Extraction of geraniol from palmarosa oil using hydrotropic solvents / Extracción de geraniol del aceite de palmarosa utilizando solventes hidrotrópicos

The extraction of geraniol from palmarosa oil using hydrotropic solvents was investigated. Palmarosa oil possesses an appealing rose aroma and properties like anti - inflammatory, antifungal, and antioxidant due to the presence of geraniol. The extraction of geraniol from palmarosa oil by using distillation methods like steam dis tillation and fractional distillation was a laborious process. So hydrotropes were tried for extraction. The geraniol yield and purity depend on parameters like concentration of hydrotrope, solvent volume ratio, and time period. Using the Box Benkhem Desig n (BBD), the extraction process was optimized. One of the major advantages of using hydrotropic solvents is that they were classified as green solvents, and recovery of solvents is also possible. To reduce the extraction time probe sonication is carried ou t. Different hydrotropic solvents with probe sonication are done on palmarosa oil by altering various process parameters to study the separation, yield, and purity.

Se investigó la extracción de geraniol del aceite de palmarosa utilizando solventes hidrotrópicos. El aceite de palmarosa posee un atractivo aroma a rosa y propiedades antiinflamatorias, antifúngicas y antioxidantes debido a la pr esencia de geraniol. La extracción de geraniol del aceite de palmarosa mediante métodos de destilación como la destilación por vapor y la destilación fraccionada ha sido un proceso laborioso. Por lo tanto, se probaron los hidrotropos para la extracción. El rendimiento y la pureza del geraniol dependen de parámetros como la concentración del hidrotropo, la relación de volumen del solvente y el período de tiempo. Se optimizó el proceso de extracción usando el diseño Box Benkhem (BBD). Una de las principales v entajas de usar solventes hidrotrópicos es que se clasifican como solventes verdes y también es posible recuperar los solventes. Para reducir el tiempo de extracción, se lleva a cabo una sonda de ultrasonido. Se realizan diferentes solventes hidrotropos co n sonda de ultrasonido en el aceite de palmarosa alterando varios parámetros del proceso para estudiar la separación, el rendimiento y la pureza.

Efeitos dos líquidos ativados com plasma atmosférico sobre Candida albicans / Application of plasma activated liquids on Candida albicans

O incremento no número de casos refratários aos tratamentos convencionais e a limitação de opções terapêuticas são alguns dos desafios encontrados no tratamento da candidose bucal, apontando para a necessidade de terapias alternativas. A utilização da tecnologia de plasma de forma indireta, pela exposição prévia de líquidos ex situ, tem mostrado resultados promissores, trazendo inúmeras vantagens para a aplicação clínica. Até o momento, pouco se conhece sobre a atividade antifúngica do líquido ativado com plasma (LAP) e não foram detectados relatos sobre sua aplicabilidade no tratamento da candidose bucal. Com base neste cenário, o objetivo deste projeto foi avaliar a atividade do líquido ativado com plasma sobre Candida albicans, principal agente etiológico da candidose bucal. Para tanto, foram determinadas as condições de obtenção do LAP com maior efeito antifúngico frente a C. albicans. O LAP foi gerado em um reator de plasma tipo arco deslizante (gliding arc). Os gases empregados incluíram argônio, ar comprimido seco e suas misturas em diversas concentrações, ajustando-se o fluxo de gás e a potência conforme necessário. Avaliou-se a eficácia antifúngica de diferentes líquidos ativados contra C. albicans, tanto em estado planctônico quanto em biofilmes, visando identificar o mais efetivo. As espécies reativas dos LAP foram caracterizadas utilizando técnicas espectrofotométricas, juntamente com a avaliação dos parâmetros físico-químicos. Os resultados dos ensaios foram submetidos a análise estatística, estabelecendo-se um nível de significância de 5% para a interpretação dos dados. Observou-se que a solução salina 0,9% ativada com plasma de argônio (S1), água destilada ativada com plasma de argônio (D1) e água destilada ativado com a mistura dos gases argônio e ar comprimido (S2) apresentaram a maior atividade antifúngica sobre células planctônicas de C. albicans quando expostas por 30 minutos ao LAP. O grupo D1 apresentou maior ação frente aos biofilmes de 24 e 48 horas e o S1 frente a biofilmes de 48 horas apenas quando exposto por 30 minutos ao LAP. Ambos os LAPs apresentaram ação antifúngica após terem sido congelados e armazenados por 1 dia após a ativação. Os grupos D1 e S1 não apresentaram perfil citotóxico nos ensaios realizados. Pode-se concluir que os LAPs apresentaram ação inibitória sobre células planctônicas e sobre biofilmes de C. albicans, sem citotoxicidade para células de mamíferos, sugerindo seu potencial como adjuvante às terapias para o controle da candidose.(AU)

The increase in the number of cases refractory to conventional treatments and the limitation of therapeutic options is due to some two challenges encountered in the treatment of oral candidiasis, pointing to the need for alternative therapies. The use of plasma technology indirectly, for the exposition of liquids ex situ, has shown promising results, providing numerous advantages for clinical application. Currently, little is known about the antifungal activity of plasma-activated liquid (LAP) and there are no reports on its applicability in oral candidiasis treatment. Based on this scenario, the objective of this project is to validate the application of plasma-activated liquid as an adjuvant in the treatment of oral candidiasis. Therefore, certain conditions for obtaining LAP have greater antifungal effect against Candida albicans. The LAP was generated in a gliding arc type plasma reactor. The gases used include argon, dry compressed and their mixtures in various concentrations, adjusting the gas flow and power as necessary. The antifungal efficacy of different liquids activated against C. albicans is evaluated, both in the planktonic state and in biofilms, aiming to identify the most effective. The relative species of LAP were characterized using spectrophotometric techniques, together with the evaluation of two physical-chemical parameters. The results of two tests were submitted to statistical analysis, establishing a significance level of 5% for the interpretation of the data. It was observed that the groups that presented the greatest antifungal activity in planktonic cells of C. albicans were the groups of 0.9% saline solution activated with argonium plasma (S1), or of distilled water activated with argonium plasma (D1). e or distilled water activated with a mixture of two argon gases and compressed air (S2). The D1 group presented against biofilms of 24 and 48 hours and the S1 against biofilms of only 48 hours. Both LAPs are presented with antifungal coating and have been frozen and stored for 1 day after activation. The groups D1 and S1 do not present a cytotoxic profile in the tests carried out. It can be concluded that the LAPs have antifungal activity on planktonic cells and on biofilms and do not present a toxicity profile for human cells, being potent adjuvants in therapies for or controlling infections caused by C. albicans (AU)

Influence of the dilution method on the intraocular duration of C3F8 in vitrectomy for macular hole: a randomized clinical trial

ABSTRACT Purpose: To compare the injection of small amounts of undiluted C3F8 with the traditional gas injection in vitrectomy for macular hole treatment. Methods: This clinical trial included 26 individuals divided into two groups. Group 1 received an intravitreal injection of 0.9-1.0 mL of 100% C3F8, and Group 2 received 15-20 mL of 20% C3F8. Results: The median intraocular gas duration was 31 days in Group 1 and 34 in Group 2. The median letter gains in corrected distance visual acuity for the 26th postoperative week were 20 letters in Group 1 and 12.5 in Group 2. The median intraocular pressure was normal in both groups. Primary anatomical success was 11/13 in both groups. Conclusions: The use of C3F8 gas in a small undiluted volume is an alternative that slightly reduces the duration of the gas without negatively affecting the anatomical and visual response.

Estimación de emisiones de gases de efecto invernadero en la dieta de mujeres adolescentes en áreas rurales de oriente de Guatemala / Estimation of greenhouse of gas emissions in the diet of adolescent women in rural areas of eastern Guatemala

Introducción. La producción de alimentos es una de las principales causas de Emisiones de Gases de Efecto Invernadero (GEI). Estimar las emisiones GEI de la dieta es el punto de partida para definir dietas saludables y sostenibles con el ambiente. Objetivo. Estimar el total GEI de la dieta de mujeres adolescentes del oriente de Guatemala, así como la contribución de grupos de alimentos a este valor. Materiales y métodos. En el contexto de un estudio de agricultura y nutrición en el oriente de Guatemala, se realizó un análisis secundario de los datos dietéticos (Recordatorio de 24 horas) de 2082 mujeres adolescentes. Los alimentos reportados fueron enlazados con la base de datos SHARP, que contiene estimaciones de GEI para 944 alimentos. La variable de enlace fue un código único armonizado con el sistema de clasificación FoodEx2. Resultados. La dieta es poco diversa, principalmente a base de grupos de alimentos de origen vegetal, con poca presencia de alimentos de origen animal. El GEI de la dieta fue de 2,3 Kg CO2 eq/ per cápita/día, con la mayor contribución de comidas preparadas (26,7%) y panes, tortillas y similares (12,8%). Conclusiones. La dieta de las mujeres adolescentes de áreas rurales de Guatemala tiene un GEI inferior al reportado en otros países de la región para estratos socioeconómicos con mayor consumo de alimentos de origen animal. Este estudio es el punto de partida para sistematizar la metodología para continuar con las estimaciones de GEI en Guatemala(AU)

Introduction. Food production is one of the main causes of Greenhouse Gas Emissions (GHGE). Estimating GHG emissions from the diet is the starting point for defining healthy and environmentally sustainable diets. Objective. Estimate the total GHGE in the diet of adolescent women from eastern Guatemala, as well as the contribution of food groups to this value. Materials and methods. In the context of an agriculture and nutrition study in eastern Guatemala, a secondary analysis of dietary data (24-hour recall) of 2082 adolescent women was performed. The reported foods were linked to the SHARP database, which contains GHGE estimates for 944 foods. The linking variable was a unique code harmonized with the FoodEx2 classification system. Results. The diet is not diverse, mainly based on food groups of plant origin, with little presence of foods of animal origin. The GHG of the diet was 2.3 Kg CO2 eq/per capita/day, with the greatest contribution from prepared foods (26.7%) and breads, tortillas and similar products (12.8%). Conclusions. The diet of adolescent women in rural areas of Guatemala has a lower GHG than that reported in other countries in the region for socioeconomic strata with greater consumption of foods of animal origin. This study is the starting point to systematize the methodology to continue with GHG estimates in Guatemala(AU)

Calidad nutricional e impacto en medio ambiente por los insumos de un comedor universitario en Uruguay / Nutritional quality and environmental impact by the inputs of a university canteen in Uruguay

El espacio de comedores son una forma de garantizar el acceso a alimentos seguros, saludables y medio ambientalmente responsables para los estudiantes universitarios. Objetivo. Este estudio tuvo como objetivo caracterizar los estándares del menú, a partir de la evaluación de la calidad nutricional y del impacto en el medio ambiente por los insumos utilizados para su elaboración por un Comedor Universitario (CU) en Uruguay. Materiales y métodos. Se trató de un estudio de caso retrospectivo, relativo al año 2021. Las variables evaluadas fueron a) cantidad total de alimento comprado en kilogramos (kg); b) cantidad en kilocalorías (kcal) e impactos ambientales por: c) generación de residuos; d) huella hídrica (HH); y e) gases de efecto invernadero (GEI). También se realizaron cálculos para evaluar la ecoeficiencia (EE). Resultados. El CU sirvió 33.740 comidas en 2021, de las cuales el 87,1% fueron almuerzos. De los 78 tipos de alimentos comprados, 41 de ellos representaron el 93,17% del total en kilogramos. En la calidad nutricional, menos del 10% se clasificaron como alimentos procesados o ultraprocesados. En la evaluación de aspectos nutricionales e impactos ambientales, los alimentos de origen animal representaron el 26,52% del total en kg y el 69,78% de los HH. Un alimento de origen vegetal tuvo el mayor impacto de GEI debido a su origen. En cuanto a la EE, la valoración general mostró un resultado de 0,0626 para los alimentos de origen animal y 0,3838 para los de origen vegetal. Conclusiones. Corresponde a los servicios de alimentación para colectividades considerar, en la planificación del menú, además de la calidad nutricional y sanitaria de la oferta alimentaria, los impactos ambientales que estas genera(AU)

The canteens are a way to guarantee access to safe, healthy and environmentally responsible food for university students. Objective. The purpose of this research was to characterize the menu standards, based on the evaluation of the nutritional quality and the environmental impact of the inputs used for its preparation by a university canteen in Uruguay. Materials and methods. This was a retrospective case study, relating to the year 2021. The variables evaluated were a) total amount of food purchased in kilograms (kg); b) quantity in kilocalories (kcal) and environmental impacts due to: c) waste generation; d) water footprint (WF); and e) greenhouse gases (GHG). Calculations were also performed to assess eco-efficiency (EE). Results. The university canteen served 33,740 meals in 2021, of which 87.1% were lunches. Of the 78 types of food purchased, 41 of them represented 93.17% of the total in kilograms. In nutritional quality, less than 10% are classified as processed or ultra-processed foods. In the evaluation of nutritional aspects and environmental impacts, foods of animal origin represented 26.52% of the total in kg and 69.78% of WF. A vegetal based food had the highest GHG impact due to its origin. Regarding the EE calculations, the general assessment showed a result of 0.626 for foods of animal origin and 0.3838 for those of vegetable origin. Conclusions. It corresponds to the food services for communities to consider, in the planning of the menu, in addition to the nutritional and sanitary quality of the food offer, the environmental impacts that it generates(AU)

Juicios de daños y aporte de los tribunales chilenos ante los desafíos ético-ambientales que impone el cambio climático / Litigation for damages and contribution of the Chilean courts to the ethical-environmental challenges posed by climate change / Julgamento de danos e contribuições dos tribunais chilenos diante dos desafios ético-ambientais trazidos pela mudança climática

Este artículo muestra que la experiencia acumulada por la Corte Suprema chilena en juicios sobre responsabilidad civil y ambiental, debiera permitirle abordar los problemas ético-ambientales y jurídicos que el calentamiento global implica, sea previniendo daños mediante la imposición a los principales emisores de gases de efecto invernadero, incluido el Estado, del deber de reducir acelerada y significativamente las emisiones, sea exigiendo y haciendo cumplir la obligación de adaptación al cambio climático mediante la atribución de responsabilidad extracontractual o ambiental.

This article shows that the experience accrued by the Chilean Supreme Court in lawsuits on tort and environmental liability, should allow it to address the ethical-environmental and legal issues that global warming implies, either by preventing harm through the imposition on the major emitters of greenhouse gases, including the State, of the duty to reduce emissions rapidly and significantly, or by demanding and enforcing the obligation to adapt to climate change through the attribution of tort liability or environmental liability.

Esse artigo mostra que a experiência acumulada pela Corte Suprema chilena em julgamentos sobre responsabilidade civil e ambiental, deveria permitir-lhe abordar os problemas ético-ambientais e jurídicos que o aquecimento global implica, seja prevenindo danos mediante a imposição aos principais emissores de gases de efeito estufa, incluindo o Estado, do dever de reduzir acelerada e significativamente as emissões, seja exigindo e fazendo cumprir a obrigação de adaptação à mudança climática mediante a atribuição de responsabilidade extracontratual ou ambiental.

Las nanoestructuras de ZnO y sus aplicaciones como sensor de gas H2S / The ZnO nanostructures and their applications as a H2S gas sensor

RESUMEN Existe un interés global en la detección de gases tóxicos, para la protección del medio ambiente y los seres humanos. Se han desarrollado múltiples estudios enfocados en el uso de sensores de gases basados en óxidos metálicos, como es el óxido de zinc (ZnO), el cual presenta propiedades electrónicas específicas como sensor de gases por ser un semiconductor tipo n y bajo costo de producción. El objetivo de este trabajo fue analizar el uso de nanoestructuras de ZnO, para la fabricación de sensores del gas ácido sulfhídrico (H2S), así como las técnicas de obtención más comunes de dichas estructuras. Las características de las nanoestructuras de óxido de zinc (NE´s-ZnO) varían por efecto del método de obtención, generando diferentes morfologías y tamaño, que impactan en la capacidad de detección de gas (0.5 ppm a 600 ppm) y en el rango de temperatura que se requiere. Los avances en la generación de diversas NE´s-ZnO facilitarán la posibilidad de generar sensores que puedan ser utilizados en detectores portátiles y operen a temperatura ambiente, lo cual es un reto actual.

ABSTRACT There is a global interest in the detection of toxic gases for the protection of the environment and human beings, using low-cost and easy-to-use sensors. Multiple studies have focused on the use of gas detectors based on metal oxides, such as zinc oxide (ZnO), which has specific electronic properties as a gas detector because it is an n-type semiconductor and it has a low production cost. The objective of this work was to analyze the use of ZnO nanostructures for the manufacturing of hydrogen sulfide (H2S) gas sensors, as well as the most common techniques for obtaining these structures. The characteristics of zinc oxide nanostructures (NE´s-ZnO) vary due to the effect of the obtaining method, generating different morphologies and sizes, which impacts gas detection performance (0.5 ppm up to 600 ppm) and in the temperature range that is required. Advances in the design of various NE's-ZnO will have the possibility of generating sensors that can be used in portable detectors and operate at room temperature, which is a current challenge.

Double bubble pneumo-descemetopexy for the management of Descemet membrane detachment: An innovative technique

A 62-year-old woman was referred with poor vision following manual small incision cataract surgery. On presentation, the uncorrected distance visual acuity in the involved eye was 3/60, whereas slit-lamp examination revealed a central corneal edema with the peripheral cornea relatively clear. Direct focal examination with a narrow slit upper border and lower margin of detached rolled up Descemet’s membrane (DM) could be visualized. We performed a novel surgical approach, “double-bubble pneumo-descemetopexy.” The surgical procedure included unrolling of DM with “small air bubble” and descemetopexy with “big bubble.” No postoperative complications were observed, and best corrected distance visual acuity improved to 6/9 at 6 weeks. The patient had a clear cornea and maintained BCVA 6/9 during 18 months at follow-up. Double-bubble pneumo-descemetopexy, a more controlled technique, provides a satisfactory anatomical and visual outcome in DMD without the need for endothelial keratoplasty (Descemet’s stripping endothelial keratoplasty or DMEK) or penetrating keratoplasty.

Arterial Blood Gases in Normal Subjects at 2240 Meters Above Sea Level: Impact of Age, Gender, and Body Mass Index

ABSTRACT Background The values of arterial blood gases (ABG) change with altitude above sea level; empirical verification is essential because ventilatory acclimatization varies with ethnicity and a population's adaptation. Objective The aim of the study was to describe ABG in a healthy population residing at 2,240 meters above sea level, to identify the mean level of alveolar ventilation (PaCO2), and to know whether a progressive increase in PaCO2 occurs with age and the impact of increasing body mass index (BMI). Methods We conducted a cross-sectional study in a referral center for respiratory diseases in Mexico City. Associations among variables with correlation coefficient and regression models of PaO2, SaO2, and P(A-a)O2 as dependent variables as a function of age, BMI, minute ventilation, or breathing frequency were explored. Results Two hundred and seventeen healthy subjects were evaluated with a mean age of 40 ± 15 years, mean of the PaO2 was 71 ± 6 mmHg, SaO2 94% ± 1.6%, PaCO2 30.2 ± 3.4 mmHg, HCO3 20 ± 2 mmol/L, BE-2.9 ± 1.9 mmol/L, and the value of pH was 7.43 ± 0.02. In a linear regression, the main results were PaO2 = 77.5-0.16*age (p < 0.0001) and with aging P(A-a)O2 tended to increase 0.12 mmHg/year. PaCO2 in women increased with age by 0.075 mmHg/year (p = 0.0012, PaCO2 =26.3 + 0.075*age). SaO2 and PaO2 decreased significantly in women with higher BMI 0.14% and 0.52 mmHg per kg/m2, (p = 0.004 and 0.002 respectively). Conclusion Mean PaCO2 was 30.7 mmHg, implying a mean alveolar ventilation of around 30% above that at sea level.

Bioconversion of C1 gases and genetic engineering modification of gas-utilizing microorganisms / 生物工程学报

C1 gases including CO, CO2 and CH4, are mainly derived from terrestrial biological activities, industrial waste gas and gasification syngas. Particularly, CO2 and CH4 are two of the most important greenhouse gases contributing to climate change. Bioconversion of C1 gases is not only a promising solution to addressing the problem of waste gases emission, but also a novel route to produce fuels or chemicals. In the past few years, C1-gas-utilizing microorganisms have drawn much attention and a variety of gene-editing technologies have been applied to improve their product yields or to expand product portfolios. This article reviewed the biological characteristics, aerobic or anaerobic metabolic pathways as well as the metabolic products of methanotrophs, autotrophic acetogens, and carboxydotrophic bacteria. In addition, gene-editing technologies (e.g. gene interruption technology using homologous recombination, group Ⅱ intron ClosTron technology, CRISPR/Cas gene editing and phage recombinase-mediated efficient integration of large DNA fragments) and their application in these C1-gas-utilizing microorganisms were also summarized.

Gas tamponade followed by laser treatment for macular retinal detachment secondary to optic pit / Tamponamento com gás seguido de laser para descolamento de retina secundário à fosseta de disco óptico

ABSTRACT Purpose: The study aimed to describe anatomic and visual outcomes associated with perfluoropropane intravitreal injection followed by laser treatment for macular retinal detachment secondary to optic disc pit. Methods: A single-center, retrospective study. Medical records of all patients treated at a tertiary retina referral center were evaluated between 2011 and 2018 for congenital optic disc pit-associated macular detachment with 0.3 ml 100% perfluoropropane intravitreal injection followed by retinal laser photocoagulation along the temporal optic disc margin as the initial treatment. Results: Six patients with optic disc pit-associated macular detachment were identified, with postoperative follow-up ranging from 13 to 52 months (mean: 28 months). Spectral domain optical coherence tomography (SD-OCT) showed complete fluid resolution without recurrence in five of the six cases. Four cases showed complete reabsorption after Intravitreal perfluoropropane plus laser, one patient needed an extra procedure (pars plana vitrectomy with inner limiting membrane peeling and pedicle flap inversion over the temporal optic disc margin) to achieve complete fluid reabsorption, and one patient had persistent intraretinal fluid and denied additional surgeries. The time between the initial procedure and total fluid reabsorption varied from 6.5 to 41 months (mean: 19.5 months). Best-corrected visual acuity improved after surgery on the last follow-up visit in all cases. Conclusion: 100% perfluoropropane intravitreal injection followed by photocoagulation along temporal optic disc margin was associated with anatomic and visual improvement in most cases, representing an alternative treatment approach for optic disc pit-associated macular detachment.

RESUMO Objetivo: Descrever os resultados anatômicos e visuais associados à injeção intravítrea de perfluoropropano seguida de tratamento a laser para descolamento de retina macular secundário à fosseta do disco óptico. Métodos: Estudo retrospectivo em um único centro. Foram revisados os prontuários médicos dos pacientes com descolamento macular associado a fosseta do disco óptico congênito em um centro de referência terciário de retina entre 2011 e 2018. Todos receberam como estratégia de tratamento inicial injeção intravítrea de perfluoropropano 100% seguido por fotocoagulação a laser ao longo da margem temporal do disco óptico. Resultados: Foram identificados seis pacientes com descolamento macular associado a fosseta do disco óptico durante o período do estudo. O seguimento pós-operatório variou de 13 a 52 meses, com média de 28 meses. SD-OCT demonstrou resolução completa do fluido em cindo dos seis casos, sem recorrência. Quatro casos apresentaram reabsorção completa após perfluoropropano intravítreo associado a laser, e um paciente necessitou de procedimento adicional (vitrectomia via pars plana com peeling da membrana limitante interna e inversão do retalho do pedículo sobre a margem temporal do disco óptico) para obter reabsorção completa de fluidos. Um paciente apresentou fluido intrarretiniano persistente e negou tratamentos adicionais. O tempo entre o procedimento inicial e a resolução completa do fluido variou entre 6,5 a 41 meses, com média de 19,5 meses. A acuidade visual corrigida melhorou após a cirurgia, considerando a última consulta de acompanhamento em todos os casos. Conclusão: A injeção intravítrea de perfluoropropano 100% seguida de fotocoagulação ao longo da margem temporal da margem do disco óptico foi associada à melhora anatômica e visual na maioria dos casos e representa uma abordagem terapêutica alternativa para o descolamento macular associado a fosseta do disco óptico.

Delta de CO2 como estrategia del manejo integral del paciente con choque séptico en la UCI / CO2 delta as a strategy for the comprehensive management of patients with septic shock in the ICU / Delta CO2 como estratégia para o tratamento integral do paciente com choque séptico na UTI

Resumen: Introducción: el choque séptico es un subconjunto de sepsis en el que las anomalías circulatorias, celulares y metabólicas subyacentes son lo suficientemente profundas para aumentar de manera sustancial la mortalidad. Estos pacientes pueden ser identificados en un contexto clínico de choque séptico con hipotensión persistente. La importancia de vigilar valores de delta de pCO2 (presión parcial de dióxido de carbono) de 6 mmHg sirve como herramienta complementaria para evaluar el flujo sanguíneo adecuado hacia la demanda metabólica global. Objetivo: demostrar que el delta de pCO2 es útil en el manejo integral del paciente con choque séptico en la unidad de cuidados intensivos para dirigir el tratamiento de acuerdo con este biomarcador, que se registró al ingreso y a las 24 horas, se relacionaron al pronóstico y a la mortalidad en choque séptico. Material y métodos: estudio descriptivo, ambispectivo, longitudinal y analítico. El universo se compuso de los pacientes que ingresaron a la Unidad de Cuidados Intensivos del Hospital General «La Villa¼ y del Hospital General «Dr. Rubén Leñero¼. Diseño de la maniobra: se tomaron gasometrías arterial y venosa de los pacientes que ingresaron a la UCI, se calculó el delta de pCO2 para ver si los valores de este biomarcador estaban por arriba o debajo de 6 mmHg, ya que un delta de pCO2 se relaciona con mortalidad; sin embargo, el delta de pCO2 se comparó contra el lactato para correlacionar niveles mayores de lactato de 2 mmol/L con la mortalidad. y finalmente observar cuál de los dos biomarcadores es más útil. Se utilizó estadística descriptica para los resultados. Conclusión: de acuerdo a los resultados encontrados en este estudio, se puede decir que el delta de pCO2 y el lactato predijeron el fallecimiento de 15%, lo cual tiene una significancia positiva débil (p = 0.245).

Abstract: Introduction: septic shock is a subset of sepsis in which underlying circulatory, cellular, and metabolic abnormalities are profound enough to substantially increase mortality. These patients can be identified in a clinical setting of septic shock with persistent hypotension. The importance of monitoring delta pCO2 values of 6 mmHg serves as a complementary tool to assess adequate blood flow towards global metabolic demand. Objective: to demonstrate that the pCO2 delta is useful in the comprehensive management of patients with septic shock in the Intensive Care Unit to direct the treatment according to this biomarker (pCO2 delta) that was recorded at admission and at 24 hours, were related to prognosis and mortality in septic shock. Material and methods: descriptive, ambispective, longitudinal and analytical study. The universe was made up of patients admitted to the ICU of the La Villa and Rubén Leñero General Hospitals. Maneuver design: arterial and venous blood gases were taken from the patients admitted to the ICU, the pCO2 delta was calculated to see if the values of this biomarker were above or below 6 mmHg, since a pCO2 delta is related to with mortality; however, delta pCO2 was compared against Lactate to correlate lactate levels greater than two with mortality and finally see which of the two biomarkers is more useful. Descriptive statistics were used for the results. Conclusion: according to the results found in this study, it can be said that delta pCO2 and lactate predicted the death of 15%, which has a weak positive significance (p = 0.245).

Resumo: Introdução: choque séptico é um subconjunto de sepse em que anormalidades circulatórias, celulares e metabólicas subjacentes são profundas o suficiente para aumentar substancialmente a mortalidade, esses pacientes podem ser identificados em um cenário clínico de choque séptico com hipotensão persistente. A importância do monitoramento de valores Delta de pCO2 de 6 mmHg serve como ferramenta complementar para avaliar o fluxo sanguíneo adequado à demanda metabólica global. Objetivo: demonstrar que o Delta pCO2 é útil no manejo integral de pacientes com choque séptico na Unidade de Terapia Intensiva para direcionar o tratamento de acordo com este biomarcador (Delta pCO2) que foi registrado na admissão e em 24 horas, relacionado ao prognóstico e mortalidade no choque séptico. Material e métodos: estudo descritivo, ambispectivo, longitudinal e analítico. O universo foi constituído pelos pacientes internados na UTI dos Hospitais Gerais La Villa e Rubén Leñero. Desenho da estratégia: foram coletadas gasometrias arteriais e venosas dos pacientes internados na UTI, o Delta pCO2 foi calculado para ver se os valores desse biomarcador estavam acima ou abaixo de 6 mmHg, pois um Delta pCO2 está relacionado com mortalidade; entretanto, Delta pCO2 foi comparado com Lactato para correlacionar níveis de lactato maiores que 2 com mortalidade e finalmente observar qual dos dois biomarcadores é mais útil. Foram usadas estatísticas descritivas para os resultados. Conclusão: de acordo com os resultados encontrados neste estudo, pode-se dizer que Delta pCO2 e Lactato predizem óbito em 15%, o que tem uma fraca significância positiva (p = 0.245).

Índices de oxigenación como marcadores pronósticos en neumonía grave por SARS-CoV-2 / Oxygenation indices as prognostic marker in severe pneumonia due to SARS-CoV-2 / Índices de oxigenação como marcadores prognósticos na pneumonia grave por SARS-CoV-2

Resumen: Introducción: a través de los índices de oxigenación valoramos la función del sistema respiratorio de oxigenación y ventilación. Objetivo: determinar el valor de los índices de oxigenación como factor de pronóstico para el desenlace en neumonía grave por SARS-CoV-2. Material y métodos: estudio retrospectivo, longitudinal, descriptivo, analítico. Se incluyeron pacientes > 18 años con diagnóstico de neumonía por SARS-CoV-2 entre el 01 junio y el 31 de diciembre de 2020. Se clasificó a los pacientes de acuerdo al desenlace: sobreviviente o no sobreviviente. Se empleó estadística descriptiva y pruebas paramétricas y no paramétricas de acuerdo al caso, se construyeron curvas ROC (Receiver Operating Characteristic Curve) para determinar los puntos de corte de los gases arteriales con la mejor sensibilidad y especificidad y se determinó el área bajo la curva (ABC) para el desenlace fatal. Resultados: se incluyeron 175 pacientes, 70.3% correspondió al sexo masculino, la media de edad fue de 56 años (rango intercuartil 45-64). El grupo de sobrevivientes incluyó 51 pacientes y el grupo de no sobrevivientes 124 pacientes. Al analizar los gases arteriales al momento de ingresar a la unidad de cuidados intensivos sobresale la PaO2/FiO2 de 100 mmHg y el índice respiratorio (IR) > 2.4 con un ABC de 0.694 y 0.722 respectivamente. A las 96 horas de ingreso destaca PaO2/FiO2 de 145 mmHg, el IR >3 y la PaO2/PAO2 de 0.22 con un ABC de 0.846, 0.840 y 0.842 respectivamente. Conclusión: los gases arteriales medidos a las 96 horas de ingreso a la UCI son marcadores pronósticos para el desenlace fatal en la neumonía grave por SARS-CoV-2.

Abstract: Introduction: oxygenation indices we assess the function of the respiratory system of oxygenation and ventilation. Objective: to determine the value of arterial gases as a prognostic factor for the outcome of patients with severe SARS-CoV-2 pneumonia. Material and methods: retrospective, longitudinal, descriptive, analytical study. We included patients > 18 years with a diagnosis of SARS-CoV-2 pneumonia between 1 June and 31 December 2020. Patients were classified according to outcome: survivor or non-survivor. Descriptive statistics and parametric and non-parametric tests were used according to the case, ROC (Receiver Operating Characteristic Curve) curves were constructed to determine the cut-off points of arterial gases with the best sensitivity and specificity and the area under the curve (AUC) for the fatal outcome was determined. Results: we included 175 patients, 70.3% corresponded to the male sex, the mean age was 56 years (interquartile range 45-64). The survivor group included 51 patients and the non-survivor group 124 patients. When analyzing arterial gases at the time of admission to the ICU, paO2/FiO2 of 100 mmHg and respiratory index (RI) > 2.4 with ABC 0.694 and 0.722 respectively. At 96 hours of admission, PaO2/FiO2 of 145 mmHg stands out, the RI > 3 and the DA-aO2 of 0.22 with ABC 0.846, 0.840 and 0.842 respectively. Conclusion: arterial blood gases measured at 96 hours of ICU admission are prognostic markers for fatal outcome in severe SARS-CoV-2 pneumonia.

Resumo: Introdução: através dos índices de oxigenação avaliamos a função do sistema respiratório de oxigenação e ventilação. Objetivo: determinar o valor dos índices de oxigenação como fator prognóstico para o desfecho em pneumonia grave por SARS-CoV-2. Material e métodos: estudo retrospectivo, longitudinal, descritivo, analítico. Icluíram-se pacientes com mais de 18 anos de idade diagnosticados com pneumonia por SARS-CoV-2 entre 1º de junho e 31 de dezembro de 2020. Os pacientes foram classificados de acordo com o desfecho: sobreviventes ou não sobreviventes. Foram usadas estatística descritiva e testes paramétricos e não paramétricos de acordo com o caso, foram construídas curvas ROC (Receiver Operating Characteristic Curve) para determinar os pontos de corte da gasometria arterial com melhor sensibilidade e especificidade e determinou-se a área sob a curva (ABC) para o desfecho fatal. Resultados: incluíram-se 175 pacientes, 70.3% eram do sexo masculino, a média de idade foi de 56 anos (rango interquartil 45-64). O grupo sobrevivente incluiu 51 pacientes e o grupo não sobrevivente 124 pacientes. Na análise dos gases arteriais no momento da admissão na UTI, destacam-se a PaO2/FiO2 de 100 mmHg e o índice respiratório (IR) > 2.4 com AUC 0.694 e 0.722 respectivamente. Às 96 horas de internamento destaca-se PaO2/FiO2 145 mmHg, IR > 3 e PaO2/PAO2 de 0.22 com ABC 0.846, 0.840 e 0.842 respetivamente. Conclusão: os gases sanguíneos arteriais medidos 96 horas após a admissão na UTI são marcadores prognósticos para desfecho fatal em pneumonia grave por SARS-CoV-2.

Aplicação do plasma de baixa temperatura sob pressão atmosférica como adjuvante ao tratamento da mucosite oral / Application of low temperature atmospheric pressure plasma as an adjuvant in treatment oral mucositis

A mucosite oral é um quadro clínico que acomete frequentemente pacientes sob terapia antineoplásica na região de cabeça e pescoço e caracteriza-se por ulcerações na mucosa que geram intensa dor local, odinofagia, aumento do risco de infecções, do uso de antibióticos e do tempo de hospitalização. A correlação entre mucosite oral, infecção fúngica e o potencial de disseminação fúngica sistêmica foi recentemente descrita. Apesar do impacto desse quadro clínico sobre a qualidade e tempo de vida dos pacientes oncológicos, não há consenso sobre a profilaxia e o protocolo terapêutico. O plasma de baixa temperatura sobre pressão atmosférica (LTAPP) apresenta efeito antimicrobiano, anti-inflamatório e reparador tecidual, o que sugere que possa ser promissor no tratamento da mucosite oral. Os objetivos gerais deste projeto foram divididos em dois subprojetos: 1) Definir os melhores parâmetros in vitro com efeito antifúngico e não tóxico e avaliar o LTAPP no tratamento de lesão de mucosite oral em modelo murino de mucosite por quimioterapia e 2) avaliar se o tratamento com LTAPP pode prevenir a disseminação fúngica sistêmica em ratos a partir de infecção experimental de lesões de mucosite oral por Candida albicans. Para tal, foram incluídos no estudo 100 ratos (Rattus norvegicus) com 90 a 100 dias de idade. No subprojeto 1, a lesão de mucosite oral foi induzida por administração de 5 fluorouracila (5-FU), enquanto no subprojeto 2, utilizou-se 5-FU associada à cisplatina ambas associadas à aplicação tópica de ácido acético 50%. Para o subprojeto 1, os animais foram randomicamente divididos em 2 grupos experimentais (n=30): a) Grupo mucosite; b) Grupo mucosite tratado com LTAPP, avaliados após 1, 5 e 12 dias do tratamento. Durante o período experimental, as lesões foram fotografadas e a gravidade da mucosite classificada por meio da atribuição de escores. Após a eutanásia e o processamento, os cortes histológicos corados por hematoxilina-eosina (HE) foram analisados microscopicamente. Para o subprojeto 2, o estudo de disseminação sistêmica fúngica nos grupos de mucosite infectada com C. albicans tratado ou não com LTAPP foi conduzido pelo isolamento fúngico a partir de amostras de sangue total e macerado dos órgãos. Para tanto foram estudados 2 grupos de ratos (n=20): c) Grupo mucosite infectado com C. albicans e d) Grupo mucosite infectado com C. albicans tratada com LTAPP, avaliados após 24 e 72 h do tratamento. Para ambos os projetos, o melhor parâmetro in vitro foi selecionado, isto é aquele com maior atividade antifúngica e baixa toxicidade. Dessa forma, as lesões foram expostas ao LTAPP de hélio por 5 min na distância de 1,5 cm na potência de 1 W. Os resultados in vitro mostraram que o LTAPP teve efeito antifúngico e baixa toxicidade para células de mamíferos. Os resultados in vivo mostraram que 5-FU afetou a saúde geral dos animais, evidenciada pela perda de peso corporal. Em ambos os grupos, houve reparo tecidual após 12 dias do tratamento, com resolução quase completa da lesão, o que foi corroborado pelos achados microscópicos. O grupo LTAPP exibiu uma tendência maior de redução da lesão, após 12 dias de tratamento. Além disso, o LTAPP apresentou efeito inibitório sobre C. albicans após 5 minutos, de exposição, com redução da recuperação fúngica da língua após 24 h (p<0.05). A disseminação fúngica sistêmica foi reduzida significativamente após 24 e 72 h do tratamento. Com base nos resultados obtidos, conclui-se que o LTAPP é uma ferramenta promissora para futura aplicação clínica em pacientes com mucosite oral. (AU)

Oral mucositis is a clinical condition that frequently affects patients undergoing antineoplastic therapy in the head and neck region and is characterized by mucosal ulcerations that generate intense local pain, odynophagia, increased risks of infections, use of antibiotics and the length of hospital stay. The correlation among oral mucositis, fungal infection and the potential for systemic fungal dissemination has recently been described. Despite the impact of this clinical condition on the quality and life expectancy of cancer patients, there is no consensus on prophylaxis and the therapeutic protocols. Low temperature atmospheric pressure plasma (LTAPP) has antimicrobial, anti-inflammatory and tissue repairing effects, which suggests that it can be promising in the treatment of oral mucositis. The general objectives of this project were divided into two subprojects: 1) Define the best antifungal and non-toxic in vitro parameters and to evaluate the application of LTAPP in the treatment of oral mucositis in murine model for chemotherapy, and 2) to evaluate whether treatment with LTAPP can prevent systemic fungal dissemination in rats from experimental infection of oral mucositis lesions by Candida albicans. A total of 100 rats (Rattus norvegicus) aged 90 to 100 days were included in the study. In subproject 1, oral mucositis lesion was induced by administration of only 5- fluorouracil (5-FU), while in subproject 2, administration and systemic administration of 5-FU associated with cisplatin, both associated with topical application of 50% acetic acid. For subproject 1, the animals were randomly divided into 2 experimental groups (n=30):a) Mucositis group and b) Mucositis group treated with LTAPP evaluated after 1, 5 and 12 days of treatment. During the experimental period, the lesions were photographed, and the severity of mucositis was classified into scores. After euthanasia and processing, the histological cuts stained by hematoxylin-eosin (HE) were analyzed. For subproject 2, the study of fungal systemic dissemination in groups of mucositis infected with C. albicans treated or not with LTAPP was conducted by fungal isolation from whole blood and macerated organs. Therefore, 2 groups of rats (n=20) were studied: c) Mucositis group infected with C. albicans and d) Mucositis group infected with C. albicans treated with LTAPP, evaluated after 24 and 72 h of treatment. For both subprojects, the best in vitro parameter was selected, that is, the one with the greatest antifungal effect and low toxicity. Thus, the lesions were exposed to helium LTAPP for 5 min at a distance of 1.5 cm at power of 1 W. In vitro results showed that LTAPP has an antifungal effect and low toxicity. In vivo results showed that 5-FU affected the general health of animals evidenced by body weight loss. In both groups, there was tissue repair after 12 days of treatment, with almost complete resolution of the lesion, which was corroborated by the microscopic findings. LTAPP group showed a greater trend of reduction of lesion, after 12 days of the treatment. Furthermore, LTAPP showed inhibitory effect on C. albicans after 5 min of exposition, with reduction in fungal recovery from the tongue after 24 h (p<0.05). Reduction in fungal dissemination was observed after 24 and 72 h of LTAPP treatment (p<0.05). Based on the obtained results, it was concluded that LTAPP is a promising tool for future clinical application in patients with oral mucositis.(AU)

Quemadura por inhalación de humo e intoxicación por monóxido de carbono en paciente pediátrico

Introducción: El monóxido de carbono es uno de los mayores contaminantes de la atmósfera terrestre, su toxicidad es bien conocida por el ser humano. Las fuentes productoras responsables de aproximadamente 80 % de las emisiones de monóxido de carbono son los vehículos automotores que utilizan como combustible gasolina o diesel, los procesos industriales que utilizan compuestos del carbono y el fuego dentro de los hogares. Sus efectos tóxicos agudos incluida la muerte se han estudiados ampliamente, no así sus potenciales efectos adversos a largo plazo. Objetivo: Describir el comportamiento de la intoxicación aguda por monóxido de carbono en paciente pediátrico, su diagnóstico y tratamiento. Presentación del caso: paciente de 11 años de edad que sufre intoxicación aguda por monóxido de carbono. Ingresa en el Hospital Universitario procedente del primer nivel de atención médica como urgencia vital. Se estabiliza e identifican las alteraciones multisistémicas producidas por lesiones asociadas con la inhalación de humo y gases tóxicos en espacios cerrados. Se determina su correcto tratamiento. Conclusiones: La forma más pertinente de disminuir la morbilidad y la mortalidad en pacientes como el que se presenta, se basa en dos pilares: la correcta identificación y el acertado manejo para cada intoxicación. La aplicación de estos dos aspectos puede lograr un factor protector. Hay subregistro de la ocurrencia de los casos de intoxicación por monóxido de carbono que no son atendidos en los servicios de salud y de los que producen la muerte inmediata, por lo que es importante su diagnóstico y tratamiento oportuno.

Introduction: Carbon monoxide is one of the largest pollutants in the Earth's atmosphere, its toxicity is well known to humans. The producing sources responsible for approximately 80% of carbon monoxide emissions are motor vehicles that use gasoline or diesel as fuel, industrial processes that use carbon compounds and fire inside homes. Its acute toxic effects including death have been studied extensively, but its potential long-term adverse effects have not been studied. Objective: To describe the behavior of acute carbon monoxide poisoning in pediatric patients, their diagnosis and treatment. Case presentation: 11-year-old patient suffering from acute carbon monoxide poisoning. He is admitted to the University Hospital from the first level of medical care as a vital emergency. Multisystem alterations caused by lesions associated with the inhalation of smoke and toxic gases in enclosed spaces are stabilized and identified. Its correct treatment is determined. Conclusions: The most pertinent way to reduce morbidity and mortality in patients such as the one presented is based on two pillars: correct identification and correct management for each poisoning. The application of these two aspects can achieve a protective factor. There is underreporting of the occurrence of cases of carbon monoxide poisoning that are not treated in health services and those that cause immediate death, so their detection, diagnosis and timely treatment is important.

Ventilador mecânico invasivo de emergência resistente e de fácil manutenção / Robust, maintainable, emergency invasive mechanical ventilator

RESUMO Objetivo: Desenvolver um ventilador mecânico invasivo simples, resistente, seguro e eficiente que possa ser utilizado em áreas remotas do mundo ou zonas de guerra, em que a utilidade prática de equipamentos mais sofisticados é limitada por questões de manutenção, disponibilidade de peças, transporte e/ou custo. Métodos: O dispositivo implementa o modo de ventilação mandatória contínua com pressão controlada, complementado por um simples modo assisto-controlado. Pode-se também utilizar a pressão positiva contínua nas vias aéreas. Ao se evitar o fluxo contínuo de oxigênio ou ar, minimiza-se o consumo de gases comprimidos. As taxas respiratórias e as relações de tempo de inspiração e expiração são determinadas eletronicamente. Além disso, conta com um alarme de apneia/falta de energia. Resultados: Os perfis de pressão foram medidos para uma série de condições, sendo considerados ajustáveis dentro de uma margem de erro de ± 2,5cmH2O, e foram considerados bem estáveis dentro dessa variação durante um período de 41 horas. Os parâmetros de tempo do ciclo respiratório foram precisos dentro de alguns pontos percentuais durante o mesmo período. O dispositivo foi testado quanto à durabilidade por um período equivalente a 4 meses. Os testes químicos e biológicos não conseguiram identificar qualquer contaminação do gás por compostos orgânicos voláteis ou micro-organismos. Em comparação com um ventilador bem estabelecido, o teste de ventilação em um animal de grande porte mostrou que este poderia ser ventilado adequadamente durante um período de 60 minutos, sem quaisquer efeitos negativos perceptíveis durante o período subsequente de 24 horas. Conclusão: Este projeto de ventilador pode ser viável após novos testes em animais e aprovação formal pelas autoridades competentes, para aplicação clínica nas circunstâncias atípicas anteriormente mencionadas.

ABSTRACT Objective: To develop a simple, robust, safe and efficient invasive mechanical ventilator that can be used in remote areas of the world or war zones where the practical utility of more sophisticated equipment is limited by considerations of maintainability, availability of parts, transportation and/or cost. Methods: The device implements the pressure-controlled continuous mandatory ventilation mode, complemented by a simple assist-control mode. Continuous positive airway pressure is also possible. The consumption of compressed gases is minimized by avoiding a continuous flow of oxygen or air. Respiratory rates and inspiration/expiration time ratios are electronically determined, and an apnea/power loss alarm is provided. Results: The pressure profiles were measured for a range of conditions and found to be adjustable within a ± 2.5cmH2O error margin and stable well within this range over a 41-hour period. Respiratory cycle timing parameters were precise within a few percentage points over the same period. The device was tested for durability for an equivalent period of four months. Chemical and biological tests failed to identify any contamination of the gas by volatile organic compounds or microorganisms. A ventilation test on a large animal, in comparison with a well established ventilator, showed that the animal could be adequately ventilated over a period of 60 minutes, without any noticeable negative aftereffects during the subsequent 24-hour period. Conclusion: This ventilator design may be viable, after further animal tests and formal approval by the competent authorities, for clinical application in the abovementioned atypical circumstances.

5° Congreso Nacional y 1° Internacional de Ciencias Ambientales "Las Ciencias Ambientales en el Antropoceno". Emisiones generadas y evitadas / 5th National and 1st International Congress of Environmental Sciences "Environmental Sciences in the Anthropocene". Emissions generated and avoided

RESUMEN Las actividades académicas, como los congresos, son muy importantes para la investigación y el desarrollo; sin embargo, las emisiones de carbono derivadas de la realización de eventos presenciales han mostrado estar muy por encima de las que producen eventos en línea. El objetivo de este trabajo fue estimar las emisiones generadas por el 5º Congreso Nacional y 1º Internacional de Ciencias Ambientales "Las Ciencias Ambientales en el Antropoceno", celebrado virtualmente, en su mayor parte. Se estimaron las emisiones del uso directo de computadores y de software (emisiones de los computadores, emisiones de la transferencia de los datos) y las emisiones de otras fuentes (reuniones de los organizadores, búsquedas y visitas a la página Web, uso de monitores externos y lámparas), así como las emisiones evitadas por transporte aéreo y terrestre. El congreso emitió 4,8 tCO2eq y evitó 33 tCO2eq. El desarrollo de eventos online o híbridos es más sostenible ambientalmente y podría ser más accesibles, a un mayor número de personas.

ABSTRACT Academic activities such as conferences are very important for research and development, however, carbon emissions derived from face-to-face events have been shown to be much higher than those produced by online events. The aim of this work was to estimate CO2 emissions generated by the 5th National Congress and 1st International Congress of Environmental Sciences "Environmental Sciences in the Anthropocene". Emissions from direct use of computers and software (emissions from computers, emissions from data transfer) and emissions from other sources (meetings of the organizers, searches and visits to the website, use of external monitors and lamps), as well as emissions avoided by air and land transport. The congress emitted 4.8 tCO2eq and avoided 33 tCO2eq. The development of online or hybrid events is more environmentally sustainable and could be more accessible to a greater number of people.

Alteraciones del estado ácido básico en pacientes adultos con insuficiencia renal crónica / Acid-base status alterations in adult patients with chronic renal failure

RESUMEN Introducción: el portador de insuficiencia renal crónica puede presentar diversas alteraciones del estado ácido básico, siendo la acidosis metabólica la más frecuente. Objetivos: describir las características demográficas y clínicas y las alteraciones del estado ácido básico de pacientes adultos que ingresan con insuficiencia renal crónica en dos centros hospitalarios del Paraguay. Metodología: se aplicó un diseño observacional, descriptivo, transversal. Se incluyó a sujetos adultos de ambos sexos, portadores de insuficiencia renal crónica, que acudieron al Hospital Nacional (Itauguá) y Hospital Militar (Asunción) entre abril y noviembre del 2021. Se midieron variables antropométricas, clínicas y laboratoriales al ingreso. Los datos se sometieron a estadística descriptiva con el programa Epi Info 7™. El estudio contó con la aprobación del Comité de Ética de la Universidad Privada del Este, Paraguay. Resultados: se incluyó a 148 sujetos, siendo 78 (52,7 %) varones con edad media 58 ± 16 años y 70 (47,3 %) mujeres con edad media 54 ± 17 años. Las etiologías más frecuentes de la insuficiencia renal crónica fueron la diabetes mellitus e hipertensión arterial (44,5 %). Se detectó 12 sujetos (8,1 %) con gasometría normal. La alteración del estado ácido básico más frecuente fue la acidosis metabólica (87,2 %), predominando en este grupo los casos con brecha aniónica normal. Conclusiones: las alteraciones del estado ácido básico predominantes en pacientes con insuficiencia renal crónica fue la acidosis metabólica con brecha aniónica normal. Se sugiere aplicar los cálculos de los mecanismos compensadores para llegar al diagnóstico certero de estas alteraciones metabólicas.

ABSTRACT Introduction: the carrier of chronic renal failure can present various alterations of the basic acid state, being the metabolic acidosis the most frequent. Objectives: to describe the demographic and clinical characteristics and alterations in the acid-base status of adult patients admitted with chronic renal failure in two hospitals in Paraguay. Methodology: an observational, descriptive, cross-sectional design was applied. Adult subjects of both sexes, carriers of chronic renal failure, who attended the National Hospital (Itauguá) and the Military Hospital (Asunción) between April and November 2021 were included. Anthropometric, clinical and laboratory variables were measured at admission. The data was submitted to descriptive statistics with the Epi Info 7™ program. The study was approved by the Ethics Committee of the Universidad Privada del Este, Paraguay. Results: 148 subjects were included, being 78 (52.7 %) men with a mean age of 58 ± 16 years and 70 (47.3 %) women with a mean age of 54 ± 17 years. The most frequent etiologies of chronic renal failure were diabetes mellitus and arterial hypertension (44.5 %). 12 subjects (8.1 %) with normal blood gases were detected. The most frequent alteration of the acid-base status was metabolic acidosis (87.2 %), with cases with normal anion gap predominating in this group. Conclusions: the predominant acid-base status alterations in patients with chronic renal failure was metabolic acidosis with normal anion gap. It is suggested to apply the calculations of the compensatory mechanisms to arrive at the accurate diagnosis of these metabolic alterations.

The effect of different body positions after pars plana vitrectomy and inert gas filling for rhegmatogenous retinal detachment / 中华眼底病杂志

Objective:To compare and observe the curative effect of different body positions after pars plana vitrectomy (PPV) combined with inert gas filling for rhegmatogenous retinal detachment (RRD).Methods:A retrospective clinical study. From October 2019 to September 2021, 192 eyes of 192 RRD patients who were diagnosed and received PPV combined with inert gas filling in Qingdao Eye Hospital of Shandong First Medical University were included in the study. Best corrected visual acuity (BCVA), intraocular pressure, ultra-wide-angle fundus photography, optical coherence tomography, and B-mode ultrasonography were performed in all affected eyes. The BCVA examination was performed using a standard logarithmic visual acuity chart, which was converted into logarithm of the minimum angle of resolution (logMAR) visual acuity during statistics. According to the post-operative position requirements, the affected eyes were divided into the face-down positioning group and the adjustable positioning group, with 97 eyes in 97 patients and 95 eyes in 95 patients, respectively. Age ( Z=0.804), course of disease ( Z=-0.490), eye type ( χ2=0.175), logMAR BCVA( Z=-0.895), intraocular pressure ( Z=0.178), lens status ( χ2=1.090), number of detached clocks ( Z=0.301) and macular involvement ( χ2=0.219), number of holes ( Z=-1.051) and number of lower holes ( χ2=0.619) were compared, there was no significant difference ( P>0.05). The gender composition ratio was compared, and the difference was statistically significant ( χ2=5.341, P<0.05). The follow-up time after surgery was more than 3 months. The retinal reattachment rate in one operation, the improvement of BCVA and the incidence of complications were observed. The independent sample Mann-Whitney test was used for the comparison of continuous variables between groups; the χ2 test was used for the comparison of categorical variables. Results:In the face-down positioning group and the adjustable positioning group, retinal reattachment in one operation was performed in 92 (94.8%, 92/97) and 89 (93.7%, 89/95) eyes, respectively; logMAR BCVA was 0.45±0.34, 0.41±0.21. There was no significant difference in the retinal reattachment rate in one operation ( χ2=0.120, P=0.729) and logMAR BCVA ( Z=-0.815, P=0.416) between the two groups. After surgery, the intraocular pressure increased in 11 (11.3%, 11/97) and 5 (5.3%, 5/95) eyes in the face-down positioning group and the adjustable positioning group, respectively; the secondary epimacular membrane was 2 (2.1%, 2/97), 3 (3.2%, 3/95) eyes. There was no significant difference in the incidence of elevated intraocular pressure and secondary epimacular membrane between the two groups after surgery ( χ2=2.320, 0.227; P=0.128, 0.634). Conclusion:It is safe and effective to adopt adjustable positioning after PPV combined with inert gas filling for RRD, which is equivalent to the effect of face-down positioning.

New insight into application and function of air or gas for vitreoretinal surgery / 中华眼底病杂志

At present, tamponade agent which being used in retinal surgery is mainly sterile air, gas and silicone oil. Sterile air is mostly used in the treatment of simple retinal detachment. Gas or silicone oil as tamponade is greatly applied for complicated retinal detachment. In recent years, with the application of micro-invasive vitrectomy under a wide-angle viewing system and perioperative anti-vascular endothelial growth factor drugs, application of intraocular filling materials also has changed. The application of silicone oil is significantly reduced. Percentage rate of gas as tamponade for retinal detachment is reduced. The application of sterile air as tamponade is rising. With selecting indication carefully and picking up the suitable air or gas, doctor will reduce the workload. It will also reduce the social burden and benefit patients.