Biomedical subjects

P Tomashefsky

Publications and source records attributed to P Tomashefsky.

8 recordsLinked to original sources

PubMed1979

Bone marrow acid phosphatase in prostate cancer: an assessment by immunoassay and biochemical methods.

Comparisons of the bone marrow and serum acid phosphatase values obtained by counterimmunoelectrophoresis and the Roy biochemical test were made in 72 patients with and in 13 patients without prostatic cancer. The counter-immunoelectrophoresis test, when positive at more than 1 international unit per liter, showed only 4.4% falsely positive results. The Roy biochemical test, which uses sodium thymolphthalein monophosphate as the substrate, had 65% falsely positive bone marrow acid phosphatase levels. Conflicting reports regarding the value of bone marrow acid phosphatase determinations in patients with prostatic cancer result from the use of non-specific substrates in biochemical methods for measurement and from the trauma incidental to bone marrow aspiration, which releases many non-prostatic acid phosphatase enzymes. The use of immunoassay such as counter-immunoelectrophoresis minimizes this source of error.

Acid Phosphatase↗

PubMed1978

Counter immunoelectrophoresis for detection of human prostatic acid phosphatase.

An immunochemical method for detection of prostatic acid phosphatase is described. Acid phosphatase was obtained from benign human prostatic tissue. A specific antiserum to this enzyme was produced in rabbits. A counter immunoelectrophoretic method utilizing the specific antiserum with a chemical staining technique has been developed. Clinical trials have indicated the usefulness of this method for the specific determination of prostatic acid phosphatase.

Acid Phosphatase↗

PubMed1977

The direct effect of ultrasound upon Wilms' tumor in the rat.

The possible activation of immunologic defenses against tumor by local ultrasonic irradiation was investigated. Sonication of one tumor of a dual implant destroyed that tumor only with no contralateral effect. Injection of tumor cells previously sonicated in vivo did not induced immunity to subsequent challenge with live cells. Immunofluorescent staining of host kidneys for antibody complexes was negative. It was concluded that sonication was only effective when directly applied to the tumor.

Animals↗

PubMed1976

Interaction of ultrasound with neoplastic tissue: IV. alteration of biologic activity in cells derived from rat Wilms' tumor sonicated in vivo.

Paired Wistar-Furth male rats were implanted subcutaneously with the Furth-Columbia rat Wilms' tumor. Seven days after implantation the tumors were either subjected to therapeutic ultrasound irradiation or were left as untreated controls. On the ninth day after implantation the animals were sacrificed, and suspensions of cells were made from the excised tumors by trypsinization. The cells were counted using trypan blue dye as an indicator of viability. New rats were then implanted with cells either from sonicated tumors or cells from controls. In half the recipient animals the suspensions were matched by total cell count. In the other half of the rats cell counts were matches for viability by the dye exclusion test. Tumors developed in a total of 8 of 11 rats receiving control cells and they died. A palpable tumor did not develop in any rat receiving cells fromsonicated tumors during the ninety-day study period. Surviving rats were challenged with Wilms' tumor by trocar implant. Tumor developed in all recipients, and they died.

Animals↗

PubMed1976

Interaction of ultrasound with neoplastic tissue. II. Systemic effects after local sonic irradiation.

Local sonic irradiation was applied to subcutaneously implanted Furth-Columbia rat Wilms' tumor. The weight and the rate of tritiated thymidine uptake were measured in host organs distal to the application field. Kidney and spleen weights were inhibited by the Wilms' tumor, and sonication of the tumor removed all or part of this inhibition. Liver weight was increased after sonication of tumor-bearing rats but not in nontumor-bearing rats. This may have been a response to tumor-specific substances released into the circulation by sonic destruction of tumor tissue. The adrenals enlarged as a response to the stresses of both tumor-bearing and of sonication. Animals were implanted on both sides with the Wilms' tumor and on without any break in the growth curve while the sonicated right tumor was inhibited. These data suggest that the therapeutic effect of ultrasound is due solely to local factors and that systemic sequelae of some irradiation are unrelated to tumor inhibition.

Adrenal Gland Neoplasms↗

PubMed1976

A murine Wilms' tumor as a model for chemotherapy and radiotherapy.

We studied the effect on tumor volumes and host survival of twenty-four chemotherapeutic and radiotherapeutic regimens in rats bearing the Furth/Columbia murine Wilms' tumor. After 5 years and some 100 transfers, this tumor retained its sensitivity to suitable combinations of actinomycin D, vincristine, and X-ray, regimens in current use in the treatment of human Wilms' tumor. Cytoxan alone was highly inhibitory; adriamycin was modestly inhibitory; and lethal doses of methotrexate followed by leucovorin "rescue" were slightly inhibitory to the growth of the rat tumor. No other chemotherapeutic agent tested was effective by our criteria. Cytoxan, with or without adriamycin, and X-irradiation, were the most useful combinations studied. The chemotherapeutic agents given 3 days before irradiation were significantly more carcinostatic than they were when given after radiotherapy.

Animals↗

PubMed1976

Interaction of ultrasound with neoplastic tissue. III. Electron microscopic demonstration of ulstrasonic destruction of Wilms tumor and its cellular membranes.

Exposure of 300 adult, male Wistar-Furth rats bearing subcutaneous implants of Wilms tumor to a vertically oriented planar ultrasound beam consistently resulted in a marked decrease in the growth rates of the tumors with an increase in the survival times of the treated animals. Grossly, the local effects consisted of a flattening of the tumors with clean excavation of their bases. Histologically, a line of demarcation was demonstrated between the sonicated (or destroyed) and non-sonicated portions of the same rat Wilms tumors. The sonicated portions exhibited a complete loss of the normal spatial relationship between the tumor epithelium and its surrounding mesenchyme. Ghost residuals of portions of individual cytoplasmic cell borders and nuclei with condensed chromatin patterns still could be discerned. Electron microscopy demonstrated a marked destruction of the nuclear and cytoplasmic cellular membranes with a migration of destroyed condensed chromatin material into the surrounding cytoplasm.

Animals↗

PubMed1975

Interaction of ultrasound with neoplastic tissue. Local effect on subcutaneously implanted Furth-Columbia rat Wilms' tumor.

Ultrasonic irradiation was employed by direct administration to the skin overlying subcutaneously implanted Furth-Columbia rat Wilms' tumors. Treated tumors were flattened and excavated and demonstrated no stigmata of hemorrhage or infection. There was a marked decrease in growth rate of the tumors with an increase in survival time of the host. Histologic assessment with the light microscope exhibited a sharp line of demarcation between the necrosed sonicated portion of tumor and the viable intact nonsonicated area of tumor. A blackened area of skin, which was not histologically similar to a burn, was interposed betwwen the site of application of the ultrasound and the necrosed tumor.

Animals↗