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1.
Mater Today Chem ; 25: 100924, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35475288

RESUMO

Due to the unprecedented and ongoing nature of the coronavirus outbreak, the development of rapid immunoassays to detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its highly contagious variants is an important and challenging task. Here, we report the development of polyclonal antibody-functionalized spherical gold nanoparticle biosensors as well as the influence of the nanoparticle sizes on the immunoassay response to detect the SARS-CoV-2 spike protein by dynamic light scattering. By monitoring the increment in the hydrodynamic diameter (ΔDH) by dynamic light scattering measurements in the antigen-antibody interaction, SARS-CoV-2 S-protein can be detected in only 5 min. The larger the nanoparticles, the larger ΔDH in the presence of spike protein. From adsorption isotherm, the calculated binding constant (K D ) was 83 nM and the estimated limit of detection was 13 ng/mL (30 pM). The biosensor was stable up to 90 days at 4 °C. Therefore, the biosensor developed in this work could be potentially applied as a fast and sensible immunoassay to detect SARS-CoV-2 infection in patient samples.

2.
Eur J Nucl Med Mol Imaging ; 46(11): 2235-2243, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31367906

RESUMO

PURPOSE: Patients with stage III non-small-cell lung cancer (NSCLC) treated with chemoradiotherapy (CRT) in low- and middle-income countries (LMIC) continue to have a poor prognosis. It is known that FDG PET/CT improves staging, treatment selection and target volume delineation (TVD), and although its use has grown rapidly, it is still not widely available in LMIC. CRT is often used as sequential treatment, but is known to be more effective when given concurrently. The aim of the PERTAIN study was to assess the impact of introducing FDG PET/CT-guided concurrent CRT, supported by training and quality control (QC), on the overall survival (OS) and progression-free survival (PFS) of patients with stage III NSCLC. METHODS: The study included patients with stage III NSCLC from nine medical centres in seven countries. A retrospective cohort was managed according to local practices between January 2010 and July 2014, which involved only optional diagnostic FDG PET/CT for staging (not for TVD), followed by sequential or concurrent CRT. A prospective cohort between August 2015 and October 2018 was treated according to the study protocol including FDG PET/CT in treatment position for staging and multimodal TVD followed by concurrent CRT by specialists trained in protocol-specific TVD and with TVD QC. Kaplan-Meier analysis was used to assess OS and PFS in the retrospective and prospective cohorts. RESULTS: Guidelines for FDG PET/CT image acquisition and TVD were developed and published. All specialists involved in the PERTAIN study received training between June 2014 and May 2016. The PET/CT scanners used received EARL accreditation. In November 2018 a planned interim analysis was performed including 230 patients in the retrospective cohort with a median follow-up of 14 months and 128 patients in the prospective cohort, of whom 69 had a follow-up of at least 1 year. Using the Kaplan-Meier method, OS was significantly longer in the prospective cohort than in the retrospective cohort (23 vs. 14 months, p = 0.012). In addition, median PFS was significantly longer in the prospective cohort than in the retrospective cohort (17 vs. 11 months, p = 0.012). CONCLUSION: In the PERTAIN study, the preliminary results indicate that introducing FDG PET/CT-guided concurrent CRT for patients with stage III NSCLC in LMIC resulted in a significant improvement in OS and PFS. The final study results based on complete data are expected in 2020.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Quimiorradioterapia , Neoplasias Pulmonares/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil , Carcinoma Pulmonar de Células não Pequenas/terapia , Intervalo Livre de Doença , Estônia , Feminino , Fluordesoxiglucose F18 , Humanos , Processamento de Imagem Assistida por Computador , Índia , Jordânia , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/terapia , Masculino , Pessoa de Meia-Idade , Paquistão , Estudos Prospectivos , Controle de Qualidade , Planejamento da Radioterapia Assistida por Computador , Estudos Retrospectivos , Resultado do Tratamento , Turquia , Vietnã
3.
Virology ; 464-465: 385-396, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25117897

RESUMO

The emergence of viruses in Coffee (Coffea arabica and Coffea canephora), the most widely traded agricultural commodity in the world, is of critical concern. The RNA1 (6552nt) of Coffee ringspot virus is organized into five open reading frames (ORFs) capable of encoding the viral nucleocapsid (ORF1p), phosphoprotein (ORF2p), putative cell-to-cell movement protein (ORF3p), matrix protein (ORF4p) and glycoprotein (ORF5p). Each ORF is separated by a conserved intergenic junction. RNA2 (5945nt), which completes the bipartite genome, encodes a single protein (ORF6p) with homology to RNA-dependent RNA polymerases. Phylogenetic analysis of L protein sequences firmly establishes CoRSV as a member of the recently proposed Dichorhavirus genus. Predictive algorithms, in planta protein expression, and a yeast-based nuclear import assay were used to determine the nucleophillic character of five CoRSV proteins. Finally, the temperature-dependent ability of CoRSV to establish systemic infections in an initially local lesion host was quantified.


Assuntos
Coffea/virologia , Doenças das Plantas/virologia , Rhabdoviridae/isolamento & purificação , Sequência de Aminoácidos , Sequência de Bases , Coffea/química , Genoma Viral , Dados de Sequência Molecular , Fases de Leitura Aberta , Filogenia , Rhabdoviridae/química , Rhabdoviridae/classificação , Rhabdoviridae/genética , Sementes/química , Sementes/virologia , Alinhamento de Sequência , Proteínas Virais/química , Proteínas Virais/genética
4.
Int Braz J Urol ; 32(4): 405-9, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16953906

RESUMO

OBJECTIVE: The aim of this study was to compare the renal function measured with either 99mTc-DTPA or 99mTc-EC dynamic scintigraphies with that measured using 99mTc-DMSA static scintigraphy. METHODS: the values of relative renal function measured in 111 renal dynamic scintigraphies performed either with 99mTc-DTPA (55 studies) or with 99mTc-EC (56 studies) were compared with the relative function measured using 99mTc-DMSA static scintigraphy performed within a 1-month period. The comparisons were performed using Wilcoxon signed rank test. The number of 99mTc-DTPA and 99mTc-EC studies that presented relative renal function different by more than 5% from that measured with 99mTc-DMSA, using chi square test were also compared. RESULTS: the relative renal function measured with 99mTc-EC is not statistically different from that measured with 99mTc-DMSA (p = 0.97). The relative renal function measured with 99mTc-DTPA was statistically different from that measured using 99mTc-DMSA, but with a borderline statistical significance (p = 0.05). The number of studies with relative renal function different by more than 5% from that measured with 99mTc-DMSA is higher for the 99mTc-DTPA scintigraphy (p = 0.04) than for 99mTc-EC. CONCLUSION: the relative renal function measured with 99mTc-EC dynamic scintigraphy is comparable with that measured with 99mTc-DMSA static scintigraphy, while the relative renal function measured with 99mTc-DTPA dynamic scintigraphy presents a significant statistical difference from that measured with 99mTc-DMSA static scintigraphy.


Assuntos
Compostos Radiofarmacêuticos , Obstrução da Artéria Renal/diagnóstico por imagem , Ácido Dimercaptossuccínico Tecnécio Tc 99m , Pentetato de Tecnécio Tc 99m , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Lactente , Recém-Nascido , Testes de Função Renal/métodos , Masculino , Pessoa de Meia-Idade , Cintilografia , Compostos Radiofarmacêuticos/farmacocinética , Reprodutibilidade dos Testes , Ácido Dimercaptossuccínico Tecnécio Tc 99m/farmacocinética , Pentetato de Tecnécio Tc 99m/farmacocinética
5.
Int. braz. j. urol ; 32(4): 405-409, July-Aug. 2006. ilus, tab
Artigo em Inglês | LILACS | ID: lil-436883

RESUMO

OBJECTIVE: The aim of this study was to compare the renal function measured with either 99mTc-DTPA or 99mTc-EC dynamic scintigraphies with that measured using 99mTc-DMSA static scintigraphy. METHODS: the values of relative renal function measured in 111 renal dynamic scintigraphies performed either with 99mTc-DTPA (55 studies) or with 99mTc-EC (56 studies) were compared with the relative function measured using 99mTc-DMSA static scintigraphy performed within a 1-month period. The comparisons were performed using Wilcoxon signed rank test. The number of 99mTc-DTPA and 99mTc-EC studies that presented relative renal function different by more than 5 percent from that measured with 99mTc-DMSA, using chi square test were also compared. RESULTS: the relative renal function measured with 99mTc-EC is not statistically different from that measured with 99mTc-DMSA (p = 0.97). The relative renal function measured with 99mTc-DTPA was statistically different from that measured using 99mTc-DMSA, but with a borderline statistical significance (p = 0.05). The number of studies with relative renal function different by more than 5 percent from that measured with 99mTc-DMSA is higher for the 99mTc-DTPA scintigraphy (p = 0.04) than for 99mTc-EC. CONCLUSION: the relative renal function measured with 99mTc-EC dynamic scintigraphy is comparable with that measured with 99mTc-DMSA static scintigraphy, while the relative renal function measured with 99mTc-DTPA dynamic scintigraphy presents a significant statistical difference from that measured with 99mTc-DMSA static scintigraphy.


Assuntos
Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos , Obstrução da Artéria Renal , Interpretação de Imagem Assistida por Computador , Testes de Função Renal/métodos , Reprodutibilidade dos Testes , Compostos Radiofarmacêuticos/farmacocinética , /farmacocinética , /farmacocinética
6.
Braz J Med Biol Res ; 39(1): 9-18, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16400460

RESUMO

Coronary artery disease (CAD) is a worldwide leading cause of death. The standard method for evaluating critical partial occlusions is coronary arteriography, a catheterization technique which is invasive, time consuming, and costly. There are noninvasive approaches for the early detection of CAD. The basis for the noninvasive diagnosis of CAD has been laid in a sequential analysis of the risk factors, and the results of the treadmill test and myocardial perfusion scintigraphy (MPS). Many investigators have demonstrated that the diagnostic applications of MPS are appropriate for patients who have an intermediate likelihood of disease. Although this information is useful, it is only partially utilized in clinical practice due to the difficulty to properly classify the patients. Since the seminal work of Lotfi Zadeh, fuzzy logic has been applied in numerous areas. In the present study, we proposed and tested a model to select patients for MPS based on fuzzy sets theory. A group of 1053 patients was used to develop the model and another group of 1045 patients was used to test it. Receiver operating characteristic curves were used to compare the performance of the fuzzy model against expert physician opinions, and showed that the performance of the fuzzy model was equal or superior to that of the physicians. Therefore, we conclude that the fuzzy model could be a useful tool to assist the general practitioner in the selection of patients for MPS.


Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Teste de Esforço , Lógica Fuzzy , Seleção de Pacientes , Adulto , Idoso , Doença da Artéria Coronariana/classificação , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Perfusão , Cintilografia , Fatores de Risco , Sensibilidade e Especificidade , Índice de Gravidade de Doença
7.
Braz. j. med. biol. res ; 39(1): 9-18, Jan. 2006. tab, graf
Artigo em Inglês | LILACS | ID: lil-419148

RESUMO

Coronary artery disease (CAD) is a worldwide leading cause of death. The standard method for evaluating critical partial occlusions is coronary arteriography, a catheterization technique which is invasive, time consuming, and costly. There are noninvasive approaches for the early detection of CAD. The basis for the noninvasive diagnosis of CAD has been laid in a sequential analysis of the risk factors, and the results of the treadmill test and myocardial perfusion scintigraphy (MPS). Many investigators have demonstrated that the diagnostic applications of MPS are appropriate for patients who have an intermediate likelihood of disease. Although this information is useful, it is only partially utilized in clinical practice due to the difficulty to properly classify the patients. Since the seminal work of Lotfi Zadeh, fuzzy logic has been applied in numerous areas. In the present study, we proposed and tested a model to select patients for MPS based on fuzzy sets theory. A group of 1053 patients was used to develop the model and another group of 1045 patients was used to test it. Receiver operating characteristic curves were used to compare the performance of the fuzzy model against expert physician opinions, and showed that the performance of the fuzzy model was equal or superior to that of the physicians. Therefore, we conclude that the fuzzy model could be a useful tool to assist the general practitioner in the selection of patients for MPS.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Doença da Artéria Coronariana , Teste de Esforço , Lógica Fuzzy , Seleção de Pacientes , Doença da Artéria Coronariana/classificação , Seguimentos , Modelos Teóricos , Perfusão , Fatores de Risco , Sensibilidade e Especificidade , Índice de Gravidade de Doença
8.
Braz J Med Biol Res ; 38(2): 261-70, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15785838

RESUMO

The objective of the present study was to translate the Kidney Disease Quality of Life -- Short Form (KDQOL-SF 1.3) questionnaire into Portuguese to adapt it culturally and validate it for the Brazilian population. The KDQOL-SF was translated into Portuguese and back-translated twice into English. Patient difficulties in understanding the questionnaire were evaluated by a panel of experts and solved. Measurement properties such as reliability and validity were determined by applying the questionnaire to 94 end-stage renal disease patients on chronic dialysis. The Nottingham Health Profile Questionnaire, the Karnofsky Performance Scale and the Kidney Disease Questionnaire were administered to test validity. Some activities included in the original instrument were considered to be incompatible with the activities usually performed by the Brazilian population and were replaced. The mean scores for the 19 components of the KDQOL-SF questionnaire in Portuguese ranged from 22 to 91. The components "Social support" and "Dialysis staff encouragement" had the highest scores (86.7 and 90.8, respectively). The test-retest reliability and the inter-observer reliability of the instrument were evaluated by the intraclass correlation coefficient. The coefficients for both reliability tests were statistically significant for all scales of the KDQOL-SF (P < 0.001), ranging from 0.492 to 0.936 for test-retest reliability and from 0.337 to 0.994 for inter-observer reliability. The Cronbach's alpha coefficient was higher than 0.80 for most of components. The Portuguese version of the KDQOL-SF questionnaire proved to be valid and reliable for the evaluation of quality of life of Brazilian patients with end-stage renal disease on chronic dialysis.


Assuntos
Falência Renal Crônica/psicologia , Qualidade de Vida , Inquéritos e Questionários/normas , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil , Características Culturais , Feminino , Humanos , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Diálise Renal , Reprodutibilidade dos Testes , Tradução
9.
Braz. j. med. biol. res ; 38(2): 261-270, fev. 2005. tab
Artigo em Inglês | LILACS | ID: lil-393649

RESUMO

The objective of the present study was to translate the Kidney Disease Quality of Life - Short Form (KDQOL-SFÕ1.3) questionnaire into Portuguese to adapt it culturally and validate it for the Brazilian population. The KDQOL-SF was translated into Portuguese and back-translated twice into English. Patient difficulties in understanding the questionnaire were evaluated by a panel of experts and solved. Measurement properties such as reliability and validity were determined by applying the questionnaire to 94 end-stage renal disease patients on chronic dialysis. The Nottingham Health Profile Questionnaire, the Karnofsky Performance Scale and the Kidney Disease Questionnaire were administered to test validity. Some activities included in the original instrument were considered to be incompatible with the activities usually performed by the Brazilian population and were replaced. The mean scores for the 19 components of the KDQOL-SF questionnaire in Portuguese ranged from 22 to 91. The components "Social support" and "Dialysis staff encouragement" had the highest scores (86.7 and 90.8, respectively). The test-retest reliability and the inter-observer reliability of the instrument were evaluated by the intraclass correlation coefficient. The coefficients for both reliability tests were statistically significant for all scales of the KDQOL-SF (P < 0.001), ranging from 0.492 to 0.936 for test-retest reliability and from 0.337 to 0.994 for inter-observer reliability. The Cronbach's alpha coefficient was higher than 0.80 for most of components. The Portuguese version of the KDQOL-SF questionnaire proved to be valid and reliable for the evaluation of quality of life of Brazilian patients with end-stage renal disease on chronic dialysis.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Falência Renal Crônica/psicologia , Qualidade de Vida , Inquéritos e Questionários/normas , Tradução , Brasil , Características Culturais , Falência Renal Crônica/terapia , Diálise Renal , Reprodutibilidade dos Testes
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