Publications by authors named "Rui Neves"

Background: Circulating tumour cells (CTCs) and tumour-derived extracellular vesicles (tdEVs) have great potential for monitoring therapy response and early detection of tumour relapse, facilitating personalized adjuvant therapeutic strategies. However, their low abundance in peripheral blood limits their informative value. In this study, we explored the presence of CTCs and tdEVs collected intraoperatively from a tumour-draining vein (DV) and via a central venous catheter (CVC) prior to tumour resection.

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Machine learning (ML) is transforming the investigation of complex biological processes. In enzymatic catalysis, one significant challenge is identifying the reactive conformations (RC) of the enzyme:substrate complex where the substrate assumes a precise arrangement in the active site necessary to initiate a reaction. Traditional methods are hindered by the complexity of the multidimensional free energy landscape involved in the transition from nonreactive to reactive conformations.

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Article Synopsis
  • - PARP inhibitors show promise in treating castration-resistant prostate cancer (CRPC) with homologous recombination repair (HRR) defects, but the reasons behind resistance are not completely understood.
  • - A study from the TOPARP-B trial found that 79% of BRCA2/PALB2-mutated tumors exhibited reversion mutations at the end of treatment, with many related to POLQ-mediated DNA repair mechanisms.
  • - In cases of BRCA2 homozygous deletions, rare subclones lacking the BRCA2 deletion are selected for after PARP inhibitor treatment, indicating the necessity for restored HRR function in developing resistance.
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This narrative review aims to provide a comprehensive overview of the current state of circulating tumor cell (CTC) analysis and its clinical significance in patients with epithelial cancers. The review explores the advancements in CTC detection methods, their clinical applications, and the challenges that lie ahead. By examining the important research findings in this field, this review offers the reader a solid foundation to understand the evolving landscape of CTC analysis and its potential implications for clinical practice.

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Article Synopsis
  • Regulations require ultralow sulfur levels in fossil fuels, especially diesel, due to health and environmental concerns, but current desulfurization methods are costly and ineffective against certain sulfur compounds.
  • Biodesulfurization using the 4S pathway from a specific bacterium offers a potential solution, although its enzymes, particularly DszA, need to work significantly faster for practical industrial use.
  • This research uncovers the unique catalytic mechanism of the enzyme DszA, revealing a specific chemical process that could aid in improving its efficiency, making biodesulfurization a more viable option for the oil refining sector.*
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The limited sensitivity of circulating tumor cell (CTC) detection in pancreatic adenocarcinoma (PDAC) stems from their extremely low concentration in the whole circulating blood, necessitating enhanced detection methodologies. This study sought to amplify assay-sensitivity by employing diagnostic leukapheresis (DLA) to screen large blood volumes. Sixty patients were subjected to DLA, with a median processed blood volume of ~ 2.

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We describe an approach to identify enzyme mutants with increased turnover using the enzyme DszC as a case study. Our approach is based on recalculating the barriers of alanine mutants through single-point energy calculations at the hybrid QM/MM level in the wild-type reactant and transition state geometries. We analyze the difference in the electron density between the reactant and transition state to identify sites/residues where electrostatic interactions stabilize the transition state over the reactants.

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Hydrolysis of lignocellulosic biomass, composed of a lignin-carbohydrate-complex (LCC) matrix, is critical for producing bioethanol from glucose. However, current methods for LCC processing require costly and polluting processes. The fungal Thermothelomyces thermophila glucuronoyl esterase (TtGE) is a promising thermophilic enzyme that hydrolyses LCC ester bonds.

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We assessed enzyme:substrate conformational dynamics and the rate-limiting glycosylation step of a human pancreatic α-amylase:maltopentose complex. Microsecond molecular dynamics simulations suggested that the distance of the catalytic Asp197 nucleophile to the anomeric carbon of the buried glucoside is responsible for most of the enzyme active site fluctuations and that both Asp197 and Asp300 interact the most with the buried glucoside unit. The buried glucoside binds either in a chair or skew conformations, both of which can change to TS-like conformations characteristic of retaining glucosidases.

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The influence of the dynamical flexibility of enzymes on reaction mechanisms is a cornerstone in biological sciences. In this study, we aim to 1) study the convergence of the activation free energy by using the first step of the reaction catalysed by HIV-1 protease as a case study, and 2) provide further evidence for a mechanistic divergence in this enzyme, as two different reaction pathways were seen to contribute to this step. We used quantum mechanics/molecular mechanics molecular dynamics simulations, on four different initial conformations that led to different barriers in a previous study.

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We employed QM/MM molecular dynamics (MD) simulations to characterize the rate-limiting step of the glycosylation reaction of pancreatic α-amylase with combined DFT/molecular dynamics methods (PBE/def2-SVP : AMBER). Upon careful choice of four starting active site conformations based on thorough reactivity criteria, Gibbs energy profiles were calculated with umbrella sampling simulations within a statistical convergence of 1-2 kcal ⋅ mol . Nevertheless, Gibbs activation barriers and reaction energies still varied from 11.

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Guidance about treatment-resistant depression (TRD) in Portugal is very limited, even though depression prevalence is among the highest in European countries. A questionnaire was conducted, followed by two advisory boards with seven Portuguese psychiatry experts, to characterize and discuss MDD and TRD epidemiology, diagnosis, patient journey, treatment options, and unmet clinical needs. Consensus was reached on the main issues.

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Several global high-resolution built-up surface products have emerged over the last five years, taking full advantage of open sources of satellite data such as Landsat and Sentinel. However, these data sets require validation that is independent of the producers of these products. To fill this gap, we designed a validation sample set of 50 K locations using a stratified sampling approach independent of any existing global built-up surface products.

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Considering the limited information on the biology and molecular characteristics of disseminated tumor cells (DTCs) in head and neck squamous cell carcinoma (HNSCC), we examined the genomic alterations in DTCs from HNSCCs and their potential clinical relevance. To analyze both the lymphatic and hematogenous routes of tumor cell dissemination, we investigated samples from lymph nodes (LNs) and bone marrow (BM) of 49 patients using immunofluorescence double staining for epithelial cells expressing cytokeratin 18 (KRT18) and/or epithelial cell adhesion molecules (EpCAM, CD326). The identified marker-positive cells were isolated by micromanipulation followed by single-cell whole-genome amplification and metaphase-based comparative genomic hybridization (mCGH) to determine genome-wide copy number alterations.

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Pulmonary rehabilitation is based on a thorough patient assessment, including peripheral oxygen saturation (SpO) and heart rate (HR) at rest and on exertion. To understand whether exercise-field tests identify patients who desaturate (SpO < 90%) during physical activities, this study compared the six-minute walk test (6MWT) and daily-life telemonitoring. Cross-sectional study including 100 patients referred for pulmonary rehabilitation.

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In Ovarian Cancer (OC), the analysis of single circulating tumor cells (sCTCs) might help to investigate genetic tumor evolution during the course of treatment. Since common CTC identification features failed to reliably detect CTCs in OC, we here present a workflow for their detection and genomic analysis. Blood of 13 high-grade serous primary OC patients was analyzed, using negative immunomagnetic enrichment, followed by immunofluorescence staining and imaging for Hoechst, ERCC1, CD45, CD11b and cytokeratin (CK) and sCTC sorting with the DEPArray NxT.

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Fatty acids are crucial molecules for most living beings, very well spread and conserved across species. These molecules play a role in energy storage, cell membrane architecture, and cell signaling, the latter through their derivative metabolites. synthesis of fatty acids is a complex chemical process that can be achieved either by a metabolic pathway built by a sequence of individual enzymes, such as in most bacteria, or by a single, large multi-enzyme, which incorporates all the chemical capabilities of the metabolic pathway, such as in animals and fungi, and in some bacteria.

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Background: Circulating tumour cell (CTC)-derived organoids have the potential to provide a powerful tool for personalised cancer therapy but are restrained by low CTC numbers provided by blood samples. Here, we used diagnostic leukapheresis (DLA) to enrich CTCs from patients with metastatic prostate cancer (mPCa) and explored whether organoids provide a platform for ex vivo treatment modelling.

Methods: We prospectively screened 102 patients with mPCa and performed DLA in 40 patients with ≥5 CTCs/7.

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Women are exposed to increased burden of mental disorders during the perinatal period: 13-19% experience postpartum depression. Perinatal psychological suffering affects early mother-child relationship, impacting child's emotional and cognitive development. Return-to-work brings additional vulnerability given the required balance between parenting and job demands.

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Background: Multiple technologies are available for detection of circulating tumor cells (CTCs), but standards to evaluate their technical performance are still lacking. This limits the applicability of CTC analysis in clinic routine. Therefore, in the context of the CANCER-ID consortium, we established a platform to assess technical validity of CTC detection methods in a European multi-center setting using non-small cell lung cancer (NSCLC) as a model.

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Novel pharmacological strategies for the treatment of diabetic patients are now focusing on inhibiting glycogenolysis steps. In this regard, glycogen phosphorylase (GP) is a validated target for the discovery of innovative antihyperglycemic molecules. Natural products, and in particular flavonoids, have been reported as potent inhibitors of GP at the cellular level.

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Bacterial glycosyltransferases of the GT51 family are key enzymes in bacterial cell wall synthesis. Inhibiting cell wall synthesis is a very effective approach for development of antibiotics, as this can lead to either bacteriostatic or bactericidal effects. Even though the existence of this family has been known for over 50 years, only one potent inhibitor exists, which is an analog of the lipid IV product and derived from a natural product.

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Physical inactivity may be a consequence of chronic diseases but also a potential modifiable risk factor. Therefore, it should be clinically assessed as a vital sign of patients' general physical condition prior to any exercise-based intervention. This cross-sectional study describes physical activity in the daily life of 100 chronic respiratory patients before pulmonary rehabilitation, comparing subjective and objective measures.

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