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321.
Kevin Deschamps Giovanni Arnoldo Matricali Philip Roosen Kaat Desloovere Herman Bruyninckx Pieter Spaepen Frank Nobels Jos Tits Mieke Flour Filip Staes 《PloS one》2013,8(11)
Background
The aim of this study was to identify groups of subjects with similar patterns of forefoot loading and verify if specific groups of patients with diabetes could be isolated from non-diabetics.Methodology/Principal Findings
Ninety-seven patients with diabetes and 33 control participants between 45 and 70 years were prospectively recruited in two Belgian Diabetic Foot Clinics. Barefoot plantar pressure measurements were recorded and subsequently analysed using a semi-automatic total mapping technique. Kmeans cluster analysis was applied on relative regional impulses of six forefoot segments in order to pursue a classification for the control group separately, the diabetic group separately and both groups together. Cluster analysis led to identification of three distinct groups when considering only the control group. For the diabetic group, and the computation considering both groups together, four distinct groups were isolated. Compared to the cluster analysis of the control group an additional forefoot loading pattern was identified. This group comprised diabetic feet only. The relevance of the reported clusters was supported by ANOVA statistics indicating significant differences between different regions of interest and different clusters.Conclusion/s Significance
There seems to emerge a new era in diabetic foot medicine which embraces the classification of diabetic patients according to their biomechanical profile. Classification of the plantar pressure distribution has the potential to provide a means to determine mechanical interventions for the prevention and/or treatment of the diabetic foot. 相似文献322.
Objective
To investigate the feasibility, costs and sample representativeness of a recruitment method that used workers with back injuries as the point of entry into diverse working environments.Methods
Workers'' compensation claims were used to randomly sample workers from five heavy industries and to recruit their employers for ergonomic assessments of the injured worker and up to 2 co-workers.Results
The final study sample included 54 workers from the workers’ compensation registry and 72 co-workers. This sample of 126 workers was based on an initial random sample of 822 workers with a compensation claim, or a ratio of 1 recruited worker to approximately 7 sampled workers. The average recruitment cost was CND$262/injured worker and CND$240/participating worksite including co-workers. The sample was representative of the heavy industry workforce, and was successful in recruiting the self-employed (8.2%), workers from small employers (<20 workers, 38.7%), and workers from diverse working environments (49 worksites, 29 worksite types, and 51 occupations).Conclusions
The recruitment rate was low but the cost per participant reasonable and the sample representative of workers in small worksites. Small worksites represent a significant portion of the workforce but are typically underrepresented in occupational research despite having distinct working conditions, exposures and health risks worthy of investigation. 相似文献323.
The ultrastructure of the testes in two representatives of the enigmatic taxon Nemertodermatida was studied using transmission
electron microscopy. Nemertoderma westbladi has paired testes, which are delineated by lining cells. Within each testis, different follicles, each surrounded by a membrane-like
structure, are found. Flagellophora apelti has genuinely follicular testes, consisting of several follicles, each containing a certain stage of spermatogenesis. As
the gametes are not enclosed by a structure that can be called a true gonad, the structure of the testes differs from most
bilaterian animals, but resembles the organization of gametogenic areas of ctenophores. Each stage of spermatogenesis in F. apelti is described, enabling the inference of the origin of the structures seen in mature spermatozoa. The overall structure of
the mature spermatozoa is similar in all nemertodermatids and unique within the Metazoa: an elongated head containing the
nucleus; a middle piece containing an axoneme, mitochondrial derivatives and in F. apelti granular derivatives; and a flagellar tail. 相似文献
324.
325.
Smitha Kumar Ellen Lanckacker Mieke Dentener Ken Bracke Sharen Provoost Katrien De Grove Guy Brusselle Emiel Wouters Tania Maes Guy Joos 《PloS one》2016,11(3)
Background
Although epidemiological studies reveal that cigarette smoke (CS) facilitates the development and exacerbation of allergic asthma, these studies offer limited information on the mechanisms involved. The transmembrane glycoprotein CD44 is involved in cell adhesion and acts as a receptor for hyaluronic acid and osteopontin. We aimed to investigate the role of CD44 in a murine model of CS-facilitated allergic airway inflammation.Methods
Wild type (WT) and CD44 knock-out (KO) mice were exposed simultaneously to house dust mite (HDM) extract and CS. Inflammatory cells, hyaluronic acid (HA) and osteopontin (OPN) levels were measured in bronchoalveolar lavage fluid (BALF). Proinflammatory mediators, goblet cell metaplasia and peribronchial eosinophilia were assessed in lung tissue. T-helper (Th) 1, Th2 and Th17 cytokine production was evaluated in mediastinal lymph node cultures.Results
In WT mice, combined HDM/CS exposure increased the number of inflammatory cells and the levels of HA and OPN in BALF and Th2 cytokine production in mediastinal lymph nodes compared to control groups exposed to phosphate buffered saline (PBS)/CS, HDM/Air or PBS/Air. Furthermore, HDM/CS exposure significantly increased goblet cell metaplasia, peribronchial eosinophilia and inflammatory mediators in the lung. CD44 KO mice exposed to HDM/CS had significantly fewer inflammatory cells in BALF, an attenuated Th2 cytokine production, as well as decreased goblet cells and peribronchial eosinophils compared to WT mice. In contrast, the levels of inflammatory mediators were similar or higher than in WT mice.Conclusion
We demonstrate for the first time that the aggravation of pulmonary inflammation upon combined exposure to allergen and an environmental pollutant is CD44-dependent. Data from this murine model of concomitant exposure to CS and HDM might be of importance for smoking allergic asthmatics. 相似文献326.
327.
Eugenia Migliavacca Christelle Golzio Katrin M?nnik Ian Blumenthal Edwin?C. Oh Louise Harewood Jack A. Kosmicki Maria?Nicla Loviglio Giuliana Giannuzzi Loyse Hippolyte Anne?M. Maillard Ali?Abdullah Alfaiz p. European Consortium Mieke M. van Haelst Joris Andrieux James F. Gusella Mark J. Daly Jacques S. Beckmann Sébastien Jacquemont Michael E. Talkowski Nicholas Katsanis Alexandre Reymond 《American journal of human genetics》2015,96(5):784-796
328.
Javier Muñoz Michael U Musheev Lennart Kester Jan Philipp Junker Nikolai Mischerikow Mandana Arbab Ewart Kuijk Lev Silberstein Peter V Kharchenko Mieke Geens Christof Niehrs Hilde van de Velde Alexander van Oudenaarden Albert JR Heck Niels Geijsen 《EMBO reports》2015,16(7):791-802
Embryonic stem cell (ESC) cultures display a heterogeneous gene expression profile, ranging from a pristine naïve pluripotent state to a primed epiblast state. Addition of inhibitors of GSK3β and MEK (so‐called 2i conditions) pushes ESC cultures toward a more homogeneous naïve pluripotent state, but the molecular underpinnings of this naïve transition are not completely understood. Here, we demonstrate that DAZL, an RNA‐binding protein known to play a key role in germ‐cell development, marks a subpopulation of ESCs that is actively transitioning toward naïve pluripotency. Moreover, DAZL plays an essential role in the active reprogramming of cytosine methylation. We demonstrate that DAZL associates with mRNA of Tet1, a catalyst of 5‐hydroxylation of methyl‐cytosine, and enhances Tet1 mRNA translation. Overexpression of DAZL in heterogeneous ESC cultures results in elevated TET1 protein levels as well as increased global hydroxymethylation. Conversely, null mutation of Dazl severely stunts 2i‐mediated TET1 induction and hydroxymethylation. Our results provide insight into the regulation of the acquisition of naïve pluripotency and demonstrate that DAZL enhances TET1‐mediated cytosine hydroxymethylation in ESCs that are actively reprogramming to a pluripotent ground state. 相似文献
329.
Schutyser E Su Y Yu Y Gouwy M Zaja-Milatovic S Van Damme J Richmond A 《European cytokine network》2007,18(2):59-70
The influence of environmental factors (cytokines, matrix components, serum factors and O(2) level) on expression of receptors for angiogenic versus angiostatic CXC chemokines in human microvascular endothelial cells has not been extensively investigated. Our semi-quantitative RT-PCR analysis demonstrated that TNF-alpha and IFN-gamma repressed CXCR4 mRNA levels in immortalized human microvascular endothelial HMEC-1 cells after 4 h, whereas only TNF-alpha displayed inhibitory activity in primary human microvascular endothelial cells (HMVEC). CXCR4 mRNA expression was not affected by VEGF, GM-CSF, IL-1beta or various basal membrane matrix components, but was significantly up-regulated after serum starvation and/or hypoxic treatment of the microvascular endothelial cells. The alternative CXCL12 receptor, CXCR7/RDC1, was also up-regulated by hypoxia in HMEC-1 cells, although less consistently than CXCR4. Furthermore, hypoxia and serum starvation were required for cell surface display of CXCR4 and CXCL12 induction of ERK activation in HMEC-1 cells. In contrast, CXCR2 and CXCR3 mRNA levels remained, respectively, low and undetectable under all the conditions tested, and surface expression of CXCR2, CXCR3 and CXCR7 on the HMEC- 1 cells could not be demonstrated by FACS. In the human SK-MEL-5 melanoma cell line, CXCR4 mRNA expression was also increased under hypoxic conditions, whereas CXCR2 mRNA levels remained low and levels of CXCR3 and CXCR7 were undetectable. However, immunohistochemical staining of human metastatic melanoma sections demonstrated that CXCR2, CXCR3, CXCR4 and CXCR7 are expressed on tumor cells and, to a lesser extent, on endothelial cells. These results demonstrate that the tumor microenvironment regulates chemokine receptor expression through both cytokine and oxygen levels. 相似文献
330.
Katja J Teerds Federica MF van Dissel-Emiliani Maria P De Miguel Mieke de Boer-Brouwer Lina M Körting Eddy Rijntjes 《Reproductive biology and endocrinology : RB&E》2007,5(1):43-9