Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Más filtros












Base de datos
Intervalo de año de publicación
1.
Fitoterapia ; 176: 106016, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38740345

RESUMEN

Over the years, the biological activities of seaweeds could have piqued research interest due to their specific functional phytochemistry, which may not be available in terrestrial plants. Seaweeds produce these compounds to overcome and control stressful biotic and abiotic conditions. Additionally, they are potentially excellent sources of highly useful leads in the development of new drugs. Our study aims to unveil, for the first time, an overview of Halopteris scoparia, a species belonging to the Phaeophyceae class and the Stypocaulacea family, by summarizing all available literature data. In this work, we attempt to shed light on its phytochemistry, nutritional values, pharmacological activities, and industrial uses and applications. To gather information related to H. scoparia, relevant keywords were used to search internet databases including Google Scholar, PubMed, ResearchGate, Web of Science, Algae Database, WoRMS database, and DORIS database. The chemical structures were drawn using Chemdraw and verified using the PubChem database. Chemically, this species contains a wide variety of secondary metabolites, such as terpenoids and phenolic compounds. Additionally, other chemical components with nutraceutical value have been identified, such as carbohydrates, proteins, lipids, pigments, minerals and mycosporine like amino acids. Then, holding several reported pharmacological properties, including antioxidant, anti-inflammatory, cytotoxic, dermoprotective, antidepressive, antibacterial, antibiofilm, antifungal, anti-parasitic activities and acute toxicity. In addition to other their applications such as bioconversion and antifouling activities. To confirm the previous pharmacological properties, more comprehensive and systematic in vivo, preclinical, and clinical studies are needed. Furthermore, research is required to uncover the mechanisms of its active compounds and their potential therapeutic effects in treating other diseases such as atherosclerosis, neurodegenerative diseases, and viral infections.


Asunto(s)
Phaeophyceae , Fitoquímicos , Fitoquímicos/farmacología , Fitoquímicos/aislamiento & purificación , Fitoquímicos/química , Phaeophyceae/química , Humanos , Estructura Molecular , Animales , Algas Marinas/química
2.
Chem Biodivers ; 17(7): e2000121, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32374938

RESUMEN

Carpodesmia tamariscifolia is a brown alga rich in (poly)phenols with important cytotoxic and antioxidant effects. However, the relationship between its chemical composition and its effects is unknown. The aim of this study is to identify the potential compounds and mechanisms responsible for its main effects. The alga was extracted consecutively with hexane, dichloromethane and methanol and further fractionated using Sephadex LH-20 and silica gel columns when appropriate. The fractions were subjected to thin-layer chromatography and liquid chromatography-mass spectrometry analysis and evaluated for their total phenolic content (Folin-Ciocalteu assay), radical scavenging activity (DPPH assay), cytotoxic activity (MTT assay on the SH-SY5Y cell line), and ability to generate H2 O2 (Amplex Red assay). Chromatographic and phenolic analyses of the fractions indicate that abundant redox-active phenols are present in all the fractions and that a high amount of prenylated hydroquinone derivatives is present in the apolar ones. In the hexane and dichloromethane fractions, the cytotoxic and antioxidant activities are closely related to their phenolic content, whereas in the methanol fractions, the cytotoxicity is negatively related to the phenolic content and the antioxidant activity is positively related to it. In the same tests, hydroquinone behaves as both strong cytotoxic and antioxidant agent. H2 O2 assay shows that C. tamariscifolia fractions and hydroquinone can autoxidize and generate H2 O2 . Our results suggest that redox-active phenols produce the pharmacological effects described for C. tamariscifolia and that the hydroquinone moiety of prenylated hydroquinone derivatives is responsible for both cytotoxic (through a pro-oxidant mechanism secondary to its autoxidation) and antioxidant effects of the apolar fractions.


Asunto(s)
Antineoplásicos/farmacología , Antioxidantes/farmacología , Fenoles/farmacología , Algas Marinas/química , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Compuestos de Bifenilo/antagonistas & inhibidores , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Estructura Molecular , Oxidación-Reducción , Fenoles/química , Fenoles/aislamiento & purificación , Picratos/antagonistas & inhibidores , Relación Estructura-Actividad , Células Tumorales Cultivadas
3.
Parasitol Res ; 111(2): 571-5, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22402609

RESUMEN

Giardiasis is a gastrointestinal infection of wide distribution that is more prevalent in childhood. Easy and rapid diagnosis of giardiasis is essential for reduction of this infection. This cross-sectional study included 62 children in which collection of saliva, stool and serum samples was performed. An enzyme-linked immunosorbent assay (ELISA) technique was evaluated to detect IgA and IgG responses in both saliva and serum samples. Twenty-two children were positive for Giardia duodenalis infection by direct examination of faecal specimens, 20 non-infected and 20 infected with other parasites. Salivary and serum IgA and IgG responses against G. duodenalis infection were significantly higher in Giardia parasitized than non-Giardia parasitized children (p < 0.001). This concludes that specific salivary IgA may serve as a diagnostic tool and specific salivary IgG as a screening tool in monitoring the exposure of various populations to Giardia duodenalis. The advantage of salivary assays over serum immunoglobulin assay is being easy and non-invasive in sampling technique which is important especially for young children.


Asunto(s)
Giardiasis/inmunología , Inmunoglobulina A Secretora/análisis , Inmunoglobulina A/sangre , Inmunoglobulina G/sangre , Saliva/inmunología , Niño , Preescolar , Estudios Transversales , Egipto/epidemiología , Femenino , Giardiasis/epidemiología , Humanos , Inmunoglobulina G/análisis , Masculino
4.
Parasitol Res ; 106(2): 505-11, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19953268

RESUMEN

Blastocystis sp. has been described as the most common intestinal parasite in humans and has an increased impact in public health. To improve our understanding of the molecular epidemiology of this human-emerging parasite, we determined the Blastocystis subtypes (STs) and their relative frequency in Egyptian patients living in or in the vicinity of Cairo and presenting gastrointestinal symptoms. We obtained a total of 20 stool samples identified as positive for Blastocystis by microscopic examination of smears. Genotyping using partial small subunit ribosomal RNA gene analysis identified a total of 21 Blastocystis isolates corresponding to 19 single infections and one mixed infection (ST1 and ST3). Three STs were identified: ST3 was the most common ST in the present Egyptian population (61.90%) followed by ST1 (19.05%) and ST2 (19.05%). Together with previous studies carried out in different areas in Egypt, a total of five STs (ST1, ST2, ST3, ST4, and ST6) have been found in symptomatic patients. These data were compared to those available in the literature, and we underlined variations observed in the number and relative proportions of STs between and within countries. On the whole, it seemed that Blastocystis infection is likely not associated with specific STs even if some STs are predominant in the epidemiologic studies, but rather with a conjunction of factors in the course of infection including environmental risk and parasite and host factors.


Asunto(s)
Infecciones por Blastocystis/epidemiología , Infecciones por Blastocystis/parasitología , Blastocystis/clasificación , Blastocystis/genética , Adolescente , Adulto , Blastocystis/aislamiento & purificación , Niño , Análisis por Conglomerados , ADN Protozoario/química , ADN Protozoario/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Egipto/epidemiología , Heces/parasitología , Femenino , Gastroenteritis/epidemiología , Gastroenteritis/parasitología , Genes de ARNr , Humanos , Masculino , Persona de Mediana Edad , Epidemiología Molecular , Datos de Secuencia Molecular , Filogenia , ARN Protozoario/genética , ARN Ribosómico 18S/genética , Análisis de Secuencia de ADN , Adulto Joven
5.
Exp Parasitol ; 101(1): 77-81, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-12243742

RESUMEN

Recent studies have suggested that intracellular Wolbachia bacteria are necessary for reproduction and survival of adult filarial worms. We now report results of in vitro studies of effects of antibacterial antibiotics (tetracycline, rifampicin, chloramphenicol, azithromycin, and doxycycline) on Brugia malayi infective larvae (L3) motility and molting. All of the antibiotics tested except chloramphenicol decreased L3 motility by 50% or more at 10 days, with minimal effective concentrations (MECs) of 20-100 microg/ml. Tetracyclines, rifampicin, and chloramphenicol inhibited L3 to L4 molting by 12 days in a concentration- and time-dependent manner, with MECs in the range of 1-20 microg/ml. These studies show that antibiotics active against Rickettsiaceae inhibit B. malayi L3 molting at low concentrations in vitro; higher concentrations kill the larvae. While it is possible that antibiotics directly affect filarial L3, we believe it is more likely that the effects seen are indirect effects related to bacterial killing.


Asunto(s)
Antibacterianos/farmacología , Brugia Malayi/efectos de los fármacos , Animales , Azitromicina/farmacología , Brugia Malayi/crecimiento & desarrollo , Brugia Malayi/microbiología , Brugia Malayi/fisiología , Cloranfenicol/farmacología , Relación Dosis-Respuesta a Droga , Doxiciclina/farmacología , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Larva/fisiología , Muda/efectos de los fármacos , Movimiento/efectos de los fármacos , Rifampin/farmacología , Tetraciclina/farmacología , Factores de Tiempo , Wolbachia/efectos de los fármacos , Wolbachia/aislamiento & purificación
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...