Eduardo Torres
Ontario College of Art And Design, Environmental Design, Undergraduate
The World Health Organization indicates that more than 1.5 billion people are infected with geohelminths. Soil-transmitted helminths prevail mostly in tropical and subtropical regions, in areas with inadequate hygiene and sanitation... more
The World Health Organization indicates that more than 1.5 billion people are infected with geohelminths. Soil-transmitted helminths prevail mostly in tropical and subtropical regions, in areas with inadequate hygiene and sanitation conditions, and basic health education problems. Nematode eggs are structures of resistance and infection by fecal–oral transmission. When STH eggs are ingested, they can infect the potential host, causing abdominal pain, diarrhea, anemia, malnutrition, and physical-cognitive impacts in children. Taking advantage of the increasing employment of three-dimensional models of these structured based on light microscopy images to improve the research area and education could be an alternative to improve health education and spread scientific information on transmission and prevention. The objective of this work was to produce 3D printed models from bi-dimensional images of eggs based on their real morphological and morphometric characteristics. The virtual mod...
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Due to its chemical properties, glyphosate [N-(phosphonomethyl)glycine] is one of the most commonly used agricultural herbicides globally. Due to risks associated with human exposure to glyphosate and its potential harmfulness, the need... more
Due to its chemical properties, glyphosate [N-(phosphonomethyl)glycine] is one of the most commonly used agricultural herbicides globally. Due to risks associated with human exposure to glyphosate and its potential harmfulness, the need to develop specific, accurate, online, and sensitive methods is imperative. In accordance with this, the present review is focused on recent advances in developing nanomaterial-based sensors for glyphosate detection. Reported data from the literature concerning glyphosate detection in the different matrices using analytical methods (mostly chromatographic techniques) are presented; however, they are expensive and time-consuming. In this sense, nanosensors’ potential applications are explained to establish their advantages over traditional glyphosate detection methods. Zero-dimensional (0D), one-dimensional (1D), two-dimensional (2D), and three- dimensional (3D) materials are reviewed, from biomolecules to metallic compounds. Bionanomaterials have gen...
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RESUMO Este trabalho reporta a bioprospecção de lipases de fungos de sedimentos marinhos da Costa Cearense (Nordeste Brasileiro). Cinco cepas fúngicas foram isoladas de sedimentos marinhos (SM1-SM5), coletados na Barra do Ceará,... more
RESUMO Este trabalho reporta a bioprospecção de lipases de fungos de sedimentos marinhos da Costa Cearense (Nordeste Brasileiro). Cinco cepas fúngicas foram isoladas de sedimentos marinhos (SM1-SM5), coletados na Barra do Ceará, Fortaleza-CE. Foram submetidos ao teste de atividade lipolítica através do método de difusão em gel, utilizando-se o azeite de oliva como substrato específico de lipases e tributirina para esterases. Rodamina B foi utilizado como o reagente colorimétrico. Das cinco cepas fúngicas testadas, três (SM1, SM2 e SM3) se mostraram ativas especificamente para atividade de lipases (AL), apresentando de moderada a elevada AL (2,4 <AL ≤ 3,8). Dentre essas, um (SM2) apresentou elevada atividade lipolítica, com valor de AL igual a 3,8, significantemente semelhante ao controle positivo (Aspergillus niger). Os isolados foram identificados de acordo com suas características morfológicas e classificados como Paecilomyces sp. (SM1), Aspergillus sp. (SM2) e Aspergillus flav...
The indiscriminate use and mismanagement of antibiotics over the last eight decades have led to one of the main challenges humanity will have to face in the next twenty years in terms of public health and economy, i.e., antimicrobial... more
The indiscriminate use and mismanagement of antibiotics over the last eight decades have led to one of the main challenges humanity will have to face in the next twenty years in terms of public health and economy, i.e., antimicrobial resistance. One of the key approaches to tackling antimicrobial resistance is clinical, livestock, and environmental surveillance applying methods capable of effectively identifying antimicrobial non-susceptibility as well as genes that promote resistance. Current clinical laboratory practices involve conventional culture-based antibiotic susceptibility testing (AST) methods, taking over 24 h to find out which medication should be prescribed to treat the infection. Although there are techniques that provide rapid resistance detection, it is necessary to have new tools that are easy to operate, are robust, sensitive, specific, and inexpensive. Chemical sensors and biosensors are devices that could have the necessary characteristics for the rapid diagnosi...
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E com humildade que me dirijo a uma plateia com alguns dos maiores especialistas em literacia mediatica do pais. Nao querendo ensinar o conto ao vigario, aqui deixo dez ideias em forma de telegramas...
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O objetivo do trabalho foi conscientizar o produtor sobre a importância da adocao de boas praticas agropecuarias a fim de tornar propriedade rural sustentavel, economica, social e ambientalmente correta. Foram executadas acoes de... more
O objetivo do trabalho foi conscientizar o produtor sobre a importância da adocao de boas praticas agropecuarias a fim de tornar propriedade rural sustentavel, economica, social e ambientalmente correta. Foram executadas acoes de recuperacao de areas degradadas em uma propriedade rural no municipio de Miranda, cadastrado pelo SENAR, sendo uma fazenda incluida nesse projeto, diferente da proposta inicial de duas fazendas. Na fazenda Sanguessuga, no municipio de Miranda – MS, o proprietario Massao Ohata recebeu orientacoes tecnicas de um profissional do SENAR, responsaveis pela execucao do projeto, alem de um tecnico da FUNDACÂO MS, juntamente com a academica bolsista e seu respectivo orientador professor Francisco Eduardo Torres para a implantacao e desenvolvimento das recomendacoes para melhoria do processo produtivo de acordo com o cronograma de execucao das atividades incluindo amostragem de solo, aplicacao de insumos e operacoes mecânicas de manejo. As areas eram formadas por cap...
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Advances generated in medicine, science, and technology have contributed to a better quality of life in recent years; however, antimicrobial resistance has also benefited from these advances, creating various environmental and health... more
Advances generated in medicine, science, and technology have contributed to a better quality of life in recent years; however, antimicrobial resistance has also benefited from these advances, creating various environmental and health problems. Several determinants may explain the problem of antimicrobial resistance, such as wastewater treatment plants that represent a powerful agent for the promotion of antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARG), and are an important factor in mitigating the problem. This article focuses on reviewing current technologies for ARB and ARG removal treatments, which include disinfection, constructed wetlands, advanced oxidation processes (AOP), anaerobic, aerobic, or combined treatments, and nanomaterial-based treatments. Some of these technologies are highly intensive, such as AOP; however, other technologies require long treatment times or high doses of oxidizing agents. From this review, it can be concluded that treatme...
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Glyphosate is a broad-spectrum herbicide widely used worldwide. Indeed, it is the herbicide most applied to all Mexican crops. Due to the overuse and poor disposal of the waste, this herbicide can reach the aquatic environments such as... more
Glyphosate is a broad-spectrum herbicide widely used worldwide. Indeed, it is the herbicide most applied to all Mexican crops. Due to the overuse and poor disposal of the waste, this herbicide can reach the aquatic environments such as groundwater and surface water. Thus, there is a clear need to implement monitoring and surveillance programs for evaluating and controlling the exposure to this herbicide in rural populations. The goal of this study was to quantify the presence of glyphosate in different water bodies (groundwater, surface and drinking water) as well as to identify the uses and managements of water resources by rural communities to evaluate the potential human exposure to glyphosate in the Tenampulco region of the Mexican state of Puebla. Measurements were performed by a rapid and cost-effective ELISA-based method in groundwater and surface water from various sampling sites of the Tenampulco region. Glyphosate was detected in all groundwater samples to be below the max...
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Infections with Trichuris trichiura are among the most common causes of intestinal parasitism in children worldwide, and the diagnosis is based on microscopic egg identification in the chronic phase of the infection. During parasitism,... more
Infections with Trichuris trichiura are among the most common causes of intestinal parasitism in children worldwide, and the diagnosis is based on microscopic egg identification in the chronic phase of the infection. During parasitism, the adult worm of the trichurid nematode maintains its anterior region inserted in the intestinal mucosa, which causes serious damage and which may open access for gut microorganisms through the intestinal tissue.
Research Interests: Microbiology, Immunology, Immune response, Biology, Medicine, and 15 moreBiological Sciences, Infection and immunity, Intestinal Mucosa, Infectious Disease, Intestine, Helminth, Nematodes, Ciencias Biológicas, Trichuris, Microbiota, Enseñanza - Aprendizaje Ciencias Naturales Y Exactas, Trichuris Trichiura, Trichuriasis, Trichuris muris, and Medical and Health Sciences
El propósito de este artículo es analizar empíricamente la relación confianza-compromiso en el contexto de la banca en internet. Para lograr este objetivo, se aplicó una encuesta telefónica a un grupo de clientes de la banca en internet... more
El propósito de este artículo es analizar empíricamente la relación confianza-compromiso en el contexto de la banca en internet. Para lograr este objetivo, se aplicó una encuesta telefónica a un grupo de clientes de la banca en internet en Chile y se analizó detalladamente la estructura dimensional de la confianza. Por medio de un modelo de ecuaciones estructurales se pudo comprobar el efecto positivo y directo que tiene la confianza sobre el compromiso en el contexto de estudio. Además, se pudo determinar que la confianza en la banca en Internet tiene una estructura multidimensional constituida por la honestidad, benevolencia y competencia. Estos resultados otorgan a los bancos un conocimiento respecto a cuáles son los factores que deben gestionar para lograr el compromiso de los clientes que realizan transacciones a través de internet, principalmente en un contexto latinoamericano
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A spectrophotometric method for the determination of glyphosate based on the monitoring of a complex formation between bis 5-phenyldipyrrinate of nickel (II) and the herbicide was developed. The method showed a short response time (10 s),... more
A spectrophotometric method for the determination of glyphosate based on the monitoring of a complex formation between bis 5-phenyldipyrrinate of nickel (II) and the herbicide was developed. The method showed a short response time (10 s), high selectivity (very low interference from other pesticides and salts), and high sensitivity (LOD 2.07 × 10−7 mol/L, LOQ 9.87 × 10−7 mol/L, and a Kd from 1.75 × 10−6 to 6.95 × 10−6 mol/L). The Job plot showed that complex formation occurs with a 1:1 stoichiometry. The method was successfully applied in potable, urban, groundwater, and residual-treated water samples, showing high precision (0.34–2.9%) and accuracy (87.20–119.04%). The structure of the complex was elucidated through theoretical studies demonstrating that the nickel in the bis 5-phenyldipyrrinate forms a distorted octahedral molecular geometry by expanding its coordination number through one bond with the nitrogen and another with the oxygen of the glyphosate’ carboxyl group, at dis...
Research Interests: Chemistry, Water, Sensor, Multidisciplinary, Glyphosate, and 3 moreNickel, Stoichiometry, and Selectivity
Glyphosate (-(phosphonomethyl)glycine) is the most frequently used broad-spectrum herbicide worldwide. Its mechanism of action is based on the inhibition of an enzyme that is essential to plant growth. Its intensive use has caused global... more
Glyphosate (-(phosphonomethyl)glycine) is the most frequently used broad-spectrum herbicide worldwide. Its mechanism of action is based on the inhibition of an enzyme that is essential to plant growth. Its intensive use has caused global contamination to occur, which has not only affected the ecosystems, but even food and other objects of common use. Thus, there is a pronounced need for developing analytical methods for glyphosate determination in different matrices. Here, an electrochemical competitive immunoassay, based on the use of antibody-modified magnetic particles, has been developed. Tetramethylbenzidine (TMB) has been used as an enzymatic substrate. The extent of the affinity reaction has been achieved by monitoring the current value, due to the reduction of the enzymatic product. A disposable screen-printed electrochemical cell has been used. The calibration curve has been recorded in the 0⁻10,000 ng/L concentration range, with a detection limit of 5 ng/L and quantificati...
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Trabajos en altura
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In recent years, the continuous and accumulative discharge of toxic and contaminating compounds to the environment makes necessary to propose precise and quick methods for their detection and quantitation. Especially when one considers... more
In recent years, the continuous and accumulative discharge of toxic and contaminating compounds to the environment makes necessary to propose precise and quick methods for their detection and quantitation. Especially when one considers that the environmental impact of some of these emerging contaminants has not been clearly determined. Enzyme-based biosensors are an interesting alternative when inspecting different pollutants present in the environment in a quick, efficient, automatized, and economic way. Oxidative enzymes such as peroxidases and polyphenol oxidases (laccases and tyrosinases) are versatile and highly functional enzymes used for analyte recognition. Therefore, these enzymes are considered attractive and interesting biomolecules to act as recognition elements in biosensors. In this regard, detection of pollutants such as pesticides, phenols, heavy metals, and pharmaceutical compounds by using oxidative enzymes as recognition elements in biosensors is a versatile field...
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Aneuploidy causes severe developmental defects and is a near universal feature of tumor cells. Despite its profound effects, the cellular processes affected by aneuploidy are not well characterized. Here, we examined the consequences of... more
Aneuploidy causes severe developmental defects and is a near universal feature of tumor cells. Despite its profound effects, the cellular processes affected by aneuploidy are not well characterized. Here, we examined the consequences of aneuploidy on the proteome of aneuploid budding yeast strains. We show that although protein levels largely scale with gene copy number, subunits of multi-protein complexes are notable exceptions. Posttranslational mechanisms attenuate their expression when their encoding genes are in excess. Our proteomic analyses further revealed a novel aneuploidy-associated protein expression signature characteristic of altered metabolism and redox homeostasis. Indeed aneuploid cells harbor increased levels of reactive oxygen species (ROS). Interestingly, increased protein turnover attenuates ROS levels and this novel aneuploidy-associated signature and improves the fitness of most aneuploid strains. Our results show that aneuploidy causes alterations in metaboli...
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Research Interests: Endocrinology, Medicine, Internal Medicine, Female, Ovulation, and 13 moreAnimals, Dairy Cow, Cattle, Pituitary Gland, Gonadotropin Releasing Hormone, Adrenocorticotropic Hormone, Veterinary Sciences, Ovary, Luteinizing Hormone, Adrenal glands, Adrenal Function, postpartum period, and hydrocortisone
Aneuploidy, or an aberrant karyotype, results in developmental disabilities and has been implicated in tumorigenesis. However, the causes of aneuploidy-induced phenotypes and the consequences of aneuploidy on cell physiology remain poorly... more
Aneuploidy, or an aberrant karyotype, results in developmental disabilities and has been implicated in tumorigenesis. However, the causes of aneuploidy-induced phenotypes and the consequences of aneuploidy on cell physiology remain poorly understood. We have performed a metaanalysis on gene expression data from aneuploid cells in diverse organisms, including yeast, plants, mice, and humans. We found highly related gene expression patterns that are conserved between species: genes that were involved in the response to stress were consistently upregulated, and genes associated with the cell cycle and cell proliferation were downregulated in aneuploid cells. Within species, different aneuploidies induced similar changes in gene expression, independent of the specific chromosomal aberrations. Taken together, our results demonstrate that aneuploidies of different chromosomes and in different organisms impact similar cellular pathways and cause a stereotypical antiproliferative response t...
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PurposeThis paper analyzes how consumers’ perceptions of their traditional bank influence their decision to adopt the services offered by the same bank on the internet. Design/methodology/approach – The data required in this paper were... more
PurposeThis paper analyzes how consumers’ perceptions of their traditional bank influence their decision to adopt the services offered by the same bank on the internet. Design/methodology/approach – The data required in this paper were gathered by means of a personal survey conducted with customers of various banks totaling 633, which distribute their services by traditional channels as well as on the internet. A Binomial Logistic Regression process was analyzed to assess the influence of trust, incomes, age, sex, education and employment on the adoption of the financial services offered by a traditional bank on the internet. Findings – The results in the paper showed that consumer trust in a traditional bank, as well as incomes, age and sex are factors that influence consumers’ decision to work with the same bank via the internet. Research limitations/implications – The paper shows that, turning to the limitations of the work, it is necessary to point out that the majority of indiv...
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The use of biomass to produce renewable energy is one of the forms that can be used to reduce the impact of energy production. Like any other energy resource, there are limitations for biomass use, and it must compete not only with fossil... more
The use of biomass to produce renewable energy is one of the forms that can be used to reduce the impact of energy production. Like any other energy resource, there are limitations for biomass use, and it must compete not only with fossil fuels but also with other renewable energy sources such as solar or wind energy. Combustion is currently the most efficient and widely used waste-to-energy process, in the areas where direct use of biomass is possible, without the need to make large transfers of raw material. Many industrial facilities can use agricultural or forestry waste, straw, chips, bagasse, etc. in their thermal systems without making major transformations or adjustments in the feeding to the ovens, making this waste an attractive and cost-effective option in terms of availability, access, and costs. In spite of the facilities and benefits, the environmental reasons (emission of gases and particulate material) are decisive for its use for energy purpose. This paper describes...
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The Internet is now used to present photographic exhibitions. This is my review of the exhibition Power to the People, of photographies of crowds at the beginning of the twentieth century, available at... more
The Internet is now used to present photographic exhibitions. This is my review of the exhibition Power to the People, of photographies of crowds at the beginning of the twentieth century, available at www.europeana.eu/portal/en/exhibitions/power-to-the-people
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Pesticides, due to their intensive use and their peculiar chemical features, can persist in the environment and enter the trophic chain, thus representing an environmental risk for the ecosystems and human health. Although there are... more
Pesticides, due to their intensive use and their peculiar chemical features, can persist in the environment and enter the trophic chain, thus representing an environmental risk for the ecosystems and human health. Although there are several robust and reliable standard analytical techniques for their monitoring, the high frequency of contamination caused by pesticides requires methods for massive monitoring campaigns that are capable of rapidly detecting these compounds in many samples of different origin. Immunosensors represent a potential tool for simple, rapid, and sensitive monitoring of pesticides. Antibodies coupled to electrochemical or optical transducers have resulted in effective detection devices. In this review, the new trends in immunosensor development and the application of immunosensors for the detection of pesticides of environmental concern—such as glyphosate, organophosphates, and neonicotinoids—are described.
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Broadcast television and its audiences live a paradoxical situation: on the one hand, channels still schedule according to the concept of flow; on the other hand, viewers’ zapping counters it. This paper wishes to ascertain the audiences’... more
Broadcast television and its audiences live a paradoxical situation: on the one hand, channels still schedule according to the concept of flow; on the other hand, viewers’ zapping counters it. This paper wishes to ascertain the audiences’ practices regarding their fidelity to flow. The research tries to answer these questions: how many viewers watch the same channel during a long consecutive period? How many viewers watch a complete programme? Are there significant differences in zapping versus flow faithfulness according to sex, age, socio-demographic class and cable TV access? Is “companionship television” still a viewers’ consume practice? The research verifies the effectiveness of flow scheduling, which, while being an ideology and a scheduling and self-promotion practice, is not a practice of most viewers. The results show that flow faithfulness flow is a minority behaviour mainly of older people, women, lower classes and viewers without occupation.
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From September 2014 to November 2015, 30 Paralichthys orbignyanus specimens were obtained from Sepetiba Bay in the municipality of Rio de Janeiro, State of Rio de Janeiro, Brazil. The fishes were necropsied and cestode larvae were... more
From September 2014 to November 2015, 30 Paralichthys orbignyanus specimens were obtained from Sepetiba Bay in the municipality of Rio de Janeiro, State of Rio de Janeiro, Brazil. The fishes were necropsied and cestode larvae were recovered from the abdominal cavity, mesentery, and serosas of the stomach, intestine, spleen, liver, kidney and gonads. Nineteen fish were parasitized by a total of 90 trypanorhynch plerocerci. Based on morphological characters, these were identified as Pterobothrium crassicolle. The parasitism indices for P. crassicolle on P. orbignyanus, were 63.3% for prevalence, 4.7 for mean intensity, 3 for mean abundance and 1 to 18 for range of infection. These parasites were studied due to their importance during fish sanitary inspection, if one considers the harm that the repulsive aspect of infected fish may cause to consumers. This is the first record of P. crassicolle plerocerci parasitizing P. orbignyanus.
Research Interests: Brazil, Fish Diseases, Animals, Prevalence, Flounder, and 3 moreLarva, Cestode infections, and Cestoda
Purine nucleotide synthesis in protozoa takes place exclusively via the purine salvage pathway and S-adenosyl-l-homocysteine hydrolase (SAHH) is an important enzyme in the Plasmodium salvage pathway which is not present in erythrocytes.... more
Purine nucleotide synthesis in protozoa takes place exclusively via the purine salvage pathway and S-adenosyl-l-homocysteine hydrolase (SAHH) is an important enzyme in the Plasmodium salvage pathway which is not present in erythrocytes. Here, we describe the antimalarial effect of 2'3'-dialdehyde adenosine or oxidized adenosine (oADO), inhibitor of SAHH, on in vitro infection of human erythrocytes by P. falciparum. Treatment of infected erythrocytes with oADO inhibits parasite development and reinvasion of new cells. Erythrocytes pre-treated with oADO have a reduced susceptibility to invasion. Our results suggest that oADO interferes with one or more parasitic enzymes of the purine salvage pathway.
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Extracellular nucleotides can modulate the immunological response by activating purinergic receptors (P2Rs) on the cell surface of macrophages, dendritic, and other immune cells. In particular, the activation of P2X7R can induce release... more
Extracellular nucleotides can modulate the immunological response by activating purinergic receptors (P2Rs) on the cell surface of macrophages, dendritic, and other immune cells. In particular, the activation of P2X7R can induce release of cytokines and cell death as well as the uptake of large molecules through the cell membrane by a mechanism still poorly understood. Polyoxotungstate-1 (POM-1) has been proposed as a potent inhibitor of ecto-nucleotidases, enzymes that hydrolyze extracellular nucleotides, regulating the activity of P2Rs. However, the potential impact of POM-1 on P2Rs has not been evaluated. Here, we used fluorescent dye uptake, cytoplasmic free Ca(2+) concentration measurement, patch-clamp recordings, scanning electron microscopy, and quantification of inflammatory mediators to investigate the effects of POM-1 on P2Rs of murine macrophages. We observed that POM-1 blocks the P2YR-dependent cytoplasmic Ca(2+) increase and has partial effects on the cytoplasmic Ca(2+)...
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Esta investigación contribuye con una visión teórica y práctica de la nueva perspectiva de la gestión del valor del cliente (cvm) y sus implicaciones en los negocios. De hecho, el propósito de este trabajo es probar la influencia de la... more
Esta investigación contribuye con una visión teórica y práctica de la nueva perspectiva de la gestión del valor del cliente (cvm) y sus implicaciones en los negocios. De hecho, el propósito de este trabajo es probar la influencia de la cvm en los resultados financieros a través de la participación de mercado (ms), el margen bruto (gm) y el retorno sobre el capital (roe). Para ello, el enfoque utilizado es un estudio empírico con datos de 107 ejecutivos de ventas de uno de los bancos más grandes de Chile. Los resultados apoyan la hipótesis de que el cvm tendría una influencia positiva en la tasa de retención, así como en la optimización de los costos de adquisición de clientes y los ingresos generados a partir de estos. Este trabajo además establece la influencia que tiene la cvm en los resultados financieros de la compañía. Para evaluar los resultados de la organización, se han seleccionado indicadores financieros relevantes en la evaluación del desempeño financiero de una empresa. ...
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Obesity is an established risk factor for pancreatic ductal adenocarcinoma (PDA). Despite recent identification of metabolic alterations in this lethal malignancy, the metabolic dependencies of obesity-associated PDA remain unknown. Here... more
Obesity is an established risk factor for pancreatic ductal adenocarcinoma (PDA). Despite recent identification of metabolic alterations in this lethal malignancy, the metabolic dependencies of obesity-associated PDA remain unknown. Here we show that obesity-driven PDA exhibits accelerated growth and a striking transcriptional enrichment for pathways regulating nitrogen metabolism. We find that the mitochondrial form of arginase (ARG2), which hydrolyzes arginine into ornithine and urea, is induced upon obesity, and silencing or loss of ARG2 markedly suppresses PDA. In vivo infusion of (15)N-glutamine in obese mouse models of PDA demonstrates enhanced nitrogen flux into the urea cycle and infusion of (15)N-arginine shows that Arg2 loss causes significant ammonia accumulation that results from the shunting of arginine catabolism into alternative nitrogen repositories. Furthermore, analysis of PDA patient tumors indicates that ARG2 levels correlate with body mass index (BMI). The speci...
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The potential use of hybrid nanomaterials based on inorganic optically active nanoparticles known as quantum dots (QDs) and horseradish peroxidase (HRP) has been proposed by several authors as light-controllable nanocatalyzers, moreover,... more
The potential use of hybrid nanomaterials based on inorganic optically active nanoparticles known as quantum dots (QDs) and horseradish peroxidase (HRP) has been proposed by several authors as light-controllable nanocatalyzers, moreover, the immobilization within or over silica based supports represents an advantage over bulk-dispersed systems. However, the implications of the immobilization of such hybrid photoactivatable catalyzing systems have not been clarified with detail. Here, we present a thorough study of the functional photoactive efficiency and recycling of immobilized CdS QDs and HRP systems with different configurations, immobilized over silanized silica quartz crystal microbalance (QCM) sensors, allowing an accurate measure of the immobilized mass of each component and its correlation with the initial reaction rate of conversion of Amplex Red (AR) to resorufin. As well, the conversion efficiency is compared between the different systems and also to non-immobilized QD-H...
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Foetal midbrain progenitors have been shown to survive, give rise to different classes of dopamine neurons and integrate into the host brain alleviating Parkinsonian symptoms following transplantation in patients and animal models of the... more
Foetal midbrain progenitors have been shown to survive, give rise to different classes of dopamine neurons and integrate into the host brain alleviating Parkinsonian symptoms following transplantation in patients and animal models of the disease. Dopamine neuron subpopulations in the midbrain, namely A9 and A10, can be identified anatomically based on cell morphology and ascending axonal projections. G protein-gated inwardly rectifying potassium channel Girk2 and the calcium binding protein Calbindin are the two best available histochemical markers currently used to label (with some overlap) A9- and A10-like dopamine neuron subtypes, respectively, in tyrosine hydroxylase expressing neurons both in the midbrain and grafts. Both classes of dopamine neurons survive in grafts in the striatum and extend axonal projections to their normal dorsal and ventral striatal targets depending on phenotype. Nevertheless, grafts transplanted into the dorsal striatum, which is an A9 input nucleus, ar...
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Trypanosoma cruzi is the causative agent of Chagas disease and has a single mitochondrion, an organelle responsible for ATP production and the main site for the formation of reactive oxygen species (ROS). T. cruzi is an obligate... more
Trypanosoma cruzi is the causative agent of Chagas disease and has a single mitochondrion, an organelle responsible for ATP production and the main site for the formation of reactive oxygen species (ROS). T. cruzi is an obligate intracellular parasite with a complex life cycle that alternates between vertebrate and invertebrate hosts, therefore the development of survival strategies and morphogenetic adaptations to deal with the various environments is mandatory. Over the years our group has been studying the vector-parasite interactions using heme as a physiological oxidant molecule that triggered epimastigote proliferation however, the source of ROS induced by heme remained unknown. In the present study we demonstrate the involvement of heme in the parasite mitochondrial metabolism, decreasing oxygen consumption leading to increased mitochondrial ROS and membrane potential. First, we incubated epimastigotes with carbonyl cyanide p-(trifluoromethoxy) phenylhydrazone (FCCP), an uncoupler of oxidative phosphorylation, which led to decreased ROS formation and parasite proliferation, even in the presence of heme, correlating mitochondrial ROS and T. cruzi survival. This hypothesis was confirmed after the mitochondria-targeted antioxidant ((2-(2,2,6,6 Tetramethylpiperidin-1-oxyl-4-ylamino)-2-oxoethyl) triphenylphosphonium chloride (MitoTEMPO) decreased both heme-induced ROS and epimastigote proliferation. Furthermore, heme increased the percentage of tetramethylrhodamine methyl ester (TMRM) positive parasites tremendously-indicating the hyperpolarization and increase of potential of the mitochondrial membrane (ΔΨm). Assessing the mitochondrial functional metabolism, we observed that in comparison to untreated parasites, heme-treated epimastigotes decreased their oxygen consumption, and increased the complex II-III activity. These changes allowed the electron flow into the electron transport system, even though the complex IV (cytochrome c oxidase) activity decreased significantly, showing that heme-induced mitochondrial ROS appears to be a consequence of the enhanced mitochondrial physiological modulation. Finally, the parasites that were submitted to high concentrations of heme presented no alterations in the ultrastructure. Consequently, our results suggest that heme released by the insect vector after the blood meal, modify epimastigote mitochondrial physiology to increase ROS as a metabolic mechanism to maintain epimastigote survival and proliferation.
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En el presente trabajo se analiza el proceso de configuración territorial de Mendoza, Argentina, representativo de otros pertenecientes a tierras secas de América Latina, en el marco de la concepción de las "nuevas periferias"... more
En el presente trabajo se analiza el proceso de configuración territorial de Mendoza, Argentina, representativo de otros pertenecientes a tierras secas de América Latina, en el marco de la concepción de las "nuevas periferias" asociadas a la reestructuración de las economías. La fragmentación territorial actual sería el producto de una misma lógica que, mientras concentra recursos, población y poder en una pequeña porción del territorio -los oasis irrigados-, lo hace a costa del despojo o agotamiento de recursos y grupos sociales minoritarios de los espacios desérticos. Éstos no tienen cabida en el imaginario local, no forman parte de la identidad de su sociedad y constituyen verdaderos "espacios invisibles" que se integran al modelo desde su subordinación, su vulnerabilidad, y se aproximan progresivamente a la exclusión.
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Mammalian X-linked gene expression is highly regulated as female cells contain two and male one X chromosome (X). To adjust the X gene dosage between genders, female mouse preimplantation embryos undergo an imprinted form of X chromosome... more
Mammalian X-linked gene expression is highly regulated as female cells contain two and male one X chromosome (X). To adjust the X gene dosage between genders, female mouse preimplantation embryos undergo an imprinted form of X chromosome inactivation (iXCI) that requires both Rlim (also known as Rnf12) and the long non-coding RNA Xist. Moreover, it is thought that gene expression from the single active X is upregulated to correct for bi-allelic autosomal (A) gene expression. We have combined mouse genetics with RNA-seq on single mouse embryos to investigate functions of Rlim on the temporal regulation of iXCI and Xist. Our results reveal crucial roles of Rlim for the maintenance of high Xist RNA levels, Xist clouds and X-silencing in female embryos at blastocyst stages, while initial Xist expression appears Rlim-independent. We find further that X/A upregulation is initiated in early male and female preimplantation embryos.