Th1/Th2极化相关因子在血吸虫病肝纤维化发生发展中的作用

血吸虫病肝纤维化是宿主感染血吸虫后发生免疫反应导致的严重病理损害。宿主处于何种免疫应答状态决定了肝纤维化的进展。当宿主体内以Th1免疫应答为主时,不易发生肝纤维化;而宿主体内以Th2免疫应答为主时,易形成肝纤维化。细胞因子及共刺激分子在Th1/Th2极化过程中均发挥重要的作用。本文综述了细胞因子和共刺激分子调控Th1/Th2极化的作用及其与血吸虫病肝纤维化发生、发展相关性的研究进展。     

Th17 细胞在寄生虫感染免疫中的作用

Th17细胞是一种新发现的CD4⁺效应性T细胞亚群。最新研究表明, Th17细胞通过其主要表达产物白细胞介素-17（IL-17）,在寄生虫感染免疫中发挥着重要作用。同时,Th17细胞的诱导及其发挥免疫效应也受到多种细胞因子的调节。目前发现,在抗寄生虫感染过程中,根据宿主自身的免疫状态、感染的严重程度、以及疾病的治疗情况,Th17发挥着保护或促炎的作用。     

Treg/Th17平衡与血吸虫感染免疫

血吸虫感染可诱导调节性T细胞（Treg）和Th17型免疫反应。研究表明,Treg和Th17细胞及其平衡在血吸虫感染中具有非常重要的作用。Treg细胞抑制宿主体内过度病理反应,并有助于血吸虫逃避宿主的免疫攻击;而Th17细胞促进血吸虫感染过程中的免疫病理发展。本文就Treg/Th17平衡与血吸虫感染免疫关系的研究进展作一综述。     

Th17细胞和肠道菌群在炎症性肠病发病中的作用

炎症性肠病(IBD)是一种自身免疫性疾病,发病机制尚未明确,目前认为是由宿主基因、肠道微生物以及生活环境等因素综合作用,引发机体异常免疫应答所致。近年来,Th17细胞与IBD的关系成为研究热点,且越来越多的研究表明,肠道菌群对Th17细胞及其相关细胞因子的调节与IBD发病密切相关。本文就Th17细胞和肠道菌群在IBD发病中的作用作一综述。     

HBV感染相关性肝病中调节性T淋巴细胞和辅助性T淋巴细胞17失衡的研究进展

HBV持续感染与宿主的免疫应答相关,CD4+T淋巴细胞在HBV特异性免疫应答中起重要作用。核苷和核苷酸类药物抗病毒治疗后,HBV特异性T淋巴细胞应答的恢复与CD4+T淋巴细胞亦相关。近年来新发现CD4+T淋巴细胞的2个亚群,即调节性T淋巴细胞(Treg细胞)和辅助性T淋巴细胞(Th)17,它们与HBV持续感染相关疾病的病情进展以及肝损伤相关。初步总结了Treg和Th17的分化及功能,综述了HBV持续感染相关疾病中二者的相互关系及临床抗病毒治疗后二者的变化,旨在为临床进行免疫治疗及评估预后提供帮助。     

辅助性T细胞细胞因子在线虫感染免疫作用中的研究进展

Th细胞在宿主感染线虫后的免疫应答中处于核心位置,其核心作用主要是通过复杂的细胞因子网络实现的。不同的细胞因子在线虫感染中发挥不同的作用,其中Th2细胞因子在多数线虫感染中占主导地位,并且对宿主起保护性免疫作用。本文主要对在线虫感染起重要作用的细胞因子进行综述。     

蠕虫及虫源性分子对自身免疫性疾病的保护作用

机体接触包括蠕虫在内的病源微生物机会减少,尤其在幼年时期免疫系统失去病源微生物的塑造和协调,是导致西方发达国家自身免疫性疾病和过敏性疾病发病率迅速增高的主要原因之一。蠕虫感染能激发强烈的Th2 免疫应答,可以改善Th1 介导的自身免疫性疾病的临床症状和病理过程。日益增多的流行病学及实验研究证实了蠕虫对自身免疫性疾病及过敏性疾病的保护作用,显示了优异的临床应用价值。蠕虫感染能激发强烈的Th2 免疫应答,可以改善Th1 介导的自身免疫性疾病的临床症状和病理过程。目前,蠕虫感染诱导的宿主Th2 免疫偏移已成为感染免疫调节研究的重要模型,并显示了优异的临床应用价值,具有诱人的临床应用前景。然而其负向免疫调控的机制至今尚未明了。本文回顾近年来蠕虫及其分子调节自身免疫性疾病的国内外研究进展,着重探讨蠕虫感染及其分子发挥免疫抑制作用的可能机制。     

白介素17在结核病发生和发展中的免疫应答作用

分泌白介素17(IL-17)的辅助型T细胞17(Th17)参与结核病的免疫应答,并与Th1共同参与对结核病的免疫调控.IL-17对机体防御结核分枝杆菌感染具有保护性作用,它通过促进中性粒细胞的生成和募集,加强干扰素γ的保护性反应,促进肉芽肿的形成而达到控制结核分枝杆菌的作用.但是.IL-17过度表达则会引起机体的损伤,...     

Th17/Treg免疫失衡在血吸虫病肝纤维化中的作用

血吸虫病肝纤维化是宿主感染血吸虫后发生免疫反应所致的一种严重病理性损害。肝脏的免疫应答状态决定了肝纤维化的进程。近期研究发现,Th17和Treg细胞是CD4+T细胞的2个亚群。Th17细胞主要参与炎症反应;Treg细胞主要介导负向调控。Th17/Treg细胞的分化相互抑制、功能反向调节,在正常状况下两者保持平衡。Th17、Treg细胞及其免疫平衡在维持机体内环境的稳定、参与炎症反应、组织损伤、纤维化及多种疾病的发生发展方面发挥着重要的作用。本文就Th17/Treg细胞及其免疫失衡在血吸虫病肝纤维化中的作用进行综述。     

血吸虫及其相关产物在宿主免疫调节中的作用

血吸虫可通过合成、分泌或者排泄多种具有免疫调节功能的分子影响宿主的免疫系统,主要表现为促进Th2免疫效应,抑制Th1/Th17免疫效应.血吸虫感染过程中,其免疫调节效应可以调控宿主固有免疫和适应性免疫,使其能够逃避宿主的免疫攻击,而在人体内长期存活.研究显示血吸虫感染对于过敏性疾病、自身免疫性疾病以及同种异体免疫反应等...     

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.