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61.
The 14q+ chromosome in pre-B-ALL   总被引:2,自引:0,他引:2  
Kaneko  Y; Rowley  JD; Check  I; Variakojis  D; Moohr  JW 《Blood》1980,56(5):782-785
A child who had acute lymphoblastic leukemia (ALL) associated with an 8;14 chromosome translocation and with a pre-B phenotype is described. The leukemic cells were determined to be pre-B-cells on the basis of intracytoplasmic mu-chain immunoglobulin (cIgM+) and the common-ALL antigen, lack of receptors for sheep erythrocytes, and lack of surface immunoglobulin. The 8;14 translocation is frequently found in patients with Burkitt's lymphoma and in most patients with B-cell ALL and is known to carry a poor prognosis. Thus far, no karyotypes have been reported for patients with pre-B-ALL. The present case indicates that a 14q+ chromosome may provide a proliferative advantage not only to cells with a B-cell phenotype, but also to pre-B-cells. The short survival of our patient also suggests that the 14q+ abnormality and the pre-B phenotype may signal a poor prognosis.  相似文献   
62.
Samples from prospectively followed recipients, their respective donors, and a cohort of random donors were used to evaluate the specificity and efficacy of a recombinant immunoblot assay (RIBA) as an adjunct to anti-hepatitis C virus (HCV) testing by enzyme immunoassay (EIA). RIBA reacted (RIBA+) in 100 percent of patients who developed hepatitis associated with anti-HCV seroconversion documented by EIA and in 100 percent of the EIA-positive (EIA+) donors implicated in these cases. In contrast, RIBA reacted in none of 10 recipients who were EIA+ but did not develop hepatitis, in none of 7 EIA+ patients with hepatitis B or cytomegalovirus infection, in 33 percent of EIA+ donors who were not implicated in hepatitis transmission, and in 37 percent of EIA+ random donors. Hence, the vast majority of EIA+ individuals who have ancillary evidence of HCV infection react on RIBA, whereas the majority of EIA+ individuals in low-risk settings do not react (RIBA-negative, or RIBA-). There was a strong association between RIBA reactivity and the presence of a surrogate marker (elevated alanine aminotransferase [ALT] and/or antibody to hepatitis B core antigen); 43 percent of RIBA+ implicated donors had a surrogate marker as compared to none of 14 EIA+, RIBA- donors. Among EIA+ random donors, 77 percent of those with a surrogate marker were RIBA+, as compared with 29 percent of those without a surrogate marker. In addition, in EIA+ donors, RIBA reactivity correlated with the extent of ALT elevation; 86 percent of those with an ALT greater than 135 IU per L were RIBA+ compared with 18 percent of those with an ALT less than 30 IU per L.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
63.
Dessypris  EN; Redline  S; Harris  JW; Krantz  SB 《Blood》1985,65(4):789-794
The pathogenesis of diphenylhydantoin-induced pure red cell aplasia was investigated in the case of a 32-year-old man who developed pure red cell aplasia while he was under treatment with diphenylhydantoin. The patient's serum IgG purified from serum drawn at the time of diagnosis suppressed normal allogeneic marrow colony-forming (CFU-E) and burst- forming (BFU-E) and autologous blood BFU-E growth in vitro only in the presence of diphenylhydantoin. This IgG-diphenylhydantoin complex had no effect on CFU-GM growth in vitro. Normal IgG or patient's IgG purified from serum drawn after the remission of red cell aplasia had no effect on erythroid colony formation in vitro in the presence of diphenylhydantoin. The IgG-diphenylhydantoin complex exerted no direct cytotoxic effect on normal marrow erythroblasts, CFU-E, and BFU-E, nor did it interfere with the action of erythropoietin on marrow erythroblasts. These studies suggest that diphenylhydantoin-induced red cell aplasia is immunologically mediated through an IgG inhibitor, which requires the presence of the drug to suppress erythroid colony formation in vitro. This inhibitor seems to exert its effect on erythroid progenitors at or beyond the stage of differentiation of CFU- E, but not on erythroblasts.  相似文献   
64.
BACKGROUND & AIMS: We have recently documented the efficacy of a highly concentrated probiotic preparation (VSL#3) in the prevention of flare-up in patients with chronic pouchitis. The aim of this study was to compare probiotic therapy with VSL#3 versus placebo in the ability to prevent the onset of acute pouchitis during the first year after ileal pouch-anal anastomosis. METHODS: Forty consecutive patients who underwent ileal pouch-anal anastomosis for ulcerative colitis were randomized to receive either VSL#3 (1 packet containing 900 billion bacteria/day) (n = 20) or an identical placebo (n = 20) immediately after ileostomy closure for 1 year. The patients were assessed clinically, endoscopically, and histologically after 1, 3, 6, 9, and 12 months. Health-related quality of life was assessed using the Inflammatory Bowel Disease Questionnaire. RESULTS: Two of the 20 patients (10%) treated with VSL#3 had an episode of acute pouchitis compared with 8 of the 20 patients (40%) treated with placebo (log-rank test, z = 2.273; P < 0.05). Treatment with VSL#3 determined a significant improvement in Inflammatory Bowel Disease Questionnaire score, whereas this was not the case with placebo. CONCLUSIONS: Treatment with VSL#3 is effective in the prevention of the onset of acute pouchitis and improves quality of life of patients with ileal pouch-anal anastomosis.  相似文献   
65.
目的:分析壳聚糖-DNA超微颗粒在关节内的转基因效应。方法:实验于2005-09/2006-06在上海交通大学医学院健康科学研究所骨科细胞与分子生物学实验室完成。实验材料:①模型制备:采用切断内侧副韧带,切除内侧半月板的方法制备骨关节炎兔模型。②基因产品:白细胞介素(interleukin,IL)1Ra基因、IL-10基因。实验分组:15只新西兰兔按随机数字表法分为3组:①空载体对照组(n=3),造模后5d两侧膝关节关节腔注射400μL壳聚糖-PcDNA3.1溶液,共3次,每48h1次。②IL-1Ra基因治疗组和IL-10基因治疗组,每组6只,造模后5d对照侧膝关节关节腔分别注射20μg裸DNA(PcDNA3.1-IL-1Ra或PcDNA3.1-IL-10),实验侧膝关节关节腔注射400μL壳聚糖-DNA超微颗粒(含20μgIL-1Ra或IL-10),注射次数及间隔时间同空载体对照组。实验评估:①采用酶联免疫吸附分析及免疫组织化学检测IL-1Ra和IL-10基因的表达和分布。②苏木精-伊红染色和甲苯胺蓝染色观察骨关节炎软骨组织学变化。结果:纳入新西兰兔15只,均进入结果分析。①IL-1Ra和IL-10基因在关节滑液中的表达:空载体对照组及IL-1Ra基因治疗组对照侧膝关节滑液中未检测到IL-1Ra表达,实验侧于第1次基因注射后7,14d检测到IL-1Ra表达。IL-10基因治疗组对照侧和实验侧均未检测到IL-10表达。②IL-1Ra基因在兔膝关节的分布:IL-1Ra基因治疗组兔软骨表层和中间层部分细胞内表达IL-1Ra,至少持续到第1次基因注射后14d。在滑膜组织中未观察到明显的IL-1Ra表达。③兔骨关节炎软骨组织学变化:空载体对照组呈早期骨性关节炎的典型性改变。苏木精-伊红染色显示软骨细胞坏死,蛋白多糖甲苯胺蓝染色不均一,软骨表层和中间层大部分区域失染,软骨细胞簇聚区域其周围深染。IL-1Ra基因治疗组在软骨损坏方面明显减轻,甲苯胺蓝部分失染。结论:①壳聚糖-DNA超微颗粒的转染效率与基因产品有关。②将IL-1Ra用关节腔直接注射壳聚糖-DNA超微颗粒的方法直接转移入关节腔能一定程度上减轻骨性关节炎的进程。  相似文献   
66.
目的:在前期微囊化基因工程细胞制备平台的基础上,构建分泌型人肿瘤坏死因子α的真核表达载体PSNAV2.0-TNFα重组质粒,并鉴定其蛋白的体外瞬时表达,为进一步利用该基因进行微囊化细胞移植治疗和改善疾病奠定基础。方法:实验于2006-06/2007-05在解放军总医院老年医学研究所细胞生物学实验室完成。①以含有人肿瘤坏死因子αcDNA序列的质粒为模板,通过PCR扩增获得人肿瘤坏死因子α基因片段;将其定向插入真核表达载体PSNAV2.0中,获得重组质粒PSNAV2.0-TNFα。采用SalⅠ和EcoRⅠ双酶切法、PCR法及插入片段序列测定法鉴定该质粒。②利用阳离子脂质体介导法,将其转染到人胚胎肾细胞HEK-293细胞中,构建可持续分泌人肿瘤坏死因子α的基因工程细胞,采用RT-PCR法和Western blot法检测转染细胞培养上清液中人肿瘤坏死因子蛋白的体外瞬时表达。结果:①通过SalⅠ和EcoRⅠ双酶切、PCR及测序鉴定证明:在HEK-293中插入片段正确。②采用RT-PCR和Western blot法检测表明HEK-293细胞培养上清中有人肿瘤坏死因子α蛋白,Mr17000。结论:成功构建了重组质粒PSNAV2.0-TNFα真核表达载体,转染HEK-293细胞后可有效分泌人肿瘤坏死因子α蛋白,并能分泌到细胞外。  相似文献   
67.
肠息肉发生的细胞和分子生物学研究进展   总被引:1,自引:0,他引:1  
肠息肉是一类从黏膜表面突出到肠腔内的隆起状病变的临床诊断.在最近的研究中陆续证实,其发生和发展的原因和机制,是由于Bmprla,APC,SMAD4,PTEN,STK11等基强突变而使各种细胞信号分子通过影响BMP信号通路,PTEN信号通路及Wnt信号通路所组成的生长信号调控网络,造成β-catenin在肠干细胞中的过度积聚,使得肠干细胞功能紊乱,导致其自我更新、克隆增殖、分化和凋亡失去平衡的结果.  相似文献   
68.
Narcolepsy with cataplexy is a rare disease with an estimated prevalence of 0.02% in European populations. Narcolepsy shares many features of rare disorders, in particular the lack of awareness of the disease with serious consequences for healthcare supply. Similar to other rare diseases, only a few European countries have registered narcolepsy cases in databases of the International Classification of Diseases or in registries of the European health authorities. A promising approach to identify disease‐specific adverse health effects and needs in healthcare delivery in the field of rare diseases is to establish a distributed expert network. A first and important step is to create a database that allows collection, storage and dissemination of data on narcolepsy in a comprehensive and systematic way. Here, the first prospective web‐based European narcolepsy database hosted by the European Narcolepsy Network is introduced. The database structure, standardization of data acquisition and quality control procedures are described, and an overview provided of the first 1079 patients from 18 European specialized centres. Due to its standardization this continuously increasing data pool is most promising to provide a better insight into many unsolved aspects of narcolepsy and related disorders, including clear phenotype characterization of subtypes of narcolepsy, more precise epidemiological data and knowledge on the natural history of narcolepsy, expectations about treatment effects, identification of post‐marketing medication side‐effects, and will contribute to improve clinical trial designs and provide facilities to further develop phase III trials.  相似文献   
69.
BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a major health problem with an estimated prevalence of 10-15% among smokers. The incidence of moderate COPD, as defined by the Global Initiative for Chronic Obstructive Lung Disease (GOLD), is largely unknown. AIM: To determine the cumulative incidence of moderate COPD (forced expiratory volume in 1 second/forced vital capacity ratio [FEV1/FVC] <0.7 and FEV1 <80% predicted) and its association with patient characteristics in a cohort of male smokers. DESIGN: Prospective cohort study. SETTING: The city of IJsselstein, a small town in the Netherlands. METHOD: Smokers aged 40-65 years who were registered with local GPs, participated in a study to identify undetected COPD. Baseline measurements were taken in 1998 of 399 smokers with normal spirometry (n = 292) or mild COPD (FEV1/FVC <0.7 and FEV1 >or=80% predicted, n = 107) and follow-up measurements were conducted in 2003. RESULTS: After a mean follow-up of 5.2 years, 33 participants developed moderate COPD (GOLD II). This showed an estimated cumulative incidence of 8.3% (95% CI = 5.8 to 11.4) and a mean annual incidence of 1.6%. No participant developed severe airflow obstruction. The risk of developing moderate COPD in smokers with baseline mild COPD (GOLD I) was five times higher than in those with baseline normal spirometry (one in five versus one in 25). CONCLUSIONS: In a cohort of middle-aged male smokers, the estimated cumulative incidence of moderate COPD (GOLD II) over 5 years was relatively high (8.3%). Age, childhood smoking, cough, and one or more GP contacts for lower respiratory tract problems were independently associated with incident moderate COPD.  相似文献   
70.
The present study was undertaken to assess the temporal association between the profiles of serum concentrations of oestradiol-17beta, progesterone, chorionic gonadotrophin (CG) and relaxin in pregnancies established naturally, and after embryo transfer, as well as in failed pregnancies in rhesus monkeys. In naturally mated cycles (group 1) a conception rate of 75% was obtained. In group 1, the mean day of CG detection in serum was 11.5 +/- 1.9 day post-ovulation, and for relaxin, 9.0 +/- 2.5 day post-ovulation. In group 2, embryo transfer to synchronous, non-mated surrogate recipients was performed; seven embryo transfer cycles yielded three pregnancies which were allowed to continue to term and normal infants were delivered. In embryo transfer cycles the mean day of CG detection was 14.8 +/- 1.8 day post- ovulation, and for relaxin, 11.4 +/- 2.6 day post-ovulation. A delay of about 3 days was observed in the appearance in circulation of CG (P < 0.05) and also of relaxin (P < 0.05) between natural mated and embryo transfer conception cycles. Significant differences (P < 0.05 for progesterone and P < 0.03 for oestradiol) were obtained for the areas under the curves for progesterone and oestradiol between days 12 and 16 in conception cycles compared with failed pregnancies. These data provide the first observation of the normal hormonal signals associated with maternal recognition of transferred embryos during the peri- implantation period, and suggest that the use of such an experimental primate embryo transfer model may help to elucidate components of maternal and embryonic signal-response mechanisms during embryo implantation.   相似文献   
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