Reconstrucción microquirúrgica en pandemia por Covid-19 / MICROSURGICAL RECONSTRUCTION IN THE COVID - 19 PANDEMIC

Introducción: la Pandemia por SARS CoV ­ 2 (COVID ­ 19) tuvo un impacto significativo en el desarrollo de los servicios quirúrgicos en general y obligo a establecer protocolos de actuación para las distintas patologías a fin de cuidar al máximo los recursos humanos y la capacidad instalada de los hospitales para hacer frente a esta contingencia mundial. Objetivos: presentar una casuística de 7 pacientes con reconstrucción microquirúrgica de patología de cabeza y cuello en estadios avanzados y patología de miembros inferiores durante la pandemia por COVID - 19. Materiales y Métodos: trabajo retrospectivo, se revisaron las historias clínicas físicas y digitales. Se incluyeron 5 pacientes con patología avanzada de cabeza y cuello y 2 pacientes con patología de miembros inferiores. Resultados: cinco pacientes fueron operados por patología avanzada de cabeza y cuello: 3 pacientes con carcinomas escamosos de cavidad oral estadio IVa, 1 paciente con carcinoma escamoso de piel avanzado estadio IV y 1 paciente con fractura compleja de maxilar inferior por herida de arma de fuego con fistula oro-cutánea crónica, con exposición del material de osteosíntesis, mala oclusión y pérdida de peso importante por dificultad para alimentación. Dos pacientes fueron operados por patología de miembros inferiores en tercio inferior de pierna, uno por fractura expuesta grave con defecto de tejidos blandos y el otro por una ulcera arterial. Conclusión: la cirugía reconstructiva microquirúrgica puede realizarse con buenos niveles de seguridad para el personal de salud y para los pacientes afectados por patologías avanzadas de cabeza y cuello y otras patologías que requieran colgajos libres. Es fundamental respetar estrictamente los protocolos para evitar los contagios en el medio intrahospitalario, entendiendo que debe considerarse todo paciente que ingrese al hospital como COVID (+) hasta que se demuestre lo contrario

Introduction: the SARS CoV ­ 2 (COVID ­ 19) Pandemic had a significant impact on the development of surgical services in general and forced the establishment of action protocols for the different pathologies in order to take maximum care of human resources and capacity. installed in hospitals to deal with this global contingency. Objectives: to present a casuistry of 7 patients with microsurgical reconstruction of head and neck pathology in advanced stages and lower limb pathology during the COVID - 19 pandemic. Materials and Methods: retrospective work, physical and digital medical records were reviewed. Five patients with advanced head and neck disease and 2 patients with lower limb disease were included. Results: five patients underwent surgery for advanced head and neck disease: 3 patients with stage IVa squamous cell carcinoma of the oral cavity, 1 patient with stage IV advanced squamous cell carcinoma of the skin, and 1 patient with a complex fracture of the lower jaw due to a gunshot wound. with chronic oro-cutaneous fistula, with exposure of the osteosynthesis material, poor occlusion and significant weight loss due to difficulty feeding. Two patients underwent surgery for pathology of the lower limbs in the lower third of the leg, one for a severe open fracture with a soft tissue defect and the other for an arterial ulcer. Conclusion: microsurgical reconstructive surgery can be performed with good levels of safety for health personnel and for patients affected by advanced pathologies of the head and neck and other pathologies that require free flaps. It is essential to strictly respect the protocols to avoid contagion in the hospital environment, understanding that every patient who enters the hospital must be considered as COVID (+) until proven otherwise.

Prediction and biochemical characterization of intrinsic disorder in the structure of proteolysis-inducing factor/dermcidin

Proteolysis-inducing factor/dermcidin (PIF/DCD) is a novel human gene, located on chromosome 12, locus 12q13.1, that encodes a secreted 110-amino acid protein. Two transcripts for the protein have been identified in normal skin, breast, placenta and brain, and in various primary and metastatic tumor cells. The putative native-state structure of PIF/DCD has not been resolved. Here, we describe some biochemical features of the soluble recombinant 11-kDa protein produced in Escherichia coli. The native 11-kDa polypeptide displayed an anomalous mobility on 1% SDS-PAGE under reduced conditions and appeared as a single ~16-kDa band. Under nonreduced conditions, we detected by mass spectrometry, the presence of multiple peaks corresponding to m/z values of 21 kDa, which we confirmed as a dimeric form with a disulfide bridge between cysteine 34 of each 11-kDa monomer. The native protein exhibited an unusually high susceptibility to proteolytic attack by trypsin, and up to 13 peptides derived from its C-terminus were produced after 5 min of incubation. The secondary structure analysis of PIF/DCD native protein in aqueous solution, by circular dichroism spectroscopy, revealed regions with non-well-defined secondary structure but that acquired á-helix and â-sheet secondary structures in the presence of TFE/water mixtures and micellar and non-micellar SDS molecules. By using PONDR®, DisEMBL™, DisProt, and GlobPlot™ computational predictors, we identified a long disorder region at the N-terminus of PIF/DCD amino acid sequence. This segment (from 19-50 residues) is critical for some of its biological activities, including neuron survival. This result is coherent with successive failure of crystallization of the protein. Taken together, these data suggest that the disorder and order transition may be relevant for some biological functions of PIF/DCD.