Abstract The carbonic anhydrases (CAs) participate in the maintenance of pH homeostasis in various tissues of the human body by catalyzing the reversible reaction CO2 + H2O ⇔ HCO3- + H+. Carbonic anhydrase isoenzyme VI (CA VI) is secreted into the human saliva by the serous acinar cells of the parotid and submandibular glands. The present work was undertaken in order to gain an understanding of the physiological role of CA VI in the oral cavity. CA VI concentrations were compared with other salivary characteristics and with the clinical dental status of the subjects. Saliva samples were collected under strictly controlled conditions from 209 young, healthy men and their CA VI concentrations determined by means of a specific time-resolved immunofluorometric assay. Salivary secretion rate, pH, buffering capacity, α-amylase activity level and counts of lactobacilli and mutans streptococci were also determined. Salivary CA VI concentrations showed positive correlations with salivary secretion rate (r = 0.20, p = 0.003) and amylase activity level (r = 0.46, p < 0.001), but not with pH, buffering capacity, or counts of mutans streptococci or lactobacilli. Salivary CA VI concentration, pH and buffering capacity correlated negatively with the number of decayed, missing or filled teeth (DMFT index). The correlation between salivary CA VI concentration and DMFT index was closest in the subjects with poor oral hygiene. No correlation was found between salivary secretion rate or amylase activity and the DMFT index. The location of CA VI in the enamel pellicle, a thin layer of proteins on dental surfaces providing a protective interface between the tooth surface and the external environment, was demonstrated in samples of extracted teeth using immunostaining with anti-CA VI antibody. Immunostaining for salivary α-amylase, which was used as a positive control, produced virtually the same staining patterns. The presence of CA VI in the natural enamel pellicle was confirmed by Western blotting of pellicle proteins. Histochemical staining of enamel pellicle formed in vitro showed that the bound enzyme retains its CA activity. To determine whether CA VI is transferred into the circulation, blood and saliva samples were collected from four healthy male volunteers at 3-h intervals throughout a 24-h period and assayed for CA VI concentration. CA VI was present in all the serum samples, although its concentration was about 22 times lower than in the saliva. The presence of CA VI in serum was confirmed using a sensitive Western blotting method. Western blotting also showed that serum CA VI is associated with IgG, which may protect the enzyme from proteolytic degradation or target it to sites that do not contain CA VI. The present results suggest that salivary CA VI is not involved in regulation of the actual pH or buffering capacity of the saliva, but it does seem to have a specific role in the oral cavity. High salivary concentrations of CA VI appear to be associated with low caries experience. Since active CA VI is located in the enamel pellicle, it may function locally in the microenvironment of the dental surfaces and accelerate the neutralization of the acid metabolic products of bacterial plaque.

Master of Science / Food Science Institute -- Animal Science & Industry / Karen A. Schmidt / Yogurt starter and probiotic bacteria have been reported to confer health benefits to the consumer; however, to confer these health benefits yogurt and probiotic bacteria should be live and present at the recommended concentration of 6 to 8 log cfu g-1. Cegemett® Fresh (Cognis Nutrition & Health, Monheim, Germany) is a plant extract that possesses antioxidant properties. This research was divided into two experiments. The objective of experiment-I was to investigate the effect of plant extract supplementation on the redox potential (Eh) and the viability of starter cultures (Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus) in nonfat yogurt. Five yogurt samples [non-supplemented, supplemented with 0.5 or 1.0% (w/v) plant extract, or supplemented with 0.014 or 0.028% (w/w) L-cysteine.HCl] were prepared, stored at 5ºC for 50 days and analyzed weekly. L. bulgaricus counts in supplemented yogurts were > 6 log cfu mL-1 for additional 7 to 21 days compared with non-supplemented yogurt; however, S. thermophilus counts in all yogurts were > 6 log cfu mL-1 throughout the storage. Overall, Eh of plant extract supplemented yogurts were similar to non-supplemented yogurt during storage; therefore the improvement in L. bulgaricus viability cannot be attributed to the Eh alone. The objective of experiment-II was to investigate the effect of plant extract supplementation on the buffering ability of the yogurt mix, and on the viability of starter and probiotic (Bifidobacterium animalis ssp. animalis and Lactobacillus acidophilus) cultures in nonfat yogurt stored at 5ºC for 50 days. Nine yogurt samples were prepared with 0.5% (w/v) plant extract, 0.25% (w/v) sodium acetate or no supplement, fermented with starter cultures and B. animalis, L. acidophilus or both probiotics, and analyzed weekly. The plant extract and sodium acetate supplemented yogurt mixes had greater buffering capacities compared with non-supplemented yogurt mix. L. bulgaricus and L. acidophilus counts in supplemented yogurts were > 6 log cfu mL-1 for additional 7 to 35 days compared with non-supplemented yogurts. S. thermophilus and B. animalis counts were not affected by supplementation. These results suggested that greater buffering capacity could improve the viability of L. bulgaricus and L. acidophilus in yogurt during storage.

Com o objetivo de avaliar o efeito da inclusão de níveis crescentes de casca de soja (0, 7, 14, 21 e 28%) no concentrado para equinos, foram realizados dois experimentos, ambos conduzidos no Setor de Equideocultura da Prefeitura do Campus de Pirassununga da Faculdade de Zootecnia e Engenharia de Alimentos. O primeiro experimento consistiu em ensaio de palatabilidade, composto pela análise conjuntas das variáveis: primeira ação (ação realizada pelo animal assim que entrou em contato com os concentrados, cheirou ou comeu), primeira escolha (primeiro concentrado efetivamente ingerido pelo animal), e razão de ingestão (quantidade de cada um dos concentrados ingerida em relação ao total consumido, em um período de 3 minutos). Para tanto, foram utilizados dez equinos, em delineamento inteiramente casualisado. Foi observado efeito (p<0,05) para a primeira ação, sendo que 37,19% dos animais cheiraram e 62,81% dos animais ingeriram os concentrados. Já, para as variáveis primeira escolha e razão de ingestão, não foi observada diferença (p>0,05), demonstrando-se que a preferência e consumo de cada um dos concentrados foram semelhantes. No segundo experimento realizou-se ensaio de digestibilidade aparente dos nutrientes e características físico-químicas das fezes. Cinco éguas dispostas em delineamento quadrado latino 5x5, foram utilizadas. A dieta utilizada apresentou 60% de volumoso (feno de Coast-Cross) e 40% de concentrado, visando atender as exigências nutricionais da categoria animal. Realizaram-se análises para determinação dos teores de matéria seca (MS), matéria mineral (MM), matéria orgânica (MO), extrato etéreo (EE) e proteína bruta (PB), fibra em detergente neutro (FDN), fibra em detergente ácido (FDA), hemicelulose (HC) e energia Bruta (EB), nutrientes para os quais foi determinada a digestibilidade aparente. As características físico químicas das fezes foram analisadas avaliando-se as concentrações de ácidos graxos de cadeia curta (AGCC) o pH, a capacidade tamponante a 5 e a 6, e características de cor e consistência das fezes. Não foi observado efeito (p>0,05) dos níveis de inclusão sobre os coeficientes de digestibilidade dos nutrientes, bem como não houve efeito (p>0,05) sobre as características físico-químicas das fezes. Os Coeficientes de digestibilidade dos nutrientes encontram-se dentro dos valores preconizados pela literatura, sendo os coeficientes médios de digestibilidade aparente de MS, MO, FDN, FDA, HC, PB, EE, EB, respectivamente de: 53,67; 54,71; 47,04; 39,50;54,08; 66,74 e 83,73%. O pH médio observado foi de 6,4 e a capacidade tamponante ao pH 5 (CT5) e capacidade tamponante ao ph 6 (CT6) médias foram respectivamente de 14,09 e 4,41 (mmol/l). Para as características físicas das fezes, cor e consistência, 100% das fezes apresentaram-se esverdeadas e 90% normais, evidenciando que não houve alteração deletéria no intestino grosso dos equinos. A casca de soja pode ser incluída em dietas para equinos, em níveis de até 28% do concentrado, sem causar efeito deletério sobre a digestibilidade dos nutrientes da dieta e sobre a palatabilidade dos concentrados, além de não apresentam efeito deletério sobre as características físico-químicas das fezes, sugerindo manutenção da saúde do trato digestório. / Aiming to evaluate the effect of increasing levels of soybean hulls (0, 7, 14, 21 and 28%) in horses concentrate, two experiments were conducted in the Equideocultura Sector of Faculdade de Zootecnia e Engenharia de Alimentos City Hall. The first experiment was the palatability test, composed by the joint analysis of variables: first action (action performed by the animal as soon as it came in contacted with the concentrates: smelled or ate), first choice (first concentrate effectively ingested by the animal), and ratio intake (amount of each one concentrate ingested in the total consumed, over a period of 3 minutes). Thus, ten horses were used in a completely randomized test. Effect was observed (p<0.05) for the first action, with 37.19% of the animals sniffed and 62.81% of the animals ingested the concentrates. As for the variables: first choice and ratio of intake, there was no difference (p>0.05), demonstrating that the preference and consumption of each one of the concentrates were similar. The second experiment conducted was the nutrient digestibility test and physicochemical characteristics of the feaces. Five mares were used, arranged in 5x5 Latin Square design. The diet had 60% roughage (Coast Cross hay) and 40% concentrate, to meet the nutritional requirements of the animal category. Analysis were made to determine the dry matter (DM), mineral matter (MM), organic matter ( OM), ether extract (EE) and crude protein (CP), neutral detergent fiber (NDF) detergent fiber acid (ADF), hemicellulose (HC) and gross energy (GE), and the apparent digestibility was determined for each nutrient. The physicochemical characteristics of feces were analyzed by evaluating the short chain fatty acids (SCFA) concentrations, pH, buffering capacity (BC) at 5 and 6, and color and faeces consistency. There was no effect (p>0.05) for the inclusion level on the nutrients digestibility, and there was no effect (p>0.05) on the feaces physicochemical characteristics. The digestibility coefficients of nutrients are within the levels recommended by the literature, and the apparent digestibility of DM, OM, NDF, ADF, HC, CP, EE, EB, were: 53.67; 54.71; 47.04, 39.50, 54.08, 66.74 and 83.73%, respectively. The average pH observed was 6.4 and the BC5 and BC6 medium were 14.09 and 4.41 (mmol/l) respectively. For the feaces physical characteristics, color and consistency of the feaces, 100% showed green color and 90% was normal, indicating no deleterious changes in the equine large intestine. Soybean hulls can be included in the horses diet at levels up to 28% of the concentrate, without causing deleterious effect on the nutrients digestibility and the concentrates palatability, and there wasn\'t deleterious effect on the feaces physicochemical characteristics, suggesting maintenance of the digestive tract healthy.

In this thesis, the moisture characteristics of spruce plywood are studied experimentally and numerically with special attention given to moisture storage and release as the indoor humidity changes diurnally. This is referred to as the moisture buffering capacity. Two test facilities (a glass jar facility and a transient moisture transfer facility) are used to measure the moisture accumulation and temperature and relative humidity profiles within spruce plywood. These measured data are used to determine the moisture buffering capacity of spruce plywood and validate a one-dimensional transient numerical model that can be used to calculate the transient heat and moisture transfer in spruce plywood. There is good agreement between the measured and simulated results over the range of test variables investigated. </p><p>This validated numerical model is used to investigate the effect of initial conditions, boundary conditions, thickness and humidity step change on the moisture buffering capacity. In addition, sensitivity studies are performed to investigate the effect of variations in material properties used in the numerical model. The properties that are considered in these sensitivity studies are the sorption isotherm, effective thermal conductivity, heat of sorption and effective diffusion coefficient. These studies show that the sorption isotherm has the greatest effect on the moisture buffering capacity, as well as the temperature and relative humidity profiles within spruce plywood. For example, a ± 10% change in sorption isotherm has a ± 7%, ± 6% and ± 10% effect on the moisture buffering capacity, and the relative temperature and relative humidity change, respectively. </p><p>This thesis also verifies the moisture diffusivity property for spruce plywood, which was developed by Olutimayin and Simonson (2005) to account for moisture storage in cellulose insulation for a single step change in humidity. It was found that for spruce plywood, the moisture penetration depth may be over predicted by an order of magnitude when moisture storage is neglected using a transient analytic solution which does not include moisture storage.

In this thesis, the moisture characteristics of spruce plywood are studied experimentally and numerically with special attention given to moisture storage and release as the indoor humidity changes diurnally. This is referred to as the moisture buffering capacity. Two test facilities (a glass jar facility and a transient moisture transfer facility) are used to measure the moisture accumulation and temperature and relative humidity profiles within spruce plywood. These measured data are used to determine the moisture buffering capacity of spruce plywood and validate a one-dimensional transient numerical model that can be used to calculate the transient heat and moisture transfer in spruce plywood. There is good agreement between the measured and simulated results over the range of test variables investigated. </p><p>This validated numerical model is used to investigate the effect of initial conditions, boundary conditions, thickness and humidity step change on the moisture buffering capacity. In addition, sensitivity studies are performed to investigate the effect of variations in material properties used in the numerical model. The properties that are considered in these sensitivity studies are the sorption isotherm, effective thermal conductivity, heat of sorption and effective diffusion coefficient. These studies show that the sorption isotherm has the greatest effect on the moisture buffering capacity, as well as the temperature and relative humidity profiles within spruce plywood. For example, a ± 10% change in sorption isotherm has a ± 7%, ± 6% and ± 10% effect on the moisture buffering capacity, and the relative temperature and relative humidity change, respectively. </p><p>This thesis also verifies the moisture diffusivity property for spruce plywood, which was developed by Olutimayin and Simonson (2005) to account for moisture storage in cellulose insulation for a single step change in humidity. It was found that for spruce plywood, the moisture penetration depth may be over predicted by an order of magnitude when moisture storage is neglected using a transient analytic solution which does not include moisture storage.

Diss. (sammanfattning) Stockholm : Tekn. högsk. / Härtill 4 uppsatser.

Com o objetivo de avaliar o efeito da inclusão de níveis crescentes de casca de soja (0, 7, 14, 21 e 28%) no concentrado para equinos, foram realizados dois experimentos, ambos conduzidos no Setor de Equideocultura da Prefeitura do Campus de Pirassununga da Faculdade de Zootecnia e Engenharia de Alimentos. O primeiro experimento consistiu em ensaio de palatabilidade, composto pela análise conjuntas das variáveis: primeira ação (ação realizada pelo animal assim que entrou em contato com os concentrados, cheirou ou comeu), primeira escolha (primeiro concentrado efetivamente ingerido pelo animal), e razão de ingestão (quantidade de cada um dos concentrados ingerida em relação ao total consumido, em um período de 3 minutos). Para tanto, foram utilizados dez equinos, em delineamento inteiramente casualisado. Foi observado efeito (p&lt;0,05) para a primeira ação, sendo que 37,19% dos animais cheiraram e 62,81% dos animais ingeriram os concentrados. Já, para as variáveis primeira escolha e razão de ingestão, não foi observada diferença (p&gt;0,05), demonstrando-se que a preferência e consumo de cada um dos concentrados foram semelhantes. No segundo experimento realizou-se ensaio de digestibilidade aparente dos nutrientes e características físico-químicas das fezes. Cinco éguas dispostas em delineamento quadrado latino 5x5, foram utilizadas. A dieta utilizada apresentou 60% de volumoso (feno de Coast-Cross) e 40% de concentrado, visando atender as exigências nutricionais da categoria animal. Realizaram-se análises para determinação dos teores de matéria seca (MS), matéria mineral (MM), matéria orgânica (MO), extrato etéreo (EE) e proteína bruta (PB), fibra em detergente neutro (FDN), fibra em detergente ácido (FDA), hemicelulose (HC) e energia Bruta (EB), nutrientes para os quais foi determinada a digestibilidade aparente. As características físico químicas das fezes foram analisadas avaliando-se as concentrações de ácidos graxos de cadeia curta (AGCC) o pH, a capacidade tamponante a 5 e a 6, e características de cor e consistência das fezes. Não foi observado efeito (p&gt;0,05) dos níveis de inclusão sobre os coeficientes de digestibilidade dos nutrientes, bem como não houve efeito (p&gt;0,05) sobre as características físico-químicas das fezes. Os Coeficientes de digestibilidade dos nutrientes encontram-se dentro dos valores preconizados pela literatura, sendo os coeficientes médios de digestibilidade aparente de MS, MO, FDN, FDA, HC, PB, EE, EB, respectivamente de: 53,67; 54,71; 47,04; 39,50;54,08; 66,74 e 83,73%. O pH médio observado foi de 6,4 e a capacidade tamponante ao pH 5 (CT5) e capacidade tamponante ao ph 6 (CT6) médias foram respectivamente de 14,09 e 4,41 (mmol/l). Para as características físicas das fezes, cor e consistência, 100% das fezes apresentaram-se esverdeadas e 90% normais, evidenciando que não houve alteração deletéria no intestino grosso dos equinos. A casca de soja pode ser incluída em dietas para equinos, em níveis de até 28% do concentrado, sem causar efeito deletério sobre a digestibilidade dos nutrientes da dieta e sobre a palatabilidade dos concentrados, além de não apresentam efeito deletério sobre as características físico-químicas das fezes, sugerindo manutenção da saúde do trato digestório. / Aiming to evaluate the effect of increasing levels of soybean hulls (0, 7, 14, 21 and 28%) in horses concentrate, two experiments were conducted in the Equideocultura Sector of Faculdade de Zootecnia e Engenharia de Alimentos City Hall. The first experiment was the palatability test, composed by the joint analysis of variables: first action (action performed by the animal as soon as it came in contacted with the concentrates: smelled or ate), first choice (first concentrate effectively ingested by the animal), and ratio intake (amount of each one concentrate ingested in the total consumed, over a period of 3 minutes). Thus, ten horses were used in a completely randomized test. Effect was observed (p&lt;0.05) for the first action, with 37.19% of the animals sniffed and 62.81% of the animals ingested the concentrates. As for the variables: first choice and ratio of intake, there was no difference (p&gt;0.05), demonstrating that the preference and consumption of each one of the concentrates were similar. The second experiment conducted was the nutrient digestibility test and physicochemical characteristics of the feaces. Five mares were used, arranged in 5x5 Latin Square design. The diet had 60% roughage (Coast Cross hay) and 40% concentrate, to meet the nutritional requirements of the animal category. Analysis were made to determine the dry matter (DM), mineral matter (MM), organic matter ( OM), ether extract (EE) and crude protein (CP), neutral detergent fiber (NDF) detergent fiber acid (ADF), hemicellulose (HC) and gross energy (GE), and the apparent digestibility was determined for each nutrient. The physicochemical characteristics of feces were analyzed by evaluating the short chain fatty acids (SCFA) concentrations, pH, buffering capacity (BC) at 5 and 6, and color and faeces consistency. There was no effect (p&gt;0.05) for the inclusion level on the nutrients digestibility, and there was no effect (p&gt;0.05) on the feaces physicochemical characteristics. The digestibility coefficients of nutrients are within the levels recommended by the literature, and the apparent digestibility of DM, OM, NDF, ADF, HC, CP, EE, EB, were: 53.67; 54.71; 47.04, 39.50, 54.08, 66.74 and 83.73%, respectively. The average pH observed was 6.4 and the BC5 and BC6 medium were 14.09 and 4.41 (mmol/l) respectively. For the feaces physical characteristics, color and consistency of the feaces, 100% showed green color and 90% was normal, indicating no deleterious changes in the equine large intestine. Soybean hulls can be included in the horses diet at levels up to 28% of the concentrate, without causing deleterious effect on the nutrients digestibility and the concentrates palatability, and there wasn\'t deleterious effect on the feaces physicochemical characteristics, suggesting maintenance of the digestive tract healthy.

No description available.

Articular cartilage has a low propensity for self-repair, due to which 27 million people are affected by osteoarthritis every year in North America. The current repair techniques used for cartilage defects possess flaws that reduce long-term clinical success. Tissue engineering carries with it the promise of engineering hyaline-like cartilage with physical and biochemical properties, similar to that of native cartilage. This being said, the primary objective of my project was to engineer clinically relevant sized articular cartilage constructs. To achieve my objective, first, I investigated the effect of continuous culture on cartilaginous tissue growth. Constructs grown under continuous media flow significantly accumulated more collagen and glycosaminoglycan, and displayed a stratified morphology, similar to that found in native cartilage. The second goal was to further increase chondrocyte proliferation, and extracellular matrix (ECM) accumulation. To achieve this, constructs were grown in a bioreactor with media supplemented with 14 mM sodium bicarbonate (NaHCO3). Constructs cultivated in the bioreactor with NaHCO3 supplementation exhibited a significant (p<0.05) increase in ECM accumulation (a 98-fold increase in glycosaminoglycans and a 25-fold increase in collagen content), cell proliferation (a 13-fold increase), and thickness (a 28-fold increase) compared to all other conditions (static and reactor without NaHCO3 supplementation). The third goal was to engineer cartilage constructs with as little cells as possible, reducing donor site morbidity. From the results obtained, it was evident that the monolayer constructs outperformed all the other constructs (pellet, biopsy, and minced). The final goal was to understand the underlying reason for the increased proliferation. First, I investigated if there were any differences present in intracellular pH (pHi) and intracellular buffering capacity. Second, I determined the role of extracellular pH (pHe) on cell proliferation. In an effort to accurately achieve this, I, for the first time, have reported on measuring pHi of chondrocytes while still in culture (2D and 3D cultures) using a confocal microscope. This study demonstrated the importance of extracellular environments, such as pHe, extracellular buffering capacity, and the presence of carbon dioxide and bicarbonate ions for chondrocyte proliferation. / Thesis (Ph.D, Chemical Engineering) -- Queen's University, 2012-10-30 19:19:32.026

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2008. / Härtill 4 uppsatser.