50 research outputs found

    Dehydration tolerance in yeast

    Get PDF
    La habilidad de las levaduras de superar la deshidratación y de reactivar su metabolismo después de la rehidratación tiene una importancia en la industria de los alimentos y en la biotecnología. Nosotros hemos dirigido nuestro trabajo a mejorar la viabilidad y vitalidad de las levaduras después de la rehidratación. Se realizaron estudios desde el punto de vista fisiológico de las levaduras durante la optimización de las condiciones de rehidratación y estudios moleculares como la determinación de los genes esenciales de respuesta a Secado y Rehidratación (SR) y la caracterización de la muerte celular a consecuencia del SR. Se sobre expresaron genes que codifican péptidos que permiten superar la viabilidad alcanzada por las levaduras bajo estas condiciones de estrés.Hipótesis de partida:Algunos metabolitos y genes esenciales de respuesta a estrés por secado y rehidratación permiten a las levaduras tolerar la desecaciónThe ability of yeast to overcome dehydration and restart metabolism after rehydration has an importance in the food industry and biotechnology. We have directed our work to improve the viability and vitality of the yeast after rehydration. The studies were conducted in one hand from the physiological point of view to optimize rehydration conditions, and in the other hand from the molecular point of view. We identified the essential genes in response to drying and rehydration and its role in yeast cell death. Moreover we study the effect of over expressed some of this genes on yeast desiccation tolerance.Hypothesis: Some metabolites and essential genes in response to stress during drying and rehydration allow yeasts tolerate desiccation

    Design and Optimization of a Mycoplasma Detection Assay

    Full text link
    Mycoplasma are among the smallest free living microorganisms. These bacteria grow slowly, lack a rigid cell wall and are not eliminated by filter sterilization methods used in tissue culture. Mycoplasma infection affects biochemical and genetic aspects of cultured cells, resulting in experimental inconsistency. Therefore, it is necessary to establish routine testing for mycoplasma contamination in tissue culture laboratories. Our goal is to develop a reliable and cost-effective test for mycoplasma in cell culture based on established methods found in literature. We first cloned and sequenced a PCR product from a commercial mycoplasma detection kit. Sequencing revealed the 16s rRNA as the target for mycoplasma detection; we confirmed this target by conducting a literature search. PCR primers were designed using 16s rRNA gene as a target. We set-up reactions and optimized conditions for the real-time PCR assay to detect the target and confirmed amplicon size with agarose gel electrophoresis. We identified that 56oC was the best temperature for the PCR and found that agarose gel electrophoresis was a better detection method because it identified the size to confirm the proper product. The primers we ordered to develop this assay produce the proper band; however, results of several assays have been inconsistent as sometimes a known positive sample fails to amplify. As well, in several PCR reactions the negative showed a signal. The overall reaction needs improvements to have greater reliability and to eliminate all sources of contamination. Research is continuing results are not final

    Medium- and Short-Term Interventions with Ma-Pi 2 Macrobiotic Diet in Type 2 Diabetic Adults of Bauta, Havana

    Get PDF
    Background. In Cuba, the Ma-Pi 2 macrobiotic diet has shown positive results in 6-month assays with type 2 diabetic patients. The objective of this study was to assess the influence of this diet at short and medium terms. Methods. Sixty-five type 2 diabetic volunteers were included for dietary intervention, institutionally based for 21 days and followed later at home, until completing 3 months. 54 of them stayed until assay end. Before intervention, and after both assay periods, they were submitted to anthropometric records, body composition analyses and measurements of serum biochemical indicators, glycemic profile in capillary blood, blood pressure, and medication consumption; food intake was evaluated by the 3-day dietary recall. Results. During the intervention, the energy intake was 200 kcal higher at instance of more complex carbohydrates and dietary fiber and despite less fat and protein. Blood pressure and serum biochemical indicators decreased significantly in both periods; the safety nutritional indicators (hemoglobin, serum total proteins, and albumin) showed no variations. The global cardiovascular risk decreased and insulin consumption dropped by 46% and 64%, in both periods, respectively. Conclusions. The Ma-Pi 2 macrobiotic diet was a successful therapy at short term and after 3-month home-based intervention, for type 2 diabetics

    Nutritional screening and prevalence of hospital malnutrition risk. University Hospital of the UANL, Monterrey

    Get PDF
    Introduction: Hospital malnutrition risk has prevalence values of 20%-50%, and it is a major health problem in the health institutions worldwide. Objective: To assess the accomplishment of nutritional screening and the prevalence of hospital malnutrition risk in a University Hospital. Materials and methods: A retrospective analysis was carried out with nutritional screening, using primary data from six clinical areas obtained in the period between July 2012 and December 2013. According to previous results in Mexican health institutions and considering a mean malnutrition risk prevalence of 50%, it was calculated that a sample size of 3200 subjects was required for the assessment of valid risk values. Patients with values ≥3 on the Nutritional Risk Screening (NRS, 2002) were classiied as carriers of nutritional risk. Results: A total of 5611 patients (38% of all patients admitted) were studied. The rate of screening declined from 55% in 2012 to 31% in 2013. During the whole period, 3034 patients were classiied with risk of malnutrition (54% prevalence). Conclusions: The prevalence of hospital malnutrition risk was high. The accomplishment of the nutritional screening was deicient, and declined between 2012 and 2013. The lack of nutritional screening does not meet the vital care requirements of hospitalized patients and prevents the timely treatment of those at malnutrition risk

    The STF2p Hydrophilin from Saccharomyces cerevisiae Is Required for Dehydration Stress Tolerance

    Get PDF
    The yeast Saccharomyces cerevisiae is able to overcome cell dehydration; cell metabolic activity is arrested during this period but restarts after rehydration. The yeast genes encoding hydrophilin proteins were characterised to determine their roles in the dehydration-resistant phenotype, and STF2p was found to be a hydrophilin that is essential for survival after the desiccation-rehydration process. Deletion of STF2 promotes the production of reactive oxygen species and apoptotic cell death during stress conditions, whereas the overexpression of STF2, whose gene product localises to the cytoplasm, results in a reduction in ROS production upon oxidative stress as the result of the antioxidant capacity of the STF2p protein

    Limits to the muon flux from WIMP annihilation in the center of the Earth with the AMANDA detector

    Full text link
    A search for nearly vertical up-going muon-neutrinos from neutralino annihilations in the center of the Earth has been performed with the AMANDA-B10 neutrino detector. The data sample collected in 130.1 days of live-time in 1997, ~10^9 events, has been analyzed for this search. No excess over the expected atmospheric neutrino background is oberved. An upper limit at 90% confidence level on the annihilation rate of neutralinos in the center of the Earth is obtained as a function of the neutralino mass in the range 100 GeV-5000 GeV, as well as the corresponding muon flux limit.Comment: 14 pages, 11 figures. Version accepted for publication in Physical Review

    Análisis de la opinión de estudiantes sobre conductas de riesgo de jóvenes en Puerto Rico

    Get PDF
    The main purpose of the study was to analyze the opinion that students of the University of Puerto Rico, Río Piedras Campus (UPRRP) have about some risk behaviors in teenagers of both genders between the ages of 13-18. We administered an online survey, which was taken by 1,836 students enrolled during the first semester of the 2017-18 academic year. We used mixed methods: descriptive statistics analysis and content analysis. The findings reveal that the opinion of students is that youth is a stage of confusion and turbulence; that some risk behaviors have increased during the past five years and that it tends to be associated to male youth. These results suggest that university students tend to reproduce the dominant social imaginary in terms of risk behavior in youth. Further investigations should take into consideration the consequences of youth stigmatization, since this is a heterogeneous and diverse group.El objetivo de nuestro estudio fue analizar la opinión que tienen los/as estudiantes de la Universidad de Puerto Rico, Recinto de Río Piedras (UPRRP), sobre algunas conductas de riesgo en jóvenes de ambos géneros, de 13-18 años.  Administramos un cuestionario en línea que fue contestado por 1,836 estudiantes matriculados/as durante el primer semestre del año académico 2017-18. Utilizamos un método mixto: análisis estadístico descriptivo y análisis de contenido. Los hallazgos revelan que la opinión de la mayoría de los/as estudiantes universitarios/as es que la juventud es una etapa de confusión y turbulencia; que algunas conductas de riesgo han aumentado durante los pasados cinco años y que se asocian más con los jóvenes que con las jóvenes. Estos hallazgos sugieren que los/as estudiantes tienden a reproducir los imaginarios sociales dominantes sobre la conducta de riesgo en jóvenes entre las edades de 13-18 años. Futuros trabajos deben considerar las consecuencias de la estigmatización hacia los/as jóvenes, ya que este es un grupo heterogéneo y variado

    New results from the Antarctic Muon And Neutrino Detector Array

    Full text link
    We present recent results from the Antarctic Muon And Neutrino Detector Array (AMANDA) on searches for high-energy neutrinos of extraterrestrial origin. We have searched for a diffuse flux of neutrinos, neutrino point sources and neutrinos from GRBs and from WIMP annihilations in the Sun or the center of the Earth. We also present a preliminary result on the first energy spectrum above a few TeV for atmospheric neutrinos.Comment: 8 pages, 8 figures, to be published in Nuclear Physics B (Proceedings Supplement): Proceedings of the XXIst International Conference on Neutrino Physics and Astrophysics, Paris, June 14-19, 200

    Flux limits on ultra high energy neutrinos with AMANDA-B10

    Get PDF
    Abstract Data taken during 1997 with the AMANDA-B10 detector are searched for a diffuse flux of neutrinos of all flavors with energies above 10 16 eV. At these energies the Earth is opaque to neutrinos, and thus neutrino induced events are concentrated at the horizon. The background are large muon bundles from down-going atmospheric air shower events. No excess events above the background expectation are observed and a neutrino flux following E À2 , with an equal mix of all flavors, is limited to E 2 U(10 15 eV < E < 3 · 10 18 eV) 6 0.99 · 10 À6 GeV cm À2 s À1 sr À1 at 90% confidence level. This is the most restrictive experimental bound placed by any neutrino detector at these energies. Bounds to specific extraterrestrial neutrino flux predictions are also presented. Ó 2004 Elsevier B.V. All rights reserved. PACS: 95.55.Vj; 95.85.Ry; 96.40.T
    corecore