85 research outputs found

    Procedimiento para la purificación de ácido eicosapentaenoico (EPA)

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    Número de publicación: ES2292341 A1 (01.03.2008) También publicado como: ES2292341 B1 (16.03.2009) Número de Solicitud: Consulta de Expedientes OEPM (C.E.O.)P200600777 (13.03.2006)La presente invención se refiere a un procedimiento para la purificación de EPA mediante reacciones enzimáticas de esterificación, caracterizadas por lipasas, a partir de extractos de pescado y microalgas y al uso del factor adimensional de eficacia para la cuantificación de la eficacia de las lipasas para concentrar y recuperar de forma simultánea un ácido graso poliinsaturado en la fracción de ácidos grasos libres.Universidad de Almerí

    Obtención de ácido eicosapentaenoico de alta pureza a partir de la microalga Phaeodactylum tricornutum mediante un proceso de tres etapas

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    Número de publicación: ES2120898 A1 (01.11.1998) También publicado como: ES2120898 B1 (16.05.1999) Número de Solicitud: Consulta de Expedientes OEPM (C.E.O.) P9602090 (04.10.1996)El ácido eicosapentaenoico (EPA), de alto interés para la salud humana, ha sido obtenido de la microalga Phaeodactylum tricornutum mediante un proceso de tres etapas: extracción de los ácidos grasos por saponificación directa de la biomasa húmeda; concentración de los ácidos grasos poliinsaturados (PUFAs) por el método de la urea y purificación del EPA por cromatografía liquida de alta resolución (HPLC). La extracción de los ácidos grasos se ha llevado a cabo con koh-etanol (96% v/v) (1h, 60 c) extrayéndose el 90,9% del EPA presente en la biomasa. La relación urea/ácidos grasos ha sido 4:1 p/p, la temperatura de cristalización 28 c y se ha utilizado metanol como disolvente de la urea, obteniéndose un rendimiento del 78,6% en EPA. La purificación del EPA se ha realizado en una columna de 4,7 cm d.i. X 30 cm, fase inversa c18 y utilizando metanol-agua (1% ACH) 80:20 p:p como fase móvil; el 97,3% del EPA cargado en la columna se ha recuperado con una pureza del 95,8%. El rendimiento global del proceso es del 69,5%. La producción de EPA de alta pureza es de 2,46 g/día, determinada por la producción de biomasa de phaeodactylum tricornutum de un fotobiorreactor tubular externo (100 g/día). Este mismo proceso puede aplicarse a otras microalgas y a la obtención de otros PUFAsUniversidad de Almerí

    Production of triacylglycerols rich in palmitic acid at sn-2 position by lipase-catalyzed acidolysis

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    This paper studies the synthesis of triacylglycerols (TAGs) rich in palmitic acid (PA) at sn-2 position from palm stearin (PS), a vegetable oil highly rich in PA (60%, but only 12.8% of this is located at sn-2 position). These PA rich TAGs were obtained by lipase-catalyzed acidolysis of this oil with free fatty acids (FFAs) highly rich in PA, such as commercial PA (98% PA) and a FFA extract obtained by saponification of PS (60% PA). PA has a melting point of 63 ºC and during the acidolysis reaction the substrates, highly rich in this acid, must remain liquid; therefore high temperatures or solvents must be used. An important objective of this work was to operate without solvent and at the lowest possible temperature. In this acidolysis reaction four factors were firstly studied: type of lipase, temperature, solvent amount and the intensity of treatment (IOT = lipase amount × reaction time/PS amount). The influence of these variables was studied in a stirred tank reactor (STR). The lipases tested were Novozym 435 from Candida antarctica (immobilized on a macroporous acrylic resin), and lipases QLC (immobilized on diatomaceous earth), and QLM (non immobilized), both from Alcaligenes sp., and the one selected was lipase QLC. According to the manufacturer the optimum temperature for this lipase is 65-70 ºC, which allows it to operate without solvent. The best results with lipase QLC (TAGs with 80% PA, both total and at sn-2 position) were obtained with commercial PA, at 65 ºC, a 3:1 FFA/PS molar ratio (1:1 w/w), without solvent and an IOT = 7 g lipase × h/g PS (for example 2.5 g PS, 2.5 g commercial PA, 0.75 g lipase and 24 h). These results were the basis for establishing the operational conditions to obtain PA rich TAGs with the lipase immobilized in a packed bed reactor (PBR), operating by recirculation of the reaction mixture through the lipase bed. In this system TAGs with 75% PA were obtained at an IOT = 8 g lipase × h/g PS. This result and the apparent kinetic constants obtained in both reactors show that the reaction rate is lower in the PBR than in the STR. Subsequently, PA enriched TAGs were separated from FFAs by two procedures: the first one at room temperature and in presence of hexane and the second one at 65 ºC and without hexane. Using the first procedure, 95% of TAGs in the acidolysis reaction mixture were recovered with a purity of 99%. Using the second one, 98% pure TAGs were obtained with a recovery yield of 80%. Therefore, these highly rich PA TAGs can be obtained by acidolysis of PS and PA rich FFAs in solvent-free media, and then these TAGs also can be purified to 98% in absence of hexane, using only a hydroethanolic KOH solution.Ministerio de Educación y Ciencia, FEDER, Proyects AGL2003-03335, CTQ2007-6407

    Production of triacylglycerols rich in palmitic acid at position 2 as intermediates for the synthesis of human milk fat substitutes by enzymatic acidolysis

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    This paper studies the synthesis of triacylglycerols (TAGs) rich in palmitic acid (PA) at position 2, from palm oil stearin (POS), a vegetable oil highly rich in this acid (60%). The developed process consists of two steps: (1) obtaining PA enriched free fatty acids (FFAs), and (2) enrichment of POS in PA by acidolysis of this oil with PA enriched FFAs, catalyzed by lipase Novozym 435. In step (1) two PA enriched FFA mixtures were obtained: one by saponification of POS, and a PA concentrate (75.1% PA) obtained by crystallization at low temperature in solvents. The latter was obtained carrying out two crystallizations in acetone at -24 and -20 ºC, from which PA was recovered in the solid phases with a total yield of 84%. These PA enriched FFA mixtures were used in step (2) of acidolysis of POS, along with commercial PA (98% PA). In this acidolysis step four factors were studied: temperature, hexane/reaction mixture ratio, FFA/POS molar ratio and the intensity of treatment (IOT = lipase amount × reaction time/POS amount). The best results (TAGs with 79% PA and 75% PA at position 2) were obtained with commercial PA, at 37 ºC, 10 mL hexane/g reaction mixture, a FFA/POS molar ratio 3:1 (1:1 w/w) and an IOT = 9.6 g lipase × h/g POS (for example 48 h, 10 g lipase and 50 g POS). PA enriched TAGs were purified neutralizing the FFAs by KOH hydroethanolic solutions and extracting the TAGs with hexane. In this way 99% pure acylglycerols (TAG+DAG) were obtained; the recovery yield of this purification step was 95%. The experiments carried out with POS demonstrated that it is possible to use only this oil (60% PA, 23% PA at position 2) as a source of PA to obtain a TAG with 70.7% PA and 70.5% PA at position 2. This process consists of four steps: (1) saponification of POS, (2) crystallization of FFAs to obtain PA enriched FFAs (75.1% PA), (3) acidolysis of POS with these FFAs, catalyzed with Novozym 435, to produce PA enriched TAGs at position 2 (70.5% PA) and (4) purification of TAGs to obtain approximately 95% purity and yield. These PA enriched TAGs could be used to obtain structured TAGs rich in PA at position 2 and in oleic acid at positions 1 and 3 (OPO), which is the principal TAG of human milk fat.Ministerio de Educación y Ciencia (Spain), FEDER, Projects AGL2003-03335 and CTQ2007-64079

    Production of structured triacylglycerols by acidolysis catalyzed by lipases immobilized in a packed bed reactor

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    The aim of this work was to produce structured triacylglycerols (STAGs), with caprylic acid located at positions 1 and 3 of the glycerol backbone and docosohexaenoic acid (DHA) at position 2, by acidolysis of tuna oil and caprylic acid (CA) catalyzed by lipases Rd, from Rhizopus delemar, and Palatase 20000L from Mucor miehei immobilized on Accurel MP1000 in a packed bed reactor (PBR), working in continuous and recirculation modes. First, different lipase/support ratios were tested for the immobilization of lipases and the best results were obtained with ratios of 0.67 (w/w) for lipase Rd and 6.67 (w/w) for Palatase. Both lipases were stable for at least 4 days in the operational conditions. In the storage conditions (5 ºC) lipases Rd and Palatase maintained constant activity for 5 and 1 month, respectively. These catalysts have been used to obtain STAGs by acidolysis of tuna oil and CA in a PBR operating with recirculation of the reaction mixture through the lipase bed. Thus, STAGs with 52-53% CA and 14-15% DHA were obtained. These results were the basis for establishing the operational conditions to obtain STAGs operating in continuous mode. These new conditions were established maintaining constant intensity of treatment (IOT, lipase amount × reaction time/oil amount). In this way STAGs with 44-50% CA and 17-24% DHA were obtained operating in continuous mode. Although the compositions of STAGs obtained with both lipases were similar, Palatase required an IOT about 4 times higher than lipase Rd. To separate the acidolysis products (free fatty acids, FFAs, and STAGs) an extraction method of FFAs by water-ethanol solutions was tested. The following variables were optimized: water/ethanol ratio (the best results were attained with a water/ethanol ratio of 30:70 w/w), the solvent/FFA-STAG mixture ratio (3:1 w/w) and the number of extraction steps (3 to 5). In these conditions highly pure STAGs (93-96%) were obtained with a yield of 85%. The residual FFAs can be eliminated by neutralization with a hydroethanolic KOH solution to obtain pure STAGs. The positional analysis of these STAGs, carried out by alcoholysis catalyzed by lipase Novozym 435, has shown that CA represents 55% of fatty acids located at positions 1 and 3 and DHA represents 42% of fatty acids at position 2.Ministerio de Educación y Ciencia (Spain), FEDER, Projects AGL2003-03335 and CTQ2007-6407

    Production of biodiesel from vegetable oil and microalgae by fatty acid extraction and enzymatic esterification

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    The aim of this work was to obtain biodiesel (methyl esters) from the saponifiable lipids (SLs) fraction of the microalga Nannochloropsis gaditana, whose biomass dry weight contains 12.1 wt% of these lipids. SLs were extracted from the microalga as free fatty acids (FFAs) for subsequent transformation to methyl esters (biodiesel) by enzymatic esterification. Extraction as FFAs rather than as SLs allows them to be obtained with higher purity. Microalgal FFAs were obtained by direct saponification of lipids in the biomass and subsequent extraction-purification with hexane. Esterification of FFAs with methanol was catalysed by lipase Novozym 435 from Candida antarctica. Stability studies of this lipase in the operational conditions showed that the esterification degree (ED) attained with the same batch of lipase remained constant over six reaction cycles (36 h total reaction time). The optimal conditions attained for 4 g of FFAs were 25 ºC, 200 rpm, methanol/FFA molar ratio of 1.5:1, Novozym 435/FFA ratio of 0.025:1 w/w and 4 h reaction time. In these conditions the ED attained was 92.6%, producing a biodiesel with 83 wt% purity from microalgal FFAs. Several experimental scales were tested (from 4 to 40 g FFAs), and in all cases similar EDs were obtained

    Bienestar y familia, una mirada desde la psicología positiva

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    Este libro está dirigido a estudiantes y profesionales en psicología y áreas afines, como enfermería, trabajo social o educación, y a los interesados en personalidad positiva. Cada capítulo se presenta de manera sencilla y con una estructura didáctica, pero sin perder rigor científico y calidad de la revisión, con el fin de facilitar el acceso a la información sobre bienestar individual, familiar y social de una forma accesible para adentrarnos al estudio de temas de psicología positiva. Dadas las temáticas, se consideró pertinente dividir este libro en dos secciones: I. Psicología positiva y bienestar. II. Bienestar individual y familiar.Universidad Autónoma del Estado de México y Ediciones y Gráficos Eón, S.A. de C.V

    Mutational Landscape of CEBPA in Mexican Pediatric Acute Myeloid Leukemia Patients: Prognostic Implications

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    BackgroundIn Mexico, the incidence of acute myeloid leukemia (AML) has increased in the last few years. Mortality is higher than in developed countries, even though the same chemotherapy protocols are used. CCAAT Enhancer Binding Protein Alpha (CEBPA) mutations are recurrent in AML, influence prognosis, and help to define treatment strategies. CEBPA mutational profiles and their clinical implications have not been evaluated in Mexican pediatric AML patients.Aim of the StudyTo identify the mutational landscape of the CEBPA gene in pediatric patients with de novo AML and assess its influence on clinical features and overall survival (OS).Materials and MethodsDNA was extracted from bone marrow aspirates at diagnosis. Targeted massive parallel sequencing of CEBPA was performed in 80 patients.ResultsCEBPA was mutated in 12.5% (10/80) of patients. Frameshifts at the N-terminal region were the most common mutations 57.14% (8/14). CEBPA biallelic (CEBPABI) mutations were identified in five patients. M2 subtype was the most common in CEBPA positive patients (CEBPAPOS) (p = 0.009); 50% of the CEBPAPOS patients had a WBC count > 100,000 at diagnosis (p = 0.004). OS > 1 year was significantly better in CEBPA negative (CEBPANEG) patients (p = 0.0001). CEBPAPOS patients (either bi- or monoallelic) had a significantly lower OS (p = 0.002). Concurrent mutations in FLT3, CSF3R, and WT1 genes were found in CEBPAPOS individuals. Their contribution to poor OS cannot be ruled out.ConclusionCEBPA mutational profiles in Mexican pediatric AML patients and their clinical implications were evaluated for the first time. The frequency of CEBPAPOS was in the range reported for pediatric AML (4.5–15%). CEBPA mutations showed a negative impact on OS as opposed to the results of other studies

    Hyperoxemia and excess oxygen use in early acute respiratory distress syndrome : Insights from the LUNG SAFE study

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    Publisher Copyright: © 2020 The Author(s). Copyright: Copyright 2020 Elsevier B.V., All rights reserved.Background: Concerns exist regarding the prevalence and impact of unnecessary oxygen use in patients with acute respiratory distress syndrome (ARDS). We examined this issue in patients with ARDS enrolled in the Large observational study to UNderstand the Global impact of Severe Acute respiratory FailurE (LUNG SAFE) study. Methods: In this secondary analysis of the LUNG SAFE study, we wished to determine the prevalence and the outcomes associated with hyperoxemia on day 1, sustained hyperoxemia, and excessive oxygen use in patients with early ARDS. Patients who fulfilled criteria of ARDS on day 1 and day 2 of acute hypoxemic respiratory failure were categorized based on the presence of hyperoxemia (PaO2 > 100 mmHg) on day 1, sustained (i.e., present on day 1 and day 2) hyperoxemia, or excessive oxygen use (FIO2 ≥ 0.60 during hyperoxemia). Results: Of 2005 patients that met the inclusion criteria, 131 (6.5%) were hypoxemic (PaO2 < 55 mmHg), 607 (30%) had hyperoxemia on day 1, and 250 (12%) had sustained hyperoxemia. Excess FIO2 use occurred in 400 (66%) out of 607 patients with hyperoxemia. Excess FIO2 use decreased from day 1 to day 2 of ARDS, with most hyperoxemic patients on day 2 receiving relatively low FIO2. Multivariate analyses found no independent relationship between day 1 hyperoxemia, sustained hyperoxemia, or excess FIO2 use and adverse clinical outcomes. Mortality was 42% in patients with excess FIO2 use, compared to 39% in a propensity-matched sample of normoxemic (PaO2 55-100 mmHg) patients (P = 0.47). Conclusions: Hyperoxemia and excess oxygen use are both prevalent in early ARDS but are most often non-sustained. No relationship was found between hyperoxemia or excessive oxygen use and patient outcome in this cohort. Trial registration: LUNG-SAFE is registered with ClinicalTrials.gov, NCT02010073publishersversionPeer reviewe

    Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

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    Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection
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