Aging and scar tissue in human heart muscle

Histometrical estimation of scar tissue was made on 30 human hearts obtained at autopsy in order to know possible correlations between aging and scar tissue in the heart muscle. Estimation was made on histological specimens of the anterior wall of the left ventricle and the posteromedial papillary muscle, according to Chalkley's point counting method, and the amount of scar tissue was expressed in percentage. The mean percentages were 3.11, 5.26 and 9.24 in the epicardial, endocardial parts of the left ventricle and the papillary muscle, respectively. There were very significant differences between these 3 mean percentages. There were very significant correlations between the percentages of scar tissue in these 3 parts and ages. From these results, it is concluded that the scar formation increases in the heart muscle with aging.

Determination of hydroxyproline content in human heart muscle

Hydroxyproline content was chemically determined on 45 human hearts obtained at autopsy in order to study whether hydroxyproline contents vary in proportion to heart weight or not. There were no significant differences in the mean hydroxyproline content between the epicardium and the endocardium, between the left ventricle and the right ventricle, or among cardiovascular and renal disease group, malignant disease group and miscellaneous disease group. Total hydroxyproline content per mg dry weight of the left ventricle increased proportionally with heart weight. Hydroxyproline content in neutral salt soluble fraction increased more proportionally than that in acid soluble fraction. This tendency was more evident in the endocardium than in the epicardium of the left ventricle. These results seem to be well consistent with those of histometrical estimation of scar tissue in human heart muscle. Hydroxyproline content in acid soluble fraction of the right ventricle was increased proportionally with heart weight.

Purification of bisphosphoglyceromutase, 2,3-bisphosphoglycerate phosphatase and phosphoglyceromutase from human erthrocytes. Three enzyme activities in one protein

Bisphosphoglyceromutase, 2,3-bisphosphoglycerate phosphatase and phosphoglyceromutase have been purified from human red cells. Three enzymes were co-purified throughout all purification steps. Three fractions (peaks I, II and III) which were chromatographically separable and had three activities in different ratios were obtained. Peak III which contained the main bisphosphoglyceromutase and 2,3-bisphosphoglycerate phosphatase activities was purified to homogeneity by electrophoretic and ultracentrifugal analyses. The homogeneous preparation had the phosphoglyceromutase activity. The three activities were lost at the same rate during thermal inactivation. Thus, bisphosphoglyceromutase and 2,3-bisphosphoglycerate phosphatase activities, which are responsible for 2,3-bisphosphoglycerate metabolism in red cells, are displayed by the same enzyme protein which has phosphoglyceromutase activity. Peaks I and II were rich in the phosphoglyceromutase activity. Both peaks showed bisphosphoglyceromutase and 2,3-bisphosphoglycerate phosphatase activities, although these two activities were much smaller than those of peak III. Some of the enzymic properties of peak III are described. Comparative studies on three peaks showed that the phosphoglyceromutase of peak III differed from that of peaks I and II in the kinetic property and thermostability.

Histometrical estimation of scar tissue in hypertrophied human heart muscle

Histometrical estimation of scar tissue was made on 28 hypertrophied human hearts obtained at autopsy in order to know the significance of scar tissue in the process of cardiac hypertrophy and in the development of cardiac failure. Estimation was made on histological specimens of the anterior wall of the left ventricle and the posteromedial papillary muscle, according to Chalkley's point counting method, and the amount of scar tissue was expressed by percentages. The mean percentages were 4.6, 8.5 and 18.3 in the epicardial, endocardial part of the left ventricle, and the papillary muscle. There were very significant differences between these 3 mean percentages. There was a very significant correlation between the percentages of scar tissue in the endocardial part of the left ventricle and heart weight. There were no definite correlations between the percentages of scar tissue in the epicardial part or in the papillary muscle and heart weight. From these results, possible causes of scar formation and significance of scar tissue to the development of cardiac failure were discussed.

Quantitative measurement of the ability of human chromophobe adenomas to synthesize and release human growth hormone

A retrospective review of 120 patients undergoing transsphenoidal surgery for pituitary adenomas revealed that computed tomography (CT) was less sensitive and less specific than hormonal methods in identifying residual functioning adenomas, However, CT was the only useful method of evaluating nonfunctioning tumors, including pseudoprolactinomas, Enlargement of the pituitary stalk, when seen on preoperative CT, was 100% predictive of “cure” if the enlargement returned to normal size on a remote follow-up scan (n = 8) and was 100% predictive of residual tumor if the enlargement persisted or evolved (n = 8), Resolution of stalk displacement was the next most reliable predictor of cure (91%, n = 11), but persistent displacement was less reliable than abnormal intrasellar enhancement in predicting the presence of residual tumor (71%, n = 28, vs. 81%, n = 26). Enhancement in the postoperative sella by other than normal pituitary gland was presumed to be due to inflammation in 19% of patients. Inflammatory enhancement was observed in the presence of autograft and homograft muscle plugs and, unlike enhancement due to untreated tumors, was observed to decrease in size and intensity with time. Intrasellar enhancement was an unreliable criterion of success or failure in cases of microadenoma. All 14 patients with functioning adenomas and preoperative parasellar tumor extension had persistent tumor at postoperative evaluation. Of the 47 patients with resected functioning adenomas who had CT scans showing empty or partly empty sellas after operation, 22 (47%) had hormonally detectable residual tumor.