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951.
Soybean (Glycine max. Merrill. cv. Fayette) cotyledonary nodes were transformed with bean pod mottle virus (BPMV) coat protein precursor (CP-P) gene via Agrobacterium-mediated transformation. The transformation rate was low, and only five primary transformants derived from five different cotyledons were obtained from 400 original cotyledons. Southern blot hybridization verified the integration of the BPMV CP-P gene. Inheritance and expression of this gene in R1 plants were also demonstrated. About 30% of R2 plants derived from one transgenic line showed complete resistance to BPMV infection, as assessed by symptomatology and ELISA, suggesting that homozygous, but not hemizygous, plants exhibit the resistant phenotype.Abbreviations BAP 6-benzyladenine phosphate - BPMV bean pod mottle virus - CP-P coat protein-precursor - CTAB hexadecyltrimethylammonium bromide - DAS-ELISA double antibody sandwich-enzyme-linked immunosorbent assay - IBA indole-butyric acid - kbp kilobase pairs - MES 2-(N-Morpholino)ethanesulfonic acid - NOS nopaline synthase - NPTII neomycin phosphotransferase II - NTP nucleoside triphosphate - PBS phosphate-buffered saline - PCR polymerase chain reaction - PVP polyvinyl pyrrolidone - VPg viral genome-linked protein  相似文献   
952.
The aim of this study was to explain whether serum autotaxin (ATX) activity might be a target for regulation of liver fibrosis and to evaluate the hepatoprotective and antifibrotic effects of histidine in thioacetamide (TAA)-induced liver fibrosis in rats. This study was carried out on 100 Wistar Albino rats, classified into five groups, each containing 20 rats: Group I (control group), Group II: rats were given histidine intraperitoneally, Group III: rats were injected intraperitoneally with TAA, Group IV: rats were injected with L-histidine together with TAA, and Group V: rats were injected with TAA for 1 month then treated with intraperitoneal injection of L-histidine for another month. At the end of experiment, blood and liver were collected for determination of some liver enzymes, plasma total antioxidant capacity (TAC), serum ATX activity, and liver tissue hydroxyproline. Thioacetamide treatment caused significant increases in liver enzymes, ATX activities, and liver hydroxyproline, but a significant decrease in plasma's TAC. Upon treatment with histidine, a significant decrease in liver enzymes, ATX activities, and liver hydroxyproline was observed with a significant increase in plasma TAC in Group IV and a significant decrease in Group V. Histidine as an antioxidant has a protective effect on TAA-induced liver fibrosis; it is beneficial in rats not only by inhibition of collagen synthesis and increasing TAC but also by inhibition of ATX activities thus reducing its capacity to produce lysophosphatidic acid, which has a role in liver fibrosis.  相似文献   
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An indirect format enzyme-linked immuno-sorbent assay (ELISA) on graphite rods ( 0.8 mm x 20 mm) and, for comparison, on microtiter plates has been developed against terbuthylazine. For this purpose, a series of 2-aminoalkyl-4-chloro-6-terbuthyl-s-triazine-2,6-diamine ELISA haptens with alkyl spacer lengths of 2, 4, 6, and 8 CH2 groups has been synthesized. The graphite rods or the microtiter plates were covered by a polymerized glutaraldehyde network, and the ELISA haptens have been coupled by imino coupling to the free aldehyde groups of that network. epsilon-Aminocaproic acid has been used as an agent to block unspecific binding sites. The ELISA was run in a competitive mode, where the immobilized ELISA hapten and the solute terbuthylazine as a target analyte compete for the solute antibody.  相似文献   
955.

Background

Novel tuberculosis vaccines should be safe, immunogenic, and effective in various population groups, including HIV-infected individuals. In this phase II multi-centre, double-blind, placebo-controlled trial, the safety and immunogenicity of the novel H1/IC31 vaccine, a fusion protein of Ag85B-ESAT-6 (H1) formulated with the adjuvant IC31, was evaluated in HIV-infected adults.

Methods

HIV-infected adults with CD4+ T cell counts >350/mm3 and without evidence of active tuberculosis were enrolled and followed until day 182. H1/IC31 vaccine or placebo was randomly allocated in a 5∶1 ratio. The vaccine was administered intramuscularly at day 0 and 56. Safety assessment was based on medical history, clinical examinations, and blood and urine testing. Immunogenicity was determined by a short-term whole blood intracellular cytokine staining assay.

Results

47 of the 48 randomised participants completed both vaccinations. In total, 459 mild or moderate and 2 severe adverse events were reported. There were three serious adverse events in two vaccinees classified as not related to the investigational product. Local injection site reactions were more common in H1/IC31 versus placebo recipients (65.0% vs. 12.5%, p = 0.015). Solicited systemic and unsolicited adverse events were similar by study arm. The baseline CD4+ T cell count and HIV viral load were similar by study arm and remained constant over time. The H1/IC31 vaccine induced a persistent Th1-immune response with predominately TNF-α and IL-2 co-expressing CD4+ T cells, as well as polyfunctional IFN-γ, TNF-α and IL-2 expressing CD4+ T cells.

Conclusion

H1/IC31 was well tolerated and safe in HIV-infected adults with a CD4+ Lymphocyte count greater than 350 cells/mm3. The vaccine did not have an effect on CD4+ T cell count or HIV-1 viral load. H1/IC31 induced a specific and durable Th1 immune response.

Trial registration

Pan African Clinical Trials Registry (PACTR) PACTR201105000289276  相似文献   
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Excess visceral adiposity may predispose to chronic diseases like hypertension and type 2 diabetes with a high risk for coronary artery disease. Adipose tissue secreted cytokines and oxidative stress play an important role in chronic disease progression. To combat adiposity, plant-derived triterpenes are currently receiving much attention as they possess antioxidant and anti-inflammatory properties and the ability to regulate glucose and lipid metabolism. In the search for potential antiobese compounds from natural sources, this study evaluated the effects of oleanolic acid (OA), a pentacyclic triterpene commonly present in fruits and vegetables, in glucose tolerance test and on high-fat diet (HFD)-induced obesity in mice. Adult male Swiss mice treated or not with OA (10 mg/kg) were fed a HFD during 15 weeks. Sibutramine (SIB) treated group (10 mg/kg) was included for comparison. Weekly body weights, food and water consumption were measured, and at the end of study period, the levels of blood glucose and lipids, plasma hormone levels of insulin, ghrelin and leptin, and the visceral abdominal fat content were analysed. Mice treated with OA and fed a HFD showed significantly (p < 0.05) improved glucose tolerance, decreased body weights, visceral adiposity, blood glucose, plasma lipids relative to their respective controls fed no OA. Additionally, OA treatment, while significantly elevating the plasma hormone level of leptin, decreased the level of ghrelin. However, it caused a greater decrease in plasma amylase activity than lipase. Sibutramine-treated group also manifested similar effects like OA except for blood glucose level that was not different from HFD control. These findings suggest that OA ameliorates visceral adiposity and improves glucose tolerance in mice and thus has an antiobese potential through modulation of carbohydrate and fat metabolism.  相似文献   
960.
We investigated the relative contribution of COX-1 and/or COX-2 to oxidative damage, prostaglandin E2 (PGE2) production and hippocampal CA1 neuronal loss in a model of 5 min transient global cerebral ischemia in gerbils. Our results revealed a biphasic and significant increase in PGE2 levels after 2 and 24-48 h of reperfusion. The late increase in PGE2 levels (24 h) was more potently reduced by the highly selective COX-2 inhibitor rofecoxib (20 mg/kg) relative to the COX-1 inhibitor valeryl salicylate (20 mg/kg). The delayed rise in COX catalytic activity preceded the onset of histopathological changes in the CA1 subfield of the hippocampus. Post-ischemia treatment with rofecoxib (starting 6 h after restoration of blood flow) significantly reduced measures of oxidative damage (glutathione depletion and lipid peroxidation) seen at 48 h after the initial ischemic episode, indicating that the late increase in COX-2 activity is involved in the delayed occurrence of oxidative damage in the hippocampus after global ischemia. Interestingly, either selective inhibition of COX-2 with rofecoxib or inhibition of COX-1 with valeryl salicylate significantly increased the number of healthy neurons in the hippocampal CA1 sector even when the treatment began 6 h after ischemia. These results provide the first evidence that both COX isoforms are involved in the progression of neuronal damage following global cerebral ischemia, and have important implications for the potential therapeutic use of COX inhibitors in cerebral ischemia.  相似文献   
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