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1.
Int J Oral Maxillofac Surg ; 49(4): 515-521, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31500953

RESUMEN

Oral cancer screening is important for early detection and early treatment, which help improve survival rates. Biopsy is invasive and painful, while fluorescence visualization using optical instruments is non-invasive, convenient, and provides results in real time, and examinations can be repeated. The purpose of this study was to determine the usefulness of optical instruments in oral screening. A total of 314 patients who were examined using optical instruments at Tokyo Dental College between 2014 and 2018 were enrolled in this study. Fluorescence visualization images were analyzed using subjective and objective evaluations. Subjective evaluation for detecting oral cancer offered 98.0% sensitivity and 43.2% specificity. Regarding the objective evaluations for detecting oral cancer, sensitivity and specificity were 61.9% and 62.7% for mean luminance, 90.3% and 55.7% for luminance ratio, 56.5% and 67.7% for standard deviation of luminance, and 72.5% and 85.4% for coefficient of variation of luminance. Fluorescence visualization with subjective and objective evaluation using optical instruments is useful for oral cancer screening.


Asunto(s)
Neoplasias de la Boca , Lesiones Precancerosas , Biopsia , Detección Precoz del Cáncer , Humanos , Sensibilidad y Especificidad
2.
Br J Pharmacol ; 164(1): 181-91, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21410690

RESUMEN

BACKGROUND AND PURPOSE: The renal sodium-glucose cotransporter 2 (SGLT2) plays an important role in the reuptake of filtered glucose in the proximal tubule and therefore may be an attractive target for the treatment of diabetes mellitus. This study characterizes the pharmacological profile of TS-071 ((1S)-1,5-anhydro-1-[5-(4-ethoxybenzyl)-2-methoxy-4-methylphenyl]-1-thio-D-glucitol hydrate), a novel SGLT2 inhibitor in vitro and in vivo. EXPERIMENTAL APPROACH: Inhibition of glucose uptake by TS-071 was studied in CHO-K1 cells stably expressing either human SGLT1 or SGLT2. Single oral dosing studies were performed in rats, mice and dogs to assess the abilities of TS-071 to increase urinary glucose excretion and to lower plasma glucose levels. KEY RESULTS: TS-071 inhibited SGLT2 activity in a concentration-dependent manner and was a potent and highly selective inhibitor of SGLT2. Orally administered TS-071 increased urinary glucose excretion in Zucker fatty rats and beagle dogs at doses of 0.3 and 0.03 mg·kg(-1) respectively. TS-071 improved glucose tolerance in Zucker fatty rats without stimulating insulin secretion and reduced hyperglycaemia in streptozotocin (STZ)-induced diabetic rats and db/db mice at a dose of 0.3 mg·kg(-1). CONCLUSION AND IMPLICATIONS: These data indicate that TS-071 is a potent and selective SGLT2 inhibitor that improves glucose levels in rodent models of type 1 and 2 diabetes and may be useful for the treatment for diabetes mellitus.


Asunto(s)
Hiperglucemia/tratamiento farmacológico , Hipoglucemiantes/farmacología , Riñón/efectos de los fármacos , Riñón/metabolismo , Inhibidores del Cotransportador de Sodio-Glucosa 2 , Sorbitol/análogos & derivados , Animales , Glucemia/metabolismo , Células CHO , Cricetinae , Cricetulus , Desoxiglucosa/metabolismo , Diabetes Mellitus/tratamiento farmacológico , Diabetes Mellitus/metabolismo , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Experimental/metabolismo , Perros , Glucosuria/tratamiento farmacológico , Glucosuria/metabolismo , Humanos , Hiperglucemia/sangre , Hiperglucemia/metabolismo , Hipoglucemiantes/farmacocinética , Insulina/metabolismo , Secreción de Insulina , Masculino , Ratones , Ratones Endogámicos C57BL , Ratas , Ratas Sprague-Dawley , Ratas Zucker , Transportador 1 de Sodio-Glucosa/metabolismo , Transportador 2 de Sodio-Glucosa/metabolismo , Sorbitol/farmacocinética , Sorbitol/farmacología
3.
Calcif Tissue Int ; 70(6): 488-95, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12016462

RESUMEN

26,27-hexafluoro-1a,25-dihydroxyvitamin D3 (F6-D3) has been reported to be 5-10 times more potent than 1a,25-dihydroxyvitamin D3[1,25(OH)2D3] in biological systems in vivo and in vitro. However, the effect of F6-D3 on bone formation has yet to be clarified. In the present study, we investigated the effect of F6-D3 on SV40-transfected human fetal osteoblastic cells (SV-HFO) and found it to be about 100 times greater than that of 1,25(OH)2D3 in stimulating calcification. F6-D3 was also about 100 times more effective than 1,25(OH)2D3 in enhancing the expression of mRNA for alkaline phosphatase (ALP), osteocalcin (OCN), and osteopontin (OPN). In the presence of 10?8 M F6-D3 and 10?6 M 1,25(OH)2D3, the calcification began on day 9 and increased up to day 19. Expression of mRNA for ALP and OCN reached a maximum on day 4 and thereafter declined. On the other hand, when osteoblastic cells were incubated with a low level of [1b-3H]-F6-D3- or [1b-3H]-1,25(OH)2D3, each radioactive peak could not be detected. However, on the incubation of osteoblastic cells and radioactive substrate in the presence of ketoconazole, a selective inhibitor of CYP24, a clear peak for each substrate was detected. This suggested that F6-D3 as well as 1,25(OH)2D3 is metabolized by CYP24. Osteoblastic cells were incubated with 10?8 M[1b-3H]-F6-D3 or 10?8 M[1b-3H]-1,25(OH)2D3 for 4, 9, and 14 days. A small peak of 1,25(OH)2D3 was observed and thereafter its level decreased. In addition, two unknown peaks increased when the culture period was extended. In the case of F6-D3, peaks of F6-D3 and 26,27-hexafluoro-23-oxo-1a,25(OH)2D3(23-oxo-F6) were clearly detected, the latter being about 4 times higher than the former. Both peaks was retained up to day 14. The amount of unlabeled F6-D3 and 23-oxo-F6 calculated from the specific radioactivity in the cells may be similar to the amount of 1,25(OH)2D3 and its metabolites. The strong activity of F6-D3 in stimulating calcification may be due to the fact that F6-D3 is much more potent than 1,25(OH)2D3 in enhancing the expression of mRNA for ALP, OCN, and OPN and that the amount of F6-D3 and 23-oxo-F6 accumulated in the cells is much greater than that of 1,25(OH)2D3 and its metabolite.


Asunto(s)
Calcificación Fisiológica/efectos de los fármacos , Calcitriol/análogos & derivados , Calcitriol/farmacología , Osteoblastos/efectos de los fármacos , Fosfatasa Alcalina/genética , Fosfatasa Alcalina/metabolismo , Northern Blotting , Línea Celular Transformada , Transformación Celular Viral , Relación Dosis-Respuesta a Droga , Feto , Humanos , Hidroxiprolina/metabolismo , Osteoblastos/metabolismo , Osteocalcina/genética , Osteocalcina/metabolismo , Osteopontina , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sialoglicoproteínas/biosíntesis , Sialoglicoproteínas/genética , Coloración y Etiquetado
4.
Xenobiotica ; 30(11): 1055-62, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11197067

RESUMEN

1. To clarify the possibility that the metabolism of 26,27-hexafluoro-1 alpha,25-dihydroxyvitamin D3 [F6-1,25(OH)2D3] to 26,27-hexafluoro-1 alpha,23(S),25-trihydroxyvitamin D3 [F6-1,23,25(OH)3D3 and that of F6-1,23,25(OH)3D3 to 26,27-hexafluoro-23-oxo-1 alpha,25-dihydroxyvitamin D3 [F6-23-oxo-1,25(OH)2D3] are catalysed by 25-hydroxyvitamin D3 24-hydroxylase (CYP24), ROS17/2.8 cells transfected with a plasmid expressing CYP24 [pSVL-CYP24(+)] and a corresponding blank plasmid [pSLV-CYP24R(-)] were used. 2. Incubation of [1 beta-3H]-F6-1,25(OH)2D3 for 2 and 5 days with ROS17/2.8 cells transfected with pSVL-CYP24(+) generated a metabolite that co-migrated with authentic F6-1,23,25(OH)3D3 in both normal phase and reversed-phase HPLC systems. 3. Incubation of [1 beta-3H]-F6-1,23,25(OH)3D3 for 5 days with pSVL-CYP24(+)- transfected ROS 17/2.8 cells generated a metabolite that co-migrated with authentic F6-23-oxo-1,25(OH)2D3. In contrast, the metabolites F6-1,23,25(OH)3D3 or F6-23-oxo-1,25(OH)2D3 were not generated in the cells transfected with pSVL-CYP24R(-). 4. The results indicate that CYP24 catalyses the conversion of F6-1,25(OH)2D3 to F6-1,23,25(OH)3D3 and that of F6-1,23,25(OH)3D3 to F6-23-oxo-1,25(OH)2D3.


Asunto(s)
Calcitriol/análogos & derivados , Calcitriol/metabolismo , Sistema Enzimático del Citocromo P-450/biosíntesis , Sistema Enzimático del Citocromo P-450/fisiología , Esteroide Hidroxilasas/biosíntesis , Esteroide Hidroxilasas/fisiología , Animales , Línea Celular , Cromatografía Líquida de Alta Presión , Modelos Químicos , Osteoblastos/metabolismo , Plásmidos/metabolismo , Ratas , Factores de Tiempo , Transfección , Células Tumorales Cultivadas , Vitamina D3 24-Hidroxilasa
5.
J Nutr Sci Vitaminol (Tokyo) ; 45(3): 239-49, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10524344

RESUMEN

26,27-Hexafluoro-1 alpha,25-dihydroxyvitamin D3 [F6-1,25-(OH)2D3] is more potent than 1 alpha,25-dihydroxyvitamin D3 [1,25(OH)2D3] in stimulating bone resorption in vitro and in vivo. The reason why F6-1,25(OH)2D3 is more active remains unclear. To clarify the relationship between the bone-resorbing activity of each vitamin D3 analogue and the metabolism of each analogue, in the present study, we used an ex vivo method that was established by Reynolds et al (Calcif Tissue Res, 1974, 15, 333-339). The effect of F6-1,25(OH)2D3 or 1,25(OH)2D3 on 45Ca release from parietal bones, prepared at 3, 14 and 24 h after injection of 1.9, 3.8, 7.6 or 15.2 pmol vitamin D analog/g body weight, was examined. F6-1,25(OH)2D3 was more potent than 1,25(OH)2D3 during each in vivo time period. 1,25(OH)2D3 at 3 h after the injection was more active compared to the control (no injection of 1,25(OH)2D3) but not at 14 and 24 h. The radioactivity of the bones after the injection of [3H]-F6-1,25(OH)2D3 was retained even at 24 h. In the case of [3H]-1,25(OH)2D3, the radioactivity of bones decreased with an increase in the in vivo period. In a HPLC analysis of the lipid extract of bone homogenate, [3H]-F6-1,25(OH)2D3 alone was detected at 3 h after the injection and both [3H]-F6-1,25(OH)2D3 and [3H]-26,27-hexafluoro-1 alpha, 23S,25-trihydroxyvitamin D3 [F6-1,23,25(OH)3D3] were detected at 14 and 24 h after the injection. [3H]-1,25(OH)2D3 was highly detected at 3 h after the injection, but it decreased with an increase in the in vivo period. In the ex vivo test, the activity of F6-1,23,25(OH)3D3 was less than that of F6-1,25(OH)2D3 but similar to that of 1,25(OH)2D3. The present study indicates that F6-1,25(OH)2D3 is more active and more long-lasting than 1,25(OH)2D3 in the ex vivo method. A higher potency of F6-1,25(OH)2D3 is explained, at least partly, by the results that the amounts of both F6-1,25(OH)2D3 and its active metabolite, F6-1,23,25(OH)3D3, in the bones are higher than that of 1,25(OH)2D3, and that F6-1,25(OH)2D3 and its metabolite are retained in bones longer than 1,25(OH)2D3.


Asunto(s)
Resorción Ósea , Calcitriol/análogos & derivados , Calcitriol/farmacología , Animales , Animales Recién Nacidos/metabolismo , Huesos/efectos de los fármacos , Huesos/metabolismo , Calcitriol/administración & dosificación , Calcitriol/farmacocinética , Radioisótopos de Calcio/metabolismo , Cromatografía Líquida de Alta Presión , Cinética , Ratones , Tritio
6.
Calcif Tissue Int ; 56(3): 220-6, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7750028

RESUMEN

Five analogs of 1 alpha,25-dihydroxyvitamin D3 [1,25(OH)2D3] [1], 26,27-dimethyl-1 alpha,25-dihydroxyvitamin D3 [1,25(OH)2(Me)2D3] [2], 26,27-dimethyl-1 alpha,25-dihydroxyvitamin D3 [1,25(OH)2(Et)2D3] [3], 26,27-dipropyl-1 alpha,25-dihydroxyvitamin D3 [1,25(OH)2(Pr)2D3] [4], 26,27-dimethyl-24,24-difluoro-1 alpha,25-dihydroxyvitamin D3 [24F2-1,25(OH)2(Me)2D3], and [5] 24a-homo-24,24-difluoro-1 alpha,25- dihydroxyvitamin D3 [24aF2-homo-1,25(OH)2D3] were investigated to clarify the possibility that prevents osteopenia induced in rats by ovariectomy and sciatic neurotomy. The objective of our studies was to determine whether these analogs may be effective for treatment of subjects with osteoporosis. 1,25(OH)2(Me)2D3, 24F2-1,25(OH)2(Me)2D3, and 24aF2-homo-1,25(OH)2D3 prevented decreases in bone mineral density (BMD) of the femur, as measured by dual energy X-ray absorptiometry (DXA). The potency of 1,25(OH)2(Me)2D3 in this test was higher than that of 1,25(OH)2D3. The potencies of 24F2-1,25(OH)2(Me)2D3 and 24aF2-homo-1,25(OH)2D3 were similar to that of 1,25(OH)2D3. On the other hand, though 1,25(OH)2(Et)2D3 and 1,25(OH)2(Pr)2D3 had a preventive effect on the decrease in BMD, the potency of two analogs was lower than that of 1,25(OH)2D3. Decreases in cortical and trabecular bone areas of the femur were prevented by three analogs of 1,25(OH)2D3, 1,25(OH)2(Me)2D3, 24F2-1,25(OH)2(Me)2D3, and 24aF2-homo-1,25(OH)2D3. Serum calcium (Ca) concentration was elevated at the last administration of three analogs of 1,25(OH)2D3, 1,25(OH)2(Me)2D3, 24F2-1,25(OH)2-(Me)2D3 and 24aF2-homo-1,25(OH)2D3.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Densidad Ósea/efectos de los fármacos , Enfermedades Óseas Metabólicas/prevención & control , Calcitriol/química , Osteoporosis Posmenopáusica/prevención & control , Absorciometría de Fotón , Análisis de Varianza , Animales , Peso Corporal/efectos de los fármacos , Calcitriol/análogos & derivados , Calcitriol/uso terapéutico , Calcio/sangre , Modelos Animales de Enfermedad , Femenino , Fémur/efectos de los fármacos , Fémur/fisiología , Humanos , Ovariectomía/efectos adversos , Ratas , Ratas Wistar , Relación Estructura-Actividad
7.
J Biol Chem ; 269(51): 32418-25, 1994 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-7528216

RESUMEN

The alpha-series ganglioside, IV3NeuAc,III6NeuAcGgOse4-Cer(GD1 alpha), was previously identified as a minor constituent in bovine brain gangliosides (Hirabayashi, Y., Hyogo, A., Nakao, T., Tsuchiya, K., Suzuki, Y., Matsumoto, M., Kon, K, and Ando, S. (1990) J. Biol. Chem. 265, 8144-8151). In the present study, we have generated a specific mouse monoclonal antibody against GD1 alpha and explored the distribution of GD1 alpha in murine central nervous system. In adult rat brain, GD1 alpha occurred as a minor constituent, and its expression was exclusively detected in the forebrain, the midbrain and the cerebellum. In the mouse cerebellum, the content of GD1 alpha was reduced significantly in the Purkinje cell-deficient mutants, lurcher (Lc/+), staggerer (sg/sg), and Purkinje cell degeneration (pcd/pcd), but were not reduced in the weaver (wv/wv) mutant, which loses mostly granule cells. The GD1 alpha synthase, assayed in cerebellar microsomes, was also reduced in Purkinje cell-deficient mutants. Immunohistochemistry showed that the staining for GD1 alpha in rat and mouse cerebella was mostly found in the proximal dendrites and cell bodies of Purkinje cells. Also, it appeared slightly in the processes of Bergmann glial cells. The immunoreactivity of GD1 alpha disappeared specifically from the Purkinje cell dendrites and the Bergmann glial processes after co-application of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) and 8-bromo-guanosine 3':5'-cyclic monophosphate, which induced long-term desensitization of the AMPA-selective glutamate receptors in Purkinje cells. The present data provide suggestive evidence that GD1 alpha ganglioside is enriched in Purkinje cells and may have a role in Purkinje cell functions in the cerebellum.


Asunto(s)
Gangliósido G(M1)/análogos & derivados , Células de Purkinje/metabolismo , Animales , Anticuerpos Monoclonales/inmunología , Especificidad de Anticuerpos , Secuencia de Carbohidratos , Bovinos , GMP Cíclico/análogos & derivados , GMP Cíclico/farmacología , Gangliósido G(M1)/biosíntesis , Gangliósido G(M1)/inmunología , Humanos , Inmunohistoquímica , Masculino , Ratones , Datos de Secuencia Molecular , Mutación , Células de Purkinje/efectos de los fármacos , Ratas , Ratas Wistar , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiónico/farmacología
8.
Res Commun Mol Pathol Pharmacol ; 86(2): 183-93, 1994 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7881867

RESUMEN

We investigated the metabolism of 26,26,26,27,27,27-hexafluoro-1 alpha,25-dihydroxyvitamin D3 (26,27-F6-1,25(OH)2D3, ST-630) and 1 alpha,25-dihydroxyvitamin (1,25(OH)2D3) in cultured neonatal mouse calvaria to elucidate why ST-630 is more potent than 1,25(OH)2D3 in stimulating bone resorption in organ culture. The metabolites were extracted with ethyl acetate or chloroform/methanol (1:1) from cultured calvaria or medium incubated with [3H]-ST-630 or [3H]-1,25(OH)2D3 for various periods, and separated by high performance liquid chromatography. [3H]-ST-630 in cultured calvaria was converted to [3H]-26,26,26,27,27,27-hexafluoro-1 alpha,23(S),25-trihydroxyvitamin D3(26,27-F6-1,23,25(OH)3D3,ST-232), which stimulated bone resorption equipotently as 1,25(OH)2D3. The amount of [3H]-ST-232 produced in the bone increased with passage of the culture period. In contrast, the amount of [3H]-ST-630 in the bones decreased in the 2 day cultures. In the medium, [3H]-ST-630 was hardly detectable for 2 days. This suggests that ST-630 is metabolized to ST-232 which is retained in the bones. On the other hand, some [3H]-1,25(OH)2D3 was metabolized to inactive forms detectable in the medium. Therefore, the high potency of ST-630 in stimulating bone resorption in organ culture may be associated with a difference between ST-630 and 1,25(OH)2D3 in the mode of metabolism in the cultured bones.


Asunto(s)
Calcitriol/análogos & derivados , Calcitriol/metabolismo , Cráneo/metabolismo , Animales , Animales Recién Nacidos , Resorción Ósea/metabolismo , Cromatografía Líquida de Alta Presión , Medios de Cultivo , Ratones , Técnicas de Cultivo de Órganos
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