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Biomedical subjects

J D Schmidt

Publications and source records attributed to J D Schmidt.

At least 73 records · Page 4Linked to original sources

Placenta-like isoenzyme of alkaline phosphatase in prostatic cancer.

Assays for serum placenta-like (Regan) isoenzyme of alkaline phosphatase were done on 157 samples from 96 patients with prostatic cancer entered into various National Prostatic Cancer Project protocols. Elevated placenta-like isoenzyme levels were found in 19 patients (20 per cent). Increased isoenzyme activity was seen in some patients with early clinical stages of the disease (B1 and B2), as well as in those with advanced disease. As in other reports results were not consistent in any individual patient. No correlations could be made between elevated isoenzyme activity and either stage of the disease or response to therapy. The placenta-like isoenzyme of alkaline phosphatase appears to be a nonspecific oncodevelopmental marker that is not helpful alone as a diagnostic indicator but that may be promising as part of a profile of markers for a patient with prostatic cancer.

Alkaline Phosphatase↗

The value of nuclear bone imaging in advanced prostatic cancer.

The nuclear bone scan is a highly sensitive means of detecting skeletal metastasis in patients with prostatic cancer. Serial bone imaging provides an accurate method to follow the response of osseous metastases to treatment and to detect relapsing disease in the skeleton. In selected instances the nuclear bone scan can provide information about vertebral metastases that can be important for planning palliative treatment of pain.

Bone Neoplasms↗

Comparison of estramustine phosphate and vincristine alone or in combination for patients with advanced, hormone refractory, previously irradiated carcinoma of the prostate.

There were 121 men with hormonally refractory metastatic cancer of the prostate who were randomized to receive estramustine phosphate or vincristine, or the combination of these 2 agents. All patients had received prior radiation therapy (greater than 2,000 rad). There were 90 patients who could be compared for response. The objective response rates (partial regression or stabilization of disease) for the 3 treatment groups were 26 per cent for estramustine phosphate, 24 per cent for estramustine phosphate plus vincristine and 15 per cent for vincristine. Subjective parameters varied little among the 3 regimens. The median duration of response for those responding to estramustine phosphate was similar (20 weeks) to that for vincristine (22 weeks) and greater than that for the combination (13 weeks). The probability of survival did not differ significantly for patients randomized to each of the 3 regimens. The addition of vincristine to estramustine phosphate did not enhance the response rate achieved by estramustine phosphate alone and vincristine alone produced the lowest response rate. Estramustine phosphate continues to be the most active agent in previously irradiated patients with hormonally refractory metastatic cancer of the prostate.

Drug Therapy, Combination↗

A comparison of hydroxyurea, methyl-chloroethyl-cyclohexy-nitrosourea and cyclophosphamide in patients with advanced carcinoma of the prostate.

This is the fifth completed randomized clinical trial of the National Prostatic Cancer Project. There were 125 patients with histologically confirmed relapsing clinical stage D prostatic cancer randomized to receive hydroxyurea, methyl-chloroethyl-cyclohexy-nitrosourea or cyclophosphamide. All patients had received and failed previous hormonal therapy. Patients whose disease progressed after 12 weeks on the initial therapy were crossed over or randomized to receive an alternate drug. There were 98 patients available for comparison of treatments. Objective responses included patients with complete or partial regression as well as stable disease. The response rates were 35 per cent for cyclophosphamide, 30 per cent for methyl-chloroethyl-cyclohexy-nitrosourea and 15 per cent for hydroxyurea. Subjective response parameters included improvement in performance status and relief of pain. Pain was improved in a fifth of the patients on each treatment area. Methyl-chloroethyl-cyclohexy-nitrosourea and hydroxyurea showed activity in advanced prostatic cancer patients but at the expense of excessive toxicity. Cyclophosphamide continues to be the most active single agent in this type of patient, particularly with regard to duration of response and survival. There was a statistically demonstrable advantage for cyclophosphamide over hydroxyurea and a marginal advantage over methyl-chloroethyl-cyclohexy-nitrosourea in survival experience.

Acid Phosphatase↗

Bladder-surface glycosaminoglycans: an efficient mechanism of environmental adaptation.

The transitional epithelium of the urinary bladder secretes and binds to its surface a glycosaminoglycan than inhibits the adherence of bacteria. Synthetic sulfonated glycosaminoglycans instilled intraluminally into bladders whose natural mucin layer has been removed are as effective as the natural mucin in preventing bacterial adherence. It also appears that adherence of calcium and protein is reduced in the presence of both the natural mucin layer and the synthetic sulfonated glycosaminoglycan sodium pentosanpolysulfate, suggesting that the antiadherence activity of both natural and synthetic surface glycosaminoglycans in the bladder extends to the molecular and ionic levels.

Adsorption↗

Thrombocytopenia during diethylstilbestrol diphosphate (stilphostrol) infusion for carcinoma of the prostate.

Transient thrombocytopenia was noted to occur in ten of 13 patients with advanced carcinoma of the prostate undergoing intravenous diethylstilbestrol diphosphate therapy. This was not associated with abnormalities of the initial platelet count or other parameters of the hemogram. There was no evidence of disseminated intravascular coagulation in these patients. No serious bleeding episodes occurred secondary to the thrombocytopenia. Following diethylstilbestrol diphosphate infusion, platelet counts generally returned to pretreatment levels. While the mechanism of action of the thrombocytopenia is unclear, we hypothesize a transient bone marrow toxicity as the cause of this phenomenon.

Adenocarcinoma↗

Percutaneous nephrostomy: experience in 107 kidneys.

We were successful using percutaneous nephrostomy to relieve upper urinary obstruction in 98 of 107 kidneys. In two thirds of our patients obstruction was due to neoplasm, with prostatic cancer the leading cause. Percutaneous nephrostomy proved to be ideally suited for drainage of pyonephrosis and in azotemic patients. Its use can obviate surgical nephrostomy and prolonged ureteral catheter drainage. We also are encouraged by our early experience with extensions of percutaneous nephrostomy, including percutaneous ureteral stenting, renal stone dissolution, and percutaneous pyelolithotomy.

Angiography↗

In vitro bacterial adherence to vaginal cells of normal and cystitis-prone women.

Using an in vitro assay system to quantitate the adherence of Escherichia coli to vaginal cells we found no statistically significant difference in mean bacterial adherence per cell in either infection-prone or normal women at either pH 6.4 or 4.0, which is that of the normal vaginal introitus. In addition, we found that the assay method used by previous investigators contained large sources of error, making it difficult to draw conclusions based upon the data obtained with this method.

Adult↗

Direct vision internal urethrotomy in the management of urethral strictures.

Direct vision internal urethrotomy is a safe, effective means to treat urethral strictures and vesical neck contractures. Its success rate approaches 90 per cent with 6 months of followup, although a longer interval may be necessary for a more accurate record. It often can be performed in an outpatient setting, under topical anesthesia and with only 1 day of catheter drainage, which provides considerable savings in hospital costs.

Costs and Cost Analysis↗

Antibacterial activity of bladder surface mucin duplicated in the rabbit bladder by exogenous glycosaminoglycan (sodium pentosanpolysulfate).

Previous data from our laboratory suggest that the transitional epithelium of the urinary bladder secretes and binds to its surface a glycosaminoglycan. The presence of this substance at the bladder surface markedly reduces the ability of microorganisms to adhere to the mucosa. Furthermore, this glycosaminoglycan can be removed (with acid) and replaced by intravesical instillation of a synthetic sulfonated glycosaminoglycan (heparin), whose presence is as effective as that of the natural glycosaminoglycan in reducing adherence. We conducted the current study with a different sulfonated glycosaminoglycan to determine whether the antiadherence activity is generalized to heparin congeners and whether the antiadherence effect of heparin is independent of its known anticoagulant activity. In this study we examined the sulfonated glycosaminoglycan, sodium pentosanpolysulfate, which lacks significant anticoagulant activity, and found it to have a mechanism of antiadherence analogous to that of heparin and almost equally as active on a weight basis.

Animals↗

Bone pain in metastatic cancer of prostate.

The characteristics of bone pain in metastatic cancer of the prostate were studied in 23 patients. The pain may be continuous or intermittent, show diurnal variations, and be migratory. The effects of activity, rest, and alcohol vary in different individuals. Relief of bone pain by analgesic medications is unsatisfactory. Aspirin-containing compounds are often more effective than narcotics for pain relief. The effects of external beam irradiation for palliation of pain are unpredictable.

Adenocarcinoma↗

Diagnostic fine needle aspiration of soft tissue metastases from cancer of the prostate.

Pathologic confirmation of soft tissue metastases is necessary for staging and followup of patients with cancer of the prostate. Fine needle aspiration with cytologic evaluation is recommended over other biopsy procedures because it is safe, accurate and applicable to deep and superficial lesions. Small metastases, such as lymph nodes or skin nodules, remain in situ as useful markers to follow the course of the disease and response to treatment.

Abdominal Neoplasms↗