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1.
Heart Vessels ; 38(1): 96-105, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35871206

RESUMEN

No predictive clinical risk scores for net adverse clinical events (NACE) have been developed for patients with atrial fibrillation (AF) after percutaneous coronary intervention (PCI). We evaluated NACE to develop clinically applicable risk-stratification scores in the Bleeding and thrombotic risk evaluation In patients With Atrial fibrillation under COronary intervention (BIWACO) study, a multicenter survey which has enrolled a total of 7837 patients. We also investigated the current status and time trends for the use of antithrombotic drugs. A total of 188 AF patients who had received PCI were examined. At discharge, 65% of patients were prescribed a triple therapy (TT), 6% were prescribed a dual therapy, the remaining 29% of patients received dual-antiplatelet therapy. After 4 years, the fraction of patients continuing TT decreased by 15%, whereas oral anticoagulant alone was only 2% of patients. NACE developed in 20% of patients, resulting in death in 5% of the patients, and the remaining 13% experienced bleeding events. We developed risk scores for NACE comprising the five strongest predictive items, which we designated BIWACO scores. The area under the curve was 0.774 for NACE. Our study explored the differences in treatment practices and guideline recommendations for antithrombotic therapy. We concluded that our BIWACO score is useful for predicting clinical outcomes in AF-patients after PCI.


Asunto(s)
Fibrilación Atrial , Intervención Coronaria Percutánea , Humanos , Fibrilación Atrial/complicaciones , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/terapia , Inhibidores de Agregación Plaquetaria/efectos adversos , Intervención Coronaria Percutánea/efectos adversos , Intervención Coronaria Percutánea/métodos , Anticoagulantes , Hemorragia/inducido químicamente , Fibrinolíticos/efectos adversos , Quimioterapia Combinada
2.
Eur Heart J Case Rep ; 5(2): ytaa538, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33598617

RESUMEN

BACKGROUND: Anderson-Fabry disease (AFD) is an X-linked lysosomal storage disorder resulting from a mutation of alpha-galactosidase A gene (GLA), causing deficiency in alpha-galactosidase activity. The enzyme deficit can lead to storage of globotriaosylceramide in various organs including heart. Studies suggest that vasospastic angina (VSA) is associated with AFD. CASE SUMMARY: This clinical case series aimed to present two female patients with AFD, including progressive cardiac involvement: a 50-year-old woman (patient number 1) and a 39-year-old woman (patient number 2) who are siblings with a male AFD patient harbouring p. Arg342Glu missense variant in alpha-galactosidase A gene (GLA), who suffered VSA and subsequent ventricular fibrillation. Enzymatic tests and genetic analysis confirmed AFD in both female patients and histological tests revealed globotriaosylceramide deposits in their hearts. In patient number 1, a 12-lead electrocardiography and transthoracic echocardiography revealed cardiac hypertrophy. Coronary angiography revealed no organic coronary artery stenosis and vasospasms was induced by spasm provocation test. In patient number 2, no signs of cardiac hypertrophy were found, and coronary arteries had no organic stenosis with negative spasm provocation test. Both patients received enalapril therapy and enzyme replacement therapy (ERT). DISCUSSION: Different phenotype of AFD was occurred even with the same genetic variant in female heterozygote patients. The duration of exposing accumulation of Gb3 might affect cardiac hypertrophy and vasospasms. Coronary angiography with acetylcholine provocation test should be considered in female AFD patient, especially in case with cardiac hypertrophy.

3.
Acta Cardiol ; 65(4): 449-56, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20821938

RESUMEN

OBJECTIVE: D-dimer and von Willebrand factor (vWF) are associated with atherosclerosis. We recently reported that in a post-World War II birth cohort, Japanese men in Japan had lower levels of atherosclerosis than white men in the United States (U.S.). We examined whether the differences in D-dimer and vWF levels are associated with differences in atherosclerosis between the two populations. METHODS AND RESULTS: Population-based samples of 99 Japanese and 100 white American men aged 40-49 years were examined for coronary artery calcification (CAC), carotid intima-media thickness (IMT), D-dimer, vWF, and other factors using a standardized protocol. When compared to white American men,Japanese had similar levels of D-dimer (0.22 +/- 0.28 vs. 0.19 +/- 0.24 microg/L, respectively, P = 0.39) but significantly higher levels of vWF (124.1 +/- 36.6 vs. 91.3 +/- 48.8%, respectively, P < 0.01). Japanese as compared to white American men had significantly lower prevalence of CAC (13.1 vs. 28.0%, P < 0.01, respectively) and significantly lower IMT (0.61 +/- 0.07 vs. 0.66 +/- 0.08 mm, P < 0.01, respectively). Japanese men had a significant positive association of D-dimer with the prevalence of CAC and a negative association of vWF with IMT, whereas white American men did not have any significant associations. CONCLUSIONS: In men aged 40-49 years, Japanese as compared to white Americans had similar levels of D-dimer and higher levels of vWF although Japanese had a significantly lower prevalence of CAC and IMT. These haemostatic factors are unlikely to explain the difference in atherosclerosis in these populations.


Asunto(s)
Aterosclerosis/sangre , Aterosclerosis/etnología , Productos de Degradación de Fibrina-Fibrinógeno/metabolismo , Factor de von Willebrand/metabolismo , Adulto , Antropometría , Aterosclerosis/epidemiología , Aterosclerosis/patología , Distribución de Chi-Cuadrado , Estudios Transversales , Humanos , Japón/epidemiología , Modelos Lineales , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Encuestas y Cuestionarios , Túnica Íntima/patología , Estados Unidos/epidemiología
4.
Eur Heart J Case Rep ; 3(4): 1-5, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32123796

RESUMEN

BACKGROUND: Fabry disease (FD) is an X-linked lysosomal storage disorder resulting from a deficiency in alpha-galactosidase A. The major causes of death due to cardiac complications include life-threatening arrhythmias. In addition, life-threatening arrhythmias may be related to myocardial fibrosis assessed by late gadolinium enhancement (LGE). CASE SUMMARY: A 43-year-old man with sinus bradycardia and left ventricular hypertrophy was referred to our cardiology department. Family history includes unexplained hypertrophy and sick sinus syndrome in mother. Additionally, his plasma alpha-galactosidase A activity was low. He was subsequently diagnosed with FD. Enzyme replacement therapy using 1.0 mg/kg agalsidase-ß was initiated. During the fifth administration, he developed ventricular fibrillation (VF). Electrocardiography conducted immediately before VF revealed ST elevation in the inferior leads with reciprocated ST depression. Cardiac magnetic resonance imaging showed no LGE in the myocardium. Coronary angiography showed no organic stenosis; moreover, coronary spasms were induced by an intracoronary acetylcholine injection. Ventricular fibrillation was not observed as the patient received calcium antagonists. DISCUSSION: This report suggests that vasospastic angina pectoris is associated with life-threatening arrhythmias in patient with FD without LGE.

5.
Ann Epidemiol ; 18(4): 310-5, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17983767

RESUMEN

PURPOSE: Koreans are recently at higher risk for coronary heart disease than are the Japanese. We aimed to evaluate levels of carotid intima-media thickness (IMT) and coronary risk factors in Korean and Japanese men in the post-World War II birth cohort. METHODS: We conducted a population-based study of 352 randomly selected healthy men 40 to 49 years of age: 102 Koreans in Ansan City, Gyeonggi-do, Korea and 250 Japanese in Kusatsu City, Shiga, Japan. Imaging carotid IMT by ultrasonography and other procedures were standardized. Analyzing blood samples and reading carotid IMT were performed at the University of Pittsburgh. RESULTS: Despite more favorable or similar features in coronary risk factors as compared to Japanese men, the Korean men had a higher crude IMT level than the Japanese men (mean +/- standard error, 0.655+/-0.008 mm vs 0.616+/-0.005 mm, respectively, p<0.0001). The difference in the levels of carotid IMT significantly remained after adjusting for metabolic and conventional risk factors (0.654+/-0.008 mm vs. 0.616+/-0.005 mm, respectively; p<0.0001). CONCLUSIONS: Among men 40 to 49 years of age, Koreans had significantly higher levels of carotid IMT than the Japanese. Factors that underlie the different susceptibility to subclinical atherosclerosis need to be explored.


Asunto(s)
Arterias Carótidas/anatomía & histología , Túnica Íntima/anatomía & histología , Adulto , Aterosclerosis/epidemiología , Aterosclerosis/patología , Arterias Carótidas/diagnóstico por imagen , Arterias Carótidas/patología , Enfermedades de las Arterias Carótidas , Estudios de Cohortes , Enfermedad Coronaria/epidemiología , Humanos , Japón , Corea (Geográfico) , Masculino , Persona de Mediana Edad , Factores de Riesgo , Túnica Íntima/patología , Ultrasonografía
6.
Metabolism ; 57(2): 177-82, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18191046

RESUMEN

In men in the post-World War II birth cohort, that is, men aged 40 to 49 years, whites in the United States had significantly higher levels of intima-media thickness of the carotid arteries (IMT) than the Japanese in Japan (Electron-Beam Tomography and Risk Assessment Among Japanese and US Men in the Post World War II Birth Cohort [ERA JUMP] study). The difference remained after adjusting for traditional risk factors. Primary genetic effects are unlikely, given the degree to which IMT is increased in the Japanese who migrated to the United States. We investigated whether the differences in the distributions of lipoprotein subclasses explain the difference in IMT between the 2 populations. We examined population-based samples of 466 randomly selected men aged 40 to 49 years (215 whites from Allegheny County, Pennsylvania, and 241 Japanese from Kusatsu, Shiga, Japan). Lipoprotein subclasses were determined by nuclear magnetic resonance (NMR) spectroscopy. The whites had significantly higher levels of large very low-density lipoprotein particles and significantly lower levels of large high-density lipoprotein particles than the Japanese, whereas the 2 populations had similar levels of small low-density lipoprotein particles. The 2 populations had similar associations of IMT with NMR lipoproteins. Adjusting for NMR lipoproteins did not attenuate the significant difference in IMT between the 2 populations (0.671 +/- 0.006 mm for the whites and 0.618 +/- 0.006 mm for the Japanese, P = .01, mean +/- SE). Differences in the distributions of NMR lipoproteins between the 2 populations did not explain the higher IMT in the whites.


Asunto(s)
Pueblo Asiatico , Arteria Carótida Común/metabolismo , Lipoproteínas HDL/sangre , Lipoproteínas LDL/sangre , Lipoproteínas VLDL/sangre , Túnica Íntima/metabolismo , Población Blanca , Adulto , Proteína C-Reactiva/metabolismo , Humanos , Japón , Modelos Lineales , Masculino , Persona de Mediana Edad , Análisis Multivariante , Pennsylvania , Triglicéridos/sangre
7.
Metabolism ; 56(8): 1060-4, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17618950

RESUMEN

To investigate the association between fish consumption and early atherosclerosis, we analyzed the relationship between fish consumption and average intima-media thickness (AveIMT) by carotid ultrasound in middle-aged Japanese men. Participants were 250 randomly selected, community-based Japanese men aged 40 to 49 years without a prior history of cardiovascular disease. AveIMT was calculated from the mean of 1-cm lengths of both the right and the left carotid arteries at 8 locations. A lifestyle survey was carried out using a self-administered questionnaire including the frequency of fish intake. There were 147 men in the fewer than 4 times per week fish consumption group and 103 men in the 4 or more times per week group. The mean AveIMT was significantly higher in the low fish consumption group than in the high fish consumption group (0.623+/-0.068 vs 0.605+/-0.065 mm, P=.03). After adjustment for age, waist circumference, pack-years of smoking, alcohol consumption, diabetes, and lipid-lowering medications, the significant difference in the AveIMT between the 2 groups remained. However, after further adjustment for low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides, and C-reactive protein in the model, the significant difference disappeared. Fish consumption may be protective against early atherosclerosis in middle-aged men, probably through its beneficial effects on inflammation.


Asunto(s)
Aterosclerosis/epidemiología , Dieta , Peces , Carne , Adulto , Envejecimiento/fisiología , Consumo de Bebidas Alcohólicas , Animales , Arterias Carótidas/diagnóstico por imagen , Colesterol/sangre , Diabetes Mellitus/sangre , Diabetes Mellitus/fisiopatología , Humanos , Hipolipemiantes/uso terapéutico , Japón/epidemiología , Masculino , Persona de Mediana Edad , Fumar , Ultrasonografía , Relación Cintura-Cadera
8.
Int J Epidemiol ; 34(1): 173-9, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15563587

RESUMEN

BACKGROUND: Since World War II (WWII), exposures to westernized lifestyle have occurred in many non-Western countries, including Japan. National surveys showed that risk factor profiles for atherosclerosis around 1990 were similar in men in the post WWII birth cohorts in the US and Japan. We compared the degree of coronary calcium and other factors in men in the post WWII birth cohort: men aged 40-49 in the US and Japan. METHODS: We conducted a cross-sectional study examining randomly selected 100 men from Kusatsu, Japan, and 100 men from Allegheny County, US. Coronary calcium was assessed using electron-beam computed tomography. RESULTS: Systolic blood pressure, total cholesterol, low density lipoprotein (LDL)-cholesterol, and smoking rates were higher among the Japanese (122.6 +/- 14.1 versus 113.7 +/- 9.6 mmHg, P < 0.01; 5.72 +/- 0.90 versus 4.99 +/- 0.81 mmol/l (220.9 +/- 34.6 versus 192.8 +/- 31.3 mg/dl), P < 0.01; 3.52 +/- 1.01 versus 3.10 +/- 0.78 mmol/l (136.0 +/- 39.0 versus 119.7 +/- 30.0 mg/dl), P < 0.01; and 48 versus 15%, P < 0.01, respectively). Triglycerides and fibrinogen were similar. High density lipoprotein (HDL)-cholesterol was higher among the Japanese. Body mass index, fasting insulin, and C-reactive protein were higher among the Americans. Prevalence of coronary artery calcium score >0 was strikingly lower among the Japanese than the Americans (13% versus 47%, P < 0.01). CONCLUSIONS: Much lower prevalence of coronary calcium despite a less favourable profile of many major independent risk factors in the Japanese might imply that there are strong protective factors against atherosclerosis in the Japanese. Further investigation is of critical importance.


Asunto(s)
Calcinosis/etnología , Enfermedad Coronaria/etnología , Adulto , Calcinosis/diagnóstico por imagen , Calcinosis/etiología , Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/etnología , Enfermedad de la Arteria Coronaria/etiología , Enfermedad Coronaria/diagnóstico por imagen , Enfermedad Coronaria/etiología , Humanos , Japón/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Tomografía Computarizada por Rayos X , Estados Unidos/epidemiología
9.
Atherosclerosis ; 164(1): 171-7, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12119207

RESUMEN

UNLABELLED: Moderate drinkers with a defective alcohol dehydrogenase type 3 (ADH3) genotype have higher high-density lipoprotein (HDL) levels and a decreased risk of coronary artery disease (CAD). We examined the interaction between the aldehyde dehydrogenase type 2 (ALDH2), alcohol intake, and HDL levels in 826 men and 1295 women in a rural town in Japan. The ALDH2 genotype of each subject was determined by polymerase chain reaction (PCR) analysis. HDL was adjusted for the alcohol intake, age, body mass index, smoking status, total cholesterol, triglycerides and HbA1c levels. None of the subjects had a history or ECG suggestive of CAD. The proportions of ALDH2, *1/*1, *1/*2, and *2/*2 (defective homozygote) were 45.8, 46.0, and 8.2%, respectively, for men. Drinking more than two drinks daily was associated with lower HDL levels in men with the defective genotypes compared with men with a normal genotype (55.6+/-0.9 vs. 51.2+/-0.9 mg/dl, mean+/-S.E., P<0.0001). Also, drinking more than 0.5 drinks daily was not associated with beneficial effects on HDL levels in women with defective ALDH2 genotypes. CONCLUSIONS: Alcohol intake did not have beneficial effects on HDL levels in the defective ALDH2 genotype and may not protect against CAD in subjects with defective ALDH2 genotypes.


Asunto(s)
Consumo de Bebidas Alcohólicas/sangre , Aldehído Deshidrogenasa/genética , HDL-Colesterol/sangre , Colesterol/sangre , Adulto , Anciano , Aldehído Deshidrogenasa/metabolismo , Aldehído Deshidrogenasa Mitocondrial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo Genético
10.
J Am Soc Echocardiogr ; 15(10 Pt 1): 1074-9, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12373249

RESUMEN

The aim of this study was to evaluate whether coronary flow velocity (CFV) and coronary flow velocity reserve (CFVR) in the posterior descending right coronary artery can be reliably measured by transthoracic Doppler echocardiography (TTDE). In 17 patients, CFV in the posterior descending right coronary artery was measured with TTDE at the time of Doppler guidewire examination. CFV was measured by both methods at baseline and under hyperemic conditions. TTDE data were obtained for 12 patients. CFV and CFVR by TTDE show a good correlation with those obtained by the Doppler guidewire method (average diastolic peak velocity: r = 0.98, y = 0.85x + 5.26; diastolic peak velocity: r = 0.97, y = 0.94x + 3.39; CFVR: r = 0.97, y = 0.87x + 0.56). CFV and CFVR in the posterior descending right coronary artery obtained noninvasively by TTDE accurately reflect these values obtained by the invasive Doppler guidewire method.


Asunto(s)
Velocidad del Flujo Sanguíneo/fisiología , Circulación Coronaria/fisiología , Vasos Coronarios/diagnóstico por imagen , Ecocardiografía Doppler/instrumentación , Anciano , Vasos Coronarios/fisiología , Ecocardiografía/instrumentación , Ecocardiografía/métodos , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador
11.
Bioresour Technol ; 142: 535-9, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23765004

RESUMEN

The mechanism of the increase in the hydrolysis rate and yield by the addition of Tween 80 to the hydrolysis reaction of filter paper was investigated under static and agitated conditions. The increase in the hydrolysis rate by addition of Tween 80 was observed under the agitated condition only. The effects of Tween 80 on the changes in the protein concentration of individual cellulase components were investigated in the absence of substrates. Agitation of the enzyme solution resulted in the drastic decrease of SDS-PAGE bands intensity of CBH2 (cellobiohydrolase 2). The addition of Tween 80 prevented this. Thus, the Tween 80 functions to stabilize instable cellulase components under the agitated condition. Moreover, addition of Tween 80 completely suppressed the decrease of CBH2 intensity by agitation at 30°C. Results suggest that Tween 80 stabilizes instable cellulase components not only during hydrolysis, but during enzyme production also.


Asunto(s)
Celulasa/metabolismo , Polisorbatos/química , Electroforesis en Gel de Poliacrilamida , Estabilidad de Enzimas , Hidrólisis , Papel , Especificidad por Sustrato
12.
Bioresour Technol ; 121: 154-60, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22858480

RESUMEN

The effect of enzyme loading under static and agitated conditions was investigated. Enzymatic hydrolysis of 10 w/v% de-lignified cellulose slurry such as filter paper, avicel and pulp was conducted under agitated (120 rpm) and static condition, and the enzyme loading ranging from 1.2 to 120 mg-protein/g-dry substrate. Under the agitated condition, the final sugar concentration decreased with the decreasing enzyme loading. Under the static condition, the final sugar concentration was maintained even if the enzyme loading was decreased. The above phenomenon was caused by a rapid precipitation of cellobiohydrolase 2 (CBH2) under the agitated condition, which was not observed under the static condition. The hydrolysis experiments using enzymes containing different ratios of cellobiohydrolase 1 (CBH1) and CBH2 under the static condition suggested that preservation of CBH2 and its synergism with CBH1 is essential for static condition's characteristics, and for efficient hydrolysis of cellulose.


Asunto(s)
Biocombustibles , Celulosa 1,4-beta-Celobiosidasa/metabolismo , Celulosa/metabolismo , Glucosa/biosíntesis , Cromatografía Líquida de Alta Presión , Electroforesis en Gel de Poliacrilamida , Hidrólisis
13.
J Am Chem Soc ; 124(42): 12428-9, 2002 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-12381181

RESUMEN

An unprecedented clean interconversion between a novel bis(mu-thiolato)dicopper(II) complex (1) and a disulfide-bridged dicopper(I) complex (3) through a disulfide-bridged (mu-chloro)dicopper(I) complex (2) mediated by chloride ion has been established for the first time, providing a new redox chemistry of the transition metal-sulfur complexes. Crystal structures of 1 and 3 as well as spectroscopic features of the compounds are reported.

14.
Echocardiography ; 19(1): 15-25, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11884251

RESUMEN

OBJECTIVES: To evaluate a new indicator of left ventricular global function: Myocardial velocity gradient (MVG) M-mode Doppler tissue imaging (DTI). BACKGROUND: MVG is a new indicator of regional left ventricular function and global left ventricular diastolic function. However, it is unclear whether MVG also is an indicator of left ventricular global function in comparison with invasive indices. METHODS: We performed conventional imaging and M-mode DTI in 85 subjects and calculated MVG at the posterior wall. We obtained satisfactory images in 65 subjects, who we divided into three groups: Noninvasive study group, invasive study group, and hemodialysis group. The noninvasive study group was divided into three subgroups (a younger normal subgroup, an older normal subgroup, and a cardiomyopathy subgroup), and MVG was compared with indices of conventional imaging. In the invasive study group, we compared MVG and indices of conventional imaging with hemodynamic data (peak positive and negative dp/dt, and the time constant T) using a high fidelity micromanometer-tipped catheter. In the hemodialysis group, we compared indices before hemodialysis with those after hemodialysis. RESULTS: Peak positive MVG correlated well with peak positive dp/dt (r = 0.79), and this did not change with hemodialysis (P = 0.87). Peak negative MVG also correlated well with peak positive dp/dt and the time constant T (r = 0.88 and r = 0.80), and this did not change with hemodialysis (P = 0.97). CONCLUSIONS: Peak positive and negative MVG are sensitive and load-insensitive indicators of left ventricular function.


Asunto(s)
Cardiomiopatía Dilatada/diagnóstico por imagen , Ecocardiografía Doppler en Color/métodos , Contracción Miocárdica/fisiología , Disfunción Ventricular Izquierda/diagnóstico por imagen , Función Ventricular Izquierda/fisiología , Adulto , Anciano , Análisis de Varianza , Cardiomiopatía Dilatada/fisiopatología , Diástole/fisiología , Femenino , Humanos , Fallo Renal Crónico/terapia , Modelos Lineales , Masculino , Persona de Mediana Edad , Probabilidad , Pronóstico , Valores de Referencia , Diálisis Renal , Sensibilidad y Especificidad , Volumen Sistólico , Sístole/fisiología , Disfunción Ventricular Izquierda/fisiopatología
15.
Inorg Chem ; 43(21): 6516-8, 2004 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-15476340

RESUMEN

A novel C-S bond formation reaction took place, when a lithium phenolate derivative was treated with a disulfide-bridged dicopper(I) complex or a bis(micro-thiolato)dicopper(II) complex under very mild conditions. The reaction has been suggested to proceed via a disulfide-bridged (micro-phenoxo)dicopper(I) complex as the common reaction intermediate. Copper(II) complexes of the modified ligands containing a thioether group (products of the C-S bond formation reaction) have been isolated and structurally characterized by X-ray analysis as model compounds of the active site of galactose oxidase. Mechanism of the C-S bond formation reaction is also discussed in relation to the biosynthetic mechanism of the organic cofactor Tyr-Cys of galactose oxidase.


Asunto(s)
Hidrocarburos Aromáticos con Puentes/química , Cobre/química , Disulfuros/química , Galactosa Oxidasa/química , Modelos Moleculares , Compuestos Organometálicos/química , Sitios de Unión , Cristalografía por Rayos X , Cistina/química , Conformación Molecular , Tirosina/química
16.
Inorg Chem ; 42(24): 8087-97, 2003 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-14632530

RESUMEN

Ligand effects on the structures and redox reactivities of copper complexes have been examined using (2-pyridyl)alkylamine derivatives as the supporting ligands, where particular attention has been focused on the effects of the alkyl linker chain length connecting the tertiary amine nitrogen atom and the pyridine nucleus: N[bond]CH(2)[bond]Py (Pym) vs N[bond]CH(2)CH(2)[bond]Py (Pye). X-ray crystallographic analysis of the copper(I) complex of tridentate ligand (Phe)L(Pym2) [N,N-di(2-pyridylmethyl)-2-phenylethylamine] (complex 1) has demonstrated that it possesses a trigonal pyramidal geometry in which a d[bond]pi interaction with an eta(1)-binding mode exists between the metal ion and one of the ortho carbons of the phenyl ring of the ligand side arm (phenethyl). The result shows sharp contrast to the d[bond]pi interaction with an eta(2)-binding mode existing in the copper(I) complex of (Phe)L(Pye2) [N,N-di[2-(2-pyridyl)ethyl]-2-phenethylamine] (complex 2). Such a d-pi interaction has been shown to affect the stability of the copper(I) complex in CH(2)Cl(2). Oxygenation of copper(I) complex 1 supported by (Phe)L(Pym2) produces a bis(mu-oxo)dicopper(III) complex, also being in sharp contrast to the case of the copper(I) complex 2 with ligand (Phe)L(Pye2), which preferentially affords a (micro-eta(2):eta(2)-peroxo)dicopper(II) complex in the reaction with O(2). Such an effect of the alkyl linker chain length of the metal binding site has also been found to operate in the RSSR (disulfide)/2RS(-) (thiolate) redox system. Namely, ligand (S2,R)L(Pym1) (di[2-[(alkyl)(2-pyridinylmethyl)amino]ethyl] disulfide) with the methylene linker group (Pym) induced the reductive disulfide bond cleavage in the reaction with copper(I) ion to give a bis(micro-thiolato)dicopper(II) complex, while the ligand with the ethylene linker group (Pye), (S2,Bn)L(Pye1) (di[2-[(benzyl)(2-(2-pyridinyl)ethyl)amino]ethyl] disulfide), gave a disulfide-dicopper(I) complex. These ligand effects in the Cu(2)[bond]O(2) and Cu(2)[bond]S(2) systems have been discussed by taking into account the difference in electron-donor ability of the pyridine nucleus between the Pym and Pye ligand systems.

17.
Echocardiography ; 20(6): 495-501, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12859361

RESUMEN

BACKGROUND: Coronary flow velocity reserve (CFVR) measured by transthoracic Doppler echocardiography (TTDE) has been reported to be useful for the noninvasive assessment of coronary stenosis in the left anterior descending artery. However, the measurement of CFVR in the right coronary artery by TTDE has not yet been validated in a clinical study. OBJECTIVE: The aim of this study was to evaluate whether CFVR by TTDE can detect significant stenosis in the right coronary artery. METHODS: We studied 50 patients who underwent coronary angiography. Coronary flow velocity in the posterior descending branch of the right coronary artery (PD) was measured by TTDE both at baseline and during hyperemia induced by the intravenous infusion of adenosine triphosphate. CFVR was calculated as the hyperemia/baseline (average diastolic peak velocity). RESULTS: Adequate spectral Doppler recordings in the PD were obtained in 36 patients including 26 patients who were given an echocardiographic contrast agent to improve Doppler spectral signals. The study population was divided into 2 groups with (Group A;n = 11) and without (Group B;n = 25) significant stenosis in the right coronary artery. CFVR in Group A was significantly smaller than that in Group B (1.6+/-0.3versus2.5+/-0.4; P < 0.0001). The sensitivity of a CFVR of <2.0 for predicting the presence of significant stenosis in the right coronary artery was 91%, and the specificity was 88%. CONCLUSIONS: The measurement of CFVR in the PD by TTDE is useful for the noninvasive assessment of significant stenosis in the right coronary artery.


Asunto(s)
Circulación Coronaria , Estenosis Coronaria/diagnóstico por imagen , Ecocardiografía Doppler , Adenosina Trifosfato , Anciano , Velocidad del Flujo Sanguíneo/fisiología , Estudios de Casos y Controles , Angiografía Coronaria , Estenosis Coronaria/fisiopatología , Ecocardiografía , Femenino , Humanos , Hiperemia/inducido químicamente , Masculino , Sensibilidad y Especificidad , Función Ventricular Izquierda/fisiología
18.
Echocardiography ; 19(7 Pt 1): 555-63, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12376007

RESUMEN

Several studies have demonstrated that the ratio of peak E wave velocity/flow propagation velocity (E/FPV) using color M-mode Doppler echocardiography and the mitral E wave deceleration time make it possible to estimate left ventricular filling pressure. Recent studies have indicated that deceleration time can predict left ventricular dilation after acute myocardial infarction. The purpose of this study was to determine whether the early assessment of deceleration time and E/FPV could predict left ventricular dilation after acute myocardial infarction. We studied 55 patients with first anterior acute myocardial infarction who underwent successful coronary angioplasty by two-dimensional (2-D) Doppler echocardiography within 12 hours and at 1 and 6 months after reperfusion. Patients were divided into three groups according to deceleration time and E/FPV immediately after reperfusion: (1). restrictive filling (deceleration time < 140 msec and E/FPV > or= 2.0), (2). elevated filling pressure (deceleration time >or= 140 msec and E/FPV >or= 2.0), (3). and normal filling pressure (deceleration time >or= 140 msec and E/FPV < 2.0). The end-diastolic volume index (EDVI) was similar in the three groups immediately after reperfusion. EDVI in the groups with restrictive filling and elevated filling pressure was significantly greater than that in the group with normal filling pressure at 6 months (93 +/- 11 and 89 +/- 16 vs 59 +/- 11 ml/m(2), respectively; P < 0.0001). E/FPV shows a better correlation with the change in EDVI at 6 months than deceleration time (r = 0.77; P < 0.0001 and r = - 0.46; P < 0.001, respectively). The early measurement of E/FPV provides a simple and accurate means for predicting left ventricular dilation after acute myocardial infarction.


Asunto(s)
Dilatación Patológica/diagnóstico por imagen , Dilatación Patológica/fisiopatología , Infarto del Miocardio/diagnóstico por imagen , Infarto del Miocardio/fisiopatología , Remodelación Ventricular/fisiología , Análisis de Varianza , Velocidad del Flujo Sanguíneo , Dilatación Patológica/etiología , Ecocardiografía Doppler en Color , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/cirugía , Reperfusión Miocárdica , Valor Predictivo de las Pruebas , Función Ventricular Izquierda/fisiología
19.
Echocardiography ; 19(2): 95-102, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11926970

RESUMEN

The peak early diastolic filling velocity/flow propagation velocity (E/FPV) by color M-mode Doppler provides a better estimate of pulmonary capillary wedge pressure (PCWP) than transmitral or pulmonary venous flow. However, the value of E/FPV for the assessment of PCWP has not been evaluated in patients with acute myocardial infarction. We investigated the correlation between E/FPV and PCWP and whether PCWP can be estimated from E/FPV in patients with acute myocardial infarction. One hundred and two patients with acute myocardial infarction were divided into two groups. The first 60 patients were used to generate an equation to estimate PCWP (retrospective group). This equation was then assessed prospectively in the remaining 42 patients (prospective group). We measured the transmitral flow velocity indices and the deceleration time of diastolic pulmonary venous flow and E/FPV by Doppler echocardiography and compared these variables with PCWP measured using a pulmonary artery catheter. E/FPV was strongly correlated with PCWP (r = 0.89) in the retrospective group. The sensitivity of an E/FPV of > or = 2.0 for predicting a PCWP of > or = 18 mmHg was 95%, and the specificity was 98%. The estimated PCWP showed a strong correlation with the measured PCWP (r = 0.84, P < 0.0001) in the prospective group. The mean difference between the measured and estimated PCWP was - 0.4 +/- 3.6 mmHg. In patients with acute myocardial infarction, E/FPV by color M-mode Doppler during early left ventricular filling provides a better estimate of PCWP than transmitral or pulmonary venous flow.


Asunto(s)
Ecocardiografía Doppler en Color , Infarto del Miocardio/diagnóstico por imagen , Infarto del Miocardio/fisiopatología , Presión Esfenoidal Pulmonar/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Velocidad del Flujo Sanguíneo/fisiología , Diástole/fisiología , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Análisis Multivariante , Infarto del Miocardio/epidemiología , Variaciones Dependientes del Observador , Valor Predictivo de las Pruebas , Estudios Prospectivos , Venas Pulmonares/diagnóstico por imagen , Venas Pulmonares/fisiología , Sensibilidad y Especificidad , Estadística como Asunto , Función Ventricular Izquierda/fisiología
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