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1.
J Control Release ; 316: 250-262, 2019 12 28.
Artículo en Inglés | MEDLINE | ID: mdl-31678655

RESUMEN

Pulmonary delivery is increasingly seen as an attractive, non-invasive route for the delivery of forthcoming protein therapeutics. In this context, here we describe protein complexes with a new 'complexing excipient' - vitamin B12-targeted poly(ethylene glycol)-block-poly(glutamic acid) copolymers. These form complexes in sub-200nm size with a model protein, suitable for cellular targeting and intracellular delivery. Initially we confirmed expression of vitamin B12-internalization receptor (CD320) by Calu-3 cells of the in vitro lung epithelial model used, and demonstrated enhanced B12 receptor-mediated cellular internalization of B12-targeted complexes, relative to non-targeted counterparts or protein alone. To develop an inhalation formulation, the protein complexes were spray dried adopting a standard protocol into powders with aerodynamic diameter within the suitable range for lower airway deposition. The cellular internalization of targeted complexes from dry powders applied directly to Calu-3 model was found to be 2-3 fold higher compared to non-targeted complexes. The copolymer complexes show no complement activation, and in vivo lung tolerance studies demonstrated that repeated administration of formulated dry powders over a 3 week period in healthy BALB/c mice induced no significant toxicity or indications of lung inflammation, as assessed by cell population count and quantification of IL-1ß, IL-6, and TNF-α pro-inflammatory markers. Importantly, the in vivo data appear to suggest that B12-targeted polymer complexes administered as dry powder enhance lung retention of their protein payload, relative to protein alone and non-targeted counterparts. Taken together, our data illustrate the potential developability of novel B12-targeted poly(ethylene glycol)-poly(glutamic acid) copolymers as excipients suitable to be formulated into a dry powder product for the inhalation delivery of proteins, with no significant lung toxicity, and with enhanced protein retention at their in vivo target tissue.


Asunto(s)
Sistemas de Liberación de Medicamentos , Excipientes/química , Pulmón/metabolismo , Proteínas/administración & dosificación , Administración por Inhalación , Animales , Línea Celular , Femenino , Humanos , Inflamación/tratamiento farmacológico , Inflamación/patología , Pulmón/patología , Ratones , Ratones Endogámicos BALB C , Tamaño de la Partícula , Polietilenglicoles/química , Ácido Poliglutámico/química , Polvos , Proteínas/farmacocinética , Vitamina B 12/metabolismo
2.
Braz J Med Biol Res ; 47(1): 50-9, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24519091

RESUMEN

Cardiovascular disease is one of the leading causes of death worldwide, and evidence indicates a correlation between the inflammatory process and cardiac dysfunction. Selective inhibitors of cyclooxygenase-2 (COX-2) enzyme are not recommended for long-term use because of potentially severe side effects to the heart. Considering this and the frequent prescribing of commercial celecoxib, the present study analyzed cellular and molecular effects of 1 and 10 µM celecoxib in a cell culture model. After a 24-h incubation, celecoxib reduced cell viability in a dose-dependent manner as also demonstrated in MTT assays. Furthermore, reverse transcription-polymerase chain reaction analysis showed that the drug modulated the expression level of genes related to death pathways, and Western blot analyses demonstrated a modulatory effect of the drug on COX-2 protein levels in cardiac cells. In addition, the results demonstrated a downregulation of prostaglandin E2 production by the cardiac cells incubated with celecoxib, in a dose-specific manner. These results are consistent with the decrease in cell viability and the presence of necrotic processes shown by Fourier transform infrared analysis, suggesting a direct correlation of prostanoids in cellular homeostasis and survival.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Inhibidores de la Ciclooxigenasa 2/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Mioblastos Cardíacos/efectos de los fármacos , Pirazoles/farmacología , Sulfonamidas/farmacología , Animales , Western Blotting , Celecoxib , Línea Celular , Proliferación Celular/genética , Supervivencia Celular/genética , Relación Dosis-Respuesta a Droga , Regulación de la Expresión Génica/genética , ARN Mensajero/efectos de los fármacos , ARN Mensajero/genética , Ratas , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Espectroscopía Infrarroja Corta , Factores de Tiempo
3.
Braz. j. med. biol. res ; 47(1): 50-59, 01/2014. tab, graf
Artículo en Inglés | LILACS | ID: lil-697673

RESUMEN

Cardiovascular disease is one of the leading causes of death worldwide, and evidence indicates a correlation between the inflammatory process and cardiac dysfunction. Selective inhibitors of cyclooxygenase-2 (COX-2) enzyme are not recommended for long-term use because of potentially severe side effects to the heart. Considering this and the frequent prescribing of commercial celecoxib, the present study analyzed cellular and molecular effects of 1 and 10 µM celecoxib in a cell culture model. After a 24-h incubation, celecoxib reduced cell viability in a dose-dependent manner as also demonstrated in MTT assays. Furthermore, reverse transcription-polymerase chain reaction analysis showed that the drug modulated the expression level of genes related to death pathways, and Western blot analyses demonstrated a modulatory effect of the drug on COX-2 protein levels in cardiac cells. In addition, the results demonstrated a downregulation of prostaglandin E2 production by the cardiac cells incubated with celecoxib, in a dose-specific manner. These results are consistent with the decrease in cell viability and the presence of necrotic processes shown by Fourier transform infrared analysis, suggesting a direct correlation of prostanoids in cellular homeostasis and survival.


Asunto(s)
Animales , Ratas , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , /farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Mioblastos Cardíacos/efectos de los fármacos , Pirazoles/farmacología , Sulfonamidas/farmacología , Western Blotting , Línea Celular , Proliferación Celular/genética , Supervivencia Celular/genética , Relación Dosis-Respuesta a Droga , Regulación de la Expresión Génica/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , ARN Mensajero/efectos de los fármacos , ARN Mensajero/genética , Espectroscopía Infrarroja Corta , Factores de Tiempo
4.
Biotechniques ; 26(6): 1134-8, 1140-2, 1144 passim, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10376153

RESUMEN

Human tumor samples were screened for point mutations by adapting a mobility-shift assay to automated DNA sizing. This screen identifies the type of point mutation and relative amount of mutated DNA sequences present in a sample. Test samples having known hypoxanthine-guanine phosphoribosyl transferase (hprt)/exon-3 sequence mutations were characterized by: (i) PCR amplification, (ii) fluorescent dye-primer extension with 36-atom linker derived deoxycytosine or deoxyuridine triphosphate and the remaining three natural nucleotides and (iii) sizing of the resulting fluorescently labeled modified strands, using an automated DNA sequencer. Routinely, a range of sizes is observed among the sequence variants of a single DNA target sequence. This is because nucleotide analogs are incorporated into DNA strands in a sequence-dependent manner, resulting in composition-dependent electrophoretic mobility. Thus, point mutations are identified as shifts in mobility between the fluorescently labeled modified strands of the control and test samples. The twenty different hprt/exon-3 single-base substitution mutations tested were easily identified, even at fourfold dilution with control DNA.


Asunto(s)
Análisis Mutacional de ADN/métodos , ADN de Neoplasias/genética , Pruebas Genéticas/métodos , Mutación Puntual , Animales , Secuencia de Bases , Biopsia , Células CHO , Color , Cricetinae , Cartilla de ADN , ADN de Neoplasias/análisis , Exones , Colorantes Fluorescentes , Genes ras/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Datos de Secuencia Molecular , Polimorfismo Conformacional Retorcido-Simple , Neoplasias Gástricas/genética , Neoplasias Gástricas/patología
6.
Artículo en Portugués | LILACS | ID: lil-3059

RESUMEN

Por meio do cotrimoxazol, foram tratados 30 individuos, representados por criancas e adultos, com pediculose da cabeca. A conduta usada correspondeu a administracao de um comprimido com 400 mg de sulfametoxazol e 80 mg de trimetoprim cada 12 horas, durante tres dias, com repeticao de igual serie medicamentosa depois de intervalo com dez dias de duracao. Ocorreram 28 (93,3%) curas, demonstrando a eficacia do novo metodo curativo referente a infestacao pelo Pediculus humanus humanus. Essas verificacoes, alem de consubstanciarem opcao sob o ponto de vista terapeutico, criam a necessidade de esclarecer o mecanismo de acao do medicamento em apreco em face a processo motivado por inseto e, tambem, estabelecem a conveniencia de procurar saber se identica atividade sucede no que concerne a outras ectoparasitoses


Asunto(s)
Antiinfecciosos Urinarios , Infestaciones por Piojos
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