785 resultados para Workplace alcohol and other drugs
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One of the main goals in current evolutionary biology research is to identify genes behind adaptive phenotypic variations. The advances in genomic technologies have made it possible to identify genetic loci behind these variations, also concerning non-model species. This thesis investigates the genetics of the behaviour and other adaptive traits of the nine-spined stickleback (Pungitius pungitius) through the application of different genetic approaches. Fennoscandian nine-spined stickleback populations express large phenotypical differences especially in behaviour, life –history traits and morphology. However the underlying genetic bases for these phenotypical differences have not been studied in detail. The results of the project will lay the foundation for further genetics studies and provide valuable information for our understanding of the genetics of the adaptive divergence of the nine-spined stickleback. A candidate gene approach was used to develop microsatellite markers situating close to candidate genes for behaviour in the nine-spined stickleback. Altogether 13 markers were developed and these markers were used in the subsequent studies with the anonymous random markers and physiologically important gene markers which are already currently available for nine-spined sticklebacks. It was shown that heterozygosity correlated with behaviour in one of the marine nine-spined stickleback populations but with contrasting effects: correlations with behaviour were negative when using physiological gene markers and positive with random markers. No correlation was found between behavioural markers and behaviour. From the physiological gene markers, a strong correlation was found between osmoregulation-related gene markers and behaviour. These results indicate that both local (physiological) and general (random) effects are important in the shaping of behaviour and that heterozygosity– behaviour correlations are population dependent. In this thesis a second linkage map for nine-spined sticklebacks was constructed. Compared to the earlier nine-spined stickleback linkage map, genomic rearrangements were observed between autosomal (LG7) and sex-determing (LG12) linkage groups. This newly constructed map was used in QTL mapping studies in order to locate genomic regions associated with pelvic structures, behaviour and body size/growth. One major QTL was found for pelvic structures and Pitx1 gene was related to these traits as was predicted from three-spined stickleback studies, but this was in contrast to earlier nine-spined stickleback study. The QTL studies also revealed that behaviour and body size/growth were genetically more complex by having more QTL than pelvic traits. However, in many cases, pelvic structure, body size/growth and behaviour were linked to similar map locations indicating possible pleiotropic effects of genes locating in these QTL regions. Many of the gene related markers resided in the QTL area. In the future, studying these possible candidate genes in depth might reveal the underlying mechanism behind the measured traits.
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Kristiina Hormia-Poutasen esitys KOBV-konferenssissa Berliinissä, Saksassa kesäkuussa 2013.
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During the period from 1992 to 1997, interactions of several organisms and Ficus eximia figs, a monoecious species, were studied in plants located in Campinas/SP and Londrina/PR (Brazil). Ficus eximia is pollinated by a single fig wasp species, Pegoscapus sp. (Hymenoptera: Agaonidae, Agaoninae), but also visited by other 14 non-pollinating wasps (Agaonidae, Eurytomidae, Torymidae). Mites (Tarsonemidae), nematodes (Diplogasteridae) and fungi which use the body of the pollinating fig wasp to disperse themselves were also observed.
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Enantiopure intermediates are of high value in drug synthesis. Biocatalysis alone or combined with chemical synthesis provides powerful tools to access enantiopure compounds. In biocatalysis, chemo-, regio- and enantioselectivity of enzymes are combined with their inherent environmentally benign nature. Enzymes can be applied in versatile chemical reactions with non-natural substrates under synthesis conditions. Immobilization of an enzyme is a crucial part of an efficient biocatalytic synthesis method. Successful immobilization enhances the catalytic performance of an enzyme and enables its reuse in successive reactions. This thesis demonstrates the feasibility of biocatalysis in the preparation of enantiopure secondary alcohols and primary amines. Viability and synthetic usability of the studied biocatalytic methods have been addressed throughout this thesis. Candida antarctica lipase B (CAL-B) catalyzed enantioselective O-acylation of racemic secondary alcohols was successfully incorporated with in situ racemization in the dynamic kinetic resolution, affording the (R)-esters in high yields and enantiopurities. Side reactions causing decrease in yield and enantiopurity were suppressed. CAL-B was also utilized in the solvent-free kinetic resolution of racemic primary amines. This method produced the enantiomers as (R)-amides and (S)-amines under ambient conditions. An in-house sol-gel entrapment increased the reusability of CAL-B. Arthrobacter sp. omega-transaminase was entrapped in sol-gel matrices to obtain a reusable catalyst for the preparation enantiopure primary amines in an aqueous medium. The obtained heterogeneous omega-transaminase catalyst enabled the enantiomeric enrichment of the racemic amines to their (S)-enantiomers. The synthetic usability of the sol-gel catalyst was demonstrated in five successive preparative kinetic resolutions.
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This thesis focuses on flavonoids, a subgroup of phenolic compounds produced by plants, and how they affect the herbivorous larvae of lepidopterans and sawflies. The first part of the literature review examines different techniques to analyze the chemical structures of flavonoids and their concentrations in biological samples. These techniques include, for example, ultraviolet-visible spectroscopy, mass spectrometry, and nuclear magnetic resonance spectroscopy. The second part of the literature review studies how phenolic compounds function in the metabolism of larvae. The harmful oxidation reactions of phenolic compounds in insect guts are also emphasized. In addition to the negative effects, many insect species have evolved the use of phenolic compounds for their own benefit. In the experimental part of the thesis, high concentrations of complex flavonoid oligoglycosides were found in the hemolymph (the circulatory fluid of insects) of birch and pine sawflies. The larvae produced these compounds from simple flavonoid precursors present in the birch leaves and pine needles. Flavonoid glycosides were also found in the cocoon walls of sawflies, which suggested that flavonoids were used in the construction of cocoons. The second part of the experimental work studied the modifications of phenolic compounds in conditions that mimicked the alkaline guts of lepidopteran larvae. It was found that the 24 plant species studied and their individual phenolic compounds had variable capacities to function as oxidative defenses in alkaline conditions. The excrements of lepidopteran and sawfly species were studied to see how different types of phenolics were processed by the larvae. These results suggested that phenolic compounds were oxidized, hydrolyzed, or modified in other ways during their passage through the digestive tract of the larvae.
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Mother-pup interaction, as well as other behavioral reactions were studied during the lactation period in 24 litters of Wistar rats and their dams fed either a 16% (control - C; 12 litters) or a 6% (malnourished - M; 12 litters) protein diet. The diets were isocaloric. Throughout lactation there was a 36.4% weight loss of M dams and a 63% body weight deficit in the M pups when compared to control pups. During this period, half of the litters were exposed daily to additional tactile stimulation (CS or MS), while the other half were submitted to normal rearing conditions (CN or MN). The tactile stimulation of pups (handling) consisted of holding the animal in one hand and gently touching the dorsal part of the animal's body with the fingers for 3 min. A special camera and a time-lapse video were used to record litter behavior in their home cages. Starting at 6 p.m. and ending at 6 a.m., on days 3, 6, 12, 15, 18 and 21 of lactation, photos were taken at 4-s intervals. An increase in the frequency (154.88 ± 16.19) and duration (455.86 ± 18.05 min) of suckling was observed throughout the lactation period in all groups compared to birth day (frequency 24.88 ± 2.37 and duration 376.76 ± 21.01 min), but the frequency was higher in the C (84.96 ± 8.52) than in the M group (43.13 ± 4.37); however, the M group (470.2 ± 11.87 min) spent more time suckling as compared with the C group (393.67 ± 13.09 min). The M dams showed a decreased frequency of resting position throughout the lactation period (6.5 ± 2.48) compared to birth day (25.42 ± 7.74). Pups from the C group were more frequently observed separated (73.02 ± 4.38) and interacting (258.99 ± 20.61) more with their mothers than the M pups (separated 66.94 ± 5.5 and interacting 165.72 ± 12.05). Tactile stimulation did not interact with diet condition, showing that the kind of stimulation used in the present study did not lead to recovery from the changes induced by protein malnutrition. The changes in mother-pup interaction produced by protein malnutrition of both may represent retardation in neuromotor development and a higher dependence of the pups on their mothers. These changes may represent an important means of energy saving and heat maintenance in malnourished pups.
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Kartta kuuluu A. E. Nordenskiöldin kokoelmaan
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The objective of the present study was to investigate the influence of the establishment of dominance relationships and social stress on plasma cortisol and metabolite levels in Nile tilapia (Oreochromis niloticus). During the 30-day experiment, the fish weighing 236 ± 29 g were kept in individual aquaria, except for two pairings lasting 6 h each. Blood samples were taken from the animals before and after pairing. Display, approach, attack, rebuff, chase flight, and coloration were carried out on days 16 and 30. Activities and behaviors characteristic of the establishment of dominance relationships were described. It was possible to classify all experimental fish (N = 30) as dominant or subordinate. No differences were detected between dominant (N = 15) and subordinate (N = 15) fish during isolation or after pairing in cortisol (isolated: 5.76 ± 0.98 vs 5.42 ± 0.63; paired: 10.94 ± 1.62 vs 11.21 ± 2.45 µg/dl), glucose (isolated: 60.02 ± 4.9 vs 67.85 ± 16.16; paired: 110.44 ± 15.72 vs 136.26 ± 22.46 mg/dl), triglyceride (isolated: 167.87 ± 5.06 vs 185.68 ± 7.24; paired: 210.85 ± 13.40 vs 221.82 ± 12.70 mg/dl) or total protein levels (isolated: 7.01 ± 0.42 vs 6.69 ± 0.59; paired: 9.21 ± 0.62 vs 9.51 ± 0.66 g/dl). However, when isolated (N = 30) and paired (N = 30) tilapia were compared, there were significant differences in cortisol and metabolite levels. The similar response presented by dominant and subordinate tilapia indicates that establishment of dominance relationships was a stressor for both groups.
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Hemodynamic care during postoperative management of myocardial revascularization should include vasorelaxing drugs to insure adequate graft and coronary flow, and stimulation of stroke volume to maintain vascular perfusion pressure. We tested the cardiac (inotropic and lusitropic) and vascular (relaxant) effects of diltiazem (0.1 nM to 0.1 mM), dobutamine (10 µM to 10 mM) and amrinone (10 µM to 1 mM) on isolated rat atria and thoracic aorta, and also on isolated human saphenous vein (HSV) and human mammary artery (HMA). Dobutamine produced a maximal positive inotropic effect (+dF/dt max = 29 ± 7%) at its ED50 for aortic relaxation (88 ± 7 µM). Conversely, at their ED50 for aortic relaxation diltiazem depressed myocardial contractility and amrinone did not exhibit myocardial effects. In HSV and HMA contracted with 80 mM potassium, diltiazem and dobutamine (but not amrinone) had a vasorelaxant activity similar to that in rat aorta. Norepinephrine-contracted human vessels were significantly more sensitive than potassium-contracted vessels to the relaxant effect of amrinone (ED50 HMA = 15 ± 5 µM, ED50 HSV = 72 ± 31 µM, P < 0.05). We conclude that at concentrations still devoid of myocardial effects dobutamine and amrinone are effective dilators in graft segment vessels and rat aorta contracted by membrane depolarization. If the difference between aortic and myocardial tissue still holds in human tissues, at the appropriate concentrations these drugs should be expected to improve cardiac performance while still contributing to the maintenance of graft patency.
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Atherosclerosis is a chronic inflammatory disease which may cause obstructions of the coronary, cerebral and peripheral arteries. It is typically multifactorial, most often dependent on risk factors such as hypercholesterolemia, diabetes, smoking, hypertension, sedentarism, and obesity. It is the single main cause of death in most developed countries due to myocardial infarction, angina, sudden death, and heart failure. Several epidemiological studies suggest that moderate alcohol intake, especially red wine, decrease cardiac mortality due to atherosclerosis. The alcohol effect is described by a J curve, suggesting that moderate drinkers may benefit while abstainers and heavy drinkers are at higher risk. Experimental studies indicate that most beneficial effects of drinking are attributable to flavonoids that are present in red wine, purple grape juice and several fruits and vegetables. The mechanisms include antiplatelet actions, increases in high-density lipoprotein, antioxidation, reduced endothelin-1 production, and increased endothelial nitric oxide synthase expression which causes augmented nitric oxide production by endothelial cells. These findings lead to the concept that moderate red wine drinking, in the absence of contraindications, may be beneficial to patients who are at risk of atherosclerotic cardiovascular events. Moreover, a diet based on fruits and vegetables containing flavonoids may be even more beneficial.
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Keratinases are enzymes of great importance involved in pathogenic processes of some fungi. They also have a widespread ecological role since they are responsible for the degradation and recycling of keratin. On the one hand, studying them furthers our knowledge of pathogenicity mechanisms, which has important implications for human health, and on the other hand, understanding their ecological role in keratin recycling has biotechnological potential. Here, a wild-type keratinolytic Candida parapsilosis strain isolated from a poultry farm was treated with ethyl methanesulfonate in order to generate mutants with increased keratinase activity. Mutants were then cultured on media with keratin extracted from chicken feathers as the sole source of nitrogen and carbon. Approximately 500 mutants were screened and compared with the described keratinolytic wild type. Three strains, H36, I7 and J5, showed enhanced keratinase activity. The wild-type strain produced 80 U/mL of keratinolytic activity, strain H36 produced 110 U/mL, strain I7, 130 U/mL, and strain J5, 140 U/mL. A 70% increase in enzyme activity was recorded for strain J5. Enzymatic activity was evaluated by zymograms with proteic substrates. A peptidase migrating at 100 kDa was detected with keratin, bovine serum albumin and casein. In addition, a peptidase with a molecular mass of 50 kDa was observed with casein in the wild-type strain and in mutants H36 and J5. Gelatinase activity was detected at 60 kDa. A single band of 35 kDa was found in wild-type C. parapsilosis and in mutants with hemoglobin substrate.
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Our objective was to compare the pattern of organ dysfunctions and outcomes of critically ill patients with systemic lupus erythematosus (SLE) with patients with other systemic rheumatic diseases (SRD). We studied 116 critically ill SRD patients, 59 SLE and 57 other-SRD patients. The SLE group was younger and included more women. Respiratory failure (61%) and shock (39%) were the most common causes of ICU admission for other-SRD and SLE groups, respectively. ICU length-of-stay was similar for the two groups. The 60-day survival adjusted for the groups’ baseline imbalances was not different (P = 0.792). Total SOFA scores were equal for the two groups at admission and during ICU stay, although respiratory function was worse in the other-SRD group at admission and renal and hematological functions were worse in the SLE group at admission. The incidence of severe respiratory dysfunction (respiratory SOFA >2) at admission was higher in the other-SRD group, whereas severe hematological dysfunction (hematological SOFA >2) during ICU stay was higher in the SLE group. SLE patients were younger and displayed a decreased incidence of respiratory failure compared to patients with other-SRDs. However, the incidences of renal and hematological failure and the presence of shock at admission were higher in the SLE group. The 60-day survival rates were similar.
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Commercial cashew apple juice is widely accepted in the Brazilian market. Cashew apple has high content of ascorbic acid, an important nutrient to human beings. Ascorbic acid content in food can be affected by processing and storage conditions. Commercial cashew apple juice samples, ready-to-drink and concentrated, were analyzed. The ascorbic acid content, total titratable acidity, total soluble solids, and pH of the juices were determined during storage at 4 °C after the containers were opened. The ascorbic acid content presented a great variability among the samples analyzed ranging from 37.3 to 46.3 mg.100 mL-1 in ready-to-drink juices and from 75.7 to 152 mg.100 mL-1 in concentrated juices. The storage of commercial cashew apple juices for 48 hours at 4 °C resulted in ascorbic acid losses of up to 8.8% for concentrated and 6.4% for ready-to-drink juices. The other parameters remained stable during storage. The results of this study point to the importance of considering ascorbic acid losses in commercial cashew apple juices which occurs after opening but before the expiration date expires.
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Four varieties of an Andean indigenous crop, quinoa (Chenopodium quinoa Willd.), were evaluated as a source of dietary fiber, phenolic compounds and antioxidant activity. The crops were processed by extrusion-cooking and the final products were analyzed to determine the dietary fiber, total polyphenols, radical scavenging activity, and in vitro digestibility of starch and protein. There were no significant differences in the contents of total dietary fiber between varieties of quinoa. In all cases, the contents of total and insoluble dietary fiber decreased during the extrusion process. At the same time, the content of soluble dietary fiber increased. The content of total phenolic compounds and the radical scavenging activity increased during the extrusion process in the case of all 4 varieties. There were significant differences between the varieties and the content of total polyphenols. The in vitro protein digestibility of quinoa varieties was between 76.3 and 80.5% and the in vitro starch digestibility was between 65.1 and 68.7%. Our study demonstrates that quinoa can be considered a good source of dietary fiber, polyphenols and other antioxidant compounds and that extrusion improves the nutritional value.