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1.
Biopreserv Biobank ; 18(5): 403-408, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32799560

RESUMO

l-Carnitine (LC) plays a key role in sperm metabolism, easily providing energy through ß-oxidation, which positively affects motility. The objective of this study was to investigate the association between blood plasma and seminal plasma LC levels, as well as the effect of LC as an additive in a skimmed milk-based extender during sperm storage at 5°C. In the first experiment, semen and blood samples from 14 Quarter Horse stallions were used. The LC content in blood plasma and seminal plasma was determined by spectrophotometry and their relationships with seminal parameters were evaluated. In the second experiment, ejaculates (n = 16) from four Quarter Horses were used. Each ejaculate was split into four treatment groups with different LC concentrations: 0 (control), 0.5, 1.0, and 2.0 mM. Sperm motility, integrity of plasma and acrosomal membranes, intracellular reactive oxygen species content, and plasma membrane stability were evaluated immediately after samples reached 5°C (0 hour) and after 24, 48, and 72 hours. There was a positive correlation (p < 0.05) between LC levels in seminal plasma with both sperm concentration and plasma and acrosomal membrane integrity. Furthermore, the addition of LC (1 and 2 mM) preserved the motility of equine sperm stored at 5°C. It was concluded that the concentrations of LC with seminal plasma present correlate to semen parameters and the addition of LC to skimmed milk-based extender preserves the motility of equine sperm stored at 5°C for up to 48 hours.


Assuntos
Preservação do Sêmen , Motilidade dos Espermatozoides , Animais , Carnitina , Cavalos , Humanos , Masculino , Sêmen , Análise do Sêmen , Espermatozoides
2.
Analyst ; 144(17): 5232-5244, 2019 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-31360935

RESUMO

Leishmaniasis comprises a group of infectious diseases with worldwide distribution, of which both the visceral and cutaneous forms are caused by Leishmania parasites. In the absence of vaccines, efficacious chemotherapy remains the basis for leishmaniasis control. The available drugs are expensive and associated with several secondary adverse effects. Due to these limitations, the development of new antileishmanial compounds is imperative, and plants offer various perspectives in this regard. The present study evaluated the in vitro leishmanicidal activity of flavonoids isolated from Solanum paludosum Moric. and investigated the mechanisms of cell death induced by them. These compounds were evaluated in vitro for their antileishmanial activity against Leishmania amazonensis promastigotes and they showed prominent leishmanicidal activity. The EtOAc fraction, gossypetin 3,7,8,4'-tetra-O-methyl ether (1), and kaempferol 3,7-di-O-methyl ether (3) were selected to be used in an in vitro assay against L. amazonensis amastigotes and cell death assays. The flavonoids (1) and (3) presented significant activity against L. amazonensis amastigotes, exhibiting the IC50 values of 23.3 ± 4.5 µM, 34.0 ± 9.6 µM, and 10.5 ± 2.5 µM for the EtOAc fraction, (1), and (3), respectively, without toxic effects to the host cells. Moreover, (1) and (3) induced blocked cell cycle progression at the G1/S transition, ultimately leading to G1/G0 arrest. Flavonoid (3) also induced autophagy. Using Raman spectroscopy in conjunction with principal component analysis, the biochemical changes in the cellular components induced by flavonoids (1) and (3) were presented. The obtained results indicated that the mechanisms of action of (1) and (3) occurred through different routes. The results support that the flavonoids derived from S. paludosum can become lead molecules for the design of antileishmanial prototypes.


Assuntos
Antiprotozoários/farmacologia , Morte Celular/efeitos dos fármacos , Flavonoides/farmacologia , Citometria de Fluxo/métodos , Leishmania/efeitos dos fármacos , Animais , Antiprotozoários/química , Autofagia/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Flavonoides/química , Quempferóis/química , Quempferóis/farmacologia , Leishmania/citologia , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Camundongos , Análise Espectral Raman , Estreptófitas/química
3.
Molecules ; 21(1): E11, 2015 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-26703549

RESUMO

The Cactaceae family is composed by 124 genera and about 1438 species. Pilosocereus gounellei, popularly known in Brazil as xique-xique, is used in folk medicine to treat prostate inflammation, gastrointestinal and urinary diseases. The pioneering phytochemical study of P. gounellei was performed using column chromatography and HPLC, resulting in the isolation of 10 substances: pinostrobin (1), ß-sitosterol (2), a mixture of sitosterol 3-O-ß-d-glucopyranoside/stigmasterol 3-O-ß-d-glucopyranoside (3a/3b), 13²-hydroxyphaeophytin a (4), phaeophytin a (5), a mixture of ß-sitosterol and stigmasterol (6a/6b), kaempferol (7), quercetin (8), 7'-ethoxy-trans-feruloyltyramine (mariannein, 9) and trans-feruloyl tyramine (10). Compound 9 is reported for the first time in the literature. The structural characterization of the compounds was performed by analyses of 1-D and 2-D NMR data. In addition, a phenolic and flavonol total content assay was carried out, and the anti-oxidant potential of P. gounellei was demonstrated.


Assuntos
Antioxidantes/química , Cactaceae/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Antioxidantes/farmacologia , Cromatografia Líquida de Alta Pressão , Ácidos Cumáricos/química , Ácidos Cumáricos/farmacologia , Flavonoides/química , Flavonoides/farmacologia , Medicina Tradicional , Estrutura Molecular , Fenóis/química , Fenóis/farmacologia , Tiramina/análogos & derivados , Tiramina/química , Tiramina/farmacologia
4.
Molecules ; 19(4): 5434-47, 2014 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-24879587

RESUMO

This paper presents the quantification, antioxidant and antimicrobial activity of capsaicin, dihydrocapsaicin and the flavonoid chrysoeriol isolated from different extracts (hexane and acetonitrile extracts from whole fruit, peel and seed) of Capsicum frutescens (pimenta malagueta). The acetonitrile extract of the seeds, peel and whole fruits contained capsaicin as a major component, followed in abundance by dihydrocapsaicin and chrysoeriol. The antimicrobial activity of the isolated compounds against seven microorganisms showed chrysoeriol was the most active compound. In the antioxidant test, the acetonitrile extract from the whole fruit showed the highest activity. The antioxidant activity of pimenta malagueta may be correlated with its phenolic content, principally with the most active compound, capsaicin.


Assuntos
Antibacterianos/química , Capsicum/química , Sequestradores de Radicais Livres/química , Fenóis/química , Extratos Vegetais/química , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Benzotiazóis/química , Compostos de Bifenilo/química , Candida albicans/efeitos dos fármacos , Sequestradores de Radicais Livres/farmacologia , Radicais Livres/química , Frutas/química , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Fenóis/farmacologia , Picratos/química , Extratos Vegetais/farmacologia , Ácidos Sulfônicos/química
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