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1.
Braz. j. microbiol ; 45(4): 1349-1355, Oct.-Dec. 2014. tab
Artículo en Inglés | LILACS | ID: lil-741286

RESUMEN

In the last times, focus on plant research has increased all over the world. Euphorbia tirucalli L., a plant known popularly as Aveloz, and originally used in Africa, has been drawing attention for its use in the United States and Latin America, both for use as an ornamental plant and as a medicinal plant. E. tirucalli L. is a member of the family Euphorbiaceae and contains many diterpenoids and triterpenoids, in particular phorbol esters, apparently the main constituent of this plant, which are assumed to be responsible for their activities in vivo and in vitro. The in vitro antifungal activities of Euphorbia tirucalli (L.) against opportunistic yeasts were studied using microbroth dilution assay. The results showed that aqueous extract and latex preparation were effective against ten clinical strains of Cryptococcus neoformans in vitro (Latex and extract MIC range of 3.2 - > 411 µg/mL). Aiming the safe use in humans, the genotoxic effects of E. tirucalli were evaluated in human leukocytes cells. Our data show that both aqueous extract and latex preparation have no genotoxic effect in human leukocytes cells in vitro. Although the results cannot be extrapolated by itself for use in vivo, they suggest a good perspective for a therapeutic application in future. In conclusion, our results show that the aqueous extract and latex preparation from E. tirucalli L. are antifungal agents effectives against several strains of C. neoformans and do not provoke DNA damage in human leukocyte cells, considering the concentrations tested.


Asunto(s)
Humanos , Antifúngicos/farmacología , Cryptococcus neoformans/efectos de los fármacos , Euphorbiaceae/química , Leucocitos/efectos de los fármacos , Mutágenos/toxicidad , Extractos Vegetales/farmacología , Antifúngicos/aislamiento & purificación , Antifúngicos/toxicidad , Pruebas de Sensibilidad Microbiana , Pruebas de Mutagenicidad , Mutágenos/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/toxicidad
2.
Hist. ciênc. saúde-Manguinhos ; 21(4): 1093-1112, Oct-Dec/2014.
Artículo en Portugués | LILACS | ID: lil-732505

RESUMEN

O objetivo deste trabalho é analisar o discurso do excesso sexual produzido pelo pensamento social brasileiro das décadas de 1920 e 1930 na sua interlocução com o discurso médico da época. De inspiração foucaultiana, o texto inscreve-se no campo da história dos saberes e está subsidiado por documentos sociológicos e médicos do período de referência. No quadro da recodificação vintecentista sobre o imaginário da brasilidade, o tema do excesso sexual foi revisitado pelo pensamento sociológico local, forjando-o ora como um perturbador do projeto civilizatório nacional, ora como um traço que deveria ser positivado por ter sido a condição de possibilidade da hibridização cultural de suas matrizes identitárias.


The objective of this article is to analyze the discourse of sexual excess produced by Brazilian social thinking in the 1920s and 1930s and its dialog with the medical discourse at the time. Inspired by Foucault, it is within the field of the history of knowledge and is supported by sociology and medical documents from the period in question.Within the framework of the twentieth century re-codification of the imagery of Brazilianness, the topic of sexual excess was revisited by local thinkers in the field of sociology and seen either as disturbing the national civilizing project, or as a trait that should be seen in a positive light because it permitted the cultural hybridization of its sources of identity.


Asunto(s)
Animales , Bovinos , Adenina/metabolismo , Aductos de ADN/metabolismo , Compuestos Epoxi/metabolismo , Guanina/metabolismo , Mutágenos/metabolismo , Aductos de ADN/química , Aductos de ADN/aislamiento & purificación , Compuestos Epoxi/química , Compuestos Epoxi/aislamiento & purificación , Guanosina/metabolismo , Mutágenos/química , Mutágenos/aislamiento & purificación
4.
Braz. j. microbiol ; 43(1): 78-88, Jan.-Mar. 2012. ilus, tab
Artículo en Inglés | LILACS | ID: lil-622792

RESUMEN

The purpose of the current study was intended to obtain the enhanced production of bacitracin by Bacillus licheniformis through random mutagenesis and optimization of various parameters. Several isolates of Bacillus licheniformis were isolated from local habitat and isolate designated as GP-35 produced maximum bacitracin production (14±0.72 IU ml-1). Bacitracin production of Bacillus licheniformis GP-35 was increased to 23±0.69 IU ml-1 after treatment with ultraviolet (UV) radiations. Similarly, treatment of vegetative cells of GP-35 with chemicals like N-methyl N'-nitro N-nitroso guanidine (MNNG) and Nitrous acid (HNO2) increased the bacitracin production to a level of 31±1.35 IU ml-1 and 27±0.89 IU ml-1 respectively. Treatment of isolate GP-35 with combined effect of UV and chemical treatment yield significantly higher titers of bacitracin with maximum bacitracin production of 41.6±0.92 IU ml-1. Production of bacitracin was further enhanced (59.1±1.35 IU ml-1) by optimization of different parameters like phosphate sources, organic acids as well as temperature and pH. An increase of 4.22 fold in the production of bacitracin after mutagenesis and optimization of various parameters was achieved in comparison to wild type. Mutant strain was highly stable and produced consistent yield of bacitracin even after 15 generations. On the basis of kinetic variables, notably Yp/s (IU/g substrate), Yp/x (IU/g cells), Yx/s (g/g), Yp/s, mutant strain B. licheniformis UV-MN-HN-6 was found to be a hyperproducer of bacitracin.


Asunto(s)
Bacillus/aislamiento & purificación , Bacitracina/aislamiento & purificación , Compuestos Químicos/análisis , Mutagénesis , Mutágenos/análisis , Mutágenos/aislamiento & purificación , Cinética , Métodos , Optimización de Procesos , Estándares de Referencia , Radiación
5.
Braz. j. med. biol. res ; 42(9): 816-823, Sept. 2009. tab
Artículo en Inglés | LILACS | ID: lil-524313

RESUMEN

Pueraria mirifica is a Thai phytoestrogen-rich herb traditionally used for the treatment of menopausal symptoms. Pueraria lobata is also a phytoestrogen-rich herb traditionally used in Japan, Korea and China for the treatment of hypertension and alcoholism. We evaluated the mutagenic and antimutagenic activity of the two plant extracts using the Ames test preincubation method plus or minus the rat liver mixture S9 for metabolic activation using Salmonella typhimurium strains TA98 and TA100 as indicator strains. The cytotoxicity of the two extracts to the two S. typhimurium indicators was evaluated before the mutagenic and antimutagenic tests. Both extracts at a final concentration of 2.5, 5, 10, or 20 mg/plate exhibited only mild cytotoxic effects. The plant extracts at the concentrations of 2.5, 5 and 10 mg/plate in the presence and absence of the S9 mixture were negative in the mutagenic Ames test. In contrast, both extracts were positive in the antimutagenic Ames test towards either one or both of the tested mutagens 2-(2-furyl)-3-(5-nitro-2-furyl)-acrylamide and benzo(a)pyrene. The absence of mutagenic and the presence of anti-mutagenic activities of the two plant extracts were confirmed in rec-assays and further supported by a micronucleus test where both plant extracts at doses up to 300 mg/kg body weight (equivalent to 16 g/kg body weight plant tuberous powder) failed to exhibit significant micronucleus formation in rats. The tests confirmed the non-mutagenic but reasonably antimutagenic activities of the two plant extracts, supporting their current use as safe dietary supplements and cosmetics.


Asunto(s)
Animales , Masculino , Ratas , Antimutagênicos/farmacología , Bacillus subtilis/efectos de los fármacos , Hígado/efectos de los fármacos , Mutágenos/toxicidad , Extractos Vegetales/farmacología , Pueraria/química , Salmonella typhimurium/efectos de los fármacos , Antimutagênicos/aislamiento & purificación , Antimutagênicos/toxicidad , Bacillus subtilis/genética , Pruebas de Micronúcleos/métodos , Mutágenos/aislamiento & purificación , Extractos Vegetales/toxicidad , Ratas Sprague-Dawley , Espectrofotometría , Salmonella typhimurium/genética , Factores de Tiempo
6.
Indian J Exp Biol ; 2001 Oct; 39(10): 1068-70
Artículo en Inglés | IMSEAR | ID: sea-57959

RESUMEN

Pretreatment of aqueous extracts of Zyrulina (Spirulina), Aswagandha (Withania) and Nopane (Boswellia) on colchicine induced chromosome damage showed weakness of clastogenic activity in Swiss albino mice. None of the treatments increased significantly the number of chromosome aberrations.


Asunto(s)
Eucariontes/química , Animales , Proteínas Bacterianas/química , Boswellia/química , Aberraciones Cromosómicas/efectos de los fármacos , Suplementos Dietéticos/toxicidad , Ratones , Mutagénesis/efectos de los fármacos , Pruebas de Mutagenicidad , Mutágenos/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Plantas Medicinales/toxicidad , Spirulina
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