Liposomal Antioxidants for Protection against Oxidant-Induced Damage

Reactive oxygen species (ROS), including superoxide anion, hydrogen peroxide, and hydroxyl radical, can be formed as normal products of aerobic metabolism and can be produced at elevated rates under pathophysiological conditions. Overproduction and/or insufficient removal of ROS result in significant damage to cell structure and functions. In vitro studies showed that antioxidants, when applied directly and at relatively high concentrations to cellular systems, are effective in conferring protection against the damaging actions of ROS, but results from animal and human studies showed that several antioxidants provide only modest benefit and even possible harm. Antioxidants have yet to be rendered into reliable and safe therapies because of their poor solubility, inability to cross membrane barriers, extensive first-pass metabolism, and rapid clearance from cells. There is considerable interest towards the development of drug-delivery systems that would result in the selective delivery of antioxidants to tissues in sufficient concentrations to ameliorate oxidant-induced tissue injuries. Liposomes are biocompatible, biodegradable, and nontoxic artificial phospholipid vesicles that offer the possibility of carrying hydrophilic, hydrophobic, and amphiphilic molecules. This paper focus on the use of liposomes for the delivery of antioxidants in the prevention or treatment of pathological conditions related to oxidative stress

Impact of dynamic computed tomographic angiography on endograft sizing for endovascular aneurysm repair.

Contains fulltext : 80349.pdf (publisher's version ) (Open Access)PURPOSE: To quantify dynamic changes in aortoiliac dimensions using dynamic electrocardiographically (ECG)-gated computed tomographic angiography (CTA) and to investigate any potential impact on preoperative endograft sizing in relation to observer variability. METHODS: Dynamic ECG-gated CTA was performed in 18 patients with abdominal aortic aneurysms. Postprocessing resulted in 11 datasets per patient: 1 static CTA and 10 dynamic CTA series. Vessel diameter, length, and angulation were measured for all phases of the cardiac cycle. The differences between diastolic and systolic aneurysm dimensions were analyzed for significance using paired t tests. To assess intraobserver variability, 20 randomly selected datasets were analyzed twice. Intraobserver repeatability coefficients (RC) were calculated using Bland-Altman analysis. RESULTS: Mean aortic diameter at the proximal neck was 21.4+/-3.0 mm at diastole and 23.2+/-2.9 mm at systole, a mean increase of 1.8+/-0.4 mm (8.5%, p<0.01). The RC for the aortic diameter at the level of the proximal aneurysm neck was 1.9 mm (8.9%). At the distal sealing zones, the mean increase in diameter was 1.7+/-0.3 mm (14.1%, p<0.01) for the right and 1.8+/-0.5 mm (14.2%, p<0.01) for the left common iliac artery (CIA). At both distal sealing zones, the mean increase in CIA diameter exceeded the RC (10.0% for the right CIA and 12.6% for the left CIA). CONCLUSION: The observed changes in aneurysm dimension during the cardiac cycle are small and in the range of intraobserver variability, so dynamic changes in proximal aneurysm neck diameter and aneurysm length likely have little impact on preoperative endograft selection. However, changes in diameter at the distal sealing zones may be relevant to sizing, so distal oversizing of up to 20% should be considered to prevent distal type I endoleak

Kennis beter ontsluiten en benutten met Deltafacts

Binnen universiteiten, kennisinstituten en bij waterbeheerders wordt veel kennis ontwikkeld en vergaard. Om te kunnen blijven innoveren, is het belangrijk deze kennis met elkaar te delen, zodat we stappen kunnen maken richting verdere ontwikkeling van de watersector. Hierin is een wereld te winnen, omdat kennis niet optimaal bekend is, versnipperd is of besloten ligt in moeilijk toegankelijke rapporten. Binnen het STOWA- kennisprogramma Deltaproof spreken de waterschappen de wens uit werk te maken van het ontsluiten van kennis. STOWA pakte de boodschap op en nam het initiatief voor het ontwikkelen van Deltafact

Interplays of psychometric abilities on learning gross anatomy

In recent years, there has been international debate concerning how students learn anatomy. The rapid increase in scientific knowledge has put pressure on the place of anatomy within the medical and allied health professional curricula, as well as the design and structure of anatomy courses. In this regard, relatively little is known about what medical and allied health professions students want from an anatomy course or how they learn it. To assess students’ learning approaches and perceptions of anatomy, a series of psychometric tests were administered to Medical (n=82), Podiatry (n=21), and Pharmacy (n=74) students in the United Kingdom. Analysis of the Anatomy Learning Experience (ALE) questionnaire revealed a predominantly positive attitude towards anatomy and the dissection room, with most valuing cadaveric dissection and not regarding it as a daunting environment. Further to this, analysis of the Approaches to Studying Inventory for Students (ASSIST) revealed predominant preferences for strategic and deep approaches. Personality traits were associated with certain learning approaches; neuroticism with surface (p=0.038), conscientiousness with both a deep and strategic approach (p=0.000 and p=0.060 respectively). Certain personality traits were also found to be associated with anatomy experience e.g. neuroticism and achievement striving felt the most effective way to learn was to get their hands in and feel for structures (p=0.044 and p=0.012 respectively). This study concludes that undergraduate students of medicine, podiatry and pharmacy learn anatomy in slightly different ways. Preparation for classroom activities should centre on the promotion of an optimum learning environment and teaching strategies which promote a deep approach to learning. Understanding students’ personality and learning experiences should help teachers improve the students’ learning of anatomy for effective application to clinical practice

Automatic segmentation, detection and quantification of coronary artery stenoses on CTA

Accurate detection and quantification of coronary artery stenoses is an essential requirement for treatment planning of patients with suspected coronary artery disease. We present a method to automatically detect and quantify coronary artery stenoses in computed tomography coronary angiography. First, centerlines are extracted using a two-point minimum cost path approach and a subsequent refinement step. The resulting centerlines are used as an initialization for lumen segmentation, performed using graph cuts. Then, the expected diameter of the healthy lumen is estimated by applying robust kernel regression to the coronary artery lumen diameter profile. Finally, stenoses are detected and quantified by computing the difference between estimated and expected diameter profiles. We evaluated our method using the data provided in the Coronary Artery Stenoses Detection and Quantification Evaluation Framework. Using 30 testing datasets, the method achieved a detection sensitivity of 29 % and a positive predi

Meta-analysis of type 2 Diabetes in African Americans Consortium

Type 2 diabetes (T2D) is more prevalent in African Americans than in Europeans. However, little is known about the genetic risk in African Americans despite the recent identification of more than 70 T2D loci primarily by genome-wide association studies (GWAS) in individuals of European ancestry. In order to investigate the genetic architecture of T2D in African Americans, the MEta-analysis of type 2 DIabetes in African Americans (MEDIA) Consortium examined 17 GWAS on T2D comprising 8,284 cases and 15,543 controls in African Americans in stage 1 analysis. Single nucleotide polymorphisms (SNPs) association analysis was conducted in each study under the additive model after adjustment for age, sex, study site, and principal components. Meta-analysis of approximately 2.6 million genotyped and imputed SNPs in all studies was conducted using an inverse variance-weighted fixed effect model. Replications were performed to follow up 21 loci in up to 6,061 cases and 5,483 controls in African Americans, and 8,130 cases and 38,987 controls of European ancestry. We identified three known loci (TCF7L2, HMGA2 and KCNQ1) and two novel loci (HLA-B and INS-IGF2) at genome-wide significance (4.15 × 10(-94)<P<5 × 10(-8), odds ratio (OR)  = 1.09 to 1.36). Fine-mapping revealed that 88 of 158 previously identified T2D or glucose homeostasis loci demonstrated nominal to highly significant association (2.2 × 10(-23) < locus-wide P<0.05). These novel and previously identified loci yielded a sibling relative risk of 1.19, explaining 17.5% of the phenotypic variance of T2D on the liability scale in African Americans. Overall, this study identified two novel susceptibility loci for T2D in African Americans. A substantial number of previously reported loci are transferable to African Americans after accounting for linkage disequilibrium, enabling fine mapping of causal variants in trans-ethnic meta-analysis studies.Peer reviewe