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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 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

  3. Genetic Epidemiology of Tuberculosis Susceptibility: Impact of Study Design

    PubMed Central

    Stein, Catherine M.

    2011-01-01

    Several candidate gene studies have provided evidence for a role of host genetics in susceptibility to tuberculosis (TB). However, the results of these studies have been very inconsistent, even within a study population. Here, we review the design of these studies from a genetic epidemiological perspective, illustrating important differences in phenotype definition in both cases and controls, consideration of latent M. tuberculosis infection versus active TB disease, population genetic factors such as population substructure and linkage disequilibrium, polymorphism selection, and potential global differences in M. tuberculosis strain. These considerable differences between studies should be accounted for when examining the current literature. Recommendations are made for future studies to further clarify the host genetics of TB. PMID:21283783

  4. The 20th century Danish facial cleft population--epidemiological and genetic-epidemiological studies.

    PubMed

    Christensen, K

    1999-03-01

    Since Dr. Fogh-Andersen's legendary 1942 thesis, the Danish facial cleft population has been one of the most extensively studied in terms of epidemiology and genetic-epidemiology. The etiology of cleft lip and/or palate (CLP) is still largely an enigma, and different results concerning environmental and genetic risk factors are obtained in different countries and regions. This may be due to etiological heterogeneity between settings. Therefore, an in-depth studied area with an ethnically homogeneous population, such as Denmark, has provided one of the best opportunities for progress in CLP etiological research. The present review summarizes epidemiological and genetic-epidemiological studies conducted in the 20th century Danish facial cleft population. Furthermore, analyses of sex differences, time trends and seasonality for more than 7000 CLP cases born in Denmark in the period 1936 to 1987 are presented. The review also points toward the excellent opportunities for continued etiological CLP research in Denmark in the 21st century using already established resources and an on-going prospective cohort study of 100,000 pregnant women. PMID:10213053

  5. 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

  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. Genetic Epidemiology of Psoriasis

    PubMed Central

    Gupta, Rashmi; Debbaneh, Maya G.; Liao, Wilson

    2014-01-01

    Psoriasis is a chronic, inflammatory, immune-mediated skin condition with a prevalence of 0-11.8% across the world. It is associated with a number of cardiovascular, metabolic, and autoimmune disease co-morbidities. Psoriasis is a multifactorial disorder, influenced by both genetic and environmental factors. Its genetic basis has long been established through twin studies and familial clustering. The association of psoriasis with the HLA-Cw6 allele has been shown in many studies. Recent genome-wide association studies have identified a large number of other genes associated with psoriasis. Many of these genes regulate the innate and adaptive immune system. These findings indicate that a dysregulated immune system may play a major role in the pathogenesis of psoriasis. In this article, we review the clinical and genetic epidemiology of psoriasis with a brief description of the pathogenesis of disease. PMID:25580373

  8. 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

  9. 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

  10. Association of genetic variants with hypertension in a longitudinal population-based genetic epidemiological study

    PubMed Central

    YAMADA, YOSHIJI; MATSUI, KOTA; TAKEUCHI, ICHIRO; OGURI, MITSUTOSHI; FUJIMAKI, TETSUO

    2015-01-01

    We previously identified 9 genes and chromosomal region 3q28 as susceptibility loci for Japanese patients with myocardial infarction, ischemic stroke, or chronic kidney disease by genome-wide or candidate gene association studies. In the present study, we investigated the possible association of 13 single nucleotide polymorphisms (SNPs) at these 10 loci with the prevalence of hypertension or their association with blood pressure (BP) in community-dwelling individuals in Japan. The study subjects comprised 6,027 individuals (2,250 subjects with essential hypertension, 3,777 controls) who were recruited into the Inabe Health and Longevity Study, a longitudinal genetic epidemiological study on atherosclerotic, cardiovascular and metabolic diseases. The subjects were recruited from individuals who visited the Health Care Center of Inabe General Hospital for an annual health checkup, and they are followed up each year (mean follow-up period, 5 years). Longitudinal analysis with a generalized estimating equation and with adjustment for age, gender, body mass index and smoking status revealed that rs2116519 of family with sequence similarity 78, member B (FAM78B; P=0.0266), rs6929846 of butyrophilin, subfamily 2, member A1 (BTN2A1; P= 0.0013), rs146021107 of pancreatic and duodenal homeobox 1 (PDX1; P=0.0031) and rs1671021 of lethal giant larvae homolog 2 (Drosophila) (LLGL2; P=0.0372) were significantly (P<0.05) associated with the prevalence of hypertension. Longitudinal analysis with a generalized linear mixed-effect model and with adjustment for age, gender, body mass index and smoking status among individuals not taking anti-hypertensive medication revealed that rs6929846 of BTN2A1 was significantly associated with systolic (P=0.0017), diastolic (P=0.0008) and mean (P=0.0005) BP, and that rs2116519 of FAM78B, rs146021107 of PDX1 and rs1671021 of LLGL2 were significantly associated with diastolic (P=0.0495), systolic (P=0.0132), and both diastolic (P=0.0468) and mean

  11. 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

  12. The genetic study of three population microisolates in South Tyrol (MICROS): study design and epidemiological perspectives

    PubMed Central

    Pattaro, Cristian; Marroni, Fabio; Riegler, Alice; Mascalzoni, Deborah; Pichler, Irene; Volpato, Claudia B; Dal Cero, Umberta; De Grandi, Alessandro; Egger, Clemens; Eisendle, Agatha; Fuchsberger, Christian; Gögele, Martin; Pedrotti, Sara; Pinggera, Gerd K; Stefanov, Stefan A; Vogl, Florian D; Wiedermann, Christian J; Meitinger, Thomas; Pramstaller, Peter P

    2007-01-01

    Background There is increasing evidence of the important role that small, isolated populations could play in finding genes involved in the etiology of diseases. For historical and political reasons, South Tyrol, the northern most Italian region, includes several villages of small dimensions which remained isolated over the centuries. Methods The MICROS study is a population-based survey on three small, isolated villages, characterized by: old settlement; small number of founders; high endogamy rates; slow/null population expansion. During the stage-1 (2002/03) genealogical data, screening questionnaires, clinical measurements, blood and urine samples, and DNA were collected for 1175 adult volunteers. Stage-2, concerning trait diagnoses, linkage analysis and association studies, is ongoing. The selection of the traits is being driven by expert clinicians. Preliminary, descriptive statistics were obtained. Power simulations for finding linkage on a quantitative trait locus (QTL) were undertaken. Results Starting from participants, genealogies were reconstructed for 50,037 subjects, going back to the early 1600s. Within the last five generations, subjects were clustered in one pedigree of 7049 subjects plus 178 smaller pedigrees (3 to 85 subjects each). A significant probability of familial clustering was assessed for many traits, especially among the cardiovascular, neurological and respiratory traits. Simulations showed that the MICROS pedigree has a substantial power to detect a LOD score ≥ 3 when the QTL specific heritability is ≥ 20%. Conclusion The MICROS study is an extensive, ongoing, two-stage survey aimed at characterizing the genetic epidemiology of Mendelian and complex diseases. Our approach, involving different scientific disciplines, is an advantageous strategy to define and to study population isolates. The isolation of the Alpine populations, together with the extensive data collected so far, make the MICROS study a powerful resource for the study

  13. The relation of ADHD and violent aggression: What can we learn from epidemiological and genetic studies?

    PubMed

    Retz, Wolfgang; Rösler, Michael

    2009-01-01

    Disruptive behavior includes psychopathological and behavioral constructs like aggression, impulsivity, violence, antisociality and psychopathy and is often closely related with diagnostic categories like conduct disorder (CD), attention deficit disorder (ADHD) and antisocial personality disorder (ASP). There is now clear evidence that neurobiological and environmental factors contribute to these phenotypes. A mounting body of evidence also suggests interactive effects of genetic and environmental risks. In this selective review we give an overview over epidemiological aspects of the relation between ADHD and antisocial behavior, including violent aggression and psychopathy. Moreover, we summarize recent findings from molecular genetic studies and particularly discuss pleiotropic effects of a functional polymorphism of the serotonin transporter promoter gene (5HTTLPR) and childhood adversity on ADHD and violent behavior. The reported gene-environment interactions are not only informative for understanding the neurobiological underpinnings of disruptive behavior, but also throw some light on the relation between ADHD and violent behavior from a genetic perspective. The impact of genetic research on forensic psychiatry and future directions of neurobiological research are discussed. PMID:19411109

  14. Genetic epidemiology of melanoma.

    PubMed

    Ribero, Simone; Glass, Dan; Bataille, Veronique

    2016-08-01

    The field of melanoma genetics is moving at great pace with new platforms to investigate single nucleotide polymorphism, genome sequencing, gene expression, and methylation. Melanoma incidence is still rising mainly because of screening campaigns, which has increased the number of reported melanomas. However, mortality due to melanoma is not decreasing. Many cutaneous phenotypic risk factors have been linked to melanoma, but the association with UV radiation is very complex. The level of vitamin D affects both the risk of melanoma and prognosis, but more studies are needed. The genetics of melanoma involves genes involved in pigmentation and naevi, as well as genes involved in the cell cycle and senescence, which have been identified via genome-wide association studies over the last 10 years. One area of research highly relevant to melanoma is telomere biology with further links to reduced senescence. At the somatic level, new gene pathways are being explored with many new therapeutic targets, and boosting immune responses against the tumour appears to offer the best long-term outcome. PMID:27436815

  15. Genetic epidemiological study of schizophrenia in Palau, Micronesia: prevalence and familiality.

    PubMed

    Myles-Worsley, M; Coon, H; Tiobech, J; Collier, J; Dale, P; Wender, P; Reimherr, F; Polloi, A; Byerley, W

    1999-02-01

    We are studying the genetic etiology of schizophrenia in the Republic of Palau, a remote island nation in Micronesia that has been geographically and ethnically isolated for approximately 2,000 years. The first epidemiological phase sought to estimate the lifetime prevalence of schizophrenia and evaluate the familiality of the illness based on complete ascertainment of cases and families segregating schizophrenia. A total of 160 strictly defined cases of schizophrenia were ascertained in a population of 13,750 adults who were 15 years of age and older. The lifetime prevalence of strictly defined schizophrenia in Palau was 1.99% overall and 2.77% in males vs. 1.24% in females. This greater than 2:1 male-to-female risk ratio for schizophrenia was accompanied by an earlier mean age of onset for males (23.3 years) than for females (27.5 years). These 160 cases of strict schizophrenia represent 59 separate families each identified by a single common founder. Eleven of these families have 5 to 14 cases and represent nearly half of the strict schizophrenia cases in Palau. Although schizophrenia is clearly aggregating in these 11 families, cases are distributed sparsely throughout the large sibships. In the entire sample of 160 cases of strict schizophrenia, there were only 11 sib-pairs and 2 sib-trios. When a family was defined to include third-degree relatives, only 11 cases (6.9%) were nonfamilial. The majority of the ascertained cases can be linked together into extended pedigrees with complex multilineal inheritance patterns. These intricately interconnected families may pose challenges for traditional linkage techniques. However, these Palauan families represent a valuable resource for studying the genetic etiology of schizophrenia because there may be fewer susceptibility genes for schizophrenia in this genetic isolate than in the heterogeneous populations that are common throughout the world today. PMID:10050960

  16. Familial transmission of schizophrenia in Palau: A 20-year genetic epidemiological study in three generations.

    PubMed

    Myles-Worsley, Marina; Tiobech, Josepha; Blailes, Francisca; Middleton, Frank A; Vinogradov, Sophia; Byerley, William; Faraone, Stephen V

    2011-04-01

    Our genetic epidemiological studies of schizophrenia and other psychotic disorders (SCZ) in the isolated population of Palau have been ongoing for 20 years. Results from the first decade showed that Palau has an elevated prevalence of SCZ and that cases cluster in extended multigenerational pedigrees interconnected via complex genetic relationships after centuries of endogamous, but not consanguineous, marriages. The aim of our second decade of research, which extended data collection into a third generation of young, high-risk (HR) Palauans, was to identify significant predictors of intergenerational transmission of illness. Our findings revealed that degree of familial loading and gender effects on reproductive fitness are important modifiers of risk for transmission of SCZ. Among 45 distinct multiplex families, we identified 10 high-density (HD) Palauan families, each with 7-29 SCZ cases, which contain half of Palau's 260 SCZ cases and 80% of the 113 SCZ cases with one or more affected first-degree relatives, indicating that familial loading is a major risk factor for SCZ in Palau. Cases that belong to multiply affected sibships are more common than cases with an affected parent. Furthermore, only 6/38 multiply affected sibships have an affected parent, strong evidence that many unaffected parents are obligate carriers of susceptibility genes. Although reproductive fitness is dramatically reduced in affected males, the 30% minority who do become fathers are twice as likely as affected mothers to transmit SCZ to an offspring. As they evolve, these HD families can help to elucidate the genetic mechanisms that predict intergenerational transmission of SCZ. PMID:21294248

  17. Association of genetic variants with coronary artery disease and ischemic stroke in a longitudinal population-based genetic epidemiological study

    PubMed Central

    YAMADA, YOSHIJI; MATSUI, KOTA; TAKEUCHI, ICHIRO; FUJIMAKI, TETSUO

    2015-01-01

    Our previous studies identified nine genes and chromosomal region 3q28 as susceptibility loci for myocardial infarction, ischemic stroke or chronic kidney disease by genome-wide or candidate gene association studies. As coronary artery disease (CAD) and ischemic stroke may share genetic architecture, certain genetic variants may confer susceptibility to the two diseases. The present study examined the association of 13 polymorphisms at these 10 loci with the prevalence of CAD or ischemic stroke in community-dwelling individuals, with the aim of identifying genetic variants that confer susceptibility to the two conditions. Study subjects (170 with CAD, 117 with ischemic stroke and 5,718 controls) were recruited to the Inabe Health and Longevity Study, a longitudinal genetic epidemiological study of atherosclerotic, cardiovascular and metabolic diseases. The subjects were recruited from individuals who visited for an annual health checkup and they were followed up each year (mean follow-up period, 5 years). Longitudinal analysis with a generalized estimating equation, and with adjustment for age, gender, body mass index, smoking status, the prevalence of hypertension, diabetes mellitus and dyslipidemia and the serum concentration of creatinine, revealed that rs2074380 (G→A) and rs2074381 (A→G) of the α-kinase 1 (ALPK1) gene and rs8089 (T→G) of the thrombospondin 2 (THBS2) gene were significantly (P<2×10−16) associated with the prevalence of CAD, with the AA genotype of rs2074380 and GG genotypes of rs2074381 and rs8089 being protective against this condition. Similar analysis revealed that rs9846911 (A→G) at chromosome 3q28, rs2074381 of ALPK1, rs8089 of THBS2 and rs6046 (G→A) of the coagulation factor VII gene were significantly (P<2×10−16) associated with the prevalence of ischemic stroke, with the GG genotypes of rs9846911, rs2074381 and rs8089 and the AA genotype of rs6046 being protective against this condition. ALPK1 and THBS2 may thus be

  18. 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.

  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. PMID:11161412

  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. Association of genetic variants with dyslipidemia and chronic kidney disease in a longitudinal population-based genetic epidemiological study

    PubMed Central

    YAMADA, YOSHIJI; MATSUI, KOTA; TAKEUCHI, ICHIRO; FUJIMAKI, TETSUO

    2015-01-01

    We previously identified 9 genes and chromosomal region 3q28 as susceptibility loci for myocardial infarction, ischemic stroke, or chronic kidney disease (CKD) in Japanese individuals by genome-wide or candidate gene association studies. In the present study, we examined the association of 13 polymorphisms at these 10 loci with the prevalence of hypertriglyceridemia, hyper-low-density lipoprotein (LDL) cholesterolemia, hypo-high-density lipoprotein (HDL) cholesterolemia, or CKD in community-dwelling Japanese individuals. The study subjects comprised 6,027 individuals who were recruited to the Inabe Health and Longevity Study, a longitudinal genetic epidemiological study of atherosclerotic, cardiovascular and metabolic diseases. The subjects were recruited from individuals who visited the Health Care Center at Inabe General Hospital for an annual health checkup, and they were followed up each year (mean follow-up period, 5 years). Longitudinal analysis with a generalized estimating equation and with adjustment for covariates revealed that rs6929846 of butyrophilin, subfamily 2, member A1 gene (BTN2A1) was significantly associated with the prevalence of hypertriglyceridemia (P=0.0001), hyper-LDL cholesterolemia (P=0.0004), and CKD (P=0.0007); rs2569512 of interleukin enhancer binding factor 3 (ILF3) was associated with hyper-LDL cholesterolemia (P=0.0029); and rs2074379 (P=0.0019) and rs2074388 (P=0.0029) of alpha-kinase 1 (ALPK1) were associated with CKD. Longitudinal analysis with a generalized linear mixed-effect model and with adjustment for covariates among all individuals revealed that rs6929846 of BTN2A1 was significantly associated with the serum concentrations of triglycerides (P=0.0011), LDL cholesterol (P=3.3×10−5), and creatinine (P=0.0006), as well as with the estimated glomerular filtration rate (eGFR) (P=0.0004); rs2569512 of ILF3 was shown to be associated with the serum concentration of LDL cholesterol (P=0.0221); and rs2074379 (P=0.0302) and rs

  2. Path analysis in genetic epidemiology: a critique.

    PubMed Central

    Karlin, S; Cameron, E C; Chakraborty, R

    1983-01-01

    Path analysis, a form of general linear structural equation models, is used in studies of human genetics data to discern genetic, environmental, and cultural factors contributing to familial resemblance. It postulates a set of linear and additive parametric relationships between phenotypes and genetic and cultural variables and then essentially uses the assumption of multivariate normality to estimate and perform tests of hypothesis on parameters. Such an approach has been advocated for the analysis of genetic epidemiological data by D. C. Rao, N. Morton, C. R. Cloninger, L. J. Eaves, and W. E. Nance, among others. This paper reviews and evaluates the formulations, assumptions, methodological procedures, interpretations, and applications of path analysis. To give perspective, we begin with a discussion of path analysis as it occurs in the form of general linear causal models in several disciplines of the social sciences. Several specific path analysis models applied to lipoprotein concentrations, IQ, and twin data are then reviewed to keep the presentation self-contained. The bulk of the critical discussion that follows is directed toward the following four facets of path analysis: (1) coherence of model specification and applicability to data; (2) plausibility of modeling assumptions; (3) interpretability and utility of the model; and (4) validity of statistical and computational procedures. In the concluding section, a brief discussion of the problem of appropriate model selection is presented, followed by a number of suggestions of essentially model-free alternative methods of use in the treatment of complex structured data such as occurs in genetic epidemiology. PMID:6349335

  3. Plasma adiponectin concentrations and correlates in African Americans in the Hypertension Genetic Epidemiology Network (HyperGEN) study.

    PubMed

    Shikany, James M; Lewis, Cora E; Freedman, Barry I; Arnett, Donna K; Leiendecker-Foster, Catherine; Jones, Tamekia L; Redden, David T; Oberman, Albert

    2007-08-01

    Adiponectin has demonstrated insulin-sensitizing, antiatherogenic, and anti-inflammatory properties, and may be an important risk factor for coronary heart disease and diabetes. Relatively few previous studies of plasma adiponectin have included sizable numbers of African Americans. The objective of the study was to investigate plasma concentrations of adiponectin and correlates of these concentrations in African Americans. This was a cross-sectional analysis that took place within the Hypertension Genetic Epidemiology Network. This study included 211 normotensive offspring (aged 22-37 years) of hypertensive siblings recruited by the Hypertension Genetic Epidemiology Network Birmingham, AL, field center. In addition to measuring plasma adiponectin, demographic and lifestyle data were collected, and anthropometric, clinical, and laboratory measurements were obtained. Mean plasma adiponectin concentration was 5.5+/-3.8 microg/mL. Adiponectin was 55% higher in women than in men: 6.5+/-4.4 vs 4.2+/-2.5 microg/mL, respectively (P<.0001). In a multivariable analysis, high-density lipoprotein cholesterol concentration was positively associated and male sex and insulin concentration were negatively associated with plasma adiponectin concentration. Plasma adiponectin concentrations in these African Americans were lower than those reported in other racial/ethnic groups, including Japanese, whites, and Pima Indians. The directions of the associations of plasma adiponectin with other factors were in agreement with results in other racial/ethnic groups. PMID:17618943

  4. Merozoite surface protein-3 alpha as a genetic marker for epidemiologic studies in Plasmodium vivax: a cautionary note

    PubMed Central

    2013-01-01

    Background Plasmodium vivax is the most widespread of the human malaria parasites in terms of geography, and is thought to present unique challenges to local efforts aimed at control and elimination. Parasite molecular markers can provide much needed data on P. vivax populations, but few such markers have been critically evaluated. One marker that has seen extensive use is the gene encoding merozoite surface protein 3-alpha (MSP-3α), a blood-stage antigen known to be highly variable among P. vivax isolates. Here, a sample of complete msp-3α gene sequences is analysed in order to assess its utility as a molecular marker for epidemiologic investigations. Methods Amplification, cloning and sequencing of additional P. vivax isolates from different geographic locations, including a set of Venezuelan field isolates (n = 10), yielded a sample of 48 complete msp-3α coding sequences. Characterization of standard population genetic measures of diversity, phylogenetic analysis, and tests for recombination were performed. This allowed comparisons to patterns inferred from the in silico simulation of a polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) protocol used widely. Results The larger sample of MSP-3α diversity revealed incongruence between the observed levels of nucleotide polymorphism, which were high in all populations, and the pattern of PCR-RFLP haplotype diversity. Indeed, PCR-RFLP haplotypes were not informative of a population’s genetic diversity and identical haplotypes could be produced from analogous bands in the commonly used protocol. Evidence of frequent and variable insertion-deletion mutations and recurrent recombination between MSP-3α haplotypes complicated the inference of genetic diversity patterns and reduced the phylogenetic signal. Conclusions The genetic diversity of P. vivax msp-3α involves intragenic recombination events. Whereas the high genetic diversity of msp-3α makes it a promising marker for some

  5. Genetic epidemiology of rheumatoid arthritis.

    PubMed Central

    Lynn, A H; Kwoh, C K; Venglish, C M; Aston, C E; Chakravarti, A

    1995-01-01

    We conducted family studies and segregation analyses of rheumatoid arthritis (RA) that were based on consecutive patients with RA ascertained without regard to family history or known risk factors. First-degree relatives from 135 simplex and 30 multiplex families were included in the analyses. A highly penetrant recessive major gene, with a mutant allele frequency of .005, was identified as the most parsimonious genetic risk factor. Significant evidence for heterogeneity in risk for RA was observed for proband gender but not for proband age at onset. Kaplan-Meier risk analysis demonstrated significant evidence for differences in the distribution of risk among first-degree relatives. These analyses demonstrated that both proband gender and age at onset are important risk factors but that proband gender appears to be the more important determinant of risk, with relatives of male probands having the greatest cumulative risk for RA. In addition, log-linear modeling identified proband gender, familiality (multiplex or simplex), and an interaction term between these two variables as being adequate to define the distribution of risk in families. The pattern of risk for RA among susceptible individuals and its inheritance is thus heterogeneous. For future genetic analyses, families with an excess of affected males having a young age at onset may be the most informative in identifying the putative recessive gene and its modifiers. PMID:7611283

  6. 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. PMID:26505319

  7. The genetic epidemiology of multiple sclerosis.

    PubMed Central

    Compston, A

    1999-01-01

    Epidemiological studies have implicated an interplay between genetic and environmental factors in the aetiology of multiple sclerosis (MS). There is a familial recurrence rate of approximately 15%. Meta-analysis of the recurrence risk shows that the rate is highest overall for siblings, then parents and children, with lower rates in second- and third-degree relatives. Recurrence is highest for monozygotic twins. Conversely, the frequency in adoptees is similar to the population lifetime risk. The age-adjusted risk for half siblings is also less than for full siblings. Recurrence is higher in the children of conjugal pairs with MS than the offspring of single affected. These classical genetic observations suggest that MS is a complex trait in which susceptibility is determined by several genes acting independently or epistatically. Comparisons between co-affected sibling pairs provide no evidence for correlation with age or year at onset and mode of presentation or disability. Thus far, the identification of susceptibility genes has proved elusive but genetic strategies are now in place which should illuminate the problem. The main dividend will be an improved understanding of the pathogenesis. To date, population studies have demonstrated an association between the class II major histocompatibility complex (MHC) alleles DR15 and DQ6 and their corresponding genotypes. An association with DR4, with or without the primary DR15 link, is seen in some Mediterranean populations. Candidate gene approaches have otherwise proved unrewarding. Four groups of investigators have undertaken a systematic search of the genome. In common with most other complex traits, no major susceptibility gene has been identified but regions of interest have been provisionally identified. These genetic analyses are predicated on the assumption that MS is one disease. Genotypic and phenotypic analyses are beginning to question this assumption. A major part of future studies in the genetics of MS

  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 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

  9. 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

  10. Multi-stage sampling in genetic epidemiology.

    PubMed

    Whittemore, A S; Halpern, J

    When data are expensive to collect, it can be cost-efficient to sample in two or more stages. In the first stage a simple random sample is drawn and then stratified according to some easily measured attribute. In each subsequent stage a random subset of previously selected units is sampled for more detailed observation, with a unit's sampling probability determined by its attributes as observed in the previous stages. These designs are useful in many medical studies; here we use them in genetic epidemiology. Two genetic studies illustrate the strengths and limitations of the approach. The first study evaluates nuclear and mitochondrial DNA in U.S. blacks. The goal is to estimate the relative contributions of white male genes and white female genes to the gene pool of African-Americans. This example shows that the Horvitz-Thompson estimators proposed for multi-stage designs can be inefficient, particularly when used with unnecessary stratification. The second example is a multi-stage study of familial prostate cancer. The goal is to gather pedigrees, blood samples and archived tissue for segregation and linkage analysis of familial prostate cancer data by first obtaining crude family data from prostate cancer cases and cancer-free controls. This second example shows the gains in efficiency from multi-stage sampling when the individual likelihood or quasilikelihood scores vary substantially across strata. PMID:9004389

  11. 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

  12. Huntington disease: genetics and epidemiology.

    PubMed Central

    Conneally, P M

    1984-01-01

    Huntington disease (HD) is an autosomal dominant disorder in which the major gene expression occurs in the central nervous system. It is characterized by the appearance of progressive chorea and dementia, usually in adult life. One tragic aspect of the disorder, due to its late age of onset and, until recently, lack of a presymptomatic marker, is that transmission of the disease to offspring invariably occurs before symptoms develop in the parent. Although the onset of symptoms and the rate of progression may vary, the prognosis is one of relentless deterioration. The major pathological features of HD are a primary loss of cells in the caudate nucleus and putamen (striatum) but other regions of the basal ganglia, hypothalamus, and brain stem are also involved. Not only is there neuronal loss but there is also a decrease in the level of a number of neurotransmitters and associated enzymes, together with abnormalities in some receptor sites. Martin [1] described the disease as "genetically programmed cell death in the human central nervous system." PMID:6233902

  13. 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

  14. Genetic Variation and Reproductive Timing: African American Women from the Population Architecture Using Genomics and Epidemiology (PAGE) Study

    PubMed Central

    Carty, Cara L.; Franceschini, Nora; Fernández-Rhodes, Lindsay; Young, Alicia; Cheng, Iona; Ritchie, Marylyn D.; Haiman, Christopher A.; Wilkens, Lynne; ChunyuanWu; Matise, Tara C.; Carlson, Christopher S.; Brennan, Kathleen; Park, Amy; Rajkovic, Aleksandar; Hindorff, Lucia A.

    2013-01-01

    Age at menarche (AM) and age at natural menopause (ANM) define the boundaries of the reproductive lifespan in women. Their timing is associated with various diseases, including cancer and cardiovascular disease. Genome-wide association studies have identified several genetic variants associated with either AM or ANM in populations of largely European or Asian descent women. The extent to which these associations generalize to diverse populations remains unknown. Therefore, we sought to replicate previously reported AM and ANM findings and to identify novel AM and ANM variants using the Metabochip (n = 161,098 SNPs) in 4,159 and 1,860 African American women, respectively, in the Women’s Health Initiative (WHI) and Atherosclerosis Risk in Communities (ARIC) studies, as part of the Population Architecture using Genomics and Epidemiology (PAGE) Study. We replicated or generalized one previously identified variant for AM, rs1361108/CENPW, and two variants for ANM, rs897798/BRSK1 and rs769450/APOE, to our African American cohort. Overall, generalization of the majority of previously-identified variants for AM and ANM, including LIN28B and MCM8, was not observed in this African American sample. We identified three novel loci associated with ANM that reached significance after multiple testing correction (LDLR rs189596789, p = 5×10−08; KCNQ1 rs79972789, p = 1.9×10−07; COL4A3BP rs181686584, p = 2.9×10−07). Our most significant AM association was upstream of RSF1, a gene implicated in ovarian and breast cancers (rs11604207, p = 1.6×10−06). While most associations were identified in either AM or ANM, we did identify genes suggestively associated with both: PHACTR1 and ARHGAP42. The lack of generalization coupled with the potentially novel associations identified here emphasize the need for additional genetic discovery efforts for AM and ANM in diverse populations. PMID:23424626

  15. 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.

  16. Genetic/epidemiological findings in a study of smoking-associated tumors.

    PubMed

    Lynch, H T; Fain, P R; Albano, W A; Ruma, T; Black, L; Lynch, J; Shonka, M

    1982-06-01

    While the etiology of bronchogenic carcinoma remains enigmatic, an expanding array of carcinogenic pollutants in interaction with host susceptibility factors has been implicated. We have studied family histories of cancer in a consecutive series of cancer patients from two university oncology clinics in Nebraska. Particular attention has been given to carcinoma of the lung and other putative smoking-associated cancers (oral cavity, esophagus, urinary bladder, pancreas). Smoking histories were obtained for relatives of an overlapping series of patients with these tumor sites. Findings revealed that, although a significant cohort effect was observed with respect to smoking habits for both relatives of lung cancer probands and for relatives of probands with other smoking-associated tumors, a corresponding trend for lung cancer frequency was observed only for relatives of lung cancer probands. This result suggests the importance of host factors in combination with environmental exposures in determining lung risk. A cohort trend for lung cancer was also apparent among relatives of breast cancer probands, but not for relatives of colon cancer probands, suggesting the possibility of an intrinsic association between carcinomas of the breast and lung. We believe that further elucidation of host factor susceptibility in lung cancer may have important etiological and preventive implications. PMID:7104988

  17. 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

  18. Genome-Wide Gene-Sodium Interaction Analyses on Blood Pressure: The Genetic Epidemiology Network of Salt-Sensitivity Study.

    PubMed

    Li, Changwei; He, Jiang; Chen, Jing; Zhao, Jinying; Gu, Dongfeng; Hixson, James E; Rao, Dabeeru C; Jaquish, Cashell E; Gu, Charles C; Chen, Jichun; Huang, Jianfeng; Chen, Shufeng; Kelly, Tanika N

    2016-08-01

    We performed genome-wide analyses to identify genomic loci that interact with sodium to influence blood pressure (BP) using single-marker-based (1 and 2 df joint tests) and gene-based tests among 1876 Chinese participants of the Genetic Epidemiology Network of Salt-Sensitivity (GenSalt) study. Among GenSalt participants, the average of 3 urine samples was used to estimate sodium excretion. Nine BP measurements were taken using a random zero sphygmomanometer. A total of 2.05 million single-nucleotide polymorphisms were imputed using Affymetrix 6.0 genotype data and the Chinese Han of Beijing and Japanese of Tokyo HapMap reference panel. Promising findings (P<1.00×10(-4)) from GenSalt were evaluated for replication among 775 Chinese participants of the Multi-Ethnic Study of Atherosclerosis (MESA). Single-nucleotide polymorphism and gene-based results were meta-analyzed across the GenSalt and MESA studies to determine genome-wide significance. The 1 df tests identified interactions for UST rs13211840 on diastolic BP (P=3.13×10(-9)). The 2 df tests additionally identified associations for CLGN rs2567241 (P=3.90×10(-12)) and LOC105369882 rs11104632 (P=4.51×10(-8)) with systolic BP. The CLGN variant rs2567241 was also associated with diastolic BP (P=3.11×10(-22)) and mean arterial pressure (P=2.86×10(-15)). Genome-wide gene-based analysis identified MKNK1 (P=6.70×10(-7)), C2orf80 (P<1.00×10(-12)), EPHA6 (P=2.88×10(-7)), SCOC-AS1 (P=4.35×10(-14)), SCOC (P=6.46×10(-11)), CLGN (P=3.68×10(-13)), MGAT4D (P=4.73×10(-11)), ARHGAP42 (P≤1.00×10(-12)), CASP4 (P=1.31×10(-8)), and LINC01478 (P=6.75×10(-10)) that were associated with at least 1 BP phenotype. In summary, we identified 8 novel and 1 previously reported BP loci through the examination of single-nucleotide polymorphism and gene-based interactions with sodium. PMID:27271309

  19. 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

  20. Association of genetic variants of the α-kinase 1 gene with type 2 diabetes mellitus in a longitudinal population-based genetic epidemiological study

    PubMed Central

    YAMADA, YOSHIJI; MATSUI, KOTA; TAKEUCHI, ICHIRO; OGURI, MITSUTOSHI; FUJIMAKI, TETSUO

    2015-01-01

    Previously, our studies identified nine genes and the chromosomal region 3q28 as susceptibility loci for myocardial infarction, ischemic stroke or chronic kidney disease in individuals by genome-wide or candidate gene association studies. The present study examined the possible association of 13 polymorphisms at these 10 loci with the prevalence of type 2 diabetes mellitus (DM) in community-dwelling individuals. Study subjects comprised 6,027 individuals (797 subjects with type 2 DM and 5,230 controls) who were recruited to the Inabe Health and Longevity Study, a longitudinal genetic epidemiological study of atherosclerotic, cardiovascular and metabolic diseases. The subjects were recruited from individuals who visited for an annual health checkup and they were followed up each year (mean follow-up, 5 years). Longitudinal analysis with a generalized estimating equation and with adjustment for age, gender and body mass index (BMI) revealed that rs2116519 (C→T) of FAM78B (P=0.0188), as well as rs2074379 (G→A, P=0.0121) and rs2074388 (A→G, P=0.0053) of ALPK1 were significantly (P<0.05) associated with the prevalence of type 2 DM. Longitudinal analysis with a generalized linear mixed-effect model and with adjustment for age, gender and BMI among all the individuals revealed that rs2116519, rs2074379 and rs2074388 were significantly associated with fasting plasma glucose level (P=0.0352, 0.0017 and 0.0010, respectively) and to blood glycosylated hemoglobin (hemoglobin A1c) content (P=0.0065, 0.0090 and 0.0079, respectively). Similar analysis among individuals not taking antidiabetic medication revealed that rs2074379 and rs2074388 were associated with the fasting plasma glucose level (P=0.0073 and 0.0042, respectively) and blood hemoglobin A1c content (P=0.0142 and 0.0126, respectively), whereas rs2116519 was associated with blood hemoglobin A1c content only (P=0.0470). ALPK1 may thus be a susceptibility gene for type 2 DM. PMID:26137234

  1. 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

  2. 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

  3. Granuloma annulare: Clinical and histologic variants, epidemiology, and genetics.

    PubMed

    Piette, Evan W; Rosenbach, Misha

    2016-09-01

    Granuloma annulare (GA) is a poorly understood condition characterized by a set of clinical morphologic variants with 2 predominant histopathologic patterns of inflammation. This review provides a comprehensive overview of the available information about the clinical variants and histopathologic features, current epidemiologic data, and potential genetic underpinnings of GA. Much of the current understanding of GA is based on retrospective studies, case series, and case reports; this review aims to synthesize the available information and present it clearly for practicing dermatologists. PMID:27543209

  4. [Epidemiologic and genetic studies of canine hip dysplasia in a population of Labrador retrievers: a study over 25 years].

    PubMed

    Ohlerth, S; Busato, A; Gaillard, C; Flückiger, M; Lang, J

    1998-10-01

    The occurrence of canine hip dysplasia (CHD) was analyzed in a colony of 738 Labrador Retrievers between 1972 and 1996. Of these dogs, 86.3% were radiographically examined for hip dysplasia. The overall prevalence of CHD was 31.3% during the study period of 25 years. Between 1972 and 1980, the prevalence of CHD was 57.9%. It decreased to 14.9% between 1991 and 1996. Univariate and multivariate logistic regression models were developed to identify the influence of potential risk factors for CHD such as age at examination, gender, color, year and season of birth, litter size, order of birth, birth weight, body weight and daily weight gain. Birth year and age at examination proved to be significant risk factors. No significant association was found between CHD and elbow dysplasia. Of the dogs diagnosed with CHD, 18% showed dysplastic changes only, without radiographic signs of secondary osteoarthritis (OA). The Norberg angle (NA) proved to be a significant risk factor for coxofemoral osteoarthritis with a moderate negative correlation between OA and NA. Finally, genetic effects were calculated in a mixed model. Heritability (h2) of CHD was estimated at 0.53 (SE = 0.17) for paternal half siblings. The proportion of the common environment of a litter to the total variance was estimated at C2 = 0.03. PMID:9818525

  5. 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

  6. The Epidemiology and Genetics of Uterine Leiomyoma.

    PubMed

    Styer, Aaron K; Rueda, Bo R

    2016-07-01

    Uterine leiomyomas (fibroids) are the most common benign neoplasms in premenopausal women, which confer significant morbidity during the reproductive years and represent a significant public health issue. The incidence of fibroids has been associated with African-American race, early onset of menarche, early parity, and environmental/dietary exposures. These sex steroid-responsive uterine tumors are characterized by de novo transformation of the myometrium into fibroids via excessive formation of the extracellular matrix (ECM). Cytogenic anomalies, mutations in mediator complex subunit 12 (MED 12), and aberrant DNA methylation/demethylation have been observed, but have not been reported as direct mediators of fibroid development. Recent advances in epigenetics have implied a functional role of G protein-coupled receptor 10 (GPR10) overexpression and irregular microRNA expression in the pathobiology of fibroids that require future investigation. Herein, the impact of epidemiologic and genetic factors on the incidence and development of fibroids is reviewed. PMID:26725703

  7. Genetic epidemiology of cardiometabolic risk ractors and their clustering patterns in Mexican American children and adolescents: The SAFARI Study

    PubMed Central

    Fowler, Sharon P.; Puppala, Sobha; Arya, Rector; Chittoor, Geetha; Farook, Vidya S.; Schneider, Jennifer; Resendez, Roy G.; Upadhayay, Ram Prasad; VandeBerg, Jane; Hunt, Kelly J.; Bradshaw, Benjamin; Cersosimo, Eugenio; VandeBerg, John L.; Almasy, Laura; Curran, Joanne E.; Comuzzie, Anthony G.; Lehman, Donna M.; Jenkinson, Christopher P.; Lynch, Jane L.; DeFronzo, Ralph A.; Blangero, John; Hale, Daniel E.; Duggirala, Ravindranath

    2013-01-01

    Pediatric metabolic syndrome (MS) and its cardiometabolic components (MSCs) have become increasingly prevalent, yet little is known about the genetics underlying MS risk in children. We examined the prevalence and genetics of MS-related traits among 670 non-diabetic Mexican American (MA) children and adolescents, aged 6–17 years (49 % female), who were participants in the San Antonio Family Assessment of Metabolic Risk Indicators in Youth (SAFARI) study. These children are offspring or biological relatives of adult participants from three well-established Mexican American family studies in San Antonio, Texas, at increased risk of type 2 diabetes. MS was defined as ≥ 3 abnormalities among 6 MSC measures: waist circumference, systolic and/or diastolic blood pressure, fasting insulin, triglycerides, HDL-cholesterol, and fasting and/or 2-h OGTT glucose. Genetic analyses of MS, number of MSCs (MSC-N), MS factors, and bivariate MS traits were performed. Overweight/obesity (53 %), pre-diabetes (13 %), acanthosis nigricans (33 %), and MS (19 %) were strikingly prevalent, as were MS components, including abdominal adiposity (32 %) and low HDL-cholesterol (32 %). Factor analysis of MS traits yielded three constructs: adipo-insulin-lipid, blood pressure, and glucose factors, and their factor scores were highly heritable. MS itself exhibited 68 % heritability. MSC-N showed strong positive genetic correlations with obesity, insulin resistance, inflammation, and acanthosis nigricans, and negative genetic correlation with physical fitness. MS trait pairs exhibited strong genetic and/or environmental correlations. These findings highlight the complex genetic architecture of MS/MSCs in MA children, and underscore the need for early screening and intervention to prevent chronic sequelae in this vulnerable pediatric population. PMID:23736306

  8. 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. PMID:26231222

  9. 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

  10. The High-Density Lipoprotein Puzzle: Why Classic Epidemiology, Genetic Epidemiology, and Clinical Trials Conflict?

    PubMed

    Rosenson, Robert S

    2016-05-01

    Classical epidemiology has established the incremental contribution of the high-density lipoprotein (HDL) cholesterol measure in the assessment of atherosclerotic cardiovascular disease risk; yet, genetic epidemiology does not support a causal relationship between HDL cholesterol and the future risk of myocardial infarction. Therapeutic interventions directed toward cholesterol loading of the HDL particle have been based on epidemiological studies that have established HDL cholesterol as a biomarker of atherosclerotic cardiovascular risk. However, therapeutic interventions such as niacin, cholesteryl ester transfer protein inhibitors increase HDL cholesterol in patients treated with statins, but have repeatedly failed to reduce cardiovascular events. Statin therapy interferes with ATP-binding cassette transporter-mediated macrophage cholesterol efflux via miR33 and thus may diminish certain HDL functional properties. Unraveling the HDL puzzle will require continued technical advances in the characterization and quantification of multiple HDL subclasses and their functional properties. Key mechanistic criteria for clinical outcomes trials with HDL-based therapies include formation of HDL subclasses that improve the efficiency of macrophage cholesterol efflux and compositional changes in the proteome and lipidome of the HDL particle that are associated with improved antioxidant and anti-inflammatory properties. These measures require validation in genetic studies and clinical trials of HDL-based therapies on the background of statins. PMID:26966281

  11. 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

  12. 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

  13. 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

  14. Principles of study design in environmental epidemiology.

    PubMed Central

    Morgenstern, H; Thomas, D

    1993-01-01

    This paper discusses the principles of study design and related methodologic issues in environmental epidemiology. Emphasis is given to studies aimed at evaluating causal hypotheses regarding exposures to suspected health hazards. Following background sections on the quantitative objectives and methods of population-based research, we present the major types of observational designs used in environmental epidemiology: first, the three basic designs involving the individual as the unit of analysis (i.e., cohort, cross-sectional, and case-control studies) and a brief discussion of genetic studies for assessing gene-environment interactions; second, various ecologic designs involving the group or region as the unit of analysis. Ecologic designs are given special emphasis in this paper because of our lack of resources or inability to accurately measure environmental exposures in large numbers of individuals. The paper concludes with a section highlighting current design issues in environmental epidemiology and several recommendations for future work. PMID:8206038

  15. A Systematic Bayesian Integration of Epidemiological and Genetic Data

    PubMed Central

    Lau, Max S. Y.; Marion, Glenn; Streftaris, George; Gibson, Gavin

    2015-01-01

    Genetic sequence data on pathogens have great potential to inform inference of their transmission dynamics ultimately leading to better disease control. Where genetic change and disease transmission occur on comparable timescales additional information can be inferred via the joint analysis of such genetic sequence data and epidemiological observations based on clinical symptoms and diagnostic tests. Although recently introduced approaches represent substantial progress, for computational reasons they approximate genuine joint inference of disease dynamics and genetic change in the pathogen population, capturing partially the joint epidemiological-evolutionary dynamics. Improved methods are needed to fully integrate such genetic data with epidemiological observations, for achieving a more robust inference of the transmission tree and other key epidemiological parameters such as latent periods. Here, building on current literature, a novel Bayesian framework is proposed that infers simultaneously and explicitly the transmission tree and unobserved transmitted pathogen sequences. Our framework facilitates the use of realistic likelihood functions and enables systematic and genuine joint inference of the epidemiological-evolutionary process from partially observed outbreaks. Using simulated data it is shown that this approach is able to infer accurately joint epidemiological-evolutionary dynamics, even when pathogen sequences and epidemiological data are incomplete, and when sequences are available for only a fraction of exposures. These results also characterise and quantify the value of incomplete and partial sequence data, which has important implications for sampling design, and demonstrate the abilities of the introduced method to identify multiple clusters within an outbreak. The framework is used to analyse an outbreak of foot-and-mouth disease in the UK, enhancing current understanding of its transmission dynamics and evolutionary process. PMID:26599399

  16. How to assess epidemiological studies

    PubMed Central

    Zaccai, J

    2004-01-01

    Assessing the quality of an epidemiological study equates to assessing whether the inferences drawn from it are warranted when account is taken of the methods, the representativeness of the study sample, and the nature of the population from which it is drawn. Bias, confounding, and chance can threaten the quality of an epidemiological study at all its phases. Nevertheless, their presence does not necessarily imply that a study should be disregarded. The reader must first balance any of these threats or missing information with their potential impact on the conclusions of the report. PMID:15016934

  17. Genetic Epidemiology and Insights into Interactive Genetic and Environmental Effects in Autism Spectrum Disorders

    PubMed Central

    Kim, Young Shin; Leventhal, Bennett L.

    2014-01-01

    Understanding the pathogenesis of Neurodevelopmental Disorders (NDDs) has proven to be challenging. Using Autism Spectrum Disorder (ASD) as a paradigmatic NDD, this paper reviews the existing literature on the etiologic substrates of ASD and explores how genetic epidemiology approaches including gene-environment interactions (GxE) can play roles in identifying factors associated with ASD etiology. New genetic and bioinformatics strategies have yielded important clues to ASD genetic substrates. Next steps for understanding ASD pathogenesis require significant effort to focus on how genes and environment interact with one another in typical development and its perturbations. Along with larger sample sizes, future study designs should include sample ascertainment that is epidemiologic and population-based to capture the entire ASD spectrum with both categorical and dimensional phenotypic characterization, environmental measurement with accuracy, validity and biomarkers, statistical methods to address population stratification, multiple comparisons and GxE of rare variants, animal models to test hypotheses and, new methods to broaden the capacity to search for GxE, including genome-wide and environment-wide association studies, precise estimation of heritability using dense genetic markers and consideration of GxE both as the disease cause and a disease course modifier. While examination of GxE appears to be a daunting task, tremendous recent progress in gene discovery opens new horizons for advancing our understanding the role of GxE in the pathogenesis of, and ultimately identifying the causes, treatments and even prevention for ASD and other NDDs. PMID:25483344

  18. 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

  19. Using Epidemiological Models and Genetic Selection to Identify Theoretical Opportunities to Reduce Disease Impact

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Selection for disease resistance is a contemporary topic with developing approaches for genetic improvement. Merging the sciences of genetic selection and epidemiology is essential to identify selection schemes to enhance disease resistance. Epidemiological models can identify theoretical opportuni...

  20. Impairment of Colour Vision in Diabetes with No Retinopathy: Sankara Nethralaya Diabetic Retinopathy Epidemiology and Molecular Genetics Study (SNDREAMS- II, Report 3)

    PubMed Central

    Gella, Laxmi; Raman, Rajiv; Kulothungan, Vaitheeswaran; Pal, Swakshyar Saumya; Ganesan, Suganeswari; Sharma, Tarun

    2015-01-01

    Purpose To assess impairment of colour vision in type 2 diabetics with no diabetic retinopathy and elucidate associated risk factors in a population-based cross-sectional study. Methods This is part of Sankara Nethralaya Diabetic Retinopathy Epidemiology and Molecular-genetics Study (SN-DREAMS II) which was conducted between 2007–2010. FM 100 hue-test was performed in 253 subjects with no clinical evidence of diabetic retinopathy. All subjects underwent detailed ophthalmic evaluation including cataract grading using LOCS III and 45° 4-field stereoscopic fundus photography. Various ocular and systemic risk factors for impairment of colour vision (ICV) were assessed in subjects with diabetes but no retinopathy. P value of < 0.05 was considered statistically significant. Results The mean age of the study sample was 57.08 ± 9.21 (range: 44–86 years). Gender adjusted prevalence of ICV among subjects with diabetes with no retinopathy was 39.5% (CI: 33.5–45.5). The mean total error score in the study sample was 197.77 ± 100 (range: 19–583). The risk factors for ICV in the study were women OR: 1.79 (1.00–3.18), increased resting heart rate OR: 1.04 (1.01–1.07) and increased intraocular pressure OR: 1.12 (1.00–1.24). Significant protective factor was serum high-density lipoprotein OR: 0.96 (0.93–0.99). Conclusions Acquired ICV is an early indicator of neurodegenerative changes in the retina. ICV found in diabetic subjects without retinopathy may be of non-vascular etiology. PMID:26053017

  1. 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

  2. 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

  3. [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

  4. Genetic epidemiology and insights into interactive genetic and environmental effects in autism spectrum disorders.

    PubMed

    Kim, Young Shin; Leventhal, Bennett L

    2015-01-01

    Understanding the pathogenesis of neurodevelopmental disorders has proven to be challenging. Using autism spectrum disorder (ASD) as a paradigmatic neurodevelopmental disorder, this article reviews the existing literature on the etiological substrates of ASD and explores how genetic epidemiology approaches including gene-environment interactions (G×E) can play a role in identifying factors associated with ASD etiology. New genetic and bioinformatics strategies have yielded important clues to ASD genetic substrates. The next steps for understanding ASD pathogenesis require significant effort to focus on how genes and environment interact with one another in typical development and its perturbations. Along with larger sample sizes, future study designs should include sample ascertainment that is epidemiologic and population-based to capture the entire ASD spectrum with both categorical and dimensional phenotypic characterization; environmental measurements with accuracy, validity, and biomarkers; statistical methods to address population stratification, multiple comparisons, and G×E of rare variants; animal models to test hypotheses; and new methods to broaden the capacity to search for G×E, including genome-wide and environment-wide association studies, precise estimation of heritability using dense genetic markers, and consideration of G×E both as the disease cause and a disease course modifier. Although examination of G×E appears to be a daunting task, tremendous recent progress in gene discovery has opened new horizons for advancing our understanding of the role of G×E in the pathogenesis of ASD and ultimately identifying the causes, treatments, and even preventive measures for ASD and other neurodevelopmental disorders. PMID:25483344

  5. Epidemiology and genetic aspects of multiple sclerosis in India

    PubMed Central

    Bhatia, Rohit; Bali, Prerna; Chaudhari, Rima M

    2015-01-01

    Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system with a complex pathophysiology. Considered a rare disease in India in the past, studies over time suggest an increase in subjects with MS in India, although the observations are limited by the lack of formally conducted epidemiological studies and the absence of a nationwide registry. The current World Health Organization (WHO) Multiple Sclerosis International Federation (MSIF) “Atlas of MS” 2013 estimates a prevalence rate of 5-20 per 100,000, which also seems an underestimate. Although there have been reports of phenotypic differences between MS in Indians and the Western counterparts, recent studies report a reasonable similarity in disease types and characteristics. A few studies on the genetics of MS have been reported, including human leukocyte antigen (HLA) associations and non-major histopathology complex (MHC) disease loci. The current review discusses the pivotal studies of the past, newer observations on MS from India, and the need for a national registry. PMID:26538851

  6. 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

  7. 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…

  8. 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

  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. [Computerization of data collection in epidemiological studies].

    PubMed

    Galasso, R; Celentano, E

    1992-01-01

    Data collected in epidemiological studies on large cohorts need to be evaluated through the organization of a specific computer laboratory in order to make all procedures simple and fast. This paper describes the basic elements composing a computer laboratory and discusses its implementation in epidemiological investigations. PMID:1492737

  11. Epidemiological, clinical, and genetic characteristics of early-onset parkinsonism.

    PubMed

    Schrag, Anette; Schott, Jonathan M

    2006-04-01

    In this review we discuss the epidemiological, clinical, and genetic characteristics of early-onset parkinsonism, defined as parkinsonism starting before age 40 (sometimes 50) years. Juvenile parkinsonism is very rare and is the result of various secondary or genetic causes. In patients with onset at or above age 21 years, secondary causes require exclusion but are rare; most cases with a fairly pure parkinsonian syndrome (eg, young-onset Parkinson's disease; YOPD) are due to typical Lewy-body Parkinson's disease or, less commonly, genetic causes. In comparison with patients with late-onset disease, most patients with YOPD progress more slowly in terms of motor features and have a longer disease course with preservation of cognitive function, but typically develop motor fluctuations and dyskinesias earlier. Patients with YOPD generally experience a greater effect in their lives than those with late onset, with poorer social adjustment, higher rates of depression, and lower quality of life. Management of YOPD must therefore aim to maintain occupational, social, and daily functioning, while delaying or ameliorating motor complications of treatment, providing psychological support, and, where possible, preventing psychiatric complications including depression. PMID:16545752

  12. [Epidemiology of schizophrenic disorders, genetic and environmental risk factors].

    PubMed

    Szoke, Andrei

    2013-03-01

    Schizophrenia is a relatively common pathology with onset at adolescence or early adulthood, more frequent in men than women. By describing distribution of cases in different populations and the factors that influence this distribution, epidemiology contributes to our understanding of the disease. Several risk factors for schizophrenia have been uncovered both genetic and environmental. The environmental factors can act at individual level (obstetric complications, season of birth, urbanicity, childhood trauma, cannabis, migration) or at population/area levels (socio-economic level, social fragmentation and social capital, ethnic density, etc.). An integrative and dynamic model based on the "vulnerability-persistence-impairment" paradigm is useful in integrating the findings about the risk factors and their complex relationships. PMID:23687754

  13. Environmental pollutants and breast cancer: epidemiologic studies.

    PubMed

    Brody, Julia Green; Moysich, Kirsten B; Humblet, Olivier; Attfield, Kathleen R; Beehler, Gregory P; Rudel, Ruthann A

    2007-06-15

    Laboratory research has shown that numerous environmental pollutants cause mammary gland tumors in animals; are hormonally active, specifically mimicking estrogen, which is a breast cancer risk factor; or affect susceptibility of the mammary gland to carcinogenesis. An assessment of epidemiologic research on these pollutants identified in toxicologic studies can guide future research and exposure reduction aimed at prevention. The PubMed database was searched for relevant literature and systematic critical reviews were entered in a database available at URL: www.silentspring.org/sciencereview and URL: www.komen.org/environment (accessed April 10, 2007). Based on a relatively small number of studies, the evidence to date generally supports an association between breast cancer and polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) in conjunction with certain genetic polymorphisms involved in carcinogen activation and steroid hormone metabolism. Evidence regarding dioxins and organic solvents is sparse and methodologically limited but suggestive of an association. Methodologic problems include inadequate exposure assessment, a lack of access to highly exposed and unexposed populations, and a lack of preclinical markers to identify associations that may be obscured by disease latency. Among chemicals identified in toxicologic research as relevant to breast cancer, many have not been investigated in humans. The development of better exposure assessment methods is needed to fill this gap. In the interim, weaknesses in the epidemiologic literature argue for greater reliance on toxicologic studies to develop national policies to reduce chemical exposures that may be associated with breast cancer. Substantial research progress in the last 5 years suggests that the investigation of environmental pollutants will lead to strategies to reduce breast cancer risk. PMID:17503436

  14. 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

  15. A Bayesian Inference Framework to Reconstruct Transmission Trees Using Epidemiological and Genetic Data

    PubMed Central

    Morelli, Marco J.; Thébaud, Gaël; Chadœuf, Joël; King, Donald P.; Haydon, Daniel T.; Soubeyrand, Samuel

    2012-01-01

    The accurate identification of the route of transmission taken by an infectious agent through a host population is critical to understanding its epidemiology and informing measures for its control. However, reconstruction of transmission routes during an epidemic is often an underdetermined problem: data about the location and timings of infections can be incomplete, inaccurate, and compatible with a large number of different transmission scenarios. For fast-evolving pathogens like RNA viruses, inference can be strengthened by using genetic data, nowadays easily and affordably generated. However, significant statistical challenges remain to be overcome in the full integration of these different data types if transmission trees are to be reliably estimated. We present here a framework leading to a bayesian inference scheme that combines genetic and epidemiological data, able to reconstruct most likely transmission patterns and infection dates. After testing our approach with simulated data, we apply the method to two UK epidemics of Foot-and-Mouth Disease Virus (FMDV): the 2007 outbreak, and a subset of the large 2001 epidemic. In the first case, we are able to confirm the role of a specific premise as the link between the two phases of the epidemics, while transmissions more densely clustered in space and time remain harder to resolve. When we consider data collected from the 2001 epidemic during a time of national emergency, our inference scheme robustly infers transmission chains, and uncovers the presence of undetected premises, thus providing a useful tool for epidemiological studies in real time. The generation of genetic data is becoming routine in epidemiological investigations, but the development of analytical tools maximizing the value of these data remains a priority. Our method, while applied here in the context of FMDV, is general and with slight modification can be used in any situation where both spatiotemporal and genetic data are available. PMID

  16. The epidemiology of eating disorders: genetic, environmental, and societal factors

    PubMed Central

    Mitchison, Deborah; Hay, Phillipa J

    2014-01-01

    Background The aim of this review was to summarize the literature to date regarding the sociodemographic, environmental, and genetic correlates of eating disorders (EDs) in adults. Method A keyword search was entered into Scopus (SciVerse, Elsevier) to identify relevant articles published in English up until June 2013. Articles were assessed against a range of a priori inclusion and exclusion criteria. Results A total of 149 full-text articles were found to be eligible for the review and included 86 articles with data on sociodemographic correlates, 57 on environmental correlates, and 13 on genetic correlates. Female sex, younger age, sexual and physical abuse, participation in esthetic or weight-oriented sports, and heritability were found to be most consistently associated with higher ED prevalence and incidence. Conversely, ethnicity, socioeconomic status, education, and urbanicity did not appear to have strong associations with ED epidemiology. Conclusion More community-based research, with an equal representation of males, needs to be conducted to confirm the current findings and provide evidence for emerging factors that may be related to EDs. PMID:24728136

  17. Epidemiology, major risk factors and genetic predisposition for breast cancer in the Pakistani population.

    PubMed

    Shaukat, Uzma; Ismail, Muhammad; Mehmood, Nasir

    2013-01-01

    Occurrence of breast cancer is related to genetic as well as cultural, environmental and life-style factors. Variations in diversity of these factors among different ethnic groups and geographical areas emphasize the immense need for studies in all racial-ethnic populations. The incidence of breast cancer in Pakistan is highest in Asians after Jews in Israel and 2.5 times higher than that in neighboring countries like Iran and India, accounting for 34.6% of female cancers. The Pakistani population is deficient in information regarding breast cancer etiology and epidemiology, but efforts done so far had suggested consanguinity as a major risk factor for frequent mutations leading to breast cancer and has also shed light on genetic origins in different ethnic groups within Pakistan. World-wide research efforts on different ethnicities have enhanced our understanding of genetic predisposition to breast cancer but despite these discoveries, 75% of the familial risk of breast cancer remains unexplained, highlighting the fact that the majority of breast cancer susceptibility genes remain unidentified. For this purpose Pakistani population provides a strong genetic pool to elucidate the genetic etiology of breast cancer because of cousin marriages. In this review, we describe the known breast cancer predisposition factors found in the local Pakistani population and the epidemiological research work done to emphasize the importance of exploring factors/variants contributing to breast cance, in order to prevent, cure and decrease its incidence in our country. PMID:24289553

  18. Clustered Environments and Randomized Genes: A Fundamental Distinction between Conventional and Genetic Epidemiology

    PubMed Central

    Smith, George Davey; Lawlor, Debbie A; Harbord, Roger; Timpson, Nic; Day, Ian; Ebrahim, Shah

    2007-01-01

    Background In conventional epidemiology confounding of the exposure of interest with lifestyle or socioeconomic factors, and reverse causation whereby disease status influences exposure rather than vice versa, may invalidate causal interpretations of observed associations. Conversely, genetic variants should not be related to the confounding factors that distort associations in conventional observational epidemiological studies. Furthermore, disease onset will not influence genotype. Therefore, it has been suggested that genetic variants that are known to be associated with a modifiable (nongenetic) risk factor can be used to help determine the causal effect of this modifiable risk factor on disease outcomes. This approach, mendelian randomization, is increasingly being applied within epidemiological studies. However, there is debate about the underlying premise that associations between genotypes and disease outcomes are not confounded by other risk factors. We examined the extent to which genetic variants, on the one hand, and nongenetic environmental exposures or phenotypic characteristics on the other, tend to be associated with each other, to assess the degree of confounding that would exist in conventional epidemiological studies compared with mendelian randomization studies. Methods and Findings We estimated pairwise correlations between nongenetic baseline variables and genetic variables in a cross-sectional study comparing the number of correlations that were statistically significant at the 5%, 1%, and 0.01% level (α = 0.05, 0.01, and 0.0001, respectively) with the number expected by chance if all variables were in fact uncorrelated, using a two-sided binomial exact test. We demonstrate that behavioural, socioeconomic, and physiological factors are strongly interrelated, with 45% of all possible pairwise associations between 96 nongenetic characteristics (n = 4,560 correlations) being significant at the p < 0.01 level (the ratio of observed to expected

  19. Sibling recurrence and the genetic epidemiology of autism

    PubMed Central

    Constantino, John N.; Zhang, Yi; Frazier, Thomas; Abbacchi, Anna M.; Law, Paul

    2010-01-01

    Objective Although the symptoms of autism exhibit quantitative distributions in nature, estimates of recurrence risk in families have never previously considered or incorporated quantitative characterization of the autistic phenotype among siblings. Method We report the results of quantitative characterization of 2,920 children from 1,235 families participating in a national volunteer register who met the criteria of having at least one child clinically-affected by an autism spectrum disorder (ASD) and at least one full biological sibling. Results The occurrence of a traditionally-defined ASD in an additional child occurred in 10.9% of the families. An additional 20% of non-ASD-affected siblings had a history of language delay, half of whom had exhibited autistic qualities of speech. Quantitative characterization using the Social Responsiveness Scale (SRS) supported previously-reported aggregation of a wide range of subclinical (quantitative) autistic traits among otherwise unaffected children in multiple-incidence families, and a relative absence of quantitative autistic traits among siblings in single-incidence autism families. Girls whose standardized severity ratings fell above a first percentile severity threshold (relative to the general population distribution) were significantly less likely to have elicited community diagnoses than their male counterparts. Conclusions These data suggest that, depending on how it is defined, sibling recurrence in ASD may exceed previously-published estimates, and varies as a function of family type. The results support differences in mechanisms of genetic transmission between simplex and multiplex autism, and advance current understanding of the genetic epidemiology of autism. PMID:20889652

  20. Genetic Epidemiology and Nonsyndromic Structural Birth Defects: From Candidate Genes to Epigenetics

    PubMed Central

    Hobbs, Charlotte A.; Chowdhury, Shimul; Cleves, Mario A.; Erickson, Stephen; MacLeod, Stewart L.; Shaw, Gary M.; Shete, Sanjay J.; Witte, John S.; Tycko, Benjamin

    2014-01-01

    Birth defects are a leading cause of infant morbidity and mortality worldwide. The vast majority of birth defects are nonsyndromic, and although their etiologies remain mostly unknown, evidence supports the hypothesis that they result from the complex interaction of genetic, epigenetic, environmental, and lifestyle factors. Since our last review published in 2002 describing the basic tools of genetic epidemiology used to study nonsyndromic structural birth defects, many new approaches have become available and have been used with varying success. Through rapid advances in genomic technologies, investigators are now able to interrogate large portions of the genome at a fraction of previous costs. With next generation sequencing (NGS), research has progressed from assessing a small percentage of single nucleotide polymorphisms (SNPs) to assessing the entire human protein-coding repertoire (exome) – an approach that is starting to uncover rare but informative mutations associated with nonsyndromic birth defects. Here we report on the current state of genetic epidemiology of birth defects and comment on future challenges and opportunities. We consider issues of study design, and we discuss common variant approaches including candidate gene studies and genome-wide association studies (GWAS). We also discuss the complexities embedded in exploring gene-environment interactions. We complete our review by describing new and promising NGS technologies and examining how the study of epigenetic mechanisms could become the key to unraveling the complex etiologies of nonsyndromic structural birth defects. PMID:24515445

  1. Psoriasis and comorbidities. Epidemiological studies.

    PubMed

    Egeberg, Alexander

    2016-02-01

    Psoriasis is a prevalent chronic inflammatory disease whose exact aetiology is not fully understood, but both genetic and environmental factors have been implicated in the onset and progression of the disease. At the skin level, psoriasis is characterized by localized or widespread thick raised silvery-white scaling and pruritic plaques and studies have shown that psoriasis negatively affects patients' quality of life, and depression occurs more often in patients with psoriasis. However, data have shown that psoriasis is a systemic disease which affects the joints, vasculature, and other tissues as well. Indeed, approximately one-third of patients with psoriasis develop psoriatic arthritis, and patients with severe psoriasis have a shortened life expectancy. Although our knowledge of the pathogenesis of psoriasis has advanced significantly in the past decade, as have the pharmacological treatment options which are now available, several important knowledge gaps remain. Many of the proinflammatory mediators involved in psoriasis have also been implicated in some central nervous system (CNS) diseases. However, studies on associations between psoriasis and CNS diseases are scarce. Based on nationwide registry data from the entire Danish population, the present thesis examined the associations between psoriasis and certain CNS diseases. The specific objectives of this work were to investigate the independent impact of depression on the risk of cardiovascular disease (CVD) in patients with psoriasis, the relationship between psoriasis and uveitis, and the risk of incident multiple sclerosis (MS) following the onset of psoriasis, respectively. The main results were a significantly increased risk of myocardial infarction, stroke, and CVD death in patients with psoriasis during stages of acute depression. Moreover, we found a bidirectional relationship between psoriasis and uveitis, where the occurrence of either disease significantly increased the risk of the other

  2. Molecular approaches for a better understanding of the epidemiology and population genetics of Leishmania.

    PubMed

    Schönian, G; Kuhls, K; Mauricio, I L

    2011-04-01

    Molecular approaches are being used increasingly for epidemiological studies of visceral and cutaneous leishmaniases. Several molecular markers resolving genetic differences between Leishmania parasites at species and strain levels have been developed to address key epidemiological and population genetic questions. The current gold standard, multilocus enzyme typing (MLEE), needs cultured parasites and lacks discriminatory power. PCR assays identifying species directly with clinical samples have proven useful in numerous field studies. Multilocus sequence typing (MLST) is potentially the most powerful phylogenetic approach and will, most probably, replace MLEE in the future. Multilocus microsatellite typing (MLMT) is able to discriminate below the zymodeme level and seems to be the best candidate for becoming the gold standard for distinction of strains. Population genetic studies by MLMT revealed geographical and hierarchic population structure in L. tropica, L. major and the L. donovani complex. The existence of hybrids and gene flow between Leishmania populations suggests that sexual recombination is more frequent than previously thought. However, typing and analytical tools need to be further improved. Accessible databases should be created and sustained for integrating data obtained by different researchers. This would allow for global analyses and help to avoid biases in analyses due to small sample sizes. PMID:21078222

  3. Epidemiology and genetic characterization of hepatitis A virus genotype IIA.

    PubMed

    Desbois, Delphine; Couturier, Elisabeth; Mackiewicz, Vincent; Graube, Arielle; Letort, Marie-José; Dussaix, Elisabeth; Roque-Afonso, Anne-Marie

    2010-09-01

    Three hepatitis A virus (HAV) genotypes, I, II, and III, divided into subtypes A and B, infect humans. Genotype I is the most frequently reported, while genotype II is hardly ever isolated, and its genetic diversity is unknown. From 2002 to 2007, a French epidemiological survey of HAV identified 6 IIA isolates, mostly from patients who did not travel abroad. The possible African origin of IIA strains was investigated by screening the 2008 mandatory notification records of HAV infection: 171 HAV strains from travelers to West Africa and Morocco were identified. Genotyping was performed by sequencing of the VP1/2A junction in 68 available sera. Entire P1 and 5' untranslated regions of IIA strains were compared to reference sequences of other genotypes. The screening retrieved 5 imported IIA isolates. An additional autochthonous case and 2 more African cases were identified in 2008 and 2009, respectively. A total of 14 IIA isolates (8 African and 6 autochthonous) were analyzed. IIA sequences presented lower nucleotide and amino acid variability than other genotypes. The highest variability was observed in the N-terminal region of VP1, while for other genotypes the highest variability was observed at the VP1/2A junction. Phylogenetic analysis identified 2 clusters, one gathering all African and two autochthonous cases and a second including only autochthonous isolates. In conclusion, most IIA strains isolated in France are imported by travelers returning from West Africa. However, the unexplained contamination mode of autochthonous cases suggests another, still to be discovered geographical origin or a French reservoir to be explored. PMID:20592136

  4. Epidemiology and Genetic Characterization of Hepatitis A Virus Genotype IIA▿

    PubMed Central

    Desbois, Delphine; Couturier, Elisabeth; Mackiewicz, Vincent; Graube, Arielle; Letort, Marie-José; Dussaix, Elisabeth; Roque-Afonso, Anne-Marie

    2010-01-01

    Three hepatitis A virus (HAV) genotypes, I, II, and III, divided into subtypes A and B, infect humans. Genotype I is the most frequently reported, while genotype II is hardly ever isolated, and its genetic diversity is unknown. From 2002 to 2007, a French epidemiological survey of HAV identified 6 IIA isolates, mostly from patients who did not travel abroad. The possible African origin of IIA strains was investigated by screening the 2008 mandatory notification records of HAV infection: 171 HAV strains from travelers to West Africa and Morocco were identified. Genotyping was performed by sequencing of the VP1/2A junction in 68 available sera. Entire P1 and 5′ untranslated regions of IIA strains were compared to reference sequences of other genotypes. The screening retrieved 5 imported IIA isolates. An additional autochthonous case and 2 more African cases were identified in 2008 and 2009, respectively. A total of 14 IIA isolates (8 African and 6 autochthonous) were analyzed. IIA sequences presented lower nucleotide and amino acid variability than other genotypes. The highest variability was observed in the N-terminal region of VP1, while for other genotypes the highest variability was observed at the VP1/2A junction. Phylogenetic analysis identified 2 clusters, one gathering all African and two autochthonous cases and a second including only autochthonous isolates. In conclusion, most IIA strains isolated in France are imported by travelers returning from West Africa. However, the unexplained contamination mode of autochthonous cases suggests another, still to be discovered geographical origin or a French reservoir to be explored. PMID:20592136

  5. Genetic epidemiology and pharmacogenetics in irritable bowel syndrome

    PubMed Central

    Katzka, David A.

    2012-01-01

    The objectives of this review are twofold. Our first objective is to evaluate the evidence supporting a role for genetics in irritable bowel syndrome (IBS). Specific examples of the associations of genetic variation and symptoms, syndromes, and intermediate phenotypes, including neurotransmitter (serotonergic, α2-adrenergic, and cannabinoid) mechanisms, inflammatory pathways (IL-10, TNFα, GNβ3, and susceptibility loci involved in Crohn's disease), and bile acid metabolism, are explored. The second objective is to review pharmacogenetics in IBS, with the focus on cytochrome P-450 metabolism of drugs used in IBS, modulation of motor and sensory responses to serotonergic agents based on the 5-hydroxytryptamine (5-HT) transporter-linked polymorphic region (5-HTTLPR) and 5-HT3 genetic variants, responses to a nonselective cannabinoid agonist (dronabinol) based on cannabinoid receptor (CNR1) and fatty acid amide hydrolase (FAAH) variation, and responses to a bile acid (sodium chenodeoxycholate) and bile acid binding (colesevelam) based on klothoβ (KLB) and fibroblast growth factor receptor 4 (FGFR4) variation. Overall, there is limited evidence of a genetic association with IBS; the most frequently studied association is with 5-HTTLPR, and the most replicated association is with TNF superfamily member 15. Most of the pharmacogenetic associations are reported with intermediate phenotypes in relatively small trials, and confirmation in large clinical trials using validated clinical end points is still required. No published genome-wide association studies in functional gastrointestinal or motility disorders have been published. PMID:22403795

  6. IMPROVING EXPOSURE ASSESSMENT IN DBP EPIDEMIOLOGIC STUDIES

    EPA Science Inventory

    In 1997, an EPA expert panel was convened to evaluate epidemiologic studies of adverse reproductive or developmental outcomes that may be associated with drinking water DBPs. The panel recommended that further efforts be made in an existing cohort study, headed by Dr. Waller and ...

  7. The genetic epidemiology of diverticulosis and diverticular disease: Emerging evidence

    PubMed Central

    Reichert, Matthias C

    2015-01-01

    Diverticular disease (DD) is one of the most prevalent gastrointestinal disorders. The pathogenesis of diverticulosis and DD is controversially discussed. Current studies call the traditional concept of a fibre-deficient diet causing the development of diverticula into question. Data from two recent twin studies have provided conclusive evidence for a strong genetic component to diverticulosis. Although genomewide association studies have provided new insights into the polygenic architecture of human diseases, genomic research in diverticulosis and DD has just been started. This is an astonishing fact given the high morbidity and mortality of the disease, as well as the substantial economic burden on health care systems. For this review, we provide an update of the molecular pathobiology and summarise recent evidence supporting the hypothesis that distinct, yet unidentified genetic variants contribute to the development of diverticulosis and DD. PMID:26535118

  8. Implications of genetic epidemiology for the prevention of substance use disorders.

    PubMed

    Merikangas, K R; Avenevoli, S

    2000-01-01

    Despite advances in characterizing human genotypes, the complex process through which genes exert their influence limits the application of molecular genetics to human diseases. Substance use disorders are necessarily complicated by gene-environment interaction because exposure to an exogenous substance is required for their development. The methods of genetic epidemiology are specifically designed to identify sources of complexity that impede etiologic findings and prevention efforts. The goal of this paper is to illustrate the application of family study methods to identify risk factors for substance abuse and their implications for prevention. The Yale Family Study is a controlled family study of the comorbidity of substance and psychiatric disorders. The sample consists of 223 probands with substance use and/or an anxiety disorders and community controls, 1218 adult first degree relatives and spouses, and 203 offspring (ages 7-17) followed for 8 years. Results indicated familial aggregation of substance disorders in adults and children, independence of familial aggregation of alcoholism and drug dependence, and specificity of familial clustering of some drugs of abuse. Familial factors are more strongly associated with substance dependence than abuse, with an attributable risk of 55%. Premorbid psychiatric disorders--social phobia and bipolar affective disorder in adults, and depression, anxiety, conduct, and oppositional defiant disorders in children--were strongly associated with the subsequent development of substance dependence (attributable risks ranging from 44 to 86%). A family history of substance abuse and premorbid psychopathology are strongly associated with the development of substance use disorders. Implications for primary and secondary prevention are discussed. As specific genetic vulnerability markers for substance use disorders become identified, application of the tools of genetic epidemiology may be employed to identify specific environmental

  9. Genetic epidemiology of Sarcoptes scabiei (Acari: Sarcoptidae) in northern Australia.

    PubMed

    Walton, S F; Dougall, A; Pizzutto, S; Holt, D; Taplin, D; Arlian, L G; Morgan, M; Currie, B J; Kemp, D J

    2004-06-01

    Utilising three hypervariable microsatellite markers we have previously shown that scabies mites on people are genetically distinct from those on dogs in sympatric populations in northern Australia. This had important ramifications on the formulation of public health control policies. In contrast phylogenetic analyses using mitochondrial markers on scabies mites infecting multiple animal hosts elsewhere in the world could not differentiate any genetic variation between mite haplotype and host species. Here we further analyse the intra-specific relationship of Sarcoptes scabiei var. hominis with S. scabiei var. canis by using both mitochondrial DNA and an expanded nuclear microsatellite marker system. Phylogenetic studies using sequences from the mitochondrial genes coding for 16S rRNA and Cytochrome Oxidase subunit I demonstrated significant relationships between S. scabiei MtDNA haplotypes, host species and geographical location. Multi-locus genotyping using 15 microsatellite markers substantiated previous data that gene flow between scabies mite populations on human and dog hosts is extremely rare in northern Australia. These data clearly support our previous contention that control programs for human scabies in endemic areas with sympatric S. scabiei var. hominis and var. canis populations must focus on human-to-human transmission. The genetic division of dog and human derived scabies mites also has important implications in vaccine and diagnostic test development as well as the emergence and monitoring of drug resistance in S. scabiei in northern Australia. PMID:15157767

  10. 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

  11. 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

  12. 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

    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

  13. 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

  14. Environmental and Genetic Contribution to Hypertension Prevalence: Data from an Epidemiological Survey on Sardinian Genetic Isolates

    PubMed Central

    Biino, Ginevra; Parati, Gianfranco; Concas, Maria Pina; Adamo, Mauro; Angius, Andrea; Vaccargiu, Simona; Pirastu, Mario

    2013-01-01

    Background and Objectives Hypertension represents a major cause of cardiovascular morbidity and mortality worldwide but its prevalence has been shown to vary in different countries. The reasons for such differences are still matter of debate, the relative contributions given by environmental and genetic factors being still poorly defined. We estimated the current prevalence, distribution and determinants of hypertension in isolated Sardinian populations and also investigated the environmental and genetic contribution to hypertension prevalence taking advantage of the characteristics of such populations. Methods and Results An epidemiological survey with cross-sectional design was carried out measuring blood pressure in 9845 inhabitants of 10 villages of Ogliastra region between 2002 and 2008. Regression analysis for assessing blood pressure determinants and variance component models for estimating heritability were performed. Overall 38.8% of this population had hypertension, its prevalence varying significantly by age, sex and among villages taking into account age and sex structure of their population. About 50% of hypertensives had prior cardiovascular disease. High blood pressure was independently associated with age, obesity related factors, heart rate, total cholesterol, alcohol consumption, low education and smoking status, all these factors contributing more in women than in men. Heritability was 27% for diastolic and 36% for systolic blood pressure, its contribution being significantly higher in men (57%) than in women (46%). Finally, the genetic correlation between systolic and diastolic blood pressure was 0.74, indicating incomplete pleiotropy. Conclusion Genetic factors involved in the expression of blood pressure traits account for about 30% of the phenotypic variance, but seem to play a larger role in men; comorbidities and environmental factors remain of predominant importance, but seem to contribute much more in women. PMID:23527229

  15. 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...

  16. [Toward a more rational field-genetic epidemiology].

    PubMed

    Koizumi, Akio

    2010-01-01

    Genetic dissection of diseases is one of the epoch-making achievements in modern medicine. Positional cloning is a key method to isolate disease-related genes. For positional cloning, there are two conventional methods: family-based studies and case-control studies. In this review, I would like to describe several family-based studies on single gene diseases which I had conducted including those of Akita diabetic mice, systemic carnitine deficiency and Hartnup disease. The study of systemic carnitine deficiency underscored a potential power of the "Carrier state." Furthermore, cultural and public health practices in Japan such as preservation of umbilical cords and mother and child passbooks enabled us to conduct linkage analysis even 20 years after the deaths of affected patients in Hartnup disease. For multifactorial diseases, I present three family-based studies: intracranial aneurysm, moyamoya and arteriovenous malformation. Finally, I discuss on theoretical issues concerning the relationship among odds ratio, phenocopy rate and penetrance by formulating a single-locus dominant association model. Analysis of the model predicted a notion that a large odds ratio facilitates familial clustering of multifactorial diseases and vice versa is the case. Furthermore, the analysis predicted that genetic markers for screening should have odds ratio >/= eight to maintain similar qualities commonly required for clinical tests. Collectively, the analysis predicted a two-stage study design composed of linkage analysis based on a family study and subsequent replication by a case-control association study is more rational than the currently used two-independent case-control design. This newly proposed method is expected to provide polymorphisms, which have large odds ratios, requiring only minimum research budgets. PMID:20134107

  17. [Mendelian randomisation - a genetic approach to an epidemiological method].

    PubMed

    Stensrud, Mats Julius

    2016-06-01

    BACKGROUND Genetic information is becoming more easily available, and rapid progress is being made in developing methods of illuminating issues of interest. Mendelian randomisation makes it possible to study causes of disease using observational data. The name refers to the random distribution of gene variants in meiosis. The methodology makes use of genes that influence a risk factor for a disease, without influencing the disease itself. In this review article I explain the principles behind Mendelian randomisation and present the areas of application for this methodology.MATERIAL AND METHOD Methodology articles describing Mendelian randomisation were reviewed. The articles were found through a search in PubMed with the combination «mendelian randomization» OR «mendelian randomisation», and a search in McMaster Plus with the combination «mendelian randomization». A total of 15 methodology articles were read in full text. Methodology articles were supplemented by clinical studies found in the PubMed search.RESULTS In contrast to traditional observational studies, Mendelian randomisation studies are not affected by two important sources of error: conventional confounding variables and reverse causation. Mendelian randomisation is therefore a promising tool for studying causality. Mendelian randomisation studies have already provided valuable knowledge on the risk factors for a wide range of diseases. It is nevertheless important to be aware of the limitations of the methodology. As a result of the rapid developments in genetics research, Mendelian randomisation will probably be widely used in future years.INTERPRETATION If Mendelian randomisation studies are conducted correctly, they may help to reveal both modifiable and non-modifiable causes of disease. PMID:27325033

  18. 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…

  19. Dyslipidemia and dementia: current epidemiology, genetic evidence and mechanisms behind the associations

    PubMed Central

    Reitz, Christiane

    2013-01-01

    The role of cholesterol in the etiology of Alzheimer’s disease (AD) is still controversial. Some studies aiming to explore the association between lipids and/or lipid lowering treatment and AD indicate a harmful effect of dyslipidemia and a beneficial effect of statin therapy on AD risk. The findings are supported by genetic linkage and association studies that have clearly identified several genes involved in cholesterol metabolism or transport as AD susceptibility genes, including Apolipoprotein E (APOE), Apolipoprotein J (APOJ, CLU) and the sortilin-related receptor (SORL1). Functional cell biology studies support a critical involvement of lipid raft cholesterol in the modulation of AbetaPP processing by β- and γ-secretase resulting in altered Aβ production. Contradictory evidence comes from epidemiological studies showing no or controversial association between dyslipidemia and AD risk, cell biology studies suggesting that there is little exchange between circulating and brain cholesterol, that increased membrane cholesterol is protective by inhibiting loss of membrane integrity through amyloid cytotoxicity, and that cellular cholesterol inhibits co-localization of BACE1 and AbetaPP in non-raft membrane domains and thereby increasing generation of plasmin, an Aβ-degrading enzyme. The aim of this review is to summarize the findings of epidemiologic and cell biologic studies aiming to elucidate the role of cholesterol in AD etiology. PMID:21965313

  20. Exploration of the Genetic Epidemiology of Asthma: A Review, with a Focus on Prevalence in Children and Adolescents in the Caribbean

    PubMed Central

    Mohan, A; Roberto, AJ; Whitehill, BC; Mohan, A; Kumar, A

    2014-01-01

    ABSTRACT Asthma is a chronic disease caused by the inflammation of the main air passages of the lungs. This paper outlines a review of the published literature on asthma. While a few studies show a trend of rising asthma cases in the Caribbean region, even fewer have explored the genetic epidemiological factors of asthma. This is a literature review that seeks to sum the body of knowledge on the epidemiology of asthma. Specifically, the major objective of the literature review is to provide a unified information base on the current state of factors involved in the genetic epidemiology of asthma. The review is a simple, yet detailed summary of the literature sources and their methodology and findings on the genetic epidemiology of asthma. Further, it seeks to direct this effort to the Caribbean region. The paper then reviews a summarized and synthesized collection of the body of previous research. Of specific interest are peer-reviewed sources that have been published in recent times. The paper provides more recent insight and recapitulates on the previous research, while tracing the intellectual progress on the debate. Where possible, reviewing and discussing the results of the previous literature, this review singles out the gaps and potential future research directions for studying the genetic epidemiology of asthma. Overall, we hope to contribute to a more synthesized knowledge and improved understanding of the previous literature and future potential direction of genetic and epidemiological asthma research. PMID:25867554

  1. 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

  2. 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.

  3. Epidemiology and genetic relatedness of measles virus infection in Uttar Pradesh, India, during 2009-2010.

    PubMed

    Shakya, Akhalesh Kumar; Shukla, Vibha; Maan, Harjeet Singh; Dhole, T N

    2012-01-28

    Measles surveillance and epidemiological investigation are beneficial tools for genetic analysis and documentation of the interruption of transmission of endemic measles. In this study, areas of Uttar Pradesh, India, associated with measles outbreaks were investigated. Random blood and urine samples were collected from clinically defined cases. The cases were investigated through extensive house-to house surveys. The cases were diagnosed clinically and serologically, and through genotyping of the virus. All of the cases were found to be serologically positive for measles. In the studied population, a 1.9% case fatality rate and an overall 16% attack rate of measles virus were found. Out of 10 outbreak areas, the measles virus D8 genotype was found in nine, and the D8 and A genotypes were found in the remaining area. This study calls for an improved surveillance system and intensive characterization of genotypes in circulation for the measles elimination program in India. PMID:22286750

  4. 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

  5. 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

  6. 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

  7. 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

  8. 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

  9. 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

  10. 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

  11. The relationship between schizophrenia and rheumatoid arthritis revisited: Genetic and epidemiological analyses

    PubMed Central

    Breen, Gerome; Farmer, Anne; McGuffin, Peter; Lewis, Cathryn M

    2015-01-01

    Epidemiological studies are inconsistent on the relationship between schizophrenia (SCZ) and rheumatoid arthritis (RA). Several studies have shown that SCZ has a protective effect on RA, with RA occurring less frequently in SCZ cases than would be expected by chance, whilst other studies have failed to replicate this. We sought to test the hypothesis that this effect is due to a protective effect of SCZ risk alleles on RA onset. We first reviewed the literature on the comorbidity of RA and SCZ and performed a meta‐analysis. We then used polygenic risk scoring in an RA case control study in order to investigate the contribution of SCZ risk alleles to RA risk. Meta‐analysis across studies over the past half‐century showed that prevalence of RA in SCZ cases was significantly reduced (OR = 0.48, 95% CI: 0.34–0.67, p  < 0.0001). The relationship between SCZ genetic risk and RA status was weak. Polygenic risk of SCZ explained a small (0.1%) and non‐significant (p = 0.085) proportion of variance in RA case control status. This relationship was nominally positive, with RA cases carrying more SCZ risk alleles than controls. The current findings do not support the assertion that the relationship between RA and SCZ is explained by genetic factors, which appear to have little or no effect. The protective effect of SCZ on RA may be due to environmental factors, such as an anti‐inflammatory effect of anti‐psychotic medication or merely due to confounding limitations in study designs. © 2015 The Authors. American Journal of Medical Genetics Part B: Neuropsychiatric Genetics published by Wiley Periodicals, Inc. PMID:25656077

  12. [Molecular epidemiology of imported malaria in Italy: the use of genetic markers and in vitro sensitivity test in a study of chloroquine resistance in Plasmodium falciparum].

    PubMed

    Menegon, Michela; Sannella, Anna Rosa; Severini, Carlo; Paglia, Maria Grazia; Matteelli, Alberto; Caramello, Pietro; Severini, Francesco; Taramelli, Donatella; Majori, Giancarlo

    2006-01-01

    The emergence of Plasmodium falciparum drug-resistance, especially chloroquine resistance, represents one of the main obstacles to the control of malaria. Several studies have shown that in P. falciparum the mechanism of chloroquine resistance is linked to specific point mutations in the pfcrt gene of the parasite. In the present study we have analyzed 120 Italian imported malaria cases to evaluate the prevalence of 76T and 220S mutantions in the pfcrt gene. Moreover, the correlation between the presence of pfcrt point mutations and in vitro chloroquine resistance has been evaluated on 25 plasmodial isolates. The results showed a high prevalence of the pfcrt point mutations in isolates analyzed and a significant association between point mutations and in vitro chloroquine resistance. Molecular screening on imported malaria cases can be a useful tool to be employed in surveillance activity and also in monitoring the development and spread of drug resistance in endemic areas. PMID:17033142

  13. 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

  14. 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

  15. 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. PMID:21029772

  16. 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

  17. 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

  18. Genetic Variants Associated with Breast Cancer Risk: Comprehensive Field Synopsis, Meta-Analysis, and Epidemiologic Evidence

    PubMed Central

    Zhang, Ben; Beeghly-Fadiel, Alicia; Long, Jirong; Zheng, Wei

    2011-01-01

    SUMMARY Background Over 1,000 reports have been published during the past two decades on associations between genetic variants in candidate genes and breast cancer risk. Results have been generally inconsistent. We conducted literature searches and meta-analyses to provide a field synopsis of the current understanding of the genetic architecture of breast cancer risk. Methods Systematic literature searches for candidate gene association studies of breast cancer risk were conducted in two stages using PubMed on or before February 28, 2010. A total of 24,500 publications were identified, of which, 1,059 were deemed eligible for inclusion. Meta-analyses were conducted for 279 genetic variants in 128 candidate genes or chromosomal loci that had a minimum of three data sources available. Variants with significant associations by meta-analysis were assessed using the Venice criteria and scored as having strong, moderate, or weak cumulative evidence for an association with breast cancer risk. Findings Fifty-one variants in 40 genes showed statistically significant associations with breast cancer risk. Cumulative epidemiologic evidence for an association with breast cancer risk was graded as strong for 10 variants in six genes (ATM, CASP8, CHEK2, CTLA4, NBN, and TP53), moderate for four variants in four genes (ATM, CYP19A1, TERT, and XRCC3), and weak for 37 additional variants. Additionally, in meta-analyses that included a minimum of 10,000 cases and 10,000 controls, convincing evidence of no association with breast cancer risk was identified for 45 variants in 37 genes. Interpretation While most genetic variants evaluated in previous candidate gene studies showed no association with breast cancer risk in meta-analyses, 14 variants in 9 genes were found to have moderate to strong evidence for an association with breast cancer risk. Further evaluation of these variants is warranted. PMID:21514219

  19. Genetic subdivisions within Trypanosoma cruzi (Discrete Typing Units) and their relevance for molecular epidemiology and experimental evolution

    PubMed Central

    Tibayrenc, Michel

    2003-01-01

    Background This paper summarizes the main results obtained on Trypanosoma cruzi genetic diversity and population structure since this parasite became the theme of many genetic and molecular studies in the early seventies. Results T. cruzi exibits a paradigmatic pattern of long-term, clonal evolution, which has structured its natural populations into several discrete genetic subdivisions or "Discrete Typing Units" (DTU). Rare hybridization events are nevertheless detectable in natural populations and have been recently obtained in the laboratory. Conclusions The DTUs and natural clones of T. cruzi constitute relevant units for molecular epidemiology and experimental evolution. Experimental mating opens the way to an in-depth knowledge of this parasite's formal genetics. PMID:14613498

  20. 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. PMID:26161476

  1. 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

  2. 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

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

    PubMed Central

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

    1987-01-01

    This is the first report of a case-control epidemiological study on lymphomas and leukaemias occurring in Yorkshire during 1979-84. This paper deals with the results of the Hodgkin's disease analysis comprising 248 cases and 489 controls. The results indicate support for previous work with respect to small family size and past history of infectious mononucleosis. Positive observations made in a previous pilot study are also confirmed and extended with respect to associations with certain chronic skin lesions, dental anaesthesia and familial factors. Negative associations are described with respect to X-ray exposures and cigarette smoking. It is proposed that these results fit into a general hypothesis that these conditions are the result of interaction between infectious agents and altered immunity in those persons genetically predisposed. PMID:3814482

  4. 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.

  5. Possible implication of the genetic composition of the Lutzomyia longipalpis (Diptera: Psychodidae) populations in the epidemiology of the visceral leishmaniasis.

    PubMed

    Rocha, Leonardo de Souza; Falqueto, Aloisio; Dos Santos, Claudiney Biral; Grimaldi, Gabriel Júnior; Cupolillo, Elisa

    2011-09-01

    Lutzomyia longipalpis (Diptera: Psychodidae) is the principal vector of American visceral leishmaniasis. Several studies have indicated that the Lu. longipalpis population structure is complex. It has been suggested that genetic divergence caused by genetic drift, selection, or both may affect the vectorial capacity of Lu. longipalpis. However, it remains unclear whether genetic differences among Lu. longipalpis populations are directly implicated in the transmission features of visceral leishmaniasis. We evaluated the genetic composition and the patterns of genetic differentiation among Lu. longipalpis populations collected from regions with different patterns of transmission of visceral leishmaniasis by analyzing the sequence variation in the mitochondrial cytochrome b gene. Furthermore, we investigated the temporal distribution of haplotypes and compared our results with those obtained in a previous study. Our data indicate that there are differences in the haplotype composition and that there has been significant differentiation between the analyzed populations. Our results reveal that measures used to control visceral leishmaniasis might have influenced the genetic composition of the vector population. This finding raises important questions concerning the epidemiology of visceral leishmaniasis, because these differences in the genetic structures among populations of Lu. longipalpis may have implications with respect to their efficiency as vectors for visceral leishmaniasis. PMID:21936320

  6. Molecular epidemiology and genetic diversity of hepatitis B virus in Ethiopia.

    PubMed

    Hundie, Gadissa Bedada; Raj, V Stalin; Michael, Daniel Gebre; Pas, Suzan D; Osterhaus, Albert D M E; Koopmans, Marion P; Smits, Saskia L; Haagmans, Bart L

    2016-06-01

    Although hepatitis B virus (HBV) infection is hyperendemic in Ethiopia and constitutes a major public health problem, little is known about its genetic diversity, genotypes, and circulation. The aim of this study was to determine the molecular epidemiology and genetic diversity of HBV in Ethiopia, using 391 serum samples collected from HBsAg-positive blood donors living in five different geographic regions. The HBV S/pol gene was amplified, sequenced, and HBV genotypes, subgenotypes, serotypes, and major hydrophilic region (MHR) variants were determined. Phylogenetic analysis of 371 samples (95%) revealed the distribution of genotypes A (78%) and D (22%) in Ethiopia. Further phylogenetic analysis identified one subgenotype (A1) within genotype A, and 4 subgenotypes within genotype D (D1; 1.3%, D2; 55%, D4; 2.5%, and D6; 8.8%). Importantly, 24 isolates (30%) of genotype D formed a novel phylogenetic cluster, distinct from any known D subgenotypes, and two A/D recombinants. Analysis of predicted amino-acid sequences within the HBsAg revealed four serotypes: adw2 (79%), ayw1 (3.1%), ayw2 (7.8%), and ayw3 (11.6%). Subsequent examination of sequences showed that 51 HBV isolates (14%) had mutations in the MHR and 8 isolates (2.2%) in the reverse transcriptase known to confer antiviral resistance. This study provides the first description of HBV genetic diversity in Ethiopia with a predominance of subgenotypes A1 and D2, and also identified HBV isolates that could represent a novel subgenotype. Furthermore, a significant prevalence of HBsAg variants in Ethiopian population is revealed. J. Med. Virol. 88:1035-1043, 2016. © 2015 Wiley Periodicals, Inc. PMID:26629781

  7. 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

  8. Diversity, Epidemiology, and Genetics of Class D β-Lactamases▿

    PubMed Central

    Poirel, Laurent; Naas, Thierry; Nordmann, Patrice

    2010-01-01

    Class D β-lactamase-mediated resistance to β-lactams has been increasingly reported during the last decade. Those enzymes also known as oxacillinases or OXAs are widely distributed among Gram negatives. Genes encoding class D β-lactamases are known to be intrinsic in many Gram-negative rods, including Acinetobacter baumannii and Pseudomonas aeruginosa, but play a minor role in natural resistance phenotypes. The OXAs (ca. 150 variants reported so far) are characterized by an important genetic diversity and a great heterogeneity in terms of β-lactam hydrolysis spectrum. The acquired OXAs possess either a narrow spectrum or an expanded spectrum of hydrolysis, including carbapenems in several instances. Acquired class D β-lactamase genes are mostly associated to class 1 integron or to insertion sequences. PMID:19721065

  9. Molecular Epidemiology and Genetic Variation of Pathogenic Vibrio parahaemolyticus in Peru

    PubMed Central

    Gavilan, Ronnie G.; Zamudio, Maria L.; Martinez-Urtaza, Jaime

    2013-01-01

    Vibrio parahaemolyticus is a foodborne pathogen that has become a public health concern at the global scale. The epidemiological significance of V. parahaemolyticus infections in Latin America received little attention until the winter of 1997 when cases related to the pandemic clone were detected in the region, changing the epidemic dynamics of this pathogen in Peru. With the aim to assess the impact of the arrival of the pandemic clone on local populations of pathogenic V. parahaemolyticus in Peru, we investigated the population genetics and genomic variation in a complete collection of non-pandemic strains recovered from clinical sources in Peru during the pre- and post-emergence periods of the pandemic clone. A total of 56 clinical strains isolated in Peru during the period 1994 to 2007, 13 strains from Chile and 20 strains from Asia were characterized by Multilocus Sequence Typing (MLST) and checked for the presence of Variable Genomic Regions (VGRs). The emergence of O3:K6 cases in Peru implied a drastic disruption of the seasonal dynamics of infections and a shift in the serotype dominance of pathogenic V. parahaemolyticus. After the arrival of the pandemic clone, a great diversity of serovars not previously reported was detected in the country, which supports the introduction of additional populations cohabitating with the pandemic group. Moreover, the presence of genomic regions characteristic of the pandemic clone in other non-pandemic strains may represent early evidence of genetic transfer from the introduced population to the local communities. Finally, the results of this study stress the importance of population admixture, horizontal genetic transfer and homologous recombination as major events shaping the structure and diversity of pathogenic V. parahaemolyticus. PMID:23696906

  10. Epidemiologic and genetic aspects of spina bifida and other neural tube defects

    PubMed Central

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

    2011-01-01

    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 health officials to design and implement policies to prevent NTD pregnancies, and (c) individuals to take precautions to reduce the chance of having an NTD-affected pregnancy. Despite extensive research, our knowledge of the genetic etiology of human NTDs is limited. Although more than 200 small animal models with NTDs exist, most of these models do not replicate the human disease phenotype. Over a hundred candidate genes have been examined for risk association to human SB. The candidate genes studied include those important in folic acid metabolism, glucose metabolism, retinoid metabolism, and apoptosis. Many genes that regulate transcription in early embryogenesis and maintain planar cell polarity have also been tested as candidates. Additionally, genes identified through mouse models of NTDs have been explored as candidates. We do not know how many genes in the human genome may confer risk for NTDs in human. Less than 20% of the studied candidate genes have been determined to confer even a minor effect on risk association. Many studies have provided conflicting conclusions due to limitations in study design that potentially affect the power of statistical analysis. Future directions such as genomewide association studies (GWAS) and whole exome or even whole genome sequencing are discussed as possible avenues to identify genes that affect risk for human NTDs. PMID:20419766

  11. 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

  12. Mandibular Fractures in Iraq: An Epidemiological Study

    PubMed Central

    Bede, Salwan

    2014-01-01

    The purpose of this study was to evaluate the epidemiological characteristics of the mandibular fractures relating to gender, age, the etiology of injury, and the rendered treatment modalities and complications. The data of the patients who sustained mandibular fractures were retrieved and were analyzed retrospectively, and based on these data a descriptive analysis was conducted. A total of 112 patients were included in this study; the most common cause was road traffic accidents (RTAs) followed by assaults and missile injuries. The most frequently involved age group was 11 to 20 years, treatment modalities included conservative, closed reduction and indirect fixation, and open reduction and internal fixation (ORIF) in 11.6, 79.5, and 8.9% of the cases, respectively. Most of the major complications were injury related. This study showed RTAs to be the most frequent cause followed by assaults, it also showed that a high percentage of assault victims were females mainly of low socioeconomic status. Another distinguishing feature in this study was the high incidence of missile injuries in the form of bullets and blasts. Closed reduction still has an important role in the treatment of fractures of mandible especially when the necessary equipments for ORIF are not readily available. A higher complication rate was observed in patients diagnosed with multiple and comminuted fractures as well as those caused by violence in the form of missile and assault injuries. PMID:25709754

  13. Data sources: use in the epidemiologic study of medical devices.

    PubMed

    Torrence, Mary E

    2002-05-01

    Medical device epidemiology is the study of the prevalence and incidence of use, effectiveness, and adverse events associated with medical devices in a population. The identification of large data sources with medical device data provides a large population for epidemiologic studies. Two challenges in medical device epidemiology are the ability to find data on the specific device and the exposure of a patient to that device. This paper identifies data sources both from the govenment and from the private sector that can be used for epidemiologic studies of medical devices and, to a limited degree, studies of medical devices in women. Each source provides data for different types of devices and in differing specificity. The paper also discusses briefly the strengths and weaknesses of each data source. More data sources are needed to enhance the study of medical device epidemiology. Additional efforts and focus are needed to enhance the ability to study medical devices in women. PMID:12071476

  14. 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...

  15. 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

  16. 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

  17. 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...

  18. 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...

  19. 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...

  20. 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...

  1. Time series regression studies in environmental epidemiology

    PubMed Central

    Bhaskaran, Krishnan; Gasparrini, Antonio; Hajat, Shakoor; Smeeth, Liam; Armstrong, Ben

    2013-01-01

    Time series regression studies have been widely used in environmental epidemiology, notably in investigating the short-term associations between exposures such as air pollution, weather variables or pollen, and health outcomes such as mortality, myocardial infarction or disease-specific hospital admissions. Typically, for both exposure and outcome, data are available at regular time intervals (e.g. daily pollution levels and daily mortality counts) and the aim is to explore short-term associations between them. In this article, we describe the general features of time series data, and we outline the analysis process, beginning with descriptive analysis, then focusing on issues in time series regression that differ from other regression methods: modelling short-term fluctuations in the presence of seasonal and long-term patterns, dealing with time varying confounding factors and modelling delayed (‘lagged’) associations between exposure and outcome. We finish with advice on model checking and sensitivity analysis, and some common extensions to the basic model. PMID:23760528

  2. Time series regression studies in environmental epidemiology.

    PubMed

    Bhaskaran, Krishnan; Gasparrini, Antonio; Hajat, Shakoor; Smeeth, Liam; Armstrong, Ben

    2013-08-01

    Time series regression studies have been widely used in environmental epidemiology, notably in investigating the short-term associations between exposures such as air pollution, weather variables or pollen, and health outcomes such as mortality, myocardial infarction or disease-specific hospital admissions. Typically, for both exposure and outcome, data are available at regular time intervals (e.g. daily pollution levels and daily mortality counts) and the aim is to explore short-term associations between them. In this article, we describe the general features of time series data, and we outline the analysis process, beginning with descriptive analysis, then focusing on issues in time series regression that differ from other regression methods: modelling short-term fluctuations in the presence of seasonal and long-term patterns, dealing with time varying confounding factors and modelling delayed ('lagged') associations between exposure and outcome. We finish with advice on model checking and sensitivity analysis, and some common extensions to the basic model. PMID:23760528

  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. 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

  5. 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

  6. An epidemiologic approach to studying heterocyclic amines.

    PubMed

    Sinha, Rashmi

    2002-09-30

    Diets containing substantial amounts of red meat may increase the risk of colorectal, pancreatic, breast, prostate, and renal cancer. The association with red meat intake may be due to a combination of factors, such as content of fat, protein, and iron, and/or meat preparation (e.g. cooking or preserving methods). Laboratory results have shown that meats cooked at high temperatures contain heterocyclic amines (HCAs) known to be mutagenic and carcinogenic in animals. Many older epidemiologic studies of colon cancer using surrogates for HCA exposure from meat (for example, doneness level, surface browning, frying, intake of gravy) have produced suggestive but inconsistent results. These discrepancies may have resulted in part from having used dietary questionnaires that combined meat-cooking practices in ways that made the intake of HCAs difficult to estimate. Thus, over the last decade we have taken a multidisciplinary approach to investigating whether the association with red meat intake can be explained by meat-cooking practices that produce mutagens/carcinogens. To estimate intake, a database for HCAs have been developed and used in conjunction with a validated meat-cooking food frequency questionnaire (FFQ). To develop biological markers of internal exposure, a metabolic study was conducted where subjects consumed controlled amounts of meat cooked at low and high temperatures. The role of meat type, cooking methods, doneness levels, and meat-cooking mutagens were examined in case-control studies of colorectal adenomas, lung, and breast cancers using both questionnaire information and biomarkers. In a case-control study of colorectal adenomas, an increased risk was associated with a high intake of red meat. Most of this risk was due to intake of red meat cooked until well/very well done and/or by high-temperature cooking techniques such as grilling. Linking the FFQ information to HCA database, the impact several HCAs on risk was evaluated. An increased risk was

  7. 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...

  8. 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

  9. Fleshflies in the flesh: epidemiology, population genetics and control of outbreaks of traumatic myiasis in the Mediterranean Basin.

    PubMed

    Sotiraki, S; Farkas, R; Hall, M J R

    2010-11-24

    Although the damaging effects on healthy tissues of its developing larvae were first described in 1770, the fleshfly Wohlfahrtia magnifica remains a serious pest for the livestock industry. Wohlfahrtiosis, the severe myiasis caused by this fly, is a grave problem in terms of both the animal welfare and economic loss. This review highlights important aspects of the biology, pest status, epidemiology, population genetic structure, economics and control of W. magnifica and wohlfahrtiosis, with an emphasis on recent outbreaks in Greece and Morocco and fly population dynamics in the Mediterranean Basin. Potential areas for future studies on genetics, host tolerance, in vitro rearing, field behaviour and range expansion of the species are also discussed. PMID:20850931

  10. 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.

  11. Animal medical genetics: a perspective on the epidemiology and control of inherited disorders.

    PubMed

    Jolly, R D; Dittmer, K E; Blair, H T

    2016-05-01

    This perspective considers genetic disorders of domestic animal populations, in particular their epidemiology and control. Inherited disorders of animals share the same basic molecular biology as those of human beings, but they differ in their epidemiology due largely to the breed structure of the various species, human control of breeding and a greater influence of the founder effect, particularly due to extensive use of a limited number of sires, and inbreeding. Control of genetic disorders in animals is also more practical through extensive screening for disease, or heterozygous animals within defined breed populations, followed by exclusion of affected or carrier animals from breeding. This is assisted by the fact that, within a breed, many inherited monogenic disorders are associated with a single mutation. However some of the more important disorders may be inherited in a non-Mendelian manner, being influenced by multiple genes as well as environmental factors. These aspects are discussed and contrasted with similar aspects in human medical genetics. PMID:26667890

  12. Parental occupation and childhood cancer: review of epidemiologic studies.

    PubMed Central

    Savitz, D A; Chen, J H

    1990-01-01

    Parental occupational exposures might affect childhood cancer in the offspring through genetic changes in the ovum or sperm or through transplacental carcinogenesis. The 24 published epidemiologic studies of this association have all used case-control designs, with controls generally selected from birth certificates or from general population sampling. Occupational exposures were inferred from job titles on birth certificates or through interviews. A large number of occupation-cancer associations have been reported, many of which were not addressed or not confirmed in other studies. Several associations have been found with consistency: paternal exposures in hydrocarbon-associated occupations, the petroleum and chemical industries, and especially paint exposures have been associated with brain cancer; paint exposures have also been linked to leukemias. Maternal exposures have received much less attention, but studies have yielded strongly suggestive results linking a variety of occupational exposures to leukemia and brain cancer. The primary limitations in this literature are the inaccuracy inherent in assigning exposure based on job title alone and imprecision due to limited study size. Although no etiologic associations have been firmly established by these studies, the public health concerns and suggestive data warrant continued research. PMID:2272330

  13. RETROSPECTIVE EPIDEMIOLOGICAL STUDY OF DISEASE ASSOCIATED WITH WASTEWATER UTILIZATION

    EPA Science Inventory

    A retrospective epidemiological study was carried out on the association between enteric disease incidence and wastewater utilization in 79 kibbutzim (cooperative agricultural settlements) in Israel having a population of 32,672. Medical records on disease incidence were collecte...

  14. DESIGN STRATEGIES FOR EPIDEMIOLOGIC STUDIES OF ENVIRONMENTAL IMPACTS ON HEALTH

    EPA Science Inventory

    The papers describes epidemiologic designs and methods in studies of health effects of air pollution, whose implications, however, can be extended to the detection of health effects of other environmental exposures. Recent advances in measurement technology for the assessment of ...

  15. Genetic-epidemiological evidence on genes associated with HDL cholesterol levels: A systematic in-depth review

    PubMed Central

    Boes, Eva; Coassin, Stefan; Kollerits, Barbara; Heid, Iris M.; Kronenberg, Florian

    2009-01-01

    High-density lipoprotein (HDL) particles exhibit multiple antiatherogenic effects. They are key players in the reverse cholesterol transport which shuttles cholesterol from peripheral cells (e.g. macrophages) to the liver or other tissues. This complex process is thought to represent the basis for the antiatherogenic properties of HDL particles. The amount of cholesterol transported in HDL particles is measured as HDL cholesterol (HDLC) and is inversely correlated with the risk for coronary artery disease: an increase of 1 mg/dL of HDLC levels is associated with a 2% and 3% decrease of the risk for coronary artery disease in men and women, respectively. Genetically determined conditions with high HDLC levels (e.g. familial hyperalphalipoproteinemia) often coexist with longevity, and higher HDLC levels were found among healthy elderly individuals. HDLC levels are under considerable genetic control with heritability estimates of up to 80%. The identification and characterization of genetic variants associated with HDLC concentrations can provide new insights into the background of longevity. This review provides an extended overview on the current genetic-epidemiological evidence from association studies on genes involved in HDLC metabolism. It provides a path through the jungle of association studies which are sometimes confusing due to the varying and sometimes erroneous names of genetic variants, positions and directions of associations. Furthermore, it reviews the recent findings from genome-wide association studies which have identified new genes influencing HDLC levels. The yet identified genes together explain only a small amount of less than 10% of the HDLC variance, which leaves an enormous room for further yet to be identified genetic variants. This might be accomplished by large population-based genome-wide meta-analyses and by deep-sequencing approaches on the identified genes. The resulting findings will probably result in a re-drawing and extension of

  16. The Molecular Epidemiological Characteristics and Genetic Diversity of Salmonella Typhimurium in Guangdong, China, 2007–2011

    PubMed Central

    Huang, Yanhui; He, Dongmei; Li, Xiaocui; Liang, Zhaoming; Ke, Changwen

    2014-01-01

    Background Salmonella enterica serovar Typhimurium is the most important serovar associated with human salmonellosis worldwide. Here we aimed to explore the molecular epidemiology and genetic characteristics of this serovar in Guangdong, China. Methodology We evaluated the molecular epidemiology and genetic characteristics of 294 endemic Salmonella Typhimurium clinical isolates which were collected from 1977 to 2011 in Guangdong, China, and compared them with a global set of isolates of this serovar using epidemiological data and Multilocus Sequence Typing (MLST) analysis. Principal Finding The 294 isolates were assigned to 13 Sequencing types (STs) by MLST, of which ST34 and ST19 were the most common in Guangdong. All the STs were further assigned to two eBurst Groups, eBG1 and eBG138. The eBG1 was the major group endemic in Guangdong. Nucleotide and amino acid variability were comparable for all seven MLST loci. Tajima’s D test suggested positive selection in hisD and thrA genes (p<0.01), but positive selection was rejected for the five other genes (p>0.05). In addition, The Tajima’s D test within each eBG using the global set of isolates showed positive selection in eBG1 and eBG138 (p<0.05), but was rejected in eBG243 (p>0.05). We also analyzed the phylogenetic structure of Salmonella Typhimurium from worldwide sources and found that certain STs are geographically restricted. ACSSuT was the predominant multidrug resistance pattern for this serovar. The resistant profiles ACSSuTTmNaG, ACSSuTTmNa and ACSuTTmNaG seem to be specific for ST34, and ASSuTNa for ST19. Conclusion Here we presented a genotypic characterization of Salmonella Typhimurium isolates using MLST and found two major STs are endemic in Guangdong. Our analyses indicate that genetic selection may have shaped the Salmonella Typhimurium populations. However, further evaluation with additional isolates from various sources will be essential to reveal the scope of the epidemiological characteristics

  17. Epidemiological studies of plague in India

    PubMed Central

    Seal, S. C.

    1960-01-01

    Data from early in the twentieth century up to the present day indicate that Rattus rattus among rodents and Xenopsylla cheopis among fleas are the two most important elements in urban human plague infection in India, R. norvegicus playing a more minor role. The relative numbers of both these species have decreased in recent years in Bombay and Calcutta, while those of Bandicota bengalensis, which is less heavily parasitized by X. cheopis, have risen. This reduction in the numbers of the epidemiologically more important rodents and their fleas has been accompanied by a reduction in the number of human plague cases. PMID:20604076

  18. 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

  19. 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

  20. 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

  1. Usefulness of ribotyping in a molecular epidemiology study of shigellosis.

    PubMed Central

    Mendoza, M. C.; Martín, M. C.; González-Hevia, M. A.

    1996-01-01

    Ribotyping performed with six restriction endonucleases was used to study the molecular epidemiology of shigellosis in Asturias, Spain. The series included Shigella sonnei from 34 sporadic cases, 3 outbreaks and 3 reference strains, and S. Flexneri from sporadic cases and 1 reference strain. The S. sonnei strains were grouped into 5 ribotypes with Sal I, 4 with Hind III and Pvu II, 3 with Bgl II and EcoR I and 2 with Hinc II (Discriminatory Index (DI) between 0.54 and 0.14); the S. flexneri into 5 ribotypes with Sal I, Hinc II and Hind III, and 4 with the other enzymes (DI = 0.71 - 0.63). The combination of results for 2 or more enzymes facilitated and additional discrimination, the highest values in S. sonnei were for the 6 enzymes (16 types, DI = 0.91) and in S. flexneri for some combinations of 3 or more enzymes (7 types, DI = 0.81). Ribotypes with the 6 enzymes defined 16 clonal lines in S. sonnei and 7 in S. flexneri, which showed a different degree of genetic heterogeneity, and all the lines of each species falling into a different cluster. No line appeared as clearly endemic in the bowels of Asturian people. Images Fig. 1 Fig. 2 PMID:8620903

  2. Molecular epidemiological study of dengue virus type 1 in Taiwan.

    PubMed

    Hwang, Kao-Pin; Chu, Pei-Yu; Tung, Yi-Ching; Wang, Heng-Lin; Yueh, Yi-Yun; Wu, Ying-Chang; Chin, Chuan; Lin, Kuei-Hsiang

    2003-07-01

    Taiwan has experienced several major outbreaks of dengue (DEN) virus since 1981. The predominant virus type involved has been dengue virus type one (DEN-1), which first appeared in 1987. To understand the molecular epidemiology of this virus, 15 strains of DEN-1 isolated during 1987-1991 and 1994-1995, including 11 epidemic strains, two sporadic strains, and two imported strains have been studied. Fragments of 490 nucleotides (nt) from the E/NS1 junction were amplified by reverse transcription-polymerase chain reaction and the nt sequences were determined. Of the 490 nt of the E/NS1 junction, 240 nt (nt 2282-2521) were aligned and compared. Nucleotide substitutions were found at 54 positions among 15 isolates. Most nt changes were synonymous substitutions, and only three amino acid changes were found. A total of 61 strains isolated worldwide were analyzed by the Neighbor-joining method, and separated phylogenetically into three distinct genotypes, I-III. Genotype I comprised isolates from Japan and Hawaii collected in the 1940s. Genotype II included most strains isolated from Asia in 1977-1995. Genotype III consisted of isolates from three continents in 1964-1995: Asia, the Americas, and Africa. Genotype III was divided further into two subgenotypes, IIIA and IIIB. Most recent isolates from Taiwan, except for the sporadic strain isolated in 1995, were similar genetically and have been classified as Genotype II. PMID:12767004

  3. Epidemiologic studies of ionizing radiation and cancer: past successes and future challenges.

    PubMed Central

    Samet, J M

    1997-01-01

    The health effects of radiation have been a focus for research since early in the 20th century. As the century ends, extensive experimental and epidemiologic evidence has been accumulated that addresses the adverse consequences of radiation exposure; epidemiologic studies of radiation-exposed groups from the general population and specific occupational groups provide quantitative estimates of the cancer risks associated with exposure. This report provides a perspective on the extensive epidemiologic evidence on the health effects of ionizing radiation and on likely needs for further epidemiologic research on radiation and health. Epidemiologic studies have proved informative on the quantitative risks of radiation-caused cancer but we now face the challenges of more precisely characterizing risks at lower levels of exposure and also of assessing modifiers of the risks, including dose rate, genetic susceptibility, and other environmental exposures. This report considers investigative approaches, such as pooled analysis of multiple data sets, that can be used to address these complex questions and the limitations of these approaches for addressing societal concerns about the risks of radiation exposure. PMID:9255575

  4. 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

  5. Chapter 2. Fasciola, lymnaeids and human fascioliasis, with a global overview on disease transmission, epidemiology, evolutionary genetics, molecular epidemiology and control.

    PubMed

    Mas-Coma, Santiago; Valero, María Adela; Bargues, María Dolores

    2009-01-01

    Fascioliasis, caused by liver fluke species of the genus Fasciola, has always been well recognized because of its high veterinary impact but it has been among the most neglected diseases for decades with regard to human infection. However, the increasing importance of human fascioliasis worldwide has re-launched interest in fascioliasis. From the 1990s, many new concepts have been developed regarding human fascioliasis and these have furnished a new baseline for the human disease that is very different to a simple extrapolation from fascioliasis in livestock. Studies have shown that human fascioliasis presents marked heterogeneity, including different epidemiological situations and transmission patterns in different endemic areas. This heterogeneity, added to the present emergence/re-emergence of the disease both in humans and animals in many regions, confirms a worrying global scenario. The huge negative impact of fascioliasis on human communities demands rapid action. When analyzing how better to define control measures for endemic areas differing at such a level, it would be useful to have genetic markers that could distinguish each type of transmission pattern and epidemiological situation. Accordingly, this chapter covers aspects of aetiology, geographical distribution, epidemiology, transmission and control in order to obtain a solid baseline for the interpretation of future results. The origins and geographical spread of F. hepatica and F. gigantica in both the ruminant pre-domestication times and the livestock post-domestication period are analyzed. Paleontological, archaeological and historical records, as well as genetic data on recent dispersal of livestock species, are taken into account to establish an evolutionary framework for the two fasciolids across all continents. Emphasis is given to the distributional overlap of both species and the roles of transportation, transhumance and trade in the different overlap situations. Areas with only one Fasciola

  6. 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

  7. 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

  8. 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

  9. 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

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

    PubMed

    Mirajkar, Nandita S; Bekele, Aschalew Z; Chander, Yogesh Y; Gebhart, Connie J

    2015-09-01

    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

  11. 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…

  12. Anthrax in the Gambia: an epidemiological study

    PubMed Central

    Heyworth, B; Ropp, M E; Voos, U G; Meinel, H I; Darlow, H M

    1975-01-01

    Epidemiological data on 448 cases of human cutaneous anthrax from the Gambia showed that this particular strain of anthrax bacillus causes widespread morbidity and some mortality with, at the same time, subclinical infection. Analysis also showed that anthrax is not an occupationally related disease in the Gambia. The possibility of human-to-human spread, affecting all age groups and both sexes, by means of a communal toilet article was also shown. The fact that the strain is a good toxin producer but contains a weak antigen may have accounted for the repeated clinical infection and the fact that antibody titres were generally transient. Subclinical infection in animals was also found, particularly in sheep and goats, and also, with an unusually low mortality, in cows. Insect vectors were not excluded, but were unlikely. Vultures may spread the disease from village to village. Some possible public health and immunization procedures are discussed, with a view to containing this difficult problem in this part of west Africa. PMID:810213

  13. The Role of DNA Methylation in Cardiovascular Risk and Disease: Methodological Aspects, Study Design, and Data Analysis for Epidemiological Studies.

    PubMed

    Zhong, Jia; Agha, Golareh; Baccarelli, Andrea A

    2016-01-01

    Epidemiological studies have demonstrated that genetic, environmental, behavioral, and clinical factors contribute to cardiovascular disease development. How these risk factors interact at the cellular level to cause cardiovascular disease is not well known. Epigenetic epidemiology enables researchers to explore critical links between genomic coding, modifiable exposures, and manifestation of disease phenotype. One epigenetic link, DNA methylation, is potentially an important mechanism underlying these associations. In the past decade, there has been a significant increase in the number of epidemiological studies investigating cardiovascular risk factors and outcomes in relation to DNA methylation, but many gaps remain in our understanding of the underlying cause and biological implications. In this review, we provide a brief overview of the biology and mechanisms of DNA methylation and its role in cardiovascular disease. In addition, we summarize the current evidence base in epigenetic epidemiology studies relevant to cardiovascular health and disease and discuss the limitations, challenges, and future directions of the field. Finally, we provide guidelines for well-designed epigenetic epidemiology studies, with particular focus on methodological aspects, study design, and analytical challenges. PMID:26837743

  14. A Review for Detecting Gene-Gene Interactions Using Machine Learning Methods in Genetic Epidemiology

    PubMed Central

    Koo, Ching Lee; Liew, Mei Jing; Mohamad, Mohd Saberi

    2013-01-01

    Recently, the greatest statistical computational challenge in genetic epidemiology is to identify and characterize the genes that interact with other genes and environment factors that bring the effect on complex multifactorial disease. These gene-gene interactions are also denoted as epitasis in which this phenomenon cannot be solved by traditional statistical method due to the high dimensionality of the data and the occurrence of multiple polymorphism. Hence, there are several machine learning methods to solve such problems by identifying such susceptibility gene which are neural networks (NNs), support vector machine (SVM), and random forests (RFs) in such common and multifactorial disease. This paper gives an overview on machine learning methods, describing the methodology of each machine learning methods and its application in detecting gene-gene and gene-environment interactions. Lastly, this paper discussed each machine learning method and presents the strengths and weaknesses of each machine learning method in detecting gene-gene interactions in complex human disease. PMID:24228248

  15. A review for detecting gene-gene interactions using machine learning methods in genetic epidemiology.

    PubMed

    Koo, Ching Lee; Liew, Mei Jing; Mohamad, Mohd Saberi; Salleh, Abdul Hakim Mohamed

    2013-01-01

    Recently, the greatest statistical computational challenge in genetic epidemiology is to identify and characterize the genes that interact with other genes and environment factors that bring the effect on complex multifactorial disease. These gene-gene interactions are also denoted as epitasis in which this phenomenon cannot be solved by traditional statistical method due to the high dimensionality of the data and the occurrence of multiple polymorphism. Hence, there are several machine learning methods to solve such problems by identifying such susceptibility gene which are neural networks (NNs), support vector machine (SVM), and random forests (RFs) in such common and multifactorial disease. This paper gives an overview on machine learning methods, describing the methodology of each machine learning methods and its application in detecting gene-gene and gene-environment interactions. Lastly, this paper discussed each machine learning method and presents the strengths and weaknesses of each machine learning method in detecting gene-gene interactions in complex human disease. PMID:24228248

  16. 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

  17. Epidemiological studies are like cherries, one draws another.

    PubMed

    Lunet, Nuno

    2009-01-01

    The proverb "Words are like cherries", meaning that when you start talking subjects pop up and you end up with long conversations, just like cherries coming out of the plate in chains when you pick one, may also be applied to epidemiological research. A sequence of epidemiological studies, each being drawn from the previous, is presented as an example of how each investigation may raise new questions to be addressed in following studies. This description stresses the need for appropriate planning and the usefulness of pilot testing to depict inadequacies that can hardly be anticipated without field work. I intend to illustrate how epidemiological research can provide a deep approach to research questions, as long as findings are properly interpreted and suboptimal methodological options are taken into account in future investigations. PMID:19713008

  18. 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

  19. 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

  20. CRITICAL REVIEW OF EPIDEMIOLOGIC STUDIES RELATED TO INGESTED ASBESTOS

    EPA Science Inventory

    Thirteen epidemiologic studies of ingested asbestos conducted in five areas of the U.S. and Canada were reviewed and evaluated for the definitiveness and applicability regarding the development of ambient water quality standards. One or more studies found male or female associati...

  1. CHLORINE DIOXIDE WATER DISINFECTION: A PROSPECTIVE EPIDEMIOLOGY STUDY

    EPA Science Inventory

    An epidemiologic study of 198 persons exposed for 3 months to drinking water disinfected with chlorine dioxide was conducted in a rural village. A control population of 118 nonexposed persons was also studied. Pre-exposure hematologic and serum chemical parameters were compared w...

  2. IMPROVING EXPOSURE ASSESSMENT IN DISINFECTION BYPRODUCTS (DBP) EPIDEMIOLOGIC STUDIES

    EPA Science Inventory

    In 1997, an EPA expert panel was convened to evaluate epidemiologic studies of adverse reproductive or developmental outcomes that may be associated with drinking water DBPs. The panel recommended that further efforts be made in an existing cohort study, headed by Dr. Waller and ...

  3. 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…

  4. 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

  5. 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

  6. 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

  7. Adverse reproductive outcomes in families of atomic veterans: The feasibility of epidemiologic studies

    SciTech Connect

    1995-12-31

    This is an outstanding report from a distinguished academy committee, which in 71 pages of text provides the scientific basis for the carefully crafted 8-page executive summary. The principles and issues of the required epidemiological study are presented calmly and concisely, as are the ensuing short chapters on radiation biology, genetics and risk estimation, and all other adverse reproductive outcomes. The committee was mandated by Congress to determine the feasibility, cost and duration of a study on adverse reproductive outcomes in families of atomic veteran. The committee found that a scientifically adequate and epidemiologically valid study could not be mounted and the cost would be tens of millions of dollars lasting a decade. The Committee presents a number of well-discussed approaches in support of their position.

  8. Standards for epidemiologic studies and surveillance of epilepsy.

    PubMed

    Thurman, David J; Beghi, Ettore; Begley, Charles E; Berg, Anne T; Buchhalter, Jeffrey R; Ding, Ding; Hesdorffer, Dale C; Hauser, W Allen; Kazis, Lewis; Kobau, Rosemarie; Kroner, Barbara; Labiner, David; Liow, Kore; Logroscino, Giancarlo; Medina, Marco T; Newton, Charles R; Parko, Karen; Paschal, Angelia; Preux, Pierre-Marie; Sander, Josemir W; Selassie, Anbesaw; Theodore, William; Tomson, Torbjörn; Wiebe, Samuel

    2011-09-01

    Worldwide, about 65 million people are estimated to have epilepsy. Epidemiologic studies are necessary to define the full public health burden of epilepsy; to set public health and health care priorities; to provide information needed for prevention, early detection, and treatment; to identify education and service needs; and to promote effective health care and support programs for people with epilepsy. However, different definitions and epidemiologic methods complicate the tasks of these studies and their interpretations and comparisons. The purpose of this document is to promote consistency in definitions and methods in an effort to enhance future population-based epidemiologic studies, facilitate comparison between populations, and encourage the collection of data useful for the promotion of public health. We discuss: (1) conceptual and operational definitions of epilepsy, (2) data resources and recommended data elements, and (3) methods and analyses appropriate for epidemiologic studies or the surveillance of epilepsy. Variations in these are considered, taking into account differing resource availability and needs among countries and differing purposes among studies. PMID:21899536

  9. 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

  10. 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 studies. 159.170 Section 159.170 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... that a correlation may exist between exposure to a pesticide and observed adverse effects in...

  11. 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 studies. 159.170 Section 159.170 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... that a correlation may exist between exposure to a pesticide and observed adverse effects in...

  12. 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. PMID:26194649

  13. 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

  14. Assessment of environmental and genetic factors in the etiology of childhood cancers: the Childrens Cancer Group epidemiology program.

    PubMed Central

    Robison, L L; Buckley, J D; Bunin, G

    1995-01-01

    The occurrence of cancer during childhood represents one of the leading causes of death within the pediatric and adolescent age group. It is estimated that approximately 8000 children will be diagnosed annually with cancer in the United States. Epidemiologic research addressing the etiology of childhood cancer has been limited because of the difficulties in identifying a sufficiently large study population. Moreover, the use of retrospectively ascertained childhood cancer cases in epidemiologic investigations has restricted the incorporation of biological and clinical parameters. The Childrens Cancer Group has developed an active program in epidemiologic research, with over a decade of experience demonstrating the feasibility and strengths of conducting analytic epidemiologic studies within a cooperative clinical trials network. The availability of detailed clinical and biologic data on cases diagnosed within the cooperative group facilitates the transfer of state-of-the-art technology to epidemiologic research. PMID:8549456

  15. 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

  16. [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

  17. 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

  18. 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

  19. 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

  20. 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

  1. Myasthenia gravis on the Dutch antilles: an epidemiological study.

    PubMed

    Holtsema, H; Mourik, J; Rico, R E; Falconi, J R; Kuks, J B; Oosterhuis, H J

    2000-12-01

    We carried out an epidemiological study on the prevalence and annual incidence of myasthenia gravis on tropical islands Curaçao and Aruba in the period 1980-1995. Twenty-one patients (seven men and 14 women) were identified. The point prevalence increased from 29 per million in 1980 to about 70 per million in 1990-1995; the annual incidence over the total period was 4.7 per million. The female:male ratio was 2:1; purely ocular cases (2/21) comprised 9.5% and thymomas (4/21), 19%. These data are in accordance with most other epidemiological studies in non-tropical areas. No other studies on myasthenia gravis in tropical areas have been reported. PMID:11154803

  2. 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.

  3. [RET/PTC Gene Rearrangements in the Sporadic and Radiogenic Thyroid Tumors: Molecular Genetics, Radiobiology and Molecular Epidemiology].

    PubMed

    Ushenkova, L N; Koterov, A N; Biryukov, A P

    2015-01-01

    A review of molecular genetic, radiobiological and molecular epidemiological studies of gene (chromosome) rearrangements RET/PTC in the cells of the thyroid gland as well as the laws in relation to radiation exposure in vitro, in vivo and human populations identified with them are submitted. The data on the c-RET gene and its chimeric constructs with the gene-donors (RET/PTC rearrangements) are considered. The information about the history of the RET/PTC discovery, their types, carcinogenic potential and specificity both to tumor and non-tumor thyroid disease especially for papillary thyroid carcinoma are provided. The data (seven studies) on the induction of RET/PTC after irradiation of tumor and normal thyroid cells in vitro and mice are reviewed. The mechanisms of RET/PTC induction may be associated with DNA double strand breaks and oxidative stress. Some information (three publications) about the possibility of RET/PTC induction by low doses of radiation with low LET (to 0.1 Gy) is given and it is concluded that their potential evidentiary is generally weak. The achievements in the molecular epidemiology of RET/PTC frequency for exposed and unexposed cohorts are stated. At the same time it is noted that, despite the vast array. of data accumulated from 30 countries of the world and more than 20 years of research, the formed provisions are weakly confirmed statistically and have no base corresponding to the canons of evidence-based medicine. The possibility of use of the RET/PTC presence or their frequencies as markers of the papillary thyroid carcinomas and, specifically, their radiogenic forms, is considered. In the first case the answer may be positive, while in the second, the situation is characterized by uncertainty. Based to the above mentioned we came to a conclusion about the need of a pooled or meta-analysis of the totality of the published data. PMID:26310016

  4. Epidemiologic studies of Cyclospora cayetanensis in Guatemala.

    PubMed

    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

  5. 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

  6. 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

  7. 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

  8. Trachoma in the Sudan. An epidemiological study.

    PubMed Central

    Salim, A R; Sheikh, H A

    1975-01-01

    The prevalence and distribution of trachoma in the Sudan has been studied. The morbidity rate of 83.2 per 1000 in the Northern Province decreases southwards until it reaches 0.94 in the extreme south (Equatoria Province). 2. In endemic areas infection starts very early--in the first year of life. 3. There is a marked difference between the prevalence of trachoma in towns and villages--71.3 per cent for the age group 1-4 years in villages, and 56.7 per cent for the same age group in the towns. This is probably due to better standards of living and hygiene in the towns. 4. Some relationship has been found between the rainfall, the relative humidity, and the incidence of trachoma, but this does not necessarily apply in other countries. 5. The factors that may explain the high prevalence of trachoma in the northern Sudan are: a. Mechanical trauma caused by frequent sandstorms. b. Irritation of the eyes by dust particles, leading to excessive watering and discharge, and rubbing with the fingers. c. The habit of frequent hand-shaking. d. Poor personal hygiene in pre-schoolchildren. e. Associated bacterial conjunctivitis. f. The presence of eye-seeking flies. PMID:1191619

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

    SciTech Connect

    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.

  10. 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

  11. 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

  12. Size distribution of airborne particles controls outcome of epidemiological studies.

    PubMed

    Harrison, Roy M; Giorio, Chiara; Beddows, David C S; Dall'Osto, Manuel

    2010-12-15

    Epidemiological studies typically using wide size range mass metrics (e.g. PM(10)) have demonstrated associations between airborne particulate matter and several adverse health outcomes. This approach ignores the fact that mass concentration may not correlate with regional lung dose, unlike the case of trace gases. When using measured particle size distributions as the basis for calculating regional lung dose, PM(10) mass concentration is found to be a good predictor of the mass dose in all regions of the lung, but is far less predictive of the surface area and particle number dose. On the other hand, measurements of particle number do not well predict mass dose, indicating that the chosen particle metric is likely to determine the health outcomes detectable by an epidemiological study. Consequently, epidemiological studies using mass metrics (PM(2.5) and PM(10)) may fail to recognise important health consequences of particulate matter exposure, leading to an underestimate of the public health consequences of particle exposure. PMID:21109288

  13. [Genetic study of allergic diseases].

    PubMed

    Zhang, Yuan; Zhang, Luo

    2012-09-01

    Allergic diseases mentioned in this review is regarding to I type allergic inflammation induced by an IgE-mediated reaction, including asthma, allergic rhinitis, atopic dermatitis and food allergy. It is convinced that allergic diseases belong to multiple genes diseases and are controlled by both genetic and environmental factors. Meanwhile there exists gene-gene as well as gene-environment interactions during the development of the disease. The aim of this review is to summarize the toolkit, advance, inherent difficulties and future clinical application prospect in genetic studies of allergic disease. PMID:23214325

  14. 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

  15. 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

  16. 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...

  17. 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...

  18. 10 CFR 602.5 - Epidemiology and Other Health Studies Financial Assistance Program.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 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...

  19. 10 CFR 602.5 - Epidemiology and Other Health Studies Financial Assistance Program.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 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...

  20. 10 CFR 602.5 - Epidemiology and Other Health Studies Financial Assistance Program.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 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...

  1. 10 CFR 602.5 - Epidemiology and Other Health Studies Financial Assistance Program.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 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...

  2. Environmental epidemiology of intestinal schistosomiasis and genetic diversity of Schistosoma mansoni infections in snails at Bugoigo village, Lake Albert.

    PubMed

    Levitz, Sarah; Standley, Claire J; Adriko, Moses; Kabatereine, Narcis B; Stothard, J Russell

    2013-11-01

    Intestinal schistosomiasis continues to be hyper-endemic in the fishing community of Bugoigo located on the eastern shore of Lake Albert, Uganda. Our study aimed to identify the factors that determine the local distribution and abundance of Biomphalaria, as well as infection(s) with Schistosoma mansoni inclusive of their genetic diversity. In addition, a DNA barcoding approach was taken to genotype schistosome cercariae, exploring the micro-epidemiology of infections. Over a 3-week period in June-July 2010, several hundred Biomphalaria spp. were collected, together with environmental information, from 10 selected sites, representative of both putative wave-exposed (n=5) and wave-sheltered shorelines (n=5). A Mann-Whitney U-test and a generalized linear model were used to assess associations with snail abundance and parasite infections across the shoreline. Levels of local wave action were recorded over the 19-day period using digital accelerometers. The general absence of wave action on the sheltered shoreline likely helped to raise and focalize other environmental parameters, such as water conductivity by lack of mixing, that foster transmission of intestinal schistosomiasis. Over the study period, a total of 10 infected snails were encountered and a selection of schistosome cercariae from each infected snail was harvested for analysis by DNA barcoding. In total, 91 DNA barcodes were generated with 15 unique barcode types identified. Of these, 4 barcodes had been found previously in Lake Albert and (or) Victoria, the remaining 11 were newly encountered here and described. The distribution of DNA barcodes across infected snails and sampled locations revealed a complicated spatial sub-structuring. By shedding new light on the fine-scale patterning of infections, DNA barcoding has revealed a rather heterogeneous landscape of cercariae, likely inclusive of multi-miracidial infections within the snail, which will in turn interplay with human water contact activities to

  3. 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

  4. Carcinoma of the stomach: A review of epidemiology, pathogenesis, molecular genetics and chemoprevention

    PubMed Central

    Nagini, Siddavaram

    2012-01-01

    Carcinoma of the stomach is still the second most common cause of cancer death worldwide, although the incidence and mortality have fallen dramatically over the last 50 years in many regions. The incidence of gastric cancer varies in different parts of the world and among various ethnic groups. Despite advances in diagnosis and treatment, the 5-year survival rate of stomach cancer is only 20 per cent. Stomach cancer can be classified into intestinal and diffuse types based on epidemiological and clinicopathological features. The etiology of gastric cancer is multifactorial and includes both dietary and nondietary factors. The major diet-related risk factors implicated in stomach cancer development include high content of nitrates and high salt intake. Accumulating evidence has implicated the role of Helicobacter pylori (H. pylori) infection in the pathogenesis of gastric cancer. The development of gastric cancer is a complex, multistep process involving multiple genetic and epigenetic alterations of oncogenes, tumor suppressor genes, DNA repair genes, cell cycle regulators, and signaling molecules. A plausible program for gastric cancer prevention involves intake of a balanced diet containing fruits and vegetables, improved sanitation and hygiene, screening and treatment of H. pylori infection, and follow-up of precancerous lesions. The fact that diet plays an important role in the etiology of gastric cancer offers scope for nutritional chemoprevention. Animal models have been extensively used to analyze the stepwise evolution of gastric carcinogenesis and to test dietary chemopreventive agents. Development of multitargeted preventive and therapeutic strategies for gastric cancer is a major challenge for the future. PMID:22844547

  5. Carcinoma of the stomach: A review of epidemiology, pathogenesis, molecular genetics and chemoprevention.

    PubMed

    Nagini, Siddavaram

    2012-07-15

    Carcinoma of the stomach is still the second most common cause of cancer death worldwide, although the incidence and mortality have fallen dramatically over the last 50 years in many regions. The incidence of gastric cancer varies in different parts of the world and among various ethnic groups. Despite advances in diagnosis and treatment, the 5-year survival rate of stomach cancer is only 20 per cent. Stomach cancer can be classified into intestinal and diffuse types based on epidemiological and clinicopathological features. The etiology of gastric cancer is multifactorial and includes both dietary and nondietary factors. The major diet-related risk factors implicated in stomach cancer development include high content of nitrates and high salt intake. Accumulating evidence has implicated the role of Helicobacter pylori (H. pylori) infection in the pathogenesis of gastric cancer. The development of gastric cancer is a complex, multistep process involving multiple genetic and epigenetic alterations of oncogenes, tumor suppressor genes, DNA repair genes, cell cycle regulators, and signaling molecules. A plausible program for gastric cancer prevention involves intake of a balanced diet containing fruits and vegetables, improved sanitation and hygiene, screening and treatment of H. pylori infection, and follow-up of precancerous lesions. The fact that diet plays an important role in the etiology of gastric cancer offers scope for nutritional chemoprevention. Animal models have been extensively used to analyze the stepwise evolution of gastric carcinogenesis and to test dietary chemopreventive agents. Development of multitargeted preventive and therapeutic strategies for gastric cancer is a major challenge for the future. PMID:22844547

  6. 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

  7. Crimean-Congo hemorrhagic fever: history, epidemiology, pathogenesis, clinical syndrome and genetic diversity.

    PubMed

    Bente, Dennis A; Forrester, Naomi L; Watts, Douglas M; McAuley, Alexander J; Whitehouse, Chris A; Bray, Mike

    2013-10-01

    Crimean-Congo hemorrhagic fever (CCHF) is the most important tick-borne viral disease of humans, causing sporadic cases or outbreaks of severe illness across a huge geographic area, from western China to the Middle East and southeastern Europe and throughout most of Africa. CCHFV is maintained in vertical and horizontal transmission cycles involving ixodid ticks and a variety of wild and domestic vertebrates, which do not show signs of illness. The virus circulates in a number of tick genera, but Hyalomma ticks are the principal source of human infection, probably because both immature and adult forms actively seek hosts for the blood meals required at each stage of maturation. CCHF occurs most frequently among agricultural workers following the bite of an infected tick, and to a lesser extent among slaughterhouse workers exposed to the blood and tissues of infected livestock and medical personnel through contact with the body fluids of infected patients. CCHFV is the most genetically diverse of the arboviruses, with nucleotide sequence differences among isolates ranging from 20% for the viral S segment to 31% for the M segment. Viruses with diverse sequences can be found within the same geographic area, while closely related viruses have been isolated in far distant regions, suggesting that widespread dispersion of CCHFV has occurred at times in the past, possibly by ticks carried on migratory birds or through the international livestock trade. Reassortment among genome segments during co-infection of ticks or vertebrates appears to have played an important role in generating diversity, and represents a potential future source of novel viruses. In this article, we first review current knowledge of CCHFV, summarizing its molecular biology, maintenance and transmission, epidemiology and geographic range. We also include an extensive discussion of CCHFV genetic diversity, including maps of the range of the virus with superimposed phylogenetic trees. We then review

  8. Multilocus microsatellite genotyping array for investigation of genetic epidemiology of Pneumocystis jirovecii.

    PubMed

    Parobek, Christian M; Jiang, Linda Y; Patel, Jaymin C; Alvarez-Martínez, Miriam J; Miro, Jose M; Worodria, William; Andama, Alfred; Fong, Serena; Huang, Laurence; Meshnick, Steven R; Taylor, Steve M; Juliano, Jonathan J

    2014-05-01

    Pneumocystis jirovecii is a symbiotic respiratory fungus that causes pneumonia (PcP) in immunosuppressed patients. Because P. jirovecii cannot be reliably cultured in vitro, it has proven difficult to study and gaps in our understanding of the organism persist. The release of a draft genome for the organism opens the door for the development of new genotyping approaches for studying its molecular epidemiology and global population structure. We identified and validated 8 putatively neutral microsatellite markers and 1 microsatellite marker linked to the dihydropteroate synthase gene (dhps), the enzymatic target of sulfa drugs used for PcP prevention and treatment. Using these tools, we analyzed P. jirovecii isolates from HIV-infected patients from three geographically distant populations: Uganda, the United States, and Spain. Among the 8 neutral markers, we observed high levels of allelic heterozygosity (average He, 0.586 to 0.842). Consistent with past reports, we observed limited global population structuring, with only the Ugandan isolates showing minor differentiation from the other two populations. In Ugandan isolates that harbored mutations in dhps, the microsatellite locus linked to dhps demonstrated a depressed He, consistent with positive directional selection for sulfa resistance mutations. Using a subset of these microsatellites, analyses of individual and paired samples from infections in San Francisco, CA, showed reliable typeability within a single infection and high discriminatory power between infections. These features suggest that this novel microsatellite typing approach will be an effective tool for molecular-epidemiological investigations into P. jirovecii population structure, transmission, and drug resistance. PMID:24523468

  9. 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

  10. Epidemiological studies in incidence, prevalence, mortality, and comorbidity of the rheumatic diseases

    PubMed Central

    Gabriel, Sherine E; Michaud, Kaleb

    2009-01-01

    Epidemiology is the study of the distribution and determinants of disease in human populations. Over the past decade there has been considerable progress in our understanding of the fundamental descriptive epidemiology (levels of disease frequency: incidence and prevalence, comorbidity, mortality, trends over time, geographic distributions, and clinical characteristics) of the rheumatic diseases. This progress is reviewed for the following major rheumatic diseases: rheumatoid arthritis (RA), juvenile rheumatoid arthritis, psoriatic arthritis, osteoarthritis, systemic lupus erythematosus, giant cell arteritis, polymyalgia rheumatica, gout, Sjögren's syndrome, and ankylosing spondylitis. These findings demonstrate the dynamic nature of the incidence and prevalence of these conditions – a reflection of the impact of genetic and environmental factors. The past decade has also brought new insights regarding the comorbidity associated with rheumatic diseases. Strong evidence now shows that persons with RA are at a high risk for developing several comorbid disorders, that these conditions may have atypical features and thus may be difficult to diagnose, and that persons with RA experience poorer outcomes after comorbidity compared with the general population. Taken together, these findings underscore the complexity of the rheumatic diseases and highlight the key role of epidemiological research in understanding these intriguing conditions. PMID:19519924

  11. Contributions of occupational epidemiologic studies to radiation protection

    SciTech Connect

    Marks, S.

    1982-01-01

    Early evidence of health effects of occupational radiation exposure contributed importantly to the establishment of exposure standards, especially for internal emitters. Standards derived in this manner for radium body burdens and for air concentrations of radon and its daughters were especially influential. The body burden limits for plutonium and other bone-seeking radionuclides were based upon the radium standard. The exposure controls instituted as a consequence of those early limits have reduced the exposure of worker populations to the extent that the current, more sophisticated epidemiologic studies will probably not influence the revision of existing standards. The justification for conducting such studies is discussed.

  12. 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

  13. TCDD and cancer: A critical review of epidemiologic studies

    PubMed Central

    Boffetta, Paolo; Mundt, Kenneth A; Adami, Hans-Olov; Cole, Philip; Mandel, Jack S

    2011-01-01

    The authors reviewed the epidemiologic studies on exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and cancer risk, published since the last full-scale review made by the International Agency for Research on Cancer Monographs program in 1997. The update of a cohort of US herbicide producers generated negative results overall; the internal analysis provided evidence of an increased “all-cancer” risk in the highest exposure category, with a statistically significant exposure-response association in some of the many analyses performed.The update of a similar Dutch cohort did not confirm the previously observed association with TCDD exposure. The updated surveillance of the Seveso population provided evidence of increased all-cancer mortality 15-20 years after exposure among those living in the most contaminated area but might also reflect random variation, as overall excesses in the most recent follow-up were not observed. Corresponding data on cancer incidence offer little support to the mortality results. Updated results from cohort studies of Vietnam veterans potentially exposed to TCDD did not consistently suggest an increased risk of cancer. Results of additional, smaller studies of other occupational groups potentially exposed to TCDD, and of community-based case-control studies, did not provide consistent evidence of an increased cancer risk. In conclusion, recent epidemiological evidence falls far short of conclusively demonstrating a causal link between TCDD exposure and cancer risk in humans. The emphasis on results for overall cancer risk—rather than risk for specific neoplasms—is notjustified on epidemiologic grounds and is nota reason for ignoring the weaknesses of the available evidence. PMID:21718216

  14. Mining characteristics of epidemiological studies from Medline: a case study in obesity

    PubMed Central

    2014-01-01

    Background The health sciences literature incorporates a relatively large subset of epidemiological studies that focus on population-level findings, including various determinants, outcomes and correlations. Extracting structured information about those characteristics would be useful for more complete understanding of diseases and for meta-analyses and systematic reviews. Results We present an information extraction approach that enables users to identify key characteristics of epidemiological studies from MEDLINE abstracts. It extracts six types of epidemiological characteristic: design of the study, population that has been studied, exposure, outcome, covariates and effect size. We have developed a generic rule-based approach that has been designed according to semantic patterns observed in text, and tested it in the domain of obesity. Identified exposure, outcome and covariate concepts are clustered into health-related groups of interest. On a manually annotated test corpus of 60 epidemiological abstracts, the system achieved precision, recall and F-score between 79-100%, 80-100% and 82-96% respectively. We report the results of applying the method to a large scale epidemiological corpus related to obesity. Conclusions The experiments suggest that the proposed approach could identify key epidemiological characteristics associated with a complex clinical problem from related abstracts. When integrated over the literature, the extracted data can be used to provide a more complete picture of epidemiological efforts, and thus support understanding via meta-analysis and systematic reviews. PMID:24949194

  15. Critical review of epidemiologic studies related to ingested asbestos

    SciTech Connect

    Marsh, G.M.

    1983-11-01

    Thirteen epidemiologic studies of ingested asbestos conducted in five areas of the US and Canada were evaluated for the definitiveness and applicability regarding the development of ambient water quality standards. Associations between asbestos in water supplies and cancer mortality or incidence in humans were found in one or more studies dealing with neoplasms in the esophagus, stomach, small intestine, colon, rectum, gallbaldder, pancreas, peritoneum, lungs, pleura, prostate, kidneys, brain and thyroid as well as leukemia. However, no single study nor aggregate of studies existed that would establish risk levels from ingested asbestos. It is recommended that the integrated ecologic data to date be used to generate a rough priority of specific etiologic hypotheses that should be tested in the original settings or in independent study populations using studies designed at the more definitive individual level, such as case-control studies. 25 references, 7 tables.

  16. The epidemiology of vertebral fractures. European Vertebral Osteoporosis Study Group.

    PubMed

    Cooper, C; O'Neill, T; Silman, A

    1993-01-01

    Vertebral fractures are recognised as a hallmark of osteoporosis, yet little is known of their epidemiology. This deficiency limits accurate characterisation of the public health importance of osteoporosis. Assessment of the impact of vertebral fractures has been hampered by the absence of formal criteria for identifying fractures on a thoracolumbar radiograph. Initial methods relying upon subjective radiological assessments have given way to morphometric measurements of vertebral heights, with deformities defined according to various algorithms. These methods have been used in a series of studies performed in Rochester, MN, to determine the incidence, outcome, and time trends of vertebral deformities. The results suggest a prevalence rate of vertebral deformity of 25.3 per 100 Rochester women aged 50 years and over (95% CI, 22.3-28.2), with an estimated incidence of 17.8 per 1,000 person-years. The incidence of clinically diagnosed vertebral fractures among women in the same population was 5.3 per 1,000 person-years, suggesting that around 30% of such deformities in women receive clinical attention. Morphometric measurement on the radiographs of women with clinically diagnosed fractures revealed that 80% had grade 2 ( > 4 SD) deformities. Comparable data on the occurrence and health impact of vertebral deformities throughout Europe are urgently required. The European Vertebral Osteoporosis Study (EVOS) is a multicentre epidemiological study that aims to address this issue. It is designed as a radiographic prevalence study in 34 European centres.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8110529

  17. Drug data coding and analysis in epidemiologic studies.

    PubMed

    Pahor, M; Chrischilles, E A; Guralnik, J M; Brown, S L; Wallace, R B; Carbonin, P

    1994-08-01

    In epidemiologic studies that collect comprehensive information on medication use, the complexity of dealing with a large number of trade and generic names may limit the utilization of these data bases. This paper shows the specific advantage of using two coding systems, one to maximize efficiency of data entry, and the other to facilitate analysis by organizing the drug ingredients into hierarchical categories. The approach used by two large surveys, one in the USA and one in Italy, is described: the Established Populations for Epidemiologic Studies of the Elderly (EPESE) and the 'Gruppo Italiano di Farmacovigilanza nell' Anziano' (GIFA). To enter the medications into a computerized database, codes matching the drug product names are needed. In the EPESE the prescription and over the counter drug products are coded with the Drug Products Information Coding System (DPICS) and the Iowa Nonprescription Drug Products Information Coding System (INDPICS), respectively. The GIFA study uses the coding system of the Italian Ministry of Health (MINSAN), with a unique numeric code for each drug product available in Italy. To simplify the analytical process the drug entry codes are converted into hierarchical coding systems with unique codes for specific drug ingredients, chemical and therapeutic categories. The EPESE and GIFA drug data are coded with the Iowa Drug Information System (IDIS) ingredient codes, and the Anatomical Therapeutic and chemical (ATC) codes, respectively. Examples are provided that show coding of diuretics in these two studies and demonstrate the analytic advantages of these systems. PMID:7843344

  18. 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

  19. 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

  20. 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.

  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. 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).

  4. Epidemiologic study of ankle fractures in a tertiary hospital

    PubMed Central

    Sakaki, Marcos Hideyo; Matsumura, Bruno Akio Rodrigues; Dotta, Thiago De Angelis Guerra; Pontin, Pedro Augusto; dos Santos, Alexandre Leme Godoy; Fernandes, Tulio Diniz

    2014-01-01

    OBJECTIVES: To evaluate the epidemiology of ankle fractures surgically treated at the Instituto de Ortopedia e Traumatologia do Hospital das Clínicas da Universidade de São Paulo. METHODS: Medical records of patients admitted with foot and ankle fractures between 2006 and 2011 were revised. Seventy three ankle fractures that underwent surgical treatment were identified. The parameters analyzed included age, gender, injured side, AO and Gustilo & Anderson classification, associated injuries, exposure, need to urgent treatment, time to definitive treatment and early post-operative complications. Study design: retrospective epidemiological study. RESULTS: Male gender was predominant among subjects and the mean age was 27.5 years old. Thirty nine fractures resulted from traffic accidents and type B fracture according to AO classification was the most common. Twenty one were open fractures and 22 patients had associated injuries. The average time to definitive treatment was 6.5 days. Early post-operative complications were found in 21.3% of patients. CONCLUSIONS: Ankle fractures treated in a tertiary hospital of a large city in Brazil affect young people victims of high-energy accidents and present significant rates of associated injuries and post-operative complications. Level of Evidence IV, Cases Series. PMID:24868187

  5. Biologically based epidemiological studies of electric power and cancer.

    PubMed Central

    Stevens, R G

    1993-01-01

    As societies industrialize, the health profile of the population changes; in general, acute infectious disease declines and chronic disease increases. 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.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8206047

  6. [Epidemiology of myopia].

    PubMed

    Pechmann, A; Czepita, D

    2000-01-01

    The present state of knowledge on the epidemiology of myopia is discussed. The history of myopia investigations is described. The prevalence of myopia in different ages, races and populations is presented. The factors influencing myopia occurrence are characterized. Special attention is focused on the results of studies indicating environmental and genetic reasons of myopia. Most recent investigations concerning the influence of light on myopia occurrence as well as concerning a genetic locus for high myopia are described. PMID:11291303

  7. 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

  8. Optimal design for epidemiological studies subject to designed missingness.

    PubMed

    Morara, Michele; Ryan, Louise; Houseman, Andres; Strauss, Warren

    2007-12-01

    In large epidemiological studies, budgetary or logistical constraints will typically preclude study investigators from measuring all exposures, covariates and outcomes of interest on all study subjects. We develop a flexible theoretical framework that incorporates a number of familiar designs such as case control and cohort studies, as well as multistage sampling designs. Our framework also allows for designed missingness and includes the option for outcome dependent designs. Our formulation is based on maximum likelihood and generalizes well known results for inference with missing data to the multistage setting. A variety of techniques are applied to streamline the computation of the Hessian matrix for these designs, facilitating the development of an efficient software tool to implement a wide variety of designs. PMID:18080755

  9. 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…

  10. Using Computers to Survey the Epidemiological, Environmental and Genetic Factors Involved in the Process of Bacteria Resistance Acquisition

    PubMed Central

    Baccala, Luiz Antonio; Nicolelis, Miguel A.L.

    1989-01-01

    The sensitivity behavior in time of several species (S.aureus, E.coli, K.pneumoniae and P.mirabilis in a total of 16334 positive cultures collected at our hospital from July 1981 to December 1986) to amikacin and gentamicin are shown to be periodic. The implications of this finding, and parameters, both epidemiological and genetic, that might be of relevance in its understanding, are discussed as being necessary characteristics of a nosocomial survey-and-control computer system in which time-series analysis techniques are of central importance.

  11. 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.

  12. [French Guiana "papillonite" (lepidopterism). Clinical and epidemiological study].

    PubMed

    Ducombs, G; Lamy, M; Michel, M; Pradinaud, R; Jamet, P; Vincendeau, P; Maleville, J; Texier, L

    1983-01-01

    Clinical studies by Dr R. Pradinaud (Cayenne) has given prominence to the symptoms of "papillonite": its primary and secondary cutaneous lesions, their localisation and evolution as well as its accompanying symptoms such as respiratory pathology. Epidemiologic survey shows a parallelism between the occurrence of papillonite and the presence of the moth Hylesia urticans. The urticant apparatus of this moth was studied with the scanning electron microscope. "Arrow" (fléchettes) were found and they more or less resemble the urticant apparatus of Thaumetopoea pityocampa Schiff caterpillar. The mechanism of action has been studied in the animal and in humans. Extracts prepared from the "arrows" have been rested in vivo guinea-pigs (bleu Evans, Liacopoulos et al.). The findings seem to incriminate an histamino-liberation. PMID:6666924

  13. Genetic analysis and epidemiology of Crimean Congo hemorrhagic fever viruses in Baluchistan province of Pakistan

    PubMed Central

    2013-01-01

    Background Pakistan is considered as an endemic country for Crimean-Congo Hemorrhagic fever with numerous outbreaks and sporadic cases reported during the past two decades. Majority of cases are reported from Baluchistan province with subsequent transmissions to non-endemic regions mainly through infected animals directly or via infested ticks. We hereby describe the molecular investigations of CCHF cases reported during 2008 in Quetta city of Baluchistan province. Methods Serum Samples from 44 patients, with clinical signs of hemorrhagic fever attending a tertiary care hospital in Quetta city, were collected and tested for CCHF virus antigen and genomic RNA, using capture IgM EIA kit and standard RT-PCR assay, respectively. The partial S-gene fragments were directly sequenced to get information related to the prevailing CCHFV genotypes and their molecular epidemiology in Pakistan. Results Out of the total forty four, sixteen (36%) samples were found positive for CCHF IgM. Similarly, viral RNA was detected in six (16%) samples. Phylogenetic analysis revealed that all study viruses belong to genotype Asia-1 with closest similarity (99-100%) to the previously reported strains from Pakistan, Afghanistan and Iran. Conclusion We conclude that CCHF virus remains endemic within Baluchistan and its neighboring regions of Afghanistan warranting a need of incessant surveillance activities. PMID:23641865

  14. 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

  15. 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

  16. 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.

  17. 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

  18. 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

  19. [Alcohol and wine and cardiovascular diseases in epidemiologic studies].

    PubMed

    Sinkiewicz, Władysław; Weglarz, Magdalena

    2009-01-01

    Moderate alcohol intake is associated with lower risk of cardiovascular diseases. A large number of epidemiologic studies have demonstrated a U- or J-shaped relation between alcohol consumption and total mortality, coronary heart disease and ischemic stroke. The lowest risk occurs in those who drink one or two drinks per day. Many studies have dealt with the question if specific alcoholic beverage (vodka, beer, wine, liquor) might offer a greater protection. Red wine containing polyphenols is believed to possess exceptional cardioprotective properties, especially if consumed with meals. However, alcohol beverages should not be recommended to patients as a substitute for the well-proven, cardiovascular risk reducing alternatives such as low fat diet, exercise and pharmacotherapy. PMID:19739580

  20. Quality control for exposure assessment in epidemiological studies.

    PubMed

    Bornkessel, C; Blettner, M; Breckenkamp, J; Berg-Beckhoff, G

    2010-08-01

    In the framework of an epidemiological study, dosemeters were used for the assessment of radio frequency electromagnetic field exposure. To check the correct dosemeter's performance in terms of consistency of recorded field values over the entire study period, a quality control strategy was developed. In this paper, the concept of quality control and its results is described. From the 20 dosemeters used, 19 were very stable and reproducible, with deviations of a maximum of +/-1 dB compared with their initial state. One device was found to be faulty and its measurement data had to be excluded from the analysis. As a result of continuous quality control procedures, the confidence in the measurements obtained during the field work was strengthened significantly. PMID:20308051

  1. 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

  2. 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

  3. 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

  4. 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

  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). PMID:11928582

  6. Population-specific frequencies for LRRK2 susceptibility variants in the Genetic Epidemiology Of Parkinson’s Disease (GEO-PD) consortium

    PubMed Central

    Heckman, Michael G.; Soto-Ortolaza, Alexandra I.; Aasly, Jan O.; Abahuni, Nadine; Annesi, Grazia; Bacon, Justin A.; Bardien, Soraya; Bozi, Maria; Brice, Alexis; Brighina, Laura; Carr, Jonathan; Chartier-Harlin, Marie-Christine; Dardiotis, Efthimios; Dickson, Dennis W.; Diehl, Nancy N.; Elbaz, Alexis; Ferrarese, Carlo; Fiske, Brian; Gibson, J. Mark; Gibson, Rachel; Hadjigeorgiou, Georgios M.; Hattori, Nobutaka; Hentati, Faycal; Ioannidis, John P.A.; Boczarska-Jedynak, Magdalena; Jasinska-Myga, Barbara; Jeon, Beom S.; Kim, Yun Joong; Klein, Christine; Kruger, Rejko; Kyratzi, Elli; Lesage, Suzanne; Lin, Chin-Hsien; Lynch, Timothy; Maraganore, Demetrius M.; Mellick, George D.; Mutez, Eugénie; Nilsson, Christer; Opala, Grzegorz; Park, Sung Sup; Petrucci, Simona; Puschmann, Andreas; Quattrone, Aldo; Sharma, Manu; Silburn, Peter A.; Sohn, Young Ho; Stefanis, Leonidas; Tadic, Vera; Theuns, Jessie; Tomiyama, Hiroyuki; Uitti, Ryan J.; Valente, Enza Maria; Van Broeckhoven, Christine; van de Loo, Simone; Vassilatis, Demetrios K.; Vilariño-Güell, Carles; White, Linda R.; Wirdefeldt, Karin; Wszolek, Zbigniew K.; Wu, Ruey-Meei; Farrer, Matthew J.; Ross, Owen A.

    2014-01-01

    Variants within the leucine-rich repeat kinase 2 gene are recognized as the most frequent genetic cause of Parkinson’s disease. Leucine-rich repeat kinase 2 variation related to susceptibility to disease displays many features that reflect the nature of complex late-onset sporadic disorders, such as Parkinson’s disease. The Genetic Epidemiology of Parkinson’s disease consortium recently performed the largest genetic association study for variants in the leucine-rich repeat kinase 2 gene across 23 different sites in 15 countries. Herein we detail the allele frequencies for the novel risk factors (p.A419V and p.M1646T) and the protective haplotype (p.N551K-R1398H-K1423K) reported in the original publication. Simple population allele frequencies can not only provide an insight into the clinical relevance of specific variants but also help genetically define patient groups. Establishing individual patient-based genomic susceptibility profiles incorporating both risk and protective factors will determine future diagnostic and treatment strategies. PMID:23913756

  7. 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

  8. Pontiac fever: an operational definition for epidemiological studies

    PubMed Central

    Tossa, Paul; Deloge-Abarkan, Magali; Zmirou-Navier, Denis; Hartemann, Philippe; Mathieu, Laurence

    2006-01-01

    Background Pontiac fever is usually described in epidemic settings. Detection of Pontiac fever is a marker of an environmental contamination by Legionella and should thereby call for prevention measures in order to prevent outbreak of Legionnaire's disease. The objective of this study is to propose an operational definition of Pontiac fever that is amenable to epidemiological surveillance and investigation in a non epidemic setting. Methods A population of 560 elderly subjects residing in 25 nursing homes was followed during 4 months in order to assess the daily incidence of symptoms associated, in the literature, with Pontiac fever. The water and aerosol of one to 8 showers by nursing home were characterized combining conventional bacterial culture of Legionella and the Fluorescence In Situ Hybridization (FISH) technique that used oligonucleotides probes specific for Legionellaceae. A definition of Pontiac fever was devised based on clinical symptoms described in epidemic investigations and on their timing after the exposure event. The association between incidence of Pontiac fever and shower contamination levels was evaluated to test the relevance of this definition. Results The proposed definition of Pontiac fever associated the following criteria: occurrence of at least one symptom among headache, myalgia, fever and shivers, possibly associated with other 'minor' symptoms, within three days after a shower contaminated by Legionella, during a maximum of 8 days (minimum 2 days). 23 such cases occurred during the study (incidence rate: 0.125 cases per person-year [95% CI: 0.122–0.127]). A concentration of Legionella in water equal to or greater than 104.L-1 (FISH method) was associated with a significant increase of incidence of Pontiac fever (p = 0.04). Conclusion Once validated in other settings, the proposed definition of Pontiac fever might be used to develop epidemiological surveillance and help draw attention on sources of Legionella. PMID:16646972

  9. New Saliva DNA Collection Method Compared to Buccal Cell Collection Techniques for Epidemiological Studies

    PubMed Central

    ROGERS, NIKKI L.; COLE, SHELLEY A.; LAN, HAO-CHANG; CROSSA, ALDO; DEMERATH, ELLEN W.

    2009-01-01

    Epidemiological studies may require noninvasive methods for off-site DNA collection. We compared the DNA yield and quality obtained using a whole-saliva collection device (Oragene™ DNA collection kit) to those from three established noninvasive methods (cytobrush, foam swab, and oral rinse). Each method was tested on 17 adult volunteers from our center, using a random crossover collection design and analyzed using repeated-measures statistics. DNA yield and quality were assessed via gel electrophoresis, spectophotometry, and polymerase chain reaction (PCR) amplification rate. The whole-saliva method provided a significantly greater DNA yield (mean ± SD = 154.9 ± 103.05 μg, median = 181.88) than the other methods (oral rinse = 54.74 ± 41.72 μg, 36.56; swab = 11.44 ± 7.39 μg, 10.72; cytobrush = 12.66 ± 6.19, 13.22 μg) (all pairwise P < 0.05). Oral-rinse and whole-saliva samples provided the best DNA quality, whereas cytobrush and swab samples provided poorer quality DNA, as shown by lower OD260/OD280 and OD260/OD230 ratios. We conclude that both a 10-ml oral-rinse sample and 2-ml whole-saliva sample provide sufficient DNA quantity and better quality DNA for genetic epidemiological studies than do the commonly used buccal swab and brush techniques. PMID:17421001

  10. New saliva DNA collection method compared to buccal cell collection techniques for epidemiological studies.

    PubMed

    Rogers, Nikki L; Cole, Shelley A; Lan, Hao-Chang; Crossa, Aldo; Demerath, Ellen W

    2007-01-01

    Epidemiological studies may require noninvasive methods for off-site DNA collection. We compared the DNA yield and quality obtained using a whole-saliva collection device (Oragene DNA collection kit) to those from three established noninvasive methods (cytobrush, foam swab, and oral rinse). Each method was tested on 17 adult volunteers from our center, using a random crossover collection design and analyzed using repeated-measures statistics. DNA yield and quality were assessed via gel electrophoresis, spectophotometry, and polymerase chain reaction (PCR) amplification rate. The whole-saliva method provided a significantly greater DNA yield (mean +/- SD = 154.9 +/- 103.05 microg, median = 181.88) than the other methods (oral rinse = 54.74 +/- 41.72 microg, 36.56; swab = 11.44 +/- 7.39 microg, 10.72; cytobrush = 12.66 +/- 6.19, 13.22 microg) (all pairwise P < 0.05). Oral-rinse and whole-saliva samples provided the best DNA quality, whereas cytobrush and swab samples provided poorer quality DNA, as shown by lower OD(260)/OD(280) and OD(260)/OD(230) ratios. We conclude that both a 10-ml oral-rinse sample and 2-ml whole-saliva sample provide sufficient DNA quantity and better quality DNA for genetic epidemiological studies than do the commonly used buccal swab and brush techniques. PMID:17421001

  11. [BIOETHICS LAWS AND REALITY ON THE GROUND DURING EPIDEMIOLOGICAL STUDIES IN FRENCH GUINEA AND CAMEROON].

    PubMed

    Tortevoye, Patricia; Gessain, Antoine

    2015-10-01

    The objective of this article is to describe the difficulties encountered, during the twenty last years, to obey the laws of bioethics in force during epidemiological investigations, carried out in French Guiana and in Cameroon. These research tasks aim to better understanding the transmission of two viruses: the human T lymphotropic retrovirus type 1 and the human herpes virus 8. These investigations, carried out in highly endemic villages, for one or two of these viruses, also aim at searching susceptibility genetic factors for infection in children by these viruses. They are scientific researches carried out in populations on low level of education and strong socio-economic constraints. These studies performed in general population are without benefit for the people. They require a collection of the family data, to build genealogic pedigrees, and a blood sampling. Using concrete examples, collected during field-investigations, we illustrate the problems encountered to apply, practically, the laws of bioethics. We will introduce and discuss thus the legislative framework in force, the studied populations, the concepts of preliminary information and informed consent, the adaptation necessary to take into account the local social organization and the importance of the family hierarchy. Lastly, the question of returned results of this kind of investigation will be discussed like that of the possible compensatory measures. This inventory reveals the limits of the current regulation, which is often poorly adapted to research in epidemiology in this kind of population and the ethical choices that has thus to be decided by the investigator. PMID:26911084

  12. 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. PMID:25597549

  13. Genetic studies of Crohn's disease: Past, present and future

    PubMed Central

    Liu, Jimmy Z.; Anderson, Carl A.

    2014-01-01

    The exact aetiology of Crohn's disease is unknown, though it is clear from early epidemiological studies that a combination of genetic and environmental risk factors contributes to an individual's disease susceptibility. Here, we review the history of gene-mapping studies of Crohn's disease, from the linkage-based studies that first implicated the NOD2 locus, through to modern-day genome-wide association studies that have discovered over 140 loci associated with Crohn's disease and yielded novel insights into the biological pathways underlying pathogenesis. We describe on-going and future gene-mapping studies that utilise next generation sequencing technology to pinpoint causal variants and identify rare genetic variation underlying Crohn's disease risk. We comment on the utility of genetic markers for predicting an individual's disease risk and discuss their potential for identifying novel drug targets and influencing disease management. Finally, we describe how these studies have shaped and continue to shape our understanding of the genetic architecture of Crohn's disease. PMID:24913378

  14. Invasive Streptococcus pneumoniae in France: Antimicrobial Resistance, Serotype, and Molecular Epidemiology Findings from a Monthly National Study in 2000 to 2002

    PubMed Central

    Decousser, Jean-Winoc; Pina, Patrick; Viguier, Florent; Picot, Franc; Courvalin, Patrice; Allouch, Pierre

    2004-01-01

    A study of 257 French invasive pneumococci isolated between 2000 and 2002 showed high rates of nonsusceptibility to penicillin and macrolides (50%), contrasting with a low frequency of resistance to amoxicillin or levofloxacin (<1%) and tolerance to vancomycin (0%). The genetic homogeneity of some serogroups, including serogroup 1, enhanced the risk of epidemiological changes. PMID:15328146

  15. Genetic, epidemiological and biological analysis of interleukin-10 promoter single-nucleotide polymorphisms suggests a definitive role for -819C/T in leprosy susceptibility.

    PubMed

    Pereira, A C; Brito-de-Souza, V N; Cardoso, C C; Dias-Baptista, I M F; Parelli, F P C; Venturini, J; Villani-Moreno, F R; Pacheco, A G; Moraes, M O

    2009-03-01

    Leprosy is a complex infectious disease influenced by genetic and environmental factors. The genetic contributing factors are considered heterogeneous and several genes have been consistently associated with susceptibility like PARK2, tumor necrosis factor (TNF), lymphotoxin-alpha (LTA) and vitamin-D receptor (VDR). Here, we combined a case-control study (374 patients and 380 controls), with meta-analysis (5 studies; 2702 individuals) and biological study to test the epidemiological and physiological relevance of the interleukin-10 (IL-10) genetic markers in leprosy. We observed that the -819T allele is associated with leprosy susceptibility either in the case-control or in the meta-analysis studies. Haplotypes combining promoter single-nucleotide polymorphisms also implicated a haplotype carrying the -819T allele in leprosy susceptibility (odds ratio (OR)=1.40; P=0.01). Finally, we tested IL-10 production in peripheral blood mononuclear cells stimulated with Mycobacterium leprae antigens and found that -819T carriers produced lower levels of IL-10 when compared with non-carriers. Taken together, these data suggest that low levels of IL-10 during the disease outcome can drive patients to a chronic and unprotective response that culminates with leprosy. PMID:19110537

  16. 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

  17. 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

  18. Prospects for Epigenetic Epidemiology

    PubMed Central

    Foley, Debra L.; Craig, Jeffrey M.; Morley, Ruth; Olsson, Craig J.; Dwyer, Terence; Smith, Katherine

    2009-01-01

    Epigenetic modification can mediate environmental influences on gene expression and can modulate the disease risk associated with genetic variation. Epigenetic analysis therefore holds substantial promise for identifying mechanisms through which genetic and environmental factors jointly contribute to disease risk. The spatial and temporal variance in epigenetic profile is of particular relevance for developmental epidemiology and the study of aging, including the variable age at onset for many common diseases. This review serves as a general introduction to the topic by describing epigenetic mechanisms, with a focus on DNA methylation; genetic and environmental factors that influence DNA methylation; epigenetic influences on development, aging, and disease; and current methodology for measuring epigenetic profile. Methodological considerations for epidemiologic studies that seek to include epigenetic analysis are also discussed. PMID:19139055

  19. 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

  20. Epidemiological study of prostate cancer (EPICAP): a population-based case–control study in France

    PubMed Central

    2014-01-01

    Background Prostate cancer is the most common cancer in male in most Western countries, including France. Despite a significant morbidity and mortality to a lesser extent, the etiology of prostate cancer remains largely unknown. Indeed, the only well-established risk factors to date are age, ethnicity and a family history of prostate cancer. We present, here, the rationale and design of the EPIdemiological study of Prostate CAncer (EPICAP), a population-based case–control study specifically designed to investigate the role of environmental and genetic factors in prostate cancer. The EPICAP study will particularly focused on the role of circadian disruption, chronic inflammation, hormonal and metabolic factors in the occurrence of prostate cancer. Methods/Design EPICAP is a population-based case–control study conducted in the département of Hérault in France. Eligible cases are all cases of prostate cancers newly diagnosed in 2012-2013 in men less than 75 years old and residing in the département of Hérault at the time of diagnosis. Controls are men of the same age as the cases and living in the département of Hérault, recruited in the general population. The sample will include a total of 1000 incident cases of prostate cancer and 1000 population-based controls over a 3-year period (2012-2014). The cases and controls are face-to-face interviewed using a standardized computed assisted questionnaire. The questions focus primarily on usual socio-demographic characteristics, personal and family medical history, lifestyle, leisure activities, residential and occupational history. Anthropometric measures and biological samples are also collected for cases and controls. Discussion The EPICAP study aims to answer key questions in prostate cancer etiology: (1) role of circadian disruption through the study of working hours, chronotype and duration/quality of sleep, (2) role of chronic inflammation and anti-inflammatory drugs, (3) role of hormonal and metabolic

  1. Critical review of epidemiologic studies related to ingested asbestos.

    PubMed Central

    Marsh, G M

    1983-01-01

    Thirteen epidemiologic studies of ingested asbestos conducted in five areas of the United States and Canada were reviewed and evaluated for the definitiveness and applicability regarding the development of ambient water quality standards. One or more studies found male or female associations between asbestos in water supplies and cancer mortality (or incidence) due to neoplasms of the esophagus, stomach, small intestine, colon, rectum, gallbladder, pancreas, peritoneum, lungs, pleura, prostate, kidneys, brain, and thyroid, and also due to leukemia. Several methodologic weaknesses and limitations were found in each study, leading to the determination that no individual study or aggregation of studies exist that would establish risk levels from ingested asbestos. A binomial probability analysis of the eight independent studies suggested that, while the level of male-female agreement was generally low, the number of observed positive associations in males and females for neoplasms of the esophagus, stomach, pancreas, and prostate was unlikely to have been generated by chance factors alone, and thus, may have a biological basis related to ingested asbestos. Cancers of the small intestine and leukemia were implicated to a lesser degree in this analysis. The patterns of integrated findings for most gastrointestinal cancers were somewhat consistent with patterns observed among asbestos-exposed occupational groups, whereas the patterns found for pancreatic cancer, kidney cancer, and leukemia were not consistent.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:6662094

  2. Overview of epidemiological studies on wine, health and mortality.

    PubMed

    Ruf, J C

    2003-01-01

    Numerous epidemiological studies have observed that moderate intake of alcohol including wine is associated with a lower risk of cardiovascular disease (CVD). However, according to several authors, moderate consumption of wine is more beneficial than that of beer or spirits. Some studies have shown that moderate consumption of wine can lower mortality from CVD and other causes. The link between drinking wine and total mortality risk (all causes combined) has been studied. The results of various prospective population studies show that intake of beer and spirits from abstention to light to moderate daily intake did not influence mortality, while wine seems to have a beneficial effect on all causes of mortality. Other studies have reached the same conclusion. In general, several authors have reported that in subjects consuming wine in moderation the risk of mortality from all causes is 20-30% lower than in abstainers. Grape wine appears to be the main alcoholic beverage that contains antioxidant phenolic substances known to inhibit oxidation of low-density lipoprotein and affect hemostasis and carcinogenesis. In conclusion, there are differences in the effects of wine, beer and spirits on health. These differences may not be significant in coronary heart disease. Only moderate wine consumption appears to have a beneficial effect on several types of cancer and on total mortality. PMID:15134372

  3. Endometriosis and breast cancer: A survey of the epidemiological studies

    PubMed Central

    PONTIKAKI, A.; SIFAKIS, S.; SPANDIDOS, D. A.

    2016-01-01

    Endometriosis is a chronic gynecological disease with a wide spectrum of clinical manifestations that affects approximately 10% of women of reproductive age. Recent reviews have demonstrated the connection between endometriosis and breast cancer, which represents the most frequently diagnosed female cancer and the most common cause of cancer-related mortality among women worldwide. The aim of this study was to conduct a survey of available published epidemiological studies indicating the association between endometriosis and breast cancer, and simultaneously to categorize the results based on the strength of the association, with the intention of the critical evaluation of the existing data. We performed a rigorous search of the PubMed/Medline database, using the key words ‘endometriosis’ and ‘breast cancer’ for all studies published in the English language until September 2015. We found 4 retrospective cohort studies, 4 case-control studies and 3 case-cohort studies that demonstrated a notable risk for developing breast cancer among women with endometriosis. By contrast, we also found 5 case-control studies, 1 prospective cohort study, 1 case-cohort study and 1 cross-sectional study that demonstrated a negative association between endometriosis and breast cancer. In conclusion, as regards the clarification of a ‘robust’ or ‘weak’ association between endometriosis and breast cancer, no definite conclusions could be drawn, due to the limited number of studies and the limitations of each of these studies. New well-designed, prospective cohort or randomized control trials with long-term follow-up are warranted in order to provide evidence-based clinical recommendations for proper counseling, screening and treatment strategies for patients with endometriosis, and hence to improve public health. PMID:26870162

  4. Mycosis fungoides in Iranian population: an epidemiological and clinicopathological study.

    PubMed

    Fatemi Naeini, Farahnaz; Abtahi-Naeini, Bahareh; Sadeghiyan, Hamidreza; Nilforoushzadeh, Mohammad Ali; Najafian, Jamshid; Pourazizi, Mohsen

    2015-01-01

    Background. Mycosis fungoides (MF) is the most common subtype of cutaneous T-cell lymphoma. Extensive studies on Iranian MF patients are absent. The present study aimed to produce updated clinical information on Iranian MF patients. Methods. This was a retrospective, descriptive, single-center study, including all cases of MF seen in the Department of Dermatology, University Hospital of Isfahan, Iran, between 2003 and 2013. Data systematically recorded for each patient included clinical, biological, histological, and molecular findings. Results. Eighty-six patients with clinical and histologic diagnosis of MF were included in the study. Thirty-nine patients (45.3%) were male. Female predominance was observed in patients (male : female ratio is 1 : 1.2). Patients were between 7 and 84 years of age (median: 41). The interval from disease onset to diagnosis ranged from 0 to 55 years (median: 1 year). Eighteen cases (20.9%) had unusual variants of MF. The most common types included hypopigmented and poikilodermatous MF. Childhood cases of MF constituted 5.8% (5/86) of all patients. The early stages were seen in 82 cases (95.34%). Conclusion. The major differences in epidemiologic characteristics of MF in Iran are the lack of male predominance and the lower age of patients at the time of diagnosis. PMID:25694829

  5. Mycosis Fungoides in Iranian Population: An Epidemiological and Clinicopathological Study

    PubMed Central

    Fatemi Naeini, Farahnaz; Abtahi-Naeini, Bahareh; Sadeghiyan, Hamidreza; Nilforoushzadeh, Mohammad Ali; Najafian, Jamshid; Pourazizi, Mohsen

    2015-01-01

    Background. Mycosis fungoides (MF) is the most common subtype of cutaneous T-cell lymphoma. Extensive studies on Iranian MF patients are absent. The present study aimed to produce updated clinical information on Iranian MF patients. Methods. This was a retrospective, descriptive, single-center study, including all cases of MF seen in the Department of Dermatology, University Hospital of Isfahan, Iran, between 2003 and 2013. Data systematically recorded for each patient included clinical, biological, histological, and molecular findings. Results. Eighty-six patients with clinical and histologic diagnosis of MF were included in the study. Thirty-nine patients (45.3%) were male. Female predominance was observed in patients (male : female ratio is 1 : 1.2). Patients were between 7 and 84 years of age (median: 41). The interval from disease onset to diagnosis ranged from 0 to 55 years (median: 1 year). Eighteen cases (20.9%) had unusual variants of MF. The most common types included hypopigmented and poikilodermatous MF. Childhood cases of MF constituted 5.8% (5/86) of all patients. The early stages were seen in 82 cases (95.34%). Conclusion. The major differences in epidemiologic characteristics of MF in Iran are the lack of male predominance and the lower age of patients at the time of diagnosis. PMID:25694829

  6. Epidemiological study of fixed drug eruption in Pointe-Noire.

    PubMed

    Ognongo-Ibiaho, A N; Atanda, H L

    2012-11-01

    A prospective study was conducted over a 27 month period in order to determine the epidemiological profile of fixed drug eruption (FDE) observed during a dermatological consultation at Pointe-Noire. During the study period 54 out of 9,070 persons consulting (0.6%) suffered from clinically diagnosed FDE. The variables studied were: age, sex, medicine and point of sale. The average age of onset was 30 years. The frequency of onset was higher in males (38 patients) than in females (16 patients). The incriminated medicines were: the sulfamides (48 patients) including Cotrimoxazole (45 patients ) and Sulfadoxine and Pyremethamine (3 patients) Coartem(®) + Doliprane(®) (1 patient), Chloramphenicol(®) (1 patient), Amidol(®) (1 patient), Duocotexin(®) + Paracetamol(®) (1 patient), Surquina(®) (1 patient), Amodiaquine(®) (1 patient). The point of sale was illicit (peddlers, markets) for 44 patients; for 10 patients it was a lawful outlet (pharmacies). This study shows that cotrimoxazole bought at illicit points of sale is the main etiology of FDE in the department, confirming that these medicines are counterfeit. The involvement of dermatologists in the fight against the illicit sale of medicines should be made a priority. PMID:23210952

  7. Chapter 8. Tea and Cancer Prevention: Epidemiological Studies

    PubMed Central

    Yuan, Jian-Min; Sun, Canlan; Butler, Lesley M.

    2011-01-01

    Experimental studies have consistently shown the inhibitory activities of tea extracts on tumorigenesis in multiple model systems. Epidemiologic studies, however, have produced inconclusive results in humans. A comprehensive review was conducted to assess the current knowledge on tea consumption and risk of cancers in humans. In general, consumption of black tea was not associated with lower risk of cancer. High intake of green tea was consistently associated with reduced risk of upper gastrointestinal tract cancers after sufficient control for confounders. Limited data support a protective effect of green tea on lung and hepatocellular carcinogenesis. Although observational studies do not support a beneficial role of tea intake on prostate cancer risk, phase II clinical trials have demonstrated an inhibitory effect of green tea extract against the progression of prostate pre-malignant lesions. Green tea may exert beneficial effects against mammary carcinogenesis in premenopausal women and recurrence of breast cancer. There is no sufficient evidence that supports a protective role of tea intake on the development of cancers of the colorectum, pancreas, urinary tract, glioma, lymphoma, and leukemia. Future prospective observational studies with biomarkers of exposure and phase III clinical trials are required to provide definitive evidence for the hypothesized beneficial effect of tea consumption on cancer formation in humans. PMID:21419224

  8. 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.

  9. 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...

  10. 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

  11. [Program of studies on psychiatric epidemiology in Argentina. General report].

    PubMed

    Casullo, M M

    1980-12-01

    This paper is an outline of a wide program that is currently under development in the large territory of Argentina. The Director of the Program is Dr. Fernando Pagés Larraya; it is supported by the National Council of Scientific Researches (CONICET) and the National Board of Mental Health. The general purpose of the program is to study the prevalence of mental disorders in different ethnographic areas within the country. Epidemiology allows the forecasting of disease occurence. A research work this area may be qualified "effective" if it provides useful data for prevention programs. Therefore, it is necessary that researches and professional responsibles of Mental Health Governmental decissions work together. This rapprochment is being attempted in developing the Argentine research program. It has a cross-cultural approach. It can be called "a way of thinking" as opposed to a precise methodology. A considerable variety of research tools are being used, depending on the specific purposes and the characteristics of the ethnographic areas. One of the main difficulties in choosing a technique for "case-finding" is uncertainty about where to place the "cut-off point" between presence and absence of illness. In this program the Present State Examination (PSE) is used in population surveys of large urban centers. It is a semi-structured interview that has been extensively tested. In small rural communities, the work is done using "key-informants" and applying the snow-ball sample technique. One specific purpose of the research is the study of the modal personality structure in each ethnographic area, formulated in terms of the Holtzman Inkblot Test. The paper shows the relationships between purposes, research tools and responsible professionals. There is hardly time or surplus intellectual energy for polemic and alienation between clinicians and social scientists. Theories, methodologies, research data and prevention programs have not developed harmoniously. We need to

  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. Interfacing anthropology and epidemiology: the Bedouin Arab Infant Feeding Study.

    PubMed

    Hundt, G A; Forman, M R

    1993-04-01

    This paper encapsulates a 10 year effort of multi-disciplinary research on the relationship between infant feeding, growth, and morbidity among the Negev Bedouin Arabs of Israel as they underwent a transition from semi-nomadism to urban settlement. The research team was multi-disciplinary including a nutritional epidemiologist and an anthropologist who both came to the study with previous experience in interdisciplinary work. The specific study objectives were (1) a description of infant feeding practices among Negev Bedouin Arab women at various stages of settlement, (2) an examination of the trend in these infant feeding practices, (3) a comparison of the extent to which different infant feeding practices are related to infant morbidity and growth after adjustment for exposure to social change and other covariates. The data collection took place in 1981-83 and the analysis from 1984-88. In this paper, two areas of the study are discussed in depth: the duration of exclusive breast feeding during the practice of the traditional postpartum 40 day rest period, and the development of a culture-specific scale of socioeconomic status. Through these examples, we highlight the use of ethnographic data and the merging of epidemiology and anthropology from hypothesis generation through data collection, data analysis and interpretation. PMID:8480241

  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. PMID:9449807

  16. Invited commentary: Personality phenotype and mortality--new avenues in genetic, social, and clinical epidemiology.

    PubMed

    Chapman, Benjamin P

    2013-09-01

    In this issue of the Journal, Jokela et al. (Am J Epidemiol. 2013;178(5):667-675) scrutinize the association between personality phenotype and all-cause mortality in remarkable detail by using an "individual-participant meta-analysis" design. Across 7 large cohorts varying in demographics and methods of personality measurement, they find varying prospective associations for 4 dimensions of the five-factor (or "Big Five") model of personality, but robust and consistent prospective associations for Big Five dimension of "conscientiousness." Jokela et al. place an important exclamation point on a long era of study of this topic and hint directly and indirectly at new avenues for this line of research. I consider the following 3 areas particularly rife for further inquiry: the role of genetics in personality and health studies; the role of personality in social inequalities in health; and the health policy and clinical implications of work like that of Jokela et al., including the potential role of personality phenotype in the evolution of personalized medicine. PMID:23911611

  17. Quantitative genetic studies of antisocial behaviour.

    PubMed

    Viding, Essi; Larsson, Henrik; Jones, Alice P

    2008-08-12

    This paper will broadly review the currently available twin and adoption data on antisocial behaviour (AB). It is argued that quantitative genetic research can make a significant contribution to further the understanding of how AB develops. Genetically informative study designs are particularly useful for investigating several important questions such as whether: the heritability estimates vary as a function of assessment method or gender; the relative importance of genetic and environmental influences varies for different types of AB; the environmental risk factors are truly environmental; and genetic vulnerability influences susceptibility to environmental risk. While the current data are not yet directly translatable for prevention and treatment programmes, quantitative genetic research has concrete translational potential. Quantitative genetic research can supplement neuroscience research in informing about different subtypes of AB, such as AB coupled with callous-unemotional traits. Quantitative genetic research is also important in advancing the understanding of the mechanisms by which environmental risk operates. PMID:18434281

  18. 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

  19. 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

  20. 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

  1. 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

  2. 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

  3. Maximizing DNA yield for epidemiologic studies: no more buffy coats?

    PubMed

    Gail, Mitchell H; Sheehy, Tim; Cosentino, Mark; Pee, David; Diaz-Mayoral, Norma A; Garcia-Closas, Montserrat; Caporaso, Neil E; Pitt, Karen; Ziegler, Regina G

    2013-10-01

    Some molecular analyses require microgram quantities of DNA, yet many epidemiologic studies preserve only the buffy coat. In Frederick, Maryland, in 2010, we estimated DNA yields from 5 mL of whole blood and from equivalent amounts of all-cell-pellet (ACP) fraction, buffy coat, and residual blood cells from fresh blood (n = 10 volunteers) and from both fresh and frozen blood (n = 10). We extracted DNA with the QIAamp DNA Blood Midi Kit (Qiagen Sciences, Germantown, Maryland) for silica spin column capture and measured double-stranded DNA. Yields from frozen blood fractions were not statistically significantly different from those obtained from fresh fractions. ACP fractions yielded 80.6% (95% confidence interval: 66, 97) of the yield of frozen whole blood and 99.3% (95% confidence interval: 86, 100) of the yield of fresh blood. Frozen buffy coat and residual blood cells each yielded only half as much DNA as frozen ACP, and the yields were more variable. Assuming that DNA yield and quality from frozen ACP are stable, we recommend freezing plasma and ACP. Not only does ACP yield twice as much DNA as buffy coat but it is easier to process, and its yield is less variable from person to person. Long-term stability studies are needed. If one wishes to separate buffy coat before freezing, one should also save the residual blood cell fraction, which contains just as much DNA. PMID:23857774

  4. Spatially Explicit Modeling of Schistosomiasis Risk in Eastern China Based on a Synthesis of Epidemiological, Environmental and Intermediate Host Genetic Data

    PubMed Central

    Schrader, Matthias; Hauffe, Torsten; Zhang, Zhijie; Davis, George M.; Jopp, Fred; Remais, Justin V.; Wilke, Thomas

    2013-01-01

    Schistosomiasis japonica is a major parasitic disease threatening millions of people in China. Though overall prevalence was greatly reduced during the second half of the past century, continued persistence in some areas and cases of re-emergence in others remain major concerns. As many regions in China are approaching disease elimination, obtaining quantitative data on Schistosoma japonicum parasites is increasingly difficult. This study examines the distribution of schistosomiasis in eastern China, taking advantage of the fact that the single intermediate host serves as a major transmission bottleneck. Epidemiological, population-genetic and high-resolution ecological data are combined to construct a predictive model capable of estimating the probability that schistosomiasis occurs in a target area (“spatially explicit schistosomiasis risk”). Results show that intermediate host genetic parameters are correlated with the distribution of endemic disease areas, and that five explanatory variables—altitude, minimum temperature, annual precipitation, genetic distance, and haplotype diversity—discriminate between endemic and non-endemic zones. Model predictions are correlated with human infection rates observed at the county level. Visualization of the model indicates that the highest risks of disease occur in the Dongting and Poyang lake regions, as expected, as well as in some floodplain areas of the Yangtze River. High risk areas are interconnected, suggesting the complex hydrological interplay of Dongting and Poyang lakes with the Yangtze River may be important for maintaining schistosomiasis in eastern China. Results demonstrate the value of genetic parameters for risk modeling, and particularly for reducing model prediction error. The findings have important consequences both for understanding the determinants of the current distribution of S. japonicum infections, and for designing future schistosomiasis surveillance and control strategies. The results

  5. Epidemiology and Genetic Diversity of Anaplasma phagocytophilum in the San Francisco Bay Area, California.

    PubMed

    Nieto, Nathan C; Salkeld, Daniel J

    2016-07-01

    In California, the agent of human granulocytic anaplasmosis (HGA), Anaplasma phagocytophilum, is transmitted by western black-legged ticks (Ixodes pacificus). Cases of HGA are infrequent in California but do occur annually. We investigated nymphal and adult western black-legged tick populations in 20 recreational areas in California's San Francisco Bay Area (Marin, Napa, San Mateo, Santa Clara, Santa Cruz, and Sonoma counties). Overall, prevalence of A. phagocytophilum in adult ticks was 0.8% (11/1,465), and in nymphal ticks was 4.2% (24/568), though presence was patchy and prevalence varied locally. We detected significant sequence variation in our quantitative polymerase chain reaction (qPCR)-positive samples. This included four sequences that grouped within a clade that contains clinical human and veterinary isolates as well as four others that grouped with sequences from PCR-positive lizards from northern California. Tick populations in our study sites harbor genetically diverse strains of A. phagocytophilum, which may influence potential risk in the region. PMID:27139447

  6. Epidemiology, genetic, natural history and clinical presentation of giant cerebral aneurysms.

    PubMed

    Lonjon, M; Pennes, F; Sedat, J; Bataille, B

    2015-12-01

    Giant cerebral aneurysms represent 5% of intracranial aneurysms, and become symptomatic between 40 and 70 years with a female predominance. In the paediatric population, the giant aneurysm rate is higher than in the adult population. Classified as saccular, fusiform and serpentine, the natural history of giant cerebral aneurysms is characterized by thrombosis, growth and rupture. The pathogenesis of these giant aneurysms is influenced by a number of risk factors, including genetic variables. Genome-wide association studies have identified some chromosomes highlighting candidate genes. Although these giant aneurysms can occur at the same locations as their smaller counterparts, a predilection for the cavernous location has been observed. Giant aneurysms present with symptoms caused by a mass effect depending on their location or by rupture; ischemic manifestations rarely reveal the aneurysm. If the initial clinical descriptions have been back up by imagery, the clinical context with a pertinent analysis of the risk factors remain the cornerstone for the management decisions of these lesions. Five year cumulative rupture rates for patients with giant aneurysm were 40% for those located on the anterior part of circle of Willis and 50% for those on the posterior part. The poor outcome of untreated patients justifies the therapeutic risks. PMID:26598391

  7. Quantitative trait loci on chromosome 8q24 for pancreatic beta-cell function and 7q11 for insulin sensitivity in obese nondiabetic white and black families: evidence from genome-wide linkage scans in the NHLBI Hypertension Genetic Epidemiology Network (HyperGEN) study.

    PubMed

    An, Ping; Freedman, Barry I; Rich, Stephen S; Mandel, Stephen A; Arnett, Donna K; Myers, Richard H; Chen, Yii-Der I; Hunt, Steven C; Rao, D C

    2006-02-01

    Genome-wide linkage scans were carried out using a multipoint variance components method in white and black families of the NHLBI Hypertension Genetic Epidemiology Network (HyperGEN) study to identify quantitative trait loci (QTLs) for pancreatic beta-cell function and insulin sensitivity estimated through the newly released nonlinear computer version of homeostasis model assessment 2. Participants fasting <8 h, with diagnosed type 2 diabetes, or taking blood glucose or blood lipid-lowering medications were excluded. Both phenotypes were adjusted separately by race and sex for the effects of age, BMI, and field center before linkage scans using 370 microsatellite markers were performed. A total of 685 white families (1,180 sibpairs) and 773 black families (775 sibpairs) were evaluated as well as subsets including 267 obese white families (757 sibpairs) and 427 obese black families (599 sibpairs) identified through tree-linkage analyses using interacting covariates of age, sex, and BMI. For beta-cell function in the obese white families, significant (logarithm of odds [LOD] score >3.6) evidence supporting linkages was detected on chromosome 8q24 at D8S1179 (135 cM, LOD score 4.2, empirical P = 0.002) and at D8S1128 (140 cM, LOD score 3.7, empirical P = 0.003). In addition, two regions supported linkage for insulin sensitivity index in the obese black families on chromosome 7q11 at D7S3046 (79 cM, LOD score 3.0, empirical P = 0.018) and on chromosome 6q26 at D6S1277 (173 cM, LOD score 3.0, empirical P = 0.018). Reducing clinical heterogeneity using obesity data and improved estimates of beta-cell function and insulin sensitivity may have permitted identification of a QTL on chromosome 8q24 for beta-cell function in the presence of estimated insulin resistance and a QTL on chromosome 7q11 for insulin sensitivity. These regions replicate previous reports for type 2 diabetes-associated traits. PMID:16443794

  8. 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

  9. Fatalities associated with farm tractor injuries: an epidemiologic study.

    PubMed

    Goodman, R A; Smith, J D; Sikes, R K; Rogers, D L; Mickey, J L

    1985-01-01

    Death certificates were used as a source of information to characterize fatalities associated with farm tractor injuries in Georgia for the period 1971-81. In this period, 202 tractor-associated fatalities occurred among residents of Georgia; 198 of these persons were males. The annual tractor-associated fatality rate for males based on the population of male farm residents was 23.6 per 100,000; rates of fatal injury increased with age for this population. Persons whose primary occupation was other than farming accounted for more than half of all tractor-associated deaths. Fatal injuries occurred throughout the year but predominantly during the planting and harvesting months. Injuries occurred throughout the day (7 a.m. to midnight), with a peak at 4 p.m. to 5 p.m. Most fatal injuries, 76 percent, resulted when tractors overturned. Fatalities were attributed to crushed chest, exsanguination, strangulation or asphyxia, drowning, and other injuries. Current safety standards for the operation of farm tractors are limited; rollover protective canopies are not required for farm owners or their family members. Descriptive epidemiologic information obtained from death certificates can be used to define injury determinants and to suggest approaches for the further study and prevention of specific types of injuries. PMID:3923543

  10. [Acute and overuse injuries in elite paracycling - an epidemiological study].

    PubMed

    Kromer, P; Röcker, K; Sommer, A; Baur, H; Konstantinidis, L; Gollhofer, A; Südkamp, N P; Hirschmüller, A

    2011-09-01

    Although paracycling is a growing discipline in high level competitive sports as well as in posttraumatic rehabilitation, epidemiological data of resulting injuries is still missing. Therefore, 19 athletes of the German national paracycling team were asked about their injuries during the 2008 season using a standardized questionnaire. Overall, 18 (94.7 %) of 19 athletes reported overuse injuries; most commonly localized at the back (83.3 %), neck/shoulder (77.8 %), knee (50 %), groin/buttock (50 %) and hands/wrists (38.9 %). Altogether, 18 accidents were registered, corresponding to an injury rate of 0,95 acute injuries per athlete per year (0,07 / 1000 km). The most common acute injuries were abrasions (69.2 %) and contusions (61.5 %), whereas fractures were stated only twice (11.8 %). The anatomical distribution of overuse injuries in disabled cyclists confirms the results of studies in able-bodied cycling, although the incidences in low-back pain and neck/shoulder pain is clearly higher in disabled cycling, as well as the rate of traumatic injuries. PMID:21922439

  11. Histopathologic reproducibility of thyroid disease in an epidemiologic study

    SciTech Connect

    Ron, E.; Griffel, B.; Liban, E.; Modan, B.

    1986-03-01

    An investigation of the long-term effects of childhood scalp irradiation demonstrated a significantly increased risk of thyroid tumors in the irradiated population. Because of the complexity of thyroid cancer diagnosis, a histopathologic slide review of 59 of the 68 patients (irradiated and nonirradiated) with thyroid disease was undertaken. The review revealed 90% agreement (kappa = +0.85, P less than 0.01) between the original and review diagnosis. Four of 27 cases previously diagnosed as malignant were reclassified as benign, yielding a cancer misdiagnosis rate of 14.8%. All four of the misdiagnosed cancers were of follicular or mixed papillary-follicular type. As a result of the histologic review, the ratio of malignant to benign tumors decreased from 2.55 to 1.75. Since disagreement in diagnosis was similar in the irradiated and nonirradiated groups, the relative risk of radiation-associated neoplasms did not change substantially. The histopathologic review shows that although there were some problems in diagnostic reproducibility, they were not statistically significant and did not alter our previous conclusions regarding radiation exposure. However, a 15% reduction in the number of malignancies might affect epidemiologic studies with an external comparison as well as geographic or temporal comparisons.

  12. 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…

  13. 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

  14. Epidemiology and genetic diversity of multidrug-resistant tuberculosis in East Africa

    PubMed Central

    Kidenya, Benson R.; Webster, Lauren E.; Behan, Sehan; Kabangila, Rodrick; Peck, Robert N.; Mshana, Stephen E.; Ocheretina, Oksana; Fitzgerald, Daniel W.

    2013-01-01

    SUMMARY Multidrug-resistant tuberculosis (MDR-TB) is an emerging problem in many parts of the world, and levels of MDR-TB among new TB patients are increasing in sub-Saharan Africa. We reviewed the prevalence and molecular epidemiology of MDR-TB in East Africa, including Burundi, Kenya, Rwanda, Tanzania, and Uganda. In 16 epidemiologic surveys, the prevalence of MDR among new cases ranges from 0.4% in Tanzania to 4.4% in Uganda, and among recurrent cases ranges from 3.9% in Tanzania to 17.7% in Uganda. There is a gap of 5,948 cases between the estimated number of MDR-TB cases in East Africa and the number actually diagnosed. The only confirmed risk factors for MDR-TB are prior treatment for TB and refugee status. HIV has not been reported as a risk factor, and there are no reports of statistical association between spoligotype and drug resistance pattern. Increased capacity for diagnosis and treatment of MDR-TB is needed, with an emphasis on recurrent TB cases and refugees. PMID:24215798

  15. 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...

  16. 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.

  17. Molecular Epidemiology and Genetic Diversity of Echovirus Type 30 (E30): Genotypes Correlate with Temporal Dynamics of E30 Isolation

    PubMed Central

    Oberste, M. Steven; Maher, Kaija; Kennett, Margery L.; Campbell, Janice J.; Carpenter, Michael S.; Schnurr, David; Pallansch, Mark A.

    1999-01-01

    Echovirus type 30 (E30) (genus, Enterovirus; family, Picornaviridae) has caused large outbreaks of aseptic meningitis in many regions of the world in the last 40 years. U.S. enterovirus surveillance data for the period 1961 to 1998 indicated that the annual proportion of E30 isolations relative to total enterovirus isolations has fluctuated widely, from a low of 0% in 1966 to a high of 42% in 1998. Peaks of E30 isolations occurred in the years 1968 to 1969, 1981 to 1984, 1990 to 1993, and 1997 to 1998, coincident with large nationwide outbreaks of E30-associated aseptic meningitis. Analysis of the complete VP1 sequence (876 nucleotides) of 136 E30 strains isolated in geographically dispersed regions of the United States and nine other countries between 1956 and 1998 indicated that the currently circulating E30 strains are genetically distinct from those isolated 30 to 40 years ago. Phylogenetic reconstruction demonstrated the existence of at least four distinct genetic groups, three of which have not been isolated in North America since 1981. Two of the three groups disappeared during periods when E30 was isolated infrequently. All North American E30 strains isolated after 1988 were closely related to one another, and all post-1993 isolates were of the same lineage within this group. Surveillance data indicate that E30 causes large national outbreaks of 2- to 4-year durations, separated by periods of relative quiescence. Our results show that shifts in the overall genetic diversity of E30 and the predominant genetic type correlate temporally with the dynamics of E30 isolation. The sequence data also provide a basis for the application of molecular techniques for future epidemiologic investigations of E30 disease. PMID:10565909

  18. An epidemiological study of RSV infection in the Gambia.

    PubMed Central

    Weber, Martin W.; Milligan, Paul; Sanneh, Mariama; Awemoyi, Agnes; Dakour, Raduwan; Schneider, Gisela; Palmer, Ayo; Jallow, Mariatou; Oparaogu, Anslem; Whittle, Hilton; Mulholland, E. Kim; Greenwood, Brian M.

    2002-01-01

    OBJECTIVE: To describe the epidemiology of respiratory syncytial virus (RSV) infection in a developing country. METHODS: The work was carried out in three hospitals for primary cases and in the community for secondary cases in the western region of the Gambia, West Africa. RSV infection was diagnosed by immunofluorescence of nasopharyngeal aspirate samples in children younger than two years admitted to hospital with acute lower respiratory infection (ALRI). Routine records of all children with ALRI were analysed, and the incidence rates of ALRI, severe RSV-associated respiratory illness and hypoxaemic RSV infections were compared. A community-based study was undertaken to identify secondary cases and to obtain information about spread of the virus. FINDINGS: 4799 children with ALRI who were younger than two years and lived in the study area were admitted to the study hospitals: 421 had severe RSV-associated respiratory illness; 55 of these were hypoxaemic. Between 1994 and 1996, the observed incidence rate for ALRI in 100 children younger than one year living close to hospital was 9.6 cases per year; for severe RSV-associated respiratory illness 0.83; and for hypoxaemic RSV-associated respiratory illness 0.089. The proportion of all ALRI admissions due to RSV was 19%. Overall, 41% of children younger than five years in compounds in which cases lived and 42% in control compounds had evidence of RSV infection during the surveillance period. CONCLUSION: RSV is an important cause of ALRI leading to hospital admission in the Gambia. Morbidity is considerable and efforts at prevention are worthwhile. PMID:12163920

  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. PMID:27128094

  20. 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

  1. A molecular epidemiological study of rabies epizootics in kudu (Tragelaphus strepsiceros) in Namibia

    PubMed Central

    Mansfield, Karen; McElhinney, Lorraine; Hübschle, Otto; Mettler, Felix; Sabeta, Claude; Nel, Louis H; Fooks, Anthony R

    2006-01-01

    Background A panel of 37 rabies virus isolates were collected and studied, originating mainly from the northern and central regions of Namibia, between 1980 and 2003. Results These virus isolates demonstrated a high degree of genetic similarity with respect to a 400 bp region of the nucleoprotein gene, with the virus isolates originating from kudu antelope (n = 10) sharing 97.2–100% similarity with jackal isolates, and 97–100% similarity with those isolated from domestic dogs. Phylogenetic analysis suggested that these viruses were all of the canid rabies biotype of southern Africa. The viruses from kudu were closely associated with jackal isolates (n = 6), bat-eared fox isolates (n = 2) and domestic dog isolates (n = 2) at the genetic level and identical at the amino acid level, irrespective of the year of isolation. Conclusion These data suggest that jackal and kudu may form part of the same epidemiological cycle of rabies in Namibian wildlife, and might demonstrate the close-relationship between rabies virus strains that circulate within Namibia and those that circulate between Namibia and its neighbouring countries such as Botswana and South Africa. PMID:16412222

  2. 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

  3. [Epidemiology, origin and genetic diversity of HTLV-1 retrovirus and STLV-1 simian affiliated retrovirus].

    PubMed

    Gessain, A; Mahieux, R

    2000-07-01

    Human T Cell leukemia/lymphoma virus type I, the first human oncogenic retrovirus, is the aetiological factor of Adult T cell leukemia (ATL), a CD4+ malignant lymphoproliferative disease and of a chronic neuromyelopathy, the tropical spastic paraparesis or HTLV-1 associated myelopathy (TSP/HAM). HTLV-1, which infects from 15 to 25 million individuals world-wide, is highly endemic in certain areas such as south-western Japan, Central Africa, the Caribbean basin and some regions of South America, Melanesia and of the middle East (for example the Mashhad area of Iran). The three major modes of transmission for HTLV-1 infection are perinatal, sexual and by blood transfusion. Recent molecular studies on HTLV-1 have shown the existence of several molecular subtypes (genotypes). These are related to the geographical origin of the infected populations and not to the associated diseases. The virus has a very high genetic stability. Viral amplification via clonal expansion of infected cells, rather than by use of reverse transcription could explain this remarkable phenomenon which can be used as a molecular tool for gaining new insights into the origin, evolution and modes of dissemination of HTLV-1. Analyses of HTLV-1 and STLV-1 (the simian counterpart) viral strains from throughout the world suggest that four events are responsible for this pattern of dissemination: 1) the transmission in the wild of STLV-1 between simian species, 2) the transmission of STLV-1 to humans as exemplified by the high percentage of identity between STLV-1 strains from chimpanzees or from mandrills with some HTLV-1 strains present in inhabitants of Central Africa, 3) persistence of HTLV-1 over a long period of time (by sexual and perinatal transmissions) in remote populations, as seen in the Australo-Melanesian region and 4) a global distribution of HTLV-1 via large scale human migrations, e.g., the slave trade from Africa to the New World. PMID:11030050

  4. 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

  5. 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...

  6. New Insights into Handling Missing Values in Environmental Epidemiological Studies

    PubMed Central

    Roda, Célina; Nicolis, Ioannis; Momas, Isabelle; Guihenneuc, Chantal

    2014-01-01

    Missing data are unavoidable in environmental epidemiologic surveys. The aim of this study was to compare methods for handling large amounts of missing values: omission of missing values, single and multiple imputations (through linear regression or partial least squares regression), and a fully Bayesian approach. These methods were applied to the PARIS birth cohort, where indoor domestic pollutant measurements were performed in a random sample of babies' dwellings. A simulation study was conducted to assess performances of different approaches with a high proportion of missing values (from 50% to 95%). Different simulation scenarios were carried out, controlling the true value of the association (odds ratio of 1.0, 1.2, and 1.4), and varying the health outcome prevalence. When a large amount of data is missing, omitting these missing data reduced statistical power and inflated standard errors, which affected the significance of the association. Single imputation underestimated the variability, and considerably increased risk of type I error. All approaches were conservative, except the Bayesian joint model. In the case of a common health outcome, the fully Bayesian approach is the most efficient approach (low root mean square error, reasonable type I error, and high statistical power). Nevertheless for a less prevalent event, the type I error is increased and the statistical power is reduced. The estimated posterior distribution of the OR is useful to refine the conclusion. Among the methods handling missing values, no approach is absolutely the best but when usual approaches (e.g. single imputation) are not sufficient, joint modelling approach of missing process and health association is more efficient when large amounts of data are missing. PMID:25226278

  7. New insights into handling missing values in environmental epidemiological studies.

    PubMed

    Roda, Célina; Nicolis, Ioannis; Momas, Isabelle; Guihenneuc, Chantal

    2014-01-01

    Missing data are unavoidable in environmental epidemiologic surveys. The aim of this study was to compare methods for handling large amounts of missing values: omission of missing values, single and multiple imputations (through linear regression or partial least squares regression), and a fully Bayesian approach. These methods were applied to the PARIS birth cohort, where indoor domestic pollutant measurements were performed in a random sample of babies' dwellings. A simulation study was conducted to assess performances of different approaches with a high proportion of missing values (from 50% to 95%). Different simulation scenarios were carried out, controlling the true value of the association (odds ratio of 1.0, 1.2, and 1.4), and varying the health outcome prevalence. When a large amount of data is missing, omitting these missing data reduced statistical power and inflated standard errors, which affected the significance of the association. Single imputation underestimated the variability, and considerably increased risk of type I error. All approaches were conservative, except the Bayesian joint model. In the case of a common health outcome, the fully Bayesian approach is the most efficient approach (low root mean square error, reasonable type I error, and high statistical power). Nevertheless for a less prevalent event, the type I error is increased and the statistical power is reduced. The estimated posterior distribution of the OR is useful to refine the conclusion. Among the methods handling missing values, no approach is absolutely the best but when usual approaches (e.g. single imputation) are not sufficient, joint modelling approach of missing process and health association is more efficient when large amounts of data are missing. PMID:25226278

  8. True Vertigo Patients in Emergency Department; an Epidemiologic Study

    PubMed Central

    Shahrami, Ali; Norouzi, Mehdi; Kariman, Hamid; Hatamabadi, Hamid Reza; Arhami Dolatabadi, Ali

    2016-01-01

    Introduction: Vertigo prevalence is estimated to be 1.8% among young adults and more than 30% in the elderly. 13-38% of the referrals of patients over 65 years old in America are due to vertigo. Vertigo does not increase the risk of mortality but it can affect the patient’s quality of life. Therefore, this study was designed to evaluate the epidemiologic characteristics of vertigo patients referred to the emergency department (ED). Methods: In this 6-month retrospective cross-sectional study, the profiles of all vertigo patients referred to the ED of Imam Hossein Hospital, Tehran, Iran, from October 2013 to March 2014 were evaluated. Demographic data and baseline characteristics of the patients were recorded and then patients were divided into central and peripheral vertigo. The correlation of history and clinical examination with vertigo type was evaluated and screening performance characteristics of history and clinical examination in differentiating central and peripheral vertigo were determined. Results: 379 patients with the mean age of 50.69 ± 11.94 years (minimum 18 and maximum 86) were enrolled (58.13% female). There was no sex difference in vertigo incidence (p = 0.756). A significant correlation existed between older age and increase in frequency of central cases (p < 0.001). No significant difference was detected between the treatment protocols regarding ED length of stay (p = 0.72). There was a significant overlap between the initial diagnosis and the final decision based on imaging and neurologist’s final opinion (p < 0.001). In the end, 361 (95.3%) patients were discharged from ED, while 18 were disposed to the neurology ward. No case of mortality was reported. Conclusion: Sensitivity and specificity of history and clinical examination in differentiating central and peripheral vertigo were 99 (95% CI: 57-99) and 99 (95% CI: 97-99), respectively PMID:26862546

  9. 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...

  10. PROSPECTIVE EPIDEMIOLOGICAL STUDY OF ENTERIC DISEASE TRANSMISSION ASSOCIATED WITH SPRINKLER IRRIGATION WITH WASTEWATER: AN OVERVIEW

    EPA Science Inventory

    The report deals with a prospective epidemiological morbidity and serology study, in which the quality of data could be optimally controlled on the possible association between enteric disease incidence and wastewater utilization in agricultural settlements in Israel. The study r...

  11. 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...

  12. Feasibility of future epidemiological studies on possible health effects of mobile phone base stations.

    PubMed

    Neubauer, Georg; Feychting, Maria; Hamnerius, Yngve; Kheifets, Leeka; Kuster, Niels; Ruiz, Ignacio; Schüz, Joachim; Uberbacher, Richard; Wiart, Joe; Röösli, Martin

    2007-04-01

    The increasing deployment of mobile communication base stations led to an increasing demand for epidemiological studies on possible health effects of radio frequency emissions. The methodological challenges of such studies have been critically evaluated by a panel of scientists in the fields of radiofrequency engineering/dosimetry and epidemiology. Strengths and weaknesses of previous studies have been identified. Dosimetric concepts and crucial aspects in exposure assessment were evaluated in terms of epidemiological studies on different types of outcomes. We conclude that in principle base station epidemiological studies are feasible. However, the exposure contributions from all relevant radio frequency sources have to be taken into account. The applied exposure assessment method should be piloted and validated. Short to medium term effects on physiology or health related quality of life are best investigated by cohort studies. For long term effects, groups with a potential for high exposure need to first be identified; for immediate effect, human laboratory studies are the preferred approach. PMID:17080459

  13. 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.

  14. 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.

  15. 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…

  16. 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...

  17. 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.

  18. What is desirable and feasible in dose reconstruction for application in epidemiological studies?

    SciTech Connect

    Bouville, A.; Beebe, G.W.; Anspaugh, L.

    1996-02-01

    Epidemiological studies of populations are of two general forms, monitoring or formal, and serve several possible purposes. Monitoring studies inform members of potentially affected population groups of the nature and magnitude of the risks that might have been imposed on them. Formal epidemiological studies can increase scientific knowledge about the quantitative risk that attends exposure. Risks of human health due to radiation exposure are most appropriately estimated by means of formal epidemiological studies. Dosimetric data are essential for any epidemiological study, but the detail and accuracy needed depend on the purposes to be served. If the need is for a monitoring study, then general information about doses will suffice. However, a formal study that is expected to contribute to scientific information about quantitative radiation risk requires careful individual dose estimation. This paper is devoted to the discussion of dosimetric data needed for formal epidemiological studies of populations exposed as a result of nuclear power operations. The recommendations made by the National Research Council have largely been followed. The examples used in this paper are relevant to the Chernobyl accident, which caused a large number of people to be exposed at relatively high doses and provided an opportunity for formal epidemiological studies to be initiated. The studies that are singled out are those of thyroid cancer among children who resided in Belarus and in Ukraine at the time of the accident, and those of leukemia among workers involved in the mitigation of the accident and in clean-up operations.

  19. [Epidemiological study of tinea pedis in a population studied in Santa Casa de Sao Paulo].

    PubMed

    Zaitz, C; Proença, N G

    1989-01-01

    The authors make an epidemiologic study of tinea pedis aiming at establishing its minimal frequency in the population studied, as well as recognizing the most frequent fungi and the clinical aspects they determine. We've tried to study the role of the dermatophytes in the normal microbiota of the feet. Finally we analyzed the influence of sex and seasonality factors on the incidence of tinea pedis. PMID:2693864

  20. The leukemias: Epidemiologic aspects

    SciTech Connect

    Linet, M.S.

    1984-01-01

    Particularly geared to physicians and cancer researchers, this study of the epidemiology and etiology of leukemia analyzes the four major leukemia subtypes in terms of genetic and familial determinant factors and examines the incidence, distribution and frequency of reported leukemia clusters. Linet discusses the connection between other types of malignancies, their treatments, and the subsequent development of leukemia and evaluates the impact on leukemia onset of such environmental factors as radiation therapy, drugs, and occupational hazards.

  1. Genetic diversity of Bacillus anthracis in Europe: genotyping methods in forensic and epidemiologic investigations.

    PubMed

    Derzelle, Sylviane; Thierry, Simon

    2013-09-01

    Bacillus anthracis, the etiological agent of anthrax, a zoonosis relatively common throughout the world, can be used as an agent of bioterrorism. In naturally occurring outbreaks and in criminal release of this pathogen, a fast and accurate diagnosis is crucial to an effective response. Microbiological forensics and epidemiologic investigations increasingly rely on molecular markers, such as polymorphisms in DNA sequence, to obtain reliable information regarding the identification or source of a suspicious strain. Over the past decade, significant research efforts have been undertaken to develop genotyping methods with increased power to differentiate B. anthracis strains. A growing number of DNA signatures have been identified and used to survey B. anthracis diversity in nature, leading to rapid advances in our understanding of the global population of this pathogen. This article provides an overview of the different phylogenetic subgroups distributed across the world, with a particular focus on Europe. Updated information on the anthrax situation in Europe is reported. A brief description of some of the work in progress in the work package 5.1 of the AniBioThreat project is also presented, including (1) the development of a robust typing tool based on a suspension array technology and multiplexed single nucleotide polymorphisms scoring and (2) the typing of a collection of DNA from European isolates exchanged between the partners of the project. The know-how acquired will contribute to improving the EU's ability to react rapidly when the identity and real origin of a strain need to be established. PMID:23971802

  2. [Epidemiologic warnings from studies on alcohol use disorders].

    PubMed

    Limosin, F

    2014-04-01

    The highest consumption levels of alcohol are found in the developed world, mostly the Northern Hemisphere. After a slight decrease at the beginning of the 1990s, alcohol use in the European Region increased with an average adult per capita consumption amounting to 12.5 litres of pure alcohol per capita for the year 2009. In France, adult consumption was 12.7 litres of pure alcohol per capita for the year 2009, and it is estimated that 1.5 to 2 million of adults are alcohol-dependent (4-5% of the adult population) and 5 million are excessive drinkers. The harmful use of alcohol is one of the world's leading health risks. Alcohol is the direct cause of more than 30 diseases and a causal factor in more than 60 major types of diseases and injuries, resulting in approximately 2.5 million deaths each year. Approximately 4% of all deaths worldwide and 4.5% (7.4% for men and 1.4% for women) of the global burden of disease and injury are attributable to alcohol. In 2004 in the EU, 15.2% of all disability-adjusted life years (DALYs) in men and 3.9% of all DALYs in women were lost due to alcohol. While the impact of alcohol consumption and dependence on mortality and disease is substantial, there are also many psychosocial consequences, including violence, family problems, child neglect and abuse, absenteeism and lost productivity in the workplace. This means that alcohol consumption and dependence have sizable impacts on many people other than the drinker. These effects add up to a staggering number of alcohol-attributable social costs, which can be estimated at € 155.8 billion a year in Europe. Despite all these consequences, many individuals with alcohol use disorders remain untreated although effective treatments exist. From 37 community-based psychiatric epidemiology studies that used standardized diagnostic instruments and included data on the percentage of individuals receiving care for alcohol abuse or dependence, the median rate of untreated cases of these

  3. 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 ...

  4. 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...

  5. TRANSMISSION OF ENTERIC DISEASE ASSOCIATED WITH WASTEWATER IRRIGATION: A PROSPECTIVE EPIDEMIOLOGICAL STUDY

    EPA Science Inventory

    We conducted a prospective epidemiological study of possible enteric disease transmission by aerosolized pathogens from sprinkler irrigation of partially treated wastewater in 20 kibbutzim (colllective agricultural settlements) in Isreal between March 1981 and February 1982. Medi...

  6. 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...

  7. 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...

  8. 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...

  9. 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

  10. 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

  11. Molecular Epidemiology and Genetic Characteristics of Various blaPER Genes in Shanghai, China.

    PubMed

    Xie, Lianyan; Wu, Jun; Zhang, Fangfang; Han, Lizhong; Guo, Xiaokui; Ni, Yuxing; Sun, Jingyong

    2016-06-01

    We describe the genetic characteristics and possible transmission mechanism of blaPER in 25 clinical Gram-negative bacilli in Shanghai. blaPER, including blaPER-1, blaPER-3, and blaPER-4, was located chromosomally or in different plasmids. Tn1213 harboring blaPER-1 was first identified in two Proteus mirabilis isolates in China. The other blaPER variants were preceded by an ISCR1 element inside the complex class 1 integron associated with IS26, Tn21, Tn1696, and a miniature inverted-repeat transposable element. PMID:27067315

  12. 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

  13. 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. PMID:26647395

  14. Strategies to work with HLA data in human populations for histocompatibility, clinical transplantation, epidemiology and population genetics: HLA-NET methodological recommendations.

    PubMed

    Sanchez-Mazas, A; Vidan-Jeras, B; Nunes, J M; Fischer, G; Little, A-M; Bekmane, U; Buhler, S; Buus, S; Claas, F H J; Dormoy, A; Dubois, V; Eglite, E; Eliaou, J F; Gonzalez-Galarza, F; Grubic, Z; Ivanova, M; Lie, B; Ligeiro, D; Lokki, M L; da Silva, B Martins; Martorell, J; Mendonça, D; Middleton, D; Voniatis, D Papioannou; Papasteriades, C; Poli, F; Riccio, M E; Vlachou, M Spyropoulou; Sulcebe, G; Tonks, S; Nevessignsky, M Toungouz; Vangenot, C; van Walraven, A-M; Tiercy, J-M

    2012-12-01

    HLA-NET (a European COST Action) aims at networking researchers working in bone marrow transplantation, epidemiology and population genetics to improve the molecular characterization of the HLA genetic diversity of human populations, with an expected strong impact on both public health and fundamental research. Such improvements involve finding consensual strategies to characterize human populations and samples and report HLA molecular typings and ambiguities; proposing user-friendly access to databases and computer tools and defining minimal requirements related to ethical aspects. The overall outcome is the provision of population genetic characterizations and comparisons in a standard way by all interested laboratories. This article reports the recommendations of four working groups (WG1-4) of the HLA-NET network at the mid-term of its activities. WG1 (Population definitions and sampling strategies for population genetics' analyses) recommends avoiding outdated racial classifications and population names (e.g. 'Caucasian') and using instead geographic and/or cultural (e.g. linguistic) criteria to describe human populations (e.g. 'pan-European'). A standard 'HLA-NET POPULATION DATA QUESTIONNAIRE' has been finalized and is available for the whole HLA community. WG2 (HLA typing standards for population genetics analyses) recommends retaining maximal information when reporting HLA typing results. Rather than using the National Marrow Donor Program coding system, all ambiguities should be provided by listing all allele pairs required to explain each genotype, according to the formats proposed in 'HLA-NET GUIDELINES FOR REPORTING HLA TYPINGS'. The group also suggests taking into account a preliminary list of alleles defined by polymorphisms outside the peptide-binding sites that may affect population genetic statistics because of significant frequencies. WG3 (Bioinformatic strategies for HLA population data storage and analysis) recommends the use of programs capable

  15. 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

  16. [Exposure to endocrine disrupting chemicals and children's health: problems in epidemiological studies].

    PubMed

    Kishi, Reiko; Sata, Fumihiro; Saijo, Yasuaki; Kurahashi, Norie; Kato, Shizue; Nakajima, Sonomi; Sasaki, Seiko

    2006-01-01

    Most endocrine disrupting chemicals are characterized by their properties to induce marked phenotypic changes in offspring such as congenital anomalies and neurodevelopmental dysfunctions. Although an increase in the prevalence of hypospadias or cryptorchidism has been reported in various countries, improvement in diagnostic techniques and more attention to the features of the diseases have also been emphasized. Although there have been a few reports that hypospadias or cryptorchidism had been associated with diethylstilbestrol (DES), pesticides and so on, the associations between these diseases and endocrine disrupting chemicals remain unclear. Recently, the association between maternal metabolic polymorphism or paternal smoking during pregnancy and these diseases has been reported. There are also variable clinical features in children's neurobehavioral development, and thyroid and immune functions in relation to exposure to endocrine disrupting chemicals such as polychlorinated biphenyls (PCBs) and dioxins. Only a few Dutch studies have suggested that perinatal exposure to background level of PCB/dioxin confers immunity to allergy development. Genetic susceptibility to environmental endocrine disrupting chemicals may be related to adverse pregnancy outcomes. It is suggested that well-designed epidemiological studies such as prospective cohort studies should be performed to elucidate this association. PMID:16506651

  17. Clinical epidemiology of gastric cancer in Hehuang valley of China: A 10-year epidemiological study of gastric cancer

    PubMed Central

    Yan, Su; Li, Bin; Bai, Zhen-Zhong; Wu, Jun-Qi; Xie, Da-Wei; Ma, Ying-Cai; Ma, Xu-Xiang; Zhao, Jun-Hui; Guo, Xin-Jian

    2014-01-01

    AIM: To investigate the clinical epidemiological characteristics of gastric cancer in the Hehuang valley, China, to provide a reference for treatment and prevention of regional gastric cancer. METHODS: Between February 2003 and February 2013, the records of 2419 patients with gastric cancer were included in this study. The patient’s characteristics, histological and pathological features, as well as the dietary habits of the patients, were investigated. RESULTS: The clinical data showed that adenocarcinoma was the leading histological type of gastric cancer in this area. Characteristics of gastric cancer in different ethnic groups and age showed that the 60.55-65.50 years group showed the high incidence of gastric cancer in all ethnic groups. There were more male gastric cancer patients than female. Intestinal was the most common type of gastric cancer in the Hehuang valley. There was no significant difference in the proportion of sex in terms of Helicobacter pylori infection. The impact of dietary habits on gastric cancer showed that regular consumption of fried or grilled food, consumption of high-salt, high-fat and spicy food and drinking strong Boiled brick-tea were three important factors associated with gastric cancer in males and females. CONCLUSION: Differences existed in race, sex, and age of patients according to the epidemiology of gastric cancer in the Hehuang valley. Moreover, dietary habits was also an important factor contributing to gastric cancer. PMID:25132766

  18. 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

  19. 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

  20. Environmental index in genetic epidemiology: an investigation of its role, adequacy, and limitations.

    PubMed Central

    Rao, D C; Wette, R

    1990-01-01

    The concept of environmental index is briefly reviewed. With a biologically plausible theoretical model, the consequences of indices being based on incomplete information about the familial environment are investigated. It is shown that using partial indices on all family members leads to both an underestimation of the familial environmental component of variance, also called cultural heritability, and, although to a possibly lesser extent, an overestimation of the genetic heritability. It is further shown that so long as complete indices are available on both parents, using identically partial indices on children will yield nearly undistorted parameter estimates. These conclusions were arrived at by using a special case of the model and may not apply in general. PMID:2294748

  1. 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

  2. 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

  3. 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

  4. [Nontuberculous mycobacteriosis; the present status of epidemiology and clinical studies].

    PubMed

    Sakatani, M

    1999-04-01

    In Japan, The Mycobacteriosis Research Group at the Japanese National Chest Hospitals has continuously made the clinico-epidemiological study of nontuberculous mycobacteriosis (NTM) since early 1970s. The prevalence rate was determined as 0.82, 0.91, 1.22, 1.74 and 2.43 per 100,000 population per year in 1971, 1975, 1980, 1985 and in 1990 respectively. The newest datum in 1997 was 3.52. These data indicates the prevalence rate has continuously increased and became 3.8 times than 25 years ago. While on the other hand, the prevalence rate of lung tuberculosis has decreased from 133.1 to 15.2, becoming one nines in the same period. The numbers of newly detected patients of lung mycobacteriosis in 1996 were also studied at 12 hospitals in Kinki district. The rate of NTM was 16.6% in 4 sanatorium hospitals, being about the same to the datum of The Mycobacteriosis Research Group. The rate of NTM in 8 general hospitals was surprisingly high, 40.0%. The 70% of NTM patients were infected with Mycobacterium avium complex (MAC). The 24% were with M. kansasii, and the only 6% were with other miscellaneous species. That is, the about one thirds or more of total NTM patients were female MAC desease patients, another one thirds or less were male MAC patients, and the more than 90% of M. kansasii patients (about one fourth of total patients) were male. These 3 groups took the most part of NTM patients. The rate of female MAC patients with small non-cavitary lesion without underlying diseases showed a tendency to increase, and the rate of male MAC patients with cavitary lesions with underlying lung or systemic diseases decreased. In 1997, American Thoracic Society (ATS) published the official statement about the diagnosis and treatment of NTM disease. The table-1 in that statement showed the new criteria for diagnosis of NTM pulmonary disease. It is useful for precise diagnosis of lung NTM disease, and the old criteria made by The Mycobacteriosis Research Group of the Japanese

  5. 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

  6. 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

  7. Late Language Emergence at 24 Months: An Epidemiological Study of Prevalence, Predictors, and Covariates

    PubMed Central

    Zubrick, Stephen R.; Taylor, Catherine L.; Rice, Mabel L.

    2012-01-01

    Purpose The primary objectives of this study were to determine the prevalence of late language emergence (LLE) and to investigate the predictive status of maternal, family, and child variables. Method This is a prospective cohort study of 1766 epidemiologically ascertained twenty-four-month singleton children. The framework was an ecological model of child development, encompassing a wide range of maternal, family, and child variables. Data were obtained using postal questionnaire. Item analyses of the 6-item Ages and Stages Questionnaire (ASQ) Communication Scale yielded a composite score encompassing comprehension as well as production items. One standard deviation below the mean yielded good separation of affected from unaffected children. Analyses of bivariate relationships with maternal, family, and child variables were carried out, followed by multivariate logistic regression to predict LLE group membership. Results 13.4% of the sample showed late language emergence via the ASQ criterion; 19.1% using a single item “combining words.” Risk for LLE at 24 months was not associated with particular strata of parental educational levels, socioeconomic resources, parental mental health, parenting practices or family functioning. Significant predictors included familial history of late language emergence, male gender and early neurobiological growth. Covariates included psychosocial indicators. Conclusion Results are congruent with models of language emergence and impairment that posit a strong role for neurobiological and genetic mechanisms of onset that operate across a wide variation in maternal and family characteristics. PMID:18055773

  8. [Molecular-genetic and epidemiologic examination of personnel subjected to occupational irradiation in the Russian Federal Nuclear Center (Sarov). Report 2. Genetic and non-genetic risk factors of morbidity].

    PubMed

    Korzeneva, I B; Malinina, T V; Afanas'ev, K I; Dubrova, Iu E; Skorodumova, E N; Samsonova, V F; Volkova, I V; Shishova, R T; Shcherbakova, I L

    2008-01-01

    Below is given a comparative evaluation of the genetic and the epidemiological examination of the cohort comprised by VNIIEF personnel subjected chronically to gamma-neutron ionizing radiation (74 persons), as well as nonirradiated cohort (74 persons). There are obtained data on the influence of the integral genotype structure on the health of an individual in case of occupational irradiation. The epidemiological analysis revealed statistically meaningful differences between the main and the control cohorts in the following five cases: acute respiratory diseases, diseases of upper respiratory tract, brain vessel malfunctions; illnesses connected with vision organs and cardio-vascular system and traumas. In such two cases as diseases of vision organs and cardio-vascular system the morbidity difference should be strictly attributed to the influence of the occupational factor. As a result of the genetic analysis it was shown that carriers of certain alleles of the loci ACP and Gc are credibly more susceptible to a number of diseases, when exposed to gamma-neutron irradiation. Besides, was proven that the occupational irradiation does not aggravate susceptibility to allergies and flew. PMID:19004325

  9. The National Heart, Lung, and Blood Institute retrovirus epidemiology donor studies (Retrovirus Epidemiology Donor Study and Retrovirus Epidemiology Donor Study-II): twenty years of research to advance blood product safety and availability.

    PubMed

    Kleinman, Steven; King, Melissa R; Busch, Michael P; Murphy, Edward L; Glynn, Simone A

    2012-10-01

    The Retrovirus Epidemiology Donor Study (REDS), conducted from 1989 to 2001, and the REDS-II, conducted from 2004 to 2012, were National Heart, Lung, and Blood Institute-funded, multicenter programs focused on improving blood safety and availability in the United States. The REDS-II also included international study sites in Brazil and China. The 3 major research domains of REDS/REDS-II have been infectious disease risk evaluation, blood donation availability, and blood donor characterization. Both programs have made significant contributions to transfusion medicine research methodology by the use of mathematical modeling, large-scale donor surveys, innovative methods of repository sample storage, and establishing an infrastructure that responded to potential emerging blood safety threats such as xenotropic murine leukemia virus-related virus. Blood safety studies have included protocols evaluating epidemiologic and/or laboratory aspects of human immunodeficiency virus, human T-lymphotropic virus 1/2, hepatitis C virus, hepatitis B virus, West Nile virus, cytomegalovirus, human herpesvirus 8, parvovirus B19, malaria, Creutzfeldt-Jakob disease, influenza, and Trypanosoma cruzi infections. Other analyses have characterized blood donor demographics, motivations to donate, factors influencing donor return, behavioral risk factors, donors' perception of the blood donation screening process, and aspects of donor deferral. In REDS-II, 2 large-scale blood donor protocols examined iron deficiency in donors and the prevalence of leukocyte antibodies. This review describes the major study results from over 150 peer-reviewed articles published by these 2 REDS programs. In 2011, a new 7-year program, the Recipient Epidemiology and Donor Evaluation Study-III, was launched. The Recipient Epidemiology and Donor Evaluation Study-III expands beyond donor-based research to include studies of blood transfusion recipients in the hospital setting and adds a third country, South Africa

  10. 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

  11. 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

  12. 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

  13. Epidemiology, pathology, and genetics of prostate cancer among African Americans compared with other ethnicities.

    PubMed

    Williams, Heinric; Powell, Isaac J

    2009-01-01

    Prostate cancer is the most common cancer affecting men in the Western world. In the United States, it is the second leading cause of cancer related deaths after lung and bronchus carcinoma. No definitive causes of prostate cancer (PCa) have been identified to date but, increasing age, a positive family history, and sub-Saharan African ancestry are strongly linked to its development. African American men (AAM) have the highest reported incidence rates in the United States and their mortality from the disease is markedly higher than that of European American men (EAM). Conversely, Asian American men and Pacific Islanders (API), American Indian and Alaskan Native (AI/AN) men, and Hispanic men all have lower incidence and mortality rates as compared with EAM. The reasons for these differences are unclear. However, it is clear that AAM have more advanced PCa when diagnosed. Several other reasons have been suggested and these include differences in treatments and health seeking behavior among the ethnic groups, cultural beliefs, environmental/lifestyle factors, dietary and genetic factors. In conclusion, there are multiple factors that impact prostate cancer outcome and that may be responsible for ethnic disparity. These factors are discussed in this chapter. PMID:19107447

  14. Hereditary ataxias and paraplegias in Cantabria, Spain. An epidemiological and clinical study.

    PubMed

    Polo, J M; Calleja, J; Combarros, O; Berciano, J

    1991-04-01

    A clinical, genetic and epidemiological study of hereditary ataxias and paraplegias was conducted within a defined area (Cantabria) in Northern Spain from 1974 to 1986. The series comprised 48 index cases and 65 affected relatives. On prevalence day, 103 patients were alive, giving a prevalence of 20.2 cases per 100,000. There were 24 patients (18 families) with Friedreich's ataxia (FA), 12 (6 families) with early onset cerebellar ataxia (EOCA) differing from FA, 6 (3 families) with dominantly transmitted late onset cerebellar ataxia (LOCA), 11 with 'idiopathic' LOCA, 49 (9 families) with 'pure' hereditary spastic paraplegia (HSP), and 1 patient with congenital cerebellar ataxia. The prevalence found here is comparable with the highest figures described in previous surveys. This may in part be due to the great number of secondary cases in our series. A high frequency of parental consanguinity occurred in FA patients, 'pseudodominant' inheritance being observed in 1 family. The clinical features were those of classical FA except for later onset and slower course in 1 family, and retained tendon reflexes in the lower limbs in 2 cases. Such data indicate the need for modification of the essential criteria for the disease. EOCA included 4 patients with normoreflexic ataxia and 1 patient with ataxia and luteinizing hormone-releasing hormone deficiency. In addition, there were 7 patients from 2 unrelated families with a homogeneous syndrome characterized by autosomal recessive inheritance, cerebellar ataxia, retinitis pigmentosa and sensory neuropathy. This syndrome is therefore a well defined nosological entity to be added to the list of autosomal recessive mendelian phenotypes. The clinical picture of patients with LOCA was either a 'pure' cerebellar or a 'cerebellar-plus' syndrome. Genetic subgroups of 'pure' HSP were autosomal dominant type I in 5 families and type II in 2, and autosomal recessive in 2 families. PMID:2043954

  15. 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

  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. 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

  18. Molecular epidemiological analysis of Mycoplasma bovis isolates from the Pennsylvania Animal Diagnostic Laboratory showing genetic diversity.

    PubMed

    Soehnlen, M K; Kariyawasam, S; Lumadue, J A; Pierre, T A; Wolfgang, D R; Jayarao, B M

    2011-04-01

    We have examined the genetic variability of Mycoplasma bovis strains submitted to the Pennsylvania Animal Diagnostics Laboratory, University Park (PA-ADL), between December 2007 and December 2008. Of 4,868 total samples submitted for Mycoplasma testing, 302 were determined to be culture positive. Mycoplasma bovis (63.6%), Mycoplasma californicum (7.3%), Mycoplasma bovirhinis (2.7%), Mycoplasma bovigenitalium (0.7%), Mycoplasma alkalescens (4.9%), Mycoplasma putrefaciens (0.3%), and Mycoplasma dispar (1.3%) and unidentified Mycoplasma sp. (19.2%) were identified using PCR. Mycoplasma bovis represented the largest portion of the positive samples submitted. Each of the 192 M. bovis isolates was examined for variations in the BglII and MfeI restriction sites of the DNA using amplified fragment length polymorphism fingerprinting and subsequently compared with the M. bovis type strain PG45 (ATCC 25523). Similarity between strains was calculated using the Dice similarity coefficient, which ranged from approximately 0.7 to 1.0. When clustering the isolates at greater than 95% similarity, it was determined that 11 distinct clusters were present. The results are consistent with the existence of at least 2 clonally distinct groups. No clear geographical, month of isolation, or source origination relationship was identified, indicating that a currently unclassified characteristic is responsible for the strain heterogeneity. These data indicate strong heterogeneity of M. bovis isolates submitted to PA-ADL. Additionally, multiple sites throughout Pennsylvania had isolates of separate clonal lineages present concomitantly, indicating the ability of multiple overlapping outbreaks to occur at a single location. Mycoplasma bovis represents the largest portion of Mycoplasma species isolated from PA-ADL samples. We propose that amplified fragment length polymorphism may serve as a valuable tool for molecular characterization of M. bovis strains from the United States. PMID:21426978

  19. The Brazilian Football Association (CBF) model for epidemiological studies on professional soccer player injuries

    PubMed Central

    Arliani, Gustavo Gonçalves; Belangero, Paulo Santoro; Runco, Jose Luiz; Cohen, Moisés

    2011-01-01

    OBJECTIVE: This study aims to establish a national methodological model for epidemiological studies on professional soccer player injuries and to describe the numerous relevant studies previously published on this topic. INTRODUCTION: The risk of injury in professional soccer is high. However, previous studies of injury risk in Brazil and other countries have been characterized by large variations in study design and data collection methods as well as definitions of injury, standardized diagnostic criteria, and recovery times. METHODS: A system developed by the Union of European Football for epidemiological studies on professional soccer players is being used as a starting point to create a methodological model for the Brazilian Football Association. To describe the existing studies on professional soccer player injuries, we developed a search strategy to identify relevant epidemiological studies. We included the Latin American and Caribbean Center on Health Sciences and Medline databases in our study. RESULTS: We considered 60 studies from Medline and 16 studies from the Latin American and Caribbean Center on Health Sciences in the final analysis. Twelve studies were selected for final inclusion in this review: seven from the Latin American and Caribbean Center on Health Sciences and five from Medline. We identified a lack of uniformity in the study design, data collection methods, injury definitions, standardized diagnostic criteria, and the definition of recovery time. Based on the information contained within these articles, we developed a model for epidemiological studies for the Brazilian Football Association. CONCLUSIONS: There is no uniform model for epidemiological studies of professional soccer injuries. Here, we propose a novel model to be applied for epidemiological studies of professional soccer player injuries in Brazil and throughout the world. PMID:22012041

  20. Using Geographic Information Systems for Exposure Assessment in Environmental Epidemiology Studies

    PubMed Central

    Nuckols, John R.; Ward, Mary H.; Jarup, Lars

    2004-01-01

    Geographic information systems (GIS) are being used with increasing frequency in environmental epidemiology studies. Reported applications include locating the study population by geocoding addresses (assigning mapping coordinates), using proximity analysis of contaminant source as a surrogate for exposure, and integrating environmental monitoring data into the analysis of the health outcomes. Although most of these studies have been ecologic in design, some have used GIS in estimating environmental levels of a contaminant at the individual level and to design exposure metrics for use in epidemiologic studies. In this article we discuss fundamentals of three scientific disciplines instrumental to using GIS in exposure assessment for epidemiologic studies: geospatial science, environmental science, and epidemiology. We also explore how a GIS can be used to accomplish several steps in the exposure assessment process. These steps include defining the study population, identifying source and potential routes of exposure, estimating environmental levels of target contaminants, and estimating personal exposures. We present and discuss examples for the first three steps. We discuss potential use of GIS and global positioning systems (GPS) in the last step. On the basis of our findings, we conclude that the use of GIS in exposure assessment for environmental epidemiology studies is not only feasible but can enhance the understanding of the association between contaminants in our environment and disease. PMID:15198921

  1. Extrapolation from occupational studies: a substitute for environmental epidemiology.

    PubMed Central

    Enterline, P E

    1981-01-01

    Extrapolation from occupational data to general environmental exposures gives some interesting results, and these results might be useful in our decision-making process. These results could never be observed by environmental epidemiology and this method probably represents the only way of quantifying the health effects of low-exposure levels. Three linear models for extrapolating to low levels are presented--one from Canadian data, one from American data and one from British data. One or more of these is applied to two recently publicized asbestos exposures; exposures resulting from asbestos heat shields in hair dryers and exposures in public school buildings. Predictions are derived as to the effects of asbestos exposures on cancer mortality. A comparison is made between predictions made on the basis of a linear and nonlinear model. PMID:7333259

  2. 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

  3. 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

  4. Brief Report: Negative Controls to Detect Selection Bias and Measurement Bias in Epidemiologic Studies.

    PubMed

    Arnold, Benjamin F; Ercumen, Ayse; Benjamin-Chung, Jade; Colford, John M

    2016-09-01

    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

  5. 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

  6. Molecular epidemiology of PRRSV in South China from 2007 to 2011 based on the genetic analysis of ORF5.

    PubMed

    Xie, Jiexiong; Zhu, Wanjun; Chen, Ye; Wei, Chunya; Zhou, Pei; Zhang, Minze; Huang, Zhen; Sun, Long; Su, Shuo; Zhang, Guihong

    2013-10-01

    Porcine reproductive and respiratory syndrome virus (PRRSV) has proven to be highly genetically variable; however, comprehensive information regarding the virus's genetic diversity in South China is limited. In this study, a total of 3199 clinical samples were collected from 267 pig farms suspected of PRRSV infection between 2007 and 2011. The ORF5 genes of 51 PRRSV-positive samples were sequenced and analyzed. The 51 study strains were divided into three primary subgenotypes. Fourty-five of the strains belonged to subgenotype I and were closely related to the highly pathogenic PRRSV (HP-PRRSV) strains. The subgenotype I strains were generally clustered into genetically similar groups by year. Only one of the strains belonged to subgenotype II, clustering with the classical North American type, VR2332. Five of the strains were grouped into subgenotype III, which occupied a separate branch and was closely related to the recently isolated novel field strains, QYYZ and GM2. The 5 subgenotype III strains shared an amino acid identity with the remaining 46 study strains ranging from 79.6%-83.6%. Amino acid analysis showed extensive mutations in subgenotype III; the diverse genetic mutations of these novel strains are of great concern. PMID:23770054

  7. The Influences of Genetic and Environmental Factors on Methylome-wide Association Studies for Human Diseases

    PubMed Central

    Sun, Yan V.

    2014-01-01

    DNA methylation (DNAm) is an essential epigenetic mechanism for normal development, and its variation may be associated with diseases. High-throughput technology allows robust measurement of DNA methylome in population studies. Methylome-wide association studies (MWAS) scan DNA methylome to detect new epigenetic loci affecting disease susceptibility. MWAS is an emerging approach to unraveling the mechanism linking genetics, environment, and human diseases. Here I review the recent studies of genetic determinants and environmental modifiers of DNAm, and the concept for partitioning genetic and environmental contribution to DNAm. These studies establish the correlation maps between genome and methylome, and enable the interpretation of epigenetic association with disease traits. Recent findings suggested that MWAS was a promising genomic method to identify epigenetic predictors accounting for unexplained disease risk. However, new study designs, analytical methods and shared resources need to be implemented to address the limitations and challenges in future epigenomic epidemiologic studies. PMID:25422794

  8. 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. PMID:21254216

  9. AN EPIDEMIOLOGICAL FEASIBILITY STUDY AND A BIOMARKER STUDY FOR ASSESSING HEALTH EFFECTS OF ARSENIC IN INNER MONGOLIA, CHINA

    EPA Science Inventory

    Epidemiology Studies: This work will be accomplished through: (a) building data bases; evaluating existing data, including published (mostly in Chinese) and unpublished data on arsenic exposure and health effects in Inner Mongolia and publishing this summary analysis in English l...

  10. 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. PMID:27530838

  11. Translational Epidemiology in Psychiatry

    PubMed Central

    Weissman, Myrna M.; Brown, Alan S.; Talati, Ardesheer

    2012-01-01

    Translational research generally refers to the application of knowledge generated by advances in basic sciences research translated into new approaches for diagnosis, prevention, and treatment of disease. This direction is called bench-to-bedside. Psychiatry has similarly emphasized the basic sciences as the starting point of translational research. This article introduces the term translational epidemiology for psychiatry research as a bidirectional concept in which the knowledge generated from the bedside or the population can also be translated to the benches of laboratory science. Epidemiologic studies are primarily observational but can generate representative samples, novel designs, and hypotheses that can be translated into more tractable experimental approaches in the clinical and basic sciences. This bedside-to-bench concept has not been explicated in psychiatry, although there are an increasing number of examples in the research literature. This article describes selected epidemiologic designs, providing examples and opportunities for translational research from community surveys and prospective, birth cohort, and family-based designs. Rapid developments in informatics, emphases on large sample collection for genetic and biomarker studies, and interest in personalized medicine—which requires information on relative and absolute risk factors—make this topic timely. The approach described has implications for providing fresh metaphors to communicate complex issues in interdisciplinary collaborations and for training in epidemiology and other sciences in psychiatry. PMID:21646577

  12. Descriptive Epidemiology of Clubfoot in Peru: A Clinic-Based Study

    PubMed Central

    Palma, Melissa; Cook, Thomas; Segura, Julio; Pecho, Augustin; Morcuende, Jose A

    2013-01-01

    congenital clubfoot is the most common birth defect of the musculoskeletal system and affects 1 in every 1000 live births each year.1 Although there have been numerous studies of investigation, the etiology and pathogenesis of clubfoot remains unknown. To date, no epidemiological studies have been conducted in Peru to assess possible genetic and environmental risk factors associated with this deformity. The purpose of this study was to evaluate specific environmental and socioeconomic factors that may increase the risk of clubfoot. A descriptive clinic-based study was conducted using structured questionnaires given to biological mothers of clinically confirmed clubfoot patients (n=72) and biological mothers of children between ages 0-18 with no first or second degree family history of clubfoot as controls (n=103). Phenotypic data from clubfoot subjects were also collected. We found that males were twice as likely to have clubfoot as females, and half of all clubfoot patients had bilateral clubfoot. There was no significant difference in the rate of left vs. right clubfoot. Infant birth in the winter months correlated with an increased risk of clubfoot (p=0.01476). Maternal characteristics found to be significantly associated with increased risk of clubfoot were young maternal age at conception (p=0.04369) and low maternal education (p=0.003245). Young paternal age also had a correlation with increased risk of clubfoot in the child (p=0.0371). Both paternal smoking (p=0.00001) and the presence of any household smoking (p=0.00003) were strongly associated with an increased risk of clubfoot. PMID:24027478

  13. 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

  14. 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…

  15. Perspectives on population-based epidemiological studies of olfactory and taste impairment

    PubMed Central

    Hoffman, Howard J.; Cruickshanks, Karen J; Davis, Barry

    2009-01-01

    Epidemiological studies of the senses of olfaction (smell) and gustation (taste) are needed since impairments in these senses have important implications for health. Only a few attempts have been made to measure the prevalence of olfactory and gustatory or taste dysfunction and many methodological challenges remain to be addressed. These challenges differ from those faced in studies based in the clinic or research laboratory. Epidemiological studies of smell and taste represent translational research, since they can be used to understand how findings from laboratory or clinical studies apply to the general population. This paper briefly reviews existing methods for “how” to measure smell and taste dysfunction and then illustrates findings based on prior epidemiological studies to indicate “why” we wish to measure smell and taste functioning in population-based samples. Self report information collected on smell and taste loss in a national sample, the 1994–1995 Disability Sample (Phase I screening) of the National Health Interview Survey (NHIS-D), is contrasted with results provided by an exam-based measure of olfactory impairment in an epidemiological study conducted in Beaver Dam, WI. The comparison of self report and exam-based measures of smell or taste loss leads to the question of how to best define smell or taste impairment in population samples, since unlike other sensory domains (namely, vision and hearing), there are no internationally accepted standards of impairment for the chemosenses. In addition to highlighting existing epidemiological studies, the current development of an NIH Toolbox of brief exam measures is described. Through this symposium, we hope to advance the nascent field of olfactory and taste epidemiology. PMID:19686188

  16. The Ischemic Stroke Genetics Study (ISGS) Protocol

    PubMed Central

    Meschia, James F; Brott, Thomas G; Brown, Robert D; Crook, Richard JP; Frankel, Michael; Hardy, John; Merino, José G; Rich, Stephen S; Silliman, Scott; Worrall, Bradford Burke

    2003-01-01

    Background The molecular basis for the genetic risk of ischemic stroke is likely to be multigenic and influenced by environmental factors. Several small case-control studies have suggested associations between ischemic stroke and polymorphisms of genes that code for coagulation cascade proteins and platelet receptors. Our aim is to investigate potential associations between hemostatic gene polymorphisms and ischemic stroke, with particular emphasis on detailed characterization of the phenotype. Methods/Design The Ischemic Stroke Genetic Study is a prospective, multicenter genetic association study in adults with recent first-ever ischemic stroke confirmed with computed tomography or magnetic resonance imaging. Patients are evaluated at academic medical centers in the United States and compared with sex- and age-matched controls. Stroke subtypes are determined by central blinded adjudication using standardized, validated mechanistic and syndromic classification systems. The panel of genes to be tested for polymorphisms includes β-fibrinogen and platelet glycoprotein Ia, Iba, and IIb/IIIa. Immortalized cell lines are created to allow for time- and cost-efficient testing of additional candidate genes in the future. Discussion The study is designed to minimize survival bias and to allow for exploring associations between specific polymorphisms and individual subtypes of ischemic stroke. The data set will also permit the study of genetic determinants of stroke outcome. Having cell lines will permit testing of future candidate risk factor genes. PMID:12848902

  17. Usefulness of comprehensive feasibility studies in environmental epidemiology investigations: a case study in Minnesota.

    PubMed Central

    Bender, A P; Williams, A N; Sprafka, J M; Mandel, J S; Straub, C P

    1988-01-01

    Episodes of public water supply contamination with industrial or agricultural chemicals frequently give rise to public concerns about adverse health effects. These concerns may precipitate epidemiologic or clinical investigations requiring large expenditures of state and federal resources regardless of whether such investigations are justified by scientific criteria. An alternative is a comprehensive feasibility study, utilizing all available information to determine whether large-scale studies are warranted or feasible. At a relatively modest cost, a feasibility study allows health officials to identify information needs and deficiencies, outline potential study options and costs, clearly establish the rationale for a proposed study or, conversely, prevent unwarranted expenditures of public resources. Furthermore, a feasibility study may in itself resolve many community and scientific concerns. This article provides a case study of the usefulness of a formal feasibility study in a situation involving an elevated cancer rate and contaminated municipal water supply wells surrounding a federal superfund site. PMID:3341499

  18. Antenatal genetic studies in twin pregnancies.

    PubMed

    Redwine, F O; Cruikshank, D P; Brown, J

    1984-01-01

    The diagnosis of multiple gestation at the time of genetic amniocentesis is a routine occurrence. In a combined series of 2765 patients referred for antenatal genetic studies from the Medical College of Virginia and the University of Iowa, 34 twin pregnancies were encountered (1.2%). Twenty-six of the patients with twins were referred for advanced maternal age. The other indications were previous neural tube defects (1), previous trisomy 21 (2), known carriers of Tay Sachs disease (2), previous Turner's syndrome (1), family history of trisomy 21 (1), and one pregnancy was referred because of an abnormal ultrasound. Amniocentesis procedures, outcome of the twin pregnancies, and genetic counseling issues, are discussed. PMID:6741416

  19. 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

  20. 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

  1. Metastatic renal cell carcinoma: update on epidemiology, genetics, and therapeutic modalities

    PubMed Central

    Graves, Angela; Hessamodini, Hannah; Wong, Germaine; Lim, Wai H

    2013-01-01

    The treatment of advanced renal cell carcinoma (RCC) remains a major therapeutic challenge for clinicians. Despite advances in the understanding of the immunobiology of RCC and the availability of several novel targeted agents, there has been little improvement in the survival of patients with metastatic RCC. This review will focus on the recent understanding of risk factors and treatment options and outcomes of metastatic RCC, in particular, targeted therapeutic agents that inhibit vascular endothelial growth factor and mammalian target of rapamycin pathways. Prospective studies are required to determine whether sequential targeted therapy will further improve progression-free survival in RCC. Ongoing research to develop novel agents with better tolerability and enhanced efficacy in the treatment of metastatic RCC is required.

  2. Analysis of Factors Influencing Telephone Call Response Rate in an Epidemiological Study

    PubMed Central

    Matías-Guiu, Jorge; Serrano-Castro, Pedro Jesús; Mauri-Llerda, José Ángel; Hernández-Ramos, Francisco José; Sánchez-Alvarez, Juan Carlos; Sanz, Marisa

    2014-01-01

    Descriptive epidemiology research involves collecting data from large numbers of subjects. Obtaining these data requires approaches designed to achieve maximum participation or response rates among respondents possessing the desired information. We analyze participation and response rates in a population-based epidemiological study though a telephone survey and identify factors implicated in consenting to participate. Rates found exceeded those reported in the literature and they were higher for afternoon calls than for morning calls. Women and subjects older than 40 years were the most likely to answer the telephone. The study identified geographical differences, with higher RRs in districts in southern Spain that are not considered urbanized. This information may be helpful for designing more efficient community epidemiology projects. PMID:25401127

  3. 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

  4. 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

  5. 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

  6. 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

  7. 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

  8. Presymptomatic studies in genetic frontotemporal dementia.

    PubMed

    Rohrer, J D; Warren, J D; Fox, N C; Rossor, M N

    2013-10-01

    Approximately 20% of patients with the neurodegenerative disorder frontotemporal dementia (FTD) have an autosomal dominant pattern of inheritance. Genetic FTD is caused by mutations in three genes in most cases (progranulin, microtubule-associated protein tau and chromosome 9 open reading frame 72) although a number of other genes are rare causes. Studies of other neurodegenerative diseases have shown imaging and biomarker evidence of disease onset many years prior to the development of symptoms. Similar studies in genetic FTD are now revealing evidence of a series of presymptomatic changes, initially in plasma biomarkers followed by MR imaging abnormalities of functional and structural connectivity and then grey matter atrophy. Lastly, neuropsychometric tests become abnormal in proximity to the onset of symptoms. Such studies have been relatively small until now but research centres with an expertise in genetic FTD are now forming consortia such as the Genetic Frontotemporal Dementia Initiative (GenFI) to create larger cohorts that can form the basis of future clinical trials. PMID:24012408

  9. Clinico-epidemiological study of donovanosis in Durban, South Africa.

    PubMed Central

    O'Farrell, N

    1993-01-01

    OBJECTIVE: To describe the epidemiological and clinical features of donovanosis and their relevance to the possible coincident risk of HIV-1 transmission in patients attending an STD clinic. DESIGN: Assessment of patients with donovanosis diagnosed by the detection of Donovan bodies on tissue smears stained by the RapiDiff technique. SETTING: City Health STD Clinic, King Edward VIII Hospital, Durban, South Africa. PARTICIPANTS: One hundred and seventy one patients with donovanosis. RESULTS: Donovan bodies were detected in 171 (130 men, 41 women). Ulcers were present for longer than 28 days in 72 (55.4%) men and 19 (46.3%) women. Ninety five (55.6%) came from rural areas. Lesions were ulcero-granulomatous in 162, hypertrophic in eight and necrotic in one. Anal lesions were detected in one woman. Only one of 21 regular sexual partners examined was infected with donovanosis. Complete healing was observed in 41 (24%) who attended for follow up. Extensive lesions were sometimes observed in pregnant women. Serological tests for syphilis were positive in 40 (23.4%). HIV-1 antibodies were detected in 4/48 men and 0/15 women who underwent HIV testing. Donovanosis ulcers in three HIV-1 seropositive men were cured by standard antibiotic therapy. CONCLUSIONS: Delay in presentation, extensive areas of genital ulceration and lack of co-existent infection with donovanosis among sexual partners were notable features. Primary health care facilities in rural areas do not appear to be providing an adequate service for patients with donovanosis. HIV control programmes should consider specific measures aimed at eradicating donovanosis in areas where the condition is prevalent. PMID:8509089

  10. Ribotyping of Pseudomonas aeruginosa: discriminatory power and usefulness as a tool for epidemiological studies.

    PubMed Central

    Blanc, D S; Siegrist, H H; Sahli, R; Francioli, P

    1993-01-01

    Restriction fragment length polymorphism of ribosomal DNA regions (ribotyping) of Pseudomonas aeruginosa was evaluated as a tool for epidemiological purposes. Fifty-five epidemiologically unrelated isolates from three geographic areas of Switzerland and 11 isolates obtained during an outbreak of P. aeruginosa infections in a burn unit were typed by this method. Typeability and reproducibility of the method reached 100%. With four selected restriction enzymes (BamHI, ClaI, EcoRI, and PstI), the 55 unrelated isolates could be classified into 33 ribotypes. To assess the value of this method for the interpretation of epidemiological data, we calculated an index of discrimination (ID) which takes into consideration both the number of types defined by the typing method and their relative frequencies. Our ribotyping system obtained a high ID of 0.958 with only four restriction enzymes, comparing well with other different typing schemes for which ID values could be calculated from published data. All clinical isolates of the outbreak belonged to the same ribotype, whereas environmental isolates, initially thought to be the source of the epidemic, belonged to a different ribotype. Thus, the typeability, reproducibility, and discriminatory power of our method as well as its value established in an epidemiological investigation were found to be appropriate for further epidemiological studies of P. aeruginosa. Images PMID:8093252

  11. The Center for Epidemiologic Studies Depression Scale with a Young Adolescent Population: A Confirmatory Factor Analysis

    ERIC Educational Resources Information Center

    Phillips, Glenn A.; Shadish, William R.; Murray, David M.; Kubik, Martha; Lytle, Leslie A.; Birnbaum, Amanda S.

    2006-01-01

    The Center for Epidemiological Studies Depression scale (CES-D) was developed to assess the population prevalence of depression. The CES-D was developed and normed on an adult population. Since the CES-D's publication, various studies have both used and psychometrically assessed the scale for older adolescent populations. However, we found no…

  12. Late Language Emergence at 24 Months: An Epidemiological Study of Prevalence, Predictors, and Covariates

    ERIC Educational Resources Information Center

    Zubrick, Stephen R.; Taylor, Catherine L.; Rice, Mabel L.; Slegers, David W.

    2007-01-01

    Purpose: The primary objectives of this study were to determine the prevalence of late language emergence (LLE) and to investigate the predictive status of maternal, family, and child variables. Method: This is a prospective cohort study of 1,766 epidemiologically ascertained 24-month-old singleton children. The framework was an ecological model…

  13. 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 ...

  14. 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…

  15. 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

  16. A pilot study: research poster presentations as an educational tool for undergraduate epidemiology students

    PubMed Central

    Deonandan, Raywat; Gomes, James; Lavigne, Eric; Dinh, Thy; Blanchard, Robert

    2013-01-01

    Students in a fourth year epidemiology course were surveyed after participating in a formal Science Research Day in which they presented original research, in poster form, to be judged by scientists from the community. Of 276 participating students, 80 (29%) responded to the study survey. As a result, 19% of respondents were more likely to pursue a career in science, and 27.5% were more likely to pursue a career in epidemiology. Only one respondent reported being less likely to pursue a science career, while seven were less likely to pursue epidemiology. A majority of respondents felt that the poster experience was on par with, or superior to, a comparable research paper, in terms of both educational appeal and enjoyment. Mandatory, formal poster presentations are an innovative format for teaching advanced health sciences, and may more accurately reflect the realities of a science career than do more traditional educational formats. PMID:24101888

  17. Pattern analysis in the study of infantile diarrhoea and other epidemiological problems*

    PubMed Central

    Mansourian, B. G.; Sayers, B. McA

    1979-01-01

    The patterns imposed on records of epidemiological variables by spatial, temporal, and other factors demand a special approach for their identification, characterization, and interpretation. Over the last 10 years, a methodology based on pattern analysis has been developed and put to the test in elucidating selected epidemiological problems. The aim of this approach is to link the pattern or its detailed features to factors likely to be important in understanding the origins of the disease and the mechanisms underlying its occurrence; such knowledge may in turn suggest methods that can be used to control the disease. Pattern analysis provides a battery of techniques that can greatly enhance the cost-effectiveness of epidemiological investigations. To exemplify these techniques, the applications of pattern analysis in the study of the infantile diarrhoeal complex and in elucidating the epidemic spread of wildlife rabies are described. Some other examples are mentioned briefly and comments are made on the more important techniques available. PMID:317018

  18. 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. PMID:26096964

  19. Epidemiology and genetic characterization of BVDV, BHV-1, BHV-4, BHV-5 and Brucella spp. infections in cattle in Turkey

    PubMed Central

    ASLAN, Muhammet Eren; AZKUR, Ahmet Kursat; GAZYAGCI, Serkal

    2015-01-01

    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. PMID:26096964

  20. Spanish Multicenter Study of the Epidemiology and Mechanisms of Amoxicillin-Clavulanate Resistance in Escherichia coli

    PubMed Central

    Ortega, Adriana; 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, Álvaro; Rivera, Alba; Rodríguez-Baño, Jesús; Weber, Irene; Aracil, Belén; Campos, José

    2012-01-01

    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

  1. 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

  2. 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

  3. Stability and Reproducibility of the Measurement of Plasma Nitrate in Large Epidemiologic Studies.

    PubMed

    Wang, Yushan; Townsend, Mary K; Eliassen, A Heather; Wu, Tianying

    2013-04-01

    Inorganic nitrate has emerged as a therapeutic agent for cardiovascular disease; however, nitrate can also metabolize to carcinogenic nitrosamines under pathologic conditions. Few large epidemiologic studies have examined circulating levels of nitrate in relation to cardiovascular disease and cancer. Data on the validity of nitrate measurement in blood samples collected in typical epidemiologic settings are needed before nitrate can be evaluated as an exposure in large epidemiologic studies. We measured plasma levels of nitrate in three pilot studies to evaluate its laboratory variability, stability with delayed processing, and reproducibility over time among women from the Nurses' Health Study and healthy female volunteers. Laboratory variability of nitrate levels was fairly low, with a coefficient variation (CV) of 7%. Plasma nitrate levels in samples stored as whole blood on ice for up to 48 hrs before processing were very stable; the overall intra-class correlation (ICC) from 0 to 48 hours was 0.89 (95%CI, 0.70-0.97). The within-person reproducibility over a one-year period was modest, with an ICC of 0.49 (95% CI, 0.33- 0.94). Our results indicate that measurement of nitrate in plasma is reliable and stable in blood samples with delayed processing up to 48 hours. Within-person reproducibility was modest but data from this study can be used for measurement error correction in subsequent analyses. The measurement of nitrate cannot be widely used in epidemiologic research without the documentation of its stability and reproducibility. PMID:24244804

  4. 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

  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. 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

  7. 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"...

  8. 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...

  9. APPLYING DATA ASSIMILATION AND ADJOINT SENSITIVITY TO EPIDEMIOLOGICAL AND POLICY STUDIES OF AIRBORNE PARTICULATE MATTER

    EPA Science Inventory

    Source-resolved fine particulate matter (PM) concentrations are needed at high spatial and temporal resolutions for epidemiological studies aimed at identifying more- and less-harmful types of PM. Building on recent advances in air quality modeling, data assimilation, and s...

  10. PROSPECTIVE EPIDEMIOLOGICAL STUDY OF HEALTH RISKS ASSOCIATED WITH WASTEWATER UTILIZATION IN AGRICULTURE (JOURNAL VERSION)

    EPA Science Inventory

    A prospective epidemiological morbidity and serology study was carried out in Israel in 1980/82 on the association between enteric disease incidence and wastewater utilization in 29 kibbutzim. Analysis of morbidity data indicate that no significant excess of enteric disease episo...

  11. 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...

  12. 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…

  13. 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…

  14. 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…

  15. "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...

  16. 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

  17. 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

  18. 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

  19. Implementing a Graduate Certificate Program in Cardiovascular Epidemiology: The Jackson Heart Study.

    PubMed

    Campbell Jenkins, Brenda W; Addison, Clifton; Wilson, Gregory; Young, Lavon; Fields, Regina; Woodberry, Clevette; Payton, Marinelle

    2016-01-01

    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

  20. [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

  1. 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

  2. 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

  3. 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

  4. Epidemiology and Clinical Research Design, Part 1: Study Types

    PubMed Central

    Manja, Veena; Lakshminrusimha, Satyan

    2015-01-01

    Selecting the best available preventive and therapeutic measures to avoid disability and death is an important goal for all health care practitioners. To achieve this goal, we need to perform studies that determine the value of these measures. In this article, we discuss the possible study designs that can be used for evaluating new approaches to prevention and treatment. The gold standard study design is a randomized, controlled, double-blind trial. In many instances, a randomized controlled trial may not be ethically or practically feasible. Other study types, such as case series, case-control studies, cohort studies, cross-sectional studies, crossover designs, and open-label studies, may be required to hypothesize and evaluate the link between an exposure or predictor variable and an outcome variable. Various study types pertaining to neonatal-perinatal medicine are reviewed in this article. PMID:25848346

  5. [Eco-epidemiology: towards epidemiology of complexity].

    PubMed

    Bizouarn, Philippe

    2016-05-01

    In order to solve public health problems posed by the epidemiology of risk factors centered on the individual and neglecting the causal processes linking the risk factors with the health outcomes, Mervyn Susser proposed a multilevel epidemiology called eco-epidemiology, addressing the interdependence of individuals and their connection with molecular, individual, societal, environmental levels of organization participating in the causal disease processes. The aim of this epidemiology is to integrate more than a level of organization in design, analysis and interpretation of health problems. After presenting the main criticisms of risk-factor epidemiology focused on the individual, we will try to show how eco-epidemiology and its development could help to understand the need for a broader and integrative epidemiology, in which studies designed to identify risk factors would be balanced by studies designed to answer other questions equally vital to public health. PMID:27225924

  6. 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

  7. 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.

  8. Epidemiology of Giardia duodenalis infection in ruminant livestock and children in the Ismailia province of Egypt: insights by genetic characterization

    PubMed Central

    2014-01-01

    Background Giardia duodenalis is a common flagellated protozoan parasite that infects the small intestine of a wide range of vertebrate hosts. This study aimed to determine whether tracing of G. duodenalis isolates by current genetic typing tools is possible using an exemplary set of samples from infected cattle, buffalo and children from the Ismailia province, Egypt. Method A total of 804 fecal samples from ruminant animals was collected from 191 herds and 165 samples from diarrheal children below the age of 10 years. Parasites were detected in these samples using the copro-antigen RIDA®QUICK test and by real-time PCR. Samples were then genetically characterized based on the triosephosphate isomerase, glutamate dehydrogenase and β-giardin genes. Results The prevalence of G. duodenalis was 53% in ruminants and 21% in symptomatic children and infection was not positively correlated with diarrheal symptoms. Sequence typing analysis confirmed predominance of B-type sequences (>67%) in humans and E-type sequences (>81%) in ruminants over A-type sequences. For 39 samples the complete sequence information of the three marker gene fragments could be derived. Integration of the concatenated sequence information of the three marker gene fragments with the spatial data of the respective sample revealed that identical or near identical (only up to 1 out of 1358 bp different) concatenated sequencing types were spatially related in 4 out of 5 cases. Conclusion The risk of zoonotic infection emanating from ruminants even in high prevalence areas is negligible. Genetic characterization indicated a predominant anthropogenic cycle of infection within the pediatric population studied. Integration of sequence typing data with information on geographic origins of samples allows parasite sub-population tracing using current typing tools. PMID:25015671

  9. 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

  10. Insights into the epidemiology and genetic make-up of Oesophagostomum bifurcum from human and non-human primates using molecular tools.

    PubMed

    Gasser, R B; de Gruijter, J M; Polderman, A M

    2006-04-01

    The nodule worm Oesophagostomum bifurcum (Nematoda: Strongylida) is a parasite of major human health importance predominantly in northern Togo and Ghana. Currently, it is estimated that 0.25 million people are infected with this nematode, and at least 1 million people are at risk of infection. Infection with this parasite causes significant disease as a consequence of encysted larvae in the wall of the large intestine. In spite of the health problems caused by O. bifurcum, there have been significant gaps in the knowledge of the biology, transmission and population genetics of the parasite. This review provides an account of some recent insights into the epidemiology and genetics of the parasite from human and non-human primate hosts in specific regions of Africa using molecular tools. Recent research findings are discussed mainly in relation to non-human primates being reservoirs of infection, and the consequences for the prevention and control of oesophagostomiasis in humans are briefly discussed. PMID:16332292

  11. 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.

  12. Occupational epidemiology in agriculture: a case study in the southern African context.

    PubMed

    London, L

    1998-01-01

    Some challenges facing occupational epidemiology in developing countries are outlined in this case study of agriculture drawing on Southern African research. These include the characterization of exposures in resource- and data-poor environments typical of developing countries, the assessment of outcomes where cross-cultural and socio-environmental confounders may be substantial obstacles, and the impact of environmental exposures on workplace health. Traditional assignment of low priority to the chronic effects of low-dose exposures relative to acute morbidity in developing countries must be critically examined, as must the gender bias of much occupational epidemiology in agriculture. Advocacy issues involving child labor and the ethics of research among vulnerable groups deserve rigorous attention. It is argued that, if occupational epidemiology is to have meaningful impact on the health of the most marginalized groups of workers in developing countries, it must redefine itself in terms of a public health approach. The boundaries of epidemiologic inquiry need to be broad, and amenable to interfacing with policy research, using qualitative methods and participatory approaches. More so than in order industrial settings, epidemiologists must move from research to practice, seeking to take action where interventions are needed, and to evaluate such actions. PMID:9876634

  13. Latino adults' access to mental health care: a review of epidemiological studies.

    PubMed

    Cabassa, Leopoldo J; Zayas, Luis H; Hansen, Marissa C

    2006-05-01

    Since the early 1980s, epidemiological studies using state-of-the-art methodologies have documented the unmet mental health needs of Latinos adults in the U.S. and Puerto Rico. This paper reviews 16 articles based on seven epidemiological studies, examines studies methodologies, and summarizes findings about how Latino adults access mental health services. Studies consistently report that, compared to non-Latino Whites, Latinos underutilize mental health services, are less likely to receive guideline congruent care, and rely more often on primary care for services. Structural, economic, psychiatric, and cultural factors influence Latinos' service access. In spite of the valuable information these studies provide, methodological limitations (e.g., reliance on cross-sectional designs, scarcity of mixed Latino group samples) constrict knowledge about Latinos access to mental health services. Areas for future research and development needed to improve Latinos' access and quality of mental health care are discussed. PMID:16598658

  14. 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

  15. 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...

  16. Assessing the connection between organophosphate pesticide poisoning and mental health: A comparison of neuropsychological symptoms from clinical observations, animal models and epidemiological studies.

    PubMed

    Stallones, Lorann; Beseler, Cheryl L

    2016-01-01

    Psychiatry and psychology are beginning to recognize the importance of lead, mercury and heavy metals as causal partners in the development of mental disorders. Further, mental health researchers and clinicians are embracing the idea that the combined effects of genetics and environmental exposures can result in perturbations in brain neurochemistry leading to psychiatric disorders. The purpose of this review is to examine the biological foundations for the epidemiological observations previously identified by reviewing the toxicology literature and relating it to epidemiological studies addressing the role of poisoning with organophosphate pesticides (OPs) in neurobehavioral and neuropsychological disorders. The goal of this review is to raise awareness in the mental health community about the possibility that affective disorders might be the result of contributions from environmental and occupational pesticide poisoning. PMID:26654853

  17. Genetic risks and genetic model specification.

    PubMed

    Zheng, Gang; Zhang, Wei; Xu, Jinfeng; Yuan, Ao; Li, Qizhai; Gastwirth, Joseph L

    2016-08-21

    Genetic risks and genetic models are often used in design and analysis of genetic epidemiology studies. A genetic model is defined in terms of two genetic risk measures: genotype relative risk and odds ratio. The impacts of choosing a risk measure on the resulting genetic models are studied in the power to detect association and deviation from Hardy-Weinberg equilibrium in cases using genetic relative risk. Extensive simulations demonstrate that the power of a study to detect associations using odds ratio is lower than that using relative risk with the same value when other parameters are fixed. When the Hardy-Weinberg equilibrium holds in the general population, the genetic model can be inferred by the deviation from Hardy-Weinberg equilibrium in only cases. Furthermore, it is more efficient than that based on the deviation from Hardy-Weinberg equilibrium in all cases and controls. PMID:27181372

  18. Genotyping Informatics and Quality Control for 100,000 Subjects in the Genetic Epidemiology Research on Adult Health and Aging (GERA) Cohort

    PubMed Central

    Kvale, Mark N.; Hesselson, Stephanie; Hoffmann, Thomas J.; Cao, Yang; Chan, David; Connell, Sheryl; Croen, Lisa A.; Dispensa, Brad P.; Eshragh, Jasmin; Finn, Andrea; Gollub, Jeremy; Iribarren, Carlos; Jorgenson, Eric; Kushi, Lawrence H.; Lao, Richard; Lu, Yontao; Ludwig, Dana; Mathauda, Gurpreet K.; McGuire, William B.; Mei, Gangwu; Miles, Sunita; Mittman, Michael; Patil, Mohini; Quesenberry, Charles P.; Ranatunga, Dilrini; Rowell, Sarah; Sadler, Marianne; Sakoda, Lori C.; Shapero, Michael; Shen, Ling; Shenoy, Tanu; Smethurst, David; Somkin, Carol P.; Van Den Eeden, Stephen K.; Walter, Lawrence; Wan, Eunice; Webster, Teresa; Whitmer, Rachel A.; Wong, Simon; Zau, Chia; Zhan, Yiping; Schaefer, Catherine; Kwok, Pui-Yan; Risch, Neil

    2015-01-01

    The Kaiser Permanente (KP) Research Program on Genes, Environment and Health (RPGEH), in collaboration with the University of California—San Francisco, undertook genome-wide genotyping of >100,000 subjects that constitute the Genetic Epidemiology Research on Adult Health and Aging (GERA) cohort. The project, which generated >70 billion genotypes, represents the first large-scale use of the Affymetrix Axiom Genotyping Solution. Because genotyping took place over a short 14-month period, creating a near-real-time analysis pipeline for experimental assay quality control and final optimized analyses was critical. Because of the multi-ethnic nature of the cohort, four different ethnic-specific arrays were employed to enhance genome-wide coverage. All assays were performed on DNA extracted from saliva samples. To improve sample call rates and significantly increase genotype concordance, we partitioned the cohort into disjoint packages of plates with similar assay contexts. Using strict QC criteria, the overall genotyping success rate was 103,067 of 109,837 samples assayed (93.8%), with a range of 92.1–95.4% for the four different arrays. Similarly, the SNP genotyping success rate ranged from 98.1 to 99.4% across the four arrays, the variation depending mostly on how many SNPs were included as single copy vs. double copy on a particular array. The high quality and large scale of genotype data created on this cohort, in conjunction with comprehensive longitudinal data from the KP electronic health records of participants, will enable a broad range of highly powered genome-wide association studies on a diversity of traits and conditions. PMID:26092718

  19. 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.

  20. 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

  1. 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

  2. Assessment of 1,3-butadiene epidemiology studies.

    PubMed Central

    Ott, M G

    1990-01-01

    Positive carcinogenicity studies in mice and rats have led to concerns that 1,3-butadiene may be carcinogenic in humans under exposure conditions that have existed in occupational settings and perhaps exist today. The principal settings of interest are the styrene-butadiene rubber (SBR) manufacturing industry, which uses large quantities of 1,3-butadiene, and the 1,3-butadiene monomer industry. The potential for 1,3-butadiene exposure is highest during monomer transfer operations and is lowest in finishing areas of polymerization plants where the polymer products are processed. Three large cohort mortality studies have been conducted in the SBR and monomer producing industries since 1980. These studies, which examined the mortality experience of over 17,000 men employed in one monomer and 10 SBR facilities, are the subject of this review. All but one of the facilities began operations during the early 1940s. The mortality experience observed within these employee cohorts is comparable to that seen in other long-term studies of men employed in the petroleum, chemical, and rubber industries for all causes of death, total malignant neoplasms, and for the specific cancers seen in excess in the toxicologic studies. This paper discusses discrepant findings observed in more detailed analyses within individual cohorts and among employment subgroups, as well as selected limitations of the particular studies. Additional efforts to refine 1,3-butadiene exposure categories are needed. Within the context of sample size limitations inherent in these studies, there is currently inadequate evidence to establish a relationship between cancer mortality outcomes and 1.3-butadiene exposure in humans. PMID:2205483

  3. 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

  4. Epidemiology of toxoplasmosis in white tailed deer (Odocoileus virginianus): occurrence, congenital transmission, correlates of infection, isolation, and genetic characterization of Toxoplasma gondii

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The prevalence of Toxoplasma gondii in white tailed deer (WTD) in the USA is high, but little is known of the epidemiology of toxoplasmosis in this host. In the present study, we compared T. gondii seroprevalence from 531 WTD collected in 2012 and 2013 from a Metropolitan Park in Ohio, and and 485 W...

  5. 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

  6. An epidemiological study on pattern and incidence of mandibular fractures.

    PubMed

    Natu, Subodh S; Pradhan, Harsha; Gupta, Hemant; Alam, Sarwar; Gupta, Sumit; Pradhan, R; Mohammad, Shadab; Kohli, Munish; Sinha, Vijai P; Shankar, Ravi; Agarwal, Anshita

    2012-01-01

    Mandible is the second most common facial fracture. There has been a significant increase in the number of cases in recent years with the advent of fast moving automobiles. Mandibular fractures constitute a substantial proportion of maxillofacial trauma cases in Lucknow. This study was undertaken to study mandibular fractures clinicoradiologically with an aim to calculate incidence and study pattern and the commonest site of fractures in population in and around Lucknow. Patient presenting with history of trauma at various centers of maxillofacial surgery in and around Lucknow were included in this study. Detailed case history was recorded followed by thorough clinical examination, and radiological interpretation was done for establishing the diagnosis and the data obtained was analyzed statistically. Out of 66 patients with mandibular fractures, highest percentage was found in 21-30 years of age with male predominance. Road traffic accidents were the most common cause of fracture with parasymphysis being commonest site. Commonest combination was parasymphysis with subcondyle. There was no gender bias in etiology with number of fracture sites. The incidence and causes of mandibular fracture reflect trauma patterns within the community and can provide a guide to the design of programs geared toward prevention and treatment. PMID:23227327

  7. EFFECT OF CIGARETTE SMOKING IN EPIDEMIOLOGICAL STUDIES OF LUNG CANCER

    EPA Science Inventory

    This paper describes a method for adjusting the analysis of occupational-environmental lung cancer risks for the effects of cigarette smoking in cohort and case control studies. he method uses a function that relates an individual's death rate to his age and cigarette smoking his...

  8. Optimal designs for epidemiologic longitudinal studies with binary outcomes.

    PubMed

    Mehtälä, Juha; Auranen, Kari; Kulathinal, Sangita

    2015-12-01

    Alternating presence and absence of a medical condition in human subjects is often modelled as an outcome of underlying process dynamics. Longitudinal studies provide important insights into research questions involving such dynamics. This article concerns optimal designs for studies in which the dynamics are modelled as a binary continuous-time Markov process. Either one or both the transition rate parameters in the model are to be estimated with maximum precision from a sequence of observations made at discrete times on a number of subjects. The design questions concern the choice of time interval between observations, the initial state of each subject and the choice between number of subjects versus repeated observations per subject. Sequential designs are considered due to dependence of the designs on the model parameters. The optimal time spacing can be approximated by the reciprocal of the sum of the two rates. The initial distribution of the study subjects should be taken into account when relatively few repeated samples per subject are to be collected. A study with a reasonably large size should be designed in more than one phase because there are then enough observations to be spent in the first phase to revise the time spacing for the subsequent phases. PMID:22170892

  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 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…

  11. Maltreatment and Disabilities: A Population-based Epidemiological Study.

    ERIC Educational Resources Information Center

    Sullivan, Patricia M.; Knutson, John F.

    2000-01-01

    This study reviewed merged records of children (N=40,211, 3,262 disabled) in Omaha, Nebraska, during 1994-95. An electronic merger of school records with child abuse, foster care, and police records was followed by a review of maltreatment incidents. Findings indicated a 9 percent prevalence rate of maltreatment for nondisabled children and a 31…

  12. Hearing Impairment in 2008: a compilation of available epidemiological studies.

    PubMed

    Pascolini, Donatella; Smith, Andrew

    2009-01-01

    A data bank of prevalence of hearing impairment for monitoring and implementation of programmes at national or global level and for the estimate of the global burden has been established. A systematic search was conducted of random-sample population-based studies of bilateral hearing impairment with clearly defined hearing threshold levels. Fifty-three studies from 31 countries from all WHO regions were found to meet the selection criteria. The prevalence of mild and disabling hearing impairment and other details from the studies are reported by WHO region. Although a large number of studies were found, only a small number among them were suitable surveys of prevalence of bilateral hearing impairment in the general population. Hearing impairment is a major disability that should be monitored at all ages: more population-based surveys are needed in all regions of the world. Utilization of the WHO protocol is recommended for collection and analysis of data in standard ways; especially recommended is the use of WHO threshold levels and to report the prevalence of bilateral impairment, both of which required to calculate burden. PMID:19444763

  13. Genetic studies in relation to kuru: an overview.

    PubMed

    Goldfarb, L G; Cervenakova, L; Gajdusek, D C

    2004-06-01

    Kuru is a subacute neurodegenerative disease presenting with limb ataxia, dysarthria, and a shivering tremor. The disease progress to complete motor and mental incapacity and death within 6 to 24 months. Neuropathologically, a typical pattern of neuronal loss, astrocytic and microglial proliferation, characteristic "kuru-type" amyloid plaques, and PrP deposits in the cerebral cortex and cerebellum are observed. Kuru is the prototype of a group of human transmissible spongiform encephalopathies (TSEs), or "prion" diseases, that include hereditary, sporadic and infectious forms. The latest member of this group, the variant Creutzfeldt-Jakob disease (vCJD), linked to transmission of bovine spongiform encephalopathy (BSE) to humans, shows features similar to kuru. Kuru has emerged at the beginning of the 1900s in a small indigenous population of New-Guinean Eastern Highlands, reached epidemic proportions in the mid-1950s and disappeared progressively in the latter half of the century to complete absence at the end of the 1990s. Early studies made infection, the first etiologic assumption, seem unlikely and led to a hypothesis that kuru might be a genetically determined or genetically mediated illness. After transmissibility of kuru had been discovered and all major epidemiologic phenomena adequately explained by the spread of an infectious agent with long incubation period through the practice of cannibalism, the pattern of occurrence still continued to suggest a role for genetic predisposition. Recent studies indicate that individuals homozygous for Methionine at a polymorphic position 129 of the prion protein were preferentially affected during the kuru epidemic. The carriers of the alternative 129Met/Val and 129Val/Val genotypes had a longer incubation period and thus developed disease at a later age and at a later stage of the epidemic. Observations made during the kuru epidemic are helpful in the understanding of the current vCJD outbreak, and vice versa clinical

  14. [The Oradea study regarding the epidemiology factors in ischemic cardiopathy].

    PubMed

    Pop, E; Popa, I; Bolcaş, D; Sirca, D; Simon, F; Costin, V; Balaj, V; Micle, T; Săvulescu, I H; Elenes, S; Negru, M; Cazacu, G; Popper, A; Gerhardt, L; Zavornic, E; Anton, N; Erdös, I; Frăţilă, H; Nica, V; Mesaroş, P; Jozsa, P; Lupu, D; David, D; Derecskey, E; Man, C; Palfi, E; Vass, H L

    1981-01-01

    Cholesterolemia in a population of 100482 inhabitants of the Bihor district, subjected to screening for the risk factors in ischemic cardiopathy were studied. Together with hyperlipidemias other risk factors were detected: arterial hypertension, obesity, diabetes mellitus, smoking, ischemic alterations of the electrocardiogram, the influence of the noxious agents present at the working place, of the blood groups and disturbances of the menstrual cycle. The mean cholesteremia is of 205 ± 43.7 mgr% (M = 207 ± 43.7 mgr%; F = 204 ± 43.5 mgr%). The prevalence of cholesterolemia, in comparison with the higher normal limits in each age group over 15 years of age, is in the entire studied series, of 13.5%. The population in whom cholesterolemia exceeds 250 mgr% represents 13.92%. PMID:25528799

  15. Dental Anxiety Among Adults: An Epidemiological Study in South India

    PubMed Central

    Appukuttan, Devapriya; Subramanian, Sangeetha; Tadepalli, Anupama; Damodaran, Lokesh Kumar

    2015-01-01

    Background: Dental anxiety is a major barrier for dental care utilization. Hence, identifying anxious individuals and their appropriate management becomes crucial in clinical practice. Aim: The study aims to assess dental anxiety, factors influencing dental anxiety, and anxiety towards tooth extraction procedure among patients attending a dental hospital in India. Materials and Methods: The study sample consisted of 1,148 consecutive patients aged 18-70 years. The assessment tools consisted of a consent form, history form, a questionnaire form containing the Modified Dental Anxiety Scale (MDAS) which was used to assess the level of dental anxiety, and an additional question on anxiety towards dental extraction procedure. Results: Among the study group, 63.7% were men and 36.3% were women. Based on the MDAS score, 45.2% of the participants were identified to be less anxious, 51.8% were moderately or extremely anxious, and 3% were suffering from dental phobia. Mean MDAS total score was 10.4 (standard deviation (SD) = 3.91). Female participants and younger subjects were more anxious (P < 0.001). Subjects who were anxious had postponed their dental visit (P < 0.001). Participants who had negative dental experience were more anxious (P < 0.05). Notably, 82.6% reported anxiety towards extraction procedure. Significant association was seen between anxiety towards extraction procedure and the respondents gender (P < 0.05), age (P < 0.001), education level (P < 0.05), employment status (P < 0.001), income (P < 0.001), self-perceived oral health status (P < 0.05), and their history of visit to dentist (P < 0.05). Conclusion: Significant percentage of population was suffering from dental anxiety in this study population. A plethora of factors like age, gender, education level, occupation, financial stability, and previous bad dental experience influences dental anxiety to various levels. Extraction followed by drilling of tooth and receiving local anesthetic injection

  16. Descriptive Epidemiology of the Multicenter ACL Revision Study (MARS) Cohort

    PubMed Central

    2013-01-01

    Background Revision anterior cruciate ligament (ACL) reconstruction has worse outcomes than primary reconstructions. Predictors for these worse outcomes are not known. The Multicenter ACL Revision Study (MARS) Group was developed to perform a multisurgeon, multicenter prospective longitudinal study to obtain sufficient subjects to allow multivariable analysis to determine predictors of clinical outcome. Purpose To describe the formation of MARS and provide descriptive analysis of patient demographics and clinical features for the initial 460 enrolled patients to date in this prospective cohort. Study Design Cross-sectional study; Level of evidence, 2. Methods After training and institutional review board approval, surgeons began enrolling patients undergoing revision ACL reconstruction, recording patient demographics, previous ACL reconstruction methods, intra-articular injuries, and current revision techniques. Enrolled subjects completed a questionnaire consisting of validated patient-based outcome measures. Results As of April 1, 2009, 87 surgeons have enrolled a total of 460 patients (57% men; median age, 26 years). For 89%, the reconstruction was the first revision. Mode of failure as deemed by the revising surgeon was traumatic (32%), technical (24%), biologic (7%), combination (37%), infection (<1%), and no response (<1%). Previous graft present at the time of injury was 70% autograft, 27% allograft, 2% combination, and 1% unknown. Sixty-two percent were more than 2 years removed from their last reconstruction. Graft choice for revision ACL reconstruction was 45% autograft, 54% allograft, and more than 1% both allograft and autograft. Meniscus and/or chondral damage was found in 90% of patients. Conclusion The MARS Group has been able to quickly accumulate the largest revision ACL reconstruction cohort reported to date. Traumatic reinjury is deemed by surgeons to be the most common single mode of failure, but a combination of factors represents the most

  17. A proposal to facilitate weight-of-evidence assessments: Harmonization of Neurodevelopmental Environmental Epidemiology Studies (HONEES)

    PubMed Central

    Youngstrom, Eric; Kenworthy, Lauren; Lipkin, Paul H.; Goodman, Michael; Squibb, Katherine; Mattison, Donald R.; Anthony, Laura Gutermuth; Makris, Susan L.; Bale, Ambuja S.; Raffaele, Kathleen C.; LaKind, Judy S.

    2011-01-01

    The ability to conduct weight-of-evidence assessments to inform the assessment of potential environmental neurotoxicants is limited by lack of comparability of study methods, data analysis, and reporting. There is a need to establish consensus guidelines for conducting, analyzing, and reporting neurodevelopmental environmental epidemiologic studies, while recognizing that consistency is likewise needed for epidemiology studies examining other health outcomes. This paper proposes a set of considerations to be used by the scientific community at-large as a tool for systematically evaluating the quality of proposed and/or published studies in terms of their value for weight-of-evidence assessments. Particular emphasis is placed on evaluating the sensitivity and specificity of neurodevelopmental function tests, as these characteristics directly affect the risk of false positive and false negative decisions at the level of the individual, thus influencing the risk of incorrect conclusions at the level of study findings. The proposed considerations are the first step in what must be a larger consensus-based process and can serve to catalyze such a discussion. Achieving consensus in these types of endeavors is difficult; however, opportunities exist for further interdisciplinary discussion, collaboration, and research that will help realize this goal. Broad acceptance and application of such an approach can facilitate the expanded use of environmental epidemiology studies of potential neurodevelopmental toxicants in the protection of public health, and specifically children's health. PMID:21315817

  18. A proposal to facilitate weight-of-evidence assessments: Harmonization of Neurodevelopmental Environmental Epidemiology Studies (HONEES).

    PubMed

    Youngstrom, Eric; Kenworthy, Lauren; Lipkin, Paul H; Goodman, Michael; Squibb, Katherine; Mattison, Donald R; Anthony, Laura Gutermuth; Makris, Susan L; Bale, Ambuja S; Raffaele, Kathleen C; LaKind, Judy S

    2011-01-01

    The ability to conduct weight-of-evidence assessments to inform the evaluation of potential en