Dermotracción por bandas: estudio retrospectivo sobre su efectividad en el cierre diferido de defectos de cobertura en la pierna / Dermatotraction: A retrospective study on its effectiveness in the closure of soft tissue leg defects

Introducción: Una propiedad característica del tegumento humano es la viscoelasticidad. La piel y el tejido celular subcutáneo traccionados por una fuerza constante pueden llegar a cubrir áreas expuestas en lapsos relativamente breves. El objetivo de este estudio fue analizar una serie de casos con defectos de cobertura de la pierna. Se realizó la síntesis tegumentaria con técnica de dermotracción mediante "bandas de tracción", con la finalidad de poder precisar qué lesiones pueden beneficiarse de este método. Materiales y Métodos: Estudio retrospectivo, descriptivo, longitudinal realizado entre 2012 y 2019. Los criterios de inclusión fueron: 1) heridas con déficit de cobertura tegumentaria en la pierna, de etiología traumática diversa (dehiscencia de abordajes quirúrgicos, fasciotomías por síndrome compartimental, fracturas expuestas y heridas abiertas con déficit de partes blandas). Resultados: Se analizó a 36 pacientes (edad promedio 28 años) que tenían lesiones con pérdida de cobertura localizadas en distintas regiones de la pierna. En 27 pacientes (75%), se logró el cierre sin necesidad de procedimientos complementarios. En el 8,3%, se logró la reducción del área expuesta y fue necesario un procedimiento complementario (injerto de piel). Seis pacientes requirieron técnicas reconstructivas de partes blandas miocutáneas y fasciocutáneas. Conclusiones: Esta técnica es efectiva, simple y económica para lograr el cierre diferido de las heridas complejas o fasciotomías. La dermotracción permite el cierre diferido en pocos días luego del trauma. Nivel de Evidencia: IV

Introduction: Viscoelasticity is a distinctive characteristic of the human skin. A constant force pulling on the skin and subcutaneous tissue allows it to cover exposed areas in relatively short periods of time. The objective of this study is to analyze a series of cases with soft tissue leg defects where integumentary closure was accomplished with a skin stretching technique using 'traction bands' in order to determine which injuries can benefit from this treatment. Materials and Methods: This is a retrospective, descriptive, longitudinal study carried out in the period between 2012 and 2019. The inclusion criteria for this study were: 1) wounds with a soft-tissue coverage deficit in the leg of diverse traumatic etiology (surgical wound dehiscence, fasciotomies due to compart-ment syndrome, open fractures, and open wounds with soft tissue deficit). Results: 36 patients (mean age: 28 years) with injuries with loss of coverage in different regions of the leg were analyzed. Closure was achieved in 27 patients (75%), without the need for additional procedures. In three patients (8.3%), the exposed area was reduced, requiring skin grafting as a complementary procedure. Six patients required myocutaneous and fasciocutaneous soft tissue reconstructive procedures. Conclusions: This technique is effective, simple, and economical for closing complex wounds and/or fasciotomies. Dermatotraction allows closure a few days after the trauma. Level of Evidence: IV

Fast Air-to-Liquid Sampler Detects Surges in SARS-CoV-2 Aerosol Levels in Hospital Rooms.

The COVID-19 pandemic highlighted the dangers of airborne pathogen transmission. SARS-CoV-2 is known to be transmitted through aerosols; however, little is known about the dynamics of these aerosols in real environments, the conditions, and the minimum viral load required for infection. Efficiently measuring and capturing pathogens present in the air would help to understand the infection process. Air samplers usually take several hours to obtain an air sample. In this work a fast (1-2 min) method for capturing bioaerosols into a liquid medium has been tested in hospital rooms with COVID-19 patients. This fast sampling allows detecting transient levels of aerosols in the air. SARS-CoV-2 RNA is detected in aerosols from several hospital rooms at different levels. Interestingly, there are sudden boosts of the SARS-CoV-2 load in the air, suggesting that SARS-CoV-2 could be released abundantly at certain moments. These results show that the distribution of SARS-CoV-2-containing aerosols is not homogeneous in the hospital room. This technology is a fast and effective tool for capturing airborne matter in a very short time, which allows for fast decision-making any kind of hazard in the air is detected. It is also useful for a better understanding of aerosols dynamics.

Vibrio cholerae cytolysin is essential for high enterotoxicity and apoptosis induction produced by a cholera toxin gene-negative V. cholerae non-O1, non-O139 strain.

Cholera toxin (CT) gene-negative Vibrio cholerae non-O1, non-O139 strains may cause severe diarrhea though their pathogenic mechanism remains unclear. V. cholerae cytolysin (VCC) is a pore-forming exotoxin encoded in the hlyA gene of V. cholerae whose contribution to the pathogenesis is not fully understood. In this work, the virulence properties of a CT gene-negative V. cholerae non-O1, non-O139 strain causing a cholera-like syndrome were analyzed. Inoculation of rabbit ileal loops with the wild type strain induced extensive fluid accumulation, accompanied by severe histopathological damage characterized by villus shortening, lymphangiectasia and focal areas of necrosis. These pathogenic effects were abrogated by mutation of the hlyA gene thus pointing out the main role of VCC in the virulence of the strain. Interestingly, this toxin was capable of triggering apoptosis in human intestinal cell lines due to its anion channel activity. Moreover, the wild type strain also induced increased apoptosis of the intestinal epithelium cells which was not observed upon inoculation of the VCC null mutant strain, indicating that VCC may trigger apoptotic cell death during infection in vivo. Altogether, these results support a main role of VCC in the pathogenesis of the CT gene-negative V. cholerae non-O1, non-O139 strain and identify apoptosis as a previously unrecognized cell death pathway triggered by VCC.