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1.
Genetically modified keratinocytes and fibroblasts are suitable for delivery of therapeutic genes capable of modifying the wound healing process. However, efficient gene delivery is a prerequisite for successful gene therapy of wounds. Whereas adenoviral vectors (Ads) exhibit superior levels of in vivo gene transfer, their transductional efficiency to cells resident within wounds may nonetheless be suboptimal, due to deficiency of the primary adenovirus receptor, coxsackie-adenovirus receptor (CAR). We explored CAR-independent transduction to fibroblasts and keratinocytes using a panel of CAR-independent fiber-modified Ads to determine enhancement of infectivity. These fiber-modified adenoviral vectors included Ad 3 knob (Ad5/3), canine Ad serotype 2 knob (Ad5CAV-2), RGD (Ad5.RGD), polylysine (Ad5.pK7), or both RGD and polylysine (Ad5.RGD.pK7). To evaluate whether transduction efficiencies of the fiber-modified adenoviral vectors correlated with the expression of their putative receptors on keratinocytes and fibroblasts, we analyzed the mRNA levels of CAR, alpha upsilon integrin, syndecan-1, and glypican-1 using quantitative polymerase chain reaction. Analysis of luciferase and green fluorescent protein transgene expression showed superior transduction efficiency of Ad5.pK7 in keratinocytes and Ad5.RGD.pK7 in fibroblasts. mRNA expression of alpha upsilon integrin, syndecan-1 and glypican-1 was significantly higher in primary fibroblasts than CAR. In keratinocytes, syndecan-1 expression was significantly higher than all the other receptors tested. Significant infectivity enhancement was achieved in keratinocytes and fibroblasts using fiber-modified adenoviral vectors. These strategies to enhance infectivity may help to achieve higher clinical efficacy of wound gene therapy.  相似文献   
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乳腺管状小叶癌(Tubulolobular carcinoma,TLC)最初是被作为小叶癌的管状变型。作者总结了27例TLC的组织学、免疫表型和临床特征,并与纯小管癌和经典型小叶癌进行了比较。此组患者年龄43-79岁(中位年龄60岁)。1例双侧乳腺受累,5例病变为多灶性。肿瘤直径0.5-2.5cm,色灰褐,质硬。组织学观察:TLC的肿瘤细胞形成管状和条索状两种结构模式并相互混杂,且两者比例相当(统称为管状小叶模式)。  相似文献   
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Dendritic cells (DC) comprise a system of professional antigen-presenting cells, which induce the stimulation of very rare antigen-specific naive T cells. DC progenitors can be stimulated to differentiate into immature DC by various growth factors, including GM-CSF and IL-4. Here we show that IL-15, in combination with GM-CSF, is a growth factor for murine DC. Murine bone marrow cells, depleted of T cells, B cells, I-A+ cells and Gr-1+ granulocytes, and cultured in the presence of GM-CSF plus IL-15 (IL-15 DC), yielded DC expressing high levels of CD11c and MHC class II molecules, as well as CD11b. These cells expressed significant levels of CD40, CD80 and CD86, and could stimulate allogeneic CD4+ T cells efficiently. Interestingly, IL-15 DC were far superior to DC generated with GM-CSF plus IL-4 in stimulating allogeneic CD8+ T cells in vitro. Consistent with this, IL-15 DC induced much more potent antigen-specific CD8+ T cell responses with high levels of Th1 cytokines in vivo, compared to DC generated with GM-CSF plus IL-4, or with GM-CSF plus TGF-beta, or with GM-CSF alone. Together, these data suggest that IL-15 promotes the development of DC, which induce potent Th1 and Tc1 responses in vivo. This suggests potential roles for these IL-15 DC cells in the immunotherapy of tumors and infectious diseases.  相似文献   
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Germline mutations of the CDKN2 gene in UK melanoma families   总被引:4,自引:1,他引:4  
Germline mutations in CDKN2 on chromosome 9p21, which codes for the cyclin D kinase inhibitor p16, and more rarely, mutations in the gene coding for CDK4, the protein to which p16 binds, underlie susceptibility in some melanoma families. We have sequenced all exons of CDKN2 and analysed the CDK4 gene for mutations in 27 UK families showing evidence of predisposition to melanoma. Five different germline mutations in CDKN2 were found in six families. Three of the mutations (Met53Ile, Arg24Pro and 23ins24) have been reported previously. We have identified two novel CDKN2 mutations (88delG and Ala118Thr) which are likely to be associated with the development of melanoma, because of their co-segregation with the disease and their likely functional effect on the CDKN2 protein. In binding assays the protein expressed from the previously described mutation, Met53Ile, did not bind to CDK4/CDK6, confirming its role as a causal mutation in the development of melanoma. Ala118Thr appeared to be functional in this assay. Arg24Pro appeared to bind to CDK6, but not to CDK4. No mutations were detected in exon 2 of CDK4, suggesting that causal mutations in this gene are uncommon. The penetrance of these mutant CDKN2 genes is not yet established, nor is the risk of non-melanoma cancer to gene carriers.   相似文献   
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Occupational hypersensitivity to -amylase among bakers and workersin the pharmaceutical industry has been described. We presentthe results of skin tests and in vitro methods used to assess-amylase sensitivity in 259 millers. There was no occupationalcontact with the enzyme in this population. Positive skin teststo this allergen were obtained in 16 subjects (6.18 per cent),specific IgE values were found in seven subjects (2.7 per cent),specific IgG was detected on 45 workers (17.37 per cent) andhigh values for IgG (>2.5 absorbance units) were found in12 subjects (4.63 per cent). Furthermore, specific IgE and IgGcould be determined in several sera by immunoblotting. All these facts suggested that millers were sensitized to Aspergillusoryzae -amylase, although the allergen was not used by theseworkers. A cross-reaction cannot be excluded; however, it isthe authors' opinion that wheat or wheat flour is a naturalsubstrate for fungi and that the moulds that grow on cerealsor cereal-derived by-products need to secrete amylases to supporttheir own development. Hence the workers may be indirectly sensitizedto amylases.  相似文献   
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Twenty-five asthmatic subjects with suspected -amylase hypersensitivitywere studied by skin-prick tests, a capture ELISA, immunoblottingand bronchial provocation tests. At the same time, differentamylases were analysed by SDS-PAGE and immunoblotting usinga polyclonal rabbit antiserum. Eight patients showed a positivebronchial response to amylase. Seven of them had positive skin-pricktests, with this method being the most sensitive approach fordiagnosis. However, in four cases, skin tests were also positivealthough the patients had a negative provocation test, thusdemonstrating that skin tests are not specific. ELISA and blottingshowed similar results in terms of sensitivity and specificity.The enzymes used by the workers included several antigens besides-amylase. The rabbit antiserum to -amylase detected a proteinin a wheat flour extract. In one case, the IgE antibodies werespecific only for a contaminant of lower molecular weight thanamylase. These facts suggest that proteins from the culturemedium could be responsible for some cases of amylase hypersensitivity,making the diagnosis difficult. The presence of amylase in anotherenzymatic extract, a protease produced by Aspergillus oryzae,was proved by means of skin tests and immunoblotting, thus demonstratingthe allergenic properties of this enzymatic preparation.  相似文献   
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BACKGROUND: Liver function after transplantation is determined by the quality of the donor organ and the influences of preservation, flush, and reperfusion injury. In this regard, cell death (apoptosis) plays an important role in organ preservation and rejection. Therefore, we examined the possibility of genetic modification of the liver graft with a recombinant adenovirus vector encoding the Bcl-2 gene to reduce apoptosis during the preservation time. METHODS: Liver grafts from C57B1/6 mice were procured and preserved using standard techniques. A replication defective adenovirus vector (deltaE1) containing the human Bcl-2 gene (AdCMVhBcl-2) was developed in our laboratory. An adenovirus vector encoding an irrelevant gene (Escherichia coli beta-galactosidase) was used as a control. Each mouse received 1 x 10(9) plaque forming units administered i.v. 48 hr before the liver procurement. Analyses of liver enzyme activities were determined in the preservation solution. Apoptosis in liver biopsies was determined by DNA fragmentation with an in situ histochemical assay. RESULTS: Immunohistochemical analysis and RT-PCR confirmed the expression of hBcl-2 in the grafts. Grafts from livers expressing hBcl-2 showed significant reduction of the aspartame amino transferase (AST) and lactate dehydrogenase (LDH) release compared with grafts from the control groups. After rewarming, significant cytoprotection was also observed in grafts from animals treated with AdCMVhBcl-2. Histological analysis correlated with the hepatocellular injury determined with transaminases and LDH in the preservation solution. Significant reduction in the number of apoptotic cells was observed in grafts expressing hBcl-2. CONCLUSIONS: We have demonstrated a novel approach to reducing the preservation injury to liver grafts with the human Bcl-2 gene. This approach may allow a longer preservation time, potentially reduce the incidence of primary nonfunction, decrease the immunogenicity of the cold injured organ, and increase the safer use of "marginal" liver grafts.  相似文献   
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