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.     

Endothelial cells and peripheral blood mononuclear cells are a potential source of extraplacental activin a in preeclampsia

An excessive systemic inflammatory response, involving endothelial cells and leukocytes, underlies the maternal symptoms of preeclampsia. Activin A is raised in preeclampsia, suggesting a possible involvement in its pathophysiology. The placenta is the main source of activin A in normal pregnancy. We investigated whether peripheral blood mononuclear cells (PBMCs) and endothelium, activated by proinflammatory stimuli, were a potential source of activin A in preeclampsia. Both endotoxin and TNFalpha stimulated activin A secretion by PBMCs from nonpregnant, preeclamptic, and matched normal pregnant women (P < 0.05). Pregnancy increased the responsiveness of PBMCs to endotoxin (P < 0.05), whereas only the preeclamptic group were significantly more responsive to TNFalpha (P < 0.05). Human umbilical vein endothelial cells secreted activin A spontaneously and in response to TNFalpha (P < 0.05), but recombinant IL-1beta and IL-6 had no significant effect over the 72-h culture period. Inhibin A and follistatin were undetectable (<2 pg/ml and < 20 pg/ml, respectively) in PBMCs and human umbilical vein endothelial cell culture media. These data suggest that PBMCs and endothelium, activated by TNFalpha, could be extraplacental sources of activin A in preeclampsia. The pathological significance of increased activin A in preeclampsia is unknown, although it may have a role in the mechanisms underlying endothelium dysfunction.     

A model of corrective gene transfer in X-linked ichthyosis

Single gene recessive genetic skin disorders offer attractive prototypes for the development of therapeutic cutaneous gene delivery. We have utilized X-linked ichthyosis (XLI), characterized by loss of function of the steroid sulfatase arylsulfatase C (STS), to develop a model of corrective gene delivery to human skin in vivo. A new retroviral expression vector was produced and utilized to effect STS gene transfer to primary keratinocytes from XLI patients. Transduction was associated with restoration of full-length STS protein expression as well as steroid sulfatase enzymatic activity in proportion to the number of proviral integrations in XLI cells. Transduced and uncorrected XLI keratinocytes, along with normal controls, were then grafted onto immunodeficient mice to regenerate full thickness human epidermis. Unmodified XLI keratinocytes regenerated a hyperkeratotic epidermis lacking STS expression with defective skin barrier function, effectively recapitulating the human disease in vivo. Transduced XLI keratinocytes from the same patients, however, regenerated epidermis histologically indistinguishable from that formed by keratinocytes from patients with normal skin. Transduced XLI epidermis demonstrated STS expression in vivo by immunostaining as well as a normalization of histologic appearance at 5 weeks post-grafting. In addition, transduced XLI epidermis demonstrated a return of barrier function parameters to normal. These findings demonstrate corrective gene delivery in human XLI patient skin tissue at both molecular and functional levels and provide a model of human cutaneous gene therapy.      

Multicentre comparison of the Glasgow Blatchford and Rockall Scores in the prediction of clinical end-points after upper gastrointestinal haemorrhage

Aliment Pharmacol Ther 2011; 34: 470–475

Summary

Background The Glasgow Blatchford Score (GBS) is increasingly being used to predict intervention and outcome following upper gastrointestinal haemorrhage (UGIH). Aim To compare the GBS with both the admission and full Rockall scores in predicting specific clinical end‐points following UGIH. Patients and methods Data on consecutive patients presenting to four UK hospitals were collected. Admission history, clinical and laboratory data, endoscopic findings, treatment and clinical follow‐up were recorded. Using ROC curves, we compared the three scores in the prediction of death, endoscopic or surgical intervention and transfusion. Results A total of 1555 patients (mean age 56.7 years) presented with UGIH during the study period. Seventy‐four (4.8%) died, 223 (14.3%) had endoscopic or surgical intervention and 363 (23.3%) required transfusion. The GBS was similar at predicting death compared with both the admission Rockall (area under ROC curve 0.804 vs. 0.801) and full Rockall score (AUROC 0.741 vs. 0.790). In predicting endo‐surgical intervention, the GBS was superior to the admission Rockall (AUROC 0.858 vs. 0.705; P < 0.00005) and similar to the full Rockall score (AUROC 0.822 vs. 0.797). The GBS was superior to both admission Rockall (AUROC 0.944 vs. 0.756; P < 0.00005) and full Rockall scores (AUROC 0.935 vs. 0.792; P < 0.00005) in predicting need for transfusion. Conclusions Despite not incorporating age, the GBS is as effective as the admission and full Rockall scores in predicting death after UGIH. It is superior to both the admission and full Rockall scores in predicting need for transfusion, and superior to the admission Rockall score in predicting endoscopic or surgical intervention.     

新复合纤维蛋白胶可注射性磷酸钙人工骨的理学特性

目的:检测纤维蛋白胶复合β-磷酸三钙/磷酸二氢钙复合人工骨材料的物理学性能,评价纤维蛋白胶对β-磷酸三钙/磷酸二氢钙骨水泥性能的影响,以及其作为注射型复合人工骨用于修复骨缺损的可行性。方法:实验于2006-12/2007-06在南方医科大学珠江医院中心实验室和华南理工大学生物材料实验室完成。①材料:β-磷酸三钙由上海瑞邦生物材料有限公司提供,磷酸二氢钙为东泰化工赠,纤维蛋白胶购自广州倍绣生物技术有限公司。②复合材料制备:将β-磷酸三钙/磷酸二氢钙骨水泥按3∶1的比例充分混合后,与纤维蛋白胶按凝固后的体积2∶1体积比混合,制成复合人工骨材料。③观察指标:测定复合材料的凝固时间,抗压强度,抗稀散性能,并用扫描电镜观察其煅烧前后的显微结构特征,以未加纤维蛋白胶的磷酸钙水泥为对照(CPC组)。结果:复合人工骨材料的平均初凝时间长于CPC组(P<0.004),终凝时间在初凝时间后2～4 min;复合材料的抗压强度为(14.72±1.81)MPa。复合材料较CPC组有良好的抗稀散性能,扫描电镜发现,纤维蛋白胶贯穿于磷酸钙水泥晶体间,并将磷酸钙水泥晶体紧密连接。煅烧后复合材料的孔径有增大,空隙率为57.28%,并且微孔之间有空隙互相贯通。结论:该骨水泥复合材料凝固时间符合临床操作的需要;抗压强度达到松质骨强度的要求;煅烧后磷酸钙水泥的空隙率明显提高,有利于材料的降解。     

薄层扫描法测定黄芪生脉颗粒中黄芪甲甙含量

目的：制订黄芪生脉颗粒中黄芪甲甙含量测定方法。方法：双波长薄层扫描法，经乙酰洗涤、正丁醇提取和Ｄ１０１大乳吸附树脂柱层析法制备样品，以氯仿－甲醇－水（１３：７：２）下层液为展开剂，检测波长为５１０ｎｍ，参比波长为７００ｎｍ。结果：加标回收率平均为９８．７％（ＲＳＤ＝２．０％，ｎ＝６），标准曲线ｒ＝０．９９６６，重复性ＲＳＤ＝１．４％（ｎ＝５），精密度ＲＳＤ＝２．０％（ｎ＝６）。结论：方法稳定、可靠     

Factors relevant to preventing embolic stroke in patients with non-rheumatic atrial fibrillation

Whether or not to treat patients with non-rheumatic atrial fibrillation with anticoagulants to prevent embolic stroke is a dilemma for physicians. If randomized trials, currently underway, demonstrate a beneficial effect, the dilemma will not be solved because not all of the relevant factors can be addressed by trials. We used current knowledge about non-rheumatic atrial fibrillation and a method of obtaining patient-derived weights for avoiding stroke from eight medically trained subjects, to determine the overall benefit of anticoagulants and to see what factors were relevant and what effect each might have in deciding whether to use anticoagulant therapy. Using standard assumptions, anticoagulants gave an expected benefit for all subjects. The expected benefit (expressed in terms of lives per 1000 saved due to anticoagulants) varied between 5.4 and 46.7. This benefit remained for all subjects when we did a sensitivity analysis for different rates of stroke prevented by anticoagulants and different rates of intracranial hemorrhage caused by anticoagulants. When we used different baseline rates of stroke and different impacts of major hemorrhagic complications the benefit disappeared for 3 and 4 subjects respectively. We found the factors that were most crucial to the decision will not be included in randomized trials; the weight that an individual would place on avoiding embolic stroke vs the risk of intracranial bleeding from anticoagulant therapy; and the rate of embolic stroke that could be expected for the subject at risk. Factors which will be measured in randomized trials, will change results less substantially: the increased risk of major hemorrhages; the proportion of strokes that could be prevented by treatment; the increase in risk of intracranial hemorrhage. This method of analysis suggests that for most patients anticoagulants are beneficial and that the most important factor in determining this result is the value that subjects put on different outcomes.     

Enzyme immunoassays for inhibins, activins and follistatins

In this short review, the authors summarise the inhibin, activin and follistatin assays developed by the Oxford group and collaborators, and some of the main purposes for which they have been applied. Over 500 research publications have used these assays. We also discuss new assays recently developed at the request of our collaborators for particular applications, and comment on outstanding assay problems.