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An ecosystem approach to human health was adopted in a community-based study carried out in Bebnine, an underserved town in Lebanon. The objective of the study is to examine the association between women’s household practices and diarrhea among children in a setting where contaminated drinking water and intestinal diseases are common. A total of 280 women were randomly selected and interviewed using a structured questionnaire. Data were collected on 712 children between the ages of 6 and 14. The study instrument included determinants of diarrhea such as sociodemographic characteristics, water, sanitation, hygiene practices, gender variables, and behavioral risk factors. Multivariate regression analysis was employed to examine the association between water handling practices and diarrhea. The prevalence of diarrhea is 5%. Female children are more likely to suffer from diarrhea than male children (OR = 2.58; 95% CI: 1.19–5.62). Treatment of drinking water at the household level and the use of drinking water for cooking and the preparation of hot beverages are protective against diarrhea (OR = 0.15; 95% CI: 0.03–0.65). Female caretakers’ behaviors such as daily bathing and seeking medical care at times of illness are protective against diarrhea in children. The findings suggest that diarrhea is a gendered health problem. Female children, who are generally more involved in household activities than male children, are at higher risk of suffering from diarrhea. Female caretakers’ personal hygiene, household practices, and perceptions of diarrhea are additional risk factors. Intervention activities would be more effective if based on a better understanding of gender roles and household power relations.  相似文献   
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Molecular Biology Reports - Acinetobacter baumannii (A. baumannii) is among the important causes of nosocomial infections. Due to the emergence of antibiotic resistance, many problems have been...  相似文献   
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Laccases are enzymes of the family multicopper oxidases, being widely used for biotechnological applications (Canas & Camarero, 2010). The enzymes’ catalytic cycle consists of the oxidation of the substrate with the concomitant reduction of molecular oxygen to water. In this process, the substrate is converted to a free radical, that can oxidize larger substrates acting as a mediator or it can undergo polymerization. Substrate binding is not specific, and there is a large diversity of substrates for laccases. Moreover, the binding site shows important differences among diverse species. The goal of the present work is to characterize the laccase binding pocket of different species, in order to establish their common pharmacophoric characteristics. For this purpose, we have carried out docking studies with a subset of substrates, covering the diversity of substrates using the Glide program (Friesner et al., 2004). We have also analyzed the characteristics of the binding site using diverse probes. We further have rationalized the differential values of km found among diverse species for a specific substrate. Finally, special attention has been devoted to the binding of the mediator 2,2′-azido-di-(3-ethylbenzothiazoline)-6-sulfonic acid (ABTS), commonly used in industrial processes. Figure 1 shows, ABTS docked onto the fungal laccase, whereas Figure 2 shows ABTS docked onto the bacterial laccase. The analysis of the protein–ligand complex together with the corresponding optimized geometries of the possible substrate species carried out using DFT suggest that the bound species is the protonated form of ABTS as previously suggested (Enguita et al., 2004). Furthermore, the results of this study also suggest that its mechanism of oxidation occurs in a similar way to the rest of substrates/mediators, in contrast to previous suggestions (Fabbrini et al., 2002).   相似文献   
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Adoptive transfer of autologous dendritic cells (DCs) loaded with tumor-associated CD4 and CD8 T cell epitopes represents a promising avenue for the immunotherapy of cancer. In an effort to increase the loading of therapeutic synthetic peptides on MHC II molecules, we used a mutant of HLA-DM (DMY) devoid of its lysosomal sorting motif and that accumulates at the cell surface. Transfection of DMY into HLA-DR(+) cells resulted in increased loading of the exogenously supplied HA(307-318) peptide, as well as increased stimulation of HA-specific T cells. Also, on transduction in mouse and human DCs, DMY increased loading of HEL(48-61) and of the tumor Ag-derived gp100(174-190) peptides, respectively. Interestingly, expression of DMY at the surface of APCs favored Th1 differentiation over Th2. Finally, we found that DMY(-) and DMY(+) mouse APCs differentially stimulated T cell hybridomas sensitive to the fine conformation of peptide-MHC II complexes. Taken together, our results suggest that the overexpression of HLA-DMY at the plasma membrane of DCs may improve quantitatively, but also qualitatively, the presentation of CD4 T cell epitopes in cellular vaccine therapies for cancer.  相似文献   
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New material of the wasp family Maimetshidae (Apocrita) is presented from four Cretaceous amber deposits - the Neocomian of Lebanon, the Early Albian of Spain, the latest Albian/earliest Cenomanian of France, and the Campanian of Canada. The new record from Canadian Cretaceous amber extends the temporal and paleogeographical range of the family. New material from France is assignable to Guyotemaimetsha enigmatica Perrichot et al. including the first females for the species, while a series of males and females from Spain are described and figured as Iberomaimetsha Ortega-Blanco, Perrichot & Engel, gen. n., with the two new species Iberomaimetsha rasnitsyni Ortega-Blanco, Perrichot & Engel, sp. n. and Iberomaimetsha nihtmara Ortega-Blanco, Delclòs & Engel, sp. n.; a single female from Lebanon is described and figured as Ahiromaimetsha najlae Perrichot, Azar, Nel & Engel, gen. et sp. n., and a single male from Canada is described and figured as Ahstemiam cellula McKellar & Engel, gen. et sp. n. The taxa are compared with other maimetshids, a key to genera and species is given, and brief comments made on the family.  相似文献   
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3-Acetyl-11-keto-β-boswellic acid (AKBA), a pentacyclic triterpenic acid present in gum resin of Boswellia serrata, has been found to possess antioxidant and neuroprotective properties. In this study, we aimed to examine protective properties of AKBA against glutamate-induced neuronal injury. To investigate the effects of AKBA (2.5-10 µM) on glutamate injury in neuron-like cells PC12 and N2a, two treatment regimens (incubation for 2 or 0 hours before glutamate exposure) were used. Then, the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method was used to determine viability of the cells. Cellular redox status was evaluated using fluorimetry and comet assays. Annexin V/propidium iodide double staining and Western blot analysis of relative apoptotic proteins were conducted. Based on the results, 24 hours incubation with glutamate (8 mM) increased the cell mortality of PC12 and N2a (P < .001). However, AKBA (2.5-10 µM) enhanced the cell viability in both treatment regimens (P < .001). Also co- and pretreatment with AKBA significantly attenuated lipid peroxidation, reactive oxygen species production, and DNA injury (P < .05 and P < .001). AKBA also restored the activity of cellular superoxide dismutase under glutamate toxicity; this effect was seen to be more significant during the pretreatment regimen (P < .001). Moreover, Western blot analysis indicated that AKBA inhibited glutamate-induced programmed cell death through depressing the elevation of the expression ratio of Bax/Bcl-2 and cleaved-caspase-3 proteins, concentration-dependently. Overall, the present findings suggest the neuroprotective activities of AKBA against glutamate-induced cell injury probably by inhibiting oxidative damage and reducing apoptotic cell death.  相似文献   
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