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1.
罗骏  沈成兴 《高血压杂志》1999,7(3):230-232
了解低密度脂蛋白的致动脉粥样硬化( A S)的机制及维拉帕米的影响。 方法:使用放射配基法观察人单核巨噬细胞对氧化低密度脂蛋白的代谢及维拉帕米的影响。 结果:氧化低密度脂蛋白在人单核巨噬细胞中的结合、摄取和降解较低密度脂蛋白增加。维拉帕米增加人单核巨噬细胞对氧化低密度脂蛋白和低密度脂蛋白的结合和摄取,不伴降解的增加。 结论:低密度脂蛋白经氧化后在人单核巨噬细胞中代谢发生改变,促进 A S的形成,维拉帕米通过改变其代谢途径,具有抗 A S的作用。  相似文献   

2.
为探索巨噬细胞集落刺激因子、清道夫受体、氧化型低密度脂蛋白与动脉粥样硬化的关系,观察了重组人巨噬细胞集落刺激因子对小鼠腹腔巨噬细胞清道夫受体途径的影响以及重组人巨噬细胞集落刺激因子对氧化型低密度脂蛋白所致细胞内胆固醇酯积聚的影响.结果发现重组人巨噬细胞集落刺激因子能增加培养的小鼠腹腔巨噬细胞表面的清道夫受体数目,使之对氧化型低密度脂蛋白的结合和降解呈现剂量和时间依赖性增加,并使细胞内胆固醇酯积聚增多.表明巨噬细胞集落刺激因子可通过增加清道夫受体数目使小鼠腹腔巨噬细胞对氧化型低密度脂蛋白的结合和降解增多,从而增加细胞内胆固醇酯含量,促进动脉壁内泡沫细胞形成.  相似文献   

3.
糖基化LDL增加胞浆钙浓度及脂质沉积   总被引:2,自引:0,他引:2  
观察了糖基化低密度脂蛋白(glc-LDL)与人单核巨噬细胞相互作用时细胞内钙离子浓度及脂质代谢的改变。胞桨内游离钙离子浓度较正常LDL组升高(P<0.05),细胞结合、摄入和降解glc-LDL均较正常LDL升高,结合glc-LDL具饱和趋势,细胞总胆固醇含量增加(P<0.05)。提示人单核巨噬细胞代谢glc-LDL途径与正常LDL不同,细胞表面可能存在糖基化LDL受体,此过程伴脂质沉积和钙质积聚,使巨噬细胞易变为泡沫细胞,可能为糖尿病患者易患动脉粥样硬化的原因之一。  相似文献   

4.
动脉粥样硬化的形成是动脉壁内泡沫细胞逐渐沉积的慢性炎症过程。循环中的氧化脂质特别是氧化型低密度脂蛋白胆固醇,以及一些体液因子、细胞因子均可引起单核巨噬细胞表面的清道夫受体表达增加,单核巨噬细胞吞噬大量含胆固醇的脂质,胆固醇流出减少,形成泡沫细胞,并在内皮下聚集,从而促进动脉粥样硬化的发生。  相似文献   

5.
糖基化低密度脂蛋白对细胞脂代谢及钙离子浓度的影响   总被引:2,自引:0,他引:2  
观察糖基化低密度脂蛋白与人单核巨噬细胞相互作用对细胞脂代谢及钙离子浓度的影响。细胞降解glc-LDL较正常LDL组升高,结合glc-LDL具饱和趋势,亲和常数为17.82mg/L最大亲和结合为434.78mg/g细胞蛋白,细胞内部总胆固醇含量升高,细胞游离钙离子浓度升高。提示人单核巨噬细胞代谢glc-LDL途径与正常LDL不同,此过程伴脂增加和钙离子浓度升高,可能为糖尿病病人易患动脉粥样硬化的原因  相似文献   

6.
目的建立人外周血单核细胞源性泡沫细胞模型,为研究动脉粥样硬化机制及其防治提供新途径。方法采用一次性密度梯度超速离心法从血浆中分离低密度脂蛋白,以Cu^2+诱导法将其氧化修饰成氧化低密度脂蛋白。采用密度梯度离心法和塑料吸附法从冠心病患者外周血中分离出单核细胞.首先以50nmol/L佛波酯刺激48h使之转化为巨噬细胞,然后与80mg/L氧化低密度脂蛋白共孵育24h,使之转化为泡沫细胞。结果经50nmol/L的佛波酯诱导48h后,光镜下发现单核细胞已转化为典型的巨噬细胞。油红O染色发现,与80mg/L氧化低密度脂蛋白共孵育24h后培养细胞中出现了大量的红染颗粒。高效液相色谱法测定细胞内胆固醇提示细胞内总胆固醇明显增加,其中胆固醇酯含量大于游离胆固醇,符合泡沫细胞的定义。结论直接采用冠心病患者外周血单核细胞成功地建立了泡沫细胞疾病模型,其病理生理学特性接近于体内状况,可为研究动脉粥样硬化机制和药物防治提供一种可靠的病理细胞模型。  相似文献   

7.
目的观察C反应蛋白和高密度脂蛋白对单核细胞株THP-1来源的巨噬细胞血凝素样氧化型低密度脂蛋白受体1蛋白和mRNA表达的影响,以及血凝素样氧化型低密度脂蛋白受体1表达的变化与细胞内胆固醇含量变化的关系。方法THP-1单核细胞株经佛波酯诱导分化为巨噬细胞。用不同浓度C反应蛋白或高密度脂蛋白在体外干预巨噬细胞,测定干预前后巨噬细胞血凝素样氧化型低密度脂蛋白受体1蛋白和mRNA表达的变化,并采用高效液相色谱测定巨噬细胞内胆固醇含量的变化。结果与对照组相比,C反应蛋白或高密度脂蛋白均可以诱导THP-1来源的巨噬细胞血凝素样氧化型低密度脂蛋白受体1蛋白和mRNA表达增加(P<0.05),C反应蛋白使巨噬细胞内总胆固醇和胆固醇酯含量显著增加(P<0.01),而高密度脂蛋白使细胞内总胆固醇和胆固醇酯显著降低(P<0.01)。结论C反应蛋白和高密度脂蛋白都能引起THP-1来源的巨噬细胞表面血凝素样氧化型低密度脂蛋白受体1表达上调,提示血凝素样氧化型低密度脂蛋白受体1并不是介导巨噬细胞参与炎症反应病理生理变化的关键性受体。  相似文献   

8.
为探索巨噬细胞集落刺激因子,清道夫受体、氧化型低密度脂蛋白与动脉粥样硬化的关系,观察了重组人巨噬细胞集落刺激因子对小鼠腹腔巨噬细胞清道夫受体途径的影响以及重组人巨细胞内胆固醇酯积聚的影响。结果发现重组人巨噬细胞集落刺激因子能增加培养小鼠的腹腔巨噬细胞表面的清道夫受体数目,使之对氧化型低密度脂蛋白的结合和降解呈现剂量和时间依赖性增加,并使细胞内胆固醇酯积聚增多。  相似文献   

9.
目的 研究动脉粥样硬化过程中低密度脂蛋白免疫复合物对单核细胞源性巨噬细胞胆固醇代谢和低密度脂蛋白受体表达的影响。方法 以佛波酯刺激分化的THP-1细胞作为单核细胞源性巨噬细胞模型。通过胆固醇酶联法测定细胞内胆圊醇含量,逆转录-聚合酶链反应检测细胞低密度脂蛋白受体mRNA的表达,Western blot检测细胞低密度脂蛋白受体蛋白的表达。结果 与低密度脂蛋白组、阴性组及IgG免疫复合物组比较,低密度脂蛋白免疫复合物组细胞内胆固醇水平明显增高,并且低密度脂蛋白受体mRNA及蛋白的表达增加。结论 低密度脂蛋白免疫复合物能显著增加巨噬细胞内胆固醇含量,亦能够促进低密度脂蛋白受体mRNA与蛋白的表达,提示低密度脂蛋白免疫复合物在动脉粥样硬化进展过程中起重要的作用。  相似文献   

10.
用苏丹Ⅳ染色观察巨噬细胞内脂质聚积的变化;通过酶-荧光法检测巨噬细胞内胆固醇含量并检测125Ⅰ标记氧化型低密度脂蛋白降解量来反映巨噬细胞清道夫受体的活性,以探讨硫酸乙酸肝素蛋白聚糖及肝素对巨噬细胞脂质蓄积的影响及机制。结果发现,氧化型低密度脂蛋白(100mg/L)组巨噬细胞的胞浆内可见较多苏丹Ⅳ着色红染颗粒,氧化型低密度脂蛋白(100mg/L)十硫酸乙酰肝素蛋白聚糖(15.5mg/L)组0及氧化型低密度脂蛋白(100mg/L)十肝素(200mg/L)组巨噬细胞内红色颗粒明显少于氧化型低密度脂蛋白组;氧化型低密度脂蛋白十硫酸乙酰肝素蛋白聚糖组及氧化型低密度脂蛋白十肝素组巨噬细胞内总胆固醇和胆固醇酯的含量明显低于氧化型低密度脂蛋白组(P<0.05,P<0.01);硫酸乙酰肝素蛋白聚糖组及肝素组125Ⅰ标记的氧化型低密度脂蛋白降解量均低于对照组。结果提示,硫酸乙酰肝素蛋白聚糖和肝素可能是通过下调清道夫受体活性减少了巨噬细胞对氧化型低密度脂蛋白的摄取而抑制脂质在巨噬细胞内的聚集和泡沫细胞的形成。  相似文献   

11.
The immunoneuroendocrine role of melatonin   总被引:19,自引:0,他引:19  
Abstract: A tight, physiological link between the pineal gland and the immune system is emerging from a series of experimental studies. This link might reflect the evolutionary connection between self-recognition and reproduction. Pinealectomy or other experimental methods which inhibit melatonin synthesis and secretion induce a state of immunodepression which is counteracted by melatonin. In general, melatonin seems to have an immunoenhancing effect that is particularly apparent in immunodepressive states. The negative effect of acute stress or immunosuppressive pharmacological treatments on various immune parameters are counteracted by melatonin. It seems important to note that one of the main targets of melatonin is the thymus, i.e., the central organ of the immune system. The clinical use of melatonin as an immunotherapeutic agent seems promising in primary and secondary immunodeficiencies as well as in cancer immunotherapy. The immunoenhancing action of melatonin seems to be mediated by T-helper cell-derived opioid peptides as well as by lymphokines and, perhaps, by pituitary hormones. Melatonin-induced-immuno-opioids (MHO) and lymphokines imply the presence of specific binding sites or melatonin receptors on cells of the immune system. On the other hand, lymphokines such as -γ-interferon and interleukin-2 as well as thymic hormones can modulate the synthesis of melatonin in the pineal gland. The pineal gland might thus be viewed as the crux of a sophisticated immunoneuroendocrine network which functions as an unconscious, diffuse sensory organ.  相似文献   

12.
Abstract: The abundance of gap junctions between rat pineal astrocytes formed by connexin43 (Cx43) was studied during development. Levels and distribution of Cx43 were measured by immunoblotting and indirect immunofluorescence, respectively. The amount of Cx43 in cells located within the gland was low until about the 7th postnatal day and increased to adult values between the 14th and 21st days postpartum. Although astrocytes, recognized by their vimentin immunoreactivity, were scarce before birth, they were abundant by the 7th postnatal day suggesting that the low levels of Cx43 found at this age corresponded to a low expression of this protein. Localization of the immunoreactivity to Cx43 and vimentin showed a close correlation, indicating that mature or immature pineal astrocytes form gap junctions made of Cx43. Since Cx43 levels attained their adult values at about the time the innervation and the functional state of the gland reached maturity (2–3 weeks after birth), it is proposed that astrocyte gap junctions are involved in the function of the adult rat pineal gland.  相似文献   

13.
Duodenal diverticula are a relatively common condition. They are asymptomatic, unless they become complicated, with perforation being the rarest but most severe complication. Surgical treatment is the most frequently performed approach. We report the case of a patient with a perforated duodenal diverticulum, which was diagnosed early and treated conservatively with antibiotics and percutaneous drainage of secondary retroperitoneal abscesses. We suggest this method could be an acceptable option for the management of similar cases, provided that the patient is in good general condition and without septic signs.  相似文献   

14.
15.
Abstract: The use of antisera raised against bovine growth hormone (GH) and ovine prolactin (PRL) enabled the detection of related immunoreactive (ir) sequences of proteins in ovine pineal tissue. The isolation of PRL-like ir-material was accomplished using a 0.25 M ammonium sulphate (pH 5.5) extraction followed by ethanol precipitation, whereas the resulting 2.0 M ammonium sulphate (pH 7.0) precipitate contained a GH-like immunoreactivity. Gel chromatography of the GH-like immunoreactivity (Sephadex G-100) indicated the presence of several GH-like fragments ranging in the Mr range of 7,000 to 55,000. Analyses of the PRL-like ir-material found in pineal tissue on HPLC using a TSK 545-DEAE column led to the resolution into a single peak of immunoreactivity. A single peak of activity was also observed following chromatofocusing and hydrophobic interaction chromatography of the ir-peak from the TSK 545-DEAE column. The PRL-like ir-material inhibited the binding of [125I]ovine PRL-S14 to anti-ovine PRL antibodies without showing an affinity for binding to anti-rat PRL or anti-bovine GH antibodies. Scatchard analysis of the binding of pineal PRL-like ir-material and pituitary ovine PRL-S14 to liver membranes from day-20 pregnant rats revealed similar affinity constants (Ka of 4.7 ± 0.2 × 109 M-1). In addition, the replication of Nb 2 Node rat lymphoma cells was stimulated by pineal PRL-like ir-material, an effect known to be specific for lactogenic hormones. The pineal PRL-like immunoreactivity appeared on sodium dodecyl sulfate polyacrylamide gels as a single major band of Mr 24,000. The functional status of PRL-and GH-like ir-material in the ovine pineal remains to be determined, but evidence is presented that the overall protein synthesis rate of the rat pineal responded to circulating concentrations of PRL.  相似文献   

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18.
AIM: To evaluate the effectiveness and safety of oral N-acetyl-L-cysteine (NAC) co-administration with mesalamine in ulcerative colitis (UC) patients.
METHODS: Thirty seven patients with mild to moderate UC were randomized to receive a four-wk course of oral mesalamine (2.4 g/d) plus N-acetyl-L-cysteine (0.8 g/d) (group A) or mesalamine plus placebo (group B). Patients were monitored using the Modified Truelove-Witts Severity Index (MTWSI). The primary endpoint was clinical remission (MTWSI ≤ 2) at 4 wk. Secondary endpoints were clinical response (defined as a reduction from baseline in the MTWSI of ≥ 2 points) and drug safety. The serum TNF-α, interleukin-6, interleukin-8 and MCP-1 were evaluated at baseline and at 4 wk of treatment. RESULTS: Analysis per-protocol criteria showed clinical remission rates of 63% and 50% after 4 wk treatment with mesalamine plus N-acetyl-L-cysteine (group A) and mesalamine plus placebo (group B) respectively (OR = 1.71; 95% CI: 0.46 to 6.36; P = 0.19; NNT = 7.7). Analysis of variance (ANOVA) of data indicated a significant reduction of MTWSI in group A (P = 0.046) with respect to basal condition without significant changes in the group B (P = 0.735) during treatment. Clinical responses were 66% (group A) vs 44% (group B) after 4 wk of treatment (OR = 2.5; 95% CI: 0.64 to 9.65; P = 0.11; NNT = 4.5). Clinical improvement in group A correlated with a decrease of IL-8 and MCP-1. Rates of adverse events did not differ significantly between both groups.
CONCLUSION: In group A (oral NAC combined with mesalamine) contrarily to group B (mesalamine alone), the clinical improvement correlates with a decrease of chemokines such as MCP-1 and IL-8. NAC addition not produced any side effects.  相似文献   

19.
Surgical therapy of functional outlet obstruction in patients with internal rectal intussusception may include abdominal, perineal, or transrectal procedures. Because abdominal procedures often result in significant physiologic impact but unrelieved constipation, the authors have elected Delorme's transrectal excision for management of these patients. Since a short-term placebo effect attends many therapies, this report describes results of transrectal excision only after a threeyear postoperative period. Delorme's transrectal excision of internal intussusception accomplished sustained symptomatic relief in over 70 percent of otherwise refractory constipated patients. The association of internal intussusception with other abnormalities underscores the importance of defining both anatomic and functional components when selecting patients whose constipation may require surgical therapy. Critical technical elements, surgical pitfalls, and potential complications of the procedure are discussed.Poster presentation at the meeting of The American Society of Colon and Rectal Surgeons, Toronto, Canada, June 11 to 16, 1989.  相似文献   

20.
Summary Time points in the glucose tolerance test (GTT) are compared on the basis of limit values, dispersion within a reference population, and reproducibility. We suggest using the distance between a limit value and the median reference value as a measure of the magnitude of abnormality. The distance between 140 mg/100 ml and the median fasting plasma glucose value is chosen as a standard distance and limits for other points in the GTT are calculated to equal this standard distance of abnormality. We suggest that the probability of correctly interpreting an inividual result is directly related to the reproducibility of the test and inversely related to the percentage of the total range of values which is dispersed among the normal population. The ratio of reproducibility to percentage normal dispersion is proposed as an index of the probability of correctly interpreting an individual result. According to this index, the probability of correct interpretation varies in order: fasting plasma glucose concentration>3-h>2-h>0.5-h>1-h plasma glucose concentration.  相似文献   

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