重组基质细胞衍生因子1α对单核细胞的趋化作用

目的探讨pcDNA3.1-基质细胞衍生因子1α重组质粒对单核细胞的趋化作用。方法将pcDNA3.1-基质细胞衍生因子1α质粒用脂质体的方法导入人脐静脉内皮细胞株ECV304细胞中,G418筛选细胞克隆。通过逆转录聚合酶链反应法在转录水平检测基质细胞衍生因子1α在转基因ECV304细胞中的表达。通过Transwell实验研究基质细胞衍生因子1α对单核细胞的趋化作用。结果获得了稳定表达基质细胞衍生因子1α基因的ECV304细胞克隆,pcDNA3.1-基质细胞衍生因子1α重组质粒对单核细胞具有趋化作用。结论重组大鼠基质细胞衍生因子1α对单核细胞具有明显的趋化作用。     

基质细胞衍生因子1α通过上调CXCR4表达促进单核—内皮细胞粘附

目的研究基质细胞衍生因子1α对CXCR4表达及THP-1单核细胞与内皮细胞粘附的影响。方法逆转录聚合酶链反应检测CXCR4 mRNA的表达,免疫印迹检测其蛋白表达变化;用0、50、100和200μg/L基质细胞衍生因子1α处理内皮细胞30min后,将THP-1单核细胞与内皮细胞共孵育后洗脱检测THP-1与内皮细胞的粘附,并加用10mg/L的CXCR4抗体阻断。结果100μg/L基质细胞衍生因子1α显著上调THP-1单核细胞上CXCR4的表达(P<0.05),基质细胞衍生因子1α能促进内皮细胞与THP-1单核细胞的粘附,且随着作用浓度的增加粘附细胞数也增加,但可被CXCR4抗体所抑制。结论基质细胞衍生因子1α可上调THP-1单核细胞上CXCR4表达,并能促单核细胞与内皮细胞粘附,其机制与上调单核细胞CXCR4表达有关。     

基质细胞衍生因子1α对氧化型低密度脂蛋白诱导内皮细胞与单核细胞粘附的影响

目的观察基质细胞衍生因子1α对氧化型低密度脂蛋白诱导的单核细胞与内皮细胞粘附的影响。方法逆转录聚合酶链反应法和免疫印迹法分别检测内皮细胞基质细胞衍生因子1αmRNA和蛋白的表达,静态粘附实验观察氧化型低密度脂蛋白和基质细胞衍生因子1α抗体干预对内皮细胞与单核细胞粘附的影响。结果基质细胞衍生因子1α在静息状态下的血管内皮细胞上几乎不表达,随着氧化型低密度脂蛋白浓度增加和处理时间延长,基质细胞衍生因子1α的mRNA和蛋白表达水平均明显上调,25mg/L氧化型低密度脂蛋白处理48h时,基质细胞衍生因子1α表达到达峰值。氧化型低密度脂蛋白浓度为1、5、25及125mg/L时,每个视野粘附的单核细胞数分别为190±15、226±23、280±14、253±8,而正常对照组为104±10,差异有显著性意义(P<0.05)。终浓度为0.01、0.1和1μg/L基质细胞衍生因子1α抗体干预后,粘附的单核细胞数分别为202±17、142±6和115±12,明显低于对照组的279±11(P<0.05)。结论基质细胞衍生因子1α参与了内皮细胞与单核细胞的粘附。     

基质细胞衍生因子1α—CXCR4趋化THP-1细胞迁移及氧化型低密度脂蛋白的影响

目的探讨基质细胞衍生因子1α对单核细胞趋化作用、氧化型低密度脂蛋白对基质细胞衍生因子1α趋化单核细胞的影响及其对THP-1细胞表达CXCR4的影响。方法用Transwell迁移实验检测基质细胞衍生因子1α对单核细胞的趋化作用，逆转录聚合酶链反应检测CXCR4 mRNA的表达，Westem blot检测CXCR4蛋白的表达，并观察氧化型低密度脂蛋白对THP-1细胞CXCR4表达的剂量和时间效应。结果基质细胞衍生因子1α呈浓度依赖性诱导单核细胞迁移，加入CXCR4抗体可明显抑制这种作用。经不同浓度氧化型低密度脂蛋白处理48h后的THP-1细胞再用10μg/L基质细胞衍生因子1α进行趋化时，氧化型低密度脂蛋白呈浓度依赖性地增加单核细胞的迁移，50mg／L氧化型低密度脂蛋白组迁移的细胞数是对照组的11倍。THP-1细胞有基础水平的CXCR4表达，50mg／L氧化型低密度脂蛋白可使CXCR4的表达上调4．5倍。CXCR4上调最早在6h内发生，12h达峰值。结论基质细胞衍生因子1α--CXCR4参与趋化单核细胞迁移，其作用被氧化型低密度脂蛋白加强；氧化型低密度脂蛋白上调CXCR4表达。     

基质细胞衍生因子1对低密度脂蛋白诱导单核—内皮细胞粘附的影响

目的观察基质细胞衍生因子1对低密度脂蛋白诱导的单核细胞-内皮细胞粘附的调节作用,以进一步探讨基质细胞衍生因子1在动脉粥样硬化中的作用。方法密度梯度离心法分离人低密度脂蛋白;逆转录聚合酶反应检测内皮细胞基质细胞衍生因子1mRNA表达,Westernblot检测基质细胞衍生因子1蛋白质的表达;细胞记数法观察低密度脂蛋白及基质细胞衍生因子1抗体干预对内皮细胞单核细胞粘附的影响。结果对照组几乎没有基质细胞衍生因子mRNA以及蛋白质的表达,随着低密度脂蛋白浓度增加,基质细胞衍生因子1mRNA以及蛋白质的表达水平明显增加。低密度脂蛋白浓度为50mgL、100mgL和150mgL时,每个视野粘附的单核细胞数分别为60±20、97±26和170±32,而正常对照组为20±5,差异有极显著性意义(P<0.01)。终浓度为0.1mgL、0.5mgL和1mgL基质细胞衍生因子1抗体干预后,粘附的单核细胞数分别为113±23、53±21和41±10,均低于低密度脂蛋白对照组的186±31,与低密度脂蛋白对照组差异有显著性意义(P<0.05)。结论低密度脂蛋白促进内皮细胞与单核细胞的粘附,其机制与促进内皮细胞表达基质细胞衍生因子1密切相关。     

基质细胞衍生因子1α对大鼠血管平滑肌细胞与单核细胞粘附的影响

目的探讨基质细胞衍生因子1α对大鼠血管平滑肌细胞与单核细胞粘附的影响。方法原代培养的大鼠血管平滑肌细胞与50mg/L氧化型低密度脂蛋白孵育48h,将单核细胞与平滑肌细胞共孵育后洗脱检测粘附功能,并用基质细胞衍生因子1α抗体阻断。结果经氧化型低密度脂蛋白处理的血管平滑肌细胞基质细胞衍生因子1α上调5倍,单核细胞粘附增加29倍,但可被基质细胞衍生因子1α单抗所阻断。结论基质细胞衍生因子1α参与单核细胞与大鼠血管平滑肌细胞的粘附过程。     

晚期氧化蛋白产物通过p38丝裂原活化蛋白激酶通路促进ECV304细胞基质细胞衍生因子1α的表达

目的观察晚期氧化蛋白产物对ECV304细胞基质细胞衍生因子1α表达的影响,并探讨其作用机制。方法牛血清白蛋白与次氯酸钠等量混合体外制备晚期氧化蛋白产物,RT-PCR法检测ECV304细胞基质细胞衍生因子1αmRNA的表达,Western Blotting法测定基质细胞衍生因子1α以及磷酸化p38丝裂原活化蛋白激酶(p-p38MAPK)蛋白水平,以p38MAPK特异性阻断剂SB203580进行阻断实验,酶联免疫吸附法测定上清液中基质细胞衍生因子1α浓度。结果与对照组比较,200μmol/L晚期氧化蛋白产物处理ECV304细胞2h后基质细胞衍生因子1αmRNA及蛋白表达量显著升高(P均0.05);基质细胞衍生因子1αmRNA表达量6h达高峰(P0.01),之后逐渐下降,24h时与对照组比较差异无显著性;随时间的推移基质细胞衍生因子1α蛋白表达量逐渐升高,24h表达量最高(P0.01)。晚期氧化蛋白产物作用15min后p38丝裂原活化蛋白激酶磷酸化水平明显增强(P0.05),不同浓度(0.1μmol/L、1μmol/L、10μmol/L)SB203580降低了晚期氧化蛋白产物刺激下基质细胞衍生因子1α蛋白的表达(分别为618.85±60.12、500.98±69.47和359.97±59.81,P0.05或0.01)。结论晚期氧化蛋白产物可诱导ECV304细胞基质细胞衍生因子1α表达,p38MAPK通路是介导这一作用的重要途径之一。     

单核—巨噬细胞和ECV304内皮细胞表达死亡相关蛋白

为研究单核——巨噬细胞和ECV304细胞是否表达死亡相关蛋白以及影响死亡相关蛋白表达的因素。分别用氧化型低密度脂蛋白(100mg／L)孵育THP-1细胞，H2O2(1mmol／L)孵育ECV304细胞，用逆转录聚合酶链反应检测死亡相关蛋白mRNA的表达。结果发现，THP-1细胞及ECV304细胞均表达死亡相关蛋白，氧化型低密度脂蛋白和H2O2能分别诱导THP-1细胞和ECV304细胞死亡相关蛋白mRNA表达增高。实验结果提示死亡相关蛋白可能参与调节氧化应激诱导的单核—巨噬细胞和内皮细胞的凋亡。     

重组腺病毒IκBαM抑制高糖诱导的血管内皮细胞炎症因子的异常分泌

构建携有核因子κB抑制物IκBα的突变体IκBαM的重组腺病毒(AdIκBαM)，并感染ECV304血管内皮细胞，采用Westem blot、电泳迁移率变动分析和逆转录-聚合酶链反应等方法研究核因子κB在高浓度葡萄糖刺激的ECV304细胞分泌功能中所起的作用以及阻断其活性对内皮细胞分泌功能的影响。结果发现，高糖能诱导ECV304细胞IκBa的降解和核因子κB的激活，同时上调炎症因子细胞间粘附分子1、单核细胞趋化蛋白1和内皮素1mRNA表达水平，而感染AdlIκBαM的ECV304／IκBαM细胞则能拮抗高糖所致的IκBα降解与核因子κB激活，同时下调这些炎症因子的异常分泌水平。结果提示，核因子κB的激活在高糖所致的内皮细胞分泌功能改变中起中轴作用，抑制核因子κB的活化，有助于改善血管内皮细胞功能。     

一氧化氮对肿瘤坏死因子-α诱导的大鼠血管平滑肌细胞细胞间粘附分子-1表达的影响

为探讨肿瘤坏死因子－α介导单核细胞与血管平滑肌细胞粘附致动脉 粥样硬化及一氧化氮抗动脉粥样硬化的机制,用体外培养的大鼠血管平滑肌细胞,以硝普钠为一氧化氮供体,采用细胞粘附实验,流式细胞术和逆转录－聚合酶链反应观察一氧化氮对肿瘤坏死因子－α诱导的细胞间粘附分子－1在血管平滑肌细胞中的表达及其对单核细胞与血管平滑肌细胞粘附的影响。结果发现一氧化氮显著抑制肿瘤坏死因子－α诱导的单核细胞与血管平滑肌细胞的粘附及细胞间粘附分子－1在血管平滑肌细胞中的表达,减少血管平滑肌细胞表面的细胞间粘附分子－1,结果表明一氧化氮抑制细胞间粘附分子－1基因表达及降低单核细胞与血管平滑肌细胞之间的粘附率是其抗动脉粥样硬化的机制之一。     

The immunoneuroendocrine role of melatonin

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.     

Changes in connexin43, the gap junction protein of astrocytes, during development of the rat pineal gland

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.     

Conservative management of perforated duodenal diverticulum： A case report and review of the literature

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.     

Response of rat pineal melatonin to calcium, magnesium, and lithium is circadian stage dependent

Abstract: Herein we documented the response of pineal melatonin production to electrolytes known to be effective on pineal function in view of a possible circadian stage dependence. We studied the release of melatonin by perifused rat pineal glands at 2 different circadian stages corresponding to the middle of the light and dark periods, i.e., respectively, 7 and 19 HALO (Hours After Light Onset, L:D = 12:12). The initial efflux rates were, as expected, much higher in the perifusates of glands removed from rats sacrificed during the dark phase than of those removed during the light phase. After 3 hr of perifusion, melatonin release reached similar levels which were found constant up to the 8th hr of perifusion, whatever the circadian stage. Perifusion of the glands with physiological concentrations for the rat of calcium (5.2 mmol/1) and magnesium (1.34 mmol/1) resulted in a stimulatory effect on the pineal glands removed from rats sacrificed in the middle of the dark period (19 HALO), whereas no effects were observed on the pineal glands removed from rats sacrificed during the light (7 HALO). Lithium (0.28 and 0.55 mmol/1) was ineffective on melatonin release in pineal glands removed 7 and 19 HALO. Our results show differences in the initial efflux rates of melatonin and in the response of perifused pineal glands to calcium and magnesium according to the circadian stage.     

Presence of immunoreactive growth hormone and prolactin in the ovine pineal gland

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 M_r 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 (K_a 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 M_r 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.     

Microbiology of human immunodeficiency virus anorectal disease

PURPOSE: Individuals who are seropositive for the human immunodeficiency virus are at high risk for opportunistic infection and anorectal disorders. Little prospective information is available regarding anorectal pathogens in these patients. METHODS: One hundred sixty-three HIV-seropositive patients presented to the colorectal clinic between 1989 and 1992. Forty-seven (29 percent) patients were thought to have an infectious process and were prospectively studied using a standardized multiculture protocol. RESULTS: Mean age was 33 (range, 19–59) years. All were male; high-risk behavior accounted for 87 percent of HIV transmissions. Presenting complaints included anorectal pain (79 percent), pus per anum (28 percent), and blood per anum (26 percent). Examination revealed perianal tenderness (60 percent), condyloma (38 percent), perianal ulcers (38 percent), and anal fissures (34 percent). Sixty-six sets of cultures were performed; 28 patients had one set, 15 had two sets, and 4 had three sets. Thirty-two of these 47 patients (68 percent) had positive cultures including herpes (50 percent), cytomegalovirus (25 percent),Neisseria gonorrhoeae (16 percent), chlamydia (16 percent), acidfast bacilli (2 percent), and others (9 percent). Six of 32 patients with positive cultures had more than one organism cultured. Sixteen (50 percent) patients with positive cultures were treated medically, 8 (25 percent) were treated surgically and 8 (25 percent) were treated with both modalities. Sixty-one procedures were performed on 17 patients for condylomata. Eighteen patients had 20 procedures for abscesses, 50 percent of whom had positive cultures for other than common bowel flora; all improved. Fourteen patients underwent 33 procedures for perianal fistulas.Mycobacterium fortuitum was cultured from one patient who required 13 procedures for abscesses and fistulas. Forty-five (96 percent) patients were followed for an average of 12.5 months ±2.9 SEM (range, 1–94 months). Symptoms were improved or resolved in 22 of 32 (69 percent) patients with positive cultures and in 11 of 13 (84 percent) with negative cultures. CONCLUSIONS: Specific pathogens may often be identified in human immunodeficiency virus-seropositive patients with anorectal disorders if aggressively sought. Although patients without specific pathogens identified may be expected to improve with planned empiric treatment, positive identification allows more directed therapy.