血管内皮细胞生长因子与治疗性血管新生

本文概述了血管内皮细胞生长因子(VEGF)家族及其受体的组成,介绍了调控VEGF表达的因素及VEGF信号传导途径。着重阐述了VEGF促血管新生的作用机制,以及VEGF在治疗性血管新生中的研究与应用现状、存在问题及未来发展前景。还简要介绍了VEGF其他的生物学作用。     

血管内皮生长因子与缺血性脑卒中的研究进展

<正>脑卒中包括缺血性脑卒中和出血性脑卒中,血管内皮生长因子(vascular endothelial growth factor,VEGF)是缺血性脑卒中的研究热点和潜在靶点。近年来发现,VEGF在缺血性脑卒中起重要作用。我们将探讨脑缺血诱导VEGF及其在缺血性脑卒中的病理生理作用,以及VEGF在缺血性脑卒中治疗方面的研究进展。1 VEGF概况VEGF是在血管发生和血管生成中扮演不同角色的强效生长因子。VEGF在肿瘤微血管通透性中作为促渗透因     

胎盘生长因子与心血管疾病中的血管生成

胎盘生长因子（P lGF）是血管内皮生长因子（VEGF）家族成员之一,与VEGF结构相似,参与病理状态下的新生血管和侧支血管的形成,而对生理状态下的血管发育影响很小,可望用于治疗缺血性心脏病。作者就其结构及促血管生成的作用作一综述。     

血管内皮细胞生长因子与缺血性脑损伤

血管内皮细胞生长因子 (VEGF)是近年来发现的一种特异性的促血管内皮细胞生长、增加血管通透性的生长因子。VEGF及其受体在脑缺血后表达明显增加 ,并可能对缺血性脑损伤发挥双重作用。有关VEGF的生物学特征、VEGF受体及信号转导机制、脑缺血后表达与调节及VEGF在缺血性脑血管病中的作用等研究取得了新的进展 ,并展现了临床应用前景。     

血管内皮生长因子与缺血性脑血管病

血管内皮生长因子(VEGF)可诱导内皮细胞有丝分裂和体内新生血管形成，引起血管通透性增加，在胚胎发育、肿瘤的生长和转移、缺血性心脑血管疾病的发病和防治中具有重要意义。文章对VEGF的生物学作用以及VEGF与缺血性脑血管病的关系进行了综述。     

血管内皮生长因子与缺血性脑血管病

血管内皮生长因子(VEGF)可诱导内皮细胞有丝分裂和体内新生血管形成,引起血管通透性 增加,在胚胎发育、肿瘤的生长和转移、缺血性心脑血管疾病的发病和防治中具有重要意义。文章对 VEGF的生物学作用以及VEGF与缺血性脑血管病的关系进行了综述。     

治疗性血管新生在心肌梗死后的应用进展

心肌梗死(MI)是一种急性缺血性心脏病，其病理特点是各种原因引起的心肌血管狭窄和堵塞，可并发心律失常、休克和心力衰竭，严重时危及患者生命。因此，促血管新生成为治疗MI的有效方法之一。近年来，随着对血管生长因子和血管新生研究的不断深入，治疗性血管新生已成为MI后治疗研究的新领域，在恢复血运重建方面起到重要作用。治疗性血管新生的方法主要包括蛋白质治疗、基因治疗和细胞治疗。本文就治疗性血管新生在MI后的应用做一综述。     

血管内皮生长因子在碱烧伤角膜新生血管中表达的研究

目的 观察血管内皮生长因子（VEGF）在角膜新生血管中的表达，探讨其在角膜新生血管形成过程中的作用。方法 碱烧伤法制作大鼠角膜新生血管模型，采用免疫组化及RT-PCR法分别检测促血管内皮生长因子VEGF蛋白和VEGF mRNA的表达。结果 碱烧伤4d后，实验组大鼠角膜新生血管生成。活化的VEGF的表达在新生血管的形成过程中有一动态变化，即伤后早期显著增加，4d时最高，7d后开始回落。结论 炎症性角膜新生血管形成早期过程中，多种促血管生成因子如VEGF显著活化，在角膜新生血管的形成过程中起着重要作用。     

VEGF对冠心病血管新生的影响

本文以血管内皮细胞生长因子（VEGF）及其受体在血管新生中的生物学效应为基础,围绕着血管新生在缺血性心脏病中的作用,讨论了VEGF对动脉粥样硬化血管新生的影响,分析了VEGF生物作用多样性可能与浓度相关性调整有关。     

促血管新生研究进展

血管新生疗法是重症缺血性心脏病和闭塞性动脉硬化症的新治疗措施 ,从应用血管生长因子和其基因导入到血管内皮祖细胞移植 ,有关血管新生的概念发生了很大变化。本文回顾了血管内皮生长因子基因治疗的基础及临床研究 ,对血管内皮祖细胞在血管新生疗法中的应用进行了展望。自体骨髓细胞有可能成为血管新生疗法中的新型材料     

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.