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5.
J Fish Biol ; 77(6): 1325-42, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21039508

RESUMEN

Variations in otolith patterns, sizes and body morphometrics of jack mackerel Trachurus japonicus juveniles were investigated. Under transmitted light, translucent (W(t)) and opaque otoliths (W(o)) were detected in juveniles collected from Wakasa Bay between July 2005 and April 2006, whereas only opaque otoliths (G(o)) were detected in Goto-nada Sea individuals between May and June 2006. Three groups of juveniles were distinguished based on differences in hatch season, otolith size and growth history, and body morphometrics. As T. japonicus has different spawning seasons according to spawning grounds, each group was estimated to hatch in different waters. Juveniles with W(t) otoliths were considered to have stayed in coastal habitat longer, as the hatch area was estimated to be near Wakasa Bay. Juveniles with W(o) and G(o) otoliths appear to recruit to coastal waters at larger size, since their hatch areas were estimated to be far from each collection area. Larger otoliths of W(t) were attributed to otolith accretion after the second growth flexion, which was observed only for W(t) . Standard length of W(t) fish at the second otolith growth flexion was estimated to correspond to recruitment size to coastal rocky reefs in Wakasa Bay. Body morphometrics were correlated with otolith size after removing body size effect, suggesting that morphological variations of T. japonicus juveniles were also associated with the timing of recruitment to coastal habitat.


Asunto(s)
Membrana Otolítica/crecimiento & desarrollo , Perciformes/crecimiento & desarrollo , Animales , Tamaño Corporal , Ecosistema , Japón , Membrana Otolítica/anatomía & histología , Perciformes/anatomía & histología , Estaciones del Año
6.
Water Sci Technol ; 62(1): 85-91, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20595757

RESUMEN

The mutagens produced through chemical reaction between chlorine and the insecticide fenitrothion were studied by using a quadrupole GC-MS. The mutagenicity and the mutagen formation potential (MFP) of the identified by-products were evaluated by the Ames assay (preincubation method) using Salmonella typhimurium TA100 without exogenous activation by S9 mix (TA100-S9). Before conducting GC/MS analyses, six compounds were presumed to be produced in chlorinated fenitrothion. These compounds were confirmed to be produced by the GC/MS analyses, but none of them were mutagenic. One of the chlorination by-products, 3-methyl-4-nitrophenol, has 19 times greater MFP than that of fenitrothion. This result suggests that a major mutagen in chlorinated fenitrothion will be produced via a chemical reaction between chlorine and 3-methyl-4-nitrophenol.


Asunto(s)
Fenitrotión/química , Halogenación , Insecticidas/química , Mutágenos/química , Cromatografía de Gases y Espectrometría de Masas , Pruebas de Mutagenicidad
7.
Rev Sci Instrum ; 78(1): 013703, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17503924

RESUMEN

We have established a fabrication process for conductive carbon nanotube (CNT) tips for multiprobe scanning tunneling microscope (STM) with high yield. This was achieved, first, by attaching a CNT at the apex of a supporting W tip by a dielectrophoresis method, second, by reinforcing the adhesion between the CNT and the W tip by electron beam deposition of hydrocarbon and subsequent heating, and finally by wholly coating it with a thin metal layer by pulsed laser deposition. More than 90% of the CNT tips survived after long-distance transportation in air, indicating the practical durability of the CNT tips. The shape of the CNT tip did not change even after making contact with another metal tip more than 100 times repeatedly, which evidenced its mechanical robustness. We exploited the CNT tips for the electronic transport measurement by a four-terminal method in a multiprobe STM, in which the PtIr-coated CNT portion of the tip exhibited diffusive transport with a low resistivity of 1.8 kOmega/microm. The contact resistance at the junction between the CNT and the supporting W tip was estimated to be less than 0.7 kOmega. We confirmed that the PtIr thin layer remained at the CNT-W junction portion after excess current passed through, although the PtIr layer was peeled off on the CNT to aggregate into particles, which was likely due to electromigration or a thermally activated diffusion process. These results indicate that the CNT tips fabricated by our recipe possess high reliability and reproducibility sufficient for multiprobe STM measurements.


Asunto(s)
Conductividad Eléctrica , Microscopía de Túnel de Rastreo , Nanotubos de Carbono , Microscopía de Túnel de Rastreo/instrumentación , Microscopía de Túnel de Rastreo/métodos , Nanotubos de Carbono/ultraestructura
8.
J Periodontal Res ; 42(1): 90-5, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17214645

RESUMEN

BACKGROUND AND OBJECTIVE: This study compared the effectiveness of two piezoelectric ultrasonic scalers and a hand scaler for subgingival scaling and root planing in vivo. MATERIAL AND METHODS: Fifteen patients with advanced periodontal disease and with teeth scheduled for extraction were selected for this study. Three experimental groups of 10 teeth each were treated with one of two piezoelectric ultrasonic scalers [Vector scaler and Enac scaler] or with a hand scaler. Instrumentation was continued until the root surface felt hard and smooth to an explorer tip. The root surface characteristics after instrumentation were examined using scanning electron microscopy, and the amount of remaining calculus, roughness and loss of tooth substance were estimated using the remaining calculus index and roughness loss of tooth substance index. RESULTS: The remaining calculus index did not differ significantly among the three groups. The roughness loss of tooth substance index was significantly lower for the Vector scaler and Enac scaler groups than for the hand scaler group and also differed significantly between the Vector scaler and Enac scaler groups. CONCLUSION: This study suggests that the Vector scaler produces a smooth root surface with minimal loss of tooth substance. It is a reasonable choice for gentle periodontal maintenance treatment.


Asunto(s)
Raspado Dental/instrumentación , Raíz del Diente/ultraestructura , Terapia por Ultrasonido/instrumentación , Cálculos Dentales/terapia , Cálculos Dentales/ultraestructura , Cemento Dental/ultraestructura , Humanos , Microscopía Electrónica de Rastreo , Enfermedades Periodontales/terapia , Aplanamiento de la Raíz/instrumentación , Cuello del Diente/ultraestructura
9.
Aquat Toxicol ; 79(4): 376-83, 2006 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-16930737

RESUMEN

To investigate the effect of estrogenic compounds on the marine mussel Mytilus edulis, an assay was developed to measure the expression of two vertebrate estrogen responsive genes-estrogen receptor (ER) and vitellogenin (VTG) genes. Expression was measured in M. edulis gonads following a 10-day exposure to 200 ng/l 17beta-estradiol (estradiol). The concentrations of esterified estradiol in mussel tissue increased 15-fold in a time-dependent manner-confirming uptake of the compound by the mussels, however there was no significant increase of free estradiol in mussel tissues during the exposure period. The ER and VTG mRNA levels in the gonads of both sexes were measured at days 1-3, 5, and 10 in control and exposed mussels. However, no significant change in the expression of either the ER or VTG genes was recorded at any of the sampled time points. The results suggest that either a regulatory mechanism exists in a mussel that is able to maintain constant levels of free estradiol by converting the excess estradiol into esterified products which may have reduced affinity for the estrogen receptor, or alternatively, that the ER and VTG genes are unresponsive to estrogens in these organisms. The significance of these findings in terms of the utility of ER and VTG as biomarkers of endocrine disruption in bivalve species is discussed.


Asunto(s)
Estradiol/toxicidad , Expresión Génica/efectos de los fármacos , Mytilus edulis/efectos de los fármacos , Receptores de Estrógenos/genética , Vitelogeninas/genética , Contaminantes Químicos del Agua/toxicidad , Secuencia de Aminoácidos , Animales , Cartilla de ADN/química , Estradiol/análisis , Femenino , Gónadas/química , Gónadas/efectos de los fármacos , Masculino , Datos de Secuencia Molecular , Mytilus edulis/química , ARN Mensajero/análisis , Receptores de Estrógenos/biosíntesis , Receptores de Estrógenos/efectos de los fármacos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/veterinaria , Alineación de Secuencia/veterinaria , Vitelogeninas/biosíntesis , Vitelogeninas/efectos de los fármacos , Agua/análisis
10.
Exp Clin Endocrinol Diabetes ; 113(7): 365-71, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16025396

RESUMEN

We examined the effect of PGE1 on the expression of plasminogen activator inhibitor-1 (PAI-1) mRNA induced by tumor necrosis factor-alpha (TNF-alpha) in human mesangial cells, because PAI-1 is one of major factors for the progression of glomerulosclerosis. The expression of PAI-1 mRNA was increased after stimulation with TNF-alpha, and it was diminished by pre-incubation with PGE1. Next, we examined the effect of PGE1 on the phosphorylation of mitogen activated protein kinase (MAPK) family and Akt. TNF-alpha activated the phosphorylation of p44/42 MAPK, p38 MAPK, SAPK/JNK and Akt in mesangial cells. PGE1 inhibited the TNF-alpha induced phosphorylation of SAPK/JNK and Akt, but not p44/42 MAPK and p38 MAPK. The TNF-alpha induced expression of PAI-1 mRNA was not affected by PD98059, an inhibitor of MEK, SB203580, an inhibitor of p38 MAPK, nor LY294002, an inhibitor of PI3 K. However, DMAP, an inhibitor of SAPK/JNK, inhibited the expression of PAI-1 mRNA, suggesting that the TNF-alpha induced expression of PAI-1 mRNA is regulated by the SAPK/JNK dependent pathway in human mesangial cells. By the incubation with H8, an inhibitor of PKA, the inhibitory effect of PGE1 on the expression of PAI-1 mRNA was abolished, suggesting that PGE1 inhibited the PAI-1 mRNA expression via the PKA pathway. Our results suggest that the inhibition of PAI-1 synthesis by PGE1 in human mesangial cells may have therapeutic implications for glomerulosclerosis such as occurs in diabetic nephropathy.


Asunto(s)
Alprostadil/farmacología , Nefropatías Diabéticas/inmunología , Mesangio Glomerular/efectos de los fármacos , Inhibidor 1 de Activador Plasminogénico/biosíntesis , Factor de Necrosis Tumoral alfa/farmacología , Northern Blotting , Western Blotting , AMP Cíclico/metabolismo , Interacciones Farmacológicas , Mesangio Glomerular/metabolismo , Humanos , Proteínas Quinasas Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Fosforilación , Inhibidor 1 de Activador Plasminogénico/genética , Inhibidores de Proteínas Quinasas/farmacología , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores
11.
J Endocrinol Invest ; 26(11): 1128-35, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15008254

RESUMEN

We report a 22-yr-old male patient with idiopathic hypothalamic hypogonadism who showed secondary resistance to gonadotropin (Gn) therapy over 3 yr after successful treatment with hCG combined with human menopausal Gn. The patient simultaneously developed subclinical hypothyroidism. Endocrine examination revealed low levels of testosterone (0.3 ng/ml), free T4 (0.91 ng/dl), and increased levels of TSH (31.1 microU/ml) in the serum. Serum autoantibodies to thyroid gland were all negative. Interestingly, thyroid function was improved after discontinuation of Gn therapy. In vitro assays by immunoprecipitation using 125I-hCG or 125I-TSH elucidated the presence of anti-hCG antibody in the serum 13 months after commencement of Gn therapy but anti-TSH antibody was not detected in the serum. Furthermore, the anti-hCG antibody specifically bound to hCG but not to other glycoproteins including TSH and FSH based on a competitive displacement assay. Bioassays using porcine thyroid cells revealed that the serum gamma-globulin fraction enables the suppression of cyclic AMP (cAMP) synthesis stimulated by TSH. Our findings suggest that anti-hCG and/or anti-idiotypic hCG antibodies induced by hCG therapy impaired TSH-dependent cAMP production through interfering with binding of TSH to its receptor, and this resulted in subclinical hypothyroidism in this patient.


Asunto(s)
Anticuerpos/sangre , Gonadotropina Coriónica/inmunología , Gonadotropina Coriónica/uso terapéutico , Hipogonadismo/complicaciones , Hipotiroidismo/complicaciones , Adulto , Anticuerpos/inmunología , Autoanticuerpos/sangre , Gonadotropina Coriónica/efectos adversos , AMP Cíclico/biosíntesis , Humanos , Hipogonadismo/tratamiento farmacológico , Hipogonadismo/inmunología , Hipogonadismo/metabolismo , Hipotiroidismo/inmunología , Hipotiroidismo/metabolismo , Masculino , Pruebas de Precipitina , Prolactina , Tirotropina/sangre
12.
Horm Metab Res ; 34(2): 49-54, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11972286

RESUMEN

It has been reported that alpha-tocopherol, an antioxidant agent, may play a role in preventing diabetic angiopathy. However, there is little evidence to show the effect of alpha-tocopherol on the production of pro-inflammatory cytokines in endothelial cells. Therefore, we examined the effect of alpha-tocopherol on the regulation of IL-8 synthesis induced by high glucose and/or thrombin in endothelial cells. Thrombin alone markedly increased the IL-8 release. Furthermore, high glucose levels and thrombin combined had additive effects on IL-8 synthesis, and alpha-tocopherol diminished their effect; alpha-tocopherol also inhibited the phosphorylation of IkappaB-alpha induced by high glucose levels and/or thrombin. Our results suggest that the administration of alpha-tocopherol to diabetic patients may have a beneficial effect for the prevention of diabetic vascular complications by the inhibition of IL-8 synthesis from endothelial cells.


Asunto(s)
Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/metabolismo , Glucosa/farmacología , Proteínas I-kappa B , Interleucina-8/biosíntesis , Trombina/farmacología , alfa-Tocoferol/farmacología , Aorta , Células Cultivadas , Proteínas de Unión al ADN/metabolismo , Interacciones Farmacológicas , Glucosa/administración & dosificación , Humanos , Interleucina-8/genética , Inhibidor NF-kappaB alfa , Fosforilación , ARN Mensajero/análisis , Transducción de Señal
13.
J Steroid Biochem Mol Biol ; 78(5): 427-39, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11738553

RESUMEN

Teleost fish are characterized by exceptionally high levels of neural estrogen biosynthesis when compared with the brains of other vertebrates or to the ovaries of the same fish. Two P450arom mRNAs which derive from separate gene loci (cyp19a and cyp19b) are differentially expressed in brain (b>>a) and ovary (a>>b) and have a different developmental program (b>>a) and estrogen upregulation (b only). A polymerase chain reaction (PCR)-based genomic walking strategy was used to isolate the 5'-flanking regions of the goldfish (Carassius auratus) cyp19 genes. Sequence analysis of the cyp19b gene approximately 1.8 kb upstream of the transcription start site revealed a TATA box at nucleotide (nt) -30, two estrogen responsive elements (EREs; nt -351 and -211) and a consensus binding site (NBRE) for nerve growth factor inducible-B protein (NGFI-B/Nur77) at -286, which includes another ERE half-site. Also present were a sequence at nt -399 (CCCTCCT) required for neural specificity of the zebrafish GATA-2 gene, and 16 copies of an SRY/SOX binding motif. The 5'-flanking region ( approximately 1.0 kb) of the cyp19a gene had TATA (nt -48) and CAAT (nt -71) boxes, a steroidogenic factor-1 (SF-1) binding site (nt -265), eight copies of the SRY/SOX motif, and two copies of a recognition site for binding the arylhydrocarbon receptor (AhR)/AhR nuclear translocator factor (ARNT) heterodimer. Both genes had elements previously identified in the brain specific exon I promoter of the mouse aromatase gene. Cyp19a- and -b/luciferase constructs showed basal promoter activity in aromatase-expressing rodent pituitary (GH3) cells, but differences (a>>b) did not reflect expression in fish pituitary in vivo (b>>a), implying a lack of appropriate cell factors. Consistent with the onset of cyp19b expression in zebrafish embryos, microinjection of a green fluorescent protein (GFP) reporter plasmid into fertilized eggs revealed labeling in neural tissues at 30-48 h post-fertilization (hpf), most prominently in retinal ganglion cells (RGC) and axon-like projections to the optic tectum. Expression of a cyp19a/GFP reporter was not detectable up to 72 hpf. Tandem analysis of cyp19a and cyp19b promoters in living zebrafish embryos can be a useful approach for identifying cis-elements and cellular factors involved in the correct tissue-specific, spatial, temporal and estrogen regulated expression of aromatase genes during CNS and gonadal development.


Asunto(s)
Aromatasa/genética , Encéfalo/metabolismo , Carpa Dorada/genética , Carpa Dorada/metabolismo , Ovario/metabolismo , Regiones Promotoras Genéticas , Animales , Animales Modificados Genéticamente , Secuencia de Bases , Encéfalo/crecimiento & desarrollo , Línea Celular , Clonación Molecular , ADN/genética , Femenino , Regulación del Desarrollo de la Expresión Génica , Genes Reporteros , Carpa Dorada/crecimiento & desarrollo , Proteínas Fluorescentes Verdes , Proteínas Luminiscentes/genética , Datos de Secuencia Molecular , Ovario/crecimiento & desarrollo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Homología de Secuencia de Ácido Nucleico , Distribución Tisular , Transfección , Pez Cebra/genética , Pez Cebra/metabolismo
14.
Acta Med Okayama ; 55(5): 269-76, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11688949

RESUMEN

To clarify the trend of hypercholesterolemia in Japanese adolescents, we investigated the serial changes in body mass index (BMI) and serum total cholesterol (TC) concentrations among 5,700 new students enrolled at Okayama University in 1989, 1993, and 1998. After confirming the stability of the TC assay of serum samples stored at -80 degrees C, we measured serum TC levels in stored serum samples using an automated assay system. Although serum TC levels were higher in females than in males, these levels correlated weakly and positively with BMI (r = 0.21, P < 0. 001) in males but not in females. Serum TC concentrations progressively increased from 1989-1998 in both sexes, irrespective of changes in BMI. In subjects with normal BMI (> or = 19 and < 23 kg/m2), a significant increase in serum TC was noted from 1989-1998 in both males (157.2 +/- 1.0 to 163.6 +/- 0.9 mg/dl) and females (172.0 +/- 1.1 to 175.6 +/- 1.0 mg/dl). Our results indicate on increased incidence of hypercholesterolemia even in nonobese young Japanese adolescents. A concerted effort by health and education officials together with parents is necessary to prevent a further rise in the incidence of hypercholesterolemia among young Japanese.


Asunto(s)
Colesterol/sangre , Estudiantes , Universidades , Adolescente , Adulto , Conservación de la Sangre , Índice de Masa Corporal , Femenino , Humanos , Hipercolesterolemia/epidemiología , Incidencia , Japón , Masculino , Caracteres Sexuales
15.
Hypertens Res ; 24(5): 589-94, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11675955

RESUMEN

We report a Japanese family with glucocorticoid-remediable aldosteronism (GRA) in whom gene abnormality was identified by the long-polymerase chain reaction (PCR) method. The proband was a 21-year-old female incidentally found to have high blood pressure (173/107 mmHg). Laboratory tests showed hypokalemia (3.7 mmol/l), and high plasma aldosterone concentration (PAC, 234 pg/ml) with suppressed plasma renin activity (PRA, <0.1 ng/ml/h). The circadian rhythm pattern and the results of a rapid adrenocorticotrophic hormone (ACTH) test indicated ACTH-dependent changes in PAC. Imaging studies showed no adrenal mass on either side. A dexamethasone (Dexa) suppression test (1.0 mg/day orally for 7 days) showed a marked decrease of PAC 2 days after administration, and this decreased level was maintained throughout Dexa administration. High blood pressure and hypokalemia also improved during Dexa treatment. The proband's younger sister was 19 years old and had hypertension, PAC of 231 pg/ml, and PRA <0.1 ng/ml/h. The mother was 53 years old and had hypertension, PAC of 98.5 pg/ml, and PRA <0.1 ng/ml/h. The proband's elder sister was a 22-year-old normotensive with PAC of 110 pg/ml and PRA of 0.1 ng/ml. Long-PCR was performed for detection of the chimeric gene associated with GRA, using DNA samples from all four cases and two normal control subjects. Although the aldosterone synthase gene was expressed among all DNA samples, the chimeric gene was detected only in the proband, her younger sister and her mother. Our clinical data and genetic investigation confirmed the presence of GRA in this Japanese family.


Asunto(s)
Hiperaldosteronismo/diagnóstico , Hiperaldosteronismo/genética , Reacción en Cadena de la Polimerasa/métodos , Adulto , Quimera , Citocromo P-450 CYP11B2/genética , Dexametasona , Salud de la Familia , Femenino , Glucocorticoides , Humanos , Hipertensión/genética , Japón , Persona de Mediana Edad , Linaje , Esteroide 11-beta-Hidroxilasa/genética
16.
Br J Pharmacol ; 134(4): 753-62, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11606315

RESUMEN

1. 3-Hydroxy-3-methylglutaryl co-enzyme A reductase inhibitors (statins) prevent the progression of atherosclerosis by lowering cholesterol. However, the effect of statins on the synthesis of pro-inflammatory cytokines from endothelial cells has not yet been fully investigated. Here, we examined the effect of pravastatin, one of the statins, on IL-8 synthesis induced by thrombin in human aortic endothelial cells (AoEC) cultured with high glucose concentrations. 2. Pravastatin significantly decreased the IL-8 synthesis induced by thrombin. 3. Pravastatin inhibited the p44/42 MAP kinase activity induced by thrombin, but did not inhibit the p38 MAP kinase activity. 4. Translocation of ras protein from the cytosol to plasma membrane was inhibited by pravastatin. 5. Pravastatin inhibit the activator protein-1 activity, but did not inhibit the activation of IkappaB-alpha. 6. Dominant negative ras inhibited the p44/42 MAP kinase activity induced by PMA. 7. Our results suggest that pravastatin inhibits IL-8 synthesis by blocking the ras-MAP (p44/42) kinase pathway rather than nuclear factor-kappaB. Pravastatin may prevent atherosclerosis not only by lowering cholesterol levels, but also by suppressing IL-8 synthesis in AoEC through the inhibition of p44/42 MAP kinase, and this may be more beneficial in diabetic patients than in non-diabetics.


Asunto(s)
Endotelio Vascular/efectos de los fármacos , Glucosa/farmacología , Proteínas I-kappa B , Interleucina-8/biosíntesis , Proteínas Quinasas Activadas por Mitógenos/antagonistas & inhibidores , Pravastatina/farmacología , Trombina/farmacología , Anticolesterolemiantes/farmacología , Aorta/citología , Aorta/efectos de los fármacos , Aorta/metabolismo , Western Blotting , Células Cultivadas , Proteínas de Unión al ADN/efectos de los fármacos , Proteínas de Unión al ADN/metabolismo , Relación Dosis-Respuesta a Droga , Endotelio Vascular/citología , Endotelio Vascular/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Interleucina-8/genética , Proteína Quinasa 1 Activada por Mitógenos/antagonistas & inhibidores , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Inhibidor NF-kappaB alfa , Fosforilación/efectos de los fármacos , Proteínas de Plantas , ARN Mensajero/efectos de los fármacos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Acetato de Tetradecanoilforbol/farmacología , Factor de Transcripción AP-1/efectos de los fármacos , Factor de Transcripción AP-1/metabolismo , Proteínas ras/efectos de los fármacos , Proteínas ras/metabolismo
17.
Atherosclerosis ; 157(2): 341-52, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11472733

RESUMEN

Vascular smooth muscle cells play a key role in the development of atherosclerosis. Culture of vascular smooth muscle A10 cells with high glucose for 4 weeks enhanced platelet-derived growth factor (PDGF)-induced BrdU incorporation. Since a long period of high glucose incubation was required for the effect, and it was inhibited by co-incubation with azaserine, the role of hexosamine biosynthesis in the development of atherosclerosis in diabetes was studied in A10 cells. Addition of glucosamine to the culture media enhanced PDGF-stimulated BrdU incorporation, and PDGF-induced tyrosine phosphorylation of the PDGF beta-receptor was increased by glucosamine treatment. Of the subsequent intracellular signaling pathways, PDGF-induced PDGF beta-receptor association with PLC gamma was not affected, whereas tyrosine phosphorylation of Shc, subsequent association of Shc with Grb2, and MAP kinase activation were relatively decreased. In contrast, PDGF-induced PDGF beta-receptor association with the p85 regulatory subunit of PI3-kinase and PI3-kinase activation were increased by 20% (P<0.01) and 36% (P<0.01), respectively. The intracellular signaling molecules responsible for the glucosamine effect were further examined using pharmacological inhibitors. Pretreatment with PLC inhibitor (U73122) had negligible effects, and MEK1 inhibitor (PD98059) showed only a slight inhibitory effect on the PDGF-induced BrdU incorporation. In contrast, pretreatment with PI3-kinase inhibitor (LY294002) significantly inhibited glucosamine enhancement of PDGF-induced BrdU incorporation. These findings suggest that glucosamine is involved in the development of atherosclerosis by enhancing PDGF-induced mitogenesis specifically via the PI3-kinase pathway.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Proteínas Adaptadoras del Transporte Vesicular , Aorta/metabolismo , ADN/biosíntesis , Glucosamina/farmacología , Músculo Liso Vascular/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Factor de Crecimiento Derivado de Plaquetas/farmacología , Animales , Aorta/citología , Aorta/efectos de los fármacos , Azaserina/farmacología , Bromodesoxiuridina/metabolismo , Células Cultivadas , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Inhibidores Enzimáticos/farmacología , Proteína Adaptadora GRB2 , Glucosa/farmacología , Isoenzimas/metabolismo , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Músculo Liso Vascular/citología , Músculo Liso Vascular/efectos de los fármacos , Fosfolipasa C gamma , Fosforilación/efectos de los fármacos , Proteínas/metabolismo , Ratas , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Proteínas Adaptadoras de la Señalización Shc , Proteína Transformadora 1 que Contiene Dominios de Homología 2 de Src , Fosfolipasas de Tipo C/metabolismo , Tirosina/metabolismo
18.
Endocr J ; 48(2): 255-60, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11456276

RESUMEN

We report a rare case of Graves' disease associated with struma ovarii. A 26-year-old Japanese woman had preexisting Graves' disease and was positive for TSH receptor antibody. She had been on antithyroid medication at presentation. She noted a mass in the lower left abdomen, which was diagnosed as a left struma ovarii by radiological work-up including computed tomography, magnetic resonance imaging and scintigraphy. The surgically excised teratomatous tumor, containing cystic spaces with thyroid tissue, was histologically proved to be struma ovarii. Since thyroid function tests and TSH receptor antibody did not change after surgery, her hyperthyroidism was considered to be due to Graves' disease. Our case was diagnosed as struma ovarii before surgery using various imaging studies.


Asunto(s)
Enfermedad de Graves/complicaciones , Neoplasias Ováricas/complicaciones , Estruma Ovárico/complicaciones , Adulto , Antitiroideos/uso terapéutico , Autoanticuerpos/sangre , Femenino , Enfermedad de Graves/diagnóstico , Enfermedad de Graves/tratamiento farmacológico , Humanos , Inmunoglobulinas Estimulantes de la Tiroides/sangre , Imagen por Resonancia Magnética , Metimazol/uso terapéutico , Neoplasias Ováricas/diagnóstico , Neoplasias Ováricas/cirugía , Ovariectomía , Cintigrafía , Receptores de Tirotropina/sangre , Estruma Ovárico/diagnóstico , Estruma Ovárico/cirugía , Hormonas Tiroideas/sangre , Tomografía Computarizada por Rayos X , Ultrasonografía
19.
J Biol Chem ; 276(35): 33147-55, 2001 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-11425858

RESUMEN

Although casein kinase Iepsilon (CKIepsilon) has been shown to regulate the Wnt signaling pathway positively, its mode of action is not clear. In this study we show that CKIepsilon activates the Wnt signaling pathway in co-operation with Dvl. CKIepsilon and Axin associated with different sites of Dvl, and CKIepsilon and Dvl interacted with distinct regions on Axin. Therefore, these three proteins formed a ternary complex. Either low expression of Dvl or CKIepsilon alone did not accumulate beta-catenin, but their co-expression accumulated greatly. Dvl and CKIepsilon activated the transcriptional activity of T cell factor (Tcf) synergistically. Although the Dvl mutant that binds to Axin but not to CKIepsilon activated Tcf, it did not synergize with CKIepsilon. Another Dvl mutant that does not bind to Axin did not activate Tcf irrespective of the presence of CKIepsilon. Furthermore, Dvl and CKIepsilon co-operatively induced axis duplication of Xenopus embryos. These results indicate that Dvl and CKIepsilon synergistically activated the Wnt signaling pathway and that the binding of the complex of Dvl and CKIepsilon to Axin is necessary for their synergistic action.


Asunto(s)
Fosfoproteínas/metabolismo , Proteínas Quinasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Represoras , Proteínas de Pez Cebra , Proteínas Adaptadoras Transductoras de Señales , Animales , Proteína Axina , Células COS , Caseína Quinasas , Chlorocebus aethiops , Clonación Molecular , Proteínas Dishevelled , Genes Reporteros , Humanos , Cinética , Fosfoproteínas/genética , Fosfoproteínas/aislamiento & purificación , Fosforilación , Unión Proteica , Proteínas Quinasas/aislamiento & purificación , Proteínas Tirosina Quinasas/metabolismo , Proteínas/genética , Proteínas/metabolismo , Ratas , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Transducción de Señal , Transfección , Proteínas Wnt , Proteínas de Xenopus
20.
Comp Biochem Physiol B Biochem Mol Biol ; 129(2-3): 261-8, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11399458

RESUMEN

Estrogen synthesized in the brain itself by the action of cytochrome P450 aromatase (P450arom) is known to have permanent organizing effects on the developing CNS. In fish, estrogen upregulates the predominant brain isoform (P450aromB), implying that xenoestrogens (XE) could act as neurodevelopmental toxicants by altering P450aromB. To test this hypothesis, zebrafish embryos were exposed to 17beta-estradiol (E(2)), diethylstilbestrol (DES, a potent agonist), and bisphenol A (BPA, a weak agonist). RT-PCR/Southern transfer analysis showed that E(2) (0.01-10 microM) upregulated P450aromB in a dose-response manner. The effect of DES (0.01 microM) was similar to 1 microM E(2) (three- to four-fold higher than control), but BPA was less effective (

Asunto(s)
Aromatasa/metabolismo , Encéfalo/metabolismo , Estrógenos/farmacología , Pez Cebra/embriología , Animales , Aromatasa/genética , Biomarcadores/análisis , Encéfalo/efectos de los fármacos , Encéfalo/enzimología , Relación Dosis-Respuesta a Droga , Inducción Enzimática/efectos de los fármacos , Estradiol/agonistas , Estradiol/farmacología , Estrógenos/agonistas , Isoenzimas/genética , Isoenzimas/metabolismo , Microscopía de Contraste de Fase , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Pez Cebra/metabolismo
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