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Population Controls (population + control)
Kinds of Population Controls Selected AbstractsBURKINA FASO: Call for Population ControlAFRICA RESEARCH BULLETIN: ECONOMIC, FINANCIAL AND TECHNICAL SERIES, Issue 1 2009Article first published online: 9 MAR 200 No abstract is available for this article. [source] Population Control in India: Prologue to the Emergency PeriodPOPULATION AND DEVELOPMENT REVIEW, Issue 4 2006Matthew Connelly First page of article [source] Stratified case sampling and the use of family controlsGENETIC EPIDEMIOLOGY, Issue 3 2001Kimberly D. Siegmund Abstract We compare the asymptotic relative efficiency (ARE) of different study designs for estimating gene and gene-environment interaction effects using matched case-control data. In the sampling schemes considered, cases are selected differentially based on their family history of disease. Controls are selected either from unrelated subjects or from among the case's unaffected siblings and cousins. Parameters are estimated using weighted conditional logistic regression, where the likelihood contributions for each subject are weighted by the fraction of cases sampled sharing the same family history. Results showed that compared to random sampling, over-sampling cases with a positive family history increased the efficiency for estimating the main effect of a gene for sib-control designs (103,254% ARE) and decreased efficiency for cousin-control and population-control designs (68,94% ARE and 67,84% ARE, respectively). Population controls and random sampling of cases were most efficient for a recessive gene or a dominant gene with an relative risk less than 9. For estimating gene-environment interactions, over-sampling positive-family-history cases again led to increased efficiency using sib controls (111,180% ARE) and decreased efficiency using population controls (68,87% ARE). Using case-cousin pairs, the results differed based on the genetic model and the size of the interaction effect; biased sampling was only slightly more efficient than random sampling for large interaction effects under a dominant gene model (relative risk ratio = 8, 106% ARE). Overall, the most efficient study design for studying gene-environment interaction was the case-sib-control design with over-sampling of positive-family-history-cases. Genet. Epidemiol. 20:316,327, 2001. © 2001 Wiley-Liss, Inc. [source] The Golden Rule and the Potentiality Principle: Future Persons and Contingent InterestsJOURNAL OF APPLIED PHILOSOPHY, Issue 1 2004Kai M. A. Chan abstract,Duties to future persons are central to numerous key ethical issues including contraception, abortion, genetic selection, treatment of the environment, and population control. Nevertheless, we still seem to be lacking Parfit's ,Theory X', a general theory of beneficence whose appropriateness extends to future generations. Starting from the Golden Rule (TGR), R. M. Hare purportedly derived counterintuitive duties to potential people and ,the potentiality principle'. However, I argue that Hare's derivation involves a hidden and unjustifiable extension from TGR, and show how the most plausible form of TGR is compatible with multiple contradictory principles for the treatment of future persons. I appeal to our own preferences to argue that one extension of TGR follows the spirit of TGR, while the other is deeply implausible. Using the plausible extension, I derive a Contingent Interests Principle (CIP) that offers much promise as Parfit's elusive Theory X. In contrast to Hare's interpretation of TGR, this application provides solid justification for rejecting the potentiality principle. [source] ULTRASTRUCTURAL CHARACTERIZATION OF THE LYTIC CYCLE OF AN INTRANUCLEAR VIRUS INFECTING THE DIATOM CHAETOCEROS CF. WIGHAMII(BACILLARIOPHYCEAE) FROM CHESAPEAKE BAY, USA,JOURNAL OF PHYCOLOGY, Issue 4 2009Yoanna Eissler Numerous microalgal species are infected by viruses that have the potential to control phytoplankton dynamics by reducing host populations, preventing bloom formation, or causing the collapse of blooms. Here we describe a virus infecting the diatom Chaetoceros cf. wighamii Brightw. from the Chesapeake Bay. To characterize the morphology and lytic cycle of this virus, we conducted a time-course experiment, sampling every 4 h over 72 h following viral inoculation. In vivo fluorescence began to decline 16 h after inoculation and was reduced to <19% of control cultures by the end of experiment. TEM confirmed infection within the first 8 h of inoculation, as indicated by the presence of virus-like particles (VLP) in the nuclei. VLP were present in two different arrangements: rod-like structures that appeared in cross-section as paracrystalline arrays of hexagonal-shaped profiles measuring 12 ± 2 nm in diameter and uniformly electron-dense hexagonal-shaped particles measuring , 22,28 nm in diameter. Nuclei containing paracrystalline arrays were most prevalent early in the infection cycle, while cells containing VLP increased and then declined toward the end of the cycle. The proportion of nuclei containing both paracrystalline arrays and VLP remained relatively constant. This pattern suggests that rod-like paracrystalline arrays fragmented to produce icosahedral VLP. C. cf. wighamii nuclear inclusion virus (CwNIV) is characterized by a high burst size (averaged 26,400 viruses per infected cell) and fast generation time that could have ecological implications on C. cf. wighamii population control. [source] Responses of the cabbage seedpod weevil, Ceutorhynchus obstrictus (Marsham) (Coleoptera: Curculionidae), to seed treatments of canola (Brassica napus L.) with the neonicotinoid compounds clothianidin and imidaclopridPEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 12 2009Lloyd M Dosdall Abstract BACKGROUND: The cabbage seedpod weevil, Ceutorhynchus obstrictus (Marsham), is a major pest in the production of canola (Brassica napus L.) in North America and Europe, and effective population control is often essential for economical crop production. In North America, neonicotinoid insecticides have been used for several years in canola as seed treatments for reducing herbivory by flea beetles. The neonicotinoids clothianidin and imidacloprid were investigated to determine their effects on preimaginal development and on emergence of new-generation adults of C. obstrictus in comparison with effects of lindane, a chlorinated hydrocarbon seed treatment. RESULTS: Mean numbers of second- and third-instar larvae were significantly higher in plants seed-treated with lindane than in plants treated with the neonicotinoid compounds, even though weevil oviposition was similar for all treatments. Emergence of new-generation adults was reduced by 52 and 39% for plants seed-treated with clothianidin and imidacloprid, respectively, compared with emergence from plants treated with lindane. CONCLUSION: Seed treatment with both clothianidin and imidacloprid produced systemic insecticidal effects on larvae of C. obstrictus, with clothianidin slightly more effective than imidacloprid. Use of clothianidin or imidacloprid as seed treatments can comprise an important component in the integrated management of cabbage seedpod weevil in canola. Copyright © 2009 Society of Chemical Industry [source] The birth of biometric securityANTHROPOLOGY TODAY, Issue 2 2009Mark Maguire We are currently witnessing a rapid rise in biometric security. Borders are apparently becoming ,smart'; passports are becoming e-passports, and when you set out on your travels your data double is already at your destination. Access to airports and even continents will increasingly be determined not by your national citizenship but by the security of your identity. Biometric security has received little anthropological attention despite historical associations with the discipline. Here I wish to outline a brief genealogy of biometric security in order to argue that, beyond the apparent newness of the technology, key biometric technologies owe their origins to 19th-entury deployments and then as now they may be understood as a form of bio-governmentality in which the security of identity opens possibilities for population control. [source] Little evidence for different phenomenology in poststroke depressionACTA PSYCHIATRICA SCANDINAVICA, Issue 6 2010T. B. Cumming Cumming TB, Churilov L, Skoog I, Blomstrand C, Linden T. Little evidence for different phenomenology in poststroke depression. Objective:, It remains unclear whether mood depressive disorders after stroke have a distinct phenomenology. We evaluated the symptom profile of poststroke depression (PSD) and assessed whether somatic symptoms were reported disproportionately by stroke patients. Method:, The sample was 149 stroke patients at 18 months poststroke and 745 age- and sex-matched general population controls. A comprehensive psychiatric interview was undertaken and depression was diagnosed according to DSM-III-R criteria. Results:, Depressed controls reported more ,inability to feel' (P = 0.002) and ,disturbed sleep' (P = 0.008) than depressed stroke patients. Factor analysis of the 10 depressive symptoms identified two main factors, which appeared to represent somatic and psychological symptoms. There was no difference in scores on these two factors between stroke patients and controls. Conclusion:, Phenomenology of depression at 18 months poststroke is broadly similar but not the same as that described by controls. Somatic symptoms of depression were not over-reported by stroke patients. [source] PON1 L55M polymorphism is not a predictor of coronary atherosclerosis either alone or in combination with Q192R polymorphism in an Italian populationEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 1 2002M. Arca Abstract Background, The present study evaluated the role of the PON1 L55M polymorphism independently and in conjunction with the Q192R polymorphism on the risk of coronary atherosclerosis in an Italian population. Materials and methods, Three hundred and ninety-one subjects with significant coronary stenosis (> 50%) (coronary artery disease-positive; CAD+), 196 subjects with normal coronary arteries (< 10% stenosis) (CAD,) and 178 healthy controls were screened using a combination of polymerase chain reaction and restriction enzyme digestion. Results, In the pooled population, the frequencies of L and M alleles were 0·63 and 0·37, respectively; the most common haplotypes were QQ/LM (24·2%) and QR/LL (21·8%) and a strong linkage disequilibrium between L/55 and R/192 alleles was observed (D, = ,0·91; P < 0·0001). CAD+ subjects did not show any significant differences in the distribution of PON1,55 genotypes as compared to CAD, subjects and population controls (,2 = 1·5, P = 0·8). After controlling for other risk factors, the low-concentration M allele was not associated with a significant change of CAD risk (OR 1·02; 95% CI 0·80,1·29; P = 0·87). Moreover, the L55M polymorphism did not show any interaction with other risk factors such as smoking, diabetes, hypertension, low levels of high-density lipoprotein (HDL) or high ratios of low-density to high-density lipoproteins. The combination of L55M with the Q192R polymorphism did not show any effect on CAD risk. However, a marginal decrease in myocardial infarction risk was detected when QQ/MM carriers (OR 0·51; 95% CI 0·26,0·99; P = 0·048), but not LL/RR carriers, were compared with subjects not homozygous for an L or R allele. Conclusions, These findings did not indicate a major effect of the PON1 L55M polymorphism, either alone or in combination with the Q192R polymorphism, on CAD risk. Additional studies are needed for a better evaluation of the role of the 55/192 PON1 genotypes in combination on myocardial infarction risk. [source] Stratified case sampling and the use of family controlsGENETIC EPIDEMIOLOGY, Issue 3 2001Kimberly D. Siegmund Abstract We compare the asymptotic relative efficiency (ARE) of different study designs for estimating gene and gene-environment interaction effects using matched case-control data. In the sampling schemes considered, cases are selected differentially based on their family history of disease. Controls are selected either from unrelated subjects or from among the case's unaffected siblings and cousins. Parameters are estimated using weighted conditional logistic regression, where the likelihood contributions for each subject are weighted by the fraction of cases sampled sharing the same family history. Results showed that compared to random sampling, over-sampling cases with a positive family history increased the efficiency for estimating the main effect of a gene for sib-control designs (103,254% ARE) and decreased efficiency for cousin-control and population-control designs (68,94% ARE and 67,84% ARE, respectively). Population controls and random sampling of cases were most efficient for a recessive gene or a dominant gene with an relative risk less than 9. For estimating gene-environment interactions, over-sampling positive-family-history cases again led to increased efficiency using sib controls (111,180% ARE) and decreased efficiency using population controls (68,87% ARE). Using case-cousin pairs, the results differed based on the genetic model and the size of the interaction effect; biased sampling was only slightly more efficient than random sampling for large interaction effects under a dominant gene model (relative risk ratio = 8, 106% ARE). Overall, the most efficient study design for studying gene-environment interaction was the case-sib-control design with over-sampling of positive-family-history-cases. Genet. Epidemiol. 20:316,327, 2001. © 2001 Wiley-Liss, Inc. [source] Association of DLG5 variants with inflammatory bowel disease in the New Zealand caucasian population and meta-analysis of the DLG5 R30Q variant,INFLAMMATORY BOWEL DISEASES, Issue 9 2007Brian L. Browning PhD Abstract Background: Variants in the DLG5 gene have been associated with inflammatory bowel disease (IBD) in samples from some, but not all populations. In particular, 2 nonsynonymous single-nucleotide polymorphisms (SNPs), R30Q (rs1248696) and P1371Q (rs2289310), have been associated with an increased risk of IBD, and a common haplotype (called haplotype "A") has been associated with reduced risk. Methods: We genotyped R30Q, P1371Q, and a haplotype A tagging SNP (rs2289311) in a New Zealand Caucasian cohort of 389 Crohn's disease (CD) patients, 406 ulcerative colitis (UC) patients, and 416 population controls. Each SNP was tested for association with disease susceptibility and clinical phenotypes. We also performed a meta-analysis of R30Q data from published association studies. Results: The haplotype A tagging SNP was associated with reduced risk of IBD at the 0.05 significance level (P = 0.036) with an allelic odds ratio of 0.83 (95% confidence interval [CI]: 0.69,0.99). Association with haplotype A was strongest (odds ratio ,0.57) in UC patients with familial IBD or extraintestinal manifestations. The R30Q and P1371Q polymorphisms were not significantly associated with UC, CD, or IBD. Analysis of male and female data did not find any gender-specific associations. Meta-analysis gave no evidence of association of R30Q with IBD. Conclusions: Meta-analysis demonstrates that the minor allele of R30Q is not a risk factor for IBD across populations. This study provides some evidence that DLG5 haplotype A is associated with reduced risk of IBD in the New Zealand Caucasian population, but this association will need to be replicated in an independent sample. (Inflamm Bowel Dis 2007) [source] Maternal medication use and the risk of brain tumors in the offspring: The SEARCH international case-control studyINTERNATIONAL JOURNAL OF CANCER, Issue 5 2006Amanda H. Cardy Abstract N -nitroso compounds (NOC) have been associated with carcinogenesis in a wide range of species, including humans. There is strong experimental data showing that nitrosamides (R1NNO·COR2), a type of NOC, are potent neuro-carcinogens when administered transplacentally. Some medications are a concentrated source of amides or amines, which in the presence of nitrites under normal acidic conditions of the stomach can form NOC. Therefore, these compounds, when ingested by women during pregnancy, may be important risk factors for tumors of the central nervous system in the offspring. The aim of the present study was to test the association between maternal use of medications that contain nitrosatable amines or amides and risk of primary childhood brain tumors (CBT). A case-control study was conducted, which included 1,218 cases and 2,223 population controls, recruited from 9 centers across North America, Europe and Australia. Analysis was conducted for all participants combined, by tumor type (astroglial, primitive neuroectodermal tumors and other glioma), and by age at diagnosis (,5 years; >5 years). There were no significant associations between maternal intake of medication containing nitrosatable amines or amides and CBT, for all participants combined and after stratification by age at diagnosis and histological subtype. This is the largest case-control study of CBT and maternal medications to date. Our data provide little support for an association between maternal use of medications that may form NOC and subsequent development of CBT in the offspring. © 2005 Wiley-Liss, Inc. [source] The association of gingivitis and periodontitis with ischemic strokeJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 5 2004Christof E. Dörfer Abstract Objectives: The aim of this study was to assess the associations of different periodontal parameters with cerebral ischemia. Methods: In a case,control study, 303 consecutive patients with ischemic stroke or transient ischemic attack, and 300 representative population controls received a complete clinical and radiographic dental examination. Patients were examined on average 3 days after ischemia. The individual mean clinical attachment loss measured at four sites per tooth was used as indicator variable for periodontitis. Results: Patients had higher clinical attachment loss than population (p<0.001). After adjustment for age, gender, number of teeth, vascular risk factors and diseases, childhood and adult socioeconomic conditions and lifestyle factors, a mean clinical attachment loss >6 mm had a 7.4 times (95% confidence interval 1.55,15.3) a gingival index >1.2 a 18.3 times (5.84,57.26) and a radiographic bone loss a 3.6 times (1.58,8.28) higher risk of cerebral ischemia than subjects without periodontitis or gingivitis, respectively. Conclusion: Periodontitis is an independent risk factor for cerebral ischemia and acute exacerbation of inflammatory processes in the periodontium might be a trigger for the event of cerebral ischemia. [source] Long-term physical outcome in patients with septic shockACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 6 2009J. B. POULSEN Background: Limited information is available on physical function after septic shock. The aim of the present study was to assess the physical outcome in survivors 1 year after septic shock. Methods: The outcome status of all 174 adult patients admitted to a mixed ICU with the diagnosis septic shock in a 1-year period was registered. Survivors were interviewed about physical function and socioeconomic status using a questionnaire including the Short Form-36 survey. The pre-ICU-admission Functional Comorbidity Index (FCI) was also registered. Results: Of the 80 survivors, two were still hospitalised; thus, 78 were invited to participate and 70 replied (inclusion-rate 88%). Patients were followed up at median 351 days after hospital discharge. At follow-up the patients had a markedly reduced physical component summary score (PCS) compared with age- and sex-adjusted general population controls (36 vs. 47, P<0.0001). This was also observed in patients with no comorbidity before ICU admission (34 vs. 47, P<0.001). There was a negative correlation (r=,0.27, P=0.03) between pre-ICU-admission FCI values and the PCS at follow-up. According to 81% of the patients, loss of muscle mass was the main cause of decreased physical function. Only 43% (10 vs. 23, P=0.01) of the previously employed had returned to work, and the number of patients in need of home-based personal assistance had doubled (10/20, P=0.04). Conclusion: Physical function is substantially reduced in survivors of septic shock 1 year after discharge. [source] Intrinsic reproductive isolation between Trinidadian populations of the guppy, Poecilia reticulataJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 4 2006S. T. RUSSELL Abstract Although Trinidadian populations of the guppy, Poecilia reticulata, show considerable adaptive genetic differentiation, they have been assumed to show little or no reproductive isolation. We tested this assumption by crossing Caroni (Tacarigua River) and Oropuche (Oropuche R.) drainage populations from Trinidad's Northern Range, and by examining multiple aspects of reproductive compatibility in the F1, F2 and BC1 generations. In open-aquarium experiments, F1 males performed fewer numbers of mating behaviours relative to parental population controls. This is the first documentation of hybrid behavioural sterility within a species, and it suggests that such sterility may feasibly be involved in causing speciation. The crosses also uncovered hybrid breakdown for embryo viability, brood size and sperm counts. In contrast, no reductions in female fertility were detected, indicating that guppies obey Haldane's rule for sterility. Intrinsic isolation currently presents a much stronger obstacle to gene flow than behavioural isolation, and our results indicate that Trinidadian populations constitute a useful model for investigating incipient speciation. [source] Corticosteroid use and risk of hip fracture: a population-based case,control study in DenmarkJOURNAL OF INTERNAL MEDICINE, Issue 5 2003P. Vestergaard Abstract. Vestergaard P, Olsen ML, Paaske Johnsen S, Rejnmark L, Toft Sørensen H, Mosekilde L (Aarhus University Hospital, Denmark; and Aarhus and Aalborg University Hospitals; Aarhus, Denmark). Corticosteroid use and risk of hip fracture: a population-based case,control study in Denmark. J Intern Med 2003; 254: 486,493. Background. Corticosteroids (CS) are used in a wide range of conditions but have several possible adverse effects including an increased risk of osteoporotic fractures. Objective. To examine the association between cumulative CS dose and risk of hip fracture. Design. Population-based case,control design. Subjects and methods. A total of 6660 subjects with hip fracture and 33 272 age-matched population controls were identified using the County Hospital Discharge Registry in North Jutland County, Denmark and the Danish Central Personal Registry, respectively. Data on redeemed prescriptions for CS within the last 5 years before the index date were retrieved from a population-based prescription database, and recalculated to prednisolone equivalents. Cases and controls were categorized according to cumulative CS dose: (i) no use; (ii) <130 mg (e.g. equivalent to 30 mg of prednisolone for 4 days given for an acute exacerbation of asthma); (iii) 130,499 mg (e.g. equivalent to a short course of prednisolone of 450 mg for acute asthma); (iv) 500,1499 mg (e.g. equivalent to 7.5 mg prednisolone daily for 6 months or 800 ,g day,1 of inhaled budesonide for 1 year); and (v) ,1500 mg (e.g. equivalent to >4.1 mg day,1 for 1 year, a long-term high dose). Data were analysed using conditional logistic regression adjusted for potential confounders including gender, redeemed prescriptions for hormone replacement therapy, antiosteoporotic, anxiolytic, antipsychotic and antidepressant drugs. Results. Compared with never users, an increased risk of hip fracture was found for CS users, with increasing cumulative doses of any type of CS use during the preceding 5 years [adjusted odds ratio (OR) = 0.96, 95% confidence interval (CI) = 0.89,1.04] for <130 mg prednisolone; OR = 1.17 (CI = 1.01,1.35) for 130,499 mg; OR = 1.36 (CI = 1.19,1.56) for 500,1499 mg; and OR = 1.65 (CI = 1.43,1.92) for ,1500 mg. An increased risk was also found when the study population was stratified according to gender, age and type of CS (systemic or topical). Conclusions. Even a limited daily dose of CS (more than an average dose of approximately 71 ,g prednisolone per day) was associated with an increased risk of hip fracture. [source] A parallel analysis of individual and ecological data on residential radon and lung cancer in south-west EnglandJOURNAL OF THE ROYAL STATISTICAL SOCIETY: SERIES A (STATISTICS IN SOCIETY), Issue 1 2001Sarah Darby Parallel individual and ecological analyses of data on residential radon have been performed using information on cases of lung cancer and population controls from a recent study in south-west England. For the individual analysis the overall results indicated that the relative risk of lung cancer at 100 Bq m,3 compared with at 0 Bq m,3 was 1.12 (95% confidence interval (0.99, 1.27)) after adjusting for age, sex, smoking, county of residence and social class. In the ecological analysis substantial bias in the estimated effect of radon was present for one of the two counties involved unless an additional variable, urban,rural status, was included in the model, although this variable was not an important confounder in the individual level analysis. Most of the methods that have been recommended for overcoming the limitations of ecological studies would not in practice have proved useful in identifying this variable as an appreciable source of bias. [source] JOINTLY-DETERMINED ECOLOGICAL THRESHOLDS AND ECONOMIC TRADE-OFFS IN WILDLIFE DISEASE MANAGEMENTNATURAL RESOURCE MODELING, Issue 4 2007ELI P. FENICHEL ABSTRACT. We investigate wildlife disease management, in a bioeconomic framework, when the wildlife host is valuable and disease transmission is density-dependent. Disease prevalence is reduced in density-dependent models whenever the population is harvested below a host-density threshold a threshold population density below which disease prevalence declines and above which a disease becomes epidemic. In conventional models, the threshold is an exogenous function of disease parameters. We consider this case and find a steady state with positive disease prevalence to be optimal. Next, we consider a case in which disease dynamics are affected by both population controls and changes in human-environmental interactions. The host-density threshold is endogenous in this case. That is, the manager does not simply manage the population relative to the threshold, but rather manages both the population and the threshold. The optimal threshold depends on the economic and ecological trade-offs arising from the jointly-determined system. Accounting for this endogene-ity can lead to reduced disease prevalence rates and higher population levels. Additionally, we show that ecological parameters that may be unimportant in conventional models that do not account for the endogeneity of the host-density threshold are potentially important when host density threshold is recognized as endogenous. [source] Occupational wood dust exposure and the risk of laryngeal cancer: A population based case-control study in GermanyAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 9 2008Heribert Ramroth Abstract Background To investigate the effect of exposure to wood dust on the risk of laryngeal cancer. Methods A population-based case-control study on laryngeal cancer was conducted in South-West Germany between 1st of May 1998 to 31st of December 2000 with 257 histologically confirmed cases (236 males, 21 females), age 37 to 80 years, and 769 population controls (702 males, 67 females), 1:3 frequency matched by age and sex. Occupational exposures and other risk factors were obtained with face-to-face interviews using a detailed standardized questionnaire. The complete individual work history was assessed. Work conditions were obtained by job-specific questionnaires for selected jobs known to be associated with exposure to potential carcinogens. Additionally, a specific substance check-list was used as a method for exposure assessment. Results 43 (16.7%) cases (41 males, 2 females) and 107 (13.9%) controls (105 males, 2 females) reported wood dust exposure. Numbers were almost identical for two different methods of exposure assessment; however, the agreement of these methods was around 95%. A strong effect on laryngeal cancer risk after adjustment for smoking, alcohol and education was observed for high exposure to hardwood dust (OR,=,2.6, 95% CI 1.3--5.2) and to softwood dust (OR,=,2.2, 95% CI 1.1--4.2), as assessed by substance list. Conclusions Our findings for higher exposure to hardwood and softwood dust contribute to the evidence that wood dust, in particular from hardwood is an independent risk factor. Am. J. Ind. Med. 51:648,655, 2008. Published 2008 Wiley-Liss, Inc. [source] Occupation and risk of esophageal and gastric cardia adenocarcinoma,AMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 1 2002Lawrence S. Engel PhD Abstract Background Adenocarcinomas of the esophagus and gastric cardia have risen dramatically in incidence over the past few decades, however, little research has been conducted on the occupational risk factors for these cancers. Methods In this population-based case-control study, lifetime job histories were compared between cases of esophageal adenocarcinoma (n,=,283), gastric cardia adenocarcinoma (n,=,259), and population controls (n,=,689). Odds ratios (OR) and 95% confidence intervals (CI) for ever employment and by duration in various occupational and industrial categories were calculated using unconditional logistic regression. Results The risk of esophageal adenocarcinoma was elevated for persons ever employed in administrative support (OR,=,1.5; 95%CI,=,1.0,2.1); financial, insurance, and real estate (OR,=,1.6; 95%CI,=,1.0,2.4); and health services (OR,=,2.2; 95%CI,=,1.2,3.9). The risk of gastric cardia adenocarcinoma was increased among transportation workers (OR,=,1.7; 95%CI,=,1.1,2.6), as well as among carpenters (OR,=,1.8; 95%CI,=,0.9,3.9) and workers in the furniture manufacturing industry (OR,=,2.4; 95%CI,=,0.9,6.3). However, we observed few duration,response relations between length of employment in any category and cancer risk. Conclusions This study revealed associations of esophageal adenocarcinoma with employment in administrative support, health services, and a category of financial, insurance, and real estate industries, and of gastric cardia adenocarcinoma with transportation and certain woodworking occupations. Some of these findings may be due to the play of chance associated with the multiple comparisons made in this study. Our results suggest that, overall, workplace exposures play a minor role in the etiology and upward trend of esophageal and gastric cardia adenocarcinomas. Am. J. Ind. Med. 42:11,22, 2002. Published 2002 Wiley-Liss, Inc. [source] Burden of Medical Illness in Drug- and Alcohol-dependent Persons Without Primary CareTHE AMERICAN JOURNAL ON ADDICTIONS, Issue 1 2004Israel De Alba M.D., M.P.H. Little is known about the frequency, severity, and risk factors for disease in drug- and alcohol-dependent persons without primary medical care. Our aims are to assess the burden of medical illness, identify patient and substance dependence characteristics associated with worse physical health, and compare measures of illness burden in this population. This was accomplished through a cross-sectional study among alcohol-, heroin- or cocaine-dependent persons without primary medical care who were admitted to an urban inpatient detoxification unit. The mean age of these patients was 35.7 (SD 7.8) years; 76% were male and 46% were Black. Forty-five percent reported being diagnosed with a chronic illness, and 80% had prior medical hospitalizations. The mean age-adjusted SF-36 Physical Component Summary (PCS) score was lower than the general U.S. population norm (44.1 vs 50.1; p < 0.001). In multivariable analysis, female gender (adjusted mean change in PCS score: ,3.71 points, p = .002), problem use of hallucinogens (,3.51, p = 0.013), heroin (,2.94, p = 0.008), other opiates (,3.20, p = .045), living alone (,3.15, p = .023), having medical insurance (,2.26, p = 0.014) and older age (,.22 points per year, p = 0.001) were associated with worse health. From these data, it seems that alcohol- and drug-dependent persons without primary medical care have a substantial burden of medical illness compared to age- and gender-matched U.S. population controls. While the optimal measure of medical illness burden in this population is unclear, a variety of health measures document this medical illness burden in addicted persons. [source] Analysis of RYR1 Haplotype Profile in Patients with Malignant HyperthermiaANNALS OF HUMAN GENETICS, Issue 1 2009D. Carpenter Summary This study represents a new approach to characterising patients at risk of malignant hyperthermia (MH) through the use of a recently published method for identifying high-risk haplotypes in candidate genes. We present analysis based upon the largest standardised and genotyped database of MH patients worldwide. We used unphased RYR1 SNP data directly to (1) assess RYR1 haplotype frequency differences between susceptible cases and control groups and (2) analyse population-based association via clustering of RYR1 haplotypes based on disease risk. Our results show a significant difference in RYR1 haplotype frequency between susceptible cases and UK Caucasian population controls. Furthermore we identify a high-risk cluster of haplotypes that is associated with the commonest UK MH mutation p.G2434R/c.7300G>A. These results demonstrate the applicability of this new and practical method for population based association analysis. [source] Do rheumatoid arthritis and lymphoma share risk factors?: A comparison of lymphoma and cancer risks before and after diagnosis of rheumatoid arthritisARTHRITIS & RHEUMATISM, Issue 5 2010Karin Hellgren Objective Patients with rheumatoid arthritis (RA), in particular those with the most severe disease, are at increased risk of developing malignant lymphoma. Whether this increase is entirely a consequence of the RA disease and/or its treatment or is reflective of shared susceptibility to the two diseases remains unclear. We undertook this study to assess whether patients with RA are already at increased risk of lymphoma or of other cancers before the diagnosis of RA, and if the relative risk increases with time since RA diagnosis. Methods Patients with incident RA (symptom duration <1 year) (n = 6,745) registered in the Swedish Early Arthritis Registry from 1997 through 2006 were identified. For each patient, 5 general population controls were randomly matched by sex, age, marital status, and residence (n = 33,657). For all study subjects, inclusion in the nationwide Swedish Cancer Register in 1958,2006 was determined. Relative risks (RRs) (with 95% confidence intervals [95% CIs]) of lymphoma and of cancer overall, before and after diagnosis of RA, were estimated using conditional logistic regression and Cox regression, respectively. Results Before diagnosis of RA, there was no observed increase in the risk of lymphoma (RR [odds ratio] 0.67 [95% CI 0.37,1.23]) or other cancers (RR 0.78 [95% CI 0.70,0.88]). During the first 10 years following diagnosis of RA, the overall RR (hazard ratio) of lymphoma development was 1.75 (95 % CI 1.04,2.96). Conclusion These findings indicate that overall, a history of cancer, including lymphoma, does not increase the risk of subsequent RA development. Shared susceptibility to RA and lymphoma may thus be of limited importance. In contrast, increased lymphoma risks were observed within the first decade following RA diagnosis. [source] No increased occurrence of ischemic heart disease prior to the onset of rheumatoid arthritis: Results from two Swedish population-based rheumatoid arthritis cohortsARTHRITIS & RHEUMATISM, Issue 10 2009Marie E. Holmqvist Objective To investigate the relative importance of shared etiologies for rheumatoid arthritis (RA) and ischemic heart disease (IHD) in terms of the well-known increased risk of IHD in patients with RA, by assessing the occurrence of IHD up until the time of the onset of the first symptoms of RA. Methods We assessed the prevalence of a history of IHD, myocardial infarction (MI), and angina pectoris before the onset of RA symptoms in 2 large population-based case,control studies. Patients with newly diagnosed RA according to the criteria of the American College of Rheumatology were included as cases. We used data from the Swedish Early Arthritis Register study and the Swedish Epidemiologic Investigation of Rheumatoid Arthritis case,control study and from general population controls. Information on IHD, MI, and angina pectoris was obtained from the nationwide Hospital Discharge Register and from self reports. We calculated odds ratios (ORs) and 95% confidence intervals (95% CIs) to compare the prevalence of a history of IHD/MI/angina pectoris among patients with RA with that among population controls. Results We could not detect any increased occurrence of IHD, MI, or angina pectoris before the onset of symptoms of RA, regardless of whether data on IHD were obtained from the Hospital Discharge Register or were self reported. As detected in the Hospital Discharge Register, the OR for IHD overall was 1.0 (95% CI 0.9,1.1), the OR for MI was 1.0 (95% CI 0.9,1.1), and the OR for angina pectoris was 1.0 (95% CI 0.9,1.2). Conclusion Shared risk factors or susceptibilities for RA and IHD are likely to contribute less than RA-related factors to the increased occurrence of IHD in patients with manifest RA. Nonetheless, the existence of shared factors associated with longer latency until the occurrence of IHD cannot be excluded. [source] Investigation of the MHC2TA gene, associated with rheumatoid arthritis in a Swedish population, in a UK rheumatoid arthritis cohortARTHRITIS & RHEUMATISM, Issue 11 2006Stephen Eyre Objective A recent study of rheumatoid arthritis (RA) showed an association with a functional single-nucleotide polymorphism (SNP) mapping to the promoter region of the MHC2TA gene on chromosome 16p13 in a Swedish population. Interestingly, evidence for linkage to this region has been detected previously in a subgroup of UK RA families carrying 2 copies of shared epitope (SE) alleles. Therefore, we undertook this study to investigate the association of the MHC2TA gene promoter with RA in a UK Caucasian population. Methods Association with 5 SNPs spanning the promoter region of the MHC2TA gene was investigated in 813 UK RA patients and 532 population controls. Association with a functional putative RA-causal polymorphism (,168*G/A [rs3087456]) was tested in a total of 1,401 UK RA patients and 2,475 controls. Genotyping was performed using a Sequenom MassArray platform. Estimated haplotype frequencies were generated using the expectation-maximization algorithm and compared between patients and controls. Results All SNPs were in Hardy-Weinberg equilibrium. No evidence for association was found, either with the putative RA-causal polymorphism (,168*G/A) or with the other SNPs tested. Haplotype analysis revealed extensive linkage disequilibrium across the promoter region but no evidence for association. Stratifying the data set by carriage of SE alleles did not alter the conclusions. Conclusion A functional polymorphism of the MHC2TA gene locus previously associated with RA in a European population has not been associated with RA in a UK population. These findings do not provide support for the notion that this gene plays a major role in the etiology of RA. [source] Changes in Health Assessment Questionnaire disability scores over five years in patients with rheumatoid arthritis compared with the general populationARTHRITIS & RHEUMATISM, Issue 10 2006Tuulikki Sokka Objective To analyze longitudinal data over 5 years for changes in Health Assessment Questionnaire (HAQ) scores in patients with rheumatoid arthritis (RA) and age- and sex-matched controls from the general population. Methods In 2000 and 2005, identical self-report questionnaires were mailed to a cohort of patients with RA and control cohort from the community. The questionnaire included the HAQ, which was used to assess functional status. Changes in HAQ scores over 5 years were analyzed. Results In 2000, 73% of 1,495 patients with RA and 77% of 2,000 general population controls responded to the questionnaire. In 2005, 84% of 2,022 patients with RA and 77% of 1,817 controls responded. A total of 863 patients with RA and 1,176 community controls responded in both 2000 and 2005 and were included in the analyses. Mean baseline HAQ scores were significantly higher in patients with RA than in controls (0.71 versus 0.17; P < 0.001). Over 5 years, the HAQ scores increased by 0.01 units per year in both the RA cohort and the community population; in both cohorts, the net change was primarily attributable to individuals over age 70 years. Changes in HAQ scores were similar in patients and controls who had low HAQ scores at baseline. Female patients with baseline HAQ scores of ,0.5 had less potential for improvement than did controls. Among subjects in both groups who had HAQ scores >2, death was a common outcome over the next 5 years. Conclusion Currently, progression of functional disability among patients with RA and among persons in the general population is largely explained by the aging process. Our results showing stable function scores over 5 years in most patients with RA who are younger than age 70 years provide further evidence of improved status of RA patients today compared with the major declines observed in previous decades. [source] Comparison of the performance of serological kits for Helicobacter pylori infection with European and Asian study populationsCLINICAL MICROBIOLOGY AND INFECTION, Issue 11 2006T. T. H. Hoang Abstract Most commercial kits for the detection of Helicobacter pylori were developed and validated with Western populations, and some have been found to perform less well with Asian populations. This study compared the performances of three serological kits with Swedish and Vietnamese peptic ulcer patients and asymptomatic individuals. The Pyloriset EIA-GIII and HM-CAP ELISA kits indicated that Asian populations had lower antibody titres to H. pylori than European populations. Despite the difference, the Pyloriset EIA-GIII kit performed well with Vietnamese peptic ulcer patients and population controls. The HM-CAP ELISA kit had a significantly lower performance with Asian populations that could not be improved by adjustments to the cut-off level. The Helicoblot 2.1 immunoblot kit performed equally well with Vietnamese and Swedish populations, although the response rate to the 35-kDa band was significantly lower with Vietnamese individuals. [source] | |||||||||||||||||||