辛伐他汀预处理对大鼠局灶性脑缺血再灌注时间窗的影响

目的研究辛伐他汀预处理对大鼠局灶性脑缺血不同灌注时间窗的脑保护作用;探讨药物干预再灌注时间窗的可行性。方法线栓法制作大鼠缺血再灌注损伤模型,实验随机分为假手术组（A组）、缺血组（B组）、缺血/再灌注组（C组）、缺血/再灌注组加辛伐他汀组（D组）。C组、D组又各分为MCAO术后2h、4h、6h再灌注组。在完成预定操作后进行神经功能评分优于B组,测梗死体积,脑组织病理变化情况。结果D组各时间点神经功能评分优于B组,梗死体积小于B组（P〈0.05或P〈0.01）,脑组织病理变化改善。结论辛伐他汀预处理可改善神经功能评分,缩小梗死体积,改善脑组织病理变化,延长再灌注时间窗。     

环磷酸腺苷-蛋白酶A信号系统参与神经生长因子促进脑缺血再灌注大鼠轴突再生

目的观察脑室注射神经生长因子(NGF)对脑缺血再灌注大鼠神经再生的影响及其与环磷酸腺苷-蛋白激酶A(cAMP-PKA)信号途径的关系。方法采用线栓法制作大鼠脑缺血再灌注模型,将60只大鼠分为假手术组(对照组),单纯脑缺血再灌注组(缺血组),NGF1组,NGF2组(脑缺血再灌注并脑室注射NGF,分别注入0.5及2.5μg/100 g体重)。用放免法检测缺血周边区脑组织cAMP的含量,逆转录聚合酶链反应的方法检测生长相关蛋白43(GAP-43)及蛋白激酶A(PKA)mRNA的表达。结果缺血组6、24 h cAMP的含量下降,GAP-43及PKA mRNA表达减少,NGF治疗组脑组织GAP-43 mRNA表达较缺血组增加,且这种变化与cAMP的含量及PKA mRNA表达增加相一致,并呈剂量依赖性。结论NGF能够促进脑缺血再灌注后的轴突再生,cAMP-PKA信号途径在这个过程中起重要作用。     

依达拉奉对局灶性脑缺血再灌注大鼠大脑皮层细胞凋亡及相关蛋白表达的影响

目的探讨依达拉奉对局灶性脑缺血再灌注大鼠大脑皮层细胞凋亡及相关蛋白表达的影响。方法 Wistar大鼠随机分为:假手术组、缺血再灌注模型组(模型组)、依达拉奉治疗组(依达拉奉组)。采用线栓法制作大鼠局灶性脑缺血再灌注模型,观察不同组大鼠的神经功能症状评分。分别于缺血后2 h进行再灌注。依达拉奉组于缺血再灌注后1 h及1.5 h在腹腔内注射依达拉奉注射液(按照3 mg/kg)2次,在缺血再灌注后6、12、48 h处死大鼠。TUNEL法原位检测凋亡细胞,免疫组化法检测脑组织Caspase-3表达的阳性细胞数。结果模型组在再灌注48 h梗死体积最大,12 h凋亡细胞数最多。缺血再灌注后6 h在大脑额叶和海马即可见到Caspase-3蛋白表达的阳性细胞,12 h组最高。依达拉奉组各时间点脑梗死体积、Caspase-3表达水平较模型组明显降低(P<0.01)。结论依达拉奉对缺血再灌注大鼠皮层脑细胞具有保护作用,其机制可能与抑制Caspase-3表达,从而抑制皮层细胞凋亡有关。     

电针对脑缺血再灌注后大鼠脑缺血区生长相关蛋白-43与神经蛋白聚糖表达的影响

目的 探讨电针治疗对脑缺血再灌注后大鼠脑缺血区不同时间点生长相关蛋白(GAP)-43及神经蛋白聚糖(Neurocan)表达的影响.方法 将60只健康成年SD雄性大鼠随机分为假手术组(n=10)、大脑中动脉闭塞再灌注(MCAOR)组(n=25)和治疗组(n=25).用线栓法建立右侧MCAOR模型,治疗组选取人中、百会穴给予电针刺激.选取1、3、7、14、21 d五个时间点,应用免疫组化、RT-PCR方法检测缺血区皮层GAP-43及Neurocan阳性细胞及其mRNA的表达情况.结果 GAP-43及Neurocan在假手术组不表达,MCAOR后表达增加,且电针治疗组较MCAOR组表达差异显著(P<0.01).缺血2 h再灌注1 d MCAOR组出现GAP-43及Neurocan阳性表达细胞,并且呈先递增后减少的趋势.再灌注后7 d时,MCAOR组的GAP-43阳性细胞及其mRNA表达达到高峰,14 d时降至接近初始水平,但治疗组GAP-43表达仍维持较高水平.MCAOR组的Neurocan阳性细胞及其mRNA 7 d明显增多,14 d达高峰,21 d时下降,但仍高于假手术组水平(P<0.01);治疗组 Neurocan表达在缺血再灌注3、7、14、21 d较对照组显著减少(P<0.01).结论 电针上调脑缺血区GAP-43表达与下调Neurocan表达,可能是其促进脑损伤区中枢神经修复的重要机制之一.     

桂哌齐特对大鼠局灶性脑缺血后脑腺苷含量和肿瘤坏死因子-α表达的影响

目的　探讨大鼠局灶性缺血后脑腺苷含量、肿瘤坏死因子 α的变化及对桂哌齐特的影响。方法　雄性SD大鼠 79只 ,随机分为假手术组、模型组和桂哌齐特组用高效液相色谱法、免疫组织化学法分别检测脑腺苷含量及肿瘤坏死因子 α的表达。结果　缺血后 2 0min脑腺苷含量急骤升高 ,缺血后 1h及再灌注后回落 ;桂哌齐特组较模型组显著升高。脑再灌注后肿瘤坏死因子 α的表达明显升高 ,桂哌齐特组明显低于模型组 ,且脑组织损伤减轻。结论　桂哌齐特有保护大鼠局灶性脑缺血再灌注损伤的作用。可能与其增加内源性腺苷含量从而加强腺苷抑制炎症反应的脑保护效应有关     

光化学法诱导颞叶皮层梗死大鼠生长相关蛋白43的表达及巴曲酶的作用

目的 研究光化学法诱导的颞叶皮层梗死大鼠生长相关蛋白43(GAP-43)的表达及巴曲酶的作用。方法 用免疫组化染色法和苏木素伊红染色法研究GAP-43的表达和病理变化的关系。结果 脑梗死后1d,梗死区GAP-43的表达明显增多,梗死灶处额叶新皮层神经元分层排列消失,神经元数量明显减少,神经毡被破坏,组织严重水肿;巴曲酶使梗死区GAP-43的表达进一步增多,并可减轻梗死灶神经毡的破坏和组织水肿。结论 光化学法可诱导大鼠颞叶皮层出现梗死,且梗死区GAP-43的表达增多;巴曲酶可促进梗死区GAP-43的表达,并改善其病理变化。     

肌苷对大鼠脑缺血再灌注后生长相关蛋白基因表达和神经功能恢复的影响

目的:探讨肌苷对脑缺血再灌注后中枢神经再生的作用。方法:应用线栓法建立大脑中动脉闭塞(MCAO)缺血再灌注模型,腹腔注射肌苷治疗,采用Bederson等神经功能评分法评定神经功能的恢复,原位杂交技术检测脑缺血再灌注后2h、12h、1d、2d、3d、7d、14d脑组织GAP-43 mRNA的表达。结果:对照组缺血侧GAP-43 mRNA表达皮质区除1 d和14 d外、纹状体区除2 h和14 d外各时间点均明显高于假手术组(P<0.05)。肌苷治疗组较对照组GAP-43 mRNA表达在皮质区于再灌注2 h-过性下降,12 h升高;在纹状体区12 h升高,7 d再次升高;神经功能恢复于再灌注7-14 d有显著改善(P<0.05)。结论:肌苷可促进大鼠脑缺血再灌注后神经功能恢复,其作用机制可能是通过调节与神经轴突再生有关的GAP-43 mRNA表达而实现的。     

瑞芬太尼对小鼠脑缺血再灌注损伤的神经保护作用

目的观察瑞芬太尼对小鼠脑缺血再灌注损伤后神经功能障碍及梗死灶体积的影响。方法线栓法制备大脑中动脉阻塞的脑缺血再灌注模型。96只雄性小鼠随机分为假手术组、模型组和瑞芬太尼预处理组。再灌注24 h后进行神经功能缺陷评分,氧化三苯甲基四氮唑(TTC)染色测定梗死面积,酶联免疫吸附法(ELISA)检测缺血侧大脑皮层组织中白细胞介素(IL)-1β、肿瘤坏死因子(TNF)-α、IL-10和转化生长因子(TGF)-β1的含量,并用蛋白免疫印迹法检测缺血侧大脑皮层组织中核转录因子κB(NF-κB)的活性。结果瑞芬太尼能明显改善小鼠的神经行为,缩小梗死面积,抑制促炎症因子IL-1β和TNF-α的表达,而增加抗炎症因子IL-10和TGF-β1的表达,并抑制NF-κB的活化。结论瑞芬太尼对小鼠脑缺血再灌注损伤具有明显的保护作用,其机制与抵抗炎症反应有关。     

SIRT1信号通路在白藜芦醇保护脑缺血再灌注损伤中的作用机制

目的探讨白藜芦醇(Res)对大脑缺血再灌注损伤后大鼠神经元凋亡的影响及其作用机制。方法采用线栓法制作短暂性大脑中动脉栓塞(MCAO)模型。将60只SD大鼠随机分为假手术组(Sham组)、脑缺血再灌注模型组(MCAO组)、白藜芦醇低剂量(10 mg/kg)组(Res 10组)、白藜芦醇高剂量(30 mg/kg)组(Res 30组)。栓塞缺血2 h、再灌注24 h后对各组大鼠进行神经功能损伤评分、脑组织含水量及脑梗死体积评估,TUNEL染色检测细胞凋亡,同时测定缺血再灌注损伤缺血测脑组织中SIRT1、Bax、Caspase-3 mRNA表达水平。结果脑缺血再灌注后24 h,MCAO组脑梗死体积大于Sham组(P0.01),神经功能损伤评分、脑组织含水量、TUNEL(+)细胞数及Bax mRNA、Caspase-3 mRNA表达量均明显高于Sham组(P0.01),而SIRT1 mRNA表达量较Sham组明显降低(P0.01)。与MCAO组比较,Res 10组、Res 30组脑梗死体积明显缩小(P0.01),神经功能损伤评分、脑组织含水量、TUNEL(+)细胞数以及脑组织中Bax mRNA、Caspase-3 mRNA表达量明显降低(P0.01),SIRT1 mRNA表达明显增加(P0.01)。结论白藜芦醇可通过减轻缺血脑组织神经元凋亡对大鼠脑缺血再灌注损伤发挥神经保护作用,其可能通过激活SIRT1信号通路从而抑制或逆转脑缺血再灌注神经损伤的发生。     

AMP-活化蛋白激酶对局灶性脑缺血再灌注小鼠皮质胱天蛋白酶-8、-3表达和细胞凋亡的影响

目的 探讨抑制AMP-活化蛋白激酶(AMP-activated protein kinase,AMPK)活性对局灶性脑缺血再灌注小鼠梗死体积、缺血皮质胱天蛋白酶-8、-3表达以及细胞凋亡的影响.方法 72只雄性C57BL/6小鼠,随机数字表法分为假手术组、缺血再灌注组和AMPK抑制剂组.线栓法建立大脑中动脉闭塞(middle cerebral artery occlusion,MCAO)模型.AMPK抑制剂组在MCAO即刻腹腔注射Compound C(20 mg/kg),假手术组及缺血再灌注组在相同时间点腹腔注射等量生理盐水.应用2,3,5-三苯基氯化四氮唑(2,3,5-triphenyltetrazolium chloride,TTC)染色法测量脑梗死体积,免疫组化染色法检测胱天蛋白酶-8、-3表达水平,TUNEL染色法检测细胞凋亡.结果 假手术组未见梗死灶,无胱天蛋白酶-8、-3以及凋亡阳性细胞.与缺血再灌注组比较,AMPK抑制剂组梗死体积显著缩小[(45.34±7.20)mm3对(22.71±4.93)mm3;t=5.730,P=0.037],大脑皮质胱天蛋白酶-8[(17.58±8.62)个/HP对(6.87±4.32)个/HP;t=3.631,P=0.023]、胱天蛋白酶-3[(16.21±5.46)个/HP对(8.22±4.64)个/HP;t=2.630,P=0.021]和凋亡[(78.44±8.32)个/HP对(55.73±6.71)个/HP;=5.541,P=0.042]阳性细胞数量均显著减少.结论 抑制AMPK活性可缩小局灶性脑缺血再灌注小鼠梗死体积,其机制可能与下调胱天蛋白酶-8、-3表达和减少细胞凋亡有关.     

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.     

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.