黄芪对缺氧心肌细胞保护作用的研究

目的 :探讨黄芪对心肌细胞的保护作用及其可能的机制。方法 :将原代培养的乳鼠心肌细胞随机分为 5组 :正常对照组 (N组 )、缺氧对照组 (H组 )、缺氧加黄芪组 1(A1组 )、缺氧加黄芪组 2 (A2 组 )、缺氧加黄芪组 3(A3 组 )。A1、A2 、A3 组于缺氧前加入黄芪 ,黄芪的终浓度分别为 10g/L、10 0 g/L、10 0 0 g/L。缺氧 30min ,流式细胞仪测定各组心肌细胞凋亡率 ,RT PCR检测肿瘤坏死因子α(TNF α)mRNA的表达水平。结果 :H、A1、A2 、A3与N组相比 ,缺氧 30min ,细胞凋亡率显著升高 (P <0 .0 1) ,并有TNF αmRNA表达 ;A2 、A3 组与H相比较 ,细胞凋亡率分别降低 34.96 %、37.0 2 % (P <0 .0 5 ) ,同时TNF αmRNA的生成减少 (P <0 .0 5 ) ,但以上指标均未恢复正常 (P <0 .0 1～ 0 .0 5 )。结论 :一定浓度的黄芪可能减少缺氧心肌细胞凋亡及损伤 ,并抑制TNF α表达 ,但该作用并非与浓度正相关     

缺氧对心肌细胞内游离钙离子浓度和SERCA2表达的影响及薯蓣皂甙的干预作用

目的　研究缺氧对心肌细胞内游离钙离子浓度和肌浆网上的钙离子ATP酶(SERCA2 )的表达的影响及薯蓣皂甙的干预作用。方法　在离体心肌细胞培养基础上制备心肌细胞缺氧模型 ,随机分为 4组 :正常对照组 ,缺氧损伤组 ,薯蓣皂甙组 ,钙拮抗剂组。分别测定各组心肌细胞内游离钙离子的浓度 (FURA2 /AM荧光探针法 )和SERCA2的含量 (Westernblot法 )。结果　缺氧损伤组心肌细胞内游离钙离子的浓度较正常对照组明显增加 ,SERCA2的表达明显减弱 (P均 <0 0 1 ) ;薯蓣皂甙组和钙拮抗剂组心肌细胞内游离钙离子的浓度较缺氧损伤组明显降低 (P <0 0 1 ) ,SERCA2的表达明显增强 (P <0 0 5 )。结论　薯蓣皂甙通过增强肌浆网上钙泵SERCA2的表达减轻缺氧心肌细胞的钙超负荷 ,它对缺氧心肌细胞具有保护作用 ,其作用与钙拮抗剂类似。     

苯那普利对缺氧复氧心肌心胞内钙离子的影响及机制研究

目的研究苯那普利对乳鼠缺氧复氧心肌细胞内钙离子浓度的影响及作用机制。方法采用纯化培养的乳鼠心肌细胞复制缺血再灌注模型。实验分为4组,每组8例：空白对照组、单纯缺氧复氧组（H／R）、缺氧复氧＋苯那普利（1×10^6mol／L）组、缺氧复氧＋苯那普利（1×10^6mol／L）＋缓激肽B2受体拮抗剂（HOE140）（1×10^6mol／L）组。细胞缺氧1h,复氧2h后取细胞培养液测定乳酸脱氢酶（LDH）,取细胞测定超氧化物歧化酶（SOD）的活性和丙二醛（MDA）含量,测定细胞内钙浓度。结果单纯缺氧复氧组与对照组比较,LDH、MDA、[Ca^2＋]i含量升高,SOD活性下降（P〈0．01）;苯那普利组与缺氧复氧组比较,LDH、MDA、[Ca^2＋]i含量降低,SOD活性升高（P〈0．01）;苯那普利＋HOE140组与苯那普利组比较,LDH、MDA、[Ca^2＋]i含量升高,SOD活性下降（P〈0．01）。结论苯那普利能降低细胞内钙离子浓度,有明显保护心肌的作用。其作用可能与激活激肽-缓激肽释放系统、抑制缓激肽的降解有关。     

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。     

冬虫夏草水提液抗脂质过氧化损伤的实验研究

在细胞水平研究冬虫夏草水提液对心肌细胞缺氧再给氧时细胞内丙二醛(MDA)含量、超氧化物歧化酶(SOD)活性及细胞膜脂质流动性的影响,探讨冬虫夏草抗脂质过氧化作用及其可能机制。结果显示缺氧再给氧组心肌细胞MDA含量增加,SOD活性降低,细胞膜脂质流动性下降,与对照组比较,P均<0.01;缺氧再给氧 冬虫夏草组上述改变减轻,其中100μg·ml~(-1)、1000μg·ml~(-1)组上述指标与缺氧再给氧组及10μg·ml~(-1)组比较,P均<0.01。实验表明缺氧再给氧时细胞内脂质过氧化作用增强;冬虫夏草明显减轻缺氧再给氧时细胞内脂质过氧化作用,且呈良好量效关系。     

羟基红花黄色素A对缺氧心肌细胞的保护作用

目的观察羟基红花黄色素A(HSYA)对缺氧心肌细胞的保护作用。方法体外培养大鼠乳鼠心肌细胞,随机分为正常对照、缺氧损伤、HSYA1×10-6mol/L～1×10-10mol/L组、地尔硫艹卓组,同时设1×10-6mol/LHSYA正常对照组。以高纯氮气封罐,无糖无血清培养液密闭培养制备心肌细胞缺氧模型,观察各组细胞形态学变化,计数细胞搏动频率,测定心肌细胞存活率、细胞培养液中乳酸脱氢酶(LDH)活性、细胞内的丙二醛(MDA)浓度及ATP酶活性。结果与缺氧损伤组比较,1×10-7mol/L和1×10-8mol/L浓度HSYA组心肌细胞仍存在规律性搏动,细胞存活率显著升高,细胞培养液中LDH活性、心肌细胞内MDA的含量明显低于缺氧损伤组(P<0.05,P<0.01),而细胞内ATP酶的活性较缺氧损伤组显著增高(P<0.01)。结论1×10-7、1×10-8mol/L浓度的HSYA可有效的保护心肌细胞免受缺氧损伤。     

神经肽Y、蝙蝠葛酚性碱对兔心肌缺血再灌注损伤内皮功能的影响

目的 :研究神经肽 Y(Neuropeptide Y ,N PY)对心肌缺血再灌注 (m yocardial ischemia reperfusion,MIR)损伤的影响及蝙蝠葛酚性碱 (phenolic alkaloids of m enispermun dauricum ,PA MD)的保护作用。方法 :将实验兔 32只随机分为 4组 :1假手术组 ;2 MIR组 ;3MIR加 NPY组 ;4MIR加 NPY加 PAMD组。观察缺血前 ,缺血 30 min,再灌 10、30 min,1、2、3、4h血液一氧化氮 (NO)、超氧化物歧化酶 (SOD)、丙二醛 (MDA)的含量变化 ,缺血后 10 min给予 N PY静注对上述指标的影响以及缺血前静脉注射钙离子抑制剂 PAMD,NPY对上述指标影响的逆转作用。结果 :1MIR组与假手术组比较 ,NO下降 ,SOD下降 ,MDA上升。2 MIR加 NPY组与 MIR组比较 ,N O、SOD活性均明显下降 (P <0 .0 5 ,<0 .0 1) ,MDA含量明显上升 (P <0 .0 1) ;3NPY对 NO、SOD、MDA的影响可被 PAMD逆转。结论 :NPY通过加重对内皮功能的损伤作用而加重心肌缺血再灌注损伤 ,可能的机制是增加细胞内钙的负荷 ,钙离子通道抑制剂对 NPY的此种效应有逆转作用 ,支持 NPY通过增加细胞内钙负荷 ,使自由基清除能力下降的途径损伤心肌细胞 MIR时的内皮功能     

黄芪苷Ⅳ对心肌细胞氧化损伤的保护作用

目的研究黄芪苷Ⅳ对阿霉素所致心肌细胞损伤的保护作用。方法以原代培养乳鼠心肌细胞建立损伤模型。实验分3组。正常对照组;模型组:阿霉素分别为0.5、1.0mg/L与乳鼠心肌细胞共同培养;黄芪苷Ⅳ组:在加入阿霉素前1h分别给予黄芪苷Ⅳ10、20mg/L,然后加入与模型组相同浓度的阿霉素共同培养。观察心肌细胞四甲基偶氮唑盐(MTT)代谢率、丙二醛(MDA)含量及一氧化氮合酶(NOS)活性的变化,并测定心肌细胞内的游离钙离子浓度。结果阿霉素组心肌细胞的MTT代谢率显著降低(P<0.01),MDA含量增加(P<0.05),NOS活性升高(P<0.05),[Ca2+]i升高(P<0.01)。黄芪苷Ⅳ可使阿霉素损伤的心肌细胞MTT代谢率提高,MDA含量减少(P<0.05),NOS活性降低(P<0.05),[Ca2+]i降低(P<0.01)。结论黄芪苷Ⅳ对受损伤的心肌细胞具有明显的保护作用。     

硫酸镁对低氧性肺动脉高压大鼠血中丙二醛和超氧化物歧化酶的影响

目的 :探讨硫酸镁对低氧性肺动脉高压大鼠血中丙二醛 (MDA)和超氧化物歧化酶(SOD)的影响。方法 :将 2 4只Wistar大鼠随机分为缺氧组、硫酸镁组和对照组。 4周后测血浆MDA含量和红细胞SOD活性。结果 :硫酸镁组较缺氧组血中MDA含量显著降低 (P <0 .0 5 ) ,而SOD活性显著升高 (P <0 .0 1)。结论 :低氧时脂质过氧化反应增强 ,硫酸镁能抑制脂质过氧化和降低肺动脉压。     

左旋氨氯地平对缺氧心肌细胞乳酸脱氢酶和肌钙蛋白的影响

目的　探讨钙离子拮抗剂左旋氨氯地平对缺氧心肌细胞损伤标记物及细胞内游离钙离子浓度的影响。方法　在离体乳鼠心肌细胞培养基础上制备心肌细胞缺氧模型 ,随机分为正常对照组、缺氧损伤组和钙拮抗剂干预缺氧损伤组。分别测定各组心肌培养基中乳酸脱氢酶、肌钙蛋白的含量 ,心肌细胞内游离钙离子的浓度 (荧光探针法 )。结果　缺氧损伤组心肌培养基中乳酸脱氢酶和肌钙蛋白的含量及心肌细胞内游离钙离子浓度较正常对照组明显增加 (P均 <0 .0 1) ;经左旋氨氯地平干预后细胞培养基中乳酸脱氢酶和肌钙蛋白的含量及心肌细胞内游离钙离子浓度较缺氧损伤组明显降低 (P均 <0 .0 1)。结论　左旋氨氯地平对缺氧心肌细胞具有保护作用 ,其机理可能与减轻心肌细胞内钙超负荷有关     

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.     

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.     

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.