Small interfering RNA inhibits SARS-CoV nucleocapsid gene expression in cultured cells and mouse muscles

SARS-CoV isa newly identified coronavirus that causes severe acute respiratory syndrome （SARS）. Currently, there is no effective method available for prophylaxis and treatment of SARS-CoVinfections. In the present study, the influence of small interfering RNA （siRNA） on SARS-CoV nucleocapsid （N） protein expression was detected in cultured cells and mouse muscles. Four siRNA expression cassettes driven by mouse U6 promoter targeting SARS-CoV N gene were prepared, and their inhibitory effects on expression of N and enhanced green fluorescence protein （EGFP） fusion protein were observed.     

溴莫尼定对视网膜缺血性损伤神经保护作用的实验研究

目的：探讨溴莫尼定(brimonidine)对视网膜缺血性损伤神经的保护作用。方法：新西兰大耳白兔32只，随机分为正常对照组、生理盐水治疗组、噻吗心安(timolol)治疗组、brimonidine治疗组，每组8只。后3组为损伤治疗组，通过生理盐水前房高压灌注的方法，制成视网膜缺血动物模型，在视网膜缺血前lh其结膜囊内分剐给予生理盐水、0．5％timolol眼液或0．2％brimonidine眼液局部治疗。在灌注后7d，观察图形视网膜电图(P-ERG)b波振幅变化，并进行组织形态学观察和视网膜神经节细胞(RGC)计数分析。结果：灌注后7d，3个损伤治疗组相对b波振幅恢复率为：7％、11％和64％，RGC标准丢失率为：43％、38％和12％，brimori-die治疗组视网膜组织形态结构接近正常对照组，而生理盐水治疗组和timolol治疗组视网膜内层组织结构损伤明显。结论：Brimonidine局部治疗对缺血诱导的视网膜结构和功能的损害有明显的神经保护作用。     

Enlarged adenomectomy for enclosed prolactinomas: A preliminary study of 26 cases

Summary Preliminary results obtained from 26 cases of prolactinomas less than 20 mm in diameter after treatment by enlarged adenomectomy are described.The operation consisted in removal of the adenoma, a layer of normal pituitary at the outer edge of the tumour and the pituitary capsule in contact with the sellar meninges. 24 women and 2 men were involved whose prolactin levels (PRL) were less than 200 ng/ ml. All presented abnormal PRL responses to Thyrotropin releasing hormone (TRH) and Metoclopramide (MCP) tests and an absence of a nocturnal rise in the sleep cycle study. Postoperatively, three patients developed transitory diabetes insipidus and five transitory adrenal insufficiency. Gonadotropin reserve was always found normal. All 24 women resumed normal menstrual cycles and two became pregnant within one year. From a serological viewpoint, after surgery 100% of patients were found to be normal for levels of prolactin but only 85% turned to normal dynamic tests. The results of this small series of enlarged adenomectomies seem better than those obtained using selective adenomectomy, but must be confirmed with time.     

Urinary mercapturic acid diastereoisomers in rats subchronically exposed to styrene and ethanol

 Styrene is stereoselectively oxidized by cytochrome P450 to its reactive metabolite, styrene oxide. The (R)- and (S)-enantiomers of styrene oxide can be conjugated with glutathione (GSH) to both (R)- and (S)-diastereoisomers of the specific mercapturic acids, N-acetyl-S-(1-phenyl-2-hydroxyethyl)-L-cysteine (M1) and N-acetyl-S-(2-phenyl-2-hydroxyethyl)-L-cysteine (M2). Several investigations have indicated different toxic potential of the (R)- and (S)-configurations of styrene oxide and its GSH- and N-acetyl-conjugates. In this study the mercapturic acid diastereoisomers were measured in the urine of rats exposed to styrene in combination with ethanol, a good inducer of styrene metabolism. Male Sprague-Dawley rats were given an isocaloric liquid diet containing ethanol (5% w/v) for 3 weeks. Starting from the 2nd week, the animals were also exposed to styrene vapours (300 ppm, 6 h/day, 5 days/week) in a dynamic exposure chamber. Both the (R)- and (S)-diastereoisomers of the M1 and M2 as well as the conventional biomarkers, mandelic acid (MA) and phenylglyoxylic acid (PGA) were measured in urinary samples. Approximately 30 and 25% reduction of the levels of brain non-protein sulfhydryls (NPS) was observed in the animals given styrene and ethanol, respectively, while the combined ethanol and styrene treatment resulted in a 60% decrease. Ethanol consumption also resulted in higher urinary levels of the M1-R, M1-S and M2 metabolites associated with increased M1-R/S ratio and higher urinary MA excretion compared to animals treated with styrene. These results suggest that the urinary mercapturic acid diastereoisomers may be used as a noninvasive tool to examine stereoselective patterns of styrene metabolism in vivo, as well as their alterations caused by ethanol. These compound-specific mercapturic acids may also be valuable indicators of styrene-induced disorders of GSH homeostasis in nonaccessible organs. Received: 19 December 1995/Accepted: 10 May 1996     

Herpetic croup: two case reports and a review of the literature

Croup is an acute infectious illness usually occurring in children; it is characterized by brassy cough and stridor. The main pathogens include mainly parainfluenza and influenza viruses. Recently there have been reports of prolonged croup caused by the herpes simplex viruses. We report two cases of prolonged croup due to herpes simplex types 1 and 2. We also review and summarize the reported pediatric cases of herpetic croup.     

Neutralization Susceptibility of B Subtype Variant B' Primary HIV-1 Isolates

Susceptibility to autologous and heterologous neutralization of primary human immunodeficiency virus (HIV)-1 isolates belonging to subtype B, to the B'-variant of subtype B or to subtype F from infected individuals residing in Rio de Janeiro was assayed. A lower infectivity of the B'- and F isolates when compared to the classical B-subtype HIV-1 isolates was observed. Comparisons of neutralization susceptibilities were carried out for 19 B-subtype, 11 B'-variant and two F-subtype HIV-1 isolates with plasma from autologous and heterologous samples. Frequency of autologous neutralization was slightly lower for B-subtype isolates in comparison to B'-variant isolates. Heterologous intra-subtype neutralization was significantly lower for B-subtype than for the B'-variant or the F-subtype isolates. While B-subtype isolates were neutralized by most anti-F-subtype plasma, F-subtype isolates, although most susceptible to F-subtype antibodies, were highly susceptible to neutralization by anti-B-subtype antibodies. Cross-neutralization for B'-variant and B-subtype isolates was not as extensive as observed for B- and F-subtype isolates. However, the results presented indicate a quite extensive cross-neutralization between Brazilian HIV-1 isolates.     

A brief study of the selectivity of norbinaltorphimine, (-)-cyclofoxy, and (+)-cyclofoxy among opioid receptor subtypes in vitro

Norbinaltorphimine (nor-BNI) is a bifunctional reagent developed as a selective antagonist of the kappa opioid receptor. In this paper we examined the in vitro selectivity of nor-BNI, 6-desoxy-6 beta-fluoronaltrexone (cycloFOXY), and the enantiomer of cycloFOXY, among opioid receptor subtypes. Nor BNI exhibited the highest affinity for kappa binding sites labeled by 3H-U69593 (Ki = 1.8nM), and was 27- to 29-fold less potent at mu and delta binding sites. In contrast, cycloFOXY had the highest affinity for mu binding sites (Ki = 2.62 nM), and bound to kappa and delta binding sites with Ki's of 9.3 nM and 89 nM, respectively. The enantiomer of cycloFOXY, did not inhibit binding even at concentrations greater than 10 microM, validating in part the use of 18F-labeled (+)-cycloFOXY to estimate "non-specific binding" in positron emission tomography. Additionally, we report that (S,S)-U50 488 and (R.R)-U50 488 bind to kappa binding sites labeled by 3H-U69 593 with Ki's of 0.89 nM and 299 nM, respectively.     

No-scalpel vasectomy (NSV) procedure and nursing care

The no-scalpel vasectomy technique, introduced by a Chinese surgeon in 1974, is increasingly becoming the method of choice for permanent male sterilization. Conventional vasectomy is being challenged by the new procedure, which results in less pain, fewer infections, and a smaller wound. The use of 2 specially designed instruments lessens tissue damage from the procedure and reduces time required for the operation. In the United States, Dr. Mark Goldstein of Cornell Medical Center, New York City, has instructed surgeons in the no-scalpel technique. The Association for Voluntary Surgical Contraception has also promoted no-scalpel vasectomy, which is gaining popularity among urologists worldwide. The procedure was developed in China by Dr. Li Shunquiang of the Chongquing Family Planning Scientific Research Institute and has been performed on over 8 million men. Statistics reveal that this method produces a smaller singular incision and also reduces postoperative infection and hematoma. In China, the rate of hematoma in 179,741 men was 0.09% and the rate for infections was 0.91%. In a New York study, 238 men had no evidence of infection or hematoma following no-scalpel vasectomy. Since the technique was introduced in 1974, urologic surgeons have responded to the need to offer alternatives for male contraception. Under the direction of Dr. Shunquiang, surgeons received the necessary training to bring the no-scalpel vasectomy to their respective countries. Dr. Marc Goldstein was the first United States urologic surgeon to be trained in this method. By December 1990, data reported by the Association for Voluntary Surgical Contraception revealed that more than 125 United States physicians were trained in no-scalpel vasectomy. This new option is becoming an increasingly popular method for both patients and urologic surgeons.