An autoradiographic study using 55Fe was performed to investigate the distribution of iron in the ameloblasts and enamel of rat incisors. The study of methodological problem s of 55Fe autoradiography revealed that in the undecalcified sections, the radiation by 55Fe within the ameloblasts and pigmented enamel produced grain scattering over the facing enamel surface and ameloblasts, respectively. The findings indicate that the autoradiographic observation of the enamel surface should be made using the incisors freed from the enamel organ and that the observation of the ameloblasts should be done in the region other than the zone of enamel pigmentation. After the55Fe injection 55Fe incorporation into the ameloblasts was observed in the maturation stage, reaching the maximum at 24 hours. The peak of 55Fe distribution in the ameloblasts moved from the early stage to the later stage of maturation between 24 hours and 7 days after the injection. At 3 and 7 days after the 55Fe injection, 55Fe was deposited markedly on the enamel surface at the end of maturation where the enamel pigmentation occurs. The present study established the utility of 55Fe autoradiography when applied on the undecalcified section of rat incisors and it was demonstrated that iron is incorporated into the maturation ameloblasts and secreted onto the enamel surface at the end of maturation.
The pathogenetic roles of platelets were studied in unilateral progressive Masugi nephritis in the rabbit. On fourteenth day after the injection of anti-kidney serum, peripheral platelet counts, platelet aggregation and platelet aggregation rate were not changed statistically compared with those before the initial injection. The presence of platelet antigen within the glomeruli of the unclamped nephritic kidney suggests the participation in the pathogenesis of glomerular lesion. No significant difference was observed in the intrarenal uptake of 111Indium-labeled platelets between clamped and unclamped kidneys. This is probably due to the possibility of the participation of the very small amount of platelets or the possible decreased renal blood flow in the nephritic side in this model, or the active uptake of platelet not being found in this progressed stage of this model.
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.
To determine the predictive risk factors of the severity of the coronary artery disease, the serum levels of lipoprotein cholesterol and apolipoprotein were measured in 103 patients undergoing coronary angiography examination for suspected myocardial ischemia. The extent and severity of the coronary artery disease (CAD) were assessed by assigning scores to each lesion. Twenty-six female patients (59±8 yrs.) showed a stronger relationship of apo B and apo A-1/B to the coronary scores than the 77 male patients (57±8 yrs.). The male patients were divided into four groups based on the coronary scroes: H-CAD (range: over 11points), M-CAD (5-10 points), L-CAD (1-4 points) and N-CAD (0 point). The atherogenic risk factors other than the abnormalities in lipid metabolism (obesity index, fasting plasma glucose, smoking and blood pressure) were well matched in the four groups. T.C., LDL-C., HDL-C., HDL2-C., apo B, apo A-1/B ratio and apo A-II/B ratio significantly differed in the H-CAD and N-CAD groups. These results indicate that T.C., LDL C., HDL-C., HDL2 C., apo B, apo A-1/B ratio and apo A-Il/B ratio are predictive risk factors of the coronary heart disease. Furthermore, apo B and apo A l/B ratio significantly differed in the H-CAD and L-CAD groups. These results suggest that apo B and apo A-1/B ratio may be good discriminators of the severity of the coronary heart disease.