Publications by authors named "Henrique Marques Souza"

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the agent of a major global outbreak of respiratory tract disease known as Coronavirus Disease 2019 (COVID-19). SARS-CoV-2 infects mainly lungs and may cause several immune-related complications, such as lymphocytopenia and cytokine storm, which are associated with the severity of the disease and predict mortality. The mechanism by which SARS-CoV-2 infection may result in immune system dysfunction is still not fully understood.

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The COVID-19 (Coronavirus Disease 2019), caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), severely affects mainly individuals with pre-existing comorbidities. Here our aim was to correlate the mTOR (mammalian/mechanistic Target of Rapamycin) and autophagy pathways with the disease severity. Through western blotting and RNA analysis, we found increased mTOR signaling and suppression of genes related to autophagy, lysosome, and vesicle fusion in Vero E6 cells infected with SARS-CoV-2 as well as in transcriptomic data mining of bronchoalveolar epithelial cells from severe COVID-19 patients.

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Visceral adiposity is a risk factor for severe COVID-19, and a link between adipose tissue infection and disease progression has been proposed. Here we demonstrate that SARS-CoV-2 infects human adipose tissue and undergoes productive infection in fat cells. However, susceptibility to infection and the cellular response depends on the anatomical origin of the cells and the viral lineage.

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Article Synopsis
  • Hypothalamic interleukin-6 (IL6) activates the ERK1/2 pathway in the ventromedial hypothalamus, which promotes fatty acid oxidation in mouse skeletal muscle via AMPK/ACC signaling.
  • Bioinformatics analysis links the IL6/ERK1/2 pathway to fatty acid metabolism-related genes in both mice and humans, indicating its broad metabolic control.
  • The study shows that the α2-adrenergic pathway is necessary for IL6's effect on muscle metabolism, as blocking the IL6 receptor in the VMH disrupts exercise-induced fatty acid oxidation.
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  • The brine shrimp, Artemia franciscana, has a unique body structure consisting of 11 thoracic segments, 2 genital segments, and 6 abdominal segments.
  • Previous studies claimed that the Hox gene Abd-B was only expressed in the genital segments, suggesting the abdominal segments lacked this gene and were unique among crustaceans.
  • This new study found that Abd-B is initially expressed in the abdominal segments during development but later retracts to the genital segments, indicating a shared evolutionary origin for the abdominal structure in crustaceans.
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  • SARS-CoV-2, the virus causing the COVID-19 pandemic, interacts with the human protein Proliferating Cell Nuclear Antigen (PCNA), which is important for DNA repair and replication.
  • The study used several methods to confirm this interaction, finding that in infected cells, PCNA shifts from the nucleus to the cytoplasm and has increased expression levels, indicating DNA damage.
  • Targeting the PCNA-M protein interaction could be a potential therapeutic strategy for COVID-19, as inhibiting this process reduced viral plaque formation in experiments.
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We previously reported that the canonical Wnt signaling pathway is activated during compensatory islet hyperplasia in prediabetic mice. Here, we aimed to expand our knowledge concerning the Wnt signaling partners and modulators involved in this process. We report here that Axin1, Axin2, and DACT1, inhibitors of the canonical Wnt signaling pathway, displayed no change in their expression, while GSK-3β, a multi-functional kinase that acts as a negative regulator of this pathway as well as affects insulin secretion/action, was up-regulated in hyperplastic islets of prediabetic mice.

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Background: Mutations accrued by SARS-CoV-2 lineage P.1-first detected in Brazil in early January, 2021-include amino acid changes in the receptor-binding domain of the viral spike protein that also are reported in other variants of concern, including B.1.

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Regeneration is a widely spread process across the animal kingdom, including many species of marine crustaceans. It is strongly linked to hormonal cycles and, therefore, a great endpoint candidate for toxicology studies. We selected the amphipod Parhyale hawaiensis as test organism, already used in ecotoxicological studies and able to regenerate its body appendages.

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Microbiota-derived molecules called short-chain fatty acids (SCFAs) play a key role in the maintenance of the intestinal barrier and regulation of immune response during infectious conditions. Recent reports indicate that SARS-CoV-2 infection changes microbiota and SCFAs production. However, the relevance of this effect is unknown.

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Mammalian embryogenesis is a paradigm of regulative development as mouse embryos show plasticity in the regulation of cell fate, cell number, and tissue morphogenesis. However, the mechanisms behind embryo plasticity remain largely unknown. Here, we determine how mouse embryos respond to an increase in cell numbers to regulate the timing and mechanism of embryonic morphogenesis, leading to the formation of the pro-amniotic cavity.

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Analysis of the transcriptome of organisms exposed to toxicants offers new insights for ecotoxicology, but further research is needed to enhance interpretation of results and effectively incorporate them into useful environmental risk assessments. Factors that must be clarified to improve use of transcriptomics include assessment of the effect of organism sex within the context of toxicant exposure. Amphipods are well recognized as model organisms for toxicity evaluation because of their sensitivity and amenability to laboratory conditions.

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Article Synopsis
  • - RNA interference (RNAi) is a gene-silencing technique that uses double-stranded RNA to target specific gene sequences, which is proving useful for pest control in agriculture, particularly with insect pests like the tomato leafminer.
  • - Researchers focused on two specific genes from the tomato leafminer and tested two methods to deliver the target dsRNA into tomato leaves, successfully silencing these genes and decreasing larval survival rates and leaf damage.
  • - They created genetically modified 'Micro-Tom' tomato plants that expressed hairpin RNA sequences targeting the selected genes, resulting in reduced leaf damage caused by the leafminer, demonstrating RNAi's potential as a pest control strategy.
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  • Researchers are studying the use of double-stranded RNA (dsRNA) to silence genes in the tomato leafminer, a pest causing severe crop damage in Europe, as a way to improve pest control through RNA interference (RNAi).
  • They sequenced RNA samples from different life stages of Tuta absoluta, resulting in a comprehensive transcriptome with nearly 93,500 gene sequences, allowing for the identification of critical genes linked to insect development and potential RNAi targets.
  • Experiments showed that feeding specific dsRNA to young T. absoluta larvae significantly reduced their body weight and effectively silenced three targeted genes, indicating the feasibility of using RNAi for pest management.
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The identification of subpharyngeal cardiac precursors has had a strong influence on the way we think about early cardiac development. From this discovery was born the concept of multiple heart fields. Early support for the concept came from gene expression, genetic retrospective fate mapping, and gene targeting studies, which collectively suggested the existence of a second heart field (SHF) on the basis of specific Islet-1 (Isl-1) expression, presence of two cardiac ancestral lineages, and compatible cardiac knockout phenotypes, respectively.

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Hairy stripes in Tribolium are generated during blastoderm and germ band extension, but a direct role for Tc-h in trunk segmentation was not found. We have studied here several aspects of hairy function and expression in Tribolium, to further elucidate its role. First, we show that there is no functional redundancy with other hairy paralogues in Tribolium.

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Tribolium castaneum is a member of the most species-rich eukaryotic order, a powerful model organism for the study of generalized insect development, and an important pest of stored agricultural products. We describe its genome sequence here. This omnivorous beetle has evolved the ability to interact with a diverse chemical environment, as shown by large expansions in odorant and gustatory receptors, as well as P450 and other detoxification enzymes.

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The gap gene hunchback in Drosophila acts during syncytial blastoderm stage via a short-range gradient and concentration-dependent activation or repression of target genes. Orthologues of hunchback can be easily found in other insects, but it has been unclear how well its functions are conserved. The segmentation process in most insect embryos occurs under cellular conditions, which should not allow the formation of diffusion-controlled transcription factor gradients.

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Segmentation genes in insects are required for generating the subdivisions of the early embryo. We describe here a new member of the gap family of segmentation genes in the flour beetle Tribolium, mille-pattes (mlpt). mlpt knockdown leads to transformation of the abdominal segments into thoracic segments, providing embryos with up to ten pairs of legs.

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