Volumetric rendering techniques: applications for three-dimensional imaging of the hip

Volumetric rendering is a new approach to three-dimensional (3D) imaging that overcomes many of the drawbacks of currently available surface-rendering systems. Its application on the Pixar Imaging System in two cases of acetabular fracture was assessed to illustrate the features of the technique. The fast-computing architecture and large memory of this system allow rapid generation of a series of high-quality 3D images in each plane of rotation (x or spinal axis, z or somersaulting axis) that can be viewed as independent static images or as an animated real-time video loop. Editing to remove the normal contralateral hemipelvis enhances appreciation of acetabular abnormalities. Every pixel of computed tomographic data is preserved, allowing representation of both soft tissue and bone as translucent overlap. The presentation of data also allows detection of subtle abnormalities and features and minimizes the artifact generation common in surface-rendered images.     

Gastrointestinal teratomas: CT and US appearance with pathologic correlation

Gastrointestinal teratomas are uncommon, benign neoplasms that occur primarily in children. A retrospective review of five cases (two gastric, one pancreatic, one mesenteric, and one in the lesser omentum) is presented with emphasis on the computed tomographic and ultrasonographic appearances. Principal findings are a well-defined mass with separate cystic and solid components of varying proportions, discrete areas with densities similar to that of fat, or coarse, globular calcifications within the solid component. Recognition of these findings may allow the radiologist to make a correct preoperative diagnosis of teratoma.     

用气相色谱研究抗氧化剂对膜脂肪酸的保护作用

本文应用气相色谱技术直接测定三种生物膜(人红细胞膜,人血小板膜和鼠肝线粒体膜)多不饱和脂肪酸的含量变化,检测脂质过氧化程度。实验证实几种多羟酚类化合物(儿茶精,阿魏酸钠和没食子酸及其衍生物)不同程度地抑制(OH)诱导的脂质过氧化反应,并呈量效和构效关系。这类抗氧化剂对保护生物膜的结构与功能是有益的。     

Intensive care unit delirium is an independent predictor of longer hospital stay: a prospective analysis of 261 non-ventilated patients

Introduction

Delirium occurs in most ventilated patients and is independently associated with more deaths, longer stay, and higher cost. Guidelines recommend monitoring of delirium in all intensive care unit (ICU) patients, though few data exist in non-ventilated patients. The study objective was to determine the relationship between delirium and outcomes among non-ventilated ICU patients.

Method

A prospective cohort investigation of 261 consecutively admitted medical ICU patients not requiring invasive mechanical ventilation during hospitalization at a tertiary-care, university-based hospital between February 2002 and January 2003. ICU nursing staff assessed delirium and level of consciousness at least twice per day using the Confusion Assessment Method for the ICU (CAM-ICU) and Richmond Agitation-Sedation Scale (RASS). Cox regression with time-varying covariates was used to determine the independent relationship between delirium and clinical outcomes.

Results

Of 261 patients, 125 (48%) experienced at least one episode of delirium. Patients who experienced delirium were older (mean ± SD: 56 ± 18 versus 49 ± 17 years; p = 0.002) and more severely ill as measured by Acute Physiology and Chronic Health Evaluation II (APACHE II) scores (median 15, interquartile range (IQR) 10–21 versus 11, IQR 6–16; p < 0.001) compared to their non-delirious counterparts. Patients who experienced delirium had a 29% greater risk of remaining in the ICU on any given day (compared to patients who never developed delirium) even after adjusting for age, gender, race, Charlson co-morbidity score, APACHE II score, and coma (hazard ratio (HR) 1.29; 95% confidence interval (CI) 0.98–1.69, p = 0.07). Similarly, patients who experienced delirium had a 41% greater risk of remaining in the hospital after adjusting for the same covariates (HR 1.41; 95% CI 1.05–1.89, p = 0.023). Hospital mortality was higher among patients who developed delirium (24/125, 19%) versus patients who never developed delirium (8/135, 6%), p = 0.002; however, time to in-hospital death was not significant the adjusted (HR 1.27; 95% CI 0.55–2.98, p = 0.58).

Conclusion

Delirium occurred in nearly half of the non-ventilated ICU patients in this cohort. Even after adjustment for relevant covariates, delirium was found to be an independent predictor of longer hospital stay.     

小鼠Nanog基因的克隆及对人宫颈癌上皮细胞的作用

目的:克隆小鼠Nanog基因并构建带绿色荧光蛋白的真核表达载体pG-Nanog,观察其对人宫颈癌上皮细胞(Hela细胞)中的表达,旨在为进一步观察其对成体细胞的表型变化及细胞增殖奠定前期实验学基础。方法:实验于2006-03/09在西北农林科技大学陕西省干细胞研究中心完成。Nanog基因的克隆参照庄淑珍的方法。Nanog基因真核表达载体的构建参照GeneBank中的小鼠Nanog基因序列,以pNA992为模板扩增Nanog基因,PCR产物以BglⅡ和SacⅡ双酶切,同时将pEGFP-C1用BglⅡ和SacⅡ鉴定,将该质粒命名为pG-Nanog。Hela细胞用含10%新生牛血清的Dulbecco’s改良培养基(Dulbecco’sModifiedEagleMedium,DMEM)培养,转染Hela细胞。转染前1d,在6孔板的每个孔中接种1.2×105个细胞,待细胞生长至60%～70%汇合时,取pG-Nanog与空载体各4μg分别加入500μL无血清无抗生素的DMEM培养液中,同时将6μL稀释于500μL无血清无抗生素的DMEM(干粉)培养液中,将两者混合,室温静置20min,将复合物加入到细胞中,置37℃,体积分数0.05的CO2培养箱中转染24h后吸出复合物加入完全培养基,48h后观察荧光。合成内源对照β-actin,收集转染4d后的细胞提取RNA,反转录为cDNA,然后分别扩增Nanog基因和β-actin基因。采用RT-PCR的方法检测Hela细胞中Nanog基因的表达。结果:①pEGFP-C1载体经双酶切后获得约1kbp的Nanog基因真核表达载体片段,同预期结果相一致,测序结果同GeneBank中的序列同源性达到99.7%。②将转染48h后的Hela细胞置于荧光显微镜下观察,可见明显的荧光,转染pG-Nanog的细胞绿色荧光蛋白集中于细胞核,将转染4d后Hela细胞的总RNA进行RT-PCR检测,产物经琼脂糖电泳分析,只有转染pG-Nanog的细胞中才能够检测到Nanog基因的相应条带。③转染48h后,对细胞进行抗增殖细胞核抗原免疫组化染色,未转染细胞和转染空质粒细胞及转染pG-Nanog细胞染色结果均呈阳性,转染了pG-Nanog的Hela细胞与正常细胞和转染空载体的细胞相比细胞形态发生了一定的改变,细胞表面形成了许多突起。结论:小鼠Nanog基因的克隆、真核表达载体的构建及在Hela细胞中的表达均获得成功,并观察到Hela细胞发生了形态的改变。     

A review of studies of parent-child communication about sexuality and HIV/AIDS in sub-Saharan Africa

Parent-child sexuality communication has been identified as a protective factor for adolescent sexual and reproductive health, including HIV infection. The available literature on this topic in sub-Saharan Africa is increasing; however a systematic review of studies has not been conducted. This article reviews the literature in the area of parental or caregiver and child communication about sexuality and HIV/AIDS in sub-Saharan Africa. A review of peer reviewed literature published between 1980 and April 2011 was conducted. Communication process studies investigating the frequency, content, style, tone of discussions, preferences, as well as associations with and barriers to sexuality communication are reviewed. In addition, studies which examine behavioral associations with parent-child sexuality communication, and intervention studies to improve parent-child sexuality communication are examined. The findings from process studies suggest wide variation in terms of frequency of discussions, with a range of socio-demographic and other factors associated with sexuality communication. Overall, findings demonstrate that discussions tend to be authoritarian and uni-directional, characterized by vague warnings rather than direct, open discussion. Moreover, parents and young people report a number of barriers to open dialogue, including lack of knowledge and skills, as well as cultural norms and taboos. Findings are less clear when it comes to associations between parental communication and adolescent sexual activity and contraception use. However, nascent indications from intervention research suggest positive findings with increases in frequency and comfort of discussions, among other outcomes. Gaps in the research are identified and discussed with implications for future studies.     

Effect of an adjacent base on detection of a point mutation by restriction enzyme digestion

While routinely mapping point mutations within the arginase locus of a collection of hyperargininemic patients, we discovered that a base immediately outside a restriction endonuclease recognition site (TaqI) can eliminate cleavage of this site by this enzyme. The genetic lesion lay in a base immediately flanking a TaqI recognition site within exon 8 of the arginase locus and abolished cutting by approximately 80%. We wish to emphasize the necessity of heeding subtle cues frequently encountered while generating restriction enzyme data, because neither Southern blot maps nor endonuclease digestion of polymerase chain reaction amplified products of exon 8 accurately predicted where the point mutation lay. To our knowledge, this is the first instance of inhibition of cleavage by flanking bases occurring on natural (nonsynthetic) D DNA substrates, i.e., within the clinical setting of characterization of a human genetic disorder.     

灰毡毛忍冬化学成分研究V灰毡毛忍冬素F和G的结构测定

灰毡毛忍冬化学成分研究Ｖ灰毡毛忍冬素Ｆ和Ｇ的结构测定陈敏，吴威巍，沈国强，罗思齐，李惠庭（上海医药工业研究院２０００４０）灰毡毛忍冬（ＬｏｉｎｃｅｒａｍａｃｒａｎｔｈｏｉｄｅｓＨａｎｄ．－Ｍａｚｚ）系忍冬科忍冬属植物，别名大花忍冬，分布于贵州、广西、...