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1.
Braz J Med Biol Res ; 48(2): 111-9, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25517919

RESUMEN

Pancreatic cancer is the fourth leading cause of cancer death. Gemcitabine is widely used as a chemotherapeutic agent for the treatment of pancreatic cancer, but the prognosis is still poor. Berberine, an isoquinoline alkaloid extracted from a variety of natural herbs, possesses a variety of pharmacological properties including anticancer effects. In this study, we investigated the anticancer effects of berberine and compared its use with that of gemcitabine in the pancreatic cancer cell lines PANC-1 and MIA-PaCa2. Berberine inhibited cell growth in a dose-dependent manner by inducing cell cycle arrest and apoptosis. After berberine treatment, the G1 phase of PANC-1 cells increased by 10% compared to control cells, and the G1 phase of MIA-PaCa2 cells was increased by 2%. Whereas gemcitabine exerts antiproliferation effects through S-phase arrest, our results showed that berberine inhibited proliferation by inducing G1-phase arrest. Berberine-induced apoptosis of PANC-1 and MIA-PaCa2 cells increased by 7 and 2% compared to control cells, respectively. Notably, berberine had a greater apoptotic effect in PANC-1 cells than gemcitabine. Upon treatment of PANC-1 and MIA-PaCa2 with berberine at a half-maximal inhibitory concentration (IC50), apoptosis was induced by a mechanism that involved the production of reactive oxygen species (ROS) rather than caspase 3/7 activation. Our findings showed that berberine had anti-cancer effects and may be an effective drug for pancreatic cancer chemotherapy.


Asunto(s)
Antineoplásicos Fitogénicos/uso terapéutico , Apoptosis/efectos de los fármacos , Berberina/uso terapéutico , Fase G1/efectos de los fármacos , Neoplasias Pancreáticas/tratamiento farmacológico , Especies Reactivas de Oxígeno/metabolismo , Antimetabolitos Antineoplásicos/uso terapéutico , Caspasa 3/efectos de los fármacos , Caspasa 7/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapéutico , Citometría de Flujo , Humanos , Factores de Tiempo , Gemcitabina
2.
J Sports Med Phys Fitness ; 45(2): 178-82, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16355078

RESUMEN

AIM: This study was designed to study the effects of Panax ginseng extract (PGE) on lipid peroxidation and scavenger enzymes induced by an acute exhaustive exercise in sedentary humans. METHODS: Seven healthy male subjects performed 2 exhaustive incremental exercises on the treadmill before and after 8 weeks' PGE ingestion (2 g each time, 3 times a day) as the control and PGE exercise, respectively. VO2, HR, and exercise duration during exercise were measured. Blood samples were collected at rest, and immediately, 10 and 30 min after each test and used to measure malondialdehyde (MDA), catalase (CAT), and superoxide dismutase (SOD). RESULTS: PGE administration significantly increased exercise duration until exhaustion by 1.5 min (p<0.05). MDA was significantly elevated following both trials (p<0.01), however, it was attenuated after PGE administration (p<0.01). CAT and SOD activities following exercise were significantly elevated, but the activities following control exercise were much lower than those following PGE exercise. CONCLUSIONS: These results suggest that the elevation in CAT and SOD activities as scavenger enzymes after PGE administration result in decrease of MDA level as one of PGE action mechanisms and consequently, prolong exercise duration until exhaustion. These findings support scientific claims that ginseng has ergogenic properties in facilitating recovery from exhaustive exercise.


Asunto(s)
Ejercicio Físico/fisiología , Estrés Oxidativo/efectos de los fármacos , Panax , Extractos Vegetales/farmacología , Adolescente , Adulto , Catalasa/sangre , Prueba de Esfuerzo , Humanos , Masculino , Malondialdehído/sangre , Superóxido Dismutasa/sangre
3.
Biomacromolecules ; 6(4): 2182-8, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16004461

RESUMEN

Highly substituted potato starch phosphate (HPSP) particles were synthesized via an esterification process of potato starch with a mixture of several different concentrations of disodium hydrogen phosphate and sodium hydrogen phosphate. These particles were characterized via thermogravimetric analysis, scanning electron microscope, and inductively coupled plasma mass spectrometer. The electrorheological (ER) fluid was prepared by dispersing these HPSP particles in nonconducting silicone oil, and their ER properties were investigated. The HPSP particle-based ER fluid exhibited typical ER responses with a nonzero yield stress under an applied electric field. We examined the yield stresses for the potato starch-based anhydrous ER system by varying the degree of phosphate substitution and found that the higher polarization induced by the external electric field strength resulted in the higher values of yield stresses and shear stresses.


Asunto(s)
Solanum tuberosum/química , Almidón/química , Conformación de Carbohidratos , Secuencia de Carbohidratos , Microscopía Electrónica de Rastreo , Datos de Secuencia Molecular , Fosforilación , Reología
4.
Biochem Pharmacol ; 60(5): 677-85, 2000 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-10927026

RESUMEN

Ginseng saponins exert various important pharmacological effects with regard to the control of many diseases including cancer. The novel intestinal bacterial metabolites of ginseng protopanaxadiol saponins have recently been found and isolated after the oral administration of ginseng extract in human and rats. 20-O-(beta-D-Glucopyranosyl)-20(S)-protopanaxadiol (IH-901) formed from ginsenosides Rb1, Rb2, and Rc is of particular interest in cancer chemoprevention and treatment. We investigated the effects of IH-901 on the human myeloid leukemia cell line HL-60 in terms of inhibition of proliferation and induction of apoptosis. IH-901 showed a significant cytotoxic activity in HL-60 cells (IC(50) = 24. 3 microM) following a 96-hr incubation. Treatment of HL-60 cells with IH-901 resulted in the formation of internucleosomal DNA fragments. The dose- and time-dependent induction of apoptosis by IH-901 was demonstrated in sandwich enzyme immunoassay and the results were confirmed by flow cytometric analysis. Morphological examination of IH-901-treated samples showed cells with chromatin condensation, cell shrinkage, and nuclear fragmentation, all typical characteristics of apoptotic cells. The treatment of HL-60 cells with IH-901 caused activation of caspase-3 protease and subsequent proteolytic cleavage of poly(ADP-ribose) polymerase. IH-901 did not affect the expression of antiapoptotic protein Bcl-2 but did cause a release of mitochondrial cytochrome c into cytosol. In conclusion, our results demonstrate that IH-901 dramatically suppresses HL-60 cell growth by inducing programed cell death through activation of caspase-3 protease, which occurs via mitochondrial cytochrome c release independently of Bcl-2 modulation. These results may provide a pivotal mechanism for the use of IH-901 in the prevention and treatment of leukemia.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Apoptosis , Caspasas/metabolismo , Ginsenósidos , Mucosa Intestinal/metabolismo , Saponinas/farmacología , Triterpenos/farmacología , Western Blotting , Caspasa 3 , División Celular/efectos de los fármacos , Grupo Citocromo c/metabolismo , Activación Enzimática/efectos de los fármacos , Células HL-60 , Humanos , Mitocondrias/efectos de los fármacos , Mitocondrias/enzimología , Panax/química , Plantas Medicinales , Saponinas/metabolismo
5.
Arch Pharm Res ; 22(6): 633-7, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10615872

RESUMEN

Activity-guided fractionation of the whole plant of Solidago virga-aurea var. gigantea M(IQ). (Compositae) has led to the isolation of three cytotoxic compounds, erythrodiol-3-acetate (1), alpha-tocopherol-quinone (2), and trans-phytol (3) from the hexane soluble fraction. It is the first report of those compounds from the genus.


Asunto(s)
Antineoplásicos/farmacología , Asteraceae/química , Extractos Vegetales/farmacología , Células Tumorales Cultivadas/efectos de los fármacos , Humanos , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/aislamiento & purificación , Ácido Oleanólico/farmacología , Fitol/aislamiento & purificación , Fitol/farmacología , Vitamina E/aislamiento & purificación , Vitamina E/farmacología
6.
Planta Med ; 64(6): 500-3, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9741293

RESUMEN

Ginseng saponin metabolites produced by human intestinal bacteria were evaluated for antigenotoxic properties by testing their effects on benzo[a]pyrene (B[a]P)-induced mutagenicity and clastogenicity. They include 20-O-(beta-D-glucopyranosyl)-20(S)-protopanaxadiol (IH-901), 20-O-(alpha-D-arabinopyranosyl(1-->6)-beta-D-glucopyranosyl]- 20(S)-protopanaxadiol (IH-902) and 20-O-[alpha-D-arabinofuranosyl(1-->6)-beta-D-glucopyranosyl]-20(S)- protopanaxadiol (IH-903). IH-901, IH-902 and IH-903 inhibited the mutagenicity of B[a]P in a dose-dependent manner. In the chromosome aberration assay, IH-901 and IH-903 reduced the frequency of chromosome aberration induced by B[a]P. These results suggest that the ginseng saponin metabolites tested in the present study have potential as chemopreventive agents.


Asunto(s)
Antimutagênicos/química , Antimutagênicos/farmacología , Benzo(a)pireno/toxicidad , Aberraciones Cromosómicas , Intestinos/microbiología , Microsomas Hepáticos/metabolismo , Panax , Plantas Medicinales , Salmonella typhimurium/genética , Saponinas/metabolismo , Saponinas/farmacología , Animales , Benzo(a)pireno/antagonistas & inhibidores , Línea Celular , Cricetinae , Cricetulus , Humanos , Pulmón , Masculino , Pruebas de Mutagenicidad , Ratas , Ratas Sprague-Dawley , Salmonella typhimurium/efectos de los fármacos , Intercambio de Cromátides Hermanas
7.
Planta Med ; 63(5): 436-40, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9342949

RESUMEN

The potential of intestinal bacteria to hydrolyze ginsenoside Rb1 to 20-O-beta-D-glucopyranosyl-20(S)-protopanaxadiol (I) was found in 79% of the fecal specimens from 58 human subjects whose age ranged from 1 to 64 years. Following a ginsenoside-Rb1-hydrolyzing activity assay, Prevotella oris strains were then isolated as a major bacterial species possessing the potential. All the intestinal isolates converted ginsenosides Rb1 and Rd to I, ginsenoside Rb2 to 20-O-[alpha-L-arabinopyranosyl(1-->6)-beta-D-glucopyranosyl]-20(S) -protopanaxadiol (II), and ginsenoside Rc to 20-O-[alpha-L-arabinofuranosyl(1-->6)-beta-D-glucopyranosyl]-20(S)- protopanaxadiol (III) like fecal microflora, but did not attack ginsenosides Re or Rg1 (protopanaxatriol-type). The isolates were susceptible to colimycin (MIC, 3.13 micrograms/ml) and then the treatment of specific pathogen free mice with colimycin (20 mg/kg/day) decreased intestinal bacterial Rb1-hydrolyzing potential from 22.1 +/- 1.2% to 4.7 +/- 2.7%, while the decreased potential was restored to 30.7 +/- 3.7% by the inoculation with P. oris isolates. These results suggest that the metabolism of protopanaxadiol saponins to metabolites I-III in the intestines seems most partly due to intestinal P.oris. In addition, the fact that neither intact ginsenoside Rb1 nor its middle metabolic derivatives but only the final metabolite I was detected at 1.0-7.3 micrograms/ml in blood after oral administration of mice with ginsenoside Rb1 (125 mg/kg) allows us to speculate that metabolites I-III are the most likely forms of protopanaxadiol saponins absorbed from the intestines.


Asunto(s)
Panax , Plantas Medicinales , Prevotella/metabolismo , Saponinas/metabolismo , Adolescente , Adulto , Animales , Niño , Preescolar , Heces/microbiología , Humanos , Hidrólisis , Lactante , Mucosa Intestinal/microbiología , Ratones , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Prevotella/crecimiento & desarrollo , Prevotella/aislamiento & purificación
8.
Planta Med ; 62(5): 453-7, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8923812

RESUMEN

Ginseng saponin metabolites produced by human intestinal bacteria and the urinary and blood compounds after oral administration of Ginseng extract and its saponins in human and specific pathogen-free rats were examined in order to elucidate their metabolites absorbed from the intestines. The main metabolites of ginsenosides Rb1, Rb2, Rc, Re, and Rg1 after anaerobic incubation with fecal flora were identified as 20-O-beta-D-glucopyranosyl-20(S)-protopanaxadiol (I) 20-O-[alpha-L-arabinopyranosyl (1-->6)-beta-D-glucopyranosyl]-20(S)-protopanaxadiol (II), 20-O-[alpha-L- arabinofuranosyl(1-->6)-beta-D-glucopyranosyl]-20(S)-protopanaxadiol+ ++ (III), and 20(S)-protopanaxatriol (IV), though the metabolic rate and mode were affected by fermentation media. Furthermore, metabolites I-IV and 20(S)-protopanaxadiol (XII) were detected in blood (0.3-5.1 micrograms/ml) and in urine (2.2-96 micrograms/ day) after the oral administration of Ginseng extract (150 mg/ kg/day) to human and of total saponin (1 g/kg/day) to rats.


Asunto(s)
Bacterias/metabolismo , Intestinos/microbiología , Panax , Plantas Medicinales , Saponinas/metabolismo , Animales , Heces/microbiología , Ginsenósidos , Humanos , Masculino , Ratas
9.
Planta Med ; 61(5): 409-13, 1995 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7480200

RESUMEN

Examined in vitro were the effects of some triterpenoids from Panax (Araliaceae) and Glycyrrhiza (Leguminosae) spp. on the sensitivity to daunomycin (DAU) and vinblastine (VBL) of adriamycin (ADM)-resistant P388 leukemia cells (P388/ADM), which were resistant to multiple anticancer drugs. Quasipanaxatriol, 20(S)-protopanaxatriol, ginsenoside Rh2, and compound K greatly enhanced the cytotoxicity of the anti-cancer drugs in P388/ADM cells. The extent of enhancement was different among the triterpene compounds; the 4- to 46-fold increase in DAU cytotoxicity was observed in P388/ADM cells in the presence of non-toxic or marginally toxic concentrations of individual compounds, while those for VBL were in the ratios of 2- to 37-fold. The maximum increase in cytotoxicity was observed with 50 microM quasipanaxatriol; the resistance indices defined to be the ratios of the IC50 values for P388/ADM and P388 parental cells decreased from 79 to 1.7 and from 180 to 4.9 in the cases of DAU and VBL, respectively. The reversal of DAU resistance in P388/ADM by quasipanaxatriol could be explained by the effective accumulation of the drugs mediated by the DAU-efflux blockage.


Asunto(s)
Daunorrubicina/farmacología , Leucemia P388/patología , Triterpenos/farmacología , Vinblastina/farmacología , Animales , Transporte Biológico , Daunorrubicina/metabolismo , Daunorrubicina/uso terapéutico , Resistencia a Antineoplásicos , Sinergismo Farmacológico , Fabaceae/química , Femenino , Leucemia P388/tratamiento farmacológico , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos DBA , Panax/química , Plantas Medicinales , Células Tumorales Cultivadas , Vinblastina/uso terapéutico
10.
Radiat Res ; 122(1): 66-71, 1990 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2320726

RESUMEN

The blood flow in RIF-1 tumors of C3H mice, as measured with the 86Rb uptake method, declined markedly after a single heating at 43.5 degrees C or 44.5 degrees C for 1 h. However, preheating at 42.5 degrees C for 1 h significantly lessened the decrease in tumor blood flow caused by subsequent heating at 43.5 degrees C or 44.5 degrees C for 1 h. Such an influence of preheating on the effect of reheating in decreasing the tumor blood flow was significant as early as 6 h after the preheating, peaked at 36 h, and then decayed the following 2-3 days. In fact, a reheating at 43.5 degrees C for 1 h applied 36 h after a preheating at 42.5 degrees C for 1 h resulted in an increase rather than a decrease in blood flow. The cause of such a profound impact of preheating on the effect of reheating on the blood flow is unclear. However, circumstantial evidence including the histopathological appearance of tumors suggests that thermotolerance is induced in the blood vessels of the tumor as a result of preheating.


Asunto(s)
Velocidad del Flujo Sanguíneo , Hipertermia Inducida , Animales , Línea Celular , Miembro Posterior , Ratones , Ratones Endogámicos C3H , Trasplante de Neoplasias , Neoplasias/irrigación sanguínea , Reología , Radioisótopos de Rubidio , Temperatura , Factores de Tiempo
11.
Neurology ; 40(2): 251-6, 1990 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2300243

RESUMEN

From a series of 460 dementia patients referred to a regional brain bank, 14 (3%) patients had a pathologic diagnosis of primary degeneration of the brain involving multiple sites (frontoparietal cortex, striatum, medial thalamus, substantia nigra, and hypoglossal nucleus), with cell loss and astrocytosis. There were no neuronal inclusions and essentially no senile plaques. This entity, which we have termed "dementia lacking distinctive histology" (DLDH), presented with memory loss and personality changes, and led to death, usually within 2 to 7 years. Dysarthria and dysphagia were prominent in the later phases of the illness in most patients. The psychometric findings of some of the patients were consistent with a "frontal" lobe dementia. A few patients had prominent caudate atrophy on CT as well as neuropathologically. Eight of our patients had positive family histories for neurologic disease, mainly dementia. DLDH, in addition to Pick's disease, is a major member of the frontal-lobe dementia group. In patients under age 70 years, the frontal lobe dementias represent an important diagnostic consideration.


Asunto(s)
Encéfalo/patología , Demencia/patología , Anciano , Tronco Encefálico/patología , Demencia/diagnóstico por imagen , Demencia/fisiopatología , Femenino , Humanos , Sistema Límbico/patología , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Telencéfalo/patología , Tálamo/patología , Tomografía Computarizada por Rayos X
12.
Arch Neurol ; 38(4): 243-6, 1981 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7213148

RESUMEN

In two patients the diagnosis of central pontine myelinolysis (CPM), suspected on clinical grounds, was supported by computerized tomographic (CT) sections made perpendicular to the pons, and confirmed on postmortem examination. Extrapontine myelinolysis was suggested on CT scans in both cases, and confirmed in one. Computerized tomography may prove to be a sensitive and accurate diagnostic test for CPM, and may aid in the detection of associated extrapontine lesions.


Asunto(s)
Enfermedades Desmielinizantes/diagnóstico por imagen , Puente/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adulto , Humanos , Masculino , Persona de Mediana Edad , Tálamo/diagnóstico por imagen
13.
J Neuropathol Exp Neurol ; 39(5): 584-97, 1980 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7218000

RESUMEN

In 63 patients with malabsorption syndromes, 16 with congenital biliary atresia (BA) and 47 with cystic fibrosis (CF), axonal dystrophy in the gracile nucleus (ADG) was studied. Of the 16 patients with BA, ADG of considerable severity was observed in all 10 over one year of age. Of the 47 patients with CF, it was observed in 32, 61 and 80% of the cases in the first, second, and third decades, respectively. Evidence is presented that there has been a substantial decrease in the incidence of ADG in CF patients in recent years and that the decreased incidence is attributable to vitamin E (Aquasol E) therapy. The beneficial effect of vitamin E supplementation in CF patients is proffered as strong evidence that ADG in BA and CF is related to vitamin E deficiency. The present study indicates that BA and CF patients require vitamin E supplementation to maintain a normal integrity of axons related to the gracile and perhaps other sensory nuclei. Critical neurological evaluation for possible dysfunction of the sensory nuclei in these patients with malabsorption syndromes is advised.


Asunto(s)
Conductos Biliares/anomalías , Fibrosis Quística/patología , Bulbo Raquídeo/patología , Degeneración Nerviosa , Vitamina E/uso terapéutico , Adolescente , Adulto , Axones/patología , Niño , Preescolar , Fibrosis Quística/complicaciones , Femenino , Humanos , Lactante , Masculino , Degeneración Nerviosa/efectos de los fármacos , Enfermedades del Sistema Nervioso/etiología , Enfermedades del Sistema Nervioso/patología , Enfermedades del Sistema Nervioso/prevención & control
14.
J Neuropathol Exp Neurol ; 35(5): 541-59, 1976.
Artículo en Inglés | MEDLINE | ID: mdl-182929

RESUMEN

A 60-year old man, eight weeks after being bitten on his finger by a stray cat, developed symptoms and signs of rabies which progressed rapidly over the next two weeks and he died of respiratory failure. Pathological examination revealed characteristic cytoplasmic inclusions in neurons of various parts of the central nervous system and the dorsal spinal and sympathetic ganglia. The diagnosis of rabies was confirmed by direct fluorescent antibody staining of the brain tissue obtained at autopsy. On histological examination, most, if not all, of the neuronal cytoplasmic inclusions were eosinophilic and homogeneous and lacked the basophilic inner granules or bodies characteristic of Negri bodies. Nevertheless, they were ultrastructurally identical with Negri bodies by virtue of being made up of finely fibrillar matrix and virus and/or related particles in varying numbers. This indicates that ultrastructurally typica Negri bodies may or may not have the histologically visible basophilic inner bodies depending upon the degree of virus replication. In light of the ultrastructural evidence, lyssa bodies described in rabies in the past may represent Negri bodies without histologically recognizable inner bodies or cytoplasmic inclusions unrelated to rabies, occurring ordinarily in normal or degenerating neurons. It is, therefore, suggested that the term, lyssa body, is obsolete and should no longer be used.


Asunto(s)
Cuerpos de Inclusión/ultraestructura , Rabia/patología , Corteza Cerebelosa/patología , Cuerpo Estriado/patología , Lóbulo Frontal/patología , Ganglios Espinales/ultraestructura , Hipocampo/ultraestructura , Humanos , Hipotálamo/patología , Masculino , Bulbo Raquídeo/patología , Persona de Mediana Edad , Lóbulo Parietal/patología , Puente/patología , Médula Espinal/patología , Sustancia Negra/ultraestructura , Lóbulo Temporal/patología , Tálamo/patología
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