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Porphyrins and phthalocyanines are promising π-conjugated compounds with fantastic photochemical and electrochemical properties which are present in nature in more systems than we are generally aware. The electrochemical properties of these large aromatic molecules are also unique, endowing them with the ability to catalyze a wide range of redox reactions. The macrocycle core of these molecules is extremely favorable for the complexation of several metal ions, resulting in molecules with tunable properties. Porphyrins and phthalocyanines are able to form highly organized films, with high conductivity and great robustness and their use was explored to build a great number of electrochemical and photoelectrochemical sensors for many varied applications, one among them being drug analysis. This review will focus on the potential of the electrodes modified with attractive porphyrins and phthalocyanines for this application. The papers published in the last 3 years were closely evaluated.
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Eletroquímica/métodos , Indóis/química , Compostos Macrocíclicos/química , Preparações Farmacêuticas/análise , Porfirinas/química , IsoindóisRESUMO
The structure of polytetraruthenated nickel porphyrin was unveiled for the first time by electrochemistry, Raman spectroelectrochemistry, and a hydroxyl radical trapping assay. The electrocatalytic active material, precipitated on the electrode surface after successive cycling of [NiTPyP{Ru(bipy)2Cl}4](4+) species in strong aqueous alkaline solution (pH 13), was found to be a peroxo-bridged coordination polymer. The electropolymerization process involves hydroxyl radicals (as confirmed by the characteristic set of DMPO/(â¢)OH adduct EPR peaks) as reaction intermediates, electrocatalytically generated in the 0.80-1.10 V range, that induce the formation of Ni-O-O-Ni coordination polymers, as evidenced by Raman spectroelectrochemistry and molecular modeling studies. The film growth is halted above 1.10 V due to the formation of oxygen gas bubbles.
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To help meet the global demand for reliable and inexpensive COVID-19 testing and environmental analysis of SARS-CoV-2, the present work reports the development and application of a highly efficient disposable electrochemical immunosensor for the detection of SARS-CoV-2 in clinical and environmental matrices. The sensor developed is composed of a screen-printed electrode (SPE) array which was constructed using conductive carbon ink printed on polyethylene terephthalate (PET) substrate made from disposable soft drink bottles. The recognition site (Spike S1 Antibody (anti-SP Ab)) was covalently immobilized on the working electrode surface, which was effectively modified with carbon black (CB) and gold nanoparticles (AuNPs). The immunosensing material was subjected to a multi-technique characterization analysis using X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM) with elemental analysis via energy dispersive spectroscopy (EDS). The electrochemical characterization of the electrode surface and analytical measurements were performed using cyclic voltammetry (CV) and square-wave voltammetry (SWV). The immunosensor was easily applied for the conduct of rapid diagnoses or accurate quantitative environmental analyses by setting the incubation period to 10 min or 120 min. Under optimized conditions, the biosensor presented limits of detection (LODs) of 101 fg mL-1 and 46.2 fg mL-1 for 10 min and 120 min incubation periods, respectively; in addition, the sensor was successfully applied for SARS-CoV-2 detection and quantification in clinical and environmental samples. Considering the costs of all the raw materials required for manufacturing 200 units of the AuNP-CB/PET-SPE immunosensor, the production cost per unit is 0.29 USD.
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BACKGROUND: Breast cancer is one of the most common types among women. Its incidence progressively increases with age, especially after age 50. Platinum compounds are not efficient in the treatment of breast cancer, highlighting the use of other metals for the development of new chemotherapeutic agents. OBJECTIVE: This paper aims to obtain three new ruthenium compounds that incorporate sulfur amino acids in their structures and to investigate their cytotoxic activity in breast tumor cell lines. METHODS: Complexes with general formula [Ru(AA)(dppb)(bipy)] (complexes 1 and 2) or [Ru(AA)(dppb) (bipy)]PF6 (complex 3), where AA = L-cysteinate (1), D-penicillaminate (2), and L-deoxyalliinate (3), dppb = 1,4-bis(diphenylphosphino)butane and 2,2´-bipyridine, were obtained from the cis-[RuCl2(dppb)(bipy)] precursor. The cytotoxicity of the complexes on MDA-MB-231 (triple negative human breast cancer); MCF-7 (double positive human breast cancer) and V79 (hamster lung fibroblast) was performed by the MTT (4,5- dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide) method. The control agent was the cisplatin, which is a commercially available drug for cancer treatment. RESULTS: In complexes (1) and (2), the ligands are coordinated to the metal center by nitrogen and sulfur atoms, while in complex (3), coordination is through the oxygen and nitrogen atoms. These suggestions are based on the infrared and 31P{1H} NMR data. For complexes (1) and (2), their X-ray structures were determined confirming this suggestion. The three complexes are stable in a mixture of DMSO (80%) and biological medium (20%) for at least 48h and presented cytotoxicity against the MDA-MB-231 and MCF-7 tumor cells with reasonable selectivity indexes. CONCLUSION: Our work demonstrated that ruthenium complexes containing sulfur amino acids, bipyridines and bisphosphines showed cytotoxicity against the MDA-MB-231 and MCF-7 cancer cell lines, in vitro, and that they interact weakly with the DNA (Deoxyribonucleic Acid) and the HSA (Human Serum Albumin) biomolecules.
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Aminoácidos/farmacologia , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Complexos de Coordenação/farmacologia , Rutênio/farmacologia , Enxofre/farmacologia , Aminoácidos/química , Antineoplásicos/síntese química , Antineoplásicos/química , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , DNA/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Rutênio/química , Albumina Sérica Humana/química , Relação Estrutura-Atividade , Enxofre/químicaRESUMO
BACKGROUND: Sickle cell disease is a prevalent condition in Brazil. Its clinical presentation includes vascular occlusion that result in ischemia, inflammation, dysfunctions, pain and chronic hemolysis, causing irreversible damage and compromising quality of life. OBJECTIVE: The objectives of this study were to verify the relationship between musculoskeletal pain, from different body parts, with social economic characteristics and quality of life among individuals with sickle cell disease. METHODS: 27 individuals with sickle cell disease were interviewed with the use of a structured questionnaire with questions about personal, social, economic and cultural variables, the Nordic musculoskeletal symptoms questionnaire and the SF-36 Health Survey. Data were analyzed descriptively using frequencies and percentages. The inferential Chi-Square test was used for dichotomous variables and the Student t- test for continuous variables, with a significance of 5%. A logistic regression was performed using all variables that correlated with pain as dependent variables. RESULTS: The mean age was 31.77 years, predominantly male, black, registered active employment, with average education and income up to three minimum wages. The regions most affected by pain were hip/limbs, chest, lower back and arms. Physical Functioning from the SF-36 had the highest score and mental health the lowest score. Musculoskeletal pain was present in the arms, chest and lower back. Social Functioning was not associated with pain, indicating the influence of other factors. Arm pain was more frequent in black individuals and those with low education. CONCLUSION: Body pain was associated with race and education and all pain areas were associated with the physical components of the SF-36. Pain was significantly associated with vitality and mental health components of the SF-36.
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Anemia Falciforme/complicações , Dor Musculoesquelética/etiologia , Qualidade de Vida , Adulto , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Masculino , Fatores Socioeconômicos , Inquéritos e QuestionáriosRESUMO
BACKGROUND: Sickle cell disease is a prevalent condition in Brazil. Its clinical presentation includes vascular occlusion that result in ischemia, inflammation, dysfunctions, pain and chronic hemolysis, causing irreversible damage and compromising quality of life. OBJECTIVE: The objectives of this study were to verify the relationship between musculoskeletal pain, from different body parts, with social economic characteristics and quality of life among individuals with sickle cell disease. METHODS: 27 individuals with sickle cell disease were interviewed with the use of a structured questionnaire with questions about personal, social, economic and cultural variables, the Nordic musculoskeletal symptoms questionnaire and the SF-36 Health Survey. Data were analyzed descriptively using frequencies and percentages. The inferential Chi-Square test was used for dichotomous variables and the Student t- test for continuous variables, with a significance of 5%. A logistic regression was performed using all variables that correlated with pain as dependent variables. RESULTS: The mean age was 31.77 years, predominantly male, black, registered active employment, with average education and income up to three minimum wages. The regions most affected by pain were hip/limbs, chest, lower back and arms. Physical Functioning from the SF-36 had the highest score and mental health the lowest score. Musculoskeletal pain was present in the arms, chest and lower back. Social Functioning was not associated with pain, indicating the influence of other factors. Arm pain was more frequent in black individuals and those with low education. CONCLUSION: Body pain was associated with race and education and all pain areas were associated with the physical components of the SF-36. Pain was significantly associated with vitality and mental health components of the SF-36.
CONTEXTUALIZAÇÃO: As doenças falciformes constituem um grupo frequente no Brasil. Suas alterações ocasionam vaso-oclusão, resultando em isquemia, inflamação, disfunções, dor e hemólise crônica, gerando danos irreversíveis, comprometendo a qualidade de vida. OBJETIVO: Verificar a relação entre a dor osteomuscular, considerando sua localização corporal, e características sociais, econômicas e de qualidade de vida em indivíduos com doença falciforme. MÉTODOS: Foram coletadas informações pessoais, sociais e econômicas, além de dados do Questionário Nórdico de Sintomas Osteomusculares (QNSO) e Short Form 36 em 27 indivíduos. Os dados foram analisados descritivamente por meio de frequências e porcentagens. A análise inferencial usou o teste do qui-quadrado (variáveis dicotômicas) e t de Student (variáveis contínuas), com significância de 5%. Análises de regressão logística utilizaram como variáveis dependentes cada uma das que se relacionaram com dor. RESULTADOS: A média de idade foi de 31,77 anos, predominando sexo masculino, negros, emprego ativo, escolaridade média e rendimento inferior a três salários mínimos. Quadril/membros inferiores, região dorsal, lombar e braços foram mais acometidos pela dor. A capacidade funcional apresentou o maior valor, e saúde mental, o menor. Aspectos físicos foram comprometidos pela dor nos braços, coluna dorsal e lombar. Aspectos sociais não se associaram com a dor, indicando influência de outros fatores. A dor nos braços foi mais frequente entre os negros e os com baixa escolaridade. CONCLUSÃO: A dor nas regiões corporais analisadas relacionou-se com a raça e a escolaridade e com todos os domínios referentes ao componente físico do SF-36. Os componentes vitalidade e saúde mental apresentaram associação significativa com a dor.
Assuntos
Adulto , Feminino , Humanos , Masculino , Anemia Falciforme/complicações , Dor Musculoesquelética/etiologia , Qualidade de Vida , Estudos de Coortes , Estudos Transversais , Fatores Socioeconômicos , Inquéritos e QuestionáriosRESUMO
Candidatos a doação são submetidos a triagem clínica e sorológica para minimizar o risco de transmissão de doenças via transfusão. Uma de suas limitações é a janela imunológica, que possibilita a transfusão de sangue contaminado. O objetivo deste trabalho foi avaliar o índice de autoexclusão de acordo com idade, gênero, estado civil, cor e tipo de doação, as variações anuais de autoexcluídos e sua eficácia em evitar a transfusão de sangue contaminado. Os dados foram analisados através do teste qui-quadrado, odds ratio e regressão linear. De 1996 a 2006, o Hemocentro Regional de Uberaba (HRU) coletou 176.097 bolsas de sangue, das quais 2,72 por cento foram desprezadas por autoexclusão, com significativo predomínio de homens, maiores de 29 anos, solteiros, não brancos e primeira doação (p<0,0001). Observou-se associação entre fidelização e autoexclusão, sugerindo que maior fidelização contribui para menor autoexclusão. A sorologia positiva para HIV1 (0,35 por cento) e HIV2 (0,23 por cento) foi significativamente maior nos autoexcluídos (p<0,0001), significância não observada para HCV (0,52 por cento) (p=0,24). Nos não autoexcluídos, estes percentuais foram de 0,15 por cento, 0,03 por cento e 0,41 por cento, respectivamente. A maior frequência de autoexclusão em homens maiores de 29 anos, solteiros e não brancos está de acordo, em parte, com o perfil do doador do HRU. O decréscimo de 1996 a 2001 é explicado por fatores comportamentais como criação do Centro de Testagem Anônima e maior fidelização dos doadores ao longo dos anos. A maior frequência de positividade nos autoexcluídos e três soroconversões em doações subsequentes reforçam a importância dessa ferramenta na diminuição do risco de janela imunológica.
Blood donor candidates are submitted to clinical and serological screening to minimize the risk of disease transmission. One of the limitations of this screening is the immunological window, a period that may contribute to the transfusion of contaminated blood. The aim of this study was to evaluate self-exclusion rates related to age, gender, marital status, race, type of donation, annual variations in self-exclusion and the efficacy of self-exclusion to prevent the transfusion of contaminated blood. A retrospective study was conducted and the data were analyzed using the chi-square test, odds ratio and linear regression. Of the 176,097 blood bags collected at the Uberaba Regional Blood Center (HRU) between 1996 and 2006, 2.72 percent were discarded due to self-exclusion. There was a predominance of first-time, unmarried, non-white male donors over the age of 29 years old (p<0.0001). An inverse association was observed between long-term commitment and self-exclusion, suggesting that the higher the return rate, the lower the incidence of self-exclusion. Positive serology for HIV1 (0.35 percent) and HIV2 (0.23 percent) was significantly higher among self-exclusion donors (p<0.0001), a fact not observed for HCV (0.52 percent) (p=0.24). The percentages of these three diseases were 0.15 percent, 0.03 percent and 0.41 percent, respectively among donors not initiating self-exclusion. The higher frequency of self-exclusion among unmarried, non-white male donors over the age of 29 partly agrees with the donor profile of HRU. The decline observed from 1996 to 2001 might be explained by behavioral factors, such as the creation of anonymous testing centers and an increase in the long-term commitment of donors over the years. The higher frequency of positivity among self-exclusion donors and only three seroconversions in subsequent donations support the importance of this tool to reduce the risk of contamination due to the immunological window.
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Humanos , Doadores de Sangue , Transfusão de Sangue , Sorologia , Transfusão de Sangue/normasRESUMO
Atualmente, um dos maiores problemas na triagem sorológica de doadores de sangue para doença de Chagas é a alta freqüência de reações indeterminadas, o que faz com que muitos indivíduos sadios sejam rotulados como portadores de uma doença grave. O presente trabalho tem o objetivo de analisar o comportamento sorológico para doença de Chagas dos doadores do Hemocentro Regional de Uberaba, MG e propor mecanismos para reduzir o índice de inaptidão sorológica para essa doença. Através de estudo retrospectivo, foi analisado o resultado sorológico de 79.729 amostras obtidas de doações de sangue realizadas neste Serviço entre janeiro de 2000 e dezembro de 2004. Os resultados foram analisados quanto às variáveis: tipo de doador (novo e de retorno), gênero e idade (inferior ou igual a 30 anos e superior a 30 anos). Para a análise estatística foram realizados os testes do Qui-Quadrado e de comparação de proporções (Z). A ocorrência de doações com sorologia não negativa para doença de Chagas entre doadores novos foi significativamente superior aos de retorno, com p< 0,0001. Quanto à idade, a proporção de positivos no grupo maior de 30 anos foi significativamente superior à do grupo com idade igual ou inferior a 30 anos (p< 0,0001). O elevado número de reações indeterminadas nesse Serviço está de acordo com estudos recentes, reforçando a necessidade da implementação de testes sorológicos 100 por cento específicos ou de exames confirmatórios práticos e rápidos, passíveis de serem introduzidos nas rotinas dos serviços de hemoterapia, reduzindo o descarte desnecessário de bolsas de sangue.
Currently one of the major problems in the serological selection of blood donors in respect to Chagas' disease is the high incidence of indeterminate reactions, making a large number of healthy individuals incorrectly diagnosed as seriously ill. This paper aims at evaluating the serological pattern of Chagas' disease of donors of the Uberaba Blood Center and also to propose mechanisms to reduce the rate of serological ineligibility due to suspicion of this disease. A retrospective study of the serological results of 79,729 samples of blood was carried out between January 2000 and December 2004. The results were analyzed according to the following variables: type of donor (first-time and multiple), gender and age (less than or equal to 30 or more than 30 years old). The statistical analysis was made using the chi-square test and a comparison of proportions (Z). Indeterminate results in respect to Chagas' disease among first-time donors were significantly higher than those of multiple donations with p < 0.0001. As for age, the proportion of positivity in the over 30-year-old group was significantly higher to that of the under or equal to 30-year-old group (p < 0.0001). The high number of indeterminate reactions at this center is in accordance with recent studies, highlighting the need of implementing serological tests with 100 percent specificity or the use of practical and fast confirmation tests to be routinely introduced in hemotherapy services, reducing the unnecessary rejection of blood bags.
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Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Análise Química do Sangue , Doadores de Sangue , Doença de ChagasRESUMO
Estudaram-se as relaçöes antigênicas de vinte amostras de Bordetella bronchiseptica recuperadas de suínos com rinite atrófica mediante um teste de soroaglutinaçäo quantitativo. Os títulos dos soros produzidos em coelhos contra cada um dos isolamentos foram determinados usando antígenos homólogos e heterólogos. Doze soros que apresentaram reatividade cruzada foram absorvidas e seus títulos determinados com antígenos heterólogos. Estimaram-se as relaçöes antigênicas entre os isolamentos calculando os índices de reatividade cruzada. Dois isolamentos apresentaram alta reatividade cruzada com outros 16, entretanto só um näo reagiu com o painel utilizado. Concluiu-se que B. bronchiseptica recuperada de suínos é antigenicamente heterogênea