Conceptions on protein, sugar and fats : an investigation with students of basic and higher education

A Bioquímica, enquanto campo do conhecimento busca entender os processos químicos que ocorrem nos sistemas biológicos, sendo assim, é de fundamental importância para o entendimento de nossa própria existência. Apesar de ser uma ciência com conceitos muito bem estruturados, fora do ambiente acadêmico encontramos muitos conhecimentos baseados em senso comum, as chamadas concepções alternativas. Por carregarem uma grande conotação simplista como forma de explicar os fenômenos ou preceitos científicos, tais concepções podem se tornar obstáculos para uma aprendizagem significativa. Dessa forma, é necessário que o professor tome conhecimento de tais concepções para que possa repensar a sua prática, (re) construindo-a de acordo com as necessidades de seus estudantes. Nesse sentido, o presente trabalho visa, por meio de um questionário, inventariar as concepções de estudantes de escolas públicas da cidade de Santa Maria, RS. Foram investigados 34 estudantes de Ensino Fundamental (nono ano), 306 de Ensino Médio (1º, 2º e 3º anos) e 36 de Ensino Superior (formandos do Curso de Licenciatura em Química da Universidade Federal de Santa Maria – RS) sobre os conceitos: Proteínas, Açúcares e Gorduras. De modo geral, podemos perceber nas respostas uma grande tendência em considerar as proteínas como substâncias fundamentais para a saúde, muito relacionadas à “energia” e “força”. Por outro lado, açúcares e gorduras, são considerados substâncias ruins e causadoras de doenças e problemas estéticos, o que não deixa de ser verdade, porém, pode indicar que estes estudantes não têm um claro entendimento do papel de tais substâncias para o correto funcionamento e manutenção dos organismos.Biochemistry, as a field of knowledge seeks to understand the chemical processes that occur in biological systems, it is therefore of fundamental importance for the understanding of our own existence. Despite being a science with well structured concepts, outside the academic environment we find many knowledge based on common sense, the so-called alternative conceptions. On carry a large connotation as simplistic way of explaining the phenomena or scientific principles, these concepts may become obstacles to meaningful learning. Thus, it is necessary that the teacher becomes aware of such concepts to help you rethink your practice, (re) building it according to the needs of their students. In this sense, the present work aims, using a questionnaire, survey the conceptions of students from public schools in the city of Santa Maria, RS. Thirty four students from Elementary School (ninth year), 306 of Secondary Education (1st, 2nd and 3rd years) and 36 of Higher Education (Chemistry Licentiate students, from Federal University of Santa Maria - RS) were investigated on the concepts: proteins, sugars and fats. Overall, we can see a big trend in the responses to consider the proteins as key substances for health, closely related to the "energy" and "force." On the other hand, sugars and fats are considered bad substances and disease-causing and esthetic problems, which is nonetheless true, however, may indicate that these students have no a clear understanding of the role of such substances for proper operation and maintenance of organisms

Modulatory effect of diphenyl diselenide in Carioca High- and Low-conditioned Freezing rats

AbstractDiphenyl diselenide ([PhSe]2)is an organoselenium compound that has interesting pharmacological properties, including antioxidant, glutathione peroxidase-mimetic, and neuroprotective effects. The objective of the present study was to investigate the possible modulatory effect of (PhSe)2 in 17th-generation Carioca high-and low-conditioned freezing (CHF and CLF) rats, an animal model of generalized anxiety disorders. (PhSe)2 was administered at three doses (10, 50, and 100mg/kg) in CHF and CLF rats, and their anxiety-like profiles (conditioned freezing patterns) were measured before and 30min after treatment. A significant difference was found in freezing scores between CHF and CLF animals before treatment (t70=12.50, p<0.001). Treatment with (PhSe)2 at 10 and 50mg/kg decreased freezing in CHF rats but significantly increased freezing at 100mg/kg. (PhSe)2 increased freezing in CLF animals at 50 and 100mg/kg (p<0.01). These results indicate that (PhSe)2 exerts both anxiolytic- and anxiogenic-like effects in bi-directional rat lines. Distinct genetic profiles of the CHF and CLF lines may influence biochemical functions and lead to differential responses to aversive situations and various drugs like (PhSe)2

Efeito in vivo e in vitro do HgCl2 e do 2,3-dimercaprol (BAL) sobre a atividade da ALA-D de cérebro, fígado e rim de camundongos adultos

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Mudança no uso e ocupação do solo na bacia hidrográfica do rio Uruçuí-Preto, Piauí/ Change on land use in the watershed of Uruçuí–Preto river, Piauí, Brazil

 A ocupação dos ecossistemas para o desenvolvimento da agropecuária vem se intensificando, tornando assim um motivo de grande preocupação no que se refere ao desmatamento e ocupação das regiões de Cerrado. Assim, objetivou-se com este trabalho identificar a alteração do uso e ocupação do solo entre os anos 1984 a 2007 na bacia hidrográfica do rio Uruçuí-Preto, Piauí. A bacia do rio Uruçuí-Preto apresenta área de 15.777 km2. Foram utilizadas imagens do Satélite Landsat 5 sensor TM (Thematic Mapper) no período de 1984 a 2007. Inicialmente fez-se o pré-processamento das imagens, correção geométrica e de contraste das imagens. Após correção fez- a classificação das imagens, a análise foi realizada por meio da classificação automática supervisionada utilizando o algoritmo de máxima verossimilhança. As classes atribuídas as fisionomias de interesse foram Cerrado, Solo Exposto/Talhão Agrícola, Queimada e Mata Ciliar. Com base nos resultados apresentados houve variações em todas as classes de uso e ocupação do solo ao decorrer do período analisado.  Ao se comparar os anos de 1984 e 2007, a classe Cerrado apresentou redução de 20,9% (3.332,96 km2), a classe Solo Exposto/Talhão Agrícola apresentou aumento de 13,48% (2.149,17 km2), a classe Mata Ciliar apresenta grande oscilação durante o período analisado, devido a dinâmica da vegetação, apresentando redução de 2,4% (383,46 km2) e a classe Queimada apresentou dois anos com grandes áreas, 1990 (2.280,47 km2) e 2007 (1.567,24 km2). Percebe-se então a substituição da cobertura de vegetação nativa por áreas destinadas as atividades agrícolas

Cellulolytic and proteolytic ability of bacteria isolated from gastrointestinal tract and composting of a hippopotamus

The bioprospection for cellulase and protease producers is a promise strategy for the discovery of potential biocatalysts for use in hydrolysis of lignocellulosic materials as well as proteic residues. These enzymes can increment and turn viable the production of second generation ethanol from different and alternative sources. In this context, the goal of this study was the investigation of cellulolytic and proteolytic abilities of bacteria isolated from the gastrointestinal tract of a hippopotamus as well as from its composting process. It is important to highlight that hippopotamus gastrointestinal samples were a non-typical sources of efficient hydrolytic bacteria with potential for application in biotechnological industries, like biofuel production. Looking for this, a total of 159 bacteria were isolated, which were submitted to qualitative and quantitative enzymatic assays. Proteolytic analyzes were conducted through the evaluation of fluorescent probes. Qualitative assays for cellulolytic abilities revealed 70 positive hits. After quantitative analyzes, 44 % of these positive hits were selected, but five (5) strains showed cellulolytic activity up to 11,8 FPU/mL. Regarding to proteolytic activities, six (6) strains showed activity above 10 %, which overpassed results described in the literature. Molecular analyzes based on the identification of 16S rDNA, revealed that all the selected bacterial isolates were affiliated to Bacillus genus. In summary, these results strongly indicate that the isolated bacteria from a hippopotamus can be a potential source of interesting biocatalysts with cellulolytic and proteolytic activities, with relevance for industrial applications.Brazilian research agency (FAPESP)Brazilian research agency (CAPES)Brazilian research agency (CNPq)Univ Fed Sao Paulo, Dept Biol Sci, Rua Sao Nicolau 210, BR-09913030 Sao Paulo, BrazilSao Paulo Zoo Pk Fdn, Av Miguel Estefano 4241, BR-04301905 Sao Paulo, SP, BrazilUniv Fed Sao Paulo, Dept Biophys, Rua 3 Maio,100, BR-04044020 Sao Paulo, SP, BrazilFed Univ Latin Amer Integrat, Latin Amer Inst Life Sci & Nat, Av Tarquinio Joslin Santos 1000, BR-85870901 Foz Do Iguacu, Parana, BrazilUniv Fed Sao Paulo, Dept Biol Sci, Rua Sao Nicolau 210, BR-09913030 Sao Paulo, BrazilUniv Fed Sao Paulo, Dept Biophys, Rua 3 Maio,100, BR-04044020 Sao Paulo, SP, BrazilFAPESP: 2010/51992-5CNPq: 475166/2013-2Web of Scienc

Brain zinc chelation by diethyldithiocarbamate increased the behavioral and mitochondrial damages in zebrafish subjected to hypoxia

The increase in brain levels of chelatable zinc (Zn) in dysfunctions involving oxygen deprivation has stimulated the treatment with Zn chelators, such as diethyldithiocarbamate (DEDTC). However, DEDTC is a redox-active compound and it should be better evaluated during hypoxia. We use the hypoxia model in zebrafish to evaluate DEDTC effects. The exploratory behavior, chelatable Zn content, activities of mitochondrial dehydrogenases, reactive species levels (nitric oxide, superoxide anion, hydroxyl radical scavenger capacity) and cellular antioxidants (sulfhydryl, superoxide dismutase) of zebrafish brain were assessed after recovery, with or without 0.2mM DEDTC. The increased brain levels of chelatable Zn induced by hypoxia were mitigated by DEDTC. However, the novel tank task indicated that DEDTC did further enhance the exploratory deficit caused by hypoxia. Furthermore, these behavioral impairments caused by DEDTC were more associated with a negative action on mitochondrial activity and brain oxidative balance. Thus, due to apparent pro-oxidant action of DEDTC, our data do not support its use for neuroprotection in neuropathologies involving oxygen deprivation

Editorial: 10 years of Frontiers in genetics: past discoveries, current challenges and future perspectives

3 páginasThis research was supported by the National Institute on Health,grant number R01AG059586, R01AG059586-03S1, and by the University of Connecticut (UConn) Claude D. Pepper Older Americans Independence Center (P30-AG067988). BR is a recipient of a Glenn Award for Research in Biological Mechanisms of Aging. Research in the MR lab is supported by the Canadian Institutes of Health Research (CIHR) Project Grant 202203PJG-482520-CIA-CDAA-111824, CIHR Project Grant 202209PJT-486512-CIA-CDAA-111824, University of Manitoba Collaborative Research Program, Ontario Rett Syndrome Association Hope Fund, Children Hospital Research Institute of Manitoba (CHRIM), and Natural Sciences and Engineering Research Council of Canada (NSERC) Discovery Grant RGPIN2016-06035. Work at JP-T’s lab was supported by CIBER-Consorcio Centro de Investigación Biomédica en Red-(209), Instituto de Salud Carlos III, Ministerio de Ciencia e Innovación.Peer reviewe

Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection