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Estudo de filmes de poli(ácido lático) obtidos por fiação por sopro em solução reforçados com nanocristais de celulose
(Universidade Federal de São Carlos, 2016-07-15) Parize, Delne Domingos da Silva; Marconcini, José Manoel; https://lattes.cnpq.br/5373845785326215; Mattoso, Luiz Henrique Capparelli; https://lattes.cnpq.br/5839043594908917; https://lattes.cnpq.br/1091897287859389
Solution blow spinning is a technique to produce micro- and nano-scale fibers, forming films with high porosity and surface area. Chemical modifications or the incorporation of nanostructures in these fibers can improve the performance of these films for various applications, such as membranes, tissue engineering and sensors. Therefore, the aim of this work was to study poly(lactic acid) (PLA) films obtained by solution blow spinning reinforced with cellulose nanocrystals (CNC). First, different solvents were evaluated in order to determine the best processing conditions and the feasibility of using the solvent dimethyl carbonate (DMC) in the production of PLA films by solution blow spinning. Polymer concentration showed to be the most significant parameter affecting fiber diameter and DMC presented advantages over 1,1,1,3,3,3-hexafluoro-2-propanol (HFP) and chloroform due its less toxicity, and therefore, is an alternative solvent with an affordable price, using a more environmentally-friendly process. Subsequently, the CNCs were extracted from bleached eucalyptus kraft pulp by sulfuric acid hydrolysis, which were chemically modified with maleic anhydride (CNCMA). Then, composite films of PLA/CNC and PLA/CNCMA were obtained by solution blow spinning and the results indicated that the addition of nanocrystals did not significantly affected fiber diameters, although the fiber diameters tended to decrease with the increase of the nanocrystals concentration. The results also indicated that the nanocrystals may have increased the degree of PLA polymer chains orientation and that the composite films presented a more hydrophilic behavior when compared to the pure PLA film. It suggests that some of the nanocrystals may be on the surface of the fibers, indicating that these composite films are promising for filter and adsorbents membranes application.
Produção de biocombustíveis a partir de glicose e manipueira
(Universidade Federal de São Carlos, 2016-07-15) Chogi, Marianne Akemi Neroni; Silva, Ariovaldo José da; https://lattes.cnpq.br/2240705120810231; Duarte, Iolanda Cristina Silveira; https://lattes.cnpq.br/2626035341263254; https://lattes.cnpq.br/9504282783511179
Biofuels are produced from clean alternative energy sources and one example is biobutanol, a fuel that can be produced by fermentation of different raw materials. The production of butanol is carried out by fermentative metabolism of solvent-producing microorganisms, with acetone and ethanol as major byproducts (ABE fermentation). This work aims to produce biobutanol using strains Clostridium beijerinckii (ATCC 10132) and Clostridium acetobulylicum (ATCC 824) and four different inoculum: ES - swine effluent digester located in the Água Branca Farm in the municipality of Itu; LR - UASB sludge of sewage treatment plant from the city of Porto Feliz; ES - cattle manure; SL - Soil from sugarcane cultivation in Sorocaba region. Glucose and cassava wastewater were used as substrate. The biobutanol production efficiency was evaluated for each strain and inoculum in fermentation batch reactors in which the sole substrate was glucose or cassava wastewater. Both strains produced biofuel, and C. beijerinckii (ATCC 10132) was more efficient yielding 0.33±0.08 g L -1 butanol and 1.65±0.23 g L -1 of ethanol from 30 g L -1 of glucose. When cassava wastewater was used as substrate (10 g L -1 of reducing sugar), the production of butanol was 0.64±0.1 g L -1 and ethanol was 2.47±0.07 g L-1 in comparison to 0.27±0.13 g L -1 butanol and 1.72±0.18 g L -1 of ethanol produced when C. beijerinckii were fed with glucose 10 g L -1 as control. Fermentation inocula produced only butyric acid with concentrations of 0.31±0.04 g L -1 for cattle manure and 0.12±0.013 g L -1 for swine effluent. As the cattle manure showed higher production of butyric acid, this culture was chosen for fermentation with cassava wastewater at COD 5 g L-1 . First of all the inoculum´s DNA was amplified with the pair of primers Sj-F and Sj-R specific for the genus Clostridium. With the confirmation of the clostridia presence, the fermentation with cassava wastewater at 5 g L -1 of COD was performed. This fermentation was compared with the strain C.beijerinckii growing in medium without enrichment and cattle manure with and without medium enrichment. C. beijerinckii biofuel production was 0.02 g L -1 of butanol and 0.69 g L-1 of ethanol after 12 h of fermentation, while cattle manure fermentation yielded 0.168 g L -1 of ethanol after 106 h in enriched medium and 0.026 g L-1 of ethanol in medium without enrichment after 12 h. These results demonstrate the feasibility of using cassava as a substrate for the production of biobutanol, ethanol and the possibility of producing biobutanol by cattle manure and swine effluent since butyric acid is an intermediary product of the pathway leading to butanol synthesis.
Reconhecimento da ligação dos anticorpos anti-HCV com proteínas recombinantes do vírus da hepatite C por meio do teste ELISA
(Universidade Federal de São Carlos, 2016-07-15) Souza, Laís Cristina de; Anibal, Fernanda de Freitas; https://lattes.cnpq.br/4918261968772806; https://lattes.cnpq.br/2916120654952183
Viral hepatitis is a major public health problem worldwide and in Brazil. They are notifiable diseases and according to estimates, billions of people have had contact with the hepatitis and millions are chronic carriers. Infection with hepatitis C virus (VHC) is a major problem worldwide public health due to the high rate of progression to chronicity, the evolutionary potential for cirrhosis and hepatocellular carcinoma, major complications leading to death. In general it can be said that in the last decade there have been major advances in the diagnosis of hepatitis C. In this period there was progressive improvement in sensitivity and specificity of the tests used to detect antibodies against the VHC virus. However, it is necessary that more accurate tests are developed. Thus, considering that the concern for the detection of hepatitis C increases every day, especially in blood banks; the diagnostic methods of this infection are of great clinical relevance and may be used as markers chronicity and indicative of therapeutic efficacy. Therefore, this work proposed to evaluate the connection and recognition of anti-VHC antibody positive and positive genotyped samples in patients with hepatitis C through the standardization of procedures and solutions used in qualitative ELISA. There was the process of awareness of microplates with recombinant chimeric protein, made the analysis of sensitivity, specificity, reproducibility and validity of the method. We obtained from ELISA assays with standardized recombinant proteins a protocol able to have a good performance of the main components of the reaction, and antigens conjugated with good resolution. This study presented ELISA results valid 95.69%, 100% reproducibility, 94.5% sensitivity and specificity 99.3%, higher than the ELISA performed with multiepitopo protein MEHCV who presented with sensitivity (92.86%) and specificity (82.89%). The standard ELISA can be used as a qualitative serological technique aimed at detection of anti-VHC antibodies, as demonstrated with great reactivity in patients infected with VHC.
Participação dos receptores opióides mu e kappa da substância cinzenta periaquedutal na febre induzida por estresse de contenção
(Universidade Federal de São Carlos, 2016-07-15) Silva, Caroline Cristina; Bícego, Kênia Cardoso; https://lattes.cnpq.br/0169967378071426; https://lattes.cnpq.br/6987381269659614
The endogenous opioids are involved in analgesia, thermoregulation and physiological responses to various stressful stimuli such as infection, psychological stress and hypoxia. The mu and kappa receptors in the hypothalamus play a role in endotoxin-induced fever and hypoxia-induced anapyrexia (opposite response to fever), respectively. In addition, periaqueductal gray (PAG), which express both mu and kappa receptors, is involved in defence and thermoregulatory responses. Thus, our hypothesis is that mu and kappa opioid receptors in the PAG modulate the restraint-induced fever in rats by activating and inhibiting this response, respectively. To this end, body temperature (Tb) and heat loss index (HLI; inference for heat conservation/loss) and oxygen consumption (VO ; inference for thermogenesis) of unanesthetized Wistar rats submitted or not to restraint stress, was monitored before and after intra-PAG microinjection of the selective mu opioid receptor antagonist (CTAP; 1 and 10 μg/ 100 nL/ animal), the selective kappa-opioid receptor antagonist (nor-BNI; 1 and 4 μg/ 100 nL/ animal), or vehicle (saline; 100nL/ animal). CTAP and nor-BNI did not change the Tb or the HLI of the animals in euthermia. During the restraint stress, Tb increased in all groups of animals. However, this effect was significantly lower in animals treated with CTAP, and significantly higher in animals treated with nor-BNI. No treatment affected HLI, but CTAP decreased thermogenesis and nor-BNI increased thermogenesis. The results indicate that the mu and kappa opioid receptors in the PAG of rats play a pyrogenic and antipyretic role, respectively, during fever induced by restraint stress and these receptors in PAG may not be essential for the maintenance of Tb during euthermia.