188 research outputs found
Estudio sobre sicodinamia familiar
El presente estudio es un intento de obtener un conocimiento científico de la sicodinamia de las familias de la clase baja urbana, así como de los problemas emocionales y los conflictos en las relaciones interpersonales, que pueden o no condicionar patología, en los individuos y en el grupo familiar, sin olvidar la influencia ambiental socio-cultural que los modula
Predicting Earthquake-Induced Landslides by Using a Stochastic Modeling Approach: A Case Study of the 2001 El Salvador Coseismic Landslides
In January and February 2001, El Salvador was hit by two strong earthquakes that triggered
thousands of landslides, causing 1259 fatalities and extensive damage. The analysis of aerial and
SPOT-4 satellite images allowed us to map 6491 coseismic landslides, mainly debris slides and
flows that occurred in volcanic epiclastites and pyroclastites. Four different multivariate adaptive
regression splines (MARS) models were produced using different predictors and landslide inventories
which contain slope failures triggered by an extreme rainfall event in 2009 and those induced by the
earthquakes of 2001. In a predictive analysis, three validation scenarios were employed: the first and
the second included 25% and 95% of the landslides, respectively, while the third was based on a k-fold
spatial cross-validation. The results of our analysis revealed that: (i) the MARS algorithm provides
reliable predictions of coseismic landslides; (ii) a better ability to predict coseismic slope failures was
observed when including susceptibility to rainfall-triggered landslides as an independent variable;
(iii) the best accuracy is achieved by models trained with both preparatory and trigger variables;
(iv) an incomplete inventory of coseismic slope failures built just after the earthquake event can be
used to identify potential locations of yet unreported landslides
Copper: Synthesis Techniques in Nanoscale and Powerful Application as an Antimicrobial Agent
Nanosized metal particles show specific physical and chemical properties that allow the creation of new composites materials, which are important for multiple applications in biology and medicine such as infections control. Metal nanoparticles, mainly copper, exhibit excellent inhibitory effect on Gram-positive and Gram-negative bacteria; therefore the exploration about the efficient, economical, and friendly environmental technics to synthesize inorganic nanoparticles is imperative. In this work a brief overview of the several methods is made including the comparison of the methods, mainly between sonochemical, microwave, and chemical routes. It allows determining the optimal parameters and technical conditions to synthesize copper nanoparticles with physical and chemical properties suitable for the oral bacterial inhibition
Plasma endocannabinoid levels in lean, overweight, and obese humans: relationships to intestinal permeability markers, inflammation, and incretin secretion
First published February 13, 2018Intestinal production of endocannabinoid and oleoylethanolamide (OEA) is impaired in high-fat diet/obese rodents, leading to reduced satiety. Such diets also alter the intestinal microbiome in association with enhanced intestinal permeability and inflammation, however little is known of these effects in humans. This study aimed to: (i) evaluate effects of lipid on plasma anandamide (AEA), 2-arachidonyl-sn-glycerol (2-AG) and OEA in humans, and (ii) examine relationships with intestinal permeability, inflammation markers and incretin hormone secretion.20 lean, 18 overweight and 19 obese participants underwent intraduodenal Intralipid® infusion (2 kcal/min) with collection of endoscopic duodenal biopsies and blood. Plasma AEA, 2-AG, and OEA (HPLC/tandem mass spectrometry), tumour necrosis factor-α (TNF-α), glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic peptide (GIP) (multiplex), and duodenal expression of occludin, zona-occludin-1 (ZO-1), intestinal-alkaline-phosphatase (IAP), and toll-like receptor-4 (TLR4) (RT-PCR), were assessed.Fasting plasma AEA was increased in obese, compared with lean and overweight (P<0.05), with no effect of BMI group or ID lipid infusion on plasma 2-AG or OEA. Duodenal expression of IAP and ZO-1 was reduced in obese, compared with lean (P<0.05), and these levels related negatively to plasma AEA (P<0.05). The iAUC for AEA was positively related to iAUC GIP (r=0.384, P=0.005).Obese individuals have increased plasma AEA and decreased duodenal expression of ZO-1 and IAP, in comparison to lean and overweight. The relationships between plasma AEA with duodenal ZO-1 and IAP, and GIP, suggest that altered endocannabinoid signalling may contribute to changes in intestinal permeability, inflammation and incretin release in human obesity.Tanya J. Little, Nada Cvijanovic, Nicholas V. DiPatrizio, Donovan A. Argueta, Christopher K. Rayner, X Christine Feinle-Bisset, and Richard L. Youn
Diversidad morfológica y fisiológica de cepas nativas de Trichoderma spp. en suelos cacaoteros de México
Objective: To study the morphological, microscopic and physiological diversity of native species of Trichoderma genus associated with soils with cocoa cultivation in Mexico.
Design / methodology / approximation: Colonies of Trichoderma spp. were isolated and characterized morphologically, microscopically and physiologically. from soil samples from six sites with different agronomic management: Organic Management, Conventional and No Management. A multivariate analysis (Analysis of main components and Analysis of hierarchical conglomerates) was carried out based on eight morphological characters of the colonies: shape, mycelium texture, obverse color, reverse color, central halo, number of concentric rings, type of sporulation and sporulation capacity; three microscopic characters: conidia shape and length / width relation of conidia and phialides.
Results: 30 strains with macroscopic characteristics of the genus Trichoderma were isolated and purified. The Principal Components Analysis showed that the first three components expressed 66.27% of the total variability in the 30 strains of Trichoderma spp., observing a wide distribution of the strains from the analysis of the evaluated characters. The analysis of hierarchical clusters determined eight groups divided into subgroups from the semiparcial correlation coefficient of 0.05.
Limitations of the study / implications: Trichoderma species show intraspecific variation that change with respect to the environmental conditions of the environment where they grow.
Findings / conclusions: The morphological, microscopic and physiological characterization shows a high variability expressed in different characters that demonstrate the high diversity and specificity of Trichoderma spp. in soils with cocoa cultivation in Mexico.Objetivo: Estudiar la diversidad morfológica, microscópica y fisiológica de especies nativas del género Trichoderma asociadas a suelos cacaoteros de México.
Diseño/metodología/aproximación: Se aislaron y caracterizaron morfológica, microscópica y fisiológicamente, colonias de Trichoderma spp. a partir de muestras de suelo de seis sitios con diferente manejo agronómico: Manejo Orgánico, Convencional y Sin Manejo. Se realizó un análisis multivariado (Análisis de componentes principales y Análisis de conglomerados jerárquicos) a partir de ocho caracteres morfológicos de las colonias: forma, textura del micelio, color anverso, color reverso, halo central, número de anillos concéntricos, tipo de esporulación y capacidad de esporulación; tres caracteres microscópicos: forma de conidios y relación largo/ancho de conidios y fiálides.
Resultados: Se aislaron y purificaron 30 cepas con características macroscópicas del género Trichoderma. El Análisis de Componentes Principales mostró que los primeros tres componentes expresaron el 66.27 % de la variabilidad total en las 30 cepas de Trichoderma spp., observando una amplia distribución de las cepas a partir del análisis de los caracteres evaluados. El análisis de conglomerados jerarquicos determinó ocho grupos divididos en subgrupos a partir del coeficiente de correlación semiparcial de 0.05.
Limitaciones del estudio/implicaciones: Las especies de Trichoderma muestran variación intraespecífica que cambian con respecto a las condiciones ambientales del medio donde crecen.
Hallazgos/conclusiones: La caracterización morfológica, microscópica y fisiológica, muestra una alta variabilidad expresada en diferentes caracteres que demuestran la alta diversidad y especificidad de las especies de Trichoderma spp. en suelos cacaoteros de México
Eficiencia del uso de nitrógeno en sorgo sensible al fotoperíodo en asocio con maíz en El Salvador
Eficiencia del uso de nitrógeno en sorgo sensible al fotoperíodo en asocio con maíz en El Salvador. En El Salvador se llevó a cabo un estudio durante los años 2001 y 2002 en Izalco y Santa Cruz Porrillo, con las variedades de sorgo: 86-EO-226, 85-SCP-805, ES-790, Santa Cruz, Limay y Yalaguina bajo 0, 47, 95 y 142 kg de N/ha. El rendimiento del grano y del rastrojo, la concentración y la extracción de nitrógeno (N), y el uso eficiente del N en el grano y en la biomasa (UEN) fueron determinados. Las variedades 85- SCP-805, ES-790 y 86-EO-226 produjeron de 1,8 a 2,9 t/ha más grano que las variedades Santa Cruz y Yalaguina, con poca diferencia en el rendimiento del rastrojo. La aplicación de N aumentó el rendimiento cuadráticamente, se obtuvo más del 67% del aumento cuando la aplicación de N fue de 47 kg de N/ha. El UEN del grano disminuyó con el aumento de N, pero en general las variedades 85-SCP-805, ES-790 y 86-E0- 226 dieron un UEN del grano mayor a 50 kg de materia seca del grano/kg de N extraído, mientras que Santa Cruz y Yalaguina mostraron UEN entre 20 y 30 kg de materia seca del grano/kg N extraido. Estos resultados indicaron que pueden aumentar el rendimiento del grano y del rastrojo, y el UEN del grano, en las variedades sensibles al fotoperíodo
A Systematic Review of Mosquito Coils and Passive Emanators: Defining Recommendations for Spatial Repellency Testing Methodologies.
Mosquito coils, vaporizer mats and emanators confer protection against mosquito bites through the spatial action of emanated vapor or airborne pyrethroid particles. These products dominate the pest control market; therefore, it is vital to characterize mosquito responses elicited by the chemical actives and their potential for disease prevention. The aim of this review was to determine effects of mosquito coils and emanators on mosquito responses that reduce human-vector contact and to propose scientific consensus on terminologies and methodologies used for evaluation of product formats that could contain spatial chemical actives, including indoor residual spraying (IRS), long lasting insecticide treated nets (LLINs) and insecticide treated materials (ITMs). PubMed, (National Centre for Biotechnology Information (NCBI), U.S. National Library of Medicine, NIH), MEDLINE, LILAC, Cochrane library, IBECS and Armed Forces Pest Management Board Literature Retrieval System search engines were used to identify studies of pyrethroid based coils and emanators with key-words "Mosquito coils" "Mosquito emanators" and "Spatial repellents". It was concluded that there is need to improve statistical reporting of studies, and reach consensus in the methodologies and terminologies used through standardized testing guidelines. Despite differing evaluation methodologies, data showed that coils and emanators induce mortality, deterrence, repellency as well as reduce the ability of mosquitoes to feed on humans. Available data on efficacy outdoors, dose-response relationships and effective distance of coils and emanators is inadequate for developing a target product profile (TPP), which will be required for such chemicals before optimized implementation can occur for maximum benefits in disease control
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Host- and Helminth-Derived Endocannabinoids That Have Effects on Host Immunity Are Generated during Infection.
Helminths have coevolved with their hosts, resulting in the development of specialized host immune mechanisms and parasite-specific regulatory products. Identification of new pathways that regulate helminth infection could provide a better understanding of host-helminth interaction and may identify new therapeutic targets for helminth infection. Here we identify the endocannabinoid system as a new mechanism that influences host immunity to helminths. Endocannabinoids are lipid-derived signaling molecules that control important physiologic processes, such as feeding behavior and metabolism. Following murine infection with Nippostrongylus brasiliensis, an intestinal nematode with a life cycle similar to that of hookworms, we observed increased levels of endocannabinoids (2-arachidonoylglycerol [2-AG] or anandamide [AEA]) and the endocannabinoid-like molecule oleoylethanolamine (OEA) in infected lung and intestine. To investigate endocannabinoid function in helminth infection, we employed pharmacological inhibitors of cannabinoid subtype receptors 1 and 2 (CB1R and CB2R). Compared to findings for vehicle-treated mice, inhibition of CB1R but not CB2R resulted in increased N. brasiliensis worm burden and egg output, associated with significantly decreased expression of the T helper type 2 cytokine interleukin 5 (IL-5) in intestinal tissue and splenocyte cultures. Strikingly, bioinformatic analysis of genomic and transcriptome sequencing (RNA-seq) data sets identified putative genes encoding endocannabinoid biosynthetic and degradative enzymes in many parasitic nematodes. To test the novel hypothesis that helminth parasites produce their own endocannabinoids, we measured endocannabinoid levels in N. brasiliensis by mass spectrometry and quantitative PCR and found that N. brasiliensis parasites produced endocannabinoids, especially at the infectious larval stage. To our knowledge, this is the first report of helminth- and host-derived endocannabinoids that promote host immune responses and reduce parasite burden
Historia de la agroecología en México
A mediados del siglo pasado, existían dos tipos de científicos de la agronomía en México. Unos, que veían una agricultura atrasada y que había, ciegamente, que llevar hacia los avances tec- nológicos más modernos. Otros, que salían al campo y exploraban intensivamente los sistemas indígenas y campesinos. El estudiar y dar a conocer la riqueza tanto biológica como humana que albergaban estos sistemas, dio pie a la agroecología en este país. Sobra decir que varios de los pioneros de esa ciencia a nivel mundial, fueron aprendices de sistemas indígenas mexicanos. En este trabajo se hace el esfuerzo por narrar los hitos históricos más importantes en la investigación y la enseñanza de la agroecología en el pasado y en la actualidad; además, hacemos también una reflexión sobre los desafíos que enfrenta esa disciplina
Immunoglobulin, glucocorticoid, or combination therapy for multisystem inflammatory syndrome in children: a propensity-weighted cohort study
Background: Multisystem inflammatory syndrome in children (MIS-C), a hyperinflammatory condition associated with SARS-CoV-2 infection, has emerged as a serious illness in children worldwide. Immunoglobulin or glucocorticoids, or both, are currently recommended treatments. Methods: The Best Available Treatment Study evaluated immunomodulatory treatments for MIS-C in an international observational cohort. Analysis of the first 614 patients was previously reported. In this propensity-weighted cohort study, clinical and outcome data from children with suspected or proven MIS-C were collected onto a web-based Research Electronic Data Capture database. After excluding neonates and incomplete or duplicate records, inverse probability weighting was used to compare primary treatments with intravenous immunoglobulin, intravenous immunoglobulin plus glucocorticoids, or glucocorticoids alone, using intravenous immunoglobulin as the reference treatment. Primary outcomes were a composite of inotropic or ventilator support from the second day after treatment initiation, or death, and time to improvement on an ordinal clinical severity scale. Secondary outcomes included treatment escalation, clinical deterioration, fever, and coronary artery aneurysm occurrence and resolution. This study is registered with the ISRCTN registry, ISRCTN69546370. Findings: We enrolled 2101 children (aged 0 months to 19 years) with clinically diagnosed MIS-C from 39 countries between June 14, 2020, and April 25, 2022, and, following exclusions, 2009 patients were included for analysis (median age 8·0 years [IQR 4·2–11·4], 1191 [59·3%] male and 818 [40·7%] female, and 825 [41·1%] White). 680 (33·8%) patients received primary treatment with intravenous immunoglobulin, 698 (34·7%) with intravenous immunoglobulin plus glucocorticoids, 487 (24·2%) with glucocorticoids alone; 59 (2·9%) patients received other combinations, including biologicals, and 85 (4·2%) patients received no immunomodulators. There were no significant differences between treatments for primary outcomes for the 1586 patients with complete baseline and outcome data that were considered for primary analysis. Adjusted odds ratios for ventilation, inotropic support, or death were 1·09 (95% CI 0·75–1·58; corrected p value=1·00) for intravenous immunoglobulin plus glucocorticoids and 0·93 (0·58–1·47; corrected p value=1·00) for glucocorticoids alone, versus intravenous immunoglobulin alone. Adjusted average hazard ratios for time to improvement were 1·04 (95% CI 0·91–1·20; corrected p value=1·00) for intravenous immunoglobulin plus glucocorticoids, and 0·84 (0·70–1·00; corrected p value=0·22) for glucocorticoids alone, versus intravenous immunoglobulin alone. Treatment escalation was less frequent for intravenous immunoglobulin plus glucocorticoids (OR 0·15 [95% CI 0·11–0·20]; p<0·0001) and glucocorticoids alone (0·68 [0·50–0·93]; p=0·014) versus intravenous immunoglobulin alone. Persistent fever (from day 2 onward) was less common with intravenous immunoglobulin plus glucocorticoids compared with either intravenous immunoglobulin alone (OR 0·50 [95% CI 0·38–0·67]; p<0·0001) or glucocorticoids alone (0·63 [0·45–0·88]; p=0·0058). Coronary artery aneurysm occurrence and resolution did not differ significantly between treatment groups. Interpretation: Recovery rates, including occurrence and resolution of coronary artery aneurysms, were similar for primary treatment with intravenous immunoglobulin when compared to glucocorticoids or intravenous immunoglobulin plus glucocorticoids. Initial treatment with glucocorticoids appears to be a safe alternative to immunoglobulin or combined therapy, and might be advantageous in view of the cost and limited availability of intravenous immunoglobulin in many countries. Funding: Imperial College London, the European Union's Horizon 2020, Wellcome Trust, the Medical Research Foundation, UK National Institute for Health and Care Research, and National Institutes of Health
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