64 results on '"Simões, MF"'
Search Results
2. Pyrazinoic acid prodrugs active against mycobacteria
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Valente, E, Simões, MF, Anes, E, Testa, B, Constantino, L, and Repositório da Universidade de Lisboa
- Abstract
Made available in DSpace on 2015-12-30T10:18:50Z (GMT). No. of bitstreams: 0 Previous issue date: 2009
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- 2009
3. Plectrancthus Diterpenes Against Mycobacterium Tuberculosis
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Rijo, P, Simões, MF, Francisco, AP, Rojas, R, Gilman, RH, Vaisberg, AJ, Moiteiro, C, Rodríguez, B, and Repositório da Universidade de Lisboa
- Abstract
Made available in DSpace on 2015-12-30T10:18:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2008
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- 2008
4. Prodrugs of weak organic acids as antituberculous agents
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Constantino, L, Valente, E, Anes, E, Simões, MF, and Repositório da Universidade de Lisboa
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Made available in DSpace on 2015-12-30T10:18:50Z (GMT). No. of bitstreams: 0 Previous issue date: 2008
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- 2008
5. New pro-drugs against mycobacteria resistant to pyrazinamide
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Simões, MF, Valente, E, Constantino, L, Anes, E, and Repositório da Universidade de Lisboa
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Made available in DSpace on 2015-12-30T10:18:50Z (GMT). No. of bitstreams: 0 Previous issue date: 2007
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- 2007
6. Stability and Activity of Prodrugs with Potential anti-TB Activity
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Simões, MF, Valente, E, Constantino, L, Anes, E, and Repositório da Universidade de Lisboa
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Made available in DSpace on 2015-12-30T10:18:50Z (GMT). No. of bitstreams: 0 Previous issue date: 2007
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- 2007
7. Antimicrobial Activity of 7 alpha-acetoxy-6 beta-hidroxyroyleanone esters
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Rijo, P, Gameiro, AP, Simões, MF, Duarte, A, Rodriguez, B, and Repositório da Universidade de Lisboa
- Abstract
Made available in DSpace on 2015-12-30T10:18:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2006
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- 2006
8. Prediction of Antibacterial Activity of Diterpenes against MSRA with Machine Learning Methods
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Latino, DARS, Rijo, P, Pinheiro, L, Simões, MF, Freitas, FFM, Aires-de-Sousa, J, Calado, ART, Fernandes, FMSS, and Repositório da Universidade de Lisboa
- Abstract
Made available in DSpace on 2015-12-30T10:18:48Z (GMT). No. of bitstreams: 0 Previous issue date: 2006
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- 2006
9. Esters and Amide Prodrugs of Compounds With Anti-Tuberculosis Activity
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Simões, MF, Valente, E, Anes, E, Constantino, L, and Repositório da Universidade de Lisboa
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Made available in DSpace on 2015-12-30T10:18:50Z (GMT). No. of bitstreams: 0 Previous issue date: 2006
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- 2006
10. Abietane diterpenes from Plectranthus madagascariensis: A cytotoxicity screening
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Matias, D, primary, Pereira, F, additional, Nicolai, M, additional, Roberto, A, additional, Saraiva, N, additional, Fernandes, AS, additional, Simões, MF, additional, Lanza, AD, additional, Reis, CP, additional, and Rijo, P, additional
- Published
- 2014
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11. Antimicrobial screening of Plectranthus madagascariensis Benth. extracts
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Matias, D, primary, Pereira, F, additional, Pereira, M, additional, Simões, MF, additional, Diaz-Lanza, AM, additional, Reis, CP, additional, and Rijo, P, additional
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- 2014
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12. Royleanones Derivatives. Evaluation of the Antibacterial Activity
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Rijo, P, Marques, CG, Simões, MF, Araújo, ME, Duarte, A, and Repositório da Universidade de Lisboa
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Made available in DSpace on 2015-12-30T10:19:18Z (GMT). No. of bitstreams: 0 Previous issue date: 2003
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- 2003
13. Antioxidant Activity of Phenols from Plectranthus strigosus and P. fruticosus
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Marques, CG, Simões, MF, Rodríguez, B, and Repositório da Universidade de Lisboa
- Abstract
Made available in DSpace on 2015-12-30T10:19:18Z (GMT). No. of bitstreams: 0 Previous issue date: 2003
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- 2003
14. Antimicrobial activity of 7α-acetoxy-6β-hydroxyroyleanone 12-O-benzoyl esters
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Rijo, P, primary, Esteves, M, additional, Simões, MF, additional, Silva, A, additional, Duarte, A, additional, and Rodriguez, B, additional
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- 2008
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15. The burden of mental health issues in Behçet's disease: implications for patient quality of life.
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Teixeira CEG, Reis F, Dos Santos MPS, Simões MF, Del Rio APT, Coimbra IB, Pugliesi A, de Paiva Magalhães E, and Sachetto Z
- Abstract
Introduction: Depression and anxiety are among the most prevalent mental health conditions in Brazil. Both are associated with poor quality of life (HRQoL) and challenges in disease management for chronic illnesses, including Behçet's disease (BD). This study aimed to evaluate depression, anxiety, and HRQoL in BD patients from a non-endemic area., Research Design and Methods: This case-control study included adult BD patients from Brazilian tertiary center and healthy controls (HC). All patients fulfilled the ISG and ICBD diagnostic criteria. Depression, anxiety and quality of life were assessed using BDI, HADS, SF-36, and physical capacity with the HAQ., Results: We enrolled 58 BD patients (60% female, mean age 46.1) and 96 HC (74% female, mean age 44). High rates of depression and anxiety were observed in BD patients, correlating with disease activity, younger age, absence of a partner, shorter disease duration, and lower income. BD patients showed significant HRQoL restrictions, particularly in physical and emotional roles, compared to HC. Longer disease duration was correlated with better HRQoL., Conclusion: High rates of depression and anxiety were observed in BD patients, negatively impacting HRQoL, particularly in those with higher disease activity. Further study and clinical attention are warranted to enhance patient care and outcomes.
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- 2024
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16. A review of biomineralization in healing concrete: Mechanism, biodiversity, and application.
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Zhang J, Deng J, He Y, Wu J, Simões MF, Liu B, Li Y, Zhang S, and Antunes A
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- Construction Materials, Carbon, Biodiversity, Calcium Carbonate, Biomineralization
- Abstract
Concrete is the main ingredient in construction, but it inevitably fractures during its service life, requiring a large amount of cement and aggregate for maintenance. Concrete healing through biomineralization can repair cracks and improve the durability of concrete, which is conducive to saving raw materials and reducing carbon emissions. This paper reviews the biodiversity of microorganisms capable of precipitating mineralization to repair the concrete and their mineralization ability under different conditions. To better understand the mass transfer process of precipitates, two biomineralization mechanisms, microbially-controlled mineralization and microbially-induced mineralization, have been briefly described. The application of microorganisms in the field of healing concrete, comprising passive healing and intrinsic healing, is discussed. The key insight on the interaction between cementitious materials and microorganisms is the main approach for developing novel self-healing concrete in the future to improve the corrosion resistance of concrete. At the same time, the limitations and challenges are also pointed out., 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 Elsevier B.V. All rights reserved.)
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- 2024
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17. Effects of mycogenic silver nanoparticles on organisms of different trophic levels.
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Assis da Silva C, Ribeiro BM, Trotta CDV, Perina FC, Martins R, Moledo de Souza Abessa D, Barbieri E, Simões MF, and Ottoni CA
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- Ammonia, Animals, Anti-Bacterial Agents pharmacology, Antifungal Agents pharmacology, Daphnia, Silver toxicity, Silver Nitrate toxicity, Zebrafish, Chlorella vulgaris, Metal Nanoparticles toxicity
- Abstract
Biogenic silver nanoparticles (AgNPs) are considered a promising alternative to their synthetic versions. However, the environmental impact of such nanomaterials is still scarcely understood. Thus, the present study aims at assessing the antimicrobial action and ecotoxicity of AgNPs biosynthesized by the fungus Aspergillus niger IBCLP20 towards three freshwater organisms: Chlorella vulgaris, Daphnia similis, and Danio rerio (zebrafish). AgNPs IBCLP20 showed antibacterial action against Klebsiella pneumoniae between 5 and 100 μg mL
-1 , and antifungal action against Trichophyton mentagrophytes in concentrations ranging from 20 to 100 μg mL-1 . The cell density of the microalgae Chlorella vulgaris decreased 40% after 96 h of exposure to AgNPs IBCLP20, at the highest concentration analysed (100 μg L-1 ). The 48 h median lethal concentration for Daphnia similis was estimated as 4.06 μg L-1 (2.29-6.42 μg L-1 ). AgNPs IBCLP20 and silver nitrate (AgNO3 ) caused no acute toxicity on adult zebrafish, although they did induce several physiological changes. Mycosynthetized AgNPs caused a significant increase (p < 0.05) in oxygen consumption at the highest concentration studied (75 μg L-1 ) and an increase in the excretion of ammonia at the lower concentrations, followed by a reduction at the higher concentrations. Such findings are comparable with AgNO3 , which increased the oxygen consumption on low exposure concentrations, followed by a decrease at the high tested concentrations, while impairing the excretion of ammonia in all tested concentrations. The present results show that AgNPs IBCLP20 have biocidal properties. Mycogenic AgNPs induce adverse effects on organisms of different trophic levels and understanding their impact is detrimental to developing countermeasures aimed at preventing any negative environmental effects of such novel materials., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest., (Copyright © 2022 Elsevier Ltd. All rights reserved.)- Published
- 2022
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18. The archaeal class Halobacteria and astrobiology: Knowledge gaps and research opportunities.
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Wu JH, McGenity TJ, Rettberg P, Simões MF, Li WJ, and Antunes A
- Abstract
Water bodies on Mars and the icy moons of the outer solar system are now recognized as likely being associated with high levels of salt. Therefore, the study of high salinity environments and their inhabitants has become increasingly relevant for Astrobiology. Members of the archaeal class Halobacteria are the most successful microbial group living in hypersaline conditions and are recognized as key model organisms for exposure experiments. Despite this, data for the class is uneven across taxa and widely dispersed across the literature, which has made it difficult to properly assess the potential for species of Halobacteria to survive under the polyextreme conditions found beyond Earth. Here we provide an overview of published data on astrobiology-linked exposure experiments performed with members of the Halobacteria , identifying clear knowledge gaps and research opportunities., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Wu, McGenity, Rettberg, Simões, Li and Antunes.)
- Published
- 2022
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19. Habitability Models for Astrobiology.
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Méndez A, Rivera-Valentín EG, Schulze-Makuch D, Filiberto J, Ramírez RM, Wood TE, Dávila A, McKay C, Ceballos KNO, Jusino-Maldonado M, Torres-Santiago NJ, Nery G, Heller R, Byrne PK, Malaska MJ, Nathan E, Simões MF, Antunes A, Martínez-Frías J, Carone L, Izenberg NR, Atri D, Chitty HIC, Nowajewski-Barra P, Rivera-Hernández F, Brown CY, Lynch KL, Catling D, Zuluaga JI, Salazar JF, Chen H, González G, Jagadeesh MK, and Haqq-Misra J
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- Earth, Planet, Planets, Exobiology, Extraterrestrial Environment
- Abstract
Habitability has been generally defined as the capability of an environment to support life. Ecologists have been using Habitat Suitability Models (HSMs) for more than four decades to study the habitability of Earth from local to global scales. Astrobiologists have been proposing different habitability models for some time, with little integration and consistency among them, being different in function to those used by ecologists. Habitability models are not only used to determine whether environments are habitable, but they also are used to characterize what key factors are responsible for the gradual transition from low to high habitability states. Here we review and compare some of the different models used by ecologists and astrobiologists and suggest how they could be integrated into new habitability standards. Such standards will help improve the comparison and characterization of potentially habitable environments, prioritize target selections, and study correlations between habitability and biosignatures. Habitability models are the foundation of planetary habitability science, and the synergy between ecologists and astrobiologists is necessary to expand our understanding of the habitability of Earth, the Solar System, and extrasolar planets.
- Published
- 2021
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20. Hot-Melt Extrusion: a Roadmap for Product Development.
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Simões MF, Pinto RMA, and Simões S
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- Biological Availability, Drug Compounding methods, Drug Compounding trends, Hot Melt Extrusion Technology trends, Hot Temperature, Solubility, Technology, Pharmaceutical methods, Technology, Pharmaceutical trends, Thermodynamics, Chemistry, Pharmaceutical methods, Drug Carriers chemical synthesis, Drug Development methods, Hot Melt Extrusion Technology methods
- Abstract
Hot-melt extrusion has found extensive application as a feasible pharmaceutical technological option over recent years. HME applications include solubility enhancement, taste masking, and sustained drug release. As bioavailability enhancement is a hot topic of today's science, one of the main applications of HME is centered on amorphous solid dispersions. This review describes the most significant aspects of HME technology and its use to prepare solid dispersions as a drug formulation strategy to enhance the solubility of poorly soluble drugs. It also addresses molecular and thermodynamic features critical for the physicochemical properties of these systems, mainly in what concerns miscibility and physical stability. Moreover, the importance of applying the Quality by Design philosophy in drug development is also discussed, as well as process analytical technologies in pharmaceutical HME monitoring, under the current standards of product development and regulatory guidance. Graphical Abstract.
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- 2021
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21. Microbial Pathogenicity in Space.
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Simões MF and Antunes A
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After a less dynamic period, space exploration is now booming. There has been a sharp increase in the number of current missions and also of those being planned for the near future. Microorganisms will be an inevitable component of these missions, mostly because they hitchhike, either attached to space technology, like spaceships or spacesuits, to organic matter and even to us (human microbiome), or to other life forms we carry on our missions. Basically, we never travel alone. Therefore, we need to have a clear understanding of how dangerous our "travel buddies" can be; given that, during space missions, our access to medical assistance and medical drugs will be very limited. Do we explore space together with pathogenic microorganisms? Do our hitchhikers adapt to the space conditions, as well as we do? Do they become pathogenic during that adaptation process? The current review intends to better clarify these questions in order to facilitate future activities in space. More technological advances are needed to guarantee the success of all missions and assure the reduction of any possible health and environmental risks for the astronauts and for the locations being explored.
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- 2021
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22. Mycogenic Metal Nanoparticles for the Treatment of Mycobacterioses.
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Simões MF, Ottoni CA, and Antunes A
- Abstract
Mycobacterial infections are a resurgent and increasingly relevant problem. Within these, tuberculosis (TB) is particularly worrying as it is one of the top ten causes of death in the world and is the infectious disease that causes the highest number of deaths. A further concern is the on-going emergence of antimicrobial resistance, which seriously limits treatment. The COVID-19 pandemic has worsened current circumstances and future infections will be more incident. It is urgent to plan, draw solutions, and act to mitigate these issues, namely by exploring new approaches. The aims of this review are to showcase the extensive research and application of silver nanoparticles (AgNPs) and other metal nanoparticles (MNPs) as antimicrobial agents. We highlight the advantages of mycogenic synthesis, and report on their underexplored potential as agents in the fight against all mycobacterioses (non-tuberculous mycobacterial infections as well as TB). We propose further exploration of this field.
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- 2020
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23. Artificial neural networks applied to quality-by-design: From formulation development to clinical outcome.
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Simões MF, Silva G, Pinto AC, Fonseca M, Silva NE, Pinto RMA, and Simões S
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- Neural Networks, Computer, Particle Size, Quality Control, Solubility, Tablets chemistry, Therapeutic Equivalency, Chemistry, Pharmaceutical methods, Drug Compounding methods
- Abstract
Quality-by-Design (QbD) is a methodology used to build quality into products and is characterized by a well-defined roadmap. In this study, the application of Artificial Neural Networks (ANNs) in the QbD-based development of a test drug product is presented, where material specifications are defined and correlated with its performance in vivo. Along with other process parameters, drug particle size distribution (PSD) was identified as a critical material attribute and a three-tier specification was needed. An ANN was built with only five hidden nodes in one hidden layer, using hyperbolic tangent functions, and was validated using a random holdback of 33% of the dataset. The model led to significant and valid prediction formulas for the three responses, with R
2 values higher than 0.94 for all responses, both for the training and the validation datasets. The prediction formulas were applied to contour plots and tight limits were set based on the design space and feasible working area for the drug PSD, as well as for process parameters. The manufacturing process was validated through the production of three exhibit batches of 180,000 tablets in the industrial GMP facility, and the ANN model was applied to successfully predict the in vitro dissolution, with a bias of approximately 5%. The product was then tested on two clinical studies (under fasting and fed conditions) and the criteria to demonstrate bioequivalence to the Reference Listed Drug were met. In this study, ANNs were successfully applied to support the establishment of drug specifications and limits for process parameters, bridging the formulation development with in vitro performance and the positive clinical results obtained in the bioequivalence studies., Competing Interests: Declaration of Competing Interest The authors declared that there is no conflict of interest., (Copyright © 2020 Elsevier B.V. All rights reserved.)- Published
- 2020
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24. Enhanced solid-state stability of amorphous ibrutinib formulations prepared by hot-melt extrusion.
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Simões MF, Nogueira BA, Tabanez AM, Fausto R, Pinto RMA, and Simões S
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- Adenine chemistry, Crystallization, Hot Temperature, Polymers chemistry, Spectrum Analysis, Raman methods, Transition Temperature, Adenine analogs & derivatives, Drug Compounding methods, Drug Stability, Piperidines chemistry
- Abstract
One of the applications of Hot-Melt Extrusion (HME) is the stabilization of amorphous drugs through its incorporation into polymeric blends in the form of Amorphous Solid Dispersions (ASDs). In this study, HME was applied to solve a real problem in the development of an ibrutinib product, stabilizing the amorphous form. A systematic approach was followed by combining theoretical calculations, high-throughput screening (HTS) focused on physical stability and Principal Components Analysis (PCA). The HTS enabled the evaluation of 33 formulations for physical stability and the PCA was key to select four promising systems. The low relevance of drug loading on the drug crystallization supported the HME tests with a very high drug load of 50%. Milled extrudates were characterized and demonstrated to be fully amorphous. The thermal analysis detected a glass transition temperature much higher than the predicted values. Along with several weak intermolecular interactions detected in Raman spectroscopy, a dipolar interaction involving the α, β unsaturated ketone function of ibrutinib was also noticed. The additive effect of these intermolecular interactions changed markedly the performance of the ASDs. The physical strength of the prepared systems was corroborated by stability studies until 6 months at long-term and accelerated conditions., 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 © 2020 Elsevier B.V. All rights reserved.)
- Published
- 2020
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25. Biogenic Metal Nanoparticles: A New Approach to Detect Life on Mars?
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Simões MF, Ottoni CA, and Antunes A
- Abstract
Metal nanoparticles (MNPs) have been extensively studied. They can be produced via different methods (physical, chemical, or biogenic), but biogenic synthesis has become more relevant, mainly for being referred by many as eco-friendly and more advantageous than others. Biogenic MNPs have been largely used in a wide variety of applications, from industry, to agriculture, to health sectors, among others. Even though they are increasingly researched and used, there is still space for exploring further applications and increasing their functionality and our understanding of their synthesis process. Here, we provide an overview of MNPs and biogenic MNPs, and we analyze the potential application of their formation process to astrobiology and the detection of life on Mars and other worlds. According to current knowledge, we suggest that they can be used as potential biosignatures in extra-terrestrial samples. We present the advantages and disadvantages of this approach, suggest further research, and propose its potential use for the search for life in future space exploration.
- Published
- 2020
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26. Five-Stage Approach for a Systematic Screening and Development of Etravirine Amorphous Solid Dispersions by Hot-Melt Extrusion.
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Simões MF, Pereira A, Cardoso S, Cadonau S, Werner K, Pinto RMA, and Simões S
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- Biological Availability, Chemistry, Pharmaceutical methods, Drug Liberation, Drug Stability, Excipients chemistry, Microscopy, Polarization, Polyethylene Glycols chemistry, Polyvinyls chemistry, Povidone chemistry, Solubility, Spectrum Analysis, Raman, X-Ray Diffraction, Drug Carriers chemistry, Drug Compounding methods, Drug Evaluation, Preclinical methods, Hot Melt Extrusion Technology methods, Nitriles chemistry, Nitriles pharmacokinetics, Pyrimidines chemistry, Pyrimidines pharmacokinetics
- Abstract
The aim of this study was to develop a fast, effective, and material sparing screening method to design amorphous solid dispersions (ASDs) of etravirine to drive more effectively the development process, leading to improved bioavailability (BA) and stability. A systematic step-by-step approach was followed by combining theoretical calculations with high-throughput screening (HTS) and software-assisted multivariate statistical analysis. The thermodynamic miscibility and interaction of the drug in several polymers were predicted using Hansen solubility parameters (δ). The selected polymers were evaluated by HTS, using solvent evaporation. Binary compositions were evaluated by their solubilization capacity and physical stability over 2 months. JMP 14.0 was used for multivariate statistical analysis using principal components analysis. Extrusion was performed in Thermo Scientific HAAKE MiniLab II, and extrudates were characterized by assay, related substances, dissolution, and physical state (polarized light microscopy (PLM), Raman spectroscopy, and X-ray powder diffraction (XRPD)). A short stability study was performed where milled extrudates were exposed to 25 °C/60%RH and 40 °C/75%RH for 3 months. Through thermodynamic predictions, five main polymers were selected. The HTS enabled the evaluation of 42 formulations for solubilization capacity and physical stability. The three most promising compositions were selected for hot-melt extrusion (HME) tests. In general, a good correlation was found among the results of theoretical predictions, HTS, and HME. Poly(vinylpyrrolidone) (PVP)-based formulations were shown to be easily extrudable, with low degradation and complete amorphicity, whereas in Soluplus, the drug was not miscible, leading to a high crystalline content. The drug release rate was improved more than two times with PVP, and the manufactured ASD was demonstrated to be stable physically and chemically. A fast and effective screening technique to develop stable ASDs for a poorly soluble drug was successfully developed as applied to etravirine. The given method is easy to use, requires a low amount of drug, and is fairly accurate in predicting the amorphization of the drug when formulated. The success of HME formulation development of etravirine was undoubtedly enhanced with this high-throughput tool, which led to the identification of extrudates with improved biopharmaceutical properties. The structural characterization performed by PLM, XRPD, and Raman spectroscopy demonstrated that the HME prototype was essentially amorphous. The unexpected stability at 40 °C/75%RH was correlated with the presence of molecular interaction characterized by Raman spectroscopy.
- Published
- 2020
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27. Earth's Stratosphere and Microbial Life.
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DasSarma P, Antunes A, Simões MF, and DasSarma S
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- Atmospheric Pressure, Bacteria growth & development, Bacteria radiation effects, Cold-Shock Response, Cosmic Radiation, Desiccation, Dust, Exobiology, Nutrients, Ultraviolet Rays, Atmosphere, Bacteria isolation & purification, Earth, Planet, Extreme Environments
- Abstract
The Earth's atmosphere is an extremely large and sparse environment which is quite challenging for the survival of microorganisms. We have long wondered about the limits to life in the atmosphere, starting with Leeuwenhoek's observation of "animalcules" collected from the air. In the past century, significant progress has been made to capture and identify biological material from varying elevations, from a few meters above ground level, to the clouds near mountaintops, and the jet streams, the ozone layer, and even higher up in the stratosphere. Collection and detection techniques have been developed and advanced in order to assess the potential diversity of life from very high altitudes. Studies of microbial life in the stratosphere with its multiple stressors (cold, dry, irradiated, with low pressure and limited nutrients), have recently garnered considerable attention. Here, we review studies of Earth's atmosphere, with emphasis on the stratosphere, addressing implications for astrobiology, the dispersal of microbes around our planet, planetary protection, and climate change.
- Published
- 2020
- Full Text
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28. Hot-melt extrusion in the pharmaceutical industry: toward filing a new drug application.
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Simões MF, Pinto RMA, and Simões S
- Subjects
- Chemistry, Pharmaceutical, Drug Carriers, Drug Compounding, Drug Industry, Humans, Polymers, Hot Melt Extrusion Technology trends, Pharmaceutical Preparations chemistry, Technology, Pharmaceutical methods
- Abstract
The pharmaceutical development of amorphous solid dispersions (ASDs) by hot-melt extrusion (HME) is briefly reviewed. A systematic step-by-step approach is presented, where thermodynamics, polymer screening, multivariate statistics and process optimization are combined, to increase the success of HME-based drug product development. The quality by design (QbD) concept is introduced and applied to HME. Steps and tools for its effective implementation are provided, including risk assessment highlighting crucial points. The technical and scientific specificities of HME-based ASDs are discussed in light of the current paradigm of drug development and in-line with regulatory guidelines from the ICH regions. Case studies of recently approved HME products are presented., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)
- Published
- 2019
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29. Polyphasic, Including MALDI-TOF MS, Evaluation of Freeze-Drying Long-Term Preservation on Aspergillus (Section Nigri ) Strains.
- Author
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Rodriguez R, Santos C, Simões MF, Soares C, Santos C, and Lima N
- Abstract
This study aims to evaluate the effect of freeze-drying and long-term storage on the biotechnological potential of Aspergillus section Nigri strains. Twelve selected strains were freeze-dried and aged by accelerated storage, at 37 °C in the dark, for 2 and 4 weeks. To assess possible changes as a consequence of the ageing in the freeze-drying ampoules, morphological characteristics, mycotoxins and enzymes production, matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALTI-TOF MS) spectra, and M13 phage probe fingerprinting were used as part of a polyphasic approach. Phenotypical changes were observed; nevertheless, they did not substantially affect the potential biotechnological use of these strains. The activity of hydrolytic enzymes (protease, carboxymethylcellulase, xylanase, pectinase and mannanase) was maintained or increased after freeze-drying. MALDI-TOF MS data originated spectra that grouped, for the majority of samples, according to strain independently of preservation time point. M13 profiles revealed the presence of some genetic polymorphisms after preservation. However, the three studied times still clustered for more than 50% of strains. Our results show that the studied strains maintain their biotechnological potential after preservation, with minimal phenotypic alterations. These findings provide evidence that freeze-drying preservation is a suitable option to preserve biotechnologically relevant aspergilli strains from section Nigri , and one should consider that the observed effects might be species/strain-dependent.
- Published
- 2019
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30. Application of microbial fuel cell technology for vinasse treatment and bioelectricity generation.
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Ottoni CA, Simões MF, Santos JG, Peixoto L, Martins CR, Silva BP, Neto AO, Brito AG, and Maiorano AE
- Subjects
- Bioelectric Energy Sources, Saccharum chemistry
- Abstract
Objective: Our study evaluated the performance of different two-chambered microbial fuel cell (MFC) prototypes, operated with variable distance between electrodes and Nafion membrane and specific inoculum concentration, applied for vinasse treatment., Results: The performance of the developed MFC resulted in a maximum current density of 1200 mA m
-2 and power density of 800 mW m-2 in a period of 61 days. MFC performed a chemical oxygen demand removal at a rate ranging from 51 to 60%., Conclusions: Taking our preliminary results into consideration, we concluded that the MFC technology presents itself as highly promising for the treatment of vinasse.- Published
- 2019
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31. Stage III Non-Small-Cell Lung Cancer Treated With Concurrent Chemoradiation Followed or Not by Consolidation Chemotherapy: A Survival Analysis From a Brazilian Multicentric Cohort.
- Author
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Cordeiro de Lima VC, Baldotto CS, Barrios CH, Sobrinho EM, Zukin M, Mathias C, Zaffaroni F, Nery RC, Madeira G, Amadio AV, Coelho JC, Geib G, Simões MF, and Castro G Jr
- Subjects
- Aged, Brazil epidemiology, Carboplatin administration & dosage, Carcinoma, Non-Small-Cell Lung pathology, Cisplatin administration & dosage, Combined Modality Therapy, Consolidation Chemotherapy, Female, Humans, Kaplan-Meier Estimate, Male, Middle Aged, Paclitaxel administration & dosage, Progression-Free Survival, Treatment Outcome, Antineoplastic Combined Chemotherapy Protocols administration & dosage, Carcinoma, Non-Small-Cell Lung drug therapy, Carcinoma, Non-Small-Cell Lung radiotherapy, Chemoradiotherapy
- Abstract
Purpose: Of newly diagnosed patients with non-small-cell lung cancer (NSCLC), stage III accounts for 30%. Most patients are treated with concurrent chemoradiation therapy, but the addition of consolidation chemotherapy (CC) is debatable. We examined the effect of CC in Brazilian patients with stage III NSCLC treated in routine clinical practice., Methods: We retrospectively collected data for patients from five different Brazilian cancer institutions who had stage III NSCLC and who were treated with chemoradiation therapy followed or not by CC. Eligible patients were age 18 years or older and must have been treated with cisplatin-carboplatin plus etoposide, paclitaxel, or vinorelbine, concurrently with thoracic radiation therapy (RT). Patients treated with surgery or neoadjuvant chemotherapy were excluded. The primary end point was overall survival (OS). Associations between CC and clinical variables and demographics were evaluated by using Pearson's χ
2 test. Survival curves were calculated by using the Kaplan-Meier method and were compared using the log-rank test. Univariable and multivariable analysis used a Cox proportional hazards model., Results: We collected data from 165 patients. Median age was 60 years. Most patients were male (69.1%), white (77.9%), current or former smokers (93.3%), and had stage IIIB disease (52.7%). Adenocarcinoma was the most common histology (47.9%). Weight loss of more than 5% was observed in 39.1% and Eastern Cooperative Oncology Group performance status of 2 was observed in 14.6%. The only variable associated with CC was T stage ( P = .022). We observed no statistically significant difference in OS between patients treated or not with CC ( P = .128). A total delivered RT dose ≥ 61 Gy was the only variable independently associated with improved survival ( P = .012)., Conclusion: Brazilian patients with locally advanced NSCLC who were treated with standard treatment achieved OS similar to that reported in randomized trials. CC did not improve OS in patients with stage III NSCLC after concurrent chemoradiation therapy. An RT dose of less than 61 Gy had a negative effect on OS.- Published
- 2018
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32. Discovery of a small-molecule protein kinase Cδ-selective activator with promising application in colon cancer therapy.
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Bessa C, Soares J, Raimundo L, Loureiro JB, Gomes C, Reis F, Soares ML, Santos D, Dureja C, Chaudhuri SR, Lopez-Haber C, Kazanietz MG, Gonçalves J, Simões MF, Rijo P, and Saraiva L
- Subjects
- Colonic Neoplasms pathology, Humans, Protein Kinase C-delta pharmacology, Colonic Neoplasms therapy, Protein Kinase C-delta therapeutic use
- Abstract
Protein kinase C (PKC) isozymes play major roles in human diseases, including cancer. Yet, the poor understanding of isozymes-specific functions and the limited availability of selective pharmacological modulators of PKC isozymes have limited the clinical translation of PKC-targeting agents. Here, we report the first small-molecule PKCδ-selective activator, the 7α-acetoxy-6β-benzoyloxy-12-O-benzoylroyleanone (Roy-Bz), which binds to the PKCδ-C1-domain. Roy-Bz potently inhibited the proliferation of colon cancer cells by inducing a PKCδ-dependent mitochondrial apoptotic pathway involving caspase-3 activation. In HCT116 colon cancer cells, Roy-Bz specifically triggered the translocation of PKCδ but not other phorbol ester responsive PKCs. Roy-Bz caused a marked inhibition in migration of HCT116 cells in a PKCδ-dependent manner. Additionally, the impairment of colonosphere growth and formation, associated with depletion of stemness markers, indicate that Roy-Bz also targets drug-resistant cancer stem cells, preventing tumor dissemination and recurrence. Notably, in xenograft mouse models, Roy-Bz showed a PKCδ-dependent antitumor effect, through anti-proliferative, pro-apoptotic, and anti-angiogenic activities. Besides, Roy-Bz was non-genotoxic, and in vivo it had no apparent toxic side effects. Collectively, our findings reveal a novel promising anticancer drug candidate. Most importantly, Roy-Bz opens the way to a new era on PKC biology and pharmacology, contributing to the potential redefinition of the structural requirements of isozyme-selective agents, and to the re-establishment of PKC isozymes as feasible therapeutic targets in human diseases.
- Published
- 2018
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33. Screening of filamentous fungi for antimicrobial silver nanoparticles synthesis.
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Ottoni CA, Simões MF, Fernandes S, Dos Santos JG, da Silva ES, de Souza RFB, and Maiorano AE
- Abstract
The present work had the goal of screening a batch of 20 fungal strains, isolated from sugar cane plantation soil, in order to identify those capable of biosynthesis of silver nanoparticles. These nanoparticles are known to have a large and effective application in clinical microbiology. Four strains were found to be capable of biosynthesis of silver nanoparticles. The biosynthesised nanoparticles were characterised by UV-vis spectroscopy, scanning electron microscopy, EDX, and XRD. They were found to have an average size of 30-100 nm, a regular round shape, and potential antimicrobial activity against Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa. The antimicrobial activity was found to be directly related to the nanoparticles concentration. Mycogenic synthesis of nanoparticles is a green biogenic process preferable to other alternatives. Because fungi are great producers of extracellular enzymes this process makes scaling-up an easier task with high importance for clinical microbiology on the fight against microbial resistance, as well as for other industrial applications.
- Published
- 2017
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34. Antiparasitic Activity of Diterpenoids Against Trypanosoma cruzi.
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Alegre-Gómez S, Sainz P, Simões MF, Rijo P, Moiteiro C, González-Coloma A, and Martínez-Díaz RA
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- Animals, Antiparasitic Agents chemistry, Cell Line, Diterpenes chemistry, Humans, Inhibitory Concentration 50, Mice, Plant Extracts chemistry, Plant Extracts pharmacology, Plectranthus chemistry, Antiparasitic Agents pharmacology, Diterpenes pharmacology, Trypanosoma cruzi drug effects
- Abstract
Twenty-seven diterpenes, including abietanes, labdanes, abeoabietanes, halimanes, and pimaranes, have been evaluated against epimastigote and intracellular amastigote forms of Trypanosoma cruzi and also against LC5 and NCTC cell lines. Royleanones ( 3, 4 , and 5 ) and a further abietane ( 12 ), obtained by purification of Plectranthus spp. extracts, were the most active compounds on epimastigotes, showing IC
50 values similar (1.73 µg/mL, 12 ) or even lower (0.39, 0.99, and 1.20 µg/mL, 3, 4 , and 5 respectively) than the positive control nifurtimox (2.3 µg/mL). On intracellular amastigotes, abietanes 3, 4 , and 5 showed a significant activity with IC50 values of 0.83, < 0.31, and 0.62 µg/mL, respectively, but were less potent than the positive control nifurtimox (IC50 < 0.16 µg/mL). Compounds 3, 4 , and 5 were not cytotoxic to LC5 and NCTC 929 cells at 1 µg/mL., (Georg Thieme Verlag KG Stuttgart · New York.)- Published
- 2017
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35. Bioprospecting Red Sea Coastal Ecosystems for Culturable Microorganisms and Their Antimicrobial Potential.
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Al-Amoudi S, Essack M, Simões MF, Bougouffa S, Soloviev I, Archer JA, Lafi FF, and Bajic VB
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- Bacteria classification, Bacteria drug effects, Bacteria genetics, Bacteria isolation & purification, Geologic Sediments microbiology, Indian Ocean, Microbial Sensitivity Tests, Phylogeny, Polymerase Chain Reaction, RNA, Ribosomal, 16S biosynthesis, RNA, Ribosomal, 16S genetics, Rhizophoraceae microbiology, Soil Microbiology, Anti-Infective Agents pharmacology, Biological Products pharmacology, Ecosystem, Water Microbiology
- Abstract
Microorganisms that inhabit unchartered unique soil such as in the highly saline and hot Red Sea lagoons on the Saudi Arabian coastline, represent untapped sources of potentially new bioactive compounds. In this study, a culture-dependent approach was applied to three types of sediments: mangrove mud (MN), microbial mat (MM), and barren soil (BS), collected from Rabigh harbor lagoon (RHL) and Al-Kharrar lagoon (AKL). The isolated bacteria were evaluated for their potential to produce bioactive compounds. The phylogenetic characterization of 251 bacterial isolates based on the 16S rRNA gene sequencing, supported their assignment to five different phyla: Proteobacteria, Firmicutes, Actinobacteria, Bacteroidetes, and Planctomycetes. Fifteen putative novel species were identified based on a 16S rRNA gene sequence similarity to other strain sequences in the NCBI database, being ≤98%. We demonstrate that 49 of the 251 isolates exhibit the potential to produce antimicrobial compounds. Additionally, at least one type of biosynthetic gene sequence, responsible for the synthesis of secondary metabolites, was recovered from 25 of the 49 isolates. Moreover, 10 of the isolates had a growth inhibition effect towards Staphylococcus aureus, Salmonella typhimurium and Pseudomonas syringae. We report the previously unknown antimicrobial activity of B. borstelensis, P. dendritiformis and M. salipaludis against all three indicator pathogens. Our study demonstrates the evidence of diverse cultured microbes associated with the Red Sea harbor/lagoon environments and their potential to produce antimicrobial compounds., Competing Interests: The authors declare no conflict of interest.
- Published
- 2016
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36. High Laccase Expression by Trametes versicolor in a Simulated Textile Effluent with Different Carbon Sources and PHs.
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Ottoni C, Simões MF, Fernandes S, Santos CR, and Lima N
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- Alkalies metabolism, Biodegradation, Environmental, Color, Laccase genetics, Naphthalenesulfonates, Polymerase Chain Reaction, Portugal, Trametes genetics, Water Pollutants, Chemical, Bioreactors, Carbon metabolism, Coloring Agents metabolism, Hydrogen-Ion Concentration, Laccase biosynthesis, Textile Industry, Trametes metabolism
- Abstract
Textile effluents are highly polluting and have variable and complex compositions. They can be extremely complex, with high salt concentrations and alkaline pHs. A fixed-bed bioreactor was used in the present study to simulate a textile effluent treatment, where the white-rot fungus, Trametes versicolor, efficiently decolourised the azo dye Reactive Black 5 over 28 days. This occurred under high alkaline conditions, which is unusual, but advantageous, for successful decolourisation processes. Active dye decolourisation was maintained by operation in continuous culture. Colour was eliminated during the course of operation and maximum laccase (Lcc) activity (80.2 U∙L(-1)) was detected after glycerol addition to the bioreactor. Lcc2 gene expression was evaluated with different carbon sources and pH values based on reverse transcriptase-PCR (polymerase chain reaction). Glycerol was shown to promote the highest lcc2 expression at pH 5.5, followed by sucrose and then glucose. The highest levels of expression occurred between three and four days, which corroborate the maximum Lcc activity observed for sucrose and glycerol on the bioreactor. These results give new insights into the use of T. versicolor in textile dye wastewater treatment with high pHs.
- Published
- 2016
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37. Establishment of a Quality Management System Based on ISO 9001 Standard in a Public Service Fungal Culture Collection.
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Simões MF, Dias N, Santos C, and Lima N
- Abstract
Collaborations between different Microbiological Resource Centres (mBRCs) and ethical sourcing practices are mandatory to guarantee biodiversity conservation, successful and sustainable preservation and fair share of benefits that arise from the use of genetic resources. Since microbial Culture Collections (CCs) are now engaged in meeting high quality operational standards, they are facing the challenge of establishing quality control criteria to certify their biological materials. The authentication/certification of strains is nowadays a demand from the bioeconomy sector for the global operation of mBRCs. The achievement of consistent quality assurance and trust within the mBRCs and microbial CCs context is a dynamic and never-ending process. A good option to facilitate that process is to implement a Quality Management System (QMS) based on the ISO 9001 standard. Here, we report a detailed description of all the steps taken for the QMS implementation at the Portuguese CC of filamentous fungi: Micoteca da Universidade do Minho (MUM). Our aim is to provide guidelines for the certification of other CCs, so that they can also enhance the search and choice of the most consistent, reliable, and effective operating methods, with assured procedures and validation of preservation; and guarantee trustworthy relations with all stakeholders., Competing Interests: The authors declare no conflict of interest.
- Published
- 2016
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38. Rhizosphere microbiome metagenomics of gray mangroves (Avicennia marina) in the Red Sea.
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Alzubaidy H, Essack M, Malas TB, Bokhari A, Motwalli O, Kamanu FK, Jamhor SA, Mokhtar NA, Antunes A, Simões MF, Alam I, Bougouffa S, Lafi FF, Bajic VB, and Archer JA
- Subjects
- Avicennia genetics, Avicennia metabolism, Indian Ocean, Saudi Arabia, Avicennia microbiology, Metagenomics, Microbiota, Rhizosphere
- Abstract
Mangroves are unique, and endangered, coastal ecosystems that play a vital role in the tropical and subtropical environments. A comprehensive description of the microbial communities in these ecosystems is currently lacking, and additional studies are required to have a complete understanding of the functioning and resilience of mangroves worldwide. In this work, we carried out a metagenomic study by comparing the microbial community of mangrove sediment with the rhizosphere microbiome of Avicennia marina, in northern Red Sea mangroves, along the coast of Saudi Arabia. Our results revealed that rhizosphere samples presented similar profiles at the taxonomic and functional levels and differentiated from the microbiome of bulk soil controls. Overall, samples showed predominance by Proteobacteria, Bacteroidetes and Firmicutes, with high abundance of sulfate reducers and methanogens, although specific groups were selectively enriched in the rhizosphere. Functional analysis showed significant enrichment in 'metabolism of aromatic compounds', 'mobile genetic elements', 'potassium metabolism' and 'pathways that utilize osmolytes' in the rhizosphere microbiomes. To our knowledge, this is the first metagenomic study on the microbiome of mangroves in the Red Sea, and the first application of unbiased 454-pyrosequencing to study the rhizosphere microbiome associated with A. marina. Our results provide the first insights into the range of functions and microbial diversity in the rhizosphere and soil sediments of gray mangrove (A. marina) in the Red Sea., (Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2016
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39. Esters of Pyrazinoic Acid Are Active against Pyrazinamide-Resistant Strains of Mycobacterium tuberculosis and Other Naturally Resistant Mycobacteria In Vitro and Ex Vivo within Macrophages.
- Author
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Pires D, Valente E, Simões MF, Carmo N, Testa B, Constantino L, and Anes E
- Subjects
- Alcohols pharmacology, Cell Line, Cell Survival drug effects, Drug Resistance, Bacterial, Esters, Humans, Microbial Sensitivity Tests, Moraxella bovis drug effects, Mycobacterium avium Complex drug effects, Prodrugs, Pyrazinamide chemical synthesis, Antitubercular Agents pharmacology, Macrophages microbiology, Mycobacterium drug effects, Mycobacterium tuberculosis drug effects, Pyrazinamide analogs & derivatives, Pyrazinamide pharmacology
- Abstract
Pyrazinamide (PZA) is active against major Mycobacterium tuberculosis species (M. tuberculosis, M. africanum, and M. microti) but not against M. bovis and M. avium. The latter two are mycobacterial species involved in human and cattle tuberculosis and in HIV coinfections, respectively. PZA is a first-line agent for the treatment of human tuberculosis and requires activation by a mycobacterial pyrazinamidase to form the active metabolite pyrazinoic acid (POA). As a result of this mechanism, resistance to PZA, as is often found in tuberculosis patients, is caused by point mutations in pyrazinamidase. In previous work, we have shown that POA esters and amides synthesized in our laboratory were stable in plasma (M. F. Simões, E. Valente, M. J. Gómez, E. Anes, and L. Constantino, Eur J Pharm Sci 37:257-263, 2009, http://dx.doi.org/10.1016/j.ejps.2009.02.012). Although the amides did not present significant activity, the esters were active against sensitive mycobacteria at concentrations 5- to 10-fold lower than those of PZA. Here, we report that these POA derivatives possess antibacterial efficacy in vitro and ex vivo against several species and strains of Mycobacterium with natural or acquired resistance to PZA, including M. bovis and M. avium. Our results indicate that the resistance probably was overcome by cleavage of the prodrugs into POA and a long-chain alcohol. Although it is not possible to rule out that the esters have intrinsic activity per se, we bring evidence here that long-chain fatty alcohols possess a significant antimycobacterial effect against PZA-resistant species and strains and are not mere inactive promoieties. These findings may lead to candidate dual drugs having enhanced activity against both PZA-susceptible and PZA-resistant isolates and being suitable for clinical development., (Copyright © 2015, American Society for Microbiology. All Rights Reserved.)
- Published
- 2015
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40. The abietane diterpenoid parvifloron D from Plectranthus ecklonii is a potent apoptotic inducer in human leukemia cells.
- Author
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Burmistrova O, Perdomo J, Simões MF, Rijo P, Quintana J, and Estévez F
- Subjects
- Antineoplastic Agents, Phytogenic pharmacology, Caspases metabolism, HL-60 Cells drug effects, Humans, K562 Cells drug effects, Leukocytes, Mononuclear drug effects, Membrane Potential, Mitochondrial drug effects, Molecular Structure, Reactive Oxygen Species metabolism, Abietanes pharmacology, Apoptosis drug effects, Plectranthus chemistry
- Abstract
Background: Abietane diterpenes have attracted much attention because they display a wide range of biological activities, including antitumor activities. These compounds are the most diverse of the diterpenoids isolated from species of Plectranthus. Naturally occurring diterpene parvifloron D is the main phytochemical constituent of Plectranthus ecklonii. To examine the therapeutic potential of the plant, we evaluated whether parvifloron D displays cytotoxicity against human tumor cells., Methods: The cytotoxicity was analyzed by colorimetric 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay. Apoptosis was evaluated by fluorescent microscopy, transmission electron microscopy, flow cytometric analysis of annexin V-FITC and propidium iodide-stained cells and DNA fragmentation. Protein expression and processing and release of mitochondrial proteins were analyzed by Western blot. Caspase activity was determined using colorimetric substrates. The membrane potential and intracellular reactive oxygen species were detected by flow cytometry., Results: Parvifloron D displays strong cytotoxic properties against leukemia cells (HL-60, U-937, MOLT-3 and K-562) and in particular P-glycoprotein-overexpressing K-562/ADR cells, but has only weak cytotoxic effects on peripheral blood mononuclear cells (PBMCs). Overexpression of the protective mitochondrial proteins Bcl-2 and Bcl-xL did not confer resistance to parvifloron D-induced cytotoxicity. Growth inhibition of HL-60 cells that was triggered by parvifloron D was found to be caused by a rapid induction of apoptotic cell death. This apoptosis was prevented by the non-specific caspase inhibitor z-VAD-fmk, and by the selective caspase-9 inhibitor z-LEHD-fmk. Cell death induced by parvifloron D was found to be (i) associated with the dissipation of the mitochondrial membrane potential and the release of cytochrome c, (ii) amplified by inhibition of extracellular signal-regulated kinases (ERKs) 1/2 signaling and (iii) caused by a mechanism dependent on intracellular reactive oxygen species generation., Conclusion: Parvifloron D is a potent cytotoxic compound against several human tumor cells and also a fast and potent apoptotic inducer in leukemia cells., (Copyright © 2015 Elsevier GmbH. All rights reserved.)
- Published
- 2015
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41. First Insights into the Viral Communities of the Deep-sea Anoxic Brines of the Red Sea.
- Author
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Antunes A, Alam I, Simões MF, Daniels C, Ferreira AJ, Siam R, El-Dorry H, and Bajic VB
- Subjects
- Archaea genetics, Archaea virology, Bacteria genetics, Bacteria virology, Caudovirales genetics, Indian Ocean, Metagenomics methods, Phycodnaviridae genetics, Plant Viruses genetics, Salts, Caudovirales isolation & purification, Phycodnaviridae isolation & purification, Plant Viruses isolation & purification, Seawater virology
- Abstract
The deep-sea brines of the Red Sea include some of the most extreme and unique environments on Earth. They combine high salinities with increases in temperature, heavy metals, hydrostatic pressure, and anoxic conditions, creating unique settings for thriving populations of novel extremophiles. Despite a recent increase of studies focusing on these unusual biotopes, their viral communities remain unexplored. The current survey explores four metagenomic datasets obtained from different brine-seawater interface samples, focusing specifically on the diversity of their viral communities. Data analysis confirmed that the particle-attached viral communities present in the brine-seawater interfaces were diverse and generally dominated by Caudovirales, yet appearing distinct from sample to sample. With a level of caution, we report the unexpected finding of Phycodnaviridae, which infects algae and plants, and trace amounts of insect-infecting Iridoviridae. Results from Kebrit Deep revealed stratification in the viral communities present in the interface: the upper-interface was enriched with viruses associated with typical marine bacteria, while the lower-interface was enriched with haloviruses and halophages. These results provide first insights into the unexplored viral communities present in deep-sea brines of the Red Sea, representing one of the first steps for ongoing and future sampling efforts and studies., (Copyright © 2015 The Authors. Production and hosting by Elsevier Ltd.. All rights reserved.)
- Published
- 2015
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42. Soil and Rhizosphere Associated Fungi in Gray Mangroves (Avicennia marina) from the Red Sea--A Metagenomic Approach.
- Author
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Simões MF, Antunes A, Ottoni CA, Amini MS, Alam I, Alzubaidy H, Mokhtar NA, Archer JA, and Bajic VB
- Subjects
- Ascomycota isolation & purification, Basidiomycota isolation & purification, Biodiversity, Ecosystem, Indian Ocean, Metagenomics, Soil, Soil Microbiology, Ascomycota genetics, Avicennia microbiology, Basidiomycota genetics, Plant Roots microbiology, Rhizosphere
- Abstract
Covering a quarter of the world's tropical coastlines and being one of the most threatened ecosystems, mangroves are among the major sources of terrestrial organic matter to oceans and harbor a wide microbial diversity. In order to protect, restore, and better understand these ecosystems, researchers have extensively studied their microbiology, yet few surveys have focused on their fungal communities. Our lack of knowledge is even more pronounced for specific fungal populations, such as the ones associated with the rhizosphere. Likewise, the Red Sea gray mangroves (Avicennia marina) remain poorly characterized, and understanding of their fungal communities still relies on cultivation-dependent methods. In this study, we analyzed metagenomic datasets from gray mangrove rhizosphere and bulk soil samples collected in the Red Sea coast, to obtain a snapshot of their fungal communities. Our data indicated that Ascomycota was the dominant phylum (76%-85%), while Basidiomycota was less abundant (14%-24%), yet present in higher numbers than usually reported for such environments. Fungal communities were more stable within the rhizosphere than within the bulk soil, both at class and genus level. This finding is consistent with the intrinsic patchiness in soil sediments and with the selection of specific microbial communities by plant roots. Our study indicates the presence of several species on this mycobiome that were not previously reported as mangrove-associated. In particular, we detected representatives of several commercially-used fungi, e.g., producers of secreted cellulases and anaerobic producers of cellulosomes. These results represent additional insights into the fungal community of the gray mangroves of the Red Sea, and show that they are significantly richer than previously reported., (Copyright © 2015 The Authors. Production and hosting by Elsevier Ltd.. All rights reserved.)
- Published
- 2015
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43. In vitro antimicrobial activity of royleanone derivatives against Gram-positive bacterial pathogens.
- Author
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Rijo P, Duarte A, Francisco AP, Semedo-Lemsaddek T, and Simões MF
- Subjects
- Abietanes chemistry, Abietanes isolation & purification, Animals, Anti-Bacterial Agents chemistry, Anti-Bacterial Agents isolation & purification, Chlorocebus aethiops, Microbial Sensitivity Tests, Molecular Structure, Vero Cells, Abietanes pharmacology, Anti-Bacterial Agents pharmacology, Enterococcus drug effects, Plant Extracts pharmacology, Plectranthus chemistry, Staphylococcus aureus drug effects
- Abstract
Infections caused by multiresistant bacterial pathogens are a significant problem worldwide, turning the search for natural compounds to act as alternatives to antibiotics of major importance. The aim of the present study was to investigate the in vitro antimicrobial activity of 7α-acetoxy-6β-hydroxyroyleanone (1), isolated from Plectranthus grandidentatus (Lamiaceae), and 11 additional royleanone abietane derivatives of 1 (2-12) against important Gram-positive human bacterial pathogens. Results showed that the aromatic and alkylic esters 2, 3 and 5 are more active than 1 against Enterococcus and Staphylococcus (minimum inhibitory concentration (MIC) values ranging from 0.98 to 62.50 µg/mL). Moreover, 7α-acetoxy-6β-hydroxy-12-O-(4-chloro)benzoylroyleanone (2) gave rise to a new antibacterial-prototype (MIC values of 3.91-15.63 µg/mL against Staphylococcus and of 0.98-3.91 µg/mL against Enterococcus). The results showed that the compounds under analysis also present antimicrobial activity against resistant bacteria. The hydrophobic extra-interactions with bacterial targets seem to play an important role on the activity of royleanones derivatives., (Copyright © 2013 John Wiley & Sons, Ltd.)
- Published
- 2014
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44. Structural diversity of Aspergillus (section nigri) spores.
- Author
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Simões MF, Santos C, and Lima N
- Subjects
- Aspergillus classification, Mass Spectrometry, Microscopy, Electron, Scanning, Spores, Fungal classification, Aspergillus chemistry, Aspergillus cytology, Spores, Fungal chemistry, Spores, Fungal cytology
- Abstract
The taxonomy of fungal species, similar to that of many other microorganisms, suffers frequent revisions due to the discovery of new species and to the development and gathering of characterization data and morphological information. Morpho-taxonomy helps in the identification of many species. This work presents the macro, micro-morphological, and spectral mass analyses for phenotypic characterization of 13 species of Aspergillus section Nigri, showing that the characterization of spores (conidia) by scanning electron microscopy can be used as a tool to discriminate key morphological characteristics and separate closely related fungi. These results were corroborated by colony plates, stereomicroscopy, light microscopy, and spectral mass data.
- Published
- 2013
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45. Antiproliferative activity of abietane diterpenoids against human tumor cells.
- Author
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Burmistrova O, Simões MF, Rijo P, Quintana J, Bermejo J, and Estévez F
- Subjects
- Abietanes chemistry, Amino Acid Chloromethyl Ketones pharmacology, Antineoplastic Agents, Phytogenic chemistry, Apoptosis drug effects, Apoptosis Inducing Factor metabolism, Caspase 8 metabolism, Cytochromes c metabolism, Diterpenes chemistry, Drug Screening Assays, Antitumor, Extracellular Signal-Regulated MAP Kinases metabolism, HL-60 Cells, Humans, JNK Mitogen-Activated Protein Kinases metabolism, Membrane Potential, Mitochondrial, Mitochondria metabolism, Mitogen-Activated Protein Kinases metabolism, Oligopeptides pharmacology, Proto-Oncogene Proteins c-bcl-2 metabolism, Signal Transduction, bcl-2-Associated X Protein metabolism, bcl-X Protein metabolism, p38 Mitogen-Activated Protein Kinases metabolism, Abietanes pharmacology, Antineoplastic Agents, Phytogenic pharmacology, Diterpenes pharmacology
- Abstract
In the present study, the cytotoxicity of 30 diterpenoids with an abietane or a halimane skeleton was determined against five human tumor cell lines (HL-60, U937, Molt-3, SK-MEL-1, and MCF-7). Diterpenoids containing an abietane skeleton including taxodone (1) and taxodione (2), as well as the semisynthetic derivatives 12, 14, 15, 17, and 22, were the most cytotoxic compounds for human leukemia cells. Overexpression of the protective mitochondrial proteins Bcl-2 and Bcl-x(L) did not confer resistance to abietane diterpene-induced cytotoxicity. Studies performed on HL-60 cells indicated that growth inhibition triggered by compounds 1, 12, 14, and 15 was caused by induction of apoptosis. This was prevented by the nonspecific caspase inhibitor Z-VAD-FMK and, in the case of compounds 14 and 15, reduced by the selective caspase-8 inhibitor Z-IETD-FMK. Cell death induced by these abietane diterpenes was found to be associated with the release of mitochondrial proteins, including cytochrome c, Smac/DIABLO, and AIF (apoptosis-inducing factor), accompanied by dissipation of the mitochondrial membrane potential (ΔΨ), and modulated by inhibition of extracellular signal-regulated kinases signaling and the p38 mitogen-activated protein kinase pathway.
- Published
- 2013
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46. Development of a method to investigate the hydrolysis of xenobiotic esters by a Mycobacterium smegmatis homogenate.
- Author
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Valente E, Simões MF, Testa B, and Constantino L
- Subjects
- Esters chemistry, Hydrolysis, Kinetics, Mycobacterium smegmatis chemistry, Prodrugs chemistry, Xenobiotics chemistry, Bacteriological Techniques methods, Esters metabolism, Mycobacterium smegmatis metabolism, Prodrugs metabolism, Xenobiotics metabolism
- Abstract
One of the main problems in combating tuberculosis is caused by a poor penetration of drugs into the mycobacterial cells. A prodrug approach via activation inside mycobacterial cells is a possible strategy to overcome this hurdle and achieve efficient drug uptake. Esters are attractive candidates for such a strategy and we and others communicated previously the activity of esters of weak organic acids against mycobacteria. However very little is known about ester hydrolysis by mycobacteria and no biological model is available to study the activation of prodrugs by these microorganisms. To begin filling this gap, we have embarked in a project to develop an in vitro method to study prodrug activation by mycobacteria using Mycobacterium smegmatis homogenates. Model ester substrates were ethyl nicotinate and ethyl benzoate whose hydrolysis was monitored and characterized kinetically. Our studies showed that in M. smegmatis most esterase activity is associated with the soluble fraction (cytosol) and is preserved by storage at 5°C or at room temperature for one hour, or by storage at -80°C up to one year. In the range of homogenate concentrations studied (5-80% in buffer), k(obs) varied linearly with homogenate concentration for both substrates. We also found that the homogenates showed Michaelis-Menten kinetics behavior with both prodrugs. Since ethyl benzoate is a good substrate for the mycobacterial esterases, this compound can be used to standardize the esterasic activity of homogenates, allowing results of incubations of prodrugs with homogenates from different batches to be readily compared., (Copyright © 2011 Elsevier B.V. All rights reserved.)
- Published
- 2011
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47. Antimycobacterial metabolites from Plectranthus: royleanone derivatives against Mycobacterium tuberculosis strains.
- Author
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Rijo P, Simões MF, Francisco AP, Rojas R, Gilman RH, Vaisberg AJ, Rodríguez B, and Moiteiro C
- Subjects
- 3T3 Cells, Abietanes isolation & purification, Abietanes toxicity, Animals, Anti-Bacterial Agents isolation & purification, Anti-Bacterial Agents toxicity, Chlorocebus aethiops, Drug Resistance, Multiple, Bacterial drug effects, Mice, Microbial Sensitivity Tests, Plectranthus chemistry, Vero Cells, Abietanes chemistry, Anti-Bacterial Agents chemistry, Mycobacterium tuberculosis drug effects, Plectranthus metabolism
- Abstract
The antimycobacterial activities of eight diterpenes, 1-8, isolated previously from Plectranthus and eleven esters, 9-19, of 7alpha-acetoxy-6beta,12-dihydroxyabieta-8,12-diene-11,14-dione (5) were evaluated against the MTB strains H(37)Rv and MDR. Only diterpenoids with a quinone framework revealed anti-MTB activity. Abietane 5 and its 6,12-dibenzoyl, 12-methoxybenzoyl, 12-chlorobenzoyl, and 12-nitrobenzoyl esters, 9, 11, 12, and 13, respectively, showed potent activities against the MDR strain with MIC values between 3.12 and 0.39 microg/ml. Cytotoxic activities towards 3T3 and Vero cells were also evaluated. Compound 11, with the best selectivity index, may be a suitable lead for further chemical modifications. The complete structural elucidation of the new esters, 9-14, 16, 18, and 19, as well as the NMR data of known derivatives 15 and 17 are reported.
- Published
- 2010
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48. How do cognitive and axial motor signs correlate in Parkinson's disease? A 6-year prospective study.
- Author
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Gago MF, Garrett MC, Fonseca MR, Rosas MJ, Simões MF, Vieira S, and Botelho F
- Subjects
- Cohort Studies, Disease Progression, Female, Follow-Up Studies, Humans, Male, Middle Aged, Neuropsychological Tests, Prospective Studies, Severity of Illness Index, Speech Disorders epidemiology, Dementia epidemiology, Dyskinesias epidemiology, Parkinson Disease epidemiology
- Abstract
Impairment of Parkinson's disease (PD) axial motor signs (AMS) has been described as a risk factor for dementia. Executive dysfunction is an important feature in recently proposed clinical diagnostic criteria for PD dementia. To clarify the relationship between AMS progression and executive cognitive performance, we conducted a 6-year prospective study in PD patients without AMS impairment at baseline. A hospital-based cohort of PD patients (n = 24) without dementia, in the initial motor stage (Hoehn-Yahr < or = 2), and matched controls (n = 20) were followed prospectively over a 6-year period. Neuropsychological tests were performed in both groups, and motor function (including AMS: speech, gait, postural instability) was evaluated in the PD group. The PD group had a significantly higher decline in neuropsychological test scores than did the controls. Most of the neuropsychological and motor decline occurred in the last 4 years. In UPDRS III, progression of AMS and especially speech were the most important motor variables related to dementia. There was a correlation between speech impairment progression and declines in MMSE (r = -0.598, p = 0.002), Clock Drawing (r = -0.671, p < 0.001), Semantic Verbal Fluency (r = -0.435, p = 0.034), Alternating Sequences (r = 0.497, p = 0.014), and Raven's Coloured Progressive Matrices (r = -0.735, p < 0.001). PD patients with higher speech impairment progression showed more rapid declines in some neuropsychological tests. Further studies are needed to clarify the different roles of speech, gait and postural instability on the initial phases of cognitive dysfunction.
- Published
- 2009
- Full Text
- View/download PDF
49. Selective activation of protein kinase C-delta and -epsilon by 6,11,12,14-tetrahydroxy-abieta-5,8,11,13-tetraene-7-one (coleon U).
- Author
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Coutinho I, Pereira G, Simões MF, Côrte-Real M, Gonçalves J, and Saraiva L
- Subjects
- Animals, Apoptosis drug effects, Cell Cycle drug effects, Cell Division drug effects, Enzyme Activation, Rats, Saccharomyces cerevisiae cytology, Saccharomyces cerevisiae drug effects, Diterpenes pharmacology, Enzyme Activators pharmacology, Protein Kinase C-delta metabolism, Protein Kinase C-epsilon metabolism
- Abstract
6,11,12,14-tetrahydroxy-abieta-5,8,11,13-tetraene-7-one (coleon U) is a diterpene compound isolated from Plectranthus grandidentatus with an antiproliferative effect on several human cancer cell lines. Herein, we studied the modulatory activity of coleon U on individual isoforms of the three protein kinase C (PKC) subfamilies, classical (cPKC-alpha and -betaI), novel (nPKC-delta and -epsilon) and atypical (aPKC-zeta), using a yeast PKC assay. The results showed that, whereas the PKC activator phorbol-12-myristate-13-acetate (PMA) activated every PKC tested except aPKC, coleon U had no effect on aPKC and cPKCs. Besides, the effect of coleon U on nPKCs was higher than that of PMA. This revealed that coleon U was a potent and selective activator of nPKCs. The isoform-selectivity of coleon U for nPKC-delta and -epsilon was confirmed using an in vitro PKC assay. Most importantly, while PMA activated nPKCs inducing an isoform translocation from the cytosol to the plasma membrane and a G2/M cell cycle arrest, coleon U induced nPKCs translocation to the nucleus and a metacaspase- and mitochondrial-dependent apoptosis. This work therefore reconstitutes in yeast distinct subcellular translocations of a PKC isoform and the subsequent distinct cellular responses reported for mammalian cells. Together, our study identifies a new isoform-selective PKC activator with promising pharmacological applications. Indeed, since coleon U has no effect on cPKCs and aPKC, recognised as anti-apoptotic proteins, and selectively induces an apoptotic pathway dependent on nPKC-delta and -epsilon activation, it represents a promising compound for evaluation as an anti-cancer drug.
- Published
- 2009
- Full Text
- View/download PDF
50. Lipophilic pyrazinoic acid amide and ester prodrugs stability, activation and activity against M. tuberculosis.
- Author
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Simões MF, Valente E, Gómez MJ, Anes E, and Constantino L
- Subjects
- Amides chemical synthesis, Amides chemistry, Amides pharmacology, Animals, Antitubercular Agents chemical synthesis, Buffers, Cell Line, Chromatography, High Pressure Liquid, Drug Stability, Esters chemical synthesis, Esters chemistry, Esters pharmacology, Humans, Hydrolysis, In Vitro Techniques, Indicators and Reagents, Lipids chemistry, Liver metabolism, Macrophages drug effects, Microbial Sensitivity Tests, Mycobacterium smegmatis drug effects, Mycobacterium tuberculosis enzymology, Phagocytosis drug effects, Prodrugs chemical synthesis, Pyrazinamide chemical synthesis, Pyrazinamide chemistry, Pyrazinamide pharmacology, Rats, Solubility, Solutions, Spectrophotometry, Ultraviolet, Antitubercular Agents chemistry, Antitubercular Agents pharmacology, Mycobacterium tuberculosis drug effects, Prodrugs chemistry, Pyrazinamide analogs & derivatives
- Abstract
Pyrazinamide (PZA) is active against M. tuberculosis and is a first line agent for the treatment of human tuberculosis. PZA is itself a prodrug that requires activation by a pyrazinamidase to form its active metabolite pyrazinoic acid (POA). Since the specificity of cleavage is dependent on a single bacterial enzyme, resistance to PZA is often found in tuberculosis patients. Esters of POA have been proposed in the past as alternatives to PZA however the most promising compounds were rapidly degraded in the presence of serum. In order to obtain compounds that could survive during the transport phase, we synthesized lipophilic ester and amide POA derivatives, studied their activity against M. tuberculosis, their stability in plasma and rat liver homogenate and also their activation by a mycobacterial homogenate. The new lipophilic ester prodrugs were found to be active in concentrations 10-fold lower than those needed for PZA to kill sensitive M. tuberculosis and also have a suitable stability in the presence of plasma. Amides of POA although more stable in plasma have lower activity. The reason can probably be found in the rate of activation of both types of prodrugs; while esters are easily activated by mycobacterial esterases, amides are resistant to activation and are not transformed into POA at a suitable rate.
- Published
- 2009
- Full Text
- View/download PDF
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