Navegando por Palavras-chave "Synthesis"
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- ItemAcesso aberto (Open Access)Avaliação preliminar da produção de melatonina no tecido adiposo marrom(Universidade Federal de São Paulo (UNIFESP), 2019-12-18) Olescuck, Ingrid Fernandes [UNIFESP]; Amaral, Fernanda Gaspar Do [UNIFESP]; http://lattes.cnpq.br/6398402888086154; http://lattes.cnpq.br/1821363446203117; Universidade Federal de São Paulo (UNIFESP)Objective: Verify the existence of local melatonin production in brown adipose tissue. Methods: We realized three experimental models. In experiment I the animals were euthanized every three hours during 24 hours, with no challenge to the interscapular brown adipose tissue (BAT IE). In experiment II the animals were exposed to hipercaloric food over 24h or to cold temperature (13°C) during 3 hours before euthanasia at ZT10. In experiment III the animals were euthanized at ZT18 and there was no additional challenge to the tissue. In all three experiments the animals were assigned to three groups: control, pinealectomized (PINX) and pinealectomized with oral melatonin replacement (PINX/MEL). We collected BAT IE from all animals for the analyses. Results: mRNA from TPH1 enzyme was accessed by PCR reaction in control, PINX and PINX/MEL groups. However it was not possible to standardize the PCR and the Western Blot reactions for AANAT and HIOMT enzymes. In contrast, immunohistochemistry showed the presence of the proteins from both these enzymes (AANAT and HIOMT) in samples obtained by experiment III. Also, we were able to verify AANAT activity in BAT IE from samples obtained for tests, but we were not able to perform this procedure in our experimental samples due to technical limitations. Discussion: Despite all the technical challenges, the present data strongly suggests the presence of local melatonin production in BAT IE. However, more studies are needed to fully prove that.
- ItemSomente MetadadadosDesenvolvimento de blendas de polímeros estímulo-resposta baseadas em Poli (N-vinilcaprolactama-co-acrilato de N-butila) e poli(3-hexiltiofeno)(Universidade Federal de São Paulo (UNIFESP), 2019-02-20) Nahra, Sara Robert [UNIFESP]; Cristovan, Fernando Henrique [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Conductive polymers discovered in the late 1970s allowed a revolution in the construction of electronic devices, such as rechargeable batteries, photovoltaic cells, among others. Today, these materials have been extensively studied to replace traditional materials in the construction of such devices. In addition, these materials stimulate the adhesion and proliferation of several cell types in biocompatible materials, being able to be used in tissue engineering. However, there are no studies reported for this application. A good material for use as a biomaterial is poly(Nvinylcaprolactam) (PNVCL), which is biocompatible, temperature sensitive and has good mechanical strength, together with poly (3-hexylthiophene), P3HT, which allowed conductive properties to the blend. Due to the characteristics that result in high flexibility, the production of the copolymer with N-vinylcaprolactam (NVCL) and butyl acrylate (Abu) monomer result in high stiffness of NVCL resulting in a more flexible material suitable for health applications. In this project, the syntheses of PNVCL, poly(N-vinylcaprolactam-co-butyl acrylate) [P(NVCL-co-ABu)] and poly(3- hexylthiophene) (P3HT) were performed. The polythiophene (PT) blends were prepared with P(NVCL-co-ABu) by solution, films were obtained by casting and mats were processed by electrospinning. From Fourier Transform Infrared (FT-IR) analysis it was confirmed that blends were formed between P3HT and PNVCL. Through the electrical tests, it showed the samples to be quite resistive. The cytotoxicity tests showed that the conductive polymer increased the cellular viability of the material, even the blends with no electrical conductivity. From the DTG plot, it was found that the presence of P3HT in the copolymer or polymer did not significantly affect the degradation of the material. DSC analysis showed that the presence of P3HT significantly decreased the Tg (from 120 °C to 80 °C) for the polymers with the highest proportion of NVCL in the copolymer and significantly increased the Tg value for the polymers with the highest ABu ratio. It was possible to find the formation of mats for PNVCL, for P3HT/PNVCL and for P3HT/P(NVCL-co-ABu) blends with 25 and 20% ABu using appropriated processing conditions.
- ItemAcesso aberto (Open Access)Estudos visando a preparação e caracterização de derivados da icaridina(Universidade Federal de São Paulo, 2023-10-18) Godoy, Emerson Santos [UNIFESP]; Guadagnin, Rafael Carlos [UNIFESP]; http://lattes.cnpq.br/6202009749007903A Icaridina, também conhecida como Picaridina ou KBR 3023 é um componente químico derivado da pimenta, encontrada nas plantas do gênero Piper L. da grande família Piperaceae. Atualmente, é utilizada comercialmente, na composição de produtos repelentes de insetos, sendo efetiva para mosquitos da família Culicidae, incluindo o Aedes aegypti, um dos principais vetores de doenças graves em países tropicais, assim como o Brasil. Este projeto visa, primeiramente, desenvolver um método prático para isolar a Icaridina pura, a partir de um produto comercial, empregando técnicas de extração líquido-líquido. Após o seu isolamento, pretende-se primeiramente realizar sua análise por técnica de cromatografia em camada delgada, e posteriormente sua caracterização por ressonância magnética nuclear de 1H e 13C, cromatografia gasosa e espectrometria de massas. Por fim, considerando que a estrutura química da Icaridina possui uma hidroxila livre, pretende-se realizar estudos visando a síntese de novos derivados alquilados da Icaridina, utilizando haletos de alquila saturados e métodos convencionais de síntese orgânica. Cabe salientar que, não foram encontrados, até o momento, nas plataformas de busca de literatura científica, derivados alquilados semelhantes aos que pretendemos sintetizar. Ao final, após revisar as análises obtidas, pode-se concluir que a eterificação dos compostos via síntese de éteres de Williamson é uma alternativa viável para obtenção de compostos eterificados, derivados de Icaridina. Esses compostos, posteriormente, em continuidade a este trabalho, poderão ter suas atividades biológicas testadas, em colaboração com outros grupos de pesquisa.
- ItemSomente MetadadadosA joint computational and experimental study of a novel dioxomolybdenum(VI) complex bearing chiral N,N-dimethyllactamide ligand(Elsevier B.V., 2011-09-01) Sensato, Fabricio Ronil [UNIFESP]; Cass, Quezia Bezerra; Lopes, Bianca Rebelo; Lourenco, Tiago Campos; Zukerman-Schpector, Julio; Tiekink, Edward R. T.; Longo, Elson; Andres, Juan; Universidade Federal de São Paulo (UNIFESP); Universidade Federal de São Carlos (UFSCar); Univ Malaya; Univ Estadual Paulista; Univ Jaume 1A new cis-dioxomolybdenum complex MoO2(DMLA)(2) (DMLA = N,N-dimethyllactamide) has been synthesized and characterized by X-ray crystallography, H NMR and IR spectroscopies and electronic structure calculations at DFT/B3LYP level. This compound (chemical formula C10H20MoO6N2) crystallizes in the orthorhombic space group P2(1)2(1)2(1) with Z = 4, a = 6.9357(2) angstrom, b = 11.8761(4) angstrom, c = 17.7251(5), V = 1460.00(8) angstrom(3) and renders a slightly distorted octahedral structure with two long Mo-O bonds (2.253(3) angstrom and 2.257(3) angstrom) trans to each of the Mo=O groups and with two short Mo-O bonds of 1.942(3)4 angstrom cis to them. the Mo=O bond length are 1.715(3) and 1.704(3) angstrom). Each lactamide ligand is bidentate; they are coordinated in their deprotonated form with the carbonyl oxygen occupying a position trans to the Mo=O moiety while the deprotonated hydroxyl oxygen is located cis to them. Structural characterization is complemented by DFT/B3LYP calculations. (C) 2011 Elsevier B.V. All rights reserved.
- ItemAcesso aberto (Open Access)A meta-analysis of plant facilitation in coastal dune systems: responses, regions, and research gaps(Peerj Inc, 2015-02-12) Castanho, Camila de Toledo; Lortie, Christopher J.; Zaitchik, Benjamin; Prado, Paulo Inacio; Universidade de São Paulo (USP); York Univ; Johns Hopkins Univ; Universidade Federal de São Paulo (UNIFESP)Empirical studies in salt marshes, arid, and alpine systems support the hypothesis that facilitation between plants is an important ecological process in severe or 'stressful' environments. Coastal dunes are both abiotically stressful and frequently disturbed systems. Facilitation has been documented, but the evidence to date has not been synthesized. We did a systematic review with meta-analysis to highlight general research gaps in the study of plant interactions in coastal dunes and examine if regional and local factors influence the magnitude of facilitation in these systems. the 32 studies included in the systematic review were done in coastal dunes located in 13 countries around the world but the majority was in the temperate zone (63%). Most of the studies adopt only an observational approach to make inferences about facilitative interactions, whereas only 28% of the studies used both observational and experimental approaches. Among the factors we tested, only geographic region mediates the occurrence of facilitation more broadly in coastal dune systems. the presence of a neighbor positively influenced growth and survival in the tropics, whereas in temperate and subartic regions the effect was neutral for both response variables. We found no evidence that climatic and local factors, such as life-form and life stage of interacting plants, affect the magnitude of facilitation in coastal dunes. Overall, conclusions about plant facilitation in coastal dunes depend on the response variable measured and, more broadly, on the geographic region examined. However, the high variability and the limited number of studies, especially in tropical region, indicate we need to be cautious in the generalization of the conclusions. Anyway, coastal dunes provide an important means to explore topical issues in facilitation research including context dependency, local versus regional drivers of community structure, and the importance of gradients in shaping the outcome of net interactions.
- ItemAcesso aberto (Open Access)Revisão bibliográfica: síntese de derivados de anti-inflamatórios não esteroides (não doadores e doadores de óxido nítrico) e seus mecanismos de ação envolvendo a ciclooxigenase (cox) como agentes antitumorais(Universidade Federal de São Paulo, 2021-12-14) Marcon, Angela Favero [UNIFESP]; Reis, Adriana Karla Cardoso Amorim [UNIFESP]; http://lattes.cnpq.br/8445007688411345; http://lattes.cnpq.br/3967617494306500Os anti-inflamatórios não esteroides (AINEs) são uma classe de anti-inflamatórios de extrema importância no tratamento de sintomas causados por inflamações, sejam elas provocadas por bactérias ou vírus. Eles atuam na inibição da enzima ciclooxigenase (COX), encarregada de produzir prostanoides, principalmente prostaglandinas, substâncias presentes nos tecidos inflamados e que são responsáveis pelos sintomas originados no processo inflamatório. Essa enzima possui duas isoformas conhecidas, sendo uma delas a responsável pela manutenção da integridade da mucosa gastrointestinal (COX-1), enquanto a outra (COX-2) está presente nos tecidos afetados pela inflamação e é responsável pela produção das prostaglandinas presentes neles. Sabendo-se que o câncer é um processo inflamatório e que tecidos afetados por ele expressam a isoforma COX-2, a inibição de COX pode ser de grande ajuda no tratamento dessa patologia. Entretanto, os AINEs não possuem inibição específica, podendo inibir tanto a COX-2 quanto a COX-1, o que dá origem aos efeitos colaterais gastrointestinais ligados ao uso constante de anti-inflamatórios. Nesta revisão bibliográfica, daremos ênfase na busca de artigos, através das plataformas SciFinder e PubMed, que possuam diferentes métodos sintéticos de derivados de AINEs inibidores específicos de COX-2 e não de COX-1, diminuindo seus efeitos colaterais e podendo, assim, serem usados como agentes antitumorais.
- ItemSomente MetadadadosSíntese e caracterização do dímero L-Lactídeo para produção do ácido Poli-L-Láctico visando sua aplicação na área médica(Universidade Federal de São Paulo (UNIFESP), 2021) Cunha, Bruna Leticia De Carvalho [UNIFESP]; Concha, Viktor Oswaldo Cárdenas [UNIFESP]; Universidade Federal de São PauloThe search for polymers from natural sources has increased exponentially, since they have the potential to replace petroleum-derived polymers. Some of these biopolymers are biodegradable, which have wide application as a biomaterial in the health area. Among them, the Poly Lactic Acid (PLA) stands out for being a biodegradable polyester with excellent physical and biological properties. The main route for obtaining high molar mass PLA has the Lactide dimer as a starting monomer, which is commonly produced by depolymerizing PLA. Currently, there is a lack of knowledge about the Lactide obtaining process and divergences for reaction parameters. In addition, the PLA synthesis from this dimer has a high cost production, since the monomer has high added value. In this context, it is crucial to know the L-Lactide process production for use as a monomer for the synthesis of high molar mass PLA, which is widely used in medical applications. Thus, this work aims to evaluate different experimental configurations for the L-Lactide synthesis process, in order to obtain a monomer with high yield and purity and later scale up of the process. For this purpose, three experimental configurations were carried out in which the temperature of 185°C, pressure of 125 mmHg (manometric vacuum), and reaction time of 4 hours were considered. The L-lactide produced had its thermal and spectroscopic properties characterized by the techniques of differential scanning calorimetry (DSC), infrared spectroscopy with Fourier transform (FTIR), and X-ray diffraction (XRD). Experimental results showed the formation of Lactide in some points of the system (connector between reactor and collecting flask, collecting flask and condenser), whose properties were compatible with the standard L-Lactide (PURASORB® L). From the data obtained on a laboratory scale, the conceptual and basic project for the scale up of the process of obtaining L-Lactide was developed.
- ItemSomente MetadadadosStudies on benthic communities of rocky shores on the brazilian coast and climate change monitoring: status of knowledge and challenges(Oxford Univ Press, 2016) Coutinho, Ricardo; Yaginuma, Luciana Erika; Siviero, Fernanda; Santos, Julio Cesar Quintanilha Peres dos; Lopez, Maria Soledad; Christofoletti, Ronaldo Adriano [UNIFESP]; Berchez, Flavio; Ghilardi-Lopes, Natalia Pirani; Ferreira, Carlos Eduardo Leite; Goncalves, Jose Eduardo Arruda; Masi, Bruno Pereira; Correia, Monica Dorigo; Sovierzoski, Hilda Helena; Skinner, Luis Felipe; Zalmon, Ilana RosentalA rocky shores working group (WG) integrated with ReBentos (Monitoring Network for Coastal Benthic Habitats; Rede de Monitoramento de Habitats Bentônicos Costeiros) was created and linked to the Coastal Zones Sub Network of the Climate Network (MCT; Sub-Rede Zonas Costeiras da Rede Clima) and to the National Institute of Science and Technology for Climate Change (INCT-MC; Instituto Nacional de Ciência e Tecnologia para Mudanças Climáticas), to study the vulnerability of benthic communities on rocky shores and the effects of environmental changes on biomes in such environments along the Brazilian coast. The synthesis presented here was one of the products of this GT, and aimed to collect and review existing knowledge on benthic communities present on rocky shores of the Brazilian coast, their associated biodiversity, and the potential of future studies to accurately predict/measure the effects of climate change on such environments and their biota.