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1.
Oral Dis ; 23(2): 199-209, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27868311

RESUMEN

OBJECTIVE: Ameloblastoma (AM) shows locally invasive behaviour. However, biological investigations regarding regulation of gene expression associated with AM pathological features are difficult to perform, because AM cells can be passaged for a few generations due to senescence. We report a newly established immortalized AM cell line, AMB cells, by transfection with human telomerase reverse transcriptase (hTERT). Furthermore, we examined whether TNF-α modulates bone resorption-related genes, IL-6 and MMP-9 in cooperation with TGF-ß or IFN-γ. MATERIALS AND METHODS: Following transfection of an hTERT expression vector into AM cells using a non-viral method, the effects of cytokines on the expressions of IL-6 and MMP-9 mRNA were examined using real-time PCR. TNF-α-induced NF-κB activity was examined by western blotting and transcription factor assays. RESULTS: AMB cells continued to grow for more than 100 population doublings. Stimulation with TNF-α increased IL-6 and MMP-9 mRNA expressions, as well as NF-κB activation. Furthermore, TGF-ß and IFN-γ dramatically increased TNF-α-mediated expressions of MMP-9 and IL-6 mRNA, respectively, while those responses were suppressed by NF-κB inhibitor. CONCLUSION: We established an immortalized AM cell line by hTERT transfection. TNF-α-mediated regulation of MMP-9 and IL-6 via NF-κB may play an important role in the pathological behaviour of AMs, such as bone resorption.


Asunto(s)
Ameloblastoma/genética , Expresión Génica/efectos de los fármacos , Interleucina-6/genética , Neoplasias Maxilomandibulares/genética , Metaloproteinasa 9 de la Matriz/genética , Factor de Necrosis Tumoral alfa/farmacología , Adulto , Ameloblastoma/metabolismo , Línea Celular Tumoral , Proliferación Celular , Senescencia Celular/genética , Femenino , Humanos , Interferón gamma/farmacología , Neoplasias Maxilomandibulares/metabolismo , FN-kappa B/antagonistas & inhibidores , FN-kappa B/metabolismo , Nitrilos/farmacología , ARN Mensajero/metabolismo , Sulfonas/farmacología , Telomerasa/genética , Transfección , Factor de Crecimiento Transformador beta/farmacología
2.
Oral Dis ; 21(1): 106-12, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24495175

RESUMEN

OBJECTIVE: Itraconazole (ICZ) has a broad spectrum of antifungal activity including a wide range of Candida spp. TNF-α, an inflammatory cytokine associated with Th1-mediated oral inflammatory disease, enhances inflammatory mediators, such as CXCR3-agonistic chemokines including CXCL10. We examined the anti-inflammatory potential of ICZ against TNF-α-induced chemokines in oral fibroblasts. MATERIALS AND METHODS: We investigated the effects of ICZ on mRNA expressions of various TNF-α-induced chemokines in immortalized oral keratinocytes (RT7) and oral fibroblasts (GT1) using quantitative PCR analysis. Subsequently, the effects of ICZ and fluconazole (FLZ) on TNF-α-induced CXCL10 proteins in GT1 and primary fibroblasts were examined using enzyme-linked immunosorbent assays (ELISA). The effect of ICZ on signal transduction protein phosphorylation involved in CXCL10 production from TNF-α-stimulated GT1 was examined by western blotting. RESULTS: ICZ inhibited TNF-α-induced CXCL10 mRNA in GT1, but not RT7. Although ICZ did not affect TNF-α-induced IL-8 mRNA, the mRNAs of TNF-α-induced CXCR3-agonistic chemokines such as CXCL9 and CXCL11 were inhibited by ICZ in GT1. TNF-α-induced CXCL10 protein production in GT1 and primary fibroblasts was inhibited by ICZ, but not FLZ. Finally, ICZ inhibited TNF-α-induced phosphorylation of c-JUN, which is related to CXCL10 production by TNF-α-stimulated GT1. CONCLUSION: ICZ may be useful as therapy for Th1-mediated oral inflammatory disease.


Asunto(s)
Antifúngicos/farmacología , Quimiocina CXCL10/biosíntesis , Fibroblastos/fisiología , Itraconazol/farmacología , Queratinocitos/fisiología , Boca/citología , Factor de Necrosis Tumoral alfa/farmacología , Western Blotting , Línea Celular , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Fluconazol/farmacología , Humanos , Queratinocitos/efectos de los fármacos , Queratinocitos/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
3.
Clin Exp Nephrol ; 16(2): 269-78, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22127399

RESUMEN

BACKGROUND: Achieving adequate blood pressure (BP) control often requires more than one antihypertensive agent. The purpose of this study was to determine whether a fixed-dose formulation of losartan (LOS) plus hydrochlorothiazide (HCTZ) (LOS/HCTZ) is effective in achieving a greater BP lowering in patients with uncontrolled hypertension. METHODS: The study was a prospective, multicenter, observational trial exploring the antihypertensive effect of a single tablet of LOS 50 mg/HCTZ 12.5 mg. A total of 228 patients whose BP had previously been treated with more than one antihypertensive agents without having achieved BP goal below 130/80 mmHg enrolled in the study. RESULTS: A significant decrease in systolic and diastolic BP was observed in both clinic and home measurement after switching from the previous treatment to LOS/HCTZ. There was a significant decrease in both B-type natriuretic peptide (BNP) and urinary albumin creatinine (Cr) excretion ratio (ACR), especially in patients with elevated values. In contrast, there was a significant increase in serum Cr concentration in conjunction with a decrease in estimated glomerular filtration rate (eGFR). Overall serum uric acid (UA) concentration increased, whereas in patients with hyperuricemia there was a significant reduction in this value. CONCLUSION: Switching to LOS/HCTZ provides a greater reduction in clinic and home BP in patients with uncontrolled hypertension. This combination therapy may lead to cardio-, reno protection and improve UA metabolism.


Asunto(s)
Antihipertensivos/uso terapéutico , Presión Sanguínea/efectos de los fármacos , Hidroclorotiazida/uso terapéutico , Hipertensión/tratamiento farmacológico , Losartán/uso terapéutico , Adulto , Anciano , Determinación de la Presión Sanguínea , Creatinina/orina , Combinación de Medicamentos , Femenino , Tasa de Filtración Glomerular , Humanos , Hipertensión/metabolismo , Hipertensión/fisiopatología , Hiperuricemia , Japón , Masculino , Persona de Mediana Edad , Péptido Natriurético Encefálico/sangre , Estudios Prospectivos , Resultado del Tratamiento , Ácido Úrico/sangre , Adulto Joven
4.
Science ; 371(6533): 1038-1041, 2021 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-33674491

RESUMEN

Spectroscopy of transiting exoplanets can be used to investigate their atmospheric properties and habitability. Combining radial velocity (RV) and transit data provides additional information on exoplanet physical properties. We detect a transiting rocky planet with an orbital period of 1.467 days around the nearby red dwarf star Gliese 486. The planet Gliese 486 b is 2.81 Earth masses and 1.31 Earth radii, with uncertainties of 5%, as determined from RV data and photometric light curves. The host star is at a distance of ~8.1 parsecs, has a J-band magnitude of ~7.2, and is observable from both hemispheres of Earth. On the basis of these properties and the planet's short orbital period and high equilibrium temperature, we show that this terrestrial planet is suitable for emission and transit spectroscopy.

5.
Mol Cell Biol ; 21(1): 330-42, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11113207

RESUMEN

In attempting to clarify the roles of Dvl in the Wnt signaling pathway, we identified a novel protein which binds to the PDZ domain of Dvl and named it Idax (for inhibition of the Dvl and Axin complex). Idax and Axin competed with each other for the binding to Dvl. Immunocytochemical analyses showed that Idax was localized to the same place as Dvl in cells and that expression of Axin inhibited the colocalization of Dvl and Idax. Further, Wnt-induced accumulation of beta-catenin and activation of T-cell factor in mammalian cells were suppressed by expression of Idax. Expression of Idax in Xenopus embryos induced ventralization with a reduction in the expression of siamois, a Wnt-inducible gene. Idax inhibited Wnt- and Dvl- but not beta-catenin-induced axis duplication. It is known that Dvl is a positive regulator in the Wnt signaling pathway and that the PDZ domain is important for this activity. Therefore, these results suggest that Idax functions as a negative regulator of the Wnt signaling pathway by directly binding to the PDZ domain of Dvl.


Asunto(s)
Proteínas Portadoras/metabolismo , Fosfoproteínas/metabolismo , Proteínas/metabolismo , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Proteínas Represoras , Transducción de Señal , Transactivadores , Proteínas de Pez Cebra , Proteínas Adaptadoras Transductoras de Señales , Secuencia de Aminoácidos , Animales , Proteína Axina , Tipificación del Cuerpo , Proteínas Portadoras/química , Proteínas Portadoras/genética , Proteínas Portadoras/aislamiento & purificación , Proteínas del Citoesqueleto/metabolismo , Proteínas de Unión al ADN , Proteínas Dishevelled , Regulación del Desarrollo de la Expresión Génica , Genes Reporteros , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Inmunohistoquímica , Datos de Secuencia Molecular , Unión Proteica , Estructura Terciaria de Proteína , Proteínas/química , Proteínas/genética , Proteínas/aislamiento & purificación , Proteínas Proto-Oncogénicas/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Factores de Transcripción , Técnicas del Sistema de Dos Híbridos , Proteínas Wnt , Xenopus/embriología , Proteínas de Xenopus , beta Catenina
6.
Mon Not R Astron Soc ; 457(4): 4089-4113, 2016 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-32848283

RESUMEN

We present a statistical analysis of the first four seasons from a "second-generation" microlensing survey for extrasolar planets, consisting of near-continuous time coverage of 8 deg2 of the Galactic bulge by the OGLE, MOA, and Wise microlensing surveys. During this period, 224 microlensing events were observed by all three groups. Over 12% of the events showed a deviation from single-lens microlensing, and for ~1/3 of those the anomaly is likely caused by a planetary companion. For each of the 224 events we have performed numerical ray-tracing simulations to calculate the detection efficiency of possible companions as a function of companion-to-host mass ratio and separation. Accounting for the detection efficiency, we find that 55 - 22 + 34 % of microlensed stars host a snowline planet. Moreover, we find that Neptunes-mass planets are ~ 10 times more common than Jupiter-mass planets. The companion-to-host mass ratio distribution shows a deficit at q ~ 10-2, separating the distribution into two companion populations, analogous to the stellar-companion and planet populations, seen in radial-velocity surveys around solar-like stars. Our survey, however, which probes mainly lower-mass stars, suggests a minimum in the distribution in the super-Jupiter mass range, and a relatively high occurrence of brown-dwarf companions.

7.
Mol Immunol ; 35(9): 537-44, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9809581

RESUMEN

We designed a cDNA construct encoding an artificial membrane molecule consisting of all 8 short consensus repeats (SCRs) of human monomeric C4b-binding protein (C4bp) followed by DAF's GPI anchor, named mC4bp, and expressed the protein on swine endothelial cells (SEC). At the same level of expression, mC4bp protected host cells as effectively as DAF, the most potent complement (C) regulator on the membrane. This result was unexpected from the reported functional properties of natural multimeric C4bp. Here, we investigated the mechanism whereby mC4bp has potent cell-protective activity. Our results were as follows: (1) mC4bp serves more efficiently as a methylamine-treated C3 (C3ma)-inactivating factor I-cofactor than natural C4bp and as efficiently as MCP as a methylamine-treated (C4ma)-inactivating cofactor by fluid-phase cofactor assay: (2) the potency of C3ma inactivation by mC4bp and factor I is quite high compared to those of other cofactors: (3)blocking studies using mAbs against C4bp suggested that both the 48 kDa N-terminal fragment and the C-terminal domain near the portion responsible for bundle formation participate in the high C3ma-inactivating capacity of mC4bp. Thus, acquiring high C3ma-inactivating capacity secondary to monomeric alteration leads to high C regulatory activity of mC4bp. These results infer that mC4bp differs from C4bp in its potent factor I-cofactor activity and is a good candidate as a safeguard against hyperacute rejection of xenografts.


Asunto(s)
Proteínas Inactivadoras del Complemento C3b/metabolismo , Proteínas Inactivadoras de Complemento , Glicoproteínas , Receptores de Complemento/metabolismo , Proteínas Inactivadoras del Complemento C3b/química , Proteínas Inactivadoras del Complemento C3b/genética , Factor I de Complemento/metabolismo , Glicosilfosfatidilinositoles , Humanos , Fragmentos de Péptidos , Conformación Proteica , Receptores de Complemento/química , Receptores de Complemento/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Secuencias Repetitivas de Aminoácido
8.
Cardiovasc Res ; 31(6): 899-906, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8759245

RESUMEN

OBJECTIVE: Little is known as to whether an increase in coronary perfusion pressure can alter the right ventricular (RV) distensibility and the contractile function as it does in the case of the LV. METHODS: In eight isolated isovolumically contracting canine hearts, RV and LV volumes and coronary perfusion were independently controlled. Effects of an increase in coronary perfusion pressure (from 73 +/- 1 to 152 +/- 6 mmHg) on the end-diastolic and end-systolic pressure-volume relations in both RV and LV were assessed. RESULTS: Following an increase in coronary perfusion, and at a similar volume of the ventricles, end-diastolic pressure was elevated by 2.8 +/- 0.8 mmHg in RV and 8.9 +/- 2.0 mmHg in LV (P < 0.01; RV vs LV), and the slope of RV end-systolic pressure-volume relation, Ees, increased by 11 +/- 6% (P < 0.05) and that of the LV Ees by 21 +/- 5% (P < 0.01). The percent change of RV pressure-volume area (PVA) was less than that in LV-PVA (26 +/- 9 vs 48 +/- 11%; P < 0.05). CONCLUSIONS: Accordingly, increases in coronary perfusion pressure and/or flow decreased the RV distensibility and enhanced the RV contractile function, the extent of which, however, was less than that in the LV.


Asunto(s)
Presión Sanguínea/fisiología , Circulación Coronaria/fisiología , Contracción Miocárdica/fisiología , Función Ventricular Derecha/fisiología , Animales , Perros , Perfusión , Volumen Sistólico , Sístole , Función Ventricular Izquierda/fisiología
9.
Int J Dev Biol ; 38(2): 257-66, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7981034

RESUMEN

We reviewed cell differentiation and morphogenesis by mesoderm-inducing factors during amphibian embryogenesis. Recently, two kinds of growth factors, activin and FGF, have been identified as influential candidates for natural mesoderm-inducing factor in amphibian development. These factors are present in early Xenopus embryos. In particular, activin has been shown to induce many kinds of mesodermal tissues in a dose-dependent manner. Activin-treated ectodermal sheet (animal cap) acts as an organizer causing gene expression, mesoderm formation and functional events such as secondary axis formation. Follistatin, an activin-specific binding protein, also present in the early Xenopus embryo, makes a complex with activin. Follistatin protein exerts no inducing activity of Xenopus animal cap. Endogenous follistatin may, however, play the role of an activin regulation factor. Endogenous actions of activin and FGF were studied using injection of their receptor mRNAs. Disruption of the FGF signaling pathway by its non-functional dominant negative receptors produced trunk and tail defects. In the case of activin, an embryo cannot form axial structures. Animal-half blastomeres from the late 8-cell stage Xenopus embryo respond to activin, and there are prepatterns in ventral and dorsal cells from very early stages. The timing of mesoderm induction during development and the relationship between the inducing factors and competent cells are discussed in this report. Differentiation of tissues and organized formation of organs can be understood as a system of serial inductive reactions originating from the organizer. We have attempted to construct a model of organizer formation based on the results of recent studies.


Asunto(s)
Xenopus/embriología , Activinas , Animales , Diferenciación Celular/efectos de los fármacos , Desarrollo Embrionario y Fetal/efectos de los fármacos , Desarrollo Embrionario y Fetal/genética , Factores de Crecimiento de Fibroblastos/farmacología , Regulación del Desarrollo de la Expresión Génica , Sustancias de Crecimiento/farmacología , Inhibinas/farmacología , Tretinoina/farmacología , Xenopus/genética
10.
Gene ; 203(2): 183-8, 1997 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-9426249

RESUMEN

Out of a Xenopus neurula cDNA library, we isolated a clone which encodes a 52.4-kDa protein highly similar to the mouse interferon regulatory factor, IRF-6, whose function is unknown. The mRNA of this gene, named xIRF-6, seems to be maternally transmitted, but its amount rapidly decreases after the tailbud stage. Whole-mount in situ hybridization showed that xIRF-6 mRNA is expressed in the presumptive somitic mesoderm in the late gastrula, and then confined to a segment of posterior somite during the neurula through the tailbud stage. The temporally and spatially limited expression of the xIRF-6 gene product may contribute to the transcriptional regulation of specific genes which are necessary for the development of the posterior somites.


Asunto(s)
Proteínas de Unión al ADN/genética , Embrión no Mamífero/metabolismo , Regulación del Desarrollo de la Expresión Génica , Mesodermo/metabolismo , Factores de Transcripción/genética , Proteínas de Xenopus , Xenopus laevis/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Northern Blotting , Clonación Molecular , ADN Complementario , Proteínas de Unión al ADN/química , Gástrula/metabolismo , Hibridación in Situ , Factores Reguladores del Interferón , Datos de Secuencia Molecular , ARN Mensajero/genética , ARN Mensajero/metabolismo , Análisis de Secuencia de ADN , Factores de Transcripción/química , Xenopus laevis/embriología
11.
Am J Cardiol ; 83(10): 1500-3, A8, 1999 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-10335772

RESUMEN

The circulating levels of soluble Fas ligand was increased in patients with advanced congestive heart failure. This study also indicates that the failing heart may contribute to the increased concentration of soluble Fas ligand in patients with congestive heart failure.


Asunto(s)
Insuficiencia Cardíaca/sangre , Glicoproteínas de Membrana/sangre , Miocardio/metabolismo , Adulto , Anciano , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Masculino , Persona de Mediana Edad , Solubilidad
12.
Invest Radiol ; 29(8): 758-65, 1994 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7960626

RESUMEN

RATIONALE AND OBJECTIVES: The reproducibility of repeated magnetic resonance (MR) spectroscopy was studied in patients undergoing dialysis and treatment of a variety of malignant tumors. METHODS: Localized MR spectra were obtained using a 1.5-T system by image-selected in vivo spectroscopy. Total metabolite signal was integrated between phosphomonoester and beta-adenosine triphosphate resonance. We termed this measurement AREA. RESULTS: Intrapatient variability was evaluated on repeated thigh muscle spectroscopy for 10 patients. Sequential spectra of 10 malignant tumors of the extremities were analyzed and compared with the histology of surgical specimens in seven patients. Intrapatient variability in AREA was calculated as 14.0%. The extent of necrosis and AREA ratio (definition: AREA post-therapy/AREA pretherapy) were as follows; 6.1% in > 90% necrosis, 43% in 50% to 90% necrosis, and 79% in < 50% necrosis. CONCLUSIONS: Localized MR spectra are fairly reproducible and may relate to treatment efficacy.


Asunto(s)
Neoplasias Óseas/metabolismo , Fallo Renal Crónico/metabolismo , Espectroscopía de Resonancia Magnética , Osteosarcoma/metabolismo , Diálisis Renal , Neoplasias de los Tejidos Blandos/metabolismo , Adolescente , Adulto , Anciano , Neoplasias Óseas/terapia , Femenino , Humanos , Fallo Renal Crónico/terapia , Masculino , Persona de Mediana Edad , Músculo Esquelético/metabolismo , Osteosarcoma/terapia , Reproducibilidad de los Resultados , Neoplasias de los Tejidos Blandos/terapia , Muslo
13.
J Appl Physiol (1985) ; 91(1): 435-40, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11408461

RESUMEN

Acute and chronic alterations of right ventricular (RV) wall properties can change left ventricular (LV) performance. We investigated whether and how stiffening of the RV free wall alters LV diastolic distensibility. We used cross-circulated isolated hearts, in which the LV and RV were independently controllable. Stiffness of the RV free wall was altered by intramuscular injections of glutaraldehyde into the RV free wall after right coronary artery ligation. We measured circumferential and longitudinal regional lengths in the septum and LV free wall. During data acquisition, RV volume was held constant. After the RV free wall was stiffened by glutaraldehyde, the LV diastolic pressure-volume relation shifted upward and became steeper. Importantly, stiffening of the RV free wall increased the diastolic regional area in the septum and LV free wall under constant LV volume. The augmented regional dimensions may result in enhanced regional tension under constant LV volume and may be related to the observed increase in LV diastolic intracavitary pressure. The impaired LV diastolic distensibility by stiffening of the RV free wall may be at least partly explained by myocardial stretch, probably due to LV deformation.


Asunto(s)
Contracción Miocárdica , Disfunción Ventricular Izquierda/etiología , Disfunción Ventricular Izquierda/fisiopatología , Disfunción Ventricular Derecha/complicaciones , Animales , Volumen Sanguíneo , Diástole , Perros , Elasticidad , Glutaral/administración & dosificación , Técnicas In Vitro , Inyecciones Intramusculares , Músculos Papilares , Presión , Disfunción Ventricular Derecha/inducido químicamente
14.
Fertil Steril ; 68(6): 997-9, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9418686

RESUMEN

OBJECTIVE: To investigate the efficacy of clomiphene citrate (CC) on normally ovulatory women who complained of infertility. DESIGN: A randomized study. SETTING: University Hospital. PATIENT(S): Thirty-three normally ovulatory women with unexplained infertility. INTERVENTION(S): Eighteen women received CC at a 50-mg dosage. Fifteen women received no ovulation-induction drugs. MAIN OUTCOME MEASURES: The pregnancy rate (PR) per patient, the PR per cycle, and the cumulative pregnancy rate. RESULT(S): Seven patients in the CC group stopped taking CC, and observations were terminated because of antiestrogenic effects. The pregnancy rate (PR) per patient and the PR per cycle were significantly decreased (P < 0.005) in the CC group (4 of 18 [22.2%] and 4 of 66 [6.1%], respectively) than in the spontaneous group (11 of 15 [73.3%] and 11 of 52 [21.2%], respectively). Kaplan-Meier tests showed that the cumulative pregnancy rate in the CC group was significantly lower than in the spontaneous group (P < 0.05). Five of seven patients who had stopped taking CC became pregnant in spontaneous cycles. CONCLUSION(S): Administration of CC to normally ovulatory women is not efficacious in terms of increasing the pregnancy rate.


Asunto(s)
Clomifeno/farmacología , Fármacos para la Fertilidad Femenina/farmacología , Fertilización/efectos de los fármacos , Infertilidad Femenina/tratamiento farmacológico , Ovulación , Adulto , Clomifeno/uso terapéutico , Femenino , Fármacos para la Fertilidad Femenina/uso terapéutico , Humanos , Embarazo , Insuficiencia del Tratamiento
15.
Int J Mol Med ; 3(1): 25-32, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9864382

RESUMEN

Human membrane cofactor protein (MCP, CD46) is a regulator of complement activation and also serves as a receptor for measles virus (MV). We recently isolated an MCP homolog from B95a, an Epstein-Barr virus-transformed marmoset B-lymphoblastoid cell line, which is 76% identical to human-MCP. B95a-MCP acts as an MV receptor for CAM, a vaccine strain of MV, but not for Nagahata, wild-type MV strain. The four residues in human-MCP (Asp27, Lys29, Arg69, and Asp70) are reportedly MV binding sites, and these are changed in B95a-MCP (Glu27, Asp29, Pro69, and Asn70). In the present study, we constructed B95a-MCP mutants by replacing the four residues with those in human-MCP, and tested whether the Chinese hamster ovary (CHO) transfectants expressing B95a-MCP mutants become susceptible to the Nagahata strain. The CHO transfectants expressing B95a-MCP mutants formed syncytium with the CAM strain but not with the Nagahata strain. The binding of the hemagglutinin (H) of MV with B95a-MCP mutants was observed with the CAM strain but not with the Nagahata strain. These results suggest that the failure of B95a-MCP as the MV receptor for the Nagahata strain is not due simply to the natural mutations at these four residues. The critical residues for MV binding in an MCP molecule seem to differ depending upon the structure of the MV H protein.


Asunto(s)
Aminoácidos/genética , Antígenos CD/genética , Virus del Sarampión/metabolismo , Glicoproteínas de Membrana/genética , Receptores Virales/metabolismo , Secuencia de Aminoácidos , Animales , Células CHO/citología , Células CHO/metabolismo , Células CHO/virología , Línea Celular Transformada , Chlorocebus aethiops , Complemento C3b/metabolismo , Cricetinae , Fibrinógeno/metabolismo , Expresión Génica , Vectores Genéticos/genética , Células Gigantes/virología , Virus del Sarampión/genética , Proteína Cofactora de Membrana , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Mutación , Homología de Secuencia de Aminoácido , Células Vero , Vacunas Virales/genética
16.
Mutat Res ; 81(1): 27-36, 1981 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7019685

RESUMEN

As reported in the previous paper, the number of deoxyribodipyrimidine photolyase or photoreactivating enzyme (PRE) molecules per yeast cell was determined by the use of intense light flashes. In the present work, the reaction rate constant for the formation of PRE-substrate complexes, k1, and the activation energy term of k1 were determined by yeast cells in vivo by the use of light flashes. At 30 degrees C, k1 equalled (6.5 +/- 1.1) x 10(-5) (nuclear volume) x (molecule)(-1) sec(-1), which corresponded to 1.1 x 10(5) 1 mole(-1) sec(-1), on the assumption that a nuclear volume is 3 x 10(-15) 1. k1 showed positive temperature dependence as described by the arrhenius expression with an activation energy of 11.8 +/- 1.6 kcal mole(-1).


Asunto(s)
Reparación del ADN/efectos de la radiación , Desoxirribodipirimidina Fotoliasa/metabolismo , Luz , Liasas/metabolismo , Dímeros de Pirimidina/metabolismo , Saccharomyces cerevisiae/genética , Relación Dosis-Respuesta en la Radiación , Cinética , Matemática , Factores de Tiempo
17.
J Antibiot (Tokyo) ; 46(7): 1139-44, 1993 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8360110

RESUMEN

A new macrolide antibiotic, PC-766B, was isolated from the cells of Nocardia brasiliensis SC-4710 by acetone extraction, and purified by gel filtration, silica gel chromatography, HPLC and TLC. The structure of PC-766B was determined by NMR spectral analysis to be a new class of the hygrolidin family antibiotics. PC-766B had a 16-membered macrocyclic lactone ring, a 6-membered hemiketal ring and a 2-deoxy-D-rhamnose moiety. DL-alpha-Tocopherol, known as an antioxidant agent, significantly improved the stability of PC-766B and prevented the decomposition of PC-766B during the storage of the antibiotic.


Asunto(s)
Antibacterianos , Macrólidos , Nocardia/metabolismo , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Fenómenos Químicos , Química Física , Estructura Molecular
18.
J Antibiot (Tokyo) ; 46(6): 972-8, 1993 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8393851

RESUMEN

An actinomycete strain SC-4710, a new soil isolate, was found to produce a new macrolide antibiotic, PC-766B. Chemotaxonomic analysis of the producing organism revealed that the cells of SC-4710 had type IV cell wall, type A whole cell sugar pattern, type PII phospholipids, menaquinone MK-8(H4), cellular fatty acids comprising straight-chain saturated, unsaturated and tuberculostearic acids, and mycolic acids. The strain was identified as Nocardia brasiliensis (Lindenberg) Pinoy. The antibiotic, PC-766B, was active against Gram-positive bacteria, and some fungi and yeasts, but inactive against Gram-negative bacteria. It also showed antitumor activity against murine tumor cells in vitro and in vivo, and a weak inhibitory activity against Na+, K(+)-ATPase in vitro.


Asunto(s)
Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Nocardia/química , Animales , Cromatografía Líquida de Alta Presión , Fermentación , Leucemia P388/tratamiento farmacológico , Macrólidos , Masculino , Ratones , Pruebas de Sensibilidad Microbiana , ATPasa Intercambiadora de Sodio-Potasio/antagonistas & inhibidores , Células Tumorales Cultivadas
19.
Nucl Med Commun ; 24(8): 901-6, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12869823

RESUMEN

This study aimed to examine whether angiotensin-converting enzyme (ACE) inhibition improved cardiac fatty acid metabolism in patients with congestive heart failure (CHF). Myocardial 123I-beta-methyl-iodophenylpentadecanoic acid (123I-BMIPP) imaging was performed in 25 patients with CHF and in 10 control subjects. Myocardial 123I-BMIPP images were obtained 30 min and 4 h after tracer injection. The heart-to-mediastinum (H/M) ratio of 123I-BMIPP uptake and the washout rate of 123I-BMIPP from the myocardium were calculated. Patients were given enalapril for 6 months, and 123I-BMIPP imaging was repeated. H/M ratios on early and delayed images were lower in CHF patients than in normal controls (P<0.01). The washout rate of 123I-BMIPP from the myocardium was faster in CHF patients than in controls (P<0.01). As the severity of the New York Heart Association (NYHA) functional class increased, the H/M ratio decreased and the washout rate increased. The washout rate of 123I-BMIPP was inversely correlated with left ventricular fractional shortening (R=-0.62, P<0.01). ACE inhibition with enalapril increased the H/M ratio on delayed images (P<0.05) and reduced the washout rate of 123I-BMIPP (P<0.05) in CHF patients. These data suggest that: (1) angiotensin II-mediated intracellular signalling activation may be a possible mechanism for the decreased myocardial uptake and enhanced washout of 123I-BMIPP in heart failure patients; and (2) the improvement in fatty acid metabolism by ACE inhibition may represent a new mechanism for the beneficial effect of this therapy in heart failure.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/administración & dosificación , Enalapril/administración & dosificación , Ácidos Grasos/metabolismo , Insuficiencia Cardíaca/metabolismo , Corazón/efectos de los fármacos , Corazón/diagnóstico por imagen , Yodobencenos , Miocardio/metabolismo , Ácidos Grasos/farmacocinética , Femenino , Insuficiencia Cardíaca/tratamiento farmacológico , Humanos , Yodobencenos/farmacocinética , Masculino , Persona de Mediana Edad , Cintigrafía , Radiofármacos/farmacocinética
20.
Nucl Med Commun ; 23(12): 1197-204, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12464785

RESUMEN

The aim of the present study was to examine whether Doppler tissue imaging demonstrated comparable diagnostic performance for the detection of viable myocardium compared to myocardial perfusion imaging with Tc hexakis-2-methoxyisobutylisonitrile (MIBI). We studied 30 patients with old myocardial infarction who underwent percutaneous transluminal coronary angioplasty (PTCA). Myocardial single photon emission computed tomography (SPECT) with Tc-MIBI and two-dimensional echocardiography were carried out within 7 days before PTCA. We measured regional Tc-MIBI uptake for each myocardial segment from SPECT and peak systolic velocity and a ratio of regional pre-ejection period to regional ejection time (PEP/ET) from pulsed Doppler tissue imaging. Biplane left ventriculography was performed before interventional procedures and repeated 3 months after PTCA. Myocardial viability was determined when wall motion was improved at least one grade after PTCA. The peak systolic velocity was positively correlated with regional Tc-MIBI uptake (R =0.59, P<0.01). The PEP/ET demonstrated inverse correlation with Tc-MIBI uptake ( R=-0.59, P<0.01). Peak systolic velocity of viable segments was higher than that of non-viable segments ( P<0.05). The PEP/ET was lower in viable segments than in non-viable segments ( P<0.05). Peak systolic velocity and PEP/ET demonstrated high diagnostic accuracy for detecting viable myocardium compared with Tc-MIBI perfusion imaging (80% and 79% vs 90%). These data indicate that measurements of regional peak systolic velocity and PEP/ET by Doppler tissue imaging are useful for evaluating myocardial viability quantitatively and provide helpful information for a clinical judgment in an interventional strategy.


Asunto(s)
Ecocardiografía Doppler de Pulso , Corazón/diagnóstico por imagen , Corazón/fisiopatología , Radiofármacos , Tecnecio Tc 99m Sestamibi , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/diagnóstico por imagen , Infarto del Miocardio/fisiopatología , Infarto del Miocardio/cirugía , Revascularización Miocárdica , Ventriculografía con Radionúclidos , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Izquierda/fisiopatología , Función Ventricular Izquierda/fisiología
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