1,352 research outputs found
The ESX-3 Secretion System Is Necessary for Iron and Zinc Homeostasis in Mycobacterium tuberculosis
No full textESX-3 is one of the five type VII secretion systems encoded by the Mycobacterium tuberculosis genome. We recently showed the essentiality of ESX-3 for M. tuberculosis viability and proposed its involvement in iron and zinc metabolism. In this study we confirmed the role of ESX-3 in iron uptake and its involvement in the adaptation to low zinc environment in M. tuberculosis. Moreover, we unveiled functional differences between the ESX-3 roles in M. tuberculosis and M. smegmatis showing that in the latter ESX-3 is only involved in the adaptation to iron and not to zinc restriction. Finally, we also showed that in M. tuberculosis this secretion system is essential for iron and zinc homeostasis not only in conditions in which the concentrations of these metals are limiting but also in metal sufficient conditions
Analysis of the microbial communities in soils of different ages following volcanic eruptions
No full textEl primer autor agradece la beca de investigación de la Fundación Alexander von Humboldt y la Sociedad Max Planck, Alemania.The first author acknowledges the research fellowship from the Alexander von Humboldt Foundation and the Max Planck Society, Germany
Valorization of Agrifood By-Products by Extracting Valuable Bioactive Compounds Using Green Processes
No full textIn Chapter 4, Valorization of Agrifood By-Products by Extracting Valuable BioactiveCompounds Using Green Processes, prepared by Carciochi et al., is presented the current challenge for the food industry, related to the exploitation of various by-products as sources of new commodities using eco-friendly technologies with an optimal cost-benefit relationship.The main green technologies used to recover natural products from agrifood by-products, such as enzyme-assisted extraction, ultrasound-assisted extraction, microwave-assisted extraction, electrically assisted extraction, pressurized liquid extraction, supercritical fluid extraction, and instant controlled pressure drop, are presented here.Fil: Carciochi, Ramiro Ariel. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ingeniería Olavarría; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil; ArgentinaFil: D’Alessandro, Leandro G.. Artois University; FranciaFil: Vauchel, Peggy. Charles Viollette Institute; FranciaFil: Rodriguez, Maria Marcela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil; Argentina. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ingeniería Olavarría; ArgentinaFil: Nolasco, Susana Maria. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ingeniería Olavarría; ArgentinaFil: Dimitrov, Krasimir. Lille University; Franci
Synthesis of unsymmetrical derivatives of azaphthalocyanines V.
No full textTitle of diploma thesis: Synthesis of usymmetrical derivates of azaphthalocyanines V. Author: Marcela Nejedlá The aim of diploma thesis was synthesis of unsymmetrical derivates of azaphthalocyanines (Aza- Pc) with carboxy or hydroxy group, and the preparation of suitable precursors of Aza-Pc. Required zinc and magnesium complexes were synthesized using statistical condensation of two different precursors. The desired complex was isolated from the mixture, purified and characterized. The preparation of the precursor 6-(3-tert-butylsulfanyl-5,6-dicyanopyrazine-2- ylamino)hexanoic acid was successful. The cyclization of two precursors yielded the following Aza-Pc: 3-carboxy[2',3'-b]quinoxalino-11,12,18,19,25,26-hexakis(tert- butylsulfanyl)tripyrazino[g,l,q]porphyrazinato zinc (II); 3-carboxy[2',3'-b]quinoxalino- 11,12,18,19,25,26-hexakis(tert-butylsulfanyl)tripyrazino[g,l,q]porphyrazinato magnesium (II). The modification of the preparation of precursor 5,6-dioxo-1,4,5,6-tetrahydropyrazine-2,3- dicarbonitrile by decreasing the reaction temperature has shown to be unsuitabl
Study and comparison of different drying processes for dehydration of raspberries
No full textThe aim of the present study was to evaluate and compare different drying methods (microwave, hot air + microwave, and osmotic dehydration + microwave) in raspberries (cv. Heritage). A portion of raspberries was pretreated with osmotic dehydration (60°Brix sucrose solution at 20°C for 360 min) and another with hot air drying (HAD) (1.5 m/s air speed at 60°C for 300 min). Pretreated raspberries were then dried by microwave and at three different intensities (3.5, 7.5, and 11 W/g). Physicochemical properties (moisture content, water activity, and drying rate) and quality parameters (optical properties, mechanical properties, antioxidant capacity, and rehydration capacity) of dried raspberries were evaluated. Results showed that the microwave drying (MWD) at 7.5 W/g (50 min and final temperature of 79 ± 5.1°C) allowed a high yield of dried raspberries. The combined processes were not efficient to accelerate the decrease of moisture content, due to the low drying rate of the pretreatments. In terms of quality, none of the drying processes allowed a high retention of the antioxidant capacity. However, they allowed an appropriate rehydration performance. The combination of HAD with MWD allowed obtaining a good appearance and desirable texture on the dried product. Thus, this last option seems to be the best among the drying methods tested, but additional studies are required to improve the efficiency of the process and the effect on the antioxidant capacity during drying.Fil: Rodriguez, Anabel. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; ArgentinaFil: Rodriguez, Maria Marcela. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ingeniería Olavarría; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Lemoine, María Laura. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; ArgentinaFil: Mascheroni, Rodolfo Horacio. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentin
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No full textCopper, zinc, mercury and cadmium were studied in muscle, liver and kidney of three adults and one juvenile Southern sea lions, Otaria flavescens, found dead on beaches of Argentina. Heavy metals were determined by Atomic Absorption Spectrophotometry; cold vapor and air/acetylene flame techniques were applied for mercury and for the rest of metals, respectively. Previous acid digestion was made with nitric/sulphuric (Hg) and perchloric/nitric (Cd, Zn, Cu) mixtures. Quality was checked with a Certified Reference Material. Mercury concentrations were highest in liver, whereas cadmium levels were highest in kidney. Juvenile and adults presented the same tissue distribution pattern for all studied metals. Hepatic mercury concentrations ranged from 23.3 m g/g (juvenile female) to 47.6 m g/g (adult male), with renal cadmium concentrations between 0.8 m g/g and 5.7 m g/g, respectively.Fil: Gerpe, Marcela Silvia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Rodriguez, Diego Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Moreno, Victor. Universidad Nacional de Mar del Plata; ArgentinaFil: Bastida, Ricardo Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Aizpún, Julia. Universidad Nacional de Mar del Plata; Argentin
HERVAT strategy from neuroeducation to arrange the attention
No full textLas prácticas de enseñanza vienen innovando gracias a la llegada de la neuroeducación, desde aquí se ve la oportunidad de optimizar las experiencias de aprendizaje a través de la estimulación cognitiva por medio de los sentidos. Por ende, el objetivo de este artículo es presentar los resultados de aplicación del Método neuro educativo Hervat, que por sus siglas integra ejercicios de Hidratación, Equilibrio, Respiración, Audición y Tacto, para mejorar los niveles de atención de 20 estudiantes de grado séptimo de la Institución Educativa Boquía de Salento - Quindío. Se utiliza una metodología mixta aplicando el pretest y postest de Caras-R, a su vez, se realiza una intervención durante 17 sesiones desarrollando los ejercicios del método. Los principales hallazgos muestran la efectividad del método en el postest con una diferencia significativa en el valor p (0.01) lo que sugiere que el método Hervat mejora las aptitudes atencionales de los estudiantes durante sus actividades de aprendizaje incorporando ejercicios sensoriales que pueden implementar en los diversos contextos de su vida. Por su parte, los resultados cualitativos evidencian una percepción favorable de los docentes en cuanto a la aplicación del método, generando una mejor disposición de la atención en diversos momentos de la clase.Magíster en Educación Inclusiva e InterculturalMaestríaTeaching practices have been innovating thanks to the emergence of neuroeducation, which provides an opportunity to optimize learning experiences through brain activation via the senses. Therefore, the objective of this article is to present the validation of the HERVAT neuroeducational method, which, according to its acronym, integrates exercises in Hydration, Balance, Breathing, Hearing, and Touch to improve attentional states in the learning processes of 20 seventh-grade students from the Boquía Educational Institution in Salento, Quindío. A mixedmethod approach is used, applying the Caras-R pretest and posttest, along with an intervention consisting of 17 sessions developing the exercises of the method. The main findings show the effectiveness of the method in the posttest, with a significant difference in the p-value (0.01), suggesting that the HERVAT method enhances students' attentional skills during their learning activities by incorporating sensory exercises that can be applied in various life contexts
The mycobacterial iron-dependent regulator IdeR induces ferritin (bfrB) by alleviating Lsr2 repression
No full textEmerging evidence indicates that precise regulation of iron (Fe) metabolism and maintenance of Fe homeostasis in Mycobacterium tuberculosis (Mtb) are essential for its survival and proliferation in the host. IdeR is a central transcriptional regulator of Mtb genes involved in Fe metabolism. While it is well understood how IdeR functions as a repressor, how it induces transcription of a subset of its targets is still unclear. We investigated the molecular mechanism of IdeR-mediated positive regulation of bfrB, the gene encoding the major Fe-storage protein of Mtb. We found that bfrB induction by Fe required direct interaction of IdeR with a DNA sequence containing four tandem IdeR-binding boxes located upstream of the bfrB promoter. Results of in vivo and in vitro transcription assays identified a direct repressor of bfrB, the histone-like protein Lsr2. IdeR counteracted Lsr2-mediated repression in vitro, suggesting that IdeR induces bfrB transcription by antagonizing the repressor activity of Lsr2. Together, these results elucidate the main mechanism of bfrB positive regulation by IdeR and identify Lsr2 as a new factor contributing to Fe homeostasis in mycobacteria
Alkaloids of the family Amaryllidaceae and their biological aktivity II.
No full textCharles University, Faculty of Pharmacy in Hradec Králové Department: Department of Pharmacognosy (16-16180) Author: Štefan Kosturko Supervisor: PharmDr. Marcela Šafratová, Ph.D. Advisor: PharmDr. Daniela Hulcová, Ph.D. Thesis title: Alkaloids of the family Amaryllidaceae and their biological activity II. Key words: Narcissus pseudonarcissus dutch master; bulbs; alkaloidal extracts; GC/MS analysis; biological activity; acetylcholinesterase; butyrylcholinesterase. The main aim of the thesis ‚,Alkaloids of the family Amaryllidaceae and their biological activity II.'' was the isolation of alkaloids, as a pure substances, in sufficient quantities to identify their structure and to test their biological aktivity in vitro. Alkaloids were separated from subfraction number 82 - 97 of weigh 2,3268 g. This subfraction was a part of the total plant extract, which was prepared by PharmDr. Daniela Hulcová Ph.D., as a part of her dissertation thesis and who also performed primary extraction and separation work. A total and concentrated alkaloid extract weighing 58 g, which included the aforementioned subfraction, was obtained. The already mentioned alkaloid subfraction, was divided by preparative thin-layer chromatography into five separates, which were subjected to further phytochemical work, and five pure..
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(Com)modifying the Sacred: The Incorporation and Adaptation of Non-Western Medicine into the Wellness Tourism Market
No full textIn the last two to three decades, non-mainstream medicine has become a well-known face of the wellness market. Non-mainstream healing constitutes the health and tourism itineraries of a western costumer oriented to self-care and holistic wellbeing. On one hand, these decisions are framed by a western tendency to psychologize our social relationships and seek self-fulfillment in foreign spiritualities. On the other, cultural globalization, the New Age, and new tourisms have contributed to this insertion. Through a de-contextualization of their original cultures and a re-contextualization in western frames, non-mainstream healing is reinvented to adapt to the capitalist economy and the tourist glaze. Such event has aggravated the debate on cultural appropriation of indigenous knowledge. The accommodation of the pre-Hispanic sweat lodge to the hotel industry of Tulum, Mexico, illustrates the present phenomenon. Local healers and hotels negotiate the identity of this ancestral therapeutic ritual, creating a wellness product that bounces between “the hippie” and the luxury in a setting that markets indigenous spirituality. Through a literature review and an ethnographic case study conducted by the author, the present work contributes to understand why and how non-western medicines are constructed within the capitalist wellness market
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