医患关系困境的制度影响因素及策略分析

目的 从制度角度探讨医患关系恶化的原因,并给出制度角度上具体的实施建议。方法 运用文献研究法及专题小组讨论法得出医患关系的制度影响因素集合,根据问卷调查结果进行因子分析研究。结果 医患关系深深嵌入到复杂的社会制度体系中,制度、道德文化、目标等八个领域决定医患关系和谐程度,基于因子分析结果,投入制度、强制约束制度和运行与管理制度是医患关系问题的深层制度根源。结论 通过立法建立可持续投入机制,建立解决医患冲突的法律法规、仲裁机制和责任分担制度,采取分级诊疗分化医疗费用压力,加强制度手段对医患关系的统筹管理。     

The association of human coagulation factors VIII,IXa and X with phospholipid vesicles involves both electrostatic and hydrophobic interactions

Blood coagulation factor X (FX) is converted to its active form (FXa) by a membrane bound multi-protein enzyme complex, comprised of factor VIII (FVIII), factor IXa (FIXa) and FX. Characterization of the molecular forces involved in the association of these proteins with phospholipids is crucial to understanding how these proteins bind to the lipid milieux of physiological membranes. In this report, the molecular forces involved in the association of FVIII, FIXa or FX with phospholipid vesicles (PLV) were characterized by ligand affinity chromatographic analyses. Treating FVIII-affinity columns with agents that disrupt electrostatic interactions caused elution of 15.2% of the total bound PLV, while agents that disrupt hydrophobic interactions caused elution of 84.8% of the total bound PLV. These results demonstrate that the association of PLV with FVIII is primarily hydrophobic. In contrast, the association of PLV with FIXa or FX is largely the result of electrostatic forces. This was established by observing that 71.3% and 78.9% of the total bound PLV was eluted from FIXa- and FX-affinity columns, respectively, by agents that disrupt electrostatic interactions. Of the total bound PLV, 28.7% and 21.2% were eluted from FIXa- and FX-affinity columns, respectively, by agents that disrupt hydrophobic interactions. These data demonstrate that hydrophobic forces play a heretofore unrecognized role in the association of PLV with FIXa or FX.     

The translation factors of Drosophila melanogaster

Synthesis of polypeptides from mRNA (translation) is a fundamental cellular process that is coordinated and catalyzed by a set of canonical ‘translation factors’. Surprisingly, the translation factors of Drosophila melanogaster have not yet been systematically identified, leading to inconsistencies in their nomenclature and shortcomings in functional (Gene Ontology, GO) annotations. Here, we describe the complete set of translation factors in D. melanogaster, applying nomenclature already in widespread use in other species, and revising their functional annotation. The collection comprises 43 initiation factors, 12 elongation factors, 3 release factors and 6 recycling factors, totaling 64 of which 55 are cytoplasmic and 9 are mitochondrial. We also provide an overview of notable findings and particular insights derived from Drosophila about these factors. This catalog, together with the incorporation of the improved nomenclature and GO annotation into FlyBase, will greatly facilitate access to information about the functional roles of these important proteins.     

Model analysis of difference between EGF pathway and FGF pathway

The difference in time course of Ras and mitogen activated protein kinase (MAPK) cascade by different growth factors is considered to be the cause of different cellular responses. We have developed the computer simulation of Ras-MAPK signal transduction pathway containing newly identified negative feedback system, Sprouty, and adaptor molecules. Unexpectedly, negative feedback system did not profoundly affect time course of MAPK activation. We propose the key role of fibroblast growth factor receptor substrate 2 (FRS2) in NGF/FGF pathway for sustained MAPK activation. More Grb2-SOS complexes were recruited to the plasma membrane by binding to membrane-bound FRS2 in FGF pathway than in EGF pathway and caused sustained activation of ERK. The EGF pathway with high concentration of EGF receptor also induced sustained MAPK activation, which is consistent with the results in the PC12 cell overexpressing the EGF receptors. The simulated time courses of FRS2 knock-out cells were consistent with those of the reported experimental results.     

凝血因子药物市场分析

凝血因子是一类特殊的药物,是血友病等血液疾病的治疗药物,目前已经成为血液制品的重要组成部分。国外已经有二十多种重组凝血因子药物上市,2015年全球重组凝血因子药物的市场规模已经达到78.54亿美元,未来还将持续增长,Baxalta公司的重组凝血因子产品销售额位居全球首位,达到28.40亿美元。国外有多种重组凝血因子处于研发阶段,其中长效重组凝血因子将成为新的市场增长点。国内各类凝血因子药物的批签发状况良好,且随着国家发展和改革委员会取消血液制品最高零售价,各类产品价格均有不同幅度增长,其中人纤原蛋白原增长幅度最高,达到189%。国产凝血因子市场空间巨大,但存在产品供给和研发力度不足等问题,发展受到限制,必须改革行业管理制度、提高血浆分离技术、加强重组产品研发。     

Defined medium for normal adult human prostatic stromal cells

Summary Stromal-epithelial interactions are pivotal in many aspects of prostatic biology. A defined culture system is critical for the investigation of factors that regulate the growth and differentiation of human prostatic stromal cells. We have identified conditions which promote stromal cell attachment and proliferation in serum-free medium. MCDB 201, originally developed for the clonal growth of chick embryo fibroblasts, proved to be a superior basal medium of those that we tested. Supplementation of MCDB 201 with basic fibroblast growth factor (FGF), insulin-like growth factor (IGF), and platelet-derived growth factor (PDGF) permitted attachment and exponential growth of cells throughout a 7-d period with an initial inoculum as low as 10³ cells per well of a 96-well microtiter dish. Using these assay conditions, we subsequently verified that basic FGF and IGF, but not PDGF, were required for optimal growth. No activity was found for heparin, transferrin, or the androgen R1881. Epidermal growth factor (EGF) didn’t stimulate growth when added to medium containing basic FGF and IGF, but was moderately stimulatory when added to basal medium alone. Cholera toxin inhibited growth. This simple and efficient culture medium provides a suitable assay system for more extensive studies of growth regulation and differentiation of human prostatic stromal cells, and will provide the basis for future development of a defined medium that supports clonal growth. Characterization of stromal-epithelial interactions will be facilitated by the use of this defined culture system for stromal cells in conjunction with the serum-free culture systems previously developed for human prostatic epithelial cells.     

Contribution of allosteric disulfide in the structural regulation of membrane-bound tissue factor–factor VIIa binary complex

Abstract

Two distinct populations, active and cryptic forms of tissue factor (TF), reside on the cell surface. Apart from phospholipid contribution, various models have been introduced to explain decryption/encryption of TF. The proposed model, the switching of Cys186–Cys209 bond of TF, has become the matter of controversy. However, it is well accepted that this disulfide has an immense influence upon ligand factor VIIa (FVIIa) for its binding. However, molecular level understanding for this remains unveiled due to lack of detailed structural information. In this regard, we have performed the molecular dynamic study of membrane-bound TF/TF–FVIIa in both the forms (±Cys186–Cys209 allosteric disulfide bond), individually. Dynamic study depicts that disulfide bond provides structural rigidity of TF in both free and ligand-bound forms. This disulfide bond also governs the conformation of FVIIa structure as well as the binding affinity of FVIIa toward TF. Significant differences in lipid–protein interaction profiles of both the forms of TF in the complex were observed. Two forms of TF, oxidized and reduced, have different structural conformation and behave differentially toward its ligand FVIIa. This disulfide bond not only alters the conformation of GLA domain of FVIIa in the vicinity but allosterically regulates the conformation of the distantly located FVIIa protease domain. We suggest that the redox status of the disulfide bond also governs the lipid-mediated interactions with both TF and FVIIa.

Communicated by Ramaswamy H. Sarma     

Fluorine and metals in Polygonum arenastrum Bor. from areas influenced by various types of industry

A herbaceous plant Polygonum arenastrum Bor. (=P. aequele Lindm., Polygonum aviculare ssp. aequale (Lindman) Ascherson & Graebner) (equal-leaved knotgrass), is a widespread, good coloniser, able to survive in wastelands where other species became extinct. Therefore, the bioindication abilities of this species for F, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, and Zn were investigated. P.arenastrum was collected from 90 sites affected by six polluting factories: copper smelter, chlor-alkali plant, former ferrous-chromium smelter and active combustion smelter, power plant, cement plant and coke plant. Plant samples were collected at 0.75, 1.5, 3 and 4.5 km from each of these polluters in N, S, W and E directions. For comparison, a control site with 16 sampling points was selected in an area relatively free from pollution. Concentrations of Cr, Cu, Fe, Pb and Zn in shoots and roots positively correlated with those in soil (both total and plant-available). Cu, Pb and Zn in P.arenastrum were within the values reported in literature as toxic for other plants with the highest bioaccumulation factor (BF) from soil to shoots for Cr and the highest translocation factor (TF) from roots to shoots for Co and Pb for more and less polluted and control sites. Polygonum arenastrum has a potential to accumulate Cr even in sites with low chromium concentration in soil. Polygonum arenastrum does not show any form of shoot injury at increased levels of F and metals in its tissues. Based on these characteristics we conclude that the ubiquitous P.arenastrum may be utilised as a relevant indicator of contamination in industrial zones and may function as an early warning system of increased toxicity in the environment.     

生长因子及其受体在淋巴瘤中异常表达的研究进展

生长因子是一类与受体结合后可以促进细胞增殖和调节细胞多项功能的多肽分子。生长因子及其受体信号通路包括Ras/MAPK、PI3K/AKT和STAT等不仅调控正常细胞的生物学行为,对恶性肿瘤细胞增殖、分化、转化和迁移也具有重要意义。研究发现多种生长因子如VEGF、PDGF和IGF及其受体在多种实体肿瘤如肺癌、乳腺癌、结肠癌中发现有异常表达,在淋巴瘤如DLBCL、PTCL、ML和NL中也存在异常的共同表达,提示在淋巴瘤中可能构成生长因子及其受体的自分泌/旁分泌环路。生长因子及其受体的表达对淋巴瘤患者的预后有一定指导意义,临床研究发现表达生长因子或其受体阳性患者比表达阴性患者有较差的临床预后。这可能与生长因子及其受体对淋巴瘤细胞的增殖、转移和耐药调控有关。目前生长因子及其受体已成为潜在的药物靶点,多种生长因子及其受体抑制剂在开发和临床试验中。本文就近年来生长因子及其受体在淋巴瘤中异常表达研究进展作简要综述。     

Acute Regulation of the Epidermal Growth Factor Receptor in Response to Nerve Growth Factor

PC12 cells possess specific receptors for both nerve growth factor and epidermal growth factor, and by an unknown mechanism, nerve growth factor is able to attenuate the propagation of a mitogenic response to epidermal growth factor. The differentiation response of PC12 cells to nerve growth factor, therefore, predominates over the proliferative response to epidermal growth factor. We have observed that the addition of nerve growth factor to PC12 cells rapidly produces a decrease in surface 125I-epidermal growth factor binding capacity. Unlike previously described nerve growth factor effects on 125I-epidermal growth factor binding capacity, which required several days of nerve growth factor exposure, the decreases we report occur within minutes of nerve growth factor addition: A 50% decrease in 125I-epidermal growth factor binding capacity is evident at 10 min. This rapid nerve growth factor response is concentration dependent; inhibition of 125I-epidermal growth factor binding is detectable at nerve growth factor levels as low as 0.2 ng/ml and is maximal at approximately 50 ng/ml, consistent with known ranges of biological activity. No demonstrable differences in the rate of epidermal growth factor receptor synthesis or degradation were observed in cells acutely exposed to nerve growth factor. Scatchard analysis revealed that acute nerve growth factor treatment decreased the number of both high- and low-affinity 125I-epidermal growth factor binding sites, while the receptor affinity remained unchanged. We have also investigated the involvement of various potential intracellular mediators of nerve growth factor action and of known intracellular modulatory systems of the epidermal growth factor receptor for their capacity to participate in this nerve growth factor activity.     

缺氧诱导因子1

缺氧诱导因子1是缺氧诱导细胞所产生的一种蛋白质,由一个120 ku的α亚基和一个91～94 ku的β亚基组成的异源二聚体.在缺氧条件下,促进红细胞生成素和糖酵解酶等基因的转录和表达,维持机体氧稳态.     

Biology and action of colony-stimulating factor-1

Colony-stimulating factor-1 (CSF-1), also known as macrophage colony-stimulating factor, controls the survival, proliferation, and differentiation of mono-nuclear phagocytes and regulates cells of the female reproductive tract. It appears to play an autocrine and/or paracrine role in cancers of the ovary, endometrium, breast, and myeloid and lymphoid tissues. Through alternative mRNA splicing and differential post-translational proteolytic processing, CSF-1 can either be secreted into the circulation as a glycoprotein or chondroitin sulfate-containing proteoglycan or be expressed as a membrane-spanning glycoprotein on the surface of CSF-1-producing cells. Studies with the op/op mouse, which possesses an inactivating mutation in the CSF-1 gene, have established the central role of CSF-1 in directly regulating osteoclastogenesis and macrophage production. CSF-1 appears to preferentially regulate the development of macrophages found in tissues undergoing active morphogenesis and/or tissue remodeling. These CSF-1 dependent macrophages may, via putative trophic and/or scavenger functions, regulate characteristics such as dermal thickness, male fertility, and neural processing. Apart from its expression on mononuclear phagocytes and their precursors, CSF-1 receptor (CSF-1R) expression on certain nonmononuclear phagocytic cells in the female reproductive tract and studies in the op/op mouse indicate that CSF-1 plays important roles in female reproduction. Restoration of circulating CSF-1 to op/op mice has preliminarily defined target cell populations that are regulated either humorally or locally by the synthesis of cell-surface CSF-1 or by sequestration of the CSF-1 proteoglycan. The CSF-1R is a tyrosine kinase encoded by the c-fms proto-oncogene product. Studies by several groups have used cells expressing either the murine or human CSF-1R in fibroblasts to pinpoint the requirement of kinase activity and the importance of various receptor tyrosine phosphorylation sites for signaling pathways stimulated by CSF-1. To investigate post-CSF-1R signaling in the macrophage, proteins that are rapidly phosphorylated on tyrosine in response to CSF-1 have been identified, together with proteins associated with them. Studies on several of these proteins, including protein tyrosine phosphatase 1C, the c-cbl proto-oncogene product, and protein tyrosine phosphatase-phi are discussed. Mol Reprod Dev 46:4–10, 1997. © 1997 Wiley-Liss, Inc.     

我国促肝细胞生长因子的研究和应用

促肝细胞生长因子具有促进细胞增殖和生长的作用,国内外研究较多。我国对肝细胞生 长因子的研究和应用主要集中在肝源性促肝细胞生长因子上。在总结国内学者历年研究成果的 基础上,结合我国生产和应用的实际情况,对促肝细胞生长因子的来源、结构、理化性质、生产及 应用情况进行了综述,有助于更深入研究。     

Activation of blood coagulation factor VIIa with cleaved tissue factor extracellular domain and crystallization of the active complex

Exposure of blood to tissue factor leads to the formation of a high affinity tissue factor/factor VIIa complex which initiates blood coagulation. As a first step toward obtaining structural information of this enzyme system, a complex of active-site inhibited factor VIIa (F.VIIai) and soluble tissue factor (sTF) was prepared for crystallization. Crystals were obtained, but only after long incubation times. Analysis by SDS-PAGE and mass spectrometry indicated the presence of sTF fragments similar to those formed by proteolytic digestion with subtilisin (Konigsberg, W., Nemerson, Y., Fang, C., Lin, T.-C. Thromb. Haemost. 69:1171, 1993). To test the hypothesis that limited proteolysis of sTF facilitated the crystallization of the complex, sTF fragments were generated by subtilisin digestion and purified. Analysis by tandem mass spectrometry showed the presence of nonoverlapping N- and C-terminal sTF fragments encompassing more than 90% of the tissue factor extracellular domain. Enzymatic assays and binding studies demonstrated that an equimolar mixture of N- and C-terminal fragments bound to factor VIIa and fully restored cofactor activity. A complex of F.VIIai and sTF fragments was prepared for crystallization. Crystals were obtained using microseeding techniques. The best crystals had maximum dimensions of 0.12 × 0.12 × 0.6 mm and showed diffraction to a resolution of 3 Å. © 1995 Wiley-Liss, Inc.     

La desesperanza como predictora de la soledad en adultos mayores

Background and objectiveHopelessness is characterized by a set of negative cognitive schemas about the future, conceptualized on the basis of three dimensions: affective, motivational and cognitive. This construct is linked to loneliness, the incidence of which in older adults is increasingly high. The aim of this research is to test whether hopelessness factors predict levels of loneliness in older adults.Material and methods138 non-institutionalized persons from Valencia city between 65-90 years old participated, with a mean age of 73.67 (SD = 4.8), and 59.4% were women. The Beck Hopelessness Scale (BHS) and University of California Los Angeles Loneliness Scale (UCLA) were administered to assess participants.ResultsThe motivational and cognitive factors acted as statistically significant predictors of loneliness, while the affective factor was not presented as a significant factor. The final model obtained an R² adj = .442, F(3, 87) = 23.97, p < .001.ConclusionsLoneliness is a phenomenon of great concern in the field of gerontology due to its high incidence and impact. The results indicate that hopelessness, specifically loss of motivation and negative expectations about the future, are critical issues for the development of feelings of loneliness in older adults. Thus, it is relevant to pay attention to these variables in order to apply loneliness prevention programs.     

pp42/44MAP Kinase Is a Component of the Neurogenic Pathway Utilized by Nerve Growth Factor in PC12 Cells

Nerve growth factor-stimulated mitogen-activated protein kinase (pp42/44MAP) kinase was characterized by sequential column chromatography on DEAE-Sephacel, phenyl-Sepharose CL4B, and S-200. The kinase displayed an apparent molecular mass of 42 kDa and reacted with an antiphosphotyrosine antibody. Peptide mapping of myelin basic protein revealed the presence of one phosphopeptide that was phosphorylated on Thr-97. pp42/44MAP kinase activity was dependent on Mg2+ and inhibited by K252a both in vitro and in vivo. Nerve growth factor-stimulated kinase activation was diminished by down-regulation of protein kinase C with 200 nM 12-phorbol 13-myristate acetate or with staurosporine (1 nM), a protein kinase C inhibitor. Genistein, a protein tyrosine kinase inhibitor, blocked nerve growth factor-mediated neurite extension as well as diminished activation of pp42/44MAP kinase. Our data demonstrate that activation of this kinase system by nerve growth factor displays a requirement for both protein kinase C as well as protein tyrosine kinase. In addition, other agents that are capable of promoting neurite outgrowth in PC12 cells, such as fibroblast growth factor or dibutyryl cyclic AMP, do so independently of activating this kinase system.     

基于人工神经网络的非线性拟合方法ⅡBP学习算法中各因素的影响

本文研究了人工神经网络BP学习算法中动量因子、隐节点数、学习速率、激活因子等对网络学习速度有影响的几个因素,并且找出了最佳值．