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1.
Br J Cancer ; 93(6): 688-93, 2005 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-16136051

RESUMEN

The monoclonal antibody D2-40 is a specific lymphatic endothelial markers and D2-40 staining have been applicable to evaluate lymphatic invasion in various malignant neoplasms. In the present study, we investigated lymph node micrometastasis determined by immunohistochemistry (IHC) and reverse transcription-polymerase chain reaction (RT-PCR) in all dissected lymph nodes obtained from 80 patients with node-negative gastric cancer, and analysed the relationship between micrometastasis and clinicopathological findings including lymphatic invasion of the resected primary tumour using D2-40 immunohistochemical staining. The incidence of micrometastasis determined by IHC and RT-PCR was 11.3% (nine out of 80) and 31.3% (25 out of 80), respectively. Although haematoxylin-eosin (HE) staining revealed lymphatic invasion in 11.3% (nine out of 80) of patients, D2-40 staining uncovered new invasion in 23.8% (19 out of 80) of patients. In the diagnosis of HE and D2-40 staining, the incidence of micrometastasis was significantly higher in patients with lymphatic invasion than in those without lymphatic invasion (P=0.0150 and P<0.0001, respectively). Micrometastasis correlated more closely with D2-40 than with HE staining. We demonstrated a high incidence of micrometastasis and lymphatic invasion and a correlation between them even in pN0 gastric cancer. When planning less invasive treatment, the presence of such occult cancer cells should be considered.


Asunto(s)
Anticuerpos Monoclonales , Endotelio Linfático/inmunología , Ganglios Linfáticos/patología , Neoplasias Gástricas/secundario , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Técnicas para Inmunoenzimas , Metástasis Linfática , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Estadificación de Neoplasias , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Neoplasias Gástricas/inmunología
2.
Methods Find Exp Clin Pharmacol ; 24(4): 213-6, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-12092008

RESUMEN

In the present study, we examined the rates of urinary excretion of glucose and maltose after an infusion of maintenance fluid with glucose or maltose in adult rabbits. Three maintenance fluids (sugar-free, 5% glucose [Veen 3G] and 5% maltose [Actit]), which contained different sugars but were identical in electrolyte and acetate compositions and concentrations (Na: 45, K: 17, Mg: 5, Cl: 37, H2PO4: 10 and CH3COO: 20 mEq/l), were used in this study. In addition, the optimum infusion speed for maintenance therapy (10 ml/kg/h) was used. Animals were not given food or water during the 10-day period of administration. The body weights of the animals were measured every day. The concentrations of total protein, albumin, free fatty acids and glucose in the serum were measured. Urine samples for determination of glucose and maltose concentrations were collected from the 1st to 10th administrations. After infusion with 5% maltose, urinary maltose excretion decreased time-dependently, while that of glucose increased. This suggests that maltase activity time-dependently increases after infusion with maltose. In addition, total sugar was only minimally excreted into urine in the 5% glucose group compared with the 5% maltose group. Thus, the glucose infusion was superior to the maltose infusion in the rate of energy utilization. However, neither the loss of body weight nor the increase in concentration of free fatty acids in serum differed significantly among the 3 groups. In conclusion, infusion of maintenance fluid with 5% maltose results in the excretion of maltose and glucose into urine, since enzymatic hydrolysis of maltose to glucose is limited to that by maltase.


Asunto(s)
Glucosa/metabolismo , Maltosa/metabolismo , Análisis de Varianza , Animales , Fluidoterapia , Bombas de Infusión , Masculino , Maltosa/orina , Conejos
3.
Environ Sci Technol ; 35(1): 227-31, 2001 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-11352018

RESUMEN

ZnS nanocrystallites (nc-ZnS) prepared in N,N-dimethylformamide (DMF) photocatalyze dehalogenation of halogenated benzenes to benzene as the final product from chlorinated benzenes and to difluorobenzenes from fluorinated benzenes in the presence of triethylamine (TEA) as an electron donor under UV light irradiation (lambda > 300 nm). When CdS nanocrystallites (nc-CdS) are used as a photocatalyst (lambda > 400 nm), halogenated benzenes are photoreductively dehalogenated, yielding trichlorobenzene from hexachlorobenzene and tetrafluorobenzene isomers from hexafluorobenzene as the final products. Photoformed electrons on nc-ZnS and nc-CdS have such negative reduction potentials that these electrons reduce polyhalogenated benzenes, leading to the successive dehalogenation. nc-ZnS exhibits higher photocatalytic activitythan nc-CdS due to the more negative potential of the electrons on nc-ZnS than that on nc-CdS. The higher activities of nc-ZnS and nc-CdS compared to their bulk forms are explained as being due to their quantum size effects and the adsorptive interaction between the substrates and the nanosized photocatalysts.


Asunto(s)
Derivados del Benceno/química , Hidrocarburos Halogenados/química , Compuestos de Cadmio , Catálisis , Cristalización , Oxidación-Reducción , Fotoquímica , Sulfuros , Compuestos de Zinc
4.
Angew Chem Int Ed Engl ; 39(2): 357-360, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10649408

RESUMEN

Luminescence of Nd(III) in an organic solvent having C-H bonds was achieved for the first time by complexing Nd(III) with long-chain perfluoroalkylated ligands such as bis(perfluorooctylsulfonyl)aminate (pos). The complex [Nd(pos)(3)] gave an emission quantum yield of 3.0+/-0.5 % in undeuterated acetone. The bulky pos ligands suppress the excitation of C-H vibrations, energy migration at diffusional collision, and the coordination of acetone molecules (see picture) to the Nd(III) center, which otherwise quench the luminescence.

5.
Bioorg Med Chem Lett ; 9(2): 205-8, 1999 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-10021929

RESUMEN

The beta-cholestane derivatives 1a-c bearing a cascade-type polyol, were newly synthesized. The release of fluorescent marker 6-CF [5(6)-carboxyfluorescein] encapsulated in the modified liposomes prepared from 1 was dramatically faster than that in the conventional liposomes prepared from cholesterol.


Asunto(s)
Colestanos/sangre , Colestanos/síntesis química , Polímeros/química , Animales , Fluoresceínas/farmacología , Colorantes Fluorescentes/farmacología , Liposomas/química , Modelos Biológicos , Ratas , Factores de Tiempo
6.
Hum Cell ; 12(3): 131-8, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10695020

RESUMEN

The cell lines designated JHOS-2, JHOC-5 and JHOC-6 were established from epithelial ovarian carcinomas. JHOS-2 was established from a serous adenocarcinoma of a 45-year-old Japanese woman, JHOC-5 from a recurrent tumor of a clear cell adenocarcinoma of a 47-year-old Japanese woman and JHOC-6 from a tumor of a clear cell adenocarcinoma of a 43-year-old Japanese woman. These cell lines have grown well and serial passages were successively carried out more than 20 times. The monolayer cultured cells revealed neoplastic and pleomorphic features, and grew in multilayers. Electron micrographs revealed epithelial origins that had desmosomes and tonofilaments.


Asunto(s)
Adenocarcinoma de Células Claras/patología , Cistadenocarcinoma Seroso/patología , Neoplasias Ováricas/patología , Células Tumorales Cultivadas , Adenocarcinoma de Células Claras/ultraestructura , Adulto , Animales , Biomarcadores de Tumor/análisis , Antígeno Ca-125/análisis , Cistadenocarcinoma Seroso/ultraestructura , Femenino , Humanos , Cariotipificación , Ratones , Microscopía Electrónica , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Trasplante de Neoplasias , Neoplasias Ováricas/ultraestructura
7.
Radiat Med ; 16(2): 99-107, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9650896

RESUMEN

Eight subjects were examined both by abdominal X-ray computed transverse axial tomography (CT) and magnetic resonance imaging (MRI) (SE) (TR/TE, 200 ms/15 ms); another eight volunteers were subjected to three MRI scans to test the reliability of repeated measures. Correlations between fat area measures obtained by CT and by MRI for subcutaneous fat, total fat, and visceral vs. subcutaneous-fat ratio were highly significant (r = 0.93, 0.91, and 0.94, respectively; p < 0.01), and the standard errors of estimation were 9.99, 23.87, and 0.0047. The average errors of the method for different fat areas were 2.20 cm2 (intra-examination variance) and 3.75 cm2 (inter-examination variance) for visceral and 0.82 cm2 (intra-examination variance) and 1.29 cm2 (inter-examination variance) for subcutaneous fat areas, respectively. These results suggest that SE MRI is a practical approach to evaluate body fat distribution without the exposure to radiation. The reproducibility of SE MRI for the determination of fat areas is high; variation is small and acceptable. However, it is difficult to determine which estimate of fat area should be accepted when there is a discrepancy between MRI and CT measures.


Asunto(s)
Tejido Adiposo/patología , Imagen por Resonancia Magnética/métodos , Obesidad/diagnóstico , Radiografía Abdominal , Tomografía Computarizada por Rayos X/métodos , Tejido Adiposo/diagnóstico por imagen , Tejido Adiposo/metabolismo , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Obesidad/metabolismo , Reproducibilidad de los Resultados
8.
J Atheroscler Thromb ; 4(1): 34-9, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9583352

RESUMEN

Spin-echo magnetic resonance imaging (MRI) and postprocessing for fat quantification were used to examine the relationship of abdominal and thigh adipose-tissue distribution to serum lipids and glucose metabolism in obesity. Thirteen simple obese male patients and 12 non-obese male volunteers were examined by MRI, blood pressure, and fasting blood sample levels of serum lipids, glucose, immunoreactive insulin, c-peptide, HbA1C and hematocrit. Correlations of thigh visceral and subcutaneous fat areas to serum lipid levels were generally similar, but marked differences were found between relationships of thigh versus abdominal fat areas to serum lipid levels. In addition, diastolic blood pressure was significantly correlated with the fat area, especially with the abdominal visceral fat area (r=0.51, p<0.01), but not with abdominal subcutaneous fat area. The thigh muscle area was highly and inversely correlated with c-peptide (r=-0.72, p<0.01) and systolic blood pressure (r=-0.65). Differences in correlations between visceral and subcutaneous fat areas in the abdomen to metabolic parameters were found between abdominal visceral fat areas and HbA1C and between the abdominal subcutaneous fat areas and HbA1C. These findings suggest that the character of regional fat could be heterogeneous with respect to lipid and glucose metabolism and blood pressure levels in obese males.


Asunto(s)
Abdomen , Tejido Adiposo/diagnóstico por imagen , Glucemia/metabolismo , Lípidos/sangre , Obesidad/sangre , Muslo/diagnóstico por imagen , Adulto , Anciano , Presión Sanguínea , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Obesidad/fisiopatología , Radiografía
9.
Magn Reson Med ; 35(5): 640-7, 1996 May.
Artículo en Inglés | MEDLINE | ID: mdl-8722813

RESUMEN

Although Ca2+ transport regulation at subcellular organelles is of great interest, only limited methodology has been available for measuring organellar [Ca2+] levels. The present study employs the 19F NMR resonance frequency of 4F-BAPTA to measure free [Ca2+]. In 4F-BAPTA loaded perfused rabbit hearts, two 19F NMR resonances were clearly observed. The frequency of one was consistent with cytosolic [Ca2+] levels. Responses to agents that after sarcoplasmic reticulum function identified the other resonance as originating from that organelle. The experiments demonstrate the utility of NMR shift indicator methodology in obtaining simultaneous multi-compartment intracellular [Ca2+] measurements and in enabling organellar [Ca2+] measurements to be made from within intact living tissue.


Asunto(s)
Calcio/metabolismo , Espectroscopía de Resonancia Magnética , Miocardio/metabolismo , Animales , Transporte Biológico Activo , Citosol/metabolismo , Ácido Egtácico/análogos & derivados , Flúor , Corazón , Indicadores y Reactivos , Espectroscopía de Resonancia Magnética/métodos , Perfusión , Conejos , Retículo Sarcoplasmático/metabolismo
10.
Biomaterials ; 16(16): 1229-34, 1995 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8589192

RESUMEN

In vitro evaluation of antithrombogenicity of materials of artificial vascular vessels was carried out based on an analysis of the coagulation mechanism of blood. Coagulation of blood in tubes coated with endothelial cells (ECs) or segmented polyurethane (SPU) was measured by a rheological technique. Coagulation of blood in hybrid-type vascular vessel model tubes consisting of cultured ECs proliferated on carbon-deposited SPU was also examined. Coagulation of blood in these tubes occurred within 40 min, and appears to be due to the interaction between erythrocytes and a coagulant factor in plasma. From the in vitro evaluation test, when the time of onset of the coagulation of blood in contact with a surface of the artificial materials is longer than 20-39 min, the materials can be considered to provide an inert surface against thrombus formation and blood coagulation.


Asunto(s)
Materiales Biocompatibles , Coagulación Sanguínea/fisiología , Prótesis Vascular , Modelos Cardiovasculares , Trombosis/prevención & control , Adulto , Animales , Carbono , Bovinos , Células Cultivadas , Colágeno , Endotelio Vascular/citología , Hemorreología , Humanos , Técnicas In Vitro , Ensayo de Materiales , Adhesividad Plaquetaria , Poliuretanos
11.
Circ Res ; 77(4): 773-83, 1995 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7554125

RESUMEN

The postischemic generation of oxygen-derived free radicals may contribute to myocardial reperfusion injury by affecting sarcolemmal ion transport. Recent evidence indicates that exposure to reactive oxygen intermediates induces rapid increases in myocardial cytosolic free Ca2+ (Ca2+i). The mechanism is undetermined but may involve disturbances in Na+ homeostasis. We tested this hypothesis by interleaving 23Na and 31P nuclear magnetic resonance (NMR) measurements of Na+i and high-energy phosphates in glucose-perfused rat hearts exposed to hydroxyl radicals generated from H2O2 and Fe3+. In separate experiments, K+i and Ca2+i were measured with 39K and 19F NMR, respectively. The hearts rapidly exhibited contracture. Threefold Na+i increases and substantial K+i depletion were observed. Glycolytic inhibition was indicated by rapid sugar phosphate accumulation and cellular energy depletion. Notably, however, severe functional and energetic deterioration and substantial elevation of Ca2+i occurred before substantial Na+i accumulation or K+i depletion was observed. Further experiments investigated the ability of pyruvate to scavenge H2O2 and to protect the myocardium from oxidant stress. Pyruvate (1 or 2.5 mmol/L) dramatically attenuated functional and energetic alterations and alterations in Na+i and K+i, whereas acetate (2.5 mmol/L) offered no protection. Unlike pyruvate, lactate (5 mmol/L) has little or no capacity to scavenge H2O2 but has similar protective effects. In conclusion, pyruvate effectively protects against H2O2/Fe3+, largely by direct H2O2 scavenging. Protection with lactate may involve intracellular pyruvate augmentation. Without exogenous pyruvate or lactate, myocardial Na+ homeostasis can be substantially altered by oxidant stress, possibly via cellular energy depletion. Excess Na+i accumulation may, in turn, hasten metabolic and functional deterioration, but a causal link with the initial alterations in function or Ca2+i was not supported.


Asunto(s)
Metabolismo Energético/efectos de los fármacos , Corazón/fisiología , Transporte Iónico/efectos de los fármacos , Estrés Oxidativo , Animales , Lactatos/farmacología , Ácido Láctico , Espectroscopía de Resonancia Magnética , Masculino , Perfusión , Piruvatos/farmacología , Ratas , Ratas Sprague-Dawley
12.
Circ Res ; 77(2): 394-406, 1995 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7614723

RESUMEN

To clarify the role of Na+i, pHi, and high-energy phosphate (HEP) levels in the initiation and maintenance of ischemia-induced ventricular fibrillation (VF), interleaved 23Na and 31P nuclear magnetic resonance spectra were collected on perfused rat hearts during low-flow ischemia (51 minutes, 1.2 mL/g wet wt). When untreated, 50% of the hearts from normal (sham) rats and 89% of the hypertrophied hearts from aorticbanded (band) rats (P < .01 versus sham) exhibited VF. Phosphocreatine content was significantly higher in sham than band hearts during control perfusion (53.3 +/- 1.6 versus 39.8 +/- 2.0 mumol/g dry wt). Before VF at 20 minutes of ischemia, Na+i accumulation was greater in hearts that eventually developed VF than in hearts that did not develop VF for both band and sham groups (144% versus 128% of control in sham; P < .005) and was the strongest metabolic predictor of VF; ATP depletion was also greater for VF hearts in the sham group. Infusion of the Na(+)-H+ exchange inhibitor 5-(N,N-hexamethylene)-amiloride prevented VF in sham and band hearts; reduced Na+i accumulation but similar HEP depletion were observed compared with VF hearts before the onset of VF. Rapid changes in Na+i, pHi, and HEP began with VF, resulting in intracellular Na+i overload (approximately 300% of control) and increased HEP depletion. A delayed postischemic functional recovery occurred in VF hearts, which correlated temporally with the recovery of Na+i. In conclusion, alterations in Na+i were associated with spontaneous VF transitions, consistent with involvement of excess Na+i accumulation in VF initiation and maintenance and with previously reported alterations in Ca2+i with VF.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Metabolismo Energético , Espectroscopía de Resonancia Magnética , Isquemia Miocárdica/complicaciones , Sodio/metabolismo , Fibrilación Ventricular/metabolismo , Adenosina Trifosfato/metabolismo , Análisis de Varianza , Animales , Cardiomegalia/metabolismo , Técnicas In Vitro , Lactatos/metabolismo , Masculino , Isquemia Miocárdica/metabolismo , Perfusión , Fosfocreatina/metabolismo , Isótopos de Fósforo , Ratas , Ratas Sprague-Dawley , Isótopos de Sodio , Factores de Tiempo , Fibrilación Ventricular/etiología
13.
Jpn Heart J ; 35(4): 455-65, 1994 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7967050

RESUMEN

Isolated rat hearts were subjected to retrograde perfusion to investigate the protective effects of adenosine and verapamil on the myocardium. In group 1, the perfusate was standard Krebs-Henseleit buffer solution. The perfusate was changed to Krebs-Henseleit buffer containing verapamil (100 nM) in group 2, adenosine (100 microM) in group 3 and both drugs in combination in group 4 for 30 min before ischemia and during 20 min of reperfusion. Group 2 displayed a recovery of creatine phosphate but not of ATP at the end of reperfusion. In group 4, the recovery of both ATP and creatine phosphate was significantly greater than in group 1. The coronary flow of group 4 was significantly higher than that of the other groups. Treatment with both verapamil and adenosine before and after global ischemia may protect the ischemic myocardium by improving high energy phosphate metabolism and coronary circulation.


Asunto(s)
Adenosina/uso terapéutico , Isquemia Miocárdica/prevención & control , Daño por Reperfusión Miocárdica/prevención & control , Miocardio/metabolismo , Fosfatos/metabolismo , Verapamilo/uso terapéutico , Animales , Metabolismo Energético , Técnicas In Vitro , Espectroscopía de Resonancia Magnética , Masculino , Isquemia Miocárdica/metabolismo , Daño por Reperfusión Miocárdica/metabolismo , Ratas , Ratas Endogámicas WKY
14.
J Mol Cell Cardiol ; 26(2): 203-10, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8006981

RESUMEN

Changes in ATP and creatine phosphate levels during early (up to 150 s) global ischaemia were determined in isolated rat hearts by two chemical extraction methods (a conventional direct perchloric acid extraction and a stepwise extraction using alcohol and perchloric acid solutions) and by qualitative 31P-NMR. No difference in the ATP level hardly changed up to 40 s of ischaemia when measured by the three methods, and slightly decreased at 150 s of ischaemia. In contrast to ATP, creatine phosphate content in the normally perfused tissue was observed to be higher by the stepwise extraction (68-73 nmol/mg protein) than by direct perchloric acid extraction (55 nmol/mg protein). The creatine phosphate rapidly decreased to about 50% of normal value at 40 s of ischaemia, and the difference in the normal creatine phosphate content using the two chemical methods disappeared with the progression of ischaemia. Thus, the creatine phosphate more rapidly decreased when observed by the stepwise method than by the other two methods in this ischaemic condition. These results suggest that (1) creatine phosphate exists in an undetermined chemical state (perhaps neither in simple soluble form nor in so-called "bound" form) in rat cardiac myocytes, and (2) the stepwise extraction method is useful to measure the content of energy metabolites and to examine the intracellular chemical state in cardiac tissues.


Asunto(s)
Adenosina Trifosfato/análisis , Espectroscopía de Resonancia Magnética/métodos , Miocardio/química , Fosfocreatina/análisis , Animales , Enfermedad Coronaria/metabolismo , Etanol , Estudios de Evaluación como Asunto , Técnicas In Vitro , Masculino , Métodos , Percloratos , Perfusión , Fósforo , Ratas , Ratas Wistar
15.
Photochem Photobiol ; 58(5): 631-6, 1993 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8284317

RESUMEN

We have investigated the photosensitized monomerization of the cis,syn-cyclobutane dimer of 1,3-dimethylthymine using riboflavin tetraacetate and a 5-deazaflavin derivative as photosensitizer. Although little monomerization of the dimer is induced by photoexcitation of the flavins in the absence of any additives, the flavins can function as an efficient photosensitizer in the presence of magnesium perchlorate. Mechanistic studies involving spectroscopic, quantum-yield and flash-photolysis measurements demonstrated that the photosensitized monomerization exclusively proceeds through electron transfer from the dimer to the triplet flavins complexed with Mg2+. The effects of magnesium perchlorate are compared with those on the chloranil-photosensitized monomerization and also with the effects of HClO4 on the flavin-photosensitized reaction.


Asunto(s)
Flavinas/química , Compuestos de Magnesio/química , Percloratos/química , Fármacos Fotosensibilizantes/química , Dímeros de Pirimidina/efectos de la radiación , Timina/análogos & derivados , Modelos Químicos , Conformación Molecular , Dímeros de Pirimidina/química , Riboflavina/química , Timina/química , Timina/efectos de la radiación , Rayos Ultravioleta
16.
Jpn Circ J ; 56(3): 301-9, 1992 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1313119

RESUMEN

This study was designed to clarify the state of beta-adrenergic signal transduction and the disordered level of its transduction in hypertensive hearts, using myocardium from spontaneously hypertensive rats (SHR) as a generic model of essential hypertension. Beta-adrenergic receptor binding sites and dissociation constants in the extracted membranes of adult (70-100 days of age) SHR heart were not significantly different from those of Wistar-Kyoto (WKY) rats, the non-hypertensive control. The adenylate cyclase activities stimulated by isoproterenol with GTP, NaF and forskolin were significantly higher in SHR compared to those in WKY. To determine whether differences in signal transduction are natural or are a result of hypertension, we evaluated chronotropic responses in cultured cells of fetal hearts which had not been exposed to hypertension. Fetal cardiac muscle cells of SHR were more sensitive than WKY to isoproterenol stimulation over a wide concentration range. However, there were no statistically significant differences between these two strains with respect to the density of binding sites. These results suggest that in the transduction of adrenergic signals, alterations distal to the beta-receptors are present in the adult hearts of hypertensive rats, and, that the adrenergic signal transduction is already exaggerated in the pre-hypertensive fetal stage.


Asunto(s)
Adenilil Ciclasas/metabolismo , Hipertensión/enzimología , Miocardio/enzimología , Transducción de Señal , Animales , Sitios de Unión , Catecolaminas/análisis , Frecuencia Cardíaca/efectos de los fármacos , Técnicas In Vitro , Isoproterenol/farmacología , Ensayo de Unión Radioligante , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas WKY , Receptores Adrenérgicos beta/fisiología , ATPasa Intercambiadora de Sodio-Potasio/metabolismo
17.
Lancet ; 337(8745): 809-12, 1991 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-1672912

RESUMEN

To investigate the pathogenesis of acute coronary disorders and to clarify what type of plaque precedes these disorders, percutaneous transluminal coronary angioscopy, by means of a new angioscope, was carried out during catheterisation in 100 consecutive patients anatomically suitable for such investigations. The quality of the angioscopic image was good enough for analysis in 84 patients (14 with acute myocardial infarction [within 8 h of onset], 16 with recent myocardial infarction [3 days-2 months since onset], 24 with old myocardial infarctions, 10 with unstable angina, and 20 with stable angina). Thrombi were observed in most patients with acute coronary disorders (all 14 with acute myocardial infarction, 9 of 10 with unstable angina). Occlusive thrombi were more common in patients with acute myocardial infarction than in those with unstable angina (11 [79%] vs 1 [10%]; p less than 0.001), whereas mural (non-occlusive) thrombi were more common in the unstable angina than in the acute myocardial infarction group (8 [80%] vs 3 [21%]; p less than 0.001). Xanthomatous ulcerated plaques or ragged irregular surfaces were seen in patients with acute coronary disorders and in those with recent myocardial infarction. Xanthomatous plaques were more common in patients with acute coronary disorders (50%) than in those with stable angina (15%) or old myocardial infarction (8%). By contrast white and smooth plaques were seen in cases of stable angina and old myocardial infarction. Angioscopy could display the intracoronary lumen more precisely than could coronary arteriography. This angioscopic study suggested that, although a thrombus overlying a rupture in the lining of the plaque was common in both unstable angina and acute myocardial infarction, the character of the thrombus may differ between these disorders, and lipid-rich xanthomatous plaque may precede rupture.


Asunto(s)
Angina de Pecho/patología , Enfermedad de la Arteria Coronaria/patología , Endoscopía/métodos , Infarto del Miocardio/patología , Enfermedad Aguda , Adulto , Anciano , Angina de Pecho/diagnóstico por imagen , Angina de Pecho/etiología , Angina Inestable/diagnóstico por imagen , Angina Inestable/patología , Cateterismo Cardíaco/métodos , Color , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/etiología , Trombosis Coronaria/diagnóstico por imagen , Trombosis Coronaria/etiología , Trombosis Coronaria/patología , Estudios de Evaluación como Asunto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/diagnóstico por imagen , Infarto del Miocardio/etiología , Radiografía
18.
Anal Biochem ; 192(1): 117-24, 1991 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1646573

RESUMEN

To compare the extractability of creatine phosphate with that of ATP by alcohol extraction, both compounds were extracted from normal perfused rat heart tissues by using various stepwise concentrations of ethanol and 0.4 M HClO4. Powdered samples (6-15 mg wet wt) from the freeze-clamped tissues were homogenized in 2 ml of the ethanol solutions. After centrifugation, the supernatant was removed; each centrifuged sediment was rehomogenized with 2 ml of 0.4 M HClO4 and centrifuged. The supernatant was neutralized with 0.4 m KHCO3. The same powdered samples were directly homogenized with 2 ml of 0.4 M HClO4 and treated in the same manner. Only a small amount of ATP in the tissues was extracted by an 85% or higher concentration of ethanol. Further, about 13% of the tissue ATP was not extractable by the subsequent perchloric acid extraction. In contrast to ATP, creatine phosphate in the tissues was partially extracted by 95% ethanol and nearly all of the tissue creatine phosphate was extracted by 70% ethanol. The total creatine phosphate obtained by 70% ethanol and by subsequent perchloric acid extraction was significantly higher than that obtained by direct perchloric acid extraction. From these results, it was concluded that the extractability of creatine phosphate in the tissue by alcohol extraction is clearly different from that of ATP. Additionally, the stepwise extraction is recommended as a useful method for the extraction of energy metabolites in perfused rat heart tissue.


Asunto(s)
Adenosina Trifosfato/aislamiento & purificación , Etanol , Miocardio/química , Percloratos , Fosfocreatina/aislamiento & purificación , Animales , Espectroscopía de Resonancia Magnética , Masculino , Peso Molecular , Músculos/química , Radioisótopos de Fósforo , Ratas , Ratas Endogámicas , Soluciones
19.
Photochem Photobiol ; 52(5): 973-9, 1990 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1962858

RESUMEN

The photosensitized monomerization of the cyclobutane dimers of 1,3-dimethylthymine by p-chloranil was investigated by means of steady-state irradiation and laser-flash photolysis. Quantum yields for the monomerization are 0.34 for the cis,syn dimer, 0.39 for the trans,syn dimer, and much less than 10(-2) for the cis,anti isomer. Formation of the chloranil anion radical associated with quenching of triplet chloranil by the dimers demonstrates that electron transfer from dimers to triplet chloranil occurs to initiate the monomerization. Kinetic analysis suggested that the syn-dimer cation radicals undergo the ring cleavage at greater than or equal to 10(9) s-1 before escaping from the solvent cage, while the reactivity of the anti-dimer cation radical is very low. The different reactivities of the syn and anti dimer cation radicals are discussed in terms of through-bond coupling between the n orbitals of N(1) and N(1') involving the cyclobutane-ring sigma orbitals. In the cases of the syn-dimers, the sensitizer-dimer ion-radical pairs undergo the rapid geminate recombination that works as a major energy dissipating channel responsible for the lower-than-unity quantum yields. It has been found that the presence of Mg(ClO4)2 at 0.1 M enhances approximately 1.5 times either the monomerization of the syn dimers or the formation of the chloranil anion radical. A laser-flash photolysis study shows that Mg2+ forms a complex with either the triplet or the anion radical of chloranil. The net salt effects are attributed to the retardation of the rapid geminate recombination by the participation of Mg2+ in the sensitizer-dimer ion-radical pairs.


Asunto(s)
Cloranilo/química , Compuestos de Magnesio , Magnesio , Percloratos , Dímeros de Pirimidina/efectos de la radiación , Rayos Láser , Estructura Molecular , Fotólisis , Teoría Cuántica
20.
J Cardiol ; 20(3): 571-81, 1990.
Artículo en Japonés | MEDLINE | ID: mdl-2131347

RESUMEN

To diagnose and characterize post-infarction left ventricular aneurysms, we performed exercise thallium-201 myocardial single photon emission computed tomography (SPECT) combined with selective coronary angiography and left ventriculography. The subjects consisted of 79 patients with acute myocardial infarction; 42 with anteroseptal, three with both anterior and inferior, 29 with inferior and five with posterior infarction. Visual classification of ventricular wall morphology by either a horizontal or a vertical long-axis image was designed into convergent (C), parallel (P) and divergent (D) types, according to the interrelationship between either septal and lateral wall or anterior and inferior wall, respectively. This method was applied in post-stress and delayed images, and these patients were divided into five groups (Group A-E) in accordance with varying morphological types from the post-stress to the delayed as follows: C-C (Group A, 36 patients), P-C (Group B, 8), P-P (Group C, 7), D-P (Group D, 5) and D-D (Group E, 23). A high incidence (21/23) of a left ventricular aneurysm by left ventriculography was recognized in Group E patients in comparison with other Groups. Provided that either Group D or E (all patients had anterior infarction) had left ventricular aneurysms, the diagnostic sensitivity, specificity and accuracy were 89%, 92% and 86%, respectively. Two of three patients with false negative diagnosis had only apical involvement. Furthermore, these two Groups had significantly larger defect scores as calculated by polar maps than did the other three Groups. When patients with anterior infarction with defect scores of 200 or greater were defined positive, the sensitivity, specificity and accuracy of ventricular aneurysms were 96%, 75% and 86%, respectively. One false negative case was apical infarction, and one of the two false positive cases were extensive anteroseptal infarction involving the apex. These results suggest that a left ventricular aneurysm which is important in predicting prognostic sequence could be diagnosed only by exercise SPECT, and that it could be characterized by extensive and severe apicoanterior infarction and a divergent-type ventricular wall arrangement on a post-stress SPECT image.


Asunto(s)
Aneurisma Cardíaco/diagnóstico por imagen , Corazón/diagnóstico por imagen , Radioisótopos de Talio , Tomografía Computarizada de Emisión de Fotón Único , Prueba de Esfuerzo , Aneurisma Cardíaco/etiología , Ventrículos Cardíacos , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/complicaciones
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