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31.
To realize the therapeutic potential of mesenchymal stem cells (MSCs), we aimed to develop a method for isolating and expanding New Zealand rabbit MSCs in a great scale. Rabbit MSCs expanded under hypoxic and normoxic conditions were compared in terms of replication capacity, differentiation potential, and the capacity for allogeneic transplantation in a calvarial defect model. The cells from all tested rabbits were expanded more rapidly when plated at low‐density under hypoxic conditions compared to under normoxic conditions. Moreover, cells expanded under hypoxic conditions increased in the potential of osteoblastic, adipocytic, and chondrocytic differentiation. More importantly, radiographic analysis and micro‐CT measurement of bone volume revealed the hypoxic cells when transplanted in the calvarial defects of another rabbit increased in the ability to repair bone defect compared to the normoxic cells. Six weeks after allogeneic transplantation of hypoxic MSCs, histological analysis revealed a callus spanned the length of the defect, and several bone tissues spotted in the implant. At 12 weeks, new bone had formed throughout the implant. Using BrdU labeling to track the transplanted cells, the hypoxic cells were more detected in the newly formed bone compared to the normoxic cells. For defects treated with allogeneic MSCs, no adverse host response could be detected at any time‐point. In conclusion, we have developed a robust method for isolation and expansion of rabbit MSCs by combining low‐density with hypoxic culture, which can be applied for the design of clinical trials in allogeneic transplantation of MSCs for bone healing. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 30:1213–1220, 2012  相似文献   
32.
Background Nonsurgical assessment of sentinel nodes (SNs) would offer advantages over surgical SN excision by reducing morbidity and costs. Proton magnetic resonance spectroscopy (MRS) of fine-needle aspirate biopsy (FNAB) specimens identifies melanoma lymph node metastases. This study was undertaken to determine the accuracy of the MRS method and thereby establish a basis for the future development of a nonsurgical technique for assessing SNs. Methods FNAB samples were obtained from 118 biopsy specimens from 77 patients during SN biopsy and regional lymphadenectomy. The specimens were histologically evaluated and correlated with MRS data. Histopathologic analysis established that 56 specimens contained metastatic melanoma and that 62 specimens were benign. A linear discriminant analysis–based classifier was developed for benign tissues and metastases. Results The presence of metastatic melanoma in lymph nodes was predicted with a sensitivity of 92.9%, a specificity of 90.3%, and an accuracy of 91.5% in a primary data set. In a second data set that used FNAB samples separate from the original tissue samples, melanoma metastases were predicted with a sensitivity of 87.5%, a specificity of 90.3%, and an accuracy of 89.1%, thus supporting the reproducibility of the method. Conclusions Proton MRS of FNAB samples may provide a robust and accurate diagnosis of metastatic disease in the regional lymph nodes of melanoma patients. These data indicate the potential for SN staging of melanoma without surgical biopsy and histopathological evaluation.  相似文献   
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To evaluate the outcome of patients with locally advanced low rectal adenocarcinoma who required preoperative concurrent chemoradiotherapy (CCRT), a total of 22 patients underwent preoperative CCRT and radical resection for locally advanced low rectal adenocarcinoma. Patients received concurrent chemotherapy with high-dose 5-fluorouracil (5-FU) in continuous infusion and leucovorin and preoperative radiation with a mean dose of 50.4 Gy (range, 45-50.4 Gy). Radical resection surgery was performed 6 weeks after treatment. Fifty-five percent of patients achieved tumor downstaging, and 14% patients. showed pathological complete remission. No severe hematological and gastrointestinal toxicity of preoperative CCRT was noted. Sphincter-saving rate was 82%, and there were no deaths related to preoperative CCRT and surgery. Overall, 3-year survival rate was 69%, and a rate of locoregional recurrence was 13.6%. This study shows that many patients with locally advanced rectal cancer can be operated on with sphincter-saving radical resection surgery under good local control after preoperative concurrent chemoradiotherapy, which induces tumor downstaging.  相似文献   
35.
Pigmented villonodular synovitis (PVNS) is a benign tissue proliferation characterized by its hyper‐vascularity within the lesion. The true etiology and cell source of this disease entity still remain unclear. Mesenchymal stem cells (MSCs) exist in various tissues of human body. However, it has not been clarified whether MSCs could be isolated from tissue of PVNS. Here, we isolated MSCs from PVNS (PVNS‐SCs), and by comparing to the MSCs from normal synovium (Syn‐SCs) of the same individual, we investigated whether PVNS‐SCs differed in the capacity for multi‐differentiation and inducing angiogenesis. We first demonstrated that PVNS‐SCs existed in the lesion of PVNS of three individuals. Moreover, we showed PVNS‐SCs had better osteogenic differentiation potential than Syn‐SCs, whereas Syn‐SCs had better capacity for adipogenic and chondrogenic differentiation. By genome–wide analysis of gene expression profile using a complementary DNA microarray and comparing to Syn‐SCs, we identified in PVNS‐SCs a distinct gene expression profile characterized by up‐regulation of genes involved in angiogenesis. In vitro and in vivo studies further confirmed that PVNS‐SCs had better capacities for promoting angiogenesis. In summary, the identification of PVNS‐SCs in PVNS tissue and their distinct angiogenic potential may help elucidate the underlying etiology of this disease. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:395–403, 2016.  相似文献   
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Active pronation is important for many activities of daily living. Loss of median nerve function including pronation is a rare sequela of humerus fracture. Tendon transfers to restore pronation are reserved for the obstetrical brachial plexus palsy patient. Transfer of expendable motor nerves is a treatment modality that can be used to restore active pronation. Nerve transfers are advantageous in that they do not require prolonged immobilization postoperatively, avoid operating within the zone of injury, reinnervate muscles in their native location prior to degeneration of the motor end plates, and result in minimal donor deficit. We report a case of lost median nerve function after a humerus fracture. Pronation was restored with transfer of the extensor carpi radialis brevis branch of the radial nerve to the pronator teres branch of the median nerve. Anterior interosseous nerve function was restored with transfer of the supinator branch to the anterior interosseous nerve. Clinically evident motor function was seen at 4 months postoperatively and continued to improve for the following 18 months. The patient has 4+/5 pronator teres, 4+/5 flexor pollicis longus, and 4−/5 index finger flexor digitorum profundus function. The transfer of the extensor carpi radialis brevis branch of the radial nerve to the pronator teres and supinator branch of the radial nerve to the anterior interosseous nerve is a novel, previously unreported method to restore extrinsic median nerve function.  相似文献   
38.
Background  Gynecomastia is enlargement of the male breast caused by gland proliferation. Surgery is performed for symptom relief or for cosmetic reasons. The authors used a modified operative procedure, then evaluated the results and safety. Methods  Between 2001 and 2005, 22 men (median age, 26 years; range, 13–63 years) with gynecomastia underwent surgery. The operative procedure included a zigzag periareolar skin incision, eccentric subcutaneous mastectomy, and liposuction, with postoperative compression. Results  All the patients were satisfied with the results of the surgery, which produced a chest contour resembling a normal male chest rather than simply a smaller breast. The only complication was a hematoma. One patient was found to have breast cancer. Conclusions  The normal male chest contour can be restored by the described method of eccentric subcutaneous mastectomy.  相似文献   
39.
Until recently, little consideration was placed on the integrity of the subscapularis tendon after total shoulder arthroplasty. We have noted that several of our patients exhibited loss of internal rotation strength and subscapularis function after total shoulder arthroplasty utilizing an anatomic soft tissue repair of the subscapularis, both with and without bone tunnels. On the basis of those results, we began removing the subscapularis with a small piece of bone by a lesser tuberosity osteotomy in an attempt to achieve improved subscapularis function through bony healing at the repair site. A retrospective review of 28 patients (30 shoulders) was done of patients who had total shoulder arthroplasty performed between 2001 and 2003. The lesser tuberosity and attached subscapularis were repaired through bone tunnels in all cases. The mean follow-up was 1.1 years. Terminal internal rotation was evaluated by the belly-press examination. Subscapularis function was assessed by the patient's ability to tuck in a shirt behind the back, and 25 of 30 patients (83.3%) reported no difficulty. Belly-press examination results were normal in 18 of 30 patients (60%). Removal of the subscapularis through a lesser tuberosity osteotomy results in reliable restoration of internal rotation strength after total shoulder arthroplasty, as measured by the ability to perform a stomach press and to tuck in a shirt. In comparing these results with our earlier cohort of patients with similar demographics and postoperative rehabilitation that had soft tissue repair, improved results were seen in the group that underwent lesser tuberosity osteotomy.  相似文献   
40.
SUMO4 M55V variant is associated with diabetic nephropathy in type 2 diabetes   总被引:15,自引:0,他引:15  
Lin HY  Wang CL  Hsiao PJ  Lu YC  Chen SY  Lin KD  Hsin SC  Hsieh MC  Shin SJ 《Diabetes》2007,56(4):1177-1180
OBJECTIVE-SUMO4 mRNA was recently found to be mainly expressed in the kidney, and the methionine-to-valine substitution at codon 55 (M55V) variant of SUMO4 may induce higher nuclear factor-kappaB (NF-kappaB) activity. Because NF-kappaB is known to mediate the development of diabetic nephropathy, we examined the association between the SUMO4 M55V variant and the severity of diabetic nephropathy. RESEARCH DESIGN AND METHODS-We recruited a total of 430 patients with type 2 diabetes. The M55V (rs237025, 163A-->G) polymorphism of SUMO4 was genotyped by real-time PCR, and urine albumin concentration was measured by radioimmunoassay. RESULTS-The frequencies of SUMO4 AA, GA, and GG were 52.6, 40.7, and 6.7%, respectively, in the normoalbuminuric group; 45.5, 47.3, and 7.1% in the microalbuminuric group; and 36.9, 46.2, and 16.9% in the macroalbuminuric group. We detected a significant linear trend for SUMO4 genotype between the macroalbuminuric and normoalbuminuric groups. The mean urine albumin-to-creatinine ratio (42.3 +/- 108.82 mg/mmol) in the GG group was significantly higher than in the AA (14.9 +/- 51.49 mg/mmol) and GA (17.0 +/- 43.74 mg/mmol) groups. Multivariate logistic regression analysis showed the SUMO4 M55V variant to be independently associated with the severity of diabetic nephropathy. CONCLUSIONS-This study indicates that the SUMO4 gene M55V variant is associated with severity of diabetic nephropathy in patients with type 2 diabetes.  相似文献   
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