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1.
Braz J Biol ; 78(1): 98-107, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28658390

RESUMO

The family Verbenaceae hosts important species used in traditional medicine of many countries. The taxonomic controversies concerning the specific delimitation of several of its species make it difficult to guarantee the botanical origin of herbal preparations based on species of this family. To contribute to the development of both specific chemomarkers and a quality control tool to authenticate the botanical origin of herbal preparations of Verbenacea species, we determined the foliar HPLC-DAD phenolic profiles and the antioxidant properties of 10 wild species of this family occurring in Mexico. The contents of phenols and flavonoids varied significantly among species. Priva mexicana showed the highest levels of total phenolics (53.4 mg g-1 dry tissue) and Verbena carolina had the highest levels of flavonoids (17.89 mg g-1 dry tissue). Relevant antioxidant properties revealed by antiradical and reducing power were found for the analyzed species. These properties varied significantly in a species-dependent manner. The phenolic compounds accumulated were flavones and phenolic acids. Flavones were the only type of flavonoids found. The results of a cluster analysis showed that the compounds were accumulated in species-specific profiles. The phenolic profiles are proposed as valuable chemomarkers that can become a useful tool for the quality control concerning the botanical origin of herbal medicinal preparations based on the species analyzed. In addition, phenolic profiles could contribute importantly to solve the taxonomic controversies concerning species delimitation in the family Verbenaceae.


Assuntos
Antioxidantes , Fenóis , Extratos Vegetais , Verbenaceae , Antioxidantes/análise , Antioxidantes/química , Biomarcadores/análise , Biomarcadores/química , Cromatografia Líquida de Alta Pressão , Flavonoides/análise , Flavonoides/química , México , Fenóis/análise , Fenóis/química , Extratos Vegetais/análise , Extratos Vegetais/química
2.
Physiol Behav ; 47(1): 107-12, 1990 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2326325

RESUMO

In order to examine sex differences in non sexual behavior, 40 rats of each sex from two strains (gray, A x C and albino, Sprague-Dawley) were trained, using different experimental procedures. In Experiment I, aversive conditioning in a one-way (easy task) and a two-way (difficult task) active avoidance task was examined. Results consistently showed that males of both strains were inferior to females in the acquisition of the two-way avoidance task. A significant interaction between sex of both strains and the difficulty of the task was found. In Experiment II, rats were trained in a Sutherland Apparatus in an easy (black vs. white) and a difficult (horizontal vs. vertical) visual discrimination task, using appetitive reinforcement; no differences between sexes were observed. A significant interaction, however, was found between strain and task, indicating a lower performance of the A x C strain in the difficult task. The results are discussed within the theoretical framework of the Yerkes-Dodson Law, which states a relationship between drive level, performance and different degrees of task difficulty.


Assuntos
Comportamento Apetitivo/fisiologia , Aprendizagem da Esquiva/fisiologia , Aprendizagem por Discriminação/fisiologia , Caracteres Sexuais , Estimulação Acústica , Animais , Eletrochoque , Feminino , Masculino , Ratos , Ratos Endogâmicos , Especificidade da Espécie
3.
J Exp Anal Behav ; 38(2): 117-23, 1982 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16812290

RESUMO

In Experiment 1, six naive pigeons were trained on a foraging schedule characterized by different states beginning with a search state in which completion of a fixed-interval on a white key led to a choice state. In the choice state the subject could, by appropriate responding on a fixed ratio of three, either accept or reject the schedule of reinforcement that was offered (either a variable-interval five-second or a variable-interval 20-second). If the subject accepted the schedule, it entered a "handling state" in which the appropriate variable-interval schedule was presented. Completion of the variable-interval schedule produced food. The independent variable was the fixed-interval value in the search state, and the dependent variable was the rate of acceptance of the long variable-interval in the choice state. Experiment 2 was identical except that the search state required completion of a variable-interval, instead of a fixed-interval, schedule. The rate of acceptance of the long variable-interval schedule in both experiments was a direct function of the length of the search state, in accordance with both optimality theory and the delay-reduction hypothesis.

4.
Braz. j. biol ; 78(1): 98-107, Feb. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-888842

RESUMO

Abstract The family Verbenaceae hosts important species used in traditional medicine of many countries. The taxonomic controversies concerning the specific delimitation of several of its species make it difficult to guarantee the botanical origin of herbal preparations based on species of this family. To contribute to the development of both specific chemomarkers and a quality control tool to authenticate the botanical origin of herbal preparations of Verbenacea species, we determined the foliar HPLC-DAD phenolic profiles and the antioxidant properties of 10 wild species of this family occurring in Mexico. The contents of phenols and flavonoids varied significantly among species. Priva mexicana showed the highest levels of total phenolics (53.4 mg g-1 dry tissue) and Verbena carolina had the highest levels of flavonoids (17.89 mg g-1 dry tissue). Relevant antioxidant properties revealed by antiradical and reducing power were found for the analyzed species. These properties varied significantly in a species-dependent manner. The phenolic compounds accumulated were flavones and phenolic acids. Flavones were the only type of flavonoids found. The results of a cluster analysis showed that the compounds were accumulated in species-specific profiles. The phenolic profiles are proposed as valuable chemomarkers that can become a useful tool for the quality control concerning the botanical origin of herbal medicinal preparations based on the species analyzed. In addition, phenolic profiles could contribute importantly to solve the taxonomic controversies concerning species delimitation in the family Verbenaceae.


Resumo A família Verbenaceae compreende importantes espécies utilizadas na medicina popular de muitos países. As dificuldades taxonômicas relativas à delimitação específica de muitas das suas espécies face difícil a verificar a origem botânico das preparações herbales baseadas nas espécies desta família. Para fazer uma contribuição ao desenvolvimento de indicadores taxonômicos e dum método de controle de qualidade para verificar a origem botânico de preparações herbales das espécies de Verbenaceae, os perfis fenólicos, obtidos pares HPLC-DAD, e as atividades antioxidantes das folhas de 10 espécies selvagens Mexicanas desta família foram determinados. Os conteúdos dos compostos fenólicos totais e dos flavonoides foram significativamente diferentes entre as espécies. Priva mexicana apresentou a maior quantidade de compostos fenólicos totais (53.4 mg g-1 amostra seca) e Verbena carolina apresentou a maior quantidade de flavonoides (17.89 mg g-1 amostra seca). Verifica-se importantes propriedades antioxidantes, como os resultados dos ensaios da capacidade antiradical e do poder redutor indicaram. As propriedades antioxidantes foram significativamente diferentes entre as espécies. Verificou-se que os compostos fenólicos conteúdos nas folhas das espécies analisadas foram só flavonas e ácidos fenólicos. Os resultados das análises de agrupamento provarãn que os perfiles fenólicos foram espécie-específicos. Estes perfis podem ser considerados como indicadores químicos da qualidade relativa à origem botânico de preparações medicinais baseadas nas espécies analisadas e podem fazer importantes contribuições para a delimitação específica na família Verbenaceae.


Assuntos
Fenóis/análise , Fenóis/química , Extratos Vegetais/análise , Extratos Vegetais/química , Antioxidantes/análise , Antioxidantes/química , Flavonoides/análise , Flavonoides/química , Biomarcadores/análise , Biomarcadores/química , Cromatografia Líquida de Alta Pressão , Verbenaceae , México
5.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467045

RESUMO

Abstract The family Verbenaceae hosts important species used in traditional medicine of many countries. The taxonomic controversies concerning the specific delimitation of several of its species make it difficult to guarantee the botanical origin of herbal preparations based on species of this family. To contribute to the development of both specific chemomarkers and a quality control tool to authenticate the botanical origin of herbal preparations of Verbenacea species, we determined the foliar HPLC-DAD phenolic profiles and the antioxidant properties of 10 wild species of this family occurring in Mexico. The contents of phenols and flavonoids varied significantly among species. Priva mexicana showed the highest levels of total phenolics (53.4 mg g-1 dry tissue) and Verbena carolina had the highest levels of flavonoids (17.89 mg g-1 dry tissue). Relevant antioxidant properties revealed by antiradical and reducing power were found for the analyzed species. These properties varied significantly in a species-dependent manner. The phenolic compounds accumulated were flavones and phenolic acids. Flavones were the only type of flavonoids found. The results of a cluster analysis showed that the compounds were accumulated in species-specific profiles. The phenolic profiles are proposed as valuable chemomarkers that can become a useful tool for the quality control concerning the botanical origin of herbal medicinal preparations based on the species analyzed. In addition, phenolic profiles could contribute importantly to solve the taxonomic controversies concerning species delimitation in the family Verbenaceae.


Resumo A família Verbenaceae compreende importantes espécies utilizadas na medicina popular de muitos países. As dificuldades taxonômicas relativas à delimitação específica de muitas das suas espécies face difícil a verificar a origem botânico das preparações herbales baseadas nas espécies desta família. Para fazer uma contribuição ao desenvolvimento de indicadores taxonômicos e dum método de controle de qualidade para verificar a origem botânico de preparações herbales das espécies de Verbenaceae, os perfis fenólicos, obtidos pares HPLC-DAD, e as atividades antioxidantes das folhas de 10 espécies selvagens Mexicanas desta família foram determinados. Os conteúdos dos compostos fenólicos totais e dos flavonoides foram significativamente diferentes entre as espécies. Priva mexicana apresentou a maior quantidade de compostos fenólicos totais (53.4 mg g-1 amostra seca) e Verbena carolina apresentou a maior quantidade de flavonoides (17.89 mg g-1 amostra seca). Verifica-se importantes propriedades antioxidantes, como os resultados dos ensaios da capacidade antiradical e do poder redutor indicaram. As propriedades antioxidantes foram significativamente diferentes entre as espécies. Verificou-se que os compostos fenólicos conteúdos nas folhas das espécies analisadas foram só flavonas e ácidos fenólicos. Os resultados das análises de agrupamento provarãn que os perfiles fenólicos foram espécie-específicos. Estes perfis podem ser considerados como indicadores químicos da qualidade relativa à origem botânico de preparações medicinais baseadas nas espécies analisadas e podem fazer importantes contribuições para a delimitação específica na família Verbenaceae.

6.
Anal Bioanal Chem ; 389(6): 1909-17, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17899027

RESUMO

In this work, a new, easy and rapid method of analyzing phenolic compounds in pollen extract, based on capillary electrophoresis coupled with electrospray ionization time-of-flight-mass spectrometry (CE-ESI-TOF-MS), has been developed. A systematic investigation of separation parameters has been performed with respect to resolution, sensitivity, analysis time and peak shape. The electrophoretic parameters and electrospray conditions must be optimized to obtain reproducible analyses. Using this method, several important phenolic compounds such as acetin-glucoside, 7-O-methylherbacetin-3-sophoroside, galloyl-glucose, quercetin-3-sophoroside, apigenin-6,8-di-C-glycoside, quercetin-3-rutinoside, genistein-7-O-beta-D: -glucoside, luteolin-7-O-glucoside, apigenin-7-O-glucoside and 2',4',6'-trihydroxy-3'-formyldihydrochalcone have been determined directly from pollen extract. The efficiency, the rapidity, the small amounts of sample required, and the high resolution of CE coupled with the sensitivity, the selectivity, the accurate masses and the true isotopic patterns obtained using TOF-MS point to the potential of this approach for identifying the phenolic compounds present in pollen.


Assuntos
Fenóis/análise , Extratos Vegetais/química , Pólen/química , Eletroforese Capilar/métodos , Concentração de Íons de Hidrogênio , Fenóis/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Massas por Ionização por Electrospray/métodos , Temperatura , Fatores de Tempo
7.
Lancet ; 358(9291): 1429-30, 2001 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-11705494

RESUMO

We studied the genotype distribution of cervical human papillomavirus (HPV) infections in an age-stratified sample of 262 women in Mozambique using the PGMYO9-PGMY11 primer system in a reverse line-blot strip-based assay with high sensitivity in type-specific amplification. Despite the low precision of the estimates, we found that HPV-16 was not the dominant type. Instead, HPV 35 was the most commonly identified genotype among HPV-positive women (16/96 [17%]) and women with cervical neoplasia (7/23 [30%]). Certain genotypes might have been under-detected in previous studies, and type-specific HPV distributions might vary across populations. Therefore, the estimated proportion of cervical neoplasia that could be prevented by an HPV-16-based vaccine could be lower than expected.


Assuntos
Papillomaviridae/genética , Infecções por Papillomavirus/epidemiologia , Infecções Tumorais por Vírus/epidemiologia , Displasia do Colo do Útero/virologia , Adolescente , Adulto , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Moçambique/epidemiologia , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/genética , Prevalência , População Rural , Infecções Tumorais por Vírus/genética , Displasia do Colo do Útero/epidemiologia , Displasia do Colo do Útero/genética
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