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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.
21

Ultrasound assisted processing of solid state pharmaceuticals : the application of ultrasonic energy in novel solid state pharmaceutical applications, including solvent free co-crystallisation (SFCC) and enhanced compressibility

Alwati, Abdolati A. M. January 2017 (has links)
The objective of this study was to develop a new method for co-crystal preparation which adhered to green chemistry principles, and provided advantages over conventional methods. A novel, solvent-free, high-power ultrasound (US) technique, for preparing co-crystals from binary systems, was chosen as the technology which could fulfil these aims. The application of this technology for solid state co-crystal preparation was explored for ibuprofen-nicotinamide (IBU-NIC), carbamazepine-nicotinamide (CBZ-NIC) and carbamazepine-saccharin (CBZ-SAC) co-crystals. The effect of different additives and processing parameters such as power level, temperature and sonication time on co-crystallisation was investigated. Characterisation was carried out using DSC, PXRD, FTIR, Raman and HPLC. In addition, an NIR prediction model was developed and combined with multivariate analysis (PLS) and chemometric pre-treatments. It was found to be a robust, reliable and rapid method for the determination of co-crystal purity for the IBU-NIC and CBZ-NIC pairs. Co-crystal quantification of US samples helped to optimise the US method. Finally, a model formulation of paracetamol containing 5% and 10% PEG 8000 was ultrasonicated at maximum power with different exposure times. A comparison of technological and physicochemical properties of the resulting tablets with those of the tablets obtained using the pressing method evidenced significant differences. This suggested that US energy dissipation (mechanical and thermal effects) was the main mechanism which caused the PAR form I tabletability to improve. It was found that the ultrasound–compacted tablets released the drug at a slower rate compared to pure PAR. This technique was shown to be useful for improving tabletability for low-compressible drugs without the need to use a conventional tabletting machine.
22

Efeitos agudos da pressão positiva contínua de vias aéreas (CPAP) e impacto da umidificação e vazamento aéreo sobre o transporte mucociliar e inflamação nasal de indivíduos sadios / Acute effects of continuous positive airway pressure on mucociliary clearance of healthy subjects: the impact of humidification and air leak

Oliveira, Luciana Rabello de 23 April 2007 (has links)
A pressão positiva contínua nas vias aéreas (CPAP) é o tratamento de escolha para pacientes com Apnéia Obstrutiva do Sono, mas muitos sintomas nasais conseqüentes da terapia são relatados. Vazamentos aéreos pela boca e alterações do epitélio respiratório são importantes no desenvolvimento de sintomas nasais e a umidificação aquecida é utilizada no alívio destes sintomas. O objetivo deste trabalho foi o de investigar os efeito agudos do nCPAP e o impacto da umidificação aquecida e vazamento aéreo no transporte mucociliar e inflamação nasal de indivíduos sadios. Para este fim avaliamos o transporte mucociliar nasal in vivo (através do Teste da Sacarina), a transportabilidade in vitro do muco nasal (através do Método Palato de Rã), lavado nasal e sintomas respiratórios (através de uma Escala Visual Analógica) de dezesseis indivíduos sadios antes e após aplicação aguda do CPAP sobre diferentes condições: CPAP com e sem umidificação aquecida e CPAP com e sem vazamento aéreo. O transporte mucociiar nasal in vivo aumentou significativamente após todas as intervenções com CPAP. Não houve diferença significativa da transportabilidade do muco, contagem total e diferencial de células inflamatórias provenientes do lavado nasal após nenhuma das intervenções com o CPAP. Houve um aumento significante da percepção subjetiva dos sintomas respiratórios estudados após o uso do CPAP sem umidificação e com vazamento aéreo. Concluimos que o uso agudo do CPAP independente da umidificação ou vazamento aéreo, aumenta significativamente o transporte mucociliar nasal in vivo, não altera significativamente a transportabilidade do muco nasal nem a composição celular de amostras de lavado nasal. Já o uso do CPAP sem umidificação e com vazamento aéreo causa aumento significativo dos sintomas de ressecamento nasal e de garganta, coriza e obstrução nasal. / Continuous positive airway pressure (CPAP) is the treatment of choice for patients with Obstructive Sleep Apnea but yet nasal symptoms are often reported. Air leaks and changes of the respiratory epithelium are important in the development of nasal symptoms and heated humidification is used to alleviate these symptoms. The aim of this study was to investigate the acute effects of CPAP and the impact of heated humidification and air leak on the nasal mucociliary clearance and nasal inflammation of healthy volunteers. To this end we evaluated nasal mucociliary clearance in vivo (through the Saccharin Test), in vitro nasal mucus transportability (through the Frog Palate Model), nasal lavage and respiratory symptoms (through a Visual Analogue Scale) of sixteen healthy volunteers before and after acute CPAP application under different conditions: CPAP with and without heated humidification and with and without air leak. In vivo nasal mucociliary clearance increased significantly after all CPAP interventions. There was no significant difference in mucus transportability, total or differential inflammatory cell count from the nasal lavage after any CPAP intervention. There was a significant increase in the subjective perception of the respiratory symptoms studied after the use of CPAP without humidification and with air leak. We conclude that the acute use of CPAP independently of humidification or air leak significantly increases in vivo nasal mucociliary clearance, doesn\'t change mucus transportability and total or differential cell count. However, the use o CPAP without humidification and with air leak significantly increased nasal and throat dryness, coryza and nasal obstruction subjective perception.
23

Efeitos agudos da pressão positiva contínua de vias aéreas (CPAP) e impacto da umidificação e vazamento aéreo sobre o transporte mucociliar e inflamação nasal de indivíduos sadios / Acute effects of continuous positive airway pressure on mucociliary clearance of healthy subjects: the impact of humidification and air leak

Luciana Rabello de Oliveira 23 April 2007 (has links)
A pressão positiva contínua nas vias aéreas (CPAP) é o tratamento de escolha para pacientes com Apnéia Obstrutiva do Sono, mas muitos sintomas nasais conseqüentes da terapia são relatados. Vazamentos aéreos pela boca e alterações do epitélio respiratório são importantes no desenvolvimento de sintomas nasais e a umidificação aquecida é utilizada no alívio destes sintomas. O objetivo deste trabalho foi o de investigar os efeito agudos do nCPAP e o impacto da umidificação aquecida e vazamento aéreo no transporte mucociliar e inflamação nasal de indivíduos sadios. Para este fim avaliamos o transporte mucociliar nasal in vivo (através do Teste da Sacarina), a transportabilidade in vitro do muco nasal (através do Método Palato de Rã), lavado nasal e sintomas respiratórios (através de uma Escala Visual Analógica) de dezesseis indivíduos sadios antes e após aplicação aguda do CPAP sobre diferentes condições: CPAP com e sem umidificação aquecida e CPAP com e sem vazamento aéreo. O transporte mucociiar nasal in vivo aumentou significativamente após todas as intervenções com CPAP. Não houve diferença significativa da transportabilidade do muco, contagem total e diferencial de células inflamatórias provenientes do lavado nasal após nenhuma das intervenções com o CPAP. Houve um aumento significante da percepção subjetiva dos sintomas respiratórios estudados após o uso do CPAP sem umidificação e com vazamento aéreo. Concluimos que o uso agudo do CPAP independente da umidificação ou vazamento aéreo, aumenta significativamente o transporte mucociliar nasal in vivo, não altera significativamente a transportabilidade do muco nasal nem a composição celular de amostras de lavado nasal. Já o uso do CPAP sem umidificação e com vazamento aéreo causa aumento significativo dos sintomas de ressecamento nasal e de garganta, coriza e obstrução nasal. / Continuous positive airway pressure (CPAP) is the treatment of choice for patients with Obstructive Sleep Apnea but yet nasal symptoms are often reported. Air leaks and changes of the respiratory epithelium are important in the development of nasal symptoms and heated humidification is used to alleviate these symptoms. The aim of this study was to investigate the acute effects of CPAP and the impact of heated humidification and air leak on the nasal mucociliary clearance and nasal inflammation of healthy volunteers. To this end we evaluated nasal mucociliary clearance in vivo (through the Saccharin Test), in vitro nasal mucus transportability (through the Frog Palate Model), nasal lavage and respiratory symptoms (through a Visual Analogue Scale) of sixteen healthy volunteers before and after acute CPAP application under different conditions: CPAP with and without heated humidification and with and without air leak. In vivo nasal mucociliary clearance increased significantly after all CPAP interventions. There was no significant difference in mucus transportability, total or differential inflammatory cell count from the nasal lavage after any CPAP intervention. There was a significant increase in the subjective perception of the respiratory symptoms studied after the use of CPAP without humidification and with air leak. We conclude that the acute use of CPAP independently of humidification or air leak significantly increases in vivo nasal mucociliary clearance, doesn\'t change mucus transportability and total or differential cell count. However, the use o CPAP without humidification and with air leak significantly increased nasal and throat dryness, coryza and nasal obstruction subjective perception.
24

Stanovení sladidel a konzervantů v energetických nápojích metodou HPLC / Determination of sweeteners and preservatives in energy drinks by HPLC

Zídková, Anežka January 2019 (has links)
This master´s thesis is focused on simultaneous determination of sweeteners and preservatives in energy drinks by liquid chromatography coupled with DAD and ELSD detection. The method was optimized for determination of aspartame, acesulfame K, saccharin, sucralose, steviol glycosides, benzoic acid and sorbic acid. Analyses were carried out on the Poroshell 120 EC-C18 column (4.6 x 150 mm, 2.7 m, Agilent) using mixture of methanol, acetone and water with formic acid and trimethylamine as a gradient mobile phase at a flow rate 0,5 mL•min-1. Validation parameters were determined (limit of detection, limit of quantification, repeatability and recovery). The validated method was applied on real samples.
25

Ultrasound Assisted Processing of Solid State Pharmaceuticals. The application of ultrasonic energy in novel solid state pharmaceutical applications, including solvent free co-crystallisation (SFCC) and enhanced compressibility

Alwati, Abdolati A.M. January 2017 (has links)
The objective of this study was to develop a new method for co-crystal preparation which adhered to green chemistry principles, and provided advantages over conventional methods. A novel, solvent-free, high-power ultrasound (US) technique, for preparing co-crystals from binary systems, was chosen as the technology which could fulfil these aims. The application of this technology for solid state co-crystal preparation was explored for ibuprofen-nicotinamide (IBU-NIC), carbamazepine-nicotinamide (CBZ-NIC) and carbamazepine-saccharin (CBZ-SAC) co-crystals. The effect of different additives and processing parameters such as power level, temperature and sonication time on co-crystallisation was investigated. Characterisation was carried out using DSC, PXRD, FTIR, Raman and HPLC. In addition, an NIR prediction model was developed and combined with multivariate analysis (PLS) and chemometric pre-treatments. It was found to be a robust, reliable and rapid method for the determination of co-crystal purity for the IBU-NIC and CBZ-NIC pairs. Co-crystal quantification of US samples helped to optimise the US method. Finally, a model formulation of paracetamol containing 5% and 10% PEG 8000 was ultrasonicated at maximum power with different exposure times. A comparison of technological and physicochemical properties of the resulting tablets with those of the tablets obtained using the pressing method evidenced significant differences. This suggested that US energy dissipation (mechanical and thermal effects) was the main mechanism which caused the PAR form I tabletability to improve. It was found that the ultrasound–compacted tablets released the drug at a slower rate compared to pure PAR. This technique was shown to be useful for improving tabletability for low-compressible drugs without the need to use a conventional tabletting machine.
26

Intra-nucleus accumbens shell injections of R(+)- and S(-)- baclofen bidirectionally alter binge-like ethanol, but not saccharin, intake in C57Bl/6J mice

Kasten, Chelsea Rae January 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / It has been proposed that the GABAB receptor subtype plays a role in alcoholism and alcohol use disorders (AUDs) (Cousins et al., 2002; Agabio et al., 2012). Specifically, the GABAB agonist baclofen has been looked at extensively in clinical and pre-clinical studies. In various animal models of chronic and intermittent consumption, baclofen has been shown to both increase (Petry, 1997; Smith et al., 1999; Czachowski et al., 2006; Moore et al., 2007) and decrease (Colombo et al., 2000; 2002; 2005; Stromberg, 2004; Moore et al., 2009) drinking. A critical issue in determining pharmacological effects of a drug is using the appropriate animal model. The drinking-in-the-dark (DID) model, developed by Rhodes et al. (2005, 2007), produces high levels of drinking in a binge-like paradigm and has been used to assess many pharmacological targets (e.g. Kamdar et al., 2007; Gupta et al., 2008; Moore et al., 2007; 2009). While DID produces high-levels of binge drinking, it is unclear what areas of the brain are involved in this behavior. A direct way to target areas that are believed to be involved in the circuitry of particular behaviors is through microinjection of drugs (Kiianmaa et al., 2003). Of particular recent interest involving motivated behaviors and addiction is the nucleus accumbens (Acb) (Everitt & Robbins, 2005); specifically the accumbens shell (AcbSh) (e.g. Rewal et al., 2009, 2012; Nie et al., 2011; Leriche et al., 2008). The current study aimed to investigate the role of GABAB receptors in the AcbSh by examining the ability of two different enantiomers of baclofen to alter ethanol and saccharin intake in male C57BL/6J (B6) mice. B6 mice underwent bilateral cannulation surgery targeting the AcbSh. After 48 hours of recovery time, animals began a five day Drinking-in-the-Dark (DID) procedure where they received 20% ethanol or 0.2% saccharin for two hours, three hours into the dark cycle, each day. Throughout the five drinking sessions, animals were kept in home-cage locomotor activity chambers to monitor activity throughout the drinking cycle. Day 4 drinking was immediately preceded by a mock microinjection, whereas Day 5 drinking was immediately preceded by a drug microinjection. Microinjection of one of five doses of baclofen was given in ng/side dissolved in 200 µl of aCSF (aCSF alone, 0.02 R(+)-, 0.04 R(+)-, 0.08 S(-)-, or 0,16 S(-)-). Intake was recorded every twenty minutes on Days 4 and 5. Retro-orbital sinus blood samples were taken from ethanol animals immediately following the Day 5 drinking period to determine blood ethanol concentrations (BECs). A one-way ANOVA on total Day 4 ethanol consumption revealed no baseline differences between dose groups. A one-way ANOVA on total Day 5 ethanol consumption revealed that the 0.04 R(+)- baclofen dose reduced total drinking, but the 0.16 S(-)- baclofen dose increased total drinking (p’s<0.05). This pattern was reflected in the BECs; 0.04 R(+)- baclofen reduced BECs, whereas 0.16 S(-)- baclofen increased BECs (p’s<0.05). These results were also time-dependent, with R(+)-baclofen reducing drinking in the first 20 minutes of the session and S(-)- increasing drinking in the last 40 minutes of the session. There were no effects on saccharin intake. An issue with the locomotor activity boxes led to unreliable locomotor activity counts. However, because there were no drug effects on saccharin consumption, it was concluded that locomotor effects did not contribute to the decreases or increases in ethanol consumption. These results further implicate the role of GABAB receptors in modulating ethanol intake. The bidirectional effects shown highlight the importance of considering enantioselective drug effects when interpreting data. Finally, these results also support previous conclusions that the AcbSh plays an important role in modulating use of drugs of abuse, but not other reinforcers.

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