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- 0-3D Design methodPublication . Baptista, A. J.; Reis, L.; Leite, M.; DEMI - Departamento de Engenharia Mecânica e Industrial; UNIDEMI - Unidade de Investigação e Desenvolvimento em Engenharia Mecânica e Industrial; ElsevierDesign complexity and its relation to Design for Manufacturing continues to be a challenging topic, namely when the objective is to address these aspects in a straightforward manner to young or less experienced design teams. The availability of practical methodologies that induce rules to support novel design creation, in the environment of manufacturing processes, continues to be scarce. This work presents a novel approach named - 0-3D Design Method - that aims to define, in a systematic and geometrical manner, practical rules that allows mechanical designers to relate, in a codified manner, the design geometry of a given mechanical component to the typical manufacturing processes that permit its physical embodiment. The method proposes the definition of types and sub-types of parts, based on the number of spatial dimensions that need to be modified for a given design construction, and its relation to the manufacturing phase of the product life-cycle. A practical mechanical design example is presented to demonstrate the methodology, mapping the parts necessary for the design of a cutting head of a machine-tool.
- 1,2,4-Trioxolane and 1,2,4,5-Tetraoxane Endoperoxides against Old-World Leishmania ParasitesPublication . Mendes, Andreia; Armada, Ana; Cabral, Lília I.L.; Amado, Patrícia S.M.; Campino, Lenea; Cristiano, Maria L.S.; Cortes, Sofia; Instituto de Higiene e Medicina Tropical (IHMT); Global Health and Tropical Medicine (GHTM); Molecular Diversity Preservation International (MDPI)Leishmaniasis remains one of the ten Neglected Tropical Diseases with significant morbid-ity and mortality in humans. Current treatment of visceral leishmaniasis is difficult due to a lack of effective, non-toxic, and non-extensive medications. This study aimed to evaluate the selectivity of 12 synthetic endoperoxides (1,2,4-trioxolanes; 1,2,4,5-tetraoxanes) and uncover their biochemical effects on Leishmania parasites responsible for visceral leishmaniasis. The compounds were screened for in vitro activity against L. infantum and L. donovani and for cytotoxicity in two monocytic cell lines (J774A.1 and THP-1) using the methyl thiazol tetrazolium assay. Reactive oxygen species formation, apoptosis, and mitochondrial impairment were measured by flow cytometry. The compounds exhib-ited fair to moderate anti-proliferative activity against promastigotes of the 2 Leishmania species, with IC50 values ranging from 13.0 ± 1.7 µM to 793.0 ± 37.2 µM. Tetraoxanes LC132 and LC138 demonstrated good leishmanicidal activity on L. infantum amastigotes (IC50 13.2 ± 5.2 and 23.9 ± 2.7 µM) with low cytotoxicity in mammalian cells (SIs 22.1 and 118.6), indicating selectivity towards the parasite. Furthermore, LC138 was able to induce late apoptosis and dose-dependent oxidative stress without affecting mithocondria. Compounds LC132 and LC138 can be further explored as potential antileishmanial chemotypes.
- 1,4-disubstituted-1,2,3-triazole compounds induce ultrastructural alterations in leishmania amazonensis promastigote: An in vitro antileishmanial and in silico pharmacokinetic studyPublication . Almeida-Souza, Fernando; da Silva, Verônica Diniz; Silva, Gabriel Xavier; Taniwaki, Noemi Nosomi; Hardoim, Daiana de Jesus; Buarque, Camilla Djenne; Abreu-Silva, Ana Lucia; Calabrese, Kátia da Silva; DQ - Departamento de Química; MDPI - Multidisciplinary Digital Publishing InstituteThe current standard treatment for leishmaniasis has remained the same for over 100 years, despite inducing several adverse effects and increasing cases of resistance. In this study we evaluated the in vitro antileishmanial activity of 1,4-disubstituted-1,2,3 triazole compounds and carried out in silico predictive study of their pharmacokinetic and toxicity properties. Ten compounds were analyzed, with compound 6 notably presenting IC50: 14.64 ± 4.392 µM against promastigotes, IC50: 17.78 ± 3.257 µM against intracellular amastigotes, CC50: 547.88 ± 3.256 µM against BALB/c peritoneal macrophages, and 30.81-fold selectivity for the parasite over the cells. It also resulted in a remarkable decrease in all the parameters of in vitro infection. Ultrastructural analysis revealed lipid corpuscles, a nucleus with discontinuity of the nuclear membrane, a change in nuclear chromatin, and kinetoplast swelling with breakdown of the mitochondrial cristae and electron-density loss induced by 1,4-disubstituted-1,2,3-triazole treatment. In addition, compound 6 enhanced 2.3-fold the nitrite levels in the Leishmania-stimulated macrophages. In silico pharmacokinetic prediction of compound 6 revealed that it is not recommended for topical formulation cutaneous leishmaniasis treatment, however the other properties exhibited results that were similar or even better than miltefosine, making it a good candidate for further in vivo studies against Leishmania parasites.
- 1-Year of COVID-19 pandemicPublication . Neiva-Sousa, Manuel; Mateus, Cátia; De Oliveira, Pedro Gomes; Bouca, Alexandre; Da Silva, Luis Nunes; Valejo-Coelho, Paulo; NOVA Medical School|Faculdade de Ciências Médicas (NMS|FCM); Ediciones Ergon SAObjectives: Due to COVID-19 pandemic, social distancing policies were enacted worldwide, including by the Portuguese official authorities. However, the impact of these measures on maxillofacial trauma and fracture surgical repair remains poorly understood. The aim of this study was to evaluate and compare the incidence and aetiology of facial fractures submitted to surgical repair during 1-year of COVID-19 pandemic versus the previous 4 years, in a level III Trauma Centre located in Lisbon, Portugal. Materials and methods: All emergency episodes registered in our hospital between March 2016 and February 2021 that resulted in patient admittance for surgical treatment of facial fracture were included. Comparative analysis was performed for variables such as fracture type and aetiology. Results: Analysis showed that surgeries performed during the 1st year of COVID-19 were reduced by 37.5 %. Considering only the 75-day lockdown period at the beginning of the pandemic, reduction was even more pronounced and reached-66.7 %. Significant differences in the aetiology were also found, with physical assault and sport accidents relative frequency decreasing. Moreover, despite being systematically the second most common cause of fracture, during lockdown, fall ranked first, over physical assault. The relative frequency of nasal fractures, the most common facial fracture treated in our hospital, decreased during both the 1st year of COVID-19 and the lockdown period, while mandible fractures ranked first during lockdown. Conclusions: Our study shows that COVID-19 pandemic and enacted policies have significantly changed the epidemiology of maxillofacial trauma.
- 1-Year Outcomes of Novel Balloon-Expandable vs Contemporary Transcatheter Heart Valves in Severe Aortic StenosisPublication . Serruys, Patrick W.; Tobe, Akihiro; van Royen, Niels; Amat-Santos, Ignacio J.; Hudec, Martin; Bunc, Matjaz; Van den Branden, Ben J.L.; Laanmets, Peep; Unic, Daniel; Merkely, Bela; Hermanides, Renicus S.; Ninios, Vlasis; Protasiewicz, Marcin; Rensing, Benno J.W.M.; Martin, Pedro L.; Feres, Fausto; De Sousa Almeida, Manuel; van Belle, Eric; Linke, Axel; Ielasi, Alfonso; Montorfano, Matteo; Webster, Mark; Toutouzas, Konstantinos; Teiger, Emmanuel; Bedogni, Francesco; Voskuil, Michiel; Pan, Manuel; Angerås, Oskar; Kim, Won Keun; Rothe, Jürgen; Abdel-Wahab, Mohamed; Kristić, Ivica; Peral, Vicente; Garg, Scot; Tsai, Tsung Ying; Thakkar, Ashokkumar; Chandra, Udita; Smits, Pieter C.; Morice, Marie Claude; Onuma, Yoshinobu; Baumbach, Andreas; NOVA Medical School|Faculdade de Ciências Médicas (NMS|FCM); Comprehensive Health Research Centre (CHRC) - pólo NMS; Elsevier Science Publisher B.V.Background: In the LANDMARK trial, the Myval balloon-expandable transcatheter heart valve (THV) series was noninferior to the most commonly used contemporary SAPIEN and Evolut Series THVs for the 30-day early safety endpoint in participants with symptomatic severe native aortic stenosis. Objectives: The current report from the LANDMARK trial describes clinical outcomes, hemodynamic performances, and quality of life at 1 year. Methods: This open-label, noninferiority trial enrolled 768 participants across 31 hospitals in Europe, New Zealand, and Brazil. Participants were randomly assigned (1:1) to receive either a Myval THV series or a contemporary THV (SAPIEN or Evolut series). The composite endpoint at 1 year included all-cause mortality, all strokes, and procedure- or valve-related hospitalizations. Clinical efficacy was defined as freedom from the composite endpoint. As recommended in Valve Academic Research Consortium-3, the previous composite endpoint combined with the assessment of quality of life at baseline and 1 year with the 12-Item Short Form Health Survey was reported as an extended composite endpoint. The noninferiority hypothesis was prespecified for the assessment of the primary endpoint at 30 days. Considering the specific 1-year composite endpoints of Valve Academic Research Consortium-3 and the event rate of 27.23% derived from recent studies, an a posteriori descriptive and exploratory noninferiority hypothesis was introduced with a noninferiority margin of 10.89%. The analysis was performed in the intention-to-treat population. Results: The mean age was 80 years, 48% were women, and the median Society of Thoracic Surgeons Predicted Risk of Mortality score was 2.6%. There was no significant difference in the Kaplan-Meier estimates of freedom from the composite endpoint at 365 days (Myval THV 87.0% vs contemporary THVs 86.9%). The Myval THV series was noninferior to the contemporary THVs for the composite endpoint (difference: −0.1%; 1-sided 95% CI: 3.9%; Pnoninferiority < 0.0001). Similarly, there were no significant differences in freedom from the extended composite endpoint (80.5% vs 77.3%; difference: 3.2%; 95% CI: −2.9% to 9.2%; P = 0.33). Conclusions: In the treatment of symptomatic severe native aortic stenosis, the clinical and hemodynamic outcomes of the Myval THV series were comparable to those of contemporary THVs for the 1-year composite of all-cause mortality, all strokes, or procedure- or valve-related hospitalizations.
- The 1.4 Å resolution structure of Paracoccus pantotrophus pseudoazurinPublication . Najmudin, Shabir; Pauleta, Sofia R.; Moura, Isabel; Romão, Maria J.; DQ - Departamento de Química; CQFB-REQUIMTE - Centro de Química Fina e Biotecnologia (Lab. Associado REQUIMTE); Blackwell Publishing LtdPseudoazurins are small type 1 copper proteins that are involved in the flow of electrons between various electron donors and acceptors in the bacterial periplasm, mostly under denitrifying conditions. The previously determined structure of Paracoccus pantotrophus pseudoazurin in the oxidized form was improved to a nominal resolution of 1.4 Å, with R and R free values of 0.188 and 0.206, respectively. This high-resolution structure makes it possible to analyze the interactions between the monomers and the solvent structure in detail. Analysis of the high-resolution structure revealed the structural regions that are responsible for monomer-monomer recognition during dimer formation and for protein-protein interaction and that are important for partner recognition. The pseudoazurin structure was compared with other structures of various type 1 copper proteins and these were grouped into families according to similarities in their secondary structure; this may be useful in the annotation of copper proteins in newly sequenced genomes and in the identification of novel copper proteins.
- 10 reflexões sobre o papel do médico na administração de hospitaisPublication . Ferreira, Coriolano
- 100 Years of Land-Use and Land-Cover DataPublication . Faria de Deus, Raquel; Tenedório, José António; Tenedório, José António; Pumain, Denise; Rocha, Jorge; Pereira, Margarida; Centro Interdisciplinar de Ciências Sociais (CICS.NOVA - NOVA FCSH); História, Territórios e Comunidades do Centro de Ecologia Funcional (pólo NOVA FCSH); Departamento de Geografia e Planeamento Regional (DGPR); Molecular Diversity Preservation International (MDPI)The Sustainable Development Goals require us to rethink spatial planning policies’ effectiveness. This article proposes a reproducible method for assessing the effect of past planning practices and simulating future land-use and land-cover (LULC) changes with a Cellular Automata model. The originality of our approach is to systematically compare observed changes in LULC with the planning rules in force over almost a century of evolution. A quasi-exhaustive database was constructed at a very fine spatial resolution for the municipality of Portimão (Southern Portugal), including the location and changes of LULC categories, and the planning rules of the corresponding time period on nine dates between 1947 and 2018. The quantified measurement of the actual effect of planning rules enables us to identify other determinants of the evolution. Findings reveal that the policies established by the local government—which aimed to foster well-planned comprehensive urban areas—were not as effective as intended. The quantified discrepancies between planning recommendations and observed evolution help to simulate which LULC scenarios could be designed to reach the expected result in future planning policies. Our assessment method could be applied in other urban and tourist regions where land artificialization exerts strong pressure on the environment.
- A 1000-year-old mystery solved: Unlocking the molecular structure for the medieval blue from Chrozophora tinctoria, also known as foliumPublication . Nabais, Paula; Oliveira, Joana; Pina, Fernando; Teixeira, Natércia; De Freitas, Victor; Brás, Natércia F.; Clemente, A.; Rangel, Maria; Silva, Artur M. S.; Melo, Maria João; LAQV@REQUIMTE; American Association for the Advancement of ScienceThe molecular structure of the medieval watercolor known as folium has finally been solved in the 21st century. The interdisciplinary approach taken was the key to producing extracts that had been prepared following medieval instructions, and shows the blue/purple chromophore as the major dye in Chrozophora tinctoria fruits (shell). A multi-analytical characterization of its structure was made using HPLC-DAD-MS, GC-MS, NMR (1H, 13C, COSY, HSQC, HMBC, INADEQUATE), and computational studies. The results demonstrate that the blue compound corresponds to 6'-hydroxy-4,4'-dimethoxy-1,1'-dimethyl-5'-{[3,4,5-trihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl] oxy}-[3,3'-bipyridine]-2,2',5,6(1H,1'H)-tetraone, a hermidin derivative, which we named chrozophoridin. Experimental data and computational modeling studies show that this mono-glycosylated dimer is represented by two stable isomers (atropisomers). This is an indispensable piece of knowledge for the characterization of this medieval dye in works of art such as medieval manuscript illuminations and for testing its stability and contributes to the preservation of our cultural heritage.
- 11th national meeting of organic chemistry and 4th meeting of therapeutic chemistryPublication . Sousa, Maria Emília; Araújo, Maria João; Do Vale, Maria Luísa; Andrade, Paula B.; Branco, Paula Cristina de Sério; Gomes, Paula; Moreira, Rui; Pinho E Melo, Teresa M.V.D.; Freitas, Victor; LAQV@REQUIMTE; DQ - Departamento de Química; CQFB-REQUIMTE - Centro de Química Fina e Biotecnologia (Lab. Associado REQUIMTE); Molecular Diversity Preservation International (MDPI)For the first time under the auspices of Sociedade Portuguesa de Química, the competences of two important fields of Chemistry are brought together into a single event, the 11st National Organic Chemistry Meeting and the the 4th National Medicinal Chemistry Meeting, to highlight complementarities and to promote new synergies. Abstracts of plenary lectures, oral communications, and posters presented during the meeting are collected in this report.