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  1. Article ; Online: Impact of virus genetic variability and host immunity for the success of COVID-19 vaccines.

    Dos Santos, Wagner Gouvêa

    Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie

    2021  Volume 136, Page(s) 111272

    Abstract: Coronavirus disease 19 (COVID-19) continues to challenge most scientists in the search of an effective way to either prevent infection or to avoid spreading of the disease. As result of global efforts some advances have been reached and we are more ... ...

    Abstract Coronavirus disease 19 (COVID-19) continues to challenge most scientists in the search of an effective way to either prevent infection or to avoid spreading of the disease. As result of global efforts some advances have been reached and we are more prepared today than we were at the beginning of the pandemic, however not enough to stop the transmission, and many questions remain unanswered. The possibility of reinfection of recovered individuals, the duration of the immunity, the impact of SARS-CoV-2 mutations in the spreading of the disease as well as the degree of protection that a potential vaccine could have are some of the issues under debate. A number of vaccines are under development using different platforms and clinical trials are ongoing in different countries, but even if they are licensed it will need time until reach a definite conclusion about their real safety and efficacy. Herein we discuss the different strategies used in the development of COVID-19 vaccines, the questions underlying the type of immune response they may elicit, the consequences that new mutations may have in the generation of sub-strains of SARS-CoV-2 and their impact and challenges for the efficacy of potential vaccines in a scenario postpandemic.
    MeSH term(s) COVID-19/prevention & control ; COVID-19/virology ; COVID-19 Vaccines/immunology ; Genetic Variation ; Humans ; Immunity, Humoral/genetics ; SARS-CoV-2/genetics
    Chemical Substances COVID-19 Vaccines
    Language English
    Publishing date 2021-01-12
    Publishing country France
    Document type Journal Article ; Review
    ZDB-ID 392415-4
    ISSN 1950-6007 ; 0753-3322 ; 0300-0893
    ISSN (online) 1950-6007
    ISSN 0753-3322 ; 0300-0893
    DOI 10.1016/j.biopha.2021.111272
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Natural history of COVID-19 and current knowledge on treatment therapeutic options.

    Dos Santos, Wagner Gouvea

    Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie

    2020  Volume 129, Page(s) 110493

    Abstract: Despite intense research there is currently no effective vaccine available against the new severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) emerged in the later 2019 and responsible for the COVID-19 pandemic. This infectious and communicable ... ...

    Abstract Despite intense research there is currently no effective vaccine available against the new severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) emerged in the later 2019 and responsible for the COVID-19 pandemic. This infectious and communicable disease has become one of the major public health challenges in the world. The clinical management of COVID-19 has been limited to infection prevention and control measures associated with supportive care such as supplemental oxygen and mechanical ventilation. Meanwhile efforts to find an effective treatment to inhibit virus replication, mitigate the symptoms, increase survival and decrease mortality rate are ongoing. Several classes of drugs, many of them already in use for other diseases, are being evaluated based on the body of clinical knowledge obtained from infected patients regarding to the natural history and evolution of the infection. Herein we will provide an updated overview of the natural history and current knowledge on drugs and therapeutic agents being tested for the prevention and treatment of COVID-19. These include different classes of drugs such as antiviral agents (chloroquine, ivermectin, nitazoxanide, hydroxychloroquine, lopinavir, remdesivir, tocilizumab), supporting agents (Vitamin C, Vitamin D, azithromycin, corticosteroids) and promising investigational vaccines. Considering the controversies and excessive number of compounds being tested and reported in the literature we hope that this review can provide useful and updated consolidated information on potential drugs used to prevent, control and treat COVID-19 patients worldwide.
    MeSH term(s) Animals ; Antiviral Agents/pharmacology ; Betacoronavirus/drug effects ; Betacoronavirus/isolation & purification ; COVID-19 ; Coronavirus Infections/drug therapy ; Coronavirus Infections/epidemiology ; Coronavirus Infections/virology ; Drug Design ; Humans ; Pandemics ; Pneumonia, Viral/drug therapy ; Pneumonia, Viral/epidemiology ; Pneumonia, Viral/virology ; Public Health ; SARS-CoV-2 ; Viral Vaccines/administration & dosage ; COVID-19 Drug Treatment
    Chemical Substances Antiviral Agents ; Viral Vaccines
    Keywords covid19
    Language English
    Publishing date 2020-07-03
    Publishing country France
    Document type Journal Article ; Review
    ZDB-ID 392415-4
    ISSN 1950-6007 ; 0753-3322 ; 0300-0893
    ISSN (online) 1950-6007
    ISSN 0753-3322 ; 0300-0893
    DOI 10.1016/j.biopha.2020.110493
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Natural history of COVID-19 and current knowledge on treatment therapeutic options

    dos Santos, Wagner Gouvea

    Biomedicine & Pharmacotherapy

    2020  Volume 129, Page(s) 110493

    Keywords Pharmacology ; General Medicine ; covid19
    Language English
    Publisher Elsevier BV
    Publishing country us
    Document type Article ; Online
    ZDB-ID 392415-4
    ISSN 1950-6007 ; 0753-3322 ; 0300-0893
    ISSN (online) 1950-6007
    ISSN 0753-3322 ; 0300-0893
    DOI 10.1016/j.biopha.2020.110493
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  4. Article: Natural history of COVID-19 and current knowledge on treatment therapeutic options

    Dos Santos, Wagner Gouvea

    Biomed Pharmacother

    Abstract: Despite intense research there is currently no effective vaccine available against the new severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) emerged in the later 2019 and responsible for the COVID-19 pandemic. This infectious and communicable ... ...

    Abstract Despite intense research there is currently no effective vaccine available against the new severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) emerged in the later 2019 and responsible for the COVID-19 pandemic. This infectious and communicable disease has become one of the major public health challenges in the world. The clinical management of COVID-19 has been limited to infection prevention and control measures associated with supportive care such as supplemental oxygen and mechanical ventilation. Meanwhile efforts to find an effective treatment to inhibit virus replication, mitigate the symptoms, increase survival and decrease mortality rate are ongoing. Several classes of drugs, many of them already in use for other diseases, are being evaluated based on the body of clinical knowledge obtained from infected patients regarding to the natural history and evolution of the infection. Herein we will provide an updated overview of the natural history and current knowledge on drugs and therapeutic agents being tested for the prevention and treatment of COVID-19. These include different classes of drugs such as antiviral agents (chloroquine, ivermectin, nitazoxanide, hydroxychloroquine, lopinavir, remdesivir, tocilizumab), supporting agents (Vitamin C, Vitamin D, azithromycin, corticosteroids) and promising investigational vaccines. Considering the controversies and excessive number of compounds being tested and reported in the literature we hope that this review can provide useful and updated consolidated information on potential drugs used to prevent, control and treat COVID-19 patients worldwide.
    Keywords covid19
    Publisher WHO
    Document type Article
    Note WHO #Covidence: #626324
    Database COVID19

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  5. Article ; Online: Neutron activation increases activity of ruthenium-based complexes and induces cell death in glioma cells independent of p53 tumor suppressor gene.

    Montel, Aline Monezi / Dos Santos, Raquel Gouvêa / da Costa, Pryscila Rodrigues / Silveira-Lacerda, Elisângela de Paula / Batista, Alzir Azevedo / Dos Santos, Wagner Gouvêa

    Biometals : an international journal on the role of metal ions in biology, biochemistry, and medicine

    2017  Volume 30, Issue 2, Page(s) 295–305

    Abstract: Novel metal complexes have received great attention in the last decades due to their potential anticancer activity. Notably, ruthenium-based complexes have emerged as good alternative to the currently used platinum-based drugs for cancer therapy, ... ...

    Abstract Novel metal complexes have received great attention in the last decades due to their potential anticancer activity. Notably, ruthenium-based complexes have emerged as good alternative to the currently used platinum-based drugs for cancer therapy, providing less toxicity and side effects to patients. Glioblastoma is an aggressive and invasive type of brain tumor and despite of advances is the field of neurooncology there is no effective treatment until now. Therefore, we sought to investigate the potential antiproliferative activity of phosphine-ruthenium-based complexes on human glioblastoma cell lines. Due to its octahedral structure as opposed to the square-planar geometry of platinum(II) compounds, ruthenium(II) complexes exhibit different structure-function relationship probably acting through a different mechanism from that of cisplatin beyond their ability to bind DNA. To better improve the pharmacological activity of metal complexes we hypothesized that neutron activation of ruthenium in the complexes would allow to decrease the effective concentration of the compound needed to kill tumor cells. Herein we report on the effect of unmodified and neutron activated phosphine ruthenium II complexes on glioblastoma cell lines carrying wild-type and mutated p53 tumor suppressor gene. Induction of apoptosis/authophagy as well as generation of reactive oxygen species were determined. The phosphine ruthenium II complexes tested were highly active against glioblastoma cell lines inducing cell death both through apoptosis and autophagy in a p53 independent fashion. Neutron activation of ruthenium compounds rendered them more active than their original counterparts suggesting a new strategy to improve the antitumor activity of these compounds.
    Language English
    Publishing date 2017-04
    Publishing country Netherlands
    Document type Journal Article
    ZDB-ID 1112688-7
    ISSN 1572-8773 ; 0966-0844
    ISSN (online) 1572-8773
    ISSN 0966-0844
    DOI 10.1007/s10534-017-0006-1
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Simulations of complex and microscopic models of cardiac electrophysiology powered by multi-GPU platforms.

    Gouvêa de Barros, Bruno / Sachetto Oliveira, Rafael / Meira, Wagner / Lobosco, Marcelo / Weber dos Santos, Rodrigo

    Computational and mathematical methods in medicine

    2012  Volume 2012, Page(s) 824569

    Abstract: Key aspects of cardiac electrophysiology, such as slow conduction, conduction block, and saltatory effects have been the research topic of many studies since they are strongly related to cardiac arrhythmia, reentry, fibrillation, or defibrillation. ... ...

    Abstract Key aspects of cardiac electrophysiology, such as slow conduction, conduction block, and saltatory effects have been the research topic of many studies since they are strongly related to cardiac arrhythmia, reentry, fibrillation, or defibrillation. However, to reproduce these phenomena the numerical models need to use subcellular discretization for the solution of the PDEs and nonuniform, heterogeneous tissue electric conductivity. Due to the high computational costs of simulations that reproduce the fine microstructure of cardiac tissue, previous studies have considered tissue experiments of small or moderate sizes and used simple cardiac cell models. In this paper, we develop a cardiac electrophysiology model that captures the microstructure of cardiac tissue by using a very fine spatial discretization (8 μm) and uses a very modern and complex cell model based on Markov chains for the characterization of ion channel's structure and dynamics. To cope with the computational challenges, the model was parallelized using a hybrid approach: cluster computing and GPGPUs (general-purpose computing on graphics processing units). Our parallel implementation of this model using a multi-GPU platform was able to reduce the execution times of the simulations from more than 6 days (on a single processor) to 21 minutes (on a small 8-node cluster equipped with 16 GPUs, i.e., 2 GPUs per node).
    MeSH term(s) Algorithms ; Cardiac Electrophysiology/methods ; Computer Graphics ; Computer Simulation ; Electric Conductivity ; Finite Element Analysis ; Gap Junctions/physiology ; Heart/physiology ; Humans ; Markov Chains ; Models, Cardiovascular ; Models, Theoretical ; Myocardium/metabolism ; Software ; Time Factors
    Language English
    Publishing date 2012-11-25
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2252430-7
    ISSN 1748-6718 ; 1748-670X ; 1027-3662
    ISSN (online) 1748-6718
    ISSN 1748-670X ; 1027-3662
    DOI 10.1155/2012/824569
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Simulations of Complex and Microscopic Models of Cardiac Electrophysiology Powered by Multi-GPU Platforms

    Bruno Gouvêa de Barros / Rafael Sachetto Oliveira / Wagner Meira / Marcelo Lobosco / Rodrigo Weber dos Santos

    Computational and Mathematical Methods in Medicine, Vol

    2012  Volume 2012

    Abstract: Key aspects of cardiac electrophysiology, such as slow conduction, conduction block, and saltatory effects have been the research topic of many studies since they are strongly related to cardiac arrhythmia, reentry, fibrillation, or defibrillation. ... ...

    Abstract Key aspects of cardiac electrophysiology, such as slow conduction, conduction block, and saltatory effects have been the research topic of many studies since they are strongly related to cardiac arrhythmia, reentry, fibrillation, or defibrillation. However, to reproduce these phenomena the numerical models need to use subcellular discretization for the solution of the PDEs and nonuniform, heterogeneous tissue electric conductivity. Due to the high computational costs of simulations that reproduce the fine microstructure of cardiac tissue, previous studies have considered tissue experiments of small or moderate sizes and used simple cardiac cell models. In this paper, we develop a cardiac electrophysiology model that captures the microstructure of cardiac tissue by using a very fine spatial discretization (8 μm) and uses a very modern and complex cell model based on Markov chains for the characterization of ion channel’s structure and dynamics. To cope with the computational challenges, the model was parallelized using a hybrid approach: cluster computing and GPGPUs (general-purpose computing on graphics processing units). Our parallel implementation of this model using a multi-GPU platform was able to reduce the execution times of the simulations from more than 6 days (on a single processor) to 21 minutes (on a small 8-node cluster equipped with 16 GPUs, i.e., 2 GPUs per node).
    Keywords Computer applications to medicine. Medical informatics ; R858-859.7
    Subject code 612 ; 000
    Language English
    Publishing date 2012-01-01T00:00:00Z
    Publisher Hindawi Limited
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  8. Article ; Online: Controle do tombamento de plântulas de beterraba e tomate pelo tratamento de sementes com quitosana Control of beet and tomato damping-off by seed treatment with chitosan

    Sérgio Miguel Mazaro / Américo Wagner Júnior / Idalmir dos Santos / Idemir Citadin / Jean Carlo Possenti / Alfredo de Gouvêa

    Pesquisa Agropecuária Brasileira, Vol 44, Iss 11, Pp 1424-

    2009  Volume 1430

    Abstract: O objetivo deste trabalho foi avaliar o efeito do tratamento de sementes, com o indutor de resistência quitosana, sobre o tombamento de plântulas de beterraba e tomate, e sua relação com alterações bioquímicas e a defesa vegetal. Cada parcela foi ... ...

    Abstract O objetivo deste trabalho foi avaliar o efeito do tratamento de sementes, com o indutor de resistência quitosana, sobre o tombamento de plântulas de beterraba e tomate, e sua relação com alterações bioquímicas e a defesa vegetal. Cada parcela foi representada por 25 sementes. Os tratamentos consistiram da imersão das sementes em quitosana nas concentrações de 0; 0,25; 0,5; 1; 2 e 4%. Posteriormente, as sementes foram semeadas em bandejas com o substrato infectado com Rhizoctonia sp., e mantidas em casa de vegetação por 14 dias. A quitosana induziu a resistência das plântulas de beterraba e tomate e reduziu a incidência de tombamento. As concentrações de 1,1 e 2,5% apresentaram maior eficiência na redução do tombamento, para as culturas da beterraba e tomate, respectivamente. O uso da quitosana induz o aumento na atividade da enzima fenilalanina amônia-liase (FAL) e interfere nas variáveis bioquímicas foliares de proteínas e açúcares totais e redutores. The objective of this study was to evaluate the effect of seed treatment using the resistance inductor chitosan to control damping-off in tomato and beet seedlings, and its relationship with plant biochemical alterations and plant protection. Each plot was represented by twenty-five seeds. Treatments consisted of seed immersion in a chitosan suspension at 0, 0.25, 0.5, 1, 2 and 4% concentrations. Seeds were then sowed in trays with a substrate infected with Rhizoctonia sp. and maintained in greenhouse conditions for 14 days. Chitosan induced seedling resistance and reduced damping-off. The 1.1 and 2.5% concentrations were more efficient in controling the damping-off for beet and tomato crops respectively. Chitosan increases the phenylalanine ammonialyase (PAL) activity and interferes with the total proteins and total and reduced sugars rates in the leaves.
    Keywords indução de resistência ; proteínas relacionadas à patogênese ; tombamento de plântulas ; systemic acquired resistance ; pathogenesis-related proteins ; damping-off ; Agriculture (General) ; S1-972
    Language English
    Publishing date 2009-11-01T00:00:00Z
    Publisher Embrapa Informação Tecnológica
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  9. Article: Controle do tombamento de plântulas de beterraba e tomate pelo tratamento de sementes com quitosana

    Mazaro, Sérgio Miguel(Universidade Tecnológica Federal do Paraná) / Wagner Júnior, Américo(Universidade Tecnológica Federal do Paraná) / Santos, Idalmir dos / Citadin, Idemir / Possenti, Jean Carlo(Universidade Tecnológica Federal do Paraná) / Gouvêa, Alfredo de(Universidade Tecnológica Federal do Paraná)

    Pesquisa Agropecuária Brasileira

    2009/11  

    Abstract: O objetivo deste trabalho foi avaliar o efeito do tratamento de sementes, com o indutor de resistência quitosana, sobre o tombamento de plântulas de beterraba e tomate, e sua relação com alterações bioquímicas e a defesa vegetal. Cada parcela foi ... ...

    Abstract O objetivo deste trabalho foi avaliar o efeito do tratamento de sementes, com o indutor de resistência quitosana, sobre o tombamento de plântulas de beterraba e tomate, e sua relação com alterações bioquímicas e a defesa vegetal. Cada parcela foi representada por 25 sementes. Os tratamentos consistiram da imersão das sementes em quitosana nas concentrações de 0; 0,25; 0,5; 1; 2 e 4%. Posteriormente, as sementes foram semeadas em bandejas com o substrato infectado com Rhizoctonia sp., e mantidas em casa de vegetação por 14 dias. A quitosana induziu a resistência das plântulas de beterraba e tomate e reduziu a incidência de tombamento. As concentrações de 1,1 e 2,5% apresentaram maior eficiência na redução do tombamento, para as culturas da beterraba e tomate, respectivamente. O uso da quitosana induz o aumento na atividade da enzima fenilalanina amônia-liase (FAL) e interfere nas variáveis bioquímicas foliares de proteínas e açúcares totais e redutores.
    Language Portuguese
    Document type Article
    ISSN 0100-204X
    Database AGRIS - International Information System for the Agricultural Sciences and Technology

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