6 results on '"BARROS, Carlos Jonnatan Pimentel"'
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2. Metabonômica baseada em RMN como ferramenta para discriminação de grãos de soja irradiados & diagnóstico de hepatites e fibrose hepática
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BARROS, Carlos Jonnatan Pimentel, SILVA, Ricardo Oliveira da, and LOPES NETO, Edmundo Pessoa de Almeida
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Quimiometria ,Hepatite viral ,Química analítica - Abstract
CNPq Neste trabalho, foram construídos modelos metabonômicos baseados na espectroscopia de ressonância magnética nuclear de hidrogênio (RMN de ¹H) e no emprego de técnicas de análise estatística multivariada para: discriminação entre grãos de soja expostos à radiação gama, com fins fitossanitários, e aqueles não irradiados; investigar e diferenciar portadores de hepatites virais (do tipo B ou C) de voluntários saudáveis; e classificar pacientes com hepatite C crônica, em função do grau de fibrose hepática. Para o trabalho usando grãos de soja, os extratos clorofórmicos dos mesmos foram analisados por RMN de ¹H e os modelos PCA e PLS-DA evidenciaram separação entre os grupos de amostras irradiadas e não irradiadas. Na validação cruzada total, o modelo PLS-DA apresentou uma exatidão de 100%, R² de 0,973 e Q² de 0,958. As variáveis discriminatórias mais importantes foram δ 1,57 e 1,62 ppm, que estão relacionadas aos grupos metilênicos β-carboxila de ésteres e dos ácidos carboxílicos livres, respectivamente. Nos estudos de casos de hepatites, foram analisados por RMN de ¹H amostras de soro e urina de pacientes portadores de hepatite B ou C e de voluntários saudáveis. Os modelos usando PCA ou PLS-DA construídos com o intuito de discriminar os três grupos analisados não apresentaram distinção entre os grupos. No entanto, para a discriminação entre o grupo dos pacientes com hepatites (B ou C) e o grupo controle, foram observadas tendências de separação nos modelos de PCA e PLS-DA, utilizando-se soro ou urina. Os melhores resultados foram obtidos usando amostras de soro. Na validação cruzada total, para o melhor modelo usando o formalismo PLS-DA apresentou exatidão de 80,2%, R² de 0,365 e Q² de 0,192. O formalismo LDA também foi utilizado e o modelo com as amostras de soro apresentou os melhores resultados, com sensibilidade de 92,3%, especificidade de 69,2%, valor preditivo positivo de 88,2% e valor preditivo negativo de 78,3%. Por fim, foram analisadas amostras de soro de pacientes com hepatite C crônica e diagnóstico de grau de fibrose, provenientes de dois grupos: amostras coletadas em Recife/PE e no Rio de Janeiro/RJ. Os modelos metabonômicos foram criados de forma a discriminar os diferentes graus de fibrose: fibrose avançada (F3 e F4) x fibrose não-avançada (F0, F1 e F2); fibrose significativa (F2, F3 e F4) x fibrose não-significativa (F0 e F1). Para as amostras de Recife/PE, usando o formalismo LDA, foram encontrados valores de exatidão maiores que 95%, em todos os modelos, utilizando validação cruzada. Amostras pertencentes ao grupo de fibrose intermediária (F2) foram encontradas a partir dos dois modelos anteriores com sensibilidade de 100%. As análises por PLS-DA também mostraram clara separação entre os grupos, e foram validadas por validação cruzada e teste de permutação. Para as amostras do Rio de Janeiro/RJ, as análises por LDA e PLS-DA mostraram resultados semelhantes. Os modelos construídos mostraram que a estratégia metabonômica pode ser empregada em diferentes segmentos, como agroindústria e medicina, com eficiências semelhantes. In this work, we built metabonomics models based on proton nuclear magnetic resonance (¹H NMR) and for multivariate statistical analysis. These models were used to discriminate among gamma irradiated and non-irradiated soybean samples for phytosanitary purposes; for research and discriminate of viral hepatitis patients (type B or C) from healthy volunteers; and to classify the degree of liver fibrosis in hepatitis C patients. For the study with soybeans, chloroform extracts of the grains were analyzed by ¹H NMR and metabonomics models with PCA and PLS-DA showed separation between the irradiated samples and non-irradiated ones. In the leave one out cross validation (LOOCV), the PLS-DA model showed an accuracy of 100%, R² of 0.973 and Q² of 0.958. The most important discriminatory variables were δ 1,57 and 1,62 ppm, which are related to ester β -carboxyl methylene groups and carboxylic acids β -carboxyl methylene groups, respectively. In the viral hepatitis study, serum and urine from patients with B or C hepatitis and from healthy volunteers were analyzed by ¹H NMR. None of the PCA and PLS-DA models were able to discriminate among the three groups. On the other hand, discrimination between hepatitis (B or C) patients and the control group was more effective, with separation trends in the models using PCA and PLS-DA, with serum and urine. The serum models showed the best results. In the LOOCV, PLS-DA model was accurate to 80.2%, R² of 0.365% and Q² of 0.192. The LDA formalism was also used with the serum models showed the best results, with a sensibility of 92.3%, specificity of 69.2%, predictive positive value of 88.2% and predictive negative value of 78.3%. Finally, serum samples from patients with chronic hepatitis C and fibrosis stage diagnosis were analyzed, from two groups: samples collected in Recife/PE and in Rio de Janeiro/RJ. Metabonomic models were created to differentiate among the different degrees of fibrosis: advanced fibrosis (F3 and F4) x non-advanced fibrosis (F0, F1 and F2); significant fibrosis (F2, F3 and F4) x non-significant fibrosis (F0 and F1). The Recife/PE LDA models showed more than 95% accuracy for LOOCV. Samples with intermediate fibroses (F2) were found with sensibility of 100%. PLS-DA models also clearly discriminated among the groups, validated with LOOCV and permutation tests models. The LDA and PLS-DA models for the Rio de Janeiro/RJ samples had similar results. The metabonomics models demonstrate that this strategy can be used in different areas, such as agribusiness and medicine, with similar efficiency.
- Published
- 2017
3. Proton nuclear magnetic resonance-based metabonomic models for non-invasive diagnosis of liver fibrosis in chronic hepatitis C: Optimizing the classification of intermediate fibrosis
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Batista, Andrea Dória, primary, Barros, Carlos Jonnatan Pimentel, additional, Costa, Tássia Brena Barroso Carneiro, additional, Godoy, Michele Maria Gonçalves de, additional, Silva, Ronaldo Dionísio, additional, Santos, Joelma Carvalho, additional, Lira, Mariana Montenegro de Melo, additional, Jucá, Norma Thomé, additional, Lopes, Edmundo Pessoa de Almeida, additional, and Silva, Ricardo Oliveira, additional
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- 2018
- Full Text
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4. A convenient synthesis and cytotoxic activity of 3-aryl-5-pentyl-1,2,4-oxadiazoles from carboxylic acid esters and arylamidoximes under solvent-free conditions
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Barros, Carlos Jonnatan Pimentel, Souza, Zilyane Cardoso de, Freitas, Jucleiton José Rufino de, Silva, Paulo Bruno Norberto da, Militão, Gardenia Carmen Gadelha, Silva, Teresinha Gonçalves da, Freitas, Juliano Carlo Rufino, and Freitas Filho, João Rufino de
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Frutas ,Ésteres - Abstract
The synthesis of 3-aryl-5-pentyl-1,2,4-oxadiazoles from carboxylic acid esters and arylamidoximes in the presence of potassium carbonate is described. The reaction was carried out in a microwave oven without any solvent in much shorter time and in good yields. The structures of the synthesized compounds were elucidated using IR, 1H and 13C NMR spectroscopy and elemental analysis and their antiproliferative activities was evaluated against three different human cell lines.
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- 2014
5. Synthesis and characterization of novel 1,2,4-oxadiazoles and 2,3-unsaturated glycosides
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BARROS, Carlos Jonnatan Pimentel, FREITAS FILHO, João Rufino de, RAMOS, Clécio Souza, MELO, Sebastião José de, and SILVA, Ricardo Oliveira da
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QUIMICA [CIENCIAS EXATAS E DA TERRA] ,Glicosídeo ,Amidoximas ,Oxadiazol - Abstract
Submitted by (lucia.rodrigues@ufrpe.br) on 2017-02-13T14:05:22Z No. of bitstreams: 1 Carlos Jonnatan Pimentel Barros.pdf: 2792809 bytes, checksum: e6e2921a4590ac0ebec180e7f288314f (MD5) Made available in DSpace on 2017-02-13T14:05:22Z (GMT). No. of bitstreams: 1 Carlos Jonnatan Pimentel Barros.pdf: 2792809 bytes, checksum: e6e2921a4590ac0ebec180e7f288314f (MD5) Previous issue date: 2012-02-13 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES In this work, we drescribed the synthesis and characterization of novel 1,2,4-oxadiazoles and 2,3-unsaturated glycosides, containing heterocyclic ring or terpene units as aglycone. The synthesis of alkyl and arylamidoximes was carried out using two methods: the first was using household microwave irradiation and the second in ultrasound-bath. The alkyl and arylamidoximes 18a-l were obtained with good yields and reduced time for the first two methods compared with the methods found in the literature. The new 1,2,4-oxadiazoles and bis-1,2,4-oxadiazoles were obtained by two methods: at reflux and by microwave irradiation. The 3-aryl-5-pentyl-1,2,4-oxadiazoles (46a-f) were obtained from methyl hexanoate. The bis-1,2,4-oxadiazoles 3,3’-aryl-5,5’-bis-1,2,4-oxadiazolyl propan-2-one (47a-h), 1,2-dihydroxy-1,2-bis [3-aryl-1,2,4-oxadiazol-5-yl]-ethane (48a-h) and 1,2-bis-(3-aryl-1,2,4-oxadiazol-5-yl)ethanol (49a-h) were obtained from the following esters, respectively: diethyl 3-oxoglutarate, dimethyl malate and diethyl tartarate. The novel 2,3-unsaturated O-glycosides were obtained from the Ferrier rearrangement of tri-O-acetyl-D-glucal with alcohols: 2-(3-thienyl)ethanol, citronellol and geraniol. The glycosides were subjected to reactions of basic hydrolysis and allylic oxidation. The structures of the compounds obtained were elucidated by conventional spectroscopic techniques: Infrared and Magnetic Nuclear Resonance 1H and 13C. Neste trabalho, foi descrito a síntese e caracterização de inéditos 1,2,4-oxadiazóis e O-glicosídeos 2,3-insaturados, contendo anel heterocíclico ou unidades terpênicas como aglicona. A síntese de alquil e arilamidoximas foi realizada através de duas metodologias: a primeira consistiu na utilização de irradiação de microondas doméstico, a segunda em banho de ultrassom. As alquil e arilamidoximas 18a-l foram obtidas com bons rendimentos (40-92%) em tempos reduzidos quando comparado os dois primeiros métodos com os métodos encontrados na literatura. Os novos 1,2,4-oxadiazóis e bis-1,2,4-oxadiazóis foram obtidos através de duas metodologias: em refluxo e por irradiação de microondas. Os 3-aril-5-pentil-1,2,4-oxadiazóis (46a-f) foram obtidos a partir do hexanoato de metila e os bis-1,2,4-oxadiazóis 3,3’-aril-5,5’-bis-1,2,4-oxadiazolil propan-2-ona (47a-h), 1,2-diidroxi-1,2-bis[3-aril-1,2,4-oxadiazol-5-il]-etano (48a-h) e 1,2-bis-(3-aril-1,2,4-oxadiazol-5-il)-etanol (49a-h) foram obtidos a partir dos seguintes ésteres, respectivamente: 3-oxoglutarato de dietila, tartarato de dietila e malato de dimetila. Os O-glicosídeos 2,3-insaturados inéditos foram obtidos a partir do Rearranjo de Ferrier do tri-O-acetil-D-glucal com os álcoois: 2-(3-tienil)etanol, geraniol e citronelol . Os glicosídeos obtidos foram submetidos à reação de hidrólise básica e de oxidação alílica. As estruturas compostos obtidos foram elucidadas através de técnicas espectroscópicas convencionais: Infravermelho e Ressonância Magnética Nuclear de 1H e 13C.
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- 2012
6. Discriminating gamma-irradiated soybean seeds by 1H NMR-based metabonomics.
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Ribeiro, Abene Silva, Gouveia, Liana Ribeiro, Barros, Carlos Jonnatan Pimentel, Firmino, Paulo Renato Alves, and Silva, Ricardo Oliveira
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SOYBEAN , *SEEDS , *EFFECT of gamma rays on plants , *NUCLEAR magnetic resonance , *CHLOROFORM , *PLANT extracts , *FATTY acids - Abstract
Abstract: Gamma irradiation has been paramount for enhancing the quality of grain production, mainly in terms of distribution and storage. Gamma irradiation classification models for soybeans, however, are still in development. In this paper, we present a metabonomic model able to distinguish between gamma-irradiated and non-irradiated soybeans. The metabonomic model works on 1H NMR spectra of chloroform extracts and makes use of PCA and PLS-DA formalisms to classify the samples and to investigate which spectral bins are discriminatory. The model has presented an accuracy of 100% in the face of a real dataset involving 49 samples from diverse cultivars. In turn, the most important chemical shifts (δ) for discriminating among the samples were δ 1.57 and 1.62 ppm, which are assigned to β-carboxyl methylene groups of aliphatic chains of fatty acids. Besides, the gamma-irradiated samples showed an increasing in the integration areas at δ 1.57 ppm (assigned to free fatty acid) whilst non-irradiated samples showed an increasing in the integration areas at δ 1.62 ppm (assigned to fatty acids linked to glycerol as esters). [Copyright &y& Elsevier]
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- 2014
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