3, 4-metilenedioximetafetamina reverte a ansiedade induzida por estresse crônico moderado

Here we report the effects of subchronic 3, 4-Methylenedioximethamphetamine (MDMA) on the elevated plus-maze, a widely used animal model of anxiety. Rats exposed to a mild chronic stress (MCS) protocol received intracerebroventricular microinjections of the selective serotonin reuptake inhibitor (SSRI) – fluoxetine (2.0ug/ul) or 3, 4-Methylenedioximethamphetamine (MDMA, 2.0ug/ul) for seven days. On the eighth day rats were tested in the elevated plus-maze. Our results showed that sub-chronic MDMA interacted with MCS leading to a decrease in anxiety-related behaviors including: percentage of open arms entries (F[2,26]=4.00; P=0.031), time spent in the open arms (F[2,26]=3.656; P=0.040) and time spent in the open arms extremities (F[2,26]=5.842; P=0.008). These results suggest a potential effect of MDMA in the reversion of the emotional significance of aversive stimuli.Reportamos aquí los efectos de la administración subcrónica de 3, 4-metilendioximetanfetamina (MDMA) sobre el laberinto en cruz elevado, un modelo animal de ansiedad ampliamente utilizado. Las ratas fueron expuestas a un protocolo de estrés crónico moderado (MCS) y recibieron microinyecciones intra-cerebroventriculares del inhibidor selectivo de la recaptación de serotonina (SSRI)-fluoxetina (2,0 ug/ul) o de MDMA (0,2 ug/ul) durante siete días. En el octavo día las ratas fueron probadas en el laberinto en cruz elevado. Los resultados mostraron que la administración subcrónica de MDMA interactuó con el MCS, llevando a un decremento de los comportamientos relacionados con la ansiedad, incluyendo: porcentaje de entradas a los brazos abiertos (F [2, 26] = 4.00; p = 0.031), el tiempo empleado explorando los brazos abiertos (F [2, 26] = 3.656; p = 0.040) y el tiempo empleado explorando las extremidades de los brazos abiertos (F [2, 26] = 5.842; p = 0.008). Estos resultados sugieren un potencial efecto de MDMA en la reversión del significado emocional de los estímulos aversivos.Os efeitos da administração sub-crônica de 3, 4-metilenedioximetanfetamina (MDMA) no labirinto em cruz elevado, um modelo amplamente utilizado no estudo da ansiedade, foram testados. Ratos submetidos a um protocolo de estresse crônico moderado (MCS) receberam micro injeções intra cérebro ventriculares do inibidor seletivo da recaptação de serotonina (SSRI)-fluoxetina (2.0ug/ul) ou MDMA (2.0 ug/ul) durante sete dias. No oitavo dia, os ratos foram testados no labirinto em cruz elevado. Os resultados sugerem que a administração sub-crônica de MDMA interagiu com o MCS levando à diminuição dos comportamentos relacionados com ansiedade, incluindo: porcentagem de entradas aos braços abertos (F [2, 26] = 4.00; p = 0.031), o tempo gasto explorando os braços abertos (F [2, 26] = 3.656; p = 0.040) e o tempo gasto explorando as extremidades dos braços abertos (F [2, 26] = 5.842; p = 0.008

Caminos de la neurociencia en América Latina

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Modelling control strategies against Classical Swine Fever: influence of traders and markets using static and temporal networks in Ecuador

Classical swine fever (CSF) in Ecuador is prevalent since 1940, pig farming represents an important economic and cultural sector. Recently, the National Veterinary Service (NVS) has implemented individual identification of pigs, movement control and mandatory vaccination against CSF, looking for a future eradication. Our aim was to characterise the pig premises according to risk criteria, analyse the effect of random and targeted strategies to control CSF and consider the temporal development of the network. We used social network analysis (SNA), SIRS (susceptible, infected, recovered, susceptible) network modelling and temporal network analysis. The data set contained 751,003 shipments and 6 million pigs from 2017 to 2019. 165,593 premises were involved: 144,118 farms, 138 industrials, 21,337 traders, and 51 markets. On annual average, 124,976 premises (75%) received or sent one movement with 1.5 pigs, in contrast, 166 (0.01%) with 1,372 movements and 11,607 pigs. Simulations resulted in CSF mean prevalence of 29.93%; Targeted selection strategy reduced the prevalence to 3.3%, while 24% with random selection. Selection of high-risk premises in every province was the best strategy using available surveillance infrastructure. Notably, selecting 10 traders/markets reduced the CSF prevalence to 4%, evidencing their prime influence over the network. Temporal analysis showed an overestimation of 38% (causal fidelity) in the number of transmission paths; The steps to cross the network were 4.3 (average path length), but take approximately 233 days. In conclusion, surveillance strategies applied by the NVS could be more efficient to find cases, reduce the spread of diseases and enable the implementation of risk-based surveillance. To focus the efforts on target selection of high-risk premises, special attention should be given to markets/traders which proved similar disease spread potential

Concentrações plasmáticas de corticosterone em ratos Carioca Alto- e Carioca Bajo-Congelamento condicionado após uma tarefa de medo condicionado

Our group in the Psychology Department at Pontifícia Universidade Católica do Rio de Janeiro (PUC-Rio) developed a rat genetic model of extreme freezing in response to contextual cues in an experimental chamber previously associated with footshock. One of the lines, Carioca High Freezing (CHF), exhibits an enhanced conditioned freezing response, whereas the other line, Carioca Low Freezing (CLF), shows the opposite response. The present study investigated corticosterone concentration between these two lines of animals and a random (RND) line of rats both under basal conditions and test condition after an emotional challenge using a contextual fear conditioning protocol. Comparisons between basal and test plasma corticosterone concentrations suggested differential basal and fear-induced differences between the two lines. The differences between basal conditions is an important and relevant aspect to be considered in behavioral experiments using or assessing stress and could help to understand variability in naïve populations.Casi toda la investigación farmacológica en estrés y desórdenes de ansiedad es realizada generalmente en poblaciones de animales que se supone son comparables. En el laboratorio de Neurociencia Comportamental de la Pontificia Universidad Católica de Río de Janeiro (Brasil), dos nuevas líneas de ratas Wistar fueron aisladas por la selección fenotípica de la respuesta emocional en el protocolo de condicionamiento de la respuesta de miedo. Una de las líneas, denominada Carioca High Freezing (CHF) muestra una respuesta aumentada de congelamiento en el test, mientras que la otra –Carioca Low Freezing (CLF)– muestra la respuesta opuesta. Aquí presentamos datos orientados a evaluar las condiciones basales y la vulnerabilidad al estrés entre las dos líneas. Los niveles de corticosterona fueron comparados entre las dos líneas tanto en condiciones basales como después de un desafío emocional utilizando el protocolo de miedo condicionado. La comparación entre las concentraciones plasmáticas de corticosterona basal y luego del retest sugiere diferencias basales y diferencias inducidas por el miedo entre las dos líneas. Las diferencias en las condiciones basales es un aspecto importante y relevante que debe ser considerado en experimentos comportamentales que usen o evalúen el estrés y podría ayudar a comprender la variabilidad encontrada en las poblaciones.Nosso grupo no Departamento de Psicologia da Universidade Católica do Rio de Janeiro desenvolveu um modelo genético com ratos que apresentam respostas extremas de congelamento a estímulos contextuais de uma caixa experimental previamente associados a choques elétricos. Uma das linhagens, Carioca High Freezing (CHF) apresenta uma resposta aumentada de congelamento condicionado. A outra linhagem, Carioca Low Freezing (CLF) apresenta a resposta de congelamento condicionada em direção oposta. O presente trabalho comparou os níveis de corticosterona entre as duas linhagens assim como uma terceira linhagem com cruzamento aleatório (RND) tanto em condições basais assim como em um teste onde os animais foram expostos á situação de condicionamento contextual de medo. A comparação entre as concentrações plasmáticas de corticosterona basal e depois do teste sugere diferenças basais assim como diferenças induzidas pelo medo condicionado entre as duas linhagens. As diferenças nas condições basais é um aspecto importante e relevante que deve ser levado em consideração em experimentos que avaliem o estresse e pode ajudar na compreensão da variabilidade nas populações

Urinary exosome miR-146a is a potential marker of albuminuria in essential hypertension

BACKGROUND: There is increasing interest in using extracellular vesicle-derived microRNAs (miRNAs) as biomarkers in renal dysfunction and injury. Preliminary evidence indicates that miRNAs regulate the progression of glomerular disease. Indeed, exosomes from the renal system have provided novel evidence in the clinical setting of albuminuria. Thus, the aim of this study was to quantify the urinary miRNAs present in exosome and microvesicles (MVs), and to assess their association with the presence of increased urinary albumin excretion in essential hypertension. METHODS: Exosomes were collected from urine specimens from a cohort of hypertensive patients with (n = 24) or without albuminuria (n = 28), and from 20 healthy volunteers as a control group. Urinary exosomes were phenotyped by Western blot, tunable resistive pulse sensing, and electronic microscopy. Expression of miR-146a and miR-335* was analysed by qRT-PCR and any associations between albuminuria and exosomal miRNAs were analysed. RESULTS: Urinary miRNAs are highly enriched in exosome subpopulations compared to MVs, both in patients with or without increased albuminuria (p < 0.001), but not in the control group. High albuminuria was associated with 2.5-fold less miR-146a in exosomes (p = 0.017), whereas miR-146a levels in MV did not change. In addition, exosome miR-146a levels were inversely associated with albuminuria (r = 0.65, p < 0.0001), and discriminated the presence of urinary albumin excretion presence [area under the curve = 0.80, 95% confidence interval: 0.66-0.95; p = 0.0013]. CONCLUSIONS: Our results indicate that miRNAs were enriched in the urinary exosome subpopulation in hypertensive patients and that low miR-146a expression in exosomes was associated with the presence of albuminuria. Thus, urinary exosome miR-146a may be a potentially useful tool for studying early renal injury in hypertension

Local spatial structure of forest biomass and its consequences for remote sensing of carbon stocks

Advances in forest carbon mapping have the potential to greatly reduce uncertainties in the global carbon budget and to facilitate effective emissions mitigation strategies such as REDD+. Though broad scale mapping is based primarily on remote sensing data, the accuracy of resulting forest carbon stock estimates depends critically on the quality of field measurements and calibration procedures. The mismatch in spatial scales between field inventory plots and larger pixels of current and planned remote sensing products for forest biomass mapping is of particular concern, as it has the potential to introduce errors, especially if forest biomass shows strong local spatial variation. Here, we used 30 large (8–50 ha) globally distributed permanent forest plots to quantify the spatial variability in aboveground biomass (AGB) at spatial grains ranging from 5 to 250m (0.025–6.25 ha), and we evaluate the implications of this variability for calibrating remote sensing products using simulated remote sensing footprints. We found that the spatial sampling error in AGB is large for standard plot sizes, averaging 46.3% for 0.1 ha subplots and 16.6% for 1 ha subplots. Topographically heterogeneous sites showed positive spatial autocorrelation in AGB at scales of 100m and above; at smaller scales, most study sites showed negative or nonexistent spatial autocorrelation in AGB. We further show that when field calibration plots are smaller than the remote sensing pixels, the high local spatial variability in AGB leads to a substantial “dilution” bias in calibration parameters, a bias that cannot be removed with current statistical methods. Overall, our results suggest that topography should be explicitly accounted for in future sampling strategies and that much care must be taken in designing calibration schemes if remote sensing of forest carbon is to achieve its promise

Iron status and Helicobacter pylori infection in symptomatic children: an international multi-centered study

Objective:Iron deficiency (ID) and iron deficiency anaemia (IDA) are global major public health problems, particularly in developing countries. Whilst an association between H. pylori infection and ID/IDA has been proposed in the literature, currently there is no consensus. We studied the effects of H. pylori infection on ID/IDA in a cohort of children undergoing upper gastrointestinal endoscopy for upper abdominal pain in two developing and one developed country.Methods:In total 311 children (mean age 10.7±3.2 years) from Latin America - Belo Horizonte/Brazil (n = 125), Santiago/Chile (n = 105) - and London/UK (n = 81), were studied. Gastric and duodenal biopsies were obtained for evaluation of histology and H. pylori status and blood samples for parameters of ID/IDA.Results:The prevalence of H. pylori infection was 27.7% being significantly higher (p<0.001) in Latin America (35%) than in UK (7%). Multiple linear regression models revealed H. pylori infection as a significant predictor of low ferritin and haemoglobin concentrations in children from Latin-America. A negative correlation was observed between MCV (r = -0.26; p = 0.01) and MCH (r = -0.27; p = 0.01) values and the degree of antral chronic inflammation, and between MCH and the degree of corpus chronic (r = -0.29, p = 0.008) and active (r = -0.27, p = 0.002) inflammation.Conclusions:This study demonstrates that H. pylori infection in children influences the serum ferritin and haemoglobin concentrations, markers of early depletion of iron stores and anaemia respectively

Local hydrological conditions influence tree diversity and composition across the Amazon basin

Tree diversity and composition in Amazonia are known to be strongly determined by the water supplied by precipitation. Nevertheless, within the same climatic regime, water availability is modulated by local topography and soil characteristics (hereafter referred to as local hydrological conditions), varying from saturated and poorly drained to well-drained and potentially dry areas. While these conditions may be expected to influence species distribution, the impacts of local hydrological conditions on tree diversity and composition remain poorly understood at the whole Amazon basin scale. Using a dataset of 443 1-ha non-flooded forest plots distributed across the basin, we investigate how local hydrological conditions influence 1) tree alpha diversity, 2) the community-weighted wood density mean (CWM-wd) – a proxy for hydraulic resistance and 3) tree species composition. We find that the effect of local hydrological conditions on tree diversity depends on climate, being more evident in wetter forests, where diversity increases towards locations with well-drained soils. CWM-wd increased towards better drained soils in Southern and Western Amazonia. Tree species composition changed along local soil hydrological gradients in Central-Eastern, Western and Southern Amazonia, and those changes were correlated with changes in the mean wood density of plots. Our results suggest that local hydrological gradients filter species, influencing the diversity and composition of Amazonian forests. Overall, this study shows that the effect of local hydrological conditions is pervasive, extending over wide Amazonian regions, and reinforces the importance of accounting for local topography and hydrology to better understand the likely response and resilience of forests to increased frequency of extreme climate events and rising temperatures

Estimating the global conservation status of more than 15,000 Amazonian tree species

Estimates of extinction risk for Amazonian plant and animal species are rare and not often incorporated into land-use policy and conservation planning. We overlay spatial distribution models with historical and projected deforestation to show that at least 36% and up to 57% of all Amazonian tree species are likely to qualify as globally threatened under International Union for Conservation of Nature (IUCN) Red List criteria. If confirmed, these results would increase the number of threatened plant species on Earth by 22%. We show that the trends observed in Amazonia apply to trees throughout the tropics, and we predict thatmost of the world’s >40,000 tropical tree species now qualify as globally threatened. A gap analysis suggests that existing Amazonian protected areas and indigenous territories will protect viable populations of most threatened species if these areas suffer no further degradation, highlighting the key roles that protected areas, indigenous peoples, and improved governance can play in preventing large-scale extinctions in the tropics in this century