结缔组织生长因子在糖尿病肾病中的作用研究进展

结缔组织生长因子具有促进细胞增殖分化、血管生成、基质合成积聚等作用,在糖尿病肾病导致肾小球硬化和肾小管间质纤维化的过程中起关键性作用.通过干预结缔组织生长因子可以缓解糖尿病肾病肾脏纤维化的进展.本文对结缔组织生长因子在糖尿病肾病发生发展中的作用进行综述.     

糖尿病肾病发病机制中若干相关生长因子

糖尿病肾病是糖尿病最常见的并发症，也是糖尿病患者的主要死亡原因。多种生长因子在参与糖尿病肾病的发病机制中是通过不同途径、不同机制发挥重要作用。目前，关于生长因子对糖尿病肾病进展的研究大多是在体外培养和动物实验中进行，本文就几个主要相关生长因子的作用机制及研究进展作一综述。     

足细胞和糖尿病及其肾病

肾小球足细胞损伤和丢失是肾小球硬化形成和发展的关键因素。糖尿病时足细胞可出现密度和数量减少、足突增宽、足细胞脱落等改变,且可从尿中丢失,继而导致糖尿病肾病的发生。高血糖、高血压、氧化应激及一氧化氮等可直接损伤足细胞,并抑制α3β1整合素、nephrin的表达,促进血管内皮生长因子、Ⅳ型胶原、糖基化终末产物受体、转化生长因子β等的表达而加重足细胞损伤。因而,探索足细胞损伤在糖尿病肾病发生、发展中的病理发展过程对糖尿病肾病的防治具有重要意义。     

葡萄糖转运蛋白及其在糖尿病肾病中的作用

糖尿病肾病是糖尿病的主要慢性并发症。糖代谢紊乱在其发病机制中起着重要的作用 ,葡萄糖转运蛋白是调节葡萄糖进入系膜细胞的主要载体 ,其可能通过糖代谢途径 ,蛋白激酶C(PKC)途径 ,转化生长因子 (TGF) β1等细胞因子及基因背景等多因素途径参与糖尿病肾病的发生发展。     

葡萄糖转运蛋白及其在糖尿病肾病中的作用

糖尿病肾病是糖尿病的主要慢性并发症。糖代谢紊乱在其发病机制中起着重要的作用，葡萄糖转运蛋白是调节葡萄糖进入系膜细胞的主要载体，其可能通过糖代谢途径，蛋白激酶C（PKC）途径，转化生长因子（TGF）β1等细胞因子及基因背景等多因素途径参与糖尿病肾病的发生发展。     

细胞因子、细胞生长因子与糖尿病微血管病变

分别论述了肿瘤坏死因子、白介素－１β、血小板源生长因子、成纤维细胞生长因子、转化生长因子－β、胰岛素样生长因子－１、白介素－６在糖尿病肾病及糖尿病视网膜病变发生与发展中的作用。     

糖尿病肾病的肾小管损伤研究进展

肾小管损伤是糖尿病肾脏病变的一个重要方面,包括肾小管上皮细胞肥大、凋亡,肾小管基底膜增厚,细胞外基质堆积,肾小管间质纤维化等,其中高血糖、氧化应激、蛋白质非酶糖化的影响以及血管紧张素Ⅱ、转化生长因子(TGF)-β、结缔组织生长因子(CTGF)、胶原酶及一些炎性趋化因子在基因转录、翻译、介导生物学作用等各个过程的相互作用共同促进了糖尿病肾小管病变的发生、发展.肾小管病变及肾小管问质纤维化在糖尿病肾病中的重要性逐渐被认识,对其机制的研究可以为临床治疗糖尿病.肾病提供指导.     

结缔组织生长因子与糖尿病肾病

本文从细胞培养、动物模型、活检标本等方面介绍了结缔组织生长因子(CTGF)在糖尿病中以转化生长因子-β(TGF-β)依赖和独立的方式,通过引起成纤维细胞增殖和细胞外基质蛋白的合成,介导了糖尿病肾病的发生、发展,并对其可能的发病机制进行了初步探讨.揭示CTGF是引起糖尿病患者血糖升高等一些生化因素和TGF-β等细胞因子共同作用下,导致肾脏纤维化的重要中介,从而为糖尿病肾病的诊治提供新的思路.     

细胞因子,细胞生长因子与糖尿病微血管病变

分别论述了肿瘤坏死因子、白介素－１β、血小板源生长因子、成纤维细胞生长因子，转化生长因子－β、胰岛素样生长因子－１、白介素－６在糖尿病肾病及糖尿病视网膜病发生与发展中的作用。     

血管内皮生长因子基因3'-非翻译区C936T多态性与2型糖尿病肾病相关

采用PCR-RFLP方法分析了194例2型糖尿病患者血管内皮生长因子(VECF)基因3'-非翻译区C936T变异与糖尿病肾病的关系.发现糖尿病肾病组C等位基因及CC基因型频率显著高于非肾病组和正常对照组,提示C等位基因及CC基因型患者可能是糖尿病易于发生肾病危险性的遗传标志.     

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.