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You searched for +publisher:"Universidade Federal de Minas Gerais" +contributor:("Bartira Rossi Bergmann"). Showing records 1 – 2 of 2 total matches.

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1. Patricia Silveira Martins. Mecanismos envolvidos no aumento da concentração plasmática de Sb a partir das composições de antimoniato de meglumina com ciclodextrina, visando o tratamento oral das leishmanioses.

Degree: 2007, Universidade Federal de Minas Gerais

Meglumine antimoniate (MA), complex of pentavalent antimony (Sb(V)) with Nmethyl-D-glucamine (NMG), is currently an agent of choice for the treatment of leishmaniases. This compound is considered inactive when given enterally and is subject to rapid renal clearance after parenteral administration, requiring a multiple dosing regimen. Recently, it was reported that the association of MA to ß-cyclodextrin (ß-CD) enhances the oral absorption of Sb and renders this drug active by the oral route in a model of cutaneous leishmaniasis. However, since MA is highly water-soluble and, most probably, does not interact with the internal hydrophobic cavity of ß-CD, the mechanism responsible for the enhanced oral absorption of Sb in the MA/ß-CD composition is expected to differ from that involved in conventional inclusion drug/ß-CD complexes. The main objective of the present thesis was to investigate the mode of action of the MA/ß-CD composition. For that, MA and the MA/ß-CD composition were physicochemically characterized and their oral absorption in mice and their permeation across a lipid bilayer model were investigated. Since the preparation of MA/ß-CD composition consists in a two-step process, involving the heating of an equimolar MA +ß-CD mixture at 55 °C for 48 h followed by the freeze-drying of the mixture, the effects of heating and of freeze-drying on the physicochemical characteristics of the resulting composition were evaluated. Osmolarity measurements and ESI mass spectrometry analyses of aqueous MA solutions and equimolar MA/ß-CD mixture indicated that the heating step induces the dissociation of MA into species of low molecular weight (1:1Sb-NMG complex) and the formation of ternary NMG-Sb-ß-CD complexes. Circular dichroism and ESI mass spectrometric analyses showed that the freeze-drying step promotes multiple associations between MA and ß-CD, including the formation of (NMG-Sb)2-ß-CD and (NMG-Sb-CD)2 complexes. Oral absorption of Sb in mice from MA+ß-CD physical mixture, heated MA/ß-CD and heated and freeze-dried MA/ß-CD indicated that the heating process increases by less than 2-fold Sb concentration in the serum of mice, while the freeze-drying step enhances significantly by 2- to 3-fold the Sb level. A lipid bilayer model, consisting of glutathione (GSH)-containing liposomes made from phosphatidylcholine, was developed in order to evaluate the permeation of Sb(V) across the lipid bilayer. This model allowed the determination of the permeability coefficient of antimoniate. Its value was found to be equal to 0.82 x 10-10 cm s-1, which is close to the value reported for Cl- ion. The comparison between the permeation rates of MA and of MA/ß-CD composition did not show significant difference under the conditions of concentration and temperature used in this model. A circular dichroism experiment indicated that the MA/ß-CD composition acts as a sustained release system of the antimonial drug, MA. Since cyclodextrins are poorly digested in the small intestine, the association of MA with ß-CD may change the drug… Advisors/Committee Members: Frederic Jean Georges Frezard, Tania Maria de Almeida Alves, Frederic Jean Georges Frezard, Miriam Teresa Paz Lopes, Marcelo Matos Santoro, Bartira Rossi Bergmann.

Subjects/Keywords: Leishmaniose Teses.; Tratamento parenteral Teses.

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Martins, P. S. (2007). Mecanismos envolvidos no aumento da concentração plasmática de Sb a partir das composições de antimoniato de meglumina com ciclodextrina, visando o tratamento oral das leishmanioses. (Thesis). Universidade Federal de Minas Gerais. Retrieved from http://hdl.handle.net/1843/MCSC-7C6T5Y

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Martins, Patricia Silveira. “Mecanismos envolvidos no aumento da concentração plasmática de Sb a partir das composições de antimoniato de meglumina com ciclodextrina, visando o tratamento oral das leishmanioses.” 2007. Thesis, Universidade Federal de Minas Gerais. Accessed November 24, 2020. http://hdl.handle.net/1843/MCSC-7C6T5Y.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Martins, Patricia Silveira. “Mecanismos envolvidos no aumento da concentração plasmática de Sb a partir das composições de antimoniato de meglumina com ciclodextrina, visando o tratamento oral das leishmanioses.” 2007. Web. 24 Nov 2020.

Vancouver:

Martins PS. Mecanismos envolvidos no aumento da concentração plasmática de Sb a partir das composições de antimoniato de meglumina com ciclodextrina, visando o tratamento oral das leishmanioses. [Internet] [Thesis]. Universidade Federal de Minas Gerais; 2007. [cited 2020 Nov 24]. Available from: http://hdl.handle.net/1843/MCSC-7C6T5Y.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Martins PS. Mecanismos envolvidos no aumento da concentração plasmática de Sb a partir das composições de antimoniato de meglumina com ciclodextrina, visando o tratamento oral das leishmanioses. [Thesis]. Universidade Federal de Minas Gerais; 2007. Available from: http://hdl.handle.net/1843/MCSC-7C6T5Y

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

2. Denise Fonseca Cortes. Infecções com baixas doses de Leishmania amazonensis: um modelo para o estudo de leishmania tegumentar americana.

Degree: 2008, Universidade Federal de Minas Gerais

Um modelo de infecção com L. amazonensis na pele, com baixa dose (103) de parasitos, é comparado à infecção com alta dose (106) de L. amazonensis e baixa e alta dose de L. major. Camundongos C57BL/6 foram infectados com 103 ou 106 parasitos na orelha e o curso de infecção foi acompanhado. O surgimento de lesões em camundongos infectados com 103 parasitos foi mais lento, quando comparado aos camundongos infectados com 106 Leishmania e parasitos foram detectados no sítio de infecção mesmo antes do surgimento das lesões. Camundongos infectados com L. amazonensis apresentaram lesões persistentes, enquanto a infecção com L. major curou espontaneamente em ambos os grupos, apesar de linfócitos persistirem no sítio de infecção, mesmo depois da cura. Macrófagos persistiram apenas nos camundongos infectados com L. amazonensis. Camundongos infectados com este parasito produziram níveis mais baixos de IFN- que os camundongos infectados com L. major. Nenhuma correlação entre persistência do parasito e níveis de IL-10 ou produção de óxido nítrico ou atividade de arginase por macrófagos foi encontrada. Concluiu-se que a infecção com baixa dose de L amazonensis na derme alterou o curso de infecção atrasando o surgimento da lesão, mas não alterou o fenótipo de suscetibilidade e produção de citocinas descritas após infecção subcutânea com alto número de parasitos.

A model of infection with Leishmania amazonensis in the skin, with low doses of parasites, was compared to infection with high doses of L. amazonensis and low and high doses of L. major. C57BL/6 mice were infected with 103 or 106 parasites in the ear and the outcome of infection was assessed. The appearance of lesions in mice infected with 103 parasites was delayed compared to mice infected with 106 Leishmania and parasites were detectable at the infection site even before lesions were. Mice infected with L. amazonensis displayed persistent lesions, while infection with L. major spontaneously healed in all groups, albeit lymphocytes persisted at the site of infection even after healing. Macrophages persisted only in L. amazonensis-infected mice. L. amazonensis infected mice produced lower levels of IFN-ã than mice infected with L. major. No correlation between persistence of parasites and IL-10 levels or the production of nitric oxide or activity of arginase by macrophages was found. We conclude that infection with low doses of L. amazonensis in the dermis changes the course of infection by delaying the appearance of lesions, but does not change the outcome of susceptibility and cytokine production described for the subcutaneous infection with high numbers of parasites.

Advisors/Committee Members: Leda Quercia Vieira, Luis Carlos Crocco Afonso, Leda Quercia Vieira, Luis Carlos Crocco Afonso, Kenneth John Gollob, Ana Paula Salles Moura Fernandes, Milton Adriano Pelli de Oliveira, Bartira Rossi Bergmann.

Subjects/Keywords: Bioquímica Teses.; Leishmania amazonensis Teses.; Leishmaniose visceral americana Teses

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Cortes, D. F. (2008). Infecções com baixas doses de Leishmania amazonensis: um modelo para o estudo de leishmania tegumentar americana. (Thesis). Universidade Federal de Minas Gerais. Retrieved from http://hdl.handle.net/1843/UCSD-8HENY7

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Cortes, Denise Fonseca. “Infecções com baixas doses de Leishmania amazonensis: um modelo para o estudo de leishmania tegumentar americana.” 2008. Thesis, Universidade Federal de Minas Gerais. Accessed November 24, 2020. http://hdl.handle.net/1843/UCSD-8HENY7.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Cortes, Denise Fonseca. “Infecções com baixas doses de Leishmania amazonensis: um modelo para o estudo de leishmania tegumentar americana.” 2008. Web. 24 Nov 2020.

Vancouver:

Cortes DF. Infecções com baixas doses de Leishmania amazonensis: um modelo para o estudo de leishmania tegumentar americana. [Internet] [Thesis]. Universidade Federal de Minas Gerais; 2008. [cited 2020 Nov 24]. Available from: http://hdl.handle.net/1843/UCSD-8HENY7.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Cortes DF. Infecções com baixas doses de Leishmania amazonensis: um modelo para o estudo de leishmania tegumentar americana. [Thesis]. Universidade Federal de Minas Gerais; 2008. Available from: http://hdl.handle.net/1843/UCSD-8HENY7

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

.