181 research outputs found
Stem cell characteristics of human trabecular bone-derived cells
Human trabecular bone-derived cells (HTBs) have been used for many years as osteoblast progenitors. In this study we tested whether HTBs have stem cell characteristics; that is, whether they are pluripotent and able to self-renew. We show that HTBs readily differentiate into osteoblasts, chondrocytes, and adipocytes if subjected to the appropriate differentiating conditions. Importantly, differentiation into these three lineages is maintained in single cell clones derived by limiting dilution, following expansion over more than 20 cumulative population doublings. We conclude that cultures of HTBs are equivalent to cultures of "mesenchymal stem cells" (MSCs) isolated from bone marrow. © 2002 by Elsevier Science Inc. All rights reserved
Effect of a health education intervention on intestinal parasitic infections in Bolivian children
Abstract
Backgrounds
Intestinal parasitic infections (IPI) are a major health issue for children of low- and middle-income countries. Water, sanitation and hygiene (WASH) practices are crucial for preventing IPI. The aim of the study was to evaluate the effects of a school-based health education intervention on handwashing behavior and IPI prevalence in children
Methods
This is a randomized intervention trial in 8 primary schools in rural communities over the course of 3 school years; preliminary results from the first two years of the trial are here presented. Schools were randomly selected and assigned in a 1:1 ratio to intervention or control (no intervention) groups. For each school year, the intervention included 14 school-based educational sessions and 2 skit events, involving children aged 8-12 years. Knowledge, attitude and practice questionnaire and handwashing at key events was assessed at the beginning and end of each school year. IPI prevalence was assessed with repeated cross-sectional parasitology surveys 12 months apart, involving a minimum of 50 children for each school
Results
At baseline, no significant differences between intervention and control schools were present in the proportion of children who washed their hands at key events (7.2% vs 9.3%, p = 0.28), in IPI (79.4% vs 75.3%, p = 0.3) and multiple parasitic infections (MPI) prevalences (47.6 vs. 38.6; p = 0.051). At the end of the second year, the percentage of children who washed their hands at key events was significantly higher in the intervention schools (75.4% vs 12.1%, p < 0.001), and the prevalence of IPI and MPI in the intervention schools were respectively about 25% and 15% lower than in the control schools (respectively, 42.9% vs 67.8%, p < 0.001; 16.1% vs 31.6%, p < 0.001)
Conclusions
A school-based health education intervention could achieve significant changes in hand-washing behaviors and reduction in the prevalence of IPI in children. The third year survey results are needed to confirm these findings
Key messages
An health education intervention on water, sanitation and hygiene (WASH) practices can reduce the risk of IPI infection in children. An health education intervention on water, sanitation and hygiene (WASH) practices could be configured as a sustainable long-term approach to intestinal parasitic infections control in children
Incremental residential densification and urban spatial justice: The case of England between 2001 and 2011
Study of the relation between urban density and social equity has been based mostly upon comparative analysis at the city level. It therefore fails to address variations in intra-urban experience and sheds no light on the process of urban densification. Incremental residential development is particularly poorly recorded and under-researched, yet cumulatively it makes a substantial contribution to the supply of dwellings. The article presents a detailed examination of this form of development in England between 2001 and 2011, and considers its impact on urban spatial justice. We find that the incidence of soft residential densification was very uneven. It had disproportionately large effects on neighbourhoods that were already densely developed and that were characterised by lower income households with access to relatively little residential space. It thus contributed to an increase in the level of inequality in the distribution of residential space, increasing socio-spatial injustice
Air–liquid interface cultures enhance the oxygen supply and trigger the structural and functional differentiation of intestinal porcine epithelial cells (IPEC)
The specific function of the epithelium as critical barrier between the intestinal lumen and the organism’s internal microenvironment is reflected by permanent maintenance of intercellular junctions and cellular polarity. The intestinal epithelial cells are responsible for absorption of nutritional components, facing mechanical stress and a changing oxygen supplementation via blood stream. Oxygen itself can regulate the barrier and the absorptive function of the epithelium. Therefore, we compared the dish cell culture, the transwell-like membrane culture and the oxygen enriched air–liquid interface (ALI) culture. We demonstrated strong influence of the different culture conditions on morphology and function of intestinal porcine epithelial cell lines in vitro. ALI culture resulted in a significant increase in cell number, epithelial cell layer thickness and expression as well as apical localisation of the microvilli-associated protein villin. Remarkable similarities regarding the morphological parameters were observed between ALI cultures and intestinal epithelial cells in vivo. Furthermore, the functional analysis of protein uptake and degradation by the epithelial cells demonstrated the necessity of sufficient oxygen supply as achieved in ALI cultures. Our study is the first report providing marked evidence that optimised oxygen supply using ALI cultures directly affects the morphological differentiation and functional properties of intestinal epithelial cells in vitro
Genetic architecture of the APM1 gene and its influence on adiponectin plasma levels and parameters of the metabolic syndrome in 1,727 healthy Caucasians
Copyright: Copyright 2008 Elsevier B.V., All rights reserved.The associations of the adiponectin (APM1) gene with parameters of the metabolic syndrome are inconsistent. We performed a systematic investigation based on fine-mapped single nucleotide polymorphisms (SNPs) highlighting the genetic architecture and their role in modulating adiponectin plasma concentrations in a particularly healthy population of 1,727 Caucasians avoiding secondary effects from disease processes. Genotyping 53 SNPs (average spacing of 0.7 kb) in the APM1 gene region in 81 Caucasians revealed a two-block linkage disequilibrium (LD) structure and enabled comprehensive tag SNP selection. We found particularly strong associations with adiponectin concentrations for 11 of the 15 tag SNPs in the 1,727 subjects (five P values <0.0001). Haplotype analysis provided a thorough differentiation of adiponectin concentrations with 9 of 17 haplotypes showing significant associations (three P values <0.0001). No significant association was found for any SNP with the parameters of the metabolic syndrome. We observed a two-block LD structure of APM1 pointing toward at least two independent association signals, one including the promoter SNPs and a second spanning the relevant exons. Our data on a large number of healthy subjects suggest a clear modulation of adiponectin concentrations by variants of APM1, which are not merely a concomitant effect in the course of type 2 diabetes or coronary artery disease.publishersversionPeer reviewe
Adipose Tissue Deficiency and Chronic Inflammation in Diabetic Goto-Kakizaki Rats
Type 2 diabetes (T2DM) is a heterogeneous group of diseases that is progressive and involves multiple tissues. Goto-Kakizaki (GK) rats are a polygenic model with elevated blood glucose, peripheral insulin resistance, a non-obese phenotype, and exhibit many degenerative changes observed in human T2DM. As part of a systems analysis of disease progression in this animal model, this study characterized the contribution of adipose tissue to pathophysiology of the disease. We sacrificed subgroups of GK rats and appropriate controls at 4, 8, 12, 16 and 20 weeks of age and carried out a gene array analysis of white adipose tissue. We expanded our physiological analysis of the animals that accompanied our initial gene array study on the livers from these animals. The expanded analysis included adipose tissue weights, HbA1c, additional hormonal profiles, lipid profiles, differential blood cell counts, and food consumption. HbA1c progressively increased in the GK animals. Altered corticosterone, leptin, and adiponectin profiles were also documented in GK animals. Gene array analysis identified 412 genes that were differentially expressed in adipose tissue of GKs relative to controls. The GK animals exhibited an age-specific failure to accumulate body fat despite their relatively higher calorie consumption which was well supported by the altered expression of genes involved in adipogenesis and lipogenesis in the white adipose tissue of these animals, including Fasn, Acly, Kklf9, and Stat3. Systemic inflammation was reflected by chronically elevated white blood cell counts. Furthermore, chronic inflammation in adipose tissue was evident from the differential expression of genes involved in inflammatory responses and activation of natural immunity, including two interferon regulated genes, Ifit and Iipg, as well as MHC class II genes. This study demonstrates an age specific failure to accumulate adipose tissue in the GK rat and the presence of chronic inflammation in adipose tissue from these animals
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