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排序方式: 共有1113条查询结果,搜索用时 18 毫秒
41.
Henrik Gislason Jeremy Collie Brian R. MacKenzie Anders Nielsen Maria de Fatima Borges Teresa Bottari Corina Chaves Andrey V. Dolgov Jakov Dul
i Daniel Duplisea Heino O. Fock Didier Gascuel Luís Gil de Sola Jan Geert Hiddink Remment ter Hofstede Igor Isajlovi Jnas Pll Jonasson Ole Jrgensen Kristjn Kristinsson Gudrun Marteinsdottir Hicham Masski Sanja Mati‐Skoko Mark R. Payne Melita Peharda Jakup Reinert Jn Slmundsson Cristina Silva Lilja Stefansdottir Francisco Velasco Nedo Vrgo
《Global Ecology and Biogeography》2020,29(5):842-856
42.
Shazmeen Aslam Irfan Khan Fatima Jameel Midhat Batool Zaidi Asmat Salim 《World journal of stem cells》2020,12(12):1652-1666
BACKGROUNDImpaired wound healing can be associated with different pathological states. Burn wounds are the most common and detrimental injuries and remain a major health issue worldwide. Mesenchymal stem cells (MSCs) possess the ability to regenerate tissues by secreting factors involved in promoting cell migration, proliferation and differentiation, while suppressing immune reactions. Preconditioning of MSCs with small molecules having cytoprotective properties can enhance the potential of these cells for their use in cell-based therapeutics.AIMTo enhance the therapeutic potential of MSCs by preconditioning them with isorhamnetin for second degree burn wounds in rats.METHODSHuman umbilical cord MSCs (hU-MSCs) were isolated and characterized by surface markers, CD105, vimentin and CD90. For preconditioning, hU-MSCs were treated with isorhamnetin after selection of the optimized concentration (5 µmol/L) by cytotoxicity analysis. The migration potential of these MSCs was analyzed by the in vitro scratch assay. The healing potential of normal, and preconditioned hU-MSCs was compared by transplanting these MSCs in a rat model of a second degree burn wound. Normal, and preconditioned MSCs (IH + MSCs) were transplanted after 72 h of burn injury and observed for 2 wk. Histological and gene expression analyses were performed on day 7 and 14 after cell transplantation to determine complete wound healing.RESULTSThe scratch assay analysis showed a significant reduction in the scratch area in the case of IH + MSCs compared to the normal untreated MSCs at 24 h, while complete closure of the scratch area was observed at 48 h. Histological analysis showed reduced inflammation, completely remodeled epidermis and dermis without scar formation and regeneration of hair follicles in the group that received IH + MSCs. Gene expression analysis was time dependent and more pronounced in the case of IH + MSCs. Interleukin (IL)-1β, IL-6 and Bcl-2 associated X genes showed significant downregulation, while transforming growth factor β, vascular endothelial growth factor, Bcl-2 and matrix metallopeptidase 9 showed significant upregulation compared to the burn wound, showing increased angiogenesis and reduced inflammation and apoptosis.CONCLUSIONPreconditioning of hU-MSCs with isorhamnetin decreases wound progression by reducing inflammation, and improving tissue architecture and wound healing. The study outcome is expected to lead to an improved cell-based therapeutic approach for burn wounds. 相似文献
43.
Guilherme Razzera Gabriele Gadermaier Marcius S. Almeida Fatima Ferreira Fabio C. L. Almeida Ana Paula Valente 《Biomolecular NMR assignments》2009,3(1):103-106
Art v 1 is the major allergen of Artemisia vulgaris. The IgE raised against Art v 1 not only can cross-react with other proteins from the Asteraceae family members but also with components of various forms of food. Art v 1 is an important target for immunotherapy strategies,
including vaccination with hypoallergenic derivatives or chimeras. We report the 1H, 13C, and 15N resonance assignments of the recombinant Art v 1 and identification of secondary structures based on 13C chemical shifts. 相似文献
44.
Vladimir G. Onipchenko Mikhail I. Makarov Richard S. P. van Logtestijn Viktor B. Ivanov Assem A. Akhmetzhanova Dzhamal K. Tekeev Anton A. Ermak Fatima S. Salpagarova Anna D. Kozhevnikova Johannes H. C. Cornelissen 《Ecology letters》2009,12(8):758-764
The evolution of plants has yielded a wealth of adaptations for the acquisition of key mineral nutrients. These include the structure, physiology and positioning of root systems. We report the discovery of specialized snow roots as a plant strategy to cope with the very short season for nutrient uptake and growth in alpine snow-beds, i.e. patches in the landscape that remain snow-covered well into the summer. We provide anatomical, chemical and experimental 15 N isotope tracking evidence that the Caucasian snow-bed plant Corydalis conorhiza forms extensive networks of specialized above-ground roots, which grow against gravity to acquire nitrogen directly from within snow packs. Snow roots capture nitrogen that would otherwise partly run off down-slope over a frozen surface, thereby helping to nourish these alpine ecosystems. Climate warming is changing and will change mountain snow regimes, while large-scale anthropogenic N deposition has increased snow N contents. These global changes are likely to impact on the distribution, abundance and functional significance of snow roots. 相似文献
45.
Michael J. Smietana Fatima N. Syed-Picard Jinjin Ma Tatiana Kostrominova Ellen M. Arruda Lisa M. Larkin 《In vitro cellular & developmental biology. Animal》2009,45(9):512-522
Our laboratory has previously developed scaffoldless engineered bone constructs (EBC). Bone marrow stromal cells (BMSC) were
harvested from rat femur and cultured in medium that induced osteogenic differentiation. After reaching confluence, the monolayer
of cells contracted around two constraint points forming a cylinder. EBCs were placed in small diameter (0.5905 × 0.0625 in.)
or large diameter (0.5905 × 0.125 in.) silicone tubing and implanted intramuscularly in the hind limb of a rat. Bone mineral
content (BMC) of the EBC was analyzed before implantation and at 1 and 2 mo following implantation and compared to that of
native femur bone at different stages of development. Negligible BMC was observed in E-20 femur or EBCs prior to implantation.
One-month implantation in both small and large tubing increased BMC in the EBC. BMC of EBC from large tubing was greater than
in 14 d rat neonatal femurs, but was 2% and 3% of BMC content in adult bone after 1 and 2 mo of implantation, respectively.
Alizarine Red and osteopontin staining of the EBCs before and after implantation confirmed increased bone mineralization in
the implanted EBCs. Implanted EBCs also had extensive vascularization. Our data suggest that BMSC can be successfully used
for the generation of scaffoldless EBC, and this model can be potentially used for the generation of autologous bone transplants
in humans. 相似文献
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49.
Daria Grafodatskaya Barian HY Chung Darci T Butcher Andrei L Turinsky Sarah J Goodman Sana Choufani Yi-An Chen Youliang Lou Chunhua Zhao Rageen Rajendram Fatima E Abidi Cindy Skinner James Stavropoulos Carolyn A Bondy Jill Hamilton Shoshana Wodak Stephen W Scherer Charles E Schwartz Rosanna Weksberg 《BMC medical genomics》2013,6(1):1-18
Background
A number of neurodevelopmental syndromes are caused by mutations in genes encoding proteins that normally function in epigenetic regulation. Identification of epigenetic alterations occurring in these disorders could shed light on molecular pathways relevant to neurodevelopment.Results
Using a genome-wide approach, we identified genes with significant loss of DNA methylation in blood of males with intellectual disability and mutations in the X-linked KDM5C gene, encoding a histone H3 lysine 4 demethylase, in comparison to age/sex matched controls. Loss of DNA methylation in such individuals is consistent with known interactions between DNA methylation and H3 lysine 4 methylation. Further, loss of DNA methylation at the promoters of the three top candidate genes FBXL5, SCMH1, CACYBP was not observed in more than 900 population controls. We also found that DNA methylation at these three genes in blood correlated with dosage of KDM5C and its Y-linked homologue KDM5D. In addition, parallel sex-specific DNA methylation profiles in brain samples from control males and females were observed at FBXL5 and CACYBP.Conclusions
We have, for the first time, identified epigenetic alterations in patient samples carrying a mutation in a gene involved in the regulation of histone modifications. These data support the concept that DNA methylation and H3 lysine 4 methylation are functionally interdependent. The data provide new insights into the molecular pathogenesis of intellectual disability. Further, our data suggest that some DNA methylation marks identified in blood can serve as biomarkers of epigenetic status in the brain. 相似文献50.
Fatima Kasbi Chadli Hassane Nazih Michel Krempf Patrick Nguyen Khadija Ouguerram 《PloS one》2013,8(4)
The aim of this study was to investigate macrophage reverse cholesterol transport (RCT) in hamster, a CETP-expressing species, fed omega 3 fatty acids (ω3PUFA) supplemented high fat diet (HFD). Three groups of hamsters (n = 6/group) were studied for 20 weeks: 1) control diet: Control, 2) HFD group: HF and 3) HFD group supplemented with ω3PUFA (EPA and DHA): HFω3. In vivo macrophage-to-feces RCT was assessed after an intraperitoneal injection of 3H-cholesterol-labelled hamster primary macrophages.Compared to Control, HF presented significant (p<0.05) increase in body weight, plasma TG (p<0.01) and cholesterol (p<0.001) with an increase in VLDL TG and in VLDL and LDL cholesterol (p<0.001).Compared to HF, HFω3 presented significant decrease in body weight. HFω3 showed less plasma TG (p<0.001) and cholesterol (p<0.001) related to a decrease in VLDL TG and HDL cholesterol respectively and higher LCAT activity (p<0.05) compared to HF. HFω3 showed a higher fecal bile acid excretion (p<0.05) compared to Control and HF groups and higher fecal cholesterol excretion (p<0.05) compared to HF. This increase was related to higher gene expression of ABCG5, ABCA1 and SR-B1 in HFω3 compared to Control and HF groups (<0.05) and in ABCG1 and CYP7A1 compared to HF group (p<0.05). A higher plasma efflux capacity was also measured in HFω3 using 3H- cholesterol labeled Fu5AH cells.In conclusion, EPA and DHA supplementation improved macrophage to feces reverse cholesterol transport in hamster fed HFD. This change was related to the higher cholesterol and fecal bile acids excretion and to the activation of major genes involved in RCT. 相似文献