Two-positron-bonded dihalides: Ps2XY (X,Y=F,Cl,Br).

This study explores the energetic stability and physical prop-This study explores the energetic stability and physical properties of Ps2XY complexes formed by two halide anions (X-,Y-=F-,X-,Br-), and two positrons (Ps:positron-electron pair). We combine electronic coupled cluster (CCSD(T)) calculations with positronic multicomponent renormalized partial third-order propagator (MC-REN-PP3) calculations to effectively recover correlation energies. Analysis of potential energy curves confirms the energetic stability of these positronic molecules, with optimized structures identified as global minima. Further investigation of electron and positron densities reveals stabilization owing to the formation of two-positron bonds. The global stability of the Ps2XY complexes contrasts with the metastable two-positron-bonded (PsH)2, which energetically favors the emission of Ps2. Comparative analysis of one- and two-positron dihalides indicates that adding a positron to PsXY- generally results in shorter bond distances, higher force constants, and lower dissociation energies, with exceptions due to differences in positron affinities of PsXY- and Y-. We explore the analogy between two-positron-bonded dihalide systems Ps2XY and two-electron-bonded dialkali molecules AB, (A,B=Na,K,Rb). The bonding properties in positron dihalides and their electronic dialkali analogs display identical periodic trends. However, compared to their isoelectronic AB counterparts, the positron bonds in Ps2XY have shorter bond lengths, higher force constants, and higher bond energies.

A novel viral RNA detection method based on the combined use of trans-acting ribozymes and HCR-FRET analyses.

The diagnoses of retroviruses are essential for controlling the rapid spread of pandemics. However, the real-time Reverse Transcriptase quantitative Polymerase Chain Reaction (RT-qPCR), which has been the gold standard for identifying viruses such as SARS-CoV-2 in the early stages of infection, is associated with high costs and logistical challenges. To innovate in viral RNA detection a novel molecular approach for detecting SARS-CoV-2 viral RNA, as a proof of concept, was developed. This method combines specific viral gene analysis, trans-acting ribozymes, and Fluorescence Resonance Energy Transfer (FRET)-based hybridization of fluorescent DNA hairpins. In this molecular mechanism, SARS-CoV-2 RNA is specifically recognized and cleaved by ribozymes, releasing an initiator fragment that triggers a hybridization chain reaction (HCR) with DNA hairpins containing fluorophores, leading to a FRET process. A consensus SARS-CoV-2 RNA target sequence was identified, and specific ribozymes were designed and transcribed in vitro to cleave the viral RNA into fragments. DNA hairpins labeled with Cy3/Cy5 fluorophores were then designed and synthesized for HCR-FRET assays targeting the RNA fragment sequences resulting from ribozyme cleavage. The results demonstrated that two of the three designed ribozymes effectively cleaved the target RNA within 10 minutes. Additionally, DNA hairpins labeled with Cy3/Cy5 pairs efficiently detected target RNA specifically and triggered detectable HCR-FRET reactions. This method is versatile and can be adapted for use with other viruses. Furthermore, the design and construction of a DIY photo-fluorometer prototype enabled us to explore the development of a simple and cost-effective point-of-care detection method based on digital image analysis.

Diabetes tipo 1 en pediatría durante la pandemia por COVID-19: tiempo de evolución de síntomas y formas de presentación en un centro de referencia / Type 1 diabetes in pediatrics during the COVID-19 pandemic: Time from symptom onset and forms of presentation at a referral hospital

Introducción. La pandemia por COVID-19 afectó la atención de pacientes con diabetes mellitus tipo 1 (DM1). Además, se reportó un aumento de cetoacidosis diabética (CAD) como forma de diagnóstico. Objetivos. Evaluar si durante la pandemia por COVID-19 se modificaron el tiempo de evolución de síntomas, las causas de hospitalización por DM1 y la proporción de formas graves, y describir la infección por SARS-CoV-2 en estos pacientes. Población y métodos. Estudio transversal que incluyó pacientes menores de 19 años hospitalizados por DM1 en un centro pediátrico de referencia de marzo de 2018 a agosto de 2019 (prepandemia) y de marzo de 2020 a agosto de 2021 (pandemia). Resultados. Se analizaron 231 internaciones, 135 prepandemia y 96 en pandemia. Los pacientes con debut diabético presentaron menor tiempo de evolución de síntomas en pandemia que en prepandemia (18,8 ± 10,2 vs. 52,1 ±12,1 días, respectivamente; p <0,001). Las hospitalizaciones por todas las formas de debut diabético y el debut con CAD fueron más frecuentes en pandemia que en prepandemia (59,4 % vs. 39,3 %; OR 2,3; IC95% 1,3-3,8; p = 0,003); y (40,6 % vs. 20,7 %; OR 2,6; IC95% 1,4-5,2; p = 0,006) respectivamente. La proporción de formas graves de CAD no se modificó entre ambos períodos (48,1 % vs. 59,9 %; p = 0,3). Solo 6 pacientes presentaron infección por SARS-CoV-2; 3 fueron formas graves. Conclusión. Durante la pandemia, disminuyó el tiempo de evolución de síntomas y aumentó la frecuencia de hospitalizaciones por debut de DM1, con mayor proporción de CAD. No se modificó la proporción de formas graves de CAD

Introduction. The COVID-19 pandemic impacted on the health care of patients with type 1 diabetes mellitus (DM1). An increase in diabetic ketoacidosis (DKA) as a form of diagnosis was reported. Objectives. To assess whether there were changes in the time from symptom onset, the causes of hospitalization due to DM1, and the proportion of severe forms, and to describe SARS-CoV-2 infection in these patients. Population and methods. Cross-sectional study in patients younger than 19 years hospitalized due to DM1 from March 2018 to August 2019 (pre-pandemic) and from March 2020 to August 2021 (pandemic). Results. The assessment included 135 hospitalizations in the pre-pandemic period and 96 during the pandemic. The time from symptom onset during the pandemic in those with debutof diabetes was shorter than in the pre-pandemic period (18.8 ± 10.2 versus 52.1 ± 12.1 days, respectively; p < 0.001). Hospitalizations due to all forms of diabetes debut and debut with DKA were more common during the pandemic than before it (59.4% versus 39.3%; odds ratio [OR]: 2.3; 95% confidence interval [CI]: 1.3­3.8; p = 0.003 and 40.6% versus 20.7%; OR: 2.6; 95% CI: 1.4­5.2; p = 0.006, respectively). Severe forms of DKA did not change between both periods (48.1% versus 59.9%; p = 0.3). Only 6 patients developed SARS-CoV-2 infection; 3 were severe. Conclusion. During the pandemic, the time from symptom onset decreased and the frequency of hospitalizations due to debut of DM1 increased. The proportion of severe forms of DKA did not change.

Applications of the Methylotrophic Yeast Komagataella phaffii in the Context of Modern Biotechnology.

Komagataella phaffii (formerly Pichia pastoris) is a methylotrophic yeast widely used in laboratories around the world to produce recombinant proteins. Given its advantageous features, it has also gained much interest in the context of modern biotechnology. In this review, we present the utilization of K. phaffii as a platform to produce several products of economic interest such as biopharmaceuticals, renewable chemicals, fuels, biomaterials, and food/feed products. Finally, we present synthetic biology approaches currently used for strain engineering, aiming at the production of new bioproducts.

Recent Progress in Polysaccharide-Based Materials for Energy Applications: A Review.

In recent years, polysaccharides have emerged as a promising alternative for the development of environmentally friendly materials. Polysaccharide-based materials have been mainly studied for applications in the food, packaging, and biomedical industries. However, many investigations report processing routes and treatments that enable the modification of the inherent properties of polysaccharides, making them useful as materials for energy applications. The control of the ionic and electronic conductivities of polysaccharide-based materials allows for the development of solid electrolytes and electrodes. The incorporation of conductive and semiconductive phases can modify the permittivities of polysaccharides, increasing their capacity for charge storage, making them useful as active surfaces of energy harvesting devices such as triboelectric nanogenerators. Polysaccharides are inexpensive and abundant and could be considered as a suitable option for the development and improvement of energy devices. This review provides an overview of the main research work related to the use of both common commercially available polysaccharides and local native polysaccharides, including starch, chitosan, carrageenan, ulvan, agar, and bacterial cellulose. Solid and gel electrolytes derived from polysaccharides show a wide range of ionic conductivities from 0.0173 × 10-3 to 80.9 × 10-3 S cm-1. Electrodes made from polysaccharides show good specific capacitances ranging from 8 to 753 F g-1 and current densities from 0.05 to 5 A g-1. Active surfaces based on polysaccharides show promising results with power densities ranging from 0.15 to 16 100 mW m-2. These investigations suggest that in the future polysaccharides could become suitable materials to replace some synthetic polymers used in the fabrication of energy storage devices, including batteries, supercapacitors, and energy harvesting devices.

Type 1 diabetes in pediatrics during the COVID-19 pandemic: Time from symptom onset and forms of presentation at a referral hospital. / Diabetes tipo 1 en pediatría durante la pandemia por COVID-19: tiempo de evolución de síntomas y formas de presentación en un centro de referencia.

Introduction. The COVID-19 pandemic impacted on the health care of patients with type 1 diabetes mellitus (DM1). An increase in diabetic ketoacidosis (DKA) as a form of diagnosis was reported. Objectives. To assess whether there were changes in the time from symptom onset, the causes of hospitalization due to DM1, and the proportion of severe forms, and to describe SARS-CoV-2 infection in these patients. Population and methods. Cross-sectional study in patients younger than 19 years hospitalized due to DM1 from March 2018 to August 2019 (pre-pandemic) and from March 2020 to August 2021 (pandemic). Results. The assessment included 135 hospitalizations in the pre-pandemic period and 96 during the pandemic. The time from symptom onset during the pandemic in those with debut of diabetes was shorter than in the pre-pandemic period (18.8 ± 10.2 versus 52.1 ± 12.1 days, respectively; p < 0.001). Hospitalizations due to all forms of diabetes debut and debut with DKA were more common during the pandemic than before it (59.4% versus 39.3%; odds ratio [OR]: 2.3; 95% confidence interval [CI]: 1.3-3.8; p = 0.003 and 40.6% versus 20.7%; OR: 2.6; 95% CI: 1.4-5.2; p = 0.006, respectively). Severe forms of DKA did not change between both periods (48.1% versus 59.9%; p = 0.3). Only 6 patients developed SARS-CoV-2 infection; 3 were severe. Conclusion. During the pandemic, the time from symptom onset decreased and the frequency of hospitalizations due to debut of DM1 increased. The proportion of severe forms of DKA did not change.

Introducción. La pandemia por COVID-19 afectó la atención de pacientes con diabetes mellitus tipo 1 (DM1). Además, se reportó un aumento de cetoacidosis diabética (CAD) como forma de diagnóstico. Objetivos. Evaluar si durante la pandemia por COVID-19 se modificaron el tiempo de evolución de síntomas, las causas de hospitalización por DM1 y la proporción de formas graves, y describir la infección por SARS-CoV-2 en estos pacientes. Población y métodos. Estudio transversal que incluyó pacientes menores de 19 años hospitalizados por DM1 en un centro pediátrico de referencia de marzo de 2018 a agosto de 2019 (prepandemia) y de marzo de 2020 a agosto de 2021 (pandemia). Resultados. Se analizaron 231 internaciones, 135 prepandemia y 96 en pandemia. Los pacientes con debut diabético presentaron menor tiempo de evolución de síntomas en pandemia que en prepandemia (18,8 ± 10,2 vs. 52,1 ±12,1 días, respectivamente; p <0,001). Las hospitalizaciones por todas las formas de debut diabético y el debut con CAD fueron más frecuentes en pandemia que en prepandemia (59,4 % vs. 39,3 %; OR 2,3; IC95% 1,3-3,8; p = 0,003); y (40,6 % vs. 20,7 %; OR 2,6; IC95% 1,4-5,2; p = 0,006) respectivamente. La proporción de formas graves de CAD no se modificó entre ambos períodos (48,1 % vs. 59,9 %; p = 0,3). Solo 6 pacientes presentaron infección por SARS-CoV-2; 3 fueron formas graves. Conclusión. Durante la pandemia, disminuyó el tiempo de evolución de síntomas y aumentó la frecuencia de hospitalizaciones por debut de DM1, con mayor proporción de CAD. No se modificó la proporción de formas graves de CAD.

Impacto de la pandemia por SARS-CoV-2 en el índice de masa corporal de niños asistidos en la Ciudad Autónoma de Buenos Aires / Impact of the SARS-CoV-2 pandemic on the body mass index of children seen in the City of Buenos Aires

Introducción. El sobrepeso y la obesidad infantil constituyen un problema de salud pública. El inicio de la pandemia por COVID-19 pudo haber favorecido esta patología. El puntaje Z del índice de masa corporal (Z-IMC) es un indicador aceptado para su diagnóstico y seguimiento. Objetivo. Evaluar si la prevalencia de sobrepeso y obesidad, y el Z-IMC en niños de 2 a 5 años aumentó durante la pandemia. Población y métodos. Estudio de cohorte retrospectiva. Se incluyeron pacientes asistidos en efectores públicos de salud del Gobierno de la Ciudad Autónoma de Buenos Aires (GCABA), de 2 a 5 años de edad, con registro de peso y talla en dos consultas, antes y después de haber comenzado el aislamiento social preventivo y obligatorio (ASPO). Se registró estado nutricional (Z-IMC) y variación del Z-IMC entre ambas consultas. Resultados. Se evaluaron 3866 sujetos, edad promedio 3,4 ± 0,8 años; el 48,1 % fueron mujeres. El intervalo promedio entre consultas fue 14,3 ± 2,5 meses. La prevalencia de sobrepeso/obesidad aumentó del 12,6 % (IC95% 11,6-13,6) al 20,9 % (IC95% 19,6-22-2); p <0,001, al igual que el Z-IMC (0,4 ± 1,1 vs. 0,8 ± 1,3; p <0,001). Conclusión. La prevalencia de sobrepeso y obesidad, y el Z-IMC en niños de 2 a 5 años aumentó significativamente durante la pandemia.

Introduction. Childhood overweight and obesity are a public health problem. The onset of the COVID-19 pandemic may have contributed to this condition. The body mass index (BMI) Z-score has been accepted as an indicator for overweight and obesity diagnosis and follow-up. Objective. To assess whether the prevalence of overweight and obesity and the BMI Z-score in children aged 2 to 5 years increased during the pandemic. Population and methods. Retrospective, cohort study. Patients included were those seen at public health care facilities in the City of Buenos Aires (CABA), who were aged 2 to 5 years, had weight and height values recorded at 2 different visits, before and after the establishment of the preventive and mandatory social isolation policy. Patients' nutritional status (BMI Z-score) and the variation in this indicator between both visits were recorded. Results. A total of 3866 subjects were assessed; their average age was 3.4 ± 0.8 years; 48.1% were girls. The average interval between both visits was 14.3 ± 2.5 months. The prevalence of overweight/ obesity increased from 12.6% (95% CI: 11.6­13.6) to 20.9% (95% CI: 19.6­22.2), p < 0.001, and so did the BMI Z-score (0.4 ± 1.1 versus 0.8 ± 1.3, p < 0.001). Conclusion. The prevalence of overweight and obesity and the BMI Z-score in children aged 2 to 5 years increased significantly during the pandemic.

Impact of the SARS-CoV-2 pandemic on the body mass index of children seen in the City of Buenos Aires. / Impacto de la pandemia por SARS-CoV-2 en el índice de masa corporal de niños asistidos en la Ciudad Autónoma de Buenos Aires.

Introduction. Childhood overweight and obesity are a public health problem. The onset of the COVID-19 pandemic may have contributed to this condition. The body mass index (BMI) Z-score has been accepted as an indicator for overweight and obesity diagnosis and follow-up. Objective. To assess whether the prevalence of overweight and obesity and the BMI Z-score in children aged 2 to 5 years increased during the pandemic. Population and methods. Retrospective, cohort study. Patients included were those seen at public health care facilities in the City of Buenos Aires (CABA), who were aged 2 to 5 years, had weight and height values recorded at 2 different visits, before and after the establishment of the preventive and mandatory social isolation policy. Patients' nutritional status (BMI Z-score) and the variation in this indicator between both visits were recorded. Results. A total of 3866 subjects were assessed; their average age was 3.4 ± 0.8 years; 48.1% were girls. The average interval between both visits was 14.3 ± 2.5 months. The prevalence of overweight/ obesity increased from 12.6% (95% CI: 11.6-13.6) to 20.9% (95% CI: 19.6-22.2), p < 0.001, and so did the BMI Z-score (0.4 ± 1.1 versus 0.8 ± 1.3, p < 0.001). Conclusion. The prevalence of overweight and obesity and the BMI Z-score in children aged 2 to 5 years increased significantly during the pandemic.

Introducción. El sobrepeso y la obesidad infantil constituyen un problema de salud pública. El inicio de la pandemia por COVID-19 pudo haber favorecido esta patología. El puntaje Z del índice de masa corporal (Z-IMC) es un indicador aceptado para su diagnóstico y seguimiento. Objetivo. Evaluar si la prevalencia de sobrepeso y obesidad, y el Z-IMC en niños de 2 a 5 años aumentó durante la pandemia. Población y métodos. Estudio de cohorte retrospectiva. Se incluyeron pacientes asistidos en efectores públicos de salud del Gobierno de la Ciudad Autónoma de Buenos Aires (GCABA), de 2 a 5 años de edad, con registro de peso y talla en dos consultas, antes y después de haber comenzado el aislamiento social preventivo y obligatorio (ASPO). Se registró estado nutricional (Z-IMC) y variación del Z-IMC entre ambas consultas. Resultados. Se evaluaron 3866 sujetos, edad promedio 3,4 ± 0,8 años; el 48,1 % fueron mujeres. El intervalo promedio entre consultas fue 14,3 ± 2,5 meses. La prevalencia de sobrepeso/obesidad aumentó del 12,6 % (IC95% 11,6-13,6) al 20,9 % (IC95% 19,6-22-2); p <0,001, al igual que el Z-IMC (0,4 ± 1,1 vs. 0,8 ± 1,3; p <0,001). Conclusión. La prevalencia de sobrepeso y obesidad, y el Z-IMC en niños de 2 a 5 años aumentó significativamente durante la pandemia.

Analysis of the effectiveness coefficient in greco-roman fighting athletes at different levels of competition / Análisis del coeficiente de eficacia en atletas de lucha griego-romana en distintos niveles de competición / Análise do coeficiente de efetividade em atletas de luta greco-romana em diferentes níveis de competição

ABSTRACT Introduction: Wrestling is an ancient combat sport, individual and of complex performance, which integrates high technical and tactical complexity, associated with a bioenergetic interaction and a high coordinative pattern. In Brazil, the number of competitors at different levels has increased significantly in the last years, evidencing the need to search for answers that can help coaches in the different situations of the competitive calendar. The prescription of the means and methods of training in Greco-Roman wrestling aims at the development of the technical effectiveness. However, there is no evidence of indicators of technical effectiveness, in Brazilian elite athletes of Greco-Roman wrestling, in national and international competitions. Objectives: The objective of the study was to verify and to compare the technical effectiveness of the wrestlers of Greco-Roman fight of the Brazilian selection, in two competitions: one in the national level and the other international. Methods: Seven athletes of the Brazilian wrestling team participated of the investigation (age: 25±5 years; stature: 175±12 cm; corporal mass: 80± 21kg). Analysis of the effective, not effective and total technique were accomplished. After identifying the normality of the data (SHAPIRO WILKS), the Student's t test was used to compare the variables, according to the moment evaluated, considering the significance level of 5%. Results: The results showed a significant decrease (p = 0.03) in the standing effective technique and in the total effective technique (p = 0.01), comparing the national competition with the international competition. Conclusion: Technical effectiveness of Brazilian wrestlers was found to be below the indices presented in studies with competitors from countries considered to have high world performance. In international competition, it presents a negative impact compared to national events. Level of Evidence IV; Therapeutic Studies - Investigation of Treatment Results.

RESUMEN Introducción: El Wrestling es una modalidad de combate milenaria, individual y de rendimiento complejo, que integra elevada complejidad técnico-táctica, asociada a una interacción bioenergética y un alto patrón coordinativo. En Brasil, el número de competidores en diferentes niveles aumentó significativamente en los últimos años, evidenciando la necesidad en la búsqueda de respuestas que auxilien a los entrenadores en las diferentes situaciones del calendario competitivo. La prescripción de los medios y métodos de entrenamiento en la lucha greco-romana tiene como objetivo el desarrollo de la efectividad técnica. Entre tanto, no hay evidencias de indicadores de efectividad técnica, en atletas de alto rendimiento brasileño en la lucha greco-romana, en competencias nacionales e internacionales. Objetivos: El objetivo de este estudio fue verificar y comparar la efectividad técnica de los atletas de lucha greco-romana de la selección brasileña, en dos competencias: una a nivel nacional y otra internacional. Métodos: Participaron de la investigación siete atletas de la selección brasileña de lucha greco-romana (edad: 25±5 años; estatura: 175±12 cm; masa corporal: 80± 21kg). Fueron realizados análisis de la técnica efectiva, no efectiva y total. Después de identificar la normalidad de los datos (SHAPIRO WILKS), fue utilizado el test de t de Student para la comparación de las variables, según el momento evaluado, considerando el nivel de significación de 5%. Resultados: Los resultados mostraron una disminución significativa (p = 0,03) en la técnica efectiva en pie y en la técnica efectiva total (p = 0,01), comparándose la competencia nacional con la internacional. Conclusión: Se concluyó que la eficacia técnica de los luchadores brasileños está por debajo de los índices presentados en estudios con competidores de países considerados de alto rendimiento mundial. En la competición internacional, presenta un impacto negativo en comparación con los eventos nacionales. Nivel de Evidencia IV; Estudios Terapéuticos - Investigación de Los Resultados Del Tratamiento.

RESUMO Introdução: O Wrestling é uma modalidade de combate milenar, individual e de rendimento complexo, que integra elevada complexidade técnico-táctica, associada a uma interação bioenergética e um alto padrão coordenativo. No Brasil, o número de competidores em diferentes níveis aumentou significativamente nos últimos anos, evidenciando a necessidade da busca de respostas que auxiliem os treinadores nas diferentes situações do calendário competitivo. A prescrição dos meios e métodos de treinamento na luta greco-romana visa o desenvolvimento da efetividade técnica. Entretanto, não há evidências de indicadores de efetividade técnica, em atletas de elite brasileira de luta greco-romana, em competições nacionais e internacionais. Objetivo: o objetivo do estudo foi verificar e comparar a efetividade técnica dos lutadores de luta greco-romana da seleção brasileira, em duas competições: uma no nível nacional e a outra internacional. Métodos: Participaram da investigação sete atletas da seleção brasileira de luta greco-romana (idade: 25±5 anos; estatura: 175±12 cm; massa corporal: 80± 21kg). Foram realizadas análises da técnica efetiva, não efetiva e total. Após identificar a normalidade dos dados (SHAPIRO WILKS), foi utilizado o teste t de Student para a comparação das variáveis, segundo o momento avaliado, considerando nível de significância de 5%. Resultados: Os resultados mostraram uma diminuição significativa (p = 0,03) na técnica efetiva em pé e na técnica efetiva total (p = 0,01), comparando-se a competição nacional com a internacional. Conclusão: Concluiu-se que a efetividade técnica dos lutadores brasileiros está abaixo dos índices apresentados em estudos com competidores de países considerados de alto desempenho mundial. Em competição internacional, apresenta um impacto negativo comparativamente a eventos nacionais. Nível de Evidência IV; Estudos Terapêuticos - Investigação dos Resultados do Tratamento.

Waiting for the next winter. Outpatient pediatric visits for respiratory infections before, during, and after the COVID-19 pandemic in the city of Buenos Aires.

INTRODUCTION: During the COVID-19 pandemic, pediatric visits due to acute lower respiratory infections (ALRIs) decreased, but most reports are from hospitalized patients. There is little information on this phenomenon in outpatients, who are the majority in ALRI. We evaluated the impact of the COVID-19 pandemic on ALRI-related outpatient visits in the City of Buenos Aires. METHODS: Observational study including all outpatient visits of children under 2 years of age to the public health system of the City of Buenos Aires, between 1 January 2018 and 31 December 2022. We analyzed the total number of visits and the ALRI-related visits, and their distribution throughout the study period. RESULTS: A total of 704,426 visits were registered, 7.38% of them due to ALRI. ALRI-related visits decreased from the implementation of a national lockdown (2020) and increased again as the restriction measures decreased, particularly the return to full school attendance (2021). In general, the proportion of ALRI-related visits was significantly higher in the cold months than in the warm ones (9.8% vs. 5.5%; odds ratio: 1.76, 95% confidence interval: 1.73-1.79; p < .001). This difference was observed before (2018 and 2019) and after the pandemic (2022), but not in 2020-2021. The peak of ALRI-related visits occurred in the cold months in pre-pandemic years (2018-2019), did not appear in 2020, reappeared delayed in 2021, and recovered seasonality in 2022. CONCLUSION: Outpatient ALRI-related visits decreased significantly in the city of Buenos Aires during the COVID-19 pandemic and currently seem to have recovered their magnitude and seasonality.

Prepublicaciones: Estudio descriptivo / Preprints: Descriptive study

Los "preprint" o pre-publicaciones (PP) son el manuscrito final y completo de una investigación, disponible en formato abierto y que aún no fue revisada por pares. Esta modalidad acelera el tiempo de presentación de resultados, permite enriquecer la versión final con contribuciones de lectores, pero no son aún investigaciones respaldadas por revisión de pares. Aunque ya conocidos, desde la pandemia COVID-19 los PP han cobrado cada vez más importancia en investigación clínica. Desde 2020, PubMed Central (PMC), y por lo tanto PubMed, incluye PP sobre investigaciones financiadas por los National Institutes of Health (NIH) y que figuren en repositorios seleccionados. Conocer la proporción de PP que alcanzan la publicación luego de la revisión por pares podría dar una idea de la validez de este formato. (AU)

Lignocellulosic Biomass for the Fabrication of Triboelectric Nano-Generators (TENGs)-A Review.

Growth in population and increased environmental awareness demand the emergence of new energy sources with low environmental impact. Lignocellulosic biomass is mainly composed of cellulose, lignin, and hemicellulose. These materials have been used in the energy industry for the production of biofuels as an eco-friendly alternative to fossil fuels. However, their use in the fabrication of small electronic devices is still under development. Lignocellulose-based triboelectric nanogenerators (LC-TENGs) have emerged as an eco-friendly alternative to conventional batteries, which are mainly composed of harmful and non-degradable materials. These LC-TENGs use lignocellulose-based components, which serve as electrodes or triboelectric active materials. These materials can be derived from bulk materials such as wood, seeds, or leaves, or they can be derived from waste materials from the timber industry, agriculture, or recycled urban materials. LC-TENG devices represent an eco-friendly, low-cost, and effective mechanism for harvesting environmental mechanical energy to generate electricity, enabling the development of self-powered devices and sensors. In this study, a comprehensive review of lignocellulosic-based materials was conducted to highlight their use as both electrodes and triboelectric active surfaces in the development of novel eco-friendly triboelectric nano-generators (LC-TENGs). The composition of lignocellulose and the classification and applications of LC-TENGs are discussed.

Use of an on/off tetracycline riboswitch to control protein production in Komagataella phaffii.

The methylotrophic yeast Komagataella phaffii is one of the most important microbial platforms to produce recombinant proteins. Despite its importance in the context of industrial biotechnology, the use of synthetic biology approaches in K. phaffii is hampered by the fact that few genetic tools are available for precise control of gene expression in this system. In this work, we used an RNA aptamer activated by tetracycline to modulate protein production at the translational level. Using lacZ as gene reporter, we have demonstrated significant reduction of the heterologous protein upon addition of tetracycline. Furthermore, this genetic control device was applied for the control of Ku70p. This protein is involved in non-homologous recombination and the control of its production paves the way for the development of strains exhibiting higher rates of homologous recombination.

[Circulation dynamics of respiratory syncytial virus and its relationship with ambient temperature. 25-year series in Buenos Aires] / Dinámica de circulación de virus sincicial respiratorio y su relación con la temperatura ambiental. Serie de 25 años en Buenos Aires.

Objective: To evaluate changes in RSV seasonality in the last 25 years and their correlation with the mean annual temperature. Methods: Cross-sectional study, based on RSV and temperature data from the City of Buenos Aires (1995-2019). For each year, we describe the beginning, end, and duration of the RSV season and the correlation with the mean annual temperature. Results: We identified 10,183 RSV infections. The duration of the RSV season decreased significantly (1995: 29 weeks vs. 2019: 18 weeks; R: 0.6 (p< 0.001)), due to an earlier ending (1995: week 45 vs. 2019: week 34; 0.6 (p<0.001)). No correlation was observed between mean annual temperature and the duration, start, or end of the RSV season. Conclusion: In the last 25 years, the duration of the RSV season has been significantly shortened due to an earlier ending, without correlation with temperature.

Introducción: El cambio climático global podría alterar la circulación del virus sincicial respiratorio (VSR). Objetivo: Evaluar modificaciones en la circulación de VSR en los últimos 25 años y su correlación con la temperatura ambiente. Métodos: Estudio transversal, utilizando registros de VSR y temperatura de la Ciudad de Buenos Aires (1995-2019). Para cada año, describimos inicio, fin y duración de la temporada de VSR y evaluamos su correlación con la temperatura media anual. Resultados: Se identificaron 10183 infecciones por VSR. La duración de la temporada disminuyó significativamente (1995: 29 semanas vs. 2019: 18 semanas; R: 0.6 (p< 0,001)), debido a una finalización más precoz (1995: semana 45 vs. 2019: semana 34; 0,6 (p<0,001)). No se observó correlación entre temperatura media anual y duración, comienzo ni finalización de la temporada de VSR. Conclusión: En los últimos 25 años, la duración de la temporada de VSR se acortó significativamente, sin correlación con la temperatura.

Reversing the biofilm-inducing effect of two xanthones from Garcinia mangostana by 3-methyl-2(5H)-furanone and N-butyryl-D-L homoserine lactone.

BACKGROUND: According to the WHO, 12 bacteria cause numerous human infections, including Enterobacteriaceae Klebsiella pneumoniae, and thus represent a public health problem. Microbial resistance is associated with biofilm formation; therefore, it is critical to know the biofilm-inducing potential of various compounds of everyday life. Likewise, the reversibility of biofilms and the modulation of persister cells are important for controlling microbial pathogens. In this work, we investigated the biofilm-inducing effects of xanthones from Garcinia mangostana on Klebsiella pneumoniae. Furthermore, we investigated the reversal effect of 3-methyl-2(5H)-furanone and the formation of persister cells induced by xanthones and their role in modulating the biofilm to the antibiotic gentamicin. METHODS: To analyze the biofilm-inducing role of xanthones from Garcinia mangostana, cultures of K. pneumoniae containing duodenal probe pieces were treated with 0.1-0.001 µM α- and γ-mangostin, and the biofilm levels were measured using spectrophotometry. To determine biofilm reversion, cultures treated with xanthones, or gentamicin were mixed with 3-methyl-2(5H)-furanone or N-butyryl-DL-homoserine lactone. The presence of K. pneumoniae persister cells was determined by applying the compounds to the mature biofilm, and the number of colony-forming units was counted. RESULTS: The xanthones α- and γ-mangostin increased K. pneumoniae biofilm production by 40% with duodenal probes. However, 3-methyl-2(5H)-furanone at 0.001 µΜ reversed biofilm formation by up to 60%. Moreover, adding the same to a culture treated with gentamicin reduced the biofilm by 80.5%. This effect was highlighted when 3-methyl-2(5H)-furanone was administered 6 h later than xanthones. At high concentrations of α-mangostin, persister K. pneumoniae cells in the biofilm were about 5 - 10 times more abundant than cells, whereas, with γ-mangostin, they were about 100 times more. CONCLUSION: Two xanthones, α- and γ-mangostin from G. mangostana, induced biofilm formation in K. pneumoniae and promoted persister cells. However, the biofilm formation was reversed by adding 3-methyl-2(5H)-furanone, and even this effect was achieved with gentamicin. In addition, this compound controlled the persister K. pneumoniae cells promoted by α-mangostin. Thus, synthetic, and natural biofilm-inducing compounds could harm human health. Therefore, avoiding these substances and looking for biofilm inhibitors would be a strategy to overcome microbial resistance and recover antibiotics that are no longer used.

Evaluación de residentes de pediatría con una modalidad virtual durante la pandemia COVID 19: presentación de una experiencia / Using a virtual mode for the pediatric residents evaluation during the COVID 19 pandemic: report of an experience

El examen clínico objetivo estructurado (ECOE) es una herramienta válida para medir competencias clínicas. En el contexto de la pandemia por COVID-19 se debieron adaptar las evaluaciones, habitualmente presenciales, a un formato virtual. El objetivo de este artículo es comunicar la experiencia de utilizar una modalidad virtual del ECOE para residentes de primer año de pediatría durante la pandemia por COVID-19. El ECOE comprendió 12 estaciones utilizando casos simulados en línea y consultas virtuales a distancia. Participaron del ECOE 115 residentes, aprobaron 110 (95,7%) y solo 17 participantes aprobaron el 100% de las estaciones. Las estaciones con mejor rendimiento fueron las referidas a alimentación complementaria, abordaje del traumatismo encéfalo craneano, interpretación de resultados de laboratorio y de imágenes radiológicas. El menor rendimiento se observó en uso de equipo de protección personal y vacunas. La encuesta de satisfacción fue respondida por 80/115 participantes (69,5%). El 91% de los participantes encontró fácil de utilizar la plataforma virtual. La mayoría (73/80) consideró que los temas fueron acordes al nivel de formación. La estación de pautas madurativas fue identificada como la más difícil. El 57% refirió que el ECOE les resultó útil para identificar puntos débiles en su formación. La implementación de una modalidad virtual del ECOE fue posible y presentó buena aceptación de los participantes.

The objective structured clinical examination (OSCE) is a helpful tool for assessing clinical competencies. During the COVID-19 pandemic, assessments usually carried out in person had to be adapted to a virtual format. We aim to report our experience using a virtual OSCE administered to first-year pediatric residents during the COVID-19 pandemic. The OSCE included 12 stations, including online simulated cases and virtual remote consultations. In total 115 residents participated in the OSCE; 110 (95.7%) passed the test, but only 17 participants passed all stations. The stations with the highest performance were related to complementary feeding, management of traumatic head injury, interpretation of lab test results and imaging. The lowest performance was observed using personal protective equipment and checking vaccine schedules. The user satisfaction survey was completed by 80 out of 115 participants (69.5%); 91 % of the participants found the virtual platform easy to use. Most of the residents (73/80) considered the topics to be appropriate for their training level. The station related to child development guidelines was identified as the most challenging. 57% reported that the OSCE was helpful for identifying weaknesses in their training. Conclusion: the implementation of a virtual OSCE was feasible and it was well accepted by the participants.

Impacto de la contaminación ambiental en las consultas por enfermedad respiratoria en niños menores de 2 años.

Introducción: La contaminación del aire incrementaría el riesgo de infección respiratoria aguda (IRA) en pediatría. Objetivo: evaluar el impacto de la contaminación del aire en las consultas por IRA realizadas en efectores del Gobierno de la Ciudad de Buenos Aires. Método: estudio ecológico, de series temporales. Fuentes de información: Agencia de Protección Ambiental, Servicio Meteorológico Nacional e Historia de Salud Integral del Sistema de Gestión Hospitalaria. Población: Pacientes menores de 2 años que consultaron por IRA a un efector del GCBA y que residían en una comuna con monitoreo ambiental continuo, durante el 2018. Variables de predicción: Niveles diarios de CO, NO2, PM10 de las estaciones de monitoreo ambiental continuo de la Ciudad Autónoma de Buenos Aires. Variables de resultado: número de consultas totales y por IRA. Variables a controlar: efector, sexo y temperatura media. Se construyó una definición operativa para seleccionar en la base de datos a las consultas objeto de estudio. Resultados: Se registraron 80.287 consultas, 24.847 por IRA (30%). Las consultas por IRA tuvieron correlación positiva en la estación "Córdoba" con el N2O (RR: 1,13 [1,00-1,28]). El número de consultas por IRA en los meses fríos fue mayor que en los cálidos (19,9% vs 11,9%; RR:1,67 [1,61-1,72]). Conclusión: Los valores promedios de PM10 y N2O muestran correlación con el número de las consultas totales y por infección respiratoria aguda, respectivamente. Las consultas se incrementaron durante el invierno.

Carbon Quantum Dots Based on Marine Polysaccharides: Types, Synthesis, and Applications.

The marine environment offers a vast array of resources, including plants, animals, and microorganisms, that can be utilized to extract polysaccharides such as alginate, carrageenan, chitin, chitosan, agarose, ulvan, porphyra, and many more. These polysaccharides found in marine environments can serve as carbon-rich precursors for synthesizing carbon quantum dots (CQDs). Marine polysaccharides have a distinct advantage over other CQD precursors because they contain multiple heteroatoms, including nitrogen (N), sulfur (S), and oxygen (O). The surface of CQDs can be naturally doped, reducing the need for excessive use of chemical reagents and promoting green methods. The present review highlights the processing methods used to synthesize CQDs from marine polysaccharide precursors. These can be classified according to their biological origin as being derived from algae, crustaceans, or fish. CQDs can be synthesized to exhibit exceptional optical properties, including high fluorescence emission, absorbance, quenching, and quantum yield. CQDs' structural, morphological, and optical properties can be adjusted by utilizing multi-heteroatom precursors. Moreover, owing to their biocompatibility and low toxicity, CQDs obtained from marine polysaccharides have potential applications in various fields, including biomedicine (e.g., drug delivery, bioimaging, and biosensing), photocatalysis, water quality monitoring, and the food industry. Using marine polysaccharides to produce carbon quantum dots (CQDs) enables the transformation of renewable sources into a cutting-edge technological product. This review can provide fundamental insights for the development of novel nanomaterials derived from natural marine sources.

Ética en investigación: desafíos durante la pandemia / Research ethics: challenges during the pandemic

Durante la pandemia de Covid-19 los hospitales pediatricos se vieron menos afectados, debido a la menor infección en niños, y sus recursos fueron reasignados en distintas tareas.. El Comité de Ética en Investigación del Hospital General de Niños Pedro de Elizalde presenta los distintos procedimientos implementados en esta emergencia, para sostener diferentes investigaciones, y que les permitió una rápida respuesta a esta situación.

Acute respiratory health effects of air pollution on consultations in children under 2 years old / [Impacto de la contaminación ambiental en las consultas por enfermedad respiratoria en niños menores de 2 años.]

Introduction: Air pollution would increase the risk of severe infection repiratory in pediatrics. Research Sources: Environmental Protection Agency, National Meteorological. Service and Integral Health History of the Hospital Management System. Population: Patients under 2 years old who consulted for severe infection repiratory in effectors of Buenos Aires City Government and lived commune with continuous environmental monitoring during 2018. Predictors were daily levels of air pollutants (carbon monoxide, nitrous dioxide, particulate matter < 10 µ). Pollutants were measured at three monitoring stations. Temporal variables (media temperature), sex and effector were controlled. Result Variable: Total numbers of visits and total numbers of visits for severe infection respiratory. To select in the data base the visits to analyze an operative definition was made. Objective: Review impact of air pollution visits for severe infection repiratory in effectors of Buenos Aires City Government. Method: Ecologic research, time-series. Results: 80.287 visits were registered, 24.847 for severe infection respiratory (30%). The visits for severe infection respiratory had positive correlation in Cordoba station with N2O (RR: 1,13 [1,00-1,28]). The numbers of visits for severe infection respiratory was higher during cold months than warm months. (19,9% vs 11,9%; RR:1,67 [1,61-1,72]). Conclusion: average values of PM10 and N2O show correlation with the numbers of total visits and visits for severe infection respiratory. The visits increase during winter.

Introducción: La contaminación del aire incrementaría el riesgo de infección respiratoria aguda (IRA) en pediatría. Objetivo: evaluar el impacto de la contaminación del aire en las consultas por IRA realizadas en efectores del Gobierno de la Ciudad de Buenos Aires. Método: Estudio ecológico, de series temporales. Fuentes de información: Agencia de Protección Ambiental, Servicio Meteorológico Nacional e Historia de Salud Integral del Sistema de Gestión Hospitalaria. Población: Pacientes menores de 2 años que consultaron por IRA a un efector del GCBA y que residían en una comuna con monitoreo ambiental continuo, durante el 2018. Variables de predicción: Niveles diarios de CO, NO2, PM10 de las estaciones de monitoreo ambiental continuo de la Ciudad Autónoma de Buenos Aires. Variables de resultado: número de consultas totales y por IRA. Variables a controlar: efector, sexo y temperatura media. Se construyó una definición operativa para seleccionar en la base de datos a las consultas objeto de estudio. Resultados: Se registraron 80.287 consultas, 24.847 por IRA (30%). Las consultas por IRA tuvieron correlación positiva en la estación "Córdoba" con el N2O (RR: 1,13 [1,00-1,28]). El número de consultas por IRA en los meses fríos fue mayor que en los cálidos (19,9% vs 11,9%; RR:1,67 [1,61-1,72]). Conclusión: Los valores promedios de PM10 y N2O muestran correlación con el número de las consultas totales y por infección respiratoria aguda, respectivamente. Las consultas se incrementaron durante el invierno.