Transcription-mediated supercoiling regulates genome folding and loop formation.

The chromatin fiber folds into loops, but the mechanisms controlling loop extrusion are still poorly understood. Using super-resolution microscopy, we visualize that loops in intact nuclei are formed by a scaffold of cohesin complexes from which the DNA protrudes. RNA polymerase II decorates the top of the loops and is physically segregated from cohesin. Augmented looping upon increased loading of cohesin on chromosomes causes disruption of Lamin at the nuclear rim and chromatin blending, a homogeneous distribution of chromatin within the nucleus. Altering supercoiling via either transcription or topoisomerase inhibition counteracts chromatin blending, increases chromatin condensation, disrupts loop formation, and leads to altered cohesin distribution and mobility on chromatin. Overall, negative supercoiling generated by transcription is an important regulator of loop formation in vivo.

An optical flow-based state-space model of the vocal folds.

High-speed movies of the vocal fold vibration are valuable data to reveal vocal fold features for voice pathology diagnosis. This work presents a suitable Bayesian model and a purely theoretical discussion for further development of a framework for continuum biomechanical features estimation. A linear and Gaussian nonstationary state-space model is proposed and thoroughly discussed. The evolution model is based on a self-sustained three-dimensional finite element model of the vocal folds, and the observation model involves a dense optical flow algorithm. The results show that the method is able to capture different deformation patterns between the computed optical flow and the finite element deformation, controlled by the choice of the model tissue parameters.

A numerical strategy for finite element modeling of frictionless asymmetric vocal fold collision.

Analysis of voice pathologies may require vocal fold models that include relevant features such as vocal fold asymmetric collision. The present study numerically addresses the problem of frictionless asymmetric collision in a self-sustained three-dimensional continuum model of the vocal folds. Theoretical background and numerical analysis of the finite-element position-based contact model are presented, along with validation. A novel contact detection mechanism capable to detect collision in asymmetric oscillations is developed. The effect of inexact contact constraint enforcement on vocal fold dynamics is examined by different variational methods for inequality constrained minimization problems, namely, the Lagrange multiplier method and the penalty method. In contrast to the penalty solution, which is related to classical spring-like contact forces, numerical examples show that the parameter-independent Lagrange multiplier solution is more robust and accurate in the estimation of dynamical and mechanical features at vocal fold contact. Furthermore, special attention is paid to the temporal integration schemes in relation to the contact problem, the results suggesting an advantage of highly diffusive schemes. Finally, vocal fold contact enforcement is shown to affect asymmetric oscillations. The present model may be adapted to existing vocal fold models, which may contribute to a better understanding of the effect of the nonlinear contact phenomenon on phonation. Copyright © 2016 John Wiley & Sons, Ltd.

ShopSmart 4 Health - protocol of a skills-based randomised controlled trial promoting fruit and vegetable consumption among socioeconomically disadvantaged women.

BACKGROUND: There is a need for evidence on the most effective and cost-effective approaches for promoting healthy eating among groups that do not meet dietary recommendations for good health, such as those with low incomes or experiencing socioeconomic disadvantage. This paper describes the ShopSmart 4 Health study, a randomised controlled trial conducted by Deakin University, Coles Supermarkets and the Heart Foundation, to investigate the effectiveness and cost-effectiveness of a skill-building intervention for promoting increased purchasing and consumption of fruits and vegetables amongst women of low socioeconomic position (SEP). METHODS/DESIGN: ShopSmart 4 Health employed a randomised controlled trial design. Women aged 18-60 years, holding a Coles store loyalty card, who shopped at Coles stores within socioeconomically disadvantaged neighbourhoods and met low-income eligibility criteria were invited to participate. Consenting women completed a baseline survey assessing food shopping and eating habits and food-related behaviours and attitudes. On receipt of their completed survey, women were randomised to either a skill-building intervention or a wait-list control condition. Intervention effects will be evaluated via self-completion surveys and using supermarket transaction sales data, collected at pre- and post-intervention and 6-month follow-up. An economic evaluation from a societal perspective using a cost-consequences approach will compare the costs and outcomes between intervention and control groups. Process evaluation will be undertaken to identify perceived value and effects of intervention components. DISCUSSION: This study will provide data to address the currently limited evidence base regarding the effectiveness and cost-effectiveness of skill-building intervention strategies aimed at increasing fruit and vegetable consumption among socioeconomically disadvantaged women, a target group at high risk of poor diets. TRIAL REGISTRATION: Current Controlled Trials ISRCTN48771770.

A dietitian-led clinic for patients receiving (chemo)radiotherapy for head and neck cancer.

PURPOSE: Malnutrition is prevalent in head and neck cancer patients and is associated with poorer outcomes and increased health care costs. This study aimed to evaluate the acceptability, organisational efficiency and clinical outcomes of a dietitian-led head and neck cancer clinic. METHODS: Two consecutive, independent, patient cohorts were studied with a pre-post-test design of 98 patients prior to the introduction of a dietitian-led clinic (DLC) and the subsequent 100 patients who attended the newly formulated DLC. The two groups were compared for frequency of dietitian intervention, weight loss, enteral feeding, hospital admissions and post-treatment medical follow-up requirements. RESULTS: Nutritional management in a DLC was associated with reduced nutrition-related admissions from 12% to 4.5% (p = 0.0029), unplanned nasogastric tube insertions from 75% to 39% (p = 0.02), improved transition to oral diet post-radiotherapy from 68.3% to 76.7% (p = 0.10) and reduced radiation oncologist review at 2 weeks post-radiotherapy from 32% to 15% patients (p = 0.009) compared to the cohort prior to the DLC. CONCLUSIONS: A dietitian-led head and neck cancer clinic is associated with improved efficiency and nutritional management of head and neck cancer patients and offers a feasible model of care.

Infección en quemaduras graves. Nuevas perspectivas de tratamiento en atención primaria / No disponible

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