Béla Halpert

Cells grown on isolated intravascular dacron hub: An electron microscopic study☆

Abstract Dacron hubs anchored by polyethylene sutures in the center of vascular prostheses were placed in the thoracic aortas of growing young pigs and adult dogs. This permitted cells in the blood-stream to settle, grow, and differentiate on the hub. The nature of the cells was studied by special histologic techniques and electron microscopy. Endothelial cells covered the hub. Between the endothelium and the dacron, and close to the dacron, there were giant cells of the foreign body type. Beneath the endothelium there were fibroblasts and smooth muscle cells. The covering of the hub was identical to the inner lining of the dacron vascular prosthesis to which the hub was anchored.

Carcinoma of the prostate in patients 70 to 79 years old

On step cross sections of the entire prostate gland in 100 patients aged 70 to 79, carcinoma was identified in 41. Of these, 17 were diffuse and 24 were focal. The site of origin of the diffuse carcinomas could not be ascertained though one half of the gland usually was involved more extensively. The location of focal carcinomas was usually at the periphery of the gland. While the microscopic patterns of diffuse and focal carcinomas were reasonably distinct, it appears that their biologic behavior is similar, and that focal carcinoma may be a stage in the development of diffuse carcinoma of the prostate.

Endothelial Lining of Dacron Prostheses of Porcine Thoracic Aortas.

Summary Prostheses of knitted, crimped dacron, some with and some without gelatin impregnation, were placed in the thoracic aortas of 17 young pigs. The prostheses replaced excised segments of aortas, 4 to 6 cm long, and were left in place for 7 to 139 days. “En face” and pellicle silver preparations revealed complete endothelial covering of the surface of a prosthesis after 7 days.

LINING OF AUTOGENOUS VEIN PATCH GRAFTS OF SMALL CANINE ARTERIES.

Summary The inner lining of autogenous vein patch grafts placed into small canine arteries by microsurgical techniques was studied. The grafts placed in 22 femoral arteries of 13 dogs were kept in place from 2 days to 76 weeks. Aortography disclosed patency of all the arteries grafted with no or slight dilatation at the site of operation. En face silver preparations disclosed that the intimal surfaces of the grafts were covered with endothelium after the 4th day. Endothelial cells were demonstrated in pellicle preparations. The patch contributed its own substance, particularly elastic fibers, to the repair of the arterial wall.

Experimental Evaluation of a Marlex Vascular Prosthesis.

Summary A vascular prosthesis of Marlex was implanted as a long aortic bypass graft in dogs and left in place up to 12 months. After 3 months of implantation, the inner surface of the prosthesis had a smooth lining and was firmly attached through the interstices to the periprosthetic tissue. None of the implanted prostheses exhibited stenosis, aneurysm or plaque formation. The inner and outer surfaces of the fabric were covered by a band of hyalinizing fibrous connective tissue. Plaques of osteoid were numerous on the intimal surface. Although the Marlex prosthesis functions adequately as a vascular substitute, unsatisfactory physical properties of this material limit its clinical use.

Sodium and potassium concentrations in bile from human gallbladders.

Summary Measurements of sodium, potassium, pH, total solids and pigment in human gallbladder bile indicate wide variations. Potassium is present in higher concentrations than in extracellular fluids. The resorptive power as measured by pigment failed to correlate with the increase in potassium concentration and total solids.