双歧杆菌对葡聚糖硫酸钠(DSS)诱导的小鼠结肠炎肠道黏膜的保护作用及其对NF-κB的影响

目的随着对炎症性肠病(inflammatory bowel disease,IBD)发病机制的深入研究,肠道微生态与免疫系统的密切关系日益受到重视。本研究旨在评价双歧杆菌单一活菌制剂对葡聚糖硫酸钠(dextran sulfate sodium,DSS)诱导的小鼠结肠炎肠道黏膜的保护作用及其可能作用机制。方法 BALB/c小鼠饮用含7%DSS的饮用水10d,诱导小鼠亚急性结肠炎的模型,模拟人类溃疡性结肠炎。空白对照组(n=6)饮用未添加DSS的饮用水。饮用DSS的小鼠(n=37)随机分为5组,分别给予不同的药物治疗:①提前给予双歧杆菌治疗组(Pre-BIF):在小鼠暴露于DSS前10d及暴露过程中给予双歧杆菌治疗;②强的松治疗组(PRED):在小鼠暴露于DSS同时给予强的松治疗;③双歧杆菌治疗组(BIF):小鼠暴露于DSS的同时给予双歧杆菌治疗;④强的松+双歧杆菌联合治疗组(PRED+BIF):小鼠暴露于DSS的同时给予强的松和双歧杆菌联合治疗;⑤生理盐水对照组(NS):小鼠暴露于DSS的同时给予生理盐水作为对照。不同药物皆以溶液形式灌胃给药。从4方面评价各组的处理反应:①一般情况:包括体重、结肠长度、大体评分;②组织病理评分;③化学比色法检测病变组织髓过氧化物酶(MPO)活性;④免疫组织化学方法检测活化的NF-κB。结果 Pre-BIF治疗组和BIF治疗组的大体评分、组织病理评分、MPO活性与NS对照组相比明显改善(P0.01;P0.05)。Pre-BIF治疗组、BIF治疗组和PRED+BIF治疗组的NF-κB活性评分显著低于NS对照组(P均0.01)。结论双歧杆菌对小鼠DSS结肠炎肠道黏膜具有保护作用,提前应用保护效果更好。双歧杆菌对肠道黏膜的保护作用与抑制NF-κB的活化有关。     

甘草酸二铵对大鼠结肠炎的抗炎作用机制研究

目的建立大鼠急性期结肠炎模型,观察甘草酸二铵(DG)对大鼠结肠炎的治疗作用,并探讨其抗炎机制。方法雌性SD大鼠分为实验组、模型组和正常对照组,每组10只。实验组、模型组大鼠用冰乙酸灌肠建立急性期结肠炎模型,实验组给予40 mg.kg-1.d-1DG干预治疗。观察疾病活动指数(DAI)、组织学变化及髓过氧化物酶(MPO)活性,免疫组化法检测核因子-κB(NF-κB)、肿瘤坏死因子-α(TNF-α)和细胞间粘附分子-1(ICAM-1)表达。结果实验组、模型组和正常对照组的DAI评分分别为3.5±0.6,7.1±0.8和0.5±0.4;组织学评分为3.5±0.9,6.1±1.0和1.0±0.5;MPO活性为0.72±0.08,2.02±0.10和0.22±0.04;TNF-α阳性率分别为(35.2±8.2)%,(62.5±10.1)%和(7.9±5.7)%;ICAM-1阳性率为(34.3±8.2)%,(60.2±8.3)%和(9.1±3.4)%;NF-κB阳性率为(23.3±9.2)%,(44.5±8.9)%和(9.6±4.4)%。与模型组相比,实验组的DAI、组织学及MPO活性显著改善,实验组的TNF-αI、CAM-1和NF-κB的表达显著降低,经one-way ANOVA及SNK-q检验,差异有统计学意义(P值均<0.01)。结论DG可显著改善大鼠结肠炎症,其机制可能是通过影响炎症反应的信号通路NF-κB活化及ICAM-1、TNF-α的产生和表达来抑制炎症反应。     

中药肠炎清治疗小鼠葡聚糖硫酸钠所致结肠炎的机制

目的:探讨肠炎清的疗效及其机制.方法:以葡聚糖硫酸钠(DSS)饮水法复制小鼠实验性结肠炎40只,随机平均分为4组:肠炎清中药组、柳氮磺胺吡啶(SASP)西药组、肠炎清和SASP中西药结合组和模型组.观察肠炎清(灌胃剂量为0.2mL/(20g?d)、1次/d、疗程7d)对疾病活动指数(DAI)和肠组织髓过氧化物酶(MPO)活性及TNF-α、IL-1β和IL-6mRNA表达的影响.结果:与模型组相比,肠炎清可降低DAI(1.413±0.835vs2.167±0.911,P<0.05)和MPO活性(72.4±0.590nkat/gvs117.0±0.902nkat/g,P<0.05),并降低肠组织TNF-α(0.841±0.190vs1.320±0.282,P<0.05)、IL-1β(0.641±0.095vs0.920±0.082,P<0.05)和IL-6mRNA(1.241±0.247vs1.620±0.312,P<0.05)的表达,中西医结合组以上指标下降更为明显(DAI:0.608±0.449;MPO:27.3±0.211;TNF-α:0.339±0.081;IL-1β:0.239±0.073;IL-6:0.639±0.141)(P<0.01).肠炎清与柳氮磺胺吡啶(SASP)的作用相当(P>0.05).结论:肠炎清可治疗DSS结肠炎,其降低肠组织TNF-α、IL-1β和IL-6mRNA的表达可能是其疗效机制之一.     

益生菌治疗的实验性结肠炎中调节性T细胞的作用

目的评价不同剂量益生菌对大鼠实验性结肠炎的疗效,研究治疗后全身及肠道局部调节性T细胞(Tr)的变化情况,探讨益生菌作用机制。方法建立三硝基苯磺酸(TNBS)实验性结肠炎大鼠模型。所用益生菌为双歧三联活菌(商品名:培菲康)。设阴性对照组、泼尼松组、柳氮磺胺吡啶 (SASP)组、益生菌小、大剂量组(剂量分别为150和300 mg·kg-1·d-1)、益生菌+泼尼松或SASP(益生菌剂量为150 mg·kg-1·d-1)组。治疗2周后组织学积分评定疗效;流式细胞仪检测各组外周血、脾脏和结肠上皮内CD4+CD25+及CD8+CD28-两种Tr比例变化。采用t检验行统计学分析。结果组织学评分显示大剂量益生菌对实验性结肠炎有效(2．2±0．8比3．5±0．7,P<0．05),而小剂量益生菌单独作用无明显疗效,联合泼尼松或SASP治疗比单独应用疗效更强;大剂量益生菌治疗后CD4+ CD25+Tr比例在外周血(3．4±0．6比11．7±4．7,P<0．05)及脾脏(2．1±1.9比10．3±3．1,P<0．05) 中下降,在结肠内上升(36．6±15．0比7．9±4．7,P<0．05);CD8+CD28-Tr则相反,在外周血及脾脏中上升(91．7±4．5比59．0±4．2,97．3±0．1比88．2±6．9,P<0．05),在结肠内下降(42．2±6．0比68．5 ±8．6,P<0．05)。Tr的这种变化与泼尼松或SASP治疗存在一定差异。结论益生菌单独大剂量或小剂量联合泼尼松或SASP治疗TNBS诱导的结肠炎有效,CD4+CD25+和CD8+CD28-Tr在发挥疗效过程中可能起一定作用。     

益生菌VSL#3对大鼠实验性结肠炎大肠组织TLR4及NF-κBp65表达的影响

目的探讨大鼠实验性结肠炎TLR4/NF-κBp65信号转导通路及VSL#3的干预作用。方法 5%葡聚糖硫酸钠(DSS)溶液自由饮用1周构建大鼠急性实验性结肠炎模型,观察和评价大肠黏膜的组织学损伤,计算DAI评分及大鼠病理学评分。应用Real-time PCR方法检测大肠组织TLR4及NF-κBp65 mRNA的表达;Western blotting方法检测大肠组织TLR4及NF-κBp65表达水平。结果益生菌VSL#3组大鼠一般情况明显好于模型组。DAI评分:益生菌VSL#3组DAI评分较模型组低(P0.05),益生菌VSL#3组病理学评分较模型组低(P0.05);Real-time PCR及Western blotting检测TLR4及NF-κBp65的表达水平:与模型组相比,益生菌VSL#3组TLR4表达水平明显下降(P0.05);模型组NF-κBp65的表达明显高于益生菌VSL#3组及正常对照组(P0.05)。结论益生菌VSL#3通过调节TLR4/NF-κBp65信号转导通路减轻大鼠实验性结肠炎。     

慢性应激对小鼠溃疡性结肠炎的影响

目的观察慢性束缚应激对葡聚糖酸钠(DSS)诱导的小鼠溃疡性结肠炎(UC)的影响。方法64只BALB/C小鼠分为6组,单纯应激组、正常对照组各16只,应激 2DSS组、应激 4DSS组、2DSS组、4DSS组各8只。采用自制的束缚笼对应激组小鼠建立慢性心理应激动物模型。采用小鼠自由饮用DSS溶液的方法建立UC模型。每日观察各组疾病活动指数(DAI)。并在实验结束后测量结肠组织损伤评分(HS)、髓过氧化物酶(MPO)活性。HS评分通过在光镜下观察结肠组织学改变得出。并用分光光度法测定结肠组织中MPO的活性。结果单纯应激组小鼠体重增长较正常对照组缓慢(P<0.05)。4DSS组小鼠DAI评分、HS评分及结肠组织MPO活性均较正常对照组增高(P<0.05)。应激 4DSS组上述指标较正常对照组变化更显著,与4DSS组比较亦增高(P<0.05)。2DSS组上述指标与正常对照组相比无明显区别(P>0.05)。应激 2DSS组上述指标较正常对照组增高(P<0.05)。结论慢性束缚应激可以使小鼠发生UC的易感性增加并加重DSS结肠炎的病理损伤。     

烟碱型乙酰胆碱受体α7激动剂减轻实验性结肠炎炎性反应

目的 探讨烟碱型乙酰胆碱受体α7(nAChRα7)激动剂对三硝基苯磺酸(TNBS)诱导结肠炎的治疗作用.方法 将BALB/C小鼠随机分为对照组(C)、TNBS结肠炎组(T)和nAChRα7激动剂八角枫碱(AN)或拮抗剂二碘四氯吲哚胺(CHD)治疗组.实验第1天诱导(TNBS)结肠炎,实验开始后即对每只小鼠予AN 10μg或CHD 1.5 μg腹腔注射,隔日重复直到实验结束.实验第8天处死小鼠,分别检测肠组织髓过氧化物酶(MPO)活性,酶联免疫吸附试验检测肿瘤坏死因子(TNF)-α浓度,分离结肠黏膜固有层单个核细胞(LPMC),提取核蛋白,Western印迹法检测核因子(NF)-κB P65的表达.结果 AN治疗组结肠组织损伤程度、MPO活性、组织TNF浓度等均明显低于TNBS组[MPO活性为(7.6±2.1)U/mg比(12.2±2.6)U/mg,组织TNF浓度为(396±98)pg/g比(627±112)Pg/g],LPMC NF-κB的活化明显受抑制;CHD治疗组结肠组织损伤程度、MPO活性[(14.1±1.8)U/mg]、组织TNF浓度[(692±79)Pg/g]均明显高于其他结肠炎组,LPMC NF-κB明显活化.结论 nAChR α7激动剂AN能明显抑制实验性结肠炎肠道炎性反应.     

双歧杆菌影响溃疡性结肠炎患者肠黏膜的研究

目的　研究双歧杆菌对溃疡性结肠炎 (UC)患者肠黏膜内核因子κB (NF κB)的表达和激活的影响及肿瘤坏死因子 (TNF) α、白细胞介素 (IL) 1β、IL 10mRNA表达的影响。 方法　 30例UC患者经治疗后 ,应用Western蛋白印迹分析检测NF κBp6 5表达情况 ;用凝胶电泳迁移率改变分析检测NF κB与DNA结合活性 ;逆转录 PCR检测肠黏膜内细胞因子的表达。结果　应用双歧杆菌后 3例复发 ,对照组 14例复发 ,与对照组相比 ,NF κB与DNA结合活性明显降低 ,蛋白表达量明显下降 (治疗前 0 82± 0 0 5 ,治疗后 0 31± 0 0 5 ,P <0 0 1) ;双歧杆菌明显抑制了TNF α、IL 1β的表达 ;提高IL 10的表达。结论　双歧杆菌的作用可能与抑制NF κB的激活、降低TNF α、IL 1β等致炎因子的表达 ,提高IL 10等抑炎因子的表达有关     

双歧杆菌对小鼠急性实验性结肠炎作用的研究

目的 研究双歧杆菌在葡聚糖硫酸钠(DSS)诱导的急性溃疡性结肠炎小鼠模型中的作用.方法 将80只BALB/C小鼠均分为8组,每组10只.除正常对照组、单纯0501菌株组、单纯c122菌株组外,其他5组动物均给予5%DSS造模7 d.在造模开始前2 d,阴性对照组用0.9%氯化钠液灌肠、阳性对照组用柳氮磺胺吡啶(SASP)20 mg/ml灌肠、DSS+0501菌株组用1×109 CFU/ml 0501菌液灌肠、DSS+c122菌株组用1×109 CFU/ml c122液菌灌肠.9 d后处死动物取结肠标本,行H-E染色,观察镜下结肠病理变化,并用免疫组化染色、RT-PCR技术分析结肠黏膜中白细胞介素(IL)-10 mRNA及蛋白表达.结果 DSS造模过程中给予双歧杆菌灌肠小鼠(0501菌株组和c122菌株组)的结肠炎性反应程度较模型组加重,结肠黏膜IL-10表达减少.而单纯给予双歧杆菌灌肠小鼠(单纯0501菌株组和单纯c122菌株组)未见结肠炎表现.结论 双歧杆菌的某些菌株在结肠黏膜屏障功能受损情况下,可加重溃疡性结肠炎小鼠的结肠黏膜损伤.     

双歧杆菌三联活菌对DSS诱导结肠炎鼠肠紧密连接蛋白JAM-1的影响

目的:探讨双歧杆菌三联活菌对葡聚糖硫酸钠(dextran sulfate sodium,DSS)诱导的结肠炎小鼠肠道炎症及紧密连接蛋白连接黏附分子1(junctional adhesion molecule-1,JAM-1)表达与分布的影响.方法:将SPF级♀Balb/c小鼠(8-10周龄)随机分为5组:正常对照NC组、益生菌BB组(正常小鼠予益生菌灌胃14 d)、急性DSS模型组(生理盐水灌胃14 d+第8天起4%DSS溶液自由饮用7 d)、BD组(益生菌灌胃7 d+第8天起4%D S S溶液自由饮用7 d)、B D B组(益生菌灌胃14 d+第8天起4%D S S溶液自由饮用7 d).记录小鼠每日体质量变化.第15天处死小鼠、分离结肠,观察各组肠道损伤情况,以组织病理学积分评估结肠炎的严重程度.采用Western blot法、免疫组织化学法(IHC)检测结肠组织中JAM-1的表达及分布.结果:与D S S模型组相比,益生菌干预组(BD、BDB组)小鼠减轻的体质量得到不同程度恢复(95.17%±3.34%、87.17%±1.83%vs 81.49%±2.16%,P10.01,P2=0.08),病变结肠缩短程度、肠黏膜水肿,上皮细胞破坏程度及肠道炎症细胞浸润减轻,且BD组小鼠的改善程度优于BDB组.Western blot结果显示给予益生菌干预,BD、B D B组肠黏膜组织JAM-1蛋白的表达水平较DSS组显著增加(0.725±0.027、0.739±0.033 vs 0.454±0.073,均P0.05).免疫组织化学结果显示DSS模型组小鼠结肠黏膜JAM-1染色强度明显减弱,染色细胞数减少,分布散乱、中断,益生菌处理后JAM-1染色强度及阳性细胞数减少程度显著改善.仅给予益生菌灌胃的小鼠,体质量、结肠大体、镜下表现以及结肠组织中JAM-1蛋白表达水平及分布,与正常小鼠无显著差异(P0.05).结论:双歧杆菌三联活菌可能通过影响JAM-1蛋白的表达与分布,改善肠黏膜的屏障功能,从而减轻小鼠急性期肠道炎症反应.     

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.