糖基化终产物对小鼠巨噬细胞基质金属蛋白酶诱导物表达、分泌及基质金属蛋白酶9活性的影响

目的 探讨糖基化终产物对小鼠巨噬细胞基质金属蛋白酶诱导物表达、分泌及基质金属蛋白酶9活性的影响.方法在培养的小鼠巨噬细胞株(J774A.1)中分别加入不同浓度(50、100、200及400 mg/L)的糖基化终产物干预24 h和同一浓度(200 mg/L)的糖基化终产物干预12、24及48 h,以无血清培养基和相应浓度的牛血清白蛋白为对照.用逆转录聚合酶链方法检测基质金属蛋白酶诱导物mRNA的表达,用酶联免疫吸附法检测上清中基质金属蛋白酶诱导物蛋白水平,用酶谱法检测上清中基质金属蛋白酶9的活性.结果 糖基化终产物干预组的基质金属蛋白酶诱导物mRNA表达水平和上清中蛋白水平与对照组比较差异有显著性,且随时间和浓度增加而增加(P<0.05).糖基化终产物干预组的上清中基质金属蛋白酶9的活性与对照组比较差异有显著性,且随时间和浓度增加而增加(P<0.05).结论 糖基化终产物促进小鼠巨噬细胞基质金属蛋白酶诱导物mRNA表达、蛋白分泌及基质金属蛋白酶9的活性;提示糖基化终产物可能通过调节巨噬细胞基质金属蛋白酶诱导物表达、分泌及基质金属蛋白酶9的活性而影响糖尿病动脉粥样硬化斑块的稳定性.     

血管紧张素Ⅱ对载脂蛋白E敲除小鼠主动脉粥样硬化斑块细胞外基质金属蛋白酶诱导因子表达影响

目的探讨血管紧张素Ⅱ对载脂蛋白E敲除小鼠主动脉粥样硬化斑块细胞外基质金属蛋白酶诱导因子表达的影响。方法载脂蛋白E基因敲除小鼠经高脂饮食饲养建立动脉粥样硬化模型,用血管紧张素Ⅱ干预。用免疫组织化学法观察粥样硬化斑块内细胞外基质金属蛋白酶诱导因子表达,用RT-PCR及Western blotting检测主动脉内细胞外基质金属蛋白酶诱导因子表达。结果血管紧张素Ⅱ干预组细胞外基质金属蛋白酶诱导因子在动脉粥样硬化斑块内阳性表达较对照组明显增加;血管紧张素Ⅱ干预组主动脉内细胞外基质金属蛋白酶诱导因子mRNA及蛋白表达较对照组明显增加。结论血管紧张素Ⅱ能诱导主动脉粥样硬化斑块内细胞外基质金属蛋白酶诱导因子的表达。     

脉心康对载脂蛋白E基因敲除小鼠主动脉核因子κB和基质金属蛋白酶9表达的调控

目的观察脉心康对载脂蛋白E基因敲除小鼠主动脉核因子κB、基质金属蛋白酶9mRNA表达水平的调控作用。方法6周龄载脂蛋白E基因敲除小鼠,随机分为高脂血症组(模型组)、洛伐他汀组及脉心康组,相同遗传背景的同龄正常C57BL6J小鼠为正常对照组。原位杂交观察各组主动脉核因子κB和基质金属蛋白酶9mRNA表达的强度。结果各给药组与模型组比较,核因子κBmRNA、基质金属蛋白酶9mRNA阳性细胞表达率均明显降低(P<0.01)。光镜下发现正常对照组主动脉壁内皮细胞、平滑肌细胞胞质内核因子κBmRNA、基质金属蛋白酶9mRNA阳性表达细胞极少见;模型组主动脉壁内皮细胞、平滑肌细胞胞质内阳性表达的棕褐色颗粒较多见,且棕褐色颗粒染色均较深;脉心康组主动脉壁可见内皮细胞、平滑肌细胞胞质内阳性表达的棕褐色颗粒,但远较模型组少,棕褐色颗粒染色深浅较均匀。结论脉心康可降低载脂蛋白E基因敲除小鼠主动脉核因子κB、基质金属蛋白酶9mRNA表达,发挥抗动脉粥样硬化、稳定斑块的作用。     

南蛇藤素对载脂蛋白E基因敲除小鼠斑块内胶原、巨噬细胞移动抑制因子和基质金属蛋白酶9表达的影响

目的观察南蛇藤素对载脂蛋白E基因敲除小鼠斑块中胶原、巨噬细胞移动抑制因子和基质金属蛋白酶9表达的影响。方法8周龄雄性载脂蛋白基因敲除小鼠12只,随机分为南蛇藤素干预组和动脉粥样硬化模型组,每组各6只,同龄的雄性C57BL/6J小鼠6只作为正常对照,各组均给以高脂饮食饲养8周,在高脂饲养的后4周,分别予以南蛇藤素和相当剂量的溶剂二甲基亚砜腹腔注射,每日1次,连续用药4周;处死后行主动脉连续石蜡切片、HE染色观察组织形态学改变,苦味酸-天狼星红染色检测斑块内胶原含量,免疫组织化学方法观察主动脉斑块内巨噬细胞移动抑制因子和基质金属蛋白酶9蛋白表达的强度。结果模型组形成了早期斑块,南蛇藤素组斑块面积较模型组明显减小,分别为4270.74±1027.64μm2和8971.19±1665.76μm2(P<0.01),南蛇藤素组斑块内胶原含量显著高于模型组(平均光密度分别为0.0275±0.0068和0.0142±0.0054,P<0.01);南蛇藤素组与模型组比较斑块内基质金属蛋白酶9表达明显降低(平均光密度分别为0.0054±0.0020和0.0263±0.0080,P<0.001),巨噬细胞移动抑制因子的表达也明显降低(平均光密度分别为0.0114±0.0016和0.0227±0.0039,P<0.001)。结论南蛇藤素可能通过下调载脂蛋白E基因敲除小鼠斑块内基质金属蛋白酶9和巨噬细胞移动抑制因子表达,抑制胶原的降解进而发挥抗动脉粥样硬化及稳定斑块作用。     

阻断CD40-CD40配体系统对动脉粥样硬化的影响

目的探讨阻断CD40-CD40配体系统对动脉粥样硬化的影响。方法18只载脂蛋白E基因敲除小鼠随机分为阳性对照组(n=10)和抗CD40配体抗体组(n=8),并以近交系C57BL/6小鼠作为正常对照。测定血脂、可溶性血管细胞粘附分子1和可溶性细胞间粘附分子1浓度。观察主动脉组织病理形态学改变,免疫组织化学法测定斑块部位巨噬细胞、平滑肌细胞和CD4 T细胞百分率。Western杂交分析测定基质金属蛋白酶9的蛋白表达。结果抗CD40配体抗体治疗可明显降低可溶性血管细胞粘附分子1和可溶性细胞间粘附分子1浓度(P<0.01),对血脂无明显影响(P>0.05);可减轻动脉粥样硬化病变,减少斑块部位巨噬细胞和CD4 T细胞,增加平滑肌细胞数量(P<0.05),降低基质金属蛋白酶9的表达(P<0.01)。结论阻断CD40-CD40配体系统可使血清可溶性粘附分子浓度下降,抑制炎症反应,从而减轻动脉粥样硬化病变,对血脂无影响。     

前列腺素E1对兔动脉粥样硬化易损斑块的影响

目的研究前列腺素E1对兔动脉粥样硬化易损斑块的影响及机制。方法 22只新西兰大白兔高脂饲料(1%胆固醇)喂养2周后,进行腹主动脉球囊损伤术,术后继续高脂喂养,7周后,随机分为模型组、前列腺素E1组和辛伐他汀组,同时改为普通饲料继续喂养4周,13周末,所有兔给予中国斑点蝰蛇毒和组胺进行药物诱发。观察药物干预后血脂、斑块形态、斑块组分及炎症因子的变化。结果前列腺素E1对血脂没有影响;与模型组比较,前列腺素E1组能显著增加斑块的纤维帽厚度(101.72±34.89μm比79.86±16.98μm,P<0.01),减小斑块易损指数(0.94±0.27比3.83±1.45,P<0.01);并且能够显著抑制斑块中巨噬细胞的累积(P<0.01)及其分泌的炎症因子基质金属蛋白酶1和基质金属蛋白酶9的表达(P<0.01),前列腺素E1组与辛伐他汀组比较差异无显著性。结论前列腺素E1能够稳定兔动脉粥样硬化易损斑块,该作用与脂质代谢无关,但与抑制斑块中巨噬细胞的累积及其分泌炎症因子密切相关。     

高棕榈酸饮食对ApoE基因敲除小鼠动脉粥样硬化的影响

1目的：观察高棕榈酸饮食对载脂蛋白E（ApoE）基因敲除小鼠的血脂、血浆游离脂肪酸水平、动脉粥样硬化斑块面积、斑块中胶原含量和基质金属蛋白酶2表达的影响。方法：将20只6～8周龄雄性ApoE基因敲除小鼠随机分为对照组和高棕榈酸饮食组,每组10只。分别给予普通小鼠饲料和含5％棕榈酸的饮食,连续喂养12周。用比色法检测血脂和血浆游离脂肪酸水平;主动脉根部连续石蜡切片,Masson染色检测斑块内胶原含量,免疫组化法检测主动脉基质金属蛋白酶2的表达。结果：两组血脂水平无明显差异。与对照组相比,高棕榈酸饮食组血浆游离脂肪酸水平显著升高,主动脉斑块内胶原含量显著降低,主动脉基质金属蛋白酶2表达明显增加（P均〈0．05）。结论：高棕榈酸饮食能够升高血浆游离脂肪酸水平,降低斑块内胶原含量,从而降低动脉粥样硬化斑块稳定性,其机制可能与其上调基质金属蛋白酶2的表达有关。     

糖基化终产物对凝集素样氧化型低密度脂蛋白受体1表达的影响

目的 研究长期高血糖所致糖基化终产物对巨噬细胞凝集素样氧化型低密度脂蛋白受体1表达的影响.方法 U937细胞经佛波酯诱导分化,并将不同浓度或同一浓度糖基化终产物与诱导分化48 h后的U937细胞共同孵育,用Western Blotting法检测凝集素样氧化型低密度脂蛋白受体1蛋白的表达.同时应用ELISA法测定24例2型糖尿病患者及22例正常对照者血清可溶性氧化型低密度脂蛋白受体1的含量.结果 100、200和400 mg/L 糖基化终产物刺激后细胞表面凝集素样氧化型低密度脂蛋白受体1蛋白表达量分别是对照组的1.85、3.22和4.65倍(P<0.05);400 mg/L的糖基化终产物作用12、24、48 h后,U937巨噬细胞该受体蛋白表达量分别为0 h的2.85、3.89和4.3倍(P<0.05).糖尿病患者血清氧化型低密度脂蛋白受体1及糖基化终产物含量较正常对照者显著升高(P<0.01),两者呈正相关(P<0.001). 结论糖基化终产物可增加U937巨噬细胞凝集素样氧化型低密度脂蛋白受体1蛋白表达且呈浓度和时间依赖性.这可能与糖尿病患者加速泡沫细胞形成而易致动脉粥样硬化有关.     

载脂蛋白E基因敲除小鼠动脉粥样硬化斑块中血小板因子4和Toll样受体2的表达

目的观察高脂饲养的载脂蛋白E基因敲除小鼠动脉粥样硬化斑块表达Toll样受体2和血小板因子4的情况,探讨血小板因子4对内皮细胞Toll样受体2表达的影响。方法高脂饲料喂养载脂蛋白E基因敲除小鼠12周,建立动脉粥样硬化模型。安乐死处死动物,原位灌流固定,取主动脉于10%中性缓冲福尔马林中固定,石蜡包埋连续切片,HE染色观察动脉粥样硬化斑块形态,免疫组织化学检测斑块中Toll样受体2和血小板因子4的表达。结果载脂蛋白E基因敲除小鼠血脂水平明显增高,主动脉HE染色可见态动脉粥样硬化病变。在载脂蛋白E基因敲除小鼠主动脉富含脂质斑块中Toll样受体2表达上调,其中血管内皮细胞、巨噬细胞表达Toll样受体2明显增多。载脂蛋白E基因敲除小鼠主动脉斑块中也发现有血小板因子4表达,主要在内皮细胞和动脉粥样硬化斑块肩部。结论1.载脂蛋白E基因敲除小鼠粥样斑块中Toll样受体2表达上调,并且Toll样受体2主要表达在粥样斑块的内皮细胞和巨噬细胞上。2.载脂蛋白E基因敲除小鼠动脉粥样硬化斑块中可见血小板因子4表达。     

糖尿病患者动脉粥样硬化斑块内基质金属蛋白酶2和9与斑块稳定的关系

目的　比较糖尿病患者与非糖尿病组患者动脉粥样硬化斑块内基质金属蛋白酶 2和基质金属蛋白酶 9表达的差异 ,初步探索基质金属蛋白酶 2和基质金属蛋白酶 9与糖尿病动脉粥样硬化斑块稳定的关系。方法　从2 3例糖尿病足截肢和 17例尸检下肢动脉标本中选取晚期动脉粥样硬化病变的组织块共 12 6块 ,分为糖尿病组 (74块 )和非糖尿病组 (5 2块 ) ,从中随机选取各 4 0个组织块 ,运用免疫组织化学染色法检测基质金属蛋白酶 2和 9在两组粥样硬化斑块中的表达。结果　糖尿病组抗基质金属蛋白酶 2、抗基质金属蛋白酶 9免疫沉积物主要集中在斑块核心周围 ,特别是在斑块的肩部和纤维帽。糖尿病组动脉斑块内抗基质金属蛋白酶 2免疫沉积物表达显著高于非糖尿病组 (免疫沉淀物积分光密度值分别为 6 90 14± 14 4 5 9和 5 70 0 4± 16 171,阳性面积百分比分别为 13.0 %± 2 .7%和 11.1%± 3.3% ) ;糖尿病组斑块内基质金属蛋白酶 9表达也显著高于非糖尿病组 (免疫沉淀物积分光密度值分别为 10 2 4 85± 2 0 4 31和 75 2 80± 1310 6 ,阳性面积百分比分别为 18.4 %± 3.6 %和 13.7%± 2 .3% )。结论　基质金属蛋白酶 2和 9在糖尿病组动脉粥样硬化斑块中的表达显著高于非糖尿病组。基质金属蛋白酶 2和 9在糖尿病动脉中表达增     

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.