氧化应激与支气管哮喘气道黏液高分泌研究进展

哮喘是一种以支气管收缩可逆性、肺部炎症及气道重塑为特点的慢性气道炎症性疾病.黏液过度分泌导致气道阻塞、肺功能下降、气道重塑和感染增加.过度的活性氧/活性氮(ROS/RNS)产生造成气道炎症,气道高反应性,气道微血管高通透性和气道黏液高分泌,以及组织损伤和形态的改变.减轻氧化应激或增加抗氧化能够减轻气道嗜酸粒细胞,减少黏液分泌,减轻支气管高反应性.本文就氧化应激与哮喘气道黏液高分泌的关系作一综述.     

白细胞介素25在支气管哮喘中的作用

正支气管哮喘(简称哮喘)是严重危害人类健康的慢性气道炎症性疾病~([1]),哮喘的主要特征包括慢性嗜酸性粒细胞性气道炎症、气道高反应性、气道重塑和黏液过度分泌~([2])。近年来,我国哮喘的发病率逐年上升,带来巨大的社会和经济负担。尽管国内外已有大量关于支气管哮喘发病机制的临床和动物研究,但哮喘气道慢性炎症和气道重塑的机制仍尚未完全阐明~([3])。Th1/Th2免疫调节失衡是哮喘的主要发病机制之一,Th2细胞被认为是嗜酸性粒细胞     

哮喘气道重塑及其药物干预治疗

支气管哮喘是气道的慢性炎症性疾病。近年来研究发现．除气道炎症外，哮喘的另一重要特征是气道壁的结构改变——气道重塑。目前认为气道重塑是导致气道不可逆性阻塞和气道高反应性的主要病理基础。气道重塑的组织学特征包括气道壁增厚．上皮下纤维化，平滑肌细胞增生、肥大．杯状细胞和黏液腺增生、肥大。血管生成。现多认为气道重塑是在炎症基础上     

Toll样受体4与支气管哮喘气道高反应

气道高反应性是支气管哮喘的基本特征.气道高反应的机制目前尚未完全阐明.当前支气管哮喘的治疗亦不能有效地抑制气道高反应性和气道重塑.近来发现,Toll样受体是一种属于Ⅰ型跨膜蛋白的天然免疫模式识别受体.TLR4通过调控气道炎症,促进气道平滑肌增生,参与气道重塑等方式参与气道高反应性过程.本文主要探讨TLR4与在支气管哮喘...     

Toll样受体4与支气管哮喘气道高反应

气道高反应性是支气管哮喘的基本特征.气道高反应的机制目前尚未完全阐明.当前支气管哮喘的治疗亦不能有效地抑制气道高反应性和气道重塑.近来发现,Toll样受体是一种属于I型跨膜蛋白的天然免疫模式识别受体.TLR4通过调控气道炎症,促进气道平滑肌增生,参与气道重塑等方式参与气道高反应性过程.本文主要探讨TLR4与在支气管哮喘...     

哮喘黏液高分泌研究进展

哮喘是一种以慢性气道炎症和黏液高分泌为特点的疾病,但黏液的过度分泌在哮喘病理生理中的作用被相对低估了。实际上黏液栓塞对气流受限及气道高反应有相当的影响,严重关系到哮喘的发病率和死亡率。哮喘患者分泌的黏液中主要表现为MUC5AC、MUC5B和MUC2的过度表达,哮喘相关的炎性介质也参与了哮喘黏液高分泌的调控。EGFR级联反应是许多不同刺激导致黏液分泌的共同路径,这些刺激主要包括氧化应激、蛋白酶和细胞因子等。在这些领域的研究有助于我们发现新的抗黏液高分泌药物,并借此加强对哮喘的治疗,提高哮喘患者生活质量。本文从哮喘黏液高分泌特点、调控机制和药物治疗等方面对哮喘黏液高分泌进行综述。     

布地奈德/福莫特罗对支气管哮喘患者血管内皮生长因子及其受体1表达及气道重塑的调控作用

目的支气管哮喘(简称哮喘)是一种慢性气道炎症疾病,伴随气道高反应性、可逆性气流阻塞和气道重塑。血管生成和微血管重塑在气道慢性炎症过程中可能起到重要的作用。血管内皮生长因子(vascular endothelial growth factor,VEGF)是一种促血管生成因子,其生理作用包括促进内皮细胞存活、增殖和迁移。本研究通过检测哮喘患者气道VEGF和VEGF受体1(VEGFR1)的表达,探讨VEGF和哮喘患者气道重塑的关系以及布地奈德/福莫特罗对哮喘患者气道重塑的调控作用。方法支气管组织来源于2006年4月至11月四川大学华西医院经纤维支气管镜行组织活检。23例为中度哮喘患者,20例为对照组。哮喘患者给予规律吸入布地奈德/福莫特罗4.5/160μg,2次/d,持续半年。VEGF和VEGFR1通过免疫组织化学进行检测。AB-PAS和MassonTrichrome染色用于评估气道重塑程度。结果两组之间年龄和性别差异无统计学意义。而两组之间用力肺活量占预计值%,第一秒用力呼气容积占预计值%,PC20,V75占预计值%,V50占预计值%和V25占预计值%的差异有统计学意义。哮喘组患者气道黏液腺增生、平滑肌增厚、上皮下纤维化以及新生血管增加。与对照组比较,VEGF和VEGFR1阳染细胞数目增多,表达增加。VEGF和VEGFR1表达增加与哮喘患者的气道重塑、气流阻塞和气道高反应性呈正相关。规律吸入布地奈德/福莫特罗6个月后,哮喘患者VEGF和VEGFR1表达减少,气道重塑减轻。结论伴随哮喘患者气道血管生成增多和气道重塑,VEGF和VEGFR1表达增加。规律吸入布地奈德/福莫特罗可以通过减少VEGF和VEGFR1表达而减轻哮喘患者气道重塑。阻断VEGF和VEGFR1可能是治疗哮喘的新策略。     

FIZZ1在支气管哮喘发病机制中的研究进展

FIZZ1/RELMα是近年来发现的参与肺部慢性炎性疾病的炎症因子,具有促进肺部血管形成及收缩、抗细胞凋亡、诱导上皮下胶原沉积、促进肺成纤维细胞分化等作用.近几年研究显示FIZZ1 在支气管哮喘中发挥重要作用,参与支气管哮喘气道重塑过程,可刺激肺成纤维细胞分化及气道平滑肌增生、促进肺部血管新生、引起气道高反应性及氧化应激.     

血栓素A2与慢性肺部炎症性疾病

在慢性阻塞性肺疾病、支气管哮喘和肺囊性纤维化等气道慢性炎症性疾病中,常伴有广泛的气道结构破坏、重塑和黏液高分泌等病理改变.炎症介质血栓素A2(TXA2)是花生四烯酸的环氧合酶代谢产物之一,因其诱导血小板聚集、收缩血管及呼吸道平滑肌和刺激气道及血管平滑肌增殖而在这些病理改变中起着重要作用.TXA2作为一种重要的炎症介质,能刺激血管收缩,进而引起气道微血管渗漏,气道黏液增多,刺激气道平滑肌收缩进而引起气道阻力增加,并参与多种肺部炎症反应,近来还发现其可能参与杯状细胞化生和黏液分泌.现就其在肺部炎性疾病的作用作一综述.     

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.     

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.     

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.