• 【超声心动图比较主动脉瓣环运动和二尖瓣环运动。】 复制标题 收藏 收藏
    DOI:10.1111/j.1475-097X.2006.00684.x 复制DOI
    作者列表:Emilsson K,Egerlid R,Nygren BM
    BACKGROUND & AIMS: :Earlier studies have shown that the aortic root, in analogy with the mitral annulus, moves towards the left ventricular apex during systole. However, there are no earlier studies comparing the amplitude of the aortic annulus motion (AAM) with that of the mitral annulus (MAM), which was the main aim of the study. Another aim was to study the intra- and interobserver reproducibility (IIOR) of measuring AAM with M-mode and 2-D echocardiography as it is not obvious which of the methods that should be used. Twenty-one healthy subjects were examined by echocardiography. AAM and MAM were measured at different sites. IIOR was measured in 10 of the subjects. There was no significant difference between average AAM (15.3 +/- 1.5 mm) and average MAM (15.6 +/- 1.5 mm) and there was a rather good agreement between the variables. There was also no significant difference between AAM at the septal site (16.3 +/- 2 mm) and average MAM, but a significant difference between AAM at the lateral site (14.2 +/- 1.6 mm) and average MAM (P<0.001) and between the both sites of measuring AAM (P<0.001). The significant difference between the two sites of measuring AAM may have anatomical reasons but may also depend on difficulties in measuring AAM at the septal site where it has lower reproducibility than at the lateral site. IIOR of measuring AAM was good when using M-mode but poor when using 2-D echocardiography and AAM should preferably be measured using M-mode and not using 2-D echocardiography.
    背景与目标: : 早期的研究表明,与二尖瓣环类似,主动脉根部在收缩期向左心室心尖移动。但是,尚无较早的研究将主动脉瓣环运动 (AAM) 的幅度与二尖瓣环 (MAM) 的幅度进行比较,这是该研究的主要目的。另一个目的是研究使用M型和二维超声心动图测量AAM的观察者内和观察者间的可重复性 (ior),因为不清楚应使用哪种方法。通过超声心动图检查了21名健康受试者。在不同的地点测量了AAM和MAM。在10名受试者中测量了ior。平均AAM (15.3 +/-1.5毫米) 和平均MAM (15.6 +/-1.5毫米) 之间没有显着差异,并且变量之间有相当好的一致性。间隔部位的AAM (16.3 +/-2毫米) 与平均MAM之间也没有显着差异,但是,外侧部位的AAM (14.2 +/-1.6毫米) 和平均MAM (P<0.001) 之间以及测量AAM的两个部位之间的显着差异 (P<0.001)。测量AAM的两个部位之间的显着差异可能有解剖学原因,但也可能取决于在间隔部位测量AAM的难度,而间隔部位的重现性低于外侧部位。使用M模式时,测量AAM的ior很好,但使用二维超声心动图时较差,最好使用M模式而不是二维超声心动图测量AAM。
  • 【启动时大鼠发育阶段对肝肿瘤促进过程中生化标志物表达的影响。】 复制标题 收藏 收藏
    DOI:10.1159/000217665 复制DOI
    作者列表:Decloître F,Lafarge-Frayssinet C,Barroso M,Lechner MC,Ouldelhkim M,Frayssinet C
    BACKGROUND & AIMS: :The phenotypic response of rat liver to a carcinogenic protocol involving initiation/selection and promotion with and without phenobarbital (PB) feeding was studied in pubertal and adult male rats. Considering the early presence of preneoplastic nodular areas, it appeared that pubertal rats, initiated at 6-7 weeks, presented a higher susceptibility to the protocol than adult rats initiated at 9-10 weeks. Altered liver phenotype was characterized by: (1) gamma-glutamyl-transpeptidase (GGT) and glutathione S-transferase (GST) activities; (2) the expression of two forms of cytochrome P-450; de novo PB-inducible P-450 II B 1,2 and P-450 II C 7 normally expressed in 45-day-old rats and PB-inducible, and (3) the expression of albumin and alpha-fetoprotein cDNAs. In the absence of PB, the susceptibility of pubertal rat liver to hepatocarcinogenesis was related to a special metabolic phenotype enriched in GGT and GST activities by comparison with the quasi-normal expression of both P-450s. Adult rat liver presented a less altered pattern closer to that of noninitiated rat liver. During PB promotion, the loss of PB inducibility of P-450 II C 7 in pubertal rat liver suggested that the hormonal status of the animals could interact with initiation to modulate specific gene expression. The late phase of PB promotion revealed the loss of highly differentiated functions (P-450s, albumin), whereas enzymatic markers associated with preneoplastic foci showed a persistent high expression.
    背景与目标: : 在青春期和成年雄性大鼠中研究了大鼠肝脏对致癌方案的表型反应,该方案涉及在有或没有苯巴比妥 (PB) 喂养的情况下启动/选择和促进。考虑到肿瘤前结节区域的早期存在,看来在6-7周开始的青春期大鼠对该方案的敏感性高于在9-10周开始的成年大鼠。肝脏表型改变的特征是 :( 1) γ-谷氨酰转肽酶 (GGT) 和谷胱甘肽S-转移酶 (GST) 活性; (2) 两种形式的细胞色素P-450的表达; 从头PB诱导的P-450 II B 1,2和P-450 II C 7在45日龄大鼠和PB诱导的大鼠中正常表达,以及 (3) 白蛋白和甲胎蛋白cdna的表达。在没有PB的情况下,与两种P-450s的准正常表达相比,青春期大鼠肝脏对肝癌发生的敏感性与富含GGT和GST活性的特殊代谢表型有关。成年大鼠肝脏的变化较小,接近未启动的大鼠肝脏。在PB促进过程中,青春期大鼠肝脏中P-450 II C 7的PB诱导性丧失表明动物的激素状态可以与启动相互作用以调节特定基因表达。PB促进的晚期阶段揭示了高度分化的功能 (P-450s,白蛋白) 的丧失,而与肿瘤前灶相关的酶标记显示出持续的高表达。
  • 【庞贝病骨骼肌自噬和治疗酶的误用。】 复制标题 收藏 收藏
    DOI:10.1016/j.ymthe.2006.08.009 复制DOI
    作者列表:Fukuda T,Ahearn M,Roberts A,Mattaliano RJ,Zaal K,Ralston E,Plotz PH,Raben N
    BACKGROUND & AIMS: :Enzyme replacement therapy (ERT) became a reality for patients with Pompe disease, a fatal cardiomyopathy and skeletal muscle myopathy caused by a deficiency of glycogen-degrading lysosomal enzyme acid alpha-glucosidase (GAA). The therapy, which relies on receptor-mediated endocytosis of recombinant human GAA (rhGAA), appears to be effective in cardiac muscle, but less so in skeletal muscle. We have previously shown a profound disturbance of the lysosomal degradative pathway (autophagy) in therapy-resistant muscle of GAA knockout mice (KO). Our findings here demonstrate a progressive age-dependent autophagic buildup in addition to enlargement of glycogen-filled lysosomes in multiple muscle groups in the KO. Trafficking and processing of the therapeutic enzyme along the endocytic pathway appear to be affected by the autophagy. Confocal microscopy of live single muscle fibers exposed to fluorescently labeled rhGAA indicates that a significant portion of the endocytosed enzyme in the KO was trapped as a partially processed form in the autophagic areas instead of reaching its target--the lysosomes. A fluid-phase endocytic marker was similarly mistargeted and accumulated in vesicular structures within the autophagic areas. These findings may explain why ERT often falls short of reversing the disease process and point toward new avenues for the development of pharmacological intervention.
    背景与目标: : 酶替代疗法 (ERT) 已成为Pompe病患者的现实,Pompe病是一种致命的心肌病和骨骼肌肌病,该病是由糖原降解溶酶体酶酸 α-葡萄糖苷酶 (GAA) 缺乏引起的。该疗法依赖于重组人GAA (rhGAA) 的受体介导的内吞作用,似乎对心肌有效,但对骨骼肌无效。我们以前已经显示出GAA基因敲除小鼠 (KO) 的抗药性肌肉中溶酶体降解途径 (自噬) 的严重干扰。我们在这里的发现表明,除了在KO的多个肌肉群中增加糖原填充的溶酶体外,还存在逐渐的年龄依赖性自噬积累。治疗酶沿内吞途径的运输和加工似乎受到自噬的影响。暴露于荧光标记的rhGAA的活的单根肌肉纤维的共聚焦显微镜显示,KO中很大一部分内吞酶被捕获为自噬区域中的部分加工形式,而不是达到其目标-溶酶体。类似地,液相内吞标记物被错误地捕获并积累在自噬区域内的囊泡结构中。这些发现可以解释为什么ERT经常无法逆转疾病过程,并为药物干预的发展指明了新的途径。
  • 【凋亡的血管平滑肌细胞产生凝血酶。】 复制标题 收藏 收藏
    DOI: 复制DOI
    作者列表:Flynn PD,Byrne CD,Baglin TP,Weissberg PL,Bennett MR
    BACKGROUND & AIMS: Thrombin activation requires assembly of a prothrombinase complex of activated coagulation factors on an anionic phospholipid surface, classically provided by activated platelets. We have previously shown that anionic phosphatidylserine is exposed by rat vascular smooth muscle cells (VSMCs) undergoing apoptosis after serum withdrawal. In this study, using a chromogenic assay, we have shown thrombin generation by apoptotic VSMCs expressing c-myc (VSMC-myc) with an area under the thrombin-generation curve (AUC) of 305 +/- 17 nmol x min/L and a peak thrombin (PT) of 154 +/- 9 nmol/L. The thrombin-generating potential of the apoptotic VSMC-myc cells was greater than that of unactivated platelets (P = .003 for AUC; P = .0002 for PT) and similar to calcium-ionophore activated platelets (AUC of 332 +/- 15 nmol x min/L, P = .3; PT of 172 +/- 8 nmol/L, P = .2). Thrombin activation was also seen with apoptotic human VSMCs (AUC of 211 +/- 8 nmol x min/L; PT of 103 +/- 4 nmol/L) and was inhibited by annexin V (P < .0001 for AUC and PT). VSMC-myc cells maintained in serum generated less thrombin than after serum withdrawal (P = .0002 for AUC and PT). VSMCs derived from human coronary atherosclerotic plaques that apoptose even in serum also generated thrombin (AUC of 260 +/- 2 nmol x min/L; PT of 128 +/- 4 nmol/L). We conclude that apoptotic VSMCs possess a significant thrombin-generating capacity secondary to phosphatidylserine exposure. Apoptotic cells within atherosclerotic plaques may allow local thrombin activation, thereby contributing to disease progression.

    背景与目标: 凝血酶激活需要在阴离子磷脂表面上组装活化的凝血因子的凝血酶原复合物,通常由活化的血小板提供。我们以前已经表明,阴离子磷脂酰丝氨酸被大鼠血管平滑肌细胞 (VSMCs) 暴露,在血清戒断后发生凋亡。在这项研究中,使用显色测定法,我们已经显示表达c-myc (VSMC-myc) 的凋亡VSMC产生凝血酶,凝血酶产生曲线 (AUC) 下面积为305 +/- 17 nmol × min/L,凝血酶峰 (PT) 为154 +/- 9 nmol/L。凋亡的VSMC-myc细胞的凝血酶生成潜力大于未激活的血小板 (AUC P = .003; PT P = .0002),与钙离子载体激活的血小板相似 (AUC为332 +/- 15 nmol x min/L,P = .3; PT为172 +/- 8 nmol/L,P = .2)。在凋亡的人VSMCs中也可以看到凝血酶活化 (AUC为211 +/- 8 nmol × min/L; PT为103 +/- 4 nmol/L),并被膜联蛋白V抑制 (P < .0001 AUC和PT)。维持在血清中的VSMC-myc细胞产生的凝血酶少于血清戒断后 (对于AUC和PT,P = .0002)。来源于人冠状动脉粥样硬化斑块的VSMCs,即使在血清中凋亡也产生凝血酶 (AUC为260 +/- 2 nmol × min/L; PT为128 +/- 4 nmol/L)。我们得出的结论是,凋亡的VSMCs在磷脂酰丝氨酸暴露后具有显着的凝血酶生成能力。动脉粥样硬化斑块内的凋亡细胞可能会激活局部凝血酶,从而促进疾病进展。
  • 【大鼠角膜缘和中央角膜上皮中基因表达 (SAGE) 的系列分析。】 复制标题 收藏 收藏
    DOI:10.1167/iovs.06-0216 复制DOI
    作者列表:Adachi W,Ulanovsky H,Li Y,Norman B,Davis J,Piatigorsky J
    BACKGROUND & AIMS: PURPOSE:To identify genes preferentially expressed in the stem-cell-rich limbal epithelium of the rat cornea. METHODS:The limbal and central corneal epithelial cells of 6-week-old rats were isolated by microdissection. Serial analysis of gene expression (SAGE) libraries were constructed and analyzed, and in situ hybridization, reverse transcription-polymerase chain reaction (RT-PCR) and cDNA cloning were conducted by conventional procedures. RESULTS:The rat limbal and central corneal epithelial SAGE libraries consisted of 41,894 and 40,691 tags, respectively. After annotation, this was reduced to 759 transcripts specific for the limbal library and 844 transcripts specific for the central corneal library; 2292 transcripts overlapped. Transcripts encoding proteins with metabolic functions comprised the major functional category in both libraries. In situ hybridization and/or RT-PCR results of 12 of the most abundant, highly enriched transcripts in the limbal epithelium were in general agreement with the SAGE data and showed that these proteins are also expressed in the conjunctival epithelium. Interesting limbal-enriched transcripts encode WDNM1-like protein (similar to WDNM1/Expi, a putative secreted proteinase and inhibitor of metastasis), mesothelin (a cancer marker), marapsin (a trypsin-like serine protease that may control cell growth and migration), K4 and K15 (both cytokeratins), and membrane-spanning four-domain subfamily A member 8B. WDNM1-like protein was cloned and confirmed as a member of the four-disulfide core family. CONCLUSIONS:The SAGE results extend the database of genes expressed in the rodent cornea and suggest an association between several genes preferentially expressed in the limbal epithelium with cellular proliferation and migration.
    背景与目标:
  • 【衰老过程中大鼠脊髓神经元NeuN免疫反应性的丧失。】 复制标题 收藏 收藏
    DOI:10.1016/j.expneurol.2006.07.014 复制DOI
    作者列表:Portiansky EL,Barbeito CG,Gimeno EJ,Zuccolilli GO,Goya RG
    BACKGROUND & AIMS: :A morphologic study of the impact of aging on neuron marker expression was performed in different segments of the rat spinal cord. Spinal cord specimens from young (5 months), middle-aged (12 months) and senile (32 months) female rats were assessed. We found a complete loss of neuron-specific nuclear protein (NeuN) immunoreactivity in cervical, thoracic and lumbar segments of the senile animals whereas neuron-specific enolase (NSE) immunoreactivity was comparable in young and senile rats. These findings in otherwise morphologically well preserved spinal cord neurons are of interest and reveal that NeuN may not be a reliable marker to identify neurons in the spinal cord of aging rats.
    背景与目标: : 在大鼠脊髓的不同节段中进行了衰老对神经元标志物表达影响的形态学研究。评估年轻 (5个月),中年 (12个月) 和老年 (32个月) 雌性大鼠的脊髓标本。我们发现老年动物的颈,胸和腰段神经元特异性核蛋白 (NeuN) 免疫反应性完全丧失,而年轻和老年大鼠的神经元特异性烯醇化酶 (NSE) 免疫反应性相当。在其他形态学上保存良好的脊髓神经元中的这些发现令人感兴趣,并且表明NeuN可能不是鉴定衰老大鼠脊髓神经元的可靠标记。
  • 【通过血管平滑肌中收缩前糖原水平调节糖原利用,而不是葡萄糖利用。】 复制标题 收藏 收藏
    DOI:10.1021/bi970465a 复制DOI
    作者列表:Hardin CD,Roberts TM
    BACKGROUND & AIMS: These experiments were designed to determine whether glycogenolysis was influenced by the glycogen concentration of vascular smooth muscle. Segments of hog carotid artery smooth muscle were allowed to synthesize variable amounts of 1-[13C]glucosyl units of glycogen. Artery segments were then isometrically contracted in the presence of 2-[13C]glucose. Prior to and after isometric contraction, measurements were made of tissue glycogen content and superfusate glucose and lactate concentrations. 2-[13C]Lactate and 3-[13C]lactate peak intensities in the superfusate were measured using 13C-NMR spectroscopy. The tissue glycogen content decreased exponentially during the 4.5 h of isometric contraction (R2 = 0.990), despite more than a 3-fold range of glycogen concentration prior to contraction. The extent of glycogen utilization during a 3 h isometric contraction varied linearly with the precontraction glycogen concentration (R2 = 0.727). Lactate production specifically from glycogen breakdown increased with an increase in precontraction glycogen concentration (R2 = 0.620). During a 3 h isometric contraction neither the glucose utilization (R2 = 0.007) nor lactate production specifically produced from glucose (R2 = 0.00002) varied with the precontraction glycogen concentration. It is concluded that the rate of glycogenolysis is determined by the content of glycogen during prolonged contractions. In addition, precontraction glycogen levels influence the pathway for glycogen utilization but not the pathway for glucose utilization. Therefore, glycolysis and glycogenolysis behave independently in vascular smooth muscle.

    背景与目标: 这些实验旨在确定糖原分解是否受血管平滑肌糖原浓度的影响。允许猪颈动脉平滑肌段合成可变量的1-[13C] 糖原葡萄糖单元。然后在2-[13C] 葡萄糖存在下等距收缩动脉段。在等距收缩之前和之后,测量组织糖原含量和超融合物葡萄糖和乳酸浓度。使用13C-NMR光谱测量超融合物中的2-[13C] 乳酸和3-[13C] 乳酸峰强度。组织糖原含量在等距收缩的4.5小时内呈指数下降 (R2 = 0.990),尽管收缩前糖原浓度超过3倍。在3 h等距收缩期间糖原利用的程度随收缩前糖原浓度线性变化 (R2 = 0.727)。糖原分解产生的乳酸产量随着收缩前糖原浓度的增加而增加 (R2 = 0.620)。3小时的等距收缩葡萄糖利用率 (R2 = 0.007) 和特别由葡萄糖产生的乳酸产量 (R2 = 0.00002) 都不随收缩前糖原浓度而变化。结论是糖原分解速率由长期收缩期间糖原含量决定。此外,收缩前糖原水平会影响糖原利用的途径,但不会影响葡萄糖利用的途径。因此,糖酵解和糖原分解在血管平滑肌中独立运作。
  • 【腺苷A2受体在诱导大鼠海马CA1区长时程增强中的作用。】 复制标题 收藏 收藏
    DOI:10.1016/s0006-8993(97)00148-0 复制DOI
    作者列表:Kessey K,Trommer BL,Overstreet LS,Ji T,Mogul DJ
    BACKGROUND & AIMS: Although reductions in neurotransmission have been reported in response to agonist-mediated adenosine A1 receptor activation, the implications of A2 receptor activation on synaptic transmission have not been well explored. We examined the role adenosine A2 receptors play in the efficacy of neurotransmission between the Schaffer collateral-CA1 pathway in the rat transverse hippocampal slice. A2 receptor blockade in the presence of complete A1 receptor inhibition led to a reversible reduction of the field excitatory post-synaptic potential (EPSP) slope in response to low-frequency test pulses (0.033 Hz) indicating that A2 receptors can enhance synaptic transmission. A2 receptor blockade by the A2 antagonist, DMPX (3,7-dimethyl-1-propargylxanthine) prevented the induction of tetanus-induced long-term potentiation (LTP) of the EPSP. In contrast, no such effect on LTP induction was observed during A1 receptor blockade. We also examined the effects of DMPX on the induction of LTP during continued A1 receptor blockade with CPT. Under this condition, LTP was significantly reduced when compared to LTP induced in the presence of CPT alone. A similar result was found using the highly polar A2 antagonist 8-SPT (8-(p-sulfophenyl)theophylline) suggesting that the effects of DMPX on LTP were not due to a direct action on an intracellular intermediate. DMPX had no effect on LTP expression if applied 45 min following the tetanus indicating that A2 receptors play no significant role in the maintenance phase of LTP. Selective A2a receptor activation did not alter the field EPSP. Similarly, selective blockade of the A2a receptor did not interfere with tetanus-induced LTP. Increases in neuronal firing rates can result in elevations in the concentration of extracellular adenosine. Together, these results suggest that the A2 receptors may play an important role in the induction although not the maintenance of hippocampal LTP and that the effect is likely to be mediated by the A2b receptor.

    背景与目标: 尽管据报道,由于激动剂介导的腺苷A1受体激活,神经传递减少,但A2受体激活对突触传递的影响尚未得到很好的探讨。我们检查了腺苷A2受体在大鼠横海马切片中Schaffer collateral-CA1途径之间的神经传递功效中的作用。在完全A1受体抑制的存在下,A2受体阻断导致场兴奋性突触后电位 (EPSP) 斜率响应于低频测试脉冲 (0.033Hz) 的可逆降低,表明A2受体可以增强突触传递。A2拮抗剂DMPX (3,7-二甲基-1-炔基黄嘌呤) 对A2受体的阻断阻止了破伤风诱导的EPSP长期增强 (LTP) 的诱导。相反,在A1受体阻滞期间未观察到对LTP诱导的这种作用。我们还研究了在CPT持续阻断A1受体期间DMPX对LTP诱导的影响。在这种情况下,与单独在CPT存在下诱导的LTP相比,LTP显着降低。使用高度极性的A2拮抗剂8-SPT (8-(对磺苯基) 茶碱) 发现了类似的结果,表明DMPX对LTP的作用不是由于对细胞内中间体的直接作用。如果在破伤风后45分钟使用DMPX,则表明A2受体对LTP表达没有影响在LTP的维持阶段没有重要作用。选择性A2a受体激活不会改变EPSP。同样,选择性阻断A2a受体不会干扰破伤风诱导的LTP。神经元放电速率的增加会导致细胞外腺苷浓度的升高。这些结果表明,A2受体可能在诱导中起重要作用,尽管不是维持海马LTP,并且该作用可能是由A2b受体介导的。
  • 【interleukin-1对大鼠培养的Ito细胞的放松作用。】 复制标题 收藏 收藏
    DOI:10.1002/hep.510250618 复制DOI
    作者列表:Sakamoto M,Ueno T,Sugawara H,Torimura T,Tsuji R,Sujaku K,Sata M,Tanikawa K
    BACKGROUND & AIMS: Interleukin-1beta (IL-1beta) is closely involved in liver disorders. IL-1beta produces nitric oxide (NO) in vascular smooth muscle cells and relaxes vascular smooth muscle via cyclic guanosine 3',5'-monophosphate (cGMP). In this study, we evaluated the relaxing effect of IL-1beta on cultured Ito cells. Ito cells were isolated from the livers of male Wistar rats and cultured for 24 hours. Immunolocalization of inducible nitric oxide synthase (iNOS) and cGMP and intensity of fluorescence of cGMP were examined using a confocal laser microscope. Ito cells were treated with 0, 200, and 1,000 pmol/L IL-1beta, and the intracellular cGMP concentration was measured after 12 hours. Moreover, Ito cells treated with 200 and 1,000 pmol/L IL-1beta and not treated with IL-1beta were observed over 12 hours, and the area of the same Ito cell was compared before and after the addition of IL-1beta. Next, effects of N(G)-monomethyl-L-arginine (L-NMMA) and S-nitroso-N-acetyl-DL-penicillamine (SNAP) on Ito cell relaxation by IL-1beta treatment were examined. In Ito cells, immunofluorescence of iNOS was observed, and fluorescent intensity of cGMP increased after addition of IL-1beta. Intracellular cGMP concentration increased dose-dependently after addition of IL-1beta. Cell area significantly increased in the IL-1beta-treated group compared with the untreated group. Relaxation of Ito cells by IL-1beta treatment was inhibited by L-NMMA in a dose-dependent manner, but was enhanced by SNAP. These results indicate that IL-1beta produces NO in cultured Ito cells and relaxes the cells via cGMP.

    背景与目标: Interleukin-1beta (IL-1beta) 与肝脏疾病密切相关。IL-1beta在血管平滑肌细胞中产生一氧化氮 (NO),并通过环鸟苷3 ',5'-单磷酸 (cGMP) 松弛血管平滑肌。在这项研究中,我们评估了IL-1beta对培养的Ito细胞的松弛作用。从雄性Wistar大鼠的肝脏中分离Ito细胞,并培养24小时。使用共聚焦激光显微镜检查诱导型一氧化氮合酶 (iNOS) 和cGMP的免疫定位以及cGMP的荧光强度。Ito细胞用0、200和1,000 pmol/L IL-1beta处理,12小时后测定细胞内cGMP浓度。此外,在12小时内观察到用200和1,000 pmol/L IL-1beta处理和不用IL-1beta处理的Ito细胞,并比较在添加IL-1beta前后相同Ito细胞的面积。接下来,通过IL-1beta处理检查了N(G)-单甲基-L-精氨酸 (L-NMMA) 和S-亚硝基-N-乙酰基-DL-青霉胺 (SNAP) 对Ito细胞松弛的影响。在Ito细胞中,观察到iNOS的免疫荧光,加入IL-1beta后cGMP的荧光强度增加。加入IL-1beta后,细胞内cGMP浓度呈剂量依赖性增加。与未处理组相比,IL-1beta-treated组的细胞面积显着增加。IL-1beta处理对Ito细胞的松弛以剂量依赖性方式被l-nmma抑制,但被SNAP增强。这些结果表明,IL-1beta在培养的Ito细胞中产生NO,并通过cGMP使细胞松弛。
  • 【表型转换导致平滑肌肌膜的结构和功能改变。】 复制标题 收藏 收藏
    DOI:10.1016/j.yexcr.2006.07.012 复制DOI
    作者列表:Matschke K,Babiychuk EB,Monastyrskaya K,Draeger A
    BACKGROUND & AIMS: :Continuous changes in the length of smooth muscles require a highly organized sarcolemmal structure. Yet, smooth muscle cells also adapt rapidly to altered environmental cues. Their sarcolemmal plasticity must lead to profound changes which affect transmembrane signal transduction as well as contractility. We have established porcine vascular and human visceral smooth muscle cultures of epithelioid and spindle-shaped morphology and determined their plasma membrane properties. Epithelioid cells from both sources contain a higher ratio of cholesterol to glycerophospholipids, and express a less diverse range of lipid-associated annexins. These findings point to a reduction in efficiency of membrane segregation in epithelioid cells. Moreover, compared to spindle-shaped cells, cholesterol is more readily extracted from epithelioid cells with methyl-beta-cyclodextrin and its synthesis is more susceptible to inhibition with lovastatin. The inability of epithelioid cells to process vasoactive metabolites, such as angiotensin or nucleotides further indicates that contractile properties are impaired. Phenotypic plasticity extends beyond the loss of smooth muscle cell marker genes. The plasma membrane has undergone profound functional changes which are incompatible with cyclic foreshortening, but might be important in the development of vascular disease.
    背景与目标: : 平滑肌长度的持续变化需要高度组织化的肌膜结构。然而,平滑肌细胞也迅速适应改变的环境线索。它们的肌膜可塑性必须导致深刻的变化,从而影响跨膜信号转导以及收缩力。我们已经建立了上皮样和纺锤形形态的猪血管和人内脏平滑肌培养物,并确定了它们的质膜特性。来自两种来源的上皮样细胞均含有较高的胆固醇与甘油磷脂比例,并且表达与脂质相关的膜联蛋白的范围较少。这些发现表明上皮样细胞的膜分离效率降低。此外,与纺锤形细胞相比,胆固醇更容易从上皮样细胞中提取甲基-β-环糊精,其合成更容易受到洛伐他汀的抑制。上皮样细胞无法处理血管活性代谢产物,例如血管紧张素或核苷酸,进一步表明收缩特性受损。表型可塑性超出了平滑肌细胞标记基因的丧失。质膜发生了深刻的功能变化,与循环缩短不相容,但在血管疾病的发展中可能很重要。
  • 【通过过继转移CD4抗肿瘤T细胞杀死原位大鼠腺癌13762需要细胞表面MHC II类分子的肿瘤表达。】 复制标题 收藏 收藏
    DOI:10.1006/cimm.1997.1122 复制DOI
    作者列表:Frey AB,Cestari S
    BACKGROUND & AIMS: CD4+ anti-tumor T cells reactive with rat adenocarcinoma 13762 kill tumor in vitro and cause regression of tumor in vivo. The role of various host immune cells in CD4+ T-cell-mediated tumor elimination in vivo was investigated by adoptive transfer of anti-tumor T cell clones to recipients that were selectively depleted of individual immune cell types. By these means, macrophages and NK cells were found to be required for tumor killing. Depletion of host CD4+ T cells, CD8+ T cells, or neutrophils was without effect on tumor elimination by anti-tumor T cells. An essential role for antigen receptor-negative NK cells is likely dependent upon secretion of IFN-gamma from NK cells since treatment of tumor recipients with anti-IFN-gamma antibody prior to adoptive transfer and tumor challenge abrogated T cell killing, resulting in progressive tumor growth. Viability of adenocarcinoma 13762 or anti-tumor T cells was unaffected by treatment with either IFN-gamma or anti-IFN-gamma antibody in vitro, but cell surface MHC class II expression was induced in tumor cells by exposure to IFN-gamma. In addition, tumor cells were isolated from tumor-bearing animals by absorption using anti-MHC class II antibody, demonstrating that 13762 tumor expresses cell surface MHC class II antigens in situ. However, if hosts were depleted of NK cells before tumor challenge, MHC class II+ tumor was not recovered. Collectively these results suggest that adenocarcinoma 13762 is eliminated by MHC class II-restricted CD4+ T cells by direct tumor killing.

    背景与目标: 与大鼠腺癌反应的CD4 + 抗肿瘤T细胞13762在体外杀伤肿瘤并在体内引起肿瘤的消退。通过将抗肿瘤T细胞克隆过继转移到选择性耗尽个体免疫细胞类型的受体,研究了各种宿主免疫细胞在体内CD4 T细胞介导的肿瘤消除中的作用。通过这些方法,发现巨噬细胞和NK细胞是杀死肿瘤所必需的。宿主CD4 T细胞,CD8 T细胞或中性粒细胞的耗竭对抗肿瘤T细胞消除肿瘤没有影响。抗原受体阴性NK细胞的重要作用可能取决于NK细胞中IFN-γ 的分泌,因为在过继转移和肿瘤挑战之前用抗IFN-γ 抗体治疗肿瘤接受者消除了T细胞杀伤,导致进行性肿瘤生长。腺癌13762或抗肿瘤T细胞的活力在体外不受IFN-γ 或抗IFN-γ 抗体治疗的影响,但细胞表面mhcii类表达通过暴露于IFN-γ 在肿瘤细胞中诱导。此外,通过使用抗MHC II类抗体吸收从荷瘤动物中分离肿瘤细胞,证明13762肿瘤原位表达细胞表面MHC II类抗原。但是,如果宿主在肿瘤激发之前耗尽了NK细胞,则MHC II类肿瘤将无法恢复。这些结果共同表明,通过直接杀伤肿瘤,MHC II类限制性CD4 T细胞消除了腺癌13762。
  • 【大鼠原代星形胶质细胞培养物中单胺氧化酶的血清素代谢。】 复制标题 收藏 收藏
    DOI:10.1111/j.1471-4159.1990.tb05789.x 复制DOI
    作者列表:Fitzgerald LW,Kaplinsky L,Kimelberg HK
    BACKGROUND & AIMS: :The oxidative deamination of serotonin (5-HT) to 5-hydroxyindoleacetic acid (5-HIAA) by rat primary astrocyte cultures was investigated in intact cells using HPLC. All detectable 5-HIAA accumulated in the extracellular medium, and its rate of production was proportional to the 5-HT concentration over the tested range of 5 x 10(-7) to 10(-4) M. At 5 x 10(-7) M 5-HT, intracellular 5-HT was detectable only in astrocytes treated with monoamine oxidase (MAO) inhibitors. These findings are consistent with the idea that 5-HT taken up into astrocytes is not stored for re-release, but is rapidly metabolized to 5-HIAA, which is then extruded from the cell. At 5 x 10(-7) M 5-HT, 5-HIAA formation in intact cells was blocked 63% by the selective high-affinity 5-HT uptake inhibitor fluoxetine. 5-HT oxidation to 5-HIAA is carried out principally by MAO-A, because clorgyline was more effective at inhibiting the production of 5-HIAA than was pargyline. Radioenzymatic determinations of MAO activity in cell homogenates supported these findings, because under these conditions clorgyline was 1,000-fold more effective than pargyline at inhibiting MAO activity toward 14C-labelled 5-HT. However, the relatively selective MAO-B substrate beta-phenylethylamine (PEA) was also oxidized, showing that these cultures also contained MAO-B activity; the Km values for MAO-A oxidation of 5-HT and MAO-B oxidation of PEA were 135 and 45 microM, and Vmax values were 88 and 91 nmol/mg of total cell protein/h, respectively. Higher concentrations of PEA (greater than 20 microM) were oxidized by both MAO-A and MAO-B isozymes.(ABSTRACT TRUNCATED AT 250 WORDS)
    背景与目标: : 使用HPLC在完整细胞中研究了大鼠原代星形胶质细胞培养物将5-羟色胺 (5-HT) 氧化脱氨为5-羟基吲哚乙酸 (5-HIAA)。所有可检测到的5-HIAA都积累在细胞外培养基中,在5x10(-7) 至10(-4) M的测试范围内,其产生速率与5-HT浓度成正比。在5x10(-7) M 5-HT时,仅在用单胺氧化酶 (MAO) 抑制剂处理的星形胶质细胞中可检测到细胞内5-HT。这些发现与以下观点一致: 摄取到星形胶质细胞中的5-HT不会储存以重新释放,而是会迅速代谢为5-HIAA,然后从细胞中挤出。在5 × 10(-7) m5-ht时,选择性高亲和力5-HT摄取抑制剂氟西汀63% 阻断完整细胞中的5-HIAA形成。5-HT氧化为5-HIAA主要由MAO-A进行,因为clorgyline比pargyline更有效地抑制5-HIAA的产生。细胞匀浆中MAO活性的放射酶测定支持了这些发现,因为在这些条件下,clorgyline在抑制针对14c标记的5-HT的MAO活性方面比pargyline有效1,000倍。然而,相对选择性的MAO-B底物 β-苯乙胺 (PEA) 也被氧化,表明这些培养物也含有MAO-B活性; 5-HT的MAO-A氧化和PEA的MAO-B氧化的Km值分别为135和45微米,vmax值分别为88和91 nmol/mg的总细胞蛋白/h。较高浓度的豌豆 (大于20微米) 被MAO-A和MAO-B同工酶氧化。(摘要截短于250字)
  • 【创伤弧菌溶血素对大鼠腹膜腔肥大细胞的溶细胞作用。】 复制标题 收藏 收藏
    DOI:10.1099/00222615-32-1-39 复制DOI
    作者列表:Yamanaka H,Sugiyama K,Furuta H,Miyoshi S,Shinoda S
    BACKGROUND & AIMS: :The mode of action of Vibrio vulnificus haemolysin (VVH) on mast cells from the peritoneal cavity of the rat was examined. VVH induced histamine release, and damage to the mast cells, in a dose-dependent fashion. When 1 microgram of VVH was added to c. 10(5) mast cells at 37 degrees C, histamine release was observed after a lag period of 5-10 s, and was complete within 5 min. The action was temperature-dependent, and was not induced at 4 degrees C. Disodium cromoglycate, a membrane stabiliser for mast cells, inhibited the histamine release significantly, but the effect was not dose-dependent. Moreover, leakage of lactate dehydrogenase from VVH-treated mast cells was observed. These results suggest that VVH acts on the cell membrane of mast cells and is cytolytic.
    背景与目标: : 检查了创伤弧菌溶血素 (VVH) 对大鼠腹膜腔肥大细胞的作用方式。VVH以剂量依赖性方式诱导组胺释放并损害肥大细胞。当在37 ℃ 下将1微克VVH加入c. 10(5) 肥大细胞时,在5-10 s的滞后期后观察到组胺释放,并在5分钟内完成。该作用与温度有关,在4 ℃ 下未诱导。色甘氨酸二钠是肥大细胞的膜稳定剂,可显着抑制组胺的释放,但其作用不是剂量依赖性的。此外,观察到乳酸脱氢酶从VVH处理的肥大细胞中泄漏。这些结果表明,VVH作用于肥大细胞的细胞膜并具有溶细胞性。
  • 【神经元活动的同步促进单个大鼠新皮层神经元在早期发育中的存活。】 复制标题 收藏 收藏
    DOI:10.1111/j.1460-9568.1997.tb01449.x 复制DOI
    作者列表:Voigt T,Baier H,Dolabela de Lima A
    BACKGROUND & AIMS: Neural activity is thought to play a significant role during the development of the cerebral cortex. In this study, we examined the effects of global activity block or enhancement and the effects of patterned firing on the ability of cultured rat neocortical neurons to survive during the second week in vitro, beyond the beginning of synaptogenesis. Blockade of neuronal activity by adding tetrodotoxin (TTX) and increasing magnesium concentration in the medium strongly reduced the survival of cortical cells. Increasing neuronal activity by raising the external potassium concentration significantly improved the survival of cortical neurons. We postulated that in a developing neuronal network the survival of nerve cells is regulated by synaptically mediated events that involve changes in the intracellular calcium concentration. To examine this question further, we monitored the activity of the developing network by optically recording the intracellular calcium signals of many neurons simultaneously. These recordings show that in low magnesium neocortical neurons express synchronized oscillation of their intracellular calcium concentration. The ability of a network to synchronize the changes in intracellular calcium of multiple cells appeared gradually during the second week in culture, paralleled by both an increase in the synaptic density and a decline in the number of surviving neurons. By examining the fate of identified cells several days after a recording session, we found that those nerve cells that were co-activated with other neurons had a significantly higher chance to survive than cells that did not participate in synchronized events. These experiments demonstrate that during early cortical network development cortical neurons show synchronized firing activity and that the survival of neurons is at least partially dependent on this pattern of neuronal activity.

    背景与目标: 神经活动被认为在大脑皮层发育过程中起着重要作用。在这项研究中,我们研究了整体活动阻滞或增强的影响以及图案化放电对培养的大鼠新皮层神经元在体外第二周 (突触开始后) 存活的能力的影响。通过添加河豚毒素 (TTX) 和增加培养基中的镁浓度来阻断神经元活性,从而大大降低了皮质细胞的存活。通过提高外部钾浓度来增加神经元活性,显着改善了皮质神经元的存活。我们推测,在发育中的神经元网络中,神经细胞的存活受到突触介导的事件的调节,这些事件涉及细胞内钙浓度的变化。为了进一步研究这个问题,我们通过同时光学记录许多神经元的细胞内钙信号来监测发育网络的活动。这些记录表明,在低镁的新皮层神经元中,其细胞内钙浓度表达同步振荡。在培养的第二周,网络使多个细胞的细胞内钙的变化同步的能力逐渐出现,同时突触密度增加和存活神经元数量减少。通过在记录过程几天后检查已识别细胞的命运,我们发现与其他神经元共同激活的神经细胞比不参与同步事件的细胞存活的机会要高得多。这些实验表明,在早期皮质网络发育过程中,皮质神经元显示出同步的放电活动,并且神经元的存活至少部分取决于这种神经元活动模式。
  • 【大鼠中中核神经元对结肠直肠扩张的反应特征。】 复制标题 收藏 收藏
    DOI:10.1016/s0168-0102(97)01177-2 复制DOI
    作者列表:Kawakita K,Sumiya E,Murase K,Okada K
    BACKGROUND & AIMS: :The effects of colorectal distension (CRD) were examined on neurons located in and around the nucleus submedius (Sm) in the medial thalamus of urethane-anesthetized rats. A total of 66 units (49 in the Sm and 17 in immediately surrounding regions) responding to cutaneous pinch were tested to examine their responsiveness to the CRD. All the neurons that responded to cutaneous stimulation were nociceptive specific (NS) neurons. Based on their responses to the CRD the Sm neurons were classified into three types as follows: 23 (47%) of 49 neurons in the Sm and three (18%) of 17 neurons near the Sm had tonic excitatory responses with long-lasting after-discharges (type I); nine (18%) Sm neurons and four (24%) peri-Sm neurons were tonically excited but had no after-discharge (type II); and seven (14%) Sm neurons were inhibited (type III). Ten (20%) Sm neurons and 10 (59%) peri-Sm neurons did not respond to CRD. All the excitatory and inhibitory responses to CRD increased with increasing CRD pressure. Simultaneous application of CRD and cutaneous pinch did not produce a reduced response (nocigenic inhibition). These results demonstrate that most of the Sm neurons receive convergent viscerosomatic inputs from the colon and/or rectum and from the skin, suggesting that the Sm may participate in visceral nociception.
    背景与目标: : 检查了大肠扩张 (CRD) 对氨基甲酸乙酯麻醉大鼠内侧丘脑中中核 (Sm) 及其周围神经元的影响。测试了对皮肤挤压有反应的总共66个单位 (Sm中有49个,周围区域中有17个),以检查它们对CRD的反应能力。所有对皮肤刺激有反应的神经元都是伤害性特异性 (NS) 神经元。根据对CRD的反应,Sm神经元分为三种类型: Sm中49个神经元中的23个 (47% 个) 和Sm附近的17个神经元中的3个 (18% 个) 具有强直兴奋反应,放电后持续时间长 (I型); 九个 (18%) Sm神经元和四个 (24%) 周围Sm神经元被音调兴奋,但没有放电后 (II型); 七个 (14%) Sm神经元被抑制 (III型)。10个 (20%) Sm神经元和10个 (59%) 周围Sm神经元对CRD没有反应。随着CRD压力的增加,对CRD的所有兴奋和抑制反应均增加。同时应用CRD和皮肤捏合不会产生降低的反应 (抑制)。这些结果表明,大多数Sm神经元从结肠和/或直肠以及皮肤接收会聚的内脏体输入,表明Sm可能参与内脏伤害感受。

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