葡萄籽原花青素对AGEs诱导的内皮细胞分泌NO及ET-1的影响

目的观察葡萄籽原花青素（GSP）对糖基化终产物（AGEs）诱导的人脐静脉内皮细胞（HUVEC）一氧化氮（NO）、内皮素（ET-1）生成及其mRNA表达的影响。方法牛血清白蛋白（BSA）与葡萄糖在体外共同孵育以制备糖基化终产物（AGE-BSA），将培养的HUVEC与不同浓度的GSP（5、15、25μg/ml）预孵育4h，再加入200μg/mlAGE-BSA共同培养，分别用硝酸还原酶法及放免法测定培养上清液中NO及ET-1的含量，用逆转录PCR（RT-PCR）检测一氧化氮合酶（eNOS）及ET-1 mRNA的表达，用激光共聚焦显微镜检测细胞内活性氧簇（ROS）的产生。结果HUVEC用AGE-BSA刺激后明显增强细胞内ROS产生，并能减少内皮细胞NO的分泌及eNOS mRNA的表达，增加内皮细胞ET-1的分泌及其 mRNA的表达（P〈0.01）。而GSP预孵育则对AGE-BSA诱导的上述作用具有显著的改善作用，并呈剂量依赖性（P〈0.01）。结论GSP可能通过抑制细胞内氧化应激而影响AGEs诱导的内皮细胞NO及ET-1生成，改善血管内皮功能，这对于防治糖尿病慢性血管并发症具有重要的意义。     

氨基胍对糖基化终产物干预后人肾系膜细胞MMP-2表达的影响

目的观察盐酸氨基胍（AG）对糖基化终产物（AGEs）干预后人肾系膜细胞（HRMC）基质金属蛋白酶2（MMP-2）表达的影响。方法运用糖基化终产物-牛血清白蛋白（AGE-BSA）干预HRMC,以及不同浓度AG单独或与AGE-BSA共同干预HRMC24小时;RT-PCR和Western blot分别检测HRMC MMP-2mRNA和蛋白表达。结果AGE-BSA明显降低HRMC MMP-2mRNA和蛋白表达（P〈0.05）,AG以浓度依赖的方式恢复AGE-BSA下调的HRMC MMP-2mRNA和蛋白表达（P〈0.05）。结论AG可能通过拮抗AGEs对MMP-2表达的抑制效应而发挥其肾脏保护作用。     

糖基化终产物对U937细胞巨噬细胞炎性蛋白-1α mRNA表达的影响

目的探讨糖基化终产物(AGEs)对U937细胞巨噬细胞炎性蛋白-1αmRNA表达的影响,及AGEs在糖尿病动脉粥样硬化中的作用。方法将U937细胞用不同浓度(100、200、400 mg/L)AGEs孵育24 h及同一浓度(400 mg/L)AGEs孵育0、12、24及36 h,采用原位杂交(PT-PCR)方法检测巨噬细胞炎性蛋白-1αmRNA的表达水平。结果对照组U937细胞内巨噬细胞炎性蛋白-1α呈弱表达;100、200及400 mg/LAGEs孵育24 h后,各组U937细胞内巨噬细胞炎性蛋白-1αmRNA表达的平均积分光密度值较对照组均显著升高(P<0.05);400 mg/L AGEs孵育12、24及36 h后,各组U937细胞内巨噬细胞炎性蛋白-1αmRNA表达的平均积分光密度值均高于0 h(P<0.05)。结论AGEs以时间及剂量依赖的方式促进U937细胞巨噬细胞炎性蛋白-1αmRNA的表达。     

格列喹酮对糖基化终产物诱导的人肾系膜细胞RANTES表达的影响

目的探讨格列喹酮对糖基化终产物（AGEs）诱导的人肾系膜细胞（HRMC）正常T细胞表达分泌的调节活化蛋白（RANTES）表达的影响。方法运用糖基化修饰的牛血清白蛋白（AGE-BSA）和格列喹酮干预体外培养的HRMC,用半定量RT-PCR检测细胞中RANTES mRNA水平,用ELISA法测定细胞培养上清中RANTES蛋白水平。结果格列喹酮干预组HRMC RANTES的mRNA表达和蛋白分泌低于AGE-BSA组（P〈0.05）,且降低水平呈浓度和时间依赖性。结论格列喹酮能抑制糖基化终产物诱导的HRMC RANTES的表达和分泌。     

缬沙坦抑制非对称二甲基精氨酸诱导的内皮细胞LOX-1的表达

目的 研究缬沙坦对非对称二甲基精氨酸(ADMA)诱导的人脐静脉内皮细胞(HUVEC)凝集素样氧化型低密度脂蛋白受体1 (LOX-1) mRNA和蛋白表达的影响,并探讨其机制.方法 体外培养HUVEC,以不同浓度的缬沙坦和15 μmol/L ADMA共同孵育24h,DCFH-DA检测细胞内活性氧(ROS)生成量；RT-PCR测定NADPH氧化酶p22phox及LOX-1 mRNA的转录水平；酶联免疫吸附法检测细胞LOX-1蛋白的表达水平.结果 与ADMA组相比,缬沙坦干预后细胞ROS水平显著下降(P＜0.05),p22phox和LOX-1 mRNA转录水平及LOX-1蛋白的表达水平明显下调(P＜0.05),并呈剂量依赖性.结论 缬沙坦通过抑制p22phox的表达减少细胞内ROS水平,进而抑制ADMA诱导的内皮细胞LOX-1 mRNA转录和蛋白表达,这可能是其独立于降压作用的抗动脉粥样硬化作用的部分机制.     

辛伐他汀抑制糖基化终产物诱导心肌微血管内皮细胞炎性反应及机制探讨

目的观察羟甲基戊二酰辅酶A还原酶抑制荆辛伐他汀对糖基化终产物(AGEs)诱导心肌微血管内皮细胞(CMECs)表达单核细胞趋化因子1(MCP-1)、细胞间黏附分子1(ICAM-1)的抑制作用,探讨辛伐他汀在早期糖尿病心肌微血管炎性病变中的保护机制。方法将培养的CMECs用辛伐他汀预孵育6 h,加入400mg/L的外源性糖基化牛血清白蛋白共培养72 h,分为AGEs组和BSA对照组,分别采用ELISA法测定McP-1的表达;流式细胞仪测定ICAM-1的表达;RT-PCR法测定糖基化终产物特异性受体mRNA的表达;Western blot法检测内皮细胞表面特异性受体(RAGE)蛋白表达。结果与BSA对照组比较,AGEs组MCP-1、ICAM-1、RAGE mRNA及其蛋白表达明显增强,差异有统计学意义(P<0.05)。辛伐他汀预孵则显著抑制AGEs诱导的MCP-1、ICAM-1的表达,并在mRNA及蛋白水平下调RAGE蛋白的表达。结论辛伐他汀可能通过抑制AGEs-RAGE信号途径来发挥对糖尿病心肌微血管病变的保护作用。     

马来酸罗格列酮抑制糖基化终产物诱导的人肾系膜细胞RANTES高表达

目的探讨马来酸罗格列酮对糖基化终产物（AGEs）诱导的人肾系膜细胞（HRMC）趋化因子RANTES高表达的影响,及其对糖尿病大鼠血清糖基化终产物-肽（AGE-P）及肾脏RANTES表达的影响。方法运用糖基化修饰的牛血清白蛋白（AGE-BSA）与马来酸罗格列酮干预体外培养的HRMC,EusA法检测细胞培养上清中RANTEs蛋白水平,实时定量RT-PCR检测细胞中RANTES mRNA水平,Western blot检测RANTES蛋白表达。制备2型糖尿病大鼠模型,马来酸罗格列酮治疗10周。流动注射分析法测定血清AGEP,免疫组织化学检测肾皮质RANTES表达。结果马来酸罗格列酮干预组HRMC RANTES的mRNA和蛋白表达以及蛋白分泌明显低于AGE-BSA组;马来酸罗格列酮治疗组糖尿病大鼠血清AGE-P明显下降,肾皮质RANTES表达明显低于糖尿病非治疗组。结论马来酸罗格列酮可以抑制AGE-BSA诱导的HRMC RANTES的表达和分泌,还可降低糖尿病大鼠血清AGE-P及肾脏RANTES表达。     

糖基化终产物对大鼠主动脉平滑肌细胞巨噬细胞炎性蛋白-1α表达的影响

目的　探讨糖基化终产物 (AGEs)对大鼠主动脉平滑肌细胞巨噬细胞炎性蛋白 1α(MIP 1α)mRNA及蛋白表达的影响。　方法　将培养的大鼠主动脉平滑肌细胞用不同浓度 (10 0、2 0 0、4 0 0mg/L)的AGEs孵育 2 4h及同一浓度 (4 0 0mg/L)AGEs孵育 0、12、2 4、36h ,采用RT PCR方法及流式细胞仪检测MIP 1αmRNA及蛋白的表达水平。　结果　对照组平滑肌细胞内MIP 1α呈弱表达 ,10 0、2 0 0、4 0 0mg/LAGEs培养平滑肌细胞 2 4h显著增高MIP 1αmRNA的表达 ,其电泳条带相对积分吸光度值分别为对照组的 1 36、1 75、2 4 5倍 (P <0 0 5 ) ;10 0、2 0 0、4 0 0mg/LAGEs孵育2 4h后 ,各组平滑肌细胞MIP 1α蛋白的平均荧光强度分别为 197± 3、2 6 0± 6及 375± 6 ,分别为对照组(15 8± 4 )的 1 2 4、1 6 3、2 37倍 (P <0 0 5 )。 4 0 0mg/LAGEs培养 12、2 4、36h后 ,各组平滑肌细胞MIP 1αmRNA的表达也明显增高 ,其电泳条带相对积分吸光度值分别为 0h组的 1 5 2、2 38、2 5 3倍(P <0 0 5 ) ;4 0 0mg/LAGEs孵育 12、2 4、36h后 ,各组平滑肌细胞MIP 1α蛋白的平均荧光强度分别为 2 4 4± 5、375± 6及 4 2 5± 3,分别为 0h组 (170± 5 )的 1 4 3、2 2 1、2 4 9倍 (P <0 0 5 )。　结论　糖基化终产物以时间及剂量     

外源性硫化氢对氧化型低密度脂蛋白诱导组织因子和组织因子途径抑制物表达的影响

目的研究外源性硫化氢对氧化型低密度脂蛋白(ox-LDL)诱导内皮细胞组织因子(TF)和组织因子途径抑制物(TFPI)表达的影响。方法培养人脐静脉内皮细胞(HUVEC),分别以不同浓度NaHS(25、50、100及200μmol/L)和50 mg/L ox-LDL共孵育,RT-PCR和ELISA分别检测TF和TFPI mRNA表达和蛋白含量。结果用50mg/L ox-LDL孵育HUVEC 24 h后,TF mRNA表达上调8倍,蛋白含量增加7倍(P<0.01);而TFPI mRNA表达降低73%,蛋白含量减少65%(P<0.01)。用25、50、100及200μmol/L NaHS预孵育HUVEC 1 h,再与ox-LDL共同孵育,与ox-LDL组相比,加入不同浓度NaHS组TF mRNA分别降低12%、31%、63%和80%(P<0.05),蛋白含量分别降低13%、30%、62%和77%;TFPI mRNA表达分别升高0.6、1.2、2.0和2.6倍,蛋白含量分别升高0.3、0.7、1.1和1.6倍。结论 NaHS能抑制ox-LDL对内皮细胞TF表达的诱导作用,减轻ox-LDL对内皮细胞TFPI表达的抑制作用。     

糖化终末产物对INS-1细胞基质金属蛋白酶2表达的影响

目的 探讨糖化终末产物(AGEs)对大鼠胰岛细胞株INS-1基质金属蛋白酶2(MMP-2)表达量的影响.方法 培养INS-1细胞,检测MMP-2表达;制备糖化胎牛血清,通过流式细胞仪检测细胞内活性氧簇(ROS)水平,通过逆转录PCR、实时定量PCR和Western印迹方法观察细胞中MMP-2表达量的变化.结果 INS-1细胞中存在MMP-2的表达;AGEs刺激后ROS明显升高(P<0.05),刺激组细胞内MMP-2mRNA表达量和蛋白表达水平均显著高于对照组(P<0.05).结论 提示胰岛β细胞内存在MMP-2表达,AGEs可诱导β细胞MMP-2表达量增高,MMP-2在介导胰岛氧化应激损伤中可能起着重要作用.     

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.     

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.     

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.     

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.