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Biomedical subjects

J F Cooper

Publications and source records attributed to J F Cooper.

At least 37 records · Page 2Linked to original sources
PubMed1983

Purification of acetylcholine receptors from the muscle of Electrophorus electricus.

Muscle from the electric eel Electrophorus electricus contains acetylcholine receptors at 50 times the concentration of normal mammalian muscle and fully one-tenth the concentration of receptors in its electric organ tissue. Receptor is organized much more diffusely over the surface of Electrophorus muscle cells than is the case in normally innervated mammalian skeletal muscle. Receptor was purified from Electrophorus muscle by affinity chromatography on cobra toxin-agarose and found to contain subunits which correspond immunochemically to the alpha, beta, gamma, and delta subunits of receptor from electric organ tissue of Torpedo californica. Receptor purified from Electrophorus muscle appears virtually identical with receptor purified from Electrophorus electric organ tissue.

Animals↗
PubMed1982

Radiotherapy for prostatic carcinoma: post-irradiation prostatic biopsy and recurrence patterns with long-term followup.

From 1968 through 1975, 159 patients with stages A, B and C adenocarcinoma of the prostate were treated with supervoltage radiation therapy. A median dose of 7,200 rad was given. The influence upon survival of grade, stage and a positive biopsy result after irradiation is analyzed. Over-all survival is a patently imprecise test of local treatment because patients die of intercurrent disease and are alive with metastases for significant intervals. The classification of survival with no evidence of recurrent disease excluded those patients dying of intercurrent disease. Therefore, the rate of survival free of disease always will be greater than the over-all survival rate in these patients, and a certain percentage of the patients without evidence of cancer will harbor subclinical disease. The 5 and 10-year survival rates free of disease were 80 and 69 per cent, respectively, in 51 patients with stages A and B cancer, and 66 and 47 per cent, respectively, in 108 with stage C disease. The 5 and 10-year over-all survival rates were 72 and 56 per cent, respectively, in the former and 68 and 39 per cent, respectively, in the latter patients. Survival free of disease and death of prostatic carcinoma were influenced adversely by advancing grade and stage (p less than 0.05), while over-all survival was influenced adversely by grade (p equals 0.02) but not by stage (p greater than 0.05). A positive biopsy result after irradiation did not predict survival free of disease, over-all survival or death of prostatic cancer in patients followed for 10 years (p greater than 0.05).

Adenocarcinoma↗
PubMed1982

Formulae for maximum valid dilution.

The preparation of test specimens using the MVD calculation represents a reasonable approach to equating the sensitivity of the in vitro and in vivo tests for endotoxin. Labeling of LAL reagents and control standard endotoxins are a point of confusion for the parenterals industry. Government and reagent suppliers must work together expeditiously to provide test materials that are explicitly labeled as to reactivity in EU/ml and ng/ml. The relatively greater reactivity of LAL reagent to environmental endotoxin than the rabbit bioassay provides a greater margin of safety for the in vitro approach than previously anticipated, and suggests that rabbit retest of LAL failures may be appropriate for specific products.

Animals↗
PubMed1980

Current experience with radioimmunoassay techniques for prostatic acid phosphatase.

Data are presented demonstrating that radioimmunoassay techniques for measurement of serum prostatic acid phosphatase are more sensitive than enzymatic methods in the detection of all stages of prostatic cancer. The possibility of using a solid phase RIA technique to screen for prostatic cancer is considered. Sixty-three hundred and twenty men over age 45 entering a clinical laboratory for any indication were evaluated using the RIA test for PAP. In this group 444 (7%) had elevated test values. Clinical recall and urologic review of the patients with elevated test results yielded 67 who were suspect for prostatic cancer, of whom 59 (88%) were confirmed by prostatic needle biopsy. These data suggest that the RIA for prostatic acid phosphatase as an isolated clinical procedure is not sufficiently specific to be used for screening due to the large number of false-positive results. However, the RIA-PAP test in combination with a follow-up urologic examination is quite specific and deserves further consideration as a screening method for prostatic malignancy.

Acid Phosphatase↗
PubMed1980

The radioimmunochemical measurement of prostatic acid phosphatase: current state of the art.

A novel radioimmunochemical method for the measurement of human prostatic acid phosphatase in serum and bone marrow has demonstrated distinct biochemical advantages over the standard enzymatic techniques that are currently utilized in the clinical laboratory. The promising nature of the immunochemical assay now in clinical assessment for prostatic cancer may lend itself particularly to more sensitive confirmation of the presence of prostatic neoplasia as well as significantly more precision in the clinical staging of the disease process. In its present form, utilization of the technique as a reliable screening test for early prostatic cancer is patently inappropriate from a biochemical and biostatistical point of view. Continuing research on the antigenic nature of the human prostatic acid phosphatase molecule and the development of antibody with enhanced specificity may somewhat resolve the current screening problem. However, the essentially insoluble problem of the relatively low prevalence rate for prostatic cancer in males in the United States will persist and will probably limit the clinical application of enzymatic and radioimmunochemical screening techniques for early prostatic cancer.

Acid Phosphatase↗
PubMed1979

Combined serum and bone marrow radioimmunoassays for prostatic acid phosphatase.

Combined serum and bone marrow radioimmunoassays for prostatic acid phosphatase provide a unique means for the early diagnosis and more accurate clinical staging of prostatic cancer. The combined screening technique appears to be helpful, particularly in providing a clinical assessment of the presence or absence of early, subclinical lymphatic and bone marrow metastases. Low titer elevations of bone marrow prostatic acid phosphatase by radioimmunoassay have been observed commonly in clinically understaged C prostatic cancer with normal technetium bone scans, indicating the presence of unrecognized stage D disease with bone metastases. The combined screening method also is of distinct clinical value in the early diagnosis of prostatic cancer and in monitoring the effects of specific therapy. In therapeutically responsive patients marked suppression of serum and bone marrow prostatic acid phosphatase is observed regularly with the radioimmunochemical method under study.

Acid Phosphatase↗
PubMed1978

Excessive proliferation of peripelvic fat of the kidney.

Excessive proliferation of the peripelvic fat of the kidney (EPPF) is a benign process with an innocuous effect on the patient. However, this condition may assume major clinical significance by producing pyelocalyceal deformities that may be mistaken for true renal masses. Rarely, EPPF may masquerade as a renal pelvic tumor. We present the second reported case of EPPF simulating a renal pelvic tumor and review the history as well as the characteristic radiographic and sonographic features of this condition.

Adipose Tissue↗
PubMed1978

A solid phase radioimmunoassay for prostatic acid phosphatase.

The sensitivity of a recently developed solid phase radioimmunoassay for human prostatic acid phosphatase was compared to that of an enzymatic method using p-nitrophenylphosphate as substrate. In 109 histologically verified untreated stages I to IV prostatic cancers and 200 men without such cancer the solid phase radioimmunoassay method demonstrated substantially greater sensitivity and specificity than the enzymatic technique. In the 109 prostatic malignancies the immunochemical method correctly classified 80 (73 per cent) versus 34 (31 per cent) for the p-nitrophenylphosphate enzymatic technique (p less than 10(-6). In 44 stages I and II cancers confined to the prostate the radioimmunoassay was abnormally elevated in 19 (43 per cent) with only 4 (9.1 per cent) enzymatic elevations (p less than 10(-3). In 65 stages III and IV extraprostatic cancers correct classifications were noted in 61 (94 per cent) of the radioimmunoassays and 30 (46 per cent) enzymatic tests (p less than 10(-6). The radioimmunoassay in 200 male controls yielded 11 (5.6 per cent) and the p-nitrophenylphosphate enzymatic test yielded 7 (3.5 per cent) falsely positive results. In 90 non-prostatic human cancer sera 85 (94.5 per cent) were correctly classified as negative by the radioimmunoassay for prostatic acid phosphatase versus 66 (73 per cent) as negative by the enzymatic method. These data are discussed in terms of the merits of a radioimmunochemical approach for the measurement of human serum prostatic acid phosphatase.

Acid Phosphatase↗
PubMed1978

Radioimmunochemical measurement of bone marrow prostatic acid phosphatase.

Human acid phosphatases are ubiquitous phosphohydrolases that are present in most respiring tissues and cells. Specifically, human prostatic acid phosphatase is a unique enzyme within a vast family of acid phosphatases concerned with catabolic processes in cellular metabolism. The majority of serum and bone marrow acid phosphatases are of non-prostatic origin and are present chiefly in erythrocytes, leukocytes, platelets and other maturing cells in the bone marrow. The specific concentration of prostatic acid phosphatase in serum and bone marrow is normally relatively low compared to non-prostatic acid phosphatases. Many falsely positive assays for total serum acid phosphatases and bone marrow acid phosphatases have been reported, particularly after traumatic marrow biopsy procedures and mishandling of blood samples in the clinical laboratory and in hematologic disease states. The disruption and lysis of whole blood and marrow cells can liberate non-specific acid phosphatases into the serum. Since standard enzymatic assays do not discriminate accurately prostatic acid phosphatase from non-prostatic acid phosphatase present in the serum spurious results can be realized. A preliminary experience with a promising radioimmunoassay for the specific measurement of prostatic acid phosphatase in bone marrow and serum is presented.

Acid Phosphatase↗
PubMed1978

The natural history of papillary transitional cell carcinoma of the bladder and its treatment in an unselected population on the basis of histologic grading.

Between 1950 and 1965, 365 patients were treated for transitional cancer of the bladder at our hospitals. A retrospective study was done, using clinical records and a histopathologic review to determine the long-term natural history of this population when treated conservatively. The natural history of 3 separate patient populations was discovered, based solely on the grading of the transurethrally resected fragments. Based on the grade on initial presentation these patients were divided into grades I, II and III. Of the patients 5 per cent in grade I, 16 per cent in grade II, 28 to 35 per cent in grade III not involving muscle and 83 per cent in grade III involving muscle died of bladder cancer. Ninety-seven patients (26 per cent) died of bladder cancer, 110 (31 per cent) died of other causes and 158 (43 per cent) have been alive more than 5 years (104 more than 10 years). Grade I tumors that progressed to a higher grade did so within 2 years of the initial diagnosis. Of the bladder cancer deaths 83 per cent occurred within 2 years of the initial diagnosis. Of 64 patients dying more than 5 years after presentation only 7 died of bladder cancer.

Biopsy↗
PubMed1978

Measurement of prostatic acid phosphatase in various cell lines.

In the last few years, we have developed a radioimmunoassay for the measurement of human prostatic acid phosphatase. This method, which requires samples of the patient's serum, has been proved to be more accurate than the conventional enzymatic assay for the detection of early stages of carcinoma of the prostate. We used the enzymatic assay and radioimmunoassay for the quantitation of prostatic acid phosphatase in cultured prostatic cell lines. We were unable to show any difference in the concentration of prostatic acid phosphatase between prostatic and any other established cell lines.

Acid Phosphatase↗
PubMed1978

Counterimmunoelectrophoresis in determination of prostatic acid phosphatase in human serum.

We evaluated counterimmunoelectrophoresis for use in measuring prostatic acid phosphatase in detection of prostatic cancer. After staining for acid phosphatase, we could detect as little as 0.3 ng of purified enzyme standard complexed with antibody by this technique. However, when serum samples were used as antigen, the method was less sensitive (1.5-2.0 ng) because some of the serum proteins migrate with the phosphatase and decrease the intensity of the stain for acid phosphatase. For this reason we could not detect the phosphatase in serum samples of normal persons; only patients with moderately (or greater) increased activity in their serum showed positive results. In contrast, by radioimmunoassay as little as 1.0 ng of the phosphatase can be detected in serum.

Acid Phosphatase↗