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Minipigs are a recommended large animal model for preclinical testing of human orthopedic implants. Mesenchymal stem cells (MSCs) are the key repair cells in bone healing and implant osseointegration, but the osteogenic capacity of minipig MSCs is incompletely known. The aim of this study was to isolate and characterize minipig bone marrow (BM) and peripheral blood (PB) MSCs in comparison to human BM‐MSCs. BM sample was aspirated from posterior iliac crest of five male Göttingen minipigs (age 15 ± 1 months). PB sample was drawn for isolation of circulating MSCs. MSCs were selected by plastic‐adherence as originally described by Friedenstein. Cell morphology, colony formation, proliferation, surface marker expression, and differentiation were examined. Human BM‐MSCs were isolated and cultured from adult fracture patients (n = 13, age 19–60 years) using identical techniques. MSCs were found in all minipig BM samples, but no circulating MSCs could be detected. Minipig BM‐MSCs had similar morphology, proliferation, and colony formation capacities as human BM‐MSCs. Unexpectedly, minipig BM‐MSCs had a significantly lower ability than human BM‐MSCs to form differentiated and functional osteoblasts. This observation emphasizes the need for species‐specific optimization of MSC culture protocol before direct systematic comparison of MSCs between human and various preclinical large animal models can be made. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 30:1019–1025, 2012  相似文献   
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This paper describes occupational health nurses' and school staff members' experiences of work ability maintenance carried out at schools and the development of ideas to promote the collaboration between occupational health care and school community and to enhance work ability maintenance. The data were collected in a baseline situation of an action research project to further plan and develop activities. The data were analysed by inductive content analysis. According to the results, school community staff members' work ability maintenance focused on the employee, the school community, school work and the working conditions as well as professional competence. The practical actions involved some individual and school-specific variation, focusing on actions to maintain individual and physical work ability. It seems that the collaboration between the school community and occupational health service for work ability maintenance took place at the individual level, but an obvious need for more structural collaboration emerged by several suggestions made by the participants (e.g. better information exchange between the school and occupational health care, improved collaboration between the school staff and the co-operative partners). The progress in collaboration may lead towards spontaneous collaboration, in which case both actors have the same target and work in a planned, continuous and natural way to ensure work ability maintenance in the school community.  相似文献   
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Stroke is a major cause of epilepsy, but the molecular mechanisms underlying post-stroke epileptogenesis are unknown. The expression of cystatin C, a cysteine protease inhibitor, is increased in the hippocampus during status epilepticus (SE)-induced epileptogenesis, and regulates both cell death and birth. To test the hypothesis that increased cystatin C expression represents a common molecular alteration induced by epileptogenic brain insults, we investigated the time course, cellular localization, and association of cystatin C expression with neuronal damage during post-stroke epileptogenesis. Stroke was induced with photothrombosis, which leads to epilepsy in approximately 20-30% of rats. Cystatin C expression was increased in the CA1 area of the hippocampus 4 days after photothrombosis, when the diameter of the lesion was the largest. Double-labeling and confocal analysis indicated that cystatin C was expressed in astrocytes and microglia. Unlike after SE, cystatin C expression did not change in the dentate gyrus. Also, increased cystatin C expression was not associated with neurodegeneration, which was demonstrated as an absence of Fluoro Jade B-positive cells in adjacent sections. The present study provides evidence that cystatin C may be involved in cellular alterations that occur after an epileptogenic insult, not only after SE but also after photothrombotic stroke.  相似文献   
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Pneumococcal neuraminidase, NanA, is a pneumococcal vaccine candidate. Prior culture-confirmed pneumococcal contacts were shown to induce serum anti-NanA antibodies during the first 2 years of life. The antibody concentrations at neither 12 nor 18 months were significantly associated with the risk of subsequent pneumococcal carriage or acute otitis media.  相似文献   
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Recent data has demonstrated that mutations in PINK1, encoding PTEN-induced kinase 1, are a cause of early onset recessive parkinsonism (PARK6 locus). Common variability in genes implicated in hereditary forms of parkinsonism may be a predisposing factor in sporadic Parkinson's disease (PD). We analyzed whether six different genetic variants within and surrounding PINK1 contribute to the risk of sporadic PD in a Finnish case-control series. Our results indicate that this gene does not play a major role in the genetic predisposition to PD in this population.  相似文献   
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The aims of this study were to examine the prevalence, co-occurrence, and psychosocial determinants of self-perceived headache, abdominal pain, and sleep problems among adolescents. The adolescents from two cities in Finland (n?=?2,215, 90.9% of the target population) attending 7th and 9th grade (age range 13-18?years) participated in the cross-sectional survey inquiring about frequency of headache, abdominal pain, sleep problems, and psychosocial difficulties. The 6-month prevalence of weekly headache was 13%, abdominal pain 6%, and sleep problems 27%. All three symptoms were strongly associated with each other. Of the adolescents suffering from one symptom, 32% reported one co-occurring symptom and 17% two co-occurring symptoms. In the multivariate analysis, female gender, experience of psychological difficulties, emotional symptoms, smoking, victimization, and feeling not cared about by teachers were independently associated with all the individual symptoms, as well as an increasing number of symptoms. Sleep problems were associated with older age and peer and alcohol problems. Abdominal pain was associated with conduct problems, and both headache and abdominal pain were linked with immigration background. An increasing number of symptoms was associated with older age, having a chronic illness, and conduct and alcohol problems. Adolescents' headache, abdominal pain and sleep problems were common and often co-occurred. An increasing frequency of each symptom and number of symptoms were associated with psychosocial factors in a similar way. Screening for psychiatric symptoms, substance use, victimization and difficulties with teachers should be included in the assessment of adolescents who suffer from recurrent headache, abdominal pain or sleep problems.  相似文献   
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International Journal of Mental Health and Addiction - Excessive digital gaming can have unfavorable effects on gamers’ well-being and everyday functioning. The aims of this study were to...  相似文献   
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