Search PubMed⌕ Search

Biomedical subjects

Kazuyuki Ozaki

Publications and source records attributed to Kazuyuki Ozaki.

13 recordsLinked to original sources

The anti-atherosclerotic effects of lipid lowering with atorvastatin in patients with hypercholesterolemia.

We investigated the lipid lowering and anti-atherosclerotic effects of atorvastatin in patients with hypercholesterolemia. Thirty patients were given atorvastatin 10 mg daily, and assessed for serum lipids, intima-media thickness (IMT), and brachial-ankle pulse wave velocity (ba-PWV) at the baseline, 6 months, and 12 months. Remnant-like particle-cholesterol (RLP-C), lipoprotein (a)(Lp(a)), and high-sensitivity C-reactive protein (hs-CRP) were measured in some patients at the baseline and at 6 months. Total cholesterol, triglyceride and low-density lipoprotein cholesterol were significantly decreased by 32%, 23% and 44% at 6 months, respectively, and these effects were sustained at 12 months. There was no change in high-density lipoprotein cholesterol. IMT at the baseline was 0.88 +/- 0.16 mm and decreased to 0.76 +/- 0.13 mm at 6 months, remaining at 0.75 +/- 0.12 mm at 12 months. We did not observe any significant changes in ba-PWV. RLP-C and hs-CRP were significantly reduced from 7.3 +/- 10.8 mg/dL to 4.3 +/- 5.3 mg/dL and 0.075 +/- 0.065 mg/dL to 0.039 +/- 0.043 mg/dL at 6 months, respectively. There was no change in Lp(a). The observed decrease in IMT suggests that atorvastatin possibly improves atherosclerosis, in addition to the significant reduction of serum lipids.

Aged↗

Aortocoronary dissection complicated with percutaneous coronary intervention: a case report.

A 74-year-old female developed aortocoronary dissection during percutaneous coronary intervention. The forceful manipulation of the guide catheter and contrast medium injection seemed to be the cause of the aortocoronary dissection involving the coronary sinus of Valsalva. The entry of the dissection was closed with subsequent obliteration of the false lumen by coronary stenting under the guidance of intracoronary ultrasonography and angiography.

Aged↗

Estimating the fasting triglyceride concentration from the postprandial HDL-cholesterol and apolipoprotein CIII concentrations.

Hypertriglyceridemia is an important risk factor for atherosclerosis. In the fasting state, the triglyceride (TG) concentration is correlated significantly with the high-density lipoprotein-cholesterol (HDL-C) and apolipoprotein CIII (apoCIII) concentrations. A postprandial change is evident in TG, but negligible in HDL-C and apoCIII. We investigated whether the fasting TG concentration could be estimated from the postprandial HDL-C and apoCIII concentrations. We measured the TG, HDL-C, and apoCIII concentrations at seven points a day in 58 inpatients. Multiple regression analysis showed that the actual fasting TG concentration was strongly correlated with the TG concentration estimated from the fasting HDL-C and apoCIII concentrations (ln[TG](fasting)=0.0140[apoCIII](fasting)-0.724[HDL-C](fasting)-0.142, r=0.852, p<0.001). This equation was also fit to the fasting data from 163 outpatients (r=0.883, p<0.001). Although the TG concentration increased by up to 28.2%, the HDL-C and apoCIII concentrations changed little during the day. When we substituted the postprandial HDL-C and apoCIII concentrations for the respective fasting values in this equation, there were still strong positive correlations (r=0.794-0.840) between the actual and estimated fasting TG concentrations throughout the day. In conclusion, the fasting TG concentration can be estimated from the postprandial HDL-C and apoCIII concentrations.

Aged↗

High-output heart failure caused by arteriovenous fistula long after nephrectomy.

A 70-year-old Japanese woman was admitted to our hospital because of anasarca. At 32 years of age, she had undergone nephrectomy for renal tuberculosis. A continuous abdominal bruit was heard. The chest X-ray showed cardiomegaly and dilatation of the pulmonary artery. Abdominal three-dimensional computed tomography scanning clearly revealed an arteriovenous fistula. Cardiac catheterization disclosed cardiac output of 9.2 l/min and a step-up of oxygen saturation at the renal vein level of the inferior vena cava. Surgical closure of the fistula promptly decreased her cardiac output and improved the heart failure. This is a rare case of an arteriovenous fistula developing long after nephrectomy and causing high-output heart failure.

Aged↗

Esophageal varices without portosystemic venous pressure gradient in a patient with post-pericardiotomy constrictive pericarditis: a case report.

A 51-year-old woman was admitted with intractable congestive heart failure and progressive anemia. She had undergone mitral valve replacement for mitral regurgitation at age 23 years. Subsequently, her mitral prosthesis was replaced twice due to thrombotic stack and valve insufficiency. Signs of congestive heart failure became evident at age 46 years. Gastrointestinal endoscopy revealed esophageal varices, which were treated by endoscopic variceal ligation. Cardiac catheterization disclosed elevated pulmonary capillary wedge pressure (mean 16 mmHg), right atrial pressure (mean 15 mmHg), and hepatic vein wedge pressure (mean 15 mmHg). She died at age 53 years. Autopsy showed severe congestive liver but not liver cirrhosis. Esophageal varices may progress in spite of the absence of porto-systemic pressure gradient in patients with severely high venous pressure.

Central Venous Pressure↗

Plasma concentrations of monocyte chemoattractant protein 1 (MCP-1) and neopterin in the coronary circulation of patients with coronary artery disease.

BACKGROUND: The dynamics of MCP-1 and neopterin and the relation between their concentrations in coronary circulation and the severity of coronary atherosclerosis were evaluated in patients with stable coronary artery disease (CAD). METHODS AND RESULTS: Blood samples were obtained from the aortic root (Ao) and coronary sinus (CS) of 78 patients who underwent coronary angiography. Plasma MCP-1 and neopterin concentrations were measured using an enzyme-linked immunosorbent assay method and the CS-Ao differences were calculated. The severity of coronary heart disease (CHD) was evaluated in 52 patients who had no history of coronary angioplasty, using 3 coronary scoring systems: the clinical 1- to 3-vessel disease score, the American Heart Association extension score (1-15 segments), and the Gensini score. The plasma MCP-1 and neopterin concentrations increased significantly with age. The CS-Ao differences for neopterin showed weak, but significant, positive correlation with the Gensini score (r=0.347, p=0.013). There were no correlations among the MCP-1 concentrations in the Ao or CS, or in the CS-Ao difference, with the severity of CHD. CONCLUSIONS: The results indicate that neopterin is a useful marker of the severity of coronary atherosclerosis in patients with stable CAD, acting as an index of the activity of monocytes/macrophages.

Adult↗

Decrease in plasma NOx concentration by isosorbide dinitrate, an organic nitrate ester.

It has been suggested that isosorbide dinitrate (ISDN)-induced venodilation could be ascribed to preferential accumulation of the agent in venous tissues, resulting in higher concentrations of nitric oxide (NO). Here, the authors investigated whether the venodilating effect of ISDN is associated with a preferential increase in plasma concentrations of NOx (NO2- and NO3-, stable end-products of NO) in venous blood than arterial blood. Plasma NOx was measured by high-performance liquid chromatography-Griess system with a sensitivity of 0.01 microM for NO2- and 0.1 microM for NO3-. Arterial and venous blood samples were obtained after coronary angiography from the aorta and right atrium of patients with or without ischemic heart disease. Nicardipine, a calcium channel blocker, was used as a non-NO-related arteriovasodilator. At 1 mg i.v., it did not cause any changes in NOx concentration in arterial and venous blood irrespective of hemodynamic changes. However, ISDN (3 mg i.v.) increased NO2- and decreased NO3- in both arterial and venous blood, with concomitant venodilation. Further analysis revealed that plasma NO increased in the pulmonary circulation and this increase was preserved after nicardipine and ISDN, and that ISDN, but not nicardipine, increased plasma NO3- in the pulmonary circulation. The authors did not detect higher concentrations of NOx in venous blood relative to their level in arterial blood. Further studies are necessary to clarify the kinetics of NO and NO-related compounds in the whole body.

Aged↗

Significance of asymmetric dimethylarginine (ADMA) concentrations during coronary circulation in patients with vasospastic angina.

The basal activity of nitric oxide (NO) is reduced in spastic arteries of patients with vasospastic angina (VSA). Elevated concentrations of ADMA are associated with reduced NO production and impaired endothelium-dependent vasodilatation. The aim of this study was to elucidate the role of ADMA and its relationship to NO end-products (NOx; nitrate + nitrite) during coronary circulation in patients with VSA. The plasma ADMA and NOx concentrations during coronary circulation were evaluated in 16 VSA and 16 control patients. Blood samples were obtained from the coronary sinus (V) and the ostium of the left coronary artery (A), and the (V-A) differences of ADMA and NOx were determined. The coronary sinus plasma ADMA concentration in patients with VSA was higher than that in the control. The coronary sinus - arterial (V-A) difference of NOx was negative in the VSA group and approximately zero in the control group (VSA group =-1.4 micromol/L, control group =-0.1 micromol/L, p=0.0005). Furthermore, in the VSA patients, there was a negative correlation between the (V-A) difference of NOx and the basal coronary artery tone at the site of spasm (r=-0.60, p=0.015). A significant negative correlation between the (V-A) differences of NOx and ADMA was observed in patients with VSA (r=-0.52, p<0.05), but not in those of the control. Higher ADMA concentrations might cause the reduced formation of NO that underlies the pathophysiology of coronary vasospasm.

Aged↗

Highly vascular pelvic tumor causing high-output heart failure because of massive arteriovenous shunting: a case report.

A 53-year-old Japanese woman underwent investigation of her heart murmur. A continuous abdominal bruit was heard. Blood gas analysis and chest X-ray showed congestive heart failure. Enhanced computed tomography of the pelvis showed a 10 x 4 cm hypervascular tumor in the retroperitoneal space. Cardiac catheterization disclosed a cardiac output of 13.2 L/min and a step-up of oxygen at the right common iliac vein. Abdominal aortic angiography showed an extremely vascular pelvic tumor and rapid filling of the inferior vena cava. This is a rare case of a highly vascular pelvic tumor causing high-output heart failure because of th massive arteriovenous shunting.

Arteriovenous Fistula↗

Effects of 4,4'-diisothiocyanato-stilbene-2,2'-disulfonic acid (DIDS) and chlorpromazine on NO3- transport via anion exchanger in erythrocytes: inertness of DIDS in whole blood.

We examined the effects of chlorpromazine on NO(3)(-) transport between erythrocytes (RBCs) and extracellular fluid. Chlorpromazine (10 microg/ml) did not influence NO(3)(-) movement in both whole blood and RBC suspension. Though an anion exchanger (AE1) inhibitor DIDS (4,4'-diisothiocyanato-stilbene-2,2'-disulfonic acid, 100 microM) did not alter NO(3)(-) movement in whole blood, it inhibited the movement in a concentration-dependent manner in the RBC suspension. The inhibition was abrogated by plasma and albumin concentration-dependently. Our results indicated that chlorpromazine had no effect on NO(3)(-) transport through AE1 and that the inertness of DIDS on AE1 in whole blood is due to interference by albumin in plasma.

4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid↗

Plasma levels of soluble thrombomodulin, C-reactive protein, and serum amyloid A protein in the atherosclerotic coronary circulation.

Plasma levels of C-reactive protein (CRP) and serum amyloid A protein (SAA), inflammatory markers, and soluble thrombomodulin (s-TM), a marker of endothelial damage. are thought to be related to coronary artery disease. However, the relationship between these inflammatory markers and endothelial injury in atherosclerotic coronary arteries is still unclear. Fifty-five patients who underwent coronary angiography were classified into 3 groups according to the severity of left coronary arterial atherosclerosis evaluated by the Gensini score (GS; normal: score = 0, n = 15; mild: 0 < score < 15, n = 29; severe: score > or = 15, n = 11). Blood samples were obtained from the aortic root (Ao) and coronary sinus (CS) and plasma CRP and SAA levels were measured by latex turbidimetric immunoassays, and s-TM levels were determined by an enzyme-linked immunosorbent assay. The difference between marker concentrations in the Ao and CS of the coronary circulation was expressed as the coronary sino-arterial (CS-Ao) difference. The CS-Ao differences of s-TM and SAA were significantly higher in patients with severe atherosclerosis than in normal patients (P < 0.01), and showed weak but significant positive correlations with the GS (r = 0.34, P < 0.01 and r = 0.33, P < 0.05, respectively). The CS-Ao differences in CRP did not differ among the three groups, and did not correlate with the GS. The results of our study reveal a possible relationship between endothelial cell injury and inflammation in atherosclerotic coronary arteries.

Aged↗

Association between coronary endothelial dysfunction and local inflammation of atherosclerotic coronary arteries.

We have examined a possibility whether or not severity and extent of coronary atherosclerosis may associate with degree of local inflammation in relation to endothelial dysfunction as is indicated by reduced NO formation. Blood samples were obtained from aortic root (Ao) and coronary sinus (CS) of 39 patients who underwent coronary angiography. Plasma NOx levels (nitrite + nitrate, stable NO end-products) were evaluated by HPLC-Griess system, and markers of inflammation, C-reactive protein (CRP) and serum amyloid A protein (SAA), were measured by Latex Turbidimetric Immunoassay. To evaluate the changes of these substances through coronary circulation, the percentage changes of respective markers [(CS - Ao) x 100/Ao] were calculated. The extent and severity of atherosclerosis of left coronary arteries were evaluated with Gensini Score (GS). The GS correlated with the percentage changes of NOx (r = -0.35, p < 0.05) and that of SAA (r = 0.43, p < 0.05) across coronary circulation, but not with changes in CRP. Moreover, the percentage changes of NOx correlated with that of SAA (r = -0.36, p < 0.05). These results indicated that severity and extent of coronary atherosclerosis related to degree of local inflammation which has a possible association with coronary endothelial dysfunction.

Biomarkers↗

Levels of soluble E-selectin and ICAM-1 in the coronary circulation of patients with stable coronary artery disease: association with the severity of coronary atherosclerosis.

The recruitment of circulating leukocytes to atherosclerotic sites is mediated by a family of adhesion molecules. The objective of the present study was to evaluate the relationship between circulating adhesion molecule levels in the coronary circulation and the severity of coronary atherosclerosis in patients with stable coronary artery disease. The subjects were 79 patients undergoing coronary angiography. According to the severity of coronary atherosclerosis as assessed by the Gensini Score (GS) of the left coronary artery, they were classified into three groups: group C (no organic stenosis, score 0, n = 14), group M (mild organic stenosis, score 1-13, n = 39) and group S (severe organic stenosis, score > or = 14, n = 26). Blood samples were taken from the aorta (Ao) and coronary sinus (CS), and plasma levels of soluble E-selectin (sE-selectin) and soluble intercellular adhesion molecule-1 (sICAM-1) were measured by enzyme-linked immunosorbent assay. These levels were then compared between groups. There were no significant differences in plasma sICAM-1 levels in the Ao or CS between the three groups. The difference in sICAM-1 levels between the CS and Ao (CS-Ao) also showed no significant difference. Plasma sE-selectin levels in both the Ao and CS were significantly higher in group S than in groups C and M (p < 0.05), but there were no significant differences in CS-Ao. There was a weak but significant correlation between the plasma levels of these adhesion molecules and the number of coronary risk factors present. Multivariate analysis showed that the number of coronary risk factors was the only positive predictor (p = 0.0048) of the GS; there was no association between the plasma level of either adhesion molecule and the GS. In patients with stable coronary artery disease, sICAM-1 plasma levels do not indicate the severity of coronary atherosclerosis, while sE-selectin plasma levels appear to reflect the severity of systemic rather than coronary atherosclerosis.

Adult↗