Efecto antimicrobiano de Myrciaria dubia “camu camu” sobre Pseudomonas aeruginosa resistente a carbapenémicos

Demostrar el efecto antimicrobiano de cuatro concentraciones de Myrciaria dubia “Camu camu” sobre“Pseudomonas aeruginosa resistente a carbapenémicos. Métodos. Elaboramos extracto etanólico de cáscara de Myrciaria dubia en las siguientes concentraciones: 250 mg/mL, 500 mg/mL, 750mg/ml y 1000 mg/ml. Para estimar su actividad antimicrobiana se usó el método de difusión en disco (Kirby Bauer). En cuanto al efecto bactericida, se determinó mediante el conteo de UFC y también determinamos la CMI, hallada mediante la absorbancia por espectrofotometría. Tuvimos tres grupos control, uno con gentamicina, con etanol de 70° y un grupo solo con el inóculo de bacterias. Se llevó a cabo 10 repeticiones en cada caso. Resultados. Estadísticamente se determinó que había diferencia significativa entre las concentraciones del extracto etanólico de Myrciaria dubia contra Pseudomonas aeruginosa resistente a carbapenémicos. Los resultados se consideraron como significativos si el valor-p < 0,05. Hubo sensibilidad a las cuatro concentraciones al medir los halos de inhibición y compararlos de acuerdo a la escala Duraffourd. La CMB fue la de 1000 mg/ml. En cuanto a la CMI, la absorbancia máxima fue de 0.83A a la concentración de 1000 mg/ml. Conclusión. Myrciaria dubia “camu camu” tiene efecto inhibitorio in vitro contra Pseudomonas aeruginosa resistente a carbapenémicos.Prove the antimicrobial effect of four concentrations of Myrciaria dubia ""Camu camu"" on ""Pseudomonas aeruginosa carbapenems resistant. Methods. We elaborate ethanolic extract of Myrciaria dubia husk in the following concentrations: 250 mg / mL, 500 mg / mL, 750mg / ml and 1000 mg / ml. The disk diffusion method (Kirby Bauer) was used to estimate its antimicrobial activity. As for the bactericidal effect, it was determined by the CFU count and we also determined the MIC, found by the absorbance by spectrophotometry. We had three control groups, one with gentamicin, with 70 ° ethanol and one group only with the bacteria inoculum. 10 repetitions were carried out in each case. Results. Statistically it was determined that there was a significant difference between the concentrations of ethanol extract of Myrciaria dubia against Pseudomonas aeruginosa carbapenems resistant. The results were considered significant if the p-value <0.05. There was sensitivity to the four concentrations of said extract by measuring the inhibition halos and comparing them according as Duraffourd scale. The MBC was 1000 mg / ml. As for the MIC, the maximum absorbance was 0.83A at the concentration of 1000 mg / ml. Conclusion. Myrciaria dubia ""camu camu"" has in vitro inhibitory effect against Pseudomonas aeruginosa carbapenems resistant.Tesi

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