523 research outputs found
Refinement of neuronal synchronization with gamma oscillations in the medial prefrontal cortex after adolescence
The marked anatomical and functional changes taking place in the medial prefrontal cortex (PFC) during adolescence set grounds for the high incidence of neuropsychiatric disorders with adolescent onset. Although circuit refinement through synapse pruning may constitute the anatomical basis for the cognitive differences reported between adolescents and adults, a physiological correlate of circuit refinement at the level of neuronal ensembles has not been demonstrated. We have recorded neuronal activity together with local field potentials in the medial PFC of juvenile and adult mice under anesthesia, which allowed studying local functional connectivity without behavioral or sensorial interference. Entrainment of pyramidal neurons and interneurons to gamma oscillations, but not to theta or beta oscillations, was reduced after adolescence. Interneurons were synchronized to gamma oscillations across a wider area of the PFC than pyramidal neurons, and the span of interneuron synchronization was shorter in adults than juvenile mice. Thus, transition from childhood to adulthood is characterized by reduction of the strength and span of neuronal synchronization specific to gamma oscillations in the mPFC. The more restricted and weak ongoing synchronization in adults may allow a more dynamic rearrangement of neuronal ensembles during behavior and promote parallel processing of information.Fil: de Almeida, Julián. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Ciencias Fisiológicas. Laboratorio de Fisiología de Circuitos Neuronales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Jourdan, Iván. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Ciencias Fisiológicas. Laboratorio de Fisiología de Circuitos Neuronales; Argentina. Universidad de Buenos Aires. Facultad de Ingeniería; ArgentinaFil: Murer, Mario Gustavo. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Ciencias Fisiológicas. Laboratorio de Fisiología de Circuitos Neuronales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Belforte, Juan Emilio. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Ciencias Fisiológicas; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Ciencias Fisiológicas. Laboratorio de Fisiología de Circuitos Neuronales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
Brasil e Colômbia: desenvolvimento, saúde e práticas espaciais
Os governos latino-americanos da Colômbia e do Brasil oferecem serviços de saúde para as populações rurais que, segundo os próprios movimentos camponeses, na maioria das vezes, não contemplam suas necessidades específicas. Na busca de melhor entender essa realidade, foi realizada uma análise das experiências relacionadas à saúde e às práticas espaciais das comunidades camponesas no Brasil e na Colômbia, refletindo sobre suas condições, seus conhecimentos, as influencias que estes conhecimentos têm, procurando identificar a realidade dos atendimentos em saúde para estas comunidades e escutando a opinião da população rural sobre essa temática. Entendendo que a promoção à saúde está para além de somente morar no campo, ressaltamos ser necessário condições mínimas para garantir a qualidade de vida, através do cuidado com a natureza, com a água e com a alimentação. No Brasil, a forte influência da cidade no campo faz com que as comunidades estejam dependentes dos produtos e processos que a urbanidade oferece. Na Colômbia, o choque com as realidades urbanas tem sido ainda mais forte, uma vez que os indígenas têm precisado viver numa realidade que desconheciam nas suas comunidades ancestrais e tem precisado conviver com pessoas que não os escutam nem os entendem nem estão abertos a entendê-los. Esta constante dicotomia entre campo e cidade, nas duas realidades visitadas, faz com que as práticas espaciais passem por modificações constantemente. Da visita no resguardo indígena se aprendeu que a saúde tem se enfraquecido porque a ‘Madre Tierra’ não está sendo respeitada
Pr 0.5 Ca 0.5 MnO 3 thin films deposited on LiNbO 3 substrates
Thin films of Pr 0.5 Ca 0.5 MnO 3 have been deposited on z-cut LiNbO 3 by pulsed laser ablation. The X-ray diffraction measurements showed that the films have grown highly oriented on LiNbO 3 , with a pseudocubic (111) preferred growth direction. The thicknesses of the films, measured by low angle X-ray reflectivity, are between 13 and 140 nm. Their electrical resistivity present a semiconducting-like behaviour with an anomaly around 240 K, that corresponds to the charge ordering transition. The temperature of the transition (T_CO) was estimated from ln(r) vs. (1/T) plots. The charge ordering temperature was found to be dependent on the strain induced by the lattice mismatch on the films.Fundação para a Ciência e a Tecnologia (FCT
The mineralocorticoid receptor forms higher order oligomers upon DNA binding
peer reviewe
Therapeutic DNA Vaccine Encoding Peptide P10 against Experimental Paracoccidioidomycosis
Paracoccidioidomycosis (PCM), caused by Paracoccidioides brasiliensis, is the most prevalent invasive fungal disease in South America. Systemic mycoses are the 10th most common cause of death among infectious diseases in Brazil and PCM is responsible for more than 50% of deaths due to fungal infections. PCM is typically treated with sulfonamides, amphotericin B or azoles, although complete eradication of the fungus may not occur and relapsing disease is frequently reported. A 15-mer peptide from the major diagnostic antigen gp43, named P10, can induce a strong T-CD4+ helper-1 immune response in mice. The TEPITOPE algorithm and experimental data have confirmed that most HLA-DR molecules can present P10, which suggests that P10 is a candidate antigen for a PCM vaccine. In the current work, the therapeutic efficacy of plasmid immunization with P10 and/or IL-12 inserts was tested in murine models of PCM. When given prior to or after infection with P. brasiliensis virulent Pb 18 isolate, plasmid-vaccination with P10 and/or IL-12 inserts successfully reduced the fungal burden in lungs of infected mice. In fact, intramuscular administration of a combination of plasmids expressing P10 and IL-12 given weekly for one month, followed by single injections every month for 3 months restored normal lung architecture and eradicated the fungus in mice that were infected one month prior to treatment. The data indicate that immunization with these plasmids is a powerful procedure for prevention and treatment of experimental PCM, with the perspective of being also effective in human patients
The First Bromeligenous Species of Dendropsophus (Anura: Hylidae) from Brazil\u27s Atlantic Forest
We describe a new treefrog species of Dendropsophus collected on rocky outcrops in the Brazilian Atlantic Forest. Ecologically, the new species can be distinguished from all known congeners by having a larval phase associated with rainwater accumulated in bromeliad phytotelms instead of temporary or lentic water bodies. Phylogenetic analysis based on molecular data confirms that the new species is a member of Dendropsophus; our analysis does not assign it to any recognized species group in the genus. Morphologically, based on comparison with the 96 known congeners, the new species is diagnosed by its small size, framed dorsal color pattern, and short webbing between toes IV-V. The advertisement call is composed of a moderate-pitched two-note call (~5 kHz). The territorial call contains more notes and pulses than the advertisement call. Field observations suggest that this new bromeligenous species uses a variety of bromeliad species to breed in, and may be both territorial and exhibit male parental care
Constitutional and somatic methylation status of DMRH19 and KvDMR in Wilms tumor patients
Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2
The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality
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