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1.
J Control Release ; 316: 250-262, 2019 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-31678655

RESUMO

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.


Assuntos
Sistemas de Liberação de Medicamentos , Excipientes/química , Pulmão/metabolismo , Proteínas/administração & dosagem , Administração por Inalação , Animais , Linhagem Celular , Feminino , Humanos , Inflamação/tratamento farmacológico , Inflamação/patologia , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C , Tamanho da Partícula , Polietilenoglicóis/química , Ácido Poliglutâmico/química , Pós , Proteínas/farmacocinética , Vitamina B 12/metabolismo
2.
Braz J Med Biol Res ; 47(1): 50-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24519091

RESUMO

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.


Assuntos
Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Inibidores de Ciclo-Oxigenase 2/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Mioblastos Cardíacos/efeitos dos fármacos , Pirazóis/farmacologia , Sulfonamidas/farmacologia , Animais , Western Blotting , Celecoxib , Linhagem Celular , Proliferação de Células/genética , Sobrevivência Celular/genética , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica/genética , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/genética , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Espectroscopia de Luz Próxima ao Infravermelho , Fatores de Tempo
3.
Braz. j. med. biol. res ; 47(1): 50-59, 01/2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-697673

RESUMO

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.


Assuntos
Animais , Ratos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , /farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Mioblastos Cardíacos/efeitos dos fármacos , Pirazóis/farmacologia , Sulfonamidas/farmacologia , Western Blotting , Linhagem Celular , Proliferação de Células/genética , Sobrevivência Celular/genética , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/genética , Espectroscopia de Luz Próxima ao Infravermelho , Fatores de Tempo
4.
Biotechniques ; 26(6): 1134-8, 1140-2, 1144 passim, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10376153

RESUMO

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.


Assuntos
Análise Mutacional de DNA/métodos , DNA de Neoplasias/genética , Testes Genéticos/métodos , Mutação Puntual , Animais , Sequência de Bases , Biópsia , Células CHO , Cor , Cricetinae , Primers do DNA , DNA de Neoplasias/análise , Éxons , Corantes Fluorescentes , Genes ras/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Dados de Sequência Molecular , Polimorfismo Conformacional de Fita Simples , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia
6.
Artigo em Português | LILACS | ID: lil-3059

RESUMO

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


Assuntos
Anti-Infecciosos Urinários , Infestações por Piolhos
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