56 research outputs found

    Modelling the Biphasic Growth and Product Formation by Enterococcus faecium CECT 410 in Realkalized Fed-Batch Fermentations in Whey

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    The influence of initial pH on growth and nutrient (total sugars, nitrogen, and phosphorous) consumption by Enterococcus faecium CECT 410 was studied during batch cultures in whey. With these data, two realkalized fed-batch fermentations were developed using different feeding substrates. The shift from homolactic to mixed acid fermentation, the biphasic kinetics observed for cell growth and nitrogen consumption and the increase in the concentrations of biomass and products (lactic acid, acetic acid, ethanol, and butane-2,3-diol) were the most noteworthy observations of these cultures. Modelling the fed-batch growth of Ent. faecium with the Logistic and bi-Logistic models was not satisfactory. However, biomass production was best mathematically described with the use of a double Monod model, which was expressed in terms of biomass, product accumulation, and nitrogen utilization. Product formation was successfully modelled with a modified form of the Luedeking and Piret model developed in this study

    Evaluation of toxic effects of several carboxylic acids on bacterial growth by toxicodynamic modelling

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    <p>Abstract</p> <p>Background</p> <p>Effects of organic acids on microbial fermentation are commonly tested in investigations about metabolic behaviour of bacteria. However, they typically provide only descriptive information without modelling the influence of acid concentrations on bacterial kinetics.</p> <p>Results</p> <p>We developed and applied a mathematical model (secondary model) to capture the toxicological effects of those chemicals on kinetic parameters that define the growth of bacteria in batch cultures. Thus, dose-response kinetics were performed with different bacteria (<it>Leuconostoc mesenteroides</it>, <it>Carnobacterium pisicola</it>, <it>Escherichia coli</it>, <it>Bacillus subtilis </it>and <it>Listonella anguillarum</it>) exposed at increasing concentrations of individual carboxylic acids (formic, acetic, propionic, butyric and lactic). In all bioassays the acids affected the maximum bacterial load (<it>X<sub>m</sub></it>) and the maximum growth rate (<it>v<sub>m</sub></it>) but only in specific cases the lag phase (λ) was modified. Significance of the parameters was always high and in all fermentations the toxicodynamic equation was statistically consistent and had good predictability. The differences between D and L-lactic acid effects were significant for the growth of <it>E. coli</it>, <it>L. mesenteroides </it>and <it>C. piscicola</it>. In addition, a global parameter (<it>EC</it><sub>50,τ</sub>) was used to compare toxic effects and provided a realistic characterization of antimicrobial agents using a single value.</p> <p>Conclusions</p> <p>The effect of several organic acids on the growth of different bacteria was accurately studied and perfectly characterized by a bivariate equation which combines the basis of dose-response theory with microbial growth kinetics (secondary model). The toxicity of carboxylic acids was lower with the increase of the molecular weight of these chemicals.</p

    Effects of feeding of two potentially probiotic preparations from lactic acid bacteria on the performance and faecal microflora of broiler chickens

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    The aim of this study was to evaluate the potential of two probiotic preparations, containing live lactic acid bacteria (Lactococcus lactis CECT 539 and Lactobacillus casei CECT 4043) and their products of fermentation (organic acids and bacteriocins), as a replacement for antibiotics in stimulating health and growth of broiler chickens. The effects of the supplementation of both preparations (with proven probiotic effect in weaned piglets) and an antibiotic (avilamycin) on body weight gain (BWG), feed intake (FI), feed consumption efficiency (FCE), relative intestinal weight, and intestinal microbiota counts were studied in 1- day posthatch chickens. The experiments were conducted with medium-growth Sasso X44 chickens housed in cages and with nutritional stressed Ross 308 broiler distributed in pens. Consumption of the different diets did not affect significantly the final coliform counts in Sasso X44 chickens. However, counts of lactic acid bacteria and mesophilic microorganisms were higher in the animals receiving the two probiotic preparations (P < 0.05). In the second experiment, although no differences in BWG were observed between treatments, Ross 308 broilers receiving the probiotic Lactobacillus preparation exhibited the lowest FCE values and were considered the most efficient at converting feed into live weight.Instituto Nacional de Investigación y Tecnología Agraria | Ref. CAL01-045-C2-

    Aplicabilidad de los principios de la justicia de John Rawls en la distribución de las regalías en Colombia: una perspectiva socio jurídica y filosófica de la minería colombiana desde la teoría de justicia de Rawls

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    Artículo de investigaciónEl presente artículo busca realizar el análisis de la actividad minera en Colombia bajo el enfoque de los principios de justicia manejados por Rawls en su teoría de la justicia. Motivo por el cual, dentro del presente texto se abordarán conceptos como eficacia, validez, legitimidad, entre otros desde un enfoque distribucionista de deberes y beneficios en la normatividad vigente presentada por las instituciones encargadas regular la actividad minera en Colombia.41 p.RESUMEN ABSTRACT INTRODUCCIÓN 1. La mineria en Ciolombia 2. El concepto de justicia y su entorno social 3. el problema de la maximizacion de la riqueza frente al principio de diferencia 4. Legitimidad vs legalidad en el derecho minero CONCLUSIONES. REFERENCIASPregradoAbogad

    Emperador Julio César

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    10 p.Julio César fue considerado un emperador de la Antigua Roma, como dictador y una de las primeras figuras en el ámbito político y militar, además fue escritor y como un gran elocuente; orador distinguido. A pesar de estar considerado como el aristócrata vivo de más rancio abolengo de Roma (su árbol genealógico llegaba hasta la propia diosa Venus, según las tradiciones romanas); pero así mismo fue uno de los personajes más admirados por hacer historia con sus grandes hazañas militares. Entre esas: la gran conquista de Galia; llevando a cabo a conseguir con la lucha política el poder absolutista del Imperio, acabando con sus enemigos que estaban liderados por Pompeyo. Una vez conseguido el poder y habiéndose proclamado senador vitalicio o perpetuo, se preparó un complot orquestado por varios senadores para matarlo, entre varios de sus hombres de confianza.ACTOS DE PRUDENCIA DE JULIO CÉSAR REFERENCIA

    Modelling the biphasic growth and product formation by Enterococcus faecium CECT 410 in realkalized fed-batch fermentations in whey

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    The influence of initial pH on growth and nutrient (total sugars, nitrogen, and phosphorous) consumption by Enterococcus faecium CECT 410 was studied during batch cultures in whey. With these data, two realkalized fed-batch fermentations were developed using different feeding substrates. The shift from homolactic to mixed acid fermentation, the biphasic kinetics observed for cell growth and nitrogen consumption and the increase in the concentrations of biomass and products (lactic acid, acetic acid, ethanol, and butane-2,3-diol) were the most noteworthy observations of these cultures. Modelling the fed-batch growth of Ent. faecium with the Logistic and bi-Logistic models was not satisfactory. However, biomass production was best mathematically described with the use of a double Monod model, which was expressed in terms of biomass, product accumulation, and nitrogen utilization. Product formation was successfully modelled with a modified form of the Luedeking and Piret model developed in this study.Instituto Nacional de Investigación y Tecnología Agraria | Ref. CAL01-045-C2-2Ministerio de Educación y Ciencia | Ref. MAT2005-05393-C03-03Ministerio de Educación y Ciencia | Ref. MAT2006-11662- C03-0

    Effectiveness of Mental Health Literacy Programs in Primary and Secondary Schools : a Systematic Review with Meta-Analysis

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    Altres ajuts: IDIAP: 7Z20/010- 2020; Generalitat de Catalunya (PERIS) SLT002/16/00202In recent years, there has been an increase in studies evaluating the effectiveness of mental health literacy programs within the context of education as a universal, preventive intervention. A systematic review and meta-analysis regarding the effectiveness of mental health literacy interventions in schools, from 2013 to the present, on mental health knowledge, stigma, and help-seeking is conducted. Of the 795 identified references, 15 studies met the inclusion criteria. Mental health knowledge increased after the interventions (standardized mean difference: SMD = 0.61; 95% CI (0.05, 0.74)), at two months (SMD = 0.60; 95% CI (0.4, 1.07)) and six months (SMD = 0.39; 95% CI (0.27, 0.51)). No significant differences were observed between stigma and improving help-seeking. Mental health literacy interventions are effective in augmenting mental health knowledge, but not in reducing stigma or improving help-seeking behavior

    Fabry Nephropathy: An Evidence-Based Narrative Review.

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    Fabry disease (FD) is a rare, X-linked disorder caused by mutations in the GLA gene encoding the enzyme α-galactosidase A. Complete or partial deficiency in this enzyme leads to intracellular accumulation of globotriaosylceramide (Gb3) and other glycosphingolipids in many cell types throughout the body, including the kidney. Progressive accumulation of Gb3 in podocytes, endothelial cells, epithelial cells, and tubular cells contribute to the renal symptoms of FD, which manifest as proteinuria and reduced glomerular filtration rate leading to renal insufficiency. A correct diagnosis of FD, although challenging, has considerable implications regarding treatment, management, and counseling. The diagnosis may be confirmed by demonstrating the enzyme deficiency in males and by identifying the specific GLA gene mutation in male and female patients. Treatment with enzyme replacement therapy, as part of the therapeutic strategy to prevent complications of the disease, may be beneficial in stabilizing renal function or slowing its decline, particularly in the early stages of the disease. Emergent treatments for FD include the recently approved chaperone molecule migalastat for patients with amenable mutations. The objective of this report is to provide an updated overview on Fabry nephropathy, with a focus on the most relevant aspects of its epidemiology, diagnosis, pathophysiology, and treatment options.S

    Influence of single-nucleotide polymorphisms in TLR3 (rs3775291) and TLR9 (rs352139) on the risk of CMV infection in kidney transplant recipients

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    Risk stratification for cytomegalovirus (CMV) infection after kidney transplantation (KT) remains to be determined. Since endosomal toll-like receptors (TLRs) are involved in viral sensing, we investigated the impact of common single-nucleotide polymorphisms (SNPs) located within TLR3 and TLR9 genes on the occurrence of overall and high-level (≥1,000 IU/ml) CMV infection in a cohort of 197 KT recipients. Homozygous carriers of the minor allele of TLR3 (rs3775291) had higher infection-free survival compared with reference allele carriers (60.0% for TT versus 42.3% for CC/CT genotypes; P-value = 0.050). Decreased infection-free survival was observed with the minor allele of TLR9 (rs352139) (38.2% for TC/CC versus 59.3% for TT genotypes; P-value = 0.004). After multivariable adjustment, the recessive protective effect of the TLR3 (rs3775291) TT genotype was confirmed (adjusted hazard ratio [aHR]: 0.327; 95% CI: 0.167–0.642; P-value = 0.001), as was the dominant risk-conferring effect of TLR9 (rs352139) TC/CC genotypes (aHR: 1.865; 95% CI: 1.170–2.972; P-value = 0.009). Carriers of the TLR9 (rs352139) TC/CC genotypes showed lower CMV-specific interferon-γ-producing CD4+ T-cell counts measured by intracellular cytokine staining compared with the TT genotype (median of 0.2 versus 0.7 cells/μl; P-value = 0.003). In conclusion, TLR3/TLR9 genotyping may inform CMV infection risk after KT

    Postlaunch evidence-generation studies for medical devices in Spain: the RedETS approach to integrate real-world evidence into decision making

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    The Monitoring Studies (MS) program, the approach developed by RedETS to generate postlaunch real-world evidence (RWE), is intended to complement and enhance the conventional health technology assessment process to support health policy decision making in Spain, besides informing other interested stakeholders, including clinicians and patients. The MS program is focused on specific uncertainties about the real effect, safety, costs, and routine use of new and insufficiently assessed relevant medical devices carefully selected to ensure the value of the additional research needed, by means of structured, controlled, participative, and transparent procedures. However, despite a clear political commitment and economic support from national and regional health authorities, several difficulties were identified along the development and implementation of the first wave of MS, delaying its execution and final reporting. Resolution of these difficulties at the regional and national levels and a greater collaborative impulse in the European Union, given the availability of an appropriate methodological framework already provided by EUnetHTA, might provide a faster and more efficient comparative RWE of improved quality and reliability at the national and international levels
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