脑缺血再灌注大鼠皮质和纹状体的脑源性神经营养因子的mRNA表达

目的观察大鼠大脑中动脉阻塞(MCAO)后脑缺血再灌注不同时程大鼠皮质和纹状体区脑源性神经营养因子(BDNF)基因表达的变化。方法应用线栓法建立缺血1h再灌流2、6、12、24h及2、3、7、14d等8个时间点模型。原位杂交方法观察不同脑区BDNFmRNA阳性细胞表达及其时程变化规律。结果脑缺血1h再灌注2、6、12、24h及2、3d后,与假手术组比较皮质区BDNFmRNA表达阳性细胞数显著增加(P<001),并且阳性细胞数在2h和24h出现两个高峰值,显著高于另外时间段(P<005),呈现双驼峰升高现象,再灌注7d和14d时BDNFmRNA表达降至基础水平。纹状体缺血1h再灌注后所有时间段BDNFmRNA表达阳性细胞数均明显高于假手术组(P<005,P<001),并且阳性细胞数在2h和3d出现两个高峰值,显著高于另外时间段(P<005),呈双驼峰升高现象。再灌注2、6、12、24h和2、3、7d平均单个视野BDNFmRNA阳性细胞数,皮质区显著高于纹状体区(P<005)。结论MCAO大鼠皮质和纹状体BDNFmRNA阳性细胞数表达增高,并且出现双驼峰升高现象,应急保护可能与BDNFmRNA表达第一高峰有关,神经细胞自我修复可能与第二高峰有关。     

阿托伐他汀预处理和缺血预处理对大鼠脑缺血再灌注损伤的保护作用

目的观察阿托伐他汀预处理和缺血预处理对脑缺血再灌注损伤后的形态学改变,探寻更为有效的脑保护药物及防治方法。方法选择Wistar大鼠32只,随机分为4组。假手术组,缺血再灌注组,缺血预处理组,阿托伐他汀组,每组8只。采用线栓法建立大脑中动脉可逆性局灶性脑缺血再灌注模型,实验结束后取脑固定。经视交叉平面冠状切取脑组织厚2mm,包含新皮质(主要是额顶叶)、视前区及梨状区、纹状体、海马和丘脑。切成3μm的切片,行HE染色观察额顶叶皮质区及海马CAl区形态学变化。结果缺血再灌注组大脑额顶叶皮质区和海马CAl区核固缩性改变、细胞质嗜酸性改变较假手术组、缺血预处理组和阿托伐他汀组明显加重,差异有统计学意义(P<0.01)。结论脑缺血预处理和阿托伐他汀预处理对大鼠脑缺血再灌注损伤均有保护作用。     

局灶性缺血再灌注大鼠脑线粒体损伤的实验研究

采用大鼠大脑中动脉缺血（MCAO）再灌注模型，观察缺血再灌注不同时相（分为五组）脑线粒体损伤的变化规律。结果为脑缺血再灌注后线粒体基质游离钙含量（MCa）明显高于假手术组Na^＋、K^＋-ATP酶、Ca^2＋、Mg^＋-ATP酶活性明显下降，且随时间的延长下降明显；再灌注0．5h的MDA和SOD均元明显变化，再灌注1h后线粒体MDA含量明显升高，SOD活性明显下降。说明脑缺血再灌注线粒体损伤与线粒体钙超载及线粒体内膜氧化磷酸化有关。     

大鼠局灶性脑缺血再灌注后Nogo-A表达和神经元凋亡

目的：探讨大鼠脑缺血再灌注后轴突生长抑制因子Nogo-A表达和神经细胞凋亡。方法：36只成年健康雄性Wistar大鼠随机分为假手术组和缺血1h再灌注2h、6h、12h、1d,2d、3d、7d、14d组,每组4只。应用线栓法制备大鼠脑缺血再灌注模型,分别用TUNEL法和免疫组织化学法观察神经细胞凋亡和Nogo-A表达。结果：假手术组海马、皮质和纹状体区可见少量凋亡神经细胞。再灌注2h凋亡细胞逐渐增多,3～7h达高峰,随后下降。Nogo-A表达于再灌注2h开始明显增加,并一直保持在较高水平。结论：脑缺血再灌注后Nogo-A表达增高,细胞凋亡也增加。     

托吡酯对脑缺血再灌注后脑保护作用的研究

目的 探讨托吡酯对大鼠高血压急性脑缺血再灌注后的脑保护作用。 方法 将25只大鼠制成高血压模型,喂养2个月。随机分为3组:即托吡酯治疗组(9只)、缺血再灌注组(9只)和假手术组(7只)。将大鼠用线栓法制成大脑中动脉闭塞模型,缺血时间为2 h,将线栓拔除即形成缺血-再灌注模型。假手术组末置入线栓。再灌注后6 h,将大鼠快速断头取脑,经TTC染色,用计算机病理图像分析仪测量鼠脑梗死体积及鼠脑总体积,并将两者的比值作为脑梗死体积比。结果 托吡酯治疗组的脑梗死体积比为0.1087±0.0426,明显小于缺血-再灌注组脑梗死体积比0.286 3±0.064 7(P<0.05)。假手术组未见梗死灶。结论 托吡酯使大鼠高血压脑缺血-再灌注后的脑梗死体积减小,对脑缺血-再灌注损伤的脑组织有保护作用。     

眼针与体针对急性脑缺血再灌注损伤大鼠脑皮质脑源性神经营养因子表达的影响

目的分别观察眼针与体针对急性脑缺血再灌注损伤大鼠脑源性神经营养因子(BDNF)表达的影响,探讨眼针疗法与体针疗法的效应差异性,为眼针疗法自成诊疗体系提供相关依据。方法线栓法制备SD大鼠大脑中动脉梗死(MCAO)再灌注模型。将SD大鼠随机分为六组,即正常对照组、假手术组、模型组、眼针穴区组、眼针穴区外组与体针组。采用Zea Longa评分法进行大鼠神经功能评分;实时定量PCR方法检测缺血再灌注3 h后脑皮质BDNF mRNA的表达;Western印迹法检测缺血再灌注3 h后脑皮质BDNF蛋白的表达。结果脑缺血再灌注3 h后,眼针穴区组和体针组大鼠神经功能缺损评分较模型组大鼠降低(P0.01),眼针穴区组与体针组相比差异无统计学意义(P0.05);眼针穴区组、体针组和眼针穴区外组较模型组大鼠脑皮质BDNF mRNA和蛋白质含量均升高(P0.01),但以眼针穴区组和体针组升高较明显,眼针穴区组与体针组比较无统计学差异(P0.05)。结论眼针与体针在改善急性脑缺血再灌注损伤中的效应相当,且两种疗法的作用机制可能与上调脑皮质BDNF表达有关。     

艾芬地尔对大鼠脑缺血再灌注后Survivin表达的影响

目的探讨大脑中动脉缺血再灌注后缺血侧海马区Survivin的表达规律及艾芬地尔对大鼠脑缺血再灌注后不同时相Survivin表达的影响。方法 72只Wistar大鼠随机分为假手术组、模型组和艾芬地尔干预组,采用线拴法制作局灶性大鼠脑缺血再灌注模型,假手术组于术后,模型组和艾芬地尔干预组于脑缺血2 h分别再灌注3 h、24 h、72 h及7天后处死取材,免疫荧光法测量不同时相缺血侧海马神经元Survivin的表达。结果假手术组Survivin呈现少基础量表达,模型组和艾芬地尔干预组Survivin表达规律基本一致,即在再灌注3 h时表达即有升高,至72 h达到高峰,7天表达有所下降,与假手术组比较差异显著(P0.05);艾芬地尔干预组荧光强度值明显高于对应模型组(P0.05)。结论大脑中动脉缺血再灌注后Survivin的表达升高,72 h达高峰;艾芬地尔对大脑中动脉缺血再灌注损伤具有保护作用。     

黄体酮对大鼠局灶性脑缺血再灌注损伤后脑组织神经生长因子表达的影响

目的 观察黄体酮对大鼠局灶性脑缺血-再灌注损伤后缺血区皮层神经生长因子(NGF)和脑源性神经营养因子(BDNF)在mRNA与蛋白质水平表达的影响,探讨黄体酮在脑缺血-再灌注损伤中的脑保护作用机制. 方法 采用SD雄性大鼠局灶性脑缺血-再灌注损伤模型.将96只大鼠随机分为4组:假手术组、缺血再灌注组、溶剂组和黄体酮组各24只.应用Real time-PCR和Western blot技术分别对缺血区皮层NGF和BDNF mRNA与蛋白表达情况进行测定. 结果 在缺血区皮层,缺血2h再灌注6h后,缺血再灌注组NGF和BDNF的mRNA及蛋白质表达达高峰,再灌注24 h后,回复到假手术组水平;缺血2h再灌注12 h后,黄体酮组NGF和BDNF mRNA及蛋白表达达高峰,再灌注24 h后,表达仍高(P＜0.05). 结论 黄体酮可以使脑缺血-再灌注损伤后NGF和BDNF的mRNA表达上调,促进脑内NGF和BDNF蛋白的合成,从而发挥脑保护作用.     

大鼠局灶性脑缺血再灌注后肿瘤坏死因子表达的变化及三七总皂苷的作用研究

目的研究三七总皂苷（PNS）对局部脑缺血再灌注后脑组织中肿瘤坏死因子（TNF-α）的影响,探讨PNS对缺血再灌注后神经元的保护作用。方法参照Zea Longa线栓法制作大鼠大脑中动脉阻塞模型（MCAO）,100只SD大鼠随机分成假手术组、缺血再灌组和PNS治疗组。每组大鼠再随机分成4组,分别在再灌注后6h,24h,48h,96h处死。用免疫组化法检测缺血脑组织冷冻切片TNF-α的阳性表达。结果假手术组脑内有极少量表达;缺血再灌组与PNS治疗组各时间点表达明显强于假手术组（P〈0.01）,PNS治疗组各时间点表达弱于缺血再灌组,阳性细胞数亦明显减少（P〈0.01）。结论三七总皂苷对脑缺血再灌注后TNF-α的表达有降低趋势。     

脑缺血预处理对缺血再灌注大鼠三叉神经诱发电位的影响

目的观察脑缺血预处理对缺血再灌注大鼠三叉神经诱发电位的影响。方法40只Wistar大鼠,随机等分4组,采用线栓法闭塞大脑中动脉,建立可逆性局灶性脑缺血再灌注模型。假手术组:只做手术操作;单纯预处理组:缺血15min后恢复血流;预处理后缺血组:15min缺血预处理后恢复血流2d,再次缺血2h再灌注1d;假手术后缺血组:假手术后2d缺血2h再灌注1d。第4天观察各处理组诱发电位及组织学变化。结果单纯预处理组与假手术组比较波幅、潜伏期及组织学分级无显著性差异;随组织损伤的加重,三叉神经诱发电位波幅降低,潜伏期延长,假手术后缺血组比预处理后缺血组潜伏期延长,波幅下降,组织学分级升高,有显著性差异。结论脑缺血预处理后三叉神经诱发电位潜伏期和波幅的变化与组织学改变基本一致,其监测方法创伤小,重复性好,是研究脑缺血预处理有效可靠的手段。     

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.