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81.

Background

Despite growing attention to nutrition and quality of life in cardiovascular disease survivors, the impact of dietary factors according to disease type or to quality of life domain is poorly understood. We investigated the effects of B vitamin and/or n-3 fatty acid supplementation on health-related quality of life among survivors of stroke, myocardial infarction, or unstable angina.

Methods

We performed ancillary analyses of the SU.FOL.OM3 trial (2003–2009; France). In total, 2,501 men (mean age = 61 y) and women (mean age = 63 y) were randomized in a 2×2 factorial design to: 1) 0.56 mg 5-methyl-tetrahydrofolate, 3 mg vitamin B6, 0.02 mg vitamin B12; 2) 600 mg eicosapentaenoic and docosahexaenoic acids in a 2∶1 ratio; 3) B vitamins and n-3 fatty acids combined; or 4) placebo. Health-related quality of life was evaluated at follow-up with the Medical Outcomes Study 36-Item Short Form Health Survey. Data from 2,029 individuals were used in this analysis.

Results

After 3.1±0.4 y, no effects of supplementation with either B vitamins or n-3 fatty acids on quality of life (physical or mental health domains) were found. However, participants receiving B vitamins had slightly more activity limitations due to emotional problems compared with those not receiving B vitamins (mean difference = 3.8; 95% CI: 0.4, 7.1). A significant interaction of treatment by prior disease revealed an inverse association between n-3 fatty acids and vitality among myocardial infarction survivors (mean difference = 2.9; 95% CI: 0.5, 5.2).

Conclusions

There were no beneficial effects of supplementation with relatively low doses of B vitamins or n-3 fatty acids on health-related quality of life in cardiovascular disease survivors. The adverse effects of B vitamins on activity limitations and of n-3 fatty acids on vitality among individuals with prior myocardial infarction merit confirmation.  相似文献   
82.
Inasmuch as the neurohormone melatonin is synthetically derived from serotonin (5-HT), a close interrelationship between both has long been suspected. The present study reveals a hitherto unrecognized cross-talk mediated via physical association of melatonin MT2 and 5-HT2C receptors into functional heteromers. This is of particular interest in light of the “synergistic” melatonin agonist/5-HT2C antagonist profile of the novel antidepressant agomelatine. A suite of co-immunoprecipitation, bioluminescence resonance energy transfer, and pharmacological techniques was exploited to demonstrate formation of functional MT2 and 5-HT2C receptor heteromers both in transfected cells and in human cortex and hippocampus. MT2/5-HT2C heteromers amplified the 5-HT-mediated Gq/phospholipase C response and triggered melatonin-induced unidirectional transactivation of the 5-HT2C protomer of MT2/5-HT2C heteromers. Pharmacological studies revealed distinct functional properties for agomelatine, which shows “biased signaling.” These observations demonstrate the existence of functionally unique MT2/5-HT2C heteromers and suggest that the antidepressant agomelatine has a distinctive profile at these sites potentially involved in its therapeutic effects on major depression and generalized anxiety disorder. Finally, MT2/5-HT2C heteromers provide a new strategy for the discovery of novel agents for the treatment of psychiatric disorders.  相似文献   
83.
84.
Protein kinases and phosphatases play crucial roles in all the major cellular processes, such as signal transduction, cell differentiation, cell proliferation and cell cycle progression. Protein phosphorylation or dephosphorylation can form the basis of many critical processes, including enzyme activation or inactivation, protein localization and protein degradation. Given the importance of protein kinases to cellular development and function, it is critical that there are effective ways of disseminating information on protein kinases to the research community. This review describes such a web resource, 'The Protein Kinase Resource' (http://pkr.sdsc.edu/html/index.shtml), which serves as a repository for cellular and molecular data on protein kinases.  相似文献   
85.
Expressed sequence tag projects have currently produced over 400 000 partial gene sequences from more than 30 nematode species and the full genomic sequences of selected nematodes are being determined. In addition, functional analyses in the model nematode Caenorhabditis elegans have addressed the role of almost all genes predicted by the genome sequence. This recent explosion in the amount of available nematode DNA sequences, coupled with new gene function data, provides an unprecedented opportunity to identify pre-validated drug targets through efficient mining of nematode genomic databases. This article describes the various information sources available and strategies that can expedite this process.  相似文献   
86.
Soybean lipoxygenase-1 (LOX-1) is used widely as a model for studying the structural and functional properties of the homologous family of lipoxygenases. The crystallographic structure revealed that LOX-1 is organized in a beta-sheet N-terminal domain and a larger, mostly helical, C-terminal domain. Here, we describe the overall structural characterization of native unliganded LOX-1 in solution, using small angle X-ray scattering (SAXS). We show that the scattering pattern of the unliganded enzyme in solution does not display any significant difference compared with that calculated from the crystal structure, and that models of the overall shape of the protein calculated ab initio from the SAXS pattern provide a close envelope to the crystal structure. These data, demonstrating that LOX-1 has a compact structure also in solution, rule out any major motional flexibility of the LOX-1 molecule in aqueous solutions. In addition we show that eicosatetraynoic acid, an irreversible inhibitor of lipoxygenase used to mimic the effect of substrate binding, does not alter the overall conformation of LOX-1 nor its ability to bind to membranes. In contrast, the addition of glycerol (to 5%, v/v) causes an increase in the binding of the enzyme to membranes without altering its catalytic efficiency towards linoleic acid nor its SAXS pattern, suggesting that the global conformation of the enzyme is unaffected. Therefore, the compact structure determined in the crystal appears to be essentially preserved in these various solution conditions. During the preparation of this article, a paper by M. Hammel and co-workers showed instead a sharp difference between crystal and solution conformations of rabbit 15-LOX-1. The possible cause of this difference might be the presence of oligomers in the rabbit lipoxygenase preparations.  相似文献   
87.
To establish a system for genetically engineered cell fate mapping, different vectors carrying the Lc gene, a member of the R gene family, were delivered into embryonic and meristematic cells of maize by the microinjection technique. Vectors in which the Lc cDNA is driven either by a constitutive promoter (CaMV 35S), with or without the Adh1 intron 1 of maize, or a tissue-specific promoter (phosphoenolpyruvate carboxylase, PEPC) as well as self-replicating wheat dwarf virus (WDV) vectors carrying a Lc-expression-cassette, have been tested. The ability of these vectors to transactivate was evaluated in mesophyll-derived protoplasts of the maize genotype appropriate for these microinjection experiments. The expression product of the introduced Lc gene can substitute for mutated R and B loci, resulting in anthocyanin production. Analogous results were obtained by microinjection into organized tissues, where transactivation of anthocyanin biosynthesis resulted in pigmented sectors in somatic embryos (B79) and in the leaves of plants regenerated from the cultivated shoot apical meristems (K55, r-g, b). The tissue-specific appearance of pigmented sectors in leaves, using the mesophyll-specific PEPC promoter suggests the possibility of using this approach for layer-specific cell fate studies. The presence of the introduced plasmids in leaves showing red sectors 20–30 days after injection was proven by PCR analysis.  相似文献   
88.
89.
Candida lipolytica has rarely been reported as a human pathogen. We observed two cases of fungemia caused by C. lipolytica, one of them in a 12-year-old child with cystic pancreatic fibrosis in advanced phase and another in a 86-year-old woman who presented vesical neoformation with peritoneal fibrosis, bilateral hydronephrosis and recurrent urinary tract infections. After antifungal treatment and catheter removal, the fungemia appeared to be finished and blood cultures were negative.  相似文献   
90.

Background  

Lichtheimia corymbifera (previously Absidia corymbifera) is a filamentous zygomycetes belonging to the order Mucorales and to the family Lichtheimiaceae. Members of genus Lichtheimia spp. are cosmopolitan and ubiquitous in nature. Lichtheimia corymbifera is a recognized agent of diseases in man and animals. In cattle it causes abortion and mastitis. Three cases of bovine abortion occurred in a herd located in the Po Valley. Serological examinations were performed on fetal and mother's blood. One of the aborted fetus was referred to our laboratory. The paper describes the isolation and characterization of Lichtheimia corymbifera from a bovine aborted fetus.  相似文献   
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