Interactions within the MHC contribute to the genetic architecture of celiac disease.

Interaction analysis of GWAS can detect signal that would be ignored by single variant analysis, yet few robust interactions in humans have been detected. Recent work has highlighted interactions in the MHC region between known HLA risk haplotypes for various autoimmune diseases. To better understand the genetic interactions underlying celiac disease (CD), we have conducted exhaustive genome-wide scans for pairwise interactions in five independent CD case-control studies, using a rapid model-free approach to examine over 500 billion SNP pairs in total.

Comparison of oral surgery task performance in a virtual reality surgical simulator and an animal model using objective measures.

The use of virtual reality (VR) simulation for surgical training has gathered much interest in recent years. Despite increasing popularity and usage, limited work has been carried out in the use of automated objective measures to quantify the extent to which performance in a simulator resembles performance in the operating theatre, and the effects of simulator training on real world performance. To this end, we present a study exploring the effects of VR training on the performance of dentistry students learning a novel oral surgery task.

GWIS--model-free, fast and exhaustive search for epistatic interactions in case-control GWAS.

Background: It has been hypothesized that multivariate analysis and systematic detection of epistatic interactions between explanatory genotyping variables may help resolve the problem of "missing heritability" currently observed in genome-wide association studies (GWAS). However, even the simplest bivariate analysis is still held back by significant statistical and computational challenges that are often addressed by reducing the set of analysed markers. Theoretically, it has been shown that combinations of loci may exist that show weak or no effects individually, but show significant (even complete) explanatory power over phenotype when combined.

Plasma lipidomic analysis of stable and unstable coronary artery disease.

Objective: Traditional risk factors for coronary artery disease (CAD) fail to adequately distinguish patients who have atherosclerotic plaques susceptible to instability from those who have more benign forms. Using plasma lipid profiling, this study aimed to provide insight into disease pathogenesis and evaluate the potential of lipid profiles to assess risk of future plaque instability.

Methods And Results: Plasma lipid profiles containing 305 lipids were measured on 220 individuals (matched healthy controls, n=80; stable angina, n=60; unstable coronary syndrome, n=80) using electrospray-ionisation tandem mass spectrometry.

Towards defining dental drilling competence, part 2: a study of cues and factors in bone drilling.

The study of expertise in surgery aims to facilitate the development of improved training methods by understanding the characteristics of expert practitioners. In this article and its companion, we present our study of the characteristics of competence and expertise in the field of oral surgery. We observed participants of different skill levels as they performed an ex vivo drilling task designed to test the psychomotor skill of distinguishing the material boundaries between tooth and bone.

Towards defining dental drilling competence, part 1: a study of bone drilling technique.

Technical skills are critical for dentists. Computer-based simulation offers a range of potential benefits for surgical training, but to date the development of simulators has not been characterized by a structured investigation of specific mechanisms by which trainees attain competence. This two-part study contributes to the understanding of the manner in which surgical psychomotor skills are acquired so that this knowledge can be incorporated into the design of training simulations.

Impact of patient adherence and test performance on the cost-effectiveness of cervical cancer screening in developing countries: the case of Honduras.

Objective: We examined the impact of patient adherence and screening test performance on the cost-effectiveness of visual inspection with acetic acid (VIA) and Pap smears when used with colposcopy for diagnosis.

Materials And Methods: Cost-effectiveness analysis was performed using computer modeling. The primary outcome was cancer prevalence in the 10 years after screening.

Adipocytokine changes caused by low-carbohydrate compared to conventional diets in obesity.

Modest weight loss causing a decrease in insulin resistance has been linked to favorable changes in the adipocyte cytokines leptin, adiponectin, and tumor necrosis factor-alpha (TNF-alpha), three emerging risk factors of cardiovascular disease. We previously observed a significant reduction in insulin resistance with weight loss in obese subjects on a low-carbohydrate diet. Based on these previous findings, we hypothesize that a low-carbohydrate diet would be more beneficial in changing leptin, TNF-alpha, and adiponectin than a conventional diet.

A community-based education program about cervical cancer improves knowledge and screening behavior in Honduran women.

Objectives: This study examined changes in knowledge and behavior after a community-based cervical cancer education program in Honduras.

Methods: The program consisted of radio broadcasts targeting rural women and presentations to community nurses. The effectiveness of the radio broadcasts was assessed using a cross-sectional design (control groups n = 124, n = 243; intervention group n = 233).

Comparative analysis of long DNA sequences by per element information content using different contexts.

Background: Features of a DNA sequence can be found by compressing the sequence under a suitable model; good compression implies low information content. Good DNA compression models consider repetition, differences between repeats, and base distributions. From a linear DNA sequence, a compression model can produce a linear information sequence.

Cost-effectiveness of a low-carbohydrate diet and a standard diet in severe obesity.

Objective: Low-carbohydrate diets have become a popular alternative to standard diets for weight loss. Our aim was to compare the cost-effectiveness of these two diets.

Research Methods And Procedures: The patient population included 129 severely obese subjects (BMI = 42.

Free fatty acids, insulin resistance, and corrected qt intervals in morbid obesity: effect of weight loss during 6 months with differing dietary interventions.

Objective: To assess whether shortening of the corrected QT (QTc) interval is most closely associated with changes in weight, insulin resistance, or free fatty acids (FFAs) (or some combination of these factors).

Methods: We randomized 75 severely obese subjects without diabetes to either a low-carbohydrate or a conventional low-fat weight-loss diet for 6 months. We measured QTc, insulin sensitivity, body mass index, and FFAs at baseline and at 6 months.

A randomized study comparing the effects of a low-carbohydrate diet and a conventional diet on lipoprotein subfractions and C-reactive protein levels in patients with severe obesity.

Purpose: To compare the effects of a low-carbohydrate diet and a conventional (fat- and calorie-restricted) diet on lipoprotein subfractions and inflammation in severely obese subjects.

Methods: We compared changes in lipoprotein subfractions and C-reactive protein levels in 78 severely obese subjects, including 86% with either diabetes or metabolic syndrome, who were randomly assigned to either a low-carbohydrate or conventional diet for 6 months.

Results: Subjects on a low-carbohydrate diet experienced a greater decrease in large very low-density lipoprotein (VLDL) levels (difference = -0.

Use of volunteer medical brigades to assess growth in Honduras.

We endeavored to determine whether a visiting volunteer medical group could effectively measure growth status among children in a developing country, identify predictors of poor growth, and thus participate in nutritional surveillance. Cross-sectional measurements of growth and diagnosis of current clinical conditions were made. A sample of 3284 Honduran children aged 2-11 years who sought care from volunteer medical brigades between January 2000 and May 2001 were included in the study.

The effects of low-carbohydrate versus conventional weight loss diets in severely obese adults: one-year follow-up of a randomized trial.

Background: A previous paper reported the 6-month comparison of weight loss and metabolic changes in obese adults randomly assigned to either a low-carbohydrate diet or a conventional weight loss diet.

Objective: To review the 1-year outcomes between these diets.

Design: Randomized trial.

A low-carbohydrate as compared with a low-fat diet in severe obesity.

Background: The effects of a carbohydrate-restricted diet on weight loss and risk factors for atherosclerosis have been incompletely assessed.

Methods: We randomly assigned 132 severely obese subjects (including 77 blacks and 23 women) with a mean body-mass index of 43 and a high prevalence of diabetes (39 percent) or the metabolic syndrome (43 percent) to a carbohydrate-restricted (low-carbohydrate) diet or a calorie- and fat-restricted (low-fat) diet.

Results: Seventy-nine subjects completed the six-month study.