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Background: During lifespan of reverse osmosis systems applied in seawater desalination plants, a common phenomenon of undesirable growth and accumulation of biological material known as biofouling occurs. Microbial cells are first settlers, attaching and enclosing themselves in extracellular polymeric substances –biomass accumulation usually referred to as microfouling or biofilms, which becomes a serious issue when having a detrimental effect on materials or hampering industrial processes. Thus, control of microfouling on reverse osmosis membranes is crucial since chemical and physical treatments are usually costly and ineffective. In this context, even though microorganisms are the source of the problem, they can also provide possible solutions due to their capacity to produce secondary metabolites, being several of these competition mediators secreted compounds (i.e., bioactive molecules) produced during the stationary phase (e.g., lipases, proteases, DNases and other enzymes with alginate lyase and xanthine oxidases). Such bioactive substances can be utilized against the development of biofilms. Considering biofouled surfaces a niche for complex microbial interactions, here we have used reverse osmosis membranes and cartridge filters applied in a seawater desalination plant as a source for the isolation of bacteria with anti-fouling potential, among other biotechnological applications. Results: We obtained 27 bacterial isolates able to secrete exoenzymes displaying a wide array of bioactivity such as lipases, alginases, and glucosidases, among others. Additionally, we showed two main candidates able to inhibit the growth of common microbial colonizers of ROM and cartridge filter. Conclusions: These results highlight the potential biotechnological application of bioactive molecules against biofouling formation.How to cite: Vera-Villalobos H, Cortes-Martinez A, Gonzalez-Gutierrez Á, et al. Reverse osmosis membranes applied in seawater desalination plants as a source of bacteria with antifouling activity: Isolation, biochemical and molecular characterization. Electron J Biotechnol 2023;66. https://doi.org/10.1016/j.ejbt.2023.09.003.

Background Patients with coronavirus disease 2019 (COVID-19) could develop severe disease requiring admission to the intensive care unit (ICU). This article presents a novel method that predicts whether a patient will need admission to the ICU and assesses the risk of in-hospital mortality by training a deep-learning model that combines a set of clinical variables and features in chest radiographs. Methods This was a prospective diagnostic test study. Patients with confirmed severe acute respiratory syndrome coronavirus 2 infection between March 2020 and January 2021 were included. This study was designed to build predictive models obtained by training convolutional neural networks for chest radiograph images using an artificial intelligence (AI) tool and a random forest analysis to identify critical clinical variables. Then, both architectures were connected and fine-tuned to provide combined models. Results 2552 patients were included in the clinical cohort. The variables independently associated with ICU admission were age, fraction of inspired oxygen (FiO2) on admission, dyspnoea on admission and obesity. Moreover, the variables associated with hospital mortality were age, FiO2 on admission and dyspnoea. When implementing the AI model to interpret the chest radiographs and the clinical variables identified by random forest, we developed a model that accurately predicts ICU admission (area under the curve (AUC) 0.92±0.04) and hospital mortality (AUC 0.81±0.06) in patients with confirmed COVID-19. Conclusions This automated chest radiograph interpretation algorithm, along with clinical variables, is a reliable alternative to identify patients at risk of developing severe COVID-19 who might require admission to the ICU.

Resumen: Objetivos: Valorar si el peso ≤ 2,5 kg supone un incremento en la morbimortalidad de la cirugía cardiaca neonatal bajo circulación extracorpórea (CEC) y caracterizar este grupo de pacientes. Métodos: Estudio retrospectivo de todos los neonatos sometidos a una primera cirugía cardiaca con CEC entre 2007 y 2019, analizando los factores independientes de morbimortalidad. Resultados: Cuarenta y nueve pacientes ≤ 2,5 kg vs. 246 > 2,5 kg, sin diferencias significativas con relación a la edad en el momento de la reparación, aunque sí en la prematuridad y el sexo femenino, mayores en ≤ 2,5 kg. Los diagnósticos más frecuentes fueron hipoplasia del arco y truncus en ≤ 2,5 kg, y transposición de grandes arterias e hipoplasia de arco en > 2,5 kg. El tiempo de CEC y el uso de parada circulatoria fueron significativamente mayores en ≤ 2,5 kg. A pesar de que el grupo ≤ 2,5 kg tuvo una mortalidad mayor (22,4 vs. 8,1%; p 2,5 kg. El análisis de la prematuridad no mostró incremento significativo de morbimortalidad. Conclusiones: A pesar de los avances en el manejo peri-extracorpórea en ≤ 2,5 kg, disminuyendo la mortalidad en algunas enfermedades, el bajo peso sigue asociándose a aumento de mortalidad. El momento de cuándo intervenir deberá individualizarse por paciente, diagnóstico y resultados del propio centro. Abstract: Objectives: Evaluate whether a weight ≤2.5 kg carries an increase in morbi-mortality in neonatal cardiac surgery under cardiopulmonary bypass (CPB) and stablish the profile of these patients. Methods: Retrospective study of the neonates who underwent the first cardiac surgery under CPB between 2007-2019, analyzing independent risk factors for morbi-mortality. Results: Group of patients ≤2.5 kg: n = 49. Group of patients >2.5 kg: n = 246. No statistical differences found in age, although there were in prematurity and female sex, which were more frequent in ≤2.5 kg. Most frequent diagnosis in ≤2.5 kg was arch hypoplasia and truncus versus transposition of the great arteries (TGA) and arch hypoplasia in >2.5 kg. Cardiopulmonary bypass time and the use of circulatory arrest were significantly higher in ≤2.5 kg. Although ≤2.5 kg group presented a greater mortality (22.4 vs 8.1% p

Recent climatic trends, such as warming temperatures, decrease in rainfall, and extreme weather events (e.g., heatwaves), are negatively affecting the performance of forests. In northern Patagonia, such conditions have caused tree growth reduction, crown dieback, and massive die-back events. However, studies looking at these consequences in the southernmost temperate forest (Nothofagus betuloides and Nothofagus pumilio) are much scarcer, especially in southernmost South America (SSA). These forests are also under the influence of the positive phase of Antarctic Oscillation (AAO, also known as Southern Annular Mode, SAM) that has been associated with increasing trends in temperature, drought, and extreme events in the last decades. This study evaluated the growth patterns and the climatic response of eight new tree-ring chronologies from Nothofagus species located at the upper treeline along different environmental gradients in three study areas: Punta Arenas, Yendegaia National Park, and Navarino Island in SSA. The main modes of the ring-width index (RWI) variation were studied using principal component analysis (PCA). We found that PC1 has the higher loadings for sites with precipitation values over 600 mm/yr, PC2 with N. betuloides sites, and PC3 with higher loadings for sites with precipitation values below 600 mm/yr. Our best growth-climate relationships are between N. betuloides and AAO and the most northeastern site of N. pumilio with relative humidity (which coincides with heatwaves and extreme drought). The climatic signals imprinted in the southernmost forests are sensitive to climatic variability, the climate forcing AAO, and the effects of climate change in the last decades.

Objetivo: El momento de reparar electivamente la situación Fallot genera controversia. Comparamos pacientes con reparación completa antes/después de 90 días de vida, analizando diferencias en mortalidad, morbilidad hospitalaria y necesidad de reintervención. Métodos Estudio retrospectivo de aquellos operados en nuestro centro para reparación completa de situación Fallot 90 días (p = 0,002). Ductus permeable: 40% en ≤90 días versus 10% en >90 días (p 90 días. En los últimos 3 años sin paliaciones. Diferencia estadísticamente significativa en tiempo de pinzado aórtico (menor en grupo ≤90 días). También en tiempos medianos de intubación, estancia en intensivos y hospitalización, mayores en el grupo ≤90 días. No hay diferencias en mortalidad global, ni fallecieron neonatos. Complicaciones perioperatorias: un 70% en ≤90 días versus 43% en >90 días (p = 0,01). No hubo diferencias en mortalidad ni en necesidad de reintervención en el seguimiento. Conclusiones: En nuestra experiencia, la reparación de la situación Fallot antes/después de 90 días (neonatos incluidos) no conlleva diferencias en mortalidad hospitalaria, pero sí aumento en morbilidad cuando se realiza antes del tercer mes. Tampoco hay diferencias en mortalidad ni en necesidad de reintervención en el seguimiento. Pospondremos la reparación completa electiva a más de 90 días, reservando la precoz para pacientes sintomáticos y evitando la paliación.

Recent evidence shows that most Patagonian glaciers are receding rapidly. Due to the lack of in situ long-term meteorological observations, the understanding of how glaciers are responding to changes in climate over this region is extremely limited, and uncertainties exist in the glacier surface mass balance model parameterizations. This precludes a robust assessment of glacier response to current and projected climate change. An issue of central concern is the accurate estimation of precipitation phase. In this work, we have assessed spatial and temporal patterns in snow accumulation in both the North Patagonia Icefield (NPI) and South Patagonia Icefield (SPI). We used a regional climate model, RegCM4.6 and four Phase Partitioning Methods (PPM) in addition to short-term snow accumulation observations using ultrasonic depth gauges (UDG). Snow accumulation shows that rates are higher on the west side relative to the east side for both icefields. The values depend on the PPM used and reach a mean difference of 1,500 mm w.e., with some areas reaching differences higher than 3,500 mm w.e. These differences could lead to divergent mass balance estimations depending on the scheme used to define the snow accumulation. Good agreement is found in comparing UDG observations with modeled data on the plateau area of the SPI during a short time period; however, there are important differences between rates of snow accumulation determined in this work and previous estimations using ice core data at annual scale. Significant positive trends are mainly present in the autumn season on the west side of the SPI, while on the east side, significant negative trends in autumn were observed. Overall, for the rest of the area and during other seasons, no significant changes can be determined. In addition, glaciers with positive and stable elevation and frontal changes determined by previous works are related to areas where snow accumulation has increased during the period 2000–2015. This suggests that increases in snow accumulation are attenuating the response of some Patagonian glaciers to warming in a regional context of overall glacier retreat.

Abstract Background Although insulin resistance (IR) is among the most frequent and pathogenically relevant complications accompanying childhood obesity, its role in modulating and exacerbating obesity pathophysiology has not yet been completely clarified. Methods To get deeper insights into the interplay between childhood obesity and IR, we leveraged a comprehensive experimental design based on a combination of observational data, in vivo challenge tests (i.e., oral glucose tolerance test), and ex vivo assays (i.e., incubation of erythrocytes with insulin) using a population comprising children with obesity and IR, children with obesity without IR, and healthy controls, from whom plasma and erythrocyte samples were collected for subsequent metabolomics analysis. Results Children with concomitant IR showed exacerbated metabolic disturbances in the crosstalk between endogenous, microbial, and environmental determinants, including failures in energy homeostasis, amino acid metabolism, oxidative stress, synthesis of steroid hormones and bile acids, membrane lipid composition, as well as differences in exposome-related metabolites associated with diet, exposure to endocrine disruptors, and gut microbiota. Furthermore, challenge tests and ex vivo assays revealed a deleterious impact of IR on individuals’ metabolic flexibility, as reflected in blunted capacity to regulate homeostasis in response to hyperinsulinemia, at both systemic and erythroid levels. Conclusions Thus, we have demonstrated for the first time that metabolite alterations in erythrocytes represent reliable and sensitive biomarkers to disentangle the metabolic complexity of IR and childhood obesity. This study emphasizes the crucial need of addressing inter-individual variability factors, such as the presence of comorbidities, to obtain a more accurate understanding of obesity-related molecular mechanisms.

Abstract Background Insulin resistance is a frequent precursor of typical obesity and metabolic syndrome complications. However, accurate diagnosis remains elusive because of its pathophysiological complexity and heterogeneity. Herein, we have explored the utility of insulin secretion dynamics in response to an oral glucose tolerance test as a surrogate marker to identify distinct metabotypes of disease severity. Methods The study population consisted of children with obesity and insulin resistance, stratified according to the post-challenge insulin peak timing (i.e., early, middle, and late peak), from whom fasting and postprandial plasma and erythrocytes were collected for metabolomics analysis. Results Children with late insulin peak manifested worse cardiometabolic health (i.e., higher blood pressure, glycemia, and HOMA-IR scores) than early responders. These subjects also showed more pronounced changes in metabolites mirroring failures in energy homeostasis, oxidative stress, metabolism of cholesterol and phospholipids, and adherence to unhealthy dietary habits. Furthermore, delayed insulin peak was associated with impaired metabolic flexibility, as reflected in compromised capacity to regulate mitochondrial energy pathways and the antioxidant defense in response to glucose overload. Conclusions Altogether, these findings suggest that insulin resistance could encompass several phenotypic subtypes characterized by graded disturbances in distinctive metabolic derangements occurring in childhood obesity, which serve as severity predictive markers.

Abstract Over the past two decades, more frequent and intense climate events have seriously threatened the operation of water transfer projects in the Pacific Rim region. However, the role of climatic change in driving runoff variations in the water source areas of these projects is unclear. We used tree-ring data to reconstruct changes in the runoff of the Hanjiang River since 1580 CE representing an important water source area for China’s south-north water transfer project. Comparisons with hydroclimatic reconstructions for the southwestern United States and central Chile indicated that the Pacific Rim region has experienced multiple coinciding droughts related to ENSO activity. Climate simulations indicate an increased likelihood of drought occurrence in the Pacific Rim region in the coming decades. The combination of warming-induced drought stresses with dynamic El Niño (warming ENSO) patterns is a thread to urban agglomerations and agricultural regions that rely on water transfer projects along the Pacific Rim.

Abstract Early breast cancer patients often experience relapse due to residual disease after treatment. Liquid biopsy is a methodology capable of detecting tumor components in blood, but low concentrations at early stages pose challenges. To detect them, next-generation sequencing has promise but entails complex processes. Exploring larger blood volumes could overcome detection limitations. Herein, a total of 282 high-volume plasma and blood-cell samples were collected for dual ctDNA/CTCs detection using a single droplet-digital PCR assay per patient. ctDNA and/or CTCs were detected in 100% of pre-treatment samples. On the other hand, post-treatment positive samples exhibited a minimum variant allele frequency of 0.003% for ctDNA and minimum cell number of 0.069 CTCs/mL of blood, surpassing previous investigations. Accurate prediction of residual disease before surgery was achieved in patients without a complete pathological response. A model utilizing ctDNA dynamics achieved an area under the ROC curve of 0.92 for predicting response. We detected disease recurrence in blood in the three patients who experienced a relapse, anticipating clinical relapse by 34.61, 9.10, and 7.59 months. This methodology provides an easily implemented alternative for ultrasensitive residual disease detection in early breast cancer patients.

La enfermedad de Hailey-Hailey es una enfermedad minoritaria dermatológica de origen genético. Cursa con la aparición de lesiones ampollosas, especialmente en áreas de fricción y pliegues cutáneos, como la región inguinal, axilar y el cuello. Se presenta el caso de una mujer refractaria a diversos fármacos inmunosupresores. El Servicio de Dermatología solicita al Servicio de Farmacia la elaboración de una fórmula tópica de gentamicina para el manejo de las lesiones. Desde el Servicio de Farmacia se elabora una pomada de gentamicina sulfato al 0,5%. Tras 4 semanas de tratamiento, se observó la resolución total de las lesiones submamarias y una disminución en el tamaño de las lesiones axilares, antecubitales y poplíteas. A los 3 meses, todas las lesiones se resolvieron completamente, permitiendo reducir la dosis de apremilast. A los 6 meses, la respuesta clínica se mantuvo sin reacciones adversas.

Abstract Introduction The National Psoriasis Foundation (NPF) recommends evaluating patient response to treatment at week 12, with a target response of ≤ 1% body surface area (BSA) affected by plaque psoriasis and an acceptable response of BSA ≤ 3% or ≥ 75% improvement. This post hoc analysis compared the achievement of NPF target and acceptable responses for ixekizumab (IXE) versus other biologics. Methods Outcomes were evaluated at week 12 for patients with moderate-to-severe plaque psoriasis from four head-to-head randomized clinical trials (RCTs; UNCOVER-2, UNCOVER-3, IXORA-R, and IXORA-S) and one real-world prospective observational study (Psoriasis Study of Health Outcomes; PSoHO). RCT patients were treated with IXE or etanercept (ETN; UNCOVER-2/3), guselkumab (GUS; IXORA-R), or ustekinumab (UST; IXORA-S). PSoHO patients were treated with anti-interleukin (IL)-17A biologics (IXE, secukinumab, SEC) and other approved biologics for the treatment of plaque psoriasis. Patients with missing outcomes were imputed as non-responder imputation. For RCT data, statistical comparisons between treatment groups were performed using Fisher’s exact test with no multiplicity adjustments. For real-world data, adjusted comparative analyses were performed using frequentist model averaging (FMA) and reported as odds ratio (OR). Results Across the four head-to-head clinical trials analyzed, significantly higher proportions of patients achieved target and acceptable responses at week 12 with IXE versus ETN, GUS, or UST. Likewise, the proportion of PSoHO patients achieving target and acceptable response at week 12 was higher with IXE compared with other individual biologics. Adjusted comparative analyses showed that IXE had significantly greater odds of target and acceptable response at week 12 versus SEC, GUS, risankizumab (RIS), adalimumab (ADA), UST, and tildrakizumab (TILD) and numerically greater odds of target and acceptable response at week 12 versus brodalumab (BROD). Conclusion Across both clinical studies and real-world settings, more patients treated with IXE achieved NPF target and acceptable responses at week 12 compared with those treated with other biologics. Trial Registration UNCOVER-2 (NCT01597245); UNCOVER-3 (NCT01646177); IXORA-R (NCT03573323); IXORA-S (NCT02561806); PSoHO (EUPAS24207).