333 research outputs found

    Synthesis of a novel thiolated photopolymerizable monomer derived from soybean oil and its thiol-ene photopolymerization with unsaturated monomers

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    In this study is presented a synthetic methodology to prepare a thiolated monomer derived from renewable natural products resources such as the soybean oil. This product was thiolated by a thiol-ene coupling reaction between the double bonds of the vegetable oil and thioacetic acid. The obtained intermediate was subsequently hydrolyzed to obtain a mixture of thiolated fatty methyl esters. The attained mixture was characterized by FTIR and NMR spectroscopies. The reactivity of this compound was tested as comonomer in a thiol-ene photopolymerization using different types of unsaturated compounds. It was found that the thiolated compound reacted readily under UV irradiation forming polythioethers. The nature of the obtained polymers depended on the characteristics of the unsaturated monomers

    Levantamiento Detallado de los Suelos de la Granja Experimental del Sena corregimiento de gaira (Santa Marta, Magdalena. Colombia)

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    El trabajo se realizó en la Granja Experimental del Sena, Seccional: Gaira, jurisdicción del municipio de Santa Marta, departamento del Magdalena. Esta se encuentra ubicada astronómicamente entre los 74°-07' y 74° -12' de longitud Oeste y entre los 11°- 11' y 11°- 15' de latitud Norte. La zona recorrida tiene una extensión de 130 Ha. aún cuando sólo se trabajó en 110 Ha. Se encuentra a 4 m.s.n.m y se da en ella una temperatura media anual de 27.3°C y. una precipitación media anual de 557.8 mm. El levantamiento detallado que aquí se presenta, tiene por objeto mostrar en una forma lo más exacta posible, el potencial producido de la zona para una mejor utilización de sus suelos. La principal vía de comunicación que posee, es un carretero que se desprende de la carretera Troncal del Caribe, la cual le permite la comunicación con la ciudad de Santa Marta, capital del departamento del Magdalena, Ciénaga y Barranquilla. También pasa la línea de los ferrocarriles nacionales del Atlántico. La topografía dominante es plana, exceptuando la parte que presenta elevaciones. La principal fuente hidrográfica la constituye el río Gaira que pasa por la parte sur. En general, los suelos de ésta zona son de origen aluvial como se puede comprobar en las calicatas realizadas en la serie Mosquito y en la serie Sena, con drenaje interno y externo de bueno a rápido. Los análisis químicos nos revelaron que éstos suelos son bajos en materia orgánica y fósforo, pero altos en potasio, no presentan problemas con salinidad, pero el calcio y el magnesio son moderadamente altos. La erosión es prácticamente nula. Se puede decir que la población se circunscribe a la explotación mixta del área. (Agricultura y Ganadería). Es necesario aclarar que la granja se encuentra dedicada a impartir en ella, educación a nivel medio y técnico en el campo agropecuario

    Self-Healing Photocurable Epoxy/thiol-ene Systems Using an Aromatic Epoxy Resin

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    A rapid and efficient method to obtain self-healing epoxy resins is discussed. This method is based on the use of a thiol-disulfide oligomer obtained by partial oxidation of a multifunctional thiol using a hypervalent iodine (III) compound as oxidant. The oligomer was characterized by Fourier transform infrared spectroscopy (FTIR), Raman and nuclear magnetic resonance spectroscopies, and gel permeation chromatography (GPC). The oligomer was a joint component of the thiol-ene system along with a tetra-allyl-functionalized curing agent. The kinetics of the photopolymerization of diglycidylether of bisphenol A (DGEBA) revealed that conversions of the epoxy groups as high as 80% were achieved in only 15 minutes by increasing the concentration of the thiol-ene system in the formulation. The disulfide bonds introduced in the copolymer using the thiol-disulfide oligomer allowed the repairing of the test specimens in as little as 10 minutes when the specimens were heated at 80°C or for 500 minutes at room temperature. The analysis of the mechanical properties using dynamic mechanical analysis (DMA) showed that the specimens displayed a healing efficiency up to 111% compared with the unhealed specimens, depending on the amount of polythioethers present in the copolymer

    Prescription for COVID-19 by non-medical professionals during the pandemic in Colombia: a cross-sectional study

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    Antecedentes: La pandemia de COVID-19 ha llevado a un aumento en el comportamiento de la automedicación (SM). Dada la liberación masiva de información engañosa durante la pandemia, algunas farmacias recomiendan medicamentos como la ivermectina, la azitromicina, la hidroxicloroquina, entre otros, que no son útiles para prevenir o tratar la COVID-19 y podrían exponer a los pacientes a efectos secundarios innecesarios e interacciones con otros medicamentos. La gente debe estar al tanto de los usos aprobados y no aprobados, y de los posibles efectos secundarios de estos medicamentos. Justificación: El objetivo de este estudio era conocer los medicamentos, incluidos los productos naturales y los medicamentos homeopáticos, ofrecidos por los establecimientos farmacéuticos colombianos para la prevención y el tratamiento de la COVID-19, así como la información proporcionada sobre el uso seguro del producto. Métodos: El estudio se realizó utilizando el método de compras misteriosas, recopilando datos a través de llamadas telefónicas a cada uno de los establecimientos por parte de una persona capacitada que fingía ser un paciente con síntomas de COVID-19. El estudio incluyó 482 establecimientos farmacéuticos de 16 departamentos colombianos. Resultados: De los 59 medicamentos sugeridos por las farmacias, los más recomendados fueron azitromicina, ivermectina, acetaminofén, ibuprofeno y aspirina. La dosis recomendada se indicó en el 85,5% (236) de los establecimientos farmacéuticos, y el 14,5% (40) de ellos reportó los efectos adversos más comunes del producto recomendado. Alrededor del 9,4 % (26) de los establecimientos informaron de posibles interacciones de los medicamentos y sustancias recomendados con alimentos, bebidas o suplementos. Conclusión: La mayoría de los establecimientos farmacéuticos incluidos en el estudio promovieron una automedicación inadecuada para la COVID-19 en Colombia durante la pandemia.Background: The COVID-19 pandemic has led to an increase in the behavior of self-medication (SM). Given the massive release of misleading information during the pandemic, some pharmacies recommend drugs such as ivermectin, azithromycin, hydroxychloroquine among others, which are not useful for preventing or treating COVID-19 and could expose patients to unnecessary side effects and interactions with other medications. People should be aware of the approved and non-approved uses, and potential side effects of these drugs. Rationale: The aim of this study was to know the drugs, including natural products and homeopathic drugs, offered by Colombian pharmaceutical establishments for the prevention and treatment of COVID-19, as well as the information provided on the safe use of the product. Methods: The study was done using the mystery shopping method, collecting data through telephone calls to each of the establishments by a trained individual pretending to be a patient with COVID-19 symptoms. The study included 482 pharmaceutical establishments from 16 Colombian departments. Results: Of 59 drugs suggested by pharmacies, the most recommended were azithromycin, ivermectin, acetaminophen, ibuprofen, and aspirin. The recommended dose was indicated in 85.5% (236) of the pharmaceutical establishments, and 14.5% (40) of them reported the most common adverse effects of the recommended product. About 9.4% (26) of the establishments reported possible interactions of the recommended drugs and substances with food, beverages, or supplements. Conclusion: The majority of the pharmaceutical establishments included in the study promoted inadequate self-medication for COVID-19 in Colombia during the pandemic.https://scienti.minciencias.gov.co/cvlac/visualizador/generarCurriculoCv.do?cod_rh=0001402116https://scholar.google.com/citations?hl=es&user=OW0mejcAAAAJ&view_op=list_works&sortby=pubdatehttps://scienti.minciencias.gov.co/gruplac/jsp/visualiza/visualizagr.jsp?nro=00000000004151https://orcid.org/0000-0002-4835-9739Introducción, Materiales y Métodos, Resultados, Conclusiones, Bibliografía

    Proyecto de emprendimiento social Reciclaje Comunitario

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    La cultura del reciclaje hoy día se ha convertido en un compromiso social de la humanidad, hace unos años parecía una cuestión de moda o para algunas empresas servía como estrategia para mejorar su imagen y destacarse de la competencia, por fortuna esa ideología tomo conciencia a partir de las catástrofes naturales con las que la tierra ha querido reclamar sus derechos, en razón a esto proporcionamos a nuestro proyecto social, todo la complejidad requerida para hacerlo lo más viable posible, evaluando desde todas las perspectivas sociales que pudiesen apoyar esta iniciativa, claro está, acompañado de un componente social adicional, el cual se adjudica a la recuperación de una determinada comunidad en condición de vulnerabilidad, quienes en su pasado reciente actuaban en detrimento social con acciones delincuenciales, pero que en la actualidad brindan un aporte significativo al planeta, ya que al estar vinculados a nuestro proyecto de reciclaje su perspectiva ante la vida y la sociedad dio un giro trascendental. Con el fin de esculpir nuestro proyecto utilizamos herramientas tecnológicas que nos permitieron acertar en la toma de decisiones, luego de planificar una serie de tareas y actividades claves para lograr atracción de todos los entornos en que se desarrolla el proyecto, salir al mercado sin tener una estrategia o un plan de negocio definidos, solo basados en la persuasión, ensayo y error solo traería fracaso en el proyecto, desperdiciando los recursos invertidos en el mismo, hay que emplear todas aquellas herramientas que minimicen las probabilidades del fracaso y el método Canvas es una de ellas ya que nos permite hacer pruebas sobre el papel de nuestra idea de negocio. Todas las actividades propuestas en nuestro modelo de negocio deben tener coherencia con la propuesta de valor, integrar a toda la comunidad en general, pues todos sin discriminación resultan ser nuestros clientes potenciales, ya que necesitamos una comunidad consiente y amigable con el medio ambiente, de igual forma nuestros aliados estratégicos, los cuales fortalecerán, re potencializando los procesos diseñados para el proyecto. Basados en una estructura organizacional fortalecida y proyecto sostenible y sustentable, se nos facilitara lograr la atención rápidamente de posibles inversionistas hacia el proyecto, iniciativa que pretende, además repercutir en todas las comunidades vulnerables, para que vean en e l reciclaje una gran oportunidad de negocio.The culture of recycling today has become a social commitment of humanity, a few years ago it seemed a matter of fashion or for some companies served as a strategy to improve their image and stand out from the competition, fortunately that ideology became aware of the natural catastrophes with which the earth has wanted to claim its rights, because of this we provide our social project, all the complexity required to make it as viable as possible, evaluating from all social perspectives that could support this initiative, of course , accompanied by an additional social component, which is awarded to the recovery of a certain community in vulnerable condition, who in their recent past acted in social detriment with criminal actions, but which currently provide a significant contribution to the planet, that being linked to our recycling project your perspective on life and society took a transcendental turn. In order to sculpt our project we use technological tools that allowed us to make the right decisions, after planning a series of tasks and key activities to attract all the environments in which the project is developed, go out to the market without having a strategy or a defined business plan, only based on persuasion, trial and error would only bring failure in the project, wasting the resources invested in it, we must use all those tools that minimize the chances of failure and the Canvas method is a of them since it allows us to test the role of our business idea. All the activities proposed in our business model must be coherent with the value proposal, integrate the whole community in general, because all without discrimination turn out to be our potential clients, since we need a conscientious and friendly community with the environment, Equally, our strategic allies will strengthen, strengthening the processes designed for the project. Based on a strengthened organizational structure and a sustainable and sustainable project, we will be able to quickly get the attention of potential investors to the project, an initiative that aims to also affect all vulnerable communities, so that they see recycling as a great business opportunity

    BAFF Mediates Splenic B Cell Response and Antibody Production in Experimental Chagas Disease

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    Chagas disease, caused by the protozoan Trypanosoma cruzi, is endemic in Central and South America. It affects 20 million people and about 100 million people are at risk of infection in endemic areas. Some cases have been identified in non-endemic countries as a consequence of blood transfusion and organ transplantation. Chagas disease presents three stages of infection. The acute phase appears one to two weeks after infection and includes fever, swelling around the bite site, enlarged lymph glands and spleen, and fatigue. This stage is characterized by circulating parasites and many immunological disturbances including a massive B cell response. In general, the acute episode self-resolves in about 2 months and is followed by a clinically silent indeterminate phase characterized by absence of circulating parasites. In about one-third of the cases, the indeterminate phase evolves into a chronic phase with clinically defined cardiac or digestive disturbances. Current knowledge suggests that the persistence of parasites coupled with an unbalanced immune response sustain inflammatory response in the chronic stage. We believe that an effective treatment for chronic Chagas disease should combine antiparasitic drugs with immunomodulators aimed at reducing inflammation and autoreactive response. Our findings enlighten a new role of BAFF-BAFF-R signaling in parasite infection that partially controls polyclonal B cell response but not parasitespecific class-switched primary effectors B cells

    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

    Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

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    The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality

    Atrasentan and renal events in patients with type 2 diabetes and chronic kidney disease (SONAR): a double-blind, randomised, placebo-controlled trial

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    Background: Short-term treatment for people with type 2 diabetes using a low dose of the selective endothelin A receptor antagonist atrasentan reduces albuminuria without causing significant sodium retention. We report the long-term effects of treatment with atrasentan on major renal outcomes. Methods: We did this double-blind, randomised, placebo-controlled trial at 689 sites in 41 countries. We enrolled adults aged 18–85 years with type 2 diabetes, estimated glomerular filtration rate (eGFR)25–75 mL/min per 1·73 m 2 of body surface area, and a urine albumin-to-creatinine ratio (UACR)of 300–5000 mg/g who had received maximum labelled or tolerated renin–angiotensin system inhibition for at least 4 weeks. Participants were given atrasentan 0·75 mg orally daily during an enrichment period before random group assignment. Those with a UACR decrease of at least 30% with no substantial fluid retention during the enrichment period (responders)were included in the double-blind treatment period. Responders were randomly assigned to receive either atrasentan 0·75 mg orally daily or placebo. All patients and investigators were masked to treatment assignment. The primary endpoint was a composite of doubling of serum creatinine (sustained for ≥30 days)or end-stage kidney disease (eGFR <15 mL/min per 1·73 m 2 sustained for ≥90 days, chronic dialysis for ≥90 days, kidney transplantation, or death from kidney failure)in the intention-to-treat population of all responders. Safety was assessed in all patients who received at least one dose of their assigned study treatment. The study is registered with ClinicalTrials.gov, number NCT01858532. Findings: Between May 17, 2013, and July 13, 2017, 11 087 patients were screened; 5117 entered the enrichment period, and 4711 completed the enrichment period. Of these, 2648 patients were responders and were randomly assigned to the atrasentan group (n=1325)or placebo group (n=1323). Median follow-up was 2·2 years (IQR 1·4–2·9). 79 (6·0%)of 1325 patients in the atrasentan group and 105 (7·9%)of 1323 in the placebo group had a primary composite renal endpoint event (hazard ratio [HR]0·65 [95% CI 0·49–0·88]; p=0·0047). Fluid retention and anaemia adverse events, which have been previously attributed to endothelin receptor antagonists, were more frequent in the atrasentan group than in the placebo group. Hospital admission for heart failure occurred in 47 (3·5%)of 1325 patients in the atrasentan group and 34 (2·6%)of 1323 patients in the placebo group (HR 1·33 [95% CI 0·85–2·07]; p=0·208). 58 (4·4%)patients in the atrasentan group and 52 (3·9%)in the placebo group died (HR 1·09 [95% CI 0·75–1·59]; p=0·65). Interpretation: Atrasentan reduced the risk of renal events in patients with diabetes and chronic kidney disease who were selected to optimise efficacy and safety. These data support a potential role for selective endothelin receptor antagonists in protecting renal function in patients with type 2 diabetes at high risk of developing end-stage kidney disease. Funding: AbbVie

    Canagliflozin and renal outcomes in type 2 diabetes and nephropathy

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    BACKGROUND Type 2 diabetes mellitus is the leading cause of kidney failure worldwide, but few effective long-term treatments are available. In cardiovascular trials of inhibitors of sodium–glucose cotransporter 2 (SGLT2), exploratory results have suggested that such drugs may improve renal outcomes in patients with type 2 diabetes. METHODS In this double-blind, randomized trial, we assigned patients with type 2 diabetes and albuminuric chronic kidney disease to receive canagliflozin, an oral SGLT2 inhibitor, at a dose of 100 mg daily or placebo. All the patients had an estimated glomerular filtration rate (GFR) of 30 to &lt;90 ml per minute per 1.73 m2 of body-surface area and albuminuria (ratio of albumin [mg] to creatinine [g], &gt;300 to 5000) and were treated with renin–angiotensin system blockade. The primary outcome was a composite of end-stage kidney disease (dialysis, transplantation, or a sustained estimated GFR of &lt;15 ml per minute per 1.73 m2), a doubling of the serum creatinine level, or death from renal or cardiovascular causes. Prespecified secondary outcomes were tested hierarchically. RESULTS The trial was stopped early after a planned interim analysis on the recommendation of the data and safety monitoring committee. At that time, 4401 patients had undergone randomization, with a median follow-up of 2.62 years. The relative risk of the primary outcome was 30% lower in the canagliflozin group than in the placebo group, with event rates of 43.2 and 61.2 per 1000 patient-years, respectively (hazard ratio, 0.70; 95% confidence interval [CI], 0.59 to 0.82; P=0.00001). The relative risk of the renal-specific composite of end-stage kidney disease, a doubling of the creatinine level, or death from renal causes was lower by 34% (hazard ratio, 0.66; 95% CI, 0.53 to 0.81; P&lt;0.001), and the relative risk of end-stage kidney disease was lower by 32% (hazard ratio, 0.68; 95% CI, 0.54 to 0.86; P=0.002). The canagliflozin group also had a lower risk of cardiovascular death, myocardial infarction, or stroke (hazard ratio, 0.80; 95% CI, 0.67 to 0.95; P=0.01) and hospitalization for heart failure (hazard ratio, 0.61; 95% CI, 0.47 to 0.80; P&lt;0.001). There were no significant differences in rates of amputation or fracture. CONCLUSIONS In patients with type 2 diabetes and kidney disease, the risk of kidney failure and cardiovascular events was lower in the canagliflozin group than in the placebo group at a median follow-up of 2.62 years
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