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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

Topical therapy with novel targeted releasing formulations

Luo, E-Ching January 2015 (has links)
Aims Novel low toxicity formulations using biomaterial (i.e. gelatin) for triggered release and controlled manner of formulated therapeutic agent for treatment of immuno-inflammatory disease on the skin were studied in the PhD project. It is a challenging concept because of difficulties in targeting and controlling for the releases that is tailored to disease severity or lesional inflammation extent. Background Psoriasis is a complicated disease with multi-factorial pathogenesis. Potent anti-psoriatic drugs are available but for managing the symptoms of the disease. Due to the toxicity of the therapeutic agents, different strategies have been suggested to avoid severe side effects from long term or high dose usage. Psoriasis is an optimal representative for this investigation in terms of the toxicities of recognized drugs, unpredictable or relapsed nature of the disease or even life threatening developments if generalised symptoms develop as they can in some types. Method Using the rheometry in temperature sweep mode, a series of concentrations of pure gelatin and gelatin mixture were developed. In addition, using tryptic enzyme, their action was studied rheologically. A Petri dish observational method was used to investigate the permeability of formulations chosen on the basis of the rheometric performance. Then, combining the Copley diffusion cell kit and UV/VIS spectrophotometer, the release of the model drug was investigated in porous artificial membranes and porcine skin for one or more of the formulations. The preliminary part using porous artificial membranes was to investigate the amount of the release of tartrazine from a candidate gel into the circulation system. In this part, alternatives were considered for dealing with gelatin or gelatin/carbomer swelling by using mechanical stress approach or changing to octanol solvent. For the latter a dye, rhodamine, which would partition into octanol had to be substituted for tartrazine (which has iv negligible organic solubility). In the final part, using skin membrane, the amount of the release tartrazine to the skin was measured because in this, skin staining, rather than partition was needed. Results Promising results were observed in each stage. The rheological investigation on the developed gelatin/water system and gelatin/carbomer intimate system in absence and presence of tryptic enzyme showed that a responsive but convenient formulation was possible and was independent of the presence of tartrazine. Analysis of these resulting rheological profiles suggested a prediction for the best gelatin/carbomer formulations to select for the permeability tests. The latter used Petri dishes to compare differential diffusion of these candidates showed the carbomer was able to stop three-dimensional spreading of the dye through the pure gelatin or its residue (after enzyme action). The drug release studies using artificial porous membranes for preliminary work showed significant differential release between enzyme free and enzyme treated versions of the 20% gelatin/0.9% carbomer formulation. The final success was the in vitro skin experiment in which the result was obtained for the pure gelatin and shown to deliver very substantially more to areas with applied enzyme s a simulated lesion.
2

Desenvolvimento de gel de absorção percutânea contendo estradiol

Silveira, Airton Monza da January 1994 (has links)
A reposição estrogênica na pós-menopausa revela-se através de benefícios na melhora da qualidade de vida, prevenção e cura da osteoporose, bem como na diminuição da incidência de doenças cardiovasculares. A via percutânea apresenta grande interesse devido a fatores como, manutenção de níveis plasmáticos e eliminação da primeira passagem hepática, responsável pelo surgimento de efeitos colaterais adversos, aliados a relativa simplicidade de desenvolvimento e produção, facilidade na aplicação e versatilidade. Neste trabalho foram viabilizadas formulações de géis hidroalcoólicos contendo estradiol com diferentes bases, adaptando e desenvolvendo metodologias para determinação de características físicas, químicas e tecnológicas, como espalhabilidade, consistência, liodisponibilidade, teor da substância ativa e conservantes, bem como ensaios preliminares de penetração na pele, e em membranas artificiais e de estabilidade física e química de estradiol e dos conservantes. Verificou-se que dois dos gíss desenvolvidos, com bases de carbômero (Carbopol 940®) e hidroxietilcelulose (Cellosize QP 100®), apresentaram características apropriadas no que diz respeito a consistência, espalhabilidade e promoção da penetração de estradiol através da pele. Esta foi avaliada através do desenvolvimento ponderal uterino de ratas castradas e determinação dos níveis séricos de estradiol por fluorimunoensaio, não havendo diferença significativa entre os produtos neste ensaio. Ambas as formulações mostraram-se estáveis fisicamente, porém, o produto desenvolvido com base de hidroxietilcelulose apresentou degradação significativa de estradiol. Os ensaios de absorção de estradiol em membranas artificiais não diferenciou significativamente as formulações quanto ao tipo de base e tempo de exposição, observou-se entretanto, que existe uma relação entre a quantidade aplicada de gel e de estradiol absorvido. / The hormonal replacement therapy for menopausal symptoms intents the healing and prevention of osteoporosis, the decrease of the incidence of cardiovascular diseases as well the improvement of life quality, affording relief from any of a long list of subjective complaints. The election of a transdermal estradiol formulation is due to its abilities to bypass the liver resulting adequate hormonal plasmatic levels. In addition, it is considerably simple to manufacture and to adapt to individual dosages. This research aims the formulation of estradiol as an hydroalcoholic gel using different gelformers. The development and adaptation of methodologies to perform the physical, chemical and biological characterization of the formulated products were also realized. Two of the formulated gels showed appropriate characteristics of consistence, spreading and skin permeation. They were prepared with carbomer (Carbopol 940) and hydroxiethylcellulose (Cellosize QP 100). Biological evaluation was performed by the essay of the uterusweight of castrated rats and by immunofluorescence assay. The statistical analysis showed no differences between the methods and gels. The stability test for the two formulations yielded good physical stability results but the hydroxyethylcellulose gel showed significant estradiol degradation. Although the gels artificial membrane absorptions didn't differ when submeted to difference contact times, it was detected a kind of relationship between the applied gel amount and the absorbed estradiol.
3

Skystų oftalmologinių sistemų modeliavimas / Ophthalmic liquid systems design

Jarošaitė, Roberta 18 June 2014 (has links)
Darbo tikslas – sumodeliuoti skystą oftalmologinę hidrofilinę sistemą su numatytais fizikocheminiais rodikliais ir įvertinti modelinės medžiagos – natrio diklofenako atpalaidavimą biofarmaciniu metodu in vitro. / Objective of work: to design liquid hydrophilic ophthalmic system with provided physicochemical characteristics and determine the release of the model material - sodium diclofenac in vitro.
4

Desenvolvimento de gel de absorção percutânea contendo estradiol

Silveira, Airton Monza da January 1994 (has links)
A reposição estrogênica na pós-menopausa revela-se através de benefícios na melhora da qualidade de vida, prevenção e cura da osteoporose, bem como na diminuição da incidência de doenças cardiovasculares. A via percutânea apresenta grande interesse devido a fatores como, manutenção de níveis plasmáticos e eliminação da primeira passagem hepática, responsável pelo surgimento de efeitos colaterais adversos, aliados a relativa simplicidade de desenvolvimento e produção, facilidade na aplicação e versatilidade. Neste trabalho foram viabilizadas formulações de géis hidroalcoólicos contendo estradiol com diferentes bases, adaptando e desenvolvendo metodologias para determinação de características físicas, químicas e tecnológicas, como espalhabilidade, consistência, liodisponibilidade, teor da substância ativa e conservantes, bem como ensaios preliminares de penetração na pele, e em membranas artificiais e de estabilidade física e química de estradiol e dos conservantes. Verificou-se que dois dos gíss desenvolvidos, com bases de carbômero (Carbopol 940®) e hidroxietilcelulose (Cellosize QP 100®), apresentaram características apropriadas no que diz respeito a consistência, espalhabilidade e promoção da penetração de estradiol através da pele. Esta foi avaliada através do desenvolvimento ponderal uterino de ratas castradas e determinação dos níveis séricos de estradiol por fluorimunoensaio, não havendo diferença significativa entre os produtos neste ensaio. Ambas as formulações mostraram-se estáveis fisicamente, porém, o produto desenvolvido com base de hidroxietilcelulose apresentou degradação significativa de estradiol. Os ensaios de absorção de estradiol em membranas artificiais não diferenciou significativamente as formulações quanto ao tipo de base e tempo de exposição, observou-se entretanto, que existe uma relação entre a quantidade aplicada de gel e de estradiol absorvido. / The hormonal replacement therapy for menopausal symptoms intents the healing and prevention of osteoporosis, the decrease of the incidence of cardiovascular diseases as well the improvement of life quality, affording relief from any of a long list of subjective complaints. The election of a transdermal estradiol formulation is due to its abilities to bypass the liver resulting adequate hormonal plasmatic levels. In addition, it is considerably simple to manufacture and to adapt to individual dosages. This research aims the formulation of estradiol as an hydroalcoholic gel using different gelformers. The development and adaptation of methodologies to perform the physical, chemical and biological characterization of the formulated products were also realized. Two of the formulated gels showed appropriate characteristics of consistence, spreading and skin permeation. They were prepared with carbomer (Carbopol 940) and hydroxiethylcellulose (Cellosize QP 100). Biological evaluation was performed by the essay of the uterusweight of castrated rats and by immunofluorescence assay. The statistical analysis showed no differences between the methods and gels. The stability test for the two formulations yielded good physical stability results but the hydroxyethylcellulose gel showed significant estradiol degradation. Although the gels artificial membrane absorptions didn't differ when submeted to difference contact times, it was detected a kind of relationship between the applied gel amount and the absorbed estradiol.
5

Desenvolvimento de gel de absorção percutânea contendo estradiol

Silveira, Airton Monza da January 1994 (has links)
A reposição estrogênica na pós-menopausa revela-se através de benefícios na melhora da qualidade de vida, prevenção e cura da osteoporose, bem como na diminuição da incidência de doenças cardiovasculares. A via percutânea apresenta grande interesse devido a fatores como, manutenção de níveis plasmáticos e eliminação da primeira passagem hepática, responsável pelo surgimento de efeitos colaterais adversos, aliados a relativa simplicidade de desenvolvimento e produção, facilidade na aplicação e versatilidade. Neste trabalho foram viabilizadas formulações de géis hidroalcoólicos contendo estradiol com diferentes bases, adaptando e desenvolvendo metodologias para determinação de características físicas, químicas e tecnológicas, como espalhabilidade, consistência, liodisponibilidade, teor da substância ativa e conservantes, bem como ensaios preliminares de penetração na pele, e em membranas artificiais e de estabilidade física e química de estradiol e dos conservantes. Verificou-se que dois dos gíss desenvolvidos, com bases de carbômero (Carbopol 940®) e hidroxietilcelulose (Cellosize QP 100®), apresentaram características apropriadas no que diz respeito a consistência, espalhabilidade e promoção da penetração de estradiol através da pele. Esta foi avaliada através do desenvolvimento ponderal uterino de ratas castradas e determinação dos níveis séricos de estradiol por fluorimunoensaio, não havendo diferença significativa entre os produtos neste ensaio. Ambas as formulações mostraram-se estáveis fisicamente, porém, o produto desenvolvido com base de hidroxietilcelulose apresentou degradação significativa de estradiol. Os ensaios de absorção de estradiol em membranas artificiais não diferenciou significativamente as formulações quanto ao tipo de base e tempo de exposição, observou-se entretanto, que existe uma relação entre a quantidade aplicada de gel e de estradiol absorvido. / The hormonal replacement therapy for menopausal symptoms intents the healing and prevention of osteoporosis, the decrease of the incidence of cardiovascular diseases as well the improvement of life quality, affording relief from any of a long list of subjective complaints. The election of a transdermal estradiol formulation is due to its abilities to bypass the liver resulting adequate hormonal plasmatic levels. In addition, it is considerably simple to manufacture and to adapt to individual dosages. This research aims the formulation of estradiol as an hydroalcoholic gel using different gelformers. The development and adaptation of methodologies to perform the physical, chemical and biological characterization of the formulated products were also realized. Two of the formulated gels showed appropriate characteristics of consistence, spreading and skin permeation. They were prepared with carbomer (Carbopol 940) and hydroxiethylcellulose (Cellosize QP 100). Biological evaluation was performed by the essay of the uterusweight of castrated rats and by immunofluorescence assay. The statistical analysis showed no differences between the methods and gels. The stability test for the two formulations yielded good physical stability results but the hydroxyethylcellulose gel showed significant estradiol degradation. Although the gels artificial membrane absorptions didn't differ when submeted to difference contact times, it was detected a kind of relationship between the applied gel amount and the absorbed estradiol.
6

Investigation of drug ionic liquid salts for topical delivery systems

Bansiwal, Mukesh January 2017 (has links)
Pharmaceutical companies and FDA (Federal Drug Administration) rules rely heavily on crystalline active pharmaceutical ingredients delivered as tablets and powders in the form of neutral compounds, salts and solvates of neutral compounds and salts. About half of all drugs sold in the market are in the form of salts which are held together by ionic bonds along with some other forces. Recently, Ionic liquids (ILs) an interesting class of chemical compounds have offered potential opportunity for exploration as novel drug ionic liquid salts, particularly in the field of transdermal/topical drug delivery. Due to the multifunctional nature of these salts they could allow generation of new pathway to manipulate the transport and deposition behaviour of the drug molecule. It is this modular approach of IL that forms the basis of the research presented here, in which pharmaceutically acceptable compounds are combined with selected drugs with known problems. IL salts were generated by combining at least one drug molecule with FDA approved compounds and were assessed for physicochemical properties, skin deposition and permeation studies. Skin deposition data suggested that these systems exhibit high skin retention, which was found to correlate with the molecular weight. On the other hand, permeation data displayed an inverse relationship between flux values and molecular weight of the permeant. Similar work was extended with ILs with mixed anions containing two drugs. The benzalkonium-sulfacetamide ILs were investigated for synergism and the biological studies data display no synergistic effect. It was also illustrated that in-situ IL based ibuprofen hydrogels systems could be manipulated via IL approach for topical application. These findings suggest the potential applicability of IL based formulations for topical delivery of drugs.
7

APLICABILIDADE DO CIMENTO DE CARBÔMERO DE VIDRO NO TRATAMENTO RESTAURADOR ATRAUMÁTICO: AVALIAÇÃO LABORATORIAL E CLÍNICA

Lopes, Célia Maria Condeixa de França 02 March 2018 (has links)
Submitted by Angela Maria de Oliveira (amolivei@uepg.br) on 2018-04-20T13:32:57Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Celia Maria Condeixa.pdf: 3318245 bytes, checksum: b05218ee22f88d71aa7b78f5481c7aa6 (MD5) / Made available in DSpace on 2018-04-20T13:32:57Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Celia Maria Condeixa.pdf: 3318245 bytes, checksum: b05218ee22f88d71aa7b78f5481c7aa6 (MD5) Previous issue date: 2018-03-02 / O objetivo desta pesquisa foi avaliar o desempenho laboratorial e clínico do cimento de carbômero de vidro utilizado no tratamento restaurador atraumáticopor meio de dois estudos laboratoriais, uma revisão sistemática com meta-análise e um ensaio clínico randomizado. O estudo 1avaliou a microdureza de dois cimentos de ionômero de vidro – cimento de carbômero de vidro (GCP Glass Fill, GCP-Dental) e um cimento de ionômero de vidro modificado por resina (Riva Light Cure, SDI) ‒ em combinação com quatro unidades fotopolimerizadoras (Carbo LED lamp, GCP-Dental; Demi LED curing light, Kerr; Poli Wireless, Kavo; Radii Plus, SDI). O estudo 2analisou a liberação/recarga de flúor e a rugosidade superficial do cimento de carbômero de vidro (GCP Glass Fill, GCP-Dental) em comparação a outros cimentos de ionômero vidro (Riva Self Cure, SDI; Riva Light Cure, SDI; Equia Fil, GC Europe) encapsulados. A revisão sistemática foi realizada para responder a pergunta PICO: “Os selantes de cimentos de carbômero de vidro são mais efetivos na prevenção/paralização de lesões cariosas em molares permanentes de crianças quando comparados com outros materiais utilizados como selantes?"O estudo 4comparou a taxa de sobrevivência das restaurações ART classe II em dentes decíduos, realizada com cimento de carbômero de vidro e um cimento de ionômero de vidro de alta viscosidade após 12 meses de acompanhamento clínico. Os resultados do estudo 1 demonstraram que o cimento de carbômero de vidro(GCP Glass Fill, GCPDental) apresentou valor de microdureza significativamente superior quando comparado com o cimento de ionômero de vidro modificado por resina (Riva Light Cure, SDI), independente da unidade fotopolimerizadora utilizada. No estudo 2, os cimentos de ionômero de vidro, incluindo o cimento de carbômero de vidro, apresentaram capacidade de liberação e recarga de flúor e não mostraram aumento de rugosidade superfícial pela aplicação tópica de flúor. Os dados do estudo 3 mostraram que novas lesões cariosastendem a ser inibidas após a colocação de selantes em molares permanentes, tanto pelo cimento de carbômero de vidro como por outros materiais utilizados como selante, após 6 e 12 meses de acompanhamento. A longevidade das restaurações de ART classe II, artigo 4, de cimento de carbômero de vidro foi inferior às restaurações de ionômero de vidro de alta viscosidade em dentes decíduos após 12 meses de acompanhamento clínico. A partir desses resultados, conclui-se que o desempenho laboratorial do cimento de carbômero foi superior ao cimento de ionômero de vidro modificado por resina, em relação a microdureza e em relação a liberação e recarga de flúor e rugosidade superficial foi semelhante aos cimentos de ionômero de vidro,apresentou um desempenho clínico inferior em restaurações ART classe II quando comparado com estes mesmos materiais e que novas lesões cariosas tendem a ser inibidas quando o cimento de carbômero de vidro é utilizado como selante de fossas e fissuras. / The aim of this research was to evaluate the laboratory and clinical performance of glass carbomer cement used in atraumatic restorative treatmentby means of two laboratory studies, a systematic review with metaanalysis and a randomized clinical trial. Study 1 evaluated the microhardness of two glass ionomer cements– glass carbomer (GCP Glass Fill, GCP-Dental) and a resin modified glass ionomer cement (Riva Light Cure, SDI) - in combination with four light curing units (Carbo LED lamp, GCP-Dental, Demi LED curing light, Kerr, Poli Wireless, Kavo, Radii Plus, SDI).Study 2 analyzed the fluoride release/recharge and surface roughness of glass carbomer cement (GCP Glass-Dental, GCP-Dental) compared to other encapsulated glass ionomer cements (Riva Self Cure, SDI; Riva Light Cure, SDI; Equia Fil, GC Europe).The systematic review was performed to answer the PICO question: “Is glass carbomer sealants more efficient in preventing/arresting carious lesions in permanent molars of children when compared to other sealant materials?” Study 4 compared the survival rate of ART Class II restorations in primary teeth, performed with glass carbomer cement and a high viscosity glass ionomer cement after 12 months of follow up.The results of study 1 showed that glass carbomer cement (GCP Glass-Dental, GCPDental) had a significantly higher microhardness value when compared to a resin modified glass ionomer cement (Riva Light Cure , SDI), regardless of the light curing unit used.In study 2, glass ionomer cements, including glass carbomer cement, presented fluoride release and recharge ability and showed no surface roughness increase by topical application of fluoride.The data from study 3 showed that new carious lesions seem to be inhibited after the placement of sealants in permanent molars, both by glass carbomer cement and other materials used as sealant, after 6 and 12 months of follow up.The longevity of glass carbomer ART class II restorations, article 4, was inferior to that of high viscosity glass ionomer restorations after 12 months follow up in primay teeth.From these results, it was concluded that the laboratory performanceof glass carbomer cement was superior to resin-modified glass ionomer cement in relation to microhardness and in relation to fluoride release and recharge and surface roughness was similar to glass ionomer cements, presented a lower clinical performance in class II ART restorations when compared to these same materials and new carious lesions seem to be inhibited when glass carbomer cement is used as pit and fissure sealant.

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