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51.
Non-invasive bioluminescence imaging (BLI) to monitor changes in gene expression of cells implanted in live animals should facilitate the development of biomaterial scaffolds for tissue regeneration. We show that, in vitro, induction of chondrogenic differentiation in mouse bone marrow stromal cell line (CL1) and human adipose tissue derived mesenchymal stromal cells (hAMSCs), permanently transduced with a procollagen II (COL2A1) promoter driving a firefly luciferase gene reporter (PLuc) (COL2A1p·PLuc), induces PLuc expression in correlation with increases in COL2A1 and Sox9 mRNA expression and acquisition of chondrocytic phenotype. To be able to simultaneously monitor in vivo cell differentiation and proliferation, COL2A1p·PLuc labelled cells were also genetically labelled with a renilla luciferase (RLuc) gene driven by a constitutively active cytomegalovirus promoter, and then seeded in demineralized bone matrix (DBM) subcutaneously implanted in SCID mice. Non-invasive BLI monitoring of the implanted mice showed that the PLuc/RLuc ratio reports on gene expression changes indicative of cell differentiation. Large (CL1) and moderated (hAMSCs) changes in the PLuc/RLuc ratio over a 6 week period, revealed different patterns of in vivo chondrogenic differentiation for the CL1 cell line and primary MSCs, in agreement with in vitro published data and our results from histological analysis of DBM sections. This double bioluminescence labelling strategy together with BLI imaging to analyze behaviour of cells implanted in live animals should facilitate the development of progenitor cell/scaffold combinations for tissue repair.  相似文献   
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Background/Aims: A pretherapy serum alanine aminotransferase (ALT) level above five times the upper limit of normal (ULN) is known to predict hepatitis B e antigen (HBeAg) seroconversion during lamivudine therapy for chronic hepatitis B patients. However, whether an even higher pretherapy serum ALT value or other viral factors could affect treatment responses remains unclear. Patients and methods: A total of 253 HBeAg‐positive chronic hepatitis B patients who had a pretherapy serum ALT level over five times ULN and received lamivudine for 12–18 months were retrospectively collected. Among these patients, 38% had received prior lamivudine treatment. HBeAg seroconversion was the primary endpoint of treatment. Baseline clinical and viral features were compared between responders and non‐responders at the end of treatment and 6 months post‐treatment. Results: At the end of therapy, the overall HBeAg seroconversion rate was 33.6%. For lamivudine‐naïve patients, the HBeAg seroconversion rate was 37.8%. Subgroup analysis showed that patients with pretherapy ALT levels over 10 times ULN had a significantly higher HBeAg seroconversion rate than those with a pretherapy ALT level between five and 10 times ULN at 3 months (P=0.045) and 6 months (P=0.037) of lamivudine treatment. No significant difference was found in terms of pretherapy serum ALT values, viral load and genotypes between seroconverters and non‐seroconverters. Conclusions: For lamivudine‐treated HBeAg‐positive patients with pretherapy ALT levels over five times ULN, an even higher ALT level could predict earlier HBeAg seroconversion; however, neither ALT levels nor viral factors correlate with higher response rates after 12–18 months of treatment.  相似文献   
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Clinical Oral Investigations - A proportion of oral squamous cell carcinoma (OSCC) is preceded by oral potentially malignant disorders (OPMD), and the rest might not be associated with any...  相似文献   
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BACKGROUND: The proliferative activity of some tumors is related to the development of metastatic disease and survival. Thus it could be used as a potential prognostic variable. OBJECTIVE: The purpose of this study was to determine the prognostic value of the Ki-67 index and of a "proliferation-based prognostic index" (PBPI, derived as tumor thickness x Ki-67 index/100) in localized cutaneous malignant melanoma (CMM). METHODS: The Ki-67 index (percent of total tumor nuclei) was determined in a series of 84 localized CMMs, with the use of the alkaline phosphatase-antialkaline phosphatase labeling method in formalin-fixed, paraffin-embedded material, and was correlated with other prognostic variables. Survival analysis was performed to determine whether the Ki-67 index and the PBPI could be predictive of metastatic spread or recurrent disease. A stratified analysis of these two parameters according to the tumor thickness was done. RESULTS: An association among the Ki-67 index and location, Clark level, tumor thickness and stage, and prognostic index was detected. Increased Ki-67 index and PBPI were associated with poorer overall survival (P =.03 and P <.0001, respectively) and disease-free survival (P =.01 and P <.0001, respectively). However, after stratification for thickness, only the PBPI showed independent prognostic significance, restricted to tumors thicker than 4 mm (P =. 03). CONCLUSION: The determination of the PBPI in CMM conveys prognostic information for localized thick (>4 mm) CMM, identifying two groups of patients with distinct outcome.  相似文献   
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Following skin wounding, the healing outcome can be: regeneration, repair with normal scar tissue, repair with hypertrophic scar tissue or the formation of keloids. The role of chemical factors in wound healing has been extensively explored, and while there is evidence suggesting the role of mechanical forces, its influence is much less well defined. Here, we provide a brief review on the recent progress of the role of mechanical force in skin wound healing by comparing laboratory mice, African spiny mice, fetal wound healing and adult scar keloid formation. A comparison across different species may provide insight into key regulators. Interestingly, some findings suggest tension can induce an immune response, and this provides a new link between mechanical and chemical forces. Clinically, manipulating skin tension has been demonstrated to be effective for scar prevention and treatment, but not for tissue regeneration. Utilising this knowledge, specialists may modulate regulatory factors and develop therapeutic strategies to reduce scar formation and promote regeneration.  相似文献   
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Renal transplantation is the treatment of choice for children with ESRD offering advantages of improved survival, growth potential, cognitive development, and quality of life. The aim of our study was to compare the outcomes of LDKT vs DDKT performed in children at a single center. Retrospective chart review of pediatric patients who underwent kidney transplantation from 2005 to 2014 was performed. Ninety‐one renal transplants were accomplished, and 31 cases (38.27%) were LDKT, and in 96.7% of the cases, the graft was obtained through laparoscopy. Thirty‐four receptors weighted <25 kg. LDKT group had statistically significant lower cold ischemia times than DDKT one. Complication rate was 9.67% for LDKT and 18.33% for DDKT. eGFR was better in LDKT. Patient survival rate was 100% for LDKT and 98.3% for DDKT, and graft survival rate was 96.7% for LDKT and 88.33%‐80% for DDKT at a year and 5 years. Our program of pediatric kidney transplantation has achieved optimal patient and graft survival rates with low rate of complications. Living donor pediatric kidney transplants have higher patient and better graft survival rates than deceased donor kidney transplants.  相似文献   
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