Dedicated MR receiver coils: a simple design and construction method

We describe a simple method for design and construction of dedicated receiver coils for use in magnetic resonance imaging. We have been successful in constructing dedicated coils for multiple regions of the body using this method.     

人Fas配体蛋白在大肠杆菌中的融合表达与应用

目的：在大肠杆菌中融合表达人Fas配体蛋白。方法：应用RT-PCR技术，从激活的人外周血淋巴细胞中提取总RNA，扩增Fas配体cDNA，克隆入PCR2.1载体，测序验证后，克隆入带有组氨酸盒的表达载体pQE-31，在大肠杆菌中表达，经亲和层析柱纯化后，用SDS-PAGE和Western blot鉴定表达产物。结果：表达的融合蛋白为人Fas配体，其相对分子质量（Mr)为40000。；经透析复性后，具有诱导Jurkat细胞凋亡的作用，用该蛋白分子免疫BALB/c小鼠制备抗血清，以间接ELISA检测了部分自身免疫病与肿瘤患者血清中可溶性的F 苛的含量。结果与进口试剂盒的灵敏性相似。结论：获得FasL单克隆抗体，深入研究FasL的应用提供了材料。     

HTK保护液对尸肾移植器官的影响

近期出版的第5期美国移植杂志(American Journal of Transplantation)报道了两项关于比较HTK和UW保护液对尸肾移植物预后的影响的研究结果,来自美国UNOS数据库和内布拉斯加医学中心大学的数据均显示HTK液对尸肾肾移植后移植肾的早期功能恢复不利.     

Recombinant human interleukin-1 receptor antagonist in the treatment of steroid-resistant graft-versus-host disease

Acute graft-versus-host disease (GVHD) that is resistant to therapy is a highly lethal complication of marrow transplantation. Inflammatory cytokines such as interleukin-1 (IL-1) may be critical mediators of this process. If so, specific inhibition of IL-1 activity with recombinant human IL-1 receptor antagonist (IL-1Ra), a naturally occurring competitive inhibitor of IL-1, may ameliorate acute GVHD. We performed an open-label, phase I/II trial to evaluate the safety and efficacy of IL-1Ra in 17 patients with steroid-resistant GVHD. The IL- 1Ra was administered as a 24-hour continuous infusion over 7 days. The dose was escalated in cohorts of patients from 400 to 3,200 mg/d. Acute GVHD was evaluated in each affected organ and as an overall grade. Stage-specific improvement of acute GVHD occurred in the skin (8 of 14, 57%), gut (9 of 11, 82%), and liver (2 of 11, 18%). Overall, acute GVHD improved by at least one grade in 10 of 16 (63%) patients. Response to therapy was associated with a reduction of tumor necrosis factor-alpha (TNF-alpha) mRNA levels in blood mononuclear cells (P = .001). The only toxicity attributable to IL-1Ra was reversible transaminase elevation in two patients. Inhibition of IL-1 activity with IL-1Ra is safe and has demonstrable efficacy in acute GVHD that failed to respond to conventional treatment. These data provide further evidence that IL-1 is a mediator of GVHD.     

Economic impact of chronic prostatitis

There are four types of prostatitis, including type I (acute bacterial prostatitis), type II (chronic bacterial prostatitis), type III (chronic prostatitis/chronic pelvic pain syndrome, or CP/CPPS), and type IV (asymptomatic inflammatory prostatitis). These prostatitis conditions account for approximately 2 million office visits each year to primary care physicians and urologists. The annual cost to treat prostatitis is approximately $84 million. Compared with control subjects, men with prostatitis incur significantly greater costs, predominantly due to increased outpatient visits and pharmacy expenses. CP/CPPS is the most common type of prostatitis. The condition is characterized by chronic, idiopathic pelviperineal pain. Due to the lack of effective treatments for CP/CPPS, the per-person costs associated with the condition are substantial and are similar to those reported for peripheral neuropathy, low back pain, fibromyalgia, and rheumatoid arthritis. Costs appear to be higher in men with more severe symptoms. Indirect costs (eg, work and productivity loss) are incurred by many patients with CP/CPPS. Identification of effective treatments for CP/CPPS would be expected to substantially reduce the costs associated with the condition.     

Magnetic resonance imaging-detected avascular osteonecrosis in systemic lupus erythematosus: lack of correlation with antiphospholipid antibodies

We determined prospectively the prevalence of avascular osteonecrosis (AON) by magnetic resonance imaging (MRI) of both lower limbs in a group of 40 systemic lupus erythematosus (SLE) patients, and correlated the results with their serum antiphospholipid antibody (APL Ab) status and their glucocorticoid (GC) intake. APL Ab were detected by anticardiolipin ELISA and by lupus anticoagulant assays. Cumulated prednisolone doses were computed by chart review. The prevalence of AON was 37.5%, with most patients being asymptomatic despite involvement of multiple sites. The number of epiphyseal, metaphyseal and diaphyseal AON sites per patient did not differ between APL Ab-positive and APL Ab- negative patients nor between patients with high and low APL Ab titres. By contrast, a striking correlation was found between the prevalence and severity of AON and GC therapy. In conclusion, this prospective MRI study indicates that the prevalence of AON in SLE patients correlates strongly with GC therapy, but not with APL Ab status.      

Tissue-factor coagulant activity of cultured human endothelial and smooth muscle cells and fibroblasts

The tissue-factor (thromboplastic) activity of cultured human endothelial cells and fibroblasts is low at time of transfer into fresh medium but increases 3-10 fold. Endothelial cells reach peak activity (400 U/10(5) cells) 5-8 hr after subculture. Activity in fibroblast cultures peaks (3000-12,000 U/10(5) cells) 7-12 hr after subculture. After attaining maximum activity, endothelial and fibroblast tissue- factor content decreases in a time course similar to other cells studied in this laboratory, approaching basal levels by 24-50 hr after subculture. If medium over fibroblasts is changed every 12 hr, activity can be sustained at the peak level for an additional day but cannot be maintained at a high level indefinitely. The kinetics of expression of smooth muscle cell tissue factor are markedly different from other cell types. There is always a pronounced lag (30 hr or more) before the activity increases, and then, in most cases, there is no subsequent decline in activity even though the cells are not refed or restimulated. The activity of each of these cell types is cryptic but becomes available after freeze-thaw disruption of cells.     

Food Intake in Laboratory Rats Provided Standard and Fenbendazole-supplemented Diets

The benzimidazole anthelmintic fenbendazole (FBZ) is a common and effective treatment for pinworm infestation in laboratory animal colonies. Although many investigators have examined the potential for deleterious biologic effects of FBZ, more subtle aspects of the treatment remain untested. Accordingly, we evaluated differences in food intake when healthy male Sprague–Dawley rats were provided a standard nonmedicated laboratory rodent chow or the same chow supplemented with FBZ. We also tested for a preference for either food type when subjects were provided a choice of the 2 diets. Data from these experiments showed no differences in food intake or body weight when rats were maintained on either standard or FBZ-supplemented chow. When the rats were given access to both the standard and FBZ-supplemented diets, they showed a clear preference for the standard diet. The preference for the standard diet indicates that the rats can discriminate between the 2 foods and may avoid the FBZ-supplemented chow when possible. Investigators conducting experiments during treatment with FBZ in which differences in food preference are relevant should be aware of these data and plan their studies accordingly.Abbreviation: FBZ, fenbendazolePinworm infestation is a common and troublesome situation that can arise in the maintenance and care of laboratory rat colonies.^8,9 A popular and effective treatment strategy relies on a diet that has been supplemented with the benzimidazole anthelmintic fenbendazole (FBZ; methyl 5-[phenylthio]-2-bendzimidazole carbamate).^4,6,7 According to a 1991 toxicology evaluation released by the World Health Organization, therapeutic levels of fenbendazole can be administered throughout the lifetime in rodents without significant toxic side effects.¹¹ Moreover, previous experiments have failed to find carcinogenic effects of FBZ treatment at therapeutic doses (for review, see reference 20). However, various histological changes, such as hepatocellular hypertrophy and bile duct proliferation and hyperplasia, have been reported to occur in dosages exceeding 45 mg/kg.^11,22 In addition, rats maintained on a diet containing FBZ had smaller litter sizes than those on an unmedicated diet.¹⁰ Nevertheless, deleterious effects resulting from therapeutic doses of FBZ appear to be minimal.Therapeutic doses of FBZ have few, if any, behavioral effects. One study¹ found that when FBZ was administered to female rats throughout pregnancy and gestation, the pups showed no deficits in digging maze performance and negative geotaxis, whereas the pregnant dams showed no difference in drinking or weight gain. However, the progeny of the FBZ-treated dams showed decreased performance in running-wheel and Morris water maze tests and demonstrated delayed righting reflex.¹ Nevertheless, adult rats treated with FBZ failed to differ from controls in a variety of tests, including conditioning and timing tasks that are sensitive to neurotoxic drug effects.¹²Although the potential for deleterious effects of FBZ has garnered much interest, more subtle issues remain untested. Diet and taste preference are important factors that may affect many types of experiments, especially those measuring food intake. To address the paucity of information related to intake of FBZ-supplemented food, we measured food intake and weight gain in healthy rats given standard or FBZ-supplemented chow. We also tested for a preference between standard and FBZ-supplemented diets. The data from these experiments indicate that rats consumed normal levels of the medicated diet when it was the only food available and did not alter their intake when switched from standard to FBZ-supplemented chow (or vice versa). Nevertheless, the rats showed a strong preference for the nonmedicated diet when given a choice.