Regulation of CR3 (CD11b/CD18)-dependent natural killer (NK) cell cytotoxicity by tumour target cell MHC class I molecules

Phagocyte and NK cell CR3 functions as both an adhesion molecule and an iC3b receptor mediating cytotoxic responses to microorganisms. Cytotoxic activation of iC3b receptor function requires ligation of both a CD11b I-domain site for iC3b and a lectin site located in the C-terminus of CD11b. Because tumours lack the CR3-binding polysaccharides of bacteria and fungi, iC3b-opsonized tumours do not stimulate CR3-dependent cytotoxicity. Previous studies showed that NK cells could be induced to kill iC3b-opsonized tumours with small soluble β-glucans that bound with high affinity to CR3, bypassing the absence of similar polysaccharides on tumour membranes. Because CR3 signalling requires several tyrosine phosphorylation events, it appeared possible that CR3-dependent killing of autologous tumour cells might be suppressed by NK cell inhibitory receptors for MHC class I (KIR and CD94/NKG2) whose action involves recruitment of SHP-1 and SHP-2 tyrosine phosphatases. In the current study, Epstein–Barr virus (EBV)-transformed B cells were used as targets following opsonization with iC3b. Soluble β-glucan primed CR3 for killing of iC3b-coated B cells, but autologous class I-bearing targets were 84% more resistant than class I-deficient Daudi cells. Blockade of target cell class I with a MoAb specific for a domain recognized by both KIR and CD94/NKG2 resulted in comparable killing of class I⁺ B cells. By contrast, another MoAb to class II had no effect on cytotoxicity. These data suggest that NK cell recognition of class I suppresses CR3/tyrosine kinase-dependent cytotoxicity in the same way as it suppresses cytotoxicity mediated by other tyrosine kinase-linked receptors such as FcγRIIIA (CD16).     

甘草泻心汤治疗溃疡性结肠炎机制及临床研究进展

溃疡性结肠炎（UC）是一种慢性、非特异性炎症性肠病,病因与环境、遗传、感染和肠道微生物等多种因素相关。甘草泻心汤出自《伤寒论》,由炙甘草、黄芩、黄连、干姜、人参、半夏、大枣组成,具有调和寒热,消痞止利的功效。现代研究发现,甘草泻心汤单独或联合西药治疗UC具有显著疗效,其作用机制包括调节炎症因子、保护肠道黏膜和改善肠道菌群。通过查阅相关文献,对近年来甘草泻心汤及其单体治疗UC的相关机制与临床研究进行梳理与总结,以期为中医及中西医结合治疗UC提供理论依据并拓展治疗思路。     

髓核内注射预TGF-β1防软骨终板退行性变的实验研究

目的 探讨髓核内注射转化生长因子-β1(transforming growth factor-β1,TGF-β1)对预防椎间失稳后软骨终板退行性变的作用.方法 选用6月龄日本大耳白兔36只,随机分为对照组和预防组,每组18只.所有实验动物均制作为腰5-6、腰6-7椎间失稳模型.对照组不予任何处理.预防组在完成椎间失稳手...     

髓核内注射预TGF-β1防软骨终板退行性变的实验研究

目的 探讨髓核内注射转化生长因子-β1(transforming growth factor-β1,TGF-β1)对预防椎间失稳后软骨终板退行性变的作用.方法 选用6月龄日本大耳白兔36只,随机分为对照组和预防组,每组18只.所有实验动物均制作为腰5-6、腰6-7椎间失稳模型.对照组不予任何处理.预防组在完成椎间失稳手术后立即于同一切口通过侧后方入路显露腰5~6、腰6-7椎间盘,并行髓核内注射TGF-β1.于术后3、6个月各取8只进行HE染色及Mankin评分.结果 术后3、6个月预防组较对照组软骨终板退行性变明显减缓(P＜0.05,P＜0.01).结论 髓核内注射TGF-β1对椎间失稳后软骨终板退行性变具有明显的预防作用.     

Germline mutation in BRAF codon 600 is compatible with human development: de novo p.V600G mutation identified in a patient with CFC syndrome

Champion KJ, Bunag C, Estep AL, Jones JR, Bolt CH, Rogers RC, Rauen KA, Everman DB. Germline mutation in BRAF codon 600 is compatible with human development: de novo p.V600G mutation identified in a patient with CFC syndrome. BRAF, the protein product of BRAF, is a serine/threonine protein kinase and one of the direct downstream effectors of Ras. Somatic mutations in BRAF occur in numerous human cancers, whereas germline BRAF mutations cause cardio‐facio‐cutaneous (CFC) syndrome. One recurrent somatic mutation, p.V600E, is frequently found in several tumor types, such as melanoma, papillary thyroid carcinoma, colon cancer, and ovarian cancer. However, a germline mutation affecting codon 600 has never been described. Here, we present a patient with CFC syndrome and a de novo germline mutation involving codon 600 of BRAF, thus providing the first evidence that a pathogenic germline mutation involving this critical codon is not only compatible with development but can also cause the CFC phenotype. In vitro functional analysis shows that this mutation, which replaces a valine with a glycine at codon 600 (p.V600G), leads to increased ERK and ELK phosphorylation compared to wild‐type BRAF but is less strongly activating than the cancer‐associated p.V600E mutation.     

Results of the influenza virus surveillance in wild birds in Western part of Mongolia

ObjectiveTo present results of virological study of wild birds inhabiting Western Mongolia.MethodsOver a period of 2003–2008, we isolated 13 influenza A viruses: H1N1, H3N6, H13N8 and H4N6 subtypes. We did not isolate any H5N1 subtype, that still cause epizooty in wild birds and poultry.ResultsWe revealed taxonomic and ecological heterogeneity of the birds involved in maintenance of circulation of influenza viruses in the given territory. Influenza viruses were isolated from birds of 6 orders; among them there are species preferring water and semi-aquatic biotopes, one species preferring dry plain region, and also one species which can inhabit both dry and water biotopes.ConclusionsRepresentatives of all main orders of Western Mongolia avifauna are involved in support of influenza A virus circulation, highly pathogenic H5N1 influenza viruses were registered in Mongolia thus it's necessary to continue permanent influenza virus surveillance in wild birds' populations.     

An International Comparison of Web-based Reporting About Health Care Quality: Content Analysis

Background

On more and more websites, consumers are provided with public reports about health care. This move toward provision of more comparative information has resulted in different information types being published that often contain contradictory information.

Objective

The objective was to assess the current state of the art in the presentation of online comparative health care information and to compare how the integration of different information types is dealt with on websites. The content analysis was performed in order to provide website managers and Internet researchers with a resource of knowledge about presentation formats being applied internationally.

Methods

A Web search was used to identify websites that contained comparative health care information. The websites were systematically examined to assess how three different types of information (provider characteristics and services, performance indicators, and health care user experience) were presented to consumers. Furthermore, a short survey was disseminated to the reviewed websites to assess how the presentation formats were selected.

Results

We reviewed 42 websites from the following countries: Australia, Canada, Denmark, Germany, Ireland, the Netherlands, Norway, the United Kingdom, the United States, and Sweden. We found the most common ways to integrate different information types were the two extreme options: no integration at all (on 36% of the websites) and high levels of integration in single tables on 41% of the websites). Nearly 70% of the websites offered drill down paths to more detailed information. Diverse presentation approaches were used to display comparative health care information on the Internet. Numbers were used on the majority of websites (88%) to display comparative information.

Conclusions

Currently, approaches to the presentation of comparative health care information do not seem to be systematically selected. It seems important, however, that website managers become aware of the complexities inherent in comparative information when they release information on the Web. Important complexities to pay attention to are the use of numbers, the display of contradictory information, and the extent of variation among attributes and attribute levels. As for the integration of different information types, it remains unclear which presentation approaches are preferable. Our study provides a good starting point for Internet research to further address the question of how different types of information can be more effectively presented to consumers.