亚低温治疗对缺血性卒中纤溶系统的影响

纤溶系统失衡参与了缺血性卒中的病理生理学过程.大多数学者认为缺血性卒中患者的纤溶活性降低,而部分学者认为其纤溶活性增高.亚低温是一种具有巨大潜能并通过多种机制发挥神经保护效应的治疗手段.动物实验证实,亚低温治疗能提高血浆纤溶活性并减少缺血区局部纤溶酶原激活物表达,但相关临床研究较少,而且多局限于亚低温联合其他治疗方法的安全性和协同性的研究.     

亚低温治疗在神经危重症中的应用

亚低温的脑保护作用已得到肯定,近些年来,对亚低温脑保护作用的研究日渐深入,其临床应用也日趋成熟完善.本文对亚低温治疗技术作简要的介绍,并就亚低温治疗在临床神经危重症中的应用研究做一综述.     

急性缺血性卒中的血管内低温治疗

大量动物实验和临床研究表明，血管内低温对缺血性卒中具有神经保护作用。文章从作用机制、临床研究、影响治疗结果的因素以及并发症的防治等方面对缺血性卒中的血管内低温治疗进行了综述。     

亚低温对局灶性脑缺血治疗时间窗的实验研究进展

脑血管病是严重威胁人类生命健康的临床常见病，而缺血性脑血管病占其中的70％，大脑中动脉阻塞（MCAO）是临床上常见的局灶性脑缺血性疾病。目前，对于急性MCAO的治疗已经由单纯的药物治疗发展成为神经介入和（或）药物联合治疗。由于急性脑缺血再通后可以级联一系列再灌注损伤，因此，进行MCAO的动物实验研究具有现实的临床意义。什么时间内实施亚低温治疗才能起到最大限度的神经保护作用，这涉及到亚低温治疗的时间窗问题。作者对亚低温局灶性脑缺血治疗时间窗的实验研究及临床应用前景综述如下。     

诱导性低温治疗急性卒中

轻度低温的神经保护研究在近20年里不断深入，低温正成为一种治疗急性缺血性和出血性卒中很有前景的方法。文章介绍了急性卒中治疗现状、低温的作用机制、诱导性低温治疗急性卒中的实验研究和临床研究、低温的实施方法和并发症的防治。     

磁共振波谱在亚低温治疗缺血性脑卒中的应用

亚低温与神经元损伤具有一定的相关性,对缺血性损伤具有保护作用;磁共振波谱(MRS)是唯一能够无创、客观反映脑内神经生化代谢情况的分析技术可以直接反映亚低温治疗缺血性卒中颅内代谢情况。     

神经保护药治疗急性缺血性卒中:有效还是无效?

尽管动物实验显示神经保护药治疗缺血性卒中有效,但是临床试验却未能重现动物实验的结果.这导致人们开始怀疑这种治疗是否对急性缺血性卒中确实有效.文章概述了相关的争论.     

雌激素对缺血性卒中的神经保护作用机制

大量临床研究和动物实验均表明 ,雌激素对卒中具有神经保护作用 ,其机制相当复杂 ,涉及多个方面。文章就近年来雌激素对缺血性卒中的神经保护作用机制的研究进行了综述     

雌激素对缺血性卒中的神经保护作用机制

大量临床研究和动物实验均表明，雌激素对卒中具有神经保护作用，其机制相当复杂，涉及多个方面。文章就近年来雌激素对缺血性卒中的神经保护作用机制的研究进行了综述。     

全身亚低温对脑缺血保护作用的实验研究进展

在缺血性卒中治疗研究中,脑保护越来越受到重视。其中全身亚低温(32～35℃)方法的显著保护作用及易实施的特点,显示有良好的应用前景。亚低温脑保护的可能机理是降低代谢,抑制神经毒性物质的过度释放,从而保护血脑屏障,减轻脑水肿及改善缺血后低灌注,防止过灌注损伤,以挽救受影响的神经元,达到脑保护的目的。     

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.