Pathologic effects of plasma from patients with thrombotic thrombocytopenic purpura on platelets and cultured vascular endothelial cells

The pathologic hallmarks of thrombotic thrombocytopenic purpura (TTP) include endothelial cell proliferation and subendothelial hyalin deposits in the microvasculature leading to symptomatic thrombotic occlusions. Plasma or sera from three consecutive patients with TTP were subjected to multiple analyses to determine whether they induce endothelial injury and/or platelet activation, two pathogenic mechanisms that may account for this disorder. Sera were utilized in a microcytotoxicity assay against cultured human umbilical vein endothelial cells (EC). These cells were assessed ultrastructurally and with immunofluorescence techniques to ascertain the nature of inflicted cell damage. Control plasmas were obtained from healthy volunteers as well as patients with immune complex disease and the adult hemolytic uremic syndrome. In the presence of TTP serum, cell kill of 3H-proline- labeled EC averaged 42% versus 8.6% for control sera. Cytotoxicity induced by an IgG fraction of TTP sera averaged 70% versus 16.8% for control IgG. Removal of IgG by immune precipitation diminished cytotoxicity by 70%. Using indirect immunofluorescence, IgG was detected on EC incubated with TTP serum but not on EC treated with control serum. Ultrastructural changes became apparent within 30 min after exposure of cultured EC to TTP serum. Virtually every cell developed numerous cytoplasmic inclusions rarely seen in EC in the presence of normal serum. Prolonged incubation with the TTP serum led to progressive cytolysis, terminating with complete cytoplasmic and nuclear degeneration. Plasma from all three patients with TTP caused spontaneous aggregation of normal washed platelets as monitored by aggregometry. No spontaneous aggregation occurred in response to control plasmas. These results indicate that the sera of the three TTP patients studied were able to mediate time-dependent immune destruction of human cultured endothelial cells and that their plasmas were capable of causing spontaneous aggregation of normal human platelets in vitro. It would seem likely that these mechanisms are also operative in vivo to produce the endothelial destruction as well as the thrombotic vascular occlusions seen in this disorder.     

Platelet modulation of polymorphonuclear leukocyte shear induced aggregation

A cone and plate viscometer and Coulter Counter were used to study platelet modulation of polymorphonuclear leukocyte (PMNL) aggregation caused by controlled shear stress. As an index of aggregation, the large-particle percentage (LPP) was calculated. This represents the ratio of aggregated cell count to total cell count. PMNL suspensions in buffer (1.0 X 10(7) cells per milliliter, final concentration) did not show any aggregate formation at shear stresses below 150 dynes/cm2 for one minute exposure time (LPP less than 3%). However, there was PMNL aggregation in mixed PMNL and platelet-rich plasma suspensions in this shear stress range. Supernatant plasma from sheared platelets initiated PMNL aggregation at moderate shear stress (150 dynes/cm2 for one minute; LPP, 20.3% +/- 2.5%). In contrast, platelet release factors, such as adenosine diphosphate (2 mumol/L) and serotonin (2 mumol/L) did not cause PMNL aggregation (LPP, 2.9% +/- 1.2% and 3.3% +/- 0.8%, respectively). The use of a cyclo-oxygenase inhibitor (acetylsalicylic acid, 50 mumol/L) did not suppress the aggregation of PMNLs after shear (LPP, 20.1% +/- 2.4%). However, preincubation with nordihydroguaiaretic acid (10 mumol/L), an inhibitor of C-5 and C-12 lipoxygenase, and 6,9- deepoxy-6,9-(phenylimino)-6,8-prostaglandin I1 (U-60257, 10 mumol/L), an inhibitor of C-5 lipoxygenase in human leukocytes, suppressed this aggregation (LPP, 9.1% +/- 2.5% and 10.4% +/- 3.2%, respectively). Also, the formation of lipoxygenase products (5-HETE, 12-HETE, 15-HETE, and LTB4) activated by shear stress was documented by reversed phase- high-performance liquid chromatography (RP-HPLC). These data support the possibility of a cooperation between platelets and leukocytes in shear-induced PMNL aggregation that is dependent on C-12 or C-5 lipoxygenase activity, or both.     

Genetic analysis of human immunodeficiency virus in Abidjan, Ivory Coast reveals predominance of HIV type 1 subtype A and introduction of subtype G

To better understand the molecular epidemiology of HIV genetic diversity in Abidjan, Ivory Coast, we performed a genetic analysis of 170 HIV-1-seropositive specimens representing newly diagnosed tuberculosis patients (n = 143) and women monitored in a mother-to-child transmission cohort study (n = 27). Preliminary screening with RFLP presumptively classified 162 (95.3%) of these as subtype A. The envelope region of 108 specimens was subtyped by sequence analysis: 102 (94.4%) were subtype A, 2 (1.9%) were subtype D, and 4 (3.7%) were subtype G. Subtyping gag and env regions of the genome suggested that five of the six nonsubtype A isolates exhibited a potentially mosaic structure. A comparative phylogenetic analysis of HIV-1 subtype A C2V3 from 27 Ivory Coast and 21 Ugandan sequences revealed a striking clustering among Ivory Coast variants, and an independent segregation from Ugandan subtype A. Despite independent clustering with other subtype A specimens, limited variability of the V3 loop apex was observed; the globally predominant V3 motif, GPGQ, represented 90.1% of the HIV-1 strains. This study demonstrates that clade A is the predominant HIV-1 subtype in HIV-seropositive individuals in Abidjan, Ivory Coast and that these strains are phylogenetically distinct from other subtype A strains observed in East Africa.     

应用OHIP-14评价2种种植系统OHRQoL的差异

目的 研究2种种植系统修复治疗后口腔健康相关生活质量（OHRQoL）的差异,为临床种植系统的选择和治疗效果的评估提供参考。方法 临床收集门诊且符合纳入标准的种植义齿修复患者100例,其中50例A组行安多健（Anthogry）种植系统修复,50例B组行士卓曼（Straumann）种植系统修复。采用口腔健康影响程度量表（OHIP-14）中文版作为测量方法研究2种种植系统修复6个月后患者OHRQoL的得分情况,比较两种种植系统修复后患者的OHRQoL的差异。结果 A组："生理性疼痛"得分最高（P₅₀=3.00）,其次为"心理不适,心理障碍"（P₅₀=2.00）;"吃什么东西都不舒服"最常给牙列缺损患者带来负面影响。B组："生理性疼痛"、"心理不适"、"生理障碍"三者得分最高（P₅₀=2.00）,其次为"心理障碍"（P₅₀=1.5）;"对自己的饮食很不满意"最常给牙列缺损患者带来负面影响。治疗后Anthogry与Straumann量表总得分差异无统计学意义（P>0.05）。结论 2种种植系统均能改善患者口腔健康状况,患者对两种系统的整体主观感受并无明显差异。     

补肺健脾益肾方治疗对老年COPD稳定期患者T淋巴细胞亚群、BODE指数及生活质量的影响

目的:评价补肺健脾益肾方治疗老年慢性阻塞性肺疾病(COPD)稳定期的疗效及对患者外周血T淋巴细胞亚群、BODE指数及生活质量的影响.方法:将80例中医辨证为肺脾肾气虚型COPD稳定期患者随机分组,对照组(40例)仅采取常规西医治疗,而观察组(40例)在常规西医治疗的基础上联合补肺健脾益肾汤,治疗8周后比较临床疗效及患者外周血T淋巴细胞亚群、BODE指数及生活质量的变化.结果:经治疗后观察组BODE指数及BMI积分、FEV1积分、MMRC积分、6MWT积分均较对照组明显减少,差异具有统计学意义(P＜0.05);经治疗后观察组CD3+、CD4+及CD4+/CD8+较对照组明显升高,CD8 +水平较对照组明显降低,差异具有统计学意义(P＜0.05);两组经治疗后肺功能指标FEV1和FEV1/FVC均较治疗前有明显改善,差异具有统计学意义(P＜0.05);两组治疗后SGRQ评分均较治疗前明显降低,但观察组治疗后SGRQ评分明显低于对照组,差异具有统计学意义(P＜0.05).结论:补肺健脾益肾方用于老年COPD稳定期治疗可改善患者肺功能及BODE指数,提高生活质量,增强细胞免疫功能.     

Toxic effect of puromycin on erythrocyte membranes which is unrelated to inhibition of protein synthesis

Exposure of rabbit or human erythrocytes to concentrations of puromycin as low as 7 x 10(-4)M for 2 hr causes damage to the cell membrane, as evidenced by increased susceptibility of the cells to hyposmotic lysis, increased cell rigidity, and ultrastructural changes consistent with severe membrane damage. Puromycin causes a concentration-dependent internalization of the erythrocyte membrane, resulting in vacuolization of the cells, at concentrations between 7 x 10(-4) M and 10(-2) M. Since the erythrocyte does not synthesize protein, the data indicate that puromycin has a direct toxic effect on erythroid cell membranes which is unrelated to its action in inhibiting the synthesis of protein.     

唇腭裂患者AF-BF距及AXB角的测量分析

目的 研究唇腭裂患者AF-BF距和AXB角.方法 选取20例替牙期及30例恒牙期唇腭裂患者拍摄头颅定位侧位X线片,测量其AF-BF距及AXB角与北京市同龄、同性别正常儿童、青少年的AF-BF距及AXB角值进行比较.结果 替牙期和恒牙期唇腭裂患者AF-BF距及AXB角值无性别差异(P > 0.05).新疆地区替牙期和恒牙期唇腭裂患者AF-BF距小于北京市正常儿童、青少年(P < 0.05),而AXB角值差异无统计学意义(P > 0.05).结论 AF-BF距可以作为评价唇腭裂患者上下颌骨间矢状关系的指标之一,但最好进行综合分析.     

不育患者精索静脉曲张手术前后精液质量变化的观察

目的:观察不育患者精索静脉曲张手术前后精液质量的变化,探讨手术的价值。方法:按WHO标准常规分析110例不育伴精索静脉曲张患者手术前后的精液质量。结果:110例精索静脉曲张患者术后精子密度、(A+B)级精子比率、有效精子数、精子活动率、活动精子数、精子低渗肿胀比率、正常形态精子比率较术前明显提高,两组差别有显著性意义(P0.05)。结论:精索静脉曲张手术能改善精液的质量。     

浅谈分子筛制氧系统的选择使用和管理

本文论述了分子筛制氧机的工作原理、主要组成部分及作用.强调了应严格遵守规章制度,认真做好制氧机的维护保养,加强质量监控和管理.同时阐述了医院在选购制氧系统时要综合分析影响其能耗的因素,在保证氧气产量和纯度的前提下,尽量降低系统能耗,提高长期运行的经济效益.     

Early and late components of error monitoring in violent offenders with psychopathy

BACKGROUND: One of the most recognizable features of psychopathy is the reduced ability to successfully learn and adapt overt behavior. This might be due to deficient processing of error information indicating the need to adapt controlled behavior. METHODS: Event-related potentials (ERPs) and behavioral components of error-monitoring processes were investigated in 16 individuals with psychopathy and in 18 healthy subjects. A letter version of the Eriksen flanker task was used in two conditions. The first condition (normal condition) required participants to press one of two buttons depending on the identity of the target stimulus. The second condition (signaling condition) required them to signal each time they had committed an error by making a second press on a signaling button. Early stages of error monitoring were investigated by using the error-related negativity (ERN/Ne) and post-error slowing as indexes. Later stages were explored by examining the error positivity (Pe) and signaling rates. RESULTS: Both groups showed similar ERN amplitudes and amounts of post-error slowing. The psychopathic group exhibited both reduced Pe amplitudes and diminished error-signaling rates compared with the control group. CONCLUSIONS: Individuals with psychopathy show intact early error processing and automatic behavioral adaptation but have deficits in later stages of error processing and controlled behavioral adaptation. This is an indication that individuals with psychopathy are unable to effectively use error information to change their behavior adequately.