Modified electrodes prepared with polyphenolic film containing ruthenium complex and metal ligand anchored by azo covalent bond

This work presents two new modified carbon electrodes which were prepared via the polymerization of a phenolic moiety previously functionalized with azo groups (bipyridine and 2-methoxypyridine) as key structures to anchor the desired ligands. The syntheses of BAP (4-([2,2’]-bipyridinyl-4-ylazo)-phenol) and PAPmethoxy (5-(4-hidroxyphenylazo) pyridin-2-methoxy) were simple to perform, gave good yields and the monomers were easily electropolymerized resulting in chemically and mechanically stable modified electrodes. The PAP-methoxy ME formed stable complexes with Cd, Cu and Pb in aqueous media at open circuit and produced well defined redox peaks, showing good potential for future analytical applications. The BAP monomer was used to produce a ruthenium complex (BAP-Ru) which was electropolymerized from +0.50 to +0.75V (vs. Ag/AgCl) to leave the ruthenium available to act as a catalyst. The BAP-Ru ME was able to oxidize a variety of organic substrates with good selectivity. The yields obtained were either similar to, or better than, those obtained by homogeneous catalysis using a similar ruthenium catalyst or when this type of catalyst is supported in a carbon paste electrode.Este trabalho apresenta dois novos eletrodos de grafite modificados que foram preparados via polimerização da função fenólica, previamente funcionalizada por grupos azo (bipiridina e 2-metoxipiridina), que atuam como estruturas chaves para a ancoragem de ligantes de interesse. As sínteses dos monômeros BAP (4-([2,2’]bipiridinil-4-ilazo)-fenol) e PAPmetóxi (5-(4-hidroxifenilazo)piridin-2-metóxi) foram simples, deram bons rendimentos e os monômeros foram facilmente eletropolimerizados, levando à formação de eletrodos modificados (EM) química e mecanicamente estáveis. Em solução aquosa e em circuito aberto, o EM PAP-metóxi formou complexos estáveis com Cd, Cu e Pb, produzindo picos redox bem definidos, demonstrando o grande potencial deste eletrodo para futuras aplicações analíticas. O monômero BAP foi utilizado para produzir um complexo de rutênio (BAP-Ru) que foi eletropolimerizado entre +0.50 e +0.75V (vs. Ag/AgCl), permitindo que o rutênio permanecesse disponível para atuar como catalisador. O EM BAP-Ru oxidou seletivamente uma variedade de substratos orgânicos dando produtos com rendimentos próximos ou melhores que aqueles obtidos por catálise homogênea com complexos de rutênio similares, ou quando este tipo de catalisador é impregnado em pasta de carbono.CNPqCoordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES

Avaliação de Impactos Ambientais : um estudo na operação do Porto de Ita jaí

A necessidade de um melhor gerenciamento das questões ambientais, envolvendo o uso de instrumentos de gestão existentes, vem sendo assunto de variados estudos, principalmente no que tange a avaliação de impactos ambientais, sugerida na norma ISO 14001. Entretanto, o tema não está totalmente incorporado em algumas áreas, como no setor portuário. Sendo assim, o presente estudo avalia aspectos e impactos ambientais envolvidos dentro das atividades produtivas para o caso específico das operações do Porto de Itajaí. Dentro da concretização do estudo, buscou-se um referencial teórico abrangente e fez-se um levantamento das principais metodologias envolvidas nas avaliações de aspectos e impactos no âmbito de Sistemas de Gestão Ambiental, tendo como escolha o uso do método SGADA, que, dentre alguns critérios de adaptação e compatibilidade foi aquele que melhor se enquadrou com o problema proposto. A aplicação do método foi direcionada à atividade operacional do porto, com o intuito de obter-se uma avaliação de significância de cada aspecto e impacto ambiental gerado. Os resultados mais expressivos dentro da operação do porto apontam para a contaminação da água envolvendo a utilização de efluentes líquidos oleosos e a potencialidade de acidentes gerados por incêndios, embora este último possa ser amenizado através de programas e ações emergenciais implantadas. De modo específico, os resultados de caráter mais grave no Porto. Em geral, o estudo permitiu inferir que a avaliação dos aspectos e impactos ambientais, além de identificar os pontos de mais cuidado e atenção dentro da organização, possibilita que suas atividades e áreas sejam aperfeiçoadas, visando menor (ou nenhum) dano ao ambiente inserido

Green speciation of iron using aqueous two-phase system

Fe(II) and Fe(III) have distinct chemical and biological functions. Consequently, it is more important to determine the fraction of both oxidation state that knowing the total iron concentration in a sample. However, green methods for iron speciation are still limited. This work uses aqueous two-phase system, a safe alternative to liquid–liquid extraction, to perform the chemical speciation of iron. This method is based on the reaction of Fe(II) with 1,10-phenanthroline extractant, forming a complex of Fe(II)-phenanthroline that concentrates in the top phase of the system. The Fe(III) specie concentrated in the bottom phase of the system. Iron speciation was affected by the electrolyte nature, macromolecule type, quantity of phenanthroline added, and pH. The system formed by PEO1500 + Na3 C6 H5 O7 + H2 O at pH 6.00, containing 5.00 mmol kg–1 of phenanthroline, was successfully used to separate the iron species before determination by flame atomic absorption spectrometry. Under these optimal conditions, a separation factor of 233 was obtained between Fe(II) and Fe(III) with extraction percentages of (95.1 ± 1.0)% and (7.68 ± 0.50)%, respectively The proposed method was successfully applied for iron speciation in water samples, and provided recovery percentages ranging between 90 and 106%

Diversidade de Coccinellidae (Coleoptera) em plantas aromáticas (Apiaceae) como sítios de sobrevivência e reprodução em sistema agroecológico.

Studies show that Apiaceae may provide concentrated vital resources for predator insects,stimulating their abundance, diversity and persistence in agricultural systems, thereby increasing their effi ciency as biological control agents. Among the predatory insects, Coccinellidae (Coleoptera) on many different species both as larvae and adults, complementing their diet with pollen and/or nectar. This study aimed to determine the diversity and relative abundance of Coccinellidae species visiting plants of Anethum graveolens (dill), Coriandrum sativum (coriander) and Foeniculum vulgare (sweet fennel) (all Apiaceae), particularly in their blooming seasons, and to evaluate the potential of these aromatic species for providing the resources for survivorship and reproduction of coccinelids. Coccinellids were collected by removal of samplings from September to October, 2007. Besides one unidentifi ed species of Chilocorinae, five species of Coccinellinae were collected: Coleomegilla maculata DeGeer, Coleomegilla quadrifasciata (Schönherr), Cycloneda sanguinea (L.), Eriopis connexa (Germar) and Hippodamia convergens Guérin-Meneville. Dill provided a signifi cant increase in the abundance of coccinellids as compared to coriander and sweet fennel. These aromatic species were used by coccinellids as survival and reproduction sites, providing food resources (pollen and/or prey), shelter for larvae, pupae and adults, and mating and oviposition sites as well

Las interfaces entre apoyo social, calidad de vida y depresión en usuarios elegibles para cuidados paliativos

Objective: Analyzing the relationship between social support, quality of life and depression in patients eligible for palliative care at Primary Health Care of a municipality in the interior of Minas Gerais, Brazil. Method: A correlational cross-sectional study carried out with patients treated in six primary health care units. Data were submitted to descriptive statistical analysis, tests for differences between averages and medians, and correlation tests. The significance level was 0.05. Results: The sample consisted of 115 participants, and it was identified that the higher the social support, the better the global quality of life (p<0.001) and functional quality of life (p=0.035); the greater the presence of physical symptoms, the lower the level of social support (p=0.012) and the higher the level of depression (p<0.001); the higher the symptoms of depression, the worse the global quality of life (p<0.001), functional quality of life (p<0.001) and the lower the levels of social support (p<0.001). Conclusion: Levels of quality of life, social support and depression of patients eligible for palliative care are influenced by socioeconomic factors such as marital status, gender, age, income, education and presence of a caregiver.Objetivo: Analisar a relação entre apoio social, qualidade de vida e depressão em pacientes elegíveis para cuidados paliativos atendidos na Atenção Primária à Saúde de um município no interior de Minas Gerais, Brasil. Método: Estudo transversal correlacional, realizado com pacientes atendidos em seis unidades da atenção primária à saúde. Os dados foram submetidos à análise estatística descritiva, testes de diferenças entre médias e medianas e testes de correlação. O nível de significância adotado foi 0,05. Resultados: A amostra foi composta por 115 participantes, e identificou-se que quanto maior o apoio social, melhor é a qualidade de vida global (p<0,001) e funcional (p=0,035); quanto maior a presença de sintomas físicos, menor o nível de apoio social (p=0,012) e maior o nível de depressão (p<0,001); quanto maiores os sintomas de depressão, pior é a qualidade de vida global (p<0,001), funcional (p<0,001) e menores os níveis de apoio social (p<0,001). Conclusão: Os níveis de qualidade de vida, apoio social e depressão de pacientes elegíveis para cuidados paliativos são influenciados por fatores socioeconômicos, tais como estado conjugal, sexo, idade, renda, escolaridade e presença de cuidador.Objetivo: Analizar la relación entre apoyo social, calidad de vida y depresión en pacientes elegibles para cuidados paliativos atendidos en la Atención Primaria a la Salud de un municipio en el interior de Minas Gerais, Brasil. Método: Estudio transversal correlacional, realizado con pacientes atendidos en seis unidades de atención primaria a la salud. Los datos fueron sometidos al análisis estadístico descriptivo, pruebas de diferencias entre medias y medianas y pruebas de correlación. El nivel de significancia adoptado fue 0,05. Resultados: La muestra fue compuesta por 115 participantes, y se identificó que cuanto mayor el apoyo social, mejor es la calidad de vida global (p<0,001) y funcional (p=0,035); cuanto mayor sea la presencia de síntomas físicos, menor el nivel de apoyo social (p=0,012) y mayor el nivel de depresión (p<0,001); cuanto mayores los síntomas de depresión, peor es la calidad de vida global (p<0,001), funcional (p<0,001) y menores los niveles de apoyo social (p<0,001). Conclusión: Los niveles de calidad de vida, apoyo social y depresión de pacientes elegibles para cuidados paliativos son influenciados por factores socioeconómicos, tales como estado conyugal, sexo, edad, renta, escolaridad y presencia de cuidador

Palaeohistology and palaeopathology of an Aeolosaurini (Sauropoda: Titanosauria) from Morro do Cambambe (Upper Cretaceous, Brazil)

Altres ajuts: CAISEP (Comisión de Ayudas a la Investigación de la Sociedad Española de Paleontología) project #2018-07153A recent publication of fossil bones of titanosaurs assigned to Aeolosaurini from the Morro do Cambambe site (Mato Grosso state, Brazil, Upper Cretaceous) reported anomalous growth in some of them. Here, we present osteohistological sections of elements to understand not only the microstructure and growth of such bones, but also the nature of those anomalies. The primary bone of all specimens consisted of a variation of the fibrolamellar complex, with the inner cortex being rich in woven bone with dispersed longitudinal canals, while the outer cortex was parallel-fibred with rows of longitudinal canals, interlayered by Lines of Arrested Growth (LAGs). We identified a maximum of two LAGs in the cervical rib and haemal arch, and four in the dorsal rib. The haemal arch shows an External Fundamental System (EFS) in most sections. The advanced remodelling and variation of the fibrolamellar bone in the cortex suggests that all the specimens represent individuals that reached sexual maturity. However, the haemal arch was distinct due to the wide distribution of EFS. The dorsal rib exhibited periosteal and endosteal outgrowth. Such microstructure was assigned to a reactive bone due to an intra-thoracic infection (a pneumonia, probably related to a tuberculosis), which is the first report in a non-avian dinosaur. The microstructure resembles the medullary bone recovered in dinosaurs, which suggests that further studies of medullary bone in thoracic bones should also regard the pathological cases.En una reciente publicación de los huesos fósiles de titanosaurios asignados al clado Aeolosaurini provenientes del yacimiento de Morro do Cambambe (estado de Mato Grosso, Brasil, Cretácico Superior), se reconocieron anormalidades en el crecimiento de algunos de ellos. En el presente trabajo presentamos cortes osteohistológicos de elementos para entender no sólo la microestructura y crecimiento de los mismos, sino también la naturaleza de aquellas anomalías. Entre ellos, seleccionamos una costilla cervical y una costilla dorsal media posterior, así como un arco hemal. El hueso primario de todos los especímenes comprendía una variación del complejo fibrolamelar, siendo la corteza interna rica en tejido reticular óseo con canales longitudinales dispersos, mientras que la corteza externa tenía fibras paralelas con hileras de canales longitudinales, intercaladas por líneas de crecimiento detenido. Identificamos un máximo de dos líneas de crecimiento detenido tanto en la costilla cervical como en el arco hemal, y cuatro en la costilla dorsal. El arco hemal muestra un Sistema Externo Fundamental en la mayoría de las secciones. La remodelación avanzada y la variación del hueso fibrolamelar en la corteza, se sugiere que todas los especímenes alcanzaron la madurez sexual. Sin embargo, el arco hemal fue distinto debido a la amplia distribución de Sistema Externo Fundamental. Con base en la microestructura, identificamos un semaforonte subadulto, y probablemente a un adulto. La costilla dorsal mostró una excrecencia perióstica y endosteal. Dicha microestructura se ha identificado con un hueso reactivo a una infección intratorácica (una neumonía, probablemente relacionada con una tuberculosis), que es el primer informe de un dinosaurio no aviano. La microestructura se asemeja al hueso medular recuperado en los dinosaurios, lo que sugiere que los estudios posteriores del hueso medular en los huesos torácicos también deberían considerar los casos patológicos

Seroconversion in asymptomatic COVID-19 pediatric patients with rheumatic diseases of one tertiary referral hospital

Objectives: To evaluate seroconverted asymptomatic COVID-19 in pediatric Autoimmune Rheumatic Diseases (ARDs) patients and to identify the risk factors related to contagion. Methods: A cross-sectional study was conducted in March&nbsp;2021, before vaccination of children and adolescents in Brazil, including&nbsp;77&nbsp;pediatric ARDs patients, followed at a tertiary hospital and 45&nbsp;healthy controls, all of them without a previous diagnosis of COVID-19. Data was obtained by a questionnaire with demographic data, symptoms compatible with COVID-19 over the previous year, and contact with people with confirmed COVID-19. Patient's medical records were reviewed to access data regarding disease and current medications. A qualitative immunochromatographic SARS-CoV-2 test was performed on all participants. Results: Patients and controls were similar in terms of female gender (70.1%&nbsp;vs.&nbsp;57.8%, p&nbsp;=&nbsp;0.173), age (14&nbsp;vs.&nbsp;13 years, p&nbsp;=&nbsp;0.269) and SARS-CoV-2 positive serology (22%&nbsp;vs.&nbsp;15.5%, p&nbsp;=&nbsp;0.481). 80.5% of rheumatic patients were in use of immunosuppressive drugs:&nbsp;27.3% of them used corticosteroids (33.3%&nbsp;in high doses), and 7.8%&nbsp;on immunobiologicals. No statistical differences were found between positive (n&nbsp;=&nbsp;17) and negative serology (n&nbsp;=&nbsp;60) patients regarding demographic/socioeconomic data, contact with people with confirmed COVID-19, use and number of immunosuppressive drugs, use and dose of corticosteroids, use of hydroxychloroquine and immunobiological drugs (p &gt; 0.05). Conclusions: Pediatric rheumatic disease patients were infected at the same rate as healthy ones. Neither the underlying pathology nor its immunosuppressive treatment seemed to interfere with contagion risk

PEQUI: uma proposta de ensino de química para o ensino médio.

A química é uma ciência que se preocupa em entender o mundo, interage com a sociedade de diversas formas e está presente em nosso dia a dia. Diante disso, é importante mostrar aos alunos fenômenos do cotidiano, propiciando formas de inserir o estudante em seu ambiente cultural. Isso pode ser possível através da abordagem temática utilizando o pequi, acredita-se que o uso de um tema presente no dia a dia dos alunos facilita a assimilação de conceitos e estimula a aprendizagem. Diante desse pressuposto, o trabalho visou à elaboração de propostas de ensino de química para o ensino médio, buscando a sugestão de aulas contextualizadas. Para o desenvolvimento do trabalho foi feita uma investigação bibliográfica da composição química do pequi e suas propriedades terapêuticas, as quais foram relacionadas a conteúdos químicos. Observou-se que o pequi é uma ferramenta pra o ensino e aprendizado em química, tema pelo qual o professor poderá abordar para ensinar conteúdos desta ciência de forma contextualizada

Correction: optimized labeling of bone marrow mesenchymal cells with superparamagnetic iron oxide nanoparticles and in vivo visualization by magnetic resonance imaging

Abstract Background Stem cell therapy has emerged as a promising addition to traditional treatments for a number of diseases. However, harnessing the therapeutic potential of stem cells requires an understanding of their fate in vivo. Non-invasive cell tracking can provide knowledge about mechanisms responsible for functional improvement of host tissue. Superparamagnetic iron oxide nanoparticles (SPIONs) have been used to label and visualize various cell types with magnetic resonance imaging (MRI). In this study we performed experiments designed to investigate the biological properties, including proliferation, viability and differentiation capacity of mesenchymal cells (MSCs) labeled with clinically approved SPIONs. Results Rat and mouse MSCs were isolated, cultured, and incubated with dextran-covered SPIONs (ferumoxide) alone or with poly-L-lysine (PLL) or protamine chlorhydrate for 4 or 24 hrs. Labeling efficiency was evaluated by dextran immunocytochemistry and MRI. Cell proliferation and viability were evaluated in vitro with Ki67 immunocytochemistry and live/dead assays. Ferumoxide-labeled MSCs could be induced to differentiate to adipocytes, osteocytes and chondrocytes. We analyzed ferumoxide retention in MSCs with or without mitomycin C pretreatment. Approximately 95% MSCs were labeled when incubated with ferumoxide for 4 or 24 hrs in the presence of PLL or protamine, whereas labeling of MSCs incubated with ferumoxide alone was poor. Proliferative capacity was maintained in MSCs incubated with ferumoxide and PLL for 4 hrs, however, after 24 hrs it was reduced. MSCs incubated with ferumoxide and protamine were efficiently visualized by MRI; they maintained proliferation and viability for up to 7 days and remained competent to differentiate. After 21 days MSCs pretreated with mitomycin C still showed a large number of ferumoxide-labeled cells. Conclusions The efficient and long lasting uptake and retention of SPIONs by MSCs using a protocol employing ferumoxide and protamine may be applicable to patients, since both ferumoxides and protamine are approved for human use.</p

Evaluation antimicrobial and antiadhesive properties of the biosurfactant lunasan produced by Candida sphaerica UCP 0995

Abstract Different groups of biosurfactants exhibit diverse properties and display a variety of physiological functions in producer microorganisms; these include enhancing the solubility of hydrophobic/water-insoluble compound, heave metal binding, bacterial pathogenesis, cell adhesion and aggregation, quorum sensing and biofilm formation. Candida sphaerica was grown in a low cost medium, consisting of distilled water supplemented with 9% refinery residue of soybean oil and 9% corn steep liquor, for 144 h at 28°C and 150 rpm. The cell-free supernatant obtained at the end of the experiments was submitted to extraction, and afterward the biosurfactant was isolated using methanol with a yield of 9 g l -1 . The critical micelle concentration of the biosurfactant was found to be 0.25 mg ml -1 with a surface tension of 25 mN m -1 . Several concentrations of the biosurfactant (0.625-10 mg ml -1 ) were used to evaluate its antimicrobial and antiadhesive activities against a variety of microorganisms. The biosurfactant showed antimicrobial activity against Streptococcus oralis (68%), Candida albicans (57%), and Staphylococcus epidermidis(57.6%) for the highest concentration tested. Furthermore, the biosurfactant at a concentration of 10 mg ml -1 inhibited the adhesion between 80 and 92% of Pseudomonas aeruginosa, Streptococcus agalactiae, Streptococcus sanguis12. Inhibition of adhesion with percentages near 100% occurred for the higher concentrations of biosurfactant used. Results gathered in this study point to a potential use of the biosurfactant in biomedical applications