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Autologous cells suffer from limited cell number and senescence during ex vivo expansion for cartilage repair. Here we found that expansion on extracellular matrix (ECM) deposited by fetal synovium-derived stem cells (SDSCs) (FE) was superior to ECM deposited by adult SDSCs (AE) in promoting cell proliferation and chondrogenic potential. Unique proteins in FE might be responsible for the rejuvenation effect of FE while advantageous proteins in AE might contribute to differentiation more than to proliferation. Compared to AE, the lower elasticity of FE yielded expanded adult SDSCs with lower elasticity which could be responsible for the enhancement of chondrogenic and adipogenic differentiation. MAPK and noncanonical Wnt signals were actively involved in ECM-mediated adult SDSC rejuvenation.  相似文献   
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Early non-haematological toxicity of high dose therapy (HDT) and autologous haematopoietic cell transplantation (autoHCT) can be more hazardous in older patients (pts) with comorbidities. The aim of the study was to analyze incidence and grade of the organ-related early complications up to 30 days post-transplant period in elderly lymphoma patients. Between January 2005 and November 2011, 44 consecutive lymphoma pts underwent HDT followed by autoHCT. Median age of pts was 62 years (range 60–67). Conditioning regimens were: BEAM(carmustine, etoposide, cytarabine, melphalan) in 16, melphalan 200 in 22, cytarabine, melphalan or cyclophosphamide – in 6 pts. 32% pts had comorbidities: in 71% cardiovascular. Early non-haematologic complications within 30 days after autoHCT were reported in 84% of pts. The most common events were gastrointestinal (77%): 55% pts had prolonged (more than 7 days) diarrhoea grade III—IV, nausea and vomiting occurred in 40% of pts, 50% of pts demonstrated mucositis (grade III—IV in 34% of pts). Neutropenic fever was reported in 59% of pts with sepsis in 1.9% of pts. Cardiac events occurred in 9% of pts. Median hospitalization was 21 days (range 16—45). One patient died from transplanted related toxicity. HDT resulted in high incidence of non-hematologic toxicity in elderly patients during early post-transplant period. The toxicity of this procedure is acceptable, with mortality rate of only 2% in the elderly transplanted patients. The most common toxicities were: neutropenic fever, gastrointestinal toxicity and cardiac complications  相似文献   
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A recently identified circovirus (family Circoviridae) was detected in 14 zebra finches (Taeniopygia guttata) from seven aviaries and hobbyist breeders using polymerase chain reaction followed by sequencing. Full genome sequences of virus strains from six zebra finches consistently revealed characteristic circoviral genomic features such as a stem-loop structure and two major open reading frames (ORFs) encoding the replication-associated protein and the putative capsid protein. One further ORF encoding a protein of unknown function was additionally identified in all six genomes. Based on full genome nucleotide comparison, zebra finch circovirus was most similar to Finch circovirus originating from a Gouldian finch (Chloebia gouldiae) sharing 78% nucleotide identity. High genetic diversity was detected in the circoviruses from individual zebra finches. Comparison of the six full genome sequences revealed two genetic subgroups, which shared pairwise nucleotide identities between 91.4% and 92.7%. Analyses including partial sequences of the replication-associated protein gene of the zebra finch circovirus strains from all 14 birds supported the existence of two main clusters. Clinical diseases associated with circovirus infection were found in nestlings, fledglings and adult birds and varied from mild to severe with high mortality caused by secondary infections. Macrorhabdus ornithogaster was the most frequently detected opportunistic pathogen. Feathering disorders were seen in two birds. Lymphocytic depletion of the spleen and leukocytopaenia were detected in individual birds, suggesting immunosuppression and a pathogenesis common to circovirus infections in other birds.  相似文献   
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Blood samples of 50 patients diagnosed for paroxysmal nocturnal haemoglobinuria (PNH) were examined using FLAER screening test for the detection of PNH clone. The results were compared with routine testing using monoclonal antibodies detecting CD59 and CD66b antigens on neutrophils and CD59 on erythrocytes. Assay sensitivity (≥ 0.1%) and PNH clone size analysed using FLAER and anti-CD66b antibodies was fully consistent (R2 = 0.9991) and higher than with anti-CD59 antibodies. Preliminary results indicate that for diagnosis of PNH the FLAER based test is quick, reliable and cost-effective. It might seem that the conventional screening methods could therefore be abandoned. It was found however, that in some cases of abnormal granulocyte population, additional studies should be performed using multiparameter flow cytometry blood cell analysis.  相似文献   
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BACKGROUND: Although several shortterm animal models of stunning and hibernation have been studied extensively, it has been difficult to produce a consistent animal model of chronic hibernation. The aim of the present study was to develop a nonsurgical porcine stent model of coronary stenosis in order to investigate the relationship between chronic dysfunctional myocardium and viability using 2D-echo, dobutamine stress echo (DSE) and positron emission tomography (PET). METHODS AND RESULTS: Focal progressive coronary stenosis was induced by implantation of an oversized stent in the left anterior descending (LAD) and/or circumflex (LCX) coronary artery in a total of 115 pigs, according to various experimental protocols: copper stent in the LAD (group I, n = 5); noncoated stainless steel stent in the LAD combined with balloon overstretch (group II, n = 7); poly(organo)phosphazene-coated stent in the LAD (group III, n = 77); and poly(organo)phosphazene-coated stent in both the LAD and the LCX (group IV, n = 26). Occurrence of left ventricular dysfunction was evaluated weekly by 2D-echo. At the time of left ventricular dysfunction the presence of viable myocardium within the dysfunctional region was investigated with DSE and PET, and confirmed by histology. The degree of coronary artery stenosis was measured by quantitative coronary angiography and morphometry. Severe coronary artery stenosis in the presence of dysfunctional, but viable, myocardium was induced in groups III and IV (47% and 11% of the animals, respectively). CONCLUSIONS: The authors developed a nonsurgical porcine stent model of progressive coronary stenosis using an oversized polymer-coated stent resulting in chronically decreased myocardial function, with residual inotropic reserve and viable myocardium. This condition may arise from repetitive periods of ischemia, or from sustained hypoperfusion, or a combination of these processes eventually leading to myocardial hibernation. (Int J Cardiovasc Intervent 2000; 3: 111-120)  相似文献   
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