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991.
OBJECTIVE: To report the outcome of gene therapy in an infant with X-linked severe combined immunodeficiency (SCID-X1), which typically causes a lack of T and natural killer (NK) cells. DESIGN AND SETTING: Ex-vivo culture and gene transfer procedures were performed at The Children's Hospital at Westmead, Sydney, NSW, in March 2002. Follow-up to March 2005 (36 months) is available. PATIENT: A 9-month-old male infant with confirmed SCID-X1 (including complete absence of T cells) with an NK+ phenotype (a less common variant of SCID-X1), and no HLA-identical sibling donor available for conventional bone marrow transplantation. PROCEDURE: CD34+ haemopoietic progenitor cells were isolated from harvested bone marrow and cultured with cytokines to stimulate cellular replication. Cells were then genetically modified by exposure to a retrovirus vector encoding human gamma c (the common gamma chain of several interleukin receptors; mutations affecting the gamma c gene cause SCID-X1). Gene-modified cells (equivalent to 1.3 x 10(6) CD34+/gamma c+ cells/kg) were returned to the infant via a central line. RESULTS: T cells were observed in peripheral blood 75 days after treatment, and levels increased rapidly to 0.46 x 10(9) CD3+ cells/L at 5 months. Within 2 weeks of the appearance of T cells, there was a distinct clinical improvement, with early weight gain and clearance of rotavirus from the gut. However, T-cell levels did not reach the reference range, and immune reconstitution remained incomplete. The infant failed to thrive and developed weakness, hypertonia and hyperreflexia in the legs, possibly the result of immune dysregulation. He went on to receive a bone marrow transplant from a matched unrelated donor 26 months after gene therapy. CONCLUSIONS: This is the first occasion that gene therapy has been used to treat a genetic disease in Australia. Only partial immunological reconstitution was achieved, most likely because of the relatively low dose of gene-corrected CD34+ cells re-infused, although viral infection during the early phase of T-cell reconstitution and the infant's NK+ phenotype may also have exerted an effect.  相似文献   
992.
Rat testis transplantation with a segment of donor abdominal aorta end-to-side anastomosed to recipient‘s abdominal aorta was first reported by Lee. But thrombus was formed in the donor abdominal aorta segment. Goldsein and Lee improved this technique using end-to-side anastomosis of an aortic patch with the testicular artery to the recipient‘s aorta and the testicular vein was anastomosed to the vena cava of the recipient. With this method,  相似文献   
993.
Quercetin is a bioactive flavonoid widely used as a health supplement. Being sparingly soluble and chemically unstable in aqueous intestinal fluids, quercetin is poorly absorbed orally. This study aimed to investigate the effects of three beta-cyclodextrins, namely, unsubstituted beta-cyclodextrin (beta-CD), hydroxypropyl-beta-cyclodextrin (HP-beta-CD), and sulfobutyl ether beta-cyclodextrin (SBE-beta-CD) on the chemical stability and water solubility of quercetin, and to elucidate the complexation mechanisms of these beta-CDs with quercetin. Quercetin-beta-CD complexes in solution were characterized by stability assessment, phase solubility measurements, and 1H-nuclear magnetic resonance (NMR) spectroscopy. Molecular modeling was used to help establish the mode of interaction of the beta-CDs with quercetin. Solubility enhancements of quercetin obtained with the three beta-CDs followed the rank order: SBE-beta-CD > HP-beta-CD > beta-CD. The stability of quercetin at alkaline pHs also showed substantial improvement. NMR spectroscopic analysis suggested that the B-ring, C-ring, and part of the A-ring of quercetin display favorable interaction with the hydrophobic cavity of the beta-CDs, which was confirmed by molecular dynamics (MD) simulations using a solvated model of the quercetin-beta-CD complex. An inclusion complex model has been established for explaining the observed augmentation of solubility and stability of quercetin in water by beta-CDs.  相似文献   
994.
Cytotoxic activities of new jadomycin derivatives   总被引:1,自引:0,他引:1  
Cytotoxic activities of jadomycin B and five new jadomycin derivatives against four cancer cell lines (HepG2, IM-9, IM-9/Bcl-2 and H460) were evaluated. Jadomycin S was most potent against HepG2, IM-9 and IM-9/Bcl-2 while jadomycin F was most potent against H460. Their potencies correlated with the degrees of apoptosis induced. Structure-activity-relationship analyses clearly demonstrate that the side chains of the oxazolone ring derived from the incorporated amino acids make a significant impact on biological activity. Therefore, jadomycin offers an ideal scaffold to manipulate structure and could be exploited to make many novel bioactive compounds with altered activities.  相似文献   
995.
AIM: We earlier showed in rats that fascial repair with Pelvicol, a porcine dermal collagen implant, was associated with a lesser inflammatory response but lower tensile strength in the early postoperative period as compared to Prolene. Herein we wanted to evaluate whether creation of pores in Pelvicol, facilitating ingrowth of fibrous tissue and vessels, would result in a higher tensile strength at d30 without compromising longer term results. METHODS: First tensile strength of Pelvicol modified with different pore sizes was evaluated ex vivo. In a second step, Pelvicol implants with pores were used to cover full-thickness abdominal wall defects in 36 rats. Implants were either Pelvicol (non-porous) or with pores of Phi : 0.7, 1.2, or 2.0 mm (n=6 each). Animals were sacrificed on d30 and 90 to evaluate the presence of herniation, infection, adhesions, change in thickness and tensile strength. Histopathology was performed to assess inflammatory response and collagen deposition. Data were compared to available data on Prolene implanted animals at same time points. RESULTS: Pelvicol with pore diameter of 2.5 mm was significantly weaker ex vivo. Animals repaired with non-porous material did develop seroma (2/6) or clinical infection (1/6) whereas none in the other groups did. There was a trend for increasing tensile strength at 30 d with increasing pore diameter, being significant in the 2.0-mm pore size group. This difference disappeared by 90 d, where all materials were equally strong as Prolene. The foreign body reaction was less intense in a pore-size dependent manner, with more abundant neo-vascularization and collagen deposition passing through the pores. CONCLUSION: Creation of pores in Pelvicol promotes neo-vascularization, collagen deposition, and fibrous tissue ingrowth, and at pore size 2.0 mm tensile strength was increased at d30 whereafter all materials had comparable strength.  相似文献   
996.
肝细胞癌肝移植89例预后分析   总被引:10,自引:0,他引:10  
目的 总结肝细胞癌(HCC)肝移植临床经验,探讨HCC肝移植的预后影响因素。方法 应用单因素分析和逐步Logistic回归多因素分析方法,回顾性分析自1999年1月至2003年12月我单位施行的89例HCC肝移植患者的生存情况及各项临床病理指标对预后的影响。结果 移植后6个月、1年和2年累积生存率分别为81. 8%、55. 3%和43 .7%, 6个月、1年和2年无瘤生存率分别为62 .4%、35. 6%和24 .9%;随访期间肿瘤转移复发的总发生率为52 8%;Log rank检验结果显示,影响HCC患者肝移植术后累积生存率的因素为门静脉主干或分支癌栓形成(PVTT) (χ2 =15 14,P=0. 0001)、肿瘤大小(χ2 =15. 05,P=0 .0001 )、肝硬化背景(χ2 =6 14,P=0 .0132 )、术前甲胎蛋白(AFP)水平(χ2 =5 .82,P=0. 0159)和组织学分级(χ2 =4. 61,P=0 .0319);影响无瘤生存率的因素包括PVTT(χ2 =26 .30,P<0. 0001 )、肿瘤大小(χ2 =25 .25,P<0 0001 )、AFP水平(χ2 =14. 83,P=0 .0001)、组织学分级(χ2 =12 54,P=0. 0004 )、肿瘤分布(χ2 =12 73,P=0. 0004 )、肿瘤数目(χ2 =9 81,P=0 0017)以及肝硬化背景(χ2 =9 .76,P=0 .0018)。多因素分析结果显示,与累积生存率显著相关的因素是PVTT(RR=4. 721,P=0. 001 )、年龄(RR=3. 282,P=0 .007 )和组织学分级(RR=2. 368,P=0.  相似文献   
997.
Study objective: To asses the association between alcohol consumption and the risk of colorectal cancer (CRC) in the Chinese population. Design: A population-based prospective cohort study was initiated from the colorectal cancer screening population in Jiashan County in 1989–1990. The drinking habits of individuals were investigated with demographic information. Setting: A cohort study was followed-up from 1st May 1990 to 1st January 2001 and censored at the date of diagnosis of CRC, at death from any causes, or at 1st January 2001, whichever came first, and the person-time was computed. Participants: Two hundred and forty two CRC patients were diagnosed during the study period and 64,100 individuals finished the follow-up. Results: The distribution of sex, smoking status, occupation, education level and marital status were all significantly different among different drinking habits at baseline. When the above factors were adjusted, no significant association was observed between alcohol consumption and the risk of CRC. Exclusion of individuals diagnosed cancer less than 1 year after the examination date did not alter the strength of an alcohol–CRC relationship. Further analysis in sex strata also did not show a significant relationship. Conclusions: Alcohol drinking may not be associated with a higher risk of CRC in the Chinese population.This revised was published online in April 2005. In the previous version the article category was missing.  相似文献   
998.
Summary Glioblastomas are among the most difficult neoplasms to treat with continued poor prognosis for long-term survival. Glioblastomas have developed effective mechanisms to resist chemotherapy including levels anti-apoptotic proteins, Bcl-xL and Bcl-2. Chemotherapy agents that promote down-regulation of Bcl-xL and Bcl-2 may enhance sensitivity to chemotherapy in glioblastomas. The ability of the synthetic retinoid N-(4-hydroxyphenyl) retinamide to modulate these anti-apoptotic proteins and to enhance apoptosis and chemotherapy was examined in glioblastoma cells. Expression of Bcl-2 family member proteins Bcl-xL and Bcl-2 were assessed in glioblastomas from three cell lines including U87, U251, and U138. Cells were treated with either retinamide alone or in combination with the chemotherapy agent, BCNU. The incidence of apoptosis was determined with flow cytometry analysis (FACS). Based on Western blots the levels of Bcl-2 and Bcl-xL were decreased in glioblastoma cells after treatment with retinamide. Retinamide treatment resulted in increased ratios of deamidated verses transamidated levels of Bcl-xL in U87 cells. BCNU chemotherapy combined with retinamide markedly down-regulated levels of both Bcl-xL and Bcl-2 proteins in glioblastoma and enhanced the incidence of apoptosis in U87 cells. These studies demonstrate that modulation of levels of the anti-apoptotic proteins, Bcl-xL and Bcl-2, may enhance the sensitivity of glioblastoma toward chemotherapy.  相似文献   
999.
1000.
Acute myeloid leukemia is characterized by a differentiation block as well as by an increased self-renewal of hematopoietic precursors in the bone marrow. This phenotype is induced by specific acute myeloid leukemia-associated translocations, such as t(15;17) and t(11;17), which involve an identical portion of the retinoic acid receptor alpha (RARalpha) and either the promyelocytic leukemia (PML) or promyelocytic zinc finger (PLZF) genes, respectively. The resulting fusion proteins form high molecular weight complexes and aberrantly bind several histone deacetylase-recruiting nuclear corepressor complexes. The amino-terminal BTB/POZ domain is indispensable for the capacity of PLZF to form high molecular weight complexes. Here, we studied the role of dimerization and binding to histone deacetylase-recruiting nuclear corepressor complexes for the induction of the leukemic phenotype by PLZF/RARalpha and we show that (a) the BTB/POZ domain mediates the oligomerization of PLZF/RARalpha; (b) mutations that inhibit dimerization of PLZF do the same in PLZF/RARalpha; (c) the PLZF/RARalpha-related block of differentiation requires an intact BTB/POZ domain; (d) the mutations interfering with either folding of the BTB/POZ domain or with its charged pocket prevent the self-renewal of PLZF/RARalpha-positive hematopoietic stem cells. Taken together, these data provide evidence that the dimerization capacity and the formation of a functionally charged pocket are indispensable for the PLZF/RARalpha-induced leukemogenesis.  相似文献   
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