脑出血周围缺血半暗带及其乏氧显像

急性脑出血时血肿周围脑组织存在不同程度的低灌注,但是否存在缺血半暗带,目前的临床监测方法还未得出一致的结论。作为能够检测处于功能障碍但仍然存活的脑组织的一种成像技术,乏氧显像有助于确认血肿周围缺血半暗带并指导临床对急性脑出血患者的个体化治疗。     

脑出血血肿周围局部脑血流的检测

影像学技术是研究脑血流的主要手段,文章综述了各种神经影像学技术对脑出血血肿周围半暗带的定义以及脑出血血肿周围局部脑血流的研究现状。     

急性脑出血继发缺血半暗带的研究进展

急性脑出血后血肿周边和远隔部位可出现不同程度的局部脑血流下降,其下降程度可能与血肿的大小、部位及出血时间有关。动物实验已证明,血肿周边可出现缺血半暗带,但在临床试验中并未取得一致结论。弥散加权成像和质子磁共振频谱等成像技术有助于显示血肿周边缺血半暗带,以指导临床对急性脑出血患者的个体化治疗。     

急性脑出血继发缺血半暗带的研究进展

急性脑出血后血肿周边和远隔部位可出现不同程度的局部脑血流下降，其下降程度可能与血肿的大小、部位及出血时间有关。动物实验已证明，血肿周边可出现缺血半暗带，但在临床试验中并未取得一致结论。弥散加权成像和质子磁共振频谱等成像技术有助于显示血肿周边缺血半暗带，以指导临床对急性脑出血患者的个体化治疗。     

缺血半暗带的神经影像学判定

精确地判断缺血半暗带的存在 ,是临床治疗缺血性卒中成功与否的关键。为此 ,文章对缺血半暗带的血流阈值、常规正电子发射体层摄影术及特殊显像剂的应用、功能磁共振及其他相关神经影像学检查方法作了介绍     

急性卒中缺血半暗带的CT灌注成像

CT灌注成像能准确和及时地提供卒中后脑组织血流动力学参数,并且与当前公认的脑血流动力学测量手段——氙-CT、功能磁共振成像和正电子发射体层摄影等测得的参数有很好的相关性。因此,CT灌注成像在判断卒中后缺血半暗带研究中的应用日益广泛。     

急性卒中患者的缺血半暗带评价

卒中的发病率、致残率和死亡率均很高.缺血半暗带评价对于指导临床治疗和评估预后具有非常重要的意义.目前,可采用MRI、CT、正电子发射体层摄影和单光子发射计算机体层摄影等影像学技术评价缺血半暗带.     

缺血半暗带的神经影像学判定

精确地判断缺血半暗带的存在，是临床治疗缺血性卒中成功与否的关键。为此，文章对缺血半暗带的血流阈值、常规正电子发射体层摄影术及特殊显像剂的应用、功能磁共振及其他相关神经影像学检查方法作了介绍。     

缺血半暗带的检测MRI还是PET?

缺血半暗带概念的提出为缺血性卒中的超早期治疗明确了方向,但在如何迅速准确获得半暗带信息,即如何选择半暗带的测量方法时,是采用弥散加权成像/灌注加权成像不匹配,还是采用正电子发射体层摄影尚存争议。文章就此问题做了回顾。     

缺血半暗带的检测 MRI还是PET？

缺血半暗带概念的提出为缺血性卒中的超早期治疗明确了方向，但在如何迅速准确获得半暗带信息，即如何选择半暗带的测量方法时，是采用弥散加权成像催注加权成像不匹配，还是采用正电子发射体层摄影尚存争议。文章就此问题做了回顾。     

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.