53 research outputs found

    Pharmacogenetics, tobacco, alcohol and its effect on the risk development cancer

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    Indexación: Scopus; Scielo.Cancer is the second leading cause of death in the world, causing 8.8 million deaths in 2015 according to the World Health Organization (WHO). Risk factors for cancer include smoking and alcohol consumption. In Chile, 33.6% of the population and 21.2% of young people smokes. Alcohol consumption in the Chilean population is 74.5% and 12.2% in young people. Among the physiological factors that influence the development of cancer, the genetic factor plays a relevant role. It has been shown that the presence of genetic polymorphisms that alter the ability of the body to eliminate contaminants increase the risk of developing cancer. The same applies to polymorphisms that prevent DNA repair due to damage caused by environmental pollutants such as cigarette smoke. The objective of this review is to analyze the state of the art of the relationship between pharmacogenetics, smoking, and alcohol consumption as risk factors for the development of cancer. In conclusion, the results suggest that the presence of polymorphisms that alter the function of biotransformation enzymes phase I (CYP1A1, CYP1E1) and phase II (GST), as well as polymorphisms in DNA repair enzymes (ERCC1 / ERCC2), increase the risk of cancer induced by smoking and alcohol consumption. This association is important considering that smoking and drinking alcohol are highly prevalent among the Chilean population. © 2018, Sociedad Chilena de Pediatria. All rights reserved.Cancer is the second leading cause of death in the world, causing 8.8 million deaths in 2015 according to the World Health Organization (WHO). Risk factors for cancer include smoking and alcohol con sumption. In Chile, 33.6% of the population and 21.2% of young people smokes. Alcohol consump tion in the Chilean population is 74.5% and 12.2% in young people. Among the physiological factors that influence the development of cancer, the genetic factor plays a relevant role. It has been shown that the presence of genetic polymorphisms that alter the ability of the body to eliminate contami nants increase the risk of developing cancer. The same applies to polymorphisms that prevent DNA repair due to damage caused by environmental pollutants such as cigarette smoke. The objective of this review is to analyze the state of the art of the relationship between pharmacogenetics, smoking, and alcohol consumption as risk factors for the development of cancer. In conclusion, the results suggest that the presence of polymorphisms that alter the function of biotransformation enzymes phase I (CYP1A1, CYP1E1) and phase II (GST), as well as polymorphisms in DNA repair enzymes (ERCC1 / ERCC2), increase the risk of cancer induced by smoking and alcohol consumption. This association is important considering that smoking and drinking alcohol are highly prevalent among the Chilean population.https://scielo.conicyt.cl/scielo.php?script=sci_arttext&pid=S0370-41062018005000709&lng=en&nrm=iso&tlng=e

    Density functional theory based screening of ternary alkali-transition metal borohydrides: A computational material design project

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    The dissociation of molecules, even the most simple hydrogen molecule, cannot be described accurately within density functional theory because none of the currently available functionals accounts for strong on-site correlation. This problem led to a discussion of properties that the local Kohn-Sham potential has to satisfy in order to correctly describe strongly correlated systems. We derive an analytic expression for the nontrivial form of the Kohn-Sham potential in between the two fragments for the dissociation of a single bond. We show that the numerical calculations for a one-dimensional two-electron model system indeed approach and reach this limit. It is shown that the functional form of the potential is universal, i.e., independent of the details of the two fragments.We acknowledge funding by the Spanish MEC (Grant No. FIS2007-65702-C02-01), “Grupos Consolidados UPV/EHU del Gobierno Vasco” (Grant No. IT-319-07), and the European Community through e-I3 ETSF project (Grant Agreement No. 211956).Peer reviewe

    Density functional theory based screening of ternary alkali-transition metal borohydrides: A computational material design project

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    Insect pathogens as biological control agents: back to the future

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    The development and use of entomopathogens as classical, conservation and augmentative biological control agents have included a number of successes and some setbacks in the past 15 years. In this forum paper we present current information on development, use and future directions of insect-specific viruses, bacteria, fungi and nematodes as components of integrated pest management strategies for control of arthropod pests of crops, forests, urban habitats, and insects of medical and veterinary importance. Insect pathogenic viruses are a fruitful source of MCAs, particularly for the control of lepidopteran pests. Most research is focused on the baculoviruses, important pathogens of some globally important pests for which control has become difficult due to either pesticide resistance or pressure to reduce pesticide residues. Baculoviruses are accepted as safe, readily mass produced, highly pathogenic and easily formulated and applied control agents. New baculovirus products are appearing in many countries and gaining an increased market share. However, the absence of a practical in vitro mass production system, generally higher production costs, limited post application persistence, slow rate of kill and high host specificity currently contribute to restricted use in pest control. Overcoming these limitations are key research areas for which progress could open up use of insect viruses to much larger markets. A small number of entomopathogenic bacteria have been commercially developed for control of insect pests. These include several Bacillus thuringiensis sub-species, Lysinibacillus (Bacillus) sphaericus, Paenibacillus spp. and Serratia entomophila. B. thuringiensis sub-species kurstaki is the most widely used for control of pest insects of crops and forests, and B. thuringiensis sub-species israelensis and L. sphaericus are the primary pathogens used for medically important pests including dipteran vectors,. These pathogens combine the advantages of chemical pesticides and microbial control agents (MCAs): they are fast acting, easy to produce at a relatively low cost, easy to formulate, have a long shelf life and allow delivery using conventional application equipment and systemics (i.e. in transgenic plants). Unlike broad spectrum chemical pesticides, B. thuringiensis toxins are selective and negative environmental impact is very limited. Of the several commercially produced MCAs, B. thuringiensis (Bt) has more than 50% of market share. Extensive research, particularly on the molecular mode of action of Bt toxins, has been conducted over the past two decades. The Bt genes used in insect-resistant transgenic crops belong to the Cry and vegetative insecticidal protein families of toxins. Bt has been highly efficacious in pest management of corn and cotton, drastically reducing the amount of broad spectrum chemical insecticides used while being safe for consumers and non-target organisms. Despite successes, the adoption of Bt crops has not been without controversy. Although there is a lack of scientific evidence regarding their detrimental effects, this controversy has created the widespread perception in some quarters that Bt crops are dangerous for the environment. In addition to discovery of more efficacious isolates and toxins, an increase in the use of Bt products and transgenes will rely on innovations in formulation, better delivery systems and ultimately, wider public acceptance of transgenic plants expressing insect-specific Bt toxins. Fungi are ubiquitous natural entomopathogens that often cause epizootics in host insects and possess many desirable traits that favor their development as MCAs. Presently, commercialized microbial pesticides based on entomopathogenic fungi largely occupy niche markets. A variety of molecular tools and technologies have recently allowed reclassification of numerous species based on phylogeny, as well as matching anamorphs (asexual forms) and teleomorphs (sexual forms) of several entomopathogenic taxa in the Phylum Ascomycota. Although these fungi have been traditionally regarded exclusively as pathogens of arthropods, recent studies have demonstrated that they occupy a great diversity of ecological niches. Entomopathogenic fungi are now known to be plant endophytes, plant disease antagonists, rhizosphere colonizers, and plant growth promoters. These newly understood attributes provide possibilities to use fungi in multiple roles. In addition to arthropod pest control, some fungal species could simultaneously suppress plant pathogens and plant parasitic nematodes as well as promote plant growth. A greater understanding of fungal ecology is needed to define their roles in nature and evaluate their limitations in biological control. More efficient mass production, formulation and delivery systems must be devised to supply an ever increasing market. More testing under field conditions is required to identify effects of biotic and abiotic factors on efficacy and persistence. Lastly, greater attention must be paid to their use within integrated pest management programs; in particular, strategies that incorporate fungi in combination with arthropod predators and parasitoids need to be defined to ensure compatibility and maximize efficacy. Entomopathogenic nematodes (EPNs) in the genera Steinernema and Heterorhabditis are potent MCAs. Substantial progress in research and application of EPNs has been made in the past decade. The number of target pests shown to be susceptible to EPNs has continued to increase. Advancements in this regard primarily have been made in soil habitats where EPNs are shielded from environmental extremes, but progress has also been made in use of nematodes in above-ground habitats owing to the development of improved protective formulations. Progress has also resulted from advancements in nematode production technology using both in vivo and in vitro systems; novel application methods such as distribution of infected host cadavers; and nematode strain improvement via enhancement and stabilization of beneficial traits. Innovative research has also yielded insights into the fundamentals of EPN biology including major advances in genomics, nematode-bacterial symbiont interactions, ecological relationships, and foraging behavior. Additional research is needed to leverage these basic findings toward direct improvements in microbial control

    An analysis of the electrocardiogram QT interval

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    No reports testing the efficacy of the use of the QT/RR ratio <1/2 for detecting a normal QTc interval were found in the literature. The objective of the present study was to determine if a QT/RR ratio <=1/2 can be considered to be equal to the normal QTc and to compare the QT and QTc measured and calculated clinically and by a computerized electrocardiograph. Ratios (140 QT/RR) of 28 successive electrocardiograms obtained from 28 consecutive patients in a tertiary level teaching hospital were analyzed clinically by 5 independent observers and by a computerized electrocardiograph. The QT/RR ratio provided 56% sensitivity and 78% specificity, with an area under the receiver operator characteristic curve of 75.8% (95%CI: 0.68 to 0.84). The divergence in QT and QTc interval measurements between clinical and computerized evaluation were 0.01 ± 0.03 s (95%CI: 0.04-0.02) and 0.01 ± 0.04 s (95%CI: -0.05-0.03), respectively. The QT and QTc values measured clinically and by a computerized electrocardiograph were similar. The QT/RR ratio <=1/2 was not a satisfactory index for QTc evaluation because it could not predict a normal QTc value

    Interacciones neuroinmunológicas en el ictus

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    Resumen: Introducción: El ictus es una de las principales causas de mortalidad en el mundo y debido al incremento en la expectativa de vida su incidencia va en aumento; sin embargo, el desarrollo de nuevos medicamentos con utilidad clínica ha sido prácticamente nulo, por lo que hasta la fecha el tratamiento de estos pacientes es muy limitado. Desarrollo: La evidencia básica y clínica en el área señala que tras un infarto cerebral se producen una serie de cambios neuroquímicos, entre los que se encuentran: la depleción energética, la producción de radicales libres, la acumulación de calcio, la desregulación de neurotransmisores, la excitotoxicidad, y de manera tardía, la activación del sistema inmune caracterizada como inflamación. Esta respuesta del sistema inmunológico ha mostrado ser un evento central en la progresión de la patología, en el que destaca la participación de las citocinas proinflamatorias como TNF, que aumentan el daño por excitotoxicidad y por acumulación de calcio, favorecen la formación de radicales libres y en general promueven la muerte celular. Por otro lado, algunas citocinas antiinflamatorias como IL-10 e IL-4 han mostrado tener efectos neuroprotectores e incluso favorecen la recuperación de sinapsis y la neurogénesis, haciendo de la modulación de la respuesta inmunológica un área con mucho potencial terapéutico. Conclusiones: El entendimiento de las relaciones entre el sistema inmunológico y el sistema nervioso no solo nos permite entender con mayor profundidad el fenómeno del ictus, sino que también nos ofrece un nuevo arsenal de estrategias diagnósticas, pronósticas y terapéuticas que podrían mejorar la calidad de vida de las personas aquejadas por esta terrible enfermedad. Abstract: Introduction: Stroke is one of the leading causes of death in the world; its incidence is increasing due to increased life expectancy. However, treatment options for these patients are limited since no clinically effective drugs have been developed to date. Development: According to clinical evidence, a number of neurochemical changes take place after stroke, including energy depletion, increased free radical synthesis, calcium accumulation, neurotransmitter imbalance, excitotoxicity, and, at a later stage, immune system activation leading to inflammation.Immune response has been shown to be a major factor in disease progression. The release of proinflammatory cytokines such as TNF increase brain damage secondary to excitotoxicity and calcium accumulation, and promote free radical synthesis and cell death through various mechanisms. On the other hand, certain anti-inflammatory cytokines, such as IL-10 and IL-4, have been shown to have a neuroprotective effect and even promote neurogenesis and synapse remodeling, which makes immune modulation a promising treatment approach. Conclusions: Understanding the relationship between the immune system and the nervous system not only deepens our knowledge of stroke but also provides new diagnostic, prognostic, and therapeutic strategies that may increase the quality of life of stroke patients. Palabras clave: Ictus, Inflamación, Penumbra, Neurogénesis, Neuroprotección, Keywords: Stroke, Inflammation, Penumbra, Neurogenesis, Neuroprotectio

    Neuroimmunological interactions in stroke

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    Introduction: Stroke is one of the leading causes of death in the world; its incidence is increasing due to increased life expectancy. However, treatment options for these patients are limited since no clinically effective drugs have been developed to date. Development: According to clinical evidence, a number of neurochemical changes take place after stroke, including energy depletion, increased free radical synthesis, calcium accumulation, neurotransmitter imbalance, excitotoxicity, and, at a later stage, immune system activation leading to inflammation.Immune response has been shown to be a major factor in disease progression. The release of proinflammatory cytokines such as TNF increase brain damage secondary to excitotoxicity and calcium accumulation, and promote free radical synthesis and cell death through various mechanisms. On the other hand, certain anti-inflammatory cytokines, such as IL-10 and IL-4, have been shown to have a neuroprotective effect and even promote neurogenesis and synapse remodelling, which makes immune modulation a promising treatment approach. Conclusions: Understanding the relationship between the immune system and the nervous system not only deepens our knowledge of stroke but also provides new diagnostic, prognostic, and therapeutic strategies that may increase the quality of life of stroke patients. Resumen: Introducción: El ictus es una de las principales causas de mortalidad en el mundo y debido al incremento en la expectativa de vida su incidencia va en aumento; sin embargo, el desarrollo de nuevos medicamentos con utilidad clínica ha sido prácticamente nulo, por lo que hasta la fecha el tratamiento de estos pacientes es muy limitado. Desarrollo: La evidencia básica y clínica en el área señala que tras un infarto cerebral se producen una serie de cambios neuroquímicos, entre los que se encuentran: la depleción energética, la producción de radicales libres, la acumulación de calcio, la desregulación de neurotransmisores, la excitotoxicidad, y de manera tardía, la activación del sistema inmune caracterizada como inflamación. Esta respuesta del sistema inmunológico ha mostrado ser un evento central en la progresión de la patología, en el que destaca la participación de las citocinas proinflamatorias como TNF, que aumentan el daño por excitotoxicidad y por acumulación de calcio, favorecen la formación de radicales libres y en general promueven la muerte celular. Por otro lado, algunas citocinas antiinflamatorias como IL-10 e IL-4 han mostrado tener efectos neuroprotectores e incluso favorecen la recuperación de sinapsis y la neurogénesis, haciendo de la modulación de la respuesta inmunológica un área con mucho potencial terapéutico. Conclusiones: El entendimiento de las relaciones entre el sistema inmunológico y el sistema nervioso no solo nos permite entender con mayor profundidad el fenómeno del ictus, sino que también nos ofrece un nuevo arsenal de estrategias diagnósticas, pronósticas y terapéuticas que podrían mejorar la calidad de vida de las personas aquejadas por esta terrible enfermedad. Keywords: Stroke, Inflammation, Penumbra, Neurogenesis, Neuroprotection, Palabras clave: Ictus, Inflamación, Penumbra, Neurogénesis, Neuroprotecció
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