大地震创伤后应激障碍患者的心理与神经内分泌变化

目的 :研究唐山大地震所致慢性创伤后应激障碍患者基础血清皮质醇浓度和地塞米松抑制试验。方法 :唐山大地震所致创伤后应激障碍 3 5例 (研究组 )和 3 3例正常人 (对照组 )接受了基础血清皮质醇水平的测定和地塞米松抑制试验。结果 :两组基础血清皮质醇水平比较差异无统计学显著性 ,各组男女之间基础血清皮质醇水平分别比较差异亦无统计学显著性。两组服用相同剂量的地塞米松后 ,研究组血清皮质醇水平低于对照组和对血清皮质醇的抑制作用高于对照组 ,差异均有统计学显著性。各组男女之间的基础血清皮质醇水平、服用地塞米松后血清皮质醇水平和对地塞米松的抑制率比较差异无统计学显著性。结论 :唐山大地震所致慢性PTSD患者对糖皮质激素的敏感性增高而导致PHA轴负反馈抑制增强 ,无性别差异     

Investigation of hormonal male contraception in African men: suppression of spermatogenesis by oral desogestrel with depot testosterone

BACKGROUND: Suppression of spermatogenesis to azoospermia is required for effective hormonal male contraception, but the degree of suppression varies between ethnic groups. We here report the first study of hormonal suppression of spermatogenesis in two African centres using a regimen of oral progestogen with depot testosterone. METHODS A total of 31 healthy men (21 black) were recruited in Cape Town and 21 men in Sagamu, Nigeria. Subjects were randomized to take either 150 or 300 micro g desogestrel daily p.o. with testosterone pellets. In Cape Town, desogestrel was administered for 24 weeks with 400 mg testosterone re-administered 12 weekly. In Sagamu, desogestrel was administered for 52 weeks with 200 mg testosterone (later increased to 400 mg) re-administered 12-weekly. RESULTS: In Cape Town, 22 men completed at least 20 weeks treatment. Azoospermia was achieved in 8/10 and 8/12 men in the 150 micro g and 300 micro g desogestrel groups. Four men in Sagamu withdrew. Azoospermia was achieved in all 17 men in the two groups. There were no significant changes in lipoprotein or haemoglobin concentrations in any group. CONCLUSION: These data demonstrate that the combination of oral desogestrel with depot testosterone is an effective regimen for suppression of spermatogenesis in African as in Caucasian and Chinese men, with azoospermia achieved in a total of 83/98 (85%) men.     

Combating the stress of residency: one school's approach.

Residency is a time of stress and turmoil for many residents. The stresses are varied and great, often involving both personal and professional issues. One institutional mechanism that has been shown to help residents cope with stress is the use of residents' wellness, or assistance, programs. The University of South Florida (USF) College of Medicine developed the USF Residency Assistance Program (RAP) in 1997, modeled after business employee assistance programs but tailored to enhance the well-being of residents. The program was developed in an organized, thoughtful manner starting with a Request for Proposals to all local employee assistance programs and the selection of one of these to run the program. The RAP is broad-based, readily available, easily accessible, totally voluntary and confidential, and not reportable to the state board of medicine. It is well integrated into all residency programs and has had excellent acceptance from the administration; information about access to the RAP is available to all residents through multiple venues. The cost is minimal, at only seven cents a day per resident.The authors present data from the eight years the RAP has been operating, including information on program use, referral rates, acceptance, and types of problems encountered. One suicide occurred during this time period, and the RAP provided a significant role in grief counseling. Assistance programs are critical to the well-being of residents. The USF program presents a model that can be used by other programs around the country.     

Surface modification of poly(ether urethane urea) with modified dehydroepiandrosterone for improved in vivo biostability

In this study, a fatty acid urethane derivative of dehydroepiandrosterone (DHEA) was synthesized and evaluated as a polyurethane additive to increase long-term biostability. The modification was hypothesized to reduce the water solubility of the DHEA and physically anchor the additive in the polyurethane during implantation. Polyurethane film weight loss in water as a function of time was studied to determine the polymer retention of the modified DHEA. The polyurethane film with unmodified DHEA had significant weight loss in the first day (10%) that was previously correlated to rapid leaching of the additive. The polyurethane film with modified DHEA had significantly less weight loss at all time points indicating improved polymer retention. The effect of the modified DHEA additive on the biostability of a poly(ether urethane urea) was examined after 5 weeks of subcutaneous implantation in Sprague-Dawley rats. Optical micrographs and infrared analysis of the specimens indicated that the modified DHEA bloomed to the surface of the film forming a crystalline surface layer approximately 10-15 microns thick. After explantation, this surface layer was intact without measurable differences in surface chemistry as monitored by attenuated total reflectance-Fourier transform infrared spectroscopy. There was no evidence of degradation of the polyurethane underneath the modified DHEA surface layer as compared with the polyurethane control. We have concluded that the modified DHEA self-assembled into a protective surface coating that inhibited degradation of the polyurethane. The roughness of the modified DHEA surface layer prevented adherent cell analysis to determine if the additive retained the ability to down-regulate macrophage activity. Subsequent studies will investigate the ability of surface-modifying additives to modulate cellular respiratory bursts in addition to the formation of an impermeable barrier. This bimodal approach to improving biostability holds great promise in the field of polyurethane biomaterials.     

人类ZAKβ与YWHAZ蛋白相互作用的初步研究

目的研究ZAKβ与YWHAZ蛋白之间的相互作用。方法以ZAKβ为诱饵蛋白,利用酵母双杂交筛选人类肝脏cDNA文库,经GST Pull-down、免疫共沉淀和细胞共定位实验分别验证ZAKβ与猎物蛋白在体外和细胞内的相互作用,构建ZAKβ的截短体以确定相互作用的区域,用磷酸化抗体检测ZAKβ在相互作用中的磷酸化作用,并通过流式细胞仪检测这对蛋白相互作用对细胞周期的影响。结果利用酵母双杂交筛选到一个能与ZAKβ相互作用的蛋白YWHAZ,并在体外和细胞内都验证了这二者的相互作用,发现这两个蛋白都能共定位于293T细胞的胞质中,确定了ZAKβ的N端1~250氨基酸为与YWHAZ蛋白相互作用的区域。体外实验发现了这二者的相互作用涉及到磷酸化反应,发现这对蛋白的相互作用能提高293T细胞的G2期水平。结论首次发现并证实了ZAKβ和YWHAZ之间的相互作用,发现该相互作用涉及到磷酸化过程并能够对细胞周期产生影响。     

The importance of water quality for media preparation

The variability in pregnancy rates achieved among in-vitro fertilization (IVF) clinics may be partially attributable to the disparate quality of the water used in the preparation of culture media. The removal of contaminants in the water is of paramount importance since water constitutes the predominant component in any media formulation. To assist in the selection, operation and maintenance of a water purification system, the level of contaminants must be carefully monitored. Conductivity and resistance are used to measure the purity of natural and ultrapure water respectively. Feed water is analysed by an assortment of direct chemical means to determine the necessary system filtration steps. In general, high quality water can be produced by combined reverse osmosis and electrodeionization of treated tap water. Processed water is supplied to an ultrapure water system to provide final polished water. A detailed water processing protocol is presented along with quality assurance guidelines to ensure the consistent production of high quality ultrapure water suitable for in-vitro human embryo culture.     

Proinflammatory effects of interleukin 1 in the rat air pouch

We have utilized the 6-day air-pouch model in rats to study the local tissue response to interleukin-1 exposure. Injection of either recombinant human interleukin 1 alpha (rIL-1 alpha) or interleukin 1 beta (rIL-1 beta) directly into preformed air pouches caused a 10- to 100-fold increase in the number of white blood cells present within the pouch. On a weight basis, rIL-1 beta was more active than rIL-1 alpha. Polymorphonuclear neutrophils (PMN) represented the majority of cells entering the pouch following either a single injection or repeated daily injections of rIL-1 alpha or rIL-1 beta. Significant increases in the number of mononuclear cells present were observed only following repeated injections. Repeated injections of rIL-1 beta, but not rIL-1 alpha, also caused the accumulation of large amounts of fluid within preformed pouches and a grossly apparent thickening of the connective-tissue lining of the pouch. Microscopic examination of stained sections of pouch lining tissue indicated a proliferation of the connective-tissue elements of the lining and deposition of large quantities of extracellular collagen within the pouch wall. These findings are entirely consistent with a role for interleukin 1 in the development and perpetuation of inflammatory reactions.     

Utilization of a specific in vitro lymphocyte immunostimulation assay as an aid in detection of brucella-infected cattle not detected by serological tests.

Studies using the in vitro lymphocyte stimulation test (LST) were conducted with cattle in a dairy herd with a high percentage of reactors to several serological tests for brucellosis. Lymphocytes were prepared from peripheral bovine blood by the Ficoll-diatrizoate technique. Lymphocytes were cultured using microtitration culture plates. Brucella abortus soluble antigen, at a concentration of 4.4 microgram/culture, was added to the appropriate wells of microtitration culture plates and incubated for 6 days. The lymphocyte stimulation responses were measured by assaying for [3H]thymidine incorporation into DNA. Seroagglutination tests were conducted simultaneously with the LST, and tissues were collected after slaughter of the cattle for bacteriological culture to isolate B. abortus. All 21 animals studied were serologically negative for anti-brucella antibodies. Two of the 21 animals were classified as infected with Brucella by the LST, and B. abortus biotype 1 was isolated from tissues of these same two animals. The LST exhibited significant sensitivity and specificity in this study, and more observations of this nature might strengthen the application of this assay as an aid in the diagnosis of brucellosis.     

甲型副伤寒沙门氏菌体抗原抗血清的简易提纯

目的 单克隆抗体以其结合抗原的专一性用于血清学检验是一种必然趋势,而多克隆机体则以其简易的制备方式在目前仍得到广泛的应用,但多克隆抗体的提纯仍有许多繁琐之处,使其优势受到影响。本试验以甲型副伤寒沙门氏菌体抗原多克隆抗体的制备及提纯为例,提出可行的更简易的提纯方法。方法 利用产G蛋白链球菌,以一种较为简易的特异性结合和解离的方法来纯化甲型副伤寒沙门氏菌体抗原免疫血清。结果 得到了特异性IgG抗体。结论 利用这种纯化方法在实验室简易可行。