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Recent Exposure (recent + exposure)
Selected AbstractsPersistent organochlorine residues and their bioaccumulation profiles in resident and migratory birds from North VietnamENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 10 2002Tu Binh Minh Abstract Concentrations of persistent organochlorines (OCs), such as polychlorinated biphenyls (PCBs), 1 1,1-trichloro-2,2-bis(p -chlorophenyl)ethane (DDT) and its metabolites (DDTs), hexachlorocyclohexane isomers (HCHs), hexachlorobenzene (HCB), and chlordane compounds (CHLs), were determined in whole-body homogenates of resident and migratory birds collected from the Red River estuary, North Vietnam, during March and October 1997. Contamination pattern was in the order of DDTs > PCBs > HCHs > CHLs > HCB in both resident and migratory birds. Residue concentrations, according to the feeding habit, showed little variability, which may reflect relatively similar trophic levels of the bird species analyzed. Resident birds accumulated greater concentrations of DDTs as compared to migrants. In contrast, HCH residues were greater in migratory species. Higher proportions of p,p,-DDT to total DDT concentrations were found in many species of residents and migrants, indicating recent exposure to technical DDT in northern Vietnam. Congener-specific PCB analysis showed the predominance of penta- and hexachlorobiphenyls in all the species analyzed. Estimation of hepatic microsomal enzyme activities suggested higher metabolic capacity for PCB congeners in shore birds from Vietnam as compared to higher-trophic predator birds and marine mammals. Comparison of OC residues in avian species in Asia-Pacific revealed that DDT residues in resident birds in North Vietnam are among the highest values reported for the countries surveyed, suggesting recent usage of DDT in Vietnam. Available data for birds, fish, and bivalves from the recent Asia-Pacific Mussel Watch Program suggested that Vietnam might be a potential source of DDT contamination in Asian developing countries. To our knowledge, this is the first study of the OC accumulation in avian species from Vietnam. [source] Preliminary study of mucosal IgA in the equine small intestine: specific IgA in cases of acute grass sickness and controlsEQUINE VETERINARY JOURNAL, Issue 5 2007F. G. NUNN Summary Reasons for performing study: There is much evidence to suggest that group III Clostridium botulinum (types C and D) are involved in the aetiology of equine grass sickness (EGS). Antibodies have been detected previously in the blood and high levels associated with resistance to disease. Specific mucosal antibodies in the gastrointestinal (GI) tract are likely to be important in protection, and this study was performed to ascertain if such antibodies could be detected and if their levels were related to disease state. Objectives: To develop a method for quantifying IgA antibodies to C. botulinum types C and D in the GI tract of horses and to relate antibody levels to disease status. Methods: Samples of tissue (n = 25: 6 duodenum, 7 jejunum and 12 ileum) were taken from acute grass sickness (AGS) cases and from control horses (n = 12; 4 samples from each site) at post mortem. They were extracted with the detergent saponin in the presence of protease inhibitors and assayed for total IgA, for specific IgA against botulinum neurotoxins types C and D (BoNT/C or BoNT/D), and against surface antigens of a BoNT/C negative strain of C. botulinum type C (SA) and of Clostridium tetani (TetSA), as a control. Specific IgA was expressed as percentage total IgA. Results: Compared to controls, significantly higher levels of specific IgA against BoNT/C were detected in the jejunum (P = 0.04) and ileum (P = 0.02) of AGS cases. Similarly, higher specific levels against BoNT/D were demonstrated in duodenum (P = 0.01) and jejunum (P = 0.02). Significantly higher levels of IgA against SA were demonstrated only in duodenal samples (P = 0.01). Conclusions: Levels of IgA antibody to BoNTs in control horses were at near undetectable levels, suggesting no recent exposure to toxins. In AGS cases, significantly higher levels of specific IgA were detected predominantly in jejunum and ileum. Potential relevance: If specific IgA is protective then any successful vaccine for EGS should induce a mucosal response. [source] Treatment emergent mania responding to valproate in a Chinese female adolescent population with eating disorders: A case seriesEUROPEAN EATING DISORDERS REVIEW, Issue 6 2008Phern Chern Tor Abstract Eating disorders are commonly associated with depressive symptoms. In an adolescent and binge eating population fluoxetine is commonly used to treat co-morbid depression associated with eating disorders. In some patients this may precipitate treatment emergent mania (TEM). Risk factors in the adolescent population include being older, female, having a longer duration of illness, more previous mood episodes, a higher prevalence of subclinical hypothyroidism, early-onset anxiety and recent exposure to a mood-elevating agent. Diagnosis and management of these co-morbid conditions is challenging due to the overlapping symptomatology and the adverse effects of both conditions complicating pharmacological management. This is illustrated with three cases in a Chinese female adolescent population that experienced TEM while on fluoxetine and responded to valproate. Copyright © 2008 John Wiley & Sons, Ltd and Eating Disorders Association. [source] Prevalence of high antibody titers of pertussis in Turkey: reflection of circulating microorganism and a threat to infantsJOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 3 2007Berrin Esen Abstract Acute pertussis infection among adults can cause its transmission to the larger population, especially to infants and young children, who can develop severe disease. In order to determine an age-dependent pertussis immune response, anti-pertussis toxin (PT) antibody was detected by the indirect enzyme-linked immunosorbent assay (ELISA) method in serum samples from 2,085 healthy subjects ranging in age from 6 months to ,60 years. Also included in the evaluation were responses to a questionnaire including sociodemographic characteristics, vaccination, and infection history. Titers of 50,99 ELISA units (EU)/mL and of ,100,EU/mL were accepted as indicative for recent exposure or infection. In addition, 30,EU/mL was estimated to be a sufficient titer in women of childbearing age to protect their newborns until administration of their first dose of pertussis vaccine. After the age of 4,5 years, presence of high-titered antibodies that increase with age might be a reflection of circulating infection and indicate the magnitude of the threat to infants. According to the questionnaires, in the groups younger than 15 years old, three to four doses of diphtheria toxoid-whole cell pertussis-tetanus toxoid (DwPT) were administered in 47.2 to 77.4%, 91.2 to 100.0%, and 83.5 to 100.0% of participants in Diyarbakir, Samsun, and Antalya, respectively. In addition, up to half of the expectant mothers we studied lacked a sufficient level of estimated antibody titers. To protect infants from life-threatening pertussis infection, improving vaccination coverage to ensure herd immunity and uniformly establishing coverage throughout the country are essential. Furthermore, revaccination with acellular vaccine for schoolchildren as well as for the households of pregnant women is recommended. J. Clin. Lab. Anal. 21:154,161, 2007. © 2007 Wiley-Liss, Inc. [source] Community violence exposure and delinquent behaviors among youth: The moderating role of copingJOURNAL OF COMMUNITY PSYCHOLOGY, Issue 5 2003Margaret Rosario This study examines the moderating roles of guardian and peer support and behavioral coping strategies on the relations between youths' community violence exposure and their delinquent behavior. A sample of 667 public school sixth-graders in a large inner-city school district, and their parents or guardians, were interviewed to assess youths' recent exposure to community violence, their delinquent behavior, and proposed moderating variables. Support from guardians buffered the relation between girls' victimization by community violence and delinquency. Support from peers buffered the effects of witnessing community violence on delinquent behavior of boys, but it amplified the effects of victimization for both girls and boys. Avoidant coping behavior buffered the effect of victimization on delinquency for boys but unexpectedly amplified the effect of witnessing violence on delinquency for girls. For both genders, confrontational coping strategies amplified the impact of victimization on delinquency and, for boys only, amplified the impact of witnessing violence as well. Controls were imposed for variables expected to influence the relation between exposure and delinquency, such as ethnicity, family violence, delinquent behavior of friends, and recruitment cohort. Suggestions for future research and implications for intervention are discussed. © 2003 Wiley Periodicals, Inc. J Comm Psychol 31: 489,512, 2003. [source] Cancer risks in thiazolidinedione users compared to other anti-diabetic agents,PHARMACOEPIDEMIOLOGY AND DRUG SAFETY, Issue 5 2007Carol Koro PhD Abstract Purpose We conducted three nested case-control studies to evaluate the risk of breast, colon, and prostate cancers developing in patients exposed to thiazolidinediones (TZDs) compared with other anti-diabetic agents. Methods Cancer cases were matched to five controls by age, gender, calendar year, and time in the database from a cohort of 1,26,971 diabetic patients taking anti-diabetic medication in the US Integrated Healthcare Information Services database. Five hundred thirteen breast cancer cases were matched with 2557 controls, 408 cases of colon cancer were matched with 2027 controls and 643 cases of prostate cancer were matched with 3176 controls. Exposure to an anti-diabetic agent within 90 days preceding the index date was defined as recent exposure and at any time during the follow-up was defined as ever exposed. Results The adjusted odds ratios and 95%CI of cancer from ever exposure to TZDs compared to oral monotherapy, oral dual therapy, oral triple therapy, insulin monotherapy, insulin and oral therapy and all non-TZD anti-diabetic agents were, respectively for breast cancer: 0.91 (0.69,1.20), 0.80 (0.56,1.14), 0.87 (0.32,2.35), 1.27 (0.61,2.67), 0.71 (0.36,1.37), 0.89 (0.68,1.15); for colon cancer: 1.06 (0.80,1.40), 1.12 (0.77,1.63), 1.73 (0.39,7.78), 4.46 (1.05,19.00), 1.06 (0.50,2.26) 1.03 (0.80,1.32) and for prostate cancer: 1.08 (0.85,1.37), 0.89 (0.66,1.21); 0.82 (0.33,2.06); 1.80 (0.79,4.07), 1.10 (0.55,2.18), 1.04 (0.83,1.31). Results for exposure within 90 days of the date of the cancer were similar. Conclusions Our findings suggest that the effect of TZDs on the likelihood of development of the cancers studied (colon, prostate and breast) appears to be neutral and do not support a beneficial or deleterious effect of TZD on the cancers studied. Copyright © 2006 John Wiley & Sons, Ltd. [source] Neuromotor effects of short-term and long-term exposures to trichloroethylene in workers,AMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 9 2010Katsuyuki Murata MD Abstract Background Health effects of long-term exposure to organic solvents at low levels are a major concern in industrialized countries. To assess the neuromotor impact of trichloroethylene objectively, static postural sway and hand tremor parameters, along with urinary trichloroethanol (TCOH) and trichloroacetic acid (TCAA) levels, were investigated in 57 workers without obvious neurological disorders and 60 control subjects. Methods The workers had been occupationally exposed to trichloroethylene for 0.1,37 years. The cumulative exposure index (CEI) was calculated from their occupational history and total trichloro-compounds (TCOH,+,TCAA). Results Median levels in the workers were 1.7,mg/L for TCOH and 2.5,mg/L for TCAA, and the maximum ambient trichloroethylene concentration was estimated to be <22,ppm from the previously reported equation using TCOH,+,TCAA. Sway parameters with eyes open and tremor intensity in dominant hand were significantly larger in the exposed workers than in the control subjects when adjusting for possible confounders. A significant dose,effect association was seen between two sway parameters and urinary TCOH level in the workers. Tremor intensities in non-dominant hand differed significantly among three groups of the workers divided according to the CEI. Conclusions These findings suggest that trichloroethylene exposure, even at low levels of less than the short-term exposure limit by the ACGIH, can affect the neuromotor function of workers. The postural instability appears to result from recent exposure, and the increased tremor may occur due to short-term and long-term exposures. Hereafter, such objective measures, along with subjective symptoms, should be carefully used for the occupational exposure limit setting. Am. J. Ind. Med. 53:915,921, 2010. © 2010 Wiley-Liss, Inc. [source] Urinary 1-hydroxypyrene concentrations in Chinese coke oven workers relative to job category, respirator usage, and cigarette smokingAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 9 2007Bo Chen PhD Abstract Background 1-Hydroxypyrene (1-OHP) is a biomarker of recent exposure to polycyclic aromatic hydrocarbons (PAHs). We investigated whether urinary 1-OHP concentrations in Chinese coke oven workers (COWs) are modulated by job category, respirator usage, and cigarette smoking. Methods The present cross-sectional study measured urinary 1-OHP concentrations in 197 COWs from Coking plant I and 250 COWs from Coking plant II, as well as 220 unexposed referents from Control plant I and 56 referents from Control plant II. Results Urinary 1-OHP concentrations (geometric mean, µmol/mol creatinine) were 5.18 and 4.21 in workers from Coking plants I and II, respectively. The highest 1-OHP levels in urine were found among topside workers including lidmen, tar chasers, and whistlers. Benchmen had higher 1-OHP levels than other workers at the sideoven. Above 75% of the COWs exceeded the recommended occupational exposure limit of 2.3 µmol/mol creatinine. Respirator usage and increased body mass index (BMI) slightly reduced 1-OHP levels in COWs (P,<,0.1). Cigarette smoking significantly increased urinary 1-OHP levels in unexposed referents (P,<,0.005), but had no effect in COWs (P,>,0.1). Conclusions Chinese COWs, especially topside workers and benchmen, are exposed to high levels of PAHs. Urinary 1-OHP concentrations appear to be modulated by respirator usage and BMI in COWs, as well as by smoking in unexposed referents. Am. J. Ind. Med. 50:657,663, 2007. © 2007 Wiley-Liss, Inc. [source] The relationship between breast density and bone mineral density in postmenopausal womenCANCER, Issue 9 2004Diana S. M. Buist Ph.D., M.P.H. Abstract BACKGROUND It is not well understood whether breast density is a marker of cumulative exposure to estrogen or a marker of recent exposure to estrogen. The authors examined the relationship between bone mineral density (BMD; a marker of lifetime estrogen exposure) and breast density. METHODS The authors conducted a cross-sectional analysis among 1800 postmenopausal women , 54 years. BMD data were taken from two population-based studies conducted in 1992,1993 (n = 1055) and in 1998,1999 (n = 753). The authors linked BMD data with breast density information collected as part of a mammography screening program. They used linear regression to evaluate the density relationship, adjusted for age, hormone therapy use, body mass index (BMI), and reproductive covariates. RESULTS There was a small but significant negative association between BMD and breast density. The negative correlation between density measures was not explained by hormone therapy or age, and BMI was the only covariate that notably influenced the relationship. Stratification by BMI only revealed the negative correlation between bone and breast densities in women with normal BMI. There was no relationship in overweight or obese women. The same relationship was seen for all women who had never used hormone therapy, but it was not significant once stratified by BMI. CONCLUSIONS BMD and breast density were not positively associated although both are independently associated with estrogen exposure. It is likely that unique organ responses obscure the relationship between the two as indicators of cumulative estrogen exposure. Cancer 2004. © 2004 American Cancer Society. [source] Linear alkylbenzenes in muscle tissues of white croaker near a large ocean outfall in southern California, USAENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 2 2001Charles R. Phillips Abstract Muscle tissues of a bottom-dwelling marine fish, white croaker (Genyonemus lineatus), collected near a large wastewater outfall in southern California, USA, were analyzed for long-chain linear alkylbenzenes (LABs). Total LABs (summed concentrations of C11 through C14 isomers) were highest (166,748 ng g,1 wet wt) in individuals collected in the immediate vicinity of the Orange County Sanitation District (OCSD; Fountain Valley, CA, USA) outfall diffuser, whereas relatively lower concentrations occurred in fish from mid-shelf and inshore locations at distances of 2.5 and 5 km, respectively, from the outfall. Fish tissue LAB concentrations were roughly proportional to sediment LAB concentrations at the respective collection sites. The extent of LAB degradation, as determined by ratios of internal to external C12 isomers, did not appear to relate to LAB concentrations or sampling location. Tissue DDT and PCB concentrations were not significantly correlated with LABs and, thus, did not appear to relate to recent exposures to sewage residues from the OCSD discharge. Measurements of LAB concentrations in fish tissues may be widely applicable as a monitoring tool for interpreting exposures to sewage discharges. [source] Agreement between patient self-report and a Veterans Affairs national pharmacy database for identifying recent exposures to antibioticsPHARMACOEPIDEMIOLOGY AND DRUG SAFETY, Issue 1 2003Joshua P. Metlay MD Abstract Purpose The dramatic rise in antibiotic drug resistance among community pathogens has stimulated interest in the epidemiological relationship between antibiotic exposure and drug resistance. In assessing the strength of this relationship, studies are hampered by the lack of data on the accuracy of subject self-report of antibiotic exposure. The authors compared self-report with pharmacy dispensing data to determine the accuracy of self-reported antibiotic exposure. Methods The study design was a cross-sectional survey of veterans seen at the Philadelphia Veterans Affairs (VA) Medical Center in 1999 and 2000. Subjects reported exposures to antibiotics, antihypertensive drugs and nonsteroidal anti-inflammatory drugs through a structured telephone interview. The instrument included open-ended questions, condition-specific prompts and drug-specific prompts. Subject responses were linked to a national VA pharmacy database that served as the reference standard for evaluating self-reported exposures. Results The authors found that the sensitivity of self-report of antibiotic exposure increased with increasing use of prompts. A comprehensive assessment of antibiotic exposure identified 73% of antibiotic exposures, compared to 73% of antihypertensive drug exposures and 92% of nonsteroidal anti-inflammatory drug exposures. Conclusions Assessment of antibiotic exposure appears to be comparable to assessment of other chronic and episodic drugs. Multistep assessment of exposure improves the sensitivity of assessment. Copyright © 2002 John Wiley & Sons, Ltd. [source] Silicosis mortality among young adults in the United States, 1968,2004,,AMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 8 2008Jacek M. Mazurek MD Abstract Background To describe silicosis deaths in young (aged 15,44) adults in the U.S. during 1968,2004. Methods We analyzed the National Center for Health Statistics multiple cause-of-death records. Results Compared with silicosis decedents aged ,45 years (n,=,15,643), young decedents (n,=,237) were more likely to have silicosis listed as the underlying cause of death (74.3% vs. 48.2%, P,<,0.001), to be female (9.3% vs. 2.2%, P,<,0.001) and black (37.1% vs. 11.7%, P,<,0.001). Twenty-nine young silicosis decedents had industry and occupation information available. Occupations in construction and manufacturing industries were associated with significantly elevated proportionate mortality ratios for young silicosis deaths. Conclusions Silicosis deaths occur among young adults. Because these deaths are likely to reflect more intense and recent exposures, the follow-back investigations into the work sites where these individuals were exposed to silica should be conducted. Am. J. Ind. Med. 51:568,578, 2008. Published 2008 Wiley-Liss, Inc. [source] | |||||||||||||