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901.
The current sensor networks are assumed to be designed for specific applications, having data communication protocols strongly coupled to applications. The future sensor networks are envisioned as comprising heterogeneous devices assisting to a large range of applications. To achieve this goal, a new architecture approach is needed, having application specific features separated from the data communication protocol, while influencing its behavior. We propose a Web Services approach for the design of sensor network, in which sensor nodes are service providers and applications are clients of such services. Our main goal is to enable a flexible architecture in which sensor networks data can be accessed by users spread all over the world.  相似文献   
902.
This study sought to evaluate the effects of a single session of exercise on the expression of Hsp70, of c-jun N-terminal kinase (JNK), and insulin receptor substrate 1 serine 612 (IRSser612) phosphorylation in the skeletal muscle of obese and obese insulin-resistant patients. Twenty-seven volunteers were divided into three experimental groups (eutrophic insulin-sensitive, obese insulin-sensitive, and obese insulin-resistant) according to their body mass index and the presence of insulin resistance. The volunteers performed 60 min of aerobic exercise on a cycle ergometer at 60 % of peak oxygen consumption. M. vastus lateralis samples were obtained before and after exercise. The protein expressions were evaluated by Western blot. Our findings show that compared with paired eutrophic controls, obese subjects have higher basal levels of p-JNK (100 ± 23 % vs. 227 ± 67 %, p = 0.03) and p-IRS-1ser612 (100 ± 23 % vs. 340 ± 67 %, p < 0.001) and reduced HSP70 (100 ± 16 % vs. 63 ± 12 %, p < 0.001). The presence of insulin resistance results in a further increase in p-JNK (460 ± 107 %, p < 0.001) and a decrease in Hsp70 (46 ± 5 %, p = 0.006), but p-IRS-1ser612 levels did not differ from obese subjects (312 ± 73 %, p > 0.05). Exercise reduced p-JNK in obese insulin-resistant subjects (328 ± 33 %, p = 0.001), but not in controls or obese subjects. Furthermore, exercise reduced p-IRS-1ser612 for both obese (122 ± 44 %) and obese insulin-resistant (185 ± 36 %) subjects. A main effect of exercise was observed in HSP70 (p = 0.007). We demonstrated that a single session of exercise promotes changes that characterize a reduction in cellular stress that may contribute to exercise-induced increase in insulin sensitivity.  相似文献   
903.
904.
A rapid method based on a defined methanol-chloroform-water mixture for the quantitative precipitation of soluble as well as hydrophobic proteins from dilute solutions (e.g., column chromatography effluents) has been developed. The effectiveness of this method is not affected by the presence of detergents, lipids, salt, buffers, and beta-mercaptoethanol.  相似文献   
905.
906.
907.
In most viral infections of the central nervous system (CNS), the integrity of brain extracelluar matrix (ECM), oxidative stress and dysfunction in neuronal transmission may contribute to the observed pathology. The purpose of this study was to investigate the role of these factors in demyelinating canine distemper virus (CDV) infections. Regardless of ECM integrity, the expression of metalloproteinase-9 (MMP-9) was visualized in microglial-like cells, whereas the expression of anti-oxidant like-1 (AOP-1) and synaptosomal associated protein (SNAP-25) was frequently detected in Purkinje cells (r(2) = 0.989; p < 0.05), regardless of whether the lesions were classified as acute or chronic. Increased numbers of immunolabeled microglia-like cells and reactive gliosis were observed in advanced cases of demyelinating CDV, suggesting that the expression of AOP-1 and SNAP-25 is correlated with the ultimate death of affected cells. Our findings bring a new perspective to understanding the role of the AOP-1, MMP-9 and SNAP-25 proteins in mediating chronic leukoencephalitis caused by CDV.  相似文献   
908.
Fish intestinal microbiota changes with the diet and this effect is of particular interest considering the increasing substitution of fish meal by plant protein sources. The objective of this work was to study the effects of partial substitution of fish meal with lupin and rapeseed meals on gut microbiota of the gilthead sea bream (Sparus aurata) and in goldfish (Carassius auratus). Faecal, gastrointestinal and intestinal contents were characterized using culture-based and molecular methods. Vibrionaceae was high in faeces and in the intestine of sea bream, while a more diverse microbiota was retrieved from the stomach, where Bacillales and Flavobacteriaceae appeared to be influenced by the diet. PCR-denaturing gradient gel electrophoresis profiles revealed a high diversity of the microbiota transiting in the sea bream digestive tract, with a shift between gastric and intestinal communities, especially in the group fed with lupin meal. The goldfish was different, with a predominance of Aeromonas spp., Shewanella putrefaciens and Staphylococcus spp. among the aerotolerant-cultivable bacteria. The culture-independent methods revealed the presence of anaerobes like Cetobacterium somerae, and that of Vibrio spp., likely in a viable, but noncultivable state. There was a trend towards decreasing diversity in goldfish microbiota with the partial substitution by lupin, which seemed to inhibit some taxa.  相似文献   
909.
The α2β1 antagonist rhodocetin from Calloselasma rhodostoma is a heterotetrameric CLRP (C-type lectin-related protein) consisting of four distinct chains, α, β, γ and δ. Via their characteristic domain-swapping loops, the individual chains form two subunits, αβ and γδ. To distinguish the four chains which share similar molecular masses and high sequence homologies, we generated 11 mAbs (monoclonal antibodies) with different epitope specificities. Four groups of distinct mAbs were generated: the first targeted the rhodocetin β chain, the second group bound to the αβ subunit mostly in a conformation-dependent manner, the third group recognized the γδ subunit only when separated from the αβ subunit, whereas a fourth group interacted with the γδ subunit both in the heterotetrameric molecule and complexed with the integrin α2 A-domain. Using the specific mAbs, we have shown that the rhodocetin heterotetramer dissociates into the αβ and γδ subunit upon binding to the integrin α2 A-domain at both the molecular and cellular levels. After dissociation, the γδ subunit firmly interacts with the α2β1 integrin, thereby blocking it, whereas the rhodocetin αβ subunit is released from the complex. The small molecular interface between the αβ and γδ subunits within rhodocetin is mostly mediated by charged residues, which causes the two dissociated subunits to have hydrophilic surfaces.  相似文献   
910.
Conjugation is a major route of horizontal gene transfer, the driving force in the evolution of bacterial genomes. Antibiotic producing soil bacteria of the genus Streptomyces transfer DNA in a unique process involving a single plasmid-encoded protein TraB and a double-stranded DNA molecule. However, the molecular function of TraB in directing DNA transfer from a donor into a recipient cell is unknown. Here, we show that TraB constitutes a novel conjugation system that is clearly distinguished from DNA transfer by a type IV secretion system. We demonstrate that TraB specifically recognizes and binds to repeated 8 bp motifs on the conjugative plasmid. The specific DNA recognition is mediated by helix α3 of the C-terminal winged-helix-turn-helix domain of TraB. We show that TraB assembles to a hexameric ring structure with a central ~3.1 nm channel and forms pores in lipid bilayers. Structure, sequence similarity and DNA binding characteristics of TraB indicate that TraB is derived from an FtsK-like ancestor protein, suggesting that Streptomyces adapted the FtsK/SpoIIIE chromosome segregation system to transfer DNA between two distinct Streptomyces cells.  相似文献   
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