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91.
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Sleep and Biological Rhythms - Sleep disorders are linked to obesity, type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD). The evidence suggests that dietary carbohydrate content may...  相似文献   
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Microbial structuring of marine ecosystems   总被引:6,自引:0,他引:6  
Despite the impressive advances that have been made in assessing the diversity of marine microorganisms, the mechanisms that underlie the participation of microorganisms in marine food webs and biogeochemical cycles are poorly understood. Here, we stress the need to examine the biochemical interactions of microorganisms with ocean systems at the nanometre to millimetre scale--a scale that is relevant to microbial activities. The local impact of microorganisms on biogeochemical cycles must then be scaled up to make useful predictions of how marine ecosystems in the whole ocean might respond to global change. This approach to microbial oceanography is not only helpful, but is in fact indispensable.  相似文献   
95.
Data on the effect of combined genetic polymorphisms, involved in folate metabolism, on the concentration of serum folate after folic acid supplementation are scarce. Therefore, we investigated the impact of seven gene polymorphisms on the concentration of serum folate and p-tHcy in healthy subjects after short-term folic acid supplementation. In a randomized, double blind, crossover study, apparently healthy subjects were given either 0.8 mg folic acid per day (n = 46) or placebo (n = 45) for 14 days. The washout period was 14 days. Fasting blood samples were collected on day 1, 15, 30 and 45. Data on subjects on folic acid supplementation (n = 91) and on placebo (n = 45) were used for the statistical analysis. The concentration of serum folate increased higher in subjects with higher age (53.5 ± 7.0 years) than in subjects with lower age (24.3 ± 3.2 years) after folic acid supplementation (p = 0.006). The baseline concentration of serum folate in subjects with polymorphism combination, reduced folate carrier protein, RFC1-80 GA and methylenetetrahydrofolate reductase, MTHFR677 CT+TT, was lower than RFC1-80 AA and MTHFR677 CT+TT (p = 0.002). After folic acid supplementation, a higher increase in the concentration of serum folate was detected in subjects with polymorphism combination RFC1-80 GA and MTHFR677 CC than RFC1-80 GG and MTHFR CT+TT combination (p < 0.0001). The baseline concentration of plasma total homocysteine (p-tHcy) was altered by combined polymorphisms in genes associated with folate metabolism. After folic acid supplementation, in subjects with combined polymorphisms in methylenetetrahydrofolate dehydrogenase, MTHFD1-1958 and MTHFR-677 genes, the concentration of p-tHcy was changed (p = 0.002). The combination of RFC1-80 and MTHFR-677 polymorphisms had a profound affect on the concentration of serum folate in healthy subjects before and after folic acid supplementation.  相似文献   
96.
The occurrence of accidents in petrochemical industries that cause environmental catastrophes has persuaded experts to use risk-oriented approaches. The approach is to rank the key elements of risk assessment by which the priority of each risk is specified compared to the other ones. The present study was performed to test the applicability of a multi-criteria decision-making approach for prioritizing environmental risks of a petrochemical complex in southwestern Iran. Accordingly, all risky activities of the Sodium Carbonate Production Unit (SCPU) were identified initially. Afterward, the relevant environmental components affected by the risky activities were specified. According to the specification, the most significant risks were shortlisted using experts’ judgment based on three criteria: “impact intensity,” “occurrence probability,” and the “extent of contamination dispersion in the environment.” The shortlisted environmental risks were then prioritized by the Method “Elimination et Choice Translating Reality (Elimination and Choice Expressing Reality)” abbreviated as ELECTRE. Based on the obtained results, “decreased air quality” and “manpower health threatening” are the top-priority risks while “poor quality of groundwater” was identified as the least priority risk. In a general conclusion, a multi-criteria decision-making approach is quite useful for assessing environmental risks of petrochemical industries.  相似文献   
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A series of 1,2,4-triazole derivatives containing thiosemicarbazone linkage was synthesized and evaluated for their in vitro antiamoebic activity against HM1:IMSS strain of Entamoeba histolytica. All the compounds were capable of inhibiting the growth of E. histolytica out of which four compounds (IC(50)=0.28-1.38 μM) were found to have better efficacy than the standard drug Metronidazole (IC(50)=1.8 μM). Cytotoxicity of the active compounds was assessed by MTT assay using human breast cancer MCF-7 cell line, which revealed that all the compounds were low cytotoxic in the concentration range of 2.5-250 μM.  相似文献   
99.
The 32-base pair deletion on the C–C chemokine receptor 5 gene (CCR5-delta32) is known as a protective allele against immune system disorders. We have studied this variation in Iranian multiple sclerosis (MS) patients and healthy controls. DNA samples were prepared from the whole blood of 254 patients with MS and 380 healthy controls. We amplified the fragment including the CCR5-delta32 polymorphism and visualized the products in a documentation system after agarose gel electrophoresis. Data were analysed using one-way ANOVA and Fisher’s exact tests with SPSS-v13 and STATA-v8 software. The delta32 allele was more frequent in MS patients when compared with controls (OR = 2.3, P < 0.0001). Also, we found a significant difference in the frequency of the delta32/delta32 genotype among patients and controls (OR = 7.4, P < 0.001). The mean age at onset and progression index was not significantly different between patients with various genotypes. According to our study, the delta32 allele of the CCR5 gene might be a predisposing factor for MS development in the Iranian population. However, there were no associations between this polymorphism and the clinical course of the disease in this study.  相似文献   
100.

Background

The coral holobiont includes the coral animal, algal symbionts, and associated microbial community. These microbes help maintain the holobiont homeostasis; thus, sustaining robust mutualistic microbial communities is a fundamental part of long-term coral reef survival. Coastal pollution is one major threat to reefs, and intensive fish farming is a rapidly growing source of this pollution.

Methodology & Principal Findings

We investigated the susceptibility and resilience of the bacterial communities associated with a common reef-building coral, Porites cylindrica, to coastal pollution by performing a clonally replicated transplantation experiment in Bolinao, Philippines adjacent to intensive fish farming. Ten fragments from each of four colonies (total of 40 fragments) were followed for 22 days across five sites: a well-flushed reference site (the original fragment source); two sites with low exposure to milkfish (Chanos chanos) aquaculture effluent; and two sites with high exposure. Elevated levels of dissolved organic carbon (DOC), chlorophyll a, total heterotrophic and autotrophic bacteria abundance, virus like particle (VLP) abundances, and culturable Vibrio abundance characterized the high effluent sites. Based on 16S rRNA clone libraries and denaturing gradient gel electrophoresis (DGGE) analysis, we observed rapid, dramatic changes in the coral-associated bacterial communities within five days of high effluent exposure. The community composition on fragments at these high effluent sites shifted towards known human and coral pathogens (i.e. Arcobacter, Fusobacterium, and Desulfovibrio) without the host corals showing signs of disease. The communities shifted back towards their original composition by day 22 without reduction in effluent levels.

Significance

This study reveals fish farms as a likely source of pathogens with the potential to proliferate on corals and an unexpected short-term resilience of coral-associated bacterial communities to eutrophication pressure. These data highlight a need for improved aquaculture practices that can achieve both sustainable industry goals and long-term coral reef survival.  相似文献   
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