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2.
Int J Tuberc Lung Dis ; 23(10): 1082-1089, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31627773

RESUMO

SETTING: TBM-KIDS is a phase I/II trial enrolling children with tuberculous meningitis (TBM) in three tertiary referral centers in India and Malawi.OBJECTIVE: To describe the challenges encountered in conducting the first randomized clinical trial of antimicrobial agents in pediatric TBM.DESIGN: The sources of the data were primarily monthly trial reports, non-enrollment case report forms, study diaries and registers maintained for recruitment, experiences shared by key team members during regular study calls and comments from site review visits. We reviewed, broadly categorized, and describe in detail the challenges encountered by study teams in trial implementation.RESULTS: Over 17 months, 3371 children with clinical presentations consistent with meningoencephalitis or undergoing lumbar puncture were assessed for eligibility; 21 (<1%) met enrollment criteria. We encountered challenges related to diagnosis, management of sick children, large catchment areas, adverse event attribution, concomitant medications, infrastructure requirements, expensive pediatric formulations with short expiry, and detection of treatment response in a highly variable disease across the age continuum. Training and adaptation of tools for neurocognitive and neurologic function assessment were necessary. Special care was undertaken to explain study participation to distraught caregivers and manage children longitudinally.CONCLUSION: Interventional trials in pediatric TBM are challenging but are critically important for improving the treatment of a disease that disables children physically, cognitively and emotionally. Sharing these challenges may help to address them more effectively as a TB research community and to advance treatments for this at-risk population.


Assuntos
Antituberculosos/administração & dosagem , Cuidadores/psicologia , Projetos de Pesquisa , Tuberculose Meníngea/tratamento farmacológico , Criança , Pré-Escolar , Seguimentos , Humanos , Índia , Lactente , Malaui , Tuberculose Meníngea/diagnóstico
3.
Chem Biol Interact ; 167(1): 19-30, 2007 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-17328876

RESUMO

The present study is on the growth inhibitory effect of Withania somnifera methanolic leaf extract and its active component, withanolide on HL-60 promyelocytic leukemia cells. The decrease in survival rate of HL-60 cells was noted to be associated with a time dependent decrease in the Bcl-2/Bax ratio, leading to up regulation of Bax. Both the crude leaf extract and the active component activated the apoptotic cascade through the cytochrome c release from mitochondria. The activation of caspase 9, caspase 8 and caspase 3 revealed that caspase was a key mediator in the apoptotic pathway. DNA fragmentation analysis revealed typical ladders as early as 12h indicative of caspase 3 role in the apoptotic pathway. Flow cytometry data demonstrated an increase of sub-G1 peak upon treatment by 51% at 24h, suggesting the induction of apoptotic cell death in HL-60 cells.


Assuntos
Apoptose , Ergosterol/análogos & derivados , Withania/química , Caspase 3/metabolismo , Proliferação de Células/efeitos dos fármacos , Citocromos c/metabolismo , Fragmentação do DNA , Ergosterol/farmacologia , Células HL-60 , Humanos , Metanol/química , Mitocôndrias/metabolismo , Extratos Vegetais/farmacologia , Folhas de Planta/química , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Rodamina 123/metabolismo , Proteína X Associada a bcl-2/biossíntese
4.
Acta Virol ; 48(3): 159-66, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15595209

RESUMO

Complete nucleotide sequences except the poly (C) tract and poly (A) tail of a vaccine strain (IND 491/97) and an atypical field isolate (IND 321/01) of Foot-and-mouth disease virus (FMDV) serotype Asia1 are described. Amino acid (aa) sequence analysis of the VP1 protein of the field isolate revealed that the latter has 212 instead of 210 or 211 aa found in the so far available sequences of other FMDV isolates of Asia1 serotype. The insertion was localized in the hypervariable region of aa 130-160 of VP1 protein. Nucleotide sequencing of the entire genome was therefore carried out to detect changes in other parts of the genome, if any, besides VP1, which could contribute to its fitness. An 8.16 kb sequence of IND 491/97 and an 8.162 kb sequence of IND 321/01 were compared with each other and also with the known sequence of IND 63/72, another vaccine strain of serotype Asia1. Comparison of the entire polyprotein coding (L to 3D) region of IND 321/01 with those of the two Asia1 vaccine strains (IND 63/72 and IND 491/97) revealed no significant differences. A similar comparison of IND 491/97 with IND 63/72 revealed variability across the entire length of the genome. In addition to the capsid-coding region, sequence variability was also observed in non-structural proteins albeit to different extent. This study shows that in the gene pool of serotype Asia1 at least three groups of isolates/strains are present with respect to the length of VP1 protein.


Assuntos
Proteínas do Capsídeo/genética , Vírus da Febre Aftosa/genética , Vacinas Virais/genética , Sequência de Aminoácidos , Sequência de Bases , Vírus da Febre Aftosa/imunologia , Vírus da Febre Aftosa/isolamento & purificação , Variação Genética , Genoma Viral , Dados de Sequência Molecular , Alinhamento de Sequência , Homologia de Sequência do Ácido Nucleico , Sorotipagem , Proteínas não Estruturais Virais/genética
5.
Br J Cancer ; 87(1): 98-105, 2002 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-12085264

RESUMO

Conventional solvent fractionation and bioactivity based target assays were used to identify a new anti-cancer molecule from Phyllanthus urinaria, a herbal medicinal plant used in South India. At each step of the purification process the different fractions that were isolated were tested for specific anti-proliferative activity by assays measuring the inhibition of [(3)H]thymidine incorporation, and trypan blue drug exclusion. The ethyl acetate fraction that contained the bioactivity was further purified and resolved by HPLC on a preparative column. The purity of each of the fractions and their bioactivity were checked. Fraction 3 demonstrated a single spot on TLC and showed maximum anti-proliferative activity. This fraction was further purified and the structure was defined as 7'-hydroxy-3',4',5,9,9'-pentamethoxy-3,4-methylene dioxy lignan using NMR and mass spectrometry analysis. The pure compound and the crude ethyl acetate fraction which showed anti-proliferative activities were examined for ability to target specific markers of apoptosis like bcl2, c-myc and caspases and for effects on telomerase. Four specific cancer cell lines HEp2, EL-1 monocytes, HeLa and MCP7 were used in this study. The results indicate that 7'-hydroxy-3',4',5,9,9'-pentamethoxy-3,4-methylene dioxy lignan was capable of inhibiting telomerase activity and also could inhibit bcl2 and activate caspase 3 and caspase 8 whose significance in the induction of apoptosis is well known. We believe that this compound could serve as a valuable chemotherapeutic drug after further evaluations.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose , Caspases/farmacologia , Divisão Celular/efeitos dos fármacos , Euphorbiaceae/química , Lignanas/farmacologia , Extratos Vegetais/farmacologia , Preparações de Plantas , Telomerase/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Ensaios de Seleção de Medicamentos Antitumorais , Indução Enzimática , Genes myc , Humanos , Lignanas/isolamento & purificação , Estruturas Vegetais , Solventes , Telomerase/antagonistas & inibidores , Células Tumorais Cultivadas
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