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An experimental technique to investigate fast ion confinement based on charge exchange spectroscopy of H(alpha)-light was applied to evaluate the confinement property of perpendicular fast ions in large helical device (LHD). Sensitivities of the H(alpha) spectra to the pitch angles of injected neutral beams (NBs) and these to the angle between the sight line of the measurement and NB injection path are examined. The energy dependence of the charge exchange cross section significantly affects the observed spectra since the driving NB is injected perpendicular to the magnetic field lines in the geometry of LHD. The measured spectra are compared to the spectra of GNET simulation results and the simulated spectra agreed well with the experimental measurement when we take into account the contribution of halo neutrals. Although it is difficult to obtain the fast ion distribution functions directly, this technique provides useful experimental data in benchmarking simulation codes.

A spontaneous transition phenomena between two states of a plasma with an internal transport barrier (ITB) is observed in the steady-state phase of the magnetic shear in the negative magnetic shear plasma in the JT-60U tokamak. These two ITB states are characterized by different profiles of the second radial derivative of the ion temperature inside the ITB region (one has a weak concave shape and the other has a strong convex shape) and by different degrees of sharpness of the interfaces between the L mode and the ITB region, which is determined by the turbulence penetration into the ITB region.

A new technique to measure the first and second derivatives of the ion temperature profile has been developed by using a charge exchange spectroscopy system with space modulation optics. The space observed is scanned up to +/-3 cm with a cosine wave modulation frequency up to 30 Hz by shifting the object lens in front of the optical fiber bundle by 0.5 mm with a piezoelement. The first and second derivatives of ion temperature are derived from the modulation component of the ion temperature measured by using Fourier series expansion.

Three states of a magnetic island are observed when the magnetic shear at the rational surface is modified using inductive current associated with the neutral beam current drive in the Large Helical Device. One state is the healed magnetic island with a zero island width. The second state is the saturated magnetic island with partial flattening of the T(e) profile. The third state is characterized by the global flattening of the T(e) profile in the core region. As the plasma assumes each of the three states consecutively through a bifurcation process a clear hysteresis in the relation between the size of the magnetic island and the magnetic shear is observed.

Associated with the transition from ion root to electron root, an electron internal transport barrier (ITB) appears in the large helical device, when the heating power of electron cyclotron resonance heating exceeds the threshold power. The incremental thermal diffusivity of electron heat transport chi(inc)(e) in the ITB plasma is much lower than that in the plasma with the heating power below the threshold, and the thermal diffusivity chi(e) decreases with increasing of heating power [dchi(e)/d(P/n(e))<0] in helical ITB plasmas.

In preheparin serum, there exists lipoprotein lipase (LPL) mass with little activity. The clinical significance of this preheparin serum LPL mass (preheparin LPL mass) is unclear. We studied the levels of preheparin LPL mass in patients with coronary atherosclerosis, comparing the results with those in healthy men. We also evaluated the correlation between preheparin LPL mass and the severity of coronary atherosclerosis by comparing with other risk factors such as age, smoking, family history, hypertension, hyperuricemia, diabetes mellitus, total cholesterol, triglyceride, high density lipoprotein-cholesterol and body mass index. The subjects, 70 men presenting with symptoms of coronary artery disease, underwent coronary angiographic examination. Significant narrowness was defined as > or = 75%. Control group comprised 77 men who had annual health checks and showed no abnormal findings. Preheparin LPL mass in the stenosis group was lower than normal coronary group and also than the control group. Multivariate analysis showed that preheparin LPL mass had the highest t-value (-2.53) for the number of lesions among the risk factors listed above. These results suggest that low preheparin LPL mass may be deeply involved in the progression of coronary atherosclerosis.

Background Since long-term administrations of anti-hyperlipidemic agents result in reduction in % stenosis or increase in minimum lumen diameter (MLD) of stenotic coronary segments, it is generally believed that anti-hyperlipidemic agents stabilize vulnerable coronary plaques. However, recent pathologic and angioscopic studies revealed that vulnerability of coronary plaques is not related to severity of stenosis and the rims rather than top of the plaques disrupt, and therefore, angiography is not adequate for evaluation of vulnerability.Angioscopy enables macroscopic pathological evaluation of the coronary plaques. Therefore, we carried out a prospective angioscopic open trial for evaluation of the stabilizing effects of bezafibrate on coronary plaques.Methods From April, 1997 to December, 1998, 24 patients underwent coronary angioscopy of the plaques in the non-targeted vessels during coronary interventions and 6 months later. The patients were divided into control (10 patients, 14 plaques) and bezafibrat (14 patients, 21 plaques) groups. Oral administration of bezafibrate (Bezatol SR, 400mg/day) was started immediately after the interventions and was continued for 6 months. The vulnerability score was determined based on angioscopic characteristics of plaques and it was compared before and 6 months later.Results Six months later, vulnerability score was reduced (from 1.6 to 0.8;p < 0.05) in bezafibrate group and unchanged (from 1.4 to 1.3; NS) in control group. In bezafibrate group, the changes in vulnerability score was not correlated with those in % stenosis or MLD. Conclusion The results indicate that bezafibrate can stabilize coronary plaques.

Endocardial lesions are caused not only by inflammatory processes but also by myocardial ischemia, resulting in endocardial thrombosis and cerebral embolism. We deviced a method for direct visualization of endocardial damages by a novel dye image cardioscopy with Evans blue and examined its feasibility in patients with heart disease. The dye was injected into the left ventricle before and after endomyocardial biopsy. Endocardial surface was stained in dark blue in 63% of patients with angina pectoris before biopsy. After biopsy, the biopsied portions were stained in blue in all. The results indicate that endocardium is damaged even in apparently intact LV in patients with ischemic heart disease and that endomyocardial biopsy causes severe endocardial damages.

Pemirolast potassium, an antiallergic agent, has preventive effects against restenosis after percutaneous transluminal coronary angioplasty (PTCA). This study investigated the mechanism of the preventive effects of pemirolast on restenosis using serial intravascular ultrasound (IVUS). Initial elective PTCA was performed in consecutive 106 patients from March 1996 through August 1997. Patients with type C lesions or graft stenosis were excluded from the study. A total of 97 patients with 110 lesions, 48 patients (56 lesions) in the pemirolast treated group and 49 patients (54 lesions) in the control group were analyzed. Restenosis was defined as a diameter stenosis of > or = 50% at follow-up study. Patients in the pemirolast group received 20 mg/day from the morning after angioplasty until the time of follow-up (mean 6 months). The lumen cross-sectional area, vessel area, plaque area, and % plaque area were measured by quantitative coronary ultrasound and compared after PTCA and at follow-up between the patients without restenosis in the pemirolast (28 lesions) and control (27 lesions) groups. There was no significant change in baseline characteristics between the 2 groups. Restenosis rate per lesion was significantly lower in the pemirolast group than in the control group (23.2% vs 44.4%, p < 0.05, respectively). After angioplasty and at follow-up study, there was no difference in lumen and vessel cross-sectional areas between the 2 groups. However, plaque and % plaque area in the pemirolast group were smaller than in the control group at follow-up study (8.9 +/- 2.3 vs 11.8 +/- 3.5 mm2, p < 0.005, 56.0 +/- 9.0% vs 64.0 +/- 10.4%, p < 0.005, respectively). These results suggest that suppression of neointimal hyperplasia is the preventive mechanism of pemirolast against restenosis after angioplasty. Pemirolast may be more effective against restenosis after coronary stenting.

Background: We recently confirmed that pemirolast potassium, an antiallergic agent, markedly inhibits migration and proliferation of vascular smooth muscle cells. It has also been reported that pemirolast inhibits intimal hyperplasia in animal experiments., Methods and Results: To elucidate the preventive effects of pemirolast on restenosis after percutaneous transluminal coronary angioplasty (PTCA), 227 patients were enrolled in this prospective, randomized trial. A total of 205 patients who were compatible with the protocol were analyzed (pemirolast group, 104 patients with 140 lesions; control group, 101 patients with 133 lesions). Patients in the pemirolast group received 20 mg/d of pemirolast from 1 week before PTCA until the time of follow-up angiography (4 months after PTCA). Angiographic restenosis was defined as diameter stenosis >/=50% at follow-up. Restenosis rates were significantly lower in the pemirolast group than in the control group (24.0% vs 46.5% of patients, 18.6% vs 35.3% of lesions, P <.01, respectively). During 8 months of follow-up, there were no coronary events (death, myocardial infarction, coronary artery bypass surgery, or repeated PTCA) in 81.7% of the pemirolast group and in 63.4% of the control group (P =.013)., Conclusions: This study suggested that pemirolast would be useful in the clinical setting to prevent restenosis after PTCA.

The effects of repetitive myocardial ischemia on collateral circulation, ST deviation and epicardial wall motion were examined in 12 patients undergoing percutaneous transluminal coronary angioplasty (PTCA) for single left anterior descending artery disease. Rentrop collateral filling grade was assessed using contrast injection to the contralateral artery during the first and final episodes of coronary occlusion. ST deviation was measured by intracoronary electrocardiography. Epicardial wall motion (%pre PTCA) was measured by guide wire motion analysis according to the centerline method. Collateral filling grade was assessed 30 sec after balloon inflation. The ST segment and the epicardial wall motion were measured 60 sec after balloon inflation and deflation, respectively. There was no change in the collateral filling grade between the first and final episode of coronary occlusion. Patients with collateral filling grade I (R-I group, n = 4), II (R-II group, n = 3) and III (R-III group, n = 5) during coronary occlusion showed mean ST segment shifts of 13.2, 9.4, and 0.9 mm, respectively, and mean epicardial wall motion of 41.4%, 67.2%, and 78.5%, respectively. The collateral filling grade correlated with ST deviation and epicardial wall motion, and there was a significant correlation between epicardial wall motion and ST deviation (r = -0.67). Comparison of the R-I group or severe ischemia (n = 4) and the R-III group or slight ischemia (n = 4) during coronary occlusion for the fourth time showed the effect of preconditioning was obtained in R-I group. More R-III group patients than R-I group had hyperkinetic epicardial wall motion during coronary reperfusion. Stunned myocardium was demonstrated in both R-I group and R-III group patients. Epicardial wall motion was poorer in the R-I group than R-III group. We concluded the following: There is no change in the grade of collaterals during repetitive coronary occlusion, and there is a relationship between the grade of collateral and degree of myocardial protection; there is good correlation between ST segment and epicardial wall motion; ischemic preconditioning is obtained during repetitive severe myocardial ischemia; recovery from brief episodes of slight myocardial ischemia is associated with hyperkinesia of epicardial wall motion; the reduction of stunned myocardium is related to the degree of premyocardial ischemia; preconditioning is sufficient to cause myocardial stunning, but myocardial stunning is insufficient to cause preconditioning.

Left ventricular systolic function in patients with acute myocardial infarction was assessed by Doppler echocardiographic measurement of left ventricular ejection flow velocity and maximum acceleration in 20 patients with initial acute anteroseptal myocardial infarction (group A) and 15 age-matched normal subjects. All patients underwent emergency reperfusion therapy by direct percutaneous transluminal coronary angioplasty (direct PTCA). Pulsed Doppler echocardiograms were obtained from sample volume immediately below the aortic valve in the apical long-axis view. Three parameters, peak velocity, ratio of acceleration time to ejection time (AT/ET) and maximum acceleration, were measured by the Doppler analysis program. Changes in the 3 parameters from the day of admission to the 3rd post-admission day were also observed in 15 patients. Although no significant difference was observed in AT/ET in the 2 groups, peak velocity and maximum acceleration in the patient group were significantly lower than those in the normal group (peak velocity: 90.8 +/- 13.1 vs 99.4 +/- 9.7 cm/sec, p < 0.05, maximum acceleration: 2,692.4 +/- 604.5 vs 3,410.2 +/- 712.5 cm/sec2, p < 0.01, respectively). Between the admission and 3rd day, peak velocity and AT/ET did not change significantly, but maximum acceleration increased significantly (2,720.5 +/- 676.7, 1st day vs 3,313.9 +/- 947.5 cm/sec2, 3rd day, p < 0.05). These results indicate that the maximum acceleration measured by pulsed Doppler echocardiography is useful for assessing global left ventricular systolic function in acute myocardial infarction. Direct PTCA results in improved ventricular systolic function on the 3rd post-operative day.

A mass-fusion splicer for single-mode four-fiber ribbon has been developed with an accurate splice loss estimation function capability. Measurements in two orthogonal directions are used to obtain a high axis offset resolution of 0.3 microm. An average splice loss of 0.05 dB and an average splice loss estimation error of -0.002 dB are achieved.