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1.
Food Chem Toxicol ; 44(1): 138-45, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16095791

RESUMEN

Dunaliella carotene, extracted from dunaliella alga (Dunaliella bardawil or Dunaliella salina), for use as a food-coloring agent, has beta-carotene as its mainly constituent. As there have been no reports of toxicological evaluation, a 90-day subchronic toxicity study was here performed in F344 rats at dose levels of 0 (control), 0.63%, 1.25%, 2.5% and 5% in powdered basal diet. The average daily intakes of dunaliella carotene were 352, 696, 1420 and 2750 mg/kg/day, respectively, for males, and 370, 748, 1444 and 2879 mg/kg/day for females. No mortality or treatment-related clinical signs were observed throughout the experimental period in any of the groups. Body weight gain was slightly but significantly (p < 0.05) reduced from week 5 to the end of the experiment in 2.5% and 5% males. Increased PLT were observed in 1.25% and 5% males, and 2.5% and 5% females. Significant elevations or tendencies for increase in serum T. Cho and Ca were observed in all treated males and females, with clear dose-dependence in males. Organ weight measurement and histopathological observation revealed no toxicological changes. Based on growth suppression, no-observed-adverse-effect-levels (NOAELs) were estimated to be 1.25% (696 mg/kg/day) for males and 5% (2879 mg/kg/day) for females. As increases in serum Ca were observed in the lowest group in both sexes, a no-observed-effect level (NOEL) could not be determined in this study.


Asunto(s)
Chlorophyta/química , Colorantes de Alimentos/toxicidad , beta Caroteno/toxicidad , Administración Oral , Animales , Plaquetas/efectos de los fármacos , Calcio/sangre , Colesterol/sangre , Relación Dosis-Respuesta a Droga , Femenino , Colorantes de Alimentos/análisis , Masculino , Nivel sin Efectos Adversos Observados , Extractos Vegetales/análisis , Extractos Vegetales/toxicidad , Recuento de Plaquetas , Ratas , Ratas Endogámicas F344 , Pruebas de Toxicidad , Aumento de Peso/efectos de los fármacos , beta Caroteno/análisis
2.
Food Chem Toxicol ; 43(7): 1047-53, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15833380

RESUMEN

Agaricus blazei Murrill, an edible mushroom, is widely used as a functional food due to its possible medicinal effects. Aqueous extracts are also used as food additive to provide an agreeable bitter taste. As a part of its safety assessment, the present 90-day subchronic toxicity study was performed in F344 rats. To establish a no-observed-adverse-effect level (NOAEL), rats were fed powder diet containing A. blazei Murrill aqueous extract at dose levels of 0 (basal diet), 0.63, 1.25, 2.5 and 5% (maximum) for 90 days. During the experiment, there were no remarkable changes in general appearance and no deaths occurred in any experimental group. Although serum blood urea nitrogen was slightly but significantly increased in males of the 2.5 and 5% groups, no related histopathological changes were observed in the kidney, and serum creatinine levels were rather reduced, suggesting the increase of blood urea nitrogen to be of little toxicological significance. Hematology, organ weight measurement and histopathological observation revealed no test compound-related toxicological changes. In conclusion, A. blazei Murrill extract even at 5% in the diet (2654 mg/kgb.w./day for male rats and 2965 mg/kgb.w./day for female rats) did not cause remarkable adverse effects in F344 rats. Thus, the NOAEL was concluded to be 5% in the diet.


Asunto(s)
Agaricus/química , Medicamentos Herbarios Chinos/toxicidad , Animales , Análisis Químico de la Sangre , Peso Corporal/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ingestión de Alimentos/efectos de los fármacos , Femenino , Masculino , Tamaño de los Órganos , Ratas , Ratas Endogámicas F344
3.
Stroke ; 29(11): 2377-80, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9804652

RESUMEN

BACKGROUND AND PURPOSE: Pure hemisensory syndrome can be caused by small strokes occurring in a number of regions, including the thalamus and pons. Differentiation of the pontine sensory syndrome from the thalamic sensory syndrome has generally been made on the basis of distribution of sensory loss and involvement of specific sensory modalities but not without uncertainties and difficulties. Because the pontine tegmentum plays a pivotal role in generating horizontal eye movement, we attempted to discriminate these 2 syndromes by analyzing horizontal eye movements in stroke patients with pure hemisensory syndrome. METHODS: Horizontal saccade, pursuit, vestibulo-ocular reflex (VOR), and VOR cancellation (VORC) were evaluated using electro-oculography in 6 patients with hemisensory syndromes, 3 due to pontine stroke and 3 due to thalamic stroke, and all were verified by MRI or CT. In addition, somatosensory evoked potentials (SEPs) were recorded. RESULTS: Smooth pursuit and VORC directed toward the side of the lesion were impaired unilaterally in patients with pontine sensory stroke, whereas those 2 movements were intact bilaterally in patients with thalamic sensory stroke. Saccade and VOR were preserved in all patients. SEPs were normal in all patients with pontine and thalamic sensory strokes. No difference was found in the pattern of sensory disturbance between the 2 types of stroke patients. CONCLUSIONS: Ipsilateral impairment of the smooth pursuit system may be a sign of a pontine lesion in patients with hemisensory stroke.


Asunto(s)
Trastornos Cerebrovasculares/diagnóstico por imagen , Trastornos Cerebrovasculares/fisiopatología , Puente/fisiopatología , Movimientos Sacádicos/fisiología , Corteza Somatosensorial/fisiopatología , Trastornos Cerebrovasculares/complicaciones , Diagnóstico Diferencial , Electrooculografía , Potenciales Evocados Somatosensoriales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Parestesia/diagnóstico , Parestesia/etiología , Parestesia/fisiopatología , Puente/irrigación sanguínea , Radiografía , Reflejo Vestibuloocular , Corteza Somatosensorial/irrigación sanguínea , Corteza Somatosensorial/diagnóstico por imagen , Tálamo/citología , Tálamo/fisiopatología
4.
J Neurol Sci ; 161(2): 176-9, 1998 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-9879701

RESUMEN

An unusual combination of downgaze palsy and bilateral ptosis occurred in a patient with central nervous system lymphoma involving bilateral thalamus and midbrain tegmentum. Following treatment with corticosteroids, the transition from total paralysis of downgaze to the supranuclear form was noted, along with alleviation of ptosis, followed by complete resolution of both. The results of serial magnetic resonance images were consistent with our interpretation that his initial eye signs were caused by the combined involvement of the bilateral rostral interstitial nucleus of the medial longitudinal fasciculus (supranuclear downgaze palsy) and the oculomotor subnuclei (nuclear palsy of the inferior recti and levator palpebrae muscles).


Asunto(s)
Blefaroptosis/etiología , Fijación Ocular/fisiología , Lateralidad Funcional/fisiología , Mesencéfalo/fisiología , Oftalmoplejía/etiología , Tálamo/fisiología , Anciano , Humanos , Masculino
5.
Bioorg Med Chem Lett ; 8(16): 2209-12, 1998 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-9873514

RESUMEN

The whole structure of platycodin D is found to be essential to stimulate the volumetric increase in the pancreatic exocrine secretion, while the prosapogenins prepared from platycodin D increased only protein output of pancreatic juice.


Asunto(s)
Páncreas/metabolismo , Saponinas/química , Saponinas/farmacología , Triterpenos , Animales , Conformación de Carbohidratos , Secuencia de Carbohidratos , Datos de Secuencia Molecular , Estructura Molecular , Páncreas/efectos de los fármacos , Raíces de Plantas , Plantas Medicinales , Ratas , Saponinas/aislamiento & purificación , Relación Estructura-Actividad
6.
Planta Med ; 63(5): 419-24, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9342945

RESUMEN

Our previous report stated that kikyo-to, a Japanese herbal medicine, consisting of the roots of Platycodon grandiflorum and Glycyrrhiza sp., stimulates the pancreatic exocrine secretion of conscious rats. The present study focused on the effective components of kikyo-to and the mechanism of stimuli to pancreatic secretion of rats. When 10 to 100 mg of platycodin D, a saponin from the root of Platycodon grandiflorum, was intragastrically administered, the pancreatic secretion of rats was stimulated. At the same time, the plasma CCK concentration increased. On the other hand, the stimulative effects of glycyrrhizin, a saponin from the root of Glycyrrhiza sp. were weak compared to platycodin D. The effects of 10 mg/kg of platycodin D on pancreatic secretion were inhibited by loxiglumide (50 mg/kg, i.g.), a CCK receptor antagonist. In contrast, the suppressive effect of atropine (300 micrograms/kg/h, i.v.) on pancreatic secretion was reduced by administering 10 mg/kg of platycodin D. In addition, up to 1 mM of platycodin D did not inhibit the trypsin activities in vitro. In conclusion, kikyo-to serves to stimulate pancreatic exocrine secretion mainly because platycodin D causes gastrointestinal hormones, particularly, CCK to be released from the duodenum.


Asunto(s)
Gabexato/análogos & derivados , Páncreas/metabolismo , Jugo Pancreático/metabolismo , Plantas Medicinales , Saponinas/farmacología , Triterpenos , Animales , Atropina/farmacología , Colecistoquinina/metabolismo , Duodeno/fisiología , Ésteres , Ácido Glicirrínico/farmacología , Guanidinas/farmacología , Japón , Masculino , Páncreas/efectos de los fármacos , Jugo Pancreático/efectos de los fármacos , Extractos Vegetales , Raíces de Plantas , Proglumida/análogos & derivados , Proglumida/farmacología , Ratas , Ratas Wistar , Receptores de Colecistoquinina/antagonistas & inhibidores , Saponinas/aislamiento & purificación , Tripsina/metabolismo , Inhibidores de Tripsina/farmacología
7.
J Anal Toxicol ; 20(5): 318-22, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8872242

RESUMEN

A sensitive method for simultaneous determination of ester-type local anesthetic drugs (procaine, tetracaine, and T-caine) has been developed using wide-bore capillary gas chromatography with nitrogen-phosphorus detection (GC-NPD). The extraction procedure, the experimental conditions for heptafluorobutyryl (HFB) derivative formation, and the percentage of the ester-type local anesthetic drugs from the human serum are described. The HFB derivatives of ester-type local anesthetic drugs showed sensitivity of approximately 2-3 fold higher than that without derivatization. The detection limits of HFB derivatives of the ester-type local anesthetic drugs were approximately 60-70 pg on column. Recoveries from the human serum were 85-94%. This method could be used to determine concentrations as low as 24-28 ng/mliters of the ester-type local anesthetic drugs.


Asunto(s)
Anestésicos Locales/análisis , Procaína/análisis , Tetracaína/análisis , para-Aminobenzoatos , Ácido 4-Aminobenzoico/análisis , Ácido 4-Aminobenzoico/sangre , Anestésicos Locales/sangre , Humanos , Nitrógeno/química , Fósforo/química , Procaína/sangre , Sensibilidad y Especificidad , Solventes/química , Tetracaína/sangre
8.
Leuk Res ; 19(8): 549-56, 1995 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7658701

RESUMEN

A low concentration of bufalin, a component of bufadienoides in the traditional Chinese medicine chan'su, was shown previously to induce differentiation of a broad range of human leukemia cell lines. In the present study, we found that bufalin at concentrations of 10(-7) M and higher induced apoptosis in human leukemia cells, such as HL60, ML1, but not in mouse leukemia M1 cells. A mere 15 min pretreatment of HL60 cells with 10(-6) M bufalin, followed by incubation for 15 h without bufalin, caused fragmentation of DNA and a decrease in cell viability, indicating that the signal for induction of apoptosis is triggered rapidly upon treatment with bufalin. Bufalin-induced apoptosis in HL60 cells was inhibited by ZnCl2, an inhibitor of endonuclease, but not by cycloheximide, an inhibitor of protein synthesis. Northern blot analysis revealed that the levels of expression of the c-myc and bcl-2 genes in HL60 cells decreased with time after treatment with bufalin. These results suggest that bufalin induces apoptosis specifically in human leukemia cells by altering the expression of these genes involved in apoptosis.


Asunto(s)
Apoptosis/efectos de los fármacos , Bufanólidos/farmacología , Genes myc , Proteínas Proto-Oncogénicas/genética , Animales , Afidicolina/farmacología , Cicloheximida/farmacología , Daño del ADN , Expresión Génica/efectos de los fármacos , Humanos , Ratones , Proteínas Proto-Oncogénicas c-bcl-2 , Proteínas Proto-Oncogénicas c-myb , ARN Mensajero/genética , ARN Neoplásico/genética , Células Tumorales Cultivadas/efectos de los fármacos , Zinc/farmacología
9.
Jpn J Cancer Res ; 85(6): 645-51, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8063619

RESUMEN

We found that bufalin, an active principle of the Chinese medicine chan'su, has selective inhibitory effects on the growth of various human cancer cells. In order to examine whether the growth-inhibitory effect of bufalin on human cancer cells is associated with apoptosis, human leukemia cells were treated with bufalin. HL-60, ML1, and U937 leukemia cells treated with bufalin at 10(-8) M and above had condensed and fragmented nuclei. Flow cytometric analysis of these cells treated with bufalin showed fragmented DNA smaller than that of the G1 phase. DNA of HL-60 cells treated with bufalin showed a ladder pattern characteristic of apoptosis, as analyzed by agarose gel electrophoretic analysis. DNA synthesis and topoisomerase II activity of HL-60 cells were markedly inhibited as the concentration of bufalin was increased. The concentration needed for inducing apoptosis of HL-60 cells was 10(-8) M, which is comparable to that of camptothecin, but lower than those of other antitumor drugs such as cisplatin, VP16 and all-trans retinoic acid. Apoptosis was not observed when human mononuclear and polymorphonuclear cells were treated with 10(-6) M bufalin for 24 h. These results indicate the association of the growth-inhibitory effect of bufalin with the induction of apoptosis, at least in HL-60 cells, and suggest the usefulness of bufalin for differentiation-apoptosis-inducing therapy for cancer.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Bufanólidos/farmacología , Leucemia Mieloide/tratamiento farmacológico , Materia Medica/farmacología , Muerte Celular/efectos de los fármacos , División Celular/efectos de los fármacos , ADN de Neoplasias/análisis , ADN de Neoplasias/biosíntesis , Electroforesis en Gel de Agar , Células HeLa , Humanos , Cinética , Leucemia Mieloide/metabolismo , Leucemia Mieloide/patología , Leucocitos Mononucleares/química , Leucocitos Mononucleares/metabolismo , Proteínas de Neoplasias/biosíntesis , Neutrófilos/química , Neutrófilos/metabolismo , ARN Neoplásico/biosíntesis , Células Tumorales Cultivadas/efectos de los fármacos
10.
J Nutr Sci Vitaminol (Tokyo) ; 40(2): 105-13, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7931719

RESUMEN

The alteration in the metabolic activation of N-nitrosodimethylamine (NDMA) was investigated in the rat during dietary pyridoxine deficiency. The in vitro metabolism of NDMA by demethylase system was measured in both liver and kidney microsomes. The profile of the kidney enzyme appears similar to that of the liver indicating that at least two forms of isozymes with the low and the high Km's are present. Pyridoxine deficiency significantly increased the activity of NDMA-demethylase of both organs. The increase in the activity of NDMA-demethylase induced by dietary pyridoxine deficiency can be reversed by supplementation of pyridoxine (500 micrograms), i.p., daily for two consecutive days. The increase in the NADPH cytochrome c reductase activity was observed after 6 weeks on pyridoxine-deficient diet.


Asunto(s)
Sistema Enzimático del Citocromo P-450/metabolismo , Dimetilnitrosamina/metabolismo , Oxidorreductasas N-Desmetilantes/metabolismo , Deficiencia de Vitamina B 6/enzimología , Animales , Citocromo P-450 CYP2E1 , Riñón/enzimología , Cinética , Masculino , Microsomas/enzimología , Microsomas Hepáticos/enzimología , Ratas , Ratas Endogámicas F344
11.
Mutat Res ; 297(1): 53-60, 1993 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7686273

RESUMEN

Pine cone extract fraction VI (PC-VI) inhibited the mutagenicity of the promutagens tested: the polycyclic aromatic hydrocarbon benzo[a]pyrene (B[a]P) dose-dependently, and the aromatic amines 2-aminoanthracene (AA) and 2-acetylaminofluorene (AAF) at high concentrations. PC-VI had no effect on the mutagenicity of the direct-acting mutagens 2-(2-furyl)-3-(5-nitrofuryl)acrylamide (AF-2) and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), but inhibited the mutagenicity of the direct-acting mutagen N-hydroxy 2-acetylaminofluorene (N-OH AAF, proximate mutagen of AAF). The addition of PC-VI to rat hepatic microsomes resulted in a decrease of their enzyme activities, especially NADPH-cytochrome c reductase. By gas-chromatographic analysis of B[a]P or AA contents after incubation of B[a]P or AA and PC-VI and S9 mix, the inhibition of hepatic metabolizing enzymes and the interaction between AA and PC-VI were confirmed. On the other hand, PC-VI had no effect on the DNA repair systems for B[a]P- or AA-induced mutagenesis. We conclude that PC-VI shows indirect antimutagenicity by interfering with cytochrome P-450-dependent bioactivation and by direct interaction with AA and the proximate mutagenic product of AAF.


Asunto(s)
Antimutagênicos/farmacología , Extractos Vegetales/farmacología , 2-Acetilaminofluoreno/antagonistas & inhibidores , 2-Acetilaminofluoreno/toxicidad , Animales , Antracenos/metabolismo , Antracenos/toxicidad , Benzo(a)pireno/metabolismo , Benzo(a)pireno/toxicidad , Técnicas In Vitro , Lignina/farmacología , Masculino , Metilnitronitrosoguanidina/metabolismo , Metilnitronitrosoguanidina/toxicidad , Microsomas Hepáticos/enzimología , Peso Molecular , Pruebas de Mutagenicidad , Extractos Vegetales/química , Ratas , Ratas Sprague-Dawley
12.
J Toxicol Sci ; 18(1): 11-9, 1993 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8386258

RESUMEN

Selectivity of lead effect to phenylethanolamine N-methyltransferase (PNMT) activity in regions of brain from rats postnatally exposed to lead was tested. Three groups of animals were prepared; (1) Rats exposed to lead at a low dose (0.05% PbAcetate: PbAc); (2) Rats exposed to lead at a high dose (0.2% PbAc); (3) Age-matched normal control rats. At 2, 4, 6 and 8 weeks of age weight of whole brain and body in each group were measured. At the same ages activities of PNMT and Na+/K(+)-ATPase were examined on 4 brain regions of each animal. Exposure of rats to lead generally decreased activity of Na+/K(+)-ATPase and showed alternative change of those of PNMT. Brain regions where changes of PNMT activity were detected without concomitant changes of Na+/K(+)-ATPase activity, were telencephalon and pons/medulla at 2 weeks of age and telencephalon at 4 weeks of age in rats exposed to lead at a low dose, and those in rats exposed to lead at a high dose were pons/medulla at 8 weeks of age. These data imply that adrenergic nervous system in the brain regions described above could selectively be affected by lead.


Asunto(s)
Encéfalo/efectos de los fármacos , Plomo/toxicidad , Feniletanolamina N-Metiltransferasa/metabolismo , Factores de Edad , Animales , Encéfalo/enzimología , Relación Dosis-Respuesta a Droga , Feniletanolamina N-Metiltransferasa/efectos de los fármacos , Ratas , Ratas Wistar , ATPasa Intercambiadora de Sodio-Potasio/efectos de los fármacos , ATPasa Intercambiadora de Sodio-Potasio/metabolismo
13.
J Toxicol Sci ; 18(1): 21-9, 1993 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8386259

RESUMEN

Selectivity of lead effect on dopamine beta-hydroxylase activity in regions of brai nfrom rats postnatally exposed to lead was tested. Three groups of animals were prepared; (1) Rats exposed to lead at a low dose (0.05% PbAcetate: PbAc); (2) Rats exposed to lead at a high dose (0.2% PbAc); (3) Age-matched normal control rats. At 2, 4, 6 and 8 weeks of age weight of whole brain and body in each group were measured. At the same ages activities of dopamine beta-hydroxylase and Na+K(+)-ATPase were measured in 5 brain regions of each animal. Exposure of rats to lead generally decreased Na+/K(+)-ATPase activity and showed alternative changes of dopamine beta-hydroxylase activity were detected without concomitant changes of Na+/K(+)-ATPase activity were telencephalon and pons/medulla at 2 weeks of age and telencephalon, diencephalon and pons/medulla at 4 weeks of age and midbrain and pons/medulla at 6 weeks of age and cerebellum at 8 weeks of age in rats exposed to lead at a low dose, and those in rats exposed to lead at a high dose were midbrain at 6 weeks of age and cerebellum at 8 weeks of age. These data imply that noradrenergic nervous system in the brain regions described above could selectively be affected by lead.


Asunto(s)
Encéfalo/efectos de los fármacos , Dopamina beta-Hidroxilasa/metabolismo , Plomo/toxicidad , Factores de Edad , Animales , Encéfalo/enzimología , Dopamina beta-Hidroxilasa/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Femenino , Masculino , Ratas , Ratas Wistar , ATPasa Intercambiadora de Sodio-Potasio/efectos de los fármacos , ATPasa Intercambiadora de Sodio-Potasio/metabolismo
14.
J Toxicol Sci ; 17(4): 197-210, 1992 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1361952

RESUMEN

Alterations of tyrosine hydroxylase activity in various regions of brain from rats postnatally exposed to lead were tested. Three groups of animals were prepared; (1) Rats exposed to lead at a low dose (0.05% lead acetate, PbAc); (2) Rats exposed to lead at a high dose (0.2% PbAc); (3) Age-matched normal control rats. At 2, 4, 6, and 8 weeks of age, weight of brain and body, and concentrations of lead in whole brain of animals in each group were measured. Activities of tyrosine hydroxylase and Na(+)-K+ ATPase were also measured at the same ages in 4 brain regions of each animal. Body weight gain was decreased after 6 weeks of age in rats exposed to lead at a high dose. Concentrations of lead in whole brain were increased from 0.37 to 0.83 (ng/mg wet tissue) in these animals. Exposure of rats to lead generally increased tyrosine hydroxylase activity and decreased Na(+)-K+ ATPase activity. However, changes of tyrosine hydroxylase activity were detected without concomitant changes of Na(+)-K+ ATPase activity in pons-medulla at 2 weeks of age and telencephalon at 6 weeks of age in rats exposed to lead at a low dose, and in midbrain at 4 and 6 weeks of age in rats exposed to lead at a high dose. These data imply that catecholaminergic nervous system in the brain regions described above could be selectively affected by lead.


Asunto(s)
Diencéfalo/enzimología , Intoxicación por Plomo/enzimología , Puente/enzimología , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Telencéfalo/enzimología , Tirosina 3-Monooxigenasa/metabolismo , Animales , Femenino , Masculino , Ratas , Ratas Wistar
15.
Drug Metab Dispos ; 20(1): 52-5, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1346996

RESUMEN

The enzyme system mediating the deacetylation of cinobufagin (CB) at the 16-position to give deacetylCB was characterized in the rat. Tissue distribution studies showed that the highest activity of CB deacetylation was mainly localized in the liver microsomal fraction. Some activity was also detected in the serum and intestine. Kinetic studies of the enzymatic reaction carried out by microsomes demonstrated that the formation of deacetyl-CB increased linearly with time up to 60 min and with protein content up to 10 mg. Apparent Km and Vmax values calculated from Lineweaver-Burk plots were 2.7 x 10(-4) M and 4.17 nmol/mg of protein/min, respectively. Low concentrations of several metal salts (AgNO3, MgCl2, CoSO4, and CuCl2) did not affect CB deacetylase activity. Microsomal CB deacetylation was inhibited by the organophosphorus compounds cyanox and fenitrothion at 1.0 x 10(-6) M. Eserine sulfate, disulfiram, rifampicin, and phenacetin at 1.0 x 10(-4) M also decreased CB deacetylase activity. Aspirin, sodium fluoride, and EDTA at 1.0 x 10(-3) M did not inhibit the deacetylation. In vivo treatment of rats with phenobarbital resulted in a 2-fold increase in microsomal CB deacetylase activity. All of these results suggest that the enzyme responsible for CB deacetylation is somewhat different from the other characterized esterases.


Asunto(s)
Amidohidrolasas/metabolismo , Bufanólidos/metabolismo , Medicamentos Herbarios Chinos/metabolismo , Microsomas Hepáticos/metabolismo , Acetilación/efectos de los fármacos , Animales , Cromatografía Líquida de Alta Presión , Estabilidad de Medicamentos , Estabilidad de Enzimas , Esterasas/antagonistas & inhibidores , Concentración de Iones de Hidrógeno , Cinética , Espectroscopía de Resonancia Magnética , Masculino , Microsomas Hepáticos/efectos de los fármacos , Microsomas Hepáticos/enzimología , Mitocondrias Hepáticas/efectos de los fármacos , Mitocondrias Hepáticas/enzimología , Mitocondrias Hepáticas/metabolismo , Especificidad de Órganos , Fenobarbital/farmacología , Ratas , Ratas Endogámicas , Distribución Tisular
16.
Drug Metab Dispos ; 19(5): 917-9, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1686236

RESUMEN

The metabolism of cinobufagin (CB) in rat liver microsomes was studied. By comparison of retention times and fragmentation patterns obtained by thermospray LC/MS with those of authentic standards, four metabolites of CB were also identified, in addition to deacetylCB (M1) and 3-epideacetylCB (M2), which have been reported previously. The additional four metabolites were identified to be 3-epiCB (M4), 3-ketoCB (M5), 3-keto-16 beta-OH-deacetylCB (M3), and 3-keto-16 alpha-OH-deacetylCB (M6). The primary metabolic products of CB were M1 and M2, with a small amount of M4 and trace amounts of M3, M5, and M6. These results indicate that major metabolic routes of CB were deacetylation at the 16-position and epimerization at the 3-position via the 3-keto intermediate.


Asunto(s)
Bufanólidos/metabolismo , Medicamentos Herbarios Chinos/metabolismo , Microsomas Hepáticos/metabolismo , Acilación , Animales , Cromatografía Liquida , Masculino , Espectrometría de Masas , Estructura Molecular , Ratas , Ratas Endogámicas , Estereoisomerismo
17.
Biochem Biophys Res Commun ; 178(2): 686-93, 1991 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-1859424

RESUMEN

Bufalin was found to be a potent inducer of differentiation in human erythroleukemia K562 cells by examination of various differentiation markers (as assessed by the morphology, histochemistry, and the abilities to phagocytose latex particles, to reduce nitro-blue tetrazolium and to develop Fc receptors). Bufalin, at a concentration as low as 10 nM, also produced a strong differentiation-inducing activity in three other human leukemia-derived cell lines (human promyelocytic HL60, monoblastic U937 and myeloblastic ML1). Treatment of K562 cells with other cardiotonic steroids, such as cinobufagin, ouabain and digitoxigenin, at the concentration of 10 nM for four days resulted in weak or no effect on the cells. These findings suggest that bufalin might have potentiality as a new agent in the differentiation therapy for human myelogenous leukemia.


Asunto(s)
Bufanólidos/farmacología , Diferenciación Celular/efectos de los fármacos , Bufanólidos/química , Línea Celular , Digitoxigenina/farmacología , Relación Dosis-Respuesta a Droga , Medicamentos Herbarios Chinos/farmacología , Humanos , Cinética , Leucemia Mielógena Crónica BCR-ABL Positiva , Materia Medica , Estructura Molecular , Ouabaína/farmacología
18.
Anticancer Res ; 11(2): 881-8, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1648335

RESUMEN

Several antitumor substances that effectively inhibited the growth of ascites and solid tumor cells transplanted in mice were isolated from pine cone NaOH extract by acid- and ethanol-precipitation. These antitumor substances were also potent antiviral agents against human immunodeficiency virus, herpes simplex virus and influenza virus; they induced antimicrobial activity against Staphylococcal aureus, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae and Candida albicans, and induced antiparasite activity against Hymenolepis nana in mice. Chemical analysis of these substances by IR, UV, NMR, ESR and partition chromatography on cellulose-TLC plate disclosed that they had lignin-related structures complexed with sugars or polysaccharides. Chlorinated decomposition of the lignin portion significantly reduced their antiviral activity. In agreement with this, the antiviral activity of synthesized lignins prepared by polymerization of phenylpropanoid precursors was comparable to that of the undecomposed counterparts of the pine cone extract. Acid hydrolysis of the polysaccharide portion significantly reduced the ability of the substances to induce antitumor and antimicrobial activities in mice. With an appropriate eliciting agent, intravenous administration of natural lignified substances transiently induced endogenous production of a cytotoxic factor (possibly tumor necrosis factor) in normal mice. Their priming activity was significantly higher than that of their component units or degradation products. These data suggest the importance of conjugating lignins with polysaccharides for in vivo expression of various kinds of immunopotentiating activity. As possible explanations for their induction of a variety of immunopotentiating activities, these natural and synthetic lignins stimulated macrophage NBT-reducing activity, polymorphonuclear cell (PMN) iodination and splenocyte DNA synthesis and inhibited poly (ADP-ribose) glycohydrolase, RNA-dependent DNA polymerase (reverse transcriptase) and RNA-dependent RNA polymerase activities.


Asunto(s)
Adyuvantes Inmunológicos , Antineoplásicos , Antivirales , Lignina/farmacología , Extractos Vegetales/farmacología , Animales , VIH/efectos de los fármacos , Lignina/uso terapéutico , Neoplasias Experimentales/tratamiento farmacológico , Orthomyxoviridae/efectos de los fármacos , Extractos Vegetales/uso terapéutico , Extractos Vegetales/toxicidad , Simplexvirus/efectos de los fármacos , Árboles
20.
Neurology ; 29(8): 1188-90, 1979 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-572512

RESUMEN

Recently, acupuncture has been widely performed for the treatment of many different diseases. We studied a patient with migraine who had been treated by "okibari," an acupunctural procedure. About 20 needles were inserted permanently in the subcutaneous tissues of his neck and occipital scalp. About 6 months later he hit the back of his neck, and soon after this accident cervical myelopathy occurred. There have been no similar reports.


Asunto(s)
Terapia por Acupuntura/efectos adversos , Traumatismos de la Médula Espinal/etiología , Adulto , Humanos , Masculino , Agujas , Radiografía , Traumatismos de la Médula Espinal/diagnóstico por imagen
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