The goal of this study was to investigate the involvement of a tropical Indian estuary in the emergence of antibiotic resistance genes (ARGs)-harboring hypervirulent E. coli of global significance. A total of 300 E. coli isolates was tested for antibiotic susceptibility to β-lactams, aminoglycosides, chloramphenicol, quinolones, sulphonamides, tetracyclines, and trimethoprim. The E. coli isolates were screened for the presence of antibiotic resistance genes (blaTEM, blaCTX-M, tetA, tetB, sul1, sul2, strA, aphA2, catI, dhfr1, and dhfr7), integrase (int1, int2, and int3), Shiga toxin genes (stx1 and stx2) and extraintestinal virulence genes (papAH, papC, sfa/focDE, kpsMT II, and iutA). The highest prevalence of antibiotic resistance was observed for ampicillin, followed by tetracycline, and nalidixic acid. Among E. coli isolates, 64% were resistant to at least one of the 15 antibiotics tested, and approximately 40% were multiple antibiotic-resistant (MAR). More than 40% (n?=?122) of E. coli isolates had ARGs. Integrase 1 (int1) was found in 7.6% of E. coli isolates. Among E. coli isolates, 16.3% (n?=?49) were extraintestinal pathogenic E. coli (ExPEC), and approximately 34.6% (n?=?17) of ExPEC had ARGs. A hypervirulent ARGs-harboring STEC was isolated. The prevalence of Shiga toxin-producing E. coli (STEC) was low (n?=?1). The prevalence of ARGs-harboring pathogenic E. coli isolates was higher in stations close to the City (urban area), than that of other stations. ERIC-PCR (enterobacterial repetitive intergenic consensus sequence polymerase chain reaction) analysis revealed a high degree of genetic diversity among the ARGs-harboring E. coli isolates. The results demonstrate a high prevalence of ARGs-harboring E. coli in estuarine water and confirm the need for a better wastewater treatment facility and proper control measures to reduce the discharge of sewage and wastewater into the aquatic environments. 相似文献
Our study investigates the relative contribution of genetic and environmental factors to the timing of food timing and related behaviors. Our results show that the heritability of the midpoint of intake, the midpoint between breakfast and dinner, was 64%. In addition, trait heritability was higher for breakfast than lunch, whereas no heritability was detected for dinner. These results suggest that interventions related to food timing may be more effective when targeting afternoon/evening behaviors, such as lunch or dinner times.
Problem Individual differences in susceptibility to trichloroethylene-induced nephrocarcinogenicity may be conferred by genetic polymorphisms
of glutathione S-transferases (GST), because enzymes of this group are pivotal for the metabolic activation of trichloroethylene. Because
of a potential involvement of N-acetylation in the detoxication of reactive trichloroethylene metabolite(s) to N-acetyl-cysteine derivatives, polymorphisms of the NAT2 gene may also be relevant.
Methods The primary collective used for a re-investigation of these questions was that of a hospital-based case-control study by Brüning
et al. (Am J Ind Med 43:274–285, 2003) of 134 renal cell cancer cases (20 cases exposed to trichloroethylene) and 401 matched controls. Genetic polymorphisms of
GSTT1, GSTM1, GSTP1 and NAT2 were studied. Additional control collectives of non-diseased persons were used for comparison of allele frequencies.
Results No genetic influences on the development of renal cancer due to trichloroethylene were apparent, related to the deletion polymorphisms
of GSTT1 and GSTM1, as well as to the NAT2 rapid/slow acetylator states. However, renal cell cancer cases displayed a somewhat higher proportion of the homozygous GSTP1313A wild type (GSTP1*A), although this was not statistically significant (χ2 test: P = 0.1071, when using only the original controls of Brüning et al. (2003); P = 0.0781 with inclusion of the additional controls).
Conclusion The re-investigation does not confirm the working hypothesis of an influence of the deletion polymorphisms of the glutathione
S-transferases GSTT1 and GSTM1 on renal cell cancer development due to high occupational exposures to trichloroethylene. 相似文献
Summary Occupational epidemiology has its roots in classical medicine.
However, it became a quantitative discipline only in the 20th
century, through the pioneering work of individuals such as
Case, Lloyd, and Selikoff and organizations such as the Division
of Occupational Health of the U.S. Public Health Service. Studies
of chemical dye workers, bituminous coal miners, smelting
workers, and uranium miners have been especially important
sources of innovations in methodology and in development of
logical reasoning leading to acceptance of causal relationships
of occupational exposures that lead to respiratory diseases and
cancer. The cooperation of labor unions, such as those of steel
and asbestos workers, has often been a crucial factor in providing
essential data.
Zusammenfassung Fragen der Kausalität in der Geschichte der ArbeitsepidemiologieDie Arbeitsepidemiologie hat ihre Wurzeln in der klassischen
Medizin. Allerdings wurde sie erst im 20. Jahrhundert zu einer
quantitativen Wissenschaft. Dies dank der Pionierarbeiten von
Personen und Organisationen wie Case, Lloyd und Selikoff und
der "Division of Occupational Health" (Abteilung für Arbeitsschutz)
des "U.S. Public Health Service" (öffentliches Gesundheitswesen).
Studien mit Arbeitern in der chemischen Farbenindustrie,
in Bitumenkohleminen, Erzhütten und Uranminen
haben ganz besonders zu Neuerungen in methodischer Hinsicht,
aber auch zur Entwicklung einer logischen Beweisführung
beigetragen, was letztendlich zur Akzeptanz von
kausalen Zusammenhängen zwischen Umweltbelastungen am
Arbeitsplatz und dem Auftreten von Atemwegerkrankungen
und Krebs führte. Die Kooperation mit Gewerkschaften, wie jenen
der Stahl- und Asbestarbeiter, war für die Erfassung bedeutungsvoller
Daten oft ausschlaggebend.
Résumé Questions de causalité dans l'histoire de l'épidémiologie des
maladies professionnellesL'épidémiologie des maladies professionnelles plonge ses racines
dans la médecine classique. Cependant, elle n'est devenue
une discipline quantitative qu'au 20ème siècle, grâce au travail
de pionnier d'individus tels que Case, Lloyd et Selikoff, ainsi
que des organisations telle que la Division de Santé au Travail
du service américain de Santé Publique. Des études sur les ouvriers
de l'industrie chimique de la teinture, des mines de charbon,
des fonderies ou des mines d'uranium ont été des sources
particulièrement importantes d'innovation méthodologique et
de développement du raisonnement logique aboutissant ä l'acceptation
de relation causale entre des expositions professionnelles
et des maladies respiratoires ou le cancer. La collaboration
de syndicats professionnels, tels que ceux des ouvriers de
la sidérurgie ou travaillant avec l'amiante, a souvent été déterminante
pour l'obtention de données essentielles.
This study used prospective data to investigate the validity of a retrospective measure of suicide attempts from four different perspectives.
Methods
Data were retrieved from 883 participants in the Raising Healthy Children project, a longitudinal study of youth recruited from a Pacific Northwest school district. The retrospective measure was collected when participants were 18–19 years of age and results were compared with measures of depressive symptoms collected prospectively.
Results
Results showed strong corroboration between retrospective reports of first suicide attempt and prospective measures of depression, with attempters experiencing significantly more depression than their nonattempting peers, t (df = 853) = 10.26, p < .001. In addition, within the attempter group, depression scores during the year of their reported first attempt were significantly higher than the average depression score across previous years, t (df = 67) = 3.01, p < .01.
Conclusions
Results from this study suggest that the reports of older adolescents regarding their suicide attempts are corroborated by their prospective reports of depression in childhood and earlier adolescence. Thus, there is support that retrospective measures of suicidal behavior, namely suicide attempts, may be a valid method of assessment. 相似文献
The present study aimed to determine the antioxidant activity and phytochemical contents in 10 underutilized fruits of Andaman Islands (India) namely Malpighia glabra L., Mangifera andamanica L., Morinda citrifolia L., Syzygium aqueum (Burm.f) Alst., Annona squamosa L., Averrhoa carambola L., Averrhoa bilimbi L., Dillenia indica L., Annona muricata L. and Ficus racemosa L. The antioxidant activity varied from 74.27% to 98.77%, and the methanol extract of M. glabra showed the highest antioxidant activity (98.77%; inhibitory concentration, IC50 = 262.46 μg/ml). Methanol was found to be a better solvent than acetone and aqueous for estimating the antioxidant activity. M. glabra was found to be rich in phytochemicals viz. polyphenol (355.74 mg/100 g), anthocyanin (91.31 mg/100 g), carotenoids (109.16 mg/100 g), tannin (24.39 mg/100 g) and ascorbic acid (394.23 mg/100 g). Carbohydrate content was estimated to be highest in M. glabra (548 mg/100 g). Phenols, tannins, anthocyanins and carotenoids contents showed positive correlation (r2 = 0.846, r2 = 0.864, r2 = 0.915 and r2 = 0.806, respectively) with antioxidant activity. The information generated in present study will be useful for bioprospecting of underutilized fruits of Andaman Islands. 相似文献
Objective: The present study aims to investigate the neuroprotective effect of caffeine against aluminum chloride (AlCl3)-induced neurotoxicity in rats.Methods: Twenty-one male albino rats were divided into 3 groups: control, AlCl3-intoxicated group that received daily oral administration of AlCl3 (100?mg/kg for 30 days) and protected group injected daily with caffeine (20?mg/kg intraperitoneally) one hour before oral administration of AlCl3 for 30 days. Levels of lipid peroxidation, reduced glutathione, and nitric oxide and the activities of acetylcholinesterase (AchE) and Na+/K+-ATPase were measured spectrophotometrically. Tumor necrosis factor-α (TNF-α) was evaluated by ELISA kit.Results: The data revealed evidence of oxidative and nitrosative stress in the cerebral cortex, hippocampus, and striatum of AlCl3-intoxicated rats. This was indicated from the increased levels of lipid peroxidation and nitric oxide together with the decreased level of reduced glutathione. Moreover, the daily AlCl3 administration increased AchE and Na+/K+-ATPase activities and the level of TNF-α in the selected brain regions. Protection with caffeine ameliorated the oxidative stress induced by AlCl3 in the cerebral cortex, hippocampus, and striatum. In addition, caffeine restored the elevated level of TNF-α in the hippocampus and striatum. This was accompanied by an improvement in the activities of AchE and Na+/K+-ATPase in the studied brain regions.Discussion and conclusions: The present findings clearly indicate that caffeine provides a significant neuroprotection against AlCl3-induced neurotoxicity mediated by its antioxidant, anti-inflammatory, and anticholinesterase properties. 相似文献
