Efeitos da administração aguda de vitamina C na reatividade vascular arterial e venosa em tabagistas

Orientador: Heitor Moreno JuniorDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias MedicasResumo: Fumar é o mais importante fator de risco modificável para aterosclerose. O tabagismo está fortemente ligado a disfunção endotelial. Tem sido sugerido que a disfunção endotelial possa ser conseqüência do aumento da degradação do óxido nítrico secundária a formação de radicais livres derivados do oxigênio. O cigarro contém uma grande quantidade destes radicais livres e hipóteses têm sido levantadas sobre seus efeitos adversos resultantes do dano oxidativo a substâncias biológicas, dentre estas, o óxido nítrico. A vitamina C é o mais potente antioxidante solúvel em água no plasma humano, sendo capaz de retirar uma grande variedade de espécies reativas de nitrogênio e oxigênio, incluindo radicais superóxido. Alguns estudos têm demonstrado melhora da resposta dependente do endotélio no leito arterial de tabagistas com infusão aguda de vitamina C. Há uma significante heterogeneidade da função endotelial dentro da circulação. Desde que veias não são susceptíveis à aterosclerose, no presente estudo, investigamos o efeito da infusão aguda de vitamina C no leito venoso através da técnica da veia dorsal da mão (TVDM) e no leito arterial através da dilatação mediada pelo fluxo (FMD), permitindo, assim, a comparação de ambos os territórios endoteliais. Estudamos 6 não fumantes sadios e 7 fumantes moderados sadios através da técnica da complacência da veia dorsal da mão e vasodilatação mediada pelo fluxo. Curvas doses-resposta à bradicinina (BK) e nitroprussiato de sódio (NPS) foram construídas para testar o relaxamento dependente e não-dependente do endotélio venoso antes e após a infusão aguda de vitamina C. Pressão arterial, freqüência cardíaca, resistência vascular sistêmica e débito cardíaco foram medidos batimento a batimento durante todo o estudo através do portapres, um método contínuo de aferição de pressão arterial digital não-invasivo. Os tabagistas moderados apresentaram uma resposta vascular dependente do endotélio reduzida em ambos os leitos vasculares quando comparados a indivíduos não tabagistas (venoso Emax = 71,2 ? 17,3% vs 95,7 ? 21,2% e arterial 8,5 ± 3,7% vs 16,2 ± 2,7%; p<0,05). A administração aguda de vitamina C restaurou similarmente a responsividade vascular dependente do endotélio no leito venoso (Emax = 71,2 ? 17,3% e 88,3 ? 7,0%; respectivamente antes e após sua administração; p<0,05) e arterial (8,5 ? 3,7% e 17,7 ? 7,7%; respectivamente antes e após sua administração; p<0,05) em tabagistas moderados. A responsividade não-dependente do endotélio foi inalterada entre os grupos estudadosAbstract: Background: Chronic smoking is associated with endothelial dysfunction. Vitamin c, an antioxidant, improves the endothelium-mediated vasodilatation in arteries in smokers. There is significant heterogeneity of endothelial function within the circulation. Since veins are generally not susceptible to atherosclerosis, this model allows comparable assessment of changes in endothelial function between both territories. Methods and Results: We studied 06 healthy non-smokers and 07 healthy moderate smokers with the dorsal hand vein compliance technique and the flow mediated dilation. Dose response curves to bradykinin (BK) and sodium nitroprusside (SNP) were constructed to test the endothelium-dependent and non-dependent relaxation before and after acute infusion of vitamin C (25mg/min). Smokers had an impaired vasodilatation to bradykinin compared to non-smokers (Emax = 95,7 ? 21,2% vs 71,2 ? 17,3%; respectively, p<0,05). Vitamin C administration in dorsal hand vein significantly increased the vasodilatation to bradykinin in smokers (Emax = 71,2 ? 17,3% vs 88,3 ? 7,0%; p<0,05) but not in non-smokers (Emax = 95,7 ? 21,2% vs 82,7 ? 4,1%; non significant). Similarly, the arterial response in smokers had an impaired endothelium-dependent dilatation compared to non-smokers (16,2 ± 2,7% vs 8,5 ± 3,7%; respectively, p<0,05) and vitamin C restored this response in smokers (8,5 ± 3,7% vs 17,7 ± 7,7%; p<0,05) but not in non-smokers (16,2 ± 2,7% vs 14,4 ± 4,1%; non significant). The endothelium non-dependent dilatation did not differ in the studied groups. Conclusions: Smokers had similar impaired endothelium-dependent vasodilatation responsiveness in both vascular beds. Vitamin c restores the impaired endothelium-dependent responsiveness in smokersMestradoMestre em Clinica Medic

Resistance of Rice Varieties to \u3ci\u3eSitophilus oryzae\u3c/i\u3e (Coleoptera: Curculionidae)

Abstract Rice, Oryza sativa L. (Poaceae), is one of the world’s most important food crops. Among the insects that damage rice grains, the rice weevil, Sitophilus oryzae (L.) (Coleoptera: Curculionidae), is the most important species. The objective of this study was to identify rice varieties with resistance to S. oryzae as measured by grain feeding damage and S. oryzae reproduction. The rice varieties evaluated were obtained from the germplasm bank of the National Center of Research Rice and Beans, Embrapa, Brazil. The experimental design was completely randomized with 3 replications and 22 treatments (varieties). The varieties Bonança, Esmeralda, and Rio Verde had the antibiosis and/or antixenosis type of resistance, providing high rates of mortality, low rates of adult emergence, and low rates of grain consumption by S. oryzae. The varieties Pepita and Progresso were susceptible, with a high rate of S. oryzae adult emergence and grain consumption. The presence or absence of a fissure in the grain was a major morphological characteristic determining susceptibility or resistance to S. oryzae in rice varieties. Resumo O arroz (Oryza sativa L.; Poaceae) é uma das culturas alimentares mais importantes do mundo. Entre os insetos que danificam os grãos de arroz, o gorgulho do arroz Sitophylus oryzae L. (Coleoptera: Curculionidae) é a espécia mais importante. O objetivo deste trabalho foi identificar variedades de arroz com resistência a S. oryzae. As variedades de arroz avaliadas foram obtidas do banco de germoplasma do Centro Nacional de Pesquisas em Arroz e Feijão, EMBRAPA, Brasil. O delineamento experimental foi inteiramente casualizado com 3 repetições e 22 tratamentos (variedades). As variedades Bonança, Esmeralda e Rio Verde apresentaram resistência do tipo antibiose e/ou antixenose, tendo altas taxas de mortalidade, baixas taxas de emergência de adultos e baixo consumo de grãos por S. oryzae. As variedades Pepita e Progresso são suscetíveis com alta emergência de adultos e consumo de grãos por S. oryzae. A presença ou ausência de fissuras no grão é uma importante característica morfológica para determinar a susceptibilidade ou resistência a S. oryzae em variedades de arroz

Do the reward and the promotion policies influence the worker’s motivation?

This paper studies the influence of reward and promotion policy on worker motivation, both intrinsic, understood as belonging to the individual, and extrinsic, seen in the literature as dependent on interventions or external incentives linked to work. In this research, we seek to analyze the level of motivation of the worker under these two concepts, which are the dependent variables. The literature review adresses theories with important discussions about motivation at work, as well as the characteristics used in the rules of a worker's reward and promotion policy, being Transparency, Justice and Controllability, which are the independent variables. A structured questionnaire was used to collect the data. They were examined through factorial analysis and multiple linear regression. The results showed that the justice used in the rules of monetary reward is a characteristic that exerts influence in both the intrinsic and extrinsic motivation. The controllability of the promotion system exerts influence on the extrinsic motivation. However, other variables did not reach statistical significance. This work allowed us to confirm theoretical discussions. Also, it offered a model of analysis with practical and managerial visions of the organizational daily life

Resistance in Rice to \u3ci\u3eTibraca limbativentris\u3c/i\u3e (Hemiptera: Pentatomidae) Influenced by Plant Silicon Content

Tibraca limbativentris Stål (Hemiptera: Pentatomidae) is a major pest causing economic losses to rice cultivation in Brazil. The objectives of this work were to assess different sources of silicon in the induction of plant resistance, to examine the interaction of rice varieties with silicon-based resistance, and to determine the effects of varieties and silicon on stink bug biology. The interaction of rice cultivars BRS Esmeralda, IRGA 429 (widely cultivated in Brazil), and Canela de Ferro (a resistant cultivar), and 2 sources of silicon (K silicate, and Ca + Mg silicate) were studied. Plant parameters measured were percentage of damaged stems, chlorophyll content at 50 and 65 d after emergence, and silicon content. Insect biological parameters measured were the number of live insects, total dry mass, individual insect dry mass, total body surface area, and individual insect body surface area. The interaction between BRS Esmeralda with K silicate and Ca + Mg silicate provided greater plant silicon content and resulted in a lower level of stink bug–damaged stems. These results show that it is possible to increase resistance in rice plants susceptible to T. limbativentris by increasing silicon content. Tibraca limbativentris Stål (Hemiptera: Pentatomidae) es una plaga importante que causa pérdidas económicas al cultivo de arroz en Brasil. El objetivo de este trabajo fue estudiar la interacción de variedades de arroz con diferentes niveles de resistencia y fuentes de silicio en la inducción de la resistencia de las plantas y el efecto sobre la biología de los chinches. Se estudió la interacción de los cultivares de arroz BRS Esmeralda, IRGA 429 (ampliamente cultivado en Brasil), y Canela de Ferro (Resistente), y 2 fuentes de silicio (silicato de K y silicato de Ca + Mg). Los parámetros de la planta medidos fueron: el porcentaje de tallos dañados, el contenido de clorofila a los 50 y 65 días después de la emergencia y el contenido de Si. Los parámetros biológicos de insectos medidos fueron: el número de insectos vivos, la masa seca total, la masa seca de insecto individual, la superficie corporal total y la superficie corporal de insectos individual. La interacción entre BRS Esmeralda con silicato K y silicato de Ca + Mg proporcionó más contenido de silicio vegetal y resultó en un menor porcentaje de tallos dañados por el chinche hedionda. Las variedades de arroz con diferentes niveles de resistencia y el aumento del contenido de silicio en la planta es una opción prometedora en el control de T. limbativentris. Estos resultados muestran que es posible aumentar la resistencia en las plantas de arroz susceptibles a T. limbativentris al aumentar el contenido de silicio

Afecções Osteomusculares na Docência em Dez Escolas Estaduais: Membros Superiores / Musculoskeletal Disorders in Teaching in Ten State Schools: Superior Members

Introdução: as afecções osteomusculares em membros superiores são causadas principalmente por movimentos repetitivos, com posturas errôneas no dia-a-dia, devido ao ambiente de trabalho. Dessa maneira, a frequência com que essas afecções acometem os docentes, podem gerar altos índices de absenteísmo e aposentadorias precoces. Objetivo: Correlacionar sintomatologias osteomusculares causadas por esforço repetitivo em membros superiores dos professores, e as condições ergonômicas na prática do trabalho. Materiais e Métodos: Em 2019, foram avaliados 159 professores de dez escolas estaduais de Mineiros-GO por meio de questionários: De Identificação; Nórdico de queixas musculoesqueléticas e Mapa de Desconforto Postural. As análises estatísticas foram realizadas utilizado o software GraphPad Prism versão 5.02. Resultados: 61% dos professores lecionam dois períodos; 73,6% dos docentes utilizam lousa/giz para lecionar e, destes, 43,7% relataram sentir indisposição ao apagar a lousa. 18% dos professores relataram afastamento das atividades docentes devido a dor e 65% afirmaram usar medicação para dor. Em relação a dor ou incômodo durante o trabalho, 86% sentem dor no ombro. Conclusão: Os professores apresentaram elevada prevalência de sintomas osteomusculares, especialmente nos ombros, o que, por sua vez, pode ocasionar um empecilho no desempenho da atividade profissional

Physical Activity Reduces the Prevalence of Periodontal Disease: Systematic Review and Meta-Analysis

Background: Regular physical activity boosts several physical capacities and reduces many inflammatory markers of several diseases. In this sense, periodontal disease is a multifactorial inflammatory disease of tooth supporting tissues that has been claimed to trigger processes of systemic alterations. The aim of this systematic review and meta-analysis was to assess the effects of physical activity on periodontal disease.Methods: Observational studies published until August 2018 were searched in online databases (PubMed, Scopus, Web of Science, The Cochrane Library, LILACS, OpenGrey, and Google Scholar) after developing a PECO statement that focused on the comparison between adults that followed a routine of exercises or presented a sedentary lifestyle and its effects on periodontal disease. Searching and data extraction were conducted by following PRISMA guidelines. Registration protocol: CRD42016049661. Quality assessment and risk of bias were analyzed by following Fowkes and Fulton protocol.Results: A total of 512 references were retrieved, while only seven were considered eligible. Two meta-analysis involving the prevalence of periodontal disease and unadjusted/adjusted Odds ratio were performed. One of studies did not find association between clinical periodontal parameters and physical activity. Six articles suggested an association between periodontal disease and regular practice of physical activity since a reduction of periodontal prevalence was observed. Moderate level of evidence was demonstrated on GRADE analysis.Conclusion: Physical activity was associated as a potential tool for reduction of periodontal disease prevalence. The frequency of physical activity is directly related to a low occurrence of periodontitis. However, it is important that further investigations evaluate the effects of other exercise variables, such as volume and intensity, on the periodontal disease prevalence

Optical Properties And Antiangiogenic Activity Of A Chalcone Derivate

Chalcones and their derivatives exhibit numerous pharmacological activities such as antibacterial, antifungal, cytotoxic, antinociceptive and anti-inflammatory. Recently, they have been assessed aiming for novel application in nonlinear optics and in the treatment of immune diseases and cancers. In this study, we investigate the optical properties of synthetic chalcona 1E,4E-1-(4-chlorophenyl)-5-(2,6,6-trimethylcyclohexen-1-yl)penta-1,4-dien-3-one (CAB7β) and its antiangiogenic potential using the chorioallantoic membrane (CAM) with the S180 sarcoma cell line. Experimental and theoretical results show intense absorption in the UVA-UVC region, which is associated with a π → π* transition with intramolecular charge transfer from the trimethyl-cyclohexen-1-yl ring to the chlorophenyl ring. Quantum chemical calculations of the first hyperpolarizability, accounting for both solvent and frequency dispersion effects, are in very good concordance with hyper-Rayleigh scattering measurements. In addition, two-photon absorption allowed band centered at 650 nm was observed. Concerning antiangiogenic activity, CAB7β causes a significant reduction in the total number, junctions, length and caliber of blood vessels stimulated by S180 cells reducing the presence of blood vessels, inflammatory cells and others elements related to angiogenic process. It is found that CAB7β is a versatile compound and a promising candidate for linear and nonlinear optical applications, in therapy against sarcoma and phototherapy

A list of land plants of Parque Nacional do Caparaó, Brazil, highlights the presence of sampling gaps within this protected area

Brazilian protected areas are essential for plant conservation in the Atlantic Forest domain, one of the 36 global biodiversity hotspots. A major challenge for improving conservation actions is to know the plant richness, protected by these areas. Online databases offer an accessible way to build plant species lists and to provide relevant information about biodiversity. A list of land plants of “Parque Nacional do Caparaó” (PNC) was previously built using online databases and published on the website "Catálogo de Plantas das Unidades de Conservação do Brasil." Here, we provide and discuss additional information about plant species richness, endemism and conservation in the PNC that could not be included in the List. We documented 1,791 species of land plants as occurring in PNC, of which 63 are cited as threatened (CR, EN or VU) by the Brazilian National Red List, seven as data deficient (DD) and five as priorities for conservation. Fifity-one species were possible new ocurrences for ES and MG states

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio