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The effects of mechanoreceptor stimulation and subsequent ATP release in spinal cord injured and normal bladders was examined to demonstrate if spinal cord injury (SCI) modulates the basal or evoked release of ATP from bladder urothelium and whether intravesical botulinum toxin A (BTX-A) administration inhibits urothelial ATP release, a measure of sensory nerve activation. A Ussing chamber was used to isolate and separately measure resting and mechanoreceptor evoked (e.g. hypoosmotic stimulation) ATP release from urothelial and serosal sides of the bladder. Following spinal cord injury, resting urothelial release of ATP was ninefold higher than that of normal rats. Botulinum toxin A instillation did not significantly affect the resting release of ATP after spinal cord injury. Evoked ATP release following hypoosmotic stimulation was significantly higher in chronic spinal cord injured compared to normal rat bladders. However, botulinum toxin A treatment markedly reduced ATP release in spinal cord injured bladders by 53% suggesting that ATP release by mechanoreceptor stimulation, as opposed to basal release, occurs by exocytotic mechanisms. In contrast, there was no significant difference in basal or evoked ATP release from bladder serosa following spinal cord injury. Moreover, intravesical instillation of botulinum toxin A did not affect ATP release from the serosal side after spinal cord injury, suggesting that its effects were confined to the urothelial side of the bladder preparation. In summary: (1) increased release of ATP from the urothelium of spinal cord injured bladders may contribute to the development of bladder hyperactivity and, (2) mechanoreceptor stimulated vesicular ATP release, as opposed to basal non-vesicular release of ATP, is significantly inhibited in spinal cord injured bladders by intravesical instillation of botulinum toxin A. These results may have important relevance in our understanding of the mechanisms underlying plasticity of bladder afferent pathways following SCI.  相似文献   
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Mast cell activation through the high affinity IgE receptor (FcepsilonRI) is a critical component of atopic inflammation. The cytokine TGF-beta1 has been shown to inhibit IgE-dependent mast cell activation, possibly serving to dampen mast cell-mediated inflammatory responses. We present proof that TGF-beta1 inhibits mast cell FcepsilonRI expression through a reversible pathway that diminishes protein, but not mRNA, expression of the FcepsilonRI subunit proteins alpha, beta, and gamma. The stability of the expressed proteins and the assembled cell surface complex was unaltered by TGF-beta1 treatment. However, TGF-beta1 decreased the rate of FcepsilonRI beta-chain synthesis, arguing that this inhibitory cytokine exerts its effects at the level of mRNA translation. TGF-beta1 consistently diminished FcepsilonRI expression on cultured human or mouse mast cells as well as freshly isolated peritoneal mast cells. The related cytokines, TGF-beta2 and TGF-beta3, had similar effects. We propose that TGF-beta1 acts as a negative regulator of mast cell function, in part by decreasing FcepsilonRI expression.  相似文献   
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The production of biofuel using thermostable bacterial lipase from hot spring bacteria out of low-cost agricultural residue olive oil cake is reported in the present paper. Using a lipase enzyme from Bacillus licheniformis, a 66.5% yield of methyl esters was obtained. Optimum parameters were determined, with maximum production of lipase at a pH of 8.2, temperature 50.8°C, moisture content of 55.7%, and biosurfactant content of 1.693?mg. The contour plots and 3D surface responses depict the significant interaction of pH and moisture content with biosurfactant during lipase production. Chromatographic analysis of the lipase transesterification product was methyl esters, from kitchen waste oil under optimized conditions, generated methyl palmitate, methyl stearate, methyl oleate, and methyl linoleate.  相似文献   
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A 75 kDa serine protease having prolyl oligopeptidase activity has been purified from Setaria cervi, a bovine filarial parasite. The MALDI-MS/MS analysis of the purified protein revealed 6 peptides showing nearest match S9A (prolyl oligopeptidase) family protein from Plesiocystis pacifica. The ScPOP was found to be unique compared to mammalian POP with respect to its kinetic properties. To elucidate its role, filarial parasites were exposed to specific inhibitor of POP, Z-Pro-prolinal (ZPP) for 8?h. The inhibition of POP induced calcium signaling via phospholipase c stimulation which further triggered mitochondrial mediated apoptosis in filarial parasites.  相似文献   
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Most of what is known about coastal free-living and attached bacterial diversity is based on open coasts, with high particulate and nutrient riverine supply, terrestrial runoffs, and anthropogenic activities. The Magdalen Islands in the Gulf of St. Lawrence (Canada) are dominated by shallow lagoons with small, relatively pristine catchments and no freshwater input apart from rain. Such conditions provided an opportunity to investigate coastal free-living and attached marine bacterial diversity in the absence of confounding effects of steep freshwater gradients. We found significant differences between the two communities and marked temporal patterns in both. Taxonomic richness and diversity were greater in the attached than in the free-living community, increasing over summer, especially within the least abundant bacterial phyla. The highest number of reads fell within the SAR 11 clade (Pelagibacter, Alphaproteobacteria), which dominated free-living communities. The attached communities had deeper phylum-level diversity than the free-living fraction. Distance-based redundancy analysis indicated that the particulate organic matter (POM) concentration was the main variable separating early and late summer samples with salinity and temperature changes also significantly correlated to bacterial community structure. Our approach using high-throughput sequencing detected differences in free-living versus attached bacteria in the absence of riverine input, in keeping with the concept that marine attached communities are distinct from cooccurring free-living taxa. This diversity likely reflects the diverse microhabitats of available particles, implying that the total bacterial diversity in coastal systems is linked to particle supply and variability, with implications for understanding microbial biodiversity in marine systems.  相似文献   
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Background:

Arthroscopic surgery for degenerative meniscal tears is a commonly performed procedure, yet the role of conservative treatment for these patients is unclear. This systematic review and meta-analysis evaluates the efficacy of arthroscopic meniscal débridement in patients with knee pain in the setting of mild or no concurrent osteoarthritis of the knee in comparison with nonoperative or sham treatments.

Methods:

We searched MEDLINE, Embase and the Cochrane databases for randomized controlled trials (RCTs) published from 1946 to Jan. 20, 2014. Two reviewers independently screened all titles and abstracts for eligibility. We assessed risk of bias for all included studies and pooled outcomes using a random-effects model. Outcomes (i.e., function and pain relief) were dichotomized to short-term (< 6 mo) and long-term (< 2 yr) data.

Results:

Seven RCTs (n = 805 patients) were included in this review. The pooled treatment effect of arthroscopic surgery did not show a significant or minimally important difference (MID) between treatment arms for long-term functional outcomes (standardized mean difference [SMD] 0.07, 95% confidence interval [CI] −0.10 to 0.23). Short-term functional outcomes between groups were significant but did not exceed the threshold for MID (SMD 0.25, 95% CI 0.02 to 0.48). Arthroscopic surgery did not result in a significant improvement in pain scores in the short term (mean difference [MD] 0.20, 95% CI −0.67 to 0.26) or in the long term (MD −0.06, 95% CI −0.28 to 0.15). Statistical heterogeneity was low to moderate for the outcomes.

Interpretation:

There is moderate evidence to suggest that there is no benefit to arthroscopic meniscal débridement for degenerative meniscal tears in comparison with nonoperative or sham treatments in middle-aged patients with mild or no concomitant osteoarthritis. A trial of nonoperative management should be the first-line treatment for such patients.Arthroscopic meniscal débridement is one of the most commonly performed procedures in orthopedic surgery. More than 700 000 such procedures are performed each year in the United States, and more than 4 million are performed each year worldwide, with substantial economic and social burdens.16 Many patients who undergo arthroscopic meniscal débridement have concurrent osteoarthritis, and orthopedic surgeons are often challenged to determine the true cause of patients’ symptoms: the meniscal tear, osteoarthritis or a combination of both.7Although 2 well-designed randomized controlled trials (RCTs)8,9 have shown a lack of efficacy for arthroscopic surgery in patients with severe and advanced knee arthritis, many patients present with degenerative meniscal tears and mild or minimal concurrent osteoarthritis.10 Patients with degenerative meniscal tears in the setting of mild osteoarthritis may experience functional improvement or pain relief with arthroscopic surgery,1114 but the role of conservative treatment is unclear.1517 Arthroscopic surgery involves the potential for complications, which must be weighed against the prognosis for relief from presenting symptoms.6,18The objective of this systematic review and meta-analysis was to evaluate the efficacy of arthroscopic meniscal débridement in comparison with nonoperative or sham treatments in patients with degenerative meniscal tears and knee pain with regard to function and pain relief in the short term (< 6 mo) and long term (< 2 yr).  相似文献   
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