内皮素-1对缺氧/复氧所致心肌细胞凋亡的影响

目的探讨在缺氧/复氧过程中不同时期给予内皮素-1（ET-1）对缺氧/复氧所致心肌损伤与凋亡的影响。方法乳鼠心肌细胞缺氧/复氧模型,流式细胞仪检测心肌细胞凋亡,Hoechst 33258染色计算凋亡率,试剂盒检测乳酸脱氢酶（LDH）的活性。结果ET-1预处理组（EP）细胞生存率较缺氧复氧组（HR）提高,凋亡率下降,LDH活性下降;ET-1缺氧即刻处理组（EH）细胞生存率较HR组降低,凋亡率升高,LDH释放量增加;ET-1复氧处理组（ER）的细胞生存率、凋亡率及LDH活性与HR组均无统计学差异。结论ET-1预处理有心肌细胞保护作用,ET-1缺氧时有促进心肌细胞损伤和凋亡的作用。     

参附注射液对原代培养乳鼠心肌细胞缺氧一复氧损伤的影响

目的探讨参附注射液（SFI）对原代培养的乳鼠心肌细胞缺氧／复氧损伤的保护作用及其机制。方法建立大鼠心肌细胞原代培养缺氧／复氧损伤模型,将培养心肌细胞随机分为4组。正常对照组（C组）;缺氧／复氧组（H／R组）;低浓度SFI处理组（SFI-L组）：加入终浓度为50tlmol／mLSFI30min后再缺氧／复氧;D组：高浓度SFI处理组（SFI-H组）：加入终浓度为1（）（]umol／mI。参附注射液30rain后再缺氧／复氧。检测各组上清液中肌酸激酶同工酶（CK-MB）、心肌肌钙蛋白I（cTn-I）含量,心肌细胞内丙二醛（MDA）含量和超氧化物歧化酶（SOD）活性以及心肌细胞凋亡指数。结果与C组比较,H,0R组心肌细胞培养液cK-MB、cTn-I含量、心肌细胞内MDA含量以及凋亡指数显著上升,SOD活性显著下降,差异有统计学意义（P〈0．01）。与H／R组比较,SFI-L组、SFI-H组中除SOD活性显著上升外,上述其他指标均显著下降,差异有统计学意义（P〈0．01）。结论SFI对缺氧／复氧损伤心肌细胞具有保护作用,其具体机制可能是与通过抑制脂质过氧化程度,减少心肌细胞凋亡有关。     

ERK1/2信号通路介导心肌营养素1对心肌细胞缺氧复氧损伤的保护作用

目的探讨心肌营养素1对心肌缺氧复氧损伤的保护作用及其信号通路。方法用改良的方法培养出生1～3天的乳鼠心肌细胞,分为五组:对照组、缺氧复氧组、缺氧复氧+心肌营养素1组、缺氧复氧+心肌营养素1+PD98059(ERK阻断剂)组及缺氧复氧+心肌营养素1+DMSO组。缺氧3 h,复氧3 h。MTS法测定心肌细胞存活率,四氯四乙基苯丙咪唑基羰化青碘化物(JC1)检测心肌细胞线粒体膜电位,二氯荧光磺双乙酸盐(DCFH-CA)检测细胞活性氧水平,流式细胞仪检测心肌细胞凋亡率,RT-PCR检测心肌细胞促凋亡基因Bad mRNA表达,Western blot检测ERK1/2蛋白水平。结果缺氧复氧后心肌细胞凋亡率及细胞内活性氧水平较对照组明显增加,分别是19.4%±2.3%比2.2%±0.2%及14.28±1.42比3.54±0.46(P<0.05),而心肌细胞存活率显著降低,心肌细胞线粒体膜电位下降。而心肌营养素1处理后,心肌细胞存活率明显高于缺氧复氧组,心肌细胞凋亡率及细胞内活性氧水平显著减少,心肌细胞线粒体膜电位更高,ERK1/2磷酸化蛋白水平增加,Bad mRNA表达明显下调。心肌营养素1的这种作用能被ERK阻断剂PD9...     

缺氧后处理与氧自由基清除剂预处理对心肌细胞膜和线粒体Bcl-2和Bax表达的影响

目的观察缺氧后处理与氧自由基清除剂超氧化物歧化酶(SOD)联合过氧化氢酶(CAT)预处理,对心肌细胞膜和线粒体Bcl-2、Bax蛋白表达的影响,探讨两者调控心肌细胞凋亡的机制。方法建立乳鼠心肌细胞缺氧/复氧损伤模型,分对照组、缺氧/复氧组、缺氧后处理组及缺氧/复氧+SOD+CAT组。应用荧光探针测定心肌细胞线粒体活性氧水平,Hoechst染色及流式细胞仪检测心肌细胞凋亡,Wesiern blot法检测心肌细胞膜和线粒体Bcl-2、Bax蛋白表达。结果与对照组比较,缺氧/复氧组、缺氧后处理组、缺氧/复氧+SOD+CAT组细胞线粒体活性氧及细胞凋亡率明显升高(P<0.01);与缺氧/复氧组比较,缺氧后处理组、缺氧/复氧+SOD+CAT组细胞线粒体活性氧及细胞凋亡率明显降低(P<0.01);缺氧后处理组及缺氧/复氧+SOD+CAT组细胞膜和线粒体Bcl-2蛋白明显上调,Bax蛋白明显下调。结论缺氧后处理及氧自由基清除剂预处理抑制线粒体活性氧爆发,减轻缺氧/复氧再灌注心肌细胞凋亡,其抗凋亡可能机制与细胞膜和线粒体Bcl-2蛋白表达上调及Bax蛋白表达下调有关。     

microRNA-1对心肌缺氧复氧中细胞凋亡的影响

目的明确心肌缺氧复氧(H/R)时miR-1的表达变化及其对细胞凋亡的影响。方法建立乳大鼠心肌细胞H/R模型,TUNEL检测细胞凋亡、Western-Blot检测凋亡蛋白表达和实时荧光定量PCR检测miR-1表达。重组miR-1慢病毒感染乳大鼠心肌细胞,Western-Blot检测各组相关凋亡蛋白的表达。重组miR-1慢病毒感染乳大鼠心肌细胞后H/R处理,通过TUNEL检测心肌细胞凋亡,软件分析和计算心肌细胞凋亡率。结果心肌细胞H/R后,细胞凋亡率明显增加,同时促凋亡蛋白(Bax和Caspase-3)表达水平增加和抗凋亡蛋白Bcl-2表达水平下降。在成功构建心肌细胞缺氧复氧细胞模型后,检测到心肌细胞miR-1表达水平下降。与对照组相比,感染LV-rno-miR-1组促凋亡蛋白(Bax和Caspase-3)明显增加和抗凋亡蛋白Bcl-2降低,而感染LV-rno-miR-1 sponge凋亡蛋白的结果相反。相对于感染LV-rnomiR-1组和缺氧复氧组,感染LV-rno-miR-1病毒后缺氧4小时复氧12小时,细胞凋亡率进一步增加。结论 miR-1具有促进细胞凋亡的作用。miR-1表达下降可能是心肌细胞缺氧复氧时维持稳态的一种自我调节机制。     

安宁包缺氧体系用于构建乳鼠心肌细胞缺氧/复氧损伤模型的研究

目的采用安宁包缺氧体系构建SD乳鼠原代心肌细胞缺氧/复氧损伤模型,评估其实验条件,为开展心肌缺血/再灌注损伤的分子机制研究奠定基础。方法采用安宁包缺氧体系分别处理SD乳鼠原代心肌细胞指定时间(3 h、4 h、6 h、12 h),再进行复氧24 h,并采用AnnexinV/PI双染-流式细胞术检测细胞凋亡率与坏死率。结果与正常组相比,安宁包缺氧体系处理6 h、12 h分别诱导心肌细胞坏死率上升29.82%和44.19%,差异具有统计学意义(P<0.01);与正常组相比,安宁包缺氧体系处理4 h后复氧24 h诱导心肌细胞凋亡率上升35.8%,差异具有统计学意义(P<0.01)。结论采用安宁包缺氧体系处理SD乳鼠原代心肌细胞4 h后复氧24 h为较合适的缺氧/复氧损伤模型实验条件。     

三碘甲状腺原氨酸对缺血再灌注损伤后未成熟心肌细胞中Bax、Bcl-2的影响

目的通过三碘甲状腺原氨酸对缺血再灌注损伤后未成熟心肌细胞中Bax、Bcl-2表达的影响,探讨其作用机制。方法培养原代乳鼠未成熟心肌细胞,通过缺氧复氧建立乳鼠心肌细胞缺血再灌注模型。于缺氧复氧前期给予三碘甲状腺原氨酸处理,通过聚合酶链反应仪检测三碘甲状腺原氨酸干预后心肌细胞的Bax mRNA和Bcl-2 mRNA表达情况。结果缺氧复氧前短期给予三碘甲状腺原氨酸可下调乳鼠未成熟心肌细胞Bax的表达,上调Bcl-2的表达,减少心肌细胞凋亡。结论三碘甲状腺原氨酸可以提高未成熟心肌抗缺血再灌注损伤的能力,而对心肌细胞凋亡这种保护作用与心肌细胞Bcl-2和Bax的表达相关。     

SOCS1介导CT-1对心肌细胞急性缺氧复氧损伤的保护作用

目的通过使用细胞因子信号抑制物1（SOCS1））反义寡核苷酸（ASODN）干预,从细胞和分子水平阐明SOCS1如何介导心肌营养素-1（CT-1）对心肌细胞缺氧复氧损伤的保护作用。方法用改良的方法培养出生1～3d的乳鼠心肌细胞,分为对照组：DMEM液培养6 h;缺氧复氧组;CT-1组：缺氧复氧＋CT-1;ASODN组1：缺氧复氧＋CT-1＋ASODN（终浓度为20μmol/L）;ASODN组2;SODN组：缺氧复氧＋CT-1＋SODN;ScODN组：缺氧复氧＋CT-1＋ScODN。测定心肌细胞的存活率、线粒体膜电位（Δψm）、细胞活性氧（ROS）、细胞凋亡率及SOCS1水平。结果缺氧复氧组较对照组心肌细胞凋亡率增加、ROS水平升高、心肌细胞存活率降低、Δψm下降,P均〈0.05;而CT-1组较缺氧复氧组心肌细胞存活率上升、凋亡率减少、Δψm增加。SOCS1 ASODN干预后,心肌细胞凋亡率和ROS水平明显升高,Δψm水平下降。缺氧复氧组SOCS1 mRNA和蛋白较对照组有所增加;CT-1组SOCS1 mRNA和蛋白均较缺氧复氧组升高,SOCS1 ASODN干预后下降。结论 SOCS1介导了CT-1减轻缺氧复氧引起的心肌细胞损伤。     

缺氧后处理对缺氧复氧心肌线粒体活性氧及细胞凋亡的影响

目的 观察缺氧后处理对缺氧复氧心肌线粒体活性氧及细胞膜和线粒体Bcl-2和Bax蛋白表达的影响,探讨其调控心肌细胞凋亡的机制.方法 构建大鼠乳鼠心肌细胞缺氧复氧损伤模型,将细胞分为对照组、缺氧/复氧纽(缺氧3h后复氧6h)、缺氧后处理组(缺氧3h后行复氧5min、缺氧5 min,反复3次,再复氧6 h).应用荧光酶标仪测定线粒体活性氧量,流式细胞仪检测心肌细胞凋亡,Western blot检测细胞膜和线粒体Bcl-2和Bax蛋白的表达.结果 缺氧/复氧组和缺氧后处理组心肌细胞线粒体活性氧量较对照组显著升高(P＜0.01).缺氧后处理组心肌细胞线粒体平均荧光强度为30.74±1.88a.u./μg,显著低于缺氧/复氧组(63.17±2.75a.u./μg,P＜0.01),仍高于对照组(14.41±2.15a.u./μg).缺氧/复氧组和缺氧后处理组心肌细胞凋亡率较对照组显著升高(45.86％±3.29％和26.99％±3.35％比5.72％±1.63％,P＜0.01),缺氧后处理组低于缺氧/复氧组(P＜0.01).细胞膜和线粒体Bcl-2蛋白在缺氧后处理组显著上调,在缺氧/复氧组显著下调;Bax蛋白在缺氧后处理组显著下调,在缺氧/复氧组显著上调.结论 缺氧后处理抑制线粒体活性氧爆发,减轻缺氧/复氧诱导的心肌细胞凋亡,其抗凋亡机制可能与线粒体和细胞膜Bcl-2蛋白表达上调及Bax蛋白表达下调有关.     

绿原酸对缺氧复氧心肌细胞内ankyrin-B的调节作用及其机制

目的:探讨绿原酸对缺氧复氧导致的心肌细胞内锚定蛋白-B(ankyrin-B)下降的调节作用及其机制。方法:培养乳鼠心肌细胞,分为对照组、缺氧复氧组和绿原酸处理组。以流式细胞法检测心肌细胞内活性氧(ROS)的水平,用Western-blot检测心肌细胞内ankyrin-B的表达。结果:缺氧复氧后心肌细胞内ROS水平明显增高,绿原酸预处理能够抑制ROS水平的增高[对照组:(237.6±22.3);缺氧复氧组:(612.1±25.6),绿原酸处理组:(375.9±30.1);P0.05]。缺氧复氧后心肌细胞内ankyrin-B的表达显著降低,绿原酸预处理能够上调ankyrin-B的表达。结论:绿原酸可能通过清除细胞内的ROS从而减少缺氧复氧引起的心肌细胞内ankyrin-B的表达降低。     

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.