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...     

靶向Toll样受体4治疗支气管哮喘的价值

<正>支气管哮喘(哮喘)是多基因参与的具有遗传易感性的慢性气道炎症性疾病,其发病涉及多种炎症细胞、炎症介质和复杂的细胞因子网络,以血清IgE增高、气道炎症、气道高反应性和气道重塑为显著的临床特征~([1])。Toll样受体(Tolllike receptors,TLR)是果蝇受体Toll同源物,作为固有免疫系统的一种重要的模式识别受体,连接着机体固有免疫和适应性免疫。目前已鉴定人类14种TLR。越来越多的证据表     

地塞米松对支气管哮喘大鼠气道重塑及气道平滑肌中Toll样受体4表达的影响

气道炎症和气道重塑是支气管哮喘(简称哮喘)发生、发展的重要环节,但其发病机制尚未完全明确[1].Toll样受体(Toll like receptor,TLR)是天然免疫和获得性免疫的桥梁[2],研究结果表明,TLR在哮喘的发生、发展中可能起着较为重要的作用[3].地塞米松是治疗哮喘的经典药物,对哮喘的气道炎症和气道重塑均有改善作用,但其作用机制不明.因此,我们将建立哮喘动物模型,从整体水平探讨地塞米松治疗对哮喘气道重塑以及哮喘气道平滑肌中TLR4表达的影响.     

ERK信号传导途径对人气道平滑肌细胞增殖与凋亡及其相关基因表达的影响

气道重塑是慢性支气管哮喘(简称哮喘)的重要病理特征,是哮喘不可逆气流受限和气道高反应性的病理基础 [1-2].气道重塑可加重气道的高反应性,导致肺功能持续性与进行性损害.     

生长因子与气道重塑——生长因子在支气管哮喘气道重塑过程中作用的新进展

支气管哮喘(简称哮喘)是由多种细胞和细胞组分参与的气道慢性炎症性疾病.气道重塑在哮喘早期即可出现,并随着病情进展而加重,参与了哮喘的整个慢性炎症过程,哮喘症状的持续存在、严重程度及气道高反应性均与气道重塑密切相关.因此,理解气道重塑如何促进哮喘进展就成为了更好治疗和管理疾病的关键.生长因子是一类调节细胞生长、分化的多肽类物质,与生长发育、分化、肿瘤等均有密切关系.近年研究显示多种生长因子参与哮喘气道重塑过程.     

054 白介素4受体与支气管哮喘

支气管哮喘(哮喘)是由多种细胞特别是T细胞、肥大细胞和嗜酸粒细胞介导的慢性气道炎症,以气道高反应性和可逆性气道阻塞为特征.白介素4受体(IL-4R)的α亚基作为IL-4和IL-13的受体,参与了哮喘的病理生理过程.本文就IL-4R的生物学功能及其与哮喘关系的研究进展作一.     

Th17细胞及其在支气管哮喘发病中的作用

Th17细胞是一类新型的CD4+T细胞,STAT3、RORγt和RORα等参与了其分化调控.最近,大量研究表明,Th17及其相关的细胞因子在支气管哮喘中起着重要的作用,参与了气道炎症、气道重塑以及气道高反应性.     

腺苷受体与支气管哮喘治疗研究新进展

腺苷受体在哮喘气道炎症中的作用已受到广泛的重视,包括促进哮喘患者气道炎症介质合成和分泌,参与支气管哮喘的气道炎症、气道高反应性及支气管收缩反应的发生和发展。本文就腺苷受体在支气管哮喘发病机制中的作用,及其在哮喘治疗中的研究价值作一综述。     

生长因子与气道重塑——生长因子在支气管哮喘气道重塑过程中作用的新进展

支气管哮喘（简称哮喘）是由多种细胞和细胞组分参与的气道慢性炎症性疾病。气道重塑在哮喘早期即可出现,并随着病情进展而加重,参与了哮喘的整个慢性炎症过程,哮喘症状的持续存在、严重程度及气道高反应性均与气道重塑密切相关。因此,理解气道重塑如何促进哮喘进展就成为了更好治疗和管理疾病的关键。生长因子是一类调节细胞生长、分化的多肽类物质,与生长发育、分化、肿瘤等均有密切关系。近年研究显示多种生长因子参与哮喘气道重塑过程。     

CpG的信号传递机制及其在支气管哮喘等过敏性疾病的应用

支气管哮喘在全球范围特别是发达国家的发病率迅速增加.这被认为与患者幼年时期没有充分暴露在细菌或细菌产物环境下而导致过敏易感性增加有关.CpG-脱氧核苷酸是模拟细菌DNA的合成核苷酸链,可以通过Toll样受体(TLR)被细胞识别,并通过TLR/核因子κB(NF-κB)途径和MAPK途径等诱导Th1型细胞反应,下调Th2型细胞反应,调节免疫应答类型.动物实验证实其可以有效抑制哮喘模型的气道炎症、气道高反应性和气道重塑等,在临床实验中亦已开展诸多研究,因此有关CpG及其作用机制的研究可能成为支气管哮喘治疗的新突破口.     

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.