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1.
Strains of Fusarium proliferatum, F. subglutinans, F. anthophilum, F. annulatum, F. succisae, F. beomiforme, F. dlamini, F. napiforme, and F. nygamai from a variety of substrates and geographic areas were tested for the production of fumonisin B1 in culture. None of the cultures of F. subglutinans (0 of 23), F. annulatum (0 of 1), F. succisae (0 of 2), or F. beomiforme (0 of 15) produced fumonisin B1 in culture. Strains of F. proliferatum (19 of 31; 61%) produced fumonisin B1 in amounts ranging from 155 to 2,936 ppm, strains of F. anthophilum (3 of 17; 18%) produced fumonisin B1 in amounts ranging from 58 to 613 ppm, strains of F. dlamini (5 of 9; 56%) produced fumonisin B1 in amounts ranging from 42 to 82 ppm, strains of F. napiforme (5 of 33; 15%) produced fumonisin B1 in amounts ranging from 16 to 479 ppm, and strains of F. nygamai (10 of 27; 37%) produced fumonisin B1 in amounts ranging from 17 to 7,162 ppm. Of the species tested, F. proliferatum is the most important producer of fumonisin B1 because of its association with corn and animal mycotoxicoses such as porcine pulmonary edema. F. napiforme and F. nygamai also may be important because of their association with the food grains millet and sorghum. At present, F. anthophilum and F. dlamini are of minor importance because they are not associated with corn or other major food grains and have only a limited geographic range. This is the first report of the production of fumonisins by F. anthophilum, F. dlamini, and F. napiforme.  相似文献   
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The purification of rabbit lutropin is described. A product with a potency of 1.53 X NIH-LH-Sl was obtained as assayed by the ovarian ascorbic acid depletion assay. In a homologous radioimmunoassay, which is described, rabbit lutropin has a potency 4.83 X NIH-LH-Sl. In a radioligand assay, utilizing labeled ovine lutropin as the trace, the relative potency was 0.47 X NIH-LH-Sl measured by 50% inhibition comparison since rabbit lutropin response in this system did not parallel ovine lutropin. A counter-current distribution procedure for separation of rabbit lutropin subunits is described. Amino acid composition of the isolated subunits and intact rabbit lutropin was determined. The carbohydrate composition of the latter is presented; only amino sugar determinations are available for the subunits. The NH2-terminal amino acids are phenylalanine (alpha subunit) and alanine (beta subunit). Preliminary data on COOH-terminal amino acids are provided.  相似文献   
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Autophagy is a key degradative pathway coordinated by external cues, including starvation, oxidative stress, or pathogen detection. Rare are the molecules known to contribute mechanistically to the regulation of autophagy and expressed specifically in particular environmental contexts or in distinct cell types. Here, we unravel the role of RUN and FYVE domain–containing protein 4 (RUFY4) as a positive molecular regulator of macroautophagy in primary dendritic cells (DCs). We show that exposure to interleukin-4 (IL-4) during DC differentiation enhances autophagy flux through mTORC1 regulation and RUFY4 induction, which in turn actively promote LC3 degradation, Syntaxin 17–positive autophagosome formation, and lysosome tethering. Enhanced autophagy boosts endogenous antigen presentation by MHC II and allows host control of Brucella abortus replication in IL-4–treated DCs and in RUFY4-expressing cells. RUFY4 is therefore the first molecule characterized to date that promotes autophagy and influences endosome dynamics in a subset of immune cells.  相似文献   
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Background  

Pseudorabies virus (PRV) is an alphaherpesviruses whose native host is pig. PRV infection mainly causes signs of central nervous system disorder in young pigs, and respiratory system diseases in the adult.  相似文献   
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Background  

Most studies examining the commensal human oral microbiome are focused on disease or are limited in methodology. In order to diagnose and treat diseases at an early and reversible stage an in-depth definition of health is indispensible. The aim of this study therefore was to define the healthy oral microbiome using recent advances in sequencing technology (454 pyrosequencing).  相似文献   
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Wernicke's encephalopathy is a cerebral disorder caused by thiamine (vitamin B1) deficiency (TD). Neuropathologic consequences of TD include region-selective neuronal cell loss and blood-brain barrier (BBB) breakdown. Early increased expression of the endothelial isoform of nitric oxide synthase (eNOS) occurs selectively in vulnerable brain regions in TD. We hypothesize that region-selective eNOS induction in TD leads to altered expression of tight junction proteins and BBB breakdown. In order to address this issue, TD was induced in C57BL/6 wild-type (WT) and eNOS−/− mice by feeding a thiamine-deficient diet and treatment with the thiamine antagonist pyrithiamine. Pair-fed control mice were fed the same diet with additional thiamine. In medial thalamus of TD-WT mice (vulnerable area), increased heme oxygenase-1 and S -nitrosocysteine immunostaining was observed in vessel walls, compared to pair-fed control-WT mice. Concomitant increases in IgG extravasation, decreases in expression of the tight junction proteins occludin, zona occludens-1 and zona occludens-2, and up-regulation of matrix metalloproteinase-9 in endothelial cells were observed in the medial thalamus of TD-WT mice. eNOS gene deletion restored these BBB alterations, suggesting that eNOS-derived nitric oxide is a major factor leading to cerebrovascular alterations in TD. However, eNOS gene deletion only partially attenuated TD-related neuronal cell loss, suggesting the presence of mechanisms additional to BBB disruption in the pathogenesis of these changes.  相似文献   
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