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101.
The intensive use of antibiotics in human and veterinary medicine, associated with mechanisms of bacterial genetic transfer, caused a selective pressure that contributed to the dissemination of antimicrobial resistance in different bacteria groups and throughout different ecosystems. Iberian wolf, due to his predatory and wild nature, may serve as an important indicator of environmental contamination with antimicrobial resistant bacteria. The aim of this study was to characterize the diversity of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli isolates within the fecal microbiota of Iberian wolf. Additionally, the identification of other associated resistance genes, phylogenetic groups, and the detection of virulence determinants were also focused on in this study. From 2008 to 2009, 237 fecal samples from Iberian wolf were collected in Portugal. E. coli isolates with TEM-52, SHV-12, CTX-M-1, and CTX-M-14-type ESBLs were detected in 13 of these samples (5.5%). This study reveals the presence of ESBL-producing E. coli isolates, in a wild ecosystem, which could be disseminated through the environment. Moreover, the presence of resistant genes in integrons and the existence of virulence determinants were shown. The association between antibiotic resistance and virulence determinants should be monitored, as it constitutes a serious public health problem.  相似文献   
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This study investigated the chemical composition (by using gas chromatography/flame ionization detection and gas chromatography/mass spectrometry, an antioxidant [1,1-diphenyl-2-picrylhydrazyl] [DPPH] radical-scavenging assay, and a 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonate [ABTS] radical cation-scavenging assay) and the antimalarial and cytotoxic activities of essential oil extracted from leaves of Melaleuca armillaris. Thirty-two components representing more than 98% of the total composition of the essential oil were identified. The main components were 1,8-cineole (85.8%), camphene (5.05%), and α-pinene (1.95%). The antioxidant activity by ABTS assay showed a mean (± standard deviation) 50% inhibitory concentration (IC(50)) value of 247.3 ± 3.9 mg/L, and the DPPH assay yielded an IC(50) value of 2183.6 ± 44.3 mg/L. The antimalarial study indicated that the essential oil had mild activity against the chloroquine-resistant Plasmodium falciparum FcB1 strain (IC(50), 27 ± 2 mg/L). The cytotoxic activity of this essential oil was tested against MCF7 human breast cancer cells and was found to be high (IC(50), 12 ± 1 mg/L).  相似文献   
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Cutaneous and visceral leishmaniasis (VL, CL) represent the most frequent vector-borne diseases in Tunisia. Their biological confirmation is necessary before the administration of restricting, expensive and toxic specific treatments. Retrospective evaluation of the contribution of Leishmania cultures on NNN medium in leishmaniasis diagnosis have been done using the data of 375 cultures concerning 214 CL cases and 125 VL cases consecutively recruited in Pasteur Institute of Tunisia between 1995 and 2007. The global sensitivity of the culture in the course of CL was of 68.2%. It was significantly higher during zoonotic CL (78.8%) compared to that during sporadic CL (54.9%); p<0.001. This difference is explained by the easier thrust in NNN medium of Leishmania (L.) major, the agent of zoonotic CL than that of L. infantum, particularly its zymodeme MON-24, agent of sporadic CL. In the course of VL, and in spite of the better sensitivity of bone marrow aspirates (BMA) culture (70.8%), the blood buffy-coat, which permit to avoid the trauma induced by BM aspiration gave promising results (58.2%), the difference being not significant. Besides, in the course of both CL and VL, the direct examination of smears is revealed more sensitive, respectively 89.7% and 93.4% (p<0.01 and p<0.01). Although, systematic cultures practise, in parallel with direct examination, is recommended. In fact, in addition of straightening out some diagnosis, 22 cases in our series, the culture provide the isolation and the isoenzymatic identification of the causative species and strains allowing a better comprehend of parasite life cycles and a disposing of important epidemiological data for suitable control measures. As known with all cultures, those of Leishmania are also exposed to the contamination problem, which reached 5.9% in our study. In conformity with previsions, the contamination concerned much more cutaneous samples (8.4%) than blood or BM ones (2.5%; p=0.015).  相似文献   
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The association between nuts intake and cognitive function is inconclusive. We aimed to investigate the association between habitual nuts consumption and cognition among Qatari adults. Data from 1000 participants aged >20 years who attended Qatar Biobank (QBB) were used. Nuts consumption was assessed by a food frequency questionnaire (FFQ). Blood samples were measured for magnesium, lipids and glucose. Mean reaction time (MRT) was used as an indicator of cognitive function. Linear regression was used to assess the association. A total of 21.1% of the participants reported consuming nuts ≥4–6 times/week (high consumption) while 40.2% reported consuming ≤1 time/month (low consumption). The mean MRT was 715.6 milliseconds (SD 204.1). An inverse association was found between nuts consumption and MRT. Compared to those with a low consumption, high consumption of nuts had a regression coefficient of −36.9 (95% CI −68.1 to −5.8) after adjusting for sociodemographic and lifestyle factors. The inverse association between nuts and MRT was mainly seen among those >50 years. There was an interaction between nuts consumption and hypertension. The association between nuts consumption and MRT was not mediated by hypertension, diabetes, or serum magnesium. Habitual higher consumption of nuts is positively associated with cognitive function, especially among old adults.  相似文献   
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