Measurement of lymphocyte activation by a chromatin topo-optical reaction

Summary A rapid inexpensive method is presented for detecting peripheral blood lymphocyte chromatin activation by the neutral red topo-optical reaction, which causes strong and easily measurable birefringence in the lymphocyte nuclei. This reaction can be enhanced by fixing the cells with 150 mM/l NaCl in 70% ethanol and/or by treating the unfixed cellular suspensions with 0.2 M/l HCl to remove histones. In histone-removed preparations, 30 min DNase I treatment almost completely abolished the birefringent reaction, whereas RNase treatment resulted in only 18% loss.Chromatin activation induced by enzyme inhibition increased chromatin birefringence significantly. The same phenomenon could be induced in sensitive subjects' lymphocytes by specific antigens or haptens much more rapidly. The monocytes were not activated to a significant extent. In non-sensitive subjects different kinetics of antigen or hapten-dependent activation and no cytotoxic effects have been observed. Depletion of T-lymphocytes in vivo in SLE patients or by in vitro treatment with 0.5 mM/l KCN as well as with 0.02% trypsin has caused a significant drop in the mean chromatin birefringence. The effect of trypsin was reversible.     

Organization of nucleoli and nuclear bodies in osmotically stimulated supraoptic neurons of the rat

This study has analyzed variations in the number of nucleoli and nuclear bodies, as well as in their ultrastructural and cytochemical organization, after the osmotically induced activation of supraoptic nucleus (SON) neurons of the rat. The number of nucleoli and nuclear bodies and also the nucleolar size were determined on smear preparations of previously block-impregnated SON. The mean number of nucleoli per cell was 1.35 +/- 0.6 (mean +/- SDM) in control rats. No significant variations in this value were registered either in dehydrated or rehydrated rats. The mean nucleolar volume and the total nucleolar volume per cell showed a significant increase in dehydrated rats with respect to the controls, whereas these two parameters tended to return to control values in rats rehydrated after dehydration. The mean number of nuclear bodies per cell increased significantly from 0.56 +/- 0.50 (mean +/- SDM) in control rats to 1.54 +/- 1.1 after 6 days of dehydration. By electron microscopy, SON neurons displayed a reticulated nucleolar configuration. After the osmotically induced neuronal activation, there was an increase in the proportion of the total nucleolar area occupied by the granular component, and also a reduction in the mean fibrillar-center area. The most characteristic nucleolar features in rehydrated rats were the tendency for the granular component to be segregated and the occurrence of intranucleolar vacuoles. Ultrastructural cytochemistry with a specific silver method revealed a selective silver reaction on the coiled threads of the nuclear bodies--identified as "coiled bodies"--and on the nucleolar fibrillar components in all animal groups studied. Since nucleoli play a major role in ribosome biogenesis, a relationship between these nucleolar changes and the level of cellular activity of SON neurons is proposed. Furthermore, the response of nuclear "coiled bodies" to neuronal activation suggests their participation in the processing and transport of rRNA precursors.     

Mutagenicity studies with praziquantel,a new anthelmintic drug: Tissue-, host-, and urine-mediated mutagenicity assays

Praziquantel, a new anthelmintic drug with activity against all species of schistosomes pathogenic to man, and against a wide range of Cestodes, was tested for mutagenic potential. For the detection of both base substitutions and frameshift mutations, Salmonella typhimurium TA 100 and TA 98 were used as tester strains. Using the plate assay with and without added S-9, host-mediated assay and urine-mediated assay without and after incubation with -glucuronidase/arylsulfatase, no mutagenic activity could be detected.     

人结直肠癌平滑肌组织毒蕈碱受体特性的变化

随着受体理论和研究技术的发展 ,人们开始从受体的变化去探寻疾病发生和发展的根源 ,并从受体水平诊治疾病。最近人们发现ＭＡＣｈ Ｒ与肿瘤之间关系密切。一方面 ,ＭＡＣｈ Ｒ过度活化可导致细胞增殖、恶性转化及肿瘤发生[1] ;另一方面 ,在肿瘤状态下ＭＡＣｈ Ｒ的特性也发生变化。本文主要探讨肿瘤状态下ＭＡＣｈ Ｒ特性的变化。1　材料与方法1.1　临床资料　结直肠癌病人 10例 ,男 6例 ,女 4例。中国医科大学附属第一医院肿瘤科提供。1.2　标本采集　结直肠癌患者手术切除的标本 ,分别取癌、癌旁及正常组织各一块。癌旁组织取距癌灶约 2…     

亚硝基谷胱甘肽对大鼠肝微粒体谷胱甘肽转移酶的激活及机制

目的　探索一氧化氮供体亚硝基谷胱甘肽(GSNO)能否在体外通过S 亚硝酰化机制激活大鼠肝微粒体谷胱甘肽转移酶 (mGST)。方法　微粒体粗提物与GSNO体外共孵育 ,测定mGST催化动力学改变 ,结合N 乙基马来酰亚胺 (NEM )再激活实验和二巯基苏醇 (DTT)逆转实验 ,以及酶蛋白游离巯基和酶S 亚硝酰化蛋白的改变 ,研究酶的激活机制。结果　GSNO在 0 .12 5～ 2mmol·L- 1浓度范围内呈浓度和时间 (3～ 15min)依赖性地激活mGST ,NEM对酶的再激活效应消失 ,DTT可以逆转上述激活作用 ,同时酶蛋白游离巯基浓度依赖性减少 ,而S 亚硝酰化蛋白浓度依赖性增多。结论　GSNO体外可激活大鼠肝mGST ,激活机制可能与mGST第 4 9位半胱氨酸 (Cys4 9)的巯基被亚硝酰化形成S 亚硝基硫醇结构有关。     

Plasmapheresis-related hypotension

Hypotension is an uncommon complication of procedures involving extracorporeal circulation, including plasmapheresis. From November 1993 to March 1999, we treated 139 patients who underwent a total of 1,137 sessions of double filtration plasmapheresis (DFP). Hypotension was defined as a systolic blood pressure (BP) < 80 mm Hg or any decrease of systolic BP with systemic reactions. A total of 17 (1.5%) episodes of hypotension were documented in 15 patients during the study period. Hypotensive episodes occurred in 2.3% of patients with inflammatory neuropathy, 1.2% of patients with myasthenia gravis, and 1.2% of patients with all other medical diseases. Involvement of the autonomic nerve system (ANS) and a low baseline BP were associated with the occurrence of hypotension. Eight (47%) of 17 episodes were symptomatic and 2 were complicated with seizure. Patients with symptomatic hypotension had a higher level of systolic BP prior to DFP and a larger drop of systolic BP and pulse rate during hypotensive attacks compared to asymptomatic patients. Most hypotensive episodes were resolved briefly after intravenous infusion of saline within 30 min. Eight (47%) of the hypotensive episodes occurred during the first session of DFP treatment. Twelve (71%) of 17 episodes occurred during the last half period of treatment; 6 of them were noted during the terminating stage of DFP. In conclusion, in this series plasmapheresis-related hypotension occurred in 1.5% of DFP sessions and had a higher prevalence in patients with ANS instability and low BP. Extra caution in monitoring BP during DFP therapy is warranted in these vulnerable patients, especially during the termination phase of the first DFP session.     

血小板活化与炎症性肠病

血小板的种系发生提示其在免疫炎症中起重要作用,近年来发现血小板活化与炎症性肠病的活动性密切 相关,活化的血小板可以释放炎症介质,表达介导炎症反应的表面分子,可与白细胞和内皮细胞发生相互作用,这 为抗血小板药物治疗炎症性肠病提供了理论依据。     

脑出血患者血小板CD62p、CD42b表达及血浆血栓素B2、6-酮前列腺素-F1a和血管性假血友病因子水平的变化及其意义

目的 研究脑出血患者血小板CD62p、CD42b表达及血浆血栓素B2(TXB2)、6-酮前列腺素-F1a(6-keto-PGF1a)和血管性假血友病因子(vWF)水平的变化及其意义.方法 对46例高血压脑出血患者(脑出血组)发病后＜3 d、1周、2周及20例高血压患者(对照组),用流式细胞仪检测血小板CD62p、CD42b表达,酶联免疫吸附法检测血浆TXB2、6-keto-PGF1a和vWF的水平,并分析脑出血患者血小板CD62p、CD42b表达与血浆vWF水平的相关性.结果 在发病后＜3 d、1周及2周,脑出血组血小板CD62p表达和血浆TXB2、vWF水平及TXB2/6-keto-PGF1a(T/K)比值均明显高于对照组(均P＜0.01).血小板CD42b表达和血浆6-keto-PGF1a水平均明显低于对照组(均P＜0.01).脑出血患者血小板CD62p表达与血浆vWF水平呈正相关(r=0.56,P＜0.01),血小板CD42b表达与血浆vWF水平呈负相关(r=-0.60,P＜0.01).结论 脑出血患者出现血小板CD62p表达和血浆TXB2、vWF水平升高,血小板CD42b表达和血浆6-keto-PGF1a水平降低.提示脑出血后有明显血管内皮功能障碍及血小板活化.