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21.
Parentini I Bergamini E Cecchi L Cavallini G Donati A Maccheroni M Tamburini I Gorii Z 《Biogerontology》2003,4(6):365-370
Dolichol (D) is a long-chain polyprenoid broadly distributed in the cell membranes, possibly endowed with a free-radical scavenging activity, whose concentration in tissues increases with increasing age. No enzyme pathway for D degradation has been discovered. In order to test the hypothesis that D might undergo a non-enzymatic free-radical mediated decomposition the effects of a xenobiotic agent (carbon tetrachloride, CCl(4)) and ultraviolet-B (UV-B) radiation on D levels were studied in liver cells isolated from male ad libitum fed Sprague-Dawley rats aged 3 or 24 months. Liver cells (90 mg/ml) were incubated in sealed flasks (6 ml cell suspension each) for 0, 5, 10 and 20 min after the addition of 25, 50 or 200 microl CCl(4) in the central well. 50 ml of a 6 mg/ml liver cell suspension were poured in a 120 cm(2) Petri dish and the sediment liver cell monolayer was exposed to UVB radiation for 0, 5, 10, 20 and 40 min. At the given time, cells were taken and D was extracted and assayed by the HPLC procedure. D levels were remarkably higher in older than in younger cells as expected ( P < 0.001). Treatment with CCl(4) and UVB caused a highly significant decrease in D ( P < 0.001) whose percentage was larger in younger than in older cells. The conclusions are that free-radicals generated either by chemical or by physical agents cause a very rapid depletion of D in liver cells, and that the effect of the free radical attack on D decomposition may be lower percentage wise in older than in younger cells, which might account at least in part for the accumulation of D in older tissues. 相似文献
22.
Overexpression of the Notch ligand,Jagged-1, induces alloantigen-specific human regulatory T cells 总被引:14,自引:1,他引:14
Yvon ES Vigouroux S Rousseau RF Biagi E Amrolia P Dotti G Wagner HJ Brenner MK 《Blood》2003,102(10):3815-3821
Graft-versus-host disease (GVHD) represents one of the major complications of allogeneic hematopoietic stem cell transplantation. Techniques to prevent GVHD have included ex vivo T-cell depletion of the graft or prolonged in vivo immunosuppression. Both reduce the frequency and severity of GVHD but also reduce T-cell-mediated graft-versus-malignancy effect, and increase the risk of infection. A major goal in transplantation is to prevent alloreactivity while preserving activity against tumors and infectious agents. We have used activation of the Notch pathway to try to generate T cells able to specifically regulate alloantigen responses. We used allogeneic Epstein-Barr virus lymphoblastoid B cells (EBV-LCLs) as stimulator cells. Such LCLs are excellent (allo) antigen-presenting cells and can be obtained in large numbers even from donors who have received extensive chemo/radiotherapy. We overexpressed a Notch ligand, Jagged-1, in these cells by adenoviral vector transduction. Stimulation of CD45RA+ naive T cells by Jagged-1 EBV-LCL reduces production of interferon-gamma, interleukin-2, and interleukin-5, but up-regulates transforming growth factor-beta 1 synthesis, consistent with induction of a regulatory T-cell phenotype. Transfer of these T cells to fresh lymphocyte cultures inhibits proliferative and cytotoxic immune responses to the priming alloantigens while sparing responses to third-party stimulator cells. Notch activation in the presence of alloantigen-presenting cells may therefore be a means of inducing specific regulatory T cells while preserving other T-cell functionality. 相似文献
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Concolino P Mello E Patrosso MC Penco S Zuppi C Capoluongo E 《Metabolism: clinical and experimental》2012,61(4):519-524
More than 90% of all cases of congenital adrenal hyperplasia (CAH) result from steroid 21-hydroxylase gene (CYP21A2) mutations. The CYP21A2 gene is located in the human leukocyte antigen (HLA) class III region on the short arm of chromosome 6p21.3, along with an inactive pseudogene, CYP21A1P, that is 98% homologous in its coding sequence with CYP21A2. Most CYP21A2 mutations result from intergenic recombinations between CYP21A2 and the closely linked CYP21A1P pseudogene. Rare mutations not generated by gene conversion account for only 5% to 10% of 21-hydroxylase deficiency alleles. However, detection of these rare and spontaneous mutations has continued to expand worldwide. We identified 2 novel CYP21A2 missense mutations (p.H282N and p.Y191H) in 2 Italian patients with simple-virilizing and nonclassic CAH forms. Functional analysis of these CYP21A2 mutations was performed. Functional in vitro assay for mutagenized CYP21A2 enzymes was performed in transiently transfected mammalian cells to test the residual enzyme activity and the apparent kinetic values. The residual activities obtained allowed us to classify the p.H282N and p.Y191H variants as simple-virilizing and nonclassic CAH associated mutations, respectively. These results correlate with the rate of severity of the patients' disease. This finding provides a further contribution for assisting in the diagnosis of CAH patients. 相似文献
25.
Dr. Gennaro D'amico MD Alberto Morabito MS Luigi Pagliaro MD Ettore Marubini MD The Liver Study Group of “V. Cervello” Hospital 《Digestive diseases and sciences》1986,31(5):468-475
Six-year survival of cirrhosis was assessed in a series of 1155 consecutive patients (751 men, 404 women). Among the men, 33% were alcoholics and 18% were HBsAg positive; corresponding figures for the women were 15% and 6%, respectively. Features of decompensation at first presentation were observed in 63% of the patients. Six-year survival was 54% in compensated and 21% in decompensated patients. No significant differences in survival were found between alcoholics and nonalcoholics. Leading causes of death were liver failure (49%), hepatocellular carcinoma (22%), and bleeding (13%). The prognostic role of 21 variables was evaluated separately in compensated and decompensated patients by the Cox's regression model. The following variables were found to be significant predictors of death risk in compensated patients: male sex, HBsAg positivity, age, prothrombin time prolongation, and esophageal varices. In decompensated disease the significant indicators of death risk were: hepatocellular carcinoma, encephalopathy, hemorrhage, SGOT, esophageal varices, gamma globulins, prothrombin time prolongation, continued abuse of alcohol, HBsAg positivity, gamma glutamyl transpeptidase, and cholinesterase. A simple prognostic index based upon the relative risk coefficient of the significant variables is suggested.Members of the Liver Study Group are: Maria Caltagirone, Gabriella Filippazzo, Giovanni Gatto, Gandolfo Giannuoli, Silvio Margin, Guiseppe Malizia, Lorenzo Maniaci, Maria Pia Marcenó, Alberto Maringhini, Rocco Micciolo, Salvatore Orsini, Fabio Pace, Ugo Palazzo, Linda Pasta, Giuseppina Russo, Rosa Giovanna Simonetti, Mario Spinello, Mario Traina, Mario Valenza, Maria Vinci, Giovanni Vizzini. 相似文献
26.
Ettore Vulcano Jonathan T. Deland Scott J. Ellis 《Current reviews in musculoskeletal medicine》2013,6(4):294-303
Adult acquired flatfoot deformity (AAFD), embraces a wide spectrum of deformities. AAFD is a complex pathology consisting both of posterior tibial tendon insufficiency and failure of the capsular and ligamentous structures of the foot. Each patient presents with characteristic deformities across the involved joints, requiring individualized treatment. Early stages may respond well to aggressive conservative management, yet more severe AAFD necessitates prompt surgical therapy to halt the progression of the disease to stages requiring more complex procedures. We present the most current diagnostic and therapeutic approaches to AAFD, based on the most pertinent literature and our own experience and investigations. 相似文献
27.
Endograft infection after emergency endovascular aortic repair (EVAR) procedure has received less attention than other complications, and usually occurs soon after endograft positioning. Consequently, clear guidelines for the prevention and treatment of endograft infection have yet to come. We report a case of an 85‐year‐old patient treated with an emergency EVAR procedure for a fissured abdominal aortic aneurysm, whose immediate follow up was complicated by a prolonged upper gastrointestinal occlusion. Six months, later he developed an endograft infection due to intestinal flora. After exclusion of all other possible causes, bacterial translocation from the bowel appeared the only plausible mechanism. This case highlights the importance of the gastrointestinal tract as a potential source of endograft infection, and suggests how a clinical condition representing potential reservoir of infection should be managed properly. 相似文献
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