112 results on '"Ivan Brito"'
Search Results
2. Crystal structure and Hirshfeld surface analysis of 1-(2-amino-4-methyl-1,3-thiazol-5-yl)ethan-1-one
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Elnur Z. Huseynov, Mehmet Akkurt, Ivan Brito, Ajaya Bhattarai, Rovnag M. Rzayev, Khammed A. Asadov, and Abel M. Maharramov
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crystal structure ,thiazole derivatives ,hydrogen bonds ,dimers ,hirshfeld surface analysis ,Crystallography ,QD901-999 - Abstract
In the title compound, C6H8N2OS, all atoms except for the methyl H atoms are coplanar, with a maximum deviation of 0.026 (4) Å. In the crystal, pairs of molecules are linked by N—H...N hydrogen bonds, forming R22(8) ring motifs. Dimers are connected by N—H...O hydrogen bonds, forming layers parallel to the (102) plane. Consolidating the molecular packing, these layers are connected by C—H...π interactions between the center of the 1,3-thiazole ring and the H atom of the methyl group attached to it, as well as C=O...π interactions between the center of the 1,3-thiazole ring and the O atom of the carboxyl group. According to a Hirshfeld surface study, H...H (37.6%), O...H/H...O (16.8%), S...H/H...S (15.4%), N...H/H...N (13.0%) and C...H/H...C (7.6%) interactions are the most significant contributors to the crystal packing.
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- 2023
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3. Crystal structure and Hirshfeld surface analysis of 2-amino-5-{(1E)-1-[(carbamothioylamino)imino]ethyl}-4-methyl-1,3-thiazol-3-ium chloride monohydrate
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Elnur Z. Huseynov, Mehmet Akkurt, Ivan Brito, Ajaya Bhattarai, Farid N. Naghiyev, Khammed A. Asadov, and Abel M. Maharramov
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crystal structure ,1,3-thiazol-3-ium ,hydrogen bonds ,hydrogen-bonded network ,hirshfeld surface analysis ,Crystallography ,QD901-999 - Abstract
In the hydrated title salt, C7H12N5S2+·Cl−·H2O, the asymmetric unit comprises one 2-amino-5-{(1E)-1-[(carbamothioylamino)imino]ethyl}-4-methyl-1,3-thiazol-3-ium cation, one chloride anion and one water molecule of crystallization. The cation is nearly flat (r.m.s. deviation of non-H atoms is 0.0814 Å), with the largest deviation of 0.1484 (14) Å observed for one of the methyl C atoms. In the crystal, the cations are linked by O—H...Cl, N—H...Cl, N—H...O, N—H...S and C—H...S hydrogen bonds, forming a tri-periodic network. The most important contributions to the crystal packing are from H...H (35.4%), S...H/H...S (24.4%), N...H/H...N (8.7%), Cl...H/H...Cl (8.2%) and C...H/H...C (7.7%) interactions.
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- 2023
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4. Enhancing c-Si Solar Cell Efficiency in the UV Region: Photophysical Insights into the Use of Eu3+ Complexes for Down-Shifting Layer Applications
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Fabian Vargas, Ronald Nelson, Dario Espinoza, Ivan Brito, Laura Sánchez-Muñoz, Pere Alemany, Sergio Ortiz, Pablo Ferrada, Alifhers Mestra, and Jaime Llanos
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europium complex ,c-Si solar cell ,luminescent down-shifting layer ,synthesis and characterization methods for optoelectronic materials ,Organic chemistry ,QD241-441 - Abstract
[Eu(3DPIQC)3] (where DPIQC = 3-(diphenyl phosphoryl)-1-isoquinolinecarboxylate), a luminescent europium complex with antenna ligands, has been carefully embedded within a polyvinyl butyral (PVB) matrix and the resulting material was used to prepare films used as luminescent down-shifting layers (LDSLs) for crystalline Si-based solar cells. The films were characterized using photoluminescence spectroscopy, atomic force spectroscopy (AFM), UV-Vis spectroscopy, and fluorescence microscopy. The AFM analysis shows films with low surface roughness, while fluorescence microscopy revealed that the Eu complex embedded in PVB assumed a spheroidal configuration, a morphology especially beneficial for optical applications. The so-obtained LDSLs were utilized as energy converters in c-Si solar cells to enhance the utilization of high-energy photons, thereby improving their overall efficiency. The determination of photovoltaic parameters carried out before and after the deposition of the LDSLs on the c-Si cells confirms a positive effect on the efficiency of the cell. The Jsc increases from 121.6 mA/cm2 to 124.9 mA/cm2, and the open circuit voltage (Voc) is found to be unrelated to the complex concentration in the films. The fill factor (FF) remains constant with the Eu concentration. The EQE curves indicate an enhancement in the performance of the photovoltaic cells within the UV region of the spectrum for all coated devices. Electrochemical impedance spectroscopy (EIS) was also carried out in order to analyze the effect of the Eu complex in the charge transfer process of the devices.
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- 2023
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5. Immunomodulating effects of Phlebotomine saliva in Leishmania infection: Review
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Ivan Brito Feitosa, Wesley Roberto de Aguida, and Carolina Bioni Garcia Teles
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leishmania ,lutzomyia ,phlebotomus ,sandflies ,saliva ,protection ,flebótomos ,proteção ,Ecology ,QH540-549.5 ,Botany ,QK1-989 ,Zoology ,QL1-991 - Abstract
Abstract. The recognized action of some proteins present in the saliva of the phlebotomine dipteran vectors of Leishmaniasis, as modulators of the hemostatic, inflammatory and immune responses during the colonization of the protozoan in the host organism, created the expectation of formulating a vaccine against this disease. The present study aimed to provide an overview about researchs that deals with the role of phlebotomine saliva in Leishmania infections. A bibliographic search was carried out in PubMed, SciELO and LILACS databases. The articles listed address the following aspects of the vector’s saliva: intensification of infection; suppression and modulation of the host immune system; chemotaxis on phagocytic cells; induction of innate and adaptive immunity; isolation and characterization of immunoactive molecules and their possible protective function against Leishmaniasis. Efeitos imunomoduladores da saliva de flebotomínio na infecção por Leishmania: Revisão Resumo. A reconhecida ação de algumas proteínas presentes na saliva dos vetores flebotomíneos da Leishmaniose, como moduladores das respostas hemostáticas, inflamatórias e imunes durante a colonização do protozoário no organismo hospedeiro, criou a expectativa de formular uma vacina contra essa doença. O presente estudo teve como objetivo fornecer uma visão geral sobre pesquisas que abordam o papel da saliva de flebotomíneos em infecções por Leishmania. Foi realizada uma pesquisa bibliográfica nas bases de dados PubMed, SciELO e LILACS. Os artigos listados abordam os seguintes aspectos da saliva do vetor: intensificação da infecção; supressão e modulação do sistema imune do hospedeiro; quimiotaxia em células fagociticas; indução da imunidade inata e adaptativa; isolamento e caracterização de moléculas imunoativas e sua possível função protetora contra a leishmaniose.
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- 2018
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6. Crystal Structure and Hirshfeld Surface Analysis of Acetoacetanilide Based Reaction Products
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Farid N. Naghiyev, Jonathan Cisterna, Ali N. Khalilov, Abel M. Maharramov, Rizvan K. Askerov, Khammed A. Asadov, Ibrahim G. Mamedov, Khaver S. Salmanli, Alejandro Cárdenas, and Ivan Brito
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acetoacetanilide ,multicomponent reaction ,X-ray analysis ,Hirshfeld surface analysis ,Organic chemistry ,QD241-441 - Abstract
We report an unprecedented multicomponent reaction of acetoacetanilide with malononitrile leading to a structurally novel bicyclic product (9) in a high yield. The structure has been confirmed by X-ray crystallography and comparative Hirshfeld surface analysis of 5-cyano-2-hydroxy-2-methyl-N-phenyl-4-(yridine-4-yl)-6-(thiophen-2-yl)-3,4-dihydro-2H-pyran-3-carboxamide 2, 5-cyano-2-hydroxy-2-methyl-6-oxo-N-phenyl-4-(thiophen-2-yl)piperidine-3-carboxamide 4 and 2-(8-amino-7,8a-dicyano-1-imino-4a-methyl-3-oxo-2-phenyl-1,3,4,4a,5,8a-hexahydroisoquinolin-6(2H)-ylidene)-N-phenylacetamide 9.
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- 2020
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7. (-)-Shikimic Acid as a Chiral Building Block for the Synthesis of New Cytotoxic 6-Aza-Analogues of Angucyclinones
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Natalia Quiñones, Santiago Hernández, Luis Espinoza Catalán, Joan Villena, Ivan Brito, Alan R. Cabrera, Cristian O. Salas, and Mauricio A. Cuellar
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(-)-Shikimic acid ,angucyclinone derivatives ,hetero-Diels-Alder ,cytotoxicity ,cancer cell lines ,Organic chemistry ,QD241-441 - Abstract
We describe the syntheses of nine new angucyclinone 6-aza-analogues, achieved through a hetero Diels-Alder reaction between the shikimic acid derivative-azadiene 13, with different naphthoquinones. The cytotoxic activity of the new synthesized compounds and five angucyclinones, previously reported, was evaluated in vitro against three cancer cell lines: PC-3 (prostate cancer), HT-29 (colon cancer), MCF-7 (breast cancer), and one non-tumoral cell line, human colon epithelial cells (CCD841 CoN). Our results showed that most 6-azadiene derivatives exhibited significant cytotoxic activities, which was demonstrated by their IC50 values (less than 10 μM), especially for the most sensitive cells, PC-3 and HT-29. From a chemical point of view, depending on the protected group of ring A and the pattern of substitution on ring D, cytotoxicity elicited these compounds, in terms of their potency and selectivity. Therefore, according to these chemical features, the most promising agents for every cancer cell line were 7a, 17, and 19c for PC-3 cells; 7a, 17, and 20 for HT-29 cells, and 19a for MCF-7 cells.
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- 2018
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8. UMA ANÁLISE SOBRE O ASTROVÍRUS
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Silva, Thiago Christian da, primary, Feitosa, Ivan Brito, additional, and Jankowitsch, Jhonata, additional
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- 2023
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9. ATIVIDADE DOS MACRÓFAGOS NAS DOENÇAS ATEROSCLERÓTICAS: UM PANORAMA GERAL
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Rocha, Renata Maria, primary, Sena, Thássia Christina de Souza, additional, Grabner, Kamila Klegues Cidade, additional, Lacerda, Manuela Estrela do Ó, additional, Maciel, Victor Mota, additional, and Feitosa, Ivan Brito, additional
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- 2022
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10. What are the immune responses during the growth of Ehrlich's tumor in ascitic and solid form?
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Feitosa, Ivan Brito, Mori, Bruno, Teles, Carolina Bioni Garcia, and Costa, Alysson Guimarães da
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- 2021
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11. RISCOS COGNITIVOS DO USO PROLONGADO DE OMEPRAZOL: UMA PERSPECTIVA SOBRE DEMÊNCIA
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Marques, Emanuel Arislândio Costa, primary, Rocha, Izabella Gurgel do Amaral Pini, additional, Neves, Gelma Maria Jerônymo Vieira, additional, Gomes, Janine de Oliveira Alves, additional, Carvalho, Maria Vanda Nunes Santos, additional, Oliveira, Vivian Franciny Amaral, additional, and Feitosa, Ivan Brito, additional
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- 2024
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12. RELATIONSHIP BETWEEN 25(OH) D LEVELS AND DYSBIOSIS IN CHILDREN - SYSTEMATIC REVIEW
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Mori, Bruno, primary, Feitosa, Ivan Brito, additional, Lima, Luiz Eduardo Rodrigues, additional, Autran, Roseanne Gomes, additional, Souza, Celsa da Silva Moura, additional, and Barcellos, José Fernando Marques, additional
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- 2023
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13. Avaliação da vitalidade fetal e malformações associadas ao diabetes gestacional por ultrassonografia
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Barbosa, Emily de Oliveira Tourinho Gonçalves, primary, Barbosa, Kleber Gonçalves, additional, and Feitosa, Ivan Brito, additional
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- 2023
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14. Cardiopatias crônicas e o Covid-19: virulência, patogenia e interação medicamentosa / Chronic cardiopathies and Covid-19: virulence, pathogeny and drug interaction
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Thássia Christina de Souza Sena, Vinícius Santos Romão, Renata Maria Rocha, Giorgina Salazar Ibieta, André Luiz Ferreira Da Silva, and Ivan Brito Feitosa
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Marketing ,Pharmacology ,Organizational Behavior and Human Resource Management ,Strategy and Management ,Drug Discovery ,Pharmaceutical Science - Abstract
Introdução: Dentre as manifestações extrapulmonares da COVID-19 destacam-se os efeitos cardiovasculares, devido às complicações cardíacas, recentemente relatadas em pacientes com cardiopatias crônicas, associadas à alta carga inflamatória por SARS-CoV-2. Objetivos: Analisar as repercussões clínicas do COVID-19 em pacientes cardiopatas; investigar o processo fisiopatológico do COVID em cardiopatas, em comparação com o processo em pacientes não cardiopatas; avaliar o risco cardiovascular gerado por medicamentos usados contra o COVID-19, bem como efeitos de fármacos anti-hipertensivos na fisiopatologia do coronavírus. Material e Métodos: A pesquisa foi realizada em 3 bases de dados, incluindo MEDLINE / PubMed, Scopus, Web of science e ScienceDirect. A estratégia de busca utilizou os descritores obtidos no Medical Subject Headings (MESH) da National Library of Medicine com a combinação das palavras-chave COVID-19, cardiovascular diseases e coronavírus por meio dos operadores booleanos AND e OR. Resultados: Dezoito artigos se adequaram aos temas propostos para esta revisão. Destes, sete abordaram as manifestações clínicas do COVID-19 em cardiopatas, cinco mostraram a fisiopatologia da doença e outros seis descreveram interações medicamentosas. Os resultados apontam que a hipertensão arterial sistêmica está presente em 57% dos pacientes hospitalizados por COVID-19 em Nova York. Cerca de 10% dos pacientes com cardiopatias prévias desenvolvem miocardite, podendo evoluir para bloqueio de condução, taquiarritmias e comprometimento da função ventricular esquerda. Pacientes com COVID-19 que apresentam hipertensão ou cardiopatias têm risco 3-4 vezes maior de desenvolver doença grave. Não há dados que sustentam que os IECA/BRA2 facilitam a entrada do coronavírus por aumentar a expressão da ECA2. Portanto, os pacientes devem continuar com o tratamento prescrito. Conclusão: Observa-se, portanto, que os riscos para o desenvolvimento de COVID-19 estão fortemente associados, entre outros fatores, à presença de cardiopatia crônica. Além disso, o vírus pode causar lesões cardíacas pela associação com o receptor de ECA-2, o que requer monitoração dos marcadores de lesões miocárdicas para pacientes internados por Sars-CoV-2, especialmente cardiopatas.
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- 2022
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15. Atividade dos macrófagos nas doenças ateroscleróticas: um panorama geral / Macrophage activity in atherosclerotic diseases: overview
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Renata Maria Rocha, Thássia Christina de Souza Sena, Kamila Klegues Cidade Grabner, Manuela Estrela do Ó Lacerda, Victor Mota Maciel, and Ivan Brito Feitosa
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Marketing ,Pharmacology ,Organizational Behavior and Human Resource Management ,Strategy and Management ,Drug Discovery ,Pharmaceutical Science - Abstract
A aterosclerose é o maior problema de saúde pública no Brasil e no mundo, pois sua evolução está intimamente relacionada a diversos distúrbios cardiovasculares que levam a óbito, especialmente o infarto agudo do miocárdio (IAM) e o acidente vascular cerebral (AVC), que de forma progressiva, ocasionam diversas mortes no Brasil e no mundo a cada ano. Vale destacar que, para a formação das placas, a participação das células fagocitárias, especialmente os macrófagos, contribuem significativamente para a evolução e crescimento da aterosclerose nas adjacências dos endotélios.
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- 2022
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16. Estudos Avançados Interdisciplinares Volume 16
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Francisco Guilherme de Sousa Borges, Marla Bruniele Silva Bezerra, Susy Canuto de Oliveira Fenelon, Lara Beatriz Leal Deusdará Araújo, Daniela Oliveira Arêa Leão, Gustavo David da Silva Martins, Giovanna Louise Araújo Almeida Galvão, Weider Silva Pinheiro, Antonio Walberto Oliveira Gonçalves, Isaú Flávio Coutinho Pereira, Virginia Celia Maia Alencar Neta, Maria Fernanda Carvalho Arruda Lima, Brenda Guimarães Sipaúba Abreu, Ronaldo Cesar Lages Castelo Branco Filho, Dalvan Josué Fernandes da Silva, Débora Amanda Pedroza de Melo, Gabriela Vieira Araújo, João Pedro Liborio Neiva Eulálio, Christiny Carvalho Couto de Paula, Cláudio Quaresma Araújo Dourado Filho, Gabriela Alves Pereira, Diego Saimon de Souza Abrantes, Elcivan Bezerra Miranda, Fabiana Fagundes Barasuol, Fernando de Almeida Pereira, Thiago Christian da Silva, Ivan Brito Feitosa, and Jhonata Jankowitsch
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É com muita satisfação que apresentamos o décimo sexto volume da Coleção intitulada “ESTUDOS AVANÇADOS INTERDISCIPLINARES”, que reúne em seus capítulos pesquisadores de diversas instituições com discussões e temáticas que circundam uma gama de possibilidades de pesquisas e de relações dialógicas que certamente podem ser relevantes para o desenvolvimento social brasileiro a partir de uma ótica que contempla as mais vastas questões da sociedade. Tal obra visa dar publicidade a estudos e pesquisas frutos de árduos trabalhos acadêmicos que decerto contribuem, cada um a seu modo, para o aprofundamento de discussões em suas respectivas áreas pois são pesquisas germinadas, frutificadas e colhidas de temas atuais que estão sendo debatidos nas principais universidades nacionais e que refletem o interesse de pesquisadores no desenvolvimento social e científico que possam impactar positivamente a qualidade de vida de homens e de mulheres.
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- 2023
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17. UMA ANÁLISE SOBRE O ASTROVÍRUS
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Thiago Christian da Silva, Ivan Brito Feitosa, and Jhonata Jankowitsch
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- 2023
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18. Estudos Avançados Interdisciplinares Volume 16
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Borges, Francisco Guilherme de Sousa, primary, Bezerra, Marla Bruniele Silva, additional, Fenelon, Susy Canuto de Oliveira, additional, Araújo, Lara Beatriz Leal Deusdará, additional, Leão, Daniela Oliveira Arêa, additional, Martins, Gustavo David da Silva, additional, Galvão, Giovanna Louise Araújo Almeida, additional, Pinheiro, Weider Silva, additional, Gonçalves, Antonio Walberto Oliveira, additional, Pereira, Isaú Flávio Coutinho, additional, Neta, Virginia Celia Maia Alencar, additional, Lima, Maria Fernanda Carvalho Arruda, additional, Abreu, Brenda Guimarães Sipaúba, additional, Branco Filho, Ronaldo Cesar Lages Castelo, additional, Silva, Dalvan Josué Fernandes da, additional, Melo, Débora Amanda Pedroza de, additional, Araújo, Gabriela Vieira, additional, Eulálio, João Pedro Liborio Neiva, additional, Paula, Christiny Carvalho Couto de, additional, Dourado Filho, Cláudio Quaresma Araújo, additional, Pereira, Gabriela Alves, additional, Abrantes, Diego Saimon de Souza, additional, Miranda, Elcivan Bezerra, additional, Barasuol, Fabiana Fagundes, additional, Pereira, Fernando de Almeida, additional, Silva, Thiago Christian da, additional, Feitosa, Ivan Brito, additional, and Jankowitsch, Jhonata, additional
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- 2023
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19. Phonon structure, infra-red and raman spectra of Li2MnO3 by first-principles calculations
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Ruth Pulido, Nelson Naveas, Raúl J. Martin-Palma, Fernando Agulló-Rueda, Victor R. Ferró, Jacobo Hernández-Montelongo, Gonzalo Recio-Sánchez, Ivan Brito, Miguel Manso-Silván, UAM. Departamento de Física Aplicada, and UAM. Departamento de Ingeniería Química
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Crystals Structures ,Li2MnO3 ,DFT ,DFPT ,Raman spectroscopy ,IR spectroscopy ,Física ,General Materials Science ,Infra Red ,Phonon Structures ,Monoclinics ,Lithium Recoveries - Abstract
The layer-structured monoclinic Li2MnO3 is a key material, mainly due to its role in Li-ion batteries and as a precursor for adsorbent used in lithium recovery from aqueous solutions. In the present work, we used first-principles calculations based on density functional theory (DFT) to study the crystal structure, optical phonon frequencies, infra-red (IR), and Raman active modes and compared the results with experimental data. First, Li2MnO3 powder was synthesized by the hydrothermal method and successively characterized by XRD, TEM, FTIR, and Raman spectroscopy. Secondly, by using Local Density Approximation (LDA), we carried out a DFT study of the crystal structure and electronic properties of Li2MnO3. Finally, we calculated the vibrational properties using Density Functional Perturbation Theory (DFPT). Our results show that simulated IR and Raman spectra agree well with the observed phonon structure. Additionally, the IR and Raman theoretical spectra show similar features compared to the experimental ones. This research is useful in investigations involving the physicochemical characterization of Li2MnO3 material.
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- 2022
20. Sono e imunidade: papel do sistema imune, distúrbios do sono e terapêuticas / Sleep and immunity: role of the immune system, sleep disorders and treatment
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Thaís Pereira Santana, Jaine Alencar Muniz, Mirella Costa Lopes, Marcela Fernandes Lúcio, Anna Beatriz Barbosa Dos Santos, Diego Andrés Reyes Ahumada, Aline Cardoso Silva, Jully Anne Cavalcante Pereira, Lidiane Vitória Silva Soares, Maria luiza Guedes Da Silva, and Ivan Brito Feitosa
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Marketing ,Pharmacology ,Organizational Behavior and Human Resource Management ,Strategy and Management ,Drug Discovery ,Pharmaceutical Science - Published
- 2021
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21. O papel do intestino na homeostase imunológica / The role of the intestine in immunological homeostasis
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Ivan Brito Feitosa, Danilo Aureliano Almeida Geremia, Iasmine Pereira Barreto Tossatti, Fernanda Frohlich, Leila Fátima Schefer Meier, Marcos Rogério Inácio de Sene, Beremis Samir Pereira Barreto, and Julinês Bega Peixe
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Marketing ,Pharmacology ,Organizational Behavior and Human Resource Management ,Strategy and Management ,Drug Discovery ,Pharmaceutical Science ,Biology ,Molecular biology - Abstract
Atraves de um apanhado teorico, este trabalho tem o de objetivo de descrever a funcao do intestino no equilibrio das respostas imunologicas. Para isso o estudo, inicialmente apresenta as celulas que constituem o complexo do Trato Gastrointestinal (TGI), indicando em um quadro explicativo a funcao de cada uma destas de modo que sejam evidenciadas suas caracteristicas imunologicas. Nao obstante, o trabalho indica a formacao da microbiota intestinal, destacando seu perfil simbiotico para a saude do individuo, assim como pontua aspectos relevantes sobre sua manutencao pautada na dieta. De forma complementar, a pesquisa tambem aponta respostas imunes ao descrever os mecanismos acionados no TGI. Assim, se entendeu que o desempenho do sistema imune da mucosa associada ao intestino, em equilibrio, contribui para o controle de respostas exacerbadas a antigenos, usando como apoio a microbiota intestinal. Por fim, se estabelece que a disbiose no trato intestinal e um fator importante relacionado as patologias, sendo que o sistema imune ao ser ativado recorrera a mecanismo linfatico secundario para controlar os processos inflamatorios.
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- 2021
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22. The stochastic weighted viterbi algorithm: a frame work to compensate additive noise and low-bit rate coding distortion.
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Néstor Becerra Yoma, Ivan Brito, and Carlos Molina
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- 2004
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23. Feature-dependent compensation in speech recognition.
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Ivan Brito, Néstor Becerra Yoma, and Carlos Molina
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- 2004
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24. Language model accuracy and uncertainty in noise cancelling in the stochastic weighted viterbi algorithm.
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Néstor Becerra Yoma, Ivan Brito, and Jorge F. Silva
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- 2003
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25. Phonon Structure, Infra-Red and Raman Spectra of Li
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Ruth, Pulido, Nelson, Naveas, Raúl J, Martin-Palma, Fernando, Agulló-Rueda, Victor R, Ferró, Jacobo, Hernández-Montelongo, Gonzalo, Recio-Sánchez, Ivan, Brito, and Miguel, Manso-Silván
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The layer-structured monoclinic Li
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- 2022
26. ATIVIDADE DOS MACRÓFAGOS NAS DOENÇAS ATEROSCLERÓTICAS: UM PANORAMA GERAL
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Renata Maria Rocha, Thássia Christina de Souza Sena, Kamila Klegues Cidade Grabner, Manuela Estrela do Ó Lacerda, Victor Mota Maciel, and Ivan Brito Feitosa
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- 2022
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27. CESAREAN DELIVERY MODULATE INTESTINAL MICROBIOME AND TH9 CELL ASNWER PROPENSITY TO ALLERGIC DISEASES? / A MODULAÇÃO DO MICROBIOMA INTESTINAL POR INFLUÊNCIA DO PARTO CESARIANA POSSUI CORREÇÃO COM A RESPOSTA DAS CÉLULAS TH9 EM DOENÇAS ALÉRGICAS?
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Poliana Alves da Silva, Lara Graziela Fernandes Maia de Medeiros, Cleber Queiroz Leite, Jade Gomes da Costa Medeiros, Bruna Pechim Saldanha, Amanda Nascimento Vilas Boas, Nathalia Soave Tortora, Rafaela Calaça Marcelino, Ivan Brito Feitosa, and Julia Garcia Peres
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Marketing ,Pharmacology ,Organizational Behavior and Human Resource Management ,Strategy and Management ,Drug Discovery ,Pharmaceutical Science - Published
- 2021
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28. La influencia de la actividad física y los niveles de vitamina D e interleucina-10 sérica en niños y adolescentes. Protocolo de revisión sistemática
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Mori, Bruno, Mazalo, João Viriato, Feitosa, Ivan Brito, Lima , Luiz Eduardo Rodrigues, Autran, Roseanne Gomes, Souza, Celsa da Silva Moura, and Barcellos, José Fernando Marques
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Physical activity ,Vitamina D ,Adolescent ,Adolescente ,Criança ,Interleucina-10 ,Adolescentes ,Exercício físico ,Vitamin d ,Child ,Niños ,Ejercicio física ,Interleukin-10 - Abstract
Recent studies indicate a great relationship between the combination of physical activity, levels of vitamin D and interleukin-10, these factors are interpreted as indicators of health from children to adolescents. Therefore, the proposal of the protocol was to describe the aims and methods for a systematic review to summarize the studies by examining the influence of physical activity and vitamin D on serum levels of interleukin-10 in children and adolescents. A systematic review will be developed based on searches of articles in seven electronic databases and references of retrieved articles, contact with authors, and study repositories. Eligibility criteria: observational or experimental studies examining the Influence of Physical Activity and Vitamin D on Serum Levels of Interleukin-10 in Children and Adolescents (9 to 13y). Selection of the studies and extraction of the data will be carried out by two reviewers independently. Characteristics of the study, participants, methods of combinations, and main results will be extracted and described. Risk of bias and level of evidence in the studies will be assessed according to the Cochrane handbook The data will be synthesized using random effects meta-analysis for results that are homogeneous in terms of statistical, clinical, and methodological characteristics. If not, then a narrative synthesis will be conducted. The results of this review may provide insights to improve the current influence of physical activity and vitamin D on serum levels of interleukin-10 in children and adolescents, as well as a guide to future studies in this research field. Estudios recientes indican una gran relación entre la combinación de actividad física, niveles de vitamina D e interleucina-10, estos factores son interpretados como indicadores de salud en niños y adolescentes. Por lo tanto, el propósito de este protocolo es describir los objetivos y métodos de una revisión sistemática para resumir los estudios que examinaron la influencia de la actividad física y la vitamina D en los niveles séricos de interleucina -10 en niños y adolescentes. Se desarrollará una revisión sistemática basada en búsquedas de artículos en siete bases de datos electrónicas y referencias de artículos recuperados, contacto con autores y repositorios de estudios. Criterios de elegibilidad: estudios observacionales o experimentales que examinen la influencia de la actividad física y la vitamina D y los niveles séricos de interleucina -10 en niños y adolescentes (de 9 a 13 años). Dos revisores de forma independiente realizarán la selección de estudios y la extracción de datos. Se extraerán y describirán las características del estudio, los participantes, los métodos de combinación y los principales resultados. El riesgo de sesgo y el nivel de evidencia de los estudios se evaluarán según el manual Cochrane. Los datos se sintetizarán mediante metanálisis de efectos aleatorios para obtener resultados suficientemente homogéneos en cuanto a características estadísticas, clínicas y metodológicas. En caso contrario, se realizará una síntesis narrativa. Los resultados de esta revisión pueden proporcionar subsidios para mejorar la influencia actual de la actividad física y la vitamina D en los niveles séricos de interleucina-10 en niños y adolescentes, así como orientar futuros estudios en este campo de investigación. Estudos recentes indicam uma relação grandiosa entre a combinação de atividade física, os níveis de vitamina D e interleucina-10, esses fatores são interpretados como indicadores de saúde de crianças de adolescentes. Portanto, a proposta deste protocolo é descrever os objetivos e métodos para uma revisão sistemática para resumir os estudos que examinaram a influência da atividade física e da vitamina D nos níveis séricos de interleucina -10 em crianças e adolescentes. Uma revisão sistemática será desenvolvida com base em buscas de artigos em sete bases de dados eletrônicas e referências de artigos recuperados, contato com autores e repositórios de estudo. Critérios de elegibilidade: estudos observacionais ou experimentais que examinam a influência da atividade física e da vitamina D e os níveis séricos de interleucina -10 em crianças e adolescentes (9 a 13 anos). A seleção dos estudos e a extração dos dados serão realizadas por dois revisores de forma independente. Características do estudo, participantes, métodos de combinações e principais resultados serão extraídos e descritos. O risco de viés e o nível de evidência dos estudos serão avaliados de acordo com o manual Cochrane. Os dados serão sintetizados por meio de metanálise de efeitos aleatórios para resultados suficientemente homogêneos em termos de características estatísticas, clínicas e metodológicas. Caso contrário, será realizada uma síntese narrativa. Os resultados desta revisão podem fornecer subsídios para melhorar a atual influência da atividade física e da vitamina D nos níveis séricos de interleucina-10 em crianças e adolescentes, bem como orientar estudos futuros neste campo de pesquisa.
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- 2022
29. A influência da atividade física e vitamina D e níveis séricos de interleucina-10 em crianças e adolescentes. Protocolo de revisão sistemática
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Mori, Bruno, primary, Mazalo, João Viriato, additional, Feitosa, Ivan Brito, additional, Lima, Luiz Eduardo Rodrigues, additional, Autran, Roseanne Gomes, additional, Souza, Celsa da Silva Moura, additional, and Barcellos, José Fernando Marques, additional
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- 2022
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30. Cardiopatias crônicas e o Covid-19: virulência, patogenia e interação medicamentosa / Chronic cardiopathies and Covid-19: virulence, pathogeny and drug interaction
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Sena, Thássia Christina de Souza, primary, Romão, Vinícius Santos, additional, Rocha, Renata Maria, additional, Ibieta, Giorgina Salazar, additional, Da Silva, André Luiz Ferreira, additional, and Feitosa, Ivan Brito, additional
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- 2022
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31. Atividade dos macrófagos nas doenças ateroscleróticas: um panorama geral / Macrophage activity in atherosclerotic diseases: overview
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Rocha, Renata Maria, primary, Sena, Thássia Christina de Souza, additional, Grabner, Kamila Klegues Cidade, additional, Lacerda, Manuela Estrela do Ó, additional, Maciel, Victor Mota, additional, and Feitosa, Ivan Brito, additional
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- 2022
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32. Evaluation of the leishmanicidal and immunomodulator effect of furazolidone and its complex products with cyclodextrins on infection with Leishmania (L.) infantum
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Feitosa, Ivan Brito, 0000-0002-9056-199X, Costa, Allyson Guimar??es da, Teles, Carolina Bioni Garcia, Lopes, Ant??nio Luiz Ribeiro Boechat, Barcellos, Jos?? Fernando Marques, Mesquita, Elieth Afonso de, and Sadahiro, Aya
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Leishmaniose visceral ,Furazolidona ,CIENCIAS BIOLOGICAS ,Imunomodula????o ,Complexa????o com ciclodextrina ,Leishmaniose visceral - Tratamento - Abstract
Submitted by ivan feitosa (ivan.pvh.bio@gmail.com) on 2021-12-21T14:46:01Z No. of bitstreams: 4 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) TESE_Ivan Feitosa_PPGIBA.pdf: 1399656 bytes, checksum: 00d9a700f4cd83f31a4cb3a07b6129a3 (MD5) CartaEncaminhamentoTCC-TESE-DISSERTA????O_AGC.pdf: 109975 bytes, checksum: 89b0e0572acacd03853794624e22bb2f (MD5) Ivan.Ata de defesa.pdf: 56559 bytes, checksum: 4629d79aa5ca51247d5f8cb10a7d77a1 (MD5) Approved for entry into archive by PPGIBA Imunologia B??sica e Aplicada (ppgimunologia@ufam.edu.br) on 2021-12-31T15:30:19Z (GMT) No. of bitstreams: 4 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) TESE_Ivan Feitosa_PPGIBA.pdf: 1399656 bytes, checksum: 00d9a700f4cd83f31a4cb3a07b6129a3 (MD5) CartaEncaminhamentoTCC-TESE-DISSERTA????O_AGC.pdf: 109975 bytes, checksum: 89b0e0572acacd03853794624e22bb2f (MD5) Ivan.Ata de defesa.pdf: 56559 bytes, checksum: 4629d79aa5ca51247d5f8cb10a7d77a1 (MD5) Rejected by Divis??o de Documenta????o/BC Biblioteca Central (ddbc@ufam.edu.br), reason: Na ficha catalogr??fica foi duplicado parte do t??tulo como subt??tulo. O Campo "Subt??tulo" deve ficar em branco no formul??rio, uma vez que a Tese n??o tem subt??tulo. on 2022-01-03T18:39:36Z (GMT) Submitted by ivan feitosa (ivan.pvh.bio@gmail.com) on 2022-02-03T19:49:09Z No. of bitstreams: 4 CartaEncaminhamentoTCC-TESE-DISSERTA????O_AGC.pdf: 109975 bytes, checksum: 89b0e0572acacd03853794624e22bb2f (MD5) Ivan.Ata de defesa.pdf: 56559 bytes, checksum: 4629d79aa5ca51247d5f8cb10a7d77a1 (MD5) Tese_PPGIBA_DEPOSITO_IVAN FEITOSA.pdf: 1399898 bytes, checksum: b2986dae871c865c133aa6f2ada793be (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Approved for entry into archive by PPGIBA Imunologia B??sica e Aplicada (ppgimunologia@ufam.edu.br) on 2022-02-03T20:13:40Z (GMT) No. of bitstreams: 4 CartaEncaminhamentoTCC-TESE-DISSERTA????O_AGC.pdf: 109975 bytes, checksum: 89b0e0572acacd03853794624e22bb2f (MD5) Ivan.Ata de defesa.pdf: 56559 bytes, checksum: 4629d79aa5ca51247d5f8cb10a7d77a1 (MD5) Tese_PPGIBA_DEPOSITO_IVAN FEITOSA.pdf: 1399898 bytes, checksum: b2986dae871c865c133aa6f2ada793be (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Approved for entry into archive by Divis??o de Documenta????o/BC Biblioteca Central (ddbc@ufam.edu.br) on 2022-02-03T20:28:42Z (GMT) No. of bitstreams: 4 CartaEncaminhamentoTCC-TESE-DISSERTA????O_AGC.pdf: 109975 bytes, checksum: 89b0e0572acacd03853794624e22bb2f (MD5) Ivan.Ata de defesa.pdf: 56559 bytes, checksum: 4629d79aa5ca51247d5f8cb10a7d77a1 (MD5) Tese_PPGIBA_DEPOSITO_IVAN FEITOSA.pdf: 1399898 bytes, checksum: b2986dae871c865c133aa6f2ada793be (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Made available in DSpace on 2022-02-03T20:28:42Z (GMT). No. of bitstreams: 4 CartaEncaminhamentoTCC-TESE-DISSERTA????O_AGC.pdf: 109975 bytes, checksum: 89b0e0572acacd03853794624e22bb2f (MD5) Ivan.Ata de defesa.pdf: 56559 bytes, checksum: 4629d79aa5ca51247d5f8cb10a7d77a1 (MD5) Tese_PPGIBA_DEPOSITO_IVAN FEITOSA.pdf: 1399898 bytes, checksum: b2986dae871c865c133aa6f2ada793be (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2021-11-22 CAPES - Coordena????o de Aperfei??oamento de Pessoal de N??vel Superior Visceral leishmaniasis (VL) is a systemic disease caused by protozoa of the genus Leishmania and transmitted by sandflies. Early diagnosis and treatment remain the main mechanisms of VL control, however, the available pharmacotherapy is still limited and the search for new treatments for VL remains a worldwide medical emergency. Thus, the objective of this work is to evaluate in vitro the cytotoxic, leishmanicidal and immunomodulatory activity in macrophages (M1 and M2) of furazolidone (FZD) and its complexation products with cyclodextrin (FZD-CD) at different concentration ratios on the Leishmania (L.) infantum infection. Initially, a systematic review was carried out, following the PICO strategy (Problem, Intervention, Comparison and Outcome), in order to establish which immune mechanisms are described on the effects of FZD administration. Then, in vitro activity assays were performed: cytotoxicity test (J774 murine macrophage lineage cells), 50% growth inhibition of promastigote forms (IC50), 50% growth inhibition of amastigote forms (ICA50) of Leishmania (L.) infantum, selectivity index estimation, phagocytosis analysis by zymosan count, dosage of reactive oxygen species and nitric oxide, in addition to the immunophenotyping of M1 and M2 macrophages. As a result of the systematic review, 943 papers were found, 605 were selected after removal of duplication, 35 remained for eligibility and of these, 4 answered the guiding question and were included. The studies included indicated that the administration of FZD can induce pro- or anti-inflammatory pathways, with the likely increase in the expression of reactive oxygen species and modulation of apoptotic pathways. Experimental tests revealed that of the 12 complexation products, the physical mixture of FZD with ??-cyclodextrin in the proportion 1:2 and the physical mixture of FZD with hydroxypropyl-??-cyclodextrin in the proportion 1:1 had leishmanicidal effects in the promastigote and amastigote forms and with lower cytotoxicity (Selectivity Index [IS] values of 13.8 and 499.37 ??g/mL, respectively; considering leishmanicidal data against amastigotes) when compared to furazolidone (IS value of 2.52 ??g/mL). Only free FZD at a concentration of 0.3 ??g/mL increased the rate of phagocytosis and at a concentration of 3 ??g/mL it stimulated NO production. The physical mixture of FZD with hydroxypropyl-??-cyclodextrin in a 1:1 ratio induced the formation of reactive oxygen species at a concentration of 3 ??g/mL. Finally, FZD and MFHFZD 1:1 did not show a significant increase in the percentage of macrophages polarized in M1 and M2, and our hypothesis was partially tested, where the complexation of furazolidone with cyclodextrins originated non-complex complexes and aggregates with leishmanicidal effect, with low toxicity, stimulating phagocytosis and production of reactive oxygen and nitric oxide species, but not leading to macrophage polarization in the M1 profile in an in vitro model of infection by Leishmania (L.) infantum. A leishmaniose visceral (LV) ?? uma doen??a sist??mica causada por protozo??rios do g??nero Leishmania e transmitida por flebotom??neos. O diagn??stico e o tratamento precoce continuam sendo os principais mecanismos de controle da LV, entretanto, a farmacoterapia dispon??vel ainda ?? limitada e a busca de novos tratamentos para LV continua sendo uma emerg??ncia m??dica mundial. Desta forma, o objetivo deste trabalho consiste em avaliar in vitro a atividade citot??xica, leishmanicida e imunomoduladora em macr??fagos (M1 e M2) da furazolidona (FZD) e seus produtos de complexa????o com ciclodextrina (FZD-CD) em diferentes propor????es de concentra????o sobre a infec????o de Leishmania (L.) infantum. Inicialmente foi realizada uma revis??o sistem??tica, seguindo a estrat??gia PICO (Problema, Interven????o, Compara????o e Desfecho), com intuito de estabelecer quais os mecanismos imunes est??o descritos sobre os efeitos da administra????o da FZD. Em seguida, foram realizados ensaios de atividade in vitro: teste de citotoxicidade (c??lulas de linhagem de macr??fagos murinos J774), inibi????o de crescimento de 50% de formas promastigotas (IC50), inibi????o de crescimento de 50% de formas amastigotas (ICA50) de Leishmania (L.) infantum, estimativa do ??ndice de seletividade (IS), an??lise de fagocitose por contagem de zimosan, dosagem de esp??cies reativas de oxig??nio (EROS) e oxido n??trico (NO), al??m da imunofenotipagem de macr??fagos M1 e M2. Como resultado da revis??o sistem??tica foram encontrados 943 trabalhos, sendo 605 selecionados ap??s remo????o de duplica????o, 35 mantiveram-se para elegibilidade e destes, 4 responderam a pergunta norteadora e foram inclu??dos. Os trabalhos inclusos indicaram que a administra????o de FZD pode induzir vias pr?? ou anti-inflamat??rias, com o prov??vel aumento da express??o de EROS e modula????o de vias apopt??ticas. Os ensaios experimentais revelaram que dos 12 produtos de complexa????o, a mistura f??sica de FZD com ??-ciclodextrina na propor????o 1:2 e a mistura f??sica de FZD com hidroxipropril-??-ciclodextrina (MFHFZD) na propor????o 1:1 apresentaram efeitos leishmanicidas nas formas promastigotas, amastigotas e com menor citotoxicidade (valores de IS de 13,8 e 499,37 ??g/mL, respectivamente; considerando os dados leishmanicidas contra amastigotas) quando comparada a furazolidona (valor de IS de 2,52 ??g/mL). Somente A FZD livre na concentra????o de 0,3 ??g/mL aumentou a taxa de fagocitose e na concentra????o de 3 ??g/mL estimulou a produ????o de NO. A mistura f??sica de FZD com hidroxipropril-??-ciclodextrina na propor????o 1:1 induziu a forma????o de EROS na concentra????o de 3 ??g/mL. Por fim, A FZD e MFHFZD 1:1 n??o apresentaram aumento significativo na porcentagem de macr??fagos polarizados em M1 e M2 in vitro, sendo nossa hip??tese parcialmente testada, onde a complexa????o da furazolidona com as ciclodextrinas originou complexos e agregados do tipo n??o-complexos com efeito leishmanicida, com baixa toxicidade, estimulando a fagocitose e a produ????o de EROS e NO, por??m, n??o levando a polariza????o de macr??fagos no perfil M1 em modelo in vitro de infec????o por Leishmania (L.) infantum.
- Published
- 2021
33. What are the immunopharmacological effects of furazolidone? A systematic review
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Feitosa, Ivan Brito, primary, Mori, Bruno, additional, Santos, Ana Paula de Azevedo dos, additional, Villanova, Janaína Cecília Oliveira, additional, Teles, Carolina Bioni Garcia, additional, and Costa, Allyson Guimarães, additional
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- 2021
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34. Heterobimetallic Three-Dimensional 4 d-4 f Coordination Polymers Based on 5-methyl-1-(pyridyn-4-ylmethyl)-1 H-1,2,3-triazole-3,4-dicarboxylate
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Pilar Narea, Benjamin Hernández, Jonathan Cisterna, Alejandro Cárdenas, Jaime Llanos, Pilar Amo-Ochoa, Felix Zamora, José Luis Priego, Miguel Cortijo, Gerzon E. Delgado, and Ivan Brito
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History ,Polymers and Plastics ,Business and International Management ,Industrial and Manufacturing Engineering - Published
- 2021
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35. Sono e imunidade: papel do sistema imune, distúrbios do sono e terapêuticas / Sleep and immunity: role of the immune system, sleep disorders and treatment
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Santana, Thaís Pereira, primary, Muniz, Jaine Alencar, additional, Lopes, Mirella Costa, additional, Lúcio, Marcela Fernandes, additional, Dos Santos, Anna Beatriz Barbosa, additional, Ahumada, Diego Andrés Reyes, additional, Silva, Aline Cardoso, additional, Pereira, Jully Anne Cavalcante, additional, Soares, Lidiane Vitória Silva, additional, Da Silva, Maria luiza Guedes, additional, and Feitosa, Ivan Brito, additional
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- 2021
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36. O papel do intestino na homeostase imunológica / The role of the intestine in immunological homeostasis
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Geremia, Danilo Aureliano Almeida, primary, Peixe, Julinês Bega, additional, Barreto, Beremis Samir Pereira, additional, Frohlich, Fernanda, additional, Tossatti, Iasmine Pereira Barreto, additional, De Sene, Marcos Rogério Inácio, additional, Meier, Leila Fátima Schefer, additional, and Feitosa, Ivan Brito, additional
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- 2021
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37. Structure and Properties of (CH
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Rodrigo, Castillo, Jonathan, Cisterna, Ivan, Brito, Sergio, Conejeros, and Jaime, Llanos
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The new compound (CH
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- 2020
38. CESAREAN DELIVERY MODULATE INTESTINAL MICROBIOME AND TH9 CELL ASNWER PROPENSITY TO ALLERGIC DISEASES? / A MODULAÇÃO DO MICROBIOMA INTESTINAL POR INFLUÊNCIA DO PARTO CESARIANA POSSUI CORREÇÃO COM A RESPOSTA DAS CÉLULAS TH9 EM DOENÇAS ALÉRGICAS?
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Feitosa, Ivan Brito, primary, Leite, Cleber Queiroz, additional, Medeiros, Jade Gomes da Costa, additional, Medeiros, Lara Graziela Fernandes Maiade, additional, Boas, Amanda Nascimento Vilas, additional, Saldanha, Bruna Pechim, additional, Peres, Julia Garcia, additional, Marcelino, Rafaela Calaça, additional, Silva, Poliana Alves da, additional, and Tortora, Nathália Soave, additional
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- 2021
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39. Immunomodulating effects of Phlebotomine saliva in Leishmania infection: Review
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Feitosa, Ivan Brito, primary, Aguida, Wesley Roberto de, additional, and Teles, Carolina Bioni Garcia, additional
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- 2018
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40. Additional Insights into the Obtusallene Family: Components of Laurencia marilzae
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María L. Souto, Matías López-Rodríguez, Christian D. Muller, Ivan Brito, Adrián Gutiérrez-Cepeda, José J. Fernández, Manuel Norte, Institut Pluridisciplinaire Hubert Curien (IPHC), Université de Strasbourg (UNISTRA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), École Polytechnique de Montréal (EPM), University of Évora [Portugal], Cooltech Applications, and Cooltech
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Carcinoma, Hepatocellular ,Acetogenins ,Stereochemistry ,Molecular Conformation ,Pharmaceutical Science ,Antineoplastic Agents ,Apoptosis ,[SDV.CAN]Life Sciences [q-bio]/Cancer ,Crystallography, X-Ray ,010402 general chemistry ,Laurencia ,01 natural sciences ,Molecular conformation ,Analytical Chemistry ,chemistry.chemical_compound ,Ethers, Cyclic ,Drug Discovery ,Humans ,Carboxylate ,ComputingMilieux_MISCELLANEOUS ,Pharmacology ,Molecular Structure ,biology ,010405 organic chemistry ,Laurencia marilzae ,Organic Chemistry ,[SDV.MHEP.HEG]Life Sciences [q-bio]/Human health and pathology/Hépatology and Gastroenterology ,biology.organism_classification ,Hydrocarbons, Brominated ,3. Good health ,0104 chemical sciences ,Complementary and alternative medicine ,chemistry ,Spain ,Obtusallene ,[SDV.SP.PHARMA]Life Sciences [q-bio]/Pharmaceutical sciences/Pharmacology ,Molecular Medicine ,Derivative (chemistry) - Abstract
The obtusallenes are a significant subset of C15-halogenated acetogenins that incorporate 12-membered cyclic ethers. We have recently reported the isolation from Laurencia marilzae of 12-epoxyobtusallene IV (1) and its related α,β-unsaturated carboxylate ester (2), both of special biogenetic relevance. Here we describe the final step of our study, the isolation of three new analogues (3-5), among these, the first bromopropargylic derivative (3) of this class of macrocyclic C15-acetogenins. The structures were elucidated by analysis of NMR and X-ray data. 12-Epoxyobtusallene IV (1), its new isomer 4, and known obtusallene IV (6) were evaluated for their apoptosis-inducing activities in a human hepatocarcinoma cell line.
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- 2016
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41. Microalgas de dois ambientes lóticos amazônicos, Rondônia, BrasilMicroalgae of two lotic amazonian environments, Rondônia, Brasil
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Feitosa, Ivan Brito, Moura, Ariadne do Nascimento, de Souza, Ana Cristina Ramos, and CNPq
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Biologia ,limnologia ,Fitoplâncton, Ambientes lóticos, Norte do Brasil - Abstract
O objetivo deste trabalho foi identificar microalgas de dois ambientes lóticos amazônicos, localizados nas bacias dos rios Purus e Madeira, em Porto Velho, Rondônia, Brasil. As coletas foram realizadas nos meses de setembro e novembro de 2009 (águas baixas) e de fevereiro e abril de 2010 (águas altas), nas subacias dos rios Açuã e Aponiã. As amostras foram coletadas através de arrastos verticais e horizontais na área marginal dos rios com rede de plâncton de 25mm de abertura de malha e preservadas em solução de Transeau. Simultaneamente, foram coletadas amostras para medições de pH, turbidez e condutividade elétrica. Em laboratório, foram confeccionadas lâminas e observadas em microscópio e a identificação das espécies através de literatura especializada. O período de águas baixas caracterizou-se, em geral, por pH de levemente ácido a neutro, se comparado ao período de águas altas em ambos os rios. Já a turbidez e condutividade elétrica foram menores nas águas altas em ambos os rios e, no rio Aponiã, nas águas baixas. Foram identificados 79 táxons distribuídos em cinco divisões taxonômicas, sete classes, 15 ordens e 25 famílias. Nove espécies ocorreram somente no período de estiagem e 25 espécies apenas no período chuvoso. As espécies com maior frequência de ocorrência foram Oscillatoria principes, Desmidium grevillei, Actinella sp., Bambusina brebisonii, Micrasterias rotata, Eunotia sp., Cladophora sp. e Spirogyra sp. Dos 79 táxons, 61 espécies são citadas pela primeira vez para o estado de Rondônia.AbstractThe aim of this study was to identify the microalgae of two lotic Amazonian environments, situated in the watershed of Purus and Madeira rivers, in Porto Velho, Rondonia, Brazil. The sampling was performed in September and November of 2009 (low water) and February and April of 2010 (high water) in the sub-water basins of Acua and Aponiã rivers. The samples were collected by vertical and horizontal hauls in the marginal area of the rivers with a 25 μm nylon plankton net and preserved in Transeau solution. Simultaneously it was collected samples for pH, turbidity and conductivity. In laboratory, slides were prepared and observed under a microscope and species were identified based on specialized literature. The study revealed that the low water period was characterized generally by pH slightly acid to neutral, as well as turbidity and lower electrical conductivity as compared to the period of high water levels in both rivers. It was identified 79 taxa in five taxonomic divisions, seven classes, 15 orders and 25 families. Nine species occurred only in the dry period and only 25 species in the rainy period. The species with the highest frequency of occurrence were Oscillatoria principes, Desmidium grevillei, Actinella sp., Bambusina brebisonii, Micrasterias rotata, Eunotia sp., Cladophora sp. e Spirogyra sp. Of the 79 taxa, 61 species are first cited for the state of Rondônia.
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- 2015
42. Withanolides from three species of the genus Deprea (Solanaceae). Chemotaxonomical considerations
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Clara Inés Orozco, Gloria Estela Barboza, Viviana E. Nicotra, Alejandro Cárdenas, Juan C. Oberti, Ivan Brito, and Carina Noelia Casero
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Molecular Conformation ,Plant Science ,Colombia ,Horticulture ,Biology ,Crystallography, X-Ray ,Tribe (biology) ,Biochemistry ,CHEMATAXONOMIC MARKERS ,WITHANOLIDES ,Genus ,Botany ,SOLANACEAE ,Nuclear Magnetic Resonance, Biomolecular ,Withanolides ,Molecular Biology ,Solanaceae ,Molecular Structure ,Otras Ciencias Químicas ,Ciencias Químicas ,General Medicine ,Plant Components, Aerial ,WITHANOLIDOS ,Deprea bitteriana ,biology.organism_classification ,Química Orgánica ,DEPREA ,CIENCIAS NATURALES Y EXACTAS - Abstract
Nine withanolides were isolated from the aerial parts of Deprea bitteriana, Deprea cuyacensis, and Depreazamorae. D. bitteriana yielded two withaphysalins, D. cuyacensis gave two 13,14-seco withaphysalins,while D. zamorae yielded five physangulidines. The compounds were fully characterized by a combinationof spectroscopic methods (1D and 2D NMR and MS). All compounds isolated from D. bitterianaand D. cuyacensis were obtained as epimeric mixtures at C-18. The structure of physangulidine D wasconfirmed by X-ray diffraction analysis. The skeletons found in this research support the chemotaxonomicalposition of the genus Deprea in the tribe Physalideae. Fil: Casero, Carina Noelia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Oberti, Juan Carlos María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Orozco, Clara Inés. Universidad Nacional de Colombia; Colombia Fil: Cárdenas, Alejandro. Universidad de la Laguna; España Fil: Brito, Iván. Universidad de la Laguna; España Fil: Barboza, Gloria Estela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Nicotra, Viviana Estela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina
- Published
- 2015
43. Microalgae of two lotic amazonian environments, Rondônia, Brasil
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Ariadne do Nascimento Moura, Ana Cristina Ramos de Souza, and Ivan Brito Feitosa
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River ecosystem ,Geography ,Ecology ,Amazonian - Published
- 2015
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44. Dimer complexes of 2,4-toluenediamine-N,N,N′,N′-tetraacetic acid (2,4-TDTA) with copper(II), nickel(II), cobalt(II), zinc(II) and manganese(II). Studies in aqueous solution and solid state. X-ray crystal structures of Na4[Ni2(2,4-TDTA)2]·15H2O and Na4[Cu2(2,4-TDTA)2]·20H2O
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Matías L. Rodríguez, Felipe Brito, Sixto Domínguez, Francesc Lloret, Argelio Rancel, Xavier Solans, Alfredo Mederos, Antonio E. Rivero, Pedro Gili, Ivan Brito, and Catalina Ruiz-Pérez
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Ligand ,Dimer ,chemistry.chemical_element ,Crystal structure ,Zinc ,Inorganic Chemistry ,Nickel ,Bipyramid ,chemistry.chemical_compound ,Crystallography ,Octahedron ,chemistry ,Stability constants of complexes ,Materials Chemistry ,Physical and Theoretical Chemistry - Abstract
Potentiometric investigations in aqueous solution at 25°C and ionic strength 0.1 mol dm−3 KCl show that 2 2,4-toluenediamine-N,N,N′N′-tetraacetic acid (2,4-TDTA) forms with Cu(II), Ni(II), Co(II), Zn(II) and Mn(II) the following complexes (ligand, H4L): monomers [MH2L], [MHL]− and [ML]2−; dimers [M2HL2]3− and [M2L2]4−; with excess of ligand [MH2L2]4−, [MHL2]5− and [ML2]6− (Cu(II), Ni(II) and Zn(II)) and with excess of metal [M2HL]+ (Ni(II), Co(II)and Mn(II) and [M2L] (Cu(II)). The formation constants of the complexes have been determined. The species distribution diagrams indicate that a concentrated solution with a ligand:metal ratio 1:1 at pH 6 is suitable for the synthesis of crystalline salts of the dimetric complex species of Cu(II), Ni(II), Co(II), Zn(II) and Mn(II). X-ray diffraction structural analysis of the complexes Na4[Ni2(2,4-TDTA)2] · 15H2O and Na4[Cu2(2,4-TDTA)2]· 20H2O revealed that the dimer complex of Ni(II) is C1 and the dimer complex of Cu(II) is centrosymmetrical (C1). In both complexes each metal atom is surrounded by four carboxylic oxygens and two amine nitrogens in a distorted octahedron, for the Ni(II) complex, and an elongated bipyramid for the Cu(II) complex. X-ray diffraction analysis in powder was carried out for the complex Na4[Co2(2,4-TDTA)2] · 12H2O. The electronic properties have been characterised by spectroscopic techniques and variable-temperature magnetic susceptibility measurements. An orbital interpretation of the pathway of exchange interaction in this series of dimeric complexes is presented. The complexes were also characterised by mass and IR spectra and thermogravimetric analysis.
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- 1997
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45. Metal Recovery from Natural Saline Brines with an Electrochemical Ion Pumping Method Using Hexacyanoferrate Materials as Electrodes
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Sebastian Salazar-Avalos, Alvaro Soliz, Luis Cáceres, Sergio Conejeros, Iván Brito, Edelmira Galvez, and Felipe M. Galleguillos Madrid
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metal recovery ,mixing entropy battery ,Prussian Blue analogue ,electrochemical ion pumping ,nanomaterials ,Chemistry ,QD1-999 - Abstract
The electrochemical ion pumping device is a promising alternative for the development of the industry of recovering metals from natural sources—such as seawater, geothermal water, well brine, or reverse osmosis brine—using electrochemical systems, which is considered a non-evaporative process. This technology is potentially used for metals like Li, Cu, Ca, Mg, Na, K, Sr, and others that are mostly obtained from natural brine sources through a combination of pumping, solar evaporation, and solvent extraction steps. As the future demand for metals for the electronic industry increases, new forms of marine mining processing alternatives are being implemented. Unfortunately, both land and marine mining, such as off-shore and deep sea types, have great potential for severe environmental disruption. In this context, a green alternative is the mixing entropy battery, which is a promising technique whereby the ions are captured from a saline natural source and released into a recovery solution with low ionic force using intercalation materials such as Prussian Blue Analogue (PBA) to store cations inside its crystal structure. This new technique, called “electrochemical ion pumping”, has been proposed for water desalination, lithium concentration, and blue energy recovery using the difference in salt concentration. The raw material for this technology is a saline solution containing ions of interest, such as seawater, natural brines, or industrial waste. In particular, six main ions of interest—Na+, K+, Mg2+, Ca2+, Cl−, and SO42−—are found in seawater, and they constitute 99.5% of the world’s total dissolved salts. This manuscript provides relevant information about this new non-evaporative process for recovering metals from aqueous salty solutions using hexacianometals such as CuHCF, NiHCF, and CoHCF as electrodes, among others, for selective ion removal.
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- 2023
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46. ChemInform Abstract: Structure of Dihydrodecompostin
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René Torres, Matías L. Rodríguez, Luis Villarroel, and Ivan Brito
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Chemical physics ,Chemistry ,Structure (category theory) ,General Medicine - Published
- 2010
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47. ChemInform Abstract: New Examples of Acyclic and Cyclic C-15 Acetogenins from Laurencia pinnatifida. Reassignment of the Absolute Configuration for E and Z Pinnatifidienyne
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Antonio G. González, M. Norte, F. Cataldo, Ivan Brito, and M. L. Rodriguez
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Stereochemistry ,Chemistry ,Absolute configuration ,General Medicine ,Laurencia pinnatifida - Published
- 2010
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48. Structures of (N,N-dicyclohexyl)benzenesulfenamide and its pentacarbonylchromium(0) complex via the sulfur atom
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Guillermo González, Carlos Díaz, Matías L. Rodríguez, Ivan Brito, and Victor Manriquez
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chemistry.chemical_classification ,Denticity ,Organic Chemistry ,Inorganic chemistry ,Sulfenamide ,chemistry.chemical_element ,Crystal structure ,Biochemistry ,Sulfur ,Inorganic Chemistry ,chemistry.chemical_compound ,Crystallography ,chemistry ,X-ray crystallography ,Materials Chemistry ,Molecule ,Physical and Theoretical Chemistry ,Inorganic compound - Published
- 1992
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49. New examples of acyclic and cyclic C-15 acetogenins from laurencia pinnatifida. Reassignment of the absolute configuration for E and Z pinnatifidienyne
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Fernando Cataldo, Ivan Brito, Matías L. Rodríguez, Antonio G. González, and Manuel Noite
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Chemistry ,Stereochemistry ,Organic Chemistry ,Drug Discovery ,Absolute configuration ,Haloalcohol ,Laurencia pinnatifida ,Biochemistry - Abstract
Seven new C-15 acetogenins have been isolated from Laurencia pinnatifida , their structures being established by spectroscopic methods and chemical correlations. The absolute configuration of E and Z pinnatifidienyne have been reassigned on the basis of X-ray analysis.
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- 1991
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50. Diterpenoids from Calceolaria thyrsiflora
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M.L. Rodríguez, Marisa Piovano, Vicente Gambaro, Catalina Ruiz-Pérez, Carlos Henríquez Miranda, Ivan Brito, María C. Chamy, and Juan A. Garbarino
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Chemical transformation ,Scrophulariaceae ,Stereochemistry ,Plant Science ,General Medicine ,Horticulture ,Biology ,biology.organism_classification ,Biochemistry ,chemistry.chemical_compound ,Thyrsiflorin B ,chemistry ,Calceolaria thyrsiflora ,Diterpene ,Molecular Biology - Abstract
Three novel diterpenes, thyrsiflorin A, thyrsiflorin B, thyrsiflorin C, and the dehidroabietane derivatives, abietatrien-3β-ol and 3β-acetoxy abietatrien were isolated from the aerial parts of Calceolaria thyrsiflora . The structures of the new compounds were elucidated by spectroscopic methods, chemical transformation and X-ray analysis.
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- 1991
- Full Text
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