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1.
Mol Pharm ; 21(3): 1272-1284, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38361428

RESUMEN

Rifampicin (RIF) is an antibiotic used to treat tuberculosis and leprosy. Even though RIF is a market-available drug, it has a low aqueous solubility, hindering its bioavailability. Among the strategies for bioavailability improvement of poorly soluble drugs, coamorphous systems have been revealed as an alternative in the increase of the aqueous solubility of drug systems and at the same time also increasing the amorphous state stability and dissolution rate when compared with the neat drug. In this work, a new coamorphous form from RIF and tromethamine (TRIS) was synthesized by slow evaporation. Structural, electronic, and thermodynamic properties and solvation effects, as well as drug-coformer intermolecular interactions, were studied through density functional theory (DFT) calculations. Powder X-ray diffraction (PXRD) data allowed us to verify the formation of a new coamorphous. In addition, the DFT study indicates a possible intermolecular interaction by hydrogen bonds between the available amino and carbonyl groups of RIF and the hydroxyl and amino groups of TRIS. The theoretical spectra obtained are in good agreement with the experimental data, suggesting the main interactions occurring in the formation of the coamorphous system. PXRD was used to study the physical stability of the coamorphous system under accelerated ICH conditions (40 °C and 75% RH), indicating that the material remained in an amorphous state up to 180 days. The thermogravimetry result of this material showed a good thermal stability up to 153 °C, and differential scanning calorimetry showed that the glass temperature (Tg) was at 70.0 °C. Solubility studies demonstrated an increase in the solubility of RIF by 5.5-fold when compared with its crystalline counterpart. Therefore, this new material presents critical parameters that can be considered in the development of new coamorphous formulations.


Asunto(s)
Rifampin , Trometamina , Composición de Medicamentos , Solubilidad , Agua , Modelos Teóricos , Estabilidad de Medicamentos , Rastreo Diferencial de Calorimetría , Difracción de Rayos X
2.
Nature ; 622(7982): 393-401, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37821590

RESUMEN

Recent human decedent model studies1,2 and compassionate xenograft use3 have explored the promise of porcine organs for human transplantation. To proceed to human studies, a clinically ready porcine donor must be engineered and its xenograft successfully tested in nonhuman primates. Here we describe the design, creation and long-term life-supporting function of kidney grafts from a genetically engineered porcine donor transplanted into a cynomolgus monkey model. The porcine donor was engineered to carry 69 genomic edits, eliminating glycan antigens, overexpressing human transgenes and inactivating porcine endogenous retroviruses. In vitro functional analyses showed that the edited kidney endothelial cells modulated inflammation to an extent that was indistinguishable from that of human endothelial cells, suggesting that these edited cells acquired a high level of human immune compatibility. When transplanted into cynomolgus monkeys, the kidneys with three glycan antigen knockouts alone experienced poor graft survival, whereas those with glycan antigen knockouts and human transgene expression demonstrated significantly longer survival time, suggesting the benefit of human transgene expression in vivo. These results show that preclinical studies of renal xenotransplantation could be successfully conducted in nonhuman primates and bring us closer to clinical trials of genetically engineered porcine renal grafts.


Asunto(s)
Rechazo de Injerto , Trasplante de Riñón , Macaca fascicularis , Porcinos , Trasplante Heterólogo , Animales , Humanos , Animales Modificados Genéticamente , Células Endoteliales/inmunología , Células Endoteliales/metabolismo , Rechazo de Injerto/inmunología , Rechazo de Injerto/prevención & control , Trasplante de Riñón/métodos , Polisacáridos/deficiencia , Porcinos/genética , Trasplante Heterólogo/métodos , Transgenes/genética
3.
Am J Transplant ; 22(1): 46-57, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34331749

RESUMEN

Porcine cells devoid of three major carbohydrate xenoantigens, αGal, Neu5GC, and SDa (TKO) exhibit markedly reduced binding of human natural antibodies. Therefore, it is anticipated that TKO pigs will be better donors for human xenotransplantation. However, previous studies on TKO pigs using old world monkeys (OWMs) have been disappointing because of higher anti-TKO pig antibodies in OWMs than humans. Here, we show that long-term survival of renal xenografts from TKO pigs that express additional human transgenes (hTGs) can be achieved in cynomolgus monkeys. Kidney xenografts from TKO-hTG pigs were transplanted into eight cynomolgus recipients without pre-screening for low anti-pig antibody titers. Two recipients of TKO-hTG xenografts with low expression of human complement regulatory proteins (CRPs) (TKO-A) survived for 2 and 61 days, whereas six recipients of TKO-hTG xenografts with high CRP expression (TKO-B) survived for 15, 20, 71, 135, 265, and 316 days. Prolonged CD4+ T cell depletion and low anti-pig antibody titers, which were previously reported important for long-term survival of αGal knock-out (GTKO) xenografts, were not always required for long-term survival of TKO-hTG renal xenografts. This study indicates that OWMs such as cynomolgus monkeys can be used as a relevant model for clinical application of xenotransplantation using TKO pigs.


Asunto(s)
Trasplante de Riñón , Animales , Animales Modificados Genéticamente , Rechazo de Injerto/genética , Humanos , Macaca fascicularis , Porcinos , Trasplante Heterólogo
5.
Cad. Ibero Am. Direito Sanit. (Impr.) ; 6(supl.3): 815-dez. 2017.
Artículo en Portugués | LILACS-Express | LILACS | ID: biblio-1047422

RESUMEN

O presente trabalho apresenta a importância do vínculo com a comunidade e como este fator é essencial na construção de ações em saúde e na melhoria dos serviços perante a população, buscando propiciar mais autonomia a ela e integração dos saberes científico e popular. Trata-se de um estudo descritivo, do tipo relato de experiência, do projeto de extensão intitulado "Saberes e Práticas de Saúde no Contexto de uma Comunidade em Vulnerabilidade Social", desenvolvido no município de Arapiraca-AL, Brasil. Foram realizadas ações na comunidade e ao final de cada ação, foi aberto um espaço de fala para os participantes expressarem suas perspectivas, aprendizados e experiências de vida, demonstrando confiança no compartilhamento das vivências. O presente estudo possibilitou conhecer as concepções dos moradores da comunidade em relação às práticas e saberes em saúde, e reconhecer o papel do intercâmbio de conhecimento

7.
São Paulo; s.n; 1973. 231 p.
Tesis en Portugués | Index Psicología - Tesis | ID: pte-23773

RESUMEN

Descreve a atividade desenvolvida numa instituição psiquiátrica visando a modificação do comportamento de pacientes crônicos com problemas comportamentais variados. Utiliza instruções e reforçamento positivo no desenvolvimento e manutenção das respostas de higiene matinal. Esse procedimento é eficiente enquanto estas condições se mantem, ocasião em que todos sujeitos apresentam uma alta estabilidade na emissão das respostas. Retiradas as instruções, parte dos sujeitos deixa de emiti-las. Os resultados sugerem que um procedimento de reforçamento positivo e instruções pode ser útil para manter comportamentos semelhantes de pacientes permanentemente institucionados, que estejam sob o controle de economia de fichas. No entanto, é desejável que a modificação do comportamento obtido nessas condições possa se manter quando o sujeito retornar ao seu meio social de origem. Conclui que um sistema de economia de fichas ser um sistema artificial a menos que, antes do sujeito retornar ao seu meio social de origem, faça uso das mesmas contingências existentes naquele meio (AU)

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