37 research outputs found

    A multi-objective optimization model to plan city-scale water systems with economic and environmental objectives: a case study in Santiago, Chile

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    Climate Change and its effects in water scarcity has become an important challenge for cities with water management problems. These problems require an integral planning of the city, which can be supported by optimization. The main goal of the research is to provide a regional optimization model for water networks, including new treatment options. The model is formulated as a multi-objective mixed-integer programming problem, focused on environmental and economic impact of the network, minimizing water extracted from natural sources and total cost. The formulation is developed with the goal-programming methodology. The model covers a complete existing city-scale water network, including 4 different options of water reuse within the city: drinking water, fresh water, irrigation, and discharge in natural courses. The case study is Santiago, capital of Chile, which is the political, economic, and institutional center of Chile. If both objective functions have equal importance to configure the solution, the following ideas characterize the optimal water network: (i) it is more environmentally and economically convenient to reuse water within the network rather than recycling water to the natural source; (ii) the reuse of water is preferred in the form of irrigation and drinking qualities rather than industrial qualities to reduce transport costs, and (iii) the modification of the current treatment plants is preferred, because of the high cost of installation of new plants. An environmental and cost-effective solution for Santiago, Chile, can reduce the source water extraction in 35.7%. The model can be implemented in other contexts, providing orientations to decision-makers so as to plan city-scale water networks with simultaneous environmental and economic considerations

    Effects of hemorrhage on gastrointestinal oxygenation

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    Objectives: (1) To demonstrate that metabolic parameters are better indicators of tissue hypoxia than regional and whole oxygen consumption (VO2). (2) To compare intramucosal pH (pHi) in different gastrointestinal segments. Design: Prospective, interventional study. Setting: Research laboratory at a university center. Subjects: Fourteen anesthetized, mechanically ventilated dogs. Interventions: Twenty milliliters per kilogram bleeding. Measurements and main results: We placed pulmonary, aortic and mesenteric venous catheters, and an electromagnetic flow probe in the superior mesenteric artery, and gastric, jejunal and ileal tonometers to measure flows, arterial and venous blood gases and lactate, and intramucosal PCO2. We calculated systemic and intestinal oxygen transport (DO2) and consumption (VO2), pHi and arterial minus intramucosal PCO2 (ΔPCO2). Then, we bled the dogs and repeated the measurements after 30 min. Systemic and intestinal DO2 fell (26.0±7.3 versus 8.9±2.6 and 71.9±17.3 versus 24.6±9.6 ml/min per kg, respectively, p<0.0001). Systemic and intestinal VO2 remained unchanged (5.5±1.3 versus 5.4±1.3 and 15.7±5.0 versus 14.9±5.3 ml/min per kg, respectively). Gastric, jejunal and ileal pHi (7.13±0.11 versus 6.96±0.17, 7.18±0.06 versus 6.97±0.15, 7.12±0.11 versus 6.94±0.14, p<0.05) and ΔPCO2 (21±13 versus 35±23, 15±5 versus 33±16, 23±17 versus 38±20, p<0.05) changed accordingly. Arterial and mesenteric venous lactate and their difference, rose significantly (1.7±0.9 versus 3.7±1.4 and 1.8±0.8 versus 4.3±1.5 mmol/l, 0.1±0.6 versus 0.6±0.7 mmol/l, p<0.05). Conclusions: During hemorrhage, systemic and intestinal VO2 remained stable. However, hyperlactatemia and intramucosal acidosis evidenced anaerobic metabolism. pHi changes paralleled in the three intestinal segments.Facultad de Ciencias Médica

    The Response to Biologics is Better in Patients with Severe Asthma Than in Patients with Asthma–COPD Overlap Syndrome

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    Although biologics have demonstrated to be effective in T2-high asthma patients, there is little experience with these drugs in asthma-COPD overlap (ACO). The aim of this study was to compare the effectiveness of biologics in these two conditions. We included 318 patients (24 ACO and 297 asthma) treated with monoclonal antibodies and followed for at least 12 months Omalizumab was the most frequently employed biologic agent both in patients with ACO and asthma. Asthma control test (ACT) scores after at least 12 months of biologic therapy were not significantly different between groups. The percentage of patients with >= 1 exacerbation and >= 1 corticosteroid burst was significantly higher in ACO patients (70.8 vs 27.3 and 83.3% vs 37.5%, respectively), whereas the percentage of controlled patients (with no exacerbations, no need for corticosteroids and ACT >= 20) was significantly lower (16.7% vs 39.7%). In conclusion, this report suggests that patients with ACO treated with biologics reach worse outcomes than asthma patients

    Impact of pre- and/or post-autologous stem cell transplantation exposure to brentuximab vedotin on survival outcomes in patients with high-risk Hodgkin lymphoma

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    The AETHERA trial demonstrated that brentuximab vedotin (BV) consolidation after autologous stem cell transplantation (ASCT) in patients with Hodgkin lymphoma (HL) at high risk of relapse/progression increases progression-free survival (PFS). Patients previously exposed to BV were excluded from that trial. However, BV alone or in combination with chemotherapy is frequently used as front-line treatment and/or pre-ASCT salvage therapy. We analyzed data from 156 patients with high-risk HL who underwent ASCT with (BV-CON, n?=?62) or without (non-BV, n?=?94) BV consolidation. Fifty-seven patients received BV-based salvage regimens before ASCT. The 3-year overall survival and PFS for all patients were 91.6% and 70.0%, respectively. Multivariate analysis showed that BV-CON was associated with better PFS (HR 0.39, p?=?0.01), whereas positive PET at transplant leaded to worse PFS (HR 2.71, p?=?0.001). BV-CON improved PFS in PET-positive patients (72.2% vs. 43.0%, p?=?0.05), with a beneficial trend observed in PET negative (88.8% vs. 75.2%, p?=?0.09). BV-CON patients with or without BV exposure pre-ASCT had a significantly better PFS than non-BV with or without BV pretransplant treatment (HR 0.36, p?=?0.004). The efficacy of real-life BV consolidation therapy was similar to that in the AETHERA trial. This therapeutic strategy improves survival independently of BV exposure prior to ASCT.© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature

    Complement component C4 structural variation and quantitative traits contribute to sex-biased vulnerability in systemic sclerosis

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    Altres ajuts: Fondo Europeo de Desarrollo Regional (FEDER), "A way of making Europe".Copy number (CN) polymorphisms of complement C4 play distinct roles in many conditions, including immune-mediated diseases. We investigated the association of C4 CN with systemic sclerosis (SSc) risk. Imputed total C4, C4A, C4B, and HERV-K CN were analyzed in 26,633 individuals and validated in an independent cohort. Our results showed that higher C4 CN confers protection to SSc, and deviations from CN parity of C4A and C4B augmented risk. The protection contributed per copy of C4A and C4B differed by sex. Stronger protection was afforded by C4A in men and by C4B in women. C4 CN correlated well with its gene expression and serum protein levels, and less C4 was detected for both in SSc patients. Conditioned analysis suggests that C4 genetics strongly contributes to the SSc association within the major histocompatibility complex locus and highlights classical alleles and amino acid variants of HLA-DRB1 and HLA-DPB1 as C4-independent signals

    Clustering COVID-19 ARDS patients through the first days of ICU admission. An analysis of the CIBERESUCICOVID Cohort

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    Background Acute respiratory distress syndrome (ARDS) can be classified into sub-phenotypes according to different inflammatory/clinical status. Prognostic enrichment was achieved by grouping patients into hypoinflammatory or hyperinflammatory sub-phenotypes, even though the time of analysis may change the classification according to treatment response or disease evolution. We aimed to evaluate when patients can be clustered in more than 1 group, and how they may change the clustering of patients using data of baseline or day 3, and the prognosis of patients according to their evolution by changing or not the cluster.Methods Multicenter, observational prospective, and retrospective study of patients admitted due to ARDS related to COVID-19 infection in Spain. Patients were grouped according to a clustering mixed-type data algorithm (k-prototypes) using continuous and categorical readily available variables at baseline and day 3.Results Of 6205 patients, 3743 (60%) were included in the study. According to silhouette analysis, patients were grouped in two clusters. At baseline, 1402 (37%) patients were included in cluster 1 and 2341(63%) in cluster 2. On day 3, 1557(42%) patients were included in cluster 1 and 2086 (57%) in cluster 2. The patients included in cluster 2 were older and more frequently hypertensive and had a higher prevalence of shock, organ dysfunction, inflammatory biomarkers, and worst respiratory indexes at both time points. The 90-day mortality was higher in cluster 2 at both clustering processes (43.8% [n = 1025] versus 27.3% [n = 383] at baseline, and 49% [n = 1023] versus 20.6% [n = 321] on day 3). Four hundred and fifty-eight (33%) patients clustered in the first group were clustered in the second group on day 3. In contrast, 638 (27%) patients clustered in the second group were clustered in the first group on day 3.Conclusions During the first days, patients can be clustered into two groups and the process of clustering patients may change as they continue to evolve. This means that despite a vast majority of patients remaining in the same cluster, a minority reaching 33% of patients analyzed may be re-categorized into different clusters based on their progress. Such changes can significantly impact their prognosis

    The evolution of the ventilatory ratio is a prognostic factor in mechanically ventilated COVID-19 ARDS patients

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    Background: Mortality due to COVID-19 is high, especially in patients requiring mechanical ventilation. The purpose of the study is to investigate associations between mortality and variables measured during the first three days of mechanical ventilation in patients with COVID-19 intubated at ICU admission. Methods: Multicenter, observational, cohort study includes consecutive patients with COVID-19 admitted to 44 Spanish ICUs between February 25 and July 31, 2020, who required intubation at ICU admission and mechanical ventilation for more than three days. We collected demographic and clinical data prior to admission; information about clinical evolution at days 1 and 3 of mechanical ventilation; and outcomes. Results: Of the 2,095 patients with COVID-19 admitted to the ICU, 1,118 (53.3%) were intubated at day 1 and remained under mechanical ventilation at day three. From days 1 to 3, PaO2/FiO2 increased from 115.6 [80.0-171.2] to 180.0 [135.4-227.9] mmHg and the ventilatory ratio from 1.73 [1.33-2.25] to 1.96 [1.61-2.40]. In-hospital mortality was 38.7%. A higher increase between ICU admission and day 3 in the ventilatory ratio (OR 1.04 [CI 1.01-1.07], p = 0.030) and creatinine levels (OR 1.05 [CI 1.01-1.09], p = 0.005) and a lower increase in platelet counts (OR 0.96 [CI 0.93-1.00], p = 0.037) were independently associated with a higher risk of death. No association between mortality and the PaO2/FiO2 variation was observed (OR 0.99 [CI 0.95 to 1.02], p = 0.47). Conclusions: Higher ventilatory ratio and its increase at day 3 is associated with mortality in patients with COVID-19 receiving mechanical ventilation at ICU admission. No association was found in the PaO2/FiO2 variation

    Global urban environmental change drives adaptation in white clover

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    Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale

    Heterogeneous contributions of change in population distribution of body mass index to change in obesity and underweight NCD Risk Factor Collaboration (NCD-RisC)

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    From 1985 to 2016, the prevalence of underweight decreased, and that of obesity and severe obesity increased, in most regions, with significant variation in the magnitude of these changes across regions. We investigated how much change in mean body mass index (BMI) explains changes in the prevalence of underweight, obesity, and severe obesity in different regions using data from 2896 population-based studies with 187 million participants. Changes in the prevalence of underweight and total obesity, and to a lesser extent severe obesity, are largely driven by shifts in the distribution of BMI, with smaller contributions from changes in the shape of the distribution. In East and Southeast Asia and sub-Saharan Africa, the underweight tail of the BMI distribution was left behind as the distribution shifted. There is a need for policies that address all forms of malnutrition by making healthy foods accessible and affordable, while restricting unhealthy foods through fiscal and regulatory restrictions

    Etiquetado de alimentos en Ecuador: implementación, resultados y acciones pendientes

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    RESUMEN Las enfermedades no transmisibles representan la principal causa de muerte en el mundo entero, siendo responsables de 38 millones de las defunciones registradas en 2012. Esta epidemia se asocia, principalmente, al tabaquismo, al consumo excesivo de alcohol, el sedentarismo y cambios en el patrón alimentario, caracterizado por el consumo de dietas con un elevado contenido de azúcar y grasas saturadas, propio de los alimentos procesados y bebidas azucaradas, sumado a una escasa ingesta de frutas y hortalizas. El Ecuador no escapa a ese perfil epidemiológico ni a los cambios en el patrón de consumo de alimentos, por lo cual, el Estado Ecuatoriano diseñó e implementó un plan de acción orientado a modificar el entorno obesogénico, que contempla seis líneas estratégicas, una de las cuales es la implementación de un sistema de etiquetado nutricional tipo semáforo a los alimentos procesados, a finales de 2014, orientado a garantizar el derecho de las personas a la información oportuna, clara, precisa y no engañosa sobre el contenido y características de estos alimentos. El presente artículo analiza el proceso de implementación del etiquetado de alimentos procesados, los resultados alcanzados hasta la fecha y propone medidas complementarias que se requieren para el logro de la meta prevista en el Plan Nacional del Buen Vivir, a la luz de la nueva evidencia científica y los distintos acuerdos y marcos regulatorios disponibles en nuestra Región. La metodología de estudio incluyó revisión bibliográfica y de actas, entrevistas a informantes clave, y análisis y procesamiento de fuentes secundarias
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