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Dissertations |
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LUANA ANDRADE MENDES SANTANA
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Identification, Characterization of Resistance and Pathogenicity of Enterococcus spp. in donor samples from the Human Milk Bank of the Esau Matos Hospital in Vitória da Conquista (BA).
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Advisor : MARCIO VASCONCELOS OLIVEIRA
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COMMITTEE MEMBERS :
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MARCIO VASCONCELOS OLIVEIRA
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LUCAS MIRANDA MARQUES
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MILENA SOARES DOS SANTOS
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Data: May 27, 2019
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Show Abstract
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Human milk (LH) is the primary food source for newborns (RNs) and infants. Often RNs in the hospital need nutritional support from a Human Milk Bank (BLH). Considering the rich nutrient composition of LH, milked human milk (LHO) can become an excellent culture medium for the development of various microorganisms. At BLH, the donated LHO needs to undergo strict microbiological quality control to be made available. The possible causes of increase of the amount of microorganisms in the human milk can be related to the inadequate techniques of collection, with conditions of hygiene of the donor and the used utensils and with the form of conservation of the food.Among the microorganisms associated with important infections of RNs, which may be contaminants samples of LHO, are the species belonging to the genus Enterococcus that can come from the microbiota of the gastrointestinal tract and skin from healthy donors. These species may be pathogenic for newborns with immunological vulnerability and therefore need to be effectively inactivated by the pasteurization process performed at the BLH. Given the importance of Enterococcus spp. in human pathologies, especially in neonates, the study was identified and characterized the resistance and pathogenicity of these microorganisms in the breast milk of the Hospital of Esau Matos de Vitória da Conquista, associating hygienic-sanitary conditions of the donors with an aim to draw up alternatives that prevent diffusion in a hospital environment. Samples were collected from the nipple-areolar region and donor hands, using single sterile swab, and aliquots and raw milk and pasteurized milk. Isolates of Enterococcus spp. were identified through microbiological cultivation techniques and antibiogram (according to recommendations recommended by CLSI 2017) in a conventional way, together with the use of the chromogenic medium Chromagar Orientation (BD ™ CHROMagar ™ Orientation). Subsequently, molecular biology tests were performed to confirm resistance. Specimens of Enterococcus spp. were identified in 30% of the donors, obtaining a total of 11 isolates. Of these, 63.6% were from swab samples and 36.4% from LHC. Samples of pasteurized human milk did not detect Enterococcus spp. Regarding the antimicrobial susceptibility test, the isolates were sensitive to Ampicillin, Linezolid and Vancomycin. Resistance profile against Penicillin, Norfloxacin and Nitrofurantoin was observed in 18% of the isolates, separately, 9% resistance to Ciprofloxacin and 63% to Tetracycline. The virulence factors were identified in 63% of the isolates for the efaA gene (Antigen A) and 27% presented genotype for the ace gene (Collagen Adesin). The present study presented the responsibility of the microbiological control by the Human Milk Bank and the need to outline alternatives to prevent the arrival of species of Enterococcus spp. in the hospital environment (dispersion of community pathogens in the hospital environment, and the reverse), possibly as causes of important neonatal infections that increase hospitalization time and, consequently, health care costs.
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2
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NIVEA NARA NOVAIS ANDRADE
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IDENTIFICATION, CHARACTERIZATION OF RESISTANCE AND PATHOGENICITY OF Escherichia coli and Klebsiella spp. IN SAMPLES OF DONORS OF THE HUMAN MILK BANK OF THE MUNICIPAL ESAÚ MATOS HOSPITAL IN VITÓRIA DA CONQUISTA (BA).
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Advisor : MARCIO VASCONCELOS OLIVEIRA
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COMMITTEE MEMBERS :
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CLAUDIO LIMA SOUZA
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JESSICA BOMFIM DE ALMEIDA
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LUCAS MIRANDA MARQUES
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MARCIO VASCONCELOS OLIVEIRA
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Data: May 31, 2019
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Show Abstract
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Breast milk (BM) is considered the ideal food for newborns (NBs). Due to its nutritional composition and immunibiological and protective factors, the World Health Organization (WHO) recommends exclusive breastfeeding up to six months.In some situations, such as NB stay in the hospital setting or maternal infectious diseases, it is not possible for NB to obtain BM due to breastfeeding and Human Milk Banks (HMB) emerge as a strategy to guarantee the nutrition of these NBs through the distribuition of milked human milk (MHM) provided by donors registered in the service. The MHM collection can be carried out at the donors' home and the hygienic-sanitary conditions used from milking to processing must follow protocols to avoid microbiological contamination since BM possesses ideal characteristics for the growth of several microorganisms that can be pathogenic to predominantly premature receptors. Among the bacteria that can contaminate the MHM in the milking, transportation and processing stages are Enterobacteria, which are mostly commensal, but have the capacity to acquire pathogenicity and antimicrobial resistance genes. In this family the species of Klebsiella spp and Escherichia coli are important cause of neonatal infections such as meningitis, pneumonia, intestinal infections and sepsis. Therefore, the present study aimed to identify and characterize the pathogenicity and antibiotic resistance profile of E. coli and Klebsiella spp. in samples of donors from the HMB of the Esau Matos Hospital and to correlate the microbial presence with the hygienic-sanitary conditions of the study participants. Samples were collected from the hands and nipple-areolar region, raw human milk aliquot and human milk aliquot after the pasteurization of 30 donors registered at the HMB during the year 2018. The donors also filled out a questionnaire about their socioeconomic and hygienic-sanitary conditions of milking. Samples were seeded using a conventional microbiology technique and strains of Klebsiella were identified in samples from 11 donors (36.6%). Of these, in 36.6% (n = 4) the microorganism was isolated only in cutaneous samples, 36,6% (n = 4) only in raw milked human milk raw (MHMR), 18.2% (n = 2) with positive results in cutaneous and MHMR samples and 9.1% (n = 1) with growth in the three seed samples. E. coli was not isolated in the samples collected. In all strains of Klebsiella spp. the antibiogram with recommendation of the CLSI 2017 was performed. 42.8% (n = 6) of the strains showed resistance to Ampicillin and Sulbactam and 35.7% (n = 5) resistant to Amoxicillin and Clavulanic Acid. The isolates were also subjected to the phenotypic detection of ESBL by disk-approximation, 23.1% (n = 3) presented positive results for this test. The modified Hodge test was performed on all strains to evaluate the presence of the carbapemenase enzyme and all strains tested negative. In addition to the phenotypic tests, the isolates were submitted to the Polymerase Chain Reaction technique to detect the following genes: gyrA, rpoB and pehX, for confirmation of the genus Klebsiella spp. and species of Klebsiella pneumoniae and Klebsiella oxytoca respectively; the genes associated with the production of extended spectrum beta-lactamases (ESBL) SHV, TEM, CTXM-1, CTXM-2 and CTXM-3 and the virulence genes rmpA and wcaG were also investigated. All strains were confirmed as Klebsiella spp., 53.8% (n = 7) identified as Klebsiella pneumoniae, 7.7% (n = 1) identified as Klebsiella oxytoca and 38.5% (n = 5) are not part of the two species surveyed. No ESBL genes and virulence genes were found in the isolated samples.
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3
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SUZETE CARVALHO LANDULFO LUZ
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PHOTODYNAMIC THERAPY: EFFECTIVENESS AND MOLECULAR MECHANISMS OF CURCUMIN ACTION AS FOTOSENSITIZER AGAINST Pseudomonas aeruginosa BIOFILM.
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Advisor : LUCIANO PEREIRA ROSA
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COMMITTEE MEMBERS :
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LUCIANO PEREIRA ROSA
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FRANCINE CRISTINA SILVA ROSA
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NATALIA MAYUMI INADA
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Data: Jun 3, 2019
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Show Abstract
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Pseudomonas aeruginosa is a gram-negative bacteria with a high capacity to form dense biofilms, a complex structure that predisposes the development of antibiotic-resistant phenotypes, contributing to health-care-related infections becoming a serious public health problem worldwide. It is an in vitro research of the experimental type whose objective was to evaluate the effectiveness of different protocols of Photodynamic Therapy (PDT) mediated by curcumin against Pseudomonas aeruginosa biofilms that were submitted to protocols of PDT mediated by curcumin in three different concentrations (5μg / ml, 20μg / ml and 40μg / ml), activated by blue LED light at three different energy doses (3.24J / cm², 5.4J / cm² and 10.8J / cm²) compared to a negative control group ( without treatment) and positive control groups (LED and curcumin, alone, in the concentrations and energy doses delineated for the study), totaling 16 experimental groups. After checking the assumptions of normality and homogeneity, the statistical analysis was performed by Anova and Kruskal-Wallis, with post-test of Bonferroni and Dunn, respectively and the interpretation of the data took into account the values of reduction of Log10 of formative units colony count per ml (CFU / ml) to evaluate the antimicrobial effect of the therapy instituted. The biofilm structure analyzes were performed using confocal laser scanning (CSLM) images and Raman microspectroscopy allowed to evaluate the molecular mechanisms of curcumin action through the observed peaks in the spectrum. The results demonstrated an action centered on the disruptive effect of the biofilm, besides an antimicrobial effect in all PDT protocols, with better results observed in the protocols with higher concentration of photosensitizer and higher energy dose. The curcumin-mediated PDT evaluated in this research proved to be effective not only in reducing the viability of bacterial cells, but mainly because of its antibiofilm effect, and could be used as an antimicrobial potentiator.
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4
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MARISOL PORTO ROCHA
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DEVELOPMENT AND EVALUATION OF THE ANTIMICROBIAL ACTIVITY OF ORAL MICROEMULSIONED RINSE CONTAINING CURCUMIN FOR INTRAORAL PHOTODYNAMIC THERAPY
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Advisor : FRANCINE CRISTINA SILVA ROSA
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COMMITTEE MEMBERS :
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ANDRE LUIS MORAIS RUELA
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FRANCINE CRISTINA SILVA ROSA
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LUCIANO PEREIRA ROSA
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NATALIA MAYUMI INADA
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Data: Jun 17, 2019
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Show Abstract
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PDT (Photodynamic Therapy - PDT) uses a light source, a photosensitizer (FS) and oxygen in the reaction medium to produce as a result highly reactive species capable of causing unfeasibility of microorganisms, such as: bacteria and fungi. The objective of this work was to develop a microemulsion based rinse formulation for dental use in PDT. FScurcumine was incorporated into the formulation and its antimicrobial potential was evaluated using PDT. After the construction of a pseudoternario phase diagram, oil-in-water (O / W) microemulsion composed of polysorbate 80, linseed oil, sobitol, polyethylene glycol 400 and water as an appropriate vehicle for curcumin incorporation. The selected systems were characterized by measurements of conductivity, rheological profile, droplet size and zeta potential. The physical stability of the formulation was also evaluated. The antimicrobial evaluation of the developed mouthwash was evaluated against PDT. A total of 360 acrylic resin specimens were divided into groups (n = 10) with curcumin concentrations of 80 and 40 μg / mL and irradiation times of 10 and 30 minutes. The specimens were contaminated with Staphylococcus aureus methicillin resistant strains, Candida albicans and Escherichia coli in wells of culture medium containing BHI or Sabouraud medium and incubated at 35 ± 2 ° C for 24 hours for the formation of biofilms. After incubation, the experimental groups were treated with PDT, using 460 nm LEDs for activation of FS present in the oral mouthwash. Three other groups were added: control in which no treatment was performed, only the FS and only the FS. The results showed effectiveness above 5Log10 in the groups treated with PDT 40 and 80μg / mL in the time of 30 minutes.
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5
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DANIELBA ALMEIDA DA SILVA
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In vitro and in vivo effects of the nitroxide tempol on inflammation and redox stress induced by acute exposure to cigarette smoke.
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Advisor : RAPHAEL FERREIRA QUEIROZ
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COMMITTEE MEMBERS :
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AMELIA CRISTINA MENDES DE MAGALHAES GUSMAO
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FLÁVIA VIANA SANTA CECÍLIA
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RAPHAEL FERREIRA QUEIROZ
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Data: Jul 5, 2019
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Show Abstract
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Cigarette smoke is a complex mixture of more than 6000 different chemicals substances. In the lung, these components can directly or indirectly trigger inflammation and redox stress, characteristic of some pulmonary diseases, including Chronic Obstructive Pulmonary Disease. Tempol (4-hydroxy-2,2,6,6-tetramethyl piperidine-1-oxyl) and other cyclic nitroxides reduce tissue injury associated with inflammation by mechanisms that are not fully understood. In the literature there is no report on the effects of tempol on lung injury caused by cigarette smoke as well as its involvement in the activation of the Nrf2 pathway. In this context, this study aimed to evaluate the in vitro and in vivo effect of tempol on inflammation and redox stress induced by acute exposure to cigarette smoke. C57BL/6 (n=32) were assigned to four groups (n = 8 each): 1) control exposed to ambient air (CG), 2) mice exposed to cigarette smoke for 5 days (CSG), mice treated 3) preventively or 4) therapeutically with tempol (50 mg/kg/day) and exposed to cigarette smoke for 5 days (TP50+CS and TT50+CS, respectively). The animals were euthanized after 24 h of last exposure to cigarette smoke, and bronchoalveolar lavage and lungs were collected for further analysis. The number of total leukocytes and neutrophils as well as myeloperoxidase concentration and activity increased in the respiratory tract and lung parenchyma of mice exposed to cigarette smoke. As consequence, there was an increase in lipid peroxidation, and nitration and carbonylation of lung proteins. Administration of tempol before or during exposure to cigarette smoke inhibited 60-80% all of the above parameters. Tempol also reduced inflammatory cytokines expression IL-6, IL-1β and IL-17 for basal levels and TNF-α by approximately 50%. On the other hand, IL-10, TGF-β transcription, and activation Nrf2 pathway markers, heme oxygenase 1 (HO-1) and GPx2 increased significantly in the mice treated preventively and therapeutically with the nitroxide, which reflected a higher activity of glutathione peroxidase in the lung homogenate. Then, the effects of tempol were evaluated on intracellular redox state, nitric oxide synthase activity and HO-1 expression in RAW 264.7 murine macrophages. When RAW 264.7 cells were preincubated with tempol (25, 50 and 100 μM) for 24 h and stimulated with cigarette smoke extract, the intracellular oxidation of dichlorofluorescein was reduced in a concentration dependent manner, although nitrite and nitrate concentrations, indirect marker of nitric oxide synthase activity, did not change. In the cells treated with tempol (50 and 100 μM) for 24 h, HO-1 levels increased according to SDS-PAGE / Western Blotting. Collectively, these data indicate that tempol protects cells and tissues against oxidative damage and inflammation on exposure to cigarette smoke probably through the activation of the Nrf2 pathway.
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6
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BRUNO PEREIRA DE ARAÚJO
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Study of the larvicide activity of curcumine by Photodynamic Therapy in different concentrations and blue LED (460nm) about wild Aedes mosquitoes
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Advisor : FRANCINE CRISTINA SILVA ROSA
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COMMITTEE MEMBERS :
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AGDA ALVES DA ROCHA
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FABRICIO FREIRE DE MELO
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FRANCINE CRISTINA SILVA ROSA
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LUCIANO PEREIRA ROSA
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Data: Nov 26, 2019
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Show Abstract
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Introduction: In the first quarter of 2019, there were 273193 confirmed cases of dengue in the country, which represented an increase of 74% over the same period in last year. Also in 2019, in the same period, 15352 probable cases of chikungunya were register, with 2 deaths confirmed (1 in Bahia and 1 in Rio de Janeiro) and 14 deaths are under investigation. As for Zika, in this period, 2344 probable cases were register in the country, with the North and Southeast being the regions with the highest number of probable cases. It is notorious that current policies for vector control of these arboviruses are not effective. Studies of the use of light-activated photosensitizers as an alternative to conventional insecticides for sustainable control of vector mosquitoes such as Aedes (dengue, yellow fever, chikungunya), Anopheles (malaria), Culex (yellow fever) can already be found, showing advantages over conventional insecticides (efficacy, safety, non-mutagenicity and fast degradation). Objective: Evaluate the effectiveness of curcumin-mediated photodynamic therapy (PDT) and blue LED (460nm) on mortality of wild larvae of Aedes aegypti’s mosquitoes. Material and methods: Traps were place in strategic regions identified by the LIRA issued by the Secretariat of Epidemiological Surveillance of the city of Vitória da Conquista-BA. The larvae collected in stages L2 and L3 were feed for 24h with curcumin at concentrations of 10, 20 and 50% mixed with fish food and then underwent blue LED irradiation for 2h (22mW / cm2 and 158.4 J / cm2). The larvae were place in a container with chlorinated water and mortality was followed for 24 and 48h. Control groups in which only larvae were expose to blue LED for 2h and where larvae were only fed with curcumin mixed feed (10, 20 and 50%) were included in the study, in addition to the untreated group. All experiments were repeated after a 2-month interval for confirmation of the results, totaling 256 tests (tests 1 and 2, n = 16) between the PDT 10%, PDT 20%, PDT 50%, curcumin 10%, curcumin 20%, curcumin 50%, blue LED and untreated group. Larvae belonging to the 20% PDT group were submitted to histological slides, confocal microscopy and Raman spectroscopy. Results: All PDT groups showed larvicidal activity, evidenced by the complementary tests performed in the PDT 20% group. Conclusion: The PDT in all concentrations was effective in larval mortality, with the concentration of 20% curcumin showing the best activity with mortality of 100% in 24h.
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7
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MAGDA SOUZA VIANA
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PHOTONIC RESOURCES FOR MICROBIAL INHIBITION AND STIMULATION OF FERMENTATION OF MUST OF PURPLE GRAPE FOR RED WINE FABRICATION: EVALUATION OF THE INITIAL PROCESS
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Advisor : LUCIANO PEREIRA ROSA
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COMMITTEE MEMBERS :
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LUCIANO PEREIRA ROSA
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FRANCINE CRISTINA SILVA ROSA
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BRUNO LOPES BASTOS
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Data: Nov 28, 2019
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Show Abstract
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Wine is considered an alcoholic beverage resulting from the fermentation of grapes. For this, during the process of its production, several chemical reactions are provoked by the yeast, transforming the sugars present in the fruit in alcohol and later giving rise to drink. Obtaining quality wine depends on a number of prerequisites, including environmental factors and human intervention, which, when optimized, result in a significant increase in the quality of the initial process and consequently in the improvement of the final product. In this scenario, the search for improvements in the wine production process has been studied, one of them, analyzed by this work is the application of photostimulation, since light is able to accelerate the yeast metabolism leading to a reduction in the time spent on fermentation. without altering the quality of the drink, as already proven in studies with beer number of prerequisites, including environmental factors and human intervention, which, when optimized, result in a significant increase in the quality of the initial process and consequently in the improvement of the final. product. In this scenario, the search for improvements in the wine production process has been studied, one of which, analyzed by this work is the application of photostimulation, since light is able to accelerate the yeast metabolism leading to a reduction in the time spent on fermentation . without changing the quality of the drink, as proven in studies with beer. Thus, the present work aimed to evaluate the effects of Light Emitting Diodes (LEDs) on microbial selection, fermentation yield and productivity during the initial process of red wine production. The photonic reactors used in the process were made with four RGB (Red - Green - Blue) LED strips (MSS LED Lightining Co., Ltd., Shenzhen, Guangdong, China) measuring 10 cm in length, these strips were fixed to the outer walls. of a 12 x 100 mm glass test tube. Each ribbon contained 6 RGB LEDs, making up a total of 24 RGB LEDs. The reactors were inserted in elermayer containing grape must with yeast of the genus Saccharomyces, isolated from the grapes themselves. For groups that were evaluated for microbiological capacity, the blue LED light was used and for groups that were evaluated the productivity and yield of fermentation, the red light was used. In order to avoid interference from ambient light, in all groups irradiated with light the erlenmeyer containing the must was completely covered with film paper. When performing the intergroup analyzes, it can be observed that the LED was efficient in the bacterial decrease mainly at 48 and 72 hours of application, showing a statistically significant difference (p <0.001) when compared to all times of the Pure group (P24h, P48h and P72h) and at the 24 hour time of the Metabisulfite group (M24h). Another positive point was the alcohol content obtained in the samples that were irradiated with 525nm red LED, which obtained superior results when compared to all other groups (p <0.001) in the final time of 72 hours, showing that the light stimulates the production of ethanol by yeast. Thus, it can be seen that the use of blue (460 nm) and red (630 nm) lights has a positive effect on grape must both in the microbiological decontamination and ethanol production, and can thus be used as an innovative technique as a means of enhance and facilitate the production of red wine.
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8
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ROBERTA DE SOUZA SANTOS
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TAXONIC AND FUNCTIONAL DIVERSITY OF ARBUSCULAR MICRORZIC FUNGI IN COFFEE WITH DIFFERENT TYPE OF MANAGEMENT IN ALTITUDE REGION
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Advisor : PATRICIA LOPES LEAL
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COMMITTEE MEMBERS :
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PATRICIA LOPES LEAL
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JOILSON SILVA FERREIRA
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RENATA CORREIA ASSUNÇÃO SPÓSITO
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Data: Dec 3, 2019
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Show Abstract
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Arbuscular mycorrhizal fungi (AMF) are considered mutualistic organisms that establish symbiotic relationships with most known plant species, offering plenty nutritional benefits. The knowledge regarding the diversity of these fungi is rather low, mainly in agroforestry systems and coffee plantations of Northeast Brazil. Thereby, our aim (1) was to examine the occurrence and diversity of AMF in growing coffee soils under different management (underneath grevília’s canopy and sun-grown with spacing of 1.7 x 0.7 cm and 2.5 x 0.5 cm), and in Soils of surrounding areas under pasture and native forest , located in the municipality of Barra do Choça, Bahia, Brazil and (2) to determine the efficiency of these fungal communities in cowpea (Vigna unguiculata (L.) Walp) culture. Part of soil samples of each area was sent to extraction and identification of AMF spores, whereasthe other was used in the trap culture experiment to determine the caupi-bean efficiency. The trap culture experiment was conductedin a greenhouse, in pots, by using a completely randomized design (CRD), with three repetitions, in which two AMF species in a mixture (Claroideoglomus etunicatum and Rhizophagus clarus) was used as reference treatment, one control treatment not inoculated and five treatments composed by AMF communities from the five areas sampled were analysed. After 80 days of plant growth the experiment was disassembled and the data was tabulated and statistically tested. Spores from 43 AMF morphotypes were recovered and identified from the field samples, distributed among 14 genera belonging to six Glomeromycota families: Glomeraceae (35%), Acaulosporaceae (35%), Gigasporaceae (21%), Ambisporaceae (5%), Archaeosporaceae (2%) e Diversisporaceae (2%). Overall, it was observed the predominance of occurrence of Acaulospora AMFs (34.8%) followed by Glomus (16.27%). According to the frequency of occurrence, Rhizophagus fasciculatus, Acaulospora mellea and Glomus sp.1 were the most dominant species in our study. In the coffee growing areas 12 generas were identified, two of these (Dominikia and Fuscutata) have never been reported in the literature associated to coffee growing in Brazil. Results from the trap culture experiment suggested that the reference treatment, as expected, showed significant results related to both shoot and root dry mass (SDM+RDM) of caupi-bean (7.55 g), and the soil from the shade-grown coffee treatment underneath grevílea was the closest to the reference treatment with values of (SDM+RDM) equal to (4.31 g) and phosphorus content equals to (7.60 g kg-1). Although the treatment of coffee growing underneath native forest did not show any change related to dry mass of caupi-bean, it showed the highest diversity of AMF, 23 morphotypes, suggesting that high diversity of AMF does not translate, necessarily, into benefits to plants. This study advances significantly our knowledge regarding the community composition of AMF in soils of an important coffee growing location in the Brazilian northeast, showing that caupi-bean was responsive to the inoculation of many of these communities.
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9
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LORENA ALVES DE OLIVEIRA SILVA
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Development of nanodisperse systems containing Carbamide peroxide for dental whitening
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Advisor : MATEUS FREIRE LEITE
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COMMITTEE MEMBERS :
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ADRIANO MAIA DOS SANTOS
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ANGELICA FERRAZ GOMES
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MATEUS FREIRE LEITE
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Data: Dec 5, 2019
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Show Abstract
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Growth in the field of aesthetic dentistry has increased, as a result of the requirement in the aesthetic pattern of smile. A healthy and beautiful smile improves self-image and confidence, is directly associated with searching for whiter teeth, which makes dental whitening a requested procedure today. Whitening consists a result of a complex physical and chemical interaction between the tooth and the stain causative agent. When thinking about developing new products, nanotechnology has been pointed out as the technological revolution, which has aroused a huge interest in the scientific community over the past few decades, being one of the main focuses of development and innovation in all countries. Microemulsions (EMs) are nanotechnological, thermodynamically stable, isotropic, dispersed systems consisting of two imiscible liquids. The validation of an analytical method, in the quality control of pharmaceutical products, is to demonstrate that the method is appropriate for a given purpose, that is, the quantitative determination of drugs. In this work, the stability of nanotechnological systems containing carbamide peroxide 16% for tooth whitener was characterized and evaluated, with permeation potential in the dentin canaliles in order to optimize the bleaching process. The selected formulation, from the phase diagram, carbamide peroxide 16% was incorporated, and then characterized (optical microscopy, pH, particle size, polydispersivity index, zeta potential,conductivity). The formulation also submitted to the study of preliminary and accelerated stability. Validated the method for quantifying carbamide peroxide, according to RDC 166 – ANVISA. The product containing Carbamide Peroxide 16% obtained pH values of 5.86 ± 0.05; zeta potential -6.38 ± 0.37mV; droplet size 22.52 ± 0.37nm; Polydispersivity index 0.164±0.02 and Conductivity 0.1063±,001μs/cm. The rheological profile of the analyzed samples presented with thixotropic behavior. The product is stable.
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10
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MAIARA PRATES DE ALMEIDA
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Obtaining tablets containing standard spray-dried hydroalcoholic extract from Lippia alba (Miller) N. E. Brown
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Advisor : MATEUS FREIRE LEITE
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COMMITTEE MEMBERS :
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ANDRE LUIS MORAIS RUELA
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JULIANO GERALDO AMARAL
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MATEUS FREIRE LEITE
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Data: Dec 6, 2019
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Show Abstract
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One of the promising native species to develop a new drug is Lippia alba (Miller) N. E. Brown. This plant is popularly known as “erva-cidreira” and several pharmacological studies were carried out evaluating the activity of both its essential oils and the leaf extracts of its different chemotypes. Among the pharmacological activities of the plant are antiulcerogenic, antispasmodic, anesthetic and sedative, as well as antioxidants and antibacterial. Lippia alba presents as fixed constituents from iridoids, flavonoids and also phenylpropanoids. Acteoside is a glycosylated compound, a phenylpropanoid present in Lippia alba in high quantities than other substances and maybe an analytical marker for the plant. Its pharmacological actions range from antioxidant, anxiolytic and even neuroprotective activity. The present study aims for the development and chemical-physical characterization of tablets obtained from spray-dried Lippia alba hydroalcoholic extract. Molecular modeling analyzes of the structures of 15 compounds identified and quantified for the plant were submitted to the evaluation of anxiolytic and sedative activities with de aid of the PASS program. It was performed spray drying of the hydroalcoholic extract (SDLA) of the plant, the calculation of the Carr index (IC) and Hausner ratio (RH) of the obtained powder. The developing formulations with standardized extracts and the angle of repose analyses for the chosen were investigated. Compression was performed directly and subsequently, the parameters of mean weight, friability, hardness and disintegration of the tablets were analyzed. An analytical method was validated by HPLC to quantify acteoside. The solubility test os the active pharmaceutical ingredient, the extract, was performed from the quantification of the exposed acteoside in aqueous médium with pH variation from 1.0 to 6.8 after 24h. The extract and tablets were dosed and the final product was dissolved. A possible anxiolytic action of acteoside due to inhibition of the enzyme GABA transaminase is suggested by analysis of the results obtained with the PASS server prediction. SDLA 7 extract showed excellent results for IC and RH, being chosen for development. The tablets were approved for the tests of average weight, hardness, friability, and disintegration. The validity method used methanol and formic acid 0,9% (1:9) with the working range from 2.10 to 18.90 µg/mL, analyzed at 325 nm. The linearity, precision, selectivity, robustness, accuracy, and limits of quantification and detection were following current guidelines. The solubility test showed better results in HCl 0.1M. The dosage of the extract and tablets was approved, as well as the dissolution of the developed product.
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