新生大鼠心肌细胞的分离和培养

为获得高纯度和高存活率的心肌细胞,探索心肌细胞大量培养的条件,并为进一步研究心肌细胞的细胞生物学特性奠定基础,同时为生理学和药理学研究提供细胞来源,试验采用胰蛋白酶顺序消化法及差速贴壁法,从1～2d龄新生大鼠的心肌组织中分离心肌细胞,观测心肌细胞的形态、结构、搏动状态和反映心肌细胞代谢状况的生化参数。结果表明,分离所得的心肌细胞纯度高,培养第3天就开始自发搏动,后连接成片,进而同步收缩;心肌细胞的亚显微结构包括肌丝、Z线、线粒体和大量糖原颗粒,葡萄糖比消耗率为7.44nmol/(个·d),乳酸比产率为3.83nmol/(个·d),乳酸转化率为51%,细胞代谢非常旺盛,说明试验培养条件有利于心肌细胞的气体交换和营养物质的摄取,从而有利于心肌细胞的生长。     

乳鼠心肌细胞的体外三维培养

【目的】探讨应用PLGA泡沫支架材料,在体外建造组织工程化心肌组织的可行性。【方法】采用顺序消化及差速贴壁法分离纯化乳鼠心肌细胞,将分离所得的心肌细胞接种于PLGA多孔支架材料上,观测复合体内心肌细胞的生长状况、超微结构、细胞代谢率及细胞组分的变化,并将其与正常心肌和二维培养的心肌细胞进行比较。【结果】复合体内的细胞具有心肌细胞的特殊超微结构,免疫组化显示其中的α-横纹肌肌动蛋白染色呈强阳性,与二维培养的细胞相比,细胞代谢更加旺盛。【结论】采用组织工程技术有可能在体外培育出组织工程化心肌组织。     

高糖培养对乳鼠海马神经元存活及c-fos蛋白表达影响

目的探讨高糖培养对乳鼠海马神经元存活及c-fos蛋白表达影响。方法无血清体外培养方法获得新生SD乳鼠海马神经元,分为正常组和高糖6、12、18、24h共5组。分别用PI/Hoechest33342染色法、免疫荧光细胞化学法检测检测海马神经元存活率及c-fos蛋白表达。结果高糖24h组海马神经元存活率明显低于正常组及高糖6、12、18h组(P<0.01)。高糖处理后,c-fos蛋白表达在6h开始出现,12h达高峰,此后逐渐下降(P<0.01)。结论高糖培养导致的乳鼠海马神经元存活率下降与c-fos蛋白表达有关。     

The relationship between charge movements associated with ICa and INa-Ca in cardiac myocytes

Ventricular myocytes exhibit a nifedipine-sensitive inward calcium current (ICa) and contracture when they are voltage clamped from -40 to 0 millivolt in the presence of caffeine and in the absence of extracellular sodium. However, upon repolarization they fail to relax because neither the sarcoplasmic reticulum nor the sodium-calcium exchange can reduce intracellular calcium. Sudden application of extracellular sodium during the contracture (but after repolarization) causes immediate relaxation and activates a transient inward sodium-calcium exchange current (INa-Ca), whose peak slightly precedes mechanical relaxation. The total charge carried by the nifedipine-sensitive ICa is twice the total charge carried by the transient inward INa-Ca. Assuming an exchange stoichiometry of three sodium to one calcium, these results indicate that all the calcium entering the cell during the initial depolarization is extruded by the sodium-calcium exchange.     

Glycolysis preferentially inhibits ATP-sensitive K+ channels in isolated guinea pig cardiac myocytes

In heart, glycolysis may be a preferential source of adenosine triphosphate (ATP) for membrane functions. In this study the patch-clamp technique was used to study potassium channels sensitive to intracellular ATP levels in permeabilized ventricular myocytes. Activation of these K+ channels has been implicated in marked cellular K+ loss leading to electrophysiological abnormalities and arrhythmias during myocardial ischemia. The results showed that glycolysis was more effective than oxidative phosphorylation in preventing ATP-sensitive K+ channels from opening. Experiments in excised inside-out patches suggested that key glycolytic enzymes located in the membrane or adjacent cytoskeleton near the channels may account for their preference for glycolytic ATP.     

Nuclear localization of histamine in neonatal rat brain

The concentration of histamine in the brains of neonatal rats is considerably higher than that in adults. Subcellular fractionation studies revealed that about 90 percent of the histamine content of neonatal rat brain is confined to the crude nuclear fraction obtained by differential fractionation. Purified nuclei prepared from these fractions retained 90 percent of their histamine content. The nuclear localization of histamine in the brains of neonatal rats suggests a function for histamine in modulating the growth processes of the neonatal brain.     

Regulation of calcium release is gated by calcium current, not gating charge, in cardiac myocytes

In skeletal muscle, intramembrane charge movement initiates the processes that lead to the release of calcium from the sarcoplasmic reticulum. In cardiac muscle, in contrast, the similarity of the voltage dependence of developed tension and intracellular calcium transients to that of calcium current suggests that the calcium current may gate the release of calcium. Nevertheless, a mechanism similar to that of skeletal muscle continues to be postulated for cardiac muscle. By using rapid exchange (20 to 50 milliseconds) of the extracellular solutions in rat ventricular myocytes in which the intracellular calcium transients or cell shortening were measured, it has now been shown that the influx of calcium through the calcium channel is a mandatory link in the processes that couple membrane depolarization to the release of calcium. Thus, intramembrane charge movement does not contribute to the release of calcium in heart muscle.     

秦香止泻方对HRV腹泻乳鼠小肠黏膜一氧化氮浓度的影响

目的研究秦香止泻方对人轮状病毒()腹泻乳鼠小肠黏膜一氧化氮(NO)浓度的影响,探讨该方干预HRV腹泻的作用机制。方法将192只出生3～5 d的乳鼠随机分为空白组,模型组,病毒唑组,秦香止泻方低、中、高剂量组,每组32只,空白组经口灌入不含HRV的培养液,其余各组经口灌入50μL(3.0×108PFU/mL)的Wa株HRV培养液。接种病毒12 h后,各给药组每只乳鼠经口给予相应的秦香止泻方药液50μL,病毒唑组给予同体积的病毒唑,空白组和模型组分别给予同体积的蒸馏水。连续给药8 d后用金胶体试纸方法检测粪便HRV抗原,观察一般情况和腹泻评分,采用微板法测定小肠黏膜NO浓度,并对腹泻评分与NO浓度进行相关性分析。结果接种病毒后第2天开始出现不同程度的腹泻,与模型组和病毒唑组比秦香止泻方能明显缩短腹泻病程,减轻腹泻程度,呈现一定的量效关系,差异有统计学意义(P<0.05);模型组与空白组比较,NO浓度明显升高,差异具有统计学意义(P<0.01),秦香中、高剂量组与模型组比较,第1～6天,NO浓度均显著降低(P<0.01),秦香高、中剂量组与病毒唑组比,第1～5天NO浓...     

鼻导管法高频喷射通气在新生儿呼吸衰竭中的应用

目的 :探讨鼻导管法高频喷射通气 (high- frequency jet ventilation,HFJV)在新生儿呼吸衰竭中的应用价值。方法 :对符合呼吸衰竭诊断标准的 36例新生儿 ,在积极治疗原发病同时采用鼻导管法 HFJV治疗。结果 :36例经通气治疗后 ,30例于 0 .5～ 1 h内缺氧症状及呼吸明显改善。 Pa O2 通气前后比较差异有显著性 (P<0 .0 1 ) ;通气前后 Pa CO2 在 型呼吸衰竭中差异有显著性 (P<0 .0 1 ) ,而在 型呼吸衰竭中差异无显著性 (P>0 .0 5)。 36例中治愈 31例 ,自动出院2例 ,4例因治疗无效而改用气管插管 ;除 5例有轻度腹胀、胃潴留外未见其他副作用。结论 :鼻导管法 HFJV是抢救新生儿呼吸衰竭的重要措施 ,尤适用于新生儿呼吸衰竭早期。     

Vitamin A: concentration in the rat liver Golgi apparatus

Vitamin A compounds (principally as retinyl esters) are concentrated in Golgi apparatus fractions from rat liver. The amounts vary with the vitamin A status of the liver and show an inverse relation to the concentration of ubiubinone. The results suggest a specific role of the Golgi apparatus in the mobilization or action, or both, of vitamin A compounds.     

机械牵张对大鼠心室肌连接蛋白43及神经钙粘附素表达的影响

目的通过观察机械牵张后大鼠左心室肌连接蛋白43(Cx43)及神经钙粘附素(N-cadherine)的改变来研究机械牵张对大鼠心室肌Cx43及N-cadherine表达的影响。方法采用膨胀球囊持续牵张Langendorff方法灌流的离体大鼠左心室心脏模型,从左心室游离壁心肌提取总核糖核酸(RNA),用逆转录-聚合酶链氏反应(RT-PCR)方法检测心室肌Cx43及N-cadherine的信使RNA(mRNA)。结果经过50 min持续牵张的大鼠左心室游离壁心肌Cx43 mRNA水平(2.105±0.480)及N-cadherine mRNA水平(1.650±0.233)较对照组(0.905±0.132,0.891±0.082)明显增高(P<0.01)。结论机械牵张使心肌细胞间连接相关蛋白表达增加,从而提高电流在相邻心肌细胞间的传导速度,可能导致心律失常的形成。     

酵母细胞膜系统对高温和高酒精浓度的适应性

在酒精生产中,应用嗜热微生物有很多优势.温度和酒精是酵母发酵的两个重要因素,当两个因素中的其中一个因素发生变化时,细胞中的脂肪酸、磷脂和麦角固醇也随之发生变化;当两个因素相互作用时,随着温度和酒精浓度的上升,酵母的耐受力下降.人们做了大量的研究,发现温度的上升和酒精浓度的增大会使细胞中热击蛋白和海藻糖发生变化.     

龙眼体细胞胚胎高质量浓度蔗糖成熟培养后的超微结构变化

以龙眼红核子品种的松散型胚性愈伤组织诱导的体细胞胚胎为材料 ,研究了体细胞胚胎经 5 0 g· L- 1 蔗糖成熟培养后的超微结构变化 .结果表明 ,经过成熟培养之后 ,龙眼体细胞胚胎细胞在结构和代谢上都发生了根本性的变化 .该研究有助于了解龙眼体细胞成熟机理以及进一步优化龙眼体胚再生系统     

Acquisition by innervated cardiac myocytes of a pertussis toxin-specific regulatory protein linked to the alpha 1-receptor

During development, the chronotropic response of rat ventricular myocardium to alpha 1-adrenergic stimulation changes from positive to negative. The alpha 1-agonist phenylephrine increases the rate of contraction of neonatal rat myocytes cultured alone but decreases the rate of contraction when the myocytes are cultured with functional sympathetic neurons. The developmental induction of the inhibitory myocardial response to alpha 1-adrenergic stimulation in intact ventricle and in cultured myocytes was shown to coincide with the functional acquisition of a substrate for pertussis toxin. A 41-kilodalton protein from myocytes cultured with sympathetic neurons and from adult rat myocardium showed, respectively, 2.2- and 16-fold increases in pertussis toxin-associated ADP-ribosylation (ADP, adenosine diphosphate) as compared to controls. In nerve-muscle cultures, inhibition of the actions of this protein by pertussis toxin-specific ADP-ribosylation reversed the mature inhibitory alpha 1-adrenergic response to an immature stimulatory pattern. The results suggest that innervation is associated with the appearance of a functional pertussis toxin substrate by which the alpha 1-adrenergic response becomes linked to a decrease in automaticity.     

瓜萎建白半夏汤对大鼠缺血再灌注 心肌细胞凋亡及Bcl-2 , Bax蛋白表达影响

目的研究瓜萎燕白半夏汤对缺血再灌注损伤大鼠心肌细胞凋亡及Bcl-2 , Bax蛋白表达影响〔方法通过 结扎大鼠冠状动脉左前降支造成心肌缺血再灌注损伤模型,各组动物至实验时限心肌缺血30 min、再灌注90 min后, 取出心脏、采用TUNEL检测心肌细胞凋亡,免疫组化方法检测心肌Bcl-2 , Bax蛋白表达、结果与假手术组对照,模型 组细胞凋亡率及Bax表达水平均明显升高、Bcl-2表达水平降低,组间比较差异有统计学意义(P<0.01);瓜萎燕白半夏 能有效降低Bax表达、升高Bcl-2表达水平,抑制细胞凋亡的发生,与模型组比较,差异有统计学意义(P<0.01)、结论瓜 萎燕白半夏汤可能通过上调Bcl-2 ,卜调Bax蛋白表达而有效抑制心肌缺血再灌注损伤大鼠心肌细胞凋亡的发生     

Video-rate molecular imaging in vivo with stimulated Raman scattering

Optical imaging in vivo with molecular specificity is important in biomedicine because of its high spatial resolution and sensitivity compared with magnetic resonance imaging. Stimulated Raman scattering (SRS) microscopy allows highly sensitive optical imaging based on vibrational spectroscopy without adding toxic or perturbative labels. However, SRS imaging in living animals and humans has not been feasible because light cannot be collected through thick tissues, and motion-blur arises from slow imaging based on backscattered light. In this work, we enable in vivo SRS imaging by substantially enhancing the collection of the backscattered signal and increasing the imaging speed by three orders of magnitude to video rate. This approach allows label-free in vivo imaging of water, lipid, and protein in skin and mapping of penetration pathways of topically applied drugs in mice and humans.     

曝二氧化碳气体对近具刺链带藻在高氨氮废水中生长的影响

养猪废水中丰富的氨氮可为微藻生长提供充足的养分,但是高质量浓度的氨氮会抑制微藻生长。以近具刺链带藻为对象,考查微藻在不同质量浓度的氨氮废水中的生长情况,同时探讨曝二氧化碳气体对微藻在高氨氮废水中生长的影响。结果表明,当初始氨氮的质量浓度为350~900 mg·L^-1时,近具刺链带藻的生长受到明显抑制,培养7 d后,各处理微藻的生物量仅增加0.08~0.13 g·L^-1。对不同质量浓度的氨氮废水进行曝二氧化碳气体处理后,微藻的生长情况明显改善,各处理的生物量增加了0.32~0.47 g·L^-1。未曝气处理的废水pH值呈下降趋势,7 d后下降了约0.50;而曝气条件下废水的pH值呈先增加后下降趋势,第1天到第2天上升了约1.50,从第2天开始至第7天,下降了约0.40。试验条件下氨氮的去除率在3.76%~20.10%。研究结果证实,过高质量浓度的氨氮确实会抑制微藻的生长,但通过曝二氧化碳气体的形式可以改善微藻在高质量浓度氨氮废水中的生长情况。     

化学沉淀法处理高浓度氨氮废水的动力学研究

从化学沉淀法处理高浓度氨氮废水的反应动力学角度出发,研究了温度对反应速率的影响,然后又结合动力学条件对该反应pH的影响进行了探讨。结果表明,温度对化学沉淀法处理高浓度氨氮废水的影响并不显著,而pH值的影响却很明显,一般要求反应的pH值控制在8～10之间。     

高光照强度和高CO2浓度对大花蕙兰无菌苗生长的影响

为缩短大花蕙兰无菌苗的生长周期,提高种苗质量,以大花蕙兰无菌苗为材料,采用组培微环境自动控制系统,研究了高光照强度和高CO2浓度对其生长的影响.结果表明:大花蕙兰无菌苗在光照强度为105 μmol·m-2·s-1和1 000 μmol·mol-1 CO2环境条件下培养30 d后与普通培养条件下的无菌苗相比,其干重、根的鲜重、根系活力、可溶性糖含量和叶绿素a/b均有显著增加,分别增加32%、29%、63%、73%和6%;培养50 d后无菌苗净光合速率比普通培养条件下的无菌苗提高了近7倍.表明高光照强度和高CO2浓度可显著增强无菌苗光合自养能力,加快大花蕙兰无菌苗的生长,提高种苗质量.     

血液稀释复合光量子综合疗法治疗冠心病心绞痛合并高粘血症患者的疗效观察

目的 :观察血液稀释复合光量子综合疗法对冠心病心绞痛合并高粘滞血症患者的疗效及安全性。方法 :88例随机分为 2组 ,治疗组 :48例在常规临床治疗基础上采用少量多次高容性血液稀释、紫外光及低强度 He- Ne激光体外照射与充氧血液磁化等处理后自血回输 ;对照组 :40例用低分子右旋糖酐加复方丹参液静滴。治疗后观察两组的临床症状、心电图缺血性 ST- T段、血脂、血液流变学及心肌耗氧指数等变化及不良反应 ,并作比较。结果 :治疗组的临床症状 ,心电图缺血性 ST- T改变 ,血脂、血液流变学及心肌耗氧指数均较对照组差异有显著性 ( P<0 .0 5 ) ,而且不良反应少。结论 :血液稀释复合光量子综合疗法对冠心病心绞痛合并高粘滞血症的患者有较好的近期临床疗效 ,安全性好 ,简便易行。