哈白猪产后子宫内微生物区系的研究

实验通过用子宫内膜活检采样器采集子宫内容物样品、活菌计数、细菌的分离鉴定和药敏实验等方法 ,对 8头体重 12 0～ 15 0kg、年龄在 6～ 8岁的母猪产后子宫复旧期间子宫内的细菌进行研究 ,以探讨产后子宫内细菌的变化规律及对子宫复旧的影响。实验结果表明 ,在产后 0～ 1d ,子宫内细菌数量呈直线增加 ,在产后第 7d时 ,子宫内的细菌数量达到最多 ,此后其细菌数量逐渐下降 ;到产后第 2 5d时 ,子宫内的细菌数量已降为 (7.35± 2 .5 4 )× 10 2 个 /mg子宫样品。而细菌的种类在产后 1～ 7d较少 ,7～ 13d呈增长趋势 ,产后第 13d以后 ,细菌种类开始减少 ,直至接近于零。这说明产后子宫内环境经历了从污染到净化的过程 ,直至子宫复旧完毕。     

Ghrelin对豚鼠胃窦平滑肌细胞钙离子浓度的影响及与NO关系研究

目的:探讨Ghrelin对豚鼠胃窦平滑肌细胞内钙离子浓度的影响及其与一氧化氮(NO)的关系。方法:采用荧光免疫组化检测胃窦平滑肌细胞ghrelin受体(GHS-R)的表达;应用钙离子(Ca2+)指示剂Fluo-3/AM作为细胞内Ca2+的荧光探针,对负载培养的平滑肌细胞应用激光共聚焦显微镜技术,检测不同浓度ghrelin对平滑肌细胞内Ca2+荧光强度(FI)的影响,以及ghrelin受体阻断剂D-Lys3-GHRP-6、NO供体硝普钠(SNP),一氧化氮合酶(NOS)抑制剂N-硝基左旋精氨酸甲酯(L-NAME)对ghrelin调控Ca2+荧光强度的影响。结果:(1)豚鼠胃窦平滑肌细胞呈GHS-R免疫反应阳性表达.(2)随着ghrelin浓度升高(10-11,10-10,10-9,10-8,10-7mol/L),平滑肌细胞内Ca2+荧光强度逐渐升高,组间峰值(分别为54.7±11.5,58.1±5.7,64.8±6.6,84.9±7.1,95.7±10.5)和峰高(分别为1.8±0.3,2.1±0.8,5.3±1.3,28.9±4.2,37.6±3.7)均存在显著差异(P<0.05-0.01),即呈明显剂量依赖...     

Electron-microscopic microprobe analysis on the initial stages of mineral formation in the epiphyseal growth plate

Summary Dry thin sections (300–500 nm thick) of shock-frozen, freeze-dried and embedded epiphyseal growth plates from the proximal tibia of guinea pigs were cut longitudinally from the plate. Dark round bodies (ø<0.5 m) were observed using the scanning transmission mode of the electron microscope initially directly in the vicinity of the chondrocytes. They gradually spread out in the direction of the metaphysis to the center of the longitudinal septum and represent most probably the matrix vesicles. By use of a microscan of 0.25×0.25 m the element-concentrations of these bodies were measured. The measurements started on those bodies that could be clearly recognized and were extended to a length of 30–40 m in the metaphyseal direction. To obtain approximate quantitative results the registered Ca_K and P_K x-ray counts were directly compared with counts of fully mineralized regions, the Ca and P contents of which are known. Ca as well as P could be detected in the first visible vesicle-like structures (Ca0.2%, P0.4%) and increased steeply in the metaphyseal direction, amounting to approximately 6% Ca and 3% P. These results may lead to the conclusion that P_i becomes split from phosphate esters and transformed into the matrix vesicles already in a very early stage of enrichment. Incorporation of Ca may be coupled with this process.The authors express their thanks to the Deutsche Forschungsgemeinschaft for financial support     

低Ca~(2 )对豚鼠心室乳头肌电缆特性的影响

应用常规细胞内微电极技术和一支细胞外玻璃吸引电极,观察低Ca~(2 )对豚鼠心室乳头肌电缆特性及动作电位传导速度的影响。实验结果表明,1/6正常Ca~(2 )浓度(0.3mmol/L)溶液灌流时,与正常对照相比,空间常数减小23.9％(p<0.01),细胞内纵向电阻增大37.1％(p<0.01),动作电位传导速度减小16.1％(p<0.01)。单纯缺氧时,与正常对照相比,空间常数减小29.4％(p<0.01),膜时间常数减小30.1％(p<0.01),细胞内纵向电阻增大100％(p<0.01),动作电位传导速度减小28％(p<0.01)。低Ca~(2 )(0.6mmol/L)加缺氧时,上述变化更加明显,与正常对照相比,空间常数减小39.4％(p<0.01),膜时间常数减小25.8％(p<0.05),细胞内纵向电阻增大140.9％(p<0.01),动作电位传导速度减小37.7％(p<0.01)。     

ITPR1基因过表达对鸭子宫上皮细胞Ca2+浓度、脂质含量及钙转运相关基因的调控效应

肌醇1,4,5-三磷酸受体Ⅰ型 (Inositol 1,4,5-trisphosphate receptor 1,ITPR1) 是细胞内Ca2+释放的重要通道。为探讨ITPR1基因过表达对鸭子宫上皮细胞Ca2+浓度和脂质含量的调控效应及其对钙转运相关基因的影响,文中构建鸭ITPR1基因结构域的真核表达载体,转染鸭子宫上皮细胞,检测细胞ITPR1基因的过表达量、Ca2+浓度、细胞的脂质含量以及其他6个钙转运相关基因的表达量。结果显示,转染后子宫上皮细胞内的Ca2+浓度显著降低 (P<0.05),甘油三酯含量极显著升高 (P<0.01),高密度脂蛋白含量极显著降低 (P<0.01);相关性分析结果显示,C端ITPR1基因过表达量与总胆固醇含量呈极显著正相关 (P<0.01),与低密度脂蛋白含量呈显著正相关 (P<0.05),N端ITPR1基因过表达量与甘油三酯含量呈极显著正相关 (P<0.01),与Ca2+浓度呈显著负相关 (P<0.05);RT-qPCR结果显示,C端ITPR1基因过表达对IP3R2、VDAC2、CAV1基因的表达有显著抑制作用,N端ITPR1基因过表达对IP3R3、CACNA2D1基因的表达有显著促进作用。总之,ITPR1基因过表达能促进鸭子宫上皮细胞内Ca2+释放,促进甘油三酯、低密度脂蛋白和胆固醇的合成,抑制高密度脂蛋白的生成,且ITPR1基因过表达对6个钙转运相关基因的表达均产生影响。     

Effects of Na readmission on cellular45Ca fluxes in Na-Depleted guinea pig taenia coli

Summary The removal of Na from the medium causes a cellular Ca uptake in the smooth muscle of the guinea pig taenia coli which is rapidly reversed if medium Na is readmitted. This net extrusion was characterized in tissues which were first Na-depleted in a zero-Na (sucrose) solution. Li was able to substitute for Na in mediating this effect. K was also able to mimic Na in this respect if the depolarization-mediated Ca influx caused by the isotonic K solution was blocked with 10^–5 m D-600. The net Ca extrusion upon Na readmission was due to a small decrease in Ca influx, as well as a marked increase in the transmembrane Ca efflux rate, as revealed by⁴⁵Ca washout experiments. The increased⁴⁵Ca efflux upon Na readmission could be mimicked by Li, K, choline and tris. We conclude that the Na/Ca-exchange hypothesis is insufficient to explain these data, in that both Ca extrusion and⁴⁵Ca efflux can be stimulated in the absence of a Na gradient, or in the absence of any monovalent cationic gradient. These observations are discussed in terms of a possible intracellular competition of Ca and monovalent cations for anionic binding sites, as well as with regard to a possible direct stimulation of a plasmalemmal CaATPase by monovalent cations.     

Effect of sodium on cellular calcium transport in rat kidney

Summary The influence of extracellular Na (Na_o) on cellular Ca transport and distribution was studied in rat kidney slices. Calcium efflux from prelabeled slices was depressed when Na_o was completely replaced by choline or tetraethylammonium (TEA) ions and it was markedly stimulated when Na was reintroduced in a Na-free medium. However, reducing Na_o (with choline or TEA as substituting ions) did not increase the total slice⁴⁰Ca, their total exchangeable Ca pool, or the⁴⁰Ca or⁴⁵Ca of mitochondria isolated from these slices. Kinetic analyses of steady-state⁴⁵Ca desaturation curves showed that reducing Na_o depressed the exchange of Ca across the plasma membrane, slightly decreased the cytosolic Ca pool, but did not significantly affect the mitochondrial Ca pool and Ca cycling. Ouabain (10^–3m) which should reduce the Na gradient across the plasma membrane had no effect on calcium distribution and transport. These results suggest that in kidney cells low Na_o depresses Ca influx as well as Ca efflux; there may be an interaction between Na and Ca at a possible carrier located in the plasma membrane, but there is no Na/Ca exchange as described in several excitable tissues.     

Role of C5a-C5aR axis in the development of atherosclerosis

Complement component 5a (C5a) is a 74 amino acid glycoprotein and an important proinflammatory mediator that is cleaved enzymatically from its precursor, C5, on activation of the complement cascade. C5a is quickly metabolised by carboxypeptidases, forming the less-potent C5a desArg. C5a and C5a desArg interact with their receptors (C5aR and C5L2), which results in a number of effects which are essential to the immune response. C5a has a broad range of biological effects throughout the human body because the widespread expression of C5a receptors throughout the human organs enables C5a and C5a desArg to elicit a broad range of biological effects. Recently, accumulating evidence in humans and experimental animal models shows that the C5a-C5aR axis is involved in the development of atherosclerosis lesions. The absence or blockade of C5aRs greatly reduces the formation of atherosclerotic lesions or wire-injury-induced neointima formation in atherosclerosis-prone mice. Serum C5a level was related to the major adverse cardiovascular events in patients with advanced atherosclerosis and those with drug-eluting stent implantation. Thus, the C5a-C5aR axis may be a significant pathogenic driver of arteriosclerotic vascular disease, making C5a-C5aR inhibition an attractive therapeutic strategy.     

The local Ca concentration profile in the vicinity of a Ca channel

Intracellular Ca signaling is governed by diffusion and buffering of Ca ions. Mobile endogenous buffers increase the redistribution of Ca ions and tend to restrict the regions of elevated Ca concentrations to the close vicinity of the channel. These Ca microdomains dominate fast Ca signaling, as observed, e.g., in synaptic transmission. The steady-state solution of the linearized differential equations of buffered Ca diffusion, as developed by Neher and Naraghi and Neher (1–3), will be reviewed and generalized to the case of more than two buffers. Immobile buffers do not enter the steady-state equations, but instead slow down Ca diffusion and prolong the time to reach the steady state. Based on this phenomenon, a quite different putative mechanism to localize Ca will be suggested that is likely to be realized in photoreceptors where Ca source, Ca sink, and Ca sensor form a complex, as was recently reported (4–6).     

子宫动脉栓塞治疗子宫肌瘤伴月经过多的临床研究

目的：回顾分析24例子宫肌瘤伴月经过多患者入介治疗疗效和子宫动脉栓塞安全性。方法：选择24例子宫肌瘤伴月经过多患者进行子宫肌瘤供血动脉的栓塞。结果：插管栓塞动脉率100％,随访20年。治疗后1月,24例患者经月经明显减少,B超随访,3个月子宫肌瘤体积平均缩小30％,随访2年,其中2例行腹腔镜下子宫肌瘤经阴道摘除术,6例子宫肌瘤消失,16例子宫肌瘤体积平均缩小80％,结论：子宫肌瘤行介入治疗疗效肯定,对粘膜下子宫肌瘤及子宫肌瘤伴月经过多患者尤为适宜。     

中国两头乌猪品种内源性逆转录病毒基因研究

目的对5个中国两头乌猪品种(通城猪、东山猪、沙子岭猪、赣西两头乌猪和金华猪)及3个国外品种(大白猪、长白猪和杜洛克猪)猪内源性逆转录病毒(PERV)的核心蛋白(gag)基因、多聚酶(pol)基因、囊膜(env)基因的3个亚型A、B、C,分别从DNA和RNA水平上进行研究,以发现中国两头乌猪品种在异种器官移植中的资源优势。方法利用PCR方法在DNA水平上对PERV基因的三个亚型进行鉴定,并通过半定量PCR方法在RNA水平上检测通城猪和大白猪PERV各亚型在心、肝、脾、肺、肾、肌肉、脂肪、淋巴和脑组织中的表达谱。结果4个华中两头乌猪种中env-AB型为主要PERV亚型,分别占被测总数的92%～100%。在这4个品种中均没有检测到C亚型,金华猪以及3个国外猪种中均检测到了C亚型,病毒亚型种类也更丰富。半定量PCR实验结果显示gag、pol基因在两个品种9个组织中广泛表达,env-A在通城猪的心、肝、肺、脂肪和淋巴组织中表达量较低,env-B在通城猪的心脏和淋巴组织中表达量较低,而env-B在大白猪的肾脏中表达很低,其他所测8个组织中表达量都较高。结论通城猪、东山猪、赣西两头乌猪和沙子岭猪可以做为较佳的异种移植候选供体,具有良好的应用前景。