RESUMO
The nephron, functional unit of the vertebrate kidney, is specialized in metabolic wastes excretion and body fluids osmoregulation. Given the high evolutionary conservation of gene expression and segmentation patterning between mammalian and amphibian nephrons, the Xenopus laevis pronephric kidney offers a simplified model for studying nephrogenesis. The Lhx1 transcription factor plays several roles during embryogenesis, regulating target genes expression by forming multiprotein complexes with LIM binding protein 1 (Ldb1). However, few Lhx1-Ldb1 cofactors have been identified for kidney organogenesis. By tandem- affinity purification from kidney-induced Xenopus animal caps, we identified single-stranded DNA binding protein 2 (Ssbp2) interacts with the Ldb1-Lhx1 complex. Ssbp2 is expressed in the Xenopus pronephros, and knockdown prevents normal morphogenesis and differentiation of the glomus and the convoluted renal tubules. We demonstrate a role for a member of the Ssbp family in kidney organogenesis and provide evidence of a fundamental function for the Ldb1-Lhx1-Ssbp transcriptional complexes in embryonic development.
Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Pronefro , Animais , Xenopus laevis/metabolismo , Proteínas com Homeodomínio LIM/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Rim/metabolismo , Desenvolvimento Embrionário/genética , Morfogênese/genética , Pronefro/metabolismo , Proteínas de Xenopus/genética , Proteínas de Xenopus/metabolismo , Mamíferos/metabolismoRESUMO
Introduction: Diabetic foot ulcers are one of the most frequent complications of diabetes; such ulcers cause an increase in the costs of the health care of the diabetic patient and can even cause disability due to amputation in the patient. Although a proportion of patients achieve a spontaneous closure of ulcers, others require medical or surgical treatment. Objective: To determine the cost-effectiveness of the intra- and perilesional application of recombinant human epidermal growth factor (rhEGF), as opposed to conventional therapy for the management of patients diagnosed with Wagner's 3 or 4 diabetic foot ulcer in Colombia. Methodology: Using a Markov model, the process of care of a diabetic patient with diagnosis of Wagner's 3 or 4 ulcer receiving conventional treatment, or intra- and perilesional rhEGF, is configured. The evaluation cycles of the treatments are weekly over a 5-year horizon and the outcomes evaluated are quality-adjusted life years (QALYs) and the number of amputations avoided by each treatment scheme, in addition to the total costs for treatments. Results: For the analysed base case, in the outcome of amputations, it was found that the factor presents 39 fewer amputations, in a cohort of 100 patients, compared with conventional treatment. Likewise, QALYs are 0.65 more with the use of rhEGF in an average patient. The estimated cost-utility ratio for the base case would be below the threshold established for Colombia. Conclusions: The intra- and perilesional application of rhEGF is a more effective therapeutic option than conventional therapy in the treatment of patients with Wagner's 3 or 4 diabetic foot ulcers and is cost-effective, taking as an outcome the QALYs for Colombia from the perspective of the health system.