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An AISI 304 stainless steel laminar electrode without oxidative treatment was investigated for the potentiometric titration of hydrochloric acid with sodium hydroxide. The proposed electrode was obtained from metalworking cuttings. Scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray fluorescence spectroscopy and X-ray diffraction were used to study the surface morphology and chemical composition of the electrode. The electrode showed a sensitivity of 59.18 ± 0.37 mV/pH, which was reproducible under intermediate conditions. Potentiometric titration showed a curve with deviations from pH 9.5 with respect to the glass electrode. However, this did not affect the quantification as the jumps of the curves coincided. The endpoint was 9.25 mL for both electrodes and the hydrochloric acid concentration was 0.0845 mol/L, with a deviation of 0.0004 mol/L from the standard concentration of 0.0841 mol/L. The nonartificially oxidised electrode did not show any crystalline oxide phases, whereas after oxidation it showed semicrystalline phases of iron and chromium oxides and increased the crystallinity of the steel. Despite the low content of surface oxides, stainless steel electrodes can give a Nernstian response to pH, depending on the surface characteristics of the material. This leads to the need to calibrate any electrode prior to oxidative treatment to rule out a Nernstian response without surface modification.
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Hippocampal-dependent memories emerge late during postnatal development, aligning with hippocampal maturation. During sleep, the two-stage memory formation model states that through hippocampal-neocortical interactions, cortical slow-oscillations (SO), thalamocortical Spindles, and hippocampal sharp-wave ripples (SWR) are synchronized, allowing for the consolidation of hippocampal-dependent memories. However, evidence supporting this hypothesis during development is still lacking. Therefore, we performed successive object-in-place tests during a window of memory emergence and recorded in vivo the occurrence of SO, Spindles, and SWR during sleep, immediately after the memory encoding stage of the task. We found that hippocampal-dependent memory emerges at the end of the 4th postnatal week independently of task overtraining. Furthermore, we observed that those animals with better performance in the memory task had increased Spindle density and duration and lower density of SWR. Moreover, we observed changes in the SO-Spindle and Spindle-SWR temporal-coupling during this developmental period. Our results provide new evidence for the onset of hippocampal-dependent memory and its relationship to the oscillatory phenomenon occurring during sleep that helps us understand how memory consolidation models fit into the early stages of postnatal development.
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Several previous studies on targeted food items using carbon and nitrogen stable isotope ratios in Brazil have revealed that many of the items investigated are adulterated; mislabeled or even fraud. Here, we present the first Brazilian isotopic baseline assessment that can be used not only in future forensic cases involving food authenticity, but also in human forensic anthropology studies. The δ13C and δ15N were determined in 1245 food items and 374 beverages; most of them made in Brazil. The average δ13C and δ15N of C3 plants were -26.7 ± 1.5‱, and 3.9 ± 3.9‱, respectively, while the average δ13C and δ15N of C4 plants were -11.5 ± 0.8‱ and 4.6 ± 2.6‱, respectively. The δ13C and δ15N of plant-based processed foods were -21.8 ± 4.8‱ and 3.9 ± 2.7‱, respectively. The average δ13C and δ15N of meat, including beef, poultry, pork and lamb were -16.6 ± 4.7‱, and 5.2 ± 2.6‱, respectively, while the δ13C and δ15N of animal-based processed foods were -17.9 ± 3.3‱ and 3.3 ± 3.5‱, respectively. The average δ13C of beverages, including beer and wine was -22.5 ± 3.1‱. We verified that C-C4 constitutes a large proportion of fresh meat, dairy products, as well as animal and plant-based processed foods. The reasons behind this high proportion will be addressed in this study.
Assuntos
Isótopos de Carbono/análise , Isótopos de Nitrogênio/análise , Animais , Bebidas/análise , Brasil , Bovinos , Laticínios/análise , Aves Domésticas , Ovinos , Vinho/análiseRESUMO
Smut disease caused by the fungal pathogen Thecaphora frezii Carranza & Lindquist is threatening the peanut production in Argentina. Fungicides commonly used in the peanut crop have shown little or no effect controlling the disease, making it a priority to obtain peanut varieties resistant to smut. In this study, recombinant inbred lines (RILs) were developed from three crosses between three susceptible peanut elite cultivars (Arachis hypogaea L. subsp. hypogaea) and two resistant landraces (Arachis hypogaea L. subsp. fastigiata Waldron). Parents and RILs were evaluated under high inoculum pressure (12000 teliospores g-1 of soil) over three years. Disease resistance parameters showed a broad range of variation with incidence mean values ranging from 1.0 to 35.0% and disease severity index ranging from 0.01 to 0.30. Average heritability (h2) estimates of 0.61 to 0.73 indicated that resistance in the RILs was heritable, with several lines (4 to 7 from each cross) showing a high degree of resistance and stability over three years. Evidence of genetic transfer between genetically distinguishable germplasm (introgression in a broad sense) was further supported by simple-sequence repeats (SSRs) and Insertion/Deletion (InDel) marker genotyping. This is the first report of smut genetic resistance identified in peanut landraces and its introgression into elite peanut cultivars.
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Arachis/genética , Basidiomycota/patogenicidade , Resistência à Doença/genética , Doenças das Plantas/genética , Imunidade Vegetal/genética , Alelos , Arachis/imunologia , Arachis/microbiologia , Basidiomycota/crescimento & desenvolvimento , Cruzamentos Genéticos , Marcadores Genéticos , Genótipo , Mutação INDEL , Repetições de Microssatélites , Melhoramento Vegetal/métodos , Doenças das Plantas/imunologia , Característica Quantitativa HerdávelRESUMO
Studies conducted in rodents subjected to chronic stress and some observations in humans after psychosocial stress, have allowed to establish a link between stress and the susceptibility to many complex diseases, including mood disorders. The studies in rodents have revealed that chronic exposure to stress negatively affects synaptic plasticity by triggering changes in the production of trophic factors, subunit levels of glutamate ionotropic receptors, neuron morphology, and neurogenesis in the adult hippocampus. These modifications may account for the impairment in learning and memory processes observed in chronically stressed animals. It is plausible then, that stress modifies the interplay between signal transduction cascades and gene expression regulation in the hippocampus, therefore leading to altered neuroplasticity and functioning of neural circuits. Considering that miRNAs play an important role in post-transcriptional-regulation of gene expression and participate in several hippocampus-dependent functions; we evaluated the consequences of chronic stress on the expression of miRNAs in dorsal (anterior) portion of the hippocampus, which participates in memory formation in rodents. Here, we show that male rats exposed to daily restraint stress (2.5 h/day) during 7 and 14 days display a differential profile of miRNA levels in dorsal hippocampus and remarkably, we found that some of these miRNAs belong to the miR-379-410 cluster. We confirmed a rise in miR-92a and miR-485 levels after 14 days of stress by qPCR, an effect that was not mimicked by chronic administration of corticosterone (14 days). Our in silico study identified the top-10 biological functions influenced by miR-92a, nine of which were shared with miR-485: Nervous system development and function, Tissue development, Behavior, Embryonic development, Organ development, Organismal development, Organismal survival, Tissue morphology, and Organ morphology. Furthermore, our in silico study provided a landscape of potential miRNA-92a and miR-485 targets, along with relevant canonical pathways related to axonal guidance signaling and cAMP signaling, which may influence the functioning of several neuroplastic substrates in dorsal hippocampus. Additionally, the combined effect of miR-92a and miR-485 on transcription factors, along with histone-modifying enzymes, may have a functional relevance by producing changes in gene regulatory networks that modify the neuroplastic capacity of the adult dorsal hippocampus under stress.
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A single stress exposure facilitates memory formation through neuroplastic processes that reshape excitatory synapses in the hippocampus, probably requiring changes in extracellular matrix components. We tested the hypothesis that matrix metalloproteinase 9 (MMP-9), an enzyme that degrades components of extracellular matrix and synaptic proteins such as ß-dystroglycan (ß-DG43), changes their activity and distribution in rat hippocampus during the acute stress response. After 2.5 h of restraint stress, we found (i) increased MMP-9 levels and potential activity in whole hippocampal extracts, accompanied by ß-DG43 cleavage, and (ii) a significant enhancement of MMP-9 immunoreactivity in dendritic fields such as stratum radiatum and the molecular layer of hippocampus. After 24 h of stress, we found that (i) MMP-9 net activity rises at somatic field, i.e., stratum pyramidale and granule cell layers, and also at synaptic field, mainly stratum radiatum and the molecular layer of hippocampus, and (ii) hippocampal synaptoneurosome fractions are enriched with MMP-9, without variation of its potential enzymatic activity, in accordance with the constant level of cleaved ß-DG43. These findings indicate that stress triggers a peculiar timing response in the MMP-9 levels, net activity, and subcellular distribution in the hippocampus, suggesting its involvement in the processing of substrates during the stress response.
Assuntos
Hipocampo/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Plasticidade Neuronal/fisiologia , Sinapses/metabolismo , Potenciais de Ação/fisiologia , Animais , Dendritos/metabolismo , Masculino , Neurônios/metabolismo , Ratos Sprague-Dawley , Estresse Fisiológico/fisiologia , Fatores de TempoRESUMO
Low- and middle-income countries (LMIC) lack the research infrastructure and capacity to conduct rigorous substance abuse and mental health effectiveness clinical trials to guide clinical practice. A partnership between the Florida Node Alliance of the United States National Drug Abuse Treatment Clinical Trials Network and the National Institute of Psychiatry in Mexico was established in 2011 to improve substance abuse practice in Mexico. The purpose of this partnership was to develop a Mexican national clinical trials network of substance abuse researchers and providers capable of implementing effectiveness randomized clinical trials in community-based settings. A technology transfer model was implemented and ran from 2011–2013. The Florida Node Alliance shared the “know how” for the development of the research infrastructure to implement randomized clinical trials in community programs through core and specific training modules, role-specific coaching, pairings, modeling, monitoring, and feedback. The technology transfer process was bi-directional in nature in that it was informed by feedback on feasibility and cultural appropriateness for the context in which practices were implemented. The Institute, in turn, led the effort to create the national network of researchers and practitioners in Mexico and the implementation of the first trial. A collaborative model of technology transfer was useful in creating a Mexican researcher-provider network that is capable of changing national practice in substance abuse research and treatment. Key considerations for transnational technology transfer are presented.
Los países de ingresos bajos o medios (PIBM) carecen de una infraestructura de investigación y de la capacidad para llevar a cabo investigaciones clínicas rigurosas sobre la eficacia del tratamiento de la drogadicción y los problemas de salud mental que orienten la práctica clínica. Se estableció una asociación entre la Florida Node Alliance de la National Drug Abuse Treatment Clinical Trials Network de los Estados Unidos y el Instituto Nacional de Psiquiatría de México con objeto de mejorar la práctica en materia de tratamiento de la drogadicción en México. La finalidad de esta asociación fue la de crear una red nacional mexicana de investigaciones clínicas constituida por investigadores y proveedores de tratamiento de la drogadicción capaces de ejecutar ensayos clínicos aleatorizados de eficacia en entornos comunitarios. Se implantó un modelo de transferencia de tecnologías. La Florida Node Alliance compartió el el conocimiento y la experiencia para la creación de la infraestructura de investigación con objeto de ejecutar investigaciones clínicas aleatorizadas en programas comunitarios, por medio de módulos de capacitación común y específica, entrenamiento en funciones específicas, emparejamientos, modelado, vigilancia y retroalimentación. El proceso de transferencia de tecnología fue de tipo bidireccional en cuanto se basó en la retroalimentación sobre la viabilidad y la adecuación cultural para el contexto en el que se llevaron a cabo las prácticas. El Instituto, a su vez, lideró la iniciativa para crear la red nacional de investigadores y profesionales de México y llevar a cabo el primer ensayo. Un modelo colaborativo de transferencia de tecnología resultó útil para la creación de una red mexicana de investigadores y proveedores de tratamiento capaz de cambiar las prácticas nacionales de investigación y tratamiento en materia de drogadicción. Se exponen las consideraciones clave para la transferencia transnacional de tecnología.
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Transferência de Tecnologia , Ensaios Clínicos como Assunto , Prática Clínica Baseada em Evidências , Transtornos Relacionados ao Uso de Substâncias , Saúde Mental , Transferência de Tecnologia , Ensaios Clínicos como Assunto , Prática Clínica Baseada em Evidências , Redes de Informação de Ciência e Tecnologia , Transtornos Relacionados ao Uso de Substâncias , Saúde Mental , Pesquisa sobre Serviços de Saúde , Métodos , México , Redes de Informação de Ciência e Tecnologia , Pesquisa sobre Serviços de SaúdeRESUMO
Low- and middle-income countries (LMIC) lack the research infrastructure and capacity to conduct rigorous substance abuse and mental health effectiveness clinical trials to guide clinical practice. A partnership between the Florida Node Alliance of the United States National Drug Abuse Treatment Clinical Trials Network and the National Institute of Psychiatry in Mexico was established in 2011 to improve substance abuse practice in Mexico. The purpose of this partnership was to develop a Mexican national clinical trials network of substance abuse researchers and providers capable of implementing effectiveness randomized clinical trials in community-based settings. A technology transfer model was implemented and ran from 2011-2013. The Florida Node Alliance shared the "know how" for the development of the research infrastructure to implement randomized clinical trials in community programs through core and specific training modules, role-specific coaching, pairings, modeling, monitoring, and feedback. The technology transfer process was bi-directional in nature in that it was informed by feedback on feasibility and cultural appropriateness for the context in which practices were implemented. The Institute, in turn, led the effort to create the national network of researchers and practitioners in Mexico and the implementation of the first trial. A collaborative model of technology transfer was useful in creating a Mexican researcher-provider network that is capable of changing national practice in substance abuse research and treatment. Key considerations for transnational technology transfer are presented.
Los países de ingresos bajos o medios (PIBM) carecen de una infraestructura de investigación y de la capacidad para llevar a cabo investigaciones clínicas rigurosas sobre la eficacia del tratamiento de la drogadicción y los problemas de salud mental que orienten la práctica clínica. Se estableció una asociación entre la Florida Node Alliance de la National Drug Abuse Treatment Clinical Trials Network de los Estados Unidos y el Instituto Nacional de Psiquiatría de México con objeto de mejorar la práctica en materia de tratamiento de la drogadicción en México. La finalidad de esta asociación fue la de crear una red nacional mexicana de investigaciones clínicas constituida por investigadores y proveedores de tratamiento de la drogadicción capaces de ejecutar ensayos clínicos aleatorizados de eficacia en entornos comunitarios. Se implantó un modelo de transferencia de tecnologías. La Florida Node Alliance compartió el el conocimiento y la experiencia para la creación de la infraestructura de investigación con objeto de ejecutar investigaciones clínicas aleatorizadas en programas comunitarios, por medio de módulos de capacitación común y específica, entrenamiento en funciones específicas, emparejamientos, modelado, vigilancia y retroalimentación. El proceso de transferencia de tecnología fue de tipo bidireccional en cuanto se basó en la retroalimentación sobre la viabilidad y la adecuación cultural para el contexto en el que se llevaron a cabo las prácticas. El Instituto, a su vez, lideró la iniciativa para crear la red nacional de investigadores y profesionales de México y llevar a cabo el primer ensayo. Un modelo colaborativo de transferencia de tecnología resultó útil para la creación de una red mexicana de investigadores y proveedores de tratamiento capaz de cambiar las prácticas nacionales de investigación y tratamiento en materia de drogadicción. Se exponen las consideraciones clave para la transferencia transnacional de tecnología.
Assuntos
Saúde Mental , Tecnologia Biomédica , Medicina do Vício/organização & administração , MéxicoRESUMO
Low- and middle-income countries (LMIC) lack the research infrastructure and capacity to conduct rigorous substance abuse and mental health effectiveness clinical trials to guide clinical practice. A partnership between the Florida Node Alliance of the United States National Drug Abuse Treatment Clinical Trials Network and the National Institute of Psychiatry in Mexico was established in 2011 to improve substance abuse practice in Mexico. The purpose of this partnership was to develop a Mexican national clinical trials network of substance abuse researchers and providers capable of implementing effectiveness randomized clinical trials in community-based settings. A technology transfer model was implemented and ran from 2011-2013. The Florida Node Alliance shared the "know how" for the development of the research infrastructure to implement randomized clinical trials in community programs through core and specific training modules, role-specific coaching, pairings, modeling, monitoring, and feedback. The technology transfer process was bi-directional in nature in that it was informed by feedback on feasibility and cultural appropriateness for the context in which practices were implemented. The Institute, in turn, led the effort to create the national network of researchers and practitioners in Mexico and the implementation of the first trial. A collaborative model of technology transfer was useful in creating a Mexican researcher-provider network that is capable of changing national practice in substance abuse research and treatment. Key considerations for transnational technology transfer are presented.
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Saúde Mental , Transtornos Relacionados ao Uso de Substâncias , Transferência de Tecnologia , Ensaios Clínicos como Assunto , Comportamento Cooperativo , Humanos , México , Transtornos Relacionados ao Uso de Substâncias/terapiaRESUMO
El cáncer de laringe representa un 20%-25% de los carcinomas de cabeza y cuello. Actualmente su tratamiento incluye diversas modalidades, desde cirugía para enfermedad localizada hasta esquemas concurrentes de quimioterapia y radioterapia para estadios avanzados. Evaluar los resultados del tratamiento del carcinoma laríngeo en nuestra institución en el período 2000-2009; por lo que se realizó un estudio retrospectivo analítico basado en las historias clínicas de pacientes con diagnóstico histopatológico de carcinoma laríngeo, en estadios precoces y avanzados no metastásicos. El objetivo primario del estudio es evaluar la supervivencia global, según el estadiaje y/o las modalidades terapéuticas. Los objetivos secundarios incluyen supervivencia libre de enfermedad y supervivencia libre de laringectomía. Un total de 187 pacientes, la sobrevida global fue significativamente mayor en estadios precoces comparado a estadios avanzados (P=0,023). La sobrevida global en estadios avanzados no presentó diferencias estadísticamente significativas independientemente de la modalidad de tratamiento aplicado. La sobrevida libre de laringectomía y libre de enfermedad muestra una tendencia preliminar a favor del tratamiento concurrente definitivo en estadios avanzados. La sobrevida global y libre de enfermedad en estadios precoces no presentó variación de acuerdo a la modalidad del tratamiento definitivo (P=0,086). La radioterapia ofrece una eficacia comparable a la cirugía en estadios precoces, el tratamiento multimodal de estadios avanzados permite una mayor sobrevida libre de laringectomía y libre de enfermedad sin impacto aparente en la sobrevida global en relación con la cirugía radical.
The laryngeal cancer accounts for 20%- 25% of all the head and neck carcinomas. The current treatment includes various forms ranging from surgery for localized disease to concurrent schemes chemotherapy and radiotherapy for the advanced stages. The purpose of this study is to evaluate the results of the treatment of laryngeal carcinoma at our institution in the period 2000-2009. For what was done a retrospective study based on medical records of patients with histopathological diagnosis of laryngeal carcinoma, stage early and in advanced non-metastatic. The primary objective is to evaluate overall survival, according to the staging and or therapeutic modalities we used. The secondary end points included disease free survival, laringectomy free survival. For a total of 187 patients, the overall survival was significantly higher in early stages compared to advanced stages (P=0.023). The global survival in advanced stages did not differ statistically significant regardless of the type of treatment we applied. The free laringectomy survival and the disease free survival show atrend in favor of the preliminary final concurrent treatment in the advanced stages. The overall survival and disease free survival in early stages did not present variation according to the definitive treatment modality (P= 0.086). Radiotherapy offers comparable efficacy to surgery in early stages, multimodal treatment for advanced stages allows greater laringectomy free survival and disease free survival without apparent impact on overall free survival in relation to the radical surgery.