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- ItemBusca de biomarcadores em longevidade humana : investigação dos genes MTHFD1L e SERPINA3(Universidade Federal do Espírito Santo, 2019-02-25) Ayres, Rayanne Ferreira; Paula, Flávia de; Errera, Flávia Imbroisi Valle; Sena, Geralda Gillian Silva; Naslavsky, Michel Satya; Maranduba, Carlos Magno da CostaHuman longevity, which exceeds the average life expectancy of the population, is a multifactorial characteristic determined by environmental factors and genetic predisposition. Although several studies investigate the influence of environmental components on longevity, the role of genetic variants in this trait is still unclear. Genes that participate in the metabolism of amino acids and genes that act in inflammatory processes, such as the genes MTHFD1L and SERPINA3, respectively, could influence the variations of the life span of individuals of a population. Thus, this study aimed to evaluate whether there is an association between the polymorphisms of MTHFD1L (rs11754661) and SERPINA3 (rs4934) with human longevity in individuals attended at a referral hospital in Geriatrics in Grande Vitória-ES, Brazil. A total of 436 participants were selected, divided into long-lived groups (over 85 years old) and elderly people close to the life expectancy of the population (between 70 and 75 years). Genotyping was performed by real-time PCR and the identified polymorphisms were in HardyWeinberg equilibrium. Statistical analyzes were performed using Odds Ratio (OR) tests with Confidence Interval of 95%, χ² and Fisher, with p-value ≤0.05. No association of the rs4934 polymorphism of the SERPINA3 gene with longevity was observed. However, the G allele of polymorphism rs11754661 of the MTHFD1L gene behaved as a risk allele for human longevity in the analyzed population (p = 0.027, OR = 1.976, 95% CI ranging from 1.080 to 3.616), as well as the GG genotype P = 0.030, OR = 2.006, 95% CI ranging from 1.070-3.761), whereas the AG genotype served as a protection factor (p = 0.041, OR = 0.518, 95% CI ranging from 0.275 to 0.974). The results suggest that the polymorphism rs11754661 of the MTHFD1L gene is associated with human longevity in the sample of individuals from Grande Vitória-ES, Brazil and that the rs4934 polymorphism of the SERPINA3 gene is not associated with longevity in the sample evaluated.
- ItemReduction of the enzyme loading for hydrolysis of alkaline pretreated green coconut husk(Universidade Federal do Espírito Santo, 2019-05-23) Bolivar Telleria, Maria; Fernandes, Antônio Alberto Ribeiro; Fernandes, Patrícia Machado Bueno; Santos, Alexandre Martins Costa; Tussell, Raúl TapiaCoconut (Coco nucifera) is a crop largely produced by tropical countries for its water and meat. This represents a handling and environmental issue as an estimated of 46 million tons of waste in the form of coconut husks is produced each year. Different alternatives to obtain added-value products from this waste have been studied, including the production of ethanol. One of the most expensive steps on the ethanol production process with this kind of substrates is the enzymatic hydrolysis due to the high cost of the enzymes used. Unfortunately, green coconut husk has a high lignin content, which inhibits the enzymes and leads to the use of high enzyme loading increasing the production cost. The detoxification of the hydrolysates prior to enzymatic hydrolysis and the addition of polymers, proteins and surfactants have proven to decrease the inhibition of the enzymes improving the enzymatic hydrolysis. This enzymatic hydrolysis enhancement enables the reduction of enzyme loading, leading to a process with higher economic viability. The purpose of this study is to reduce the enzyme loading used for the hydrolysis of alkaline pretreated green coconut husk by using different additives. First, the detoxification of the alkaline pretreated green coconut husk slurry with activated charcoal was evaluated. The direct and indirect (inside a pouch) addition of the activated charcoal showed a decrease in acetic acid concentration but also in fermentable sugars concentration. No benefit was seen at the end of the process while adding activated charcoal. In addition, the use of activated charcoal heavily inhibited the fermentation. Successively, the direct addition of casein or PEG to the alkaline pretreated green coconut husk slurry to enhance the enzymatic hydrolysis without a detoxification step was tested. The addition of casein showed an improvement on the hydrolysis but not on the results for the overall process. On the other hand, the addition of PEG helped improve the enzymatic hydrolysis and results from the overall process under some of the conditions tested. Initially, the enzymatic hydrolysis with the addition of different concentrations of PEG4000 (0.010, 0.025 or 0.050 g/g bm) using three enzyme loadings (3.0, 5.0 or 7.5 FPU/g bm) was performed. The use of 0.050 g PEG4000/g bm enabled to obtain the best results using a low enzyme loading of 5.0 FPU/g bm. Subsequently, the addition of PEGs with various chain lengths was examined, using 0.050 g PEG/g bm and 5.0 FPU/g bm. PEG4000 presented better results than PEG8000 and the PEG mixture (15,000 and 20,000 g/mol). Furthermore, the hydrolysates containing PEG4000 were fermented to monitor ethanol production. No inhibition was observed for the hydrolysates of alkaline pretreated green coconut husk treated with PEG4000. The addition of PEG4000 proved to be a viable procedure to decrease the enzyme loading used during enzymatic hydrolysis of alkaline pretreated green coconut husk to produce ethanol by 66.7%.
- ItemEstudo da mutação c.1080+1G>T do gene P3H1 em pacientes com osteogênese imperfeita atendidos no Estado do Espírito Santo, Brasil(Universidade Federal do Espírito Santo, 2019-02-26) Santos, Mário Sérgio Ribeiro dos; Zeidler, Sandra Ventorim von; Paula, Flavia de; Nogueira, Breno Valentim; Batitucci, Maria do Carmo Pimentel; Errera, Flavia Imbroisi ValleOsteogenesis imperfecta (OI) is a rare inherited bone disease characterized by fragile and brittle bones that results in fractures in children and adults. It is a disorder related to collagen, the main component of the extracellular matrix of connective tissues. In recent years, many genes have been identified with different inheritance patterns related to OI. These anomalies are commonly related to the mutations in genes encoding type I collagen, responsible for the appearance of the dominant autosomal forms of the disease. Among those inherited in an autosomal recessive form stands out the P3H1 gene, the encoder of one of the three protein components forming the 3- hydroxylation complex of proline of collagen type I. This work aimed to study the c.1080+1G>T mutation of the gene P3H1 in patients with clinical diagnosis of OI in the state of Espírito Santo (ES), Brazil. Sanger Sequencing was performed in 10 patients attended at reference hospitals in the treatment of OI in the ES state. The c.1080+1G>T mutation of the gene P3H1 was not identified in any patient studied in this study. Despite the small sample size of this research, the results of this work suggest that this mutation is rare in patients with ES. Characterizing the distribution of mutations in genes related to OI increases our knowledge about the genetic and phenotypic variability present in the disease in different populations and helps in the planning of new strategies for molecular diagnoses of OI.
- ItemAlta pressão hidrostática como ferramenta de seleção direcionada em S. cerevisiae para produção de etanol 2g pela casca de coco verde(Universidade Federal do Espírito Santo, 2019-03-11) Santos, Luiza Favarato; Fernandes, Patricia Machado Bueno; Santos, Alexandre Martins Costa; Torres, Fernando Araripe GonçalvesThe green coconut shell is a pollutant residue of the environment generated to tons in Brazil and that brings several environmental problems in its disposal. Therefore, using it for the production of renewable energy is an important sustainable solution for the mitigation of the environmental impact and for the generation of energy. Yeast Saccharomyces cerevisiae represents one of the microorganisms most used in the fermentation industries for the production of biofuels from lignocellulolytic residues. There are already on the market strains of this yeast capable of degrading lignocellulolytic residues, which have been developed to increase the yield of the process, making it feasible financially on an industrial scale. The high pressure hydrostatic (HHP) is a tool that simulates three types of different stresses in the yeast: the ethyl, the thermal and the oxidative, which are very common in fermentation dornas. In addition, studies have shown that fermentation occurs more rapidly when the yeast is under HHP. Therefore, HHP can be used as a targeted selection tool to obtain a strain with higher fermentation capacity and greater resistance to fermentation stresses, increasing the yield of the process. The aim of this work was to apply a selective pressure to the S. cerevisiae strain G2-104 using high hydrostatic pressure in order to obtain a strain with a higher fermentation capacity in green coconut shell culture medium, to increase the yield of the second generation ethanol production process.
- ItemExpressão da proteína Bcl-2 como potencial biomarcador de progressão tumoral em carcinoma epidermóide oral(Universidade Federal do Espírito Santo, 2019-03-08) Có, Anna Clara Gregorio; Zeidler, Sandra Ventorin von; Nogueira, Breno Valentim; Pereira, Fausto Edmundo Lima; Silva, Tarcília Aparecida daOral squamous cell carcinoma (OSCC) is the most common histological type of cancer of the oral cavity and presents a high mortality rate, about 50% of individuals diagnosed with OSCC evolve to death within a period of up to 5 years. Currently, there are no biomarkers able to predict prognosis and tumor progression features, in this way, the study of proteins responsible for apoptotic control and therefore involved in carcinogenesis has been in evidence. Thus, this study aims to evaluate the expression of Bcl-2 protein (B-cell lymphoma protein 2) as a prognostic biomarker and tumor progression in OSCC. We used clinical and follow-up data from 109 individuals with a conclusive diagnosis of OSCC. Histopathological analysis of gradation, patter of invasion, tumor lymphocytic infiltrate, perineural, vascular and lymphatic tumor invasion were evaluated on stained slides in Hematoxylin and Eosin. Fragments of tumor tissue, dysplasia and adjacent epithelium to the tumor were arranged in tissue microarrays and submitted to immunohistochemistry using anti-Bcl-2 antibody, clone 124. High Bcl-2 expression was observed in the tumor tissue, in relation to the adjacent epithelium to the tumor and dysplasia (p = 0.033), as well as on the tumor invasion front associated with the high degree of tumor lymphocytic infiltrate (p = 0.001). No difference was observed in Bcl-2 expression in tumor tissue when compared to clinical-pathological variables: tumor size, lymph node involvement, staging, age, gender, alcohol consumption and smoking. Additionally, Bcl-2 expression was not associated with prognosis in global and disease-free survival analyzes. We conclude that Bcl-2 protein may play an important role in indicating the malignant transformation potential of the oral epithelium in the tumor progression model used and may be a potential biomarker for the evolution of high-grade dysplasia for the CEO. However, in this study, Bcl-2 expression did not prove to be a good prognostic biomarker.