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Multipotential bone marrow stromal cells have the ability to differentiate along multiple connective tissue lineages including cartilage. In this study, we developed an efficient and reproducible procedure for the isolation of stromal cells from bone marrow aspirates of normal human donors based on the expression of endoglin, a type III receptor of the transforming growth factor-beta (TGF-beta) receptor family. We demonstrate that these cells have the ability of multiple lineage differentiation. Stromal cells represented 2-3% of the total mononuclear cells of the marrow. The cells displayed a fibroblastic colony formation in monolayer culture and maintained similar morphology with passage. Expression of cell surface molecules by flow cytometry displayed a stable phenotype with culture expansion. When cocultured with hematopoietic CD34(+) progenitor cells, stromal cells were able to maintain their ability to support hematopoiesis in vitro. Culture expanded stromal cells were placed in a 3-dimensional matrix of alginate beads and cultured in serum-free media in the presence of TGFbeta-3 for chondrogenic lineage progression. Increased expression of type II collagen messenger RNA was observed in the TGFbeta3 treated cultures. Immunohistochemistry performed on sections of alginate beads detected the presence of type II collagen protein. This isolation procedure for stromal cells and the establishment of the alginate culture system for chondrogenic progression will contribute to the understanding of chondrogenesis and cartilage repair.  相似文献   
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High throughput screening fluorescence polarization assays using G protein-coupled receptors (GPCRs) as targets have been compared using fluorescein and BODIPY TMR-labeled peptides. The red-shifted BODIPY TMR dye exhibits improved assay performance relative to fluorescein due to improvement in both ligand affinity to the GPCRs and assay precision brought about by the higher intensity probe. Furthermore, the red-shifted dye demonstrates an insensitivity to the effects of the highly colored compound tartrazine, which can produce false-negative results for assays conducted with fluorescein as a label.  相似文献   
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Summary.  Bergenia emeiensis C.Y. Wu ex J.T. Pan is illustrated and described. Its relationship to other Himalayan species is discussed, and instructions for its cultivation are given.  相似文献   
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Summary.  Fritillaria karelinii Fisch. ex D.Don ( Liliaceae ) is illustrated. Its relationships with other species and the position of subgenus Rhinopetalum are discussed. Instructions for its cultivation are given.  相似文献   
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Background

Foodborne diseases are globally important, resulting in considerable morbidity and mortality. Parasitic diseases often result in high burdens of disease in low and middle income countries and are frequently transmitted to humans via contaminated food. This study presents the first estimates of the global and regional human disease burden of 10 helminth diseases and toxoplasmosis that may be attributed to contaminated food.

Methods and Findings

Data were abstracted from 16 systematic reviews or similar studies published between 2010 and 2015; from 5 disease data bases accessed in 2015; and from 79 reports, 73 of which have been published since 2000, 4 published between 1995 and 2000 and 2 published in 1986 and 1981. These included reports from national surveillance systems, journal articles, and national estimates of foodborne diseases. These data were used to estimate the number of infections, sequelae, deaths, and Disability Adjusted Life Years (DALYs), by age and region for 2010. These parasitic diseases, resulted in 48.4 million cases (95% Uncertainty intervals [UI] of 43.4–79.0 million) and 59,724 (95% UI 48,017–83,616) deaths annually resulting in 8.78 million (95% UI 7.62–12.51 million) DALYs. We estimated that 48% (95% UI 38%-56%) of cases of these parasitic diseases were foodborne, resulting in 76% (95% UI 65%-81%) of the DALYs attributable to these diseases. Overall, foodborne parasitic disease, excluding enteric protozoa, caused an estimated 23.2 million (95% UI 18.2–38.1 million) cases and 45,927 (95% UI 34,763–59,933) deaths annually resulting in an estimated 6.64 million (95% UI 5.61–8.41 million) DALYs. Foodborne Ascaris infection (12.3 million cases, 95% UI 8.29–22.0 million) and foodborne toxoplasmosis (10.3 million cases, 95% UI 7.40–14.9 million) were the most common foodborne parasitic diseases. Human cysticercosis with 2.78 million DALYs (95% UI 2.14–3.61 million), foodborne trematodosis with 2.02 million DALYs (95% UI 1.65–2.48 million) and foodborne toxoplasmosis with 825,000 DALYs (95% UI 561,000–1.26 million) resulted in the highest burdens in terms of DALYs, mainly due to years lived with disability. Foodborne enteric protozoa, reported elsewhere, resulted in an additional 67.2 million illnesses or 492,000 DALYs. Major limitations of our study include often substantial data gaps that had to be filled by imputation and suffer from the uncertainties that surround such models. Due to resource limitations it was also not possible to consider all potentially foodborne parasites (for example Trypanosoma cruzi).

Conclusions

Parasites are frequently transmitted to humans through contaminated food. These estimates represent an important step forward in understanding the impact of foodborne diseases globally and regionally. The disease burden due to most foodborne parasites is highly focal and results in significant morbidity and mortality among vulnerable populations.  相似文献   
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