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31.
Park C‐S, Kim K‐H, Im S‐A, Song S, Lee C‐K. Identification of HLA‐DR4‐restricted immunogenic peptide derived from xenogenic porcine major histocompatibility complex class I molecule. Xenotransplantation 2012; 19: 317–322. © 2012 John Wiley & Sons A/S. Abstract: Indirect recognition of xenoantigens has been implicated as the major mechanism underlying xenospecific CD4+ T‐cell activation in chronic rejection. We identified swine leukocyte antigen (SLA)‐derived immunogenic peptides that are presented in the context of human HLA‐DR4 molecules. The SLA class I‐derived peptides that bind HLA‐DRB1*0401, a representative of the DR4 supertype, were predicted using a computer‐assisted algorithm. The candidate peptides were synthesized, and their binding capacities to HLA‐DRB1*0401 were compared in a competitive ELISA using biotinylated hemagglutinin reporter peptides [HA307‐319]. Peptide‐11 (LRSWTAADTAAQISK) was determined to exhibit the most potent binding capacity to HLA‐DRB1*0401 in vitro and thus selected for in vivo immunization. Immunization of HLA‐DRB1*0401‐transgenic mice with peptide‐11 elicited potent CD4+ Th1 responses. Peptide‐11 shares homology to α2 domains of three SLA‐1 alleles, six SLA‐2 alleles, and 14 SLA‐3 alleles. Thus, this study has important implications not only for the identification of an immunogenic indirect epitope shared by diverse SLA class I alleles, but also for the development of epitope‐specific immunoregulation strategies.  相似文献   
32.

Background

Treatments for chronic perilunate or lunate dislocations are very difficult and associated with poor prognoses. There is no established treatment method and are still many controversies.

Case Presentation

We reported three cases of chronic neglected lunate volar dislocation treated with a novel surgical technique. All three cases were males with wrist pain and tingling sensation. Radiographs confirmed chronic volar dislocation of the lunate. Open reduction was performed by combined volar and dorsal approaches. After anatomical reduction, scapholunate and lunotriquetral interosseous ligament reconstructions were performed with the palmaris longus tendon and synthetic tape. The patients had an uneventful postoperative period with satisfactory functional outcomes at the last follow-up.

Conclusions

We believe that open reduction and interosseous ligament reconstruction using the autogenous tendon and synthetic tape may be a valuable option for treating chronic volar dislocation of the lunate.  相似文献   
33.
The aims of this study were to establish reference data for bone mineral density (BMD) at central skeletal sites using Lunar dual-energy X-ray absorptiometry (DXA), and to estimate the age-and sex-specific prevalence of osteoporosis in a Korean population. We performed a population-based, cross-sectional study. The subjects were 4148 (1810 men and 2338 women) Korean adults, aged 20–79 years. The BMD for central sites (lumbar spine, femoral neck, trochanter, and Ward’s triangle) were measured by DXA. The standardized prevalence of osteoporosis among individual aged 50–79 years in lumbar spine, femoral neck, Ward’s triangle, and trochanter was 40.1%, 12.4%, 28.4%, and 4.4% in women and 6.5%, 5.9%, 3.7%, and 1.6% in men, respectively. In women, peak BMD occurred in the age range 40–49 years for the femoral neck and trochanter, 30–39 years for the lumbar spine, and 20–29 years for Ward’s triangle. In men, peak BMD values were observed at 20–29 years for all measured sites. This study establishes a normative database for BMD at central skeletal sites using dualenergy X-ray absorptiometry and provides more reliable information on the prevalence of osteoporosis in Korea.  相似文献   
34.
Kim DH  Lee NY  Sohn SK  Baek JH  Kim JG  Suh JS  Lee KB  Shin IH 《Transplantation》2005,79(11):1615-1622
BACKGROUND: The current study attempted to evaluate the association between IL-10 promoter gene polymorphism and transplant outcomes including the occurrence of chronic graft-versus-host disease (GVHD) and its clinical course during systemic immunosuppressive treatment (IST) among 60 recipients of cytokine-mobilized peripheral blood stem cell (PBSC) from HLA-matched sibling donors. METHODS: We analyzed 3 single-nucleotide polymorphisms in proximal region of IL-10 promoter gene (-1082/-819/-592). RESULTS: In the current study, only two haplotypes (1082*A/819*T/592*A [ATA] and 1082*A/819*C/592*C [ACC]) were found. An increased occurrence of chronic GVHD was noted dependent on the IL-10 haplotypes (43% vs. 68% vs. 96% in ACC/ACC vs. ATA/ACC vs. ATA/ATA haplotype, P=0.003). In a logistic regression based on multinomial model, ATA/ATA homozygote had 7-fold increasing risk of the development of chronic GVHD compared with ACC/ACC homozygote. The incidence of chronic GVHD at 1 year was 46%+/-20%, 64%+/-10%, and 82%+/-5% in ACC/ACC, ATA/ACC and ATA/ATA group, respectively (P=0.0266). Plus, the duration of systemic IST was significantly shorter in recipients without ATA-haplotype comparing with those with ATA haplotype (339 days vs. 1,146 days, P=0.0091). CONCLUSION: IL-10 promoter gene polymorphism was found to be apparently associated with chronic GVHD after allogeneic peripheral blood stem cell transplantation from HLA-matched sibling donors.  相似文献   
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36.
OBJECTIVE: Adipose tissue-derived mesenchymal stem cells (ATMSCs) have been shown to differentiate into bone, cartilage, fat or muscle. However, it is not certain that ATMSCs are equal to bone marrow-derived mesenchymal stem cells (BMMSC) for their bone and cartilage forming potential. The purpose of this study was to answer the question. METHODS: BMMSCs were obtained from the medullary canal of femur and ATMSCs were isolated from the fat harvested during liposuction procedures. After cell expansion in culture media and two passages, the immunofluorescent studies for STRO-1 and CD34 were performed to characterize the BMMSCs and ATMSCs. Osteogenesis was induced on a monolayer culture with osteogenic medium containing dexamethasone, beta-glycerophosphate and ascorbate. After 2-3 weeks, alkaline phosphatase (AP) and Von Kossa staining were done. To test for chondrogenesis, mesenchymal stem cells (MSCs) were cultured in a pellet culture and in a fibrin scaffold with a chondrogenic medium (CM) containing transforming growth factor-beta(2) and insulin-like growth factor-I. After 4 weeks, Safranin-O staining and immunohistochemical staining for type II collagen were done to evaluate the chondrogenic differentiation and the matrix production. A histological scale was used to semiquantitatively assess the degree of chondrogenesis. RESULTS: Both BMMSCs and ATMSCs were STRO-1 positive and CD34 negative. On the test of osteogenesis, the osteoblastic differentiation of ATMSCs as demonstrated by AP staining was much less than that of the BMMSCs (P=0.002). The amount of matrix mineralization shown by Von Kossa staining also showed statistical differences between the two MSCs (P=0.011). On the test for chondrogenesis by the pellet culture ATMSCs showed much weaker presentation as chondrogenic cells in both cell morphology and the matrix production. The histological score was 6.5 (SD1.3) for the BMMSCs, and 4.3 (SD1.6) for the ATMSCs cultured in CM, which was statistically significant (P=0.023). The results from fibrin gel paralleled those from the pellet culture in general. CONCLUSION: The results of our study suggest that the ATMSCs may have an inferior potential for both osteogenesis and chondrogenesis compared with the BMMSCs, and these cast doubts on the value of adipose tissue as a source of MSCs.  相似文献   
37.
目的探讨重型颅脑损伤开颅术中急性脑膨出原因及防治。方法对术中出现急性脑膨出的46例病人进行回顾性分析。结果导致脑膨出的主要原因有迟发性颅内血肿、急性弥漫性脑肿胀、低血压、低血氧及较大回流静脉的损伤。结论术中出现急性脑膨出的病因是多方面的,针对不同的病因采取相应的措施,可以减轻脑组织的损害,降低病死率。  相似文献   
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39.
We report the sonographic appearance of a rare case of neuritis ossificans of the median nerve at the wrist, which appeared as a hyperechoic lesion around the nerve. Diagnosis was confirmed with magnetic resonance imaging (MRI).  相似文献   
40.
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