CO2 conversion to phenyl isocyanates by uranium(vi) bis(imido) complexes.

Uranium(vi) trans-bis(imido) complexes [U(κ4-{(tBu2ArO)2Me2-cyclam})(NPh)(NPhR)] react with CO2 to eliminate phenyl isocyanates and afford uranium(vi) trans-[O[double bond, length as m-dash]U[double bond, length as m-dash]NR]2+ complexes, including [U(κ4-{(tBu2ArO)2Me2-cyclam})(NPh)(O)] that was crystallographically characterized. DFT studies indicate that the reaction proceeds by endergonic formation of a cycloaddition intermediate; the secondary reaction to form a dioxo uranyl complex is both thermodynamically and kinetically hindered

Effectiveness of passive mobilization in the treatment of shoulder pathologies

Introdução: A dor no ombro é muito comum e o tratamento preferencial é a fisioterapia. Objectivo: Avaliar a efectividade da mobilização passiva na dor, força,amplitude de movimento e/ou função no tratamento de indivíduos com tendinopatias da coifa ou síndrome de colisão do ombro por meio de revisão sistemática de literatura. Métodos: Os estudos foram pesquisados na PubMed, Cochrane Library, Scielo, PEDro e Web of Science. Dois investigadores analisaram os artigos para determinar os trabalhos a incluir. A qualidade metodológica desses foi avaliada por meio da escala de PEDro e feita a sua caracterização detalhada. Resultados: Os resultados sugerem que a mobilização passiva quando aplicada em conjunto com outros tratamentos leva a significativa diminuição da dor e a melhoria da força e função. Conclusão: A mobilização passiva aplicada em conjunto com outros tratamentos parece ser uma mais valia no tratamento de tendinopatias da bainha rotadora e síndrome de colisão do ombro. São necessários mais estudos que confirmem esses resultados.Introduction: Pain in the shoulder is very common and the preferential treatment is physiotherapy. Objective: To assess the effectiveness of passive mobilization on pain, strength, range of motion and/or function for patients with rotator cuff tendinopathies or impingement syndrome. Methods: Studies were sought from PubMed, Cochrane Library, Scielo, PEDro and Web of Science. Two investigators screened all studies for inclusion. Methods: Quality was assessed using PEDro scale and a detailed characterization of each study was made. Results: All studies show that the group that received the treatment package including passive mobilization showed statistically significant decrease of pain and improvements for function and strength when compared to the control group. Conclusion: A trend was found favoring the addition of passive mobilization to a treatment package of physiotherapy for decreasing pain and increasing strength and function, but a firm conclusion cannot be made

Antimicrobial activity of Agave sisalana

This study was carried out to evaluate the antimicrobial activity of extracts of the leaves and leaf waste discarded in the process of obtaining the hard fibers of Agave sisalana. The antimicrobial activity was determined by the paper disk diffusion method using Gram-positive and Gram-negative bacteria (nonresistant and resistant to antibiotics) and a fungus. The hydroalcoholic extract obtained from leaves and from sisal waste showed significant inhibition of Candida albicans, on the other hand, it was inactive against three strains of Staphylococcus aureus, two strains of Escherichia coli, a strain ofMicrococcus luteus, Bacillus cereus, Pseudomonas aeruginosa and Salmonella choleraesuis. The methanol extract of leaves showed weaker reduction in the inhibitory action of C. albicans when compared with the above extracts, and it was also inert against the other microorganisms tested

O estudo do limite de uma função: o que disseram os alunos?

This article presents part of the results obtained in a doctoral research that had as objective to bring new reflections related to the concept of limit of a function. There are a large number of research works with different approaches and methodologies that seek to discover the reasons for the widespread failure of students in the discipline of Differential and Integral Calculus. But there are still few who work on the college student's look at this difficulty. We will present in this text, specifically, the data of the students regarding the concept of limit with the hope that they can sensitize the teachers who teach this discipline.Este artículo presenta parte de los resultados obtenidos en una investigación de doctorado que tuvo como objetivo traer nuevas reflexiones relacionadas al concepto de límite de una función. Hay un número grande de trabajos de investigación con diferentes enfoques y metodologías que buscaron descubrir los motivos para el fracaso generalizado de los alumnos en la disciplina de Cálculo Diferencial e Integral. Pero todavía hay pocos que trabajan sobre la mirada del alumno universitario sobre esta dificultad. Presentaremos en este texto, específicamente, los datos de los alumnos referentes al concepto de límite con la esperanza de que los mismos puedan sensibilizar a los profesores que enseñan esa disciplina. Cet article présente une partie des résultats obtenus dans une recherche doctorale ayant pour objectif d'apporter de nouvelles réflexions liées au concept de limite d'une fonction. Il existe un grand nombre de travaux de recherche avec différentes approches et méthodologies qui cherchent à découvrir les raisons de l'échec généralisé des étudiants dans la discipline du calcul différentiel et intégral. Cependant il y en a encore peu qui travaillent sur le regard de l'étudiant sur cette difficulté. Nous présenterons dans ce texte, en particulier, les données des étudiants concernant le concept limite avec l'espoir qu'ils puissent sensibiliser les enseignants qui enseignent cette discipline.Este artigo apresenta parte dos resultados obtidos em uma pesquisa de doutorado que teve como objetivo trazer novas reflexões relacionadas ao conceito de limite de uma função. Há um número grande de trabalhos de investigação com diferentes abordagens e metodologias que procuraram descobrir os motivos para o fracasso generalizado dos alunos na disciplina de Cálculo Diferencial e Integral. Mas, há ainda poucos trabalham que versam sobre o olhar do aluno universitário sobre essa dificuldade. Apresentaremos nesse texto, especificamente, os dados dos alunos referentes ao conceito de limite com a esperança de que os mesmos possam sensibilizar os professores que ensinam essa disciplina

O QUE PENSAM OS PROFESSORES UNIVERSITÁRIOS SOBRE O ENSINO E A APRENDIZAGEM DO CONCEITO DE LIMITE?

Este artigo apresenta parte dos resultados obtidos em uma pesquisa de doutorado que teve como objetivo trazer novas reflexões relacionadas ao conceito de limite de uma função. Há um número grande de trabalhos de investigação com diferentes abordagens e metodologias que procuraram descobrir os motivos para o fracasso generalizado dos alunos na disciplina de Cálculo Diferencial e Integral. Mas, há ainda poucos trabalham que versam sobre o olhar do professor universitário sobre essa dificuldade. Apresentaremos nesse texto, especificamente, as “falas” deprofessores universitários referentes ao conceito de limite e seu ensino. Para tanto, procuraremos inicialmente explicitar como realizamos a leitura dessas falas. O método utilizado para a análise se aproxima da análise de conteúdo porque fizemos uma leitura repetida das respostas até encontrarmos uma maneira de explicitar o que era comum ou não, o que se repetia com frequência, as palavras mais utilizadas. Ao falarem da definição formal de limite, alguns professores utilizaram os termos vizinhança, aproximações, e mencionaram trabalhar com mais de um registro em sala de aula. Na nossa perspectiva, essa explicação não se constitui verdadeiramente em uma explicação, mas em uma “leitura” da mesma. E, então, nos perguntamos: Que visão o professor universitário teria de explicação? Como seria para ele traduzir/decodificar o simbólico para o aluno

CYP2C19 and ABCB1 gene polymorphisms are differently distributed according to ethnicity in the Brazilian general population

<p>Abstract</p> <p>Background</p> <p>Recent studies have reported the clinical importance of <it>CYP2C19 </it>and <it>ABCB1 </it>polymorphisms in an individualized approach to clopidogrel treatment. The aims of this study were to evaluate the frequencies of <it>CYP2C19 </it>and <it>ABCB1 </it>polymorphisms and to identify the clopidogrel-predicted metabolic phenotypes according to ethnic groups in a sample of individuals representative of a highly admixtured population.</p> <p>Methods</p> <p>One hundred and eighty-three Amerindians and 1,029 subjects of the general population of 4 regions of the country were included. Genotypes for the <it>ABCB1</it>c.C3435T (rs1045642), <it>CYP2C19*2 </it>(rs4244285), <it>CYP2C19*3 </it>(rs4986893), <it>CYP2C19*4 </it>(rs28399504), <it>CYP2C19*5 </it>(rs56337013), and <it>CYP2C19*17 </it>(rs12248560) polymorphisms were detected by polymerase chain reaction followed by high resolution melting analysis. The <it>CYP2C19*3</it>, <it>CYP2C19*4 </it>and <it>CYP2C19*5 </it>variants were genotyped in a subsample of subjects (300 samples randomly selected).</p> <p>Results</p> <p>The <it>CYP2C19*3 </it>and <it>CYP2C19*5 </it>variant alleles were not detected and the <it>CYP2C19*4 </it>variant allele presented a frequency of 0.3%. The allelic frequencies for the <it>ABCB1</it>c.C3435T, <it>CYP2C19*2 </it>and <it>CYP2C19*17 </it>polymorphisms were differently distributed according to ethnicity: Amerindian (51.4%, 10.4%, 15.8%); Caucasian descent (43.2%, 16.9%, 18.0%); Mulatto (35.9%, 16.5%, 21.3%); and African descent (32.8%, 20.2%, 26.3%) individuals, respectively. As a result, self-referred ethnicity was able to predict significantly different clopidogrel-predicted metabolic phenotypes prevalence even for a highly admixtured population.</p> <p>Conclusion</p> <p>Our findings indicate the existence of inter-ethnic differences in the <it>ABCB1 </it>and <it>CYP2C19 </it>variant allele frequencies in the Brazilian general population plus Amerindians. This information could help in stratifying individuals from this population regarding clopidogrel-predicted metabolic phenotypes and design more cost-effective programs towards individualization of clopidogrel therapy.</p

Transcription factor NRF2 protects mice against dietary iron-induced liver injury by preventing hepatocytic cell death

BACKGROUND & AIMS: The liver, being the major site of iron storage, is particularly exposed to the toxic effects of iron. Transcription factor NRF2 is critical for protecting the liver against disease by activating the transcription of genes encoding detoxification/antioxidant enzymes. We aimed to determine if the NRF2 pathway plays a significant role in the protection against hepatic iron overload.METHODS: Wild-type and Nrf2(-/-) mouse primary hepatocytes were incubated with ferric ammonium citrate. Wild-type and Nrf2(-/-) mice were fed standard rodent chow or iron-rich diet for 2weeks, with or without daily injection of the antioxidant mito-TEMPOL.RESULTS: In mouse hepatocytes, iron induced the nuclear translocation of NRF2 and the expression of cytoprotective genes in an NRF2-dependent manner. Moreover, Nrf2(-/-) hepatocytes were highly susceptible to iron-induced cell death. Wild-type and Nrf2(-/-) mice fed iron-rich diet accumulated similar amounts of iron in the liver and were equally able to increase the expression of hepatic hepcidin and ferritin. Nevertheless, in Nrf2-null mice the iron loading resulted in progressive liver injury, ranging from mild confluent necrosis to severe necroinflammatory lesions. Hepatocytic cell death was associated with gross ultrastructural damage to the mitochondria. Notably, liver injury was prevented in iron-fed animals that received mito-TEMPOL.CONCLUSIONS: NRF2 protects the mouse liver against the toxicity of dietary iron overload by preventing hepatocytic cell death. We identify NRF2 as a potential modifier of liver disease in iron overload pathology and show the beneficial effect of the antioxidant mito-TEMPOL in a mouse model of dietary iron-induced liver injury.This work is funded by FEDER Funds through the Operational Competitiveness Programme - COMPETE and by National Funds through FCT - Fundacao para a Ciencia e a Tecnologia under the project FCOMP-01-0124-FEDER-011062 (PTDC/SAU-FCF/101177/2008). TLD is supported by "Programa Ciencia - financiado pelo POPH - QREN - Tipologia 4.2 - Promocao do Emprego Cientifico, comparticipado pelo Fundo Social Europeu e por fundos nacionais do MCTES''