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41.
Adeno-Associated Viral Vector-Mediated Interleukin-10 Prolongs Allograft Survival in a Rat Kidney Transplantation Model 总被引:5,自引:0,他引:5
B. Chen M. H. Kapturczak R. Joseph J. F. George M. Campbell-Thompson C. H. Wasserfall M. A. Atkinson C. C. Tisher T. R. Flotte A. Agarwal S. Chen 《American journal of transplantation》2007,7(5):1112-1120
Interleukin-10 (IL-10) is a pleiotropic cytokine that plays a pivotal role in the regulation of immune responses. Hence, we evaluated the effects of a recombinant adeno-associated viral vector 1 (rAAV1) encoding rat IL-10 (rAAV1-IL-10) in a rat model of kidney allograft rejection. Dark Agouti rat kidneys were transplanted into Wistar-Furth (WF) rats 8 weeks following a single intramuscular administration of either rAAV1-IL-10 or rAAV1-green fluorescence protein (GFP). Isografts (WF-WF) served as an additional experimental control. Both allograft and isograft recipients received daily cyclosporine (10 mg/kg) for 14 days after transplantation. Serum IL-10 levels increased at 8, 12 and 16 weeks following vector administration in rAAV1-IL-10-treated animals, but not in rAAV1-GFP and isograft groups. rAAV1-IL-10 treatment resulted in lower BUN and creatinine levels (p<0.001), as well as increased allograft survival rates from 22% to 90%. Allograft histological abnormalities were significantly attenuated in the rAAV1-IL-10-treated rats compared with those of rAAV1-GFP controls. Serum levels of proinflammatory cytokines such as growth-related oncogene were also significantly higher in the rAAV1-GFP group than in the rAAV1-IL-10 group. These data suggest delivery of IL-10 using a rAAV1 vector improves renal function and prolongs graft survival in a rat model of kidney transplant rejection. 相似文献
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K. M. Boyle D. Petty† A. G. Chalmers† P. Quirke‡ A. Cairns‡ P. J. Finan P. M. Sagar D. Burke 《Colorectal disease》2005,7(3):232-240
OBJECTIVE: The outcome after surgical treatment of rectal cancer may be influenced by the technical difficulty of the operation, which is thought to be affected by pelvic size. The aim of this study was to examine the association between bony pelvic dimensions and CRM involvement. PATIENTS AND METHODS: All patients with primary rectal cancer between December 1999 and January 2002 were studied. Staging was performed by pelvic MRI. Nine pelvic dimensions were measured from the MR images on a workstation. Pathology reports were obtained for all patients and the mesorectal specimen was examined. Technical difficulty was assessed by circumferential resection margin (CRM) involvement. RESULTS: Of 126 patients with primary rectal cancer, 88 had staging MRI and rectal excision; there were significant differences between the sexes in all 9 pelvic dimensions (P < 0.05). In females, the interspinous diameter was significantly shorter in patients with CRM involvement compared with patients with a negative CRM. In female patients predicted to have a negative CRM, the anteroposterior diameter of the inlet, the anteroposterior diameter of the midplane and the transverse diameter of the midplane (interspinous distance) were significantly shorter in patients who actually had a positive CRM compared with those in whom the CRM was negative. In male patients, there was no correlation between pelvic dimensions and CRM status. CONCLUSIONS: In certain patients with rectal cancer, CRM positivity may be predicted from pre-operative MRI pelvic measurements. This may influence the choice of adjuvant therapy. 相似文献
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Kalpana Agarwal Anita Mukherjee Archana Sharma Ramesh Sharma Kuldip Raj Bhardwaj Soumitra Sen 《Environmental and molecular mutagenesis》1992,19(4):323-326
Fenfluramine, an amphetamine derivative used in the treatment of obesity, has been evaluated in vivo in the bone marrow cells of Swiss albino mice using two cytogenetic endpoints for assessing its genotoxic and clastogenic potentials. Concentrations of 0.75, 1.5, 3.0, and 5.0 mg/kg b.w. were administered orally for the study of sister chromatid exchange frequencies and chromosome aberrations (CA). SCE frequencies showed a positive dose response; 1.5 mg/kg being the minimum effective concentration. Fen caused a prolongation of cell cycle at all concentrations. Except for the minimum therapeutic dose (0.75 mg), all other doses (1.5, 3.0, and 5.0 mg) showed a significant increase in the percentage of damaged cells over that of the vehicle control. The degree of clastogenicity was directly proportional to the dosage used and inversely related with the duration of treatment. A gradual reduction of the clastogenic potential was observed after 12 and 24 hr of exposure, indicating that the maximum effect occurs at the middle or late synthetic phase of the cell cycle. This study, probably the first detailed screening of the drug for its genotoxicity, shows that Fen is moderately clastogenic and a DNA damaging agent in vivo. 相似文献
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Vijay K. Singh Sumita Biswas Krishna B. Mathur Wahajul Haq Satyendra K. Garg Shyam S. Agarwal 《Immunologic research》1998,17(3):345-368
Splenopentin (SP-5, Arg-Lys-Glu-Val-Tyr) and thymopentin (TP-5, Arg-Lys-Asp-Val-Tyr) are synthetic immunomodulating peptides corresponding to the region 32–34 of a splenic product called splenin (SP) and the thymic hormone thymopoietin (TP), respectively. TP was originally isolated as a 5-kDa (49-amino acids) protein from bovine thymus while studying effects of the thymic extracts on neuromuscular transmission and was subsequently observed to affect T cell differentiation and function. TP I and II are two closely related polypeptides isolated from bovine thymus. A radioimmunoassay for TP revealed a crossreaction with a product found in spleen and lymph node. This product, named splenin, differs from TP only in position 34, aspartic acid for bovine TP and glutamic acid for bovine splenin and it was called TP III as well. Synthetic pentapeptides (TP-5) and (SP-5), reproduce the biological activities of TP and SP, respectively. It is now evident that various forms of TPs were created by proteolytic cleavage of larger proteins during isolation. cDNA clones have been isolated for three alternatively spliced mRNAs that encodes three distinct human T cell TPs. The immunomodulatory properties of TP, SP, TP-5, SP-5 and some of their synthetic analogs reported in the literature have been briefly reviewed. 相似文献
47.
Recently, we and others showed that the components of green tea may be useful cancer chemopreventive agents. It has been suggested that (-)-epigallocatechin-3-gallate (EGCG), the major constituent in green tea, may possess antitumor-promoting and/or anticarcinogenic effects in rodent tumor bioassay systems. During the chemical analysis of various green tea products, we found a traditionally preserved preparation of green tea used by tribes in the Himalayan region of Sikkim, India that was rich in EGCG. EGCG was isolated from this tea product, and its inhibitory effects were evaluated against the binding of topically applied 3H-labeled polycyclic aromatic hydrocarbons (PAHs) to epidermal DNA and 12-O-tetradecanoylphorbol-13-acetate (TPA) caused induction of epidermal ornithine decarboxylase (ODC) activity in Sencar mice, the short-term markers of tumor initiation and tumor promotion, respectively. Preapplication of EGCG resulted in significant inhibition (p less than 0.05) in the binding of [3H]PAH to epidermal DNA. Similarly, the topical application of EGCG resulted in significant inhibition (p less than 0.005) in TPA-caused induction of epidermal ODC activity. In further studies, we assessed the anti-skin tumor-initiating effect of EGCG in Sencar mice in an initiation-promotion protocol. The application of EGCG before challenge with 7,12-dimethylbenz[a]anthracene as tumor initiator resulted in significant reduction both in percentage of mice with tumors and number of tumors per mouse compared with a non-EGCG-pretreated group of animals. The results of the present study suggest that the green tea preparation from Sikkim may be a good source for the isolation of EGCG and that this compound may have significant potential as a cancer chemopreventive agent. 相似文献
48.
Sturge-Weber syndrome is a rare neurocutaneous disorder characterized by a facial nevus flammeus and extensive angiomatous changes involving the leptomeninges, the dura, and vessels of the gray and white matter. Oculodermal melanocytosis is characterized by hyperpigmentation of the facial skin in the distribution of the ophthalmic, maxillary, and occasionally mandibular division of the trigeminal nerve. 相似文献
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