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Alginate scaffold has been considered as an appropriate biomaterial for promoting the differentiation of embryonic stem cells toward neuronal cell lineage. We hypothesized that alginate scaffold is suitable for culturing Wharton's jelly mesenchymal stem cells(WJMSCs) and can promote the differentiation of WJMSCs into neuron-like cells. In this study, we cultured WJMSCs in a three-dimensional scaffold fabricated by 0.25% alginate and 50 m M Ca Cl2 in the presence of neurogenic medium containing 10 μM retinoic acid and 20 ng/m L basic fibroblast growth factor. These cells were also cultured in conventional two-dimensional culture condition in the presence of neurogenic medium as controls. After 10 days, immunofluorescence staining was performed for detecting β-tubulin(marker for WJMSCs-differentiated neuron) and CD271(motor neuron marker). β-Tubulin and CD271 expression levels were significantly greater in the WJMSCs cultured in the three-dimensional alginate scaffold than in the conventional two-dimensional culture condition. These findings suggest that three-dimensional alginate scaffold cell culture system can induce neuronal differentiation of WJMSCs effectively.  相似文献   
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Cell therapy using stem cell transplantation against cerebral ischemia has been reported. However, it remains controversial regarding the optimal time for cell transplantation and the transplantation route. Rat models of cerebral ischemia were established by occlusion of the middle cerebral artery. At 1, 12 hours, 1, 3, 5 and 7 days after cerebral ischemia, bone marrow mesenchymal stem cells were injected via the tail vein. At 28 days after cerebral ischemia, rat neurological function was evaluated using a 6-point grading scale and the pathological change of ischemic cerebral tissue was observed by hematoxylin-eosin staining. Under the fluorescence microscope, the migration of bone marrow mesenchymal stem cells was examined by PKH labeling. Caspase-3 activity was measured using spectrophotometry. The optimal neurological function recovery, lowest degree of ischemic cerebral damage, greatest number of bone marrow mesenchymal stem cells migrating to peri-ischemic area, and lowest caspase-3 activity in the ischemic cerebral tissue were observed in rats that underwent bone marrow mesenchymal stem cell transplantation at 12 hours after cerebral ischemia. These findings suggest that 12 hours after cerebral ischemia is the optimal time for tail vein injection of bone marrow mesenchymal stem cell transplantation against cerebral ischemia, and the strongest neuroprotective effect of this cell therapy appears at this time.  相似文献   
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AIM: The healthy ranges for serum alanine aminotransferase (ALT) levels are less well studied. The aim of this study was to define the upper limit of normal (ULN) for serum ALT levels, and to assess factors associated with serum ALT activity in apparently healthy blood donors. METHODS: A total of 1,939 blood donors were included. ALT measurements were performed for all cases using the same laboratory method. Healthy ranges for ALT levels were computed from the population at the lowest risk for liver disease. Univariate and multivariate analyses were performed to evaluate associations between clinical factors and ALT levels. RESULTS: Serum ALT activity was independently associated with body mass index (BMI) and male gender, but not associated with age. Association of ALT with BMI was more prominent in males than in females. Upper limit of normal for non-overweight women (BMI of less than 25) was 34 U/L, and for non-overweight men was 40 U/L. CONCLUSION: Serum ALT is strongly associated with sex and BMI. The normal range of ALT should be defined for male and female separately.  相似文献   
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AIM:The healthy ranges for serum alanine aminotransferase (ALT) levels are less well studied. The aim of this study was to define the upper limit of normal (ULN) for serum ALT levels, and to assess factors associated with serum ALT activity in apparently healthy blood donors.METHODS: A total of 1 939 blood donors were included.ALT measurements were performed for all cases using the same laboratory method. Healthy ranges for ALT levels were computed from the population at the lowest risk for liver disease. Univariate and multivariate analyses were performed to evaluate associations between clinical factors and ALT levels.RESULTS: Serum ALT activity was independently associated with body mass index (BMI) and male gender, but not associated with age. Association of ALT with BMI was more prominent in males than in females. Upper limit of normal for non-overweight women (BMI of less than 25) was 34 U/L,and for non-overweight men was 40 U/L.CONCLUSION: Serum ALT is strongly associated with sex and BMI. The normal range of ALT should be defined for male and female separately.  相似文献   
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Background:

Sarcoidosis is a systemic multi-organ granulomatous disease of unknown etiology that is characterized by the presence of granuloma in various organs. The clinical features of sarcoidosis are heterogeneous but pulmonary involvement is cardinal manifestations. The aim of this study was to determine radiologic, clinical and laboratory findings of patients with sarcoidosis.

Patients and Methods:

In a cross-sectional study, all patients visiting sarcoidosis clinic were enrolled in the study. Computed tomography (CT) scan was obtained and lab exams were obtained from patient and reports were recorded in data sheet.

Results:

Total of 55 patients with sarcoidosis were enrolled in the study. The average of age was 44.6 (range 25-62) years. Thirty-seven patients were male and 18 were female. The most common extra-pulmonary manifestation was arthritis (in 18% of cases) and then lupus pernio (12.8%) and uveitis (10.9%). Bilateral hilar adenopathy and para tracheal lymphadenopathy was observed in 39(70%) and 22 (40%) of patients. Parenchymal nodules (30%), bronchiectasia (25%), ground-glass opacification (18%) were the most common findings. Percentages of patients with dyspnea were 29% and percentages of patients with cough were 21%. Among abnormal lab tests, high urine calcium (Ca) were positive in 21% and high angiotensin-converting enzyme (ACE) in 16% of patients.

Conclusion:

Pulmonary involvements are both fibrosis and granulomatosis and the most common manifestations are parenchymal nodules, bronchiectasia and high-grade fibrosis. The most common extra-pulmonary involvement is arthritis. Lab tests are non-specific and have no correlation with duration or severity of disease.  相似文献   
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BACKGROUND: Hepatitis C virus infection (HCV) is a main health problem in end-stage renal disease (ESRD) patients. The effect of pretransplant HCV infection on survival among ESRD patients who have undergone renal transplantation is controversial. We report the results of a large monocenter study that evaluated the effect of hepatitis C on the patient, and on graft survival in renal-transplanted patients who received living donated allograft. METHODS: A historical cohort study, we investigated all 1006 patients who received a living kidney transplant at Baghiatollah Medical Center in Tehran, Iran, between March 1995 and October 2001 (up to 85 months follow up). Patients' sera had been routinely assayed for anti-HCV antibodies and hepatitis B surface antigen (HBsAg) at the time of transplantation. The HBsAg-positive patients were excluded from the survival analysis. Survivals were examined using Kaplan-Meier analysis and compared using the log-rank test. Multivariate analysis was performed using Cox's model. RESULTS: Forty-five patients (4.5%) were anti-HCV-antibody positive. Anti-HCV-antibody-positive patients spent a longer time on dialysis and had a higher rate of retransplantation. There were no differences in recipients' sex and age and donors' age between the two groups. The 7-year patient survival rate was 89.9% in the anti-HCV-antibody-positive group and 95.5% in the HCV-negative group (P = 0.74). Seven-year graft survival was 82.0% and 75.0% in the anti-HCV-antibody-positive and HCV-negative groups, respectively (P = 0.39). In the multivariate analysis, age was the only significant parameter correlated with patient survival (P = 0.02). CONCLUSIONS: HCV infection does not seem to influence patient and graft survival within a medium-time follow up in living allograft recipients, and anti-HCV-antibody positive status (alone) is not a contraindication for renal transplantation. However, further studies are needed to better define the role of HCV infection in long-term prognosis.  相似文献   
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