Biomedical subjects

R A Olshen

Publications and source records attributed to R A Olshen.

22 records · Page 2Linked to original sources

PubMed1983

Intraperitoneal cis-diamminedichloroplatinum with systemic thiosulfate protection.

The toxicity and pharmacokinetics of cis-diamminedichloroplatinum (cisplatin) (90 mg/sq m) administered as a single 4-hr peritoneal dialysis, with or without concurrent i.v. infusion of sodium thiosulfate, 0.43 or 2.13 g/sq m/hr for 12 hr, were studied on 20 courses of treatment. When given without thiosulfate, the toxicity of cisplatin was systemic rather than local, and the peritoneal cavity/plasma ratio of the area under the curve was 12. Addition of i.v. thiosulfate significantly reduced the nephrotoxicity. The concentration of cisplatin in the peritoneal cavity was sufficiently greater than that in the plasma to prevent thiosulfate, which equilibrated into the cavity, from interfering with the antitumor activity of cisplatin in the peritoneum. This study demonstrates a pharmacokinetic advantage of i.p. chemotherapy with cisplatin.

Adult↗

PubMed1982

Intraperitoneal cisplatin with systemic thiosulfate protection.

Seventeen patients with intraperitoneal tumors were treated by 4-hour intraperitoneal dialysis with cisplatin alone, or in combination with an intravenous neutralizing agent, sodium thiosulfate. Cisplatin alone, 90 mg/m2 body surface area intraperitoneally, produced nephrotoxicity. When intraperitoneal cisplatin therapy was combined with intravenous thiosulfate treatment, the dose of cisplatin could be escalated to 270 mg/m2 body surface area without causing an increase in serum creatinine levels or undue myelosuppression. Even at doses up to 270 mg/m2, no local toxicity occurred. The peak peritoneal concentration of free reactive cisplatin averaged 21-fold higher than the plasma level, and the area under the peritoneal cisplatin elimination curve averaged 12-fold more than the area under the plasma curve. Neither of these ratios varied significantly with cisplatin dose. Regression of intraperitoneal tumor masses was observed in patients with far-advanced ovarian carcinoma, mesothelioma, and malignant carcinoid.

Adult↗

PubMed1979

Effect of probenecid on cerebrospinal fluid methotrexate kinetics.

The effect of probenecid (PBC) on methotrexate (MTX) kinetics in the cerebrospinal fluid (CSF) and serum was studied in 4 patients on high-dose MTX with leucovorin rescue to determine whether addition of PBC could prolong effective CSF MTX levels. Each patient received 2 courses of MTX, 1 with and 1 without PBC. PBC caused a 2.8 to 4.2-fold increase in CSF MTX concentrations but failed to prolong the CSF half-life (1 1/2). PBC prolonged the initial MTX elimination t 1/2 in the blood from 2.7 to 4.1 hr, but had little effect on subsequent t 1/2s. No effect of MTX on PBC clearance was detected. Our data suggest that in man PBC in concentrations that were high enough to inhibit the renal clearance of MTX failed to alter the clearance of MTX from the CSF when both drugs were administered systemically.

Adult↗

PubMedDate not supplied

Statistical analysis of gait patterns of persons with cerebral palsy.

Patients at Boston's Children's Hospital diagnosed as having cerebral palsy were filmed walking. These films were digitized and translated into measurements associated with leg motion. In this paper we use the gait measurements of 128 such patients to illustrate the the kth nearest neighbour clustering procedure results in a gait typology for patients with cerebral palsy. The procedure identifies four subpopulations from the sample data; the membership of a patient within this typology is mostly determined by the patient's motor control. The developed typology differs from the present diagnostic system which classifies a cerebral palsy patient as either quadriplegic, diaplegic or hemiplegic.

Biomechanical Phenomena↗