Ecología de especies de Candida encontrada en diversas áreas del Departamento de Pediatría del Hospital Escuela Universitario Tegucigalpa, Honduras

In the last 45 years, there has been a significant increase in Candida infections among the general population, reported as the fourth cause of nosocomial blood infections (1). These infections have been observed more frequently in critically ill patients. Identification of Candida species is necessary because, among strains, different patterns of natural resistance to antifungal drugs are present. This resistance could disrupt the effectiveness of the treatment, thus increasing hospital stay and mortality among critically ill patients. To determine the ecology of Candida species found in different areas of the Departmentof Pediatrics of HEU in 55 Candida-positive cultures from different types of pediatric samples using germ-tube, CHROmagar and PCR-RFLP, Implementing the latter technique as a diagnostic method. The general prevalence of Candida within the areas of the Department of Pediatrics of the HEU using PCR-RFLP as a gold standard was C. tropicalis 25.5%, C.albicans 21.8%, C. parapsilosis 12.7%. C. glabrata con 7.3% and C. Krusei 5.5%. A higher percentage of positivity was observed in Pediatric Oncology Room 12 (21.8%), followed by Nutrition Room 12 (21.8%) and Infants Room 10 (18.2%). The most frequent type of sample was urine with 31 isolates (56.4%). The PCR-RFLP method is a valuable tool for the identification of species causing infection and differentiates between co-infections among Candida species. This characteristic of the PCR-RFLP method evidenced that this is a fast and useful method in the treatment, prophylaxis, and in the design of strategies of reduction of mortality by this genre.En los últimos 45 años se ha descrito un aumento importante de infecciones por el género Candida entre la población general, reportándose como la cuarta causa de infecciones sanguíneas de origen nosocomial(1). Estas infecciones han sido observadas con más frecuencia en pacientes en estado crítico. La identificación de especies de Candida es necesaria debido a que, entre cepas se presentan patrones diferentes de resistencia natural hacia los fármacos antifúngicos. Este grado de resistencia podría inhabilitar la efectividad del tratamiento aumentando así la estancia hospitalaria y la mortalidad entre pacientes en estado crítico. Determinar la ecología de especies de Candida encontrada en diversas áreas del Departamento de Pediatría del HEU en 55 cultivos positivos por Candida, provenientes de diferentes tipos de muestras de pacientes pediátricos mediante las técnicas de Tubo germinal, CHROmagar y PCR-RFLP, implementando esta última técnica como método diagnóstico. La prevalencia general dentro de las áreas del Departamento de Pediatría del HEU de especies de Candida, tomando en cuenta la PCR-RFLP como gold standard en orden de frecuencia descendente, fue C. tropicalis con un 25.5%, C.albicans con 21.8%, C. parapsilosis con 12.7%. C. glabrata con 7.3%, y C. Krusei con un 5.5%. Se encontró que la mayoría de los cultivos positivos provenían de la Sala de Oncología Pediátrica 12 (21.8%), seguido por la sala de Nutrición 12 (21.8%) y sala de Lactantes 10 (18.2%). El tipo de muestra con positividad más frecuente fuela de orina con 31 aislamientos (56.4%). El método de PCR-RFLP resultó ser una herramienta valiosa para la identificación de especies de Candida y en la discriminación de co-infecciones entre estas especies. Las características del método de PCR-RFLP evidencia que es un método rápido y útil en el tratamiento, profilaxis, y en diseños de estrategias de reducción de mortalidad por este género.&nbsp

Development and benchmark to obtain AMBER parameters dataset for non-standard amino acids modified with 4-hydroxy-2-nonenal

The data described here support the research article “4-HNE carbonylation induces local conformational changes on bovine serum albumin and thioredoxin. A molecular dynamics study” (Alviz-Amador et al., 2018) . Dataset on Gaff force field parameters of AMBER is provided for assembled three non-standard amino acids resulting of the 4-HNE Michael addition, the main end product of lipids peroxidation. Data include a framework for derivation of missing bonds, angles and dihedral parameters for Cys, His, and Lys modified amino acids, alongside optimized partial charges derived with Restrained Electrostatic Potential (RESP) method and the new force field parameters obtained by quantic mechanical (QM) using HF/6-31G** level of theory. Benchmark as a graphics tutorial summary steps to obtained new parameters and the validation of non-standard amino acids is presented. The new residues constructed are put available to the scientific community to perform molecular dynamics simulations of modified 4-HNE proteins. Keywords: AMBER, Gaff, Force field parameterization, Mechanical quantic, Molecular dynamics, Geometry optimization, Validatio

Differential Impact of CD43 and CD28 on T-Cell Differentiation Depending on the Order of Engagement with the TCR

The combination of signals from the T-cell receptor (TCR) and co-stimulatory molecules triggers transcriptional programs that lead to proliferation, cytokine secretion, and effector functions. We compared the impact of engaging the TCR with CD28 and/or CD43 at different time points relative to TCR engagement on T-cell function. TCR and CD43 simultaneous engagement resulted in higher CD69 and PD-1 expression levels than in TCR and CD28-stimulated cells, with a cytokine signature of mostly effector, inflammatory, and regulatory cytokines, while TCR and CD28-activated cells secreted all categories of cytokines, including stimulatory cytokines. Furthermore, the timing of CD43 engagement relative to TCR ligation, and to a lesser degree that of CD28, resulted in distinct patterns of expression of cytokines, chemokines, and growth factors. Complete cell activation was observed when CD28 or CD43 were engaged simultaneously with or before the TCR, but ligating the TCR before CD43 or CD28 failed to complete a cell activation program regarding cytokine secretion. As the order in which CD43 or CD28 and the TCR were engaged resulted in different combinations of cytokines that shape distinct T-cell immune programs, we analyzed their upstream sequences to assess whether the combinations of cytokines were associated with different sets of regulatory elements. We found that the order in which the TCR and CD28 or CD43 are engaged predicts the recruitment of specific sets of chromatin remodelers and TFSS, which ultimately regulate T-cell polarization and plasticity. Our data underscore that the combination of co-stimulatory molecules and the time when they are engaged relative to the TCR can change the cell differentiation program

Memorias del primer Simposio Nacional de Ciencias Agronómicas

Primer simposio nacional de Ciencias Agronómicas: El renacer del espacio de discusión científica para el Agro colombiano

Memorias del primer Simposio Nacional de Ciencias Agronómicas

Primer simposio nacional de Ciencias Agronómicas: El renacer del espacio de discusión científica para el Agro colombiano

Risk of COVID-19 after natural infection or vaccinationResearch in context

Summary: Background: While vaccines have established utility against COVID-19, phase 3 efficacy studies have generally not comprehensively evaluated protection provided by previous infection or hybrid immunity (previous infection plus vaccination). Individual patient data from US government-supported harmonized vaccine trials provide an unprecedented sample population to address this issue. We characterized the protective efficacy of previous SARS-CoV-2 infection and hybrid immunity against COVID-19 early in the pandemic over three-to six-month follow-up and compared with vaccine-associated protection. Methods: In this post-hoc cross-protocol analysis of the Moderna, AstraZeneca, Janssen, and Novavax COVID-19 vaccine clinical trials, we allocated participants into four groups based on previous-infection status at enrolment and treatment: no previous infection/placebo; previous infection/placebo; no previous infection/vaccine; and previous infection/vaccine. The main outcome was RT-PCR-confirmed COVID-19 >7–15 days (per original protocols) after final study injection. We calculated crude and adjusted efficacy measures. Findings: Previous infection/placebo participants had a 92% decreased risk of future COVID-19 compared to no previous infection/placebo participants (overall hazard ratio [HR] ratio: 0.08; 95% CI: 0.05–0.13). Among single-dose Janssen participants, hybrid immunity conferred greater protection than vaccine alone (HR: 0.03; 95% CI: 0.01–0.10). Too few infections were observed to draw statistical inferences comparing hybrid immunity to vaccine alone for other trials. Vaccination, previous infection, and hybrid immunity all provided near-complete protection against severe disease. Interpretation: Previous infection, any hybrid immunity, and two-dose vaccination all provided substantial protection against symptomatic and severe COVID-19 through the early Delta period. Thus, as a surrogate for natural infection, vaccination remains the safest approach to protection. Funding: National Institutes of Health

Risk of COVID-19 after natural infection or vaccinationResearch in context

Background: While vaccines have established utility against COVID-19, phase 3 efficacy studies have generally not comprehensively evaluated protection provided by previous infection or hybrid immunity (previous infection plus vaccination). Individual patient data from US government-supported harmonized vaccine trials provide an unprecedented sample population to address this issue. We characterized the protective efficacy of previous SARS-CoV-2 infection and hybrid immunity against COVID-19 early in the pandemic over three-to six-month follow-up and compared with vaccine-associated protection. Methods: In this post-hoc cross-protocol analysis of the Moderna, AstraZeneca, Janssen, and Novavax COVID-19 vaccine clinical trials, we allocated participants into four groups based on previous-infection status at enrolment and treatment: no previous infection/placebo; previous infection/placebo; no previous infection/vaccine; and previous infection/vaccine. The main outcome was RT-PCR-confirmed COVID-19 >7–15 days (per original protocols) after final study injection. We calculated crude and adjusted efficacy measures. Findings: Previous infection/placebo participants had a 92% decreased risk of future COVID-19 compared to no previous infection/placebo participants (overall hazard ratio [HR] ratio: 0.08; 95% CI: 0.05–0.13). Among single-dose Janssen participants, hybrid immunity conferred greater protection than vaccine alone (HR: 0.03; 95% CI: 0.01–0.10). Too few infections were observed to draw statistical inferences comparing hybrid immunity to vaccine alone for other trials. Vaccination, previous infection, and hybrid immunity all provided near-complete protection against severe disease. Interpretation: Previous infection, any hybrid immunity, and two-dose vaccination all provided substantial protection against symptomatic and severe COVID-19 through the early Delta period. Thus, as a surrogate for natural infection, vaccination remains the safest approach to protection. Funding: National Institutes of Health