急性肝衰竭大鼠脑水通道蛋白-4表达与脑水肿关系研究

急性肝功能衰竭（ALF）脑水肿常是导致死亡的直接原因和预后决定因素。ALF脑水肿是以星形胶质细胞肿胀为特征性的细胞性水肿。水通道蛋白-4（AQP-4）特异表达在星形胶质细胞膜，感受细胞内外渗透压的变化，调节水的跨细胞膜流动是细胞肿胀的分子基础。磁共振扩散加权成像（DWI）对细胞内、外水分子的扩散运动较敏感，能发现活体组织中水分布变化。通过建立大鼠ALF模型检测MR信号、血氨水平和AQP-4表达，探讨AQP-4在ALF脑水肿中的生化和分子机制。     

颅高压豚鼠脑组织中水通道蛋白-4表达水平的变化

目的探讨豚鼠弥漫性颅高压模型中脑内水通道蛋白（AQP）-4表达水平的动态变化．及其与脑组织水肿之间的相关性。方法应用脑池内注入脂多精（LPS）的方法建立豚鼠弥漫性颅高压模型（模碰组），并设正常对照组。Westem印迹法检测脑组织AQP-4 mRNA表达变化。结果对照组各时间点AQP-4 mRNA表达量之间无显著差异。模型组造模1h后AQP-4 mRNA表达开始增强，3h达高峰（P〈0．01），6h开始下降（P〈0．05）。对照组脑组织无明显异常。模型组动物脑组织严重水肿，神经元、神经胶质细胞和血管内皮细胞明显肿胀，血管周围间隙增加。结论脑池内注入LPS的方法建立豚鼠弥漫性颅高压模型早期可使AQP-4 mRNA表达增加，且与脑水肿程度有明显相关性。     

姜黄素对Aβ诱导的老年痴呆大鼠海马胶质纤维酸蛋白表达的影响

目的通过观察姜黄素对Aβ1～40诱导的阿尔茨海默病(AD)大鼠空间学习记忆能力及海马区星形胶质细胞胶质纤维酸蛋白(GFAP)表达的影响,探讨姜黄素的作用机制。方法选择健康SD大鼠48只,分为空白对照组、AD对照组、姜黄素给药组,每组16只。Aβ1～40诱导大鼠认知障碍模型,采用Morris水迷宫测定大鼠的学习记忆能力。采用免疫组织化学方法检测GFAP蛋白表达,RT-PCR检测GFAP mRNA表达。结果姜黄素干预后AD大鼠空间学习记忆能力明显改善(P<0.05);与空白对照组相比,AD对照组大鼠脑组织海马区可见星形胶质细胞GFAP表达明显增多(P<0.05),姜黄素给药组大鼠脑组织海马区GFAP mRNA及免疫阳性细胞表达较AD对照组下降(P<0.05)。结论姜黄素能够改善Aβ1～40诱导的AD模型大鼠空间学习记忆障碍,其机制可能与降低GFAP的表达和抑制星形胶质细胞活性有关。     

肝硬化肝性脑病大鼠脑水通道蛋白-4的表达与脑水肿的关系

目的:探讨肝硬化肝性脑病脑水肿的发生机制,为治疗脑水肿新方法的发现提供理论依据.方法:实验大鼠随机分为正常组(n=10)、正常氨负荷组(n=10)、肝硬化组(n=20)和肝硬化氨负荷组(n=20).后2组给予400 g/L CCl4橄榄油,按0.2 mL/kg腹腔注射.2次/wk,共12wk.前两组给与橄榄油.注射剂量、部位、频次、时间同后两组.正常氨负荷组、肝硬化氨负荷组分别在最后1次给药2d后,给与乙酸胺盲肠注射.4组大鼠通过尾静脉注射伊文恩蓝(EB)应用干式生化法测量动脉血氨,比色法测量EB含量,干-湿重法测量脑含水量,免疫组化法染色并通过图像分析系统分析脑组织中AQP4的表达.结果:肝硬化组动脉血氨与正常组、正常氨负荷组比较有差异性(97.20±29.66 μmol/Lvs 42.62±10.11,59.33±15.06 μmol/L,均P＜0.05),肝硬化氨负荷组的动脉血氨(420.18±75.91 μmol/L)与其他各组比较有明显的差异性(P＜0.01).肝硬化组EB和脑含水量与正常组、正常氨负荷组比较没有差异性.而肝硬化氨负荷组与其他各组比较有差异性(1.96±0.55 μg/g vs 1.41±0.46,1.19±0.38,1.05±0.18 μg/g;75.14±5.68 vs 65.58±4.14,62.14±2.29,66.27±4.57,均P＜0.05).肝硬化大鼠AQP4表达部位与正常大鼠一致,但肝硬化大鼠给与氨负荷后,无论是平均吸光度还是显色阳性面积均较正常组增高(P＜0.05).结论:AQP4可能在肝硬化肝性脑病大鼠脑水肿形成中起一定的作用.     

U0126及地塞米松对氨培养SD乳鼠脑星形胶质细胞AQP4表达的影响

目的观察氨培养的脑星形胶质细胞水通道蛋白4(AQP4)的表达,地塞米松及丝裂原活化蛋白激酶(MAPKs)信号转导通路抑制剂U0126对其表达的影响。方法分离、培养SD大鼠脑星形胶质细胞,分为氨培养组、氨培养+U0126组、氨培养+地塞米松组和正常对照组,采用免疫组织化学及逆转录聚合酶链式反应检测AQP4在蛋白和基因水平的表达和变化。结果氨可致培养的星形胶质细胞AQP4蛋白和AQP4 mRNA的表达增加。U0126和地塞米松均可使氨培养星形胶质细胞AQP4 mRNA和AQP4蛋白的表达减少。结论氨可致AQP4表达增加,U0126和地塞米松有细胞保护作用,可有效保护脑星形胶质细胞。     

高血压脑出血患者血肿周围组织超微结构变化与水通道蛋白-4mRNA表达的关系

目的 探讨高血压脑出血（HICH）患者血肿周围组织超微结构变化与水通道蛋白-4mRNA(AQP-4mRNA)表达的关系。方法 选择山东玲珑英诚医院2018年6月至2020年6月行开颅手术治疗的HICH患者68例，术中取血肿周围组织观察超微结构变化、脑水肿病理变化，采用半定量RT-PCR法检测脑水肿组织AQP-4mRNA表达。另取正常脑组织标本30例作为对照组，采用半定量RT-PCR法检测AQP-4mRNA表达。68例HICH患者分别根据出血至手术时间和血肿量分组，比较各组AQP-4mRNA表达。结果 脑组织超微结构变化：脑出血至手术时间5 h星形细胞胞体和周边足突肿胀对毛细血管造成压迫，粗面内质网扩张，内有大量水肿液，线粒体融合中的部分嵴和膜局部断裂；脑出血至手术时间36 h神经细胞部分变性，星形细胞明显肿胀，部分细胞变性、坏死；脑出血至手术时间86 h神经细胞变性，轴索内容物溶解，部分双层核膜融合或消失，管腔变窄甚至闭塞。脑组织病理变化：出血至手术时间5 h患者脑组织轻度水肿；出血至手术时间36 h患者脑组织中度水肿，可见部分肿胀细胞；出血至手术时间86 h脑组织重度水肿，细胞核消失...     

水通道蛋白-4与脑水肿

根据发生机制,脑水肿可分为细胞毒性水肿和血管源性水肿。前者是细胞膜正常渗透梯度被破坏导致水渗透性内流进入细胞,主要为细胞内水肿。血管周围星形胶质细胞足突的水通道蛋白-4(AQP4)可使水通过血脑屏障进入细胞,AQP4基因敲除可显著减少细胞毒性脑水肿模型的液体积聚。相反,血管源性水肿源于一种不依赖AQP的血脑屏障通透性增高机制,导致细胞外液体积聚。研究表明,AQP4有助于消除细胞外液体。基于AQP4与脑水肿形成和消除的关系,AQP和AQP表达调节剂可为脑水肿治疗药物的开发提供新的思路。     

褪黑素对Aβ诱导的大鼠脑组织GFAP和S100β蛋白表达的干预作用

目的观察褪黑素(MT)干预β淀粉样蛋白(Aβ)诱导的大鼠脑组织胶质纤维酸性蛋白(GFAP)和S100β蛋白的表达,探讨MT对老年痴呆症(AD)治疗的作用机制。方法 30只大鼠随机分为生理盐水对照组、β淀粉样蛋白(Aβ)诱导AD模型构建组(模型组)和AD模型+MT治疗组(MT组)。动物喂养40d时取大鼠脑组织,用HE染色观察脑组织病理变化,免疫组化染色法检测Aβ标记的脑组织部位以及Aβ对神经细胞毒性作用,同时检测胶质细胞的GFAP和S100-β蛋白的表达水平。结果 HE染色观察脑组织病变在MT组明显轻于模型组;免疫组化结果显示,Aβ的表达水平在模型组和MT组二者间无明显差异,但Aβ对海马CA3区神经元损伤作用在模型组要大于MT组。GFAP和S100β表达水平在模型组则显著高于MT组和正常组(P0.05)。结论用MT干预治疗,可降低AD模型鼠胶质细胞表达GFAP和S100β蛋白的水平,从而起到了减轻大脑神经元细胞的损伤作用。     

老龄与年轻大鼠脑出血后星形胶质细胞反应的比较

目的 观察年龄对脑出血后星形胶质细胞反应的影响.方法 年轻(3个月龄)和老龄(16个月龄)雄性SD大鼠脑内注入100 μl自体全血,观察与年龄相关的神经胶质细胞的反应.年轻、老龄模型组大鼠分别在脑内注血后6、12、24、72 h、7、14 d时间点处死动物(每组6只)进行GFAP免疫组化.假手术组作对照.观察GFAP染色的阳性细胞表达.结果 与年轻大鼠比较,老龄大鼠脑出血后3 d星形胶质细胞的反应较弱,GFAP阳性细胞数显著低于年轻大鼠,这种状况可持续到监测14 d(P<0.01).结论 老龄大鼠脑出血应答的星形胶质细胞反应较弱,老龄是影响脑出血后脑损伤的重要因素.     

雌激素对Aβ1-40诱导大鼠星形胶质细胞和NOS阳性细胞变化的影响

目的 探讨雌激素对淀粉样β蛋白诱导大鼠星形胶质细胞及NOS阳性细胞变化的影响.方法 于雄性SD大鼠双侧海马注射Aβ1～40,制作AD大鼠病理模型,颈部皮下植入E2,60 d后取脑行冻切片.采用组化和免疫组化方法,观察大鼠海马GFAP与NOS阳性细胞表达的变化,以及雌激素对上述指标的影响.结果 AD大鼠出现海马星形胶质细胞增生、肥大,数量明显多于正常对照组（P＜0.05）,并出现一氧化氮阳性星形胶质细胞;海马一氧化氮神经元数量较正常对照组显著减少（P＜0.05）.E2处理组星形胶质细胞增生不明显,数量明显少于AD模型组（P＜0.05）,且未见一氧化氮阳性星形胶质细胞;海马一氧化氮神经元数量较AD模型组显著增加（P＜0.05）.结论雌激素可减轻神经系统的损伤,对AD有一定防治作用,但其作用机制尚需进一步探讨.     

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.