迟发型脑血管痉挛致脑缺血后神经元自噬

目的探讨迟发型脑血管痉挛(DCVS)致脑缺血后神经元自噬的现象。方法建立自发性蛛网膜下腔出血(SAH)后DCVS兔模型,检测脑组织含水量以确定模型成功程度。在二次注血后的不同时间处死兔,取痉挛血管供血区域脑组织进行Western印迹、免疫组织化学等检测脑组织中神经元细胞坏死、凋亡和自噬现象。结果 SAH兔模型脑组织中存在神经元细胞坏死、凋亡和自噬现象。梗死后24 h脑组织含水量相比梗死前增多(P<0.05)。Western印迹及免疫组化证实DCVS和神经元细胞自噬存在关联。结论 DCVS致脑缺血组织中存在神经元自噬现象,脑血管痉挛的程度与神经元自噬存在一定的关联性。     

细胞内丝裂原活化蛋白激酶信号通路与脑缺血后神经元凋亡

脑缺血可导致梗死核心区细胞坏死和缺血半暗带细胞凋亡。脑缺血后,丝裂原活化蛋白激酶（mitogen－activated protein kinases, MAPKs）信号通路被激活,引起程序性细胞死亡,包括细胞凋亡。文章就M APKs信号家族与脑缺血后神经元凋亡的关系进行了综述。     

PI3K-AKT-mTOR信号通路在大鼠肺性脑病模型神经元自噬中的作用

目的探讨PI3K-AKT-m TOR信号通路在肺性脑病神经元自噬中的作用。方法对36只新生健康SD大鼠乳鼠建立离体培养大鼠皮层神经元,随机分为空白对照组、肺性脑病组、自噬抑制剂3-MA组后进一步建立了大鼠肺性脑病细胞模型,借助该模型运用CCK8法检测神经元活力、MDC染色观察神经元自噬泡数量、Western印迹法检测自噬相关蛋白LC3、Beclin-1及PI3K蛋白表达。结果与空白对照组比较,肺性脑病组神经元活力降低(P0.05);神经元自噬泡数量增多;LC3-Ⅱ/Ⅰ的比值、Beclin-1及磷酸化PI3K表达水平增加(P0.05)。使用自噬抑制剂3-MA预处理后,神经元活力降低更明显、自噬泡数量明显减少;缺氧诱导的自噬水平明显受到抑制,LC3-Ⅱ/Ⅰ的比值、Beclin-1及磷酸化PI3K表达水平明显降低。结论缺氧和二氧化碳潴留的信号使Beclin-1表达增加、LC3-Ⅰ向LC3-Ⅱ转化增加,加速PI3K磷酸化,使PI3K-AKT-m TOR信号通路失活,从而激活自噬信号通路,导致大脑神经元自噬增强。     

依达拉奉对蛛网膜下腔出血大鼠海马区神经元自噬及凋亡的影响

目的探讨依达拉奉对蛛网膜下腔出血(SAH)后大鼠海马区神经元自噬及凋亡的影响。方法 24只成年雄性SD大鼠随机分为假手术组、SAH模型组(SAH组)、3-甲基腺嘌呤组(3-MA组)和依达拉奉组(Edr组)。血管穿刺法制备SAH模型,3-MA组和Edr组在建模成功后经腹腔注射分别给予3-MA溶液、依达拉奉。HE染色检测海马区神经细胞病理变化;免疫组化法检测自噬相关因子Beclin-1、LC3-Ⅱ及Caspase-3的表达; TUNEL细胞凋亡检测凋亡相关因子Caspase-3的表达。结果与假手术组比较,SAH组海马区存活细胞数明显减少(P<0. 05),凋亡细胞数自噬相关因子Beclin-1、LC3-Ⅱ阳性细胞数明显增加(P<0. 05),Caspase-3蛋白阳性细胞数明显增加(P<0. 05);与SAH组比较,3-MA组海马区存活细胞数明显减少(P<0. 05),自噬相关因子Beclin-1、LC3-Ⅱ阳性细胞明显减少(P<0. 05),Caspase-3蛋白阳性细胞显著增加(P<0. 05); Edr组存活细胞数明显增加(P<0. 05),自噬相关因子Beclin-1、LC3-Ⅱ阳性细胞显著增加(P<0. 05),Caspase-3蛋白阳性细胞显著减少(P<0. 05)。结论依达拉奉增强SAH后神经元自噬,从而减少神经元凋亡,对神经元具有保护作用。     

银杏总黄酮通过ERK/NF-κB信号通路对兔蛛网膜下腔出血后血管痉挛的影响

目的 探究银杏总黄酮通过细胞外调节蛋白激(ERK)/核因子(NF)-κB信号通路对兔蛛网膜下腔出血(SAH)后血管痉挛的影响。方法 雄性家兔随机分为假手术组、模型组、银杏总黄酮(156 mg/kg)组、3,4,5,4′-四甲氧基二苯乙烯(DMU-212,ERK激活剂,18 mg/kg)组、银杏总黄酮(156 mg/kg)+DMU-212(18 mg/kg)组,每组6只,模型组和用药组兔建立SAH模型。分组处理后,检测各组神经功能并进行评分;尼氏染色检测各组大脑海马神经元形态变化;苏木素-伊红(HE)染色检测各组大脑基底动脉痉挛情况,比较各组管壁厚度及管腔横截面积;测定各组基底动脉血流速度和脑组织氧化应激因子[超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH)-Px、丙二醛(MDA)];Western印迹法检测各组脑组织ERK/NF-κB通路相关蛋白p-ERK/ERK、核内NF-κB p65蛋白表达水平。结论 与假手术组相比,模型组大脑海马神经元出现明显损伤,基底动脉表现出严重的痉挛现象,管壁厚度、神经功能评分、血流速度、MDA水平、p-ERK/ERK、核内NF-κB p65表达明显...     

亚麻醉浓度的七氟烷对局灶性脑缺血再灌注大鼠血脑屏障通透性的影响

目的 探讨亚麻醉浓度的七氟烷对局灶性脑缺血再灌注损伤(CIRI)大鼠血脑屏障(BBB)通透性的影响机制。方法 按照随机数字表法将40只SPF级SD雄性大鼠随机分为假手术组、模型组、实验组、对照组各10只。模型组、实验组、对照组采用线栓法制备大鼠局灶性CIRI模型，假手术组只进行穿线，不结扎；实验组每日给以1.2%七氟烷吸入治疗3 h,对照组每日给以1.08 mg/ml尼莫地平灌胃给药。2,3,5-三苯基氯化四氮唑(TTC)染色检测脑梗死面积，脱氧核糖核苷酸末端转移酶介导的缺口末端标记(TUNEL)染色检测脑组织的神经元凋亡率，伊文思蓝(EB)染色检测BBB通透性，Western印迹检测各组脑组织中闭合蛋白(Occludin)、紧密连接蛋白(Claudin)-5、闭锁连接蛋白(ZO)-1蛋白表达。结果 与假手术组相比，模型组、实验组、对照组脑组织的梗死面积、细胞的凋亡率、EB渗出量明显升高(均P<0.05),脑组织中Occludin、Claudin-5、ZO-1蛋白的表达明显下降(均P<0.05);与模型组相比，实验组、对照组脑组织的梗死面积、细胞的凋亡率、EB的渗出量明显下...     

Akt信号通路在非典型性抗精神病药物阿立哌唑调节海马神经细胞凋亡中的作用

目的探讨非典型性抗精神病药物阿立哌唑是否通过Akt信号通路对海马神经细胞的凋亡发挥作用。方法通过构建精神分裂症(CPZ)模型小鼠,设置对照组、阿立哌唑组、CPZ组、CPZ+阿立哌唑四组,实验结束后对小鼠断头取脑,冰上分离出海马组织和脊髓,培养海马神经细胞,流式细胞仪检测细胞凋亡情况,MTT检测细胞增殖、Western印迹检测自噬相关蛋白Beclin1的表达情况;使用磷酸化Akt信号通路试剂盒对总Akt,磷酸化Akt(Ser473)含量的变化情况进行检测。结果对饲养6 w后的小鼠提取海马神经细胞,流式细胞仪、MTT检测结果表明,建立CPZ模型的小鼠,在饲养过程中使用阿立哌唑能明显降低海马神经细胞的凋亡率;MTT检测结果表明,与对照组相比,使用阿立哌唑的CPZ模型小鼠海马神经细胞的存活率明显提高(P<0.01);Western印迹检测自噬相关蛋白Beclin1的结果表明,构建的CPZ模型小鼠脊髓受到一定程度损伤,Beclin1的表达量明显升高(P<0.01),给阿立哌唑后其表达量显著下降;在CPZ组中总Akt及Ser473的表达水平均显著下降(P<0.01),通过服用阿立哌唑后表达水平出现回升,与对照组相比差异不显著(P>0.05)。结论非典型性抗精神病药物阿立哌唑可通过Akt信号通路使海马神经细胞免于凋亡。     

缺血预处理对大鼠缺血脑组织p-p38MAPK、Fas、FasL蛋白表达的影响

目的研究p-p38MAPK、Fas、FasL蛋白在大鼠脑缺血再灌注脑梗死组织中表达的变化。方法取SPF级SD健康雄性大鼠随机分为模型组、缺血预处理组和假手术组;按照观察时间点各组又分为6 h、12 h、24 h、48 h、72 h亚组。缺血预处理组大鼠,预先给予右侧颈内动脉阻断血流10 min 1次。3 d后,采用大脑中动脉线栓法,建立局灶性脑缺血再灌注损伤模型;模型组用大脑中动脉线栓法建立脑缺血再灌注模型;假手术组大鼠仅需分离右侧颈总动脉。在术后各个观察时间点评估各组大鼠的神经功能缺损评分,TTC法检测脑梗死体积,免疫组化法测定梗死脑组织p-p38MAPK、Fas、FasL蛋白水平的表达,TUNEL法检测神经元的凋亡。结果假手术组大鼠无神经功能缺损及脑梗死;缺血预处理组大鼠神经功能行为评分及脑梗死体积显著小于模型组(P0.05);同一时间点的各组间比较:p-p38MAPK、Fas、FasL的表达及神经元凋亡细胞数,模型组显著高于预处理组且两者均显著高于假手术组(P0.05)。结论脑缺血再灌注损伤可以促进p38MAPK的磷酸化,上调Fas、FasL蛋白水平的表达,激活它们所在的信号通路引起神经元的凋亡。脑缺血预处理可抑制p38MAPK的磷酸化,下调p-p38MAPK、Fas、FasL蛋白的表达水平,抑制神经元的凋亡;抑制p38MAPK的磷酸化及Fas、FasL凋亡通路的激活可能是脑缺血预处理产生脑缺血耐受的机制之一。     

cGAS抑制剂对小鼠脑缺血再灌注损伤的干预作用及其机制

目的 观察cGAS抑制剂对小鼠脑缺血再灌注损伤的干预作用，并基于自噬调节探讨相关机制。方法 雄性C57BL/6小鼠18只，随机分为假手术组、模型组、实验组，每组6只。模型组、实验组采用线栓法制备大脑中动脉栓塞模型，实验组在再灌注前10 min腹腔注射5 mg/kg的cGAS抑制剂RU. 521，假手术组分离大脑中动脉但不阻断。再灌注6 h后行HE染色、Nissl染色观察脑组织病理变化，Western blotting法检测脑组织中的cGAS、LC3B、Beclin-1蛋白，免疫荧光法检测凋亡细胞并计算凋亡率。结果 与假手术组相比，模型组神经元数量减少，细胞固缩，实验组上述改变减轻。模型组脑组织中cGAS、LC3B、Beclin-1蛋白相对表达量及细胞凋亡率高于假手术组，实验组cGAS、LC3B、Beclin-1蛋白表达及细胞凋亡率低于模型组（P均<0.05）。结论 cGAS抑制剂预处理可减轻小鼠脑缺血再灌注损伤，其机制可能与调节自噬相关蛋白表达有关。     

自噬抑制剂3-MA对乳胞素抑制胃癌BGC-823细胞增殖的影响及其机制

目的探讨联合应用自噬抑制剂3-Methyladenine(3-MA)和蛋白酶体抑制剂乳胞素(Lactacystin,LAC)对胃癌细胞系BGC-823增殖的影响及其机制。方法体外培养BGC-823细胞,MTT法检测BGC-823细胞增殖率,Western印迹检测线粒体凋亡相关蛋白Cytochrome C以及内质网凋亡相关蛋白caspase-4表达水平。结果与对照组相比,蛋白酶体抑制剂LAC可以引起明显的BGC细胞增殖率的下降,联合应用3-MA可以增加其引起的细胞增殖率的下降,Western印迹结果显示LAC可以上调线粒体凋亡相关蛋白Cytochrome C以及内质网凋亡相关蛋白caspase-4表达水平,联合应用3-MA和LAC可以进一步引起表达水平的升高。结论自噬抑制剂3-MA可以增加LAC引起的细胞凋亡,通过线粒体和内质网凋亡信号通路。     

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.