Biomedical subjects
Publications and source records attributed to B S Levowitz.
The clinical and pathologic features of a case of adrenal carcinosarcoma are reported. Although synchronous malignancy of the adrenal gland has been described, no case of an adrenal tumor combining both carcinomatous and sarcomatous elements has been previously documented. This neoplasm is extremely aggressive with distant metastasis arising from the sarcomatous component, and rapid progression despite multimodal therapy.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Human umbilical cord vein allografts (HUCVAG) were prepared by sequential treatment of fresh cords with 95 percent ethanol and 1.3 percent dialdehyde starch. Twenty-six of 30 canine aortic implants of fully treated grafts were patent at the end of 8 months. Among 25 aortic interpositions of untreated and 70 percent ethanol-treated grafts, the mean survival was 13 and 34 days, respectively. Five of ten 70 percent ethanol:1.3 percent dialdehyde starch-treated implants remained patent for 8 months. Graft failure was attributed to incomplete antigenic suppression manifested by rejection changes, including thrombosis, anastomotic disruption, aneurysm formation, and intimal degeneration. HUCVAG has been used in five patients who required femoropopliteal bypass. Of three successful revascularizations, two remain patent beyond 8 months without aneurysm formation. These results suggest that the processed, valveless, unbranched HUCVAG, in unlimited supply, may serve as an available alternative in the absence of a suitable saphenous vein.
Hydrostatic dilation and moist heat applied postoperatively are methods that enhance blood flow in side-to-end radial artery to cephalic vein arteriovenous fistula. This improves early patency of the fistula with marginal sized outflow.
From 1954 to 1970, ninety-five patients with medullary carcinoma of the breast were evaluated in terms of immunologic activity based on the histologic changes seen within the tumor and regional nodes. Each patient was studied for the degree of lymphocytic infiltration in the tumor as well as the extent of sinus histiocytosis present within the regional nodes. Contrary to what would normally be expected, those nodes with increased sinus histiocytosis were associated with the larger tumors. In addition, lymph node metastasis increased from 26 to 75 per cent as the degree of sinus histiocytosis became more pronounced. There was no evidence that increased lymphocytic infiltration in the tumor resulted in a statistically significant improvement in the five and ten year survival rates. Similarly, sinus histiocytosis activity did not seem to enhance the survival rate among this particular group of patients. There is a suggestion that a correlation exists between sinus histiocytosis and lymphocytic infiltration in the tumor and that, whatever the stimulus present, its effect is on both the lymph node and the degree of lymphocyte response within the tumor. The antigenic substance in the tumor, which initiates the immune response, possibly produces an abortive reaction, which may result in the induction of blocking factors rather then those factors necessary for destruction. It appears that histologic evidence of immunologic enhancement does not necessarily signify improved survival, at least with those patients having carcinoma of the breast.
Vascular access through subcutaneous prosthetic arteriovenous fistulas was studied in eighteen dogs. Dacron velour and woven Dacron grafts (6 mm diameter) were constructed across the lower abdomen between the common femoral artery and the opposite common femoral vein. In heparinized animals 197 percutaneous punctures were made with a "14 guage hemodialysis cannula at weekly intervals. Over a period of one and a half years there was no instance of infection. One of the fourteen Dacron velous and all four woven Dacron fistulas thrombosed. These data suggested the feasibility of achieving repetitive blood access through Dacron velour vascular prostheses. Nineteen Dacron velour fistula bypasses between the brachial artery and median basilic vein were performed in fifteen selected patients for a total dialysis period of ninety-six months. Failed standard subcutaneous fistulas or absence of suitable vessels in the upper extremity were indications for the primary procedure. Of three looped forearm fistulas, two thrombosed at twenty-two and two months. Complications among sixteen straight bypasses in the arm included two graft infections and one cannula tract infection. There were no instances of thrombosis in this group. The advantages of single needle dialysis in these high risk patients have been emphasized. Eleven grafts are presently functioning two to nine months postoperatively. Our preliminary results suggest that a Dacron velour fistula merits consideration as an alternative for vascular access in maintenance hemodialysis.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Pulmonary blastoma is a rare primary malignancy of the lung originating from multipotential pulmonary blastema. Two cases of this tumor are reported emphasizing lack of correlation between the microscopic appearance and the clinical course. There are no specific clinical features that differentiate this tumor from the more common lung neoplasms. Surgical resection is the preferred treatment; the merits of radiotherapy and chemotherapy have not yet been established. Prognosis after adequate resection appears no better than for other pulmonary malignancies.
Explore the source record for details and available documents.
Human umbilical cord vein allografts (HUCVAG) were modified by sequential treatment with 95% ethanol and 1.3% dialdehyde starch and stored in 70% ethanol. Tensile strength measurements of HUCVAG were found to range between canine aorta and bovine heterograft. Surface clotting was prolonged to 4 times that of pre-clotted dacron velour and 2 times that of bovine carotid heterograft. Inferior vena cava implants of HUCVAG remained patent for a period of 10 to 14 days while 4 of 5 bovine carotid heterografts clotted in 2 hrs ans one within 3 days. Micrpscopic examination showed a smooth intimal surface with no fibrin deposition and no evidence of rejection, providing excellent basic qualities as a vascular substitute. Using "14 gauge cannula, 180 repetitive percutaneous punctures were made in 10 heparinized dogs with HUCVAG fistulas between the carotid artery and external jugular vein. With exception of one instance in any preparation over a 4 month period. These results suggest the valueless. unbranched modified umbilical cord vein in unlimited supply is suitable as an arteriovenous fistula for blood access in maintenance hemodialysis.
In the present study, 23 of 314 patients presented with asymptomatic lesions in the second breast, comparing favorably with the incidence of asymptomatic carcinomas of the second breast reported in other series. The type of biopys used appears important, most surgeons advocating resection of a segment of breast ranging from 20 to 30 per cent of the quadrant being sampled. It appears that treatment of carcinoma of the second breast is essentially curative when the lesion is not noted clinically. Adequate treatment of the second breast lesion appears to reduce the at risk group within the second breast. It is usually stated that 10 per cent of patients will have a second carcinoma of the breast develop. In this study, metachronous lesions developed in six of 291 patients. Considering that these tumors all recurred in the outer quadrant of the remaining breast, the possibility arises that it may be more productive to do all biopsies in the tail of the second breast rather than to perform the so-called mirror image biopsy that was used in the present study. Results from this and other studies do appear to indicate that the utilization of a mirror image biopsy or outer quadrant biopsy is an effective way to detect and treat occult malignant tumors as well as the earliest forms of premalignant disease.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.