Thesis (Ph.D.) -- Virginia Commonwealth University, 2005. / Title from title-page of electronic thesis. Prepared for: Dept. of Pharmaceutics. Bibliography: p. 180-196.

Orientador: Nelson Eduardo Durán Caballero / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-25T19:26:39Z (GMT). No. of bitstreams: 1 Silva_JeaniferCaverzan_M.pdf: 3206387 bytes, checksum: 2e1b76efef3afb5141bea5a703a092d6 (MD5) Previous issue date: 2014 / Resumo: A alopecia é uma doença caracterizada pela diminuição ou ausência de cabelos e/ou pelos, que gera estresse emocional para milhões de homens e mulheres no mundo. O tratamento da alopecia é realizado, em geral, com aplicação tópica de medicamentos como o 17-alfa-estradiol, que é um estereoisômero do hormônio sexual 17-beta-estradiol. Entretanto este fármaco, assim como outros utilizados no tratamento de alopecia, apresentam baixa eficácia. Para tentar reverter essa situação, a associação deste fármaco com sistemas de liberação sustentada pode aumentar a sua eficácia e reduzir os efeitos colaterais. Desta forma, o objetivo deste trabalho foi o desenvolvimento e a caracterização físico-química e biológica de carreadores lipídicos nanoestruturados (CLN) no encapsulamento de estradiol visando aumentar a eficácia deste fármaco no tratamento de alopecia. Os CLN foram preparados pelo método de microemulsão à quente/sonicação, e foram caracterizados quanto ao diâmetro e potencial Zeta, utilizando-se as técnicas de espectroscopia de correlação de fótons e mobilidade eletroforética respectivamente, sendo o diâmetro médio obtido no valor de 96 ± 15 nm e o potencial zeta médio foi de -16 ± 6 mV. A eficiência de encapsulamento (EE) do 17-alfa-estradiol avaliada por cromatografia líquida/fluorescência foi de 99,6 ± 0,3%. No estudo de estabilidade física dos CLN armazenados em temperatura ambiente foi observado que após dois meses os parâmetros de diâmetro, potencial Zeta, pH, EE e índice de recristalização (IR) não sofreram alterações significativas, demonstrando que a formulação de CLN desenvolvida neste projeto tem grande potencial como sistema de liberação do 17-alfa-estradiol. O poder de penetração cutânea dos CLN foi avaliado em célula de difusão de Franz e microscopia confocal, sendo que os resultados indicam que há acumulo dos CLN nas porções mais externas da epiderme, o que sugere que esta formulação está dentro dos padrões de biossegurança, principalmente no folículo piloso, sítio de ação do fármaco. Além disso, as avaliações de internalização dos CLN em células de queratinócitos demonstraram que os nanocarreadores foram internalizados e acumularam-se principalmente em seu citoplasma / Abstract: Alopecia is a disease characterized by decreased or absent hair, which creates emotional stress for millions of men and women worldwide. The treatment of alopecia is carried out usually with topical application of drugs such as, sex hormone. However, this drug as well as others used in the treatment of alopecia have low efficacy. In this way the association of this drug with sustained delivery systems may increase the efficacy and reduce side effects. Thus, the aim of this work is the development and physico-chemical characterization of nanostructured lipid carriers (NLC) in the encapsulation of a steroid, aiming to increase the effectiveness of this drug in the treatment of alopecia. NLCs were prepared by the microemulsion of hot sonication method. The diameter and zeta potential were characterized , by using the technique of photon correlation spectroscopy and the average diameter obtained was 96 ± 15 nm while the average zeta potential was -16 ± 6mV. The encapsulation efficiency (EE) of the steroid measured by liquid chromatography with fluorescence detection was 99.6 ± 0.3%. In the study of physical stability of CLN stored at room temperature was observed that after two months the parameters diameter , zeta potential , pH , EE and recrystallization index (RI ) did not change significantly , demonstrating that this project has developed CLN great potential as a delivery system of 17-alpha- estradiol. The power dermal penetration of CLN was evaluated in Franz diffusion cell and confocal microscopy, and the results indicate that there is accumulation of CLN in the outer portions of the epidermis, especially the hair follicle, suggesting that this formulation is within the standards of biosecurity. Furthermore, evaluations of internalization of CLN on keratinocytes cells demonstrated that nanocarriers were internalized and accumulated mainly in the cytoplasm / Mestrado / Físico-Química / Mestra em Química

Targeting is a skill that involves the accurate projection of an object to a target; this requires accurate integration of visual information with spatial and motor skills. Targeting tasks demonstrate a consistent male advantage. Contrary to popular belief, this male advantage is not accounted for by participants throwing experience or their size. The factors that mediate or account for the sex difference observed in targeting accuracy have not yet been identified. This dissertation addresses issues following from two prominent theories that attempt to explain this sex difference. The first theory proposes that the male advantage on targeting accuracy is due to the tasks proxemic and/or motoric characteristics, whereas the second theory proposes that the sex difference in targeting accuracy is due to differential exposure to androgenic or estrogenic sex hormone concentrations. The first and second studies in this dissertation follow from the first theory, examining whether changing the motoric or proxemic characteristics of targeting tasks will mediate the sex difference. The third study is related to the second theory; it examines the relations among direct and indirect measures of prenatal and circulating sex hormone concentrations and targeting accuracy within samples of men and women. Collectively the results from studies 1 and 2 indicate that the proxemic and motoric characteristics are related to the sex difference on targeting tasks; specifically, targeting tasks must involve only fine motor movements and be performed in intrapersonal space in order for the male advantage to be negated.<p>The results from study 3 indicate that men who were exposed to relatively high prenatal testosterone concentrations and continue to have relatively high circulating testosterone concentrations perform less accurately on targeting tasks than do all other groups of men. The results from study 3 also indicate that women exposed to relatively high prenatal testosterone concentrations target significantly more accurately than women that were exposed to relatively low prenatal testosterone concentrations. As well, the results showed that women who use oral contraceptives target significantly more accurately when they are not currently taking the exogenous estrogen supplements (menstrual phase) than when they are taking the supplements (midluteal phase). These results are discussed in light of the two prominent theories explaining the sex difference in targeting accuracy. A synthesized theory is proposed, and directions for future research are discussed.

Targeting is a skill that involves the accurate projection of an object to a target; this requires accurate integration of visual information with spatial and motor skills. Targeting tasks demonstrate a consistent male advantage. Contrary to popular belief, this male advantage is not accounted for by participants throwing experience or their size. The factors that mediate or account for the sex difference observed in targeting accuracy have not yet been identified. This dissertation addresses issues following from two prominent theories that attempt to explain this sex difference. The first theory proposes that the male advantage on targeting accuracy is due to the tasks proxemic and/or motoric characteristics, whereas the second theory proposes that the sex difference in targeting accuracy is due to differential exposure to androgenic or estrogenic sex hormone concentrations. The first and second studies in this dissertation follow from the first theory, examining whether changing the motoric or proxemic characteristics of targeting tasks will mediate the sex difference. The third study is related to the second theory; it examines the relations among direct and indirect measures of prenatal and circulating sex hormone concentrations and targeting accuracy within samples of men and women. Collectively the results from studies 1 and 2 indicate that the proxemic and motoric characteristics are related to the sex difference on targeting tasks; specifically, targeting tasks must involve only fine motor movements and be performed in intrapersonal space in order for the male advantage to be negated.<p>The results from study 3 indicate that men who were exposed to relatively high prenatal testosterone concentrations and continue to have relatively high circulating testosterone concentrations perform less accurately on targeting tasks than do all other groups of men. The results from study 3 also indicate that women exposed to relatively high prenatal testosterone concentrations target significantly more accurately than women that were exposed to relatively low prenatal testosterone concentrations. As well, the results showed that women who use oral contraceptives target significantly more accurately when they are not currently taking the exogenous estrogen supplements (menstrual phase) than when they are taking the supplements (midluteal phase). These results are discussed in light of the two prominent theories explaining the sex difference in targeting accuracy. A synthesized theory is proposed, and directions for future research are discussed.

Ulm, Univ., Diss., 2007.

Thesis (M.S.)--Eastern Illinois University, 2008. / Includes bibliographical references (leaves 69-79).

Thesis (Ph. D.)--University of Hawaii at Manoa, 2000. / Includes bibliographical references (leaves 184-198). Also available on microfiche.

Thesis (M.S.)--University of Michigan, 1987.

Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Includes bibliographical references (leaves 177-191). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Includes bibliographical references (leaves 177-191). Also available on the Internet.