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11.
BACKGROUND: Our objectives were to identify serum marker proteins in rats that might serve as sensitive indicators of hepatomegaly, hepatocellular necrosis, or hepatobiliary injury and to use them to analyze data from a collaborative proteomics project. METHODS: In each of 4 studies comprising the collaborative project, rats were given 1 of 4 compounds that target the liver through different mechanisms. Sera and liver samples were collected by terminal bleeds at 1 of 3 postdose time points. Sera were depleted of major secretory proteins and then separated into protein features by 2-dimensional gel electrophoresis (2DGE). Liver specimens were also processed and subjected to 2DGE. Protein spots that significantly increased or decreased in quantity after drug treatment were recovered, digested, analyzed by mass spectroscopy, and compared with available databases for identification. Criteria for further consideration were (a) temporal expression (i.e., increase or decrease at early, fulminant, or recovery periods), (b) known biological function, (c) probable hepatic origin, and (d) any previous association with toxicity in published studies. Markers that changed significantly at the early time point were important because of their potential sensitivity for signaling minimal damage. RESULTS: Vitamin D-binding protein, paraoxonase, cellular retinol-binding protein, malate dehydrogenase, F-protein, and purine nucleoside phosphorylase were identified as empirically confirmed serum markers for hepatic effects in drug-treated rats. CONCLUSION: Proteomics can be applied for the identification and confirmation of peripheral biomarkers for altered liver function after toxicant exposure.  相似文献   
12.
We describe a technique for creating a continuous curvilinear capsulorhexis (CCC) using an endoscope. Three 2.0 mm limbal incisions 120 degrees apart were made in 4 cadaver eyes. The anterior capsule was stained with trypan blue 0.1% (Vision Blue). Under endoscopic visualization, a CCC was attempted in each of the 4 globes. It was completed in 1 of them. Endoscopy provides a safe and effective tool to visualize the anterior chamber and perform a CCC when there is a poor view through the cornea.  相似文献   
13.
HIV-1 integrase is a critical enzyme for replication of HIV, and its inhibition is one of the most promising new drug targets for anti-retroviral therapy with potentially significant advantages over existing therapies. In this Note, the isolation, structure elucidation, and absolute stereochemistry of integrasone, a novel polyketide, derived from an unidentified sterile mycelium have been described. This bicyclic dihydroxy epoxide lactone inhibited the strand transfer reaction of HIV-1 integrase with an IC(50) of 41 microM.  相似文献   
14.
Certain naturally occurring flavonoids affect immunoregulatory activities in vitro and in vivo against cytokine production. Since tumor necrosis factor (TNF)-alpha is one of the major inflammatory cytokines, the effects of various dietary flavonoids on TNF-alpha production in lipopolysaccharide (LPS)-stimulated J774.1 cells were evaluated in vitro. Flavones, flavonols, and chalcone are the most potent inhibitors of production of TNF-alpha. Flavanone, naringenin, anthocyanidin, pelargodinin, and cyanidin exhibit moderate inhibitory activity. In contrast, genistein isoflavone displays weak inhibition, while eriodictyol flavanone is inactive. It is clear that the double bond between carbons 2 and 3 and the ketone group at position 4 of flavonoids are necessary for potent inhibitory effect. The difference in inhibitory action appears to depend on the categorized subclass of flavonoids.  相似文献   
15.
Adult Anopheles subpictus from Sri Lanka show a broad spectrum of resistance towards organophosphate insecticides but not to carbamates in contrast to the broad resistance to organophosphates and carbamates reported earlier for An. nigerrimus. In both species the frequency of resistance to malathion and fenitrothion increased between 1980 and 1987, despite the ban on agricultural use of these two compounds and the restriction of malathion to indoor residual spraying in malaria control since 1977. In contrast, An. culicifacies shows only low level specific resistance to malathion at a very low frequency. As An. subpictus breeds to a large extent in paddy fields which are highly contaminated by agricultural pesticides, and is highly endophilic, selection for resistance theoretically could occur through both agricultural and anti-malarial pesticide use. However, the anti-malarial use of malathion may have been less important, taking into consideration the low level of resistance of An. culicifacies which is also highly endophilic but breeds to a negligible extent in paddy fields.  相似文献   
16.
This survey examined 59,158 children from 87 schools in 17 out of 24 districts in Sri Lanka for goitre. The overall prevalence rate was 18.8%: 23.2% for girls and 14.0% for boys. Prevalence in districts varied from 30.2% in Kalutara to 6.5% in Matale. It was higher in rural than urban areas, and in inland than coastal areas. The sex ratio of prevalence rates was directly related and the ratio of palpable to visible goitre was inversely related to the severity of the endemic. It is suggested that for a rapid epidemiological assessment when the latter ratio is less than four, it is indicative of endemicity for public health purposes and calls for intervention. The iodination of salt is both practical and feasible in Sri Lanka.  相似文献   
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18.
Puppets for Prevention: "playing safe is playing smart"   总被引:2,自引:0,他引:2  
Successful use of puppetry for education of children is well documented in literature. However, in this age of mechanically animated toys and sophisticated children, we have matched realism with an element of high technology for optimal learning experience. This 15-minute video is the basis for a burn prevention and education program entitled "Puppets for Prevention." The video is a creative and lively discussion between two puppets. The dialogue is delivered in a manner that is not threatening. It covers the child's hospitalization, types of burns and how they heal, feelings on scarring and returning to school as well as the conventional preventive measures. The realism in the video comes from the puppets, which have been specially constructed to teach children about burns, skin grafts, donor sites, and rehabilitative garments. High technology comes from the use of the puppets' pretaped accounts incorporated with the actual puppet show creating a completely integrated presentation. Initial response has been overwhelmingly positive. Our survey of one control group one week after viewing the puppet show demonstrated that all found it favorable. Forty percent remembered basic first aid and 65% mentioned significant points of the presentation. We plan to continue ongoing evaluations with the estimated 1,500 children who will view our program this school year.  相似文献   
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Administration of the CD28 superagonistic antibody JJ316 is an efficient means to treat autoimmune diseases in rats, but the humanized antibody TGN1412 caused devastating side effects in healthy volunteers during a clinical trial. Here we show that JJ316 treatment of rats induced a dramatic redistribution of T lymphocytes from the periphery to the secondary lymphoid organs, resulting in severe T lymphopenia. Live imaging of secondary lymphoid organs revealed that JJ316 administration almost instantaneously (<2 minutes) arrested T cells in situ. This reduction in T cell motility was accompanied by profound cytoskeletal rearrangements and increased cell size. In addition, surface expression of lymphocyte function-associated antigen-1 was enhanced, endothelial differentiation sphingolipid G protein-coupled receptor 1 and L selectin levels were downregulated, and the cells lost their responsiveness to sphingosine 1-phosphate-directed migration. These proadhesive alterations were accompanied by signs of strong activation, including upregulation of CD25, CD69, CD134, and proinflammatory mediators. However, this did not lead to a cytokine storm similar to the clinical trial. While most of the early changes disappeared within 48 hours, we observed that CD4+CD25+FoxP3+ regulatory T cells experienced a second phase of activation, which resulted in massive cell enlargement, extensive polarization, and increased motility. These data suggest that CD28 superagonists elicit 2 qualitatively distinct waves of activation.  相似文献   
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