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Unpredictable hypertrophic scarring (HS) occurs after approximately 35% of all surgical procedures and causes significant physical and psychological complaints. Parallel to the need to understanding the mechanisms underlying HS formation, a prognostic tool is needed. The objective was to determine whether (systemic) immunological differences exist between patients who develop HS and those who develop normotrophic scars (NS) and to assess whether those differences can be used to identify patients prone to developing HS. A prospective cohort study with NS and HS groups in which (a) cytokine release by peripheral blood mononuclear cells (PBMC) and (b) the irritation threshold (IT) after an irritant (sodium lauryl sulphate) patch test was evaluated. Univariate regression analysis of PBMC cytokine secretion showed that low MCP‐1, IL‐8, IL‐18 and IL‐23 levels have a strong correlation with HS (P < .010‐0.004; AUC = 0.790‐0.883). Notably, combinations of two or three cytokines (TNF‐a, MCP‐1 and IL‐23; AUC: 0.942, Nagelkerke R2: 0.727) showed an improved AUC indicating a better correlation with HS than single cytokine analysis. These combination models produce good prognostic results over a broad probability range (sensitivity: 93.8%, specificity 86.7%, accuracy 90,25% between probability 0.3 and 0.7). Furthermore, the HS group had a lower IT than the NS group and an accuracy of 68%. In conclusion, very fundamental immunological differences exist between individuals who develop HS and those who do not, whereas the cytokine assay forms the basis of a predictive prognostic test for HS formation, the less invasive, easily performed irritant skin patch test is more accessible for daily practice.  相似文献   
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《Journal of endodontics》2019,45(10):1228-1236
IntroductionThe balance between the host proinflammatory immune response and the counteracting anti-inflammatory and reparative responses supposedly determine the outcome of periapical lesions. In this scenario, the vasoactive intestinal peptide (VIP) may exert a protective role because of its prominent immunoregulatory capacity. In this study, we investigated (in a cause-and-effect manner) the potential involvement of VIP in the development of human and experimental periapical lesions.MethodsPeriapical granulomas (n = 124) and control samples (n = 48) were comparatively assessed for VIP and multiple immunologic/activity marker expression through real-time polymerase chain reaction. Experimental periapical lesions (C57Bl/6 wild-type mice) were evaluated regarding endogenous VIP expression correlation with lesion development and the effect of recombinant VIP therapy in lesion outcome. CCR4KO and IL4KO strains and anti-glucocorticoid-induced TNFR-related protein inhibition were used to test the involvement of Treg and Th2 cells in VIP-mediated effects.ResultsVIP expression was more prevalent in periapical granulomas than in controls, presenting a positive association with immunoregulatory factors and an inverse association/correlation with proinflammatory mediators and the receptor activator of nuclear factor kappa B ligand/osteoprotegerin ratio. Endogenous VIP expression up-regulation was temporally associated with lesion immunoregulation and a decline of bone loss. VIP therapy in mice prompted the arrest of lesion development, being associated with an anti-inflammatory and proreparative response that limits the proinflammatory, Th1, Th17, and osteoclastogenic response in the periapex. The VIP protective effect was dependent of Treg migration and activity and independent of interleukin 4.ConclusionsOur results show that VIP overexpression in human and experimental periapical lesions is associated with lesion inactivity and that VIP therapy results in the attenuation of experimental lesion progression associated with the immunosuppressive response involving Treg cells.  相似文献   
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海水浸泡爆炸伤延期植皮最佳时机的研究   总被引:1,自引:0,他引:1  
目的确定海水浸泡爆炸伤延期植皮的最佳时机。方法建立海水浸泡爆炸伤动物模型后,分别于0、3、7、14d切取创面组织作病理切片,镜下观察创面受床的病理改变;同期对创区实施植皮术,通过计算机全自动图像分析系统准确计算出各组的皮片成活率。结果分别于伤后0、3、7、14d,对皮肤缺损区施行植皮术,发现不同时机植皮成活率不同,伤后7d对海水浸泡爆炸伤皮肤缺损区植皮,皮片成活率最高。结论海水浸泡爆炸伤延期7d后植皮是对创面实施植皮术的最佳时机。  相似文献   
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皮瓣展平法在耳廓再造时扩张皮瓣感染中的应用   总被引:1,自引:0,他引:1  
目的探索耳廓再造时扩张皮瓣感染的处理方法。方法分析中国协和医科大学整形外科医院外耳冉造中心2003年1月~2005年12月耳廓再造时耳后扩张皮瓣发生感染,经皮瓣展平法处理,感染控制后进行耳再造的12例(12耳)患者的治疗情况。结果12例(12耳)患者手术顺利,术后恢复好,再造耳效果与无感染者无明显差异。结论皮瓣展平法是耳廓再造时扩张皮瓣感染较理想的处理方法。  相似文献   
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针刺伤在采血工作中经常发生,其危害大,后果严重,一般情况下还没有引起人们足够的重视。我国是肝炎的高流行区,近年来艾滋病在我国的发病率呈倍增的趋势。血液污染的针刺伤是导致血站采血人员发生血源性传染病最主要的职业因素。作者从实际工作出发,收集相关资料,系统的阐述了针刺伤的发生因素及预防措施等,并结合相关理论提出了一系列的措施和建议。  相似文献   
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In Germany about 0.7 % of the adult population have a chronic leg ulcer. Although chronic venous insufficiency accounts for at least 80 % of all chronic leg ulcers, knowledge of the relevant differential diagnostic considerations is of crucial importance, in particular for patients who are refractory to therapy. In addition to vascular disease, other causes include neuropathic, metabolic, hematologic and exogenous factors as well as neoplasias, infections, drugs, genetic defects and some primary skin disorders. For the long‐term successful treatment of patients with chronic leg ulcers, it is necessary to identify all relevant factors, in order to enable a pathogenesis‐oriented, interdisciplinary therapeutic approach.  相似文献   
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BACKGROUND: The therapies for refractory ulcers on the oral mucosa are symptomatic and very unsatisfactory. We hypothesized that application of growth factors might be able to achieve successful remission of the lesion. We evaluated the effects of systemic administration and topical application of epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) on impaired wound healing of ulcers in the rabbit gingiva. METHODS: Almost uniform round ulcers could be created on the gingiva of the rabbits by chemical injury with acetic acid. When the submandibular glands were removed or i.v. injection of cisplatin (CDDP) and peplomycin sulfate was performed before ulcer formation, healing of the ulcers took longer than in untreated rabbits. To ascertain whether or not human EGF and bFGF affect rabbit cells, we first examined the effects of EGF and bFGF on the proliferation of the cells derived from rabbit gingiva. We then applied EGF or bFGF in these impaired healing models. RESULTS: EGF and bFGF promoted proliferation of the fibroblasts, and EGF also promoted proliferation of the keratinocytes isolated from gingival tissue of rabbits in vitro. Systemic injections of EGF and bFGF in rabbits, which had their submandibular glands removed, and topical application of bFGF accelerated healing of ulcers created in rabbits injected with CDDP and peplomycin sulfate. The ability of bFGF to promote the healing of ulcers was much greater than that of EGF. CONCLUSION: Basic FGF may be effective for refractory oral mucosal lesions.  相似文献   
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