42 research outputs found
High fat diet intake during pre and periadolescence impairs learning of a conditioned place preference in adulthood
<p>Abstract</p> <p>Background</p> <p>Brain regions that mediate learning of a conditioned place preference (CPP) undergo significant development in pre and periadolescence. Consuming a high fat (HF) diet during this developmental period and into adulthood can lead to learning impairments in rodents. The present study tested whether HF diet intake, consumed only in pre and periadolescence, would be sufficient to cause impairments using a CPP procedure.</p> <p>Methods</p> <p>Rats were randomly assigned to consume a HF or a low fat (LF) diet during postnatal days (PD) 21-40 and were then placed back on a standard lab chow diet. A 20-day CPP procedure, using HF Cheetos<sup>® </sup>as the unconditioned stimulus (US), began either the next day (PD 41) or 40 days later (PD 81). A separate group of adult rats were given the HF diet for 20 days beginning on PD 61, and then immediately underwent the 20-day CPP procedure beginning on PD 81.</p> <p>Results</p> <p>Pre and periadolescent exposure to a LF diet or adult exposure to a HF diet did not interfere with the development of a HF food-induced CPP, as these groups exhibited robust preferences for the HF Cheetos<sup>® </sup>food-paired compartment. However, pre and periadolescent exposure to the HF diet impaired the development of a HF food-induced CPP regardless of whether it was assessed immediately or 40 days after the exposure to the HF diet, and despite showing increased consumption of the HF Cheetos<sup>® </sup>in conditioning.</p> <p>Conclusions</p> <p>Intake of a HF diet, consumed only in pre and periadolescence, has long-lasting effects on learning that persist into adulthood.</p
Normal Values Determination for High Resolution Esophageal Manometry Using Sitting Viscous Solution Swallows. Results of a Multicenter Study in Healthy Volunteers
Q1Q1Introduction: It has been suggested that a more physiologic esophageal manometry study
protocol, including non-liquid solutions and a sitting position, could improve the test
performance. For the specificity determination of putative findings it is necessary to determine
normal values Aim: To determine normal values for sitting viscous solution swallows in
healthy volunteers using high-resolution esophageal manometry.https://orcid.org/0000-0002-9219-4548Revista Nacional - Indexad
Contraction amplitude is a relevant predictor of bolus transit during sitting viscous solution swallows in healthy individuals : preliminary results of a multicenter study using high resolution impedance manometry (HRIM)
Q1Q1https://orcid.org/0000-0002-9219-4548https://orcid.org/0000-0003-1222-0636https://orcid.org/0000-0002-4523-7947Revista Internacional - Indexad
Su1876 Determination of normal esophageal pressure responses to a rapid multiple swallow challenge test. results of a multicenter study in healthy volunteers
Q1Q1https://orcid.org/0000-0002-9219-4548Revista Internacional - Indexad
A novel thymidylate synthase from the Vibrionales, Alteromonadales, Aeromonadales, and Pasteurellales (VAAP) clade with altered nucleotide and folate binding sites
Thymidylate synthase (TS, E.C. 2.1.1.45) is a crucial enzyme for de novo deoxythymidine monophosphate (dTMP) biosynthesis. The gene for this enzyme is thyA, which encodes the folate-dependent TS that converts deoxyuridine monophosphate group (dUMP) into (dTMP) using the cofactor 5,10-methylenetetrahydrofolate (mTHF) as a carbon donor. We identified the thyA gene in the genome of the Vibrio parahaemolyticus strain FIM-S1708+ that is innocuous to humans but pathogenic to crustaceans. Surprisingly, we found changes in the residues that bind the substrate dUMP and mTHF, previously postulated as invariant among all TSs known (Finer-Moore, Santi & Stroud, 2003). Interestingly, those amino acid changes were also found in a clade of microorganisms that contains Vibrionales, Alteromonadales, Aeromonadales, and Pasteurellales (VAAP) from the Gammaproteobacteria class. In this work, we studied the biochemical properties of recombinant TS from V. parahemolyticus FIM-S1708+ (VpTS) to address the natural changes in the TS amino acid sequence of the VAAP clade. Interestingly, the Km for dUMP was 27.3 ± 4.3 µM, about one-fold larger compared to other TSs. The Km for mTHF was 96.3 ± 18 µM, about three- to five-fold larger compared to other species, suggesting also loss of affinity. Thus, the catalytic efficiency was between one or two orders of magnitude smaller for both substrates. We used trimethoprim, a common antibiotic that targets both TS and DHFR for inhibition studies. The IC50 values obtained were high compared to other results in the literature. Nonetheless, this molecule could be a lead for the design antibiotics towards pathogens from the VAAP clade. Overall, the experimental results also suggest that in the VAAP clade the nucleotide salvage pathway is important and should be investigated, since the de novo dTMP synthesis appears to be compromised by a less efficient thymidylate synthase
De novo assembly and transcriptome characterization of the freshwater prawn Palaemonetes argentinus: Implications for a detoxification response
Palaemonetes argentinus, an abundant freshwater prawn species in the northern and central region of Argentina, has been used as a bioindicator of environmental pollutants as it displays a very high sensitivity to pollutants exposure. Despite their extraordinary ecological relevance, a lack of genomic information has hindered a more thorough understanding of the molecular mechanisms potentially involved in detoxification processes of this species. Thus, transcriptomic profiling studies represent a promising approach to overcome the limitations imposed by the lack of extensive genomic resources for P. argentinus, and may improve the understanding of its physiological and molecular response triggered by pollutants. This work represents the first comprehensive transcriptome-based characterization of the non-model species P. argentinus to generate functional genomic annotations and provides valuable resources for future genetic studies.
Trinity de novo assembly consisted of 24,738 transcripts with high representation of detoxification (phase I and II), anti-oxidation, osmoregulation pathways and DNA replication and bioenergetics. This crustacean transcriptome provides valuable molecular information about detoxification and biochemical processes that could be applied as biomarkers in further ecotoxicology studies.Instituto de Investigaciones Bioquímicas de La PlataInstituto de Limnología "Dr. Raúl A. Ringuelet
4to. Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad. Memoria académica
Este volumen acoge la memoria académica de la Cuarta edición del Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad, CITIS 2017, desarrollado entre el 29 de noviembre y el 1 de diciembre de 2017 y organizado por la Universidad Politécnica Salesiana (UPS) en su sede de Guayaquil.
El Congreso ofreció un espacio para la presentación, difusión e intercambio de importantes investigaciones nacionales e internacionales ante la comunidad universitaria que se dio cita en el encuentro. El uso de herramientas tecnológicas para la gestión de los trabajos de investigación como la plataforma Open Conference Systems y la web de presentación del Congreso http://citis.blog.ups.edu.ec/, hicieron de CITIS 2017 un verdadero referente entre los congresos que se desarrollaron en el país.
La preocupación de nuestra Universidad, de presentar espacios que ayuden a generar nuevos y mejores cambios en la dimensión humana y social de nuestro entorno, hace que se persiga en cada edición del evento la presentación de trabajos con calidad creciente en cuanto a su producción científica.
Quienes estuvimos al frente de la organización, dejamos plasmado en estas memorias académicas el intenso y prolífico trabajo de los días de realización del Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad al alcance de todos y todas
A Complete Review on the Application of Statistical Methods for Evaluating Internet Traffic Usage
International audienceInternet traffic classification aims to identify the kind of Internet traffic. With the rise of traffic encryption and multi-layer data encapsulation, some classic classification methods have lost their strength. In an attempt to increase classification performance, Machine Learning (ML) strategies have gained the scientific community interest and have shown themselves promising in the future of traffic classification, mainly in the recognition of encrypted traffic. However, some of these methods have a high computational resource consumption, which make them unfeasible for classification of large traffic flows or in real-time. Methods using statistical analysis have been used to classify real-time traffic or large traffic flows, where the main objective is to find statistical differences among flows or find a pattern in traffic characteristics through statistical properties that allow traffic classification. The purpose of this work is to address statistical methods to classify Internet traffic that were little or unexplored in the literature. This work is not generally focused on discussing statistical methodology. It focuses on discussing statistical tools applied to Internet traffic classification Thus, we provide an overview on statistical distances and divergences previously used or with potential to be used in the classification of Internet traffic. Then, we review previous works about Internet traffic classification using statistical methods, namely Euclidean, Bhattacharyya, and Hellinger distances, Jensen-Shannon and Kullback-Leibler (KL) divergences, Support Vector Machines (SVM), Correlation Information (Pearson Correlation), Kolmogorov-Smirnov and Chi-Square tests, and Entropy. We also discuss some open issues and future research directions on Internet traffic classification using statistical methods
Response-Inhibition Capacity and Short-Term Memory are Robust to the Effects of High Fat Diet (HFD) during Pre and Periadolescence
Several lines of evidence demonstrate that high fat diet exposure can be detrimental to cognition across the lifespan. We have previously shown that context-stimulus learning is sensitive to high fat diet effects during adolescence but not adulthood. In the present study we determined if pre and periadolescent high fat diet exposure interferes with response-inhibition capacity, rule-learning, and memory during adulthood. Rats were fed a high fat or low fat diet during pre and periadolescence and completed behavioral testing as adults to assess response-inhibition capacity and reinforcer efficacy rule-learning and short-term memory. Results indicate pre and periadolescent high fat diet may have long-term effects on reinforcer efficacy and sustained attention. However, results indicate that either the pre and periadolescence period is too short for a high fat diet to induce long-term deficits in response-inhibition, rule-learning, or memory, or that maturation in the absence of a high fat diet rescued these deficits.Several lines of evidence demonstrate that high fat diet exposure can be detrimental to cognition across the lifespan. We have previously shown that context-stimulus learning is sensitive to high fat diet effects during adolescence but not adulthood. In the present study we determined if pre and periadolescent high fat diet exposure interferes with response-inhibition capacity, rule- learning, and memory during adulthood. Rats were fed a high fat or low fat diet during pre and periadolescence and completed behavioral testing as adults to assess response-inhibition capacity and reinforcer efficacy rule-learning and short-term memory. Results indicate pre and periadolescent high fat diet may have long-term effects on reinforcer efficacy and sustained attention. However, results indicate that either the pre and periadolescence period is too short for a high fat diet to induce long-term deficits in response-inhibition, rule-learning, or memory, or that maturation in the absence of a high fat diet rescued these deficits