波动性高糖对血管平滑肌细胞增殖及凋亡蛋白表达的影响

目的探讨波动性高葡萄糖对血管平滑肌细胞增殖及凋亡蛋白表达的影响。方法以持续高糖和波动性高糖分别孵育大鼠胸主动脉平滑肌细胞24 h,采用MTT法检测血管平滑肌细胞增殖活性,流式细胞术检测细胞周期改变,Western bloting检测胞浆中Bcl-2、Bax蛋白的表达。结果波动性高浓度葡萄糖(5.5 mmol/L和25mmol/L交替)培养较持续高浓度葡萄糖(25 mmol/L)培养可明显增加血管平滑肌细胞增殖活性,促进其由G0/G1期向S期转变,上调Bcl-2/Bax比值。结论波动性高葡萄糖可能通过干预细胞周期及对凋亡蛋白的调控,进一步促进血管平滑肌细胞增殖,诱导其凋亡,因而较持续性高葡萄糖更能促进糖尿病动脉粥样硬化的发生发展。     

罗格列酮对高糖诱导大鼠胸主动脉平滑肌细胞增殖和凋亡的影响

目的 研究罗格列酮(RGZ)对高浓度葡萄糖(高糖)孵育下的血管平滑肌细胞(VSMCs)增殖和凋亡的影响. 方法 VSMCs取自大鼠胸主动脉.MTT法检测细胞增殖活性,流式细胞术检测VSMCs细胞周期、凋亡率及Bcl-xl、Bcl-2蛋白表达,Western blot检测VSMCs Bcl-xl蛋白表达. 结果 高糖(Glu 11.2、22.4 mmol/L)培养可明显促进VSMCs增殖,抑制其凋亡;30及100 μmol/L RGZ以浓度依赖形式抑制高糖孵育下VSMCs增殖活性,阻止其由G0/G1期向S期转变,降低VSMCs Bcl-xl、Bcl-2表达,并促进其凋亡; RGZ拮抗剂GW9662预处理可部分拮抗RGZ的作用. 结论 RGZ可通过对细胞周期的干预,抑制高糖诱导的VSMCs增殖,下调Bcl-xl、Bcl-2表达,促进VSMCs凋亡,在2型糖尿病大血管病变的防治中发挥重要作用.     

辣椒素对高盐致大鼠血管平滑肌细胞增殖的抑制作用

目的研究辣椒素对高盐诱导的大鼠血管平滑肌细胞(VSMC)增殖的抑制作用。方法组织贴壁法培养原代大鼠血管平滑肌细胞,根据MTT结果绘制大鼠血管平滑肌细胞的生长曲线,大鼠血管平滑肌细胞传至第4代去血清同步化24 h,不同浓度辣椒素(0.01μmol/L、0.1μmol/L、1μmol/L、10μmol/L、100μmol/L)进行高盐培养72 h,MTT比色法检测大鼠血管平滑肌细胞增殖情况,选取抑制血管平滑肌细胞增殖的辣椒素浓度进行后续实验。CCK-8检测渗透压对大鼠血管平滑肌细胞增殖的影响,流式细胞仪分析细胞增殖周期,免疫荧光染色法和Western blot检测增殖细胞核抗原(PCNA)的表达,实时荧光定量PCR检测瞬时受体电位家族香草醛1型受体(TRPV1)mRNA的表达,Western blot检测瞬时受体电位家族香草醛1型受体的蛋白表达。结果 MTT结果显示,辣椒素浓度为10μmol/L时大鼠血管平滑肌细胞增殖开始受抑制,100μmol/L时抑制作用增强(P0.05),选取10μmol/L辣椒素进行后续实验。CCK-8结果显示,高盐组细胞明显增殖,而甘露醇组、正常组和高盐+辣椒素组无差异。流式细胞仪测得高盐组G0/G1、G2/M期细胞比例减少(P0.05),S期细胞比例增多(P0.05);与高盐组比较,高盐+辣椒素组G0/G1、G2/M期细胞比例增加(P0.05),S期细胞比例下降(P0.05)。免疫荧光及Western blot结果显示,高盐组增殖细胞核抗原阳性细胞核增多,蛋白表达增加(P0.05),而高盐+辣椒素组增殖细胞核抗原阳性细胞核减少,蛋白表达减少(P0.05)。实时荧光定量PCR和Western blot结果显示高盐组瞬时受体电位家族香草醛1型受体mRNA及蛋白表达减少(P0.05),辣椒素组则增加(P0.05)。结论辣椒素可抑制高盐所致的大鼠血管平滑肌细胞增殖,其作用机制可能与激活瞬时受体电位家族香草醛1型受体表达有关。     

可罗卡林对血管平滑肌细胞增殖及c-myc基因表达的影响

目的：观察对大鼠主动脉平滑肌细胞起负调节作用的可罗卡林(cromakalim对同型半胱氨酸(hcy)刺激的血管平滑肌细胞(vascular smooth muscle cells，VSMC)增殖及c—myc基因表达的影响。方法：在建立hcy诱导的平滑肌细胞增殖模型后，应用流式细胞术观察VSMC增殖周期的变化；并用免疫细胞化学方法观察可罗卡林对VSMC增殖及c—myc基因蛋白表达的影响。结果：可罗卡林使VSMC处于G0／G1期的细胞数显著增多(P＜0．01)，S期G2 M期的细胞数显著减少(P＜0．01．)，能够抑制hcy诱导的VSMC增殖和c—myc基因蛋白表达的增加。结论：可罗卡林对hcy诱导的VSMC增殖有显著的抑制作用，其作用机制与抑制c—myc基因表达有关。     

阿托伐他汀对高葡萄糖诱导的血管平滑肌细胞增殖的抑制作用

目的研究阿托伐他汀对醛糖还原酶(AR)和核因子NF-κB的表达及血管平滑肌细胞增殖的影响,探讨阿托伐他汀抗细胞增殖的可能机制.方法用高浓度葡萄糖诱导大鼠血管平滑肌细胞(VSMC)AR基因表达,然后加入不同浓度的阿托伐他汀,培养3 d后用台盼蓝染色行细胞计数.并采用RT-PCR、免疫组化、原位杂交等方法,观察阿托伐他汀对NF-κB和AR基因表达及VSMC增殖的影响.结果 1)随着阿托伐他汀浓度的提高,VSMC计数逐渐减少.2)正常浓度葡萄糖(5.6 mmol/L)时, NF-κB表达不明显,高浓度葡萄糖(22.5 mmol/L)时,NF-κB表达强阳性,阿托伐他汀则可明显抑制这一表达,0.1 μmol/L阿托伐他汀时, NF-κB表达即有降低,10 μmol/L阿托伐他汀几乎完全抑制NF-κB的表达.3)高浓度葡萄糖可明显诱导AR基因的表达,阿托伐他汀对其表达有抑制作用,且呈剂量依赖性.与高浓度葡萄糖组相比,阿托伐他汀0.1、1、10 μmol/L分别使VSMC的AR mRNA下调12%、45%和80%(P均＜0.05).结论 1)阿托伐他汀可抑制VSMC增殖.2)阿托伐他汀可抑制AR及NF-κB的表达.3)阿托伐他汀可能是通过抑制AR及NF-κB的表达继而抑制VSMC的增殖.     

阿托伐他汀对高葡萄糖诱导的血管平滑肌细胞增殖的抑制作用

目的研究阿托伐他汀对醛糖还原酶(AR)和核因子NF-κB的表达及血管平滑肌细胞增殖的影响,探讨阿托伐他汀抗细胞增殖的可能机制。方法用高浓度葡萄糖诱导大鼠血管平滑肌细胞(VSMC)AR基因表达,然后加入不同浓度的阿托伐他汀,培养3d后用台盼蓝染色行细胞计数。并采用RT-PCR、免疫组化、原位杂交等方法,观察阿托伐他汀对NF-κB和AR基因表达及VSMC增殖的影响。结果1)随着阿托伐他汀浓度的提高,VSMC计数逐渐减少。2)正常浓度葡萄糖(5·6mmol/L)时,NF-κB表达不明显,高浓度葡萄糖(22·5mmol/L)时,NF-κB表达强阳性,阿托伐他汀则可明显抑制这一表达,0·1μmol/L阿托伐他汀时,NF-κB表达即有降低,10μmol/L阿托伐他汀几乎完全抑制NF-κB的表达。3)高浓度葡萄糖可明显诱导AR基因的表达,阿托伐他汀对其表达有抑制作用,且呈剂量依赖性。与高浓度葡萄糖组相比,阿托伐他汀0·1、1、10μmol/L分别使VSMC的ARmRNA下调12%、45%和80%(P均<0·05)。结论1)阿托伐他汀可抑制VSMC增殖。2)阿托伐他汀可抑制AR及NF-κB的表达。3)阿托伐他汀可能是通过抑制AR及NF-κB的表达继而抑制VSMC的增殖。     

姜黄素对血管平滑肌细胞增殖及cyclinD1和p21wafl/cipl蛋白表达的影响

目的 观察姜黄素(curcumin)抑制大鼠血管平滑肌细胞(VSMC)增殖和诱导细胞周期停滞的作用,以及对细胞周期蛋白cyclinDl,p21wafl/cipl表达的影响.方法 采用组织贴块法体外培养大鼠VSMC,MTT法测定姜黄素对VSMC增殖的抑制作用,流式细胞仪分析细胞周期分布,Western印迹法检测cyclinDl,p21wafl/cipl蛋白的变化.结果 MTT示不同浓度姜黄素(7.5～120 μmol/L)在24～72 h范围内,浓度和时间依赖性抑制VSMC增殖;30 μmol/L以上浓度姜黄素显著抑制增殖的VSMC细胞周期进程,使S及G2/M期减少(P<0.05),G0/G1期增加(P<0.05);30 μmol/L的姜黄素可抑制cyclinDl表达,促进p21wafl/cipl蛋白表达.结论 姜黄素具有明确的抑制VSMC增殖和细胞周期停滞的作用,其与cyclinDl,p21wafl/cipl蛋白变化有关.     

依帕司他对醛糖还原酶和核转录因子-κB表达及血管平滑肌细胞增殖的影响

目的研究依帕司他对醛糖还原酶(AR)、核转录因子(NF)-κB表达及血管平滑肌细胞(VSMC)增殖的影响,探讨依帕司他抗细胞增殖的可能机制。方法取大鼠胸主动脉段行VSMC培养,用高浓度葡萄糖(22.5mmol/L)诱导AR基因表达,然后加入不同浓度的依帕司他,培养3d后行VSMC计数,并用免疫组化、RT-PCR及原位杂交的方法检测NF-κB及AR的表达。结果①随依帕司他浓度的增加,VSMC计数逐渐减少。②高浓度葡萄糖时NF-κB表达强阳性,加入不同浓度的依帕司他后,NF-κB表达逐渐减弱。③高浓度葡萄糖可明显诱导AR基因表达,依帕司他对其表达有抑制作用,且呈剂量依赖性。结论①高浓度葡萄糖可促进VSMC增殖,依帕司他可抑制这一增殖作用,且具有剂量依赖性。②依帕司他可抑制AR及NF-κB的表达。③依帕司他可能是通过抑制AR及NF-κB的表达继而抑制VSMC的增殖。     

胆固醇对血管平滑肌细胞增殖及迁移的作用

目的探讨胆固醇对血管平滑肌细胞增殖及迁移的作用。方法体外培养人血管平滑肌细胞株(VSMC),以12.5 mg/L、25.0 mg/L、50.0 mg/L不同浓度胆固醇(CH)分别作用细胞24 h、48 h、72 h后,MTT法检测VSMC的增殖情况;流式细胞术检测细胞进入S期的数量;EDU试剂盒检测CH作用后细胞的DNA合成;划痕实验检测VSMC迁移情况;Real-time PCR检测细胞中miR145的表达水平。结果 12.5 mg/L、25.0 mg/L、50.0 mg/L CH作用VSMC后可增加细胞活力,促进细胞增殖,与对照组比较,进入S期的VSMC细胞数量明显增多,细胞迁移增加(P0.05);与对照组比较,25.0 mg/L、50.0 mg/L CH可诱导VSMC DNA合成增加,并且明显降低miR-145的表达水平(P0.05)。结论 CH可诱导VSMC进入S期细胞增多,促进细胞增殖,并且增加细胞的DNA合成及细胞迁移,其机制可能与抑制miR-145的表达有关。     

恒磁场对血管紧张素Ⅱ预处理的人脐动脉血管平滑肌细胞增殖的影响

目的　观察恒磁场对离体人脐动脉血管平滑肌细胞 (VSMC)增殖的影响。方法　血管紧张素Ⅱ (AngⅡ )刺激人VSMC建立细胞增殖模型 ,置于 1mT和 5mT的恒磁场中培养 48h ,用四唑盐比色法和3H TdR参入法检测两组VSMC的增殖数量 ,流式细胞仪分析细胞周期。结果　恒磁场能逆转AngⅡ所致的人VSMC增殖数量增多 ,阻止VSMC由静止期 (G0 G1 期 )进入DNA合成期 (S期 )和有丝分裂期 (G2 M期 )。结论　平均磁感应强度为 1、5mT的恒磁场抑制VSMC增殖。     

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.