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83.
Synovial angiogenesis plays an important role in the inflammation in rheumatoid arthritis (RA). Vascular endothelial growth factor (VEGF) is a key molecule in angiogenesis and binds to specific receptors, known as vascular endothelial growth factor receptor I (VEGF RI). In this study, we investigated the therapeutic efficacy of anti-VEGF RI antibody (Ab) on RA using a collagen-induced arthritis (CIA) mouse model. Twelve DBA/1 mice were divided into three groups. All mice except controls were injected with type II collagen. Mice in the anti-VEGF-RI-Ab-treated groups were injected on one posterior paw with 50 μg anti-VEGF RI Ab twice weekly for 3 weeks. Arthritis score and paw thickness were measured and histopathologic assessment of joint sections was performed by hematoxylin–eosin. The infiltration of CD45+ inflammatory cells and neovascularization were evaluated by immunohistochemical staining. Anti-VEGF RI Ab significantly attenuated the arthritis severity and histopathologic findings in the CIA mice model. The infiltration of CD45+ cells decreased in anti-VEGF-RI-Ab-treated joint tissues. Staining for CD31 revealed reduced synovial neovascularization after anti-VEGF RI Ab treatment. The data showing that in vivo administration of anti-VEGF RI Ab suppressed arthritis in established CIA mice suggest anti-VEGF RI Ab treatment may serve as a new therapeutic modality for RA.  相似文献   
84.
孙国祥  杨婷婷 《中南药学》2010,8(2):143-148
目的建立色谱指纹图谱分离信息量指数理论,用分离信息量相关指数评价六味地黄丸(Liuweidihuang Pill,LWDHP)HPLC指纹图谱试验条件和结果,并结合系统指纹定量法鉴别其整体质量。方法采用RP-HPLC法,色谱柱为Century SIL C18BDS柱(250mm×4.6mm,5μm),以1%HAc溶液和1%HAc-甲醇溶液为流动相进行梯度洗脱,紫外检测波长265nm,柱温(30.00±0.15)℃,进样量10μL。用RIRIr、RJm)和RI啪)来评价试验条件和13批LWDHPs的HPI。C指纹图谱;以宏定性相似度S。和宏定量相似度Pm为参量对13批LWDHPs进行聚类分析,确定用其中10批生成对照指纹图谱(RFP),用系统指纹定量法鉴别13批LwDHPs的质量。结果以5-羟甲基糠醛为参照物峰,确定21个共有指纹峰,建立了LWDHP的HPLC指纹图谱。RJ、Rb、RJr(t)和RIz(q),评价结果表明9批LwDHPs指纹图谱的指纹分离度、信息量、信号以及均化性低于RFP,4批高于RFP。系统指纹定量法鉴别出7批质量合格,6批含量明显偏低。结论所建立的分离信息量指数能够指导实验条件的优化和一定程度地评价LWDHP的HPLC指纹图谱,结合系统指纹定量法可有效鉴别和控制LWDHP的质量。  相似文献   
85.
BACKGROUND: Immunoglobulin (Ig)E-sensitized persons with positive skin prick test, but no allergy symptoms, are classified as being asymptomatic skin sensitized (AS). The allergic type 1 disease is dependant on IgE binding to the high affinity IgE-receptor (FcepsilonRI) expressed on basophils and mast cells. However, a relationship between the AS status and FcepsilonRI has not been investigated. We aimed to characterize basophils from AS by looking at histamine release (HR) (sensitivity and reactivity) and the FcepsilonRI molecule, and compare it with nonatopic (NA) or allergic (A) persons. METHODS: Blood was obtained from NA (n = 14), grass and/or birch A persons (n = 17) and mono-sensitized grass or birch pollen AS (n = 12). The basophil sensitivity and reactivity were examined by anti-IgE triggered HR. Surface expression of FcepsilonRI and IgE were measured by flow cytometry, FcepsilonRIalpha protein was identified using a radioimmunoassay and Western blot. mRNA coding for the classic FcepsilonRIbeta-chain and the truncated form (FcepsilonRIbetaT) were determined by real-time PCR. RESULTS: The AS group was less reactive than NA or A persons when triggered by anti-IgE and had a significant higher number of nonresponders. However, there was no difference in sensitivity among the three groups and furthermore; the groups did not vary in FcepsilonRI- and IgE-surface expression, FcepsilonRIalpha-protein level or beta/betaT ratio. CONCLUSION: Basophils from AS persons are less reactive and include more nonresponders than basophils from NA and A persons, but do not differ regarding the FcepsilonRI molecule.  相似文献   
86.
Colchicine injected into the dentate gyrus of the hippocampus in adult rats preferentially destroys dentate granule cells. In the present study, we examine the light- and electron-microscopic correlates of the degeneration and evaluate whether the selectivity is preserved across the range of doses between 0.18 and 25 μg. Colchicine in a similar dose range was also injected into the cerebellum, olfactory bulb, striatum and cerebral cortex to examine local and regional differences in susceptibility to colchicine.The morphological changes accompanying degeneration in the dentate gyrus include fragmentation of the granule cell layer, appearance of small dark staining bodies in the cell layer, massive microglial invasion and profound disruption of granule cell axons and dendrites. Electron-microscopic observations suggest that the small dark bodies are probably condensed nuclei. The preferential vulnerability of dentate granule cells following intrahippocampal injection was observed at all doses. At doses between 0.18 and 2.5 μg there was little evidence of damage to neurons other than dentate granule cells. At the highest dose tested (25 μg) some pyramidal cells of regio superior near the injection site were destroyed, while granule cell destruction extended several mm from the injection site. Injection of 0.5–25 μg into the cerebellum resulted in the destruction of both granule cells and Purkinje cells, while cells which appeared to be neurons in the molecular layer were less affected. Following injection of 0.5 μg into the olfactory bulb, granule cells were extensively destroyed and there appeared to be some loss of mitral cells and an overall shrinkage of the injected bulb. Neuronal destruction in the striatum was observed with colchicine injections ranging from 2.5 to 25 μg, but at a given dose, the destruction was less extensive than for any other region tested except cerebral cortex.A possible application of this method and the implications of these results for other investigators using colchicine in the brain are discussed.  相似文献   
87.
Mast cells are important effector cells in allergic inflammatory reactions. The aggregation of the high-affinity IgE receptor (FcεRI) on the surface of mast cells initiates a complex cascade of signaling events that ultimately leads to the release of various mediators involved in allergic inflammation and anaphylactic reactions. The release of these mediators is tightly controlled by signaling pathways that are propagated through the cell by specific phosphorylation and dephosphorylation events. These events are controlled by protein kinases and protein phosphatases which either positively or negatively regulate the propagation of the signal through the cell. This review summarizes the role of both positive and negative regulators of FcεRI-induced mast cell activation.  相似文献   
88.
Functional, mature human mast cells have been generated by in vitro differentiation of CD133(+)/CD34(+) progenitor cells isolated from e.g. cord blood, peripheral blood, bone marrow or fetal liver. However, the protocols published so far require long term cultivation, i.e. up to 15 weeks for mast cell differentiation, which makes such approaches not only laborious but also costly. Here, we have developed a protocol for generating functional human mast cells from peripheral blood already within 7 weeks. Human CD133(+) progenitors were isolated from buffy coat preparations of peripheral blood and cultured in the presence of stem cell factor (SCF) and IL-6 for 7 weeks. IL-3 was added to the culture medium during the first 3 weeks, and fetal calf serum (FCS) added during the last week. In vitro differentiated CD133(+) cells exhibited multiple characteristics of mature mast cells. Thus, cells contained tryptase and expressed functional levels of FcepsilonRI. Anti-IgE stimulation induced significant release of histamine and PGD(2) and also of chemokines including MCP-1, IL-8, MIP-1alpha, and MIP-1beta. The fact that our in vitro differentiated mast cells are derived from a generally available source of progenitor cells makes this novel protocol widely applicable to any patient group, irrespective of age. Moreover, this progenitor source is more readily available than e.g. bone marrow or cord blood-derived progenitors. Consequently, our protocol has great potential in studies on mast cell biology and mast cell pathology, and e.g. on evaluation of drug effects.  相似文献   
89.
Leukocyte apheresis primarily used for treatment of inflammatory diseases such as inflammatory bowel disease (IBD). Beside an effect of the apheresis column, the plastic lines in the apheresis system might also have an effect due to interaction between the plastic surfaces and circulating leukocytes and plasma proteins. We recently reported generation of LL-37 in the plastic lines during leukocyte adsorbing apheresis. This generation might have a positive impact on the immunologic tolerance and therefore be one operational mechanism by which the apheresis treatment executes its effect. In the present study, we report a significant generation of sIL-1RI in the apheresis lines that is initially absorbed by the LCAP device. This finding, together with our previous data on IL-1Ra indicate that important members of the IL-1 family are significantly altered during the LCAP treatment of patients with IBD. Since IL-1 and its antagonists are important for regulation of inflammatory processes in IBD, we speculate that the LCAP related changes in sIL-1RI and IL-1Ra might impact the clinical outcome. These findings have to be taken into consideration when designing new apheresis techniques as well as sham-controlled studies.  相似文献   
90.
目的:探讨Weber评分、CD FI血流分级、RI、CA125四方面联合诊断早期卵巢癌的价值.方法:回顾性分析176例卵巢肿瘤的Weber评分、CD FI血流分级、RI、CA125四方面的差异.结果:本组超声诊断卵巢癌符合率87.5 %,CA125诊断符合率91.7 %,联合诊断符合率100.0 %;四者联合诊断的敏感性分别为100.0 %,特异性为98.1 %.结论:Weber评分、CD FI血流分级、RI、CA125四方面联合检查对卵巢恶性肿瘤的筛查及诊断有临床价值.  相似文献   
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