血清应答因子在血管新生内膜形成过程中的表达变化

目的探讨SRF与VSMC表型转化及增殖之间的关系。方法建立大鼠颈总一胸腹主动脉内皮剥脱后内膜增生模型，应用Northern印迹、Western印迹及免疫组化等方法从RNA和蛋白质水平上检测新生内膜形成过程中SRF表达的动态变化。结果血管内皮剥脱后3d，可见局部内膜增生，中膜平滑肌细胞排列不齐；术后7～14d，内膜呈进行性弥漫增厚，管腔出现狭窄。在增生的内膜中，SRF的mRNA和蛋白水平明显升高，于术后7d达高峰，其动态变化模式与血管内膜增厚速率相一致，但与收缩型VSMC的标志物SM22α的表达却呈反相关变化。结论血管内皮剥脱后SRF表达活性升高与VSMC去分化和新生内膜形成具有直接关系。     

大鼠颈动脉球囊损伤后血管平滑肌细胞E1A激活基因阻遏子的表达变化

目的探讨血管再狭窄发生的病理生理机制及E1A激活基因细胞阻遏子(CREG)在新生内膜增殖中的调控作用, 为研究CREG防治增生性血管疾病的作用奠定基础.方法采用大鼠颈动脉球囊损伤后血管再狭窄的动物模型, 以免疫组织化学染色、逆转录-聚合酶链反应(RT-PCR)方法, 检测新生内膜中增殖细胞核抗原(PCNA)和平滑肌α肌动蛋白(SM α-actin)的表达变化及血管壁中CREG mRNA水平、蛋白表达的动态变化.结果大鼠颈动脉球囊损伤后1 d血管壁 CREG mRNA水平开始下降, 至损伤后5 d达最低, 损伤后7 d CREG mRNA表达回升, 至28 d时仍未回到正常对照组的水平.血管损伤后3 d血管内表面可见增殖的血管平滑肌细胞(VSMC), PCNA染色阳性, 其胞浆内SM α-actin和CREG染色均为阴性; 损伤后5 d新生内膜形成并增厚, PCNA阳性细胞数达到高峰, 部分VSMC胞浆内SM α-actin和CREG染色均呈阳性; 损伤后28 d管腔严重狭窄, 新生内膜中PCNA表达已较低, SM α-actin和CREG表达均明显增加, 新生内膜SM α-actin表达程度仍弱于中膜, CREG表达程度接近中膜.损伤后不同时间点VSMC增殖程度与血管壁中CREG mRNA水平的变化呈负相关(r=-0.80, P<0.05), CREG mRNA的表达为先降低, 后回升, 而细胞增殖指数为先升高, 后回降.结论 VSMC的表型转化、增殖、迁移和分泌细胞外基质导致新生内膜过度增生和管腔狭窄, CREG参与VSMC增殖的调控.     

黄芪和当归对血管平滑肌细胞表型标志基因表达和细胞增殖的影响

为了观察黄芪和当归对血管平滑肌细胞表型转化和增殖的影响，采用体外培养的血管平滑肌细胞，以碱性成纤维细胞生长因子诱导其表型转化和增殖，在此基础上，通过Northern和Western印迹法检测平滑肌细胞表型标志基因表达的变化，研究黄芪和当归注射液对碱性成纤维细胞生长因子上述效应的抑制作用。结果发现，碱性成纤维细胞生长因子可明显下调分化型标志基因平滑肌α-肌动蛋白的表达，上调去分化型标志基因平滑肌胚胎型肌球蛋白重链和骨桥蛋白表达，诱导原癌基因c-jun表达及促进血管平滑肌细胞DNA合成。黄芪和当归可上调分化型标志基因的表达活性，下调去分化型标志基因的表达，不同程度地抑制碱性成纤维细胞生长因子诱导的血管平滑肌细胞表型转化和DNA合成，有效抑制血管平滑肌细胞增殖，其作用机制可能与抑制碱性成纤维细胞生长因子诱导的c-jun基因表达有关。二者相比，当归的作用大于黄芪。结果提示，黄芪和当归可从多位点上拮抗碱性成纤维细胞生长因子促血管平滑肌细胞表型转化及细胞增殖。     

几丁聚糖对大鼠颈动脉球囊损伤术后血管内膜增生的影响

目的研究几丁聚糖对大鼠颈动脉球囊损伤术后再狭窄的影响,并探讨其机制。方法60只SD大鼠分为几丁聚糖组和模型组各30只。复制大鼠颈动脉球囊损伤模型。几丁聚糖组在术前1周即开始每天一次灌胃几丁聚糖2g,并在术后继续给予至处死;模型组只建立模型但不予以任何处理。分别于手术后即刻(0d)、7d、14d、28d和35d,每组各处死大鼠6只。光镜下观察血管内膜损伤;运用图形分析系统检测增殖的内膜面积;α肌动蛋白免疫组织化学检测增殖内膜细胞的性质,血管内皮生长因子免疫组织化学标记血管内皮细胞明确损伤后血管内皮修复情况。结果模型复制成功53例,几丁聚糖组28例,模型组25例。手术后即刻见血管内膜完全剥脱,部分可见平滑肌细胞断裂。手术后7d可见内膜增生。模型组血管内膜在第28天增生达高峰,几丁聚糖组内膜增生在术后14d达到高峰。几丁聚糖组与模型组比较内膜增生程度差异有显著性(P均<0.05)。α肌动蛋白检测结果显示增殖的内膜细胞为血管平滑肌细胞。血管内皮生长因子检测结果显示几丁聚糖组在手术后14d血管完全再内皮化,而模型组手术后28d才完全再内皮化。结论几丁聚糖能预防大鼠颈动脉球囊损伤术后再狭窄,其机制可能与几丁聚糖促进血管再内皮化有关。     

高脂血症对内皮剥脱术后血管炎症反应的影响

目的探讨高脂血症对内皮剥脱术后血管炎症反应的影响。方法建立大鼠主动脉内皮剥脱后内膜增生模型,利用免疫组化及Western blot方法检测血管壁NF-κB和iNOS的表达变化,并结合形态学分析研究高脂血症大鼠内皮剥脱后血管炎症反应及新生内膜增生情况。结果主动脉内皮剥脱后内膜呈弥漫性增厚,管腔变小,增厚的内膜以VSMC为主,中膜VSMC排列紊乱。高脂血症明显促进了增生的内膜中NF-κB和iNOS的表达。结论高脂血症通过促进NF-κB表达进而诱导iNOS的表达,加剧了内皮剥脱后的血管炎症反应。     

大鼠局灶性脑缺血再灌注小动脉血管平滑肌细胞表型转化的实验研究

目的　观察大脑中动脉缺血再灌注大鼠模型小动脉血管平滑肌细胞 (VSMC)中两种血管舒缩功能相关蛋白(α 平滑肌肌动蛋白和细丝蛋白 )的免疫组织化学表达变化 ,以期了解脑小动脉病变中VSMC的表型转化及细丝蛋白在表型转化中的意义 ,指导临床小动脉硬化型脑卒中的准确防治。方法　缺血再灌注组依照再灌注时间的不同分为 2、6、12、2 4h、3d及 7d共 6个亚组 ,另设正常对照组及大脑中动脉持续缺血组。按时相点取材 ,免疫组织化学染色 ,图像分析。结果　α 平滑肌肌动蛋白在再灌注 6h后表达明显下降 ,在 2 4h时表达最低 ,在 3d时表达有所升高 ,7d时表达最高 ;细丝蛋白缺血 2h后表达稍有下降 ,以 12h时的表达最低 ,2 4h时表达升高 ,在 3d时表达最高。结论　再灌注损伤可引起小动脉VSMC表型的变化 ;细丝蛋白也可作为VSMC表型变化的指标之一 ,与α 平滑肌肌动蛋白相比意义更大 ;细丝蛋白和α 平滑肌肌动蛋白可能在再灌注中起下调炎症反应及保护细胞的作用     

粉防己碱对内膜损伤后平滑肌细胞表型转化和MKP-1表达的影响

目的研究粉防己碱（tetrandrine,Tet）在防治血管内膜损伤后再狭窄（RS）与血管平滑肌细胞（VSMC）表型转化及丝裂原激活蛋白激酶磷酸酶-1（MKP-1）表达之间的关系。方法采用HE染色检测假损伤组（S组）、损伤组（I组）和损伤+Tet治疗组（Tet组）28 d血管形态学改变;分别使用免疫组化和RT-PCR技术检测I组和Tet组7、14、28 d增殖细胞核抗原（PCNA）、平滑肌α-肌动蛋白（SMα-actin）和MKP-1表达的变化。结果①28 d血管形态观察,S组血管壁各层结构完整;I组新生内膜（neointim a,NI）面积显著增加,管腔面积（LA）显著缩小;Tet组NI增殖较I组明显减轻,LA增加。②损伤后7 d,Tet组与I组之间血管壁SMα-actin、PCNA和MKP-1表达变化无显著差异,NI增殖程度亦基本相同。Tet组14 d和28 d血管壁中PCNA表达均低于I组,而MKP-1表达均高于I组;14d SMα-actin表达略高于I组,28 d两组间无差异。结论Tet可不同程度地拮抗内膜损伤后VSMC表型转化及其调节,继而减缓NI增殖。     

丝裂原激活蛋白激酶磷酸酶-1和p38在内膜损伤后血管平滑肌细胞表型转化过程中的表达变化

目的:观察动脉内膜损伤后血管平滑肌细胞(VSMC)表型转化和p38MAPK及丝裂原激活蛋白激酶磷酸酶-1(MKP-1)表达的动态变化。方法:分别用免疫组化、免疫印迹(Westernblot)和逆转录-聚合酶链反应方法检测假损伤组(S组)和损伤组损伤后不同时间点血管壁中增殖细胞核抗原(PCNA)、平滑肌α肌动蛋白(SMα-actin)、p38蛋白和MKP-1mRNA及蛋白表达的变化。结果:①S组中膜VSMC及内皮细胞PCNA为阴性表达;中膜于损伤后1~14d,新生内膜(NI)于5~14d阳性细胞率逐渐增加,28d后开始逐渐减少,NI阳性率高于中膜。②S组中膜SMα-actin表达为阳性,内皮为阴性;中膜阳性表达于损伤后1d开始减少,3d最为明显,5d后开始逐渐增加,NI阳性表达弱于中膜。③S组中膜p38呈阴性或弱阳性;损伤后1~35d呈持续高表达,NI阳性表达强于中膜。p38与PCNA表达变化呈正相关。④S组中膜MKP-1呈弱阳性或阳性表达;损伤后1d即开始下降,14~28d稍有回升,至35d仍未回到S组水平,NI阳性表达稍弱于中膜。MKP-1与PCNA表达变化呈负相关。结论:VSMC增殖能力与其表型转化密切相关,p38MAPK和MKP-1参与了损伤后VSMC表型转化的信号转导及其调节。     

舒心益脉煎对气滞血瘀型大鼠动脉内膜损伤后细胞凋亡及基因蛋白产物的影响

探讨气滞血瘀型大鼠胸主动脉内膜剥脱后内膜增生中，舒心益脉煎对血管平滑肌细胞凋亡及相关基因Fas抗原和Fas配体的影响。将58只大鼠随机分为假且10只，舒心益脉煎组和对照组各24只。后两组大鼠行胸主动脉内膜剥脱术，舒心益脉煎组动物于术前7d至术后14d每日接受舒心益脉煎治疗。术后14d处死动物，用免疫组织化学法测定Fas抗原与Fas配体在血管中的表达，原位末端标记法测定凋亡细胞。术后14d血管新生内膜中有平滑肌细胞凋亡；舒心益脉煎显著增加新生内膜中Fas抗原与Fas配体的表达，增加血管平滑肌细胞凋亡，减少新生内膜面积。说明舒心益脉煎可能通过Fas系统调节动脉血管内皮损伤修复过程中血管平滑肌细胞凋亡，从而抑制新生内膜形成。     

动脉内膜损伤后血管平滑肌细胞表型转化及MKP-1表达的变化

目的:观察动脉内膜损伤后血管平滑肌细胞（vascu lar smooth musc le cells,VSMC）表型转化和丝裂原激活蛋白激酶磷酸酶-1（m itogen-activated prote in k inase phosphatase-1,MKP-1）表达的动态变化。方法:分别用HE染色、免疫组化和逆转录-聚合酶链（RT-PCR）方法检测假损伤组（S组）和损伤后不同时间点血管形态学改变及血管壁中增殖细胞核抗原（PCNA）、平滑肌α肌动蛋白（SMα-actin）和MKP-1 mRNA及蛋白表达的变化。结果:①损伤后1 d中膜腔侧、3 d管腔内表面可见增殖的VSMC,57 d新生内膜（neointim a,NI）形成并逐渐增厚,1435 d NI进行性增厚;各组中膜均有增殖的VSMC向腔面集聚。②S组中膜VSMC及内皮细胞PCNA为阴性;中膜于损伤后114d,NI于514 d PCNA阳性细胞率逐渐增多,14 d达高峰,28 d后开始逐渐减少,但NI阳性率多于中膜。③S组中膜SMα-actin表达为阳性,内皮为阴性;中膜阳性面积于损伤后1 d开始减少,3 d最为明显,5 d后开始逐渐增加,NI阳性表达弱于中膜。④S组中膜MKP-1呈弱阳性或阳性表达,损伤后1d即开始下降,57 d达最低,14 d稍有回升,至35 d仍未回到假损伤组水平;NI阳性表达弱于中膜。MKP-1表达变化与PCNA表达变化呈负相关。结论:VSMC增殖能力与其表型转化密切相关,MKP-1参与了损伤后VSMC表型转化的调节。     

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.