Combined system of synchrotron radiation and laser for solid-state research.

Two combined systems of synchrotron radiation and laser have been constructed for solid-state research. One is a laser-induced fluorescence system to observe synchrotron radiation-induced desorption of alkali atoms from ionic crystals, which consists of a laser diode with a high repetition rate and synchrotron radiation under a single-bunch operation. The other is a system of two-photon spectroscopy, which is based on the combination of synchrotron radiation pulses with a low intensity and high repetition rate and Nd:YAG laser pulses with a high intensity and low repetition rate. The experimental systems and the preliminary results are presented in this report.

Hemodynamic effects and pharmacokinetics of long-term therapy with ibopamine in patients with chronic heart failure.

To evaluate the attenuation of the effectiveness of long-term ibopamine therapy, ibopamine was administered in single doses of 100 and 200 mg to 10 patients with chronic heart disease. The hemodynamic studies using Swan-Ganz catheter and pharmacokinetic studies were carried out. Ibopamine was found to increase cardiac output and stroke index and to decrease systemic vascular resistance in this acute study. Six patients underwent long-term therapy with the drug and were evaluated for the development of tolerance. Three out of 5 patients experienced an improvement in NYHA functional class after 12-23 weeks of treatment. There was no attenuation in the effects of ibopamine on hemodynamics, pharmacokinetic parameters remained almost unchanged, and tolerance was not observed. These results suggest that ibopamine is useful as an orally administered anti-heart failure drug.

[The prevalence and clinical features of pathologically abnormal mitral valve leaflets (myxomatous mitral valve) in the mitral valve prolapse syndrome: an echocardiographic and pathological comparative study].

We studied the prevalence and clinical features of pathologically abnormal mitral valve leaflets (myxomatous mitral valve: MMV) in consecutive 142 patients with the mitral valve prolapse syndrome (MVP). Our echocardiographic criteria for MMV were 1) thick leaflets 3 mm or greater, 2) redundant leaflet-motion, and 3) echo-density lower than that of the aortic walls. The echocardiographic measurements of left ventricular diastolic dimensions (LVDd), percent fractional shortening (%FS), mitral annular diameter (MAD), and LV mass were compared between MMV and non-MMV groups. Twelve patients (8%) were referred for surgery because of congestive heart failure, and two patients died during the observation periods. Gross morphology of the MMV was characterized by increased surface area, dome formation of the leaflet-body, and non-uniform leaflets in thickness, and histologic findings of the MMV were the infiltration of spongiosa layer into the fibrosa layer. The diagnostic accuracy of echocardiography for the MMV was examined in 14 patients underwent either surgery or autopsy, and it was high (78% in sensitivity and 80% in specificity). The progression of mitral regurgitation (MR) from mild to moderate grade or mild to severe grade was found in five of 26 patients during follow-up studies over 12 months (mean = 36 months). All of the five patients were aged 50 years and older. While, MR completely disappeared in a 17-year-old boy with marked physical development within three years of the observation period. Mitral annular diameter significantly increased in MMV with MR when compared to non-MMV with MR (4.1 +/- 0.7 vs 3.5 +/- 0.4). But no significant changes were noted in LVDd and LV mass between non-MMV with MR and MMV with MR. Of the 142 patients with MVP, 96 patients were non-MMV and 46 patients were MMV. Ruptured chordae tendineae were associated in 5/96 patients (5%) with non-MMV and 22/46 patients (48%) with MMV. Intracardiac vegetations were seen in four of the 96 patients (4%) with non-MMV. The prevalence of MMV in MVP was greater in older patients, and it reached nearly as high as 50% of MVP patients aged 60 years and older. In conclusion, the echocardiographic diagnostic criteria for MMV are reliable with high sensitivity and specificity, and are useful to predict the high risk patients in the MVP syndrome. MMV may be a potential etiology causing aggravation of mitral regurgitation and/or ruptured chordae tendineae.

Hemodynamic comparison of combined therapy by nitroglycerin tape and ibopamine with combination of nitroglycerin tape and nifedipine.

Fifteen congestive heart failure patients (NYHA: class III or IV) were enrolled in the study and were classified into two groups. Six patients (group I) received combined therapy by nitroglycerin tape (5 mg) and ibopamine (100 mg), while the remaining 9 patients (group II) were given nitroglycerin tape (5 mg) and nifedipine (10 mg). The effects of the combined treatments on hemodynamics were compared between the two groups using Swan-Ganz catheter method. No significant differences were noted in the hemodynamic baseline values of the two groups before treatment. In group I mean pulmonary arterial pressure (mPA) and systemic vascular resistance (SVR) decreased and the cardiac index (CI) increased, while the heart rate (HR) and mean blood pressure (mBP) remained unchanged. In group II mBP, mPA and SVR were lowered, whereas CI and HR were augmented. There were no significant differences between the two groups with respect to mPA and CI. However, mBP decreased in group II, while it remained unchanged in group I, with significant difference between the two groups (p less than 0.01). Preload and afterload, on the base of mPA and SVR, respectively, decreased in both groups, while cardiac output increased, suggesting that both treatments were useful for the improvement of cardiac output. Mean BP decreased in group II, although it remained unchanged in group I. These results suggest that the combination of nitroglycerin and ibopamine may be more useful in hypotensive patients with heart failure.

Hemodynamic effects of molsidomine on weight sustaining isometric exercise in patients with ischemic heart disease.

Hemodynamic effects of 2 mg of sublingual molsidomine were evaluated in 11 patients with ischemic heart disease using a weight-sustaining isometric exercise (WSIE) that we developed. Left ventricular end diastolic pressure (LVEDP), mean pulmonary pressure, mean systemic arterial pressure (mAP), cardiac index and stroke work index increased significantly during WSIE before and after molsidomine. Although WSIE resulted in a similar rise of mAP before and after molsidomine, the increment value of LVEDP during WSIE was significantly lower after molsidomine. The recovery time to the resting state of all parameters was shorter and the left ventricular function curves showed a leftward deviation with molsidomine. In conclusion, the results suggest that molsidomine will produce a preload reduction and improve the left ventricular function during WSIE in patients with ischemic heart disease.