Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 21
Filtrar
1.
J Ethnopharmacol ; 104(1-2): 87-91, 2006 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-16236477

RESUMEN

Sphenocentrum jollyanum crude extracts and an isolated constituent were evaluated for anti-inflammatory activity using the carrageenan-induced hind paw oedema of healthy adult albino rats and utilizing the oral route of administration. The fruit methanol extract (79.58% inhibition at 200 mg kg(-1)) gave a higher anti-inflammatory activity than the root extract (53.75% inhibition at 200 mg ml(-1)). Further purification of the most active fruit methanol extract (MFE) led to the isolation of three furanoditerpenes identified as columbin, isocolumbin, fibleucin (uv, ir, nmr and ms) as well as a flavonoid-rich fraction (FDE). Both columbin (67.08% inhibition at 20 mg kg(-1), p<0.05) and FDE (76.25% inhibition at 200 mg kg(-1); p<0.05) gave significant anti-inflammatory activities in comparable range with reference acetylsalicylic acid (72.5% inhibition at 100 mg kg(-1)). The results provide some justification for the folkloric uses of Sphenocentrum jollyanum in the treatment of inflammatory-based diseases across the West African sub-region.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Diterpenos/uso terapéutico , Menispermaceae , Metanol/uso terapéutico , Animales , Diterpenos/aislamiento & purificación , Relación Dosis-Respuesta a Droga , Edema/inducido químicamente , Edema/tratamiento farmacológico , Frutas , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/uso terapéutico , Raíces de Plantas , Ratas
2.
Phytochemistry ; 47(6): 991-6, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9564731

RESUMEN

From fresh leaves of Alberta magna two new iridoids and a known cyclopentene dialdehyde have been identified. One of the new compounds has the less-common irido-lactone structure and has an enolic hydrogen on C-4. Two of the compounds show short term mosquito-repellent effects.


Asunto(s)
Glucósidos/química , Control Biológico de Vectores , Piranos/química , Árboles , Animales , Culicidae , Glucósidos/aislamiento & purificación , Glucósidos/toxicidad , Iridoides , Hojas de la Planta , Piranos/aislamiento & purificación , Piranos/toxicidad , Sudáfrica
3.
Phytochemistry ; 29(3): 1004-7, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-1366479

RESUMEN

Two new chromone glycosides, schumanniofiosides A and B have been isolated from the root bark of Schumanniophyton magnificum and their structures shown to be 2-methyl-5,7-dihydroxychromone 5-O-beta-D-glucopyranoside and 2-methyl-5,7-dihydroxychromone 7-O-beta-D-glucopyranosyl-(1----2)-apiofuranoside, respectively. The structures were elucidated by a combination of spectral data and chemical degradation.


Asunto(s)
Cromonas/aislamiento & purificación , Glucósidos/aislamiento & purificación , Glicósidos/aislamiento & purificación , Plantas Medicinales , Conformación de Carbohidratos , Secuencia de Carbohidratos , Espectroscopía de Resonancia Magnética , Datos de Secuencia Molecular , Estructura Molecular , Árboles
4.
Phytochemistry ; 37(6): 1667-70, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7766003

RESUMEN

Two new oleanolic acid saponins were isolated from the leaves and roots of Beta vulgaris. Both contained the unusual feature of a 3,4 seco-glycopyranosyl moiety. Their structures were established by a combination of 2D NMR experiments and of Californium plasma desorption mass spectrometry.


Asunto(s)
Glicósidos/aislamiento & purificación , Ácido Oleanólico/química , Verduras/química , Secuencia de Carbohidratos , Glicósidos/química , Espectroscopía de Resonancia Magnética , Datos de Secuencia Molecular
5.
Phytochemistry ; 38(6): 1497-500, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7786481

RESUMEN

A novel derivative of sucrose, beta-(3,6-di-O-feruloyl)-fructofuranosyl-alpha-(2,3,4,6-tetra-O-ac etyl)- glucopyranoside, was isolated from the wood of Bhesa paniculata. Its structure was determined by a combination of 2D 1H-1H and 1H-13C correlation NMR spectroscopy. The known compounds, glycerol 1-9',12'-octadecadienoate, beta-sitosterol, (+/-)-pinoresinol, methyl 3,4-dihydroxybenzoate, 4-hydroxy-3-methoxybenzoic acid, anofinic acid and 2-(1'-methylethenyl)-benzofuran-5-carboxylic acid were also isolated.


Asunto(s)
Ácidos Cumáricos/química , Plantas Medicinales/química , Sacarosa/análogos & derivados , Árboles/química , Conformación de Carbohidratos , Secuencia de Carbohidratos , Cromatografía Líquida de Alta Presión/métodos , Ácidos Cumáricos/análisis , Ácidos Cumáricos/aislamiento & purificación , Indonesia , Espectroscopía de Resonancia Magnética , Malasia , Modelos Estructurales , Datos de Secuencia Molecular , Sacarosa/química , Sacarosa/aislamiento & purificación
6.
Folia Microbiol (Praha) ; 55(5): 422-6, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20941575

RESUMEN

Antimicrobial activity of crude seed extract of Moringa oleifera was investigated by thin layer chromatography bioassay against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Cladosporium cladosporioides, and Penicillium sclerotigenum; most of them were prominently inhibited by an isolate with R(F) 0.92-0.96. Characterization and identification of the extract revealed the occurrence of three bioactive compounds: 4-(α-L-rhamnopyranosyloxy)benzyl isothiocyanate, methyl N-4-(α-L-rhamnopyranosyloxy) benzyl carbamate (both known compounds), and 4-(ß-D-glucopyranosyl-1→4-α-L-rhamnopyranosyloxy)-benzyl thiocarboxamide, existence of which in any Moringa spp. or plant is reported for the first time. The UV spectrum of the novel compound showed maximum absorption at 273 and 225 nm in MeOH while the IR spectrum revealed several characteristic bands at 3100, 2900, 1700, 1500, 1300, 1100 and 1000 cm(-1). The (1)H-NMR showed signals at 1.2 and 3.77 ppm and the (13)C-NMR presented signals at 155, 122, 91.7 and 98.4 ppm. All the compounds at 5 mg/L had very high bactericidal activity against some of test pathogens even at contact period 1-2 h. 4-(ß-D-Glucopyranosyl-1→4-α-L-rhamnopyranosyloxy)benzyl thiocarboxamide was the most potent, with 99.2 % inhibition toward Shigella dysenteriae and 100 % toward Bacillus cereus, E. coli and Salmonella typhi within 4 h of contact.


Asunto(s)
Antiinfecciosos/farmacología , Bacterias/efectos de los fármacos , Glucósidos/farmacología , Moringa oleifera/química , Extractos Vegetales/farmacología , Semillas/química , Bacterias/clasificación , Bioensayo , Cromatografía en Capa Delgada/métodos , Recuento de Colonia Microbiana , Hongos/clasificación , Hongos/efectos de los fármacos , Glucosinolatos/química , Glucosinolatos/farmacología , Isotiocianatos/química , Isotiocianatos/farmacología , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana/métodos , Extractos Vegetales/química
8.
Exp Brain Res ; 125(3): 281-6, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10229019

RESUMEN

Although it is obvious that vision plays a primary role in reaching and grasping objects, the sources of the visual information used in programming and controlling various aspects of these movements is still being investigated. One source of visual information is feedback relating to the characteristics of the reach itself for example, the speed and trajectory of the moving limb and the change in the posture of the hand and fingers. The present study selectively eliminated this source of visual information by blocking the subject's view of the reaching limb with an opaque barrier while still enabling subjects to view the goal object. Thus, a direct comparison was made between standard (closed-loop) and object-only (open-loop) visual-feedback conditions in a situation in which the light levels and contrast between an object and its surroundings were equivalent in both viewing conditions. Reach duration was longer with proportionate increases in both the acceleration and deceleration phases when visual feedback of the reaching limb was prevented. Maximum grip aperture and the proportion of movement time at which it occurred were the same in both conditions. Thus, in contrast to previous studies that did not employ constant light levels across closed- and open-loop reaching conditions, a dissociation was found between the spatial and temporal dimensions of grip formation. It appears that the posture of the hand can be programmed without visual feedback of the hand--presumably via a combination of visual information about the goal object and proprioceptive feedback (and/or efference copy). Nevertheless, maximum grip aperture (like the kinematic markers examined in the transport component) was also delayed when visual feedback of the reaching limb was selectively prevented. In other words, the relative timing of kinematic events was essentially unchanged, reflecting perhaps a tight coupling between the transport and grip components.


Asunto(s)
Retroalimentación/fisiología , Fuerza de la Mano/fisiología , Propiocepción/fisiología , Desempeño Psicomotor/fisiología , Aceleración , Adulto , Análisis de Varianza , Fenómenos Biomecánicos , Desaceleración , Femenino , Mano/fisiología , Humanos , Masculino , Neuronas Motoras/fisiología , Neuronas Aferentes/fisiología , Estimulación Luminosa
9.
Br J Anaesth ; 51(4): 339-45, 1979 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-380608

RESUMEN

The effects of premedication with the anticholinergic drugs atropine, hyoscine and glycopyrronium when administered by oral and i.m. routes have been evaluated in patients undergoing minor surgery and compared with a placebo using a double-dummy double-blind technique. Although the mouths of those patients who received adequate doses of anticholinergic drugs were dry, subjectively and observed, as compared with those who received a placebo, the overall course of anaesthesia did not appear to be different. Of the three drugs atropine seemed to be absorbed best following oral administration. Equally effective oral and i.m. doses of atropine were considered to be 2.0 and 1.0 mg respectively; of hyoscine 1.0 and 0.25--0.5 mg. The appropriate dose of glycopyrronium was 0.2 mg i.m. The routine use of anticholinergic drugs in preanaesthetic medication in minor surgery appears to be unnecessary.


Asunto(s)
Parasimpatolíticos , Medicación Preanestésica , Administración Oral , Adulto , Atropina/administración & dosificación , Atropina/farmacología , Ensayos Clínicos como Asunto , Método Doble Ciego , Estudios de Evaluación como Asunto , Glicopirrolato/administración & dosificación , Glicopirrolato/farmacología , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Inyecciones Intramusculares , Parasimpatolíticos/administración & dosificación , Parasimpatolíticos/farmacología , Salivación/efectos de los fármacos , Escopolamina/administración & dosificación , Escopolamina/farmacología
10.
J Nat Prod ; 49(4): 583-7, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3783156

RESUMEN

The stem bark of Teclea ouabanguiensis has yielded six triterpenoids, two of which are new. The known compounds were identified spectroscopically as 7-deacetylazadirone (2), 7-deacetylproceranone (3), tecleanin, (4), and lupeol. The novel compounds include the tetranortriterpenoids, 7-deacetoxy-7-oxoazadirone (1), and ouabanginone (5). The biogenetic significance of the presence of these limonoids in T. ouabanguienis is discussed.


Asunto(s)
Plantas Medicinales/análisis , Triterpenos/análisis , Camerún , Espectroscopía de Resonancia Magnética , Extractos Vegetales/análisis
11.
J Neurophysiol ; 84(3): 1645-55, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10980034

RESUMEN

An anti-saccade, which is a saccade directed toward a mirror-symmetrical position in the opposite visual field relative to the visual stimulus, involves at least three separate operations: covert orienting, response suppression, and coordinate transformation. The distinction between pro- and anti-saccades can also be applied to pointing. We used fMRI to compare patterns of brain activation during pro- and anti-movements, to determine whether or not additional areas become active during the production of anti-movements. In parietal cortex, an inferior network was active during both saccades and pointing that included three foci along the intraparietal sulcus: 1) a posterior superior parietal area (pSPR), more active during the anti-tasks; 2) a middle inferior parietal area (mIPR), active only during the anti-tasks; and 3) an anterior inferior parietal area (aIPR), equally active for pro- and anti-movement. A superior parietal network was active during pointing but not saccades and included the following: 1) a medial region, active during anti- but not pro-pointing (mSPR); 2) an anterior and medial region, more active during pro-pointing (aSPR); and 3) an anterior and lateral region, equally active for pro- and anti-pointing (lSPR). In frontal cortex, areas selectively active during anti-movement were adjacent and anterior to areas that were active during both the anti- and pro-tasks, i.e., were anterior to the frontal eye field and the supplementary motor area. All saccade areas were also active during pointing. In contrast, foci in the dorsal premotor area, the anterior superior frontal region, and anterior cingulate were active during pointing but not saccades. In summary, pointing with central gaze activates a frontoparietal network that includes the saccade network. The operations required for the production of anti-movements recruited additional frontoparietal areas.


Asunto(s)
Mapeo Encefálico , Lóbulo Frontal/fisiología , Lóbulo Parietal/fisiología , Movimientos Sacádicos/fisiología , Adulto , Electrooculografía , Femenino , Dedos/fisiología , Fijación Ocular/fisiología , Lóbulo Frontal/anatomía & histología , Mano/fisiología , Humanos , Imagen por Resonancia Magnética , Masculino , Red Nerviosa/fisiología , Lóbulo Parietal/anatomía & histología , Estimulación Luminosa , Desempeño Psicomotor/fisiología , Muñeca/fisiología
12.
J Nat Prod ; 46(3): 379-90, 1983.
Artículo en Inglés | MEDLINE | ID: mdl-6619886

RESUMEN

A structure/activity study of selected limonoids from two plant families (Meliaceae and Rutaceae) of the Rutales order against the murine P-388 lymphocytic leukemia system was undertaken. The presence of both a 19 leads to 28 lactol and a 14,15 beta-epoxide group was found especially important for pronounced inhibition of the PS in vitro cell line. Substitution of an A-ring alpha,beta-unsaturated ketone (3-oxo-1-ene) for the lactol led to diminished activity, while reduction of the olefin caused complete loss of activity. At the dose levels employed, even very good PS in vitro inhibition was not translated into PS in vivo antineoplastic effects.


Asunto(s)
Antineoplásicos Fitogénicos , Leucemia P388/tratamiento farmacológico , Leucemia Experimental/tratamiento farmacológico , Terpenos/farmacología , Animales , Ratones , Plantas Medicinales , Relación Estructura-Actividad
14.
Nat Prod Rep ; 18(2): 131-47, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11336285
16.
Nat Prod Rep ; 17(5): 463-82, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11072894
19.
Nat Prod Rep ; 11(1): 91-117, 1994 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15206458
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA