21 research outputs found
Priority research questions in atopic dermatitis : an International Eczema Council eDelphi consensus
Recent advances in understanding the complex pathogenesis of atopic dermatitis (AD, also known as eczema or atopic eczema), coupled with the development of new treatments, have led to increased interest from multiple stakeholders. There is a need to prioritize areas for research to inform a coordinated approach to advancing science and patient care
Minimal contraction for tissue-engineered skin substitutes when matured at the air–liquid interface
The structural stability of skin substitutes is critical to avoid aesthetic and functional problems after grafting,
such as contractures and hypertrophic scars. The present study was designed to assess the production steps
having an influence on the contractile behaviour of the tissue-engineered skin made by the self-assembly
approach, where keratinocytes are cultured on tissue-engineered dermis comprised of fibroblasts and the
endogenous extracellular matrix they organized. Thus, different aspects were investigated, such as the
assembly method of the engineered dermis (various sizes and anchoring designs) and the impact of epithelial
cell differentiation (culture submerged in the medium or at the air–liquid interface). To evaluate the
structural stability at the end of the production, the substitutes were detached from their anchorages and
deposited on a soft substrate, and contraction was monitored over 1 week. Collected data were analysed
using a mathematical model to characterize contraction. We observed that the presence of a differentiated
epidermis significantly reduced the amount of contraction experienced by the engineered tissues, independently
of the assembly method used for their production. When the epidermis was terminally differentiated,
the average contraction was only 24 4% and most of the contraction occurred within the first 12 h following
deposition on the substrate. This is 2.2-fold less compared to when the epidermis was cultured under the
submerged condition, or when tissue-engineered dermis was not overlaid with epithelial cells. This study
highlights that the maturation at the air–liquid interface is a critical step in the reconstruction of a tissueengineered
skin that possesses high structural stabilit
L'insertion socio-professionnelle transition majeure de l'existence
In this article, five theoretical models of integration into the labor market are at first presented. Each of these views this integration as a major life transition. Seven research projects, bearing on this topic, are then examined in terms of their goals and their relationships to some of the five models. The practical implications of these projects for psychological education and career counselling are also outlined.Dans cet article, nous présentons d'abord différentes conceptions de l'insertion socio-professionnelle abordées par cinq théoriciennes du développement de la personne, sous l'angle particulier d'une transition majeure de l'existence. Sept projets de recherche portant sur l'insertion socio-professionnelle sont ensuite analysés selon la perspective transitionnelle qui les particularise. Les objectifs et conceptions de la transition sur lesquels reposent chacune de ces recherches sont présentés. Des implications pratiques en matière d'éducation psychologique et de counseling de carrière auprès de populations en démarche d'insertion socio-professionnelle sont proposées
Therapeutic education in atopic dermatitis: A position paper from the International Eczema Council
International audienceBackgroundAtopic dermatitis (AD) is a chronic, inflammatory skin disease that affects as many as 12.5% of children aged 0-17 years and 3% of the adult population. In the United States, 31.6 million children and adults are estimated to be living with AD.ObjectiveTherapeutic patient education (TPE) has proven its value in the management of chronic diseases for which adherence to therapy is suboptimal. This article explores experts' opinions and treatment practices to determine if TPE is a recommended and effective method for treating AD.MethodsForty-two (51%) of 82 Councilors and Associates of the International Eczema Council (IEC), an international group with expertise in AD, responded to an electronic survey on TPE and AD.ResultsMost respondents (97.5%) agreed that TPE should play an important role in the management of AD. Many respondents (82.9%) believed that all patients with AD, regardless of disease severity, could benefit from TPE.LimitationsThe International Eczema Council survey lacks specific information on AD severity.ConclusionsPublications have shown the positive effect of TPE on the course of the disease, the prevention of complications, and the autonomy and quality of patient life. Survey respondents agreed that TPE can improve the quality of patient care and patient satisfaction with care
Dynamic mechanical stimulations induce anisotropy and improve the tensile properties of engineered tissues produced without exogenous scaffolding
Mechanical strength and the production of extracellular matrix (ECM) are essential characteristics for engineered tissues designed to repair and replace connective tissues that are subject to stress and strain. In this study, dynamic mechanical stimulation (DMS) was investigated as a method to improve the mechanical properties of engineered tissues produced without the use of an exogenous scaffold, referred to as the self-assembly approach. This method, based exclusively on the use of human cells without any exogenous scaffolding, allows for the production of a tissue sheet comprised of cells and ECM components synthesized by dermal fibroblasts in vitro. A bioreactor chamber was designed to apply cyclic strain to engineered tissues in order to determine if dynamic culture had an impact on their mechanical properties and ECM organization. Fibroblasts were cultured in the presence of ascorbic acid for 35 days to promote ECM production and allow the formation of a tissue sheet. This sheet was grown on a custom-built anchoring system allowing for easy manipulation and fixation of the tissue in the bioreactor. Following the 35 day period, tissues were maintained for 3 days in static culture (SC), or subjected either to a static mechanical stimulation of 10% strain, or a dynamic DMS with a duty cycle of 10% uniaxial cyclic strain at 1 Hz. ECM was characterized by histology, immunofluorescence labeling and Western blotting. Both static and dynamic mechanical stimulation induced the alignment of assessed cytoskeletal proteins and ECM components parallel to the axis of applied strain and increased the ECM content of the tissues compared to SC. Measurement of the tensile mechanical properties revealed that mechanical stimulation significantly increases both the ultimate tensile strength and tensile modulus of the engineered tissues when compared to the non-stimulated control. Moreover, we demonstrated that cyclic strain significantly increases these parameters when compared to a static-loading stimulation and that mechanical stimulation contributes to the establishment of anisotropy in the structural and mechanical properties of self-assembled tissue sheets
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Therapeutic education in atopic dermatitis: A position paper from the International Eczema Council
BackgroundAtopic dermatitis (AD) is a chronic, inflammatory skin disease that affects as many as 12.5% of children aged 0-17 years and 3% of the adult population. In the United States, 31.6 million children and adults are estimated to be living with AD.ObjectiveTherapeutic patient education (TPE) has proven its value in the management of chronic diseases for which adherence to therapy is suboptimal. This article explores experts' opinions and treatment practices to determine if TPE is a recommended and effective method for treating AD.MethodsForty-two (51%) of 82 Councilors and Associates of the International Eczema Council (IEC), an international group with expertise in AD, responded to an electronic survey on TPE and AD.ResultsMost respondents (97.5%) agreed that TPE should play an important role in the management of AD. Many respondents (82.9%) believed that all patients with AD, regardless of disease severity, could benefit from TPE.LimitationsThe International Eczema Council survey lacks specific information on AD severity.ConclusionsPublications have shown the positive effect of TPE on the course of the disease, the prevention of complications, and the autonomy and quality of patient life. Survey respondents agreed that TPE can improve the quality of patient care and patient satisfaction with care
Mechanical Properties of Tissue-Engineered Vascular Constructs Produced Arterial or Venous Cells
There is a clinical need for better blood vessel substitutes, as current surgical procedures are limited by the availability of suitable autologous vessels and suboptimal behavior of synthetic grafts in small caliber arterial graft (<5 mm) applications. The aim of the present study was to compare the mechanical properties of arterial and venous tissue-engineered vascular constructs produced by the self-assembly approach using cells extracted from either the artery or vein harvested from the same human umbilical cord. The production of a vascular construct comprised of a media and an adventitia (TEVMA) was achieved by rolling a continuous tissue sheet containing both smooth muscle cells and adventitial fibroblasts grown contiguously in the same tissue culture plate. Histology and immunofluorescence staining were used to evaluate the structure and composition of the extracellular matrix of the vascular constructs. The mechanical strength was assessed by uniaxial tensile testing, whereas viscoelastic behavior was evaluated by stepwise stress-relaxation and by cyclic loading hysteresis analysis. Tensile testing showed that the use of arterial cells resulted in stronger and stiffer constructs when compared with those produced using venous cells. Moreover, cyclic loading demonstrated that constructs produced using arterial cells were able to bear higher loads for the same amount of strain when compared with venous constructs. These results indicate that cells isolated from umbilical cord can be used to produce vascular constructs. Arterial constructs possessed superior mechanical properties when compared with venous constructs produced using cells isolated from the same human donor. This study highlights the fact that smooth muscle cells and fibroblasts originating from different cell sources can potentially lead to distinct tissue properties when used in tissue engineering applications.Canadian Institutes of Health ResearchFonds de la recherche en santé du Québe