Instructional materials in a STSE perspective: an analisys of units produced by secondary chemistry teachers in continuant formation

Some research has shown that teachers present conceptions that indicate a vision of teaching focused on memorization and transmission of knowledge and do not consider an approach that regards to the STSE aspects. The aim of this study is to investigate the conceptions of contextualization present in instructional materials produced by a group of chemistry secondary teachers. The data were collected in a service course offered to teachers of São Paulo Metropolitan area. One of the strategies of the course was the production of instructional units based on STSE (Science, Technology, Society and Environment) orientations. The data analysis takes into account: presence of problematization, its development throughout the unit; the relations established between experiments or text and the proposed theme, and the nature of information presented in the texts (scientific, social, technological, environmental). Four context profiles were built to characterize the 13 units elaborated by the teachers. Four of the teachers’ units revealed simple contextualization view profiles, although six of them revealed more complex profiles, compatible with STSE orientation

Antimicrobial activity of Alternanthera brasiliana Kuntze (Amaranthaceae): a biomonitored study

In an attempt to identify new antimicrobial compounds with potential to be used as a bactericidal/ fungicidal agent, a biomonitored study of extracts of Alternanthera brasiliana, which is used in Brazilian folk medicine as bactericidal, analgesic and anti-inflammatory, was developed. Different techniques of evaluation have been used in the partitioned extracts of the antimicrobial activity associated with chromatographic methodologies. The work led to the isolation of two substances in the ethyl acetate extract, identified as quercetin and sitosterol glycoside and the antibacterial evaluation of these substances demonstrated that the flavonoid presented antibacterial action against S. aureus. Further studies intend to identify new substances with antibacterial activity in extracts of A. brasiliana.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Ilex paraguariensis extracts extend the lifespan of Drosophila melanogaster fed a high-fat diet

Studies have suggested that total energy intake and diet composition affect lifespan and ageing. A high-fat diet induces oxidative stress and affects the development of diseases. In contrast, antioxidants are capable of reducing its harmful effects. Yerba mate beverages are an important source of antioxidants, but there is scarce knowledge about their effects on suppressing fat accumulation. Here, we investigated the compounds present in yerba mate extracts and assessed their effects on Drosophila melanogaster given a high cholesterol diet. LS-ESI-MS analysis showed the presence of matesaponins, phenolic compounds and methylxanthines in all of the examined extracts. In Drosophila, under extract treatment conditions, the mean lifespan was significantly extended from 38 to 43 days, there was an increase in the ability to support induced stress and decrease in lipid peroxidation products. Moreover, yerba mate extracts recovered the glutathione S-transferases (GST) activity and reduced the cholesterol level. Taken together, our results support that extracts can extend lifespan by reducing the detrimental effect of a high-fat diet in D. melanogaster, and this outcome can be associated with the compound content in the extracts. This study improves the understanding of natural interventions that reduce stress-induced oxidative damage, which is fundamental in promoting healthy ageing

Synthesis and antiproliferative activity of novel limonene derivatives with a substituted thiourea moiety

A series of R-(+)-limonene derivatives bearing a substituted thiourea moiety (3-13) and five S-methyl analogs (14-18) were synthesized and evaluated for their in vitro antiproliferative activity against human cancer cell lines. Compounds bearing aromatic substituents (3-6) exhibit cytotastic activity in the full panel of cell lines tested, with GI50 values in the range of 2.5 to 24 µmol L-1. Compounds 3, 10, 12 and 16 were the most active with GI50 values in the range of 0.41 to 3.0 µmol L-1, against different cell lines.No presente trabalho descrevemos a síntese e a avaliação da atividade antiproliferativa, frente a linhagens de células tumorais humanas, de derivados do R-(+)-limoneno (3-18) contendo uma unidade tiouréia substituída. Os derivados com substituintes arílicos (3-6) exibiram atividade citostática frente a todas linhagens testadas, com inibição de 50% do crescimento celular (GI50) em concentrações na faixa de 2,5 a 24 µmol L-1. Os compostos 3, 10, 12 e 16 foram os mais ativos, com GI50 na faixa de 0,41 a 3,0 mmol L-1, frente a diferentes linhagens celulares.954960Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Detection and Quantification of Leptospira interrogans in Hamster and Rat Kidney Samples: Immunofluorescent Imprints versus Real-time PCR

A major limitation in the clinical management and experimental research of leptospirosis is the poor performance of the available methods for the direct detection of leptospires. In this study, we compared real-time PCR (qPCR), targeting the lipL32 gene, with the immunofluorescent imprint method (IM) for the detection and quantification of leptospires in kidney samples from the rat and hamster experimental models of leptospirosis. Using a virulent strain of Leptospira interrogans serovar Copenhageni, a chronic infection was established in the rat model, which were euthanized 28 days post-infection, while the hamster model simulated an acute infection and the hamsters were euthanized eight days after inoculation. Leptospires in the kidney samples were detected using culture isolation, qPCR and the IM, and quantified using qPCR and the IM. In both the acute and chronic infection models, the correlation between quantification by qPCR and the IM was found to be positive and statistically significant (P<0.05). Therefore, this study demonstrates that the IM is a viable alternative for not only the detection but also the quantification of leptospires, particularly when the use of qPCR is not feasible

Aplicação da biologia molecular no diagnóstico de doenças genéticas

With the advances of the so called Genomic Medicine, the molecular analysis of genetic diseases increased the needs of a full characterization of alterations shown by an individual and is becoming essential for a differential diagnosis in several cases. The purpose of the present paper is to describe the molecular diagnostic protocols used in the Molecular Genetics Laboratory of the Medical Genetics Service of the Hospital de Clínicas of Porto Alegre. Most of these protocols are aimed at the use of updated and specialized molecular biology techniques in Brazil. The objective is not only the characterization of the affected patient’s genotype, but also the improvement of genetic counseling through the use of more sensitive and trustable techniques and strategies for the detection of carriers and for prenatal diagnosis in future pregnancies.Com os avanços da chamada Medicina Genômica, a análise molecular de doenças genéticas vem sendo cada vez mais necessária para a completa caracterização das alterações apresentadas por um indivíduo ou até mesmo essencial para um diagnóstico diferencial em muitos casos. O objetivo deste artigo é descrever os protocolos de diagnóstico molecular utilizados no laboratório de genética molecular do Serviço de Genética Médica do Hospital de Clínicas de Porto Alegre, que visam, em sua maioria, a utilização de técnicas atualizadas e especializadas de biologia molecular no Brasil, para permitir não apenas a caracterização do genótipo dos pacientes afetados mas também para melhorar o aconselhamento genético através do uso de técnicas e estratégias mais sensíveis e mais confiáveis para a detecção de portadores e para o diagnóstico pré-natal em gestações futuras

Anatomical Organization of Urocortin 3-Synthesizing Neurons and Immunoreactive Terminals in the Central Nervous System of Non-Human Primates [Sapajus spp.]

Urocortin 3 (UCN3) is a neuropeptide member of the corticotropin-releasing factor (CRF) peptide family that acts as a selective endogenous ligand for the CRF, subtype 2 (CRF2) receptor. Immunohistochemistry and in situ hybridization data from rodents revealed UCN3-containing neurons in discrete regions of the central nervous system (CNS), such as the medial preoptic nucleus, the rostral perifornical area (PFA), the medial nucleus of the amygdala and the superior paraolivary nucleus. UCN3-immunoreactive (UCN3-ir) terminals are distributed throughout regions that mostly overlap with regions of CRF2 messenger RNA (mRNA) expression. Currently, no similar mapping exists for non-human primates. To better understand the role of this neuropeptide, we aimed to study the UCN3 distribution in the brains of New World monkeys of the Sapajus genus. To this end, we analyzed the gene and peptide sequences in these animals and performed immunohistochemistry and in situ hybridization to identify UCN3 synthesis sites and to determine the distribution of UCN3-ir terminals. The sequencing of the Sapajus spp. UCN3-coding gene revealed 88% and 65% identity to the human and rat counterparts, respectively. Additionally, using a probe generated from monkey cDNA and an antiserum raised against human UCN3, we found that labeled cells are mainly located in the hypothalamic and limbic regions. UCN3-ir axons and terminals are primarily distributed in the ventromedial hypothalamic nucleus (VMH) and the lateral septal nucleus (LS). Our results demonstrate that UCN3-producing neurons in the CNS of monkeys are phylogenetically conserved compared to those of the rodent brain, that the distribution of fibers agrees with the distribution of CRF2 in other primates and that there is anatomical evidence for the participation of UCN3 in neuroendocrine control in primates

Release of NO from a nitrosyl ruthenium complex through oxidation of mitochondrial NADH and effects on mitochondria

Nitrosyl ruthenium complexes are promising NO donor agents with numerous advantages for the biologic applications of NO. We have characterized the NO release from the nitrosyl ruthenium complex [Ru(NO2)(bpy)(2)(4-pic)](+) (I) and the reactive oxygen/nitrogen species (ROS/RNS)-mediated NO actions on isolated rat liver mitochondria. The results indicated that oxidation of mitochondrial NADH promotes NO release from (I) in a manner mediated by NO2 formation (at neutral pH) as in mammalian cells, followed by an oxygen atom transfer mechanism (OAT). The NO released from (I) uncoupled mitochondria at low concentrations/incubation times and inhibited the respiratory chain at high concentrations/incubation times. In the presence of ROS generated by mitochondria NO gave rise to peroxynitrite, which, in turn, inhibited the respiratory chain and oxidized membrane protein-thiols to elicit a Ca2+-independent mitochondrial permeability transition; this process was only partially inhibited by cyclosporine-A, almost fully inhibited by the thiol reagent N-ethylmaleimide (NEM) and fully inhibited by the NO scavenger 2-(4-carboxyphenyl)-4,45,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO). These actions correlated with the release of cytochrome c from isolated mitochondria as detected by Western blotting analysis. These events, typically involved in cell necrosis and/or apoptosis denote a potential specific action of (I) and analogs against tumor cells via mitochondria-mediated processes. (C) 2012 Elsevier Inc. All rights reserved.FAPESPCNP