Red cell pyrimidine 5' nucleotidase deficiency: determination of nucleotidase activity and nucleotide content using HPLC.

The hereditary deficiency of erythrocyte pyrimidine 5' nucleotidase has been investigated using an HPLC anion-exchange procedure designed to measure both red cell nucleotide content and enzymic activity. Red cell nucleotide profiles were determined using a low pH phosphate buffer salt-gradient system in 20 min, whereas a low pH buffer alone permitted the determination of enzymic activity with each of six different nucleotide substrates in less than 4 min. Both the red cell nucleotide profiles and the enzymic activity of haemolysates from two affected brothers and their children agreed well with previously published values.

The effect of dietary amino acids on the gastrointestinal absorption of melphalan and chlorambucil.

Previous studies have demonstrated that the bioavailability of melphalan and chlorambucil may be reduced under non-fasting conditions, and that the gastrointestinal and cellular absorption of melphalan is an active process, while that of chlorambucil is passive. In view of these findings, the effect of dietary amino acids on the gastrointestinal absorption of these two drugs was investigated using the in situ rat intestine model. The segment lengths used in the study were (mean +/- SD) 47.

Protein losses and tobramycin absorption in peritonitis treated by hourly peritoneal dialysis.

The effects of peritonitis on dialysate protein losses of IgG, IgA, IgM, transferrin, and complement were investigated. Thirteen patients who developed peritonitis while undergoing peritoneal dialysis were compared with seven noninfected dialysis patients. Dialysate protein losses increased during peritonitis, but IgG, IgA, IgM, transferrin, and complement losses did not.

Effect of intraperitoneal insulin on solute kinetics in CAPD: insulin kinetics in CAPD.

The authors evaluated the transport kinetics of insulin and inulin administered intraperitoneally to six diabetic patients undergoing continuous ambulatory peritoneal dialysis. The mass transfer coefficients (MTC) calculated from dialysate to blood for 1.5% and 4.

Renal function in the elimination of oral melphalan in patients with multiple myeloma.

Pharmacokinetic studies in 11 patients with multiple myeloma were undertaken on the first and last days of one course of chemotherapy. The drug was administered PO in single doses of 6-14 mg daily. Melphalan concentrations were determined by high-performance liquid chromatography.

Can food affect the bioavailability of chlorambucil in patients with haematological malignancies?

Pharmacokinetic studies in ten patients with haematological disorders were undertaken on the first and second days of one course of chemotherapy. Patients received chlorambucil under fasting and non-fasting conditions. Plasma concentrations of chlorambucil were determined by a reversed-phase high-performance liquid chromatography assay.

Studies on the mechanism of gastrointestinal absorption of melphalan and chlorambucil.

The uptake of melphalan into tumour cells has been shown previously to involve active transport, while that of chlorambucil is by passive diffusion. In view of these findings, the mechanism of their gastrointestinal absorption was investigated using the in situ rat intestinal model. Segment lengths in all cases were (mean +/- SD) 47.

Echovirus meningomyeloencephalitis with administration of intrathecal immunoglobulin.

Echovirus meningomyeloencephalitis was treated with cerebral intraventricular immunoglobulin. This case includes a complete examination of the central nervous system (CNS) supported by viral culture studies, immunoperoxidase staining and electron microscopy. Neuronal loss was most severe in the cerebellum and spinal cord.

A double blind trial of dipyridamole in CAPD.

Since we had previously shown that dipyridamole augmented inulin and glucose clearance during intermittent peritoneal dialysis we sought to extend our study to the patient undergoing continuous ambulatory peritoneal dialysis. We carried out a double blind study in which patients received either 75 mg of active drug or placebo for a 2-week period. At the end of this period the mass transfer coefficients, between plasma and dialysate, were measured for selected solutes.

Dialysate flow rate and peritoneal clearance.

We evaluated the influence of dialysate flow rates upon peritoneal clearance of urea, creatine, protein losses into dialysate, glucose disappearance from dialysate, sodium removal from the patient during dialysis, and ultrafiltration rate in 64 patients undergoing intermittent peritoneal dialysis. We evaluated three dialysate flow rates: 2 L/h, 3 L/h, and 4 L/h. All dialysate contained 1.

Augmentation of peritoneal clearance by dipyridamole.

We performed a double blind crossover trial in which dipyridamole was administered to ten patients undergoing intermittent peritoneal dialysis at 2 liters/hour (10 min infusion, 30 min intraperitoneal dwell of dialysate and 20 min drainage of dialysate). After the patients received the drug for 3 days at a dose of 75 mg three times daily, peritoneal inulin clearance increased by 1.2 ml/min (P less than 0.

The Tenckhoff catheter for peritoneal dialysis--an appraisal.

We prospectively evaluated early (within 40 days) catheter complications in all patients receiving a dialysis catheter between 1/8/80 and 1/8/81. 50% of patients achieved a functioning catheter at the first insertion and 24% required replacement of the catheter because of poor dialysate flow. Leaking from the catheter exit site occurred in 20%, infection at the exit site in 9% and peritonitis in 19% of patients.

Stereospecific lactate absorption during peritoneal dialysis.

Patients undergoing peritoneal dialysis were studied to determine if peritoneal absorption was selective. Dialysis was performed using dialysate exchange schedules similar to those for intermittent peritoneal dialysis and continuous ambulatory peritoneal dialysis. The clearance rate from the peritoneal cavity during hourly dialysate exchanges was 6.

Polypeptides specified by bacteriophage T1.

The proteins synthesized during the replication of phage TI in u.v.-irradiated Escherichia coli strain B have been examined by polyacrylamide gel electrophoresis of polypeptides pulse-labelled with 14C-amino acids.