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Este ensaio propõe uma leitura da primeira obra poética de Ruy Belo (1933-1978), Aquele Grande Rio Eufrates, publicada em 1961 e seguida onze anos depois da segunda edição, já com alterações assinaláveis, a partir de três termoschave que anuncia no prefácio que redigiu em 1972: a solidão do sujeito, a cidade e, como enquadramento privilegiado dos anteriores, a reflexão sobre o tempo, presente neste livro em versões como as de crise ou quotidiano. A partir destes tópicos e de exemplos de poemas da obra referida, procura-se neste trabalho a indagação da importância dos sinais ou vestigia da memória transportada pela palavra poética e de que modo a atitude de avistamento desses residua por parte do sujeito lírico permite sustentar as tensões entre as representações do real e o seu processo criativo

This case refers to a 39-year-old woman with hypertrophic cardiomyopathy (HCM) and family history of sudden death (SD). In 1985, high rate atrial stimulation induced VF. In 1996 an ICD was implanted and she remained without arrhythmic events until November 2000 when the device reported one episode of atrial fibrillation degenerating into VF and terminated by the ICD. The VF induction mechanism recorded by the ICD was similar to that observed in 1985. The high incidence of atrial tachyarrhythmias in HCM renders cases like this at higher risk of SD. The predictive role of incremental atrial stimulation merits highlighting in future studies. [ABSTRACT FROM AUTHOR]

The study concerned technical feasibility, economic profitability, and carbon footprint (CF) analysis of semi-continuous anaerobic digestion (sAD) of organic fraction of municipal solid waste (OFMSW). The research assessed the pre-treatment effect on sAD by varying organic loading rates (OLR) from 3.38 to 6.75 kgvs/m 3 d. Three sAD configurations were investigated: hydrodynamic-cavitated (HC-OFMSW), enzymatically pre-treated (EN-OFMSW), and non-pre-treated (AD-OFMSW). Principal Component Analysis and Supervised Kohonen's Self-Organizing Maps combined the experimental, economic, and environmental evaluations. The sAD configurations were grouped predominantly according to the OLR however, within each OLR group the configurations were clustered according to the pre-treatments. The finding highlighted that pre-treatments offset inhibition in sAD of OFMSW due to the OLR increase, being economically profitable and CF negative up to 4.50 kgvs/m 3 d for EN-OFMSW and to 5.40 kgvs/m 3 d for HC-OFMSW. Whereas sAD-OFMSW remained economically and environmentally viable only up to 3.87 kgvs/m 3 d. HC-OFMSW reached the highest performance. In detail, for HC-OFMSW the NPV and CF ranged from 17679.30 to 43827.12 euros and from -51.08 to -407.210 kg CO 2 eq/1 MWh daily produced, by decreasing the OLR from 5.40 to 3.87 kgvs/m 3 d. These results are fundamental since pre-treatment is usually expensive due to additional energy or chemical requirements., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Extremely high temperatures, which negatively affect the human health and plant performances, are becoming more frequent in cities. Urban green infrastructure, particularly trees, can mitigate this issue through cooling due to transpiration, and shading. Temperature regulation by trees depends on feedbacks among the climate, water supply, and plant physiology. However, in contrast to forest or general ecosystem models, most current urban tree models still lack basic processes, such as the consideration of soil water limitation, or have not been evaluated sufficiently. In this study, we present a new model that couples the soil water balance with energy calculations to assess the physiological responses and microclimate effects of a common urban street-tree species (Tilia cordata Mill.) on temperature regulation. We contrast two urban sites in Munich, Germany, with different degree of surface sealing at which microclimate and transpiration had been measured. Simulations indicate that differences in wind speed and soil water supply can be made responsible for the differences in transpiration. Nevertheless, the calculation of the overall energy balance showed that the shading effect, which depends on the leaf area index and canopy cover, contributes the most to the temperature reduction at midday. Finally, we demonstrate that the consideration of soil water availability for stomatal conductance has realistic impacts on the calculation of gaseous pollutant uptake (e.g., ozone). In conclusion, the presented model has demonstrated its ability to quantify two major ecosystem services (temperature mitigation and air pollution removal) consistently in dependence on meteorological and site conditions.

Prolactin (PRL) is a hormone principally secreted by lactotrophs of the anterior pituitary gland. Although the synthesis and exocytosis of this hormone are mainly under the regulation of hypothalamic dopamine (DA), the possibility that the anterior pituitary synthesises this catecholamine remains unclear. The present study aimed to determine if the anterior pituitary produces DA from the precursor l-3,4-dihydroxyphenylalanine (l-dopa). Accordingly, we investigated the expression of aromatic l-amino acid decarboxylase (AADC) enzyme and the transporter vesicular monoamine transporter 2 (VMAT2) in the anterior pituitary, AtT20 and GH3 cells by immunofluorescence and western blotting. Moreover, we investigated the production of DA from l-dopa and its release in vitro. Then, we explored the effects of l-dopa with respect to the secretion of PRL from anterior pituitary fragments. We observed that the anterior pituitary, AtT20 and GH3 cells express both AADC and VMAT2. Next, we detected an increase in DA content after anterior pituitary fragments were incubated with l-dopa. Also, the presence of l-dopa increased DA levels in incubation media and reduced PRL secretion. Likewise, the content of cellular DA increased after AtT20 cells were incubated with l-dopa. In addition, l-dopa reduced corticotrophin-releasing hormone-stimulated adrenocorticotrophic hormone release from these cells after AADC activity was inhibited by NSD-1015. Moreover, DA formation from l-dopa increased apoptosis and decreased proliferation. However, in the presence of NSD-1015, l-dopa decreased apoptosis and increased proliferation rates. These results suggest that the anterior pituitary synthesises DA from l-dopa by AADC and this catecholamine can be released from this gland contributing to the control of PRL secretion. In addition, our results suggest that l-dopa exerts direct actions independently from its metabolisation to DA., (© 2020 British Society for Neuroendocrinology.)

Acetaminophen (APAP) administration at therapeutic doses is safe, however overdosing produces hepatocellular injury via a multifactorial mechanism(s) that involves generation of reactive oxygen species (ROS), being the most common cause of acute liver failure (ALF) in the northern hemisphere. Brain alterations induced by APAP intoxication are usually considered secondary to hepatic encephalopathy development due to ALF. Although APAP is primarily metabolized in the liver, it is also distributed and metabolized homogeneously in the brain, affecting brain redox status. Nevertheless, comprehensive studies on the potential of APAP intoxication to produce brain toxicity are scarce. The aim of this study was to characterize the direct toxic effects of APAP in different regions of the brain and on behavior in rats where the magnitude of hepatotoxicity produced is not associated with ALF. The present work demonstrates that APAP intoxication producing hepatotoxicity, but not ALF in rats, is associated with marked hypolocomotion. Our studies also suggest that selective downregulation in dopamine levels in brain areas that regulate motor activity may be responsible, in part, for the decreased locomotion observed with APAP treatment. Furthermore, we observed that the brain histoarchitecture is conserved and that edema is not present. However, an increase in oxidative stress, reactive astrogliosis and a decrease in neuron processes are the main features observed in APAP-intoxicated animals. These effects might be partly due to direct toxic effects of APAP in brain, since the same reactive astrogliosis observed in rats was also observed in rat primary astrocyte cultures exposed to APAP., (Copyright © 2019. Published by Elsevier Inc.)

Membrane progesterone receptors are known to mediate rapid nongenomic progesterone effects in different cell types. Recent evidence revealed that mPRα is highly expressed in the rat pituitary, being primarily localized in lactotrophs, acting as an intermediary of P4-inhibitory actions on prolactin secretion. The role of mPRs in prolactinoma development remains unclear. We hypothesize that mPR agonists represent a novel tool for hyperprolactinemia treatment. To this end, pituitary expression of mPRs was studied in three animal models of prolactinoma. Expression of mPRs and nuclear receptor was significantly decreased in tumoral pituitaries compared to normal ones. However, the relative proportion of mPRα and mPRβ was highly increased in prolactinomas. Interestingly, the selective mPR agonist (Org OD 02-0) significantly inhibited PRL release in both normal and tumoral pituitary explants, displaying a more pronounced effect in tumoral tissues. As P4 also regulates PRL secretion indirectly, by acting on dopaminergic neurons, we studied mPR involvement in this effect. We found that the hypothalamus has a high expression of mPRs. Interestingly, both P4 and OrgOD 02-0 increased dopamine release in hypothalamus explants. Moreover, in an in vivo treatment, that allows both, pituitary and hypothalamus actions, the mPR agonist strongly reduced the hyperprolactinemia in transgenic females carrying prolactinoma. Finally, we also found and interesting gender difference: males express higher levels of pituitary mPRα/β, a sex that does not develop prolactinoma in these mice models. Taken together, these findings suggest mPRs activation could represent a novel tool for hyperprolactinemic patients, especially those that present resistance to dopaminergic drugs.

Excessive dopamine neurotransmission underlies psychotic episodes as observed in patients with some types of bipolar disorder and schizophrenia. The dopaminergic hypothesis was postulated after the finding that antipsychotics were effective to halt increased dopamine tone. However, there is little evidence for dysfunction within the dopaminergic system itself. Alternatively, it has been proposed that excessive afferent activity onto ventral tegmental area dopaminergic neurons, particularly from the ventral hippocampus, increase dopamine neurotransmission, leading to psychosis. Here, we show that selective dopamine D 2 receptor deletion from parvalbumin interneurons in mouse causes an impaired inhibitory activity in the ventral hippocampus and a dysregulated dopaminergic system. Conditional mutant animals show adult onset of schizophrenia-like behaviors and molecular, cellular, and physiological endophenotypes as previously described from postmortem brain studies of patients with schizophrenia. Our findings show that dopamine D 2 receptor expression on parvalbumin interneurons is required to modulate and limit pyramidal neuron activity, which may prevent the dysregulation of the dopaminergic system., Competing Interests: The authors declare no conflict of interest.

Female transgenic mice that overexpress the human chorionic gonadotrophin β subunit (hCGβ+) develop prolactinomas, whereas hCGβ+ males do not. The high levels of circulating hCG induce massive luteinization in the ovary of hCGβ+ females, and progesterone becomes the primary steroid hormone produced, but estradiol remains at physiological level. The involvement of high levels of progesterone in lactotroph proliferation is not clearly understood; hence, the pathogenesis of prolactinomas in hCGβ+ females remains unclear. TGFβ1 is an inhibitor of lactotroph function, and the reduced TGFβ1 activity found in prolactinomas has been proposed to be involved in tumor development. The aim of the present work was to study the role of TGFβ1 in the gender-specific development of prolactinomas in hCGβ+ mice. We compared the expression of different components of the pituitary TGFβ1 system in males and females in this model. We found reduced TGFβ1 levels, reduced expression of TGFβ1 target genes, TGFβ1 receptors, Ltbp1 , Smad4 and Smad7 in hCGβ+ female pituitaries. However, no differences were found between the transgenic and wild-type male pituitaries. We postulate that decreased pituitary TGFβ1 activity in hCGβ+ females is involved in the development of prolactinomas. In fact, we demonstrated that an in vivo treatment carried out for increasing pituitary TGFβ1 activity, was successful in reducing the prolactinoma development, and the hyperprolactinemia in hCGβ+ females. Moreover, the stronger TGFβ1 system found in males could protect them from excessive lactotroph proliferation. Sex differences in the regulation of the pituitary TGFβ1 system could explain gender differences in the incidence of prolactinoma., (© 2017 Society for Endocrinology.)

Intraflagellar transport (IFT) is responsible for the bidirectional trafficking of molecular components required for the elongation and maintenance of eukaryotic cilia and flagella. Cargo is transported by IFT 'trains', linear rows of multiprotein particles moved by molecular motors along the axonemal doublets. We have previously described two structurally distinct categories of 'long' and 'short' trains. Here, we analyse the relative number of these trains throughout flagellar regeneration and show that long trains are most abundant at the beginning of flagellar growth whereas short trains gradually increase in number as flagella elongate. These observations are incompatible with the previous hypothesis that short trains are derived solely from the reorganization of long trains at the flagellar tip. We demonstrate with electron tomography the existence of two distinct ultrastructural organizations for the short trains, we name these 'narrow' and 'wide', and provide the first 3D model of the narrow short trains. These trains are characterized by tri-lobed units, which repeat longitudinally every 16 nm and contact protofilament 7 of the B-tubule. Functional implications of the new structural evidence are discussed., (© 2016. Published by The Company of Biologists Ltd.)