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1.
J Sports Med Phys Fitness ; 54(5): 622-30, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25270782

RESUMEN

BACKGROUND: Aim of the present study was to compare the effects of highly branched cyclic dextrin (HBCD) drink with a glucose-based control drink on immunoendocrine responses to endurance exercise. METHODS: Using a randomized, double-blind placebo-controlled cross-over design, seven male triathletes participated in two duathlon races separated by one month, consisting of 5 km of running, 40 km of cycling and 5 km of running. In the first race, four athletes consumed the HBCD-based drink and three athletes consumed the glucose-based drink. In the second race, three athletes consumed the HBCD-based drink and four athletes consumed the glucose-based drink. We collected blood and urine samples before and after the races to analyze leukocyte count and concentrations of hormones and cytokines. RESULTS: Lymphocyte and neutrophil counts increased significantly after exercise in both trials (P<0.05), but were not significantly different between the trials. Plasma noradrenalin concentration increased significantly (P<0.05) during exercise in the glucose trial, but not in the HBCD trial. Plasma concentrations of interleukin (IL)-8 and IL-10 increased significantly during exercise in both trials (P<0.05) but were not significantly different between the trials. Post-race urinary IL-8, IL-10 and IL-12p40 concentrations were significantly lower in the HBCD trial compared with the glucose trial (P<0.05), although the plasma concentrations of these cytokines were not significantly different between both trials. CONCLUSION: These results suggest that the HBCD-based drink may attenuate the stress hormone response, and reduce the urinary cytokine levels following exhaustive exercise.


Asunto(s)
Bebidas , Ciclodextrinas/administración & dosificación , Citocinas/sangre , Citocinas/orina , Suplementos Dietéticos , Resistencia Física/fisiología , Adulto , Ciclismo/fisiología , Método Doble Ciego , Epinefrina/sangre , Pruebas Hematológicas , Humanos , Masculino , Norepinefrina/sangre , Carrera/fisiología , Adulto Joven
2.
Caries Res ; 44(3): 253-9, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20516685

RESUMEN

Remineralization is the process by which hydroxyapatite (HAp) is restored in enamel subsurface lesions, and transversal microradiography (TMR) has been used to analyze remineralization in terms of the recovery of mineral content. In this study, we directly detected the distribution and orientation of longitudinal HAp crystallite at the remineralized zone in enamel subsurface lesions by using an X-ray microbeam (6-mum diameter) diffraction method. This method was demonstrated and involves the simultaneous detection of wide-angle X-ray diffraction (WAXRD) and small-angle X-ray scattering (SAXS). WAXRD reflects the amount of HAp crystallites, and SAXS reflects that of voids in crystallites. The polished surface of a bovine enamel block was divided into three zones of sound, demineralized, and remineralized zones. Thin sections of approximately 150 mum thickness were then cut perpendicular to the surface, and subjected to WAXRD and SAXS following TMR. The increase in the amount of HAp crystallites and the decrease in voids in the crystallites at the remineralized zone were detected by WAXRD and SAXS, respectively, which was consistent with the result of TMR. This study indicates that both the spatial distribution and orientation of the restored HAp crystals in the remineralization process at the subsurface lesion can be simultaneously analyzed by the X-ray diffraction methods.


Asunto(s)
Esmalte Dental/química , Durapatita/química , Remineralización Dental , Animales , Bovinos , Cristalización , Cristalografía por Rayos X/métodos , Esmalte Dental/patología , Microrradiografía
3.
J Synchrotron Radiat ; 16(Pt 3): 398-404, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19395806

RESUMEN

Early caries lesion is a demineralization process that takes place in the top 0.1 mm layer of tooth enamel. In this study, X-ray microbeam diffraction was used to evaluate the hydroxyapatite crystallites in the subsurface lesion of a bovine enamel section and the results are compared with those obtained by transversal microradiography, a method commonly used for evaluation of tooth mineral. Synchrotron radiation from SPring-8 was used to obtain a microbeam with a diameter of 6 microm. Wide-angle X-ray diffraction reports the amount of hydroxyapatite crystals, and small-angle X-ray scattering reports that of voids in crystallites. All three methods showed a marked decrease in the enamel density in the subsurface region after demineralization. As these diffraction methods provide structural information in the nanometre range, they are useful for investigating the mechanism of the mineral loss in early caries lesion at a nanometre level.


Asunto(s)
Esmalte Dental/diagnóstico por imagen , Esmalte Dental/ultraestructura , Difracción de Rayos X/métodos , Animales , Bovinos , Técnicas In Vitro , Radiografía , Propiedades de Superficie
4.
Thorac Cardiovasc Surg ; 57(8): 496-7, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20013628

RESUMEN

Thymoma is the most common neoplasm in the anterior mediastinum. This report presents an extremely rare case of a type A thymoma with Masaoka's stage IV b due to lymph node metastasis. In 1997, a 59-year-old man underwent complete resection of a stage IV b type A thymoma with postoperative radiotherapy to the mediastinum. In 2006, small nodules were detected in the anterior mediastinum and above the right diaphragm and tumor resection was performed. The two lesions were both histologically diagnosed as recurrences of the type A thymoma. There has been no evidence of recurrence 15 months after the second surgery.


Asunto(s)
Recurrencia Local de Neoplasia/cirugía , Timoma/cirugía , Neoplasias del Timo/cirugía , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Reoperación , Sobrevivientes , Timoma/patología , Neoplasias del Timo/patología , Resultado del Tratamiento
5.
Int J Food Sci Nutr ; 60 Suppl 5: 106-13, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19462324

RESUMEN

We studied the psychological stress-reducing effect of chocolate enriched with gamma-aminobutyric acid (GABA), on stress induced by an arithmetic task using changes of heart rate variability (HRV) and salivary chromogranin A (CgA). Subjects ingested 10 g chocolate enriched with 28 mg GABA (GABA chocolate); 15 min after the ingestion, subjects were assigned an arithmetic task for 15 min. After the task, an electrocardiogram was recorded and saliva samples were collected. HRV was determined from the electrocardiogram, and the activity of the autonomic nervous system was estimated through HRV. The CgA concentration of all saliva samples, an index for acute psychological stress, was measured. From HRV, those taking GABA chocolate made a quick recovery to the normal state from the stressful state. The CgA value after the task in those taking GABA chocolate did not increased in comparison with that before ingestion. From these results, GABA chocolate was considered to have a psychological stress-reducing effect.


Asunto(s)
Cacao , Dulces , Alimentos Funcionales , Estrés Psicológico/prevención & control , Ácido gamma-Aminobutírico/administración & dosificación , Adulto , Algoritmos , Sistema Nervioso Autónomo/fisiopatología , Cacao/química , Cromogranina A/metabolismo , Estudios Cruzados , Método Doble Ciego , Frecuencia Cardíaca , Hemodinámica , Humanos , Masculino , Saliva/metabolismo , Análisis y Desempeño de Tareas , Factores de Tiempo
6.
Kyobu Geka ; 61(13): 1114-7, 2008 Dec.
Artículo en Japonés | MEDLINE | ID: mdl-19068697

RESUMEN

We herein describe an extremely rare case of pulmonary granuloma possibly caused by a fish bone material. A 60-year-old woman with hemosputum was found to have a right pulmonary nodule. Chest computed tomography showed a nodule with pleural retraction, vascular convergence and ground glass opacity, measuring 23 mm in diameter, located at the S2 Of right upper lobe. Based on these findings, this nodule was considered to be a primary lung cancer, and pulmonary resection was performed. Macroscopically, a foreign material was found in the lesion and the pathologic diagnosis of the nodule was foreign body granuloma possibly due to a fish bone material.


Asunto(s)
Granuloma de Cuerpo Extraño/etiología , Enfermedades Pulmonares/etiología , Animales , Huesos , Femenino , Peces , Granuloma de Cuerpo Extraño/diagnóstico , Humanos , Enfermedades Pulmonares/diagnóstico , Persona de Mediana Edad
7.
Biochim Biophys Acta ; 557(1): 243-7, 1979 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-549640

RESUMEN

The permeabilities of sarcoplasmic reticulum vesicle membrane for various ions and neutral molecules were measured by following the change in light scattering intensity due to the osmotic volume change of the vesicles. 4-Acetoamido-4'-isothiocyanostilbene-2,2'-disulfonate (SITS), which is a potent inhibitor for the anion permeability of red blood cells membrane, inhibited the permeability of sarcoplasmic reticulum for anions such as Cl-, Pi and methanesulfonate, while it slightly increased that for cations and neutral molecules such as Na+, K+, choline and glycerol. Binding of 5 mumol SITS/g protein was necessary for the inhibition of anion permeability. These results suggest the existence of a similar anion transport system in sarcoplasmic reticulum membrane as revealed in red blood cell membrane.


Asunto(s)
Ácido 4-Acetamido-4'-isotiocianatostilbeno-2,2'-disulfónico/farmacología , Aniones/metabolismo , Retículo Sarcoplasmático/metabolismo , Estilbenos/farmacología , Animales , Transporte Biológico/efectos de los fármacos , Cationes/metabolismo , Membrana Eritrocítica/metabolismo , Luz , Permeabilidad , Unión Proteica , Conejos , Dispersión de Radiación
8.
Biochim Biophys Acta ; 413(3): 415-24, 1975 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-127623

RESUMEN

1. Proteolipid was extracted from the electric organ of Narke japonica by using chloroform/methanol (2:1, v/v). This extract was separated into acetylcholine-binding and non-binding substances by column chromatography. However, acetylcholine-binding substances did not show the characteristic properties of protein. 2. The membrane fragments of the electric organ were separated into three main parts by sucrose density gradient centrifugation. From the heaviest, the fractions were acetylcholine receptor rich, ATPase rich, and acetylcholinesterase rich. 3. The membrane fraction having acetylcholine receptor showed the excitability, the increase of Na+ permeability by the application of cholinergic agonists. However, the acetylcholine binding substance extracted by the organic solvent was richer in the lighter fraction. This substance differed from the true acetylcholine receptor.


Asunto(s)
Acetilcolina/metabolismo , Órgano Eléctrico/metabolismo , Receptores Colinérgicos , Acetilcolinesterasa/análisis , Adenosina Trifosfatasas/análisis , Animales , Sitios de Unión , Transporte Biológico Activo , Membrana Celular/análisis , Membrana Celular/metabolismo , Peces , Lipoproteínas/aislamiento & purificación , Lipoproteínas/metabolismo , Proteínas del Tejido Nervioso/aislamiento & purificación , Proteínas del Tejido Nervioso/metabolismo , Sodio/metabolismo
9.
J Med Chem ; 20(7): 976-8, 1977 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17753

RESUMEN

N-Alkyl derivatives of B/C-cis- and B/C-trans-6-hydroxy-1,3,4,9,10,10a-hexahydro-2H-10,4a-methanoimino-ethanophenanthrene have been prepared. The analgesic potency and physical dependence capacity of these compounds were determined. The N-methyl derivatives were analgesically equipotent with morphine. None of these compounds except the N-methyl-B/C-trans isomer 2b suppressed or precipitated the abstinence syndrome. Compound 2b was a narcotic agonist. The N-methyl-B/C-cis compound 2a appears to warrant further examination for its potential as a potent analgesic having no physical dependence liability.


Asunto(s)
Analgésicos/síntesis química , Morfinanos/síntesis química , Analgésicos Opioides/síntesis química , Animales , Haplorrinos , Macaca mulatta , Ratones , Conformación Molecular , Morfinanos/farmacología , Tiempo de Reacción/efectos de los fármacos , Relación Estructura-Actividad
10.
J Med Chem ; 19(6): 803-6, 1976 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7674

RESUMEN

Six 10-hydroxy-4-methyl-2,3,4,5,6,7-hexahydro-1,6-methano-1H-4-benzazonine derivatives 17a-f have been synthesized as potential analgesics. The synthesis of these compounds involved conversion of 4-(2-dimethylaminoethyl)-6-methoxy alpha tetralone derivatives 12a-f to their N-methyl analogues and the subsequent intramolecular mannich reaction with formaldehyde to give the 7-keto C-ring homobenzomorphans 14a-f from which 17a-f, respectively, were obtained. Compounds 17a-f are as potent as morphine as analgesics (mice).


Asunto(s)
Analgésicos Opioides/síntesis química , Benzomorfanos/síntesis química , Morfinanos/síntesis química , Animales , Benzomorfanos/análogos & derivados , Benzomorfanos/farmacología , Benzomorfanos/toxicidad , Codeína/farmacología , Dosificación Letal Mediana , Espectroscopía de Resonancia Magnética , Masculino , Ratones , Morfina/farmacología , Tiempo de Reacción/efectos de los fármacos , Relación Estructura-Actividad
11.
J Med Chem ; 20(2): 310-2, 1977 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-836505

RESUMEN

Three 1,3-dimethyl-9-hydroxy-1,2,3,4,5,6-hexahydro-1,5-methano-3-benzazocine derivatives (7-9) have been synthesized and tested as analgesics. The synthesis of these compounds involved conversion of 1-methyl-7-methoxy-beta-tetralone (1) by Mannich reaction with MeNH2 and HCHO to give the 11-ketone 2, from which 7,8, and 9, respectively, were obtained. These compounds have analgesic activity, and 7 was found to be comparable to codeine.


Asunto(s)
Analgésicos/síntesis química , Azocinas/síntesis química , Animales , Azocinas/farmacología , Hidrocarburos Aromáticos con Puentes/síntesis química , Hidrocarburos Aromáticos con Puentes/farmacología , Masculino , Ratones , Tiempo de Reacción/efectos de los fármacos
12.
J Med Chem ; 21(11): 1105-10, 1978 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-722717

RESUMEN

The benzomorphan analogues, 8-hydroxy-3-methyl-2,3,4,5-tetrahydro-1,4-methano-1H-3-benzazepine (1), 8-hydroxy-2-methyl-2,3,4,5-tetrahydro-1,4-methano-1H-2-benzazepine (2), 9-hydroxy-2-methyl-1,2,3,4,5,6-hexahydro-1,5,-methano-2-benzazocine (3), and 10-hydroxy-2-methyl-2,3,4,5,6,7-hexahydro-1,6-methano-1H-2-benzazonine (4), have been synthesized in order to evaluate their analgetic activity. Only slight analgetic activity was found in any of these compounds. The importance of nitrogen to aromatic ring distance for the analgetic-receptor interaction is discussed.


Asunto(s)
Analgésicos/síntesis química , Benzomorfanos/síntesis química , Morfinanos/síntesis química , Animales , Benzomorfanos/análogos & derivados , Benzomorfanos/farmacología , Fenómenos Químicos , Química , Masculino , Ratones , Relación Estructura-Actividad
13.
J Med Chem ; 18(12): 1266-7, 1975 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1195282

RESUMEN

10-Methoxy- (10) and 10-hydroxy-3-methyl-2,3,4,5,6,7-hexahydro-1H-3-benzazonine (11) have been synthesized from 7-methoxy-alpha-tetralone (1) via the 1-aminomethyl compound 4, which was converted to the amino acid derivative 7. Hydrogenation and cyclization of 7 afforded the lactam 9, which was reduced with LiAlH4, followed by N-methylation to give 10, from which 11 was obtained. Compounds 10 and 11 have analgetic activity, and the former was found to be comparable to codeine.


Asunto(s)
Analgésicos/síntesis química , Azepinas/síntesis química , Naftalenos/síntesis química , Analgésicos/farmacología , Animales , Azepinas/farmacología , Espectroscopía de Resonancia Magnética , Masculino , Ratones , Ratones Endogámicos , Naftalenos/farmacología , Presión , Tiempo de Reacción/efectos de los fármacos
14.
J Med Chem ; 22(12): 1558-60, 1979 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-119855

RESUMEN

Racemic 1,4-dimethyl- (1), 1,4,12 alpha-trimethyl- (2), and 1,4,12 beta-trimethyl-10-hydroxy-2,3,4,5,6,7-hexahydro-1,6-methano-1H-4-benzazonine (3) have been optically resolved. The analgesic potency and physical-dependence capacity of the optical isomers and their racemic parents were determined. The levo isomers of compounds 2 and 3 were analgesically much more potent than the dextro isomers and were equipotent with morphine. Optical resolution gave no effect on the activity of compound 1. None of the optical isomers and the racemates suppressed the morphine-withdrawal syndrome in the monkey.


Asunto(s)
Benzomorfanos/aislamiento & purificación , Morfinanos/aislamiento & purificación , Analgésicos , Animales , Benzomorfanos/análogos & derivados , Benzomorfanos/farmacología , Benzomorfanos/toxicidad , Haplorrinos , Humanos , Macaca mulatta , Ratones , Autoadministración , Estereoisomerismo , Relación Estructura-Actividad , Síndrome de Abstinencia a Sustancias/fisiopatología , Trastornos Relacionados con Sustancias/etiología
15.
J Med Chem ; 32(1): 256-64, 1989 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2909739

RESUMEN

The development of a prostaglandin PGF2 alpha photoaffinity probe led to the synthesis and biological evaluation of azide-substituted 17-phenyl-18,19,20-trinorprostaglandin F2 alpha and 16-phenoxy-17,18,19,20-tetranorprostaglandin F2 alpha derivatives. Two approaches for the preparation of iodinated versions of these prostaglandins were evaluated: (1) iodination of a phenyl azide bearing an activating hydroxyl group and (2) iodination of an aniline precursor to the phenyl azide group and subsequent conversion of the aniline to the phenyl azide. In the first approach, 17-(4-azido-2-hydroxyphenyl)-18,19,20-trinorprostaglandin F2 alpha, 16-(5-azido-3-hydroxyphenoxy)-17,18,19,20-tetranorprostaglandin F2 alpha, and 16-(4-azido-2-hydroxyphenoxy)-17,18,19,20-tetranorprostaglandin F2 alpha were prepared by using the Corey synthesis, but were biologically inactive presumably as a result of the hydrophilic phenolic hydroxyl group. In the second approach, the iodination of a 17-(4-aminophenyl)-18,19,20-trinorprostaglandin F2 alpha derivative delivered 17-(4-azido-3-iodophenyl)-18,19,20-trinorprostaglandin F2 alpha, which exhibited competitive binding with natural [3H]PGF2 alpha to ovine luteal cells and to plasma membranes of bovine corpora lutea. [125I]-17-(4-Azido-3-iodophenyl)-18,19,20-trinorprostaglandin F2 alpha was utilized in a preliminary photoaffinity cross-linking experiment.


Asunto(s)
Marcadores de Afinidad/síntesis química , Azidas/síntesis química , Prostaglandinas F Sintéticas/síntesis química , Animales , Azidas/metabolismo , Unión Competitiva , Membrana Celular/metabolismo , Fenómenos Químicos , Química , Femenino , Técnicas In Vitro , Prostaglandinas F Sintéticas/metabolismo , Receptores de Prostaglandina/metabolismo , Ovinos , Relación Estructura-Actividad
16.
J Endocrinol ; 148(2): 257-65, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8699140

RESUMEN

We examined vitamin A-deficient chicks to determine whether vitamin A affects the estrogen-induced development of the chick oviduct. When oviduct development was stimulated for 5 days with the synthetic estrogen, diethylstilbestrol, the wet weight of the oviduct in vitamin A-deficient chicks was only half that in control chicks. The DNA content in this tissue showed that the decreased oviduct weight in the vitamin A-deficient chicks was caused by the decreased proliferation of oviduct cells. However, the estrogen-induced expression of the ovalbumin gene was not affected by the vitamin A deficiency, suggesting that estrogen-induced cytodifferentiation is not affected by vitamin A. To clarify the vitamin A action on estrogen-induced development in the oviduct, transcripts of nuclear estrogen receptor (ER) and all-trans-retinoic acid (RAR alpha, beta and gamma) receptors, which exert the effects of estrogen and vitamin A, were measured. The ER, RAR alpha and RAR beta genes, but not that of RAR gamma, were expressed during oviduct development, indicating that estrogen and vitamin A may control the expression of target genes through their cognate receptors. Thus, we have shown that vitamin A is involved in estrogen-induced cell proliferation but not in cytodifferentiation of the chicken oviduct.


Asunto(s)
Dietilestilbestrol/farmacología , Oviductos/citología , Vitamina A/fisiología , Animales , Northern Blotting , Diferenciación Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Pollos , Femenino , Expresión Génica , Tamaño de los Órganos/efectos de los fármacos , Oviductos/efectos de los fármacos , Oviductos/metabolismo , Receptores de Estrógenos/genética , Receptores de Ácido Retinoico/genética , Deficiencia de Vitamina A/patología
17.
Artículo en Inglés | MEDLINE | ID: mdl-2762366

RESUMEN

The ionophoretic activity of PGBx, an oligomeric mixture synthesized from 15-dehydro PGB1, with different cations was measured using arsenazo III-entrapped liposomes. The order of ionophoretic activity was Zn2+ greater than Co2+ greater than Mn2+ greater than Cu2+ greater than Ca2+ greater than Ba2+ greater than Sr2+ greater than Mg2+. The intrinsic fluorescence of PGBx was quenched by the binding of divalent cations as well as by La3+ and H+. Quenching by K+ and Na+ was minimal. The order of quenching strength of divalent cations was Zn2+ greater than Co2+ greater than Cu2+ = Mn2+ greater than Ca2+ greater than Ba2+ greater than Sr2+ greater than Mg2+. Binding affinities of these cations determined by a murexide indicator method were in good agreement with that determined by the fluorescence quenching reaction. The cation binding affinity of PGBx in aqueous solutions correlates with the ionophoretic activity in liposomes. The binding affinity for K+ was estimated from the inhibition by K+ of Ca2+ binding by PGBx. Although PGBx has a lower selectivity for divalent cation binding than the ionophore A23187, the characteristics of the binding affinity of these two compounds for various ions were similar. The pK of PGBx as determined by fluorescence quenching was 6.7. The molecular weight of the divalent cation binding unit was estimated to be about 680, with each PGBx molecule having three such binding sites. The binding of Ca2+ to such a site is one-to-one.


Asunto(s)
Cationes Bivalentes/metabolismo , Ionóforos , Polímeros/farmacología , Prostaglandinas B/farmacología , Prostaglandinas Sintéticas/farmacología , Prostaglandinas/farmacología , Animales , Indicadores y Reactivos , Cinética , Liposomas , Naftalenosulfonatos , Espectrometría de Fluorescencia
18.
J Biosci Bioeng ; 91(5): 525-7, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-16233034

RESUMEN

The enantiomeric excess (ee) of (S)-1,2-propanediol produced by baker's yeast-mediated reduction of 1-acetoxy-2-propanone was improved to 96% ee by a fed-batch operation of the substrate. A similar reduction of 1-benzoyloxy-2-propanone stopped because of the inhibition toward the enzymes for NADPH regeneration by the reduction product. The inhibition was prevented using resin that adsorbs the product from the reaction mixture, and 70 g/l substrate was reduced yielding (S)-1-benzoyloxy-2-propanol at > 99% ee.

19.
Yakugaku Zasshi ; 115(8): 626-32, 1995 Aug.
Artículo en Japonés | MEDLINE | ID: mdl-7473060

RESUMEN

Inhibitory effects of hydroquinone-alpha-glucoside (HQ-alpha-G) on the melanogenesis were investigated and compared with those of arbutin. The levels of inhibitory effects of HQ-alpha-G and arbutin on the tyrosinase activity were nearly the same. Inhibitory effects of both compounds on the melanogenesis, were studied using cultured B16 melanoma cells, and HQ-alpha-G was also found to have a similar effect to that of arbutin without inhibiting cell growth. In this experiment, while HQ-alpha-G hardly inhibited cell growth at 1 mM, arbutin inhibit it significantly at the same concentration. From these results it is suggested that HQ-alpha-G as well as arbutin inhibited the melanogenesis by affecting tyrosinase rather than by killing melanocytes. Furthermore, the melanogenesis of guinea-pigs with brown hair was reduced to about 80% by applying them each compound. The great differences in toxicity to normal human keratinocyte were not recognized between these two glucosides. It is, therefore, considered that HQ-alpha-G is an effective and safe ingredient for cosmetics.


Asunto(s)
Glucósidos/farmacología , Melaninas/biosíntesis , Melanoma Experimental/metabolismo , Animales , Arbutina/farmacología , División Celular/efectos de los fármacos , Glucósidos/toxicidad , Cobayas , Humanos , Queratinocitos/efectos de los fármacos , Masculino , Melanocitos/efectos de los fármacos , Melanoma Experimental/patología , Monofenol Monooxigenasa/metabolismo , Células Tumorales Cultivadas
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