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1.
Autologous periosteal transplantation (without chondrocyte cell transplantation) for treating traumatic articular cartilage defects of the patella gives pain relief in uncontrolled clinical studies. To study the whole transplanted area macroscopically and microscopically, animal studies are motivated. In this pilot study, we reproduce the surgical technique for periosteum transplantation on human patella to a rabbit model. A full-thickness cartilage defect of the whole patella was created in eight adult female rabbits. The defect was treated with autologous periosteal transplantation. After surgery, the rabbits were allowed free activity. This is the difference compared to the treatment in humans, where our group uses CPM for 5 days and non-weight-bearing for 12 weeks. After 21 weeks, there was a diffuse synovitis in all transplanted knees, and in five of eight knees there were signs of osteoarthritis in the patello-femoral joint. Histologically, in three animals, small islands of hyaline cartilage surrounded by fibrocartilage were seen in the transplanted area. In the other five animals, fibrocartilage was the predominant tissue. In contrast to previous experimental studies using a rabbit model, we did not achieve hyaline cartilage resurfacing.  相似文献   
2.
Recent reports have revealed an involvement of microglial cells in dopaminergic neurodegeneration. In the present study, we tested the hypothesis that interleukin-18 (IL-18) plays a role in the microglial activation. The present study investigated microglial activation and dopaminergic neurodegeneration in substantia nigra pars compacta (SNpc) following 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) treatment in wild type (WT) and IL-18 knockout (KO) mice. The number of dopaminergic neuron loss in WT mice was significantly decreased 7 days after MPTP treatment compared with IL-18 KO mice. In WT mice microglial activation occurred in the SN at 1 day after MPTP treatment, progressively increased within the SNpc until 7 days post MPTP, and subsided by 14 days. In contrast, in IL-18 KO mice microglial activation occurred in the SN at 1 day post-MPTP, and decreased by 7 days, earlier than in WT mice. The lesser microglial activation and dopaminergic neurodegeneration in the SNpc following MPTP treatment in WT indicates the possibility that IL-18 may participate in microglial activation and dopaminergic neurodegeneration.  相似文献   
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Abstract

Discrepancy in leg length does frequently occur as a side effect of total hip arthroplasty and may lead to reduced patient satisfaction as well as injury in the sequalae. It is consequently important to reduce leg length discrepancy where-ever technically possible. This may be achieved by recording precise intraoperative measurements and using different sized implanted components. The aim of the given study was to improve the accuracy of a previously validated optic measurement system (OMS) to reduce leg length discrepancy. This pre-existing OMS was first trialled and based on these preliminary findings developed further. Using this improved system, measurements were taken in models and cadavers. Inter observer reliability of the improved OMS was assessed. The system is introduced in the given technical feasibility study. Its accuracy was greater in the model setup (swivel joint: 772.7?±?1.5?mm; ball joint: 770.0?±?3.7?mm; reference: 772?mm) compared to the trial using cadaveric tissues (588.8?±?5.7?mm; reference: 586?mm). Results of two examiners were similar. The third one measured significantly shorter values (p=.011). The results of the measurements with the OMS indicate that a significant increase in accuracy (p?=?2.076×10?6) has been achieved compared to the previously reported system, however, a further improvement to measurement accuracy is necessary for this to be applied clinically.  相似文献   
5.
Summary Integrated surface electromyograms of the three superficial parts of the quadriceps and isokinetic knee extensor maximum torque and power production were recorded simultaneously and at different angular velocities in both legs in 11 male subjects with unilateral tear of the anterior cruciate ligament. The cross-sectional area (CSA) of the thigh and its muscular components were measured by computerized tomography. The principal findings were a small but significant decrease in quadriceps CSA on the affected side; a decreased active, but not passive, range of movement; decreased mechanical output, whether or not corrected for differences in CSA; and decreased electrornyographic activity — particularly in rectus femoris. These findings suggest that the reason for the decreased maximum and total knee extensor performance seen in these patients is a change in knee joint receptor afferent inflow.  相似文献   
6.
Drapkin R  Crum CP  Hecht JL 《Human pathology》2004,35(8):1014-1021
EpCAM, epithelial membrane antigen (EMA)-mucin 1 (MUC1), mesothelin, and CD9 have been reported to be overexpressed at the RNA level in ovarian carcinomas. By using immunohistochemistry, we profiled the protein expression of these gene products in ovarian carcinoma tissues and compared them with benign ovarian surface epithelium (OSE) and cortical inclusion cysts (CICs). Immunoreactivity for EMA and calretinin were used to define epithelial and mesothelial differentiation in nontumor tissues, respectively. Papillary serous (n = 16) and endometrioid (n = 10) tumors were immunopositive for EMA/MUC1 (100%), mesothelin (75% and 30%, respectively), CD9 (88% and 90%, respectively), and EpCAM (100%). All ovarian carcinomas and carcinoma cell lines tested were negative for calretinin. In nonneoplastic ovary, both OSE and CICs ranged from flat-to-cuboidal to stratified and ciliated in appearance. OSE with a cuboidal morphology had a similar immunoreactivity as omental peritoneum, expressing calretinin, mesothelin, and CD9. In contrast, CICs with stratified and ciliated epithelium show expression patterns similar to those in fallopian tubes. They frequently expressed EMA, EpCAM, mesothelin, and CD9. This immunophenotype is preserved in ovarian carcinomas, suggesting that Müllerian metaplasia signals the acquisition of these markers and that their expression is maintained in ovarian carcinomas that originate from this epithelium.  相似文献   
7.
Depression and vitamin D deficiency are major public health problems. The existing literature indicates the complex relationship between depression and vitamin D. The purpose of this study was to examine whether this relationship is moderated or mediated by inflammation. A community sample (n = 7162) from the LIFE-Adult-Study was investigated, for whom depressive symptoms were assessed via the German version of CES-D scale and serum 25-hydroxyvitamin D (25(OH)D) levels and inflammatory markers (IL-6 and CRP levels, WBC count) were quantified. Mediation analyses were performed using Hayes’ PROCESS macro and regression analyses were conducted to test moderation effects. There was a significant negative correlation between CES-D and 25(OH)D, and positive associations between inflammatory markers and CES-D scores. Only WBC partially mediated the association between 25(OH)D levels and depressive symptoms both in a simple mediation model (ab: −0.0042) and a model including covariates (ab: −0.0011). None of the inflammatory markers showed a moderation effect on the association between 25(OH)D levels and depressive symptoms. This present work highlighted the complex relationship between vitamin D, depressive symptoms and inflammation. Future studies are needed to examine the effect of vitamin D supplementation on inflammation and depressive symptomatology for causality assessment.  相似文献   
8.
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Ein Erratum zu dieser Publikation wurde veröffentlicht: https://doi.org/10.1007/s00103-019-02901-5  相似文献   
9.
Objective. To determine possible racial differences in risk factors for coronary heart disease (CHD) in black and white patients with noninsulin‐dependent diabetes mellitus (NIDDM).

Methods: Study of risk factors for coronary heart disease among 308 subjects who met the WHO criteria for NIDDM.

Results. Both black and white patients were found to have a high prevalence of hypertension, obesity, low high density lipoprotein (HDL) cholesterol, low leisure‐time physical activity levels, and an atherogenic dietary profile. Black males were more likely to have hypertension, reported a greater intake of dietary cholesterol, and had lower triglycerides, higher HDL cholesterol levels, a lower CHOL/HDL ratio, and a lower waist to hip ratio (WHR) than white males. Black females had higher mean arterial and diastolic blood pressures, had lower triglycerides, higher HDL cholesterol, a lower CHOL/HDL ratio, a higher subscapular/triceps ratio and lower reported leisure‐time energy expenditure compared to white females. There were no racial differences found for obesity level.

Conclusion. Our results indicate that racial differences in CHD risk factors exist among black and white patients with NIDDM. The complex genetic, sociocultural and environmental interactions involving CHD risk factors that contribute to the development of CHD may eventually provide clues to the etiology of the disease.  相似文献   

10.
PURPOSE: Residents in rural communities in the United States, especially ethnic minority group members, have limited access to primary and specialty health care that is critical for diabetes management. This study examines primary and specialty medical care utilization among a rural, ethnically diverse, older adult population with diabetes. METHODS: Data were drawn from a cross-sectional face-to-face survey of randomly selected African American (n=220), Native American (n=181), and white (n=297) Medicare beneficiaries > or =65 years old with diabetes in 2 rural counties in central North Carolina. Participants were asked about utilization of a primary care doctor and of specialists (nutritionist, diabetes specialist, eye doctor, bladder specialist, kidney specialist, heart specialist, foot specialist) in the past year. FINDINGS: Virtually all respondents (99.0%) reported having a primary care doctor and seeing that doctor in the past year. About 42% reported seeing a doctor for diabetes-related care. On average, participants reported seeing 2 specialists in the past year, and 54% reported i seeing >1 specialist. Few reported seeing a diabetes specialist (5.7%), nutritionist (10.9%), or kidney specialist (17.5%). African Americans were more likely than others to report seeing a foot specialist (P < .01), while men were more likely than women to have seen bladder specialist (P = .02), kidney specialist (P = .001), and heart specialist (P = .004), after adjusting for potential confounders. Predictors of the number of specialists seen include gender, education, poverty status, diabetes medication use, and self-rated health. CONCLUSIONS: These data indicate low utilization of specialty diabetes care providers across ethnic groups and reflect the importance of primary care providers in diabetes care in rural areas.  相似文献   
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