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51.
李桥川  邱录贵 《内科》2008,3(5):657-658
目的 研究不同来源CD34^+细胞归巢相关分子(HRM)的表达情况。方法采用免疫磁珠法(MACS)分选不同来源的CD34^+细胞,免疫荧光标记流式细胞仪测定HRM的表达。结果骨髓(BM)、动员后的外周血(mPB)及脐血(UCB)来源的CD34^+细胞均高表达细胞黏附分子CD49d、CD49e、CD54、CD11a、CD62L、CD44、CD31。UCB来源的CD34^+细胞表面表达的细胞黏附分子中,CD49e表达显著低于BM和mPB来源的CD34^+细胞(P〈0.05),CD54表达显著低于mPB来源者(P〈0.05),CXCR4表达显著低于BM来源者(P〈0.05)。结论UCB来源的造血干/祖细胞归巢能力低可能是UCB移植造血重建延迟的原因之一。  相似文献   
52.
Endoxin Antagonist Lessens Myocardial Ischemia Reperfusion Injury   总被引:5,自引:0,他引:5  
OBJECTIVE: To elucidate whether endoxin is one of important factors involved in myocardial ischemia reperfusion (MIR) injury, the change of myocardial endoxin level was determined in rats with MIR injury model and the effects of anti-digoxin antiserum (ADA), an endoxin specific antagonist, on MIR injury were studied. METHODS: MIR injury model was obtained by ligating left anterior descending coronary artery 30 min followed by 45 min reperfusion. Sprague-Dawley rats were randomly divided into six groups of 10 rats, each. Sham group, MIR group, normal saline group, ADA 9, 18 and 36 mg.kg(-1). ECG was continuously recorded. After reperfusion left ventricular myocardium samples of ischemic area were processed immediately. Myocardial endoxin level, Na(+)-K(+)-ATPase, Ca(2+)-ATPase, Mg(2+)-ATPase activities, and intramitochondrial Ca(2+) content were measured. RESULTS: Myocardial endoxin level was significantly increased; Na(+)-K(+)-ATPase, Ca(2+)-ATPase, and Mg(2+)-ATPase activities were remarkably decreased; intramitochondrial Ca(2+) content was remarkably raised; ST segments of ECG were significantly elevated and occurrence and scores of ventricular arrhythmias were significantly increased in early stage of reperfusion in rats with MIR. In all groups with ADA, myocardial endoxin level was remarkably decreased; Na(+)-K(+)-ATPase, Ca(2+)-ATPase and Mg(2+)-ATPase activities were drastically increased; intramitochondrial Ca(2+) content was declined; ST segments and ventricular arrhythmias were improved. CONCLUSION: Myocardial endoxin level was increased in MIR, which implies that the elevated endoxin may be one of major factors inducing MIR injury. This postulate is supported by the observation that ADA has protective and therapeutic effects against MIR injury probably by antagonizing the action of endoxin. The underlying mechanism may be ascribed to restoration of energy metabolism, and attenuation of intracellular Ca(2+) overload.  相似文献   
53.
目的:通过检测乙型肝炎患者外周血单核细胞各亚群分布情况以及HLA—DR表达水平,探讨慢性乙型肝炎患者外周血中CD14^+CD16^+单核细胞及HLA-DR的表达特点,以及与疾病进程之间的关系。方法:利用流式细胞仪(FCM)检测50例慢性乙型肝炎患者,其中21例免疫耐受(IT)患者、29例免疫活化(IA)患者,及31例正常人外周血CD14、CD16、HLA—DR的表达。同时调查肝功能、乙肝五项和血清HBVDNA等相应临床资料。结果:免疫活化组(IA)的CD14^+CD16^+亚群比率明显高于正常对照组和免疫耐受组(IT)(P〈0.01);单核细胞CD14^+CD16^+亚群HLA.DR表达明显高于CD14^+CD16^+亚群(P〈0.01);乙型肝炎患者CD14^+CD16^+单核细胞比率与ALT呈正相关(r=0.876,P〈0.01),与HBVDNA载量成负相关(r=-0.267,P〈0.01)。结论:CD14^+CD16^+单核细胞可能在乙型肝炎患者外周血中参与调节针对HBV的免疫反应,CD14^+CD16^+单核细胞与HBV复制和肝脏炎症之间存在相关性,因此检测单核细胞CD14^+CD16^+亚群及HLA-DR水平对于了解乙型肝炎患者疾病进程具有重要的临床应用价值。  相似文献   
54.
地方性砷中毒膜毒理学研究   总被引:5,自引:0,他引:5  
以红细胞膜作为观察标志,从膜毒理学角度探讨地方性砷中毒的发病机理。砷中毒病人血砷0.11±0.055μg/ml,红细胞膜砷0.101±0.05μg/mg膜蛋白,胞浆砷0.0012±0.0007μg/mgHb;电子显微镜观察到红细胞膜破损,异形红细胞,细胞表面毛刺样改变;胞膜的损伤,引起红细胞免疫功能下降,血液流变学的变化,细胞膜ATPase活性下降,红细胞电泳速度减慢和微循环变化,且甲皱微循环的变  相似文献   
55.
目的探讨CD8+CD28+T淋巴细胞胞外钙离子摄取与心脏移植急性排斥反应的相关性。方法用流式细胞仪分选对照组T0(正常SD大鼠组)、假手术组T1(sD大鼠除不进行心脏移植外,其他操过程都相同)、实验组T2(同种心脏移植组,WISTAR--}SD大鼠)术后第1、3、5、7、9、11天外周血CD8+CD28+T淋巴细胞,并用液闪仪测量CD8+CD28+T淋巴细胞胞外钙离子摄取量,分析CD8+CD28+T淋巴细胞胞外钙离子摄取量与心脏移植急性排斥反应程度的相关性。结果移植组CD8+CD28+T淋巴细胞胞外钙离子摄取率较假手术组、对照组明显升高,差异具有统计学意义(P〈0.05)。心脏移植后CD8+CD28+T淋巴细胞胞外钙离子摄取水平显著升高,与急性排斥反应严重程度成显著正相关,Spearman相关系数为0.488(P〈0.001)。结论通过测量外周血CD8+CD28+T淋巴细胞胞外钙离子摄取量,有助于早期监测心脏移植术后排斥反应,指导相应治疗。  相似文献   
56.
目的 探讨钠-钙交换体抑制剂KB-R7943对哇巴因诱发心衰家兔心律失常的影响.方法 40只成年家兔随机分为5组:假手术组、心衰对照组、哇巴因组、哇巴因合并KB-R7943(1μmol/L)组和哇巴因合并KB-R7943(5μmol/L)组.心衰组、哇巴因组、哇巴因合并KB-R7943(1 μmol/L)组和哇巴因合并K.B-R7943(5 μmol/L)组使用主动脉瓣关闭不全联合腹主动脉缩窄的方法建立心衰模型.建模8周后超声检测心功能,并利用Langendorff离体心脏灌流方法检测家兔各项离体心功能指标.灌流哇巴因(5μmol/L,4ml)诱发家兔心衰心脏产生心律失常,观察KB-R7943对离体心衰家兔心律失常的影响.结果 ①超声结果显示,与假手术组相比,心衰对照组家兔左室射血分数(LVEF)、短轴缩短率(%FS)均明显降低(P<0.05).②离体条件下,心衰对照组家兔离体心脏左室发展压(LVDP)、心率(HR)、室内压最大上升速率(+dp/dtmax)、室内压最大下降速率(-dp/dtmax)较假手术组均明显下降(P<0.05).③哇巴因组1h内总心律失常(TT)、室速(VT)、室颤(VF)持续时间较心衰对照组明显增加(P<0.05).④与哇巴因组比较,哇巴因联合应用KB-R7943组1h内TT、VT、VF持续时间明显减短(P<0.05);与1 μmol/L KB-R7943相比,5μmol/L KB-R7943可使哇巴因诱发TT和VT时间进一步缩短(P<0.05).结论 钠-钙交换体抑制剂KB-R7943可抑制哇巴因诱发心衰家兔心律失常的持续时间,且较高浓度(5 μmol/L)KB-R7943对哇巴因诱发心衰家兔心律失常的抑制作用更强.  相似文献   
57.
目的分析在艾滋病病毒(HIV)感染者/艾滋病(AIDS)病人(简称HIV/AIDS病人)中,应用血清隐球菌抗原筛查隐球菌感染的结果,为开展相关研究提供依据。方法对2012年10月至2013年7月,在贵阳市第五人民医院住院的348例HIV/AIDS病人进行血清隐球菌抗原检查,同时检查病人的CD+4T淋巴细胞(简称CD4细胞)计数;对血清隐球菌抗原阳性病人进行血培养、脑脊液(CSF)隐球菌抗原检查、墨汁染色及培养。结果 348例病人中,男256例,女92例,年龄19~77岁,平均(40.50±13.05)岁。血清隐球菌抗原阳性34例,阳性率9.77%(34/348),CD4细胞计数为0~1097个/mm3,中位数56个/mm3。CD4细胞计数≤50个/mm3组146例,50个/mm3组202例。CD4细胞计数≤50个/mm3和50个/mm3组病人阳性例数分别为24例和10例,阳性率为16.44%(24/146)和4.95%(10/202),两组间差异有统计学意义(u=3.56,P0.01)。血清隐球菌抗原阳性病人血培养阳性3例,CSF隐球菌抗原阳性27例,墨汁染色阳性22例,CSF培养阳性15例;34例病人中最后确认隐球菌感染33例。所有诊断隐球菌感染的病人血清隐球菌抗原均为阳性。结论 HIV/AIDS病人血清隐球菌抗原阳性率高,血清隐球菌抗原筛查有助于及时诊断隐球菌病,特别是CD4细胞计数≤50个/mm3的病人,推荐普遍检查。  相似文献   
58.
Among the bacteria that glide on substrate surfaces, Mycoplasma mobile is one of the fastest, exhibiting smooth movement with a speed of 2.0–4.5 μm⋅s−1 with a cycle of attachment to and detachment from sialylated oligosaccharides. To study the gliding mechanism at the molecular level, we applied an assay with a fluorescently labeled and membrane-permeabilized ghost model, and investigated the motility by high precision colocalization microscopy. Under conditions designed to reduce the number of motor interactions on a randomly oriented substrate, ghosts took unitary 70-nm steps in the direction of gliding. Although it remains possible that the stepping behavior is produced by multiple interactions, our data suggest that these steps are produced by a unitary gliding machine that need not move between sites arranged on a cytoskeletal lattice.The fastest of the Mycoplasma species is Mycoplasma mobile (M. mobile); they glide with a speed of 2.0–4.5 μm⋅s−1 (1, 2). Under an optimal-growth condition, cultivated single M. mobile cells are flask-shaped (Fig. 1A) and glide smoothly across a substrate covered with surface-immobilized sialylated oligosaccharides (3) in the direction of protrusion at a constant speed (Movie S1). Genomic sequencing and analysis have revealed that the mechanism must differ from other forms of motor protein systems and bacterial motility, because M. mobile lacks genes encoding conventional motor proteins in eukaryotes, such as myosin, kinesin, and dynein, in addition to lacking other motility structures in bacteria, such as flagella and pili (4). So far, three proteins have been identified as a part of the gliding machinery (Fig. 1B, Bottom): Gli123 (5), Gli521 (6), and Gli349 (7). The machinery units localize around the cell neck, and their number has been estimated to be ∼450 (2, 5, 8). Gli349 extends out from the cell membrane and shows a rod structure, ∼100 nm in total, with two flexible hinges when isolated (9). Notably, the machinery is driven by hydrolysis of ATP to ADP and inorganic phosphate, caused by an unknown ATPase (10). Because of the large size and characteristic structure of Gli349, and a series of studies with mutants and inhibitory antibodies (2, 11), it has been hypothesized that Gli349 works as a “leg” by binding to and releasing from a substrate covered with randomly arranged sialylated oligosaccharides (2) consuming the chemical energy of ATP. In addition, the pivoting movement of an elongated cell suggests that there are units working not simultaneously but rather independently to propel the cell forward (12). To test this hypothesis and identify conformational changes of a key part of the gliding machinery, we here designed an assay to detect the movement of M. mobile by high precision colocalization microscopy. In the presence of an excess number of binding targets in the solution, which decreased the number of active legs, stepwise displacement was shown for the first time, to our knowledge, to occur in gliding bacteria.Open in a separate windowFig. 1.Nanometer-scale tracking of Mycoplasma gliding. (A) A dark-field image of M. mobile. The image was captured with center-stop optics to maintain the high numerical aperture of the objective, which enabled a high spatial resolution (35). (Scale bar: 1 μm.) (B, Upper) Illustration of the fluorescent ghost. The gliding machinery was distributed around the neck portion, but only the active machinery bound to the glass is shown for simplicity. (Bottom) A construction model of the gliding machinery comprising three proteins: Gli123, Gli521, and Gli349. See the review by Miyata (2) for more detail. (C) A fluorescent image of the labeled ghost was acquired with a time resolution of 2 ms. (Scale bar: 1 μm; pixel size: 240 nm.) (D) The intensity profile of C. The XY area is 5 × 5 μm. (E) Gaussian fitting to D. Nanometer-scale tracking is achieved by positioning the peak of the 2D Gaussian function fitting to the intensity profile of the ghost. (F, Left) The speed of gliding ghosts at different [ATP]s in the solution (n = 129). The cyan curve shows a fit with Michaelis–Menten kinetics; Vmaxspeed and Km are 2.6 µm⋅s−1 and 61 µM, respectively. The dotted cyan curve shows a fit with the kinetics including the Hill coefficient; Vmaxspeed, [ATP50] and n are 2.2 µm⋅s−1, 43 µM, and 2.4, respectively. (Right) The speed of living cells with no ATP in the solution (2.1 ± 0.1 µm⋅s−1; n = 22). (G) Effect of SL on the gliding velocity of the ghost at saturated [ATP]s, 0.3–1.0 mM (n = 50).  相似文献   
59.
目的探讨脱氧胆酸(DOC)对肠道息肉恶变的影响及可能的分子机制。方法将24只4周龄Apcmin/+小鼠(该小鼠可自发形成肠道腺瘤)随机分为对照组(常规饮用水)及DOC组(含0.2%DOC饮用水),12周后处死,观察各组小鼠肠道息肉数目、大小及分布。HE染色评价息肉病理类型,免疫组织化学染色法检测细胞增殖标记物(proliferating cell nuclear antigen,PCNA)及Wnt通路关键分子β-catenin和cyclin D1的表达。结果 DOC组肠道息肉总数较对照组增加165%(57.00±3.07 vs 21.50±4.69,P0.001),其中小肠中段和远段的息肉数量分别增加了153%和371%。DOC组小肠息肉大、中、小直径(2 mm、1~2 mm和1mm)息肉数量与对照组对比分别增加89%(10.38±4.41 vs 5.50±2.93,P0.05)、295%(30.62±7.73 vs 7.75±4.59,P0.001)和112%(13.50±5.78 vs 6.38±2.45,P0.01)。HE染色示DOC组75%远段小肠和近段结肠发生黏膜内癌,余25%为中-高级别上皮内瘤变,而对照组仅为腺瘤未见癌变。免疫组织化学染色示DOC组PCNA阳性细胞数较对照组增加81%(90.83±2.60 vs50.10±4.51,P0.001),β-catenin由胞膜向胞质和胞核移位,cyclin D1胞核内表达增加(β-catenin:87.75±4.35 vs 56.30±4.29,P0.001;cyclin D1:71.93±4.01 vs 35.40±3.02,P0.001)。结论 DOC可能通过干预Wnt通路促进Apcmin/+小鼠肠道息肉细胞增殖,促使肠道腺瘤发展成为肠癌。  相似文献   
60.
摘要:目的阐述Panleucogating方法计数艾滋病病毒(HIV)感染者/AIDS病人(HIV/AIDS病人)CD4^+T淋巴细胞(CO4细胞)的方法、发展和应用。方法收集HIV/AIDs病人CD4^+细胞检测方法的文献,分析Panleucogating方法的可行性及其优势和不足。结果发现Panleucogating方法与常规方法检测的CD4^+细胞数值之间存在较高的相关性。该方法具有检测成本低、操作简单、检测迅速等优势。结论Panleucogating方法可用于HIV/AIDS病人CD4细胞计数的检测,在经济欠发达地区有应用价值。  相似文献   
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