Development of a Bmi1+ Cardiac Mouse Progenitor Immortalized Model to Unravel the Relationship with Its Protective Vascular Endothelial Niche.

The adult mammalian heart has been demonstrated to be endowed with low but real turnover capacity, especially for cardiomyocytes, the key functional cell type. The source, however, of that turnover capacity remains controversial. In this regard, we have defined and characterized a resident multipotent cardiac mouse progenitor population, Bmi1+DR (for Bmi1+ Damage-Responsive cells). Bmi1+DR is one of the cell types with the lowest ROS (Reactive Oxygen Species) levels in the adult heart, being particularly characterized by their close relationship with cardiac vessels, most probably involved in the regulation of proliferation/maintenance of Bmi1+DR. This was proposed to work as their endothelial niche. Due to the scarcity of Bmi1+DR cells in the adult mouse heart, we have generated an immortalization/dis-immortalization model using Simian Vacuolating Virus 40-Large Antigen T (SV40-T) to facilitate their in vitro characterization. We have obtained a heterogeneous population of immortalized Bmi1+DR cells (Bmi1+DRIMM) that was validated attending to different criteria, also showing a comparable sensitivity to strong oxidative damage. Then, we concluded that the Bmi1-DRIMM population is an appropriate model for primary Bmi1+DR in vitro studies. The co-culture of Bmi1+DRIMM cells with endothelial cells protects them against oxidative damage, showing a moderate depletion in non-canonical autophagy and also contributing with a modest metabolic regulation.

Caracterización de la enfermedad de Kawasaki en niños entre 3 meses y 15 años en 2 instituciones de salud en Bogotá, Colombia / Characterization of Kawasaki disease in children between 3 months and 15 years in 2 health institutions in Bogotá, Colombia

Resumen Objetivo: Disminuir la brecha del conocimiento de la Enfermedad de Kawasaki (EK) y dar herramientas al personal médico por medio de la descripción de la demografía, presentación clínica, los hallazgos de laboratorio, la frecuencia de lesiones coronarias y desenlaces en 2 instituciones de salud en Bogotá, Colombia. Metodología: Estudio observacional retrospectivo mediante la revisión de historias clínicas de los códigos CIE-10 de paciente pediátricos donde se evaluaron características demográficas, presentación clínica, datos paraclínicos (incluidos hallazgos ecocardiográficos), tratamiento recibido y respuesta a este, en pacientes admitidos entre junio de 2015 y junio de 2020. Resultados: Se incluyeron 36 pacientes entre 3 meses y 15 años. La edad media de los pacientes fue de 2.9 años, siendo la EK más frecuente en niños en una rela ción 2:1. El 61.1% presentó EK completa o clásica, el 30.5% EK incompleta y el 8.3% EK atípica. Todos los pacientes recibieron inmunoglobulina intravenosa antes del día 10 del curso de la enfermedad, con remisión de la fiebre antes de 12 horas luego de la administración. La incidencia de compromiso coronario fue de 30.6%. Conclusiones: La Enfermedad de Kawasaki tiene un curso clínico característico que afecta especialmente a niños menores de 5 años. Es una entidad clínica que, al ser reconocida con mayor frecuencia por pediatras, permite instaurar diagnóstico y tratamiento tempranos evitando complicaciones y secuelas a mediano y largo plazo.

Abstract Objective: To reduce the knowledge gap about Kawasaki Disease (KD) and to provide tools to medical personnel through the description of demographics, clinical presentation, laboratory findings, frequency of coronary lesions and outcomes in 2 health institutions in Bogota Colombia. Methodology: Retrospective observational study by reviewing the clinical records of the ICD-10 codes of pediatric patients where demographic characteristics, clinical presentation, paraclinical data (including echocardiographic findings), treatment received and response to it were evaluated, in patients admitted between June 2015 and June 2020. Results: The mean age of the patients was 2.9 years, being KD more frequent in boys a 2:1 ratio. 61.1% had complete or classic KD, 30.5% had incomplete KD, and 8.3% atypical KD. All patients received intravenous immunoglobulin before day 10 of the course of the disease, with remission of fever within 12 hours after administration. The incidence of coronary compromise was 30.6%. Conclusions: KD has a characteristic clinical course that especially affects children under 5 years. A more frequent recognition of this clinical entity by pediatricians, allows for an early diagnosis and treatment avoiding complications and sequelae in the medium and long term.

Correlation between Arterial Lactate and Central Venous Lactate in Children with Sepsis.

Introduction. Lactate is an important indicator of tissue perfusion. The objective of this study is to evaluate if there are significant differences between the arterial and central venous measurement of lactate in pediatric patients with sepsis and/or septic shock. Methods. Longitudinal retrospective observational study. Forty-two patients were included between the age of 1 month and 17 years, with a diagnosis of sepsis and septic shock, who were admitted to the intensive care unit of a university referral hospital. The lactate value obtained from an arterial blood sample and a central venous blood sample drawn simultaneously, and within 24 hours of admission to the unit, was recorded. Results. The median age was 2.3 years (RIC 0,3-15), with a predominance of males (71.4%), having a 2.5 : 1 ratio to females. Most of the patients had septic shock (78.5%) of pulmonary origin (50.0%), followed by those of gastrointestinal origin (26.1%). Using Spearman's Rho, a 0.872 (p < 0.001) correlation was found between arterial and venous lactate, which did not vary when adjusted for age (p < 0.05) and the use of vasoactive drugs (p < 0.05). Conclusion. There is a good correlation between arterial and venous lactate in pediatric patients with sepsis and septic shock, which is not affected by demographic variables or type of vasoactive support.