the FRG, is an example of the development of genetic engineered vaccines. A new generation of vaccines based on recombinant vaccinia viruses is imminent. Thus we have to be aware of the high risks and responsibility of everybody who is involved in these new systems, especially the scientist who produces genetically altered organisms. PMID:2112273

  11. Acute giardiasis: an improved clinical case definition for epidemiologic studies.

    PubMed

    Hopkins, R S; Juranek, D D

    1991-02-15

    In June 1983, an outbreak of waterborne giardiasis occurred in a group of 93 university students and faculty participating in a geology field course in Colorado. All cases occurred in one subgroup of persons who were heavily exposed to untreated stream water on a field trip, and the risk of illness was strongly related to the amount of untreated stream water consumed. The median incubation period from a brief exposure to the first symptom was 7 days. The authors compared symptoms and stool sample results among 31 Giardia-positive persons in the exposed group and 36 Giardia-negative participants in an unexposed group to assess several case definitions for acute giardiasis. Diarrhea, abdominal cramps, flatulence, foul-smelling stools, nausea, excessive tiredness, bloating, anorexia, and chills were each significantly more common in the first group than in the second. A giardiasis case definition of 5 days or more of diarrhea--the definition used in many epidemiologic studies of giardiasis--had a specificity of 100 percent but a sensitivity of only 32.2 percent compared with a definition based on results of stool examinations. When a case was defined as an illness lasting 7 days or more, with a combination of two or more of six symptoms (diarrhea, flatulence, foul-smelling stools, nausea, abdominal cramps, and excessive tiredness), sensitivity rose to 73 percent, with a specificity of 88 percent. Such a case definition may be an improvement over that of 5 days of diarrhea, especially in outbreaks where there is good laboratory documentation that Giardia is the etiologic agent. The definition should be validated in other outbreaks and in situations where giardiasis must be distinguished from gastrointestinal disease caused by other agents. PMID:1994703

  12. An Epidemiological Study on Ankylosing Spondylitis in Southern Albania

    PubMed Central

    Koko, Vjollca; Ndrepepa, Ana; Skënderaj, Skënder; Ploumis, Avraam; Backa, Teuta; Tafaj, Argjend

    2014-01-01

    Objectives: To evaluate the incidence and prevalence of ankylosing spondylitis (AS) in southern Albania and to assess the association of various demographic risk factors with the severity of disease. Material and methods: This is an observational study with cross-sectional analyses, conducted in the region of Gjirokaster, between 1995 until 2011. The diagnosis of AS was based on the modified New York criteria. Data on population are obtained from the reports of the National Institute of Statistics. Results: Between 1995 and 2011, there were 54 patients diagnosed with AS. Of them, 48 subjects were males (88.9%) and 6 subjects females (11.1%). The AS prevalence in adult population (≥14 years of age), in December 2010, was 0.061%. The 5-year incidence (2006–2010) in adult population was 0.006 %. The mean age at the onset of disease was 29.7±8.4 years. The mean age in 2011 (n=50 subjects) was 51.6±12.7 years. The duration of the disease was 22.7±11.2 years. More than two thirds of the patients (70.3%) were in the advanced radiological stages of the disease. A younger age at the onset of the disease, longer delay in diagnosis, lower educational level and smoking were significant independent factors associated with the advanced forms of the disease. Conclusion: In southern Albania, the AS prevalence in 2010 was 0.061% and the 5-year incidence (2006-2010) was 6 new cases per 105 adults. The incidence and prevalence of AS in Southern Albania are close to the respective regional epidemiological data. PMID:24757397

  13. Epidemiological study of Toxoplasma gondii infection in ovine breeding.

    PubMed

    Zedda, M T; Rolesu, S; Pau, S; Rosati, I; Ledda, S; Satta, G; Patta, C; Masala, G

    2010-12-01

    An outbreak of toxoplasmosis occurring in a typical farm of 524 ovines was monitored for 1 year after the occurrence of 31 abortions. Abortion events involved 7.2% of 430 pregnant sheep. Presence of antibodies to Toxoplasma gondii in sheep sera was investigated by the indirect fluorescence antibody test (IFAT). A total of 422 ewes were bled four times during the year, and an epidemiological analysis was performed on all serology data collected in this subgroup. The prevalence of IgG positives ranged from 31.52% (133/422) at the first sampling to 62.56% (264/422) at the fourth sampling. Incidence of IgG antibodies was 38.75% at the second sampling, 14.92% at the third and 29.28% at the fourth sampling. At the beginning of the study, prevalence was 70.7% in primiparous sheep and 20.9% in sheep older than 5 years; at the third sampling, prevalence was stable at 70% in pluriparous sheep. The mean prevalence of IgM antibodies was 14.87%. A total of 147 out of all 524 ovines of the flock tested positive for IgM in more than one sampling. After an initial positivity, 60 sheep tested negative for IgG at the following serological controls (4 between the first and the second sampling, 30 between the second and the third and 28 between the third and the fourth sampling). One stray cat was positive for IgG, with a titre of 1 : 320. Moreover, one of the farmers was also positive, with a titre of 1 : 160 for IgG. A positive PCR result for T. gondii DNA was also observed in aliquots of grain and pellets taken from feed stocks amassed inside the sheds without protection, suggesting that an adequate management of the farm might be useful, if not essential, for controlling T. gondii outbreaks in ovine flocks.

  14. Measles in suburban Khartoum: an epidemiological and clinical study.

    PubMed

    Ibrahim, S A; Mustafa, O M; Mukhtar, M M; Saleh, E A; El Mubarak, H S; Abdallah, A; El-Hassan, A M; Osterhaus, A D M E; Groen, J; De Swart, R L; Zijlstra, E E

    2002-05-01

    Clinical and epidemiological data were collected from 187 clinically diagnosed measles patients in Haj Yousif area, suburban Khartoum. Laboratory tests confirmed the diagnosis in 141 (75%) of the cases, but demonstrated that in 46 (25%) patients the clinical symptoms were not caused by an acute measles virus (MV) infection. According to their vaccination card, 59% of the laboratory-confirmed measles cases had been vaccinated for measles. Compared with non-measles rash disease cases, confirmed measles cases more often had severe illness (P < 0.0001), were dehydrated (P=0.01) at presentation and less likely to recover without complications [OR 0.19 (95% CI 0.09, 0.39)]. There was no difference in death rate (P=0.20). Underweight [weight-for-age Z score (WAZ) studied were predictive of outcome. Mortality was higher in the severe measles group [OR 8.8 (95% CI 1.7, 85.2)]. In 11 of 141 confirmed measles cases serological evidence of a recent infection with another virus was found, most commonly varicella zoster virus and dengue virus; spotted fever and rubella were among the most frequent diagnoses in 17 of 47 cases of the non-measles cases.

  15. Epidemiology of major incidents: an EMS study from Pakistan

    PubMed Central

    2011-01-01

    Background A major incident is defined as an event that owing to the number of casualties has the potential to overwhelm the available resources. This paper attempts to describe the incidence and epidemiology of major incidents dealt with by a government-run emergency medical service (EMS) in the Punjab province of Pakistan, a developing country in South Asia. A major incident in this EMS is defined as any incident that produces three or more patients, or any incident in which extraordinary resources are needed. Methods All the calls received by an EMS Rescue 1122 were studied over a 6-month period. Calls that were defined as major incidents were identified, and further details were sought from the districts regarding these incidents. Questions specifically asked were the type of incident, time of the incident, response time for the incident, the resources needed, and the number of dead and injured casualties. Retrospective data were collected from the submitted written reports. Results Road traffic crashes (RTCs) emerged as the leading cause of a major incident in the province of Punjab and also led to the greatest number of casualties, followed by fire incidents. The total number of casualties was 3,380, out of which 73.7% were RTC victims. There was a high rate of death on the scene (10.4%). Certain other causes of major incidents also emerged, including violence, gas explosions and drowning. Conclusion Road traffic crashes are the most common cause of a major incident in developing countries such as Pakistan. Injury prevention initiatives need to focus on RTCs. PMID:21798011

  16. Epidemiology and genetic characteristics of pigeon circovirus (PiCV) in eastern China.

    PubMed

    Zhang, Zhicheng; Dai, Wei; Wang, Shaohui; Dai, Dingzhen

    2015-01-01

    Pigeon circovirus (PiCV) is one of four viruses in the family Circoviridae that affect young pigeons around the world. We collected 158 serum or tissue samples from six poultry farms in eastern China to investigate the prevalence and genetic characteristics of PiCV in Chinese pigeons. We tested for PiCV using a PCR assay and found that PiCV was present in 80.7 % (88/109) of diseased pigeons and 63.3 % (31/49) of healthy pigeons; overall, 75.3 % (119/158) of samples were PiCV positive. One PiCV-positive sample from each poultry farm was randomly chosen for amplification of the complete PiCV genome by inverse primer PCR (IP-PCR). The six genomic PiCV strains were designated as AHBZ (KJ704801), HBLF-E2 (KJ704802), JSJN (KJ704803), NJPK-21 (KJ704804), SDDZ (KJ704805) and SHWH-AB4 (KJ704806). We compared these new PiCV genomes to six publicly available PiCV genomes and found that the Rep and Cap genes had sequence identity ranging from 93.8 % to 100 % and 79.1 % to 100 %, respectively. In a phylogenetic analysis, PiCV and eight other members of the genus Circovirus were sister to chicken anemia virus (CAV), the only member of genus Gyrovirus. The results of this study provide evidence that PiCV is present in Chinese pigeons at a high rate and that PiCV is a viral lineage that is distinct from CAV.

  17. Risk of Cancer in relation to Natural Radiation, including Radon: Evidence from Epidemiological Studies

    NASA Astrophysics Data System (ADS)

    Baysson, Hélène; Tirmarche, Margot; Laurier, Dominique

    2008-08-01

    A review of recently published epidemiological studies on populations exposed to natural background ionizing radiation is proposed. The advantages and disadvantages of different types of epidemiological studies as well as the uncertainty linked to multiple exposures are discussed. As radon is the greatest source of natural radiation, particular attention is given to quantification of risk obtained through cohort studies of uranium miners and after joint analysis of case-control studies on lung cancer and residential radon.

  18. Risk of Cancer in relation to Natural Radiation, including Radon: Evidence from Epidemiological Studies

    SciTech Connect

    Baysson, Helene; Tirmarche, Margot; Laurier, Dominique

    2008-08-07

    A review of recently published epidemiological studies on populations exposed to natural background ionizing radiation is proposed. The advantages and disadvantages of different types of epidemiological studies as well as the uncertainty linked to multiple exposures are discussed. As radon is the greatest source of natural radiation, particular attention is given to quantification of risk obtained through cohort studies of uranium miners and after joint analysis of case-control studies on lung cancer and residential radon.

  19. Detection of Healthcare-Related Extended-Spectrum Beta-Lactamase-Producing Escherichia coli Transmission Events Using Combined Genetic and Phenotypic Epidemiology

    PubMed Central

    Boers, Stefan A.; Jansen, Ruud; Hays, John P.; Goessens, Wil H. F.; Vos, Margreet C.

    2016-01-01

    Background Since the year 2000 there has been a sharp increase in the prevalence of healthcare-related infections caused by extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli. However, the high community prevalence of ESBL-producing E. coli isolates means that many E. coli typing techniques may not be suitable for detecting E. coli transmission events. Therefore, we investigated if High-throughput MultiLocus Sequence Typing (HiMLST) and/or Raman spectroscopy were suitable techniques for detecting recent E. coli transmission events. Methods This study was conducted from January until December 2010 at Erasmus University Medical Center, Rotterdam, the Netherlands. Isolates were typed using HiMLST and Raman spectroscopy. A genetic cluster was defined as two or more patients carrying identical isolates. We used predefined definitions for epidemiological relatedness to assess healthcare-related transmission. Results We included 194 patients; strains of 112 patients were typed using HiMLST and strains of 194 patients were typed using Raman spectroscopy. Raman spectroscopy identified 16 clusters while HiMLST identified 10 clusters. However, no healthcare-related transmission events were detected. When combining data from both typing techniques, we identified eight clusters (n = 34 patients), as well as 78 patients with a non-cluster isolate. However, we could not detect any healthcare-related transmission in these 8 clusters. Conclusions Although clusters were genetically detected using HiMLST and Raman spectroscopy, no definite epidemiological relationships could be demonstrated which makes the possibility of healthcare-related transmission events highly unlikely. Our results suggest that typing of ESBL-producing E. coli using HiMLST and/or Raman spectroscopy is not helpful in detecting E. coli healthcare-related transmission events. PMID:27463231

  20. Characterizing the ADHD Phenotype for Genetic Studies

    ERIC Educational Resources Information Center

    Stevenson, Jim; Asherson, Phil; Hay, David; Levy, Florence; Swanson, Jim; Thapar, Anita; Willcutt, Erik

    2005-01-01

    The genetic study of ADHD has made considerable progress. Further developments in the field will be reliant in part on identifying the most appropriate phenotypes for genetic analysis. The use of both categorical and dimensional measures of symptoms related to ADHD has been productive. The use of multiple reporters is a valuable feature of the…

  1. Allergic bronchopulmonary aspergillosis in cystic fibrosis. A European epidemiological study. Epidemiologic Registry of Cystic Fibrosis.

    PubMed

    Mastella, G; Rainisio, M; Harms, H K; Hodson, M E; Koch, C; Navarro, J; Strandvik, B; McKenzie, S G

    2000-09-01

    Allergic bronchopulmonary aspergillosis (ABPA) is a disease resulting from a hypersensitivity response to Aspergillus fumigatus, although the pathogenesis of the disease is unknown and its prevalence in cystic fibrosis (CF) is still poorly defined. Data from the Epidemiologic Registry of Cystic Fibrosis (ERCF) on 12,447 CF patients gathered from 224 CF centres in nine European countries were analysed. The ERCF definition of ABPA diagnosis is a positive skin test and serum precipitins to A. fumigatus, together with serum immunoglobulin (Ig)E levels >1,000 U x mL(-1) and additional clinical or laboratory parameters. The overall prevalence of ABPA in the ERCF population was 7.8% (range: 2.1% in Sweden to 13.6% in Belgium). Prevalence was low <6 yrs of age but was almost constant approximately 10% thereafter. No sex differences were observed. ABPA affected 8.0% of patients with a deltaF508/deltaF508 genotype and 5-6% with deltaF508/G551D, deltaF508/G542X and deltaF508/N1303K genotypes. ABPA patients presented a lower forced expiratory volume in one second (FEV1) than those without ABPA at any age and the prevalence ranged from 6.6% in patients with FEV1 > or =20-12.9% in those with FEV1 <40%. ABPA was associated with higher rates of microbial colonization, pneumothorax and massive haemoptysis, and with higher IgG serum levels and poorer nutritional status. A mixed model regression analysis of lung function showed that FEVI decline during the follow-up period was not substantially different in ABPA patients compared with non-ABPA patients for any subgroups based on age or disease severity at enrollment. To conclude, allergic bronchopulmonary aspergillosis is a frequent complication in cystic fibrosis patients, particularly after the age of 6 yrs, and it is generally associated with a poorer clinical condition. However, any clear independent influence of allergic bronchopulmonary aspergillosis on the rate of lung function decline in the short term was not shown.

  2. The Exposure Dimension of Environmental Epidemiology: A Critical but Under-ExploredStudy Quality Issue in Environmental Health

    EPA Science Inventory

    Epidemiological research plays a critical role in assessing the effects of various chemical, physical, oiological, and social exposures on human health both in the general population and the workplace. However, even epidemiological studies that are specifically designed to test c...

  3. A molecular epidemiology case control study on pleural malignant mesothelioma.

    PubMed

    Bolognesi, Claudia; Martini, Fernanda; Tognon, Mauro; Filiberti, Rosa; Neri, Monica; Perrone, Emanuela; Landini, Eleonora; Canessa, Paolo A; Ivaldi, Gian Paolo; Betta, Pietro; Mutti, Luciano; Puntoni, Riccardo

    2005-07-01

    Pleural malignant mesothelioma is an uncommon neoplasm usually associated with asbestos exposure. The increasing incidence of malignant mesothelioma cases involving individuals with low levels of asbestos exposure suggests a complex carcinogenetic process with the involvement of other cofactors. Cytogenetic studies revealed the complexity of the genetic changes involved in this neoplasm reflecting the accumulation of genomic damage. One of the most used methodologies for assessing genomic damage is the cytokinesis-blocked micronucleus test applied in peripheral blood lymphocytes (PBL). This approach allows the detection of chromosomal alterations expressed in binucleated cells after nuclear division in vitro. This marker could provide a tool for assessing genetically determined constitutional differences in chromosomal instability. A biomonitoring study was carried out to evaluate the micronuclei frequency in PBLs of patients with pleural malignant mesothelioma with respect to lung cancer, healthy, and risk controls as a marker of cancer susceptibility in correlation with the presence of SV40. A significant increased micronuclei frequency was observed in patients with malignant mesothelioma in comparison with all the other groups, the mean micronuclei frequency was double in patients with malignant mesothelioma compared with healthy controls, risk controls, and patients with lung adenocarcinoma (median 11.4 binucleated cells with micronuclei/1,000 binucleated cells versus 6.2, 6.1, and 5.1, respectively). Our data indicate that human T lymphocyte samples carry DNA sequences coding for SV40 large T antigen at low prevalence, both in cancer cases and controls. Evidence of cytogenetic damage revealed as micronuclei frequency in mesothelioma cancer patients could be related to exogenous and endogenous cofactors besides asbestos exposure.

  4. Epidemiological Study of Road Traffic Accident Cases from Western Nepal

    PubMed Central

    Mishra, Badrinarayan; Sinha (Mishra), Nidhi D; Sukhla, SK; Sinha, AK

    2010-01-01

    Background: Road Traffic Accident (RTA) is one among the top five causes of morbidity and mortality in South-East Asian countries.(1) Its socioeconomic repercussions are a matter of great concern. Efficient addressing of the issue requires quality information on different causative factors. Research Question: What are different epidemiological determinants of RTA in western Nepal? Objective: To examine the factors associated with RTA. Study Design: Prospective observational. Setting: Study was performed in a tertiary healthcare delivery institute in western Nepal. Participants: 360 victims of RTA who reported to Manipal Teaching hospital in one year. Study Variables: Demographic, human, vehicular, environmental and time factors. Statistical analysis: Percentages, linear and logarithmic trend and Chi-square. Results: Most of the victims i.e. 147 (40.83%) were young (15 to 30 years); from low i.e. 114 (31.66%) and mid i.e. 198 (55%) income families and were passengers i.e. 153 (42.50%) and pedestrians i.e. 105 (29.16%). Sever accidents leading to fatal outcome were associated with personal problems (P<0.01, χ2 - 8.03), recent or on-day conflicts (P<0.001, χ2 - 18.88) and some evidence of alcohol consumptions (P<0.001, χ2 - 30.25). Increased prevalence of RTA was also noticed at beginning i.e. 198 (55%) and end i.e. 69 (19.16%) of journey; in rainy and cloudy conditions (269 i.e. 74.72%) and in evening hours (3 to 7 p.m. 159 i.e. 44.16%). Out of 246 vehicles involved; 162 (65.85%) were old and ill maintained. The contributions of old vehicle to fatal injuries were 33 (50%). Head injury was found in 156 (43.33 %) cases and its associated case fatality rate was 90.90%. In spite of a good percentage receiving first aid i.e. 213 (59.16%) after RTA; there was a notable delay (174 i.e. 48.33% admitted after 6 h) in shifting the cases to the hospitals. The estimated total days lost due to hospital stay was 4620 with an average of 12.83 days per each case. Conclusion: Most

  5. Population studies: an integrated course in epidemiology and sociology for medical students.

    PubMed

    Elford, J; Chapman, G E; Boothroyd Brooks, E M; Shaper, A G

    1985-05-01

    At the Royal Free Hospital School of Medicine, London, an integrated course in epidemiology and sociology for preclinical students was introduced in 1979. The course--Population Studies--is taken by the 100 second-year medical students in the summer term before they enter their clinical years. It occupies one full day and one half day each week for 8 weeks--approximately 80 hours of tuition. Population Studies is unusual in two respects. Firstly, it introduces a substantial amount of epidemiology into the preclinical curriculum. And, secondly, this is the only London medical school to integrate the teaching of sociology and epidemiology into the one course.

  6. The impact of self-identified race on epidemiologic studies of gene expression.

    PubMed

    Sharma, Sunita; Murphy, Amy; Howrylak, Judie; Himes, Blanca; Cho, Michael H; Chu, Jen-Hwa; Hunninghake, Gary M; Fuhlbrigge, Anne; Klanderman, Barbara; Ziniti, John; Senter-Sylvia, Jody; Liu, Andy; Szefler, Stanley J; Strunk, Robert; Castro, Mario; Hansel, Nadia N; Diette, Gregory B; Vonakis, Becky M; Adkinson, N Franklin; Carey, Vincent J; Raby, Benjamin A

    2011-02-01

    Although population differences in gene expression have been established, the impact on differential gene expression studies in large populations is not well understood. We describe the effect of self-reported race on a gene expression study of lung function in asthma. We generated gene expression profiles for 254 young adults (205 non-Hispanic whites and 49 African Americans) with asthma on whom concurrent total RNA derived from peripheral blood CD4(+) lymphocytes and lung function measurements were obtained. We identified four principal components that explained 62% of the variance in gene expression. The dominant principal component, which explained 29% of the total variance in gene expression, was strongly associated with self-identified race (P<10(-16)). The impact of these racial differences was observed when we performed differential gene expression analysis of lung function. Using multivariate linear models, we tested whether gene expression was associated with a quantitative measure of lung function: pre-bronchodilator forced expiratory volume in one second (FEV(1)). Though unadjusted linear models of FEV(1) identified several genes strongly correlated with lung function, these correlations were due to racial differences in the distribution of both FEV(1) and gene expression, and were no longer statistically significant following adjustment for self-identified race. These results suggest that self-identified race is a critical confounding covariate in epidemiologic studies of gene expression and that, similar to genetic studies, careful consideration of self-identified race in gene expression profiling studies is needed to avoid spurious association.

  7. Air pollution exposure prediction approaches used in air pollution epidemiology studies

    EPA Science Inventory

    Epidemiological studies of the health effects of air pollution have traditionally relied upon surrogates of personal exposures, most commonly ambient concentration measurements from central-site monitors. However, this approach may introduce exposure prediction errors and miscla...

  8. Spot Sampling and Exposure Surrogate Selection as Sources of Bias in Environmental Epidemiology Studies

    EPA Science Inventory

    Spot measurements of chemical biomarkers are often used as quantitative exposure surrogates in environmental epidemiology studies. These measures can be expressed a number of different ways – for example, urinary biomarkers can be expressed in units of concentration (&micr...

  9. Development and Evaluation of Alternative Metrics of Ambient Air Pollution Exposure for Use in Epidemiologic Studies

    EPA Science Inventory

    Population-based epidemiologic studies of air pollution have traditionally relied upon imperfect surrogates of personal exposures, such as area-wide ambient air pollution levels based on readily available outdoor concentrations from central monitoring sites. This practice may in...

  10. Equivalency of risk for a modified health endpoint: a case from recreational water epidemiology studies

    EPA Science Inventory

    The United States Environmental Protection Agency (US EPA) and its predecessors have conducted three distinct series of epidemiological studies beginning in 1948 on the relationship between bathing water quality and swimmers' illnesses. Keeping pace with advances in microbial tec...

  11. Sources of uncertainty in epidemiological studies and their impact on human health risk assessments

    EPA Science Inventory

    ILSI’s Health and Environmental Science Institute identified the evaluation of causality in epidemiological studies as an emerging science priority in 2010. A multidisciplinary subcommittee of experts convened in Research Triangle Park, North Carolina in October of 2012 to ...

  12. 10 CFR 602.5 - Epidemiology and Other Health Studies Financial Assistance Program.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... toxic substances; (5) Epidemiology and other health studies relating to energy production, transmission... (7) Other systems or activities enhancing these areas, as well as other program areas as may...

  13. Apolipoprotein E in the genetics and epidemiology of Alzheimer`s disease

    SciTech Connect

    Hardy, J.

    1995-10-09

    The role of apolipoprotein E (ApoE) alleles and isoforms in the etiology and pathogenesis of Alzheimer`s disease is discussed. The possibility that ApoE itself is not involved in the disease pathogenesis but is merely in genetic disequilibrium with the real locus is discussed and dismissed. The data showing that the {epsilon}4 allele is associated with an increased risk of developing the disease and with an earlier onset age are reviewed. The data showing that, at least in some circumstances, the {epsilon}2 allele is associated with a decrease in the risk of developing the disease, and with a later onset age are also reviewed. Data from the genetic analysis of other disorders are reviewed and presented, and it is suggested that the genetic data support the notion that the role of ApoE in the etiology of the disease directly relates to {beta}-amyloid deposition and plaque formation. This suggestion is in concordance with the most likely mechanism for the role of P-amyloid precursor protein gene mutations as other risk factors for the disease. 68 refs.

  14. A nationwide study of the epidemiology of relapsing polychondritis

    PubMed Central

    Horváth, Anna; Páll, Nóra; Molnár, Katalin; Kováts, Tamás; Surján, György; Vicsek, Tamás; Pollner, Péter

    2016-01-01

    Objective Relapsing polychondritis (RP) is a rare autoimmune inflammatory disease that attacks mainly cartilaginous structures or causes serious damage in proteoglycan-rich structures (the eyes, heart, blood vessels, inner ear). This study shows results regarding the epidemiology, progression, and associations of this highly variable disease by collecting all cases from a 124-million-person-year Central European nationwide cohort. Methods We used the Hungarian Health Care Database to identify all persons with possible RP infection. We followed patients who had International Classification of Diseases 10th edition code M94.1 at least once in their inpatient or outpatient records between January 1, 2002 and December 31, 2013 in Hungary. We classified these patients into disease severity groups by their drug consumption patterns between January 1, 2010 and December 31, 2013. We analyzed the regional distribution of RP incidences as well. Overall maps of comorbidity are presented with network layouts. Results We identified 256 patients with RP among cumulatively 11.5 million registered inhabitants. We classified these patients into four severity classes as “extremely mild” (n=144), “mild” (n=22), “moderate” (n=41), and “severe” (n=4). Two additional groups were defined for patients without available drug data as “suspected only” (n=23) and “confirmed but unknown treatment” (n=22). The age and sex distributions of patients were similar to worldwide statistics. Indeed, the overall survival was good (95% confidence interval for 5 years was 83.6%–92.9% and for 10 years was 75.0%–88.3% which corresponds to the overall survival of the general population in Hungary), and the associations with other autoimmune disorders were high (56%) in Hungary. Almost any disease can occur with RP; however, the symptoms of chromosomal abnormalities are only incidental. Spondylosis can be a sign of the activation of RP, while Sjögren syndrome is the most frequent

  15. Molecular epidemiological and serological studies of bovine leukemia virus (BLV) infection in Thailand cattle.

    PubMed

    Lee, EunJung; Kim, Eun-Ju; Ratthanophart, Jadsada; Vitoonpong, Ratchaneekorn; Kim, Bo-Hye; Cho, In-Soo; Song, Jae-Young; Lee, Kyoung-Ki; Shin, Yeun-Kyung

    2016-07-01

    BLV is the etiological agent of enzootic bovine leucosis. BLV has negative effects on animal health and causes economic losses worldwide. However, epidemiological studies on BLV are relatively unknown in many parts of Asian countries. Thus, this study sought to explore BLV infections in cattle in Thailand to determine the extent of the geographic distribution of BLV and to measure its prevalence rates. For this study, 744 cattle from 11 farms in 9 provinces of Thailand were screened in 2013 and 2014 by ELISA and nested PCR. Of those cattle, 41 BLVs were genetically characterized using 188 BLV gp51 env gene sequences available in GenBank. The BLV prevalence in Thailand was high, ranging from 5.3% to 87.8%, as determined by PCR and 11.0% to 100% as determined by ELISA, according to geographical region. Phylogenetic analysis showed that Thailand BLVs belonged to genotypes 1 and 6 and a new genotype 10, which are sporadically observed across Thailand with a prevalence of 31.7%, 19.5%, and 48.8%, respectively. A significant number of amino acid substitutions were also found in the gp51 sequences, of which unique changes in genotype 10 have not been reported previously. Briefly, the majority of substitutions were confined to CD4+/CD8+ T-cell epitopes, neutralizing domains, and E-D-A epitopes. Those observations indicate that BLV infections in Thailand cattle are prevalent and that the geographic distribution of BLV is dynamic, with a high level of genetic diversity. This distribution implies a long-term BLV infection in cattle populations and the movement of infected cattle. In sum, this study suggests that intensive surveillance and effective prevention strategies are required to determine the prevalence of BLV in Thailand and control continuous infections with BLVs.

  16. Molecular epidemiological and serological studies of bovine leukemia virus (BLV) infection in Thailand cattle.

    PubMed

    Lee, EunJung; Kim, Eun-Ju; Ratthanophart, Jadsada; Vitoonpong, Ratchaneekorn; Kim, Bo-Hye; Cho, In-Soo; Song, Jae-Young; Lee, Kyoung-Ki; Shin, Yeun-Kyung

    2016-07-01

    BLV is the etiological agent of enzootic bovine leucosis. BLV has negative effects on animal health and causes economic losses worldwide. However, epidemiological studies on BLV are relatively unknown in many parts of Asian countries. Thus, this study sought to explore BLV infections in cattle in Thailand to determine the extent of the geographic distribution of BLV and to measure its prevalence rates. For this study, 744 cattle from 11 farms in 9 provinces of Thailand were screened in 2013 and 2014 by ELISA and nested PCR. Of those cattle, 41 BLVs were genetically characterized using 188 BLV gp51 env gene sequences available in GenBank. The BLV prevalence in Thailand was high, ranging from 5.3% to 87.8%, as determined by PCR and 11.0% to 100% as determined by ELISA, according to geographical region. Phylogenetic analysis showed that Thailand BLVs belonged to genotypes 1 and 6 and a new genotype 10, which are sporadically observed across Thailand with a prevalence of 31.7%, 19.5%, and 48.8%, respectively. A significant number of amino acid substitutions were also found in the gp51 sequences, of which unique changes in genotype 10 have not been reported previously. Briefly, the majority of substitutions were confined to CD4+/CD8+ T-cell epitopes, neutralizing domains, and E-D-A epitopes. Those observations indicate that BLV infections in Thailand cattle are prevalent and that the geographic distribution of BLV is dynamic, with a high level of genetic diversity. This distribution implies a long-term BLV infection in cattle populations and the movement of infected cattle. In sum, this study suggests that intensive surveillance and effective prevention strategies are required to determine the prevalence of BLV in Thailand and control continuous infections with BLVs. PMID:27090024

  17. Epigenetic Epidemiology: Promises for Public Health Research

    PubMed Central

    Bakulski, Kelly M.; Fallin, M. Daniele

    2014-01-01

    Epigenetic changes underlie developmental and age related biology. Promising epidemiologic research implicates epigenetics in disease risk and progression, and suggests epigenetic status depends on environmental risks as well as genetic predisposition. Epigenetics may represent a mechanistic link between environmental exposures, or genetics, and many common diseases, or may simply provide a quantitative biomarker for exposure or disease for areas of epidemiology currently lacking such measures. This great promise is balanced by issues related to study design, measurement tools, statistical methods, and biological interpretation that must be given careful consideration in an epidemiologic setting. This article describes the promises and challenges for epigenetic epidemiology, and suggests directions to advance this emerging area of molecular epidemiology. PMID:24449392

  18. Ischemic heart disease among the general Mongolian population: a review of epidemiological studies.

    PubMed

    Enkh-Oyun, Tsogzolbaatar; Kotani, Kazuhiko; Swanson, Eric

    2016-01-01

    Ischemic heart disease (IHD) is considered to be a pivotal health problem in Mongolia. To summarize the existing epidemiology of IHD in the general Mongolian population is crucial for primary prevention. The present review summarized population-based epidemiological data of IHD in Mongolia. When epidemiological studies were extracted from databases, very limited studies were available. The frequencies of IHD and IHD-attributable death rates appeared to be high and have an increased tendency in Mongolia. This could to be due to a gradually worsening state of potential IHD-related risk factors, such as smoking, hypertension, hypercholesterolemia, obesity and diabetes mellitus. This might indicate an urgent need of strategies for IHD and related risk factors. Anti-IHD strategies, such as more epidemiological studies and campaigns to increase awareness of IHD, at nationwide public health levels would be required in Mongolia for more effective prevention.

  19. Contributions of genetic studies to clinical psychiatry.

    PubMed

    Abe, K; Oda, N

    1991-12-01

    Recent twin and family studies have demonstrated a genetic factor in Gilles de la Tourette syndrome, some cases of infantile autism, enuresis, specific reading disability, sleepwalking, night terrors, common fears and anxiety. Family studies have been used to elucidate the nosological relationship of psychiatric disorders; e.g. anorexia nervosa (to affective disorder), Gilles de la Tourette syndrome, and sleeptalking. Advances in biochemical genetics and in enzyme polymorphisms suggest that there are wide individual variations in the adverse effects of drugs and that dosage should be tailored to the individual patient. Recently molecular genetic methods have been introduced to psychiatry, but a major breakthrough in this field appears to be still years away.

  20. A molecular epidemiological study of rabies in Cuba.

    PubMed

    Nadin-Davis, S A; Torres, G; Ribas, M De Los Angeles; Guzman, M; De La Paz, R Cruz; Morales, M; Wandeler, A I

    2006-12-01

    To investigate the emergence and current situation of terrestrial rabies in Cuba, a collection of rabies virus specimens was employed for genetic characterization. These data supported the monophyletic nature of all terrestrial rabies viruses presently circulating in Cuba but additionally delineated several distinct variants exhibiting limited spatial distribution which may reflect the history of rabies spread on the island. The strain of rabies currently circulating in Cuba, which emerged on the island in the early 20th century, has very close evolutionary ties to the Mexican dog type and is a member of the cosmopolitan lineage widely distributed during the colonial period. The Cuban rabies viruses, which circulate predominantly within the mongoose population, are phylogenetically distant from viruses circulating in mongooses in other parts of the world. These studies illustrate, at a global level, the adaptation of multiple strains of rabies to mongoose species which should be regarded as important wildlife hosts for rabies re-emergence. Given the recent emergence of human cases due to bat contact in Cuba, this study also included a single insectivorous bat specimen which was found to most closely resemble the rabies viruses known to circulate in Mexican vampire bats. PMID:16740188

  1. Identical twins in forensic genetics - Epidemiology and risk based estimation of weight of evidence.

    PubMed

    Tvedebrink, Torben; Morling, Niels

    2015-12-01

    The increase in the number of forensic genetic loci used for identification purposes results in infinitesimal random match probabilities. These probabilities are computed under assumptions made for rather simple population genetic models. Often, the forensic expert reports likelihood ratios, where the alternative hypothesis is assumed not to encompass close relatives. However, this approach implies that important factors present in real human populations are discarded. This approach may be very unfavourable to the defendant. In this paper, we discuss some important aspects concerning the closest familial relationship, i.e., identical (monozygotic) twins, when reporting the weight of evidence. This can be done even when the suspect has no knowledge of an identical twin or when official records hold no twin information about the suspect. The derived expressions are not original as several authors previously have published results accounting for close familial relationships. However, we revisit the discussion to increase the awareness among forensic genetic practitioners and include new information on medical and societal factors to assess the risk of not considering a monozygotic twin as the true perpetrator. If accounting for a monozygotic twin in the weight of evidence, it implies that the likelihood ratio is truncated at a maximal value depending on the prevalence of monozygotic twins and the societal efficiency of recognising a monozygotic twin. If a monozygotic twin is considered as an alternative proposition, then data relevant for the Danish society suggests that the threshold of likelihood ratios should approximately be between 150,000 and 2,000,000 in order to take the risk of an unrecognised identical, monozygotic twin into consideration. In other societies, the threshold of the likelihood ratio in crime cases may reach other, often lower, values depending on the recognition of monozygotic twins and the age of the suspect. In general, more strictly kept

  2. Identical twins in forensic genetics - Epidemiology and risk based estimation of weight of evidence.

    PubMed

    Tvedebrink, Torben; Morling, Niels

    2015-12-01

    The increase in the number of forensic genetic loci used for identification purposes results in infinitesimal random match probabilities. These probabilities are computed under assumptions made for rather simple population genetic models. Often, the forensic expert reports likelihood ratios, where the alternative hypothesis is assumed not to encompass close relatives. However, this approach implies that important factors present in real human populations are discarded. This approach may be very unfavourable to the defendant. In this paper, we discuss some important aspects concerning the closest familial relationship, i.e., identical (monozygotic) twins, when reporting the weight of evidence. This can be done even when the suspect has no knowledge of an identical twin or when official records hold no twin information about the suspect. The derived expressions are not original as several authors previously have published results accounting for close familial relationships. However, we revisit the discussion to increase the awareness among forensic genetic practitioners and include new information on medical and societal factors to assess the risk of not considering a monozygotic twin as the true perpetrator. If accounting for a monozygotic twin in the weight of evidence, it implies that the likelihood ratio is truncated at a maximal value depending on the prevalence of monozygotic twins and the societal efficiency of recognising a monozygotic twin. If a monozygotic twin is considered as an alternative proposition, then data relevant for the Danish society suggests that the threshold of likelihood ratios should approximately be between 150,000 and 2,000,000 in order to take the risk of an unrecognised identical, monozygotic twin into consideration. In other societies, the threshold of the likelihood ratio in crime cases may reach other, often lower, values depending on the recognition of monozygotic twins and the age of the suspect. In general, more strictly kept

  3. Design and analysis of metabolomics studies in epidemiologic research: a primer on -omic technologies.

    PubMed

    Tzoulaki, Ioanna; Ebbels, Timothy M D; Valdes, Ana; Elliott, Paul; Ioannidis, John P A

    2014-07-15

    Metabolomics is the field of "-omics" research concerned with the comprehensive characterization of the small low-molecular-weight metabolites in biological samples. In epidemiology, it represents an emerging technology and an unprecedented opportunity to measure environmental and other exposures with improved precision and far less measurement error than with standard epidemiologic methods. Advances in the application of metabolomics in large-scale epidemiologic research are now being realized through a combination of improved sample preparation and handling, automated laboratory and processing methods, and reduction in costs. The number of epidemiologic studies that use metabolic profiling is still limited, but it is fast gaining popularity in this area. In the present article, we present a roadmap for metabolomic analyses in epidemiologic studies and discuss the various challenges these data pose to large-scale studies. We discuss the steps of data preprocessing, univariate and multivariate data analysis, correction for multiplicity of comparisons with correlated data, and finally the steps of cross-validation and external validation. As data from metabolomic studies accumulate in epidemiology, there is a need for large-scale replication and synthesis of findings, increased availability of raw data, and a focus on good study design, all of which will highlight the potential clinical impact of metabolomics in this field. PMID:24966222

  4. Genetic and molecular genetic studies of murine and human lupus.

    PubMed

    Steinberg, A D; Klinman, D M; Kastner, D L; Seldin, M F; Gause, W C; Scribner, C L; Britten, J L; Siegel, J N; Mountz, J D

    1987-06-01

    Mice and humans with systemic lupus erythematosus (SLE) have been studied with regard to cellular, genetic and molecular genetic abnormalities. B cell hyperactivity and autoantibody production are the hallmarks of this illness. In humans with SLE, there is increased stem cell, B cell precursor and B cell proliferation. The same is true of NZB mice. In lpr/lpr and gld/gld mice, marked expansion of a subpopulation of T cells allows extrathymic terminal T cell maturation and secondary B cell hyperactivity. Androgens suppress these processes and polyclonal immune activators accelerate them. Three types of genes are identified: inducing genes, accelerating genes and background genes. These give rise to abnormal expression of various cellular oncogenes, T cell receptor genes and immunoglobulin genes. The data suggest that abnormal immune regulation plays a critical role in the development of SLE, with polyclonal B cell activation being common to both mice and humans with SLE. Different genetic and cellular abnormalities underlie the ultimate syndrome, the common denominator, generalized autoimmunity, that we call SLE.

  5. Epidemiologic, genetic, and clinical associations among phenotypically distinct populations of Leishmania (Viannia) in Colombia.

    PubMed

    Saravia, N G; Segura, I; Holguin, A F; Santrich, C; Valderrama, L; Ocampo, C

    1998-07-01

    Phenotypic characterization of 511 strains of Leishmania, subgenus Viannia, isolated from Colombian patients was conducted based on electrophoretic polymorphisms of 13 isoenzymes. Ninety-one Colombian strains of L. braziliensis were the most heterogeneous, constituting seven zymodemes while 397 L. panamensis and 22 L. guyanensis strains yielded five and three zymodemes, respectively. Phosphogluconate dehydrogenase, nucleoside hydrolase, and superoxide dismutase were the most polymorphic enzymes in this collection of strains, and together with glucose-6-phosphate dehydrogenase, allowed the discrimination of the three aforementioned species. Hierarchical cluster analysis of the zymodemes using Jaccard's coefficient of similarities revealed two clusters, one constituted by L. braziliensis zymodemes, and another by three subgroups consisting of zymodemes of L. panamensis closely related to the species reference strain, another consisting of L. guyanensis zymodemes, and a third group distinguished by new electromorphs of proline iminopeptidase and aspartate aminotransferase that reacted with the L. panamensis-specific monoclonal antibody B-11. Multiple zymodemes of L. panamensis and L. guyanensis were found to be sympatrically transmitted in foci along the Pacific coast. Leishmania braziliensis variants were ubiquitous throughout the territory of Colombia; L. panamensis was prevalent in the western region and L. guyanensis was prevalent in the Orinoco and Amazon river basins in the eastern half of the country. Distinct zymodemes of L. panamensis predominated in the northern and southern regions of the Pacific coast. Nine zymodemes of all three species were isolated from mucosal lesions. Zymodeme 1.1 of L. braziliensis had the highest frequency of mucosal involvement (10% of the cases), and disease caused by this zymodeme had the longest mean time of evolution (31 months; P = 0.002). In addition to being useful in describing epidemiologic relationships, the intraspecific

  6. Epidemiology of the American Indians' burden and its likely genetic origins.

    PubMed

    Carey, Martin C; Paigen, Beverly

    2002-10-01

    It was not known until recently whether the endemic of cholesterol gallstones among certain southwestern American Indian tribes was unique among this ethnic group. With use of ultrasonography of the gallbladder and standard diagnostic criteria, gallstones are now found in epidemic proportions in 13 diverse American Indian tribes and communities living in Arizona, Oklahoma, and the Dakotas. We speculate that this predisposition is polygenic involving "thrifty" genes that conferred survival advantages when Paleo-Indians migrated from present-day Siberia to the Americas during the last Great Ice Age approximately 50,000 to 10,000 years ago. A reasonable hypothesis is that functioning of these genes promoted more efficient calorie utilization and storage in the form of adipose tissue. Beneficial results would have been operative during the isolation of Paleo-Indians in the Bering Strait land bridge (Beringia) when thrifty genes would have ensured sufficient fat reserves for survival of prolonged winters, successful pregnancy outcomes, and extended lactation periods. The authors' conjoint work on genetics of experimental cholesterol cholelithiasis in inbred mice promises help in pinpointing orthologous genetic loci (LITH genes) in the human genome. Moreover, the shared environments and homogeneity of American Indian tribes and communities should facilitate discovery of the ensembles of their common and rarer cholesterol gallstone genes. It is anticipated that knowledge of expression, polymorphisms, and functionality of LITH genes will help resolve the molecular mechanisms of this complex heterogeneous trait and thereby provide targets for novel therapies to prevent cholesterol cholelithiasis worldwide. PMID:12297824

  7. Review of epidemiological studies on the occupational risk of tuberculosis in low-incidence areas.

    PubMed

    Seidler, Andreas; Nienhaus, Albert; Diel, Roland

    2005-01-01

    This review summarizes the epidemiological evidence for occupationally acquired tuberculosis and considers the implications for the prevention of tuberculosis. The relevant epidemiological studies were identified on the basis of the Medline data bank, starting with the year 1966. The evaluation of occupational groups with an elevated tuberculosis risk is exclusively based on epidemiologic studies of good or acceptable quality, applying clearly defined criteria of methodological quality. In summary, the available epidemiological evidence suggests that the risk of tuberculosis is elevated in the following occupational groups: hospital employees in wards with tuberculosis patients; nurses in hospitals; nurses attending HIV-positive or drug-addicted patients; pathology and laboratory workers; respiratory therapists and physiotherapists; physicians in internal medicine, anaesthesia, surgery and psychiatry; non-medical hospital personnel in housekeeping and transport work; funeral home employees, and prison employees. However, the epidemiological evidence is limited for all these occupations, with the exception of the nurses, because of the lack of methodologically adequate studies that have got the statistical power to differentiate between specific work tasks. There is a need for large population-based studies with precise definition of exposure, which should include molecular epidemiologic methods in the investigation of occupational risk factors of tuberculosis. PMID:16088290

  8. Epidemiologic Study of Blastocystis Infection in an Urban Community in the Philippines.

    PubMed

    Belleza, Maria Luz B; Cadacio, Jessa Louise C; Borja, Maridel P; Solon, Juan Antonio A; Padilla, Mildred A; Tongol-Rivera, Pilarita N; Rivera, Windell L

    2015-01-01

    Blastocystis has been considered as the most common intestinal parasite in humans and has an augmented impact on public health. However, the prevalence of this parasite in the Philippines has not been determined. To contribute to a better understanding of the epidemiology of this infection, a cross-sectional study aimed at providing the first documented data on the prevalence and correlates, sociodemographic factors, hygiene practices, source of water supply, and dog ownership, associated with Blastocystis infection was carried out in randomly selected communities at Pateros, Metro Manila. Fecal samples from respondents were collected and cultured in diphasic agar medium for 3-7 days and examined using light microscopy. Of the 1,271 respondents, 12.98% (95% CI: 11.13-14.83) were detected positive for Blastocystis. Among the correlates of Blastocystis infection, dog ownership was found significantly associated as confirmed by multivariate analysis. Therefore, this factor should be considered in information to create awareness about Blastocystis and to prevent and control Blastocystis infection in particular and diarrheal diseases in general. Further studies using molecular approaches to distinguish subtype and to determine genetic characteristics of isolates from humans and dogs are recommended to analyze their relationship and provide more conclusive evidence of cross-transmission. PMID:26074981

  9. Epidemiologic Study of Blastocystis Infection in an Urban Community in the Philippines

    PubMed Central

    Belleza, Maria Luz B.; Cadacio, Jessa Louise C.; Borja, Maridel P.; Solon, Juan Antonio A.; Padilla, Mildred A.; Tongol-Rivera, Pilarita N.; Rivera, Windell L.

    2015-01-01

    Blastocystis has been considered as the most common intestinal parasite in humans and has an augmented impact on public health. However, the prevalence of this parasite in the Philippines has not been determined. To contribute to a better understanding of the epidemiology of this infection, a cross-sectional study aimed at providing the first documented data on the prevalence and correlates, sociodemographic factors, hygiene practices, source of water supply, and dog ownership, associated with Blastocystis infection was carried out in randomly selected communities at Pateros, Metro Manila. Fecal samples from respondents were collected and cultured in diphasic agar medium for 3–7 days and examined using light microscopy. Of the 1,271 respondents, 12.98% (95% CI: 11.13–14.83) were detected positive for Blastocystis. Among the correlates of Blastocystis infection, dog ownership was found significantly associated as confirmed by multivariate analysis. Therefore, this factor should be considered in information to create awareness about Blastocystis and to prevent and control Blastocystis infection in particular and diarrheal diseases in general. Further studies using molecular approaches to distinguish subtype and to determine genetic characteristics of isolates from humans and dogs are recommended to analyze their relationship and provide more conclusive evidence of cross-transmission. PMID:26074981

  10. Epidemiologic Study of Blastocystis Infection in an Urban Community in the Philippines.

    PubMed

    Belleza, Maria Luz B; Cadacio, Jessa Louise C; Borja, Maridel P; Solon, Juan Antonio A; Padilla, Mildred A; Tongol-Rivera, Pilarita N; Rivera, Windell L

    2015-01-01

    Blastocystis has been considered as the most common intestinal parasite in humans and has an augmented impact on public health. However, the prevalence of this parasite in the Philippines has not been determined. To contribute to a better understanding of the epidemiology of this infection, a cross-sectional study aimed at providing the first documented data on the prevalence and correlates, sociodemographic factors, hygiene practices, source of water supply, and dog ownership, associated with Blastocystis infection was carried out in randomly selected communities at Pateros, Metro Manila. Fecal samples from respondents were collected and cultured in diphasic agar medium for 3-7 days and examined using light microscopy. Of the 1,271 respondents, 12.98% (95% CI: 11.13-14.83) were detected positive for Blastocystis. Among the correlates of Blastocystis infection, dog ownership was found significantly associated as confirmed by multivariate analysis. Therefore, this factor should be considered in information to create awareness about Blastocystis and to prevent and control Blastocystis infection in particular and diarrheal diseases in general. Further studies using molecular approaches to distinguish subtype and to determine genetic characteristics of isolates from humans and dogs are recommended to analyze their relationship and provide more conclusive evidence of cross-transmission.

  11. Endodontic Epidemiology

    PubMed Central

    Shahravan, Arash; Haghdoost, Ali Akbar

    2014-01-01

    Epidemiology is the study of disease distribution and factors determining or affecting it. Likewise, endodontic epidemiology can be defined as the science of studying the distribution pattern and determinants of pulp and periapical diseases; specially apical periodontitis. Although different study designs have been used in endodontics, researchers must pay more attention to study designs with higher level of evidence such as randomized clinical trials. PMID:24688577

  12. Epidemiology, pathophysiology and putative genetic basis of carbamazepine- and oxcarbazepine-induced hyponatremia.

    PubMed

    Berghuis, B; de Haan, G-J; van den Broek, M P H; Sander, J W; Lindhout, D; Koeleman, B P C

    2016-09-01

    The use of carbamazepine (CBZ) and oxcarbazepine (OXC) as first-line antiepileptic drugs in the treatment of focal epilepsy is limited by hyponatremia, a known adverse effect. Hyponatremia occurs in up to half of people taking CBZ or OXC and, although often assumed to be asymptomatic, it can lead to symptoms ranging from unsteadiness and mild confusion to seizures and coma. Hyponatremia is probably due to the antidiuretic properties of CBZ and OXC that are, at least partly, explained by stimulation of the vasopressin 2 receptor/aquaporin 2 pathway. No known genetic risk variants for CBZ- and OXC-induced hyponatremia exist, but likely candidate genes are part of the vasopressin water reabsorption pathway. PMID:27333872

  13. Studying genetic research participants: lessons from the "Learning About Research in North Carolina" study.

    PubMed

    Corbie-Smith, Giselle; Blumenthal, Connie; Henderson, Gail; Garrett, Joanne; Bussey-Jones, Jada; Moloney, Mairead; Sandler, Robert S; Lloyd, Stacey W; Dorrance, Jessica; Darter, Jane

    2008-08-01

    Given the prohibitive cost of recruiting large and diverse populations for genetic explorations in cancer research, there has been a call for genetic studies to engage existing cohorts of research participants. This strategy could lead to more efficient recruitment and potentially result in significant advances in the understanding of cancer etiology and treatment. The Learning About Research in North Carolina (LeARN) study responded to the National Human Genome Research Institute interest in research on how study participants from diverse populations who had participated in genetic research perceived the risks and benefits of participating in combined epidemiologic-genetic research, how well they understand the purpose of the research and the uses to which the research results may be put, and how involvement in such research affects perceptions of disease causality. In this article, we give an overview of the LeARN study, summarizing the methods we used, challenges we encountered, and lessons learned about recruiting participants who have previously participated in genetic research.

  14. Strengthening the Reporting of Observational Studies in Epidemiology—Nutritional Epidemiology (STROBE-nut): An Extension of the STROBE Statement

    PubMed Central

    Hawwash, Dana; Ocké, Marga C.; Berg, Christina; Forsum, Elisabet; Sonestedt, Emily; Wirfält, Elisabet; Åkesson, Agneta; Kolsteren, Patrick; Byrnes, Graham; De Keyzer, Willem; Van Camp, John; Slimani, Nadia; Cevallos, Myriam; Egger, Matthias; Huybrechts, Inge

    2016-01-01

    Background Concerns have been raised about the quality of reporting in nutritional epidemiology. Research reporting guidelines such as the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement can improve quality of reporting in observational studies. Herein, we propose recommendations for reporting nutritional epidemiology and dietary assessment research by extending the STROBE statement into Strengthening the Reporting of Observational Studies in Epidemiology—Nutritional Epidemiology (STROBE-nut). Methods and Findings Recommendations for the reporting of nutritional epidemiology and dietary assessment research were developed following a systematic and consultative process, coordinated by a multidisciplinary group of 21 experts. Consensus on reporting guidelines was reached through a three-round Delphi consultation process with 53 external experts. In total, 24 recommendations for nutritional epidemiology were added to the STROBE checklist. Conclusion When used appropriately, reporting guidelines for nutritional epidemiology can contribute to improve reporting of observational studies with a focus on diet and health. PMID:27270749

  15. Genetic Association Studies in Uterine Fibroids: Risk Alleles Presage the Path to Personalized Therapies.

    PubMed

    Gallagher, C Scott; Morton, Cynthia C

    2016-07-01

    Uterine leiomyoma (UL) is the most common tumor of the female reproductive system. Epidemiological analyses, including familial aggregation, twin studies, and racial discrepancies in disease prevalence and morbidity, indicated genetic factors influence risk for developing UL. Genome-wide association studies (GWASs) are a powerful method for identifying genetic variants that are associated with elevated risk for a common, complex disease. To date, three genome-wide scans for UL have been performed: a GWAS in Japanese women, a genome-wide linkage and association study in women of European decent, and an admixture-based analysis in African American women. Results from each of the three genome-wide scans performed have had varying success in identifying unique loci associated with predisposition to developing UL. Here, we address the evidence for a genetic basis for UL risk, discuss genetic association studies and their results, and identify challenges and future directions for UL GWAS analyses. PMID:27513025

  16. THE 1998 BALTIMORE PARTICULATE MATTER EPIDEMIOLOGY-EXPOSURE STUDY: PART 2-PERSONAL EXPOSURE ASSESSMENT ASSOCIATED WITH AN ELDERLY STUDY POPULATION

    EPA Science Inventory

    An integrated epidemiological-exposure panel study was conducted during the summer of 1998 which focused upon establishing relationships between potential human exposures to particulate matter (PM) and related co-pollutants with detectable health effects. The study design incor...

  17. Introduction and overview. Perinatal carcinogenesis: growing a node for epidemiology, risk management, and animal studies.

    PubMed

    Anderson, Lucy M

    2004-09-01

    Perinatal carcinogenesis as a cross-disciplinary concern is the subject of this special issue of Toxicology and Applied Pharmacology, which consists of a total of eight reviews or commentaries in the areas of epidemiology, risk assessment, and animal models. Some of the conclusions from these articles, and the Questions and Answers section that follows most of them, are summarized here. There is adequate reason to suspect that perinatal exposures contribute to human cancer risk, both childhood cancers, and those appearing later in life. The latter type of risk may actually be quantitatively the more important, and involve a wide range of types of effects, but has received only limited attention. With regard to childhood cancers, fetal irradiation and diethylstilbestrol exposure are known etiological agents, and it is likely, but not yet certain, there are additional external causes of a portion of these. Some current focal points of interest here include nitroso compounds, DNA topoisomerase inhibitors, viruses, anti-AIDS drugs, and endocrine disruptors. Regulatory agencies must rely heavily on animal data for estimation of human risk due to perinatal exposures to chemicals, and the quantity and quality of these data presently available for this purpose are greatly limiting. Correctly designed conventional animal studies with suspect chemicals are still needed. Furthermore, genetically engineered mouse models for childhood cancers, especially medulloblastoma, have become available, and could be used for screening of candidate causative agents for this cancer type, and for better understanding of gene-environment interactions. PMID:15313581

  18. Genetic features and molecular epidemiology of Enterococcus faecium isolated in two university hospitals in Brazil.

    PubMed

    da Silva, Leila Priscilla Pinheiro; Pitondo-Silva, André; Martinez, Roberto; da Costa Darini, Ana Lúcia

    2012-11-01

    The global emergence of vancomycin-resistant Enterococcus faecium (VREfm) has been characterized by a clonal spread of strains belonging to clonal complex 17 (CC17). Genetic features and clonal relationships of 53 VREfm isolated from patients in 2 hospitals in Ribeirao Preto, São Paulo, Brazil, during 2005-2010 were determined as a contribution to the Brazilian evolutionary history of these nosocomial pathogens. All isolates were daptomycin susceptible, vancomycin-resistant, and had the vanA gene. The predominant virulence genes were acm and esp. Only 5 VREfm isolated in 2005-2006 had intact Tn1546, while 81% showed Tn1546 with deleted left extremity and insertion of IS1251 between the vanS and vanH genes. Multilocus sequence typing analysis permitted the identification of 9 different sequence types (STs), with 5 being new ones (656, 657, 658, 659, and 660). Predominant STs were ST412 and ST478, all belonging to CC17, except ST658. This is the first report of the ST78 in Brazil. PMID:22959818

  19. Epidemiological situation and genetic analysis of H7N9 influenza viruses in Shanghai in 2013.

    PubMed

    Ge, Fei-Fei; Ju, Hou-Bin; Yang, De-Quan; Liu, Jian; Wang, Jian; Lu, Jun; Li, Xin; Zhang, Wei-Yi; Liu, Pei-Hong; Zhou, Jin-Ping

    2014-11-01

    The first reported human case of H7N9 influenza virus infection in Shanghai prompted a survey of local avian strains of influenza virus, involving the analysis of a large number of samples taken from poultry, wild birds, horses, pigs, dogs and mice. Seven instances of H7N9 virus infection were identified by real-time RT-PCR (1.47 % of samples), all in chickens sold in live-poultry markets. H7N9 antibody was not detected in serum samples collected from local poultry farms since 2006. The two H7N9 virus strains in the live-poultry markets and one H9N2 virus strain in the same market were genetically characterized. Resequencing of two of the seven isolates confirmed that they closely resembled H7N9 virus strains characterized elsewhere. Various strains co-exist in the same market, presenting a continuing risk of strain re-assortment. The closure of live-poultry markets has been an effective short-term means of minimizing human exposure to H7N9 virus. PMID:25085623

  20. Epidemiologic studies of polyomaviruses and cancer: previous findings, methodologic challenges and future directions.

    PubMed

    Rollison, Dana E M

    2006-01-01

    Polyomavirus infection became the focus of epidemiologic studies of cancer several decades ago, soon after the discovery of simian virus 40 (SV40) in 1960 and its ability to induce tumors in experimentally infected animals in 1961. Between 1963 and 2003, eight case-control and eleven cohort studies investigated the possible associations between polyomavirus infection and multiple types of cancer, including lymphoma, brain tumors, and mesothelioma. Two of these studies included measures of infection with the human polyomaviruses, JC virus and BK virus. Overall, the results from these studies were mostly null, although limitations in study design and exposure assessment complicate their interpretation. This chapter includes a review of results from previous epidemiologic studies of polyomavirus infection and human cancer, discussion of the methodologic challenges in study design, and proposed future directions for epidemiologic research.

  1. Genetic Simulation Tools for Post-Genome Wide Association Studies of Complex Diseases

    PubMed Central

    Amos, Christopher I.; Bafna, Vineet; Hauser, Elizabeth R.; Hernandez, Ryan D.; Li, Chun; Liberles, David A.; McAllister, Kimberly; Moore, Jason H.; Paltoo, Dina N.; Papanicolaou, George J.; Peng, Bo; Ritchie, Marylyn D.; Rosenfeld, Gabriel; Witte, John S.

    2014-01-01

    Genetic simulation programs are used to model data under specified assumptions to facilitate the understanding and study of complex genetic systems. Standardized data sets generated using genetic simulation are essential for the development and application of novel analytical tools in genetic epidemiology studies. With continuing advances in high-throughput genomic technologies and generation and analysis of larger, more complex data sets, there is a need for updating current approaches in genetic simulation modeling. To provide a forum to address current and emerging challenges in this area, the National Cancer Institute (NCI) sponsored a workshop, entitled “Genetic Simulation Tools for Post-Genome Wide Association Studies of Complex Diseases” at the National Institutes of Health (NIH) in Bethesda, Maryland on March 11-12, 2014. The goals of the workshop were to: (i) identify opportunities, challenges and resource needs for the development and application of genetic simulation models; (ii) improve the integration of tools for modeling and analysis of simulated data; and (iii) foster collaborations to facilitate development and applications of genetic simulation. During the course of the meeting the group identified challenges and opportunities for the science of simulation, software and methods development, and collaboration. This paper summarizes key discussions at the meeting, and highlights important challenges and opportunities to advance the field of genetic simulation. PMID:25371374

  2. Genetic simulation tools for post-genome wide association studies of complex diseases.

    PubMed

    Chen, Huann-Sheng; Hutter, Carolyn M; Mechanic, Leah E; Amos, Christopher I; Bafna, Vineet; Hauser, Elizabeth R; Hernandez, Ryan D; Li, Chun; Liberles, David A; McAllister, Kimberly; Moore, Jason H; Paltoo, Dina N; Papanicolaou, George J; Peng, Bo; Ritchie, Marylyn D; Rosenfeld, Gabriel; Witte, John S; Gillanders, Elizabeth M; Feuer, Eric J

    2015-01-01

    Genetic simulation programs are used to model data under specified assumptions to facilitate the understanding and study of complex genetic systems. Standardized data sets generated using genetic simulation are essential for the development and application of novel analytical tools in genetic epidemiology studies. With continuing advances in high-throughput genomic technologies and generation and analysis of larger, more complex data sets, there is a need for updating current approaches in genetic simulation modeling. To provide a forum to address current and emerging challenges in this area, the National Cancer Institute (NCI) sponsored a workshop, entitled "Genetic Simulation Tools for Post-Genome Wide Association Studies of Complex Diseases" at the National Institutes of Health (NIH) in Bethesda, Maryland on March 11-12, 2014. The goals of the workshop were to (1) identify opportunities, challenges, and resource needs for the development and application of genetic simulation models; (2) improve the integration of tools for modeling and analysis of simulated data; and (3) foster collaborations to facilitate development and applications of genetic simulation. During the course of the meeting, the group identified challenges and opportunities for the science of simulation, software and methods development, and collaboration. This paper summarizes key discussions at the meeting, and highlights important challenges and opportunities to advance the field of genetic simulation.

  3. A clinico-epidemiological study of epidemic typhus in Africa.

    PubMed

    Perine, P L; Chandler, B P; Krause, D K; McCardle, P; Awoke, S; Habte-Gabr, E; Wisseman, C L; McDade, J E

    1992-05-01

    Epidemic, louse-borne typhus persists in the rugged, mountainous areas of Ethiopia and much of northeastern and central Africa as well as in the rural highlands of Central and South America, where the conditions of living favor the harboring of body lice and where antibiotic treatment and effective louse-control measures are unavailable. The historical significance and current epidemiology of typhus, including the reservoir of Rickettsia prowazekii in flying squirrels in the United States, are reviewed, and the clinical presentation, laboratory findings, and hospital course in the cases of 60 patients admitted with epidemic, louse-borne typhus to the St. Paul's Hospital in Addis Ababa, Ethiopia, are described. Treatment of this disease with oral doxycycline, tetracycline, or chloramphenicol prevents complications and results in prompt resolution of symptoms. PMID:1600020

  4. Studies in epidemiology of maedi/visna in sheep.

    PubMed

    De Boer, G F; Terpstra, C; Houwers, D J; Hendriks, J

    1979-03-01

    Lambs born to ewes from flocks with a high incidence of maedi/visna were separated from their dams at birth (group 1), or after 10 h (group 2), six weeks (group 3) or one year (group 4) and were observed for periods of up to eight years. Group 1 lambs remained free of infection while 28 per cent, 76 per cent and 81 per cent respectively of lambs in the other groups developed clinical, serological or histopathological evidence of infection during the observation period. It is therefore concluded that vertical transmission, if it occurs at all, is of little significance in the epidemiology of the disease. The number of serologically, virologically and histopathologically maedi/visna positive sheep, the time of onset of disease and the severity of lesions were related to the duration of exposure to the parent flock. In a separate trial no evidence was obtained for the transmission of maedi/visna by Muellerius capillaris larvae. PMID:233619

  5. A systematic review of population based epidemiological studies in Myasthenia Gravis

    PubMed Central

    2010-01-01

    Background The aim was to collate all myasthenia gravis (MG) epidemiological studies including AChR MG and MuSK MG specific studies. To synthesize data on incidence rate (IR), prevalence rate (PR) and mortality rate (MR) of the condition and investigate the influence of environmental and technical factors on any trends or variation observed. Methods Studies were identified using multiple sources and meta-analysis performed to calculate pooled estimates for IR, PR and MR. Results 55 studies performed between 1950 and 2007 were included, representing 1.7 billion population-years. For All MG estimated pooled IR (eIR): 5.3 per million person-years (C.I.:4.4, 6.1), range: 1.7 to 21.3; estimated pooled PR: 77.7 per million persons (C.I.:64.0, 94.3), range 15 to 179; MR range 0.1 to 0.9 per millions person-years. AChR MG eIR: 7.3 (C.I.:5.5, 7.8), range: 4.3 to 18.0; MuSK MG IR range: 0.1 to 0.32. However marked variation persisted between populations studied with similar methodology and in similar areas. Conclusions We report marked variation in observed frequencies of MG. We show evidence of increasing frequency of MG with year of study and improved study quality. This probably reflects improved case ascertainment. But other factors must also influence disease onset resulting in the observed variation in IR across geographically and genetically similar populations. PMID:20565885

  6. An echovirus 18-associated outbreak of aseptic meningitis in Taiwan: epidemiology and diagnostic and genetic aspects.

    PubMed

    Tsai, Huey-Pin; Huang, Sheng-Wen; Wu, Feng-Ling; Kuo, Pin-Hwa; Wang, Shih-Min; Liu, Ching-Chuan; Su, Ih-Jen; Wang, Jen-Ren

    2011-09-01

    In 2006, an outbreak of aseptic meningitis was noted in Taiwan. From January to October 2006, a total of 3283 specimens collected from patients with viral infection, including 173 cerebrospinal fluid (CSF) samples, were examined for virus isolation and identification. Overall, 339 enterovirus (EV)-positive cases were identified by virus culture: echovirus 18 (E18) formed the majority (27.4 %, 93 cases), followed by coxsackievirus B2 (13.8 %, 47 cases) and coxsackievirus A2 (10.8 %, 37 cases). The manifestations of the 93 E18 cases were aseptic meningitis (44.1 %), viral exanthema (23.6 %), acute tonsillitis (15.1 %), acute pharyngitis (14.0 %), acute gastritis (11.8 %), herpangina (7.5 %) and bronchopneumonia (5.3 %). Of 107 E18 isolates identified, 100, 62.5 and 19 % were obtained following culture in RD, MRC-5 and A549 cells, respectively. E18 was identified most frequently from throat swabs (67.2 %) and less frequently from stool samples (15.9 %) and CSF (16.8 %). The detection rate of E18 was 78.2 % from CSF, 50 % from stool samples and 22.9 % from throat swabs. Phylogenetic relationships among the E18 strains were examined. Analysis of the partial VP1 gene showed 3.7-23.8 % variation in sequence compared with sequences from GenBank and, notably, the amino acid change V152S was detected in a protruding loop within the VP1 protein. These results indicate that a genetic variant of E18 was circulating and caused an outbreak of aseptic meningitis in Taiwan in 2006. PMID:21546563

  7. An echovirus 18-associated outbreak of aseptic meningitis in Taiwan: epidemiology and diagnostic and genetic aspects.

    PubMed

    Tsai, Huey-Pin; Huang, Sheng-Wen; Wu, Feng-Ling; Kuo, Pin-Hwa; Wang, Shih-Min; Liu, Ching-Chuan; Su, Ih-Jen; Wang, Jen-Ren

    2011-09-01

    In 2006, an outbreak of aseptic meningitis was noted in Taiwan. From January to October 2006, a total of 3283 specimens collected from patients with viral infection, including 173 cerebrospinal fluid (CSF) samples, were examined for virus isolation and identification. Overall, 339 enterovirus (EV)-positive cases were identified by virus culture: echovirus 18 (E18) formed the majority (27.4 %, 93 cases), followed by coxsackievirus B2 (13.8 %, 47 cases) and coxsackievirus A2 (10.8 %, 37 cases). The manifestations of the 93 E18 cases were aseptic meningitis (44.1 %), viral exanthema (23.6 %), acute tonsillitis (15.1 %), acute pharyngitis (14.0 %), acute gastritis (11.8 %), herpangina (7.5 %) and bronchopneumonia (5.3 %). Of 107 E18 isolates identified, 100, 62.5 and 19 % were obtained following culture in RD, MRC-5 and A549 cells, respectively. E18 was identified most frequently from throat swabs (67.2 %) and less frequently from stool samples (15.9 %) and CSF (16.8 %). The detection rate of E18 was 78.2 % from CSF, 50 % from stool samples and 22.9 % from throat swabs. Phylogenetic relationships among the E18 strains were examined. Analysis of the partial VP1 gene showed 3.7-23.8 % variation in sequence compared with sequences from GenBank and, notably, the amino acid change V152S was detected in a protruding loop within the VP1 protein. These results indicate that a genetic variant of E18 was circulating and caused an outbreak of aseptic meningitis in Taiwan in 2006.

  8. Australian empirical study into genetic discrimination.

    PubMed

    Otlowski, Margaret F; Taylor, Sandra D; Barlow-Stewart, Kristine K

    2002-01-01

    This paper outlines a major empirical study that is being undertaken by an interdisciplinary team into genetic discrimination in Australia. The 3-year study will examine the nature and extent of this newly emerging phenomenon across the perspectives of consumers, third parties, and the legal system and will analyze its social and legal dimensions. Although the project is confined to Australia, it is expected that the outcomes will have significance for the wider research community as this is the most substantial study of its kind to be undertaken to date into genetic discrimination. PMID:12394353

  9. Strategies to optimize the impact of nutritional surveys and epidemiological studies.

    PubMed

    Webb, Densie; Leahy, Margaret M; Milner, John A; Allison, David B; Dodd, Kevin W; Gaine, P Courtney; Matthews, Robert A J; Schneeman, Barbara O; Tucker, Katherine L; Young, S Stanley

    2013-01-01

    The development of nutrition and health guidelines and policies requires reliable scientific information. Unfortunately, theoretical considerations and empirical evidence indicate that a large percentage of science-based claims rely on studies that fail to replicate. The session "Strategies to Optimize the Impact of Nutrition Surveys and Epidemiological Studies" focused on the elements of design, interpretation, and communication of nutritional surveys and epidemiological studies to enhance and encourage the production of reliable, objective evidence for use in developing dietary guidance for the public. The speakers called for more transparency of research, raw data, consistent data-staging techniques, and improved data analysis. New approaches to collecting data are urgently needed to increase the credibility and utility of findings from nutrition epidemiological studies. Such studies are critical for furthering our knowledge and understanding of the effects of diet on health. PMID:24038252

  10. Brief Report: Negative Controls to Detect Selection Bias and Measurement Bias in Epidemiologic Studies

    PubMed Central

    Ercumen, Ayse; Benjamin-Chung, Jade; Colford, John M.

    2016-01-01

    Biomedical laboratory experiments routinely use negative controls to identify possible sources of bias, but epidemiologic studies have infrequently used this type of control in their design or measurement approach. Recently, epidemiologists proposed the routine use of negative controls in observational studies and defined the structure of negative controls to detect bias due to unmeasured confounding. We extend this previous study and define the structure of negative controls to detect selection bias and measurement bias in both observational studies and randomized trials. We illustrate the strengths and limitations of negative controls in this context using examples from the epidemiologic literature. Given their demonstrated utility and broad generalizability, the routine use of prespecified negative controls will strengthen the evidence from epidemiologic studies. PMID:27182642

  11. Leveraging epidemiologic and clinical collections for genomic studies of complex traits

    PubMed Central

    Crawford, Dana C.; Goodloe, Robert; Farber-Eger, Eric; Boston, Jonathan; Pendergrass, Sarah A.; Haines, Jonathan L.; Ritchie, Marylyn D.; Bush, William S.

    2015-01-01

    Background/Aims Present day limited resources demand DNA and phenotyping alternatives to the traditional prospective population-based epidemiologic collections. Methods To accelerate genomic discovery with an emphasis on diverse populations, we as part of the Epidemiologic Architecture for Genes Linked to Environment (EAGLE) study accessed all non-European American samples (n=15,863) available in BioVU, the Vanderbilt University biorepository linked to de-identified electronic medical records, for genomic studies as part of the larger Population Architecture using Genomics and Epidemiology (PAGE) I Study. Given previous studies have cautioned against the secondary use of clinically collected data compared with epidemiologically-collected data, we present here a characterization of EAGLE BioVU, including the billing and diagnostic (ICD-9) code distributions for adult and pediatric patients as well as comparisons made for select health metrics (body mass index, glucose, HbA1c, HDL-C, LDL-C, and triglycerides) with the population-based National Health and Nutrition Examination Surveys (NHANES) linked to DNA samples (NHANES III; n=7,159 and NHANES 1999–2002; n=7,839). Results Overall, the distributions of billing and diagnostic codes suggest this clinical sample is mixture of healthy and sick patients like that expected for a contemporary American population. Conclusion Little bias is observed among health metrics suggesting this clinical collection is suitable for genomic studies along with traditional epidemiologic cohorts. PMID:26201699

  12. Epidemiological and molecular characteristics of meticillin-resistant Staphylococcus aureus in Turkey: A multicentre study.

    PubMed

    Dündar, Devrim; Willke, Ayse; Sayan, Murat; Koc, Meliha Meric; Akan, Ozay Arıkan; Sumerkan, Bulent; Saltoglu, Nese; Yaman, Akgun; Ayaz, Celal; Koksal, Iftihar

    2016-09-01

    The aim of this study was to investigate the epidemiological and molecular features of clinical meticillin-resistant Staphylococcus aureus (MRSA) isolates in Turkey. MRSA isolates were collected from six regions of Turkey. The mecA and nuc genes were detected by PCR. Antimicrobial susceptibilities were determined by the disk diffusion method. Staphylococcal cassette chromosome mec (SCCmec) and staphylococcal protein A (spa) typing were performed by the sequencing method for 270 randomly selected MRSA isolates. The US Centers for Disease Control and Prevention (CDC) definition was used for epidemiological diagnosis of community-associated MRSA (CA-MRSA). Resistance rates of MRSA to ciprofloxacin, gentamicin, clindamycin, erythromycin, rifampicin, trimethoprim/sulfamethoxazole and tetracycline were 93.4%, 81.2%, 38.5%, 57.8%, 93.9%, 1.1% and 93.1%, respectively. The most frequent SCCmec type was SCCmec III (91.1%). SCCmec type IV was found in 5.2% of the isolates. The most frequent spa type was t030 (81.1%). Five isolates were CA-MRSA if only the epidemiological definition was used (5/725; 0.7%). Two isolates were defined as CA-MRSA both by epidemiological features and SCCmec typing (2/270; 0.7%). Of 14 SCCmec type IV isolates, 12 were not defined as CA-MRSA by epidemiological features. In conclusion, this is the most comprehensive multicentre study in Turkey investigating MRSA using both epidemiological and genotypic features. The CA-MRSA rate is low in Turkey. Combined use of epidemiological and genotypic methods is the most accurate approach for the diagnosis of CA-MRSA.

  13. Family and Psychosocial Risk Factors in a Longitudinal Epidemiological Study of Adolescents.

    ERIC Educational Resources Information Center

    Cuffe, Steven P.; McKeown, Robert E.; Addy, Cheryl L.; Garrison, Carol Z.

    2005-01-01

    Objective: To study the association of family and social risk factors with psychopathology in a longitudinal study of adolescents. Method: From 1986 to 1988, 3,419 seventh through ninth graders were screened with the Center for Epidemiologic Studies Depression Scale. The top decile scorers and a random sample of the remainder were interviewed…

  14. The future for genetic studies in reproduction

    PubMed Central

    Montgomery, G.W.; Zondervan, K.T.; Nyholt, D.R.

    2014-01-01

    Genetic factors contribute to risk of many common diseases affecting reproduction and fertility. In recent years, methods for genome-wide association studies (GWAS) have revolutionized gene discovery for common traits and diseases. Results of GWAS are documented in the Catalog of Published Genome-Wide Association Studies at the National Human Genome Research Institute and report over 70 publications for 32 traits and diseases associated with reproduction. These include endometriosis, uterine fibroids, age at menarche and age at menopause. Results that pass appropriate stringent levels of significance are generally well replicated in independent studies. Examples of genetic variation affecting twinning rate, infertility, endometriosis and age at menarche demonstrate that the spectrum of disease-related variants for reproductive traits is similar to most other common diseases. GWAS ‘hits’ provide novel insights into biological pathways and the translational value of these studies lies in discovery of novel gene targets for biomarkers, drug development and greater understanding of environmental factors contributing to disease risk. Results also show that genetic data can help define sub-types of disease and co-morbidity with other traits and diseases. To date, many studies on reproductive traits have used relatively small samples. Future genetic marker studies in large samples with detailed phenotypic and clinical information will yield new insights into disease risk, disease classification and co-morbidity for many diseases associated with reproduction and infertility. PMID:23982303

  15. Reporting genetic results in research studies: summary and recommendations of an NHLBI working group.

    PubMed

    Bookman, Ebony B; Langehorne, Aleisha A; Eckfeldt, John H; Glass, Kathleen C; Jarvik, Gail P; Klag, Michael; Koski, Greg; Motulsky, Arno; Wilfond, Benjamin; Manolio, Teri A; Fabsitz, Richard R; Luepker, Russell V

    2006-05-15

    Prospective epidemiologic studies aid in identifying genetic variants associated with diseases, health risks, and physiologic traits. These genetic variants may eventually be measured clinically for purposes of diagnosis, prognosis, and treatment. As evidence of the potential clinical value of such information accrues, research studies face growing pressure to report these results to study participants or their physicians, even before sufficient evidence is available to support widespread screening of asymptomatic persons. There is thus a need to begin to develop consensus on whether and when genetic findings should be reported to participants in research studies. The National Heart, Lung, and Blood Institute (NHLBI) convened a Working Group on Reporting Genetic Results in Research Studies to discuss if, when, and how genetic information should be reported to study participants. The Working Group concluded that genetic test results should be reported to study participants when the associated risk for the disease is significant; the disease has important health implications such as premature death or substantial morbidity or has significant reproductive implications; and proven therapeutic or preventive interventions are available. Finally, the Working Group recommended procedures for reporting genetic research results and encouraged increased efforts to create uniform guidelines for this activity.

  16. Epidemiology and genetics of cystic fibrosis in Asia: In preparation for the next-generation treatments.

    PubMed

    Singh, Meenu; Rebordosa, Cristina; Bernholz, Juliane; Sharma, Neeraj

    2015-11-01

    Cystic fibrosis (CF) in the Asian population is less frequently reported due to under-diagnosis and lack of centralized CF patient registries. Clinical studies on CF cases from Asia have documented a severe course of the disease. The spectrum of the cystic fibrosis transmembrane conductance regulator (CFTR) variants in this population is quite heterogeneous. In total, 166 variants have been reported on approximately 3700 Asian CF chromosomes. The frequency of F508del among Asians is low compared with Caucasians. Recent in vitro studies have shown promise of small molecule correction and potentiation of 45 different CFTR variants. Of these variants, 16 (including G551D and F508del) have also been observed among Asian CF individuals. We suggest undertaking molecular studies extensively to annotate CFTR variants that will help Asian CF individuals to benefit from the precision medicine gaining momentum in the Western countries.

  17. Mendelian randomization in (epi)genetic epidemiology: an effective tool to be handled with care.

    PubMed

    Latvala, Antti; Ollikainen, Miina

    2016-01-01

    A study examining blood lipid traits takes epigenomics approaches to the next level by using carefully performed Mendelian randomization to assess causality rather than simply reporting associations.See related research article: http://genomebiology.biomedcentral.com/articles/10.1186/s13059-016-1000-6. PMID:27418254

  18. Posttraumatic stress disorder and physical illness: results from clinical and epidemiologic studies.

    PubMed

    Boscarino, Joseph A

    2004-12-01

    Research indicates that exposure to traumatic stressors and psychological trauma is widespread. The association of such exposures with posttraumatic stress disorder (PTSD) and other mental health conditions is well known. However, epidemiologic research increasingly suggests that exposure to these events is related to increased health care utilization, adverse health outcomes, the onset of specific diseases, and premature death. To date, studies have linked traumatic stress exposures and PTSD to such conditions as cardiovascular disease, diabetes, gastrointestinal disease, fibromyalgia, chronic fatigue syndrome, musculoskeletal disorders, and other diseases. Evidence linking cardiovascular disease and exposure to psychological trauma is particularly strong and has been found consistently across different populations and stressor events. In addition, clinical studies have suggested the biological pathways through which stressor-induced diseases may be pathologically expressed. In particular, recent studies have implicated the hypothalamic-pituitary-adrenal (HPA) and the sympathetic-adrenal-medullary (SAM) stress axes as key in this pathogenic process, although genetic and behavioral/psychological risk factors cannot be ruled out. Recent findings, indicating that victims of PTSD have higher circulating T-cell lymphocytes and lower cortisol levels, are intriguing and suggest that chronic sufferers of PTSD may be at risk for autoimmune diseases. To test this hypothesis, we assessed the association between chronic PTSD in a national sample of 2,490 Vietnam veterans and the prevalence of common autoimmune diseases, including rheumatoid arthritis, psoriasis, insulin-dependent diabetes, and thyroid disease. Our analyses suggest that chronic PTSD, particularly comorbid PTSD or complex PTSD, is associated with all of these conditions. In addition, veterans with comorbid PTSD were more likely to have clinically higher T-cell counts, hyperreactive immune responses on

  19. Pericentric Inversion of Human Chromosome 9 Epidemiology Study in Czech Males and Females.

    PubMed

    Šípek, A; Panczak, A; Mihalová, R; Hrčková, L; Suttrová, E; Sobotka, V; Lonský, P; Kaspříková, N; Gregor, V

    2015-01-01

    Pericentric inversion of human chromosome 9 [inv(9)] is a relatively common cytogenetic finding. It is largely considered a clinically insignificant variant of the normal human karyotype. However, numerous studies have suggested its possible association with certain pathologies, e.g., infertility, habitual abortions or schizophrenia. We analysed the incidence of inv(9) and the spectrum of clinical indications for karyotyping among inv(9) carriers in three medical genetics departments in Prague. In their cytogenetic databases, among 26,597 total records we identified 421 (1.6 %) cases of inv(9) without any concurrent cytogenetic pathology. This study represents the world's largest epidemiological study on inv(9) to date. The incidence of inv(9) calculated in this way from diagnostic laboratory data does not differ from the incidence of inv(9) in three specific populationbased samples of healthy individuals (N = 4,166) karyotyped for preventive (amniocentesis for advanced maternal age, gamete donation) or legal reasons (children awaiting adoption). The most frequent clinical indication in inv(9) carriers was "idiopathic reproductive failure" - 37.1 %. The spectra and percentages of indications in individuals with inv(9) were further statistically evaluated for one of the departments (N = 170) by comparing individuals with inv(9) to a control group of 661 individuals with normal karyotypes without this inversion. The proportion of clinical referrals for "idiopathic reproductive failure" among inv(9) cases remains higher than in controls, but the difference is not statistically significant for both genders combined. Analysis in separated genders showed that the incidence of "idiopathic reproductive failure" could differ among inv(9) female and male carriers.

  20. Epidemiologic Behavior of Obesity in the Maracaibo City Metabolic Syndrome Prevalence Study

    PubMed Central

    Bermúdez, Valmore; Pacheco, Maikol; Rojas, Joselyn; Córdova, Evelyn; Velázquez, Rossibel; Carrillo, Daniela; Parra, María G.; Toledo, Alexandra; Añez, Roberto; Fonseca, Eneida; Marcano, Rafael París; Cano, Clímaco; Miranda, José López

    2012-01-01

    Introduction Obesity is a worldwide public health issue. Since the epidemiological behaviour of this disease is not well established in our country, the purpose of this study was to determinate its prevalence in the Maracaibo City, Zulia State- Venezuela. Materials and Methods A cross-sectional study was undertaken using the data set from the Maracaibo City Metabolic Syndrome Prevalence Study. The sample consists of 2108 individuals from both genders and randomly selected: 1119 (53.09%) women and 989 (46.91%) men. The participants were interrogated for a complete clinical history and anthropometric measurements. To classify obesity, the WHO criteria for Body Mass Index (BMI), and Waist Circumference (WC) from the IDF/NHLBI/AHA/WHF/IAS/IASO-2009 (IDF-2009) and ATPIII statements were applied. Results For BMI, obesity had an overall prevalence of 33.3% (n = 701), and according to gender women had 32.4% (n = 363) and men had 34.2% (n = 338). Overweight had a prevalence of 34.8% (n = 733), Normal weight had 29.8% (n = 629), and Underweight had 2.1% (n = 45). Adding Obesity and Overweight results, the prevalence of elevated BMI (>25 Kg/m2) was 68.1%. Using the IDF-2009 WC's cut-off, Obesity had 74.2% prevalence, compared to 51.7% using the ATPIII parameters. Conclusions These results show a high prevalence of abdominal obesity in our locality defined by the WHO, IDF-2009 and ATPIII criteria, which were not designed for Latin-American populations. We suggest further investigation to estimate the proper values according to ethnicity, genetic background and sociocultural aspects. PMID:22530014

  1. Molecular epidemiology and population genetics of Salmonella subspecies diarizonae in sheep in Norway and Sweden.

    PubMed Central

    Alvseike, O.; Vardund, T.; Lindstedt, B.; Heir, E.; Eriksson, E.; Kapperud, G.

    2004-01-01

    Fifty-four isolates of Salmonella enterica subsp. diarizonae (IIIb) in Norway, Sweden, England, the United States, France and Australia were characterized by pulsed-field gel electrophoresis (PFGE). This study focuses on serovar 61:k:1,5,(7) [S. IIIb 61:k:1,5,(7)] isolated from sheep. Digestion of the bacterial DNA with restriction enzyme XhaI yielded 15 distinct PFGE profiles comprising 12-16 fragments in the range 48.5-630.5 kbp. Four different profiles were identified in Norwegian sheep isolates and a single profile in Swedish isolates. The spatial and temporal distribution of profiles is discussed. PMID:15061500

  2. Genetic studies in the Amish community.

    PubMed

    Patton, Michael A

    2005-01-01

    The Amish community was established in Pennsylvania, Ohio and Indiana. They form a distinct and biologically isolated community by virtue of their strong cultural and religious beliefs. This paper outlines aspects of the Amish culture and reviews some of the recent genetic studies that have been undertaken in this community. PMID:16096212

  3. Scientific Statement on the Diagnostic Criteria, Epidemiology, Pathophysiology, and Molecular Genetics of Polycystic Ovary Syndrome.

    PubMed

    Dumesic, Daniel A; Oberfield, Sharon E; Stener-Victorin, Elisabet; Marshall, John C; Laven, Joop S; Legro, Richard S

    2015-10-01

    Polycystic ovary syndrome (PCOS) is a heterogeneous and complex disorder that has both adverse reproductive and metabolic implications for affected women. However, there is generally poor understanding of its etiology. Varying expert-based diagnostic criteria utilize some combination of oligo-ovulation, hyperandrogenism, and the presence of polycystic ovaries. Criteria that require hyperandrogenism tend to identify a more severe reproductive and metabolic phenotype. The phenotype can vary by race and ethnicity, is difficult to define in the perimenarchal and perimenopausal period, and is exacerbated by obesity. The pathophysiology involves abnormal gonadotropin secretion from a reduced hypothalamic feedback response to circulating sex steroids, altered ovarian morphology and functional changes, and disordered insulin action in a variety of target tissues. PCOS clusters in families and both female and male relatives can show stigmata of the syndrome, including metabolic abnormalities. Genome-wide association studies have identified a number of candidate regions, although their role in contributing to PCOS is still largely unknown.

  4. Scientific Statement on the Diagnostic Criteria, Epidemiology, Pathophysiology, and Molecular Genetics of Polycystic Ovary Syndrome

    PubMed Central

    Dumesic, Daniel A.; Oberfield, Sharon E.; Stener-Victorin, Elisabet; Marshall, John C.; Laven, Joop S.

    2015-01-01

    Polycystic ovary syndrome (PCOS) is a heterogeneous and complex disorder that has both adverse reproductive and metabolic implications for affected women. However, there is generally poor understanding of its etiology. Varying expert-based diagnostic criteria utilize some combination of oligo-ovulation, hyperandrogenism, and the presence of polycystic ovaries. Criteria that require hyperandrogenism tend to identify a more severe reproductive and metabolic phenotype. The phenotype can vary by race and ethnicity, is difficult to define in the perimenarchal and perimenopausal period, and is exacerbated by obesity. The pathophysiology involves abnormal gonadotropin secretion from a reduced hypothalamic feedback response to circulating sex steroids, altered ovarian morphology and functional changes, and disordered insulin action in a variety of target tissues. PCOS clusters in families and both female and male relatives can show stigmata of the syndrome, including metabolic abnormalities. Genome-wide association studies have identified a number of candidate regions, although their role in contributing to PCOS is still largely unknown. PMID:26426951

  5. Molecular epidemiology and genetic diversity of Entamoeba species in a chelonian collection.

    PubMed

    García, Gabriela; Ramos, Fernando; Pérez, Rodrigo Gutiérrez; Yañez, Jorge; Estrada, Mónica Salmerón; Mendoza, Lilian Hernández; Martinez-Hernandez, Fernando; Gaytán, Paul

    2014-02-01

    Veterinary medicine has focused recently on reptiles, due to the existence of captive collections in zoos and an increase in the acquisition of reptiles as pets. The protozoan parasite, Entamoeba can cause amoebiasis in various animal species and humans. Although amoebiasis disease is remarkably rare in most species of chelonians and crocodiles, these species may serve as Entamoeba species carriers that transmit parasites to susceptible reptile species, such as snakes and lizards, which can become sick and die. In this study, we identified the Entamoeba species in a population of healthy (disease-free) chelonians, and evaluated their diversity through the amplification and sequencing of a small subunit rDNA region. Using this procedure, three Entamoeba species were identified: Entamoeba invadens in 4.76 % of chelonians, Entamoeba moshkovskii in 3.96 % and Entamoeba terrapinae in 50 %. We did not detect mixed Entamoeba infections. Comparative analysis of the amplified region allowed us to determine the intra-species variations. The E. invadens and E. moshkovskii strains isolated in this study did not exhibit marked differences with respect to the sequences reported in GenBank. The analysis of the E. terrapinae isolates revealed three different subgroups (A, B and C). Although subgroups A and C were very similar, subgroup B showed a relatively marked difference with respect to subgroups A and C (Fst = 0.984 and Fst = 1.000, respectively; 10-14 % nucleotide variation, as determined by blast) and with respect to the sequences reported in GenBank. These results suggested that E. terrapinae subgroup B may be either in a process of speciation or belong to a different lineage. However, additional research is necessary to support this statement conclusively.

  6. Molecular epidemiology and genetic diversity of Entamoeba species in a chelonian collection.

    PubMed

    García, Gabriela; Ramos, Fernando; Pérez, Rodrigo Gutiérrez; Yañez, Jorge; Estrada, Mónica Salmerón; Mendoza, Lilian Hernández; Martinez-Hernandez, Fernando; Gaytán, Paul

    2014-02-01

    Veterinary medicine has focused recently on reptiles, due to the existence of captive collections in zoos and an increase in the acquisition of reptiles as pets. The protozoan parasite, Entamoeba can cause amoebiasis in various animal species and humans. Although amoebiasis disease is remarkably rare in most species of chelonians and crocodiles, these species may serve as Entamoeba species carriers that transmit parasites to susceptible reptile species, such as snakes and lizards, which can become sick and die. In this study, we identified the Entamoeba species in a population of healthy (disease-free) chelonians, and evaluated their diversity through the amplification and sequencing of a small subunit rDNA region. Using this procedure, three Entamoeba species were identified: Entamoeba invadens in 4.76 % of chelonians, Entamoeba moshkovskii in 3.96 % and Entamoeba terrapinae in 50 %. We did not detect mixed Entamoeba infections. Comparative analysis of the amplified region allowed us to determine the intra-species variations. The E. invadens and E. moshkovskii strains isolated in this study did not exhibit marked differences with respect to the sequences reported in GenBank. The analysis of the E. terrapinae isolates revealed three different subgroups (A, B and C). Although subgroups A and C were very similar, subgroup B showed a relatively marked difference with respect to subgroups A and C (Fst = 0.984 and Fst = 1.000, respectively; 10-14 % nucleotide variation, as determined by blast) and with respect to the sequences reported in GenBank. These results suggested that E. terrapinae subgroup B may be either in a process of speciation or belong to a different lineage. However, additional research is necessary to support this statement conclusively. PMID:24194557

  7. An Epidemiological and Diagnostic Study of Asperger Syndrome according to Four Sets of Diagnostic Criteria

    ERIC Educational Resources Information Center

    Mattila, Marja-Leena; Kielinen, Marko; Jussila, Katja; Linna, Sirkka-Liisa; Bloigu, Risto; Ebeling, Hanna; Moilanen, Irma

    2007-01-01

    Objective: This study evaluated the diagnostic process and prevalence rates of Asperger syndrome (AS) according to the DSM-IV, ICD-10, and criteria developed by Gillberg and Gillberg and by Szatmari and colleagues and clarified confusion about AS. Method: An epidemiological study of 5,484 eight-year-old children in Finland, 4,422 (80.6%) of whom…

  8. QMRA as a compliment to epidemiologic studies estimating bather risk at recreational beaches

    EPA Science Inventory

    The US EPA and WHO have set recreational water quality standards based on epidemiologic studies to protect human health at beaches. These studies have largely been limited to sewage-impacted sites and resources are unlikely to be available to assess the myriad of other impacted ...

  9. The Mystery of the Blue Death: A Case Study in Epidemiology and the History of Science

    ERIC Educational Resources Information Center

    Muench, Susan Bandoni

    2009-01-01

    This case study introduces students to John Snow, considered to be one of the founders of both epidemiology and anesthesiology, and a remarkable figure in the history of science. Although historical case studies are often less popular with students than contemporary issues (Herreid 1998), a number of aspects of this case make it attractive to…

  10. [Development of an epidemiological study in a polluted site: the unexpected contribution of sociological and medico-legal approaches].

    PubMed

    Pasetto, Roberto; Saitta, Pietro; Bracci, Carlo

    2008-01-01

    The article discusses the evolution of an occupational cohort study carried out in a polluted site. The authors highlight the need to define goals for the epidemiological characterization of polluted sites: a) retrospective health impact assessment, b) contribution to the definition of priorities for remediation activities, c) definition of epidemiological surveillance programs. They also advocate for an interdisciplinary approach to relate epidemiology to other branches of knowledge, especially qualitative sociology. Qualitative studies can be carried out both ex ante, prior to the epidemiological investigation, and ex post, to verify limits of the analysis itself. Useful and unintended elements for the epidemiological investigation are likely to emerge in the course of a study. During the process of epidemiological characterization, the outputs of each investigation should be considered as indices (or pointers). Indications for further research, operative decisions, public communication, should result from the collected indices as a whole.

  11. Molecular epidemiology and genetic linkage of macrolide and aminoglycoside resistance in Staphylococcus intermedius of canine origin.

    PubMed

    Boerlin, P; Burnens, A P; Frey, J; Kuhnert, P; Nicolet, J

    2001-03-20

    A collection of 77 Staphylococcus intermedius isolates from dogs and cats in Switzerland was examined for resistance to erythromycin. Resistance profiles for 14 additional antibiotics were compared between erythromycin-resistant and susceptible isolates. A resistance prevalence of 27% for erythromycin was observed in the population under study. Complete correlation between resistance to erythromycin, and to spiramycin, streptomycin, and neomycin was observed. The erythromycin-resistant isolates all had a reduced susceptibility to clindamycin when compared to the erythromycin-susceptible isolates. Both constitutive and inducible resistance phenotypes were observed for clindamycin. Ribotyping showed that macrolide-aminoglycoside resistance was randomly distributed among unrelated strains. This suggests that this particular resistance profile is not related to a single bacterial clone but to the horizontal transfer of resistance gene clusters in S. intermedius populations. The erythromycin-resistant isolates were all carrying erm(B), but not erm(A), erm(C), or msr(A). The erm(B) gene was physically linked to Tn5405-like elements known as resistance determinants for streptomycin, streptothricin, neomycin and kanamycin. Analysis of the region flanking erm(B) showed the presence of two different groups of erm(B)-Tn5405-like elements in the S. intermedius population examined and of elements found in Gram-positive species other than staphylococci. This strongly suggests that erm(B) or the whole erm(B)-Tn5405-like elements in S. intermedius originate from other bacterial species, possibly from enterococci. PMID:11230937

  12. Genetic epidemiology and pathology of raccoon-derived Sarcoptes mites from urban areas of Germany.

    PubMed

    Rentería-Solís, Z; Min, A M; Alasaad, S; Müller, K; Michler, F-U; Schmäschke, R; Wittstatt, U; Rossi, L; Wibbelt, G

    2014-08-01

    The raccoon, Procyon lotor (Carnivora: Procyonidae), is an invasive species that is spreading throughout Europe, in which Germany represents its core area. Here, raccoons mostly live in rural regions, but some urban populations are already established, such as in the city of Kassel, or are starting to build up, such as in Berlin. The objective of this study was to investigate Sarcoptes (Sarcoptiformes: Sarcoptidae) infections in racoons in these two urban areas and to identify the putative origin of the parasite. Parasite morphology, and gross and histopathological examinations of diseased skin tissue were consistent with Sarcoptes scabiei infection. Using nine microsatellite markers, we genotyped individual mites from five raccoons and compared them with Sarcoptes mites derived from fox, wild boar and Northern chamois, originating from Italy and Switzerland. The raccoon-derived mites clustered together with the fox samples and were clearly differentiated from those of the wild boar and chamois samples, which suggests a fox origin for the raccoon mange infection. These results are evidence of the cross-transmission of S. scabiei among wild carnivores. Although our results cannot elucidate whether raccoons became infected by frequent interaction with endemically or epidemically infected foxes or whether these cases resulted from occasional contacts among these animal species, they do nevertheless show that pathogens can be shared among urban populations of native and invasive carnivores.

  13. Molecular epidemiology and genetic linkage of macrolide and aminoglycoside resistance in Staphylococcus intermedius of canine origin.

    PubMed

    Boerlin, P; Burnens, A P; Frey, J; Kuhnert, P; Nicolet, J

    2001-03-20

    A collection of 77 Staphylococcus intermedius isolates from dogs and cats in Switzerland was examined for resistance to erythromycin. Resistance profiles for 14 additional antibiotics were compared between erythromycin-resistant and susceptible isolates. A resistance prevalence of 27% for erythromycin was observed in the population under study. Complete correlation between resistance to erythromycin, and to spiramycin, streptomycin, and neomycin was observed. The erythromycin-resistant isolates all had a reduced susceptibility to clindamycin when compared to the erythromycin-susceptible isolates. Both constitutive and inducible resistance phenotypes were observed for clindamycin. Ribotyping showed that macrolide-aminoglycoside resistance was randomly distributed among unrelated strains. This suggests that this particular resistance profile is not related to a single bacterial clone but to the horizontal transfer of resistance gene clusters in S. intermedius populations. The erythromycin-resistant isolates were all carrying erm(B), but not erm(A), erm(C), or msr(A). The erm(B) gene was physically linked to Tn5405-like elements known as resistance determinants for streptomycin, streptothricin, neomycin and kanamycin. Analysis of the region flanking erm(B) showed the presence of two different groups of erm(B)-Tn5405-like elements in the S. intermedius population examined and of elements found in Gram-positive species other than staphylococci. This strongly suggests that erm(B) or the whole erm(B)-Tn5405-like elements in S. intermedius originate from other bacterial species, possibly from enterococci.

  14. Genetic epidemiology and pathology of raccoon-derived Sarcoptes mites from urban areas of Germany.

    PubMed

    Rentería-Solís, Z; Min, A M; Alasaad, S; Müller, K; Michler, F-U; Schmäschke, R; Wittstatt, U; Rossi, L; Wibbelt, G

    2014-08-01

    The raccoon, Procyon lotor (Carnivora: Procyonidae), is an invasive species that is spreading throughout Europe, in which Germany represents its core area. Here, raccoons mostly live in rural regions, but some urban populations are already established, such as in the city of Kassel, or are starting to build up, such as in Berlin. The objective of this study was to investigate Sarcoptes (Sarcoptiformes: Sarcoptidae) infections in racoons in these two urban areas and to identify the putative origin of the parasite. Parasite morphology, and gross and histopathological examinations of diseased skin tissue were consistent with Sarcoptes scabiei infection. Using nine microsatellite markers, we genotyped individual mites from five raccoons and compared them with Sarcoptes mites derived from fox, wild boar and Northern chamois, originating from Italy and Switzerland. The raccoon-derived mites clustered together with the fox samples and were clearly differentiated from those of the wild boar and chamois samples, which suggests a fox origin for the raccoon mange infection. These results are evidence of the cross-transmission of S. scabiei among wild carnivores. Although our results cannot elucidate whether raccoons became infected by frequent interaction with endemically or epidemically infected foxes or whether these cases resulted from occasional contacts among these animal species, they do nevertheless show that pathogens can be shared among urban populations of native and invasive carnivores. PMID:25171612

  15. Molecular Epidemiology of Malaria

    PubMed Central

    Conway, David J.

    2007-01-01

    Malaria persists as an undiminished global problem, but the resources available to address it have increased. Many tools for understanding its biology and epidemiology are well developed, with a particular richness of comparative genome sequences. Targeted genetic manipulation is now effectively combined with in vitro culture assays on the most important human parasite, Plasmodium falciparum, and with in vivo analysis of rodent and monkey malaria parasites in their laboratory hosts. Studies of the epidemiology, prevention, and treatment of human malaria have already been influenced by the availability of molecular methods, and analyses of parasite polymorphisms have long had useful and highly informative applications. However, the molecular epidemiology of malaria is currently undergoing its most substantial revolution as a result of the genomic information and technologies that are available in well-resourced centers. It is a challenge for research agendas to face the real needs presented by a disease that largely exists in extremely resource-poor settings, but it is one that there appears to be an increased willingness to undertake. To this end, developments in the molecular epidemiology of malaria are reviewed here, emphasizing aspects that may be current and future priorities. PMID:17223628

  16. Melanoma Epidemiology and Prevention.

    PubMed

    Berwick, Marianne; Buller, David B; Cust, Anne; Gallagher, Richard; Lee, Tim K; Meyskens, Frank; Pandey, Shaily; Thomas, Nancy E; Veierød, Marit B; Ward, Sarah

    2016-01-01

    The epidemiology of melanoma is complex, and individual risk depends on sun exposure, host factors, and genetic factors, and in their interactions as well. Sun exposure can be classified as intermittent, chronic, or cumulative (overall) exposure, and each appears to have a different effect on type of melanoma. Other environmental factors, such as chemical exposures-either through occupation, atmosphere, or food-may increase risk for melanoma, and this area warrants further study. Host factors that are well known to be important are the numbers and types of nevi and the skin phenotype. Genetic factors are classified as high-penetrant genes, moderate-risk genes, or low-risk genetic polymorphisms. Subtypes of tumors, such as BRAF-mutated tumors, have different risk factors as well as different therapies. Prevention of melanoma has been attempted using various strategies in specific subpopulations, but to date optimal interventions to reduce incidence have not emerged. PMID:26601858

  17. Epidemiology, pathology, and genetic analysis of a canine distemper epidemic in Namibia.

    PubMed

    Gowtage-Sequeira, Sonya; Banyard, Ashley C; Barrett, Tom; Buczkowski, Hubert; Funk, Stephan M; Cleaveland, Sarah

    2009-10-01

    Severe population declines have resulted from the spillover of canine distemper virus (CDV) into susceptible wildlife, with both domestic and wild canids being involved in the maintenance and transmission of the virus. This study (March 2001 to October 2003) collated case data, serologic, pathologic, and molecular data to describe the spillover of CDV from domestic dogs (Canis familiaris) to black-backed jackals (Canis mesomelas) during an epidemic on the Namibian coast. Antibody prevalence in jackals peaked at 74.1%, and the clinical signs and histopathologic observations closely resembled those observed in domestic dog cases. Viral RNA was isolated from the brain of a domestic dog from the outbreak area. Sequence data from the phosphoprotein (P) gene and the hemagglutinin (H) genes were used for phylogenetic analyses. The P gene sequence from the domestic dog shared 98% identity with the sequence data available for other CDV isolates of African carnivores. For the H gene, the two sequences available from the outbreak that decimated the lion population in Tanzania in 1994 were the closest match with the Namibian sample, being 94% identical across 1,122 base pairs (bp). Phylogenetic analyses based on this region clustered the Namibian sample with the CDV that is within the morbilliviruses. This is the first description of an epidemic involving black-backed jackals in Namibia, demonstrating that this species has the capacity for rapid and large-scale dissemination of CDV. This work highlights the threat posed to endangered wildlife in Namibia by the spillover of CDV from domestic dog populations. Very few sequence data are currently available for CDV isolates from African carnivores, and this work provides the first sequence data from a Namibian CDV isolate. PMID:19901377

  18. Epidemiology and genetic diversity of criniviruses associated with tomato yellows disease in Greece.

    PubMed

    Orfanidou, C G; Dimitriou, C; Papayiannis, L C; Maliogka, V I; Katis, N I

    2014-06-24

    Tomato chlorosis virus (ToCV) and Tomato infectious chlorosis virus (TICV) are two whitefly transmitted viruses which are classified in the genus Crinivirus of the family Closteroviridae. Both induce similar yellowing symptoms in tomato and are responsible for severe economic losses. ToCV is transmitted by Bemisia tabaci Gennadious, Trialeurodes vaporariorum Westwood and Trialeurodes abutilonea Haldeman, whereas TICV is transmitted only by T. vaporariorum. An extensive study was conducted during 2009-2012 in order to identify the virus species involved in tomato yellowing disease in Greece. Samples from tomato, other crops and weeds belonging to 44 species from 26 families were collected and analyzed using molecular methods. In addition, adult whiteflies were collected and analyzed using morphological characters and DNA markers. Results showed that TICV prevailed in tomato crops (62.5%), while ToCV incidence was lower (20.5%) and confined in southern Greece. ToCV was also detected in lettuce plants showing mild yellowing symptoms for the first time in Greece. Approximately 13% of the tested weeds were found to be infected, with TICV being the predominant virus with an incidence of 10.8%, whereas ToCV was detected only in 2.2% of the analyzed samples. These results indicate that the host range of TICV and ToCV in Greece is far more extensive than previously believed. T. vaporariorum was the most widespread whitefly species in Greece (80%), followed by B. tabaci (biotypes B and Q) (20%). Sequence analysis of the CP and CPm genes from Greek tomato and weed isolates of ToCV and TICV showed that even though both viruses have very wide host ranges their populations show very low molecular divergence.

  19. Epidemiology and genetic diversity of criniviruses associated with tomato yellows disease in Greece.

    PubMed

    Orfanidou, C G; Dimitriou, C; Papayiannis, L C; Maliogka, V I; Katis, N I

    2014-06-24

    Tomato chlorosis virus (ToCV) and Tomato infectious chlorosis virus (TICV) are two whitefly transmitted viruses which are classified in the genus Crinivirus of the family Closteroviridae. Both induce similar yellowing symptoms in tomato and are responsible for severe economic losses. ToCV is transmitted by Bemisia tabaci Gennadious, Trialeurodes vaporariorum Westwood and Trialeurodes abutilonea Haldeman, whereas TICV is transmitted only by T. vaporariorum. An extensive study was conducted during 2009-2012 in order to identify the virus species involved in tomato yellowing disease in Greece. Samples from tomato, other crops and weeds belonging to 44 species from 26 families were collected and analyzed using molecular methods. In addition, adult whiteflies were collected and analyzed using morphological characters and DNA markers. Results showed that TICV prevailed in tomato crops (62.5%), while ToCV incidence was lower (20.5%) and confined in southern Greece. ToCV was also detected in lettuce plants showing mild yellowing symptoms for the first time in Greece. Approximately 13% of the tested weeds were found to be infected, with TICV being the predominant virus with an incidence of 10.8%, whereas ToCV was detected only in 2.2% of the analyzed samples. These results indicate that the host range of TICV and ToCV in Greece is far more extensive than previously believed. T. vaporariorum was the most widespread whitefly species in Greece (80%), followed by B. tabaci (biotypes B and Q) (20%). Sequence analysis of the CP and CPm genes from Greek tomato and weed isolates of ToCV and TICV showed that even though both viruses have very wide host ranges their populations show very low molecular divergence. PMID:24370865

  20. Epidemiology, pathology, and genetic analysis of a canine distemper epidemic in Namibia.

    PubMed

    Gowtage-Sequeira, Sonya; Banyard, Ashley C; Barrett, Tom; Buczkowski, Hubert; Funk, Stephan M; Cleaveland, Sarah

    2009-10-01

    Severe population declines have resulted from the spillover of canine distemper virus (CDV) into susceptible wildlife, with both domestic and wild canids being involved in the maintenance and transmission of the virus. This study (March 2001 to October 2003) collated case data, serologic, pathologic, and molecular data to describe the spillover of CDV from domestic dogs (Canis familiaris) to black-backed jackals (Canis mesomelas) during an epidemic on the Namibian coast. Antibody prevalence in jackals peaked at 74.1%, and the clinical signs and histopathologic observations closely resembled those observed in domestic dog cases. Viral RNA was isolated from the brain of a domestic dog from the outbreak area. Sequence data from the phosphoprotein (P) gene and the hemagglutinin (H) genes were used for phylogenetic analyses. The P gene sequence from the domestic dog shared 98% identity with the sequence data available for other CDV isolates of African carnivores. For the H gene, the two sequences available from the outbreak that decimated the lion population in Tanzania in 1994 were the closest match with the Namibian sample, being 94% identical across 1,122 base pairs (bp). Phylogenetic analyses based on this region clustered the Namibian sample with the CDV that is within the morbilliviruses. This is the first description of an epidemic involving black-backed jackals in Namibia, demonstrating that this species has the capacity for rapid and large-scale dissemination of CDV. This work highlights the threat posed to endangered wildlife in Namibia by the spillover of CDV from domestic dog populations. Very few sequence data are currently available for CDV isolates from African carnivores, and this work provides the first sequence data from a Namibian CDV isolate.

  1. Molecular and epidemiological studies of Porcine rubulavirus infection – an overview

    PubMed Central

    Cuevas-Romero, Julieta Sandra; Blomström, Anne-Lie; Berg, Mikael

    2015-01-01

    Porcine rubulavirus-La Piedad-Michoacan-Mexico virus (PorPV-LPMV) was identified as the causative agent of a viral disease that emerged spontaneously in Mexican swine in the 1980s. Since the report of the initial outbreak of the disease, only one full-length genome from a strain isolated in 1984 (PorPV-LPMV/1984) has been sequenced; sequence data are scarce from other isolates. The genetic variation of this virus that has spread throughout the main endemic region of Mexico is almost a complete mystery. The development of molecular techniques for improved diagnostics and to investigate the persistence, molecular epidemiology, and the possible reservoirs of PorPV are needed. Together, this will provide greater knowledge regarding the molecular genetic changes and useful data to establish new strategies in the control of this virus in Mexico. PMID:26584829

  2. A study on the life-cycle and epidemiology of Pseudanoplocephala crawfordi Baylis, 1927.

    PubMed

    Jiang, T J; Jin, Z H; Wu, H; Cui, C Q

    1990-03-01

    A study of the life-cycle and epidemiology of Pseudanoplocephala crawfordi Baylis, 1927 is reported. Intermediate hosts are Tenebrio obscurus, T. molitor, Carpophilus dimidiatus and Tribolium castaneum. The first three species are new host records. Development in the intermediate host takes 1-1.5 months. The completion of the life-cycle takes 2-2.5 months. Surveys of intermediate hosts, pigs, humans and rats were carried out. In Rattus norvegicus, the prevalence was as high as 22%. Epidemiological factors and suggestions for control measures are discussed.

  3. Spanish multicenter study of the epidemiology and mechanisms of amoxicillin-clavulanate resistance in Escherichia coli.

    PubMed

    Ortega, Adriana; Oteo, Jesús; Aranzamendi-Zaldumbide, Maitane; Bartolomé, Rosa M; Bou, Germán; Cercenado, Emilia; Conejo, M Carmen; González-López, Juan José; Marín, Mercedes; Martínez-Martínez, Luis; Merino, María; Navarro, Ferran; Oliver, Antonio; Pascual, Alvaro; Rivera, Alba; Rodríguez-Baño, Jesús; Weber, Irene; Aracil, Belén; Campos, José

    2012-07-01

    We conducted a prospective multicenter study in Spain to characterize the mechanisms of resistance to amoxicillin-clavulanate (AMC) in Escherichia coli. Up to 44 AMC-resistant E. coli isolates (MIC ≥ 32/16 μg/ml) were collected at each of the seven participant hospitals. Resistance mechanisms were characterized by PCR and sequencing. Molecular epidemiology was studied by pulsed-field gel electrophoresis (PFGE) and by multilocus sequence typing. Overall AMC resistance was 9.3%. The resistance mechanisms detected in the 257 AMC-resistant isolates were OXA-1 production (26.1%), hyperproduction of penicillinase (22.6%), production of plasmidic AmpC (19.5%), hyperproduction of chromosomic AmpC (18.3%), and production of inhibitor-resistant TEM (IRT) (17.5%). The IRTs identified were TEM-40 (33.3%), TEM-30 (28.9%), TEM-33 (11.1%), TEM-32 (4.4%), TEM-34 (4.4%), TEM-35 (2.2%), TEM-54 (2.2%), TEM-76 (2.2%), TEM-79 (2.2%), and the new TEM-185 (8.8%). By PFGE, a high degree of genetic diversity was observed although two well-defined clusters were detected in the OXA-1-producing isolates: the C1 cluster consisting of 19 phylogroup A/sequence type 88 [ST88] isolates and the C2 cluster consisting of 19 phylogroup B2/ST131 isolates (16 of them producing CTX-M-15). Each of the clusters was detected in six different hospitals. In total, 21.8% of the isolates were serotype O25b/phylogroup B2 (O25b/B2). AMC resistance in E. coli is widespread in Spain at the hospital and community levels. A high prevalence of OXA-1 was found. Although resistant isolates were genetically diverse, clonality was linked to OXA-1-producing isolates of the STs 88 and 131. Dissemination of IRTs was frequent, and the epidemic O25b/B2/ST131 clone carried many different mechanisms of AMC resistance. PMID:22491692

  4. An epidemiological approach to study fatigue in the working population: the Maastricht Cohort Study

    PubMed Central

    Kant, I.; Bultmann, U; Schroer, K; Beurskens, A; van Amelsvoort, L G P M; Swaen, G

    2003-01-01

    In 1998, a large scale prospective cohort study of prolonged fatigue in the working population was started in the Netherlands. The ultimate goal of this Maastricht Cohort Study was to identify risk factors involved in the aetiology and natural course of prolonged fatigue in the working population and to develop preventive measures and treatments that can be used in occupational health settings. In this paper, a conceptual model for epidemiological research on prolonged fatigue is presented. This model is the basis for the Maastricht Cohort Study. Alongside the model and design, the characteristics of the study population, the prevalence and one year cumulative incidence of prolonged fatigue, as well as its relation with secondary health outcomes (psychological distress, need for recovery, and burnout) are presented. Furthermore, model, design, and the presented results are discussed. PMID:12782745

  5. Influence of DNA extraction methods on relative telomere length measurements and its impact on epidemiological studies

    PubMed Central

    Raschenberger, Julia; Lamina, Claudia; Haun, Margot; Kollerits, Barbara; Coassin, Stefan; Boes, Eva; Kedenko, Ludmilla; Köttgen, Anna; Kronenberg, Florian

    2016-01-01

    Measurement of telomere length is widely used in epidemiologic studies. Insufficient standardization of the measurements processes has, however, complicated the comparison of results between studies. We aimed to investigate whether DNA extraction methods have an influence on measured values of relative telomere length (RTL) and whether this has consequences for epidemiological studies. We performed four experiments with RTL measurement in quadruplicate by qPCR using DNA extracted with different methods: 1) a standardized validation experiment including three extraction methods (magnetic-particle-method EZ1, salting-out-method INV, phenol-chloroform-isoamyl-alcohol PCI) each in the same 20 samples demonstrated pronounced differences in RTL with lowest values with EZ1 followed by INV and PCI-isolated DNA; 2) a comparison of 307 samples from an epidemiological study showing EZ1-measurements 40% lower than INV-measurements; 3) a matching-approach of two similar non-diseased control groups including 143 pairs of subjects revealed significantly shorter RTL in EZ1 than INV-extracted DNA (0.844 ± 0.157 vs. 1.357 ± 0.242); 4) an association analysis of RTL with prevalent cardiovascular disease detected a stronger association with INV than with EZ1-extracted DNA. In summary, DNA extraction methods have a pronounced influence on the measured RTL-values. This might result in spurious or lost associations in epidemiological studies under certain circumstances. PMID:27138987

  6. Influence of DNA extraction methods on relative telomere length measurements and its impact on epidemiological studies.

    PubMed

    Raschenberger, Julia; Lamina, Claudia; Haun, Margot; Kollerits, Barbara; Coassin, Stefan; Boes, Eva; Kedenko, Ludmilla; Köttgen, Anna; Kronenberg, Florian

    2016-01-01

    Measurement of telomere length is widely used in epidemiologic studies. Insufficient standardization of the measurements processes has, however, complicated the comparison of results between studies. We aimed to investigate whether DNA extraction methods have an influence on measured values of relative telomere length (RTL) and whether this has consequences for epidemiological studies. We performed four experiments with RTL measurement in quadruplicate by qPCR using DNA extracted with different methods: 1) a standardized validation experiment including three extraction methods (magnetic-particle-method EZ1, salting-out-method INV, phenol-chloroform-isoamyl-alcohol PCI) each in the same 20 samples demonstrated pronounced differences in RTL with lowest values with EZ1 followed by INV and PCI-isolated DNA; 2) a comparison of 307 samples from an epidemiological study showing EZ1-measurements 40% lower than INV-measurements; 3) a matching-approach of two similar non-diseased control groups including 143 pairs of subjects revealed significantly shorter RTL in EZ1 than INV-extracted DNA (0.844 ± 0.157 vs. 1.357 ± 0.242); 4) an association analysis of RTL with prevalent cardiovascular disease detected a stronger association with INV than with EZ1-extracted DNA. In summary, DNA extraction methods have a pronounced influence on the measured RTL-values. This might result in spurious or lost associations in epidemiological studies under certain circumstances. PMID:27138987

  7. Epidemiology and genetic characterization of BVDV, BHV-1, BHV-4, BHV-5 and Brucella spp. infections in cattle in Turkey.

    PubMed

    Aslan, Muhammet Eren; Azkur, Ahmet Kursat; Gazyagci, Serkal

    2015-11-01

    The aim of the study was to determine the epidemiological data of bovine viral diarrhea virus (BVDV), bovine herpesvirus-1 (BHV-1), bovine herpesvirus-4 (BHV-4), bovine herpesvirus-5 (BHV-5) and Brucella-associated cattle that were previously reported to have abortion and infertility problems in Ankara, Corum, Kirikkale and Yozgat provinces, Turkey. Whole blood and sera samples were obtained from 656 cattle, and antibodies against Brucella spp. were detected in 45 (6.86%) and 41 (6.25%) animals by Rose Bengal plate and serum tube agglutination tests, respectively. The seropositivity rates against BVDV, BHV-1 and BHV-4 were 70.89%, 41.3% and 28.78%, respectively. RT-PCR and PCR were performed to detect RNA and DNA viruses in blood samples, respectively. The BVDV 5'-untranslated region and BHV-1 gB gene detected in this study were phylogenetically analyzed. The BVDV strains analyzed in this study were closely related to those previously reported from Turkey. The nucleotide sequence from the BHV-1 strain detected in this study is the first nucleotide sequence of BHV-1 circulating in this area of Turkey deposited in the GenBank. The presence of Brucella spp. and prevalence of BHV-1, BHV-4 and BVDV in cattle should be further investigated throughout these regions.

  8. Epidemiological studies of oats consumption and risk of cancer and overall mortality.

    PubMed

    Boffetta, Paolo; Thies, Frank; Kris-Etherton, Penny

    2014-10-01

    A review of epidemiological studies on the intake of oats and oat-based products and its effect on the risk of chronic disease and deaths was performed. Seven studies were identified of cancer risk (two each on prostate and colorectal cancer, and one each on pancreatic, breast and endometrial cancer), and one study on overall mortality. With the exception of a case-control study of pancreatic cancer, all studies were of cohort design: five studies were based on a single cohort from Denmark. The results of most cohort studies suggest a weak protective effect of a high intake of oats on cancer risk (relative risks in the order of 0·9). Potential limitations of the studies are dietary exposure misclassification, low statistical power because of limited exposure contrast and residual confounding. Despite the evidence from experimental and mechanistic studies of a protective effect of oats intake on CVD and diabetes, no epidemiological studies have been conducted on these conditions.

  9. Epidemiology of colorectal cancer

    PubMed Central

    Marley, Andrew R; Nan, Hongmei

    2016-01-01

    Colorectal cancer is currently the third deadliest cancer in the United States and will claim an estimated 49,190 U.S. lives in 2016. The purpose of this review is to summarize our current understanding of this disease, based on nationally published statistics and information presented in peer-reviewed journal articles. Specifically, this review will cover the following topics: descriptive epidemiology (including time and disease trends both in the United States and abroad), risk factors (environmental, genetic, and gene-environment interactions), screening, prevention and control, and treatment. Landmark discoveries in colorectal cancer risk factor research will also be presented. Based on the information reviewed for this report, we suggest that future U.S. public health efforts aim to increase colorectal cancer screening among African American communities, and that future worldwide colorectal cancer epidemiology studies should focus on researching nutrient-gene interactions towards the goal of improving personalized treatment and prevention strategies. PMID:27766137

  10. Multiple imputation in veterinary epidemiological studies: a case study and simulation.

    PubMed

    Dohoo, Ian R; Nielsen, Christel R; Emanuelson, Ulf

    2016-07-01

    The problem of missing data occurs frequently in veterinary epidemiological studies. Most studies use a complete case (CC) analysis which excludes all observations for which any relevant variable have missing values. Alternative approaches (most notably multiple imputation (MI)) which avoid the exclusion of observations with missing values are now widely available but have been used very little in veterinary epidemiology. This paper uses a case study based on research into dairy producers' attitudes toward mastitis control procedures, combined with two simulation studies to evaluate the use of MI and compare results with a CC analysis. MI analysis of the original data produced results which had relatively minor differences from the CC analysis. However, most of the missing data in the original data set were in the dependent variable and a subsequent simulation study based on the observed missing data pattern and 1000 simulations showed that an MI analysis would not be expected to offer any advantages over a CC analysis in this situation. This was true regardless of the missing data mechanism (MCAR - missing completely at random, MAR - missing at random, or NMAR - not missing at random) underlying the missing values. Surprisingly, recent textbooks dealing with MI make little reference to this limitation of MI for dealing with missing values in the dependent variable. An additional simulation study (1000 runs for each of the three missing data mechanisms) compared MI and CC analyses for data in which varying levels (n=7) of missing data were created in predictor variables. This study showed that MI analyses generally produced results that were less biased on average, were more precise (smaller SEs), were more consistent (less variability between simulation runs) and consequently were more likely to produce estimates that were close to the "truth" (results obtained from a data set with no missing values). While the benefit of MI varied with the mechanism used to

  11. [Peculiarities of neoplastic epidemiologic studies in children residing near nickel producing facilities].

    PubMed

    Chashchin, V P; Bykov, V P

    2004-01-01

    Studying risk factors of malignancies in children who reside near nickel metallurgic enterprise covers creation of a register for long-term epidemiologic monitoring. The article presents possible ways to obtain reliable information from various sources, deals with their positive and negative aspects for electronic database.

  12. [Prevalence of dentition defects among pre-school children of Tver region according to epidemiological study].

    PubMed

    Beliaev, V V; Bobrov, D V; Chumakov, A N; Al'-Zrir, O; El'-Aĭdi, M A

    2015-01-01

    Epidemiological dental study of 724 pre-school children in Tver region revealed high prevalence of dentition defects due to premature removal of temporary molars. Dependence of pediatric population need for prosthetic dentistry from regional dental care system staff competence is shown. The date proved the need for standard correction of orthodontists number and broad application of pediatric prosthetics in daily practice.

  13. Putting Life into Computer-Based Training: The Creation of an Epidemiologic Case Study.

    ERIC Educational Resources Information Center

    Gathany, Nancy C.; Stehr-Green, Jeanette K.

    1994-01-01

    Describes the design of "Pharyngitis in Louisiana," a computer-based epidemiologic case study that was created to teach students how to conduct disease outbreak investigations. Topics discussed include realistic content portrayals; graphics; interactive teaching methods; interaction between the instructional designer and the medical expert; and…

  14. An Epidemiological Study of Number Processing and Mental Calculation in Greek Schoolchildren

    ERIC Educational Resources Information Center

    Koumoula, Anastasia; Tsironi, Vanda; Stamouli, Victoria; Bardani, Irini; Stavroula, Siapati; Graham, Annik; Kafantaris, Ignatios; Charalambidou, Irini; Dellatolas, Georges; von Aster, Michael

    2004-01-01

    The aim of this study was to validate and standardize an instrument for the diagnosis of developmental dyscalculia (mathematics disorder) in a Greek population and to obtain relevant epidemiological data. We used the "Neuropsychological Test Battery for Number Processing and Calculation in Children" (NUCALC) in a community sample of 240 students…

  15. BREATH MEASUREMENT OF TOTAL BODY BURDEN OF JP-8 JET FUEL FOR EPIDEMIOLOGICAL STUDY

    EPA Science Inventory

    A complex epidemiological investigation of the effects of acute exposure to JP-8 jet fuel in the U.S. Air Force was performed through the study of about 350 human subjects across six Air Force bases. The focus was on fuels system maintenance personnel as the "exposed"...

  16. Validating the Center for Epidemiological Studies Depression Scale for Children in Rwanda

    ERIC Educational Resources Information Center

    Betancourt, Theresa; Scorza, Pamela; Meyers-Ohki, Sarah; Mushashi, Christina; Kayiteshonga, Yvonne; Binagwaho, Agnes; Stulac, Sara; Beardslee, William R.

    2012-01-01

    Objective: We assessed the validity of the Center for Epidemiological Studies Depression Scale for Children (CES-DC) as a screen for depression in Rwandan children and adolescents. Although the CES-DC is widely used for depression screening in high-income countries, its validity in low-income and culturally diverse settings, including sub-Saharan…

  17. Exposure prediction approaches used in air pollution epidemiology studies: Keyfindings and future recommendations

    EPA Science Inventory

    Many epidemiologic studies of the health effects of exposure to ambient air pollution use measurements from central-site monitors as their exposure estimate. However, measurements from central-site monitors may lack the spatial and temporal resolution required to capture exposure...

  18. Factorial and Discriminant Validity of the Center for Epidemiological Studies Depression (CES-D) Scale.

    ERIC Educational Resources Information Center

    Orme, John G.; And Others

    1986-01-01

    Examined the factorial and discriminant validity of the Center for Epidemiological Studies Depression (CES-D) scale for 116 parents participating in family support programs. Factorial validity was adequate, and results indicated a moderate correlation between the CES-D and self-esteem and state anxiety. However, a high correlation was obtained…

  19. "Development of Model-Based Air Pollution Exposure Metrics for use in Epidemiologic Studies"

    EPA Science Inventory

    Population-based epidemiological studies of air pollution have traditionally relied upon imperfect surrogates of personal exposures, such as area-wide ambient air pollution levels based on readily available concentrations from central monitoring sites. U.S. EPA in collaboration w...

  20. DEVELOPMENT OF MODEL-BASED AIR POLLUTION EXPOSURE METRICS FOR USE IN EPIDEMIOLOGIC STUDIES

    EPA Science Inventory

    Population-based epidemiological studies of air pollution have traditionally relied upon imperfect surrogates of personal exposures, such as area-wide ambient air pollution levels based on readily available concentrations from central monitoring sites. U.S. EPA in collaboration w...

  1. Multicentre study highlighting clinical relevance of new high-throughput methodologies in molecular epidemiology of Pneumocystis jirovecii pneumonia.

    PubMed

    Esteves, F; de Sousa, B; Calderón, E J; Huang, L; Badura, R; Maltez, F; Bassat, Q; de Armas, Y; Antunes, F; Matos, O

    2016-06-01

    Pneumocystis jirovecii causes severe interstitial pneumonia (PcP) in immunosuppressed patients. This multicentre study assessed the distribution frequencies of epidemiologically relevant genetic markers of P. jirovecii in different geographic populations from Portugal, the USA, Spain, Cuba and Mozambique, and the relationship between the molecular data and the geographical and clinical information, based on a multifactorial approach. The high-throughput typing strategy for P. jirovecii characterization consisted of DNA pooling using quantitative real-time PCR followed by multiplex-PCR/single base extension. The frequencies of relevant P. jirovecii single nucleotide polymorphisms (mt85, SOD110, SOD215, DHFR312, DHPS165 and DHPS171) encoded at four loci were estimated in ten DNA pooled samples representing a total of 182 individual samples. Putative multilocus genotypes of P. jirovecii were shown to be clustered due to geographic differences but were also dependent on clinical characteristics of the populations studied. The haplotype DHFR312T/SOD110C/SOD215T was associated with severe AIDS-related PcP and high P. jirovecii burdens. The frequencies of this genetic variant of P. jirovecii were significantly higher in patients with AIDS-related PcP from Portugal and the USA than in the colonized patients from Portugal, and Spain, and children infected with P. jirovecii from Cuba or Mozambique, highlighting the importance of this haplotype, apparently associated with the severity of the disease and specific clinical groups. Patients from the USA and Mozambique showed higher rates of DHPS mutants, which may suggest the circulation of P. jirovecii organisms potentially related with trimethoprim-sulfamethoxazole resistance in those geographical regions. This report assessed the worldwide distribution of P. jirovecii haplotypes and their epidemiological impact in distinct geographic and clinical populations.

  2. Multicentre study highlighting clinical relevance of new high-throughput methodologies in molecular epidemiology of Pneumocystis jirovecii pneumonia.

    PubMed

    Esteves, F; de Sousa, B; Calderón, E J; Huang, L; Badura, R; Maltez, F; Bassat, Q; de Armas, Y; Antunes, F; Matos, O

    2016-06-01

    Pneumocystis jirovecii causes severe interstitial pneumonia (PcP) in immunosuppressed patients. This multicentre study assessed the distribution frequencies of epidemiologically relevant genetic markers of P. jirovecii in different geographic populations from Portugal, the USA, Spain, Cuba and Mozambique, and the relationship between the molecular data and the geographical and clinical information, based on a multifactorial approach. The high-throughput typing strategy for P. jirovecii characterization consisted of DNA pooling using quantitative real-time PCR followed by multiplex-PCR/single base extension. The frequencies of relevant P. jirovecii single nucleotide polymorphisms (mt85, SOD110, SOD215, DHFR312, DHPS165 and DHPS171) encoded at four loci were estimated in ten DNA pooled samples representing a total of 182 individual samples. Putative multilocus genotypes of P. jirovecii were shown to be clustered due to geographic differences but were also dependent on clinical characteristics of the populations studied. The haplotype DHFR312T/SOD110C/SOD215T was associated with severe AIDS-related PcP and high P. jirovecii burdens. The frequencies of this genetic variant of P. jirovecii were significantly higher in patients with AIDS-related PcP from Portugal and the USA than in the colonized patients from Portugal, and Spain, and children infected with P. jirovecii from Cuba or Mozambique, highlighting the importance of this haplotype, apparently associated with the severity of the disease and specific clinical groups. Patients from the USA and Mozambique showed higher rates of DHPS mutants, which may suggest the circulation of P. jirovecii organisms potentially related with trimethoprim-sulfamethoxazole resistance in those geographical regions. This report assessed the worldwide distribution of P. jirovecii haplotypes and their epidemiological impact in distinct geographic and clinical populations. PMID:27021425

  3. Mapping epidemiology's past to inform its future: metaknowledge analysis of epidemiologic topics in leading journals, 1974-2013.

    PubMed

    Trinquart, Ludovic; Galea, Sandro

    2015-07-15

    An empiric perspective on what epidemiology has studied over time might inform discussions about future directions for the discipline. We aimed to identify the main areas of epidemiologic inquiry and determine how they evolved over time in 5 high-impact epidemiologic journals. We analyzed the titles and abstracts of 20,895 articles that were published between 1974 and 2013. In 5 time periods that reflected approximately equal numbers of articles, we identified the main topics by clustering terms based on co-occurrence. Infectious disease and cardiovascular disease epidemiology were the prevailing topics over the 5 periods. Cancer epidemiology was a major topic from 1974 to 2001 but disappeared thereafter. Nutritional epidemiology gained relative importance from 1974 to 2013. Environmental epidemiology appeared during 1996-2001 and continued to be important, whereas 2 clusters related to methodology and meta-analysis in genetics appeared during 2008-2013. Several areas of epidemiology, including injury or psychiatric epidemiology, did not make an appearance as major topics at any time. In an ancillary analysis of 6 high-impact general medicine journals, we found patterns of epidemiologic articles that were overall consistent with the findings in epidemiologic journals. This metaknowledge investigation allowed identification of the dominant topics in and conversely those that were absent from 5 major epidemiologic journals. We discuss implications for the field.

  4. Mapping epidemiology's past to inform its future: metaknowledge analysis of epidemiologic topics in leading journals, 1974-2013.

    PubMed

    Trinquart, Ludovic; Galea, Sandro

    2015-07-15

    An empiric perspective on what epidemiology has studied over time might inform discussions about future directions for the discipline. We aimed to identify the main areas of epidemiologic inquiry and determine how they evolved over time in 5 high-impact epidemiologic journals. We analyzed the titles and abstracts of 20,895 articles that were published between 1974 and 2013. In 5 time periods that reflected approximately equal numbers of articles, we identified the main topics by clustering terms based on co-occurrence. Infectious disease and cardiovascular disease epidemiology were the prevailing topics over the 5 periods. Cancer epidemiology was a major topic from 1974 to 2001 but disappeared thereafter. Nutritional epidemiology gained relative importance from 1974 to 2013. Environmental epidemiology appeared during 1996-2001 and continued to be important, whereas 2 clusters related to methodology and meta-analysis in genetics appeared during 2008-2013. Several areas of epidemiology, including injury or psychiatric epidemiology, did not make an appearance as major topics at any time. In an ancillary analysis of 6 high-impact general medicine journals, we found patterns of epidemiologic articles that were overall consistent with the findings in epidemiologic journals. This metaknowledge investigation allowed identification of the dominant topics in and conversely those that were absent from 5 major epidemiologic journals. We discuss implications for the field. PMID:25977517

  5. Triparental Families: A New Genetic-Epidemiological Design Applied to Drug Abuse, Alcohol Use Disorders, and Criminal Behavior in a Swedish National Sample

    PubMed Central

    Kendler, Kenneth S.; Ohlsson, Henrik; Sundquist, Jan; Sundquist, Kristina

    2015-01-01

    Objective The authors sought to clarify the sources of parent-offspring resemblance for drug abuse, alcohol use disorders, and criminal behavior, using a novel genetic-epidemiological design. Method Using national registries, the authors identified rates of drug abuse, alcohol use disorders, and criminal behavior in 41,360 Swedish individuals born between 1960 and 1990 and raised in triparental families comprising a biological mother who reared them, a “not-lived-with” biological father, and a stepfather. Results When each syndrome was examined individually, hazard rates for drug abuse in offspring of parents with drug abuse were highest for mothers (2.80, 95% CI=2.23–3.38), intermediate for not-lived-with fathers (2.45,95%CI=2.14–2.79), and lowest for stepfathers (1.99, 95% CI=1.55–2.56). The same pattern was seen for alcohol use disorders (2.23, 95% CI=1.93–2.58; 1.84, 95% CI=1.69–2.00; and 1.27, 95% CI=1.12–1.43) and criminal behavior (1.55, 95% CI=1.44–1.66; 1.46, 95%CI=1.40–1.52; and1.30, 95% CI=1.23–1.37). When all three syndromes were examined together, specificity of cross-generational transmission was highest for mothers, intermediate for not-lived-with fathers, and lowest for stepfathers. Analyses of intact families and other not-lived-with parents and stepparents showed similar cross-generation transmission for these syndromes in mothers and fathers, supporting the representativeness of results from triparental families. Conclusions A major strength of the triparental design is its inclusion, within a single family, of parents who provide, to a first approximation, their offspring with genes plus rearing, genes only, and rearing only. For drug abuse, alcohol use disorders, and criminal behavior, the results of this study suggest that parent-offspring transmission involves both genetic and environmental processes, with genetic factors being somewhat more important. These results should be interpreted in the context of the strengths

  6. Implementing a Graduate Certificate Program in Cardiovascular Epidemiology: The Jackson Heart Study

    PubMed Central

    Campbell Jenkins, Brenda W.; Addison, Clifton; Wilson, Gregory; Young, Lavon; Fields, Regina; Woodberry, Clevette; Payton, Marinelle

    2015-01-01

    The Jackson Heart Study (JHS) is committed to providing opportunities for expanding the understanding of the epidemiology, diagnosis, prevention, and treatment of cardiovascular diseases. The JHS Graduate Training and Education Center (GTEC) has initiated the Daniel Hale Williams Scholar (DHWS) program where students are afforded the opportunity to interact with epidemiologists and other biomedical scientists to learn to identify, predict, and prevent cardiovascular disease using the Jackson Heart Study data. This study describes the structured programs developed by JHS GTEC seeking to alleviate the shortage of trained professionals in cardiovascular epidemiology by training graduate students while they complete their academic degrees. The DHWS program provides: (1) an enrichment curriculum; (2) a learning community; (3) quarterly seminars; and (4) a Summer Institute. Students attend enrichment activities comprising: (1) Applied Biostatistics; (2) Cardiovascular Disease Epidemiology; (3) Social Epidemiology; (4) Emerging Topics; and (5) Research Writing. Training focuses on developing proficiency in cardiovascular health knowledge. The DHWS program is a unique strategy for incorporating rigorous academic and career-focused training to graduate students and has enabled the acquisition of competencies needed to impact cardiovascular disease management programs. PMID:26703701

  7. The potential of exposure biomarkers in epidemiologic studies of reproductive health.

    PubMed Central

    Hogue, C J; Brewster, M A

    1991-01-01

    To further the development and application of exposure markers in field investigations in reproductive epidemiology, we have synthesized recent examinations of the issues surrounding exposure measurements in reproductive epidemiology. The specific goals of this paper are to define exposure biomarkers and explore their potential uses, particularly as screening tools. The tests for glucaric acid, thioethers, mutagenicity, and porphyrin patterns meet the general criteria for useful exposure screens. For certain xenobiotic agents, these tests accurately differentiate exposure levels, as demonstrated in occupational and environmental epidemiologic studies. As urinary screens, they are noninvasive and applicable on a large scale with current laboratory techniques. For short-term exposure, glucaric acid, thioethers, and mutagenicity tests are useful. Porphyrin patterns may measure cumulative effects as well as current exposure levels. The usefulness of these tests in epidemiologic studies of environmental effects on reproductive health has yet to be studied. To do so, the battery must be standardized for pregnant women, and test results must be correlated with measured adverse reproductive outcomes, such as gestational length and birthweight. This correlation is particularly important because maternal exposure rather than fetal exposure is being measured. The extent to which xenobiotic chemicals cross the placental barrier may vary greatly depending on the type of exposures, timing in pregnancy, and maternal detoxification capability. Without better exposure measures, epidemiologic studies of reproductive health probably will not successfully identify xenobiotic fetotoxic agents in the environment. However, with an adequate battery of nonspecific exposure biomarkers, prospective studies of environmental effects on pregnancy outcomes might be possible.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2050070

  8. Minimum Cost Estimation of a Baseline Survey for a Molecular Epidemiology Cohort Study: Collecting Participants in a Model Region in Japan

    PubMed Central

    Sawada, Norie; Iwasaki, Motoki; Ohashi, Kayo; Tsugane, Shoichiro

    2016-01-01

    Background Some recent molecular epidemiology studies of the effects of genetic and environmental factors on human health have required the enrollment of more than 100 000 participants and the involvement of regional study offices across the country. Although regional study office investigators play a critical role in these studies, including the acquisition of funds, this role is rarely discussed. Methods We first differentiated the functions of the regional and central study offices. We then investigated the minimum number of items required and approximate cost of a molecular epidemiology study enrolling 7400 participants from a model region with a population of 100 000 for a 4-year baseline survey using a standard protocol developed based on the protocol of Japan Public Health Center-based Prospective Study for the Next Generation. Results The functions of the regional study office were identified, and individual expenses were itemized. The total cost of the 4-year baseline survey was 153 million yen, excluding consumption tax. Accounting difficulties in conducting the survey were clarified. Conclusions We investigated a standardized example of the tasks and total actual costs of a regional study office. Our approach is easy to utilize and will help improve the management of regional study offices in future molecular epidemiology studies. PMID:27001116

  9. [Occupational epidemiology].

    PubMed

    Ahrens, W; Behrens, T; Mester, B; Schmeisser, N

    2008-03-01

    The aim of occupational epidemiology is to describe workplace-related diseases and to identify their underlying causes. Its primary goal is to protect workers from hazardous effects of the working process by applying work-related primary and secondary prevention measures. To assess health risks different study designs and a wide array of complex study instruments and methods are frequently employed that cannot be replaced by toxicological investigations. This paper primarily addresses health risks by agent exposures. In this context a central task of occupational epidemiology is careful assessment of exposure. Different data sources, such as work site measurements, register data, archive material, experts' opinion, and the workers' personal estimates of exposure may be used during this process. In addition, biological markers can complement exposure assessment. Since thorough occupational epidemiologic studies allow assessment of disease risks under realistic exposure conditions, their results should be more frequently used to derive workplace-related threshold limit values. PMID:18311483

  10. Workplace exposure to passive smoking and risk of cardiovascular disease: summary of epidemiologic studies.

    PubMed Central

    Kawachi, I; Colditz, G A

    1999-01-01

    We reviewed the published epidemiologic studies addressing the relationship between workplace exposure to environmental tobacco smoke (ETS) and cardiovascular disease risk in three case-control studies and three cohort studies. Although the point estimates of risk for cardiovascular disease exceeded 1.0 in five of six studies, none of the relative risks was statistically significant because of the small number of cardiovascular end points occurring in individual studies. In common with most epidemiologic investigations of the health risks of ETS, none of the workplace studies included independent biochemical validation of ETS exposure. In contrast to the evidence on increased cardiovascular disease risk from exposure to spousal ETS, studies of ETS exposure in the workplace are still sparse and inconclusive. Conversely, there is no biologically plausible reason to believe that the hazards of ETS exposure that have been demonstrated in the home should not also apply to the workplace. PMID:10592141

  11. Atopic dermatitis is a serious health problem in Poland. Epidemiology studies based on the ECAP study

    PubMed Central

    Raciborski, Filip; Lipiec, Agnieszka; Tomaszewska, Aneta; Lusawa, Adam; Samel-Kowalik, Piotr; Walkiewicz, Artur; Krzych, Edyta; Komorowski, Jarosław; Samoliński, Bolesław

    2015-01-01

    Introduction Global epidemiological studies have revealed considerable geographical differences in prevalence of atopic dermatitis (AD). Aim To present the epidemiology of AD, risk factors and co-occurrence of allergic diseases in the Polish population. Material and methods The present paper is a part of the Epidemiology of Allergic Disorders in Poland study. We studied 22 703 participants by ECRHS/ISAAC questionnaire; 18 617 (53.8% female, 24.2% 6–7 y.o., 25.4% 13–14 y.o., 50.4% 20–44 y.o.) completed questionnaires were accepted. Four thousand seven hundred and eighty-three participants (25.7%) have undergone a medical examination. Results Atopic dermatitis was diagnosed in 3.91% (6–7 y.o. 5.34%, 13–14 y.o. 4.3%, adults 3.02%), more often in females (OR = 1.52; 95% CI: 0.56–0.77), in the cities (OR = 2.23; 95% CI: 1.61–3.09), in mothers (OR = 2.07; 95% CI: 1.72–2.48) and fathers (OR = 2.00; 95% CI: 1.61–2.49) with atopy, higher education (OR = 1.61; 95% CI: 1.11–2.32) and economic status (OR = 1.35; 95% CI: 1.04–1.74). The highest prevalence was found in Katowice (4.89%) and lowest in rural areas (1.9%). Coexisting AD and allergic rhinitis (AR) was found in 26.17%, AR and asthma in 9.09% and AD, AR and asthma in 14.6%. Atopic dermatitis was diagnosed by allergologists in 6.5% (6–7 y.o. 8.7%, 13–14 y.o. 9.0%, adults 3.6%). Most diagnoses were made in Poznan (16.76%) and smallest in rural area (3.67%). 78.8% of subjects were diagnosed with AD for the first time although they had earlier experienced its symptoms. Conclusions Atopic dermatitis prevalence in Poland is below the mean rate for Europe, but the risk factor profile is similar to other countries. Atopic dermatitis is more frequent in well-educated females with atopic parents and high socioeconomic status and who live in a city. PMID:25821420

  12. Extracting Primary Open-Angle Glaucoma from Electronic Medical Records for Genetic Association Studies.

    PubMed

    Restrepo, Nicole A; Farber-Eger, Eric; Goodloe, Robert; Haines, Jonathan L; Crawford, Dana C

    2015-01-01

    Electronic medical records (EMRs) are being widely implemented for use in genetic and genomic studies. As a phenotypic rich resource, EMRs provide researchers with the opportunity to identify disease cohorts and perform genotype-phenotype association studies. The Epidemiologic Architecture for Genes Linked to Environment (EAGLE) study, as part of the Population Architecture using Genomics and Epidemiology (PAGE) I study, has genotyped more than 15,000 individuals of diverse genetic ancestry in BioVU, the Vanderbilt University Medical Center's biorepository linked to a de-identified version of the EMR (EAGLE BioVU). Here we develop and deploy an algorithm utilizing data mining techniques to identify primary open-angle glaucoma (POAG) in African Americans from EAGLE BioVU for genetic association studies. The algorithm described here was designed using a combination of diagnostic codes, current procedural terminology billing codes, and free text searches to identify POAG status in situations where gold-standard digital photography cannot be accessed. The case algorithm identified 267 potential POAG subjects but underperformed after manual review with a positive predictive value of 51.6% and an accuracy of 76.3%. The control algorithm identified controls with a negative predictive value of 98.3%. Although the case algorithm requires more downstream manual review for use in large-scale studies, it provides a basis by which to extract a specific clinical subtype of glaucoma from EMRs in the absence of digital photographs.

  13. Extracting Primary Open-Angle Glaucoma from Electronic Medical Records for Genetic Association Studies

    PubMed Central

    Restrepo, Nicole A.; Farber-Eger, Eric; Goodloe, Robert; Haines, Jonathan L.; Crawford, Dana C.

    2015-01-01

    Electronic medical records (EMRs) are being widely implemented for use in genetic and genomic studies. As a phenotypic rich resource, EMRs provide researchers with the opportunity to identify disease cohorts and perform genotype-phenotype association studies. The Epidemiologic Architecture for Genes Linked to Environment (EAGLE) study, as part of the Population Architecture using Genomics and Epidemiology (PAGE) I study, has genotyped more than 15,000 individuals of diverse genetic ancestry in BioVU, the Vanderbilt University Medical Center’s biorepository linked to a de-identified version of the EMR (EAGLE BioVU). Here we develop and deploy an algorithm utilizing data mining techniques to identify primary open-angle glaucoma (POAG) in African Americans from EAGLE BioVU for genetic association studies. The algorithm described here was designed using a combination of diagnostic codes, current procedural terminology billing codes, and free text searches to identify POAG status in situations where gold-standard digital photography cannot be accessed. The case algorithm identified 267 potential POAG subjects but underperformed after manual review with a positive predictive value of 51.6% and an accuracy of 76.3%. The control algorithm identified controls with a negative predictive value of 98.3%. Although the case algorithm requires more downstream manual review for use in large-scale studies, it provides a basis by which to extract a specific clinical subtype of glaucoma from EMRs in the absence of digital photographs. PMID:26061293

  14. Childhood Brain Tumor Epidemiology: A Brain Tumor Epidemiology Consortium Review

    PubMed Central

    Johnson, Kimberly J.; Cullen, Jennifer; Barnholtz-Sloan, Jill S.; Ostrom, Quinn T.; Langer, Chelsea E.; Turner, Michelle C.; McKean-Cowdin, Roberta; Fisher, James L.; Lupo, Philip J.; Partap, Sonia; Schwartzbaum, Judith A.; Scheurer, Michael E.

    2014-01-01

    Childhood brain tumors are the most common pediatric solid tumor and include several histological subtypes. Although progress has been made in improving survival rates for some subtypes, understanding of risk factors for childhood brain tumors remains limited to a few genetic syndromes and ionizing radiation to the head and neck. In this report, we review descriptive and analytical epidemiology childhood brain tumor studies from the past decade and highlight priority areas for future epidemiology investigations and methodological work that is needed to advance our understanding of childhood brain tumor causes. Specifically, we summarize the results of a review of studies published since 2004 that have analyzed incidence and survival in different international regions and that have examined potential genetic, immune system, developmental and birth characteristics, and environmental risk factors. PMID:25192704

  15. Epidemiological data of 290 pemphigus vulgaris patients: a 29-year retrospective study.

    PubMed

    Baum, Sharon; Astman, Nadav; Berco, Efraim; Solomon, Michal; Trau, Henri; Barzilai, Aviv

    2016-08-01

    Pemphigus vulgaris (PV), an autoimmune blistering disease involving the skin and mucosa, is traditionally considered to be prevalent among Jews, particularly those of Ashkenazi origin. Israel, where the Ashkenazi and non-Ashkenazi Jewish population live alongside a large Arab minority, is a particularly interesting place for epidemiological studies of PV. To characterise the epidemiological and clinical parameters of PV patients from a single tertiary medical centre in Israel. Data was retrieved retrospectively from the medical records of newly diagnosed PV patients referred to the Sheba Medical Center between 1980 and 2009. A total of 290 PV patients were diagnosed during the study period. The mean age at diagnosis was 49.7 years (range: 10-92 years) and a female predominance was identified (1.54:1; p<0.001). Among the Jewish patients, the ratio of Ashkenazi to non-Ashkenazi was 1.23:1, which was not statistically significant in comparison to the ratio of the general Jewish population in Israel (p = 0.289). We describe the comorbidities found among the patients. Disease severity at diagnosis was not found to be related to the epidemiological parameters examined. Studies from different countries reveal variations in the clinical and epidemiological characteristics of the disease. The epidemiology of PV in Israel, a Middle-Eastern country with a Western lifestyle and a diverse ethnic population, shows some characteristics that represent an "admixture" between European and Middle-Eastern or Asian countries. The associated comorbidities of PV emphasize the need for dermatologists to keep a high index of suspicion and actively evaluate patients to determine their presence. PMID:27300747

  16. Cognitive epidemiology

    PubMed Central

    Deary, Ian J; Batty, G David

    2007-01-01

    This glossary provides a guide to some concepts, findings and issues of discussion in the new field of research in which intelligence test scores are associated with mortality and morbidity. Intelligence tests are devised and studied by differential psychologists. Some of the major concepts in differential psychology are explained, especially those regarding cognitive ability testing. Some aspects of IQ (intelligence) tests are described and some of the major tests are outlined. A short guide is given to the main statistical techniques used by differential psychologists in the study of human mental abilities. There is a discussion of common epidemiological concepts in the context of cognitive epidemiology. PMID:17435201

  17. Los Alamos National Laboratory: A guide to records series supporting epidemiologic studies conducted for the Department of Energy

    SciTech Connect

    1997-01-01

    The purpose of this guide is to describe each series of records that pertains to the epidemiologic studies conducted by the Epidemiology Section of the Occupational Medicine Group (ESH-2) at the Department of Energy`s (DOE) Los Alamos National Laboratory (LANL) in Los Alamos, New Mexico. The records described in this guide relate to occupational studies performed by the Epidemiology Section, including those pertaining to workers at LANL, Mound Plant, Oak Ridge Reservation, Pantex Plant, Rocky Flats Plant, and Savannah River Site. Also included are descriptions of other health-related records generated or collected by the Epidemiology Section and a small set of records collected by the Industrial Hygiene and Safety Group. This guide is not designed to describe the universe of records generated by LANL which may be used for epidemiologic studies of the LANL work force. History Associates Incorporated (HAI) prepared this guide as part of its work as the support services contractor for DOE`s Epidemiologic Records Inventory Project. This introduction briefly describes the Epidemiologic Records Inventory Project, HAI`s role in the project, the history of LANL the history and functions of LANL`s Health Division and Epidemiology Section, and the various epidemiologic studies performed by the Epidemiology Section. It provides information on the methodology that HAI used to inventory and describe records housed in the offices of the LANL Epidemiology Section in Technical Area 59 and at the LANL Records Center. Other topics include the methodology used to produce the guide, the arrangement of the detailed record series descriptions, and information concerning access to records repositories.

  18. SEVERITY OF ILLNESS RESULTS FOR EPIDEMIOLOGIC RECREATIONAL WATER STUDIES

    EPA Science Inventory

    The NEEAR Water Study surveyed 21,105 beachgoers at four freshwater coastal beaches. It has been well documented that beachgoers experience more illness than persons that do not frequent beach areas. Reported symptoms among beachgoers for this study are gastrointestinal illness...

  19. Carbon Nanotubes Exposure Risk Assessment: From Toxicology to Epidemiologic Studies (Overview of the Current Problem)

    PubMed Central

    Fatkhutdinova, L. M.; Khaliullin, T. O.; Shvedova, A. A.

    2015-01-01

    Nanoscale size and fiber like structure of carbon nanotubes (CNTs) may determine high reactivity and penetration, as well as the pathogenicity of asbestos and other mineral fibers. Despite many in vitro and in vivo studies, the absence of full-scale data on CNT effects on human health clearly point out the necessity for epidemiological studies. Currently, several projects are initiated worldwide on studying health risks associated with the inhalation of industrial CNTs, including NIOSH-promoted research (United States), the European CANTES study, and the Russian CNT-ERA project. Studies comprising several successive steps, such as CNT exposure assessment in occupational settings, toxicological evaluation, and epidemiological observations, are critical for determining material safety and use criteria. PMID:26457172

  20. Automated Assay of Telomere Length Measurement and Informatics for 100,000 Subjects in the Genetic Epidemiology Research on Adult Health and Aging (GERA) Cohort

    PubMed Central

    Lapham, Kyle; Kvale, Mark N.; Lin, Jue; Connell, Sheryl; Croen, Lisa A.; Dispensa, Brad P.; Fang, Lynn; Hesselson, Stephanie; Hoffmann, Thomas J.; Iribarren, Carlos; Jorgenson, Eric; Kushi, Lawrence H.; Ludwig, Dana; Matsuguchi, Tetsuya; McGuire, William B.; Miles, Sunita; Quesenberry, Charles P.; Rowell, Sarah; Sadler, Marianne; Sakoda, Lori C.; Smethurst, David; Somkin, Carol P.; Van Den Eeden, Stephen K.; Walter, Lawrence; Whitmer, Rachel A.; Kwok, Pui-Yan; Risch, Neil; Schaefer, Catherine; Blackburn, Elizabeth H.

    2015-01-01

    The Kaiser Permanente Research Program on Genes, Environment, and Health (RPGEH) Genetic Epidemiology Research on Adult Health and Aging (GERA) cohort includes DNA specimens extracted from saliva samples of 110,266 individuals. Because of its relationship to aging, telomere length measurement was considered an important biomarker to develop on these subjects. To assay relative telomere length (TL) on this large cohort over a short time period, we created a novel high throughput robotic system for TL analysis and informatics. Samples were run in triplicate, along with control samples, in a randomized design. As part of quality control, we determined the within-sample variability and employed thresholds for the elimination of outlying measurements. Of 106,902 samples assayed, 105,539 (98.7%) passed all quality control (QC) measures. As expected, TL in general showed a decline with age and a sex difference. While telomeres showed a negative correlation with age up to 75 years, in those older than 75 years, age positively correlated with longer telomeres, indicative of an association of longer telomeres with more years of survival in those older than 75. Furthermore, while females in general had longer telomeres than males, this difference was significant only for those older than age 50. An additional novel finding was that the variance of TL between individuals increased with age. This study establishes reliable assay and analysis methodologies for measurement of TL in large, population-based human studies. The GERA cohort represents the largest currently available such resource, linked to comprehensive electronic health and genotype data for analysis. PMID:26092717

  1. How much soil do young children ingest: an epidemiologic study.

    PubMed

    Calabrese, E J; Barnes, R; Stanek, E J; Pastides, H; Gilbert, C E; Veneman, P; Wang, X R; Lasztity, A; Kostecki, P T

    1989-10-01

    Sixty-four children aged 1-4 years were evaluated for the extent to which they ingest soil. The study followed the soil tracer methodology of S. Binder, D. Sokal, and D. Maughan (1986, Arch. Environ. Health, 41, 341-345). However, the present study included a number of modifications from the Binder et al. study. The principal new features were (1) increasing the tracer elements from three to eight; (2) using a mass-balance approach so that the contribution of food and medicine ingestion would be considered; (3) extending the period of observation from 3 days to 8 days; and (4) validating the methodology by having adult volunteers ingest known amounts of soil in a mass-balance validation study. The principal findings reveal the following. (1) The adult study confirmed the validity of the tracer methodology to estimate soil ingestion. (2) Of the eight tracers employed in the adult study, only Al, Si, and Y provided sufficient recovery data that was directly acceptably stable and reliable. (3) If food ingestion determinations were taken into consideration, the median estimates of soil ingestion from the eight tracers ranged from a low of 9 mg/day (Y) to a high of 96 mg/day (V); the median values of Al, Si, and Y, the three most reliable tracers, ranged from 9 mg/day to 40 mg/day. (4) One child had soil ingestion values ranging from 5 to 8 g/day, depending on the tracer. (5) If food ingestion had not been considered, the estimates of soil ingestion would have increased about two- to sixfold, depending on the tracer with Ti and Y being most affected by food intake. (6) Since soil and dust samples did not significantly differ in their levels of tracer elements, no reliable differentiation between the contribution of ingestion of dust and soil could be made. (7) These findings are generally consistent with the previously reported findings of Binder et al. (1986) and P. Clausing, B. Brunekreff, and J.H. van Wijnen (1987, Int. Arch. Occup. Med., 59, 73) if these latter

  2. International Lymphoma Epidemiology Consortium

    Cancer.gov

    The InterLymph Consortium, or formally the International Consortium of Investigators Working on Non-Hodgkin's Lymphoma Epidemiologic Studies, is an open scientific forum for epidemiologic research in non-Hodgkin's lymphoma.

  3. Uses of available record systems in epidemiologic studies of reproductive toxicology.

    PubMed

    Polednak, A P; Janerich, D T

    1983-01-01

    The uses of available record systems in epidemiologic studies of reproductive toxicology are described with reference to New York State. The available record systems (and relevant reproductive end points) described include: a newborn screening program for metabolic diseases and hemoglobinopathies (relevant to point mutations); chromosome registries and prenatal cytogenetics (for chromosome anomalies); live birth certificates (for birth defects, birthweight, sex ratio, etc); fetal death certificates (for spontaneous fetal deaths); and a statewide cancer registry (for childhood cancers and transplacental carcinogenesis). The uses and limitations of these record systems are discussed, along with examples of their use in descriptive and analytic epidemiologic studies. Descriptive studies outlined include investigations of temporal and geographic trends in birth defects, birth weight, and fetal deaths, with reference to environmental questions (eg, Love Canal, nuclear power plants). Analytic studies described concern parental occupation in relation to specific birth defects (neural tube defects and Down syndrome) and maternal use of contraceptive drugs. PMID:6220602

  4. Uses of available record systems in epidemiologic studies of reproductive toxicology

    SciTech Connect

    Polednak, A.P.; Janerich, D.T.

    1983-01-01

    The uses of available record systems in epidemiologic studies of reproductive toxicology are described with reference to New York State. The available record systems (and relevant reproductive end points) described include: a newborn screening program for metabolic diseases and hemoglobinopathies (relevant to point mutations); chromosome registries and prenatal cytogenetics (for chromosome anomalies); live birth certificates (for birth defects, birthweight, sex ratio, etc); fetal death certificates (for spontaneous fetal deaths); and a statewide cancer registry (for childhood cancers and transplacental carcinogenesis). The uses and limitations of these record systems are discussed, along with examples of their use in descriptive and analytic epidemiologic studies. Descriptive studies outlined include investigations of temporal and geographic trends in birth defects, birth weight, and fetal deaths, with reference to environmental questions (eg, Love Canal, nuclear power plants). Analytic studies described concern parental occupation in relation to specific birth defects (neural tube defects and Down syndrome) and maternal use of contraceptive drugs.

  5. Pesticide Exposure and Neurodevelopmental Outcomes: Review of the Epidemiologic and Animal Studies

    PubMed Central

    Burns, Carol J.; McIntosh, Laura J.; Mink, Pamela J.; Jurek, Anne M.; Li, Abby A.

    2013-01-01

    Assessment of whether pesticide exposure is associated with neurodevelopmental outcomes in children can best be addressed with a systematic review of both the human and animal peer-reviewed literature. This review analyzed epidemiologic studies testing the hypothesis that exposure to pesticides during pregnancy and/or early childhood is associated with neurodevelopmental outcomes in children. Studies that directly queried pesticide exposure (e.g., via questionnaire or interview) or measured pesticide or metabolite levels in biological specimens from study participants (e.g., blood, urine, etc.) or their immediate environment (e.g., personal air monitoring, home dust samples, etc.) were eligible for inclusion. Consistency, strength of association, and dose response were key elements of the framework utilized for evaluating epidemiologic studies. As a whole, the epidemiologic studies did not strongly implicate any particular pesticide as being causally related to adverse neurodevelopmental outcomes in infants and children. A few associations were unique for a health outcome and specific pesticide, and alternative hypotheses could not be ruled out. Our survey of the in vivo peer-reviewed published mammalian literature focused on effects of the specific active ingredient of pesticides on functional neurodevelopmental endpoints (i.e., behavior, neuropharmacology and neuropathology). In most cases, effects were noted at dose levels within the same order of magnitude or higher compared to the point of departure used for chronic risk assessments in the United States. Thus, although the published animal studies may have characterized potential neurodevelopmental outcomes using endpoints not required by guideline studies, the effects were generally observed at or above effect levels measured in repeated-dose toxicology studies submitted to the U.S. Environmental Protection Agency (EPA). Suggestions for improved exposure assessment in epidemiology studies and more effective

  6. Epidemiological studies of taste function: discussion and perspectives.

    PubMed

    Snyder, Derek J; Bartoshuk, Linda M

    2009-07-01

    Efforts to quantify the public health impact of chemosensation present significant challenges, including a strong need for testing methods suitable for field assessment. This discussion highlights several promising approaches to the population-based study of taste function; it also identifies key principles that should be considered when adapting laboratory-based taste tests for field use. PMID:19686195

  7. Epidemiological studies of taste function: Discussion and perspectives

    PubMed Central

    Snyder, Derek J.; Bartoshuk, Linda M.

    2009-01-01

    Efforts to quantify the public health impact of chemosensation present significant challenges, including a strong need for testing methods suitable for field assessment. This discussion highlights several promising approaches to the population-based study of taste function; it also identifies key principles that should be considered when adapting laboratory-based taste tests for field use. PMID:19686195

  8. Epidemiological Findings of Pervasive Developmental Disorders in a Venezuelan Study

    ERIC Educational Resources Information Center

    Montiel-Nava, Cecilia; Pena, Joaquin A.

    2008-01-01

    The study aims to determine the prevalence of autism spectrum disorders (ASDs) for children receiving services in Maracaibo County, Venezuela. Children aged 3-9 with diagnosis of any ASD were recruited. We ascertained area, referral process, and definitions of ASD for each patient. A total of 430 children were identified, and 76.5 percent were…

  9. Accidents related to manure in eastern Switzerland: an epidemiological study.

    PubMed Central

    Knoblauch, A; Steiner, B; Bachmann, S; Trachsler, G; Burgheer, R; Osterwalder, J

    1996-01-01

    OBJECTIVES: Liquid manure systems and manure pits are major hazards in the agricultural workplace. The incidence of accidents related to manure is unknown. The objective of this study was to survey the liquid manure facilities of farms in eastern Switzerland and find the incidence of accidents related to manure in the region. METHODS: Retrospective cohort study and cross sectional survey of 210 farms in eastern Switzerland. RESULTS: The incidence of accidents related to manure was found to be 10.4/1000 person-years. Most accidents were categorised as minor--that is, had a benign outcome for the people involved or involved animals only. One in 33 of the farms surveyed was the scene of an accident related to manure each year. CONCLUSIONS: The medical literature on accidents related to manure mostly reports accidents with catastrophic outcomes. This study shows that this type of accident is only the tip of the iceberg. Most of the accidents reported in this study belong to a category that has hitherto been un-noticed and unreported. The term "accident related to manure" covers a broad range of events, and those resulting in serious human illness or death represent only a small part of this spectrum. A wide variety of liquid manure systems were found on the farms surveyed. Very few liquid manure facilities conformed to published safety standards. PMID:8882112

  10. [Epidemiological study on respiratory effects of smoking in college students].

    PubMed

    Nozu, Y

    1993-06-01

    To study the influence of smoking on the respiratory system in adolescents, we conducted a prospective study to look into the respiratory symptoms, changes in ventilatory function, and levels of expired CO of both smoking and nonsmoking college students. The subjects were 56 male students who entered Akita University in 1986. Thirty of the participants were smokers at entrance whereas the rest who were nonsmokers, served as controls. The smokers started smoking at an average age of 17.6 +/- 0.9 years. Physical examinations at 8 points during the study were performed periodically in May and November for four years, from 1986 to 1989. From these studies, the following conclusions were obtained. 1) The prevalence of respiratory symptoms, especially phlegm, was higher among the smokers compared with the nonsmokers; the differences not being significant. Among both the smokers and nonsmokers, no prevalence of persistent cough and phlegm was observed during the study period. 2) There were no differences in the levels of %FVC and %V50 between the smokers and the nonsmokers at any point during the study period. The FEV1% levels for smokers were decreased progressively, and the differences became significant at the 7th and 8th tests (p < 0.05). After the second test, %V25 levels were lower in the smokers than in the nonsmokers; the differences being significant at the 7th test (p < 0.05). 3) The dose-response relationships between smoking and pulmonary function were not statistically significant in any levels at the 7th and 8th tests. However, %V25 levels of the heavy smokers (15 < or = per a day) were lower than the those of the nonsmokers; the differences being significant at the 7th and 8th tests (p < 0.05). 4) Average expired CO concentrations of the smokers were 2.5-3.5 times higher than those of the nonsmokers during the study period, confirming exposure to tobacco smoke. These observations suggest that young smokers may develop obstructive changes, especially

  11. A Critical Assessment of Epidemiology Studies Regarding Dietary/Supplemental Zinc and Prostate Cancer Risk

    PubMed Central

    Costello, Leslie C.; Franklin, Renty B.; Tan, Ming T.

    2013-01-01

    Despite the prevalence of prostate cancer, the etiology and factors associated with its development and progression are largely unknown. An important relationship in prostate cancer is the role of zinc. Clinical evidence and experimental evidence have established that prostate cancer is associated with a decrease in the zinc uptake and accumulation in the malignant cells; and that the accumulation of zinc in the prostate cells prevents malignancy. In contrast to this established consistent clinical relationship, numerous epidemiology studies and reports of the effect of dietary and supplemental zinc on the incidence of prostate cancer have provided divergent, inconsistent, and inconclusive results; which range from adverse effects of zinc, protective effects of zinc, and no effect of zinc on the risk of prostate cancer. Despite these divergent and inconclusive results, a prevailing view and public warning has evolved from unsubstantiated and uncorroborated epidemiology studies that zinc consumption increases the risk of developing advanced stage prostate cancer. Such a conclusion is not well-founded and has serious, confusing and erroneous implications for the medical/scientific community and for the public-at-large. The admonition of Dimitrios Trichopoulos over a decade ago [1] that, “… (epidemiology) studies will inevitably generate false positive and false negative results with disturbing frequency. …, when (people) do take us seriously, we may unintentionally do more harm than good” can be applied to the situation that is the subject of this report. Therefore it is extremely important to review the epidemiology studies that have lead to the conclusion of an adverse effect of zinc, and also that have produced such inconsistent and divergent results. This critical review defines issues, problems, and shortcomings that exist in the conduct, conclusions, and dissemination of the epidemiology studies. We caution that one should be knowledgeable and

  12. On the biological effects of cosmic rays: Epidemiological study

    NASA Astrophysics Data System (ADS)

    Conforto, A. M.; Signorini, C.

    1991-04-01

    The determination of the biological effects of cosmic rays and other natural radiation to resolve the more general problem of the consequences on human health, from the basis of ionizing radiation, is addressed. Difficulties relating to an epmidemiological study are outlined and results are discussed particularly concerning their inconsistency. In particular, high and low doses are discussed, referencing the Hiroshima bomb, the HBRA (High Background Radiation Area), and the CA (Control Area). High and low regions are discussed for the case of cancer.

  13. [Significance of field epidemiologic study to identification of chronic arsenic poisoning].

    PubMed

    Su, Li-Qin; Jin, Yin-Long

    2005-09-01

    Chronic arsenic poisoning has serious and extensive impact on human health, which attracts wide attention worldwide. Bases on vast public survey, this article introduces recent field studies on chronic arsenic poisoning from three aspects: exposure history, clinical symptoms and laboratory evidences, and also explains the meaning of each index to the determination of chronic arsenic poisoning, then bring forward some considerations on further epidemiological studies on chronic arsenic poisoning. PMID:16329618

  14. [Significance of field epidemiologic study to identification of chronic arsenic poisoning].

    PubMed

    Su, Li-Qin; Jin, Yin-Long

    2005-09-01

    Chronic arsenic poisoning has serious and extensive impact on human health, which attracts wide attention worldwide. Bases on vast public survey, this article introduces recent field studies on chronic arsenic poisoning from three aspects: exposure history, clinical symptoms and laboratory evidences, and also explains the meaning of each index to the determination of chronic arsenic poisoning, then bring forward some considerations on further epidemiological studies on chronic arsenic poisoning.

  15. Collecting Fecal Samples for Microbiome Analyses in Epidemiology Studies

    PubMed Central

    Sinha, Rashmi; Chen, Jun; Amir, Amnon; Vogtmann, Emily; Shi, Jianxin; Inman, Kristin S.; Flores, Roberto; Sampson, Joshua; Knight, Rob; Chia, Nicholas

    2016-01-01

    Background The need to develop valid methods for sampling and analyzing fecal specimens for microbiome studies is increasingly important, especially for large population studies. Methods Some of the most important attributes of any sampling method are reproducibility, stability, and accuracy. We compared seven fecal sampling methods (no additive, RNAlater, 70% ethanol, EDTA, dry swab, and pre/post development fecal occult blood test (FOBT)) using 16S rRNA microbiome profiling in two laboratories. We evaluated nine commonly used microbiome metrics: abundance of 3 phyla, two alpha-diversities, and four beta-diversities. We determined the technical reproducibility, stability at ambient temperature, and accuracy. Results While microbiome profiles showed systematic biases according to sample method and time at ambient temperature, the highest source of variation was between individuals. All collection methods showed high reproducibility. FOBT and RNAlater resulted in the highest stability without freezing for four days. In comparison to no-additive samples, swab, FOBT, and 70% ethanol exhibited the greatest accuracy when immediately frozen. Conclusions Overall, optimal stability and reproducibility was achieved using FOBT, making this a reasonable sample collection method for 16s analysis. Impact Having standardized method of collecting and storing stable fecal samples will allow future investigations into the role of gut microbiota in chronic disease etiology in large population studies. PMID:26604270

  16. Epidemiological and immunopathological studies on Porcine parvovirus infection in Punjab

    PubMed Central

    Kaur, Amninder; Mahajan, V.; Leishangthem, G. D.; Singh, N. D.; Bhat, Payal; Banga, H. S.; Filia, G.

    2016-01-01

    Aim: The aim of this study was to get the first-hand knowledge about the seroprevalence of Porcine parvovirus (PPV) in Punjab and a diagnosis of PPV from abortion cases of swine using gross, histopathological, and immunohistopathological techniques to observe the tissue tropism of the virus strain. Materials and Methods: Tissue samples from the reproductive tract of pig (n=32), placental tissue (n=10), and aborted fetuses (n=18) were collected from Postmortem Hall of the Department of Veterinary Pathology, GADVASU, field outbreaks and from butcher houses in and around Ludhiana. These samples were processed for histopathological and immunohistochemical (IHC) studies. For seroprevalence study, 90 serum samples of different sex and age were collected from 15 swine farms of Punjab and were subjected to indirect enzyme linked immunosorbent assay using commercial kit. Results: Overall, seroprevalence of PPV was found to be 41.1%. Sex and age related difference in the prevalence was noted. In abortion cases grossly congested and emphysematous lungs, congested internal organs with fluid in abdominal cavity and congestion in brain, changes were noted in fetuses, while diffuse hemorrhages and edema was observed in placental tissue. Histopathologically, the most frequent fetal lesions in aborted fetuses were noted in lungs, liver, and brain. IHC staining revealed PPV antigens in sections of heart, liver, lung, spleen, brain, lymph node of fetuses, placenta, and uterus of sow. Gross, histopathological, and IHC examination of the samples confirmed 5 fetus, 2 placenta and 3 female reproductive samples positive for parvovirus infection. Conclusions: Seroprevalence results may serve as a support either in prevention or control of the disease. IHC is the sensitive technique for diagnosis of PPV associated with the reproductive tract of swine and was found to supplement the gross and histopathological alterations, respectively, associated with the disease. PMID:27651669

  17. Epidemiological and immunopathological studies on Porcine parvovirus infection in Punjab

    PubMed Central

    Kaur, Amninder; Mahajan, V.; Leishangthem, G. D.; Singh, N. D.; Bhat, Payal; Banga, H. S.; Filia, G.

    2016-01-01

    Aim: The aim of this study was to get the first-hand knowledge about the seroprevalence of Porcine parvovirus (PPV) in Punjab and a diagnosis of PPV from abortion cases of swine using gross, histopathological, and immunohistopathological techniques to observe the tissue tropism of the virus strain. Materials and Methods: Tissue samples from the reproductive tract of pig (n=32), placental tissue (n=10), and aborted fetuses (n=18) were collected from Postmortem Hall of the Department of Veterinary Pathology, GADVASU, field outbreaks and from butcher houses in and around Ludhiana. These samples were processed for histopathological and immunohistochemical (IHC) studies. For seroprevalence study, 90 serum samples of different sex and age were collected from 15 swine farms of Punjab and were subjected to indirect enzyme linked immunosorbent assay using commercial kit. Results: Overall, seroprevalence of PPV was found to be 41.1%. Sex and age related difference in the prevalence was noted. In abortion cases grossly congested and emphysematous lungs, congested internal organs with fluid in abdominal cavity and congestion in brain, changes were noted in fetuses, while diffuse hemorrhages and edema was observed in placental tissue. Histopathologically, the most frequent fetal lesions in aborted fetuses were noted in lungs, liver, and brain. IHC staining revealed PPV antigens in sections of heart, liver, lung, spleen, brain, lymph node of fetuses, placenta, and uterus of sow. Gross, histopathological, and IHC examination of the samples confirmed 5 fetus, 2 placenta and 3 female reproductive samples positive for parvovirus infection. Conclusions: Seroprevalence results may serve as a support either in prevention or control of the disease. IHC is the sensitive technique for diagnosis of PPV associated with the reproductive tract of swine and was found to supplement the gross and histopathological alterations, respectively, associated with the disease.

  18. A clinico-epidemiological study of rescuer burns.

    PubMed

    Basra, Baljeet Kumar; Suri, Manav P; Patil, Nilesh; Atha, Ravish; Patel, Natvar; Sachde, Jayesh P; Shaikh, M F

    2014-08-01

    Rescuer burn is a relatively newer terminology introduced to define the burns sustained by a person attempting to rescue a primary burn victim. Few studies have been published thus far on this peculiar type of burns. Due to the general neglect of the rescuer burns victim and discontinuation of treatment in most cases, once the primary victim dies, the rescuer often ends up in badly infected wounds and has a delayed return to work. A prospective study was conducted at the B J Medical College and Civil Hospital, Ahmedabad from January 2009 to December 2012 on the rescuer burns patients treated in its burns and plastic surgery department. 3074 patients of burns received treatment during the period of study. Of these, 48 patients gave the history of sustaining burns while trying to rescue a burns victim. Male to female ratio of rescuers was approximately 7:1. It was significantly higher as compared to the ratio of 1:0.8 of females to male burn victims observed at our centre (p≤0.01). Average age of the rescuers was higher in males as compared to females but the difference was not significant (p≥0.05). Of the 45 cases of female primary burns victims, male rescuer was husband of the primary victim in 41/45 cases (91.1%), mother was rescuer in three cases (6.6% cases) and sister was rescuer in one case. Though multiple people came to rescue a burns victim, in all cases, it was seen that it was the first rescuer who sustained burns himself or herself. None of the rescuers had any knowledge of the techniques and precautions to be taken while performing a rescue operation irrespective of their education status, indirectly pointing to the lack of any teaching on burns rescue in the school education curriculum.

  19. [Epidemiological study of nosocomial meningitis in neurological patients].

    PubMed

    Ostabal, M I; Suárez Pinilla, M A; Sanz Sebastián, C; Millastre, A

    1996-03-01

    We realized a retrospective study of all the patients who developed a nosocomial meningitis after to admitted to the Intensive Care Unit of our hospital, during the last five years. Nosocomial meningitis was found in 3.29% of the neurologic patients. The most frequent causes of the meningitis was the external ventricular drainage (14.8%), post-neurosurgical (0.8%) and head injury (0.0007%). The causative bacterias were stafilococo, S. pneumoniae, K. pneunomiae and P. aeruginosa. The mortality was of the 39.06%.

  20. Using Accelerometers to Measure Physical Activity in Large-Scale Epidemiologic Studies: Issues and Challenges

    PubMed Central

    Lee, I-Min; Shiroma, Eric J

    2013-01-01

    Background Current guidelines for aerobic activity require that adults carry out ≥150 minutes/week of moderate-intensity physical activity, with a large body of epidemiologic evidence showing this level of activity to decrease the incidence of many chronic diseases. Less is known about whether light-intensity activities also have such benefits, and whether sedentary behavior is an independent predictor of increased risks of these chronic diseases, as imprecise assessments of these behaviours and cross-sectional study designs have limited knowledge to date. Methods Recent technological advances in assessment methods have made the use of movement sensors, such as the accelerometer, feasible for use in longitudinal, large-scale epidemiologic studies. Several such studies are collecting sensor-assessed, objective measures of physical activity with the aim of relating these to the development of clinical endpoints. This is a relatively new area of research; thus, in this paper, we use the Women’s Health Study (WHS) as a case study to illustrate challenges related to data collection, data processing, and analyses of the vast amount of data collected. Results The WHS plans to collect 7 days of accelerometer-assessed physical activity and sedentary behavior in ~18,000 women aged ≥62 years. Several logistical challenges exist in collecting data; nonetheless as of 31 August 2013, 11,590 women have already provided some data. Additionally, the WHS experience on data reduction and data analyses can help inform other similar large-scale epidemiologic studies. Conclusions Important data on the health effects of light-intensity activity and sedentary behaviour will emerge from large-scale epidemiologic studies collecting objective assessments of these behaviours. PMID:24297837

  1. Recent evidence from epidemiological studies on methylmercury toxicity.

    PubMed

    Murata, Katsuyuki; Yoshida, Minoru; Sakamoto, Mineshi; Iwai-Shimada, Miyuki; Yaginuma-Sakurai, Kozue; Tatsuta, Nozomi; Iwata, Toyoto; Karita, Kanae; Nakai, Kunihiko

    2011-09-01

    More than fifty years have passed since the outbreak of Minamata disease, and large-scale methylmercury poisoning due to industrial effluents or methylmercury-containing fungicide intoxication has scarcely happened in developed countries. On the other hand, widespread environmental mercury contamination has occurred in gold and mercury mining areas of developing countries. In this article, we provided an overview of recent studies addressing human health effects of methylmercury, which we searched using the PubMed of the US National Library of Medicine. The following suggestions were obtained for low-level methylmercury exposure: (1) In recent years, the proportion of human studies addressing methylmercury has tended to decrease. (2) Prenatal exposure to methylmercury through fish intake, even at low levels, adversely affects child development after adjusting for polychlorinated biphenyls and maternal fish intake during pregnancy, whereas maternal seafood intake has some benefits. (3) Long-term methylmercury exposure through consumption of fish such as bigeye tuna and swordfish may pose a potential risk of cardiac events involving sympathovagal imbalance. (4) In measuring methylmercury levels in preserved umbilical cord collected from inhabitants born in Minamata areas between 1945 and 1989, the elevated concentrations (≥1 mg/g) were observed mainly in inhabitants born between 1947 and 1968, and the peak coincided with the peak of acetaldehyde production in Minamata. (5) Since some developing countries appear to be in similar situations to Japan in the past, attention should be directed toward early recognition of a risky agent and precautions should be taken against it.

  2. Skin tears in institutionalized elderly: an epidemiological study.