Decellularised cartilage ECM culture coatings drive rapid and robust chondrogenic differentiation of human periosteal cells

The control of cell behaviour in an effort to create highly homogeneous cultures is becoming an area of intense research, both to elucidate fundamental biology and for regenerative applications. The extracellular matrix (ECM) controls many cellular processes in vivo, and as such is a rich source of cues that may be translated in vitro. Herein, we describe the creation of cell culture coatings from porcine decellularised hyaline cartilage through enzymatic digestion. Surprisingly, heat-mediated sterilisation created a coating with the capacity to rapidly and robustly induce chondrogenic differentiation of human periosteal cells. This differentiation was validated through the alteration of cell phenotype from a fibroblastic to a cuboidal/cobblestone chondrocyte-like appearance. Moreover, chondrogenic gene expression further supported this observation, where cells cultured on heat sterilised ECM-coated plastic displayed higher expression of COL2A1, ACAN and PRG4 (p 0.05) compared to non-coated plastic cultures. Interestingly, COL2A1 and ACAN expression in this context were sensitive to initial cell density; however, SOX9 expression appeared to be mainly driven by the coating independent of seeding density. The creation of a highly chondrogenic coating may provide a cost-effective solution for the differentiation and/or expansion of human chondrocytes aimed towards cartilage repair strategies

Biomimetic strategies for fracture repair: engineering the cell microenvironment for directed tissue formation

Complications resulting from impaired fracture healing have major clinical implications on fracture management strategies. Novel concepts taken from developmental biology have driven research strategies towards the elaboration of regenerative approaches that can truly harness the complex cellular events involved in tissue formation and repair. Advances in polymer technology and a better understanding of naturally derived scaffolds have given rise to novel biomaterials with an increasing ability to recapitulate native tissue environments. This coupled with advances in the understanding of stem cell biology and technology has opened new avenues for regenerative strategies with true clinical translatability. These advances have provided the impetus to develop alternative approaches to enhance the fracture repair process. We provide an update on these advances, with a focus on the development of novel biomimetic approaches for bone regeneration and their translational potential

Investigation of fiber/matrix adhesion: test speed and specimen shape effects in the cylinder test

The cylinder test, developed from the microdroplet test, was adapted to assess the interfacial adhesion strength between fiber and matrix. The sensitivity of cylinder test to pull-out speed and specimen geometry was measured. It was established that the effect of test speed can be described as a superposition of two opposite, simultaneous effects which have been modeled mathematically by fitting two parameter Weibull curves on the measured datas. Effects of the cylinder size and its geometrical relation on the measured strength values have been analyzed by finite element method. It was concluded that the geometry has a direct influence on the stress formation. Based on the results achieved, recommendations were given on how to perform the novel single fiber cylinder test

Men's experiences of middle-age: an interpretative phenomenological analysis

Middle-age is distinctive in both the quantity of stressors experienced and their nature, so is an important area of study. This study used semi-structured e-mail interviews to investigate how a group of nine Caucasian, middle-class, heterosexual men aged between 45 and 55 years made sense of ageing and middle-age. An Interpretative Phenomenological Analysis approach was employed. Analysis of the accounts indicated four superordinate themes: (1) feelings of being trapped in between post-industrial and contemporaneous gender ideals, (2) mind over body, and the disregard of the metrosexual body ideology, (3) fatherhood, being busy, and lost opportunities, (4) holistic and inward self-awareness. Future studies are needed to enable an understanding of middle-aged men's experiences of distress associated with ageing, and to investigate whether this is associated with the progress of long-term physical and mental conditions at midlife

Feedup, feedback, and feedforward in curve mid-air 3D gestures

Issuing a mid-air gesture in a three-dimensional space intrinsically suffers for the lack of explicit direct representation of the gesture with which guidance and feedback can be offered. To address this challenge, we decompose the feedback problem into three components: feedup to constantly represent the goal of the gestural task, feedback to respond to what the end user already did related to the initial goal, and feedforward to modify the representation towards the ultimate goal before terminating the gesture production. We exemplify these three components with case studies representing three levels of complexity of Curve Mid-Air 3D Gestures produced in three environments

Effets de l'ozone sur quelques peuplements forestiers du réseau RENECOFOR

Depuis 2001, le GIEFS et l'ONF s'associent pour repérer la présence de symptômes d'ozone sur une quarantaine de placettes forestières du réseau RENECOFOR, en France. Cet article présente les résultats des observations menées entre 2001 et 2005 sur les placettes des régions méditerranéennes. Les dégâts d'ozone ont été repérés sur l'ensemble des sites de l'étude

Prognostic Implications of Lymph Node Yield and Lymph Node Ratio in Papillary Thyroid Carcinoma

<p>Background: The lymph node yield (LNY) and the lymph node ratio (LNR) have been shown to be important prognostic factors in oral, colon, and gastric cancers. The role of the LNY and LNR in papillary thyroid cancer (PTC) is unclear. The aims of this study were to determine if a high LNR and a low LNY decrease disease-free survival rates. This study further aimed to determine an optimum nodal yield.</p><p>Methods: A retrospective analysis was conducted of 198 patients with PTC undergoing total thyroidectomy with neck dissection between 1987 and 2011. The LNY and LNR were adjusted by relevant covariates in a multivariate Cox regression analysis with Andersen-Gill extension.</p><p>Results: The LNR was associated with a decrease in disease-free survival (hazard ratio 3.2 [95% confidence interval 1.4-7.3], p = 0.005). Patients with an LNR of 0.30 or higher had a 3.4 times higher risk of persistent or recurrent disease compared with patients with an LNR of 0.00 ([95% confidence interval 1.1-10.5], p = 0.031). Conversely, patients with an LNR of 0.11 or lower had an 80% chance of remaining disease free during 5 years of follow-up. The LNY showed no significant independent effect and an optimum nodal yield was not determined.</p><p>Conclusions: The LNR is an important independent prognostic factor in PTC and can be used in conjunction with existing staging systems. A clinical relevant cut-off point of 0.3 (one positive lymph node out of three total) is proposed. No prognostic implications for LNY were identified.</p>

Screening for the loss of protective sensation in people without a history of diabetic foot ulceration: Validation of two simple tests in India

The ability of the Ipswich touch test (IpTT) and VibratipTM to detect loss of protective sensation (LOPS) was tested against a neurothesiometer in an outpatient diabetic population without a history for ulceration. Our results support the use of the IpTT as a screening tool for LOPS, but not of VibratipTM

Saturation of optical absorption in CdS single crystals

The absorption saturation of CdS single crystals was investigated in the Urbach region. It was shown that the threshold behaviour of the absorption coefficient is caused by recharging of the shallow acceptors, and the absorption edge has exponential character both at low and high pumping intensities. The calculation method of nonlinear transmission dependencies was proposed. Using the known formulae one can minimize the value of root mean square deviation of the measured data from the calculated ones in the whole region of the light intensities