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1.
Sequence analyses of the complete brown bear, Ursus arctos, mitochondrial DNA (mtDNA) genome have detected scattered single nucleotide polymorphisms (SNPs) that define distinct mtDNA haplogroups in phylogeographical studies. The degraded DNA in historical samples, such as stuffed or excavated specimens, however, is often not suitable for sequence analyses. To address this problem, we developed an amplified product length polymorphism (APLP) analysis for mtDNA‐haplogrouping U. arctos specimens by detecting haplogroup‐specific SNPs. We verified the validity and utility of this method by analysing up to 170‐year‐old skin samples from U. arctos specimens collected widely across continental Eurasia. We detected some of the same haplogroups as those occurring in eastern Hokkaido (Japan) and eastern Alaska in continental Eurasia (the Altai and the Caucasus). Our results show that U. arctos in eastern Hokkaido and eastern Alaska descended from a common ancestor in continental Eurasia, and suggest that U. arctos occupied several refugia in southern Asia during the Last Glacial Maximum. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 111 , 627–635.  相似文献   
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As recently announced by the American Society for Reproductive Medicine (ASRM), human ovarian tissue cryopreservation is an established option for fertility preservation in prepubertal girls and young women undergoing gonadotoxic treatments for cancer as well as some autoimmune diseases. Proper ovarian tissue assessment before and after cryopreservation is essential to increase success rates. Ovarian fragments from 16 patients were divided into small pieces in form of cortex with medulla, and randomly divided into the following two groups. Pieces of Group 1 (n?=?16) were frozen immediately after operation, thawed and just after thawing their quality was analyzed. Group 2 pieces (n?=?16) after operation were cooled to 5 °C for 24 h, then frozen after 24 h pre-cooling to 5 °C, thawed and just after thawing their quality was analyzed. The effectiveness of the pre-freezing cooling of tissue was evaluated by the development and viability of follicles (Calcein-AM and Propidium Iodide) using complex object parametric analyzer and sorter machine (COPAS). Positive effect of cooling of cells to low supra-zero temperatures on their future development after re-warming has been observed. New flow cytometry- technique is suitable for the evaluation and sorting of cryopreserved whole human whole intact ovarian fragments. Long time (24 h) cooling of ovarian tissue to 5 °C before cryopreservation has a trend of a cell viability increasing.

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Background aimsAcute pyelonephritis is one of the most frequent infectious diseases of the urinary tract and a leading cause of kidney failure worldwide. One strategy for modulating excessive inflammatory responses in pyelonephritis is administration of mesenchymal multipotent stromal cells (MMSCs).MethodsThe putative protective effect of injection of MMSCs against experimental acute pyelonephritis was examined. We used in vivo experimental model of APN where bacteria are introduced in the bladder of rat. Three days after, intravenous injection of MMSCs was done. On the 7th day blood samples and kidneys were taken for further analysis.ResultsWe found obvious signs of oxidative stress and inflammation in the kidney in acute pyelonephritis in rats. Particularly, pro-inflammatory cytokine tumor necrosis factor-α levels, malondialdehyde, nitrite and myeloperoxidase activity were significantly increased. Histologic evaluation revealed numerous attributes of inflammation and tissue damage in the kidney. Treatment with MMSCs caused a remarkable decrease of all of these pathologic signs in renal tissue. Also, activated leukocytes induced pre-conditioning-like signaling in MMSCs. We showed alterations of expression or activity of inducible nitric oxide synthase, transforming growth factor-β, matrix metalloproteinase-2 and glycogen synthase kinase-3β, which could mediate immunomodulation and protective effects of MMSCs. This signaling could be characterized as inflammatory pre-conditioning.ConclusionsThe beneficial capacity of MMSCs to alleviate renal inflammation was more pronounced when pre-conditioned MMSCs were used. This approach could be used to prime MMSCs with different inflammatory modulators to enhance their engraftment and function in an immunoprotected fashion.  相似文献   
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World Journal of Microbiology and Biotechnology - Derived from RNA, 5?-ribonucleotides, especially Inosine-5?-monophosphate (IMP) and guanosine-5?-monophosphate (GMP), can enhance...  相似文献   
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Harris CD  Ermak G  Davies KJ 《The FEBS journal》2007,274(7):1715-1724
At least two different isoforms of RCAN1 mRNA are expressed in neuronal cells in normal human brain. Although RCAN1 mRNA is elevated in brain regions affected by Alzheimer's disease, it is not known whether the disease affects neuronal RCAN1, or if other cell types (e.g. astrocytes or microglia) are affected. It is also unknown how many protein isoforms are expressed in human brain and whether RCAN1 protein is overexpressed in Alzheimer's disease. We explored the expression of both RCAN1-1 and RCAN1-4 mRNA isoforms in various cell types in normal and Alzheimer's disease postmortem samples, using the combined technique of immunohistochemistry and in situ hybridization. We found that both exon 1 and exon 4 are predominantly expressed in neuronal cells, and no significant expression of either of the exons was observed in astocytes or microglial cells. This was true in both normal and Alzheimer's disease brain sections. We also demonstrate that RCAN1-1 mRNA levels are approximately two-fold higher in neurons from Alzheimer's disease patients versus non-Alzheimer's disease controls. Using western blotting, we now show that there are three RCAN1 protein isoforms expressed in human brain: RCAN1-1L, RCAN1-1S, and RCAN1-4. We have determined that RCAN1-1L is expressed at twice the level of RCAN1-4, and that there is very minor expression of RCAN1-1S. We also found that the RCAN1-1L protein is overexpressed in Alzheimer's disease patients, whereas RCAN1-4 is not. From these results, we conclude that RCAN1-1 may play a role in Alzheimer's disease, whereas RCAN1-4 may serve another purpose.  相似文献   
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High solar flux is known to diminish photosynthetic growth rates, reducing biomass productivity and lowering disease tolerance. Photosystem II (PSII) of plants is susceptible to photodamage (also known as photoinactivation) in strong light, resulting in severe loss of water oxidation capacity and destruction of the water‐oxidizing complex (WOC). The repair of damaged PSIIs comes at a high energy cost and requires de novo biosynthesis of damaged PSII subunits, reassembly of the WOC inorganic cofactors and membrane remodeling. Employing membrane‐inlet mass spectrometry and O2‐polarography under flashing light conditions, we demonstrate that newly synthesized PSII complexes are far more susceptible to photodamage than are mature PSII complexes. We examined these ‘PSII birth defects’ in barley seedlings and plastids (etiochloroplasts and chloroplasts) isolated at various times during de‐etiolation as chloroplast development begins and matures in synchronization with thylakoid membrane biogenesis and grana membrane formation. We show that the degree of PSII photodamage decreases simultaneously with biogenesis of the PSII turnover efficiency measured by O2‐polarography, and with grana membrane stacking, as determined by electron microscopy. Our data from fluorescence, QB‐inhibitor binding, and thermoluminescence studies indicate that the decline of the high‐light susceptibility of PSII to photodamage is coincident with appearance of electron transfer capability QA?QB during de‐etiolation. This rate depends in turn on the downstream clearing of electrons upon buildup of the complete linear electron transfer chain and the formation of stacked grana membranes capable of longer‐range energy transfer.  相似文献   
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