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31.
Stong  RC; Uckun  F; Youle  RJ; Kersey  JH; Vallera  DA 《Blood》1985,66(3):627-635
The monoclonal antibodies (MoAb) T101, G3.7, 35.1, and TA-1 were conjugated to intact ricin using a thioether linkage. These MoAb detect, respectively, the CD5[gp67], CD7[p41], CD2[p50], and [gp95, 170] determinants that are found in the vast majority of cases of T cell acute lymphocytic leukemia (T-ALL). The resulting immunotoxins (ITs) and an equimolar mixture of these ITs were evaluated as potential purgative reagents for autologous transplantation in T-ALL. Leukemic cell lines were used to compare the kinetics of protein synthesis inactivation mediated by each IT. The cells were treated with IT in the presence of lactose in order to block the native binding of ricin. The observed rates of protein synthesis inactivation correlated with target antigen expression detected by fluorescence-activated cell sorter analysis. Of the four ITs, T101-ricin (T101-R) exhibited the fastest rate of inactivation, followed in order by G3.7-ricin, TA-1-ricin, and 35.1-ricin. At concentrations greater than 300 ng/mL, a cocktail containing an equimolar amount of all four ITs (referred to as the four- IT cocktail) exhibited kinetics that were as fast or faster than those of T101-R. The long-term cytotoxic effects of individual ITs and the four-IT cocktail were evaluated using a sensitive clonogenic assay. Each IT was specifically cytotoxic and inhibited 1 to 4 logs of clonogenic leukemic cells at doses (300 to 600 ng/mL) that can be used clinically. The four-IT cocktail was highly cytotoxic; a concentration of 300 ng/mL inhibited greater than 4 logs of leukemic cells while sparing the majority of committed (CFU-GM, CFU-E) and pluripotent (CFU- GEMM) hematopoietic stem cells. The determination of both short-term kinetics of protein synthesis inactivation and longer-term inhibition of clonogenic growth allowed new insight into cell killing by IT. Our results suggest that ITs continue to act on clonogenic target cells for a period of three to five days. Interestingly, the four-IT cocktail was not as potent against clonogenic leukemic cells as T101-R alone, although it exhibited kinetics of protein synthesis inhibition that were as fast as those of T101-R alone. This finding suggests that internalized ITs may differ in the length of time they remain active within the cell. Our results also demonstrate the importance of using several different assays to evaluate IT reagents.  相似文献   
32.
Regulation of expression of the human interferon gamma gene.   总被引:14,自引:1,他引:14       下载免费PDF全文
DNA fragments isolated from a genomic clone of human gamma interferon (IFN-gamma) as well as IFN-gamma cDNA were used to map potential regulatory regions of the IFN-gamma gene by DNase I-hypersensitivity analyses. In nuclei from the human T-cell line Jurkat, which can be induced to express the IFN-gamma gene, we observed a strongly hypersensitive site in the first intervening sequence that localized to the only intracistronic repeat element in the gene. DNase I mapping of Jurkat cells was compared to that of several other cell types, including B cells, macrophages, and epithelial cells. The presence of strong intronic hypersensitivity was found only in cells capable of expressing the IFN-gamma gene. No hypersensitivity was found in the 3' regions of the gene. Further, no hypersensitivity was observed when purified genomic DNA from Jurkat was analyzed, suggesting that DNA-protein interactions, and not simply DNA sequence alone, were responsible for DNase I hypersensitivity. The sequence AAGTGTAATTTTTTGAGTTTCTTTT, which is directly in the intronic hypersensitive area of IFN-gamma, is 83% homologous to a nearly identical sequence in the 5' flanking region of the interleukin 2 gene. In interleukin 2, the homologous sequence is about 300 base pairs upstream of that gene's promoter in an area of potential regulatory importance.  相似文献   
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波尔山羊重复超排效果的研究   总被引:8,自引:1,他引:8  
对 2 0只波尔山羊实施两次超排处理。其结果如下 :1.第 1次超排处理时 2 0只供体羊全部发情并进行采卵 ,超排有效率为 10 0 % ;平均排卵数为 2 0 .2 5枚 /只 ,平均采集胚胎数 19.2 5枚 /只 ,平均采集可用胚胎数为 17.3枚 /只 ;第 2次超排处理时有 3只羊推迟发情 ,超排有效率为 85 % ;平均排卵数 19.2 9枚 /只 ,平均采集胚胎数 18.5 3枚 /只 ,平均采集可用胚胎数 17.35枚 /只 ;2 .两次超排所获得的平均可用胚胎数差异不显著(p >0 .0 5 )。  相似文献   
35.
目的:测定二硫代氨基甲酸吡咯烷(PDTC)处理对人肝癌细胞Hep3B凋亡的诱导作用及Cu^2 对这种作用的影响。方法:运用细胞增殖力、膜损伤、DNA片断化、细胞周期DNA含量测定分析PDTC对人肝癌细胞株Hep3B细胞的增殖抑制及凋亡诱导作用及Cu^2 在其中发挥的作用。结果:PDTC处理后,细胞增殖能力显著下降。乳酸脱氢酶(LDH)分析显示细胞膜并没有被破坏,DNA凝胶电泳及细胞周期DNA含量测定发现明显的凋亡特征性DNA片断及亚G1峰,显示细胞增殖能力的降低源于细胞凋亡的发生。低浓度Cu^2 显著加强了PDTC的细胞增殖抑制及凋亡诱导作用,而Cu^2 络合剂Bathocuproine disulfonate(BCS)显著抑制PDTC的两种作用。结论:PDTC铜离子依赖性地抑制人肝癌细胞增殖并诱导细胞凋亡。  相似文献   
36.
目的 评价中心静脉压(CVP)联合全心舒张末容积指数(GEDVI)指导感染性休克患者容量治疗的效果.方法 感染性休克患者23例,性别不煨,年龄18~64岁,休克时间<6h,急性生理和慢性健康状况评分13~31分,采用随机数字表法,将其随机分为2组:CVP指导容量治疗组(Ⅰ组,n=12)和CVP联合GEDVI指导容量治疗组(Ⅱ组,n=11).2组均静脉输注生理盐水和6%羟乙基淀粉200/0.5,晶体液和胶体液的比例为1∶(0.5 ~ 1.0),输注速率800~ 1600 ml/h,容量治疗过程中Ⅰ组维持CVP8~ 12mmHg;Ⅱ组维持CVP>8 mm Hg和GEDVI 600 ~ 750 ml/m2.分别于容量治疗前及容量治疗开始后6h时采集动脉及中心静脉的血样,测定血乳酸浓度和中心静脉血氧饱和度(ScvO2),计算乳酸和ScvO2的变化率.结果 与Ⅰ组比较,Ⅱ组乳酸变化率升高(P<0.05),ScvO2变化率差异无统计学意义(P>0.05).结论 与CVP指导容量治疗比较,CVP联合GEDVI指导感染性休克患者容量治疗时可增加组织灌注,其效果较好.  相似文献   
37.
目的 探讨改良颈腮腺入路在高位咽旁间隙良性肿瘤手术中的应用疗效。 方法 7例咽旁间隙良性肿瘤患者,术前影像学检查提示为高位、肿瘤巨大、哑铃型且边界欠清,采用改良颈腮腺入路术式,解剖辨认面神经总干及颞面干后,于外耳道软骨前方、腮腺的后缘以及颞面干的上方间隙向深部分离至肿瘤上极,剥离子分离并下压肿瘤与下方常规颈部自下而上肿瘤游离会师后,从颌下区取出肿瘤。腮腺浅叶不切除,面神经分支不做过多解剖。 结果 所有患者均一次性完整切除肿瘤;术后病理示多形性腺瘤6例,神经鞘瘤1例;术中出血均少于300 mL;1例患者出现术后同侧眼睑轻度闭合障碍,两周后完全正常;所有患者面容美学保存理想。 结论 对于高位咽旁间隙良性肿瘤采用改良颈腮腺入路术式,不仅可以安全完整地切除肿瘤,同时由于减少了面神经及腮腺浅叶的处置,术后相关神经并发症及腮腺区凹陷性改变的发生率下降。  相似文献   
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Recent experiments in cultured cyst epithelial cells from kidneys of patients with autosomal dominant polycystic kidney disease (ADPKD) have shown that the cystic fibrosis (CF) transmembrane conductance regulator (CFTR) is present in the apical surface of these cells and mediates chloride (Cl-) and fluid secretion in vitro. To determine whether the presence of CF with the expression of mutated CFTR proteins modifies cyst formation in ADPKD, we studied a large family with both inherited diseases. ADPKD in this family is linked to PKD1. The family is composed of 26 members; 11 members with ADPKD, 4 members with CF, and 2 members with both diseases. Renal volumes measured by computerized tomography (CT), calculated creatinine clearances, and other clinical parameters in the family members with ADPKD and CF were compared with those in the family members with ADPKD alone, as well as to a large population of patients with ADPKD. The patients with CF and ADPKD, but not the CF heterozygote carriers with ADPKD, had less severe polycystic kidney and liver disease, as indicated by normal renal function; smaller renal volume, even when corrected for height and body surface area; and the absence of hypertension and liver cysts. These observations suggest that the coexistence of CF may reduce the severity of ADPKD.  相似文献   
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