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Howard OM  Dong HF  Su SB  Caspi RR  Chen X  Plotz P  Oppenheim JJ 《Blood》2005,105(11):4207-4214
We tested the hypothesis that interaction between autoantigens and chemoattractant receptors may be an important step in the development of autoimmunity. The retinal autoantigens S-antigen (S-Ag) and interphotoreceptor retinoid binding protein (IRBP) can induce autoimmune uveitis in rodent models. We evaluated the chemotactic activity of S-Ag and IRBP and found that both induced migration of human and mouse immature dendritic cells (iDCs) and lymphocytes, but not neutrophils, monocytes, or mature DCs. Cross-desensitization studies and single-receptor transfected cells revealed that subfamily of alpha chemokine receptors CXCR5 and CXCR3 mediated the chemotactic effect of IRBP, while only CXCR3 was required for the chemotactic response to S-Ag. Examination of the relationships between chemoattraction and the ability to elicit pathology at the protein or peptide levels in the mouse uveitis model revealed dissociation of the capacity to induce uveitis, lymphocyte proliferation, and chemoattraction. These studies suggest that IRBP and S-Ag can initiate innate and, in sensitive individuals, adaptive immune response by attracting iDCs and T and B cells expressing CXCR3 and CXCR5.  相似文献   
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The deep inferior epigastric artery perforator (DIEP) flap has been a valuable tool in breast reconstruction, but seldom in extremity reconstruction. The aim of this report is to present our experience on the use of the DIEP flap for reconstruction of soft‐tissue defects in the extremities of pediatric patients. From January 2007 to February 2011, 22 consecutive free DIEP flap transfers were performed for reconstruction of complex soft‐tissue defects in the extremities of children with a mean age of 5.7 years old (ranging 2–10 years old). The flap design included transverse, oblique, and irregular DIEP flaps, containing one to three perforators in the flap. The flap size ranged from 7 × 4 cm to 18 × 17 cm. Primary donor‐site closure was accomplished in all of patients. The postoperative course was uneventfully in most of cases. The venous congestion was observed in two cases. One case of venous congestion was caused by flap inset with tension. The other case with venous thrombosis ended with partial loss of the flap after salvage procedure. There was one total flap loss due to the arterial thrombosis. The flap survival rate was 95.5%. The mean follow‐up was 12 months (ranging 6–36 months). All reconstructed extremities had satisfactory aesthetic and functional outcomes except two cases undergoing the secondary debulking procedures. The donor sites healed well in all cases without complications. Our experience showed that the free DIEP flap could be an alternative for reconstruction of soft‐tissue defects in the extremities of children. © 2013 Wiley Periodicals, Inc. Microsurgery 33:612–619, 2013.  相似文献   
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The molecular characterization of the mutations in hemophilia A patients is hampered by the large size of the factor VIII gene and the great heterogeneity of mutations. In this study, we have performed a protocol involving multiplex polymerase chain reaction in which 19 exons were amplified in four different combinations followed by nonradioactive single-strand conformational polymorphism (SSCP) to screen for mutations. Southern blotting was used to detect inversion of the factor VIII gene resulting from recombination between copies of the gene A (F8A) located in intron 22 of the factor VIII gene and two copies close telomeric region of X chromosome. Forty-two hemophilia A patients (21 with severe and 21 with mild-to-moderate disease) were studied. The inversion of factor VIII occurred in 13 of 21 patients affected by severe hemophilia A. One patient showed a large extra band in addition to the three bands observed after Southern blotting with the F8A probe. An abnormal electrophoretic pattern of SSCP was detected in 85% and 50% of the patients affected by mild-to-moderate and severe disease, respectively. Sixteen different mutations were identified. Eleven mutations were novel and comprised 9 point mutations and 2 small deletions. This study shows that the methodology used is safe and rapid and has potential for detecting almost all of the genetic defects of the studied hemophilia A patients.  相似文献   
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Online forums for chronic health conditions emerged as early as 30 yr ago and interest in their study has blossomed. Type 1 diabetes (T1D) forums have grown exponentially since 2005. Therefore, a comprehensive evaluation of these forums is needed. This study assesses the demographics and motivations of parents who use type 1 diabetes forums and the potential impact that forum membership (FM) has on parenting stress and hypoglycemic fear. One hundred and two parents were recruited through online T1D forums and asked to complete qualitative and quantitative measures of their experience with the T1D forums. Results of this study suggest that parents who use T1D forums mirror those who participate in clinic‐based research protocols and are primarily motivated to participate in forums to increase their diabetes knowledge and gain social support. Indeed, parents who use T1D forums report high levels of trust, social support, and perceived knowledge gained. However, FM was positively related to increased self‐reported parenting stress frequency and hypoglycemic fear behaviors. Taken together, the relationships formed within these communities may have a significant impact on the experience of these caregivers. The need for future research and potential implications for physicians, including parent debriefing, are discussed.  相似文献   
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Objective. Treatment with high-dose (400 mg/kg/day) intravenous immunoglobulin (IVIg) shows benefit in many autoimmune diseases but is very expensive. Low-dose IVIg has also been shown to be effective in inhibiting adjuvant arthritis in the rat. This pilot, randomized, double-blind, placebo-controlled trial was conducted to assess the use of low-dose IVIg in patients with treatment-refractory rheumatoid arthritis (RA). Methods. Twenty patients with active RA were recruited. Ten patients received IVIg and 10 received albumin. Study subjects were given 6 courses of either IVIg (5 mg/kg) or albumin (5 mg/kg), once every 3 weeks. Baseline medications were continued and not changed throughout the study. Results. There were no complications. Five patients dropped out before the 18-week followup visit. No significant differences between treatment groups were noted during the 18-week trial in terms of global activity indices (patient or physician assessment), joint swelling, joint pain or tenderness, erythrocyte sedimentation rate, C-reactive protein level, or rheumatoid factor. The protocol was terminated prematurely because of reported contamination of IVIg by hepatitis C virus. None of the patients showed evidence of hepatitis C infection by serologic analysis or by polymerase chain reaction. Conclusion. Low-dose IVIg, as administered in this trial, does not show a therapeutic effect in patients with refractory RA.  相似文献   
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Care for patients who experience out-of-hospital cardiac arrest (OHCA) has rapidly evolved in the past decade. Increased sophistication of care in the community, emergency medical services (EMS) and hospital setting is associated with improved patient-centred outcomes. Notably, Utstein survival doubled from 11.6% to 23.1% between 2011 and 2016. These achievements involved collaboration between policymakers, clinicians and researchers, and were made possible by a strategic interplay of policy, research and implementation. We review the development and current state of OHCA in Singapore using primary population-based data from the Pan-Asian Resuscitation Outcomes Study and an unstructured search of research databases. We discuss the roles of important milestones in policy, community, dispatch, EMS and hospital interventions. Finally, we relate these interventions to relevant processes and outcomes, such as the relationship between the strategic implementation of bystander cardiopulmonary resuscitation and placement of automated external defibrillator with return of spontaneous circulation, survival to discharge and survival with favourable neurological outcomes.  相似文献   
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