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1.
Infect Disord Drug Targets ; 19(1): 73-80, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-29366429

RESUMEN

BACKGROUND: In recent years, very few effective drugs against Mycobacterium tuberculosis have emerged, which motivates the research with drugs already used in the treatment of tuberculosis. Ethambutol is a bacteriostatic drug that affects cell wall integrity, but the effects of this drug on bacilli are not fully exploited. OBJECTIVE: Based on the need to better investigate the complex mechanism of action of ethambutol, our study presented the proteome profile of M. tuberculosis after different times of ethambutol exposure, aiming to comprehend the dynamics of bacilli response to its effects. M. tuberculosis was exposed to ½ MIC of ethambutol at 24 and 48 hours. The proteins were identified by MALDI-TOF/TOF. RESULTS: The main protein changes occurred in metabolic proteins as dihydrolipoyl dehydrogenase (Rv0462), glutamine synthetase1 (Rv2220), electron transfer flavoprotein subunit beta (Rv3029c) and adenosylhomocysteinase (Rv3248c). CONCLUSION: Considering the functions of these proteins, our results support that the intermediary metabolism and respiration were affected by ethambutol and this disturbance provided proteins that could be explored as additional targets for this drug.


Asunto(s)
Antituberculosos/farmacología , Proteínas Bacterianas/metabolismo , Etambutol/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , Tuberculosis/tratamiento farmacológico , Antituberculosos/uso terapéutico , Pared Celular/efectos de los fármacos , Etambutol/uso terapéutico , Humanos , Redes y Vías Metabólicas/efectos de los fármacos , Pruebas de Sensibilidad Microbiana/métodos , Mycobacterium tuberculosis/metabolismo , Proteoma/efectos de los fármacos , Proteoma/aislamiento & purificación , Factores de Tiempo , Tuberculosis/microbiología
2.
Curr Microbiol ; 74(12): 1453-1460, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28840299

RESUMEN

Tetradenia riparia (Lamiaceae) is native to Central Africa popularly known as myrrh, used in folk medicine to treat various diseases like malaria, gastroenteritis, and tropical skin disease. This research was to evaluate the antioxidant and antibacterial activities of the crude extract (CE) and fractions (FR) of the T. riparia by classical chromatography. The CE of T. riparia leaves was submitted to column chromatographic fractionation to obtain four fractions of the interest, which were identified by nuclear magnetic resonance and gas chromatograph coupled to mass spectrum: FR-I (abieta-7,9(11)-dien-13-ß-ol), FR-II (Ibozol), FR-III (8 (14), 15-sandaracopimaradiene-2α, 18-diol and 8 (14), 15-sandaracopimaradiene-7α, 18-diol), and FR-IV (Astragalin, Boronolide and Luteolin). Total phenol content of CE and FR were measured, and antioxidant action by methods of DPPH (2,2-diphenyl-1-picrylhydrazyl), ß-carotene/linoleic acid system, and ferric reducing/antioxidant power (FRAP) and the antibacterial activity was evaluated by the broth microdilution method with the determination of the minimum inhibitory concentration (MIC). The FR-IV presented antioxidant potential with 181.67 µg gallic acid/mg, IC50 of 0.61 µg/mL by DPPH method, 55.61% oxidation protection by ß-carotene/linoleic acid system and 4.59 µM ferrous sulfate/mg of sample by FRAP, and the FR-I showed higher antibacterial potential on the strain Staphylococcus aureus with MIC 0.98 µg/mL, Enterococcus faecalis and Bacillus cereus with MIC 31.2 µg/mL. Thus, the fractionation of CE was extremely important to detect fractions with potential activities, and investigations are necessary regarding the mechanism of action and action in vivo.


Asunto(s)
Antibacterianos/farmacología , Antioxidantes/farmacología , Lamiaceae/química , Extractos Vegetales/farmacología , África Central , Antibacterianos/aislamiento & purificación , Antioxidantes/aislamiento & purificación , Bacillus cereus/efectos de los fármacos , Brasil , Cromatografía Liquida , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Concentración 50 Inhibidora , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta/química
3.
Curr Pharm Biotechnol ; 17(6): 532-9, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26778457

RESUMEN

The conventional techniques used to extract natural products have many disadvantages, and alternative methods have been used, such as supercritical fluid extraction (SFE-CO2). We compared the anti-Mycobacterium tuberculosis activity and cytotoxicity of extracts and major pure compounds were obtained from the leaves of Calophyllum brasiliense by SFE-CO2, maceration and Soxhlet. Anti-M tuberculosis activity was evaluated by resazurin microtiter assay plate and cytotoxicity assay was performed using 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide. The (-) mammea A/BB, (-) mammea B/BB, mammea B/BB cyclo D, ponnalide, mammea A/BA cyclo D, and amentoflavone were identified as the majority compounds. SFE-CO2, especially at 313 K and 10.92 MPa showed better yield for (-) mammea A/BB. Anti-M. tuberculosis activity (62.5 µg/mL) and cytotoxicity (Selectivity Index = 0.320-0.576) were similar for the three extracts. Mammea B/BB cyclo D had a minimum inhibitory concentration (MIC) of 125 µg/mL, and ponnalide and mammea A/BA cyclo D had MICs > 250 µg/mL. The pure compounds isolated showed low Selectivity Index (< 0.09). SFE-CO2 may be more promising than conventional methods for the extraction of compound (-) mammea A/BB, which presented the best anti-M. tuberculosis activity in our previous study. This is important for current industrial requirements to obtain extracts from medicinal plants using clean technologies.


Asunto(s)
Antituberculosos/farmacología , Calophyllum , Mycobacterium tuberculosis/efectos de los fármacos , Extractos Vegetales/farmacología , Antituberculosos/química , Biflavonoides/análisis , Biflavonoides/farmacología , Cromatografía con Fluido Supercrítico , Cumarinas/análisis , Cumarinas/farmacología , Pruebas de Sensibilidad Microbiana , Mycobacterium tuberculosis/crecimiento & desarrollo , Extractos Vegetales/química , Hojas de la Planta
4.
J Clin Lab Anal ; 24(6): 403-6, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21089171

RESUMEN

We aimed to compare Hitchens-Pike-Todd-Hewitt (HPTH) enrichment broth, Todd-Hewitt broth, and direct culture onto blood sheep agar containing selective antimicrobial (ABA) in screening Group B Streptococci (GBS) carriage in pregnant women. From April to June 2007, duplicate lower vaginal and duplicate anorectal specimens of 102 pregnant women at 35 weeks of gestation or more, who were assisted at Santa Casa de Misericórdia Hospital, Maringá, Paraná, Brazil, were screened by GBS using HPTH, Todd-Hewitt broth, and ABA. Twenty-five (24.5%) pregnant women had one or more positive culture for GBS in those media. The positive rate for each medium was 21.6% (22/102) in the HPTH, 12.8% (13/102) in ABA, and 11.8% (12/102) in Todd-Hewitt broth. HPTH seems to be a high satisfactory medium for screening GBS in vaginal and anorectal samples in pregnant women and additional studies would be interesting in a larger number of pregnant women and in different laboratories.


Asunto(s)
Portador Sano/diagnóstico , Medios de Cultivo , Complicaciones Infecciosas del Embarazo/diagnóstico , Infecciones Estreptocócicas/diagnóstico , Streptococcus/aislamiento & purificación , Canal Anal/microbiología , Brasil/epidemiología , Portador Sano/epidemiología , Portador Sano/microbiología , Femenino , Humanos , Tamizaje Masivo/métodos , Embarazo , Complicaciones Infecciosas del Embarazo/epidemiología , Complicaciones Infecciosas del Embarazo/microbiología , Tercer Trimestre del Embarazo , Prevalencia , Recto/microbiología , Infecciones Estreptocócicas/epidemiología , Infecciones Estreptocócicas/microbiología , Streptococcus/crecimiento & desarrollo , Vagina/microbiología
5.
Rev. saúde pública ; 30(3): 273-9, jun. 1996. tab
Artículo en Portugués | LILACS | ID: lil-174437

RESUMEN

Realizou-se inquérito sorológico e epidemiológico para cisticercose em indivíduos de cinco municípios da regiäo Norte do Estado do Paraná, Brasil. De 2.180 indivíduos investigados através da reaçäo de imunofluorescência indireta, 69 (3,2 por cento) apresentaram títulos significativos de anticorpos anti-Cysticercus cellulosae. Os percentuais de indivíduos com títulos significativos encontrados em Sarandi (6,6 por cento) e Marialva (4,7 por cento) näo diferem estatisticamente (Z=1.319, P=0,0936), mas diferem dos percentuais encontrados em Mandaguaçu, Paiçandu e Maringá (P<0,01). Destes indivíduos, 47,9 por cento estavam na faixa etária de 21 a 49 anos e 79,4 por cento eram do sexo feminino. Foi comum o relato de queixas como "dores de cabeça" (70,6 por cento), "tonturas" (57,4 por cento) e "convulsöes" (7,4 por cento), além de história de teníase (22,1 por cento) e hábitos de ingestäo de carne crua bovina (41,2 por cento) ou suína 27,9 por cento) e carne com "canjiquinha' (25,0 por cento)


Asunto(s)
Humanos , Masculino , Femenino , Cisticercosis/inmunología , Cisticercosis/epidemiología , Anticuerpos Antihelmínticos/aislamiento & purificación , Cisticercosis/diagnóstico , Anticuerpos Antihelmínticos , Cerebro/parasitología , Heces/análisis , Técnica del Anticuerpo Fluorescente
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