Typescript. / Thesis (Ph. D.)--University of Hawaii, 1968. / Bibliography: leaves 144-149. / xiv, 149 l illus., tables

Orientador: Márcia Rossini Justino Mutton / Banca: Eduardo da Silva Martins / Banca: João Martins Pizauro Júnior / Resumo: A utilização de fermentação em estado sólido a partir de subprodutos agroindustriais possibilita a obtenção de várias biomoléculas de interesse industrial. As amilases são enzimas com grande aplicação nas indústrias têxtil, farmacêuticas, alimentícias e sucroalcooleira, representando aproximadamente 25% do mercado mundial. Neste trabalho foram isoladas três linhagens fúngicas (Rhizopus oryzae, Malbranchea pulchella e Chrysosporium zonatum), que apresentaram potencial amilolítico, quando cultivadas em três resíduos agroindustriais (quirera de arroz e de milho e farelo de trigo). Para a cepa que apresentou maior atividade enzimática, avaliou-se melhor substrato, tempo de cultivo, teores de umidade, fontes suplementares de nitrogênio, pH e temperatura de incubação, objetivando otimizar as condições de cultivo. Observou-se que a maior atividade enzimática foi obtida com a cepa de R. oryzae em 24 horas de fermentação, em meio de cultura contendo farelo de trigo como substrato, em temperatura de 35°C, utilizando solução de sais composta de NH4NO3 a 0,1% e MgSO4.7H2O a 0,1% como fonte de nitrogênio. Alterações de pH entre 4,0 e 6,0 não afetaram significativamente a síntese da enzima. A condições ótimas de atuação foram temperatura de 75°C e pH de 4,5. As enzima manteve-se estável a 75°C na ausência de substrato por 25 minutos / Abstract: The use of fermentation in a solid state from agroindustrial byproducts permits the obtaining of several biomolecules of interest the industry, like the enzymes. The amylases are enzymes with great application on the textile, pharmaceutical and food industries, representing around 25% of the worldwide market. In this work three ungal strains (Rhizopus oryzae, Malbranchea pulchella and Chrysosporium zonatum) were isolated. They presented amylolytic potential when cultivated in three agroindustrial by products (brewers rice, corn grits and wheat bran). To the strain that presented the greatest enzyme activity, it was evaluated the best substrate, cultivation time, moisture content, additional sources of nitrogen, pH and incubation temperature, aiming the optimization of cultivation conditions. I was observed that the greatest enzyme's activity was obtained with 24 hours of fermentation, in R. orizae in a culture medium that contained wheat bran as the substrate, at 35°C, using salt solution made with NH4NO3 0.1%, MgSO4.7h2O 0.1% and (NH4)2SO4 0.1% as nitrogen source. pH alterations between 4.0 and 6.0 didn't change significantly the enzyme's activity. The optimum conditions of performance of the enzyme were temperature of 75°C and pH 4.5. The enzyme kept stable in the lack of substrate for 25 minutes in 75°C / Mestre

Both animal and human studies suggest that cognitive bias toward negative information, such as that observed in major depression, may arise through the interaction of cortisol (CORT) and norepinephrine (NE) within the amygdala. To date, there is no published account of the relationship between endogenous NE and CORT levels and cognitive bias. The present study examined salivary CORT and salivary alpha-amylase (sAA), an indirect measure of NE, in relation to masked affective priming of words in young female participants. Women with higher salivary CORT showed increased priming to negative word pairs only when sAA was also high; when sAA was low, no effect of CORT on priming was observed. These results are in line with previous research indicating that increased CORT is linked to enhanced processing of negative information. However, our findings extend this literature in providing evidence that CORT predicts enhanced processing of negatively valenced information only in the presence of higher sAA.

In this study, hydrolytic enzymes from sunn pest (Eurygaster integriceps) and cotton bollworm (Helicoverpa armigera) midguts were identified and characterized in terms of their optimum pH, Km and Vmax values. Hydrolytic activities were also tested for inhibition by several protease and alpha-amylase inhibitors which can be used for the development of insect resistant plants through transgenic technologies. For sunn pest midgut, a low proteolytic activity, belonging mostly to trypsin-like and leucine aminopeptidase-like proteases, and a very high alpha-amylase activity was found in sunn pest midgut, reflecting its high carbohydrate diet. Proteolytic activities could not be inhibited by natural protease inhibitors (SBTI and aprotinin) but inhibited significantly by a general serine protease inhibitor PMSF and metalloprotease inhibitors CdCl2 and CuCl2. alpha-Amylase activity of sunn pest midgut is resistant to inhibition by bean alpha-amylase inhibitor, but inhibited by chickpea, wheat and maize alpha-amylase inhibitors by 26 %, 37 % and 40 %, respectively. For cotton bollworm midgut, a very high proteolytic activity, belonging to serine and metalloprotease type, was detected. alpha-Amylase activity was lower compared to sunn pest midgut, but there were higher and diverse type of proteases, might be reflecting its wide range of host preference. Proteolytic activity was significantly inhibited by both natural protease inhibitors (SBTI and aprotinin). It was also inhibited by several synthetic protease inhibitors (PMSF, E-64, TPCK, CdCl2, CuCl2, Chymostatin). alpha-Amylase activity was inhibited by 60 % by wheat alpha-amylase inhibitor, while maize, chickpea and bean alpha-amylase inhibitors had no effect on cotton bollworm midgut alpha-amylase activity.

Recently, with the development of new technology, researchers have focused on physiological predictors of aggressive behavior, specifically cortisol and alpha amylase. Gordis, Granger, Susman, and Trickett (2006) found the interaction between cortisol and alpha-amylase significantly predicted parent reports of aggression indicating that low levels of physiological reactivity was associated with higher levels of problem behavior. While this research has provided valuable information about aggressive behavior, a major limitation is the majority of research focuses on males, or has not examined gender differences explicitly. This study expanded on work by Gordis et al. (2006) and other researchers on the HPA axis and sympathetic nervous system responses and aggression by using a larger sample, focusing on female adolescents, examining both physical and relational aggression, and utilizing parent and adolescent reports of aggressive behavior. Based on prior literature, I expected that lower levels of salivary cortisol taken at the beginning of the interview and the beginning of the stress task would be associated with higher levels of physical and relational aggression in girls. I also hypothesized that lower levels of cortisol and α-amylase reactivity will be associated with higher levels of physical and relational aggression. Finally, I hypothesized that lower levels of cortisol reactivity coupled with higher levels of α-amylase reactivity will be associated with lower levels of aggressive behavior. Participants in the current study live in moderate- to high-violence areas in Richmond, VA. Participants were 146 adolescent females who were enrolled in a larger longitudinal study on coping with exposure to violence. Most of the adolescents were African-American (91.1%) with a mean age of 13.9 years old (range from 11-17). The changes in physiological responses were monitored during the interview process which included the administration of the Social Competence Interview (SCI). Aggression was measured using the Child Behavior Checklist and Problem Behavior Frequency Scales. In the analyses, I controlled for pubertal status, medication usage, race, and time of day which are all factors that can influence the level of cortisol and alpha-amylase. Results indicated that higher levels of basal cortisol were associated with higher levels of aggressive behavior. In contrast to previous research and prediction, results indicated that symmetry in α-amylase and cortisol predicted lower levels of self-reported physical aggression in girls. Asymmetry in the two systems was associated with higher levels of self-reported physical aggression. These results contribute to the mixed results on female physiological responses and aggression. It also provides support for symmetry in cortisol and α-amylase as a predictor of lower levels of aggressive behavior. Studying a child’s physiological reactions to stress can give insight into behavior regulation, help identify adolescents for prevention/intervention, and serve as markers of treatment progress. These data suggest that physiological associations with aggression may not be the same for males and females, or for youth living in extremely stressful circumstances. Further research is needed to replicate these finding, and specifically to compare these patterns of associations across gender.

In this study sprouting two different wheat cultivars under various environmental conditions revealed that varietal variation is the most important factor affecting α-amylase quantity as well as quality to modify flour functionality significantly, followed by pre-soaking duration and temperature. Sprouted wheat flour post five days germination was utilized at different rates to prepare 100 g composite breads. There was an improvement in baking quality and shelf life of breads containing 1% and 5% sprouted flour resulting in a significantly increased loaf volume, better texture, and less retrogradation during 7 days post baking than the control. This study presents opportunities for industry to fortify baked products with sprouted wheat flour to yield functional whole grain products that are nutrient dense and naturally shelf-stable. / MITACS

In this study, bereavement-related biological and physiological stress reactivity during the discussion of a loss are evaluated by collecting saliva samples in patients aged 55 or more who have lost a spouse within the last 12 months. The concentration of salivary α-Amylase, a marker for stress, is measured. Grief symptoms are also examined in these individuals. BACKGROUND: Grief is a complex psychobiological phenomenon triggered by the loss of a loved one, and that comprises emotions (e.g., yearning, longing, intense feeling of sorrow/emotional pain), thoughts (e.g., thoughts or images about the deceased, difficulty accepting the death, guilt), and behaviors (e.g., avoidance of reminders, spending time with deceased belonging). Because bereavement is a major stressor, it has been suggested that the grief reaction is associated with increased sympathetic activity. Salivary α-Amylase levels have been proposed to be a reliable non invasive biomarker of sympathetic activity. The present study aims to examine salivary α-Amylase reactivity to discussion of the death of a spouse in older adults, and the relationship between this reactivity and grief symptom severity. METHODS: Participants were N=8 individuals who have lost a spouse within the last year (Mean(SD)age=72.8(7.5); 60% women); Mean(SD) time since death=10.6(2.5) months). Participants completed self-reported measures including the 19-item Inventory of Complicated Grief (ICG; total score ranges 0-76; Prigerson et al. 1995). The Mean(SD) ICG score was 30.5(11.5). Saliva samples were collected using cotton swabs and Salivettes at four time points during the screen: right before discussion of the loss (T1), right after discussion of the loss (T2), before screening for psychiatric disorders (T3), and at the end of the screening (T4). Salivary α-Amylase samples were frozen and assayed using a kinetic enzyme assay kit specifically designed and validated for the kinetic measurement of salivary α-Amylase activity. A repeated measure ANOVA, with α-Amylase as the dependent variable, and time as the within subject repeated factor were conducted to examine differences in α-Amylase activity across time points. Further, we examined the association between rise in α-Amylase activity (change between T1 and T2) and ICG scores. RESULTS: The ANOVA revealed a marginally significant main effect of time (F(3,20)=2.74, p=0.07), with α-Amylase activity being more elevated right after discussion of the loss (T2; Mean (SD)=194.9(79.4) µg/dL) compared to the other time points (T1: 140.00(77) µg/dL; T3: 140.5(56) µg/dL; T4: 143.0(70.3) µg/dL). Further, the rise in α-Amylase activity between T1 and T2, was marginally significantly associated with greater grief symptoms (r=0.69, p=0.08). CONCLUSION: Our preliminary findings suggest that discussion of the loss of a spouse may increase salivary α-Amylase activity, reflecting a potential increase in sympathetic activity. Targeting loss-related sympathetic reactivity might be an interesting avenue to decrease grief related distress and impairment. Limitations for this study include a small sample size and the absence of a real control condition. Future research examining sympathetic activity in grief and its relationship with persistent complex bereavement disorder pathophysiology is warranted.

Made available in DSpace on 2014-06-11T19:27:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-07-29Bitstream added on 2014-06-13T20:56:15Z : No. of bitstreams: 1 ferreira_oe_me_jabo.pdf: 412993 bytes, checksum: aae1d57cd30b58d78f8d841727177cc0 (MD5) / A utilização de fermentação em estado sólido a partir de subprodutos agroindustriais possibilita a obtenção de várias biomoléculas de interesse industrial. As amilases são enzimas com grande aplicação nas indústrias têxtil, farmacêuticas, alimentícias e sucroalcooleira, representando aproximadamente 25% do mercado mundial. Neste trabalho foram isoladas três linhagens fúngicas (Rhizopus oryzae, Malbranchea pulchella e Chrysosporium zonatum), que apresentaram potencial amilolítico, quando cultivadas em três resíduos agroindustriais (quirera de arroz e de milho e farelo de trigo). Para a cepa que apresentou maior atividade enzimática, avaliou-se melhor substrato, tempo de cultivo, teores de umidade, fontes suplementares de nitrogênio, pH e temperatura de incubação, objetivando otimizar as condições de cultivo. Observou-se que a maior atividade enzimática foi obtida com a cepa de R. oryzae em 24 horas de fermentação, em meio de cultura contendo farelo de trigo como substrato, em temperatura de 35°C, utilizando solução de sais composta de NH4NO3 a 0,1% e MgSO4.7H2O a 0,1% como fonte de nitrogênio. Alterações de pH entre 4,0 e 6,0 não afetaram significativamente a síntese da enzima. A condições ótimas de atuação foram temperatura de 75°C e pH de 4,5. As enzima manteve-se estável a 75°C na ausência de substrato por 25 minutos / The use of fermentation in a solid state from agroindustrial byproducts permits the obtaining of several biomolecules of interest the industry, like the enzymes. The amylases are enzymes with great application on the textile, pharmaceutical and food industries, representing around 25% of the worldwide market. In this work three ungal strains (Rhizopus oryzae, Malbranchea pulchella and Chrysosporium zonatum) were isolated. They presented amylolytic potential when cultivated in three agroindustrial by products (brewers rice, corn grits and wheat bran). To the strain that presented the greatest enzyme activity, it was evaluated the best substrate, cultivation time, moisture content, additional sources of nitrogen, pH and incubation temperature, aiming the optimization of cultivation conditions. I was observed that the greatest enzyme’s activity was obtained with 24 hours of fermentation, in R. orizae in a culture medium that contained wheat bran as the substrate, at 35°C, using salt solution made with NH4NO3 0.1%, MgSO4.7h2O 0.1% and (NH4)2SO4 0.1% as nitrogen source. pH alterations between 4.0 and 6.0 didn’t change significantly the enzyme’s activity. The optimum conditions of performance of the enzyme were temperature of 75°C and pH 4.5. The enzyme kept stable in the lack of substrate for 25 minutes in 75°C

La restriction des apports alimentaires est une méthode couramment utilisée pour perdre du poids dans les sports à catégories de poids. La réduction des apports caloriques se traduit par une activation des systèmes physiologiques du stress, au niveau central et périphérique, visant à préserver l’homéostasie énergétique. Néanmoins, l’influence sur les paramètres physiologiques, psychologiques et physiques reste controversée et ne permet pas de définir clairement un impact négatif de la restriction alimentaire sur la santé et le niveau de performance. L’objectif de ce travail était d’évaluer l’influence d’une restriction alimentaire sur les indicateurs psychophysiologiques du stress, ainsi que le niveau de performance chez des haltérophiles de haut niveau. Nos résultats ont montré que la restriction alimentaire ne modifiait pas le niveau de performance en haltérophilie, mais induisait une altération des paramètres psychologiques. La période de restriction alimentaire se traduisait par une dissociation de l’activité des systèmes physiologiques du stress, ainsi qu’une modification des réponses hormonales à une compétition simulée d’haltérophilie. Il reste à définir les répercussions à long terme de l’altération des paramètres psychophysiologiques sur la santé et la capacité de performance du sportif. Il serait également intéressant d'étudier l'influence de la restriction alimentaire sur le microbiote intestinal et les répercussions éventuelles sur l'axe intestin-cerveau. / Restricting dietary intake is a widespread method for losing weight in weight categories sports. Reduction of calorie intake results in an activation of the physiological stress systems, both at central and peripheral levels, aiming at preserving energy homeostasis. Nevertheless, the influence on physiological, psychological and physical parameters remains controversial and do not allows to clearly defining a negative impact of dietary restriction on health and performance level. The objective of this study was to evaluate the influence of a dietary restriction period on the psychophysiological indicators of stress, as well as the level of performance in high-level weightlifters. Our results showed that dietary restriction did not modify weightlifting performance level, but resulted in an alteration of the psychological parameters. The dietary restriction period resulted in a dissociation of the activity of the physiological stress systems, as well as a modification of the hormonal responses to a simulated weightlifting competition. It remains to define the long-term impacts of the alteration of psychophysiological parameters on the athlete’s health and performance capacity. It would also be interesting to evaluate the influence of dietary restriction on intestinal microbiota and the possible influence on the gut-brain axis.

Subjects participating in magnetic resonance imaging (MRI) examinations regularly report anxiety and stress related reactions. This may result in impaired data quality and premature termination of scans. Moreover, cognitive functions and neural substrates can be altered by stress. While prior studies investigated pre–post scan differences in stress reactions only, the present study provides an in-depth analysis of mood changes and hormonal fluctuations during the time course of a typical fMRI session. Thirty-nine subjects participated in the study. Subjective mood, salivary alpha-amylase (sAA) and cortisol were assessed at six time points during the lab visit. Associations between hormonal data and neural correlates of a visual detection task were observed using a region of interest approach applied to the thalamic region. Mood and hormonal levels changed significantly during the experiment. Subjects were most nervous immediately after entering the scanner. SAA was significantly elevated after MRI preparation. A subgroup of n = 5 (12.8%) subjects showed pronounced cortisol responses exceeding 2.5 nmol/l. Preliminary fMRI data revealed an association between sAA levels and left thalamic activity during the first half of the experiment that disappeared during the second half. No significant correlation between cortisol and thalamic activity was observed. Results indicate that an fMRI experiment may elicit subjective and neuroendocrine stress reactions that can influence functional activation patterns.