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H Herschman

Publications and source records attributed to H Herschman.

28 records · Page 2Linked to original sources
PubMed1977

Comparison of human prostatic acid phosphatase by measurement of enzymatic activity and by radioimmunoassay.

We compared results of measurement of prostatic acid phosphatase activity in serum and various tissues by enzymatic assay and radioimmunoassay. By enzymatic assay, activity in serum is lost rapidly, even at room temperature. In contrast, there was no change in antigenic activity during 48 h by radioimmunoassay. The radioimmunoassay was more specific in 12 tissues and in serum than were several enzymatic assays that make use of inhibitors of the enzyme. The enzymatic assay resulted in 26.6% (24/90) false positives from non-prostatic cancer patients. In contrast, with radioimmunoassay there were only 5.5% (5/90) false positives. We conclude that immunological detection of prostatic acid phosphatase is the more reliable technique.

Acid Phosphatase↗
PubMed1977

Isozymes of acid phosphatase in normal and cancerous human prostatic tissue.

The supernatants of the homogenates from normal and cancerous human prostatic tissue run on polyacrylamide gel electrophoresis have 2 major electrophoretic bands when stained for prostatic acid phosphatase. The ratios of the electrophoretically distinguishable isoenzymes differ in normal and cancerous tissues. Similar distinctions between isoenzymes in normal and cancerous prostates are observed following column chromatographic separation or isoelectric focusing. The faster electrophoretic band can be separated by diethylaminoethyl cellulose column chromatography or by isoelectric focusing into at least five fractions with different electrophoretic mobilities. We could not find any differences in normal and cancerous tissues among these subfractions of the faster-moving electrophoretic band. Analysis by gel electrophoresis does not show association between these fractions after chromatographic or isoelectric separation of the prostatic acid phosphatase fractions. Quantitative, but no qualitative, differences in prostatic acid phosphatase isozymes occur in normal versus cancerous prostates.

Acid Phosphatase↗
PubMed1976

Epidermal growth factor enhancement of skin tumor induction in mice.

Subcutaneous injection of epidermal growth factor 1. significantly shortened the latency period for the appearance of methylcholanthrene induced skin tumors and 2. increased the average number of papillomas elicited per mouse in both the Swiss Webster and C3HeB/FeJ strains.

Animals↗
PubMed1975

Effects of nerve growth factor administration of N-ethyl-N-nitrosourea carcinogenesis.

We attempted to determine whether the sympathetic nervous system in rodents is susceptible to co-carcinogenesis, employing murine salivary nerve growth factor (NGF) as a co-carcinogenic agent. NGF had no co-carcinogenic effect with either methylcholanthrene or ethylnitrosourea (ENU) on the sympathetic nervous system of the mouse, whether administered transplacentally, postnatally, or both transplacentally and postnatally. At a dose of ENU of 30 mug/g body weight, NGF did not shorten the latent period for tumor induction of BD-IX rats. In contrast, a 25% reduction in latent period was brough about by NGF for tumor appearance in BD-IX rats receiving 90 mug/g ENU. In both cases the frequency of urogenital tumors in rats was increased as a result of NGF administration, at the apparent expense of neural tumors.

Animals↗
PubMed1975

A solid-phase radioimmunoassay for human prostatic acid phosphatase.

A solid-phase technique for radioimmunoassay of human prostatic acid phosphatase (EC 3.1.3.2) is described. Human prostatic acid phosphatase was purified from prostatic fluid. Monospecific antisera to the purified acid phosphatase were produced in rabbits. Disposable polypropylene tubes were coated with antiserum and used for radioimmunoassay with 125I-acid phosphatase. The nonspecific binding was minimized by saturating the binding sites of the tubes with bovine serum albumin. The working range of the technique was 1 to 30 ng of antigen. The solid-phase radioimmunoassay is rapid, sensitive, and efficient. In preliminary clinical trials it was shown that (a) patients with advanced prostatic cancer had elevated prostatic acid phosphatase levels by both enzymatic assay and radioimmunoassay assays, and (b) patients with other cancers were in the normal range for prostatic acid phosphatase.

Acid Phosphatase↗
PubMed1975

Enhancing effect of surfactant and protein on hydrolysis of thymolphthalein monophosphate by purified prostatic acid phosphatase.

Purified prostatic acid phosphatase catalyzes the hydrolysis of thymolphthalein monophosphate 10-fold faster if an optimal concentration of Brij 35 (a wetting agent) or protein (bovine serum albumin or human serum proteins) is present. Results of gel filtration, dialysis, and sucrose density-gradient centrifugation analysis suggest that the substrate must combine with detergent or protein before the enzyme can catalyze its hydrolysis.

Acid Phosphatase↗