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Vlad C. Sandulache PhD ; Aron Parekh PhD ; HaSheng Li-Korotky MD PhD ; Joseph E. Dohar MD MS ; Patricia A. Hebda PhD 《Wound repair and regeneration》2007,15(1):122-133
Keloid formation has been linked to aberrant fibroblast activity, exacerbated by growth factors and inflammatory mediators. Prostaglandin E2 (PGE2), synthesized from arachidonic acid by cyclooxygenases (COX) and synthases (PGES), acts as both an inflammatory mediator and fibroblast modulator. Although PGE2 has known antifibrotic effects in the lower airway, its role in dermal fibrosis in general, and keloid formation in particular, remains unclear. This study focused on: (1) the effects of PGE2 on keloid fibroblast migration, contraction, and collagen synthesis and (2) endogenous PGE2 synthesis in response interleukin-1beta. PGE2 decreased keloid fibroblast migration and contraction via an EP2/EP4-cAMP mechanism that disrupted actin cytoskeletal dynamics and reversed transforming growth factor-beta1-induced collagen I and III synthesis. Impaired fibroblast PGE2 production has been linked to lower airway fibrosis and recently to keloid formation. Here, we showed that interleukin-1beta stimulation leads to nuclear factor-kappaB translocation to the nucleus, resulting in up-regulation of COX-2 and microsomal PGE2 synthase 1. Up-regulation of COX-2 in, and secretion of PGE2 by keloid fibroblasts are diminished compared with their normal fibroblast counterparts. We suggest that the antifibrotic effects of PGE2 during keloid formation are potentially diminished due to aberrant paracrine fibroblast signaling. Exogenous PGE2 may supplement decreased endogenous levels and inhibit keloid formation or progression. 相似文献
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Nuri Karabay MD Tulgar Toros MD Can Hurel MD 《The Journal of foot and ankle surgery》2007,46(6):442-446
The heels of 23 patients who were diagnosed with unilateral/bilateral plantar fasciitis were evaluated via ultrasonography and compared with their asymptomatic feet and a control group of 23 people. Plantar fascial thickness, echogenity, and heel pad thickness were evaluated, and the results were statistically analyzed. For symptomatic feet, increased thickness of the fascia and reduced echogenity were constant ultrasonographic findings (mean, 4.79 mm for symptomatic feet; 2.17 mm for control group, P < .05). No significant difference was found between heel pads of the diseased and healthy feet (mean, 12.96 mm for symptomatic feet; 13.10 mm for control group; P > .05). Ultrasonography seems to be a valuable, noninvasive diagnostic tool for the evaluation of plantar fasciitis. 相似文献
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BACKGROUND: In the area of endovenous chemical ablation (sclerotherapy), there has been much debate regarding sclerosant quality and efficacy. Only sodium tetradecyl sulfate (STS) has garnered Food and Drug Administration (FDA) approval in the United States. OBJECTIVE: The primary objective of this study was to compare clinical performance measures of compounded STS from 27% industrial-strength stock (compounded STS) versus FDA-approved Sotradecol (Bioniche Pharma USA, Inc., Belleville, Ontario, Canada). MATERIALS AND METHODS: Phase I of this study focused on the chemical composition of the drugs, whereas Phase II studied the ablative abilities of the two drugs at comparable concentrations of 3%. RESULTS: We documented the presence of various impurities in compounded STS. No impurities in AngioDynamics STS were found. Our studies suggest that compounded STS may have significant variation in concentration. The AngioDynamics STS concentration was found to be manufactured within a tight tolerance. Segments of incomplete ablation were more frequent in the compounded STS group when compared to the AngioDynamics STS group. This reached statistical significance (p=.02). Primary closure using the Kaplan-Meier statistic demonstrated a trend in the favor of AngioDynamics STS when compared to compounded STS. CONCLUSION: When product quality, efficacy, and liability are carefully considered, we conclude that it would behoove physicians to use pharmaceutical-grade, FDA-approved sclerosant when treating their patients. 相似文献
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Arteriovenous malformation of the foot is very uncommon, and surgical closure after its treatment with embolization and total excision may be challenging for the foot surgeon, particularly in distally localized lesions. A popular method to cover these difficult wounds is free-tissue transfer, which is a highly demanding procedure. Alternatively, distally based regional flaps have been occasionally reported for clinical use in such distant foot defects. Herein, we present a 36-year-old female patient with a diagnosis of arteriovenous malformation arising in the distal medial plantar and dorsal surfaces of the right foot. After surgical resection of the vascular lesion preceded by a misapplied embolization procedure, an extended lateral supramalleolar flap was successfully transferred to the defect area, covering it completely. Functional and aesthetic outcome was satisfactory after 6 months follow-up. Extended lateral supramalleolar flap is a useful and reliable choice for distal foot reconstructions. 相似文献
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