Detection of in vitro and in vivo cleavage of high molecular weight kininogen in human plasma by immunoblotting with monoclonal antibodies

Purified human high-mol-wt kininogen (HMWK), the cofactor of the contact phase of blood coagulation, migrated as a single band (approximately 110,000 mol wt) in a continuous buffer sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), but appeared as two separated bands (approximately 120,000 and 105,000 mol wt) when analyzed in a discontinuous buffer SDS-PAGE system. After elution from SDS polyacrylamide gels, each of the two bands showed coagulant activity. Six murine monoclonal antibodies (Mabs) against HMWK were produced and purified. In immunoblotting studies, three Mabs bound to the isolated alkylated heavy chain and one to the alkylated light chain of HMWK, whereas the remaining two bound only to the single-chain or unreduced two-chain molecule. None of the Mabs inhibited the clotting activity of HMWK or its binding to kaolin. Two of the Mabs, one directed against the light chain and one against the heavy chain, were used as specific probes to study HMWK in plasma samples using an immunoblotting technique. The anti-light chain Mab identified two distinct bands (approximately 120,000 and approximately 105,000 mol wt) in normal human plasma, but not in plasma from patients with hereditary HMWK deficiency. The anti-heavy chain Mab detected two additional bands (approximately 60,000 and approximately 54,000 mol wt) corresponding to low-mol-wt kininogen (LMWK) in normal plasma. A sensitive and specific quantitative immunoblotting assay of HMWK antigen in plasma was developed. Moreover, the immunoblotting technique with the anti-light chain Mab was used to detect the cleavage of HMWK in plasma samples after in vitro or in vivo activation of the contact system. The anti- light chain Mab demonstrated in vivo activation and cleavage of HMWK during an angioedema attack in a patient with hereditary angioedema and C1-inhibitor deficiency.     

Identification and quantitation of protein S in human platelets

Gel filtered human platelets contaminated with less than 0.02% of plasma protein S contained 490 ng of protein S antigen per 3 X 10(8) platelets, equivalent to 2.5% of protein S in whole blood. Three patients with heterozygous plasma protein S deficiency, a congenital disorder associated with venous thrombotic disease, had platelet protein S antigen levels that were 40% of the mean platelet level in ten normal volunteers. In immunoblotting analysis, platelet protein S was indistinguishable from plasma protein S. Thrombin stimulation of platelets caused release of 63% of total protein S antigen and this release was abolished when platelets were preincubated with metabolic inhibitors. Thrombin effected limited proteolysis of platelet protein S and this reaction was inhibited by calcium ions. Immunofluorescent staining of platelets using protein S antibodies demonstrated that protein S colocalized with fibrinogen, an established alpha-granule protein. Thus, human platelets contain protein S in alpha granules that can be released by thrombin stimulation. The released protein S may bind to stimulated platelets and thereby promote and localize the anticoagulant activity of activated protein C on the platelet surface.     

Strukturiertes klinisches Risikomanagement in einer Akutklinik

Background

A hospital is a dangerous place for patients. Multiple studies have demonstrated that errors are a significant problem in hospitals. At the same time it has been shown that a structured healthcare risk management offers numerous tools for risk reduction or risk prevention. The relevance of data due to errors in hospitals is unambiguous, therefore it is necessary to focus on this issue.

Objective

This article describes the basic principles and the implementation of a structured healthcare risk management. The process and tools of healthcare risk management are presented and explained.

Methods

A review of the literature on healthcare risk management was conducted and the currently used and established tools of healthcare risk management are presented.

Results

In the process of healthcare risk management several effective tools for the reduction and prevention of errors are available. These tools must be established in a structured risk management process.

Conclusion

A structured healthcare risk management in a hospital is no longer a ??nice to have?? but an absolutely ??must?? for the professional care of emergency patients.     

骨髓间充质干细胞在医学领域中的研究与应用

目的:骨髓间充质干细胞主要存在于全身结缔组织和器官间质中,自我更新和增殖能力强,在适宜的微环境里具有多向分化潜能。文章就骨髓间充质干细胞的生物学特性及其在医学领域应用的最新进展做一综述。资料来源:应用计算机检索PUBMED2000-01/2006-12期间的相关文章,检索词为“mesenchymal stem cell”,并限定文章语言种类为English。同时计算机检索中国期刊全文数据库2000-01/2006-12期间的相关文章,检索词为“骨髓间充质干细胞”,并限定文章语言种类为中文。资料选择:对资料进行初审,并查看每篇文献后的引文。纳入标准:文章所述内容应与骨髓间充质干细胞的发展现状及其临床应用相关。排除标准:重复研究或较陈旧的文献。资料提炼:共收集到160篇相关文献,68文献符合纳入标准,排除的92篇文献为内容陈旧或重复。选取符合纳入标准的30篇文献进行分析,分别涉及骨髓间充质干细胞的分离培养和鉴定、在医学领域中的应用、当前存在的问题及展望。资料综合:骨髓间充质干细胞是一类具有分裂增殖和多向分化潜能的干细胞,在适宜的诱导条件下可定向分化为成骨细胞、成软骨细胞、脂肪细胞、腱细胞、肌肉细胞和神经细胞等,且已在退行性及缺损性疾病、心血管疾病、肝移植、肺纤维化等疾病治疗方面取得良好效果。目前骨髓间充质干细胞在体内的细胞生物学和分子生物学作用机制仍不清楚,如何限定体内外诱导条件使其向所需细胞或组织定向分化以及移植时机、是否具有致瘤性等问题尚需深入研究。结论:骨髓间充质干细胞具有易获得、易培养、低免疫原性、易于外源基因的转入和表达等特性,已成为具有细胞治疗和基因治疗临床疾病潜在实用价值的有效载体。     

Cure of Helicobacter pylori infection and healing of duodenal ulcer: comparison of pantoprazole-based one-week modified triple therapy versus two-week dual therapy

Objective: Eradication of Helicobacter pylori ( H. pylori ) is recommended as the first-line therapeutic concept for reliable long-term prevention of duodenal ulcer (DU) relapse. Current treatment regimens vary in efficacy, complexity, and compliance. To assess the efficacy of pantoprazole in H. pylori eradication in parallel groups of patients using two eradication regimens.
Methods: Patients, (18–85 yr old; intention-to-treat,  n = 286  ) with proven DU, positive rapid urease test (biopsy), and ¹³C-urea breath test (UBT) were included in a prospective, randomized, multicenter study. Modified triple therapy consisted of 40 mg pantoprazole b.i.d ., 500 mg clarithromycin t.i.d ., and 500 mg metronidazole t.i.d . for 7 days (PCM therapy); dual therapy consisted of 40 mg pantoprazole b.i.d . and 500 mg clarithromycin t.i.d . for 14 days (PC therapy). In both groups 40 mg pantoprazole o.d . was given until day 28 when healing of DU was evaluated endoscopically; H. pylori status was assessed by UBT on day 56.
Results: H. pylori eradication rate was 95% in PCM versus 60% in PC therapy groups (per-protocol population,   p < 0.001  ), and 82% in PCM versus 50% in PC therapy in the intention-to-treat patient population (   p < 0.001  ). The DU healing rate was 98% in the PCM and 95% in the PC therapy groups (per-protocol population). Both regimens were similarly well tolerated. Adverse events in both regimens included taste disturbance, diarrhea, and increased serum concentration of liver enzymes, at an incidence of < 10%.
Conclusions: Compared to 2-wk PC therapy (pantoprazole and clarithromycin), the 1-wk PCM therapy (pantoprazole, clarithromycin, and metronidazole) is a significantly superior and highly promising strategy for eradication of H. pylori .