Effects of postnatal protein malnutrition on learning and memory procedures.

A desnutrição protéica em estágios iniciais da vida produz alterações estruturais, neuroquímicas e funcionais no sistema nervoso central, podendo causar prejuízos no desenvolvimento cognitivo e comportamental. Assim, o objetivo do presente estudo foi o de investigar os efeitos da desnutrição protéica pós-natal em tarefas que avaliam a aprendizagem e memória. Estas investigações foram feitas comparando o desempenho de ratos Wistar, submetidos à desnutrição protéica (6% de proteína) durante a lactação e pós-lactação com animais controle (16% de proteína), nas tarefas de memória operacional no Labirinto Aquático de Morris (LAM), memória de reconhecimento de objetos no campo aberto e memória operacional no Labirinto em T Aquático (LTA). No experimento I a tarefa foi localizar uma plataforma oculta que mudou de posição a cada sessão diária com quatro tentativas no LAM. A memória a longo prazo foi avaliada após seis meses utilizando-se o mesmo procedimento. No experimento II os animais foram submetidos à tarefa de reconhecimento de objetos no campo aberto, em duas tentativas com diferentes intervalos intertentativas (3 e 24h). Na 1a tentativa o animal foi habituado a um objeto A e na 2a, discriminava o objeto A de um novo objeto B. No experimento III foi testado o desempenho dos animais no LTA, sendo inicialmente forçados a alternar os braços de entrada e, após esta fase, escolher em qual braço deveria entrar para encontrar a plataforma fixada em uns dos braços. Os resultados mostraram déficits na aprendizagem e memória dos animais desnutridos no experimento I. Porém, na fase 2 a diferença entre os grupos nutricionais desapareceu. No experimento II, o índice de reconhecimento dos animais desnutridos foi significativamente maior que dos controle nos intervalos de 3 e 24h. No experimento III, houve diferença apenas do tipo de intervalo, sendo que no intervalo de 30s todos os animais demoraram mais para atingirem o critério proposto. Com estes resultados se pode concluir que a desnutrição protéica pós-natal causou prejuízos na memória operacional no LAM; porém, este déficit diminuiu seis meses depois, sugerindo que a recuperação nutricional foi eficiente para reverter as alterações causadas pela desnutrição. A tarefa de memória operacional no LTA não foi afetada por este modelo de desnutrição, independente do intervalo. Entretanto, a tarefa de memória de reconhecimento foi prejudicada pela desnutrição pós-natal, independente do intervalo, e a atividade exploratória somente no intervalo de 24h.Early protein malnutrition induces structural, neurochemical and functional changes in the Central Nervous System leading to alterations in cognitive and behavioral development of rats such as spatial learning and memory. The aim of this work was to investigate the effects of postnatal protein malnutrition on learning and memory tasks. This evaluation was done by comparing the performance of previously malnourished male Wistar rats (6% protein) from birth to 49 days of age with well-nourished control animals (16% protein) in three experiments: working memory tasks in the Morris water maze (Experiment I) at 70 days of age (phase 1) and six months later (phase 2), recognition memory of objects in the open field (Experiment II) with two types of intervals (3 and 24) between the trials, and working memory in the water T-maze (Experiment III) with two types of intervals between trials (10 and 30 s). The results showed that the escape latency in malnourished animals in experiment I was significantly higher than escape latency in controls. On phase 2, this difference disappeared. In Experiment II, recognition indexes of malnourished groups were significantly higher in both 3-h and 24-h intervals. In Experiment III, there was a difference only in the type of interval, as the animals took longer to achieve the criteria in the 30-s interval. These results suggest that protein malnutrition caused impairments on the working memory in the Morris water maze, but these deficits disappeared after nutritional recovery. Recognition memory was impaired by postnatal malnutrition independently of the type of interval. Working memory in the water T-maze was not affected by postnatal protein malnutrition

Cross-protective effect of a combined L5 plus L3 Leishmania major

Abstract Background Two Leishmania major ribosomal proteins L3 (LmL3) and L5 (LmL5) have been described as protective molecules against cutaneous leishmaniasis due to infection with L. major and Leishmania braziliensis in BALB/c mice when immunized with a Th1 adjuvant (non-methylated CpG-oligodeoxynucleotides; CpG-ODN). In the present study we analyzed the cross-protective efficacy of an LmL3-LmL5-CpG ODN combined vaccine against infection with Leishmania amazonensis and Leishmania chagasi (syn. Leishmania infantum) the etiologic agents of different clinical forms of human leishmaniasis in South America. Methods The combined vaccine was administered subcutaneously to BALB/c mice. After immunization the cellular and humoral responses elicited were analyzed. Mice were independently challenged with L. amazonensis and L. chagasi. The size of the cutaneous lesions caused by the infection with the first species, the parasite loads and the immune response in both infection models were analyzed nine weeks after challenge. Results Mice vaccinated with the combined vaccine showed a Th1-like response against LmL3 and LmL5. Vaccinated mice were able to delay lesion development due to L. amazonensis infection and to control parasite loads in the site of infection. A reduction of the parasite burden in the lymph nodes draining the site of infection and in the liver and spleen was observed in the vaccinated mice after a subcutaneous infection with L. chagasi. In both models of infection, protection was correlated to parasite antigen-specific production of IFN-γ and down-regulation of parasite-mediated IL-4 and IL-10 responses. Conclusions The data presented here demonstrate the potential use of L. major L3 and L5 recombinant ribosomal proteins for the development of vaccines against various Leishmania species.The study was supported in Spain by grants from Laboratorios LETI S.L.u-Fundación Severo Ochoa, from Ministerio de Ciencia e Innovación FIS/PI080101 and FIS PI11/00095 and from the Instituto de Salud Carlos III within the Network of Tropical Diseases Research (VI P I + D + I 2008–2011, ISCIII -Subdirección General de Redes y Centros de Investigación Cooperativa (RD12/0018/0009)).Peer Reviewe

NEOTROPICAL CARNIVORES: a data set on carnivore distribution in the Neotropics

Mammalian carnivores are considered a key group in maintaining ecological health and can indicate potential ecological integrity in landscapes where they occur. Carnivores also hold high conservation value and their habitat requirements can guide management and conservation plans. The order Carnivora has 84 species from 8 families in the Neotropical region: Canidae; Felidae; Mephitidae; Mustelidae; Otariidae; Phocidae; Procyonidae; and Ursidae. Herein, we include published and unpublished data on native terrestrial Neotropical carnivores (Canidae; Felidae; Mephitidae; Mustelidae; Procyonidae; and Ursidae). NEOTROPICAL CARNIVORES is a publicly available data set that includes 99,605 data entries from 35,511 unique georeferenced coordinates. Detection/non-detection and quantitative data were obtained from 1818 to 2018 by researchers, governmental agencies, non-governmental organizations, and private consultants. Data were collected using several methods including camera trapping, museum collections, roadkill, line transect, and opportunistic records. Literature (peer-reviewed and grey literature) from Portuguese, Spanish and English were incorporated in this compilation. Most of the data set consists of detection data entries (n = 79,343; 79.7%) but also includes non-detection data (n = 20,262; 20.3%). Of those, 43.3% also include count data (n = 43,151). The information available in NEOTROPICAL CARNIVORES will contribute to macroecological, ecological, and conservation questions in multiple spatio-temporal perspectives. As carnivores play key roles in trophic interactions, a better understanding of their distribution and habitat requirements are essential to establish conservation management plans and safeguard the future ecological health of Neotropical ecosystems. Our data paper, combined with other large-scale data sets, has great potential to clarify species distribution and related ecological processes within the Neotropics. There are no copyright restrictions and no restriction for using data from this data paper, as long as the data paper is cited as the source of the information used. We also request that users inform us of how they intend to use the data