Altered collagen composition in a prolapsing mitral valve with ruptured chordae tendineae

A patient presented with mitral valve prolapse, ruptured chordae tendineae, severe mitral regurgitation and congestive heart failure. Pathologic studies demonstrated myxomatous changes of both mitral leaflets. Collagen analysis of the valve and of the chordae tendineae revealed the presence of type I collagen in normal quantities and a striking absence of type III and AB collagens. The altered collagen in this patient's mitral valve probably contributed to the development of his mitral valve disorder.

Sebaceous carcinoma of the eyelid following radiation therapy

This paper reports a case of a 12-year-old boy with fatal sebaceous carcinoma originating from the eyelid. The carcinoma developed 11 years after curative radiation therapy for bilateral retinoblastoma. Sebaceous carcinomas associated with previous irradiation are uncommon, and only five such cases have been published. Three of the patients were treated for benign disorders and the two other cases followed radiation therapy for bilateral retinoblastoma. Second malignant neoplasms in patients with bilateral retinoblastoma are thought to be related to a genetically inherited predisposition to the development of second malignant tumors. Radiation therapy is claimed to be an inducing factor in many cases but malignant neoplasms are also found in areas distant from the portals of irradiation as well as in patients not irradiated. Most of the secondary tumors were sarcomas, and usually osteogenic sarcomas.

Endomyocardial fibrosis with calcification of the myocardium

A case of endomyocardial fibrosis with intramyocardial calcification was characterized by symptoms of restrictive cardiomyopathy resembling constrictive pericarditis. Pathological findings were typical of those found in classical Davies' disease, originally encountered and described in Uganda.

Radionuclide liver spots: indicator of liver disease or a blood flow phenomenon

Abnormal areas of increased uptake on liver scan have been controversial. While often said to be associated with superior vena caval obstruction, three distinctly different findings are possible: hot spot, warm spot, and no spot. All of these changes can be readily explained by distinct, separate anatomic venous collateral pathways. Four cases of superior vena caval obstruction with isotopic liver flow studies are presented. Anatomy of the venous collateral system is reviewed, and the potential significance of the liver "warm spot" is considered.

Mechanisms of cellular enzyme release. II. Inhibition of sarcolemmal enzymes by myopathy-inducing agents

A defective membrane mechanism has been suggested [Arch. Neurol. 33, 315 (1976)] for the pathogenesis of Duchenne muscular dystrophy. The characteristic clinical and biological findings, including leakage of cellular enzymes into the serum in the disease, have been duplicated by the imipramine/serotonin rat myopathy model. Sarcolemma was prepared from quadriceps femoris muscles of control and myopathy-affected animals. The activities of sarcolemmal adenosinetriphosphatase and acetylcholinesterase were inhibited in vitro by imipramine and serotonin. The inhibition by imipramine of these sarcolemma-bound enzyme systems decreased the Vmax and increased the Km. This mixed type of inhibition is consistent with an imipramine-induced interference at these enzyme sites and a disruption of lipid-protein interrelations. We hypothesize that such conformational membrane changes might contribute to the leakage of macromolecules such as enzymes from the cell interior.

Mechanisms of cellular enzyme release. II. Inhibition of sarcolemmal enzymes by myopathy-inducing agents

A defective membrane mechanism has been suggested [Arch. Neurol. 33, 315 (1976)] for the pathogenesis of Duchenne muscular dystrophy. The characteristic clinical and biological findings, including leakage of cellular enzymes into the serum in the disease, have been duplicated by the imipramine/serotonin rat myopathy model. Sarcolemma was prepared from quadriceps femoris muscles of control and myopathy-affected animals. The activities of sarcolemmal adenosinetriphosphatase and acetylcholinesterase were inhibited in vitro by imipramine and serotonin. The inhibition by imipramine of these sarcolemma-bound enzyme systems decreased the Vmax and increased the Km. This mixed type of inhibition is consistent with an imipramine-induced interference at these enzyme sites and a disruption of lipid-protein interrelations. We hypothesize that such conformational membrane changes might contribute to the leakage of macromolecules such as enzymes from the cell interior.

The prognostic significance of lymphocytic infiltration in malignant melanoma of the choroid

Lymphocytic and plasmocytic infiltration surrounding a malignant tumor probably represents an immunologic response of the host directed against the neoplasm. It has been documented that lymphocytic infiltration has a favorable effect on prognosis in a number of human tumor systems, including cutaneous melanoma. In the present study, 309 consecutive cases of choroidal melanoma were examined for cellular infiltration, and these data were correlated with other histologic parameters and with prognosis. A intense cellular infiltration was found in 15 tumors (4.9%) and a moderate infiltration in 37 (12.0%). Tumors with cellular infiltration were significantly larger and more vascularized than the remaining tumors, which may be related to the accessibility of the immune system to the tumor. There was a higher percentage of poorly differentiated tumors among the tumors with cellular infiltration. However, it does not appear the cellular infiltration favorably influences the prognosis of choroidal melanoma. The 5-year survival rates of patients with like cell types did not depend upon the degree of cellular infiltration demonstrated by the primary tumor. Although choroidal melanomas are capable of inciting an immune response, this response is apparently ineffective in preventing metastatic spread.

Clindamycin-induced pseudomembranous colitis. Report of three cases

Three cases of Clindamycin-induced pseudomembranous colitis are reported. Special attention is focused on histology in the description of the lesions and their recovery in reference with radiologic findings.

Immunofluorescence and immunoperoxidase observations of anti-lactic dehydrogenase-1 antibody

For immunoelectron-microscopic demonstration of lactic dehydrogenase (LDH), anti-subunit-B antibody was produced in rabbits by immunization with purified pig LDH-1 (B4) isoenzyme. Immunoglobin fragment Fab' was obtained from anti-LDH serum immunoglobulin G and conjugated with horseradish peroxidase. Subunit-B-containing LDH was present diffusely in the sarcoplasm of the pig heart muscle. There was concentration of LDH in the 1-band. LDH reaction was also present in the mitochondrial intermembranous space. The present immunoelectron-microscopic examination is in general agreement with the previous cytochemical demonstration of LDH using thiocarbamylnitro blue tetrazolium.

Influence of heart rate and age on Q-Korotkoff sound intervals

The Korotkoff sound appearance time (QK intervals) was measured in 224 normal subjects of both sexes between the age of 6 and 79 years. The sex difference was not obvious except for the diastolic values of the intervals (QKd) in the sixth decade. Although the QK intervals remained almost unchanged between the third and the fifth decade, both the systolic (QKs) and the diastolic values were significantly smaller in the young subjects under the age of 20. On the other hand, QKs was significantly decreased and QKd and the difference between the systolic and diastolic values (QKs-d) were significantly increased in the elderly subjects. The short QK interval in the young subjects was considered to be mainly attributable to the short preejection period, while the increased pulse wave velocity was postulated to be the main responsible factor for the shortening of QKd in the elderly subjects. A statistically significant negative correlation was demonstrated between QKd and the heart rate in both sexes, while QKs and QKs-d were not significantly correlated with the heart rate.

Pathology of atherosclerotic heart disease in sudden death. II. The significance of myocardial infarction

The role of myocardial infarction was investigated in 121 cases of sudden death with atherosclerotic heart disease. In addition to supporting other reports which have demonstrated the importance of chronic occlusion of the coronary vessels in relation to the high rate of infarctions found in such cases, the authors presented evidence which showed differences in occurrence in the sites of remote and recent infarctions, a lack of concordance between the sites of recent infarctions, and acute thrombosis in coronary vessels proximal to these lesions. No relationship between patient age or prior symptoms could be associated with the occurrence of infarction. Evidence was also presented which discounted the possible role of transmural infarction in the formation of acute thrombosis. These pathological observations support the concept that sudden cardiac deaths are results of functional instability of the myocardium produced by advanced coronary atherosclerosis.

Pathology of atherosclerotic heart disease in sudden death. I. Organizing thrombosis and acute coronary vessel lesions

The significance of organizing thrombosis was investigated in 121 cases of sudden death with atherosclerotic heart disease. Organizing thrombosis was observed in one-third of the cases, and sites at which it was present showed a higher prevalence of acute lesions -- thrombus, plaque rupture, and hemorrhage -- than sites at which it was not present. Acute and subacute coronary lesions were almost entirely restricted to vessels with 75% or greater obstruction. Evidence was presented suggesting that the organization of thrombosis in the coronary arteries was a more extended process than that observed in peripheral arteries.

Thrombotic calcific mitral stenosis. Morphology of the calcific mitral valve

We compared the morphology of the calcific stenotic mitral valve (CSMV) with noncalcific stenotic mitral valves (NCSMV) removed at surgery; control valves were obtained at autopsy. X-rays of the excised valves permitted localization and quantitation of calcification. A classification of CSMV applicable to noninvasive techniques based on this methodology is presented. Moderate to heavily CSMV had greater weight, volume, specific gravity, weight per area, with smaller orifice size when compared with NCSMV and controls. Leaflet mobility was obliterated in moderate to heavily CSMV, while most NCSMV had some degree of leaflet mobility.

Surface morphology was strikingly different in CSMV with 1) surface ulceration , due to eruption of the underlying calcific focus through valvular endothelium, 2) thrombosis in the areas of ulceration ( associated with symptomatic arterial embolization in four patients), 3) whisker formation , filamentous stalks along the line of valve closure.

Calcification in the CSMV is viewed as an active, progressive process resulting in altered physical characteristics of the valve, progressive leaflet immobility and orifice narrowing, and eruptive surface changes with thrombus formation and arterial embolization arising from the CSMV itself. Clinical implications and a rationale for more precise classification of mitral stenosis on the basis of valvular calcification are presented.

Animal model: spontaneous adenocarcinoma in aged rabbits

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