125 research outputs found

    Thalamic interaction between the input and the output systems of the basal ganglia

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    The striatal return through the thalamus is largely neglected in current studies dealing with basal ganglia function, and its role within this circuitry remains obscure. In this contribution the thalamus is regarded as an important place of interaction between the input and the output organization of the basal ganglia. In support of this idea, a brief overview is provided of some of the most recent findings concerning the thalamus in relation to the basal ganglia circuitry. In particular, we have focused on the thalamostriatal projections themselves, on the output of the basal ganglia to the thalamus and also on the overlapping territories between the thalamic projection of the output nuclei and the thalamostriatal neurons. These data support the existence of several thalamic feedback circuits within the basal ganglia neural system. Finally, some considerations are provided upon the functional significance of these thalamic feedback circuits in the overall organization of the basal ganglia

    A role for an Hsp70 nucleotide exchange factor in the regulation of synaptic vesicle endocytosis

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    © The Author(s), 2013. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Journal of Neuroscience 33 (2013): 8009-8021, doi:10.1523/JNEUROSCI.4505-12.2013.Neurotransmission requires a continuously available pool of synaptic vesicles (SVs) that can fuse with the plasma membrane and release their neurotransmitter contents upon stimulation. After fusion, SV membranes and membrane proteins are retrieved from the presynaptic plasma membrane by clathrin-mediated endocytosis. After the internalization of a clathrin-coated vesicle, the vesicle must uncoat to replenish the pool of SVs. Clathrin-coated vesicle uncoating requires ATP and is mediated by the ubiquitous molecular chaperone Hsc70. In vitro, depolymerized clathrin forms a stable complex with Hsc70*ADP. This complex can be dissociated by nucleotide exchange factors (NEFs) that release ADP from Hsc70, allowing ATP to bind and induce disruption of the clathrin:Hsc70 association. Whether NEFs generally play similar roles in vesicle trafficking in vivo and whether they play such roles in SV endocytosis in particular is unknown. To address this question, we used information from recent structural and mechanistic studies of Hsp70:NEF and Hsp70:co-chaperone interactions to design a NEF inhibitor. Using acute perturbations at giant reticulospinal synapses of the sea lamprey (Petromyzon marinus), we found that this NEF inhibitor inhibited SV endocytosis. When this inhibitor was mutated so that it could no longer bind and inhibit Hsp110 (a NEF that we find to be highly abundant in brain cytosol), its ability to inhibit SV endocytosis was eliminated. These observations indicate that the action of a NEF, most likely Hsp110, is normally required during SV trafficking to release clathrin from Hsc70 and make it available for additional rounds of endocytosis.This work was supported by the National Institutes of Health (Grant #NS029051 to E.M.L. and Grant #NS078165 to J.R.M.).2013-11-0

    REVASCULARIZAÇÃO CONVENCIONAL ULTRA-DISTAL NA ISQUEMIA CRÍTICA

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    Introdução: A cirurgia convencional de revascularização ultra-distal continua a ser pouco utilizada pela maioria dos cirurgiões vasculares. No entanto, os escassos estudos publicados mostram resultados muito favoráveis em termos de sobrevida e salvação de membro. Objetivos: Avaliar os resultados da cirurgia convencional de revascularização ultra-distal em doentes com isquemia crítica grau IV (estadios 5 e 6 da classificação de Rutherford); analisar os detalhes técnicos e de decisão cirúrgica que influenciam os resultados obtidos. Material e métodos: Estudo retrospetivo, envolvendo todos os doentes admitidos nesta instituição com isquemia crítica nos estadios 5 e 6 da classificação de Rutherford, submetidos a cirurgia convencional de revascularização ultra-distal. Foi considerado critério de inclusão a cirurgia de bypass às artérias plantares comum, interna ou externa e à artéria pediosa. Foi avaliada a mortalidade, taxa de preservação de membro, sobrevida livre de amputação major e permeabilidade da revascularização, por intermédio de curvas de Kaplan-Meier. Resultados: Entre Abril de 2012 e Março de 2016, 41 doentes (34 homens e 7 mulheres) com uma média de idades de 69.1 anos, foram submetidos a 50 procedimentos de revascularização ultra-distal, 35 dos quais à artéria pediosa, 10 a artérias plantares e 5 a procedimentos de resgate de failing graft. Em 84% das revascularizações (n=42) utilizou-se substituto venoso autólogo, sendo os restantes bypass compostos de PTFE e veia (n=8). O follow-up médio foi de 20.8 meses (2-47 meses). Não registámos qualquer mortalidade aos 30 dias e durante o follow-up a mortalidade global foi 7.3% (n=3). Ocorreram 9 oclusões das revascularizações (2 precoces e 7 tardias) e 5 amputações major. A permeabilidade primária foi de 78% e a permeabilidade primária assistida de 82%. A taxa de preservação de membro foi de 88.9% e, no final do follow-up, a sobrevida livre de amputação foi de 66%. Conclusões: Os resultados demonstram que, em centros especializados e com elevado volume, esta técnica é muito eficaz na salvação de membros em isquemia crítica nos estadios 5 e 6 da classificação de Rutherford. Estes procedimentos devem ser tomados em consideração na ausência de outros vasos pontáveis ou como resgate, em membros já submetidos a procedimentos de revascularização prévios

    Antibacterial evaluation of Styrax pohlii and isolated compounds

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    The antibacterial activity of the compounds egonol (1) and homoegonol (2), of the crude ethanolic extract of Styrax pohlii (Styracaceae) aerial parts (EE), and of its n-hexane (HF), EtOAc (EF), n-BuOH (BF), and hydromethanolic (HMF) fractions was evaluated against the following microorganisms: Streptococcus pneumoniae (ATCC 6305), S. pyogenes (ATCC 19615), Haemophilus influenzae (ATCC 10211), Pseudomonas aeruginosa (ATCC 27853), and Klebsiella pneumoniae (ATCC 10031). The broth microdilution method was used for determination of the minimum inhibitory concentration (MIC) during preliminary evaluation of antibacterial activity. The EE yielded MIC values of 400 µg/mL for S. pneumoniae and P. aeruginosa and 300 µg/mL for H. influenzae. The HF and EF fractions exhibited enhanced antibacterial activity, with MIC values of 200 µg/mL against S. pneumoniae, but only EF displayed activity against H. influenzae (MIC 200 µg/mL). The best MIC value with compounds 1 and 2 (400 µg/mL) was obtained for (1) against S. pneumoniae and P. aeruginosa. Therefore, 1 exhibited weak antibacterial activity against these standard strains.As atividades antimicrobianas das substâncias egonol (1) e homoegonol (2), do extrato etanólico das partes aéreas de Styrax pohlii (Styracaceae) (EE), bem como das frações n-hexano (HF), AcOEt (EF), n-BuOH (BF) e hidrometanólica (HMF) foram avaliadas frente aos seguintes microorganismos: Streptococcus pneumoniae (ATCC 6305), S. pyogenes (ATCC 19615), Haemophilus influenzae (ATCC 10211), Pseudomonas aeruginosa (ATCC 27853) e Klebsiella pneumoniae (ATCC 10031). O método de microdiluição em caldo foi utilizado para a determinação da concentração inibitória mínima (CIM) na avaliação preliminar da atividade antimicrobiana. EE mostrou valores de CIM de 400 µg/mL para S. pneumoniae e P. aeruginosa, e 300 µg/mL para H. influenzae. As frações HF e EF apresentaram melhora na atividade antimicrobiana, com valores de CIM de 200 µg/mL frente S. pneumoniae, mas apenas EF apresentou ação contra H. influenzae (200 µg/mL). Em relação às substâncias 1 e 2, o melhor valor de CIM (400 µg/mL) foi obtido por 1 frente a S. pneumoniae e P. aeruginosa, que exibiu fraca atividade antimicrobiana contra estas cepas padrões

    Structure of the Hsp110:Hsc70 nucleotide exchange machine.

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    Hsp70s mediate protein folding, translocation, and macromolecular complex remodeling reactions. Their activities are regulated by proteins that exchange ADP for ATP from the nucleotide-binding domain (NBD) of the Hsp70. These nucleotide exchange factors (NEFs) include the Hsp110s, which are themselves members of the Hsp70 family. We report the structure of an Hsp110:Hsc70 nucleotide exchange complex. The complex is characterized by extensive protein:protein interactions and symmetric bridging interactions between the nucleotides bound in each partner protein\u27s NBD. An electropositive pore allows nucleotides to enter and exit the complex. The role of nucleotides in complex formation and dissociation, and the effects of the protein:protein interactions on nucleotide exchange, can be understood in terms of the coupled effects of the nucleotides and protein:protein interactions on the open-closed isomerization of the NBDs. The symmetrical interactions in the complex may model other Hsp70 family heterodimers in which two Hsp70s reciprocally act as NEFs

    Virosis en maíz transmitidas por ácaros. campañas 2020/21 y 2021/22

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    PosterWheat streak mosaic virus (WSMV) y High plains wheat mosaic virus HPWMoV ), transmitidos por el ácaro Aceria tosichella (Fig. 1), se identificaron por primera vez en cultivos de maíz del país en 2010 y 2014, respectivamente (Fig. 2). Fueron informados en trigo en 2006, al inicio de epifitia de WSMV en el sur de Buenos Aires. Son frecuentes las infecciones mixtas entre ellos y con otros virus, siendo en maíz mucho más relevantes los síntomas de HPWMoV.Instituto de Patología VegetalFil: Colella, E. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; ArgentinaFil: Palacio, C. Universidad Nacional del Noroeste de la Provincia de Buenos Aires. Servicios de Investigación y Estudios Fitopatológicos; ArgentinaFil: Pagnan, Luis Federico. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Marcos Juárez. Agencia De Extensión Rural Justiniano Posse; ArgentinaFil: Ruiz Posse, Agustina María. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Fitopatología y Modelización Agrícola (UFyMA); ArgentinaFil: Ruiz Posse, Agustina María. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; ArgentinaFil: Ferrer Lanfranchi, Mariana. Innovaciones tecnológicas Agropecuarias S.A. (INTEA); ArgentinaFil: Ferrer Lanfranchi, Mariana. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; ArgentinaFil: Torrico Ramallo, Ada Karina. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; ArgentinaFil: Torrico Ramallo, Ada Karina. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Fitopatología y Modelización Agrícola (UFyMA); ArgentinaFil: Gimenez, Maria De La Paz. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patología Vegetal; ArgentinaFil: Gimenez, Maria De La Paz. Consejo Nacional de Investigaciones Científicas y Técnicas. Unidad de Fitopatología y Modelización Agrícola (UFyMA); Argentin

    Recruitment Disruption and the Role of Unaffected Populations for Potential Recovery After the Pinna nobilis Mass Mortality Event

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    A devastating mass mortality event (MME) very likely caused by the protozoan Haplosporidium pinnae first detected in 2016 in the Western Mediterranean Sea, is pushing the endemic bivalve Pinna nobilis to near extinction. Populations recovery, if possible, will rely on larval dispersal from unaffected sites and potential recolonization through recruitment of resistant juveniles. To assess the impact of the MME on the species’ larval recruitment, an unprecedented network of larval collector stations was implemented over several thousands of kilometers along the Western Mediterranean coasts during the 3 years after the onset of the MME. The findings of this network showed a generalized disruption in recruitment with dramatic consequences for the recovery of the species. However, there were exceptions to this pattern and recruits were recorded in a few sites where the resident population had been decimated. This hints to the importance of unaffected populations as larval exporting sources and the role of oceanographic currents in larval transport in the area, representing a beacon of hope in the current extremely worrying scenario for this emblematic species.En prens

    GEICAM Guidelines for the Management of Patients with Breast Cancer During the COVID-19 Pandemic in Spain

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    Breast cancer (BC) is the most common cancer in women in Spain. During the COVID-19 pandemic caused by the SARSCoV-2 virus, patients with BC still require timely treatment and follow-up; however, hospitals are overwhelmed with infected patients and, if exposed, patients with BC are at higher risk for infection and serious complications if infected. Thus, health care providers need to evaluate each BC treatment and in-hospital visit to minimize pandemic-associated risks while maintaining adequate treatment efficacy. Here we present a set of guidelines regarding available options for BC patient management and treatment by BC subtype in the context of the COVID-19 pandemic. Owing to the lack of evidence about COVID-19 infection, these recommendations are mainly based on expert opinion, medical organizations’ and societies’ recommendations, and some published evidence. We consider this a useful tool to facilitate medical decision making in this health crisis situation we are facing

    Polymorphism of the FABP2 gene: a population frequency analysis and an association study with cardiovascular risk markers in Argentina

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    <p>Abstract</p> <p>Background</p> <p>The FABP2 gene encodes for the intestinal FABP (IFABP) protein, which is expressed only in intestinal enterocytes. A polymorphism at codon 54 in exon 2 of the FABP2 gene exchanges an Alanine (Ala), in the small helical region of the protein, for Threonine (Thr). Given the potential physiological role of the Ala54Thr FABP2 polymorphism, we assess in this study the local population frequency and analyze possible associations with five selected markers, i.e. glycemia, total cholesterol, body mass index (BMI), hypertension, and high Cardiovascular Risk Index (CVR index).</p> <p>Methods</p> <p>We studied 86 men and 116 women. DNA was extracted from a blood drop for genotype analysis. Allele frequencies were calculated by direct counting. Hardy Weinberg Equilibrium was evaluated using a Chi-square goodness of fit test.</p> <p>For the polymorphism association analysis, five markers were selected, i.e. blood pressure, Framingham Risk Index, total cholesterol, BMI, and glycemia.</p> <p>For each marker, the Odds Ratio (OR) was calculated by an online statistic tool.</p> <p>Results</p> <p>Our results reveal a similar population polymorphism frequency as in previous European studies, with <b>q = 0.277 </b>(95% confidence limits 0.234–0.323). No significant association was found with any of the tested markers in the context of our Argentine nutritional and cultural habits. We did, however, observe a tendency for increased Cholesterol and high BMI in Thr54 carriers.</p> <p>Conclusion</p> <p>This is the first study to look at the population frequency of the Thr54 allele in Argentina. The obtained result does not differ from previously reported frequencies in European populations. Moreover, we found no association between the Thr54 allele and any of the five selected markers. The observed tendency to increased total cholesterol and elevated BMI in Thr54 carriers, even though not significant for p < 0.1 could be worth of further investigation to establish whether the Thr54 variant should be taken into consideration in cardiovascular prevention strategies.</p

    Enfermedades del maíz de siembra tardía causadas por hongos

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    Fil: De Rossi, Roberto Luis. Universidad Católica de Córdoba. Facultad de Ciencias Agropecuarias; ArgentinaFil: Giménez Pecci, María de la Paz. Universidad Católica de Córdoba. Facultad de Ciencias Agropecuarias; ArgentinaFil: Guerra, Fernando Andrés. Universidad Católica de Córdoba. Facultad de Ciencias Agropecuarias; ArgentinaFil: Plazas, María Cristina. Universidad Católica de Córdoba. Facultad de Ciencias Agropecuarias; ArgentinaFil: Brücher, Elsa. Universidad Católica de Córdoba. Facultad de Ciencias Agropecuarias; ArgentinaFil: Guerra, Gustavo Darío. Universidad Católica de Córdoba. Facultad de Ciencias Agropecuarias; ArgentinaFil: Barontini, Javier Miguel. Universidad Católica de Córdoba. Facultad de Ciencias Agropecuarias; Argentin
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