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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

An investigation of certain molecular interactions of saccharin

Marvel, John Ray, January 1959 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1959. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 71-76).
2

Biochemical and physiological effects of saccharin in the rat

Sims, J. January 1984 (has links)
No description available.
3

The effects of high dietary levels of saccharin on in vivo and in vitro drug metabolism

Heaton, G. D. January 1988 (has links)
No description available.
4

Structural and synthetic studies of a new natural sweetener

Olivier, Johan 13 March 2014 (has links)
M.Sc. (Chemistry) / The name monatin was given to the sweet compound isolated from the roots of the plant Schlerochiton ilicifolius as a mixture of salts, predominantly the sodium salt. The structure of monatin was previously determined by high- field 1 Hand 13 C n . m. r . spectra and confirmed by single crystal X- ray crystallography. The problem of the absolute stereochemistry of monatin did, however, remain unanswered. Several experiments were carried out which provides additional evidence on the relative and absolute stereochemistry of monatin. An approach to the total synthesis of monatin is described. The first phase of this work involves the development of methods for the synthesis of a key intermediate, 1- methyl 2-amino-5- (3'- indolyl)-4-oxopentanoate, using a coupling reaction. The second phase of the synthesis involves the addition of a carboxylic acid equivalent to the ketone group of the coupled product. The final synthetic product was compared with a natural monatin derivative.
5

Spherical Crystallization of Carbamazepine/Saccharin Co-Crystals: Selective Agglomeration and Purification through Surface Interactions

Pagire, Sudhir K., Korde, Sachin A., Whiteside, Benjamin R., Kendrick, John, Paradkar, Anant R January 2013 (has links)
No / Spherical crystallization involves crystallization and simultaneous agglomeration of a crystalline particle using an immiscible phase, which has preferential affinity for the crystal surface. Here, we report application of a spherical crystallization technique to the field of co-crystallization. Carbamazepine/saccharin (CBZ/SAC) co-crystals were generated using reverse antisolvent addition and agglomerated using different bridging liquids. Two crystal forms of CBZ/SAC co-crystals were formed, depending on the levels of supersaturation achieved during processing. The selective agglomeration of co-crystal occurred during the agglomeration stage, depending on the relative interaction between bridging liquid and the crystal surfaces. The computational investigation of isosteric heats of adsorption of the bridging liquids at the prominent crystal surfaces proved to be a useful tool in understanding the surface interactions. The spherical crystallization technique shows opportunity to generate co-crystals and its purification through selective agglomeration.
6

To Eat or Not To Eat: Contributions of Dorsal Hippocampal Neurons and Memory to Meal Onset

Ogawa Henderson, Yoko 11 May 2015 (has links)
There is extensive research regarding the neural mechanisms that control satiety and meal termination; in contrast, there is very limited understanding of how the central nervous system regulates meal onset and thus the duration of the postprandial intermeal interval (ppIMI) and meal frequency. Based on emerging evidence, we hypothesize that dorsal hippocampal neurons, which are critical for episodic memory, form a memory of a meal and inhibit meal onset during the ppIMI. To test whether hippocampal neurons form a memory of a meal, we first determined that ingesting sucrose or isopreferred concentrations of the non-caloric sweetener saccharin increased the expression of the plasticity-related immediate early gene activity-regulated cytoskeleton-associated protein (Arc) in dorsal CA1 hippocampal (dCA1) neurons in Sprague-Dawley rats. Furthermore, repeated exposure to the sucrose meal attenuated the ability of the sucrose to induce Arc expression. Together, these data indicate that orosensory stimulation produced by a sweet taste is sufficient to induce synaptic plasticity in dCA1 neurons in an experience-dependent manner. Second, we showed that reversibly inactivating dorsal hippocampal neurons with infusions of the GABAA agonist muscimol after the end of a sucrose meal accelerated the onset of the next meal, indicating that dorsal hippocampal neurons inhibit meal onset. Lastly, using a clinically-relevant animal model of early life inflammatory injury, we found that neonatal injury (1) impairs hippocampal-dependent memory, (2) decreases the ppIMI and increases sucrose intake, (3) increases body mass, (4) attenuates sucrose-induced Arc expression in dCA1 neurons, and that (5) blocking inflammatory pain with morphine at the time of injury reverses the effects of injury on memory, energy intake and Arc expression. Collectively, the findings of this dissertation support the overarching hypothesis that dorsal hippocampal neurons inhibit meal onset during the ppIMI and suggest that dorsal hippocampal dysfunction may contribute to the development and/or maintenance of diet-induced obesity.
7

Drėgmės trūkumo poveikis žirnių morfofiziologiniams rodikliams / The influence of moisture lack on pear morphofizioligical indices

Klimas, Tautvydas 16 June 2014 (has links)
Magistrantūros studijų baigiamajame darbe pateikiami žirnių fotosintezės pigmentų, prolino, sacharidų bei santykinės drėgmės pokytis lapuose esant drėgmės deficitui. Tyrimų objektas – `Ilgiai` veislės sėjamasis žirnis (Pisum sativum L.). Darbo metodai. Tyrimai atlikti Aleksandro Stulginskio universiteto Agrobiotechnologijos laboratorijoje 2012-2013 metais. Žirniai pasėti į 0,16 m x 0,23 m (aukštis x diametras) vegetacinius indus su substratu (pH − 6,31, P2O5 − 633,94 mg kg-1, K2O – 912 mg kg-1). Eksperimentas vykdytas 6 pakartojimais po 5 augalus inde. Augalai auginti programuojamoje auginimo kameroje esant 20/18 °C (diena/naktis) temperatūrai, 16/8 val. (diena/naktis) fotoperiodui, 50 µmol m-2 s-1 apšviestumui. Augalai auginti programuojamoje auginimo kameroje aukščiau nurodytomis sąlygomis bei esant drėgmės deficitui substrate. Sausros tyrimas pradėtas po sėjos praėjus trims savaitėms. Darbo rezultatai. Esant drėgmės deficitui, patikimai didžiausi chlorofilo a ir b bei karotenoidų kiekiai žirniuose (atitinkamai 2,501 ir 0,821, bei 1,059 mg l-1) nustatyti praėjus 8 dienoms po laistymo. Esmingai didžiausi prolino ir sacharidų kiekiai (atitinkamai 46,543 μM g-1 ir 0,155 g kg-1) žirniuose, esant drėgmės deficitui, nustatytas praėjus 12-ai dienų. Dirvožemio drėgnis (SWC) esmingai kito visą tyrimų laikotarpį. Mažiausias dirvožemio drėgnis (15,12 proc.) nustatytas paskutinę tyrimų dieną, praėjus 16-ai dienų po paskutinio laistymo. Santykinis vandens kiekis lapuose (RWC) esmingai... [toliau žr. visą tekstą] / Master’s thesis submitted to pea’s photosynthesis pigments, proline, saccharins and relative humidity change in leaves and the influence of humidity. The object of researches – ‘Ilgiai’ variety of sowing peas (Pisum sativum L.) Methods. Research carried out at Aleksandras Stulginskis University in Laboratory of Agrobiotechnology 2012–2013. Peas were sown in 0.16 m x 0.23 m (height x diameter) vegetative vessels with the substratum (pH – 6.31, P2O5 – 633.94 mg kg-1, K2O – 912 mg kg-1). The experiment was carried out in 6 replicates of 5 plants in container. Plants were cultivated at programmable climatic chamber at 20/18 °C (day/night) temperature, 16/8 hours (day/night) photoperiod, 50 µmol m-2 s-1 illumination. Plants were grown at programmable climatic chamber by conditions which are set out above and with deficit of moisture in substrate. The investigation of drought launched after three weeks of sowing. Results. In the moisture deficit, reliably the largest chlorophyll a and b and carotenoids amount in peas (respectively 2.501 and 0.821, and 1.059 mg l-1) were determined after 8 days after watering. Essentially the maximum proline and saccharins contents (by 46.543 μM g-1 and 0.155 g kg1) in peas at the moisture deficit were set after 12 days. Soil water content (SWC) was essentially varying through all period of researches. Minimum soil humidity (15.12 percent) was established at the last day of researches, passing 16 days after last watering. Relative water content in... [to full text]
8

Efeito do uso crônico de sacarina comparado ao uso de glicose, frutose ou lipídio, na compensação calórica e no ganho de peso em ratos Wistar

Foletto, Kelly Carraro January 2011 (has links)
Introdução: Há evidências de que o uso de adoçantes não-calóricos (ANC) pode interferir na regulação do apetite, promovendo maior ingestão alimentar, maior ganho de peso (GP) e maior adiposidade. Um estudo prévio, realizado pelo nosso grupo de pesquisa, demonstrou que o uso de sacarina (p=0,005) e aspartame (p=0,048) promoveu maior GP quando comparados ao uso sacarose. Entretanto, devido às limitações metodológicas, não foi possível afirmar se os adoçantes poderiam causar maior GP quando comparados a uma condição inerte; ou ainda, se os sub-componentes da sacarose (glicose e frutose), quando avaliados isoladamente, poderiam contribuir para o menor GP. Além disso, foi verificado que os grupos dos adoçantes compensaram o déficit calórico, ingerindo proporcionalmente mais ração, de modo que, a fração entre a ingestão calórica total e peso corporal não diferiu entre os grupos. Portanto, adicionamos no presente estudo, um terceiro macronutriente com baixo poder de saciedade e potencial indutor de maior GP, o lipídio. Deste modo, o presente estudo contempla analisar o efeito da sacarina comparando-a a condição controle, glicose, frutose e lipídio, além de avaliar o efeito entre cada um dos grupos. Métodos: Foi realizado um experimento controlado envolvendo 40 ratos machos Wistar com peso médio inicial de 300g. Os animais foram randomizados em 5 grupos e receberam água e ração ad libitum, além das seguintes dietas: Controle (20ml de iogurte,75 kcal/semana), Sacarina (0,3%, 75 kcal/semana), Glicose (20%, 139 kcal/semana), Frutose (20%, 139 kcal/semana) ou Lipídio (9%, 139 kcal/semana). As dietas foram administradas 5 dias semanais, por 14 semanas. Realizou-se diariamente o controle da ingestão alimentar e hídrica, e semanalmente o controle do peso corporal. A composição corporal foi determinada pela estimativa da massa gorda, representada pelo peso (g) do tecido adiposo marrom interescapular somado ao tecido adiposo branco (epididimal e retroperitoneal); a massa magra foi representada pela soma do músculo esquelético gastrocnêmio e músculo cardíaco, todos foram removidos imediatamente após o sacrifício dos animais e pesados em balança de precisão milesimal. A análise dos dados foi realizada no SPSS versão 17, utilizou-se Modelo Linear Misto para as medidas longitudinais e ANOVA com teste complementar de Tukey para medidas únicas. Resultados: Houve compensação calórica entre consumo de iogurte e de ração, de modo que a ingestão calórica total (kcal/g) não diferiu entre os grupos (p=0,42). Os grupos também apresentaram similaridade quanto à ingestão hídrica (ml/g) (p=0,27) e composição corporal (p=0,13). Entretanto, o uso de sacarina promoveu maior GP que o controle (p=0,035), sendo similar ao uso de glicose (p=0,06), lipídio (p=0,76) e frutose (p=0,38). Os grupos Lipídio (p=0,016) e Glicose (p<0,001) também ganharam mais peso que o controle, todavia, o grupo Frutose não diferiu deste, mas apresentou GP menor que o grupo Glicose (p=0,006). Conclusão: Independentemente do tipo de suplementação, a regulação do apetite parece ser dependente do aporte calórico, sendo proporcional ao peso corporal, assim como a ingestão hídrica. O uso crônico de sacarina demonstrou promover maior GP, sendo similar ao uso de lipídio, glicose ou frutose. Já, o grupo Frutose apresentou ganho de peso intermediário, diferindo apenas do grupo Glicose. Apesar de haver diferenças quanto ao ganho de peso, a estimativa de massa magra e gorda foi semelhante entre os grupos. Estudos adicionais são necessários para elucidar outros mecanismos, que, independentemente da ingestão calórica estariam envolvidos no maior ganho de peso. / Introduction: There are evidences that the use of nonnutritive sweeteners (NNS) can interfere in the appetite regulation, promoting higher food intake, more weight gain (WG) and the increaseof adiposity. A previous study, performed by our research group, demonstrated that the use of saccharin (p=.005) and aspartame (p=.048) promoted more WG when compared with the use of sucrose. However, due to the methodological limitations, it was not possible to say whether sweeteners could promote more WG compared to an inert condition, or if the sub-components of sucrose (glucose and fructose), when evaluated in isolation, might contribute to less WG. Moreover, it was found that the groups of sweeteners compensated the caloric deficit, ingesting proportionally more chow, so that the ratio between the total caloric intake and body weight did not differ between the groups.Thus, it was added a third macronutrient with low power of satiety and potential inducer of greater WG, as the lipid. Therefore, this study contemplates to analyze the effect of the saccharin, comparing it to the control condition, glucose, fructose and lipid, besides evaluating the effect between each group. Methods: It was conducted a controlled experiment involving 40 male Wistar rats with initial average weight of 300g. The animals were randomized into 5 groups and given water and chow ad libitum, and the following diets: Control (20ml of yogurt, 75 kcal/wk), Saccharin (.3%, 75 kcal/wk), Glucose (20%, 139 kcal/wk), Fructose (20%, 139 kcal/wk) or Lipid (9%, 139 kcal/wk). The diets were administered 5 days weekly for 14 weeks. It was performed daily control of food and water intake, and weekly body weight control. Body composition was determined by estimating fat mass represented by the weight (g) of interscapular brown adipose tissue added to the white adipose tissue (epididymal and retroperitoneal); the lean mass was represented by the sum of the gastrocnemius skeletal muscle and cardiac muscle.Everything was removed immediately after sacrificing the animals and weighed in millesimal precision. The data analysis was performed with SPSS version 17, and it was used Linear Mixed Model for longitudinal measures and ANOVA with Tukey's pot hoc test for single measures. Results: There was caloric compensation between intake of the yogurt and chow, so that the total cumulative caloric intake (kcal/g) did not differ between groups. The groups also had similar regarding the water intake (ml/g) and body composition. However, the use of saccharin promoted greater WG than the control (p=.035), being similar to the use of glucose (p=.06), lipid (p=.76) and fructose (p=.38). Lipid (p=.016) and Glucose groups (p<.001) also gained more weight than the control, though, the Fructose group did not differ from this, but had weight gain less than the Glucose group (p=.006). Conclusion:Whatever type of diet, the appetite regulation appears to be dependent on calorie intake, being proportional to body weight, as well as water intake. The chronic use of saccharin demonstrated to promote greater WG, being similar to the use of lipids, glucose or fructose. Already, the Fructose group showed intermediate weight gain, differing only of Glucose group. Although there are differences in weight gain, the estimate of lean and fat mass was similar between groups. Additional studies are needed to elucidate other mechanisms that, independently of caloric intake, would be involved in more weight gain.
9

Efeito da suplementação isocalórica de sacarina e sacarose no ganho de peso, ingestão calórica, tolerância à glicose e consumo basal de oxigênio em ratos Wistar

Pinto, Denise Entrudo January 2014 (has links)
Introdução: O uso de adoçantes não calóricos (ANC) pode interferir na regulação do apetite, promovendo maior ingestão alimentar, maior ganho de peso (GP) e maior adiposidade. Em estudos anteriores, do nosso grupo, os resultados mostraram que os animais que consumiram iogurte com sacarina e aspartame tiveram um maior ganho de peso comparado ao grupo que usou sacarose. Porém, como o consumo calórico total foi semelhante entre os grupos, o aumento de peso não pôde ser explicado pelo aumento de ingestão calórica. Concluímos, então, que o aumento de peso poderia estar associado à redução do gasto energético induzido pelo adoçante artificial. Estudos anteriores já sugeriram que a sacarina poderia induzir um aumento de peso, porém nenhum estudo até o momento avaliou o consumo de oxigênio basal dos animais. Nesse sentido, é possível que a sacarina possa estar determinando a redução do gasto energético e possivelmente contribuindo para um aumento na glicemia. Desse modo, o presente estudo contempla analisar o efeito da sacarina no consumo basal de oxigênio. Materiais e Métodos: Foi realizado um experimento controlado com 37 ratos Wistar machos adultos pesando entre 180 e 220 g, que foram divididos aleatoriamente em três grupos de acordo com o tipo de exposição tanto para adoçante não calórico (sacarina-SAC), adoçante calórico (sacarose-SUC) ou controle (CONT). Os suplementos foram oferecidos diariamente durante um período de 12 semanas. O ganho de peso, ingestão calórica e controle hídrico foram determinados semanalmente, o consumo basal de oxigênio determinado em repouso (VO2) e RER foram medidos no início do estudo, 5 e 12 semanas, e o teste de tolerância à glicose oral foi determinada nas semanas 6 e 12. Resultados: O uso de sacarina promoveu maior ganho de peso que a sacarose (p=0,031). A ingestão calórica total (kcal/g) diferiu entre os grupos (p=0,029). Os animais que consumiram sacarina ingeriram mais ração. Os grupos apresentaram diferenças quanto à ingestão hídrica, sendo o grupo sacarina com o maior consumo (ml/g) (p=0,018). Entretanto, o consumo de oxigênio e o quociente respiratório não foram significativos. Conclusão: O ganho de peso cumulativo nos animais que consumiram sacarina não pode ser atribuído a uma redução no dispêndio de energia, medida pelo consumo de oxigênio, mas sim pelo aumento da ingestão alimentar e hídrica. / Introduction: The use of non-caloric sweeteners (ANC) can interfere with the regulation of appetite, promoting greater food intake, greater weight gain (WG) and increased adiposity. In previous data, the results showed that the animals that consumed yogurt saccharin and aspartame had a greater increase in weight compared to the group using sucrose. However, as the total calorie intake was similar between the groups, the weight increase could not be explained by the increase in caloric intake. We concluded that weight gain may be associated with decreased energy expenditure induced by artificial sweetener. Previous studies have suggested that saccharin could induce weight gain, but no study to date has evaluated the consumption of oxygen basal animals. In this sense, it is possible that saccharin may be determining reduction in energy expenditure and possibly contributing to an increase in blood glucose. Thus, this study include saccharin analyze the effect on basal oxygen consumption. Materials and Methods: We conducted a controlled experiment with 37 adult male Wistar rats weighing 180-220 g were randomly divided into three groups according to the type of exposure for both non-caloric sweetener (sugar-SAC), calorie sweetener (sucrose-SUC) or control (CONT). The supplements were given daily over a period of 12 weeks. Weight gain, food intake and water control were determined weekly, basal oxygen consumption determined at rest (VO2) and RER were measured at baseline, 5 and 12 weeks and tolerance test oral glucose was determined at week 6 and 12. Results: The use of saccharin promoted greater weight gain than sucrose (p =0.031). The total caloric intake (kcal/g) differ between the groups (p = 0.029), the animals that consumed saccharin ate more food. The groups differed in water intake, and the sugar group with the highest consumption (ml/g) (p = 0.018). However, the oxygen consumption and the respiratory exchange ratio were not significant. Conclusion: The cumulative weight gain in the animals fed saccharin can not be attributed to a reduction in energy expenditure, measured by oxygen consumption, but can be explained by increased food and water intake.
10

Transporte mucociliar e atividade física na vida diária de fumantes saudáveis

Proença, Mahara-Daian Garcia Lemes [UNESP] 26 November 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:50Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-11-26Bitstream added on 2014-06-13T20:09:55Z : No. of bitstreams: 1 proenca_mdgl_me_prud.pdf: 275116 bytes, checksum: 41234546e4bf8949f8d0df066c0a89d6 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação para o Desenvolvimento da UNESP (FUNDUNESP) / A eficiência do transporte mucociliar pode variar em diferentes condições, como na exposição a partículas nocivas da fumaça do cigarro. O presente estudo avaliou os efeitos do cigarro, tanto imediato quanto a curto prazo, no transporte mucociliar nasal de fumantes por meio da quantificação do tempo de trânsito da sacarina (TTS), e os correlacionou com a intensidade de consumo tabagístico. Métodos: Dezenove fumantes ativos (11 homens; 51±16 anos; IMC 23±9 kg/m2; 27±11 cigarros/dia; 44±25 anos/maço), participantes de programa de intervenção antitabagismo, responderam a um questionário referente ao histórico tabagístico e foram submetidos à avaliação da função pulmonar (espirometria) e transporte mucociliar (pelo TTS), este imediatamente e após 8 horas do ato de fumar. Para comparação, um grupo pareado composto por 19 indivíduos saudáveis não-fumantes foi avaliado por meio dos mesmos testes. Resultados: Quando comparados ao TTS de não-fumantes (10±4 min; média±desvio padrão), os fumantes apresentaram tempo de transporte similar imediatamente após fumar (11±6 min; p=0,87) e significativamente mais lento 8 horas após fumar (16±6 min; p=0,005 versus não-fumantes e p=0,003 versus fumantes). Em fumantes... / The mucociliary system is influenced by different conditions such as physical exercise and exposure to cigarette smoke, although the relationship between mucociliary function and the level of physical activity in daily life (PADL) in healthy smokers is unknown. Objectives: To investigate the relationship between mucociliary transport and daily physical activity in smokers. Methods: Fifty two current smokers were submitted to assessment of mucociliary transport (Sacharin Transit Time, STT), carbon monoxide levels in the exhaled air, lung function (spirometry) and smoking history. Furthermore, subjects remained for six days with a waist-worn pedometer in order to determine their level of PADL (steps/day). The tests were also performed in 30 matched healthy nonsmokers who served as control group. Results: Light smokers (≤15 cigarettes/day) had a STT of 9 (6-11) min (median [interquartile range]), which was similar to nonsmokers (8 [5-14]min; p=0.8). Both moderate (16-25 cigarettes/day) and heavy (>25 cigarettes/day) smokers had significantly higher STT (12 [9-17]min and 13 [8-24]min, respectively)... (Complete abstract click electronic access below)

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