丁基苯酞对缺血性脑损伤模型大鼠血脑屏障的影响

目的观察大鼠全脑缺血后血脑屏障的改变以及丁基苯酞的干预作用,探讨其对缺血性脑损伤的防护作用机制。方法选择120只SD大鼠,随机分为假手术组24只、脑缺血组24只、丁基苯酞组72只。采用四血管结扎的全脑缺血模型,制模成功后丁基苯酞组大鼠按腹腔注射剂量又分为丁基苯酞0.3 mg/kg组24只、丁基苯酞1.0mg/kg组24只、丁基苯酞3.0 mg/kg组24只;检测脑组织依文思蓝(EB)含量、免疫组织化学法检测脑组织血管内皮生长因子(VEGF)表达、心脏取血计数循环内皮细胞数。结果与假手术组比较,脑缺血组大鼠脑组织EB含量、VEGF表达、循环内皮细胞数明显升高(P<0.05,P<0.01);与脑缺血组比较,丁基苯酞各剂量组大鼠脑组织EB含量、VEGF表达、循环内皮细胞数明显降低,以丁基苯酞3.0 mg/kg组最明显(P<0.05,P<0.01)。结论丁基苯酞通过降低大鼠全脑缺血后脑组织VEGF表达、降低循环内皮细胞数,从而降低血脑屏障的通透性,对缺血性脑损伤有保护作用。     

肌苷对脑缺血再灌流损伤神经功能恢复和NSE表达的影响

目的　观察大鼠脑缺血再灌流损伤脑组织神经元特异性烯醇化酶 (NSE)的变化规律及其意义 ;探讨肌苷对缺血性脑损伤的保护机制。方法　用成年 SD大鼠建立大脑中动脉缺血 (MCAO)再灌流模型 ,腹腔注射肌苷注射液 ,应用神经功能等级评分观察脑缺血再灌流后行为功能的恢复 ,免疫组化法检测脑缺血再灌流各时间点脑组织中 NSE的动态变化。结果　对照组脑缺血再灌流后 3d、7d、1 4 d功能恢复、等级评分减低 ;缺血侧 NSE的免疫阳性反应于脑缺血再灌流后 1 2 h明显增强并达高峰 ,随时间推移逐渐下降 ,至 1 4 d降至假手术组水平。治疗后神经功能评分在 7～1 4 d明显低于对照组 ,同时脑组织中 NSE蛋白表达水平较对照组显著升高。两组中皮层区 NSE的免疫阳性反应均高于纹状体区。结论　肌苷对缺血性脑损伤的功能恢复有一定的促进作用 ,其机制可能与增加脑组织中 NSE的表达有关     

丁基苯酞对脑缺血大鼠大脑皮质水通道蛋白4表达的影响

目的观察丁基苯酞对脑缺血大鼠大脑皮质水通道蛋白4(AQP4)表达的影响,探讨其对缺血性脑损伤的防护作用机制。方法选择SD大鼠140只,采用四血管结扎的大脑中动脉闭塞模型,将制模成功后48只大鼠随机分为脑缺血组24只、丁基苯酞组24只;另选24只为假手术组。丁基苯酞组按剂量又分为0.3mg/kg组、1.0mg/kg组、3.0mg/kg组,各组8只。分别于1d、1周和1个月测定脑组织依文思蓝(EB)含量和脑含水量;免疫组织化学法检测AQP4蛋白表达。结果与假手术组比较,脑缺血组大鼠1d、1周脑组织EB含量和脑含水量明显升高、AQP4表达明显降低,差异有统计学意义(P<0.05,P<0.01);与脑缺血组比较,丁基苯酞组1d、1周脑组织EB含量和脑含水量明显降低、AQP4表达有不同程度升高,差异有统计学意义(P<0.05,P<0.01)。结论大鼠脑缺血后AQP4表达呈现时程性变化,丁基苯酞对AQP4有调节作用。     

核转录因子κB抑制剂缓解大鼠局部脑缺血后脑损伤

目的探讨NF-κB抑制剂在大鼠缺血性脑损伤中的作用。方法 116只Wistar大鼠,随机选98只采用改良的大脑中动脉栓塞法制作脑缺血模型后,分为实验组(44只,腹腔注射吡咯烷二硫代氨基甲酸盐0.5 ml)、PBS组(24只)和缺血组(30只),未做脑缺血模型的18只为正常组。记录各组大鼠脑组织水分含量,HE染色检测脑梗死程度,Western blot检测NF-κB p65、白细胞介素(IL)6、IL-1b表达。结果与正常组比较,缺血组大鼠脑组织水分含量明显增多,NF-κB p65明显增加(P0.05)。与缺血组比较,实验组大鼠脑组织水分含量明显降低,NF-κBp65表达明显降低(P0.05)。与缺血组和PBS组比较,实验组大鼠脑梗死面积明显减少,IL-6、IL-1b表达减少(P0.05)。结论抑制NF-κB能够减轻缺血后脑损伤,其机制可能通过抑制脑缺血后炎性反应起作用。     

组织芯片中文文献的统计分析

组织芯片(组织微阵列)一般是指将数十至上千个小组织整齐地排放在一张载玻片上而制成的组织切片.组织芯片蜡块可做100～200张连续切片,这样用同一套组织芯片即可对上百种生物分子标记(如抗原,DNA和RNA)进行分析、检测,因而倍受组织病理学家的重视[1].1998年Kononen等[2]首次采用组织芯片技术将645例乳脾癌组织固定于载体上,同时进行多种基因的检测,从此,众多学者开始对组织芯片技术进行研究,组织芯片技术不断发展和完善,其应用也愈来愈广泛[3～9].     

CD_8T淋巴细胞在大鼠缺血再灌注脑组织中表达的变化

目的观察大鼠大脑中动脉闭塞(middle cerebral artery occlusion,MCAO)脑缺血模型再灌注不同时间点的脑组织中CD8T淋巴细胞表达的动态变化,探讨CD8T淋巴细胞与缺血性脑损伤的关系。方法选择成年雄性SD大鼠35只,随机分为假手术组,缺血再灌注24h、3d、5d、7d、10d和14d组,每组5只。采用Zea-Longa线栓法制作大鼠MCAO脑缺血模型,HE染色显示脑缺血再灌注组织病理学形态,SP法免疫组织化学染色显示CD8分子表达的变化,光镜下计数CD8T淋巴细胞数。结果再灌注7d和10d组,脑组织大量神经元细胞质、胞核界限模糊、核固缩溶解,细胞间出现大小不等的空泡。CD8T淋巴细胞于再灌注24h组即开始表达,再灌注7、10d组达到高峰,随后下降。再灌注各时间点组CD8T淋巴细胞数显著高于假手术组(P<0.01)。CD8T淋巴细胞大量表达于缺血再灌注脑组织,且主要分布于脑梗死边缘区。结论 CD8T淋巴细胞参与了脑缺血再灌注损伤。     

激活素A对新生大鼠缺血缺氧后脑组织巢蛋白表达的影响

目的探讨激活素A对新生大鼠缺氧缺血性脑损伤(HIBD)脑组织巢蛋白的表达变化。方法将7日龄Wistar大鼠120只随机分为3组,假手术组、缺氧缺血性脑损伤(HIBD)模型组和激活素A治疗组,每组各40只。每组根据处死的时间不同又分为5个亚组:6h组、24h组、3d组、7d组、14d组,每亚组各8只。HE染色观察神经细胞形态变化,采用免疫组化的方法测定巢蛋白的表达。结果HIBD组缺氧缺血侧大脑组织巢蛋白活性逐渐增高,3d显著增高,7d达高蜂,然后逐渐下降,14d仍有少量表达;与HIBD模型组各时间点相比,激活素A治疗组各时间点脑组织巢蛋白表达明显增高(P0.01)。结论激活素A治疗增高缺氧缺血后巢蛋白的表达,对缺氧缺血性脑损伤有保护作用。     

Esculetin对缺血性脑损伤大鼠神经的保护作用

目的探讨Esculetin(ESC)对缺血性脑损伤大鼠的神经保护作用及可能机制。方法通过线栓法建立大鼠脑缺血再灌注模型,并对大鼠神经功能进行评分;将大鼠模型均分为ESC处理组和模型组,其中ESC处理组大鼠通过灌胃给予ESC,而模型组给予等量的生理盐水;通过2,3,5-氯化三苯基四氮唑(TTC)染色显示梗死面积,观察ESC对缺血再灌注损伤后脑组织形态的改变;通过酶联免疫吸附试验(ELISA)检测脑组织Toll样受体(TLR)4、核因子(NF)-κB、胶质细胞源性生长因子(GDNF)表达;采用黄嘌呤氧化酶-羟胺法测定脑组织超氧化物歧化酶(SOD)活性,硫代巴比妥酸法测定脑组织丙二醛(MDA)含量。结果对大鼠模型进行评分,其中1～3分视为造模成功,造模成功率为89.41%。与模型组比较,ESC处理组大鼠脑梗死面积显著降低,脑组织TLR4、NF-κB表达显著降低,MDA活性显著下降,而SOD活性及GDNF表达显著上升(均P0.05)。结论 ESC可通过降低TLR4、NF-κB、MDA含量,升高GDNF表达及SOD活性对缺血性脑损伤大鼠发挥神经功能的保护作用,其机制可能与炎症反应的降低及抗氧化能力的提高相关。     

活血开窍法对脑缺血再灌注损伤大鼠脑组织兴奋性氨基酸的影响

目的观察活血开窍法对大鼠脑缺血再灌注损伤脑组织兴奋性氨基酸(EAA)的影响。方法以大鼠局灶性脑缺血再灌注模型为研究对象,于缺血2h再灌注48h,取脑组织应用高效液相色谱法测定谷氨酸(Glu)、天门冬氨酸(Asp)的含量。结果缺血2h再灌注48h后,模型组、药物组与正常组大鼠比较,脑组织G1u及Asp含量升高(P0.01);与模型组大鼠比较,醒脑通脉大、小剂量组脑组织中Glu、Asp含量显著降低(P0.01)。结论活血开窍法抗缺血性脑损伤的作用机制可能与其对抗脑缺血再灌注后EAA的升高有关。     

脑缺血后大鼠血管内皮生长因子与神经发生的形态学研究

目的观察缺血性脑损伤后大鼠海马内源性血管内皮生长因子(VEGF)表达与海马齿状回神经发生的相关性。方法将24只雄性SD鼠随机分为脑缺血组(21只)和假手术组(3只),脑缺血组大鼠通过改良的4血管闭塞法建立缺血性脑损伤模型,于6、12、24 h和3、6、12和24天,用免疫组织化学及荧光双标记染色法观察不同时间点大鼠海马内源性VEGF表达及神经发生水平。结果脑缺血组大鼠海马区内源性VEGF表达主要集中于海马齿状回和门区,亚颗粒增生带可见丛集VEGF表达阳性细胞;海马齿状回神经发生水平于缺血后第3天时较假手术组升高,于6天时达到峰值(P<0.01)。缺血后早期海马VEGF表达多见于神经元细胞质,在缺血后期则主要见于胶质细胞质。结论大鼠脑缺血后,来源于海马齿状回神经元的VEGF表达可能是缺血诱导的齿状回神经发生水平上调的一个重要始动信号,胶质细胞表达的内源性VEGF表达可能参与了齿状回神经发生的后续过程。     

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.