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1.
Lupus ; 23(4): 342-52, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24474704

RESUMEN

OBJECTIVE: A glycosylated transmembrane protein, CD147, has been implicated in regulating lymphocyte responsiveness and leukocyte recruitment. As lupus nephritis (LN) often follows a relapsing-remitting disease course, accurate understanding of the disease activity would be extremely helpful in improving prognosis. Unfortunately, neither clinical nor serological data can accurately reflect the histological features of LN. The present study investigated whether CD147 can accurately predict pathological features of LN. METHODS: Plasma and spot urine samples were collected from 64 patients who underwent renal biopsy between 2008 and 2011. Disease activity for LN tissues was evaluated using the biopsy activity index, and compared to levels of biomarkers including CD147. RESULTS: In LN tissues, CD147 induction was striking in injured glomeruli and infiltrating inflammatory cells, but not in damaged tubules representing atrophy. Plasma CD147 levels accurately reflected the histological disease activity. However, prediction using a single molecule would be quite difficult because of the complex pathogenesis of LN. The diagnostic accuracy of multiplex parameters indicated that the combination including plasma CD147 might yield excellent diagnostic abilities for guiding ideal LN therapy. CONCLUSION: Plasma CD147 levels might offer useful insights into disease activity as a crucial biomarker in patients with LN.


Asunto(s)
Basigina/sangre , Nefritis Lúpica/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Estudios de Casos y Controles , Femenino , Humanos , Nefritis Lúpica/sangre , Nefritis Lúpica/diagnóstico , Masculino , Persona de Mediana Edad , Pronóstico , Adulto Joven
2.
Clin Oncol (R Coll Radiol) ; 34(12): e505-e514, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35654667

RESUMEN

AIMS: Although palliative radiotherapy for gastric cancer may improve some symptoms, it may also have a negative impact due to its toxicity. We investigated whether symptoms improved after radiotherapy with adjustment for the Palliative Prognostic Index (PPI) considering that patients with limited survival tend to experience deterioration of symptoms. MATERIALS AND METHODS: This study was an exploratory analysis of the Japanese Radiation Oncology Study Group study (JROSG 17-3). We assessed six symptom scores (nausea, anorexia, fatigue, shortness of breath, pain at the irradiated area and distress) at registration and 2, 4 and 8 weeks thereafter. We tested whether symptoms linearly improved after adjusting for the baseline PPI. Shared parameter models were used to adjust for potential bias in missing data. RESULTS: The present study analysed all 55 patients enrolled in JROSG 17-3. With time from registration as the only explanatory variable in the model, a significant linear decrease was observed in shortness of breath, pain and distress (slopes, -0.26, -0.22 and -0.19, respectively). Given that the interaction terms (i.e. PPI × time) were not significantly associated with symptom scores in any of the six symptoms, only PPI was included as the main effect in the final multivariable models. After adjusting for the PPI, shortness of breath, pain and distress significantly improved (slope, -0.25, -0.19 and -0.17; P < 0.001, 0.002 and 0.047, respectively). An improvement in fatigue and distress was observed only in patients treated with a biologically effective dose ≤14.4 Gy. CONCLUSION: Shortness of breath, pain and distress improved after radiotherapy. Moreover, a higher PPI was significantly associated with higher symptom scores at all time points, including baseline. In contrast, PPI did not seem to influence the improvement of these symptoms. Regardless of the expected survival, patients receiving radiotherapy for gastric cancer can expect an improvement in shortness of breath, pain and distress over 8 weeks. Multiple-fraction radiotherapy might hamper the improvement in fatigue and distress by its toxicity or treatment burden.


Asunto(s)
Oncología por Radiación , Neoplasias Gástricas , Humanos , Pronóstico , Neoplasias Gástricas/complicaciones , Neoplasias Gástricas/radioterapia , Cuidados Paliativos , Fatiga/etiología , Dolor/etiología , Dolor/radioterapia , Dolor/diagnóstico , Disnea/etiología , Disnea/radioterapia
3.
Science ; 258(5082): 618-25, 1992 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-17748896

RESUMEN

The Japanese Yohkoh satellite is now in orbit observing the sun with a set of x-ray imagers and x-ray and gamma-ray spectrometers. The data from this successful mission provide new information on solar flares and the sun's corona. This paper discusses the Yohkoh observations and presents a sample of the first scientific results from the mission.

4.
Transplant Proc ; 50(10): 3440-3444, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30577218

RESUMEN

OBJECTIVE: To improve the long-term survival rate after kidney transplantation (KTx), allograft injury should be identified as soon as possible. Regardless of aggressive immunosuppressive therapies, recipients of kidney transplants still have a significant risk of graft failure. No specific predictor for the progression of chronic kidney disease (CKD) after KTx has yet been found. Aberrant molecular mechanisms involving the αKlotho-fibroblast growth factor (FGF) 23 axis may be a useful determinant of renal impairment and graft failure over time. METHODS: Plasma and spot urine samples were collected from 47 patients 1 year after KTx. Evaluation of renal function after KTx was performed using levels of biomarkers including serum intact FGF23, soluble αKlotho, 25(OH) vitamin D (25(OH)D), and the difference in the estimated glomerular filtration rate (eGFR) between the first and third year after KTx (ΔeGFR). RESULTS: The median serum αKlotho, intact FGF23, and 25(OH)D were 516.3 pg/mL, 58.7 pg/mL, and 5.7 ng/mL, respectively. No marked changes in the standard biomarkers that regulate phosphate homeostasis were found. Serum αKlotho levels were associated with ΔeGFR. Multivariate regression analysis revealed that serum αKlotho levels significantly predicted a decrease in eGFR in the graft kidney 2 years after KTx, but serum 25(OH)D and FGF23 levels were not significant. Serum αKlotho levels showed an inverse correlation with fractional excretion of magnesium, which reflects tubular injury in the early stage of CKD. CONCLUSION: Measurement of serum αKlotho may serve as a useful predictor of KTx patients who require initiation of pre-emptive medication.


Asunto(s)
Biomarcadores/sangre , Glucuronidasa/sangre , Supervivencia de Injerto/fisiología , Trasplante de Riñón , Insuficiencia Renal/sangre , Adulto , Estudios Transversales , Progresión de la Enfermedad , Femenino , Factor-23 de Crecimiento de Fibroblastos , Humanos , Proteínas Klotho , Masculino , Persona de Mediana Edad
5.
AJNR Am J Neuroradiol ; 27(5): 1119-22, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16687555

RESUMEN

We performed time-resolved 3D phase-contrast MR imaging by using a 1.5T MR scanner to visualize hemodynamics in a silicon vascular model with a middle cerebral aneurysm. We ran an aqueous solution of glycerol as a flowing fluid with a pulsatile pump. Time-resolved images of 3D streamlines and 2D velocity vector fields clearly demonstrated that the aneurysm had 3D complex vortex flows within it during systolic phase. This technique provided us with time-resolved 3D hemodynamic information about the intracranial aneurysm.


Asunto(s)
Hemodinámica , Imagenología Tridimensional , Aneurisma Intracraneal/patología , Aneurisma Intracraneal/fisiopatología , Imagen por Resonancia Magnética , Modelos Anatómicos , Silicio , Anciano , Femenino , Humanos , Factores de Tiempo
6.
Int J Oral Maxillofac Surg ; 35(4): 356-61, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16288849

RESUMEN

Alteration in expression of E-cadherin and catenins is associated with loss of differentiation, acquisition of an invasive phenotype and poor clinical outcome in many types of cancer. To identify molecular prognostic markers, membrane expression levels of E-cadherin, and alpha-, beta- and gamma-catenin in biopsy samples (n=135) of oral squamous cell carcinoma (OSCC) were evaluated immunohistochemically in relation to preoperative tumour-related features, clinical course and prognostic value, and were found to be significantly correlated with an endophytic growth pattern and pathologically proved lymph-node metastasis. Alteration of expression of E-cadherin, and alpha-, beta- and gamma-catenin was also significantly correlated with poor disease-specific 5-year survival (P=0.0096, 0.0434, 0.0005 and 0.0005, respectively). Multivariate Cox proportional hazard regression analysis showed that alteration of beta- and gamma-catenin expression was a significantly independent prognostic parameter for survival (P=0.0112 and 0.0088, respectively), as was the case with endophytic growth pattern and advanced N-category. These results indicate that patients with OSCC and absent or reduced membrane expression of beta- and gamma-catenin should be considered a high-risk group for regional lymph-node metastasis and poor prognosis.


Asunto(s)
Carcinoma de Células Escamosas/metabolismo , Neoplasias de la Boca/metabolismo , Proteínas de Neoplasias/metabolismo , beta Catenina/metabolismo , gamma Catenina/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Biopsia , Métodos Epidemiológicos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico
7.
Biochim Biophys Acta ; 1311(3): 143-9, 1996 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-8664340

RESUMEN

A synthetic peptide corresponding to the N-terminal amino acid residues of stanniocalcin (STC1-20) and including a region that is known to be an active site in teleosts was prepared and tested for its effects on the metabolism of mammalian bone in vitro. STC1-20 (10(-10)-10(-12) M) inhibited increases in the number of tartrate-resistant acid phosphatase-positive, multinucleated cells promoted by an N-terminal fragment of human parathyroid hormone (hPTH1-34) in cultures of murine hemopoietic cells. STC1-20 also slightly decreased the rate of loss of radioactivity from calvariae of fetal rats that had been prelabeled with 45Ca, both with and without stimulation by hPTH1-34. The accumulation of cAMP induced by hPTH1-34 in ROS 17/2.8-5 cells was suppressed by STC1-20 (10(-10)-10(-12) M). Treatment with STC1-20 (10(-11)-10(-13) M) caused increases of the rate of incorporation of [3H]proline into the collagenase-digestible protein of calvariae in newborn mice. From these results, it appears that STC1-20 has diverse effects on the metabolism of mammalian bone, causing a biphasic response. Such effects have not been observed with intact stanniocalcin or with materials from the corpuscles of Stannius and they are also different from the effects of hPTH1-34.


Asunto(s)
Huesos/metabolismo , Calcio/metabolismo , Glicoproteínas/farmacología , Hormonas/farmacología , Fragmentos de Péptidos/farmacología , Fosfatasa Ácida/metabolismo , Secuencia de Aminoácidos , Animales , Sitios de Unión , Huesos/efectos de los fármacos , Recuento de Células/efectos de los fármacos , AMP Cíclico/metabolismo , Femenino , Glicoproteínas/química , Hormonas/química , Humanos , Isoenzimas/metabolismo , Ratones , Datos de Secuencia Molecular , Hormona Paratiroidea/farmacología , Fragmentos de Péptidos/síntesis química , Ratas , Ratas Sprague-Dawley , Salmón , Homología de Secuencia de Aminoácido , Cráneo , Fosfatasa Ácida Tartratorresistente , Teriparatido , Células Tumorales Cultivadas
8.
Biochim Biophys Acta ; 525(1): 194-9, 1978 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-150858

RESUMEN

The fibrinolytic activity of plasmin was determined by incubating with fibrin-fixed Blue Dextran as a substrate, the Blue Dextran released being proportional to the plasmin activity. The applicability of this method for rapid and accurate evaluation of fibrinolytic activity was demonstrated by dose-response curves with purified plasmin, plasmin generated by urokinase in human plasma and euglobulin. The method can also be used to determined plasmin inhibitors in plasma.


Asunto(s)
Fibrina/metabolismo , Fibrinolisina/análisis , Colorantes , Rojo Congo/metabolismo , Dextranos , Relación Dosis-Respuesta a Droga , Fibrinolisina/antagonistas & inhibidores , Guanidinas , Humanos , Azul de Metileno/metabolismo , Seroglobulinas/metabolismo , Activador de Plasminógeno de Tipo Uroquinasa/metabolismo
9.
J Am Coll Cardiol ; 36(6): 1847-52, 2000 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-11092655

RESUMEN

OBJECTIVES: We measured phospholipase C (PLC) activity in the cultured skin fibroblasts obtained from patients with and without coronary spasm and examined its correlation with coronary artery vasomotility. BACKGROUND: Coronary artery vasomotility is enhanced in coronary spastic angina (CSA), but no information is available for the intracellular signaling. In spontaneously hypertensive rats, PLC activity in the skin fibroblasts has been shown to be enhanced. METHODS: Skin fibroblasts obtained from 24 patients with CSA-14 with organic coronary artery disease (CAD) and 12 control subjects--were cultured by the explant method. Activity of PLC was determined by incubating the membrane fraction with 3H-phosphatidyl inositol bisphosphate and by quantifying 3H-inositol trisphosphate. In patients with CSA and control subjects, the relations between PLC activity and coronary artery basal tone and constrictor response to intracoronary acetylcholine (ACh) were examined. RESULTS: Activity of PLC (pmol/protein [mg] per min) was 1.74+/-0.19 in patients with CSA; 0.90+/-0.12 in patients with CAD; and 0.65+/-0.07 in control subjects (p<0.001, patients with CSA vs. patients with CAD and control subjects; p = NS, patients with CAD vs. control subjects). According to the Lineweaver-Burk plot, Michaelis constant (micromol/liter) of PLC was 28+/-4 in patients with CSA; 49+/-14 in patients with CAD; and 56+/-10 in control subjects (p<0.05, patients with CSA vs. control subjects), whereas the maximal velocity was not different between the three groups. There were significant positive correlations between PLC activity and both basal tone (p = 0.0108) and response to ACh (p = 0.0053). Western blot analysis using membrane fraction demonstrated that 89% of PLC isoenzymes detected was of the delta1 isoform. CONCLUSIONS: Because the PLC activity measured was genetically defined and was positively correlated with coronary artery vasomotility, enhanced PLC activity may be involved in the pathogenesis of coronary spasm.


Asunto(s)
Angina Pectoris Variable/fisiopatología , Vasos Coronarios/fisiopatología , Fibroblastos/metabolismo , Piel/citología , Fosfolipasas de Tipo C/metabolismo , Vasoconstricción , Angina Pectoris Variable/sangre , Células Cultivadas , Femenino , Humanos , Masculino , Persona de Mediana Edad
10.
Gene ; 249(1-2): 171-81, 2000 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-10831851

RESUMEN

The plant knotted1 (kn1)-like homeobox genes are known to play important roles in the maintenance of shoot apical meristem (SAM), determination of cell fate and differentiation of vegetative tissues. To study structural diversity of the three homologous loci encoding a KN1-like homeobox protein in the hexaploid wheat genome, we isolated clones from a cDNA library of young spikes of Japanese common wheat cultivar 'Norin 26'. Three different but highly homologous cDNAs were isolated and their sequences were determined. The mean homology of the deduced amino acid sequences was 96% as compared to the barley ortholog KNOX3. The wheat kn1-like homeobox proteins named WKNOX1 are encoded by a single set of homologous genes on the homologous group 4 chromosomes in the three component genomes of common wheat, i.e. 4A, 4B and 4D. The nucleotide sequence data and the Southern blot pattern suggested that the three homologous loci of wknox1 genes are highly conserved through polyploid evolution of wheat. They were expressed in SAM-containing shoots and young spikes but not in developed leaves, glumes and lemmas and callus tissues. The ectopic expression of the wknox1 was observed in lemma of wheat Hooded (Hd) mutants. The result suggested that the Hd gene is a dominant allele of the wknox1 locus on chromosome 4A.


Asunto(s)
ADN Complementario/genética , Proteínas de Homeodominio/genética , Proteínas de Plantas , Triticum/genética , Zea mays/genética , Secuencia de Aminoácidos , Secuencia de Bases , Southern Blotting , Mapeo Cromosómico , Clonación Molecular , ADN Complementario/química , ADN Complementario/aislamiento & purificación , ADN de Plantas/genética , Exones , Perfilación de la Expresión Génica , Genes Homeobox/genética , Genes de Plantas/genética , Intrones , Datos de Secuencia Molecular , Mutación , Filogenia , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , Poliploidía , Isoformas de Proteínas/genética , ARN de Planta/genética , ARN de Planta/metabolismo , Alineación de Secuencia , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico , Distribución Tisular
11.
Thromb Haemost ; 55(1): 24-30, 1986 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-3705005

RESUMEN

There has been no previous report indicating whether thrombin-like enzyme is contained in the venom of Trimeresurus flavoviridis which has the strongest toxic effect in the case of Habu bite. The present study was undertaken to clarify the existence of thrombin-like enzyme in Trimeresurus flavoviridis venom. As a starting material, lyophilized crude venom of Trimeresurus flavoviridis was used, and ammonium sulphate fractionation, gel filtration using Sephadex G-25, Sephadex G-150 and arginine-Sepharose affinity chromatography were carried out to separate and purify a thrombin-like enzyme from the crude venom. The enzyme was purified to a 137-fold increase in specific activity and the purified preparation revealed a single band on SDS-PAGE. The molecular weight of the enzyme was estimated to be 65,000-70,000 daltons by means of SDS-PAGE and gel filtration, and its isoelectric point was pH 4.5-5.5. Furthermore, the optimal pH of the enzyme was in the range of pH 8.0 to 8.5. Some of the differences in enzymatic properties between this enzyme and bovine thrombin were studied. The snake enzyme could coagulate only rabbit plasma and convert only purified rabbit fibrinogen to fibrin gel. In addition, this thrombin-like enzyme released only fibrinopeptide A from purified rabbit fibrinogen and did not release fibrinopeptide B.


Asunto(s)
Venenos de Crotálidos/análisis , Trombina/aislamiento & purificación , Animales , Cromatografía de Afinidad , Cromatografía en Gel , Fibrina/metabolismo , Fibrinógeno/metabolismo , Fibrinopéptido A/metabolismo , Calor , Técnicas In Vitro , Punto Isoeléctrico , Peso Molecular , Conejos , Especificidad de la Especie , Trombina/farmacología
12.
Thromb Haemost ; 42(2): 596-602, 1979 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-505366

RESUMEN

UK excretion rate in the diuretic state was investigated in human and animal studies. Loading of water, beer or diuretics in man decreased the UK excretion rate as urine flow increased. A linear relation between UK excretion rate and urine specific gravity was observed. Simultaneous loading of water and exercise suppressed the decrease in UK excretion rate and the increase in urine flow. In animal studies, a null value for UK excretion rate was observed as a result of giving physiological saline and/or furosemide, and a remarkable increase in urine flow was induced. These results clearly suggest the existence of a relation between renal function and UK excretion rate.


Asunto(s)
Diuresis , Endopeptidasas/orina , Activador de Plasminógeno de Tipo Uroquinasa/orina , Animales , Cerveza , Femenino , Furosemida/administración & dosificación , Humanos , Masculino , Esfuerzo Físico , Conejos , Cloruro de Sodio/administración & dosificación , Gravedad Específica , Agua
13.
Thromb Haemost ; 77(6): 1127-8, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9241744

RESUMEN

We reported previously that habutobin, a thrombin-like enzyme from Trimeresurus flavoviridis venom, clotted only rabbit fibrinogen, whereas human, monkey, bovine, dog, rat and guinea-pig fibrinogens were unaffected. In the present study, we investigated the cleavage site of the rabbit A alpha chain by habutobin. The fibrinopeptide released by habutobin was identical to the fibrinopeptide A released by thrombin, and its amino acid sequence corresponded to A alpha 1-16 of rabbit fibrinogen. It was clarified therefore that habutobin cleaves the Arg16-Gly17 bond in the A alpha chain of rabbit fibrinogen.


Asunto(s)
Fibrinógeno/efectos de los fármacos , Serina Endopeptidasas/farmacología , Secuencia de Aminoácidos , Animales , Arginina , Bovinos , Venenos de Crotálidos , Perros , Fibrinógeno/química , Glicina , Humanos , Datos de Secuencia Molecular , Conejos , Ratas
14.
Artículo en Inglés | MEDLINE | ID: mdl-9578151

RESUMEN

To assess the role of renal thromboxane in a salt sensitive pressor response in hypertension, urinary excretion of thromboxane and its release from isolated glomeruli and renal papillae were examined in deoxycorticosterone acetate treated rats with normal (0.6%, n = 12) and high (4%, n = 12) salt diets for 8 weeks. Mean blood pressure, measured directly by an implanted aortic catheter, was higher in the high salt diet group than in the normal salt diet group (146 +/- 2 vs 119 +/- 2 mmHg, P<0.01). Urinary excretion of thromboxane B2 and 6-keto-prostaglandin F1alpha in the high salt group were significantly higher than those in the normal salt diet group, but there was no difference in urinary excretion of prostaglandin E2 between the two groups. Release of thromboxane B2, 6-keto-prostaglandin F1alpha, and prostaglandin E2 from isolated glomeruli in the high salt diet group increased significantly by 104%, 55%, and 74%, respectively, compared with the normal salt diet group. Stepwise multiple linear regression analysis showed that significant contributory factors for mean blood pressure in deoxycorticosterone acetate treated rats were urinary excretion of sodium (F=14.187, P<0.01) and release of thromboxane B2 from isolated glomeruli (F=4.135, P<0.05). The unstandardized coefficient (R) calculated from the regression function using these two factors was 0.875 and R2 was 0.765. The manifest synthesis of thromboxane in renal glomeruli has an important role on salt sensitive pressor response in deoxycorticosterone acetate-salt hypertension of rats.


Asunto(s)
Presión Sanguínea/fisiología , Hipertensión/fisiopatología , Tromboxanos/fisiología , 6-Cetoprostaglandina F1 alfa/orina , Animales , Presión Sanguínea/efectos de los fármacos , Creatinina/sangre , Desoxicorticosterona , Dinoprostona/orina , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Frecuencia Cardíaca/fisiología , Hipertensión/inducido químicamente , Glomérulos Renales/química , Glomérulos Renales/fisiopatología , Médula Renal/química , Análisis Multivariante , Potasio/sangre , Prostaglandinas/orina , Ratas , Ratas Sprague-Dawley , Análisis de Regresión , Sodio/sangre , Sodio/orina , Cloruro de Sodio Dietético , Tromboxano B2/orina
15.
Brain Res ; 775(1-2): 183-8, 1997 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-9439841

RESUMEN

Positron emission tomography (PET) has been used in humans and in non-human primates to image and measure radioligand binding to neuroreceptors. The present study evaluated the feasibility of performing high-resolution PET experiments in a rodent model to measure receptor kinetics. The effects of acute and chronic administration of the opioid antagonist, nalmefene, on the binding activity of [11C]SCH23390 and [11C]N-methylspiperone at D1 and D2 dopamine receptors, respectively, was investigated in the rat. The interaction between central opioid and dopaminergic systems has been the focus of much attention due to their interactive role in mediating reinforcement and locomotor activity. In the present study, adult male Sprague-Dawley rats received either a single injection of 10 (mg/kg of nalmefene or control vehicle solution 1 h prior to the PET scan or were chronically administered 10 mg/kg/day of nalmefene or vehicle for 7 days by an osmotic minipump. Following acute administration of nalmefene, the binding potential of [11C]SCH23390 in the striatum was significantly increased. No changes in [11C]N-methylspiperone binding were found. Following chronic nalmefene administration, no significant change in either [11C]SCH23390 binding potential or [11C]N-methylspiperone binding was detected. These results suggest that nalmefene administration produces transient changes in the binding potential of D1-receptors in the striatum that are normalized after 1 week of steady-state administration.


Asunto(s)
Química Encefálica/efectos de los fármacos , Naltrexona/análogos & derivados , Antagonistas de Narcóticos/farmacología , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D2/metabolismo , Animales , Benzazepinas/metabolismo , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/metabolismo , Agonistas de Dopamina/metabolismo , Antagonistas de Dopamina/metabolismo , Masculino , Naltrexona/farmacología , Neostriado/efectos de los fármacos , Neostriado/metabolismo , Proyectos Piloto , Ratas , Ratas Sprague-Dawley , Receptores de Dopamina D1/efectos de los fármacos , Receptores de Dopamina D2/efectos de los fármacos , Espiperona/análogos & derivados , Espiperona/metabolismo , Tomografía Computarizada de Emisión
16.
Brain Res ; 706(2): 267-72, 1996 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-8822366

RESUMEN

To clarify the relationship between cerebral glucose metabolic rate constants and glucose-metabolizing enzyme activities in the cerebral cortex, we evaluated the cerebral metabolic rate of glucose (CMRGlu), metabolic rate constants of [18F]-2-fluoro-2-deoxy-D-glucose (FDG) and related enzyme activities in the frontal cortex under normal and glucose metabolism-suppressed conditions. Applying a three-compartment four-parameter model, metabolic rate constants were obtained by dynamic positron emission tomography with FDG, and CMRGlu was calculated based on these rate constants. The glycolytic enzyme activities were determined by in vitro biochemical assay. Three days after ibotenic acid injection into the basal forebrain, CMRGlu was decreased in the ibotenic acid-treated frontal cortex as well as k3* (phosphorylation), while K1* (plasma to brain) showed no remarkable change. No significant reductions of the enzyme activities except for hexokinase activity were found in the frontal cortex. Regression analysis showed a significant positive correlation between k3* and the hexokinase activity. These results suggested that k3* in the compartment analysis reflects hexokinase activity.


Asunto(s)
Lóbulo Frontal/metabolismo , Glucosa/metabolismo , Análisis de Varianza , Animales , Desoxiglucosa/análogos & derivados , Radioisótopos de Flúor , Fluorodesoxiglucosa F18 , Lóbulo Frontal/enzimología , Hexoquinasa/metabolismo , Cinética , Masculino , Ratas , Ratas Wistar , Análisis de Regresión , Tomografía Computarizada de Emisión
17.
Eur J Pharmacol ; 382(3): 187-96, 1999 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-10556669

RESUMEN

We examined the effects of enalapril and 4'-[(1, 4'-dimethyl-2'-propyl-[2,6'-bi-1H-enzimidazole]-1'-yl)methyl]-[1, 1'-biphenyl]-2-carboxylic acid (BIBR-277), an angiotensin II receptor antagonist, on contractile dysfunction in the stunned myocardium. Dogs were subjected to 20-min ligation of the coronary artery, followed by 60-min reperfusion. Saline, enalapril (1 mg/kg or 3 mg/kg), or BIBR-277 (3 mg/kg) was injected i.v. 10 min before ligation. D-Arginyl-L-arginlyl-L-prolyl-trans-4-hydroxy-L-prolylglycyl -3-(2-thi enyl)-L-alanyl-L-seryl-D-1,2,3, 4-tetrahydro-3-isoquinolinecarbonyl-L-(2alpha, 3beta, 7abeta)-octahydro-1H-indole-2-carbonyl-L-arginine (Hoe-140), a bradykinin B(2) receptor antagonist, at 300 microg/kg was injected i. v. 10 min before drug injection. Contractile function was assessed on the basis of percentage segment shortening (%SS). ATP levels were measured in 60-min reperfused hearts. %SS significantly decreased during ischemia, and recovered during reperfusion, although the %SS was significantly less than the pre-ischemic level. Both enalapril at either dose and BIBR-277 significantly enhanced %SS recovery during reperfusion, an effect which was associated with a tendency toward energy preservation. Hoe-140 completely abolished the effect of enalapril at either dose, while it did not modify that of BIBR-277. Inhibition of angiotensin II formation and bradykinin breakdown may be separately related to the improvement of myocardial stunning.


Asunto(s)
Angiotensina II/fisiología , Bradiquinina/fisiología , Contracción Miocárdica , Aturdimiento Miocárdico/metabolismo , Aturdimiento Miocárdico/fisiopatología , Adenosina Trifosfato/análisis , Anestesia , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Animales , Bencimidazoles/farmacología , Benzoatos/farmacología , Presión Sanguínea/efectos de los fármacos , Bradiquinina/análogos & derivados , Bradiquinina/farmacología , Antagonistas de los Receptores de Bradiquinina , Circulación Coronaria/efectos de los fármacos , Perros , Relación Dosis-Respuesta a Droga , Enalapril/farmacología , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Técnicas In Vitro , Ligadura , Masculino , Reperfusión Miocárdica , Telmisartán , Factores de Tiempo , Presión Ventricular/efectos de los fármacos
18.
Neurosci Lett ; 182(2): 279-82, 1994 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-7715827

RESUMEN

A system for the measurement of brain activity in conscious monkeys by positron emission tomography (PET) was established in the present study. The signal/noise ratio was maximal around 40 s for data acquisition in the PET scan with 15O-labeled water. When the monkey was stimulated by vibration and subtraction images of the data sets from regional cerebral blood flow (rCBF) changes in paired stimulation and control were superimposed on magnetic resonance images obtained from the same specimens, a somatotopic map corresponding to the sites stimulated was clearly demonstrated. Visual stimulation with a photic stimulator activated the corresponding regions of the primary visual cortex. Comparison of the activated sites and extents under the conscious state with those under anesthesia assured that the study is controllable; there was little unpredictable activation due to unlimited subject movement or to psychological effects.


Asunto(s)
Mapeo Encefálico/métodos , Procesamiento de Imagen Asistido por Computador , Tomografía Computarizada de Emisión , Animales , Velocidad del Flujo Sanguíneo , Pie , Mano , Haplorrinos , Imagen por Resonancia Magnética , Masculino , Corteza Visual
20.
J Hum Hypertens ; 14(1): 57-64, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10673733

RESUMEN

The morning surge in blood pressure (BP) is related to the morning occurrence of lethal cardiovascular events. We tested the hypothesis that salt intake may be associated with the morning surge in BP in essential hypertension. Seventy-six patients were admitted and placed on a low salt diet (2 g/day) for 7 days followed by a high salt diet (20-23 g/day) for another 7 days. At the end of each salt diet, 24-h ambulatory BP and heart rate monitorings and head-up tilt (HUT) test were performed. Patients whose average mean BP (MBP) was increased by more than 10% by salt loading were assigned to the salt-sensitive (SS) group (n = 37); the remaining patients, whose MBP was increased by less than 10%, were assigned to the non-salt-sensitive (NSS) group (n = 39). The increase in ambulatory MBP during 6.30-8.00 am above the baseline (2.00-4.00 am) was significantly enhanced by salt loading in the NSS group (P < 0.05), but not in the SS group. The coefficient of variation of 24-h MBP and heart rate was increased by salt loading only in the NSS group. The significant elevation of plasma noradrenaline concentration after awakening, which was noted during the low salt diet period, was unchanged during the high salt diet period in the NSS group, but abolished in the SS group. Salt loading enhanced HUT-induced decrease in systolic BP without affecting the heart rate response only in the NSS group. We conclude that the morning surge in BP is enhanced by salt loading in the NSS type of essential hyper- tension, presumably by the excessive activation of the sympathetic nervous system. Journal of Human Hypertension (2000) 14, 57-64.


Asunto(s)
Presión Sanguínea/efectos de los fármacos , Ritmo Circadiano/fisiología , Hipertensión/fisiopatología , Sodio en la Dieta/efectos adversos , 17-Hidroxicorticoesteroides/orina , 17-Cetosteroides/orina , Aldosterona/sangre , Barorreflejo/efectos de los fármacos , Monitoreo Ambulatorio de la Presión Arterial , Catecolaminas/metabolismo , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Hipertensión/sangre , Hipertensión/orina , Masculino , Persona de Mediana Edad , Renina/sangre , Sistema Nervioso Simpático/efectos de los fármacos , Sistema Nervioso Simpático/fisiopatología , Pruebas de Mesa Inclinada
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