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Biomedical subjects

K J Berg

Publications and source records attributed to K J Berg.

At least 127 records · Page 7Linked to original sources
PubMed1979

Transport of uremic toxins through conventional hemodialysis membranes.

Human mononuclear phagocytes cultured in vitro were tested after preincubation with uremic plasma dialyzed in vitro and the effects of pre and post hemodialysis plasma were compared with the effect of dialyzates equilibrated with uremic plasma in vivo. Factors in uremic blood plasma inhibiting phagocytosis of Candida albicans could not be removed by means of conventional hemodialysis with cuprophan (CPN) or polyacrylonitrile (PAN) membranes. Hemofiltrates of uremic blood plasma produced by PAN membranes caused a significant inhibition of phagocytes in our test system while CPN hemofiltrates did not.

Acrylonitrile↗
PubMed1979

Removal of uraemic toxins by haemofiltration with different membranes. The benefit of regenerating haemofiltrate using a newly developed system.

Based on earlier results which indicate that certain uraemic toxins (verified by an in vitro assay system) are larger than 10,000 daltons - a new system for treatment of endstage renal failure, SElective DUal Filtration ARtificial Kidney (SEDUFARK) has been developed. This system consists of a multimembrane filter/dialyser unit making removal of small molecules (mol wt less than 200) and substances in the mol wt range 10,000 - 40,000 possible without exchange of body fluids. Evaluation of pre and post treatment uraemic plasma with the bio assay showed that SEDUFARK was superior to conventional haemofiltration (CHF) with polyacrylonitrile (PAN) or Gambro Lundia Major High Flux 1.36 m2 (CPN) membranes as filters.

Blood↗
PubMed1978

Mathematical and clinical investigation of the RP6-rhodial 75 system. Evaluation of high and low middle molecular clearance dialysis.

The clearance for "middle molecules" measured in vitro was considerably higher for a polyacrylonitrile than for a cuprophan membrane, even when the former had been used for patients three times. Using a two pool mathematical model, an adequate correlation was found between the calculated values and those measured during RP6-Rhodial 75 dialysis (RP6). The treatment time needed for dialysis of "middle molecules" with the Gambro 13.5mu in single pass (Gambro S. P.) was four times longer than with RP6. In a long-term clinical study, when RP6 and Gambro S. P. dialysis were compared, no difference in the clinical condition of the patients was found. Clinical condition was not affected by the urea or "middle molecule" levels. The ultrafiltration tolerance was improved during hemodialysis with systems resulting in a low urea clearance.

Acrylonitrile↗
PubMed1977

Acute acetylsalicylic acid poisoning: treatment with forced alkaline diuresis and diuretics.

101 patients were treated for acute acetylsalicylic acid (ASA) poisoning in the Nephrological Unit Trondheim between 1971-1975. On admission 33 of them had a serum salicylic acid (SA) concentration greater than 400 microgram/ml (mean 588 +/- 40 microgram/ml). This group was compared with a group of 11 children less than 5 years old with ASA poisoning and a mean serum SA on admission of 550 +/- 34 microgram/ml. Blood pH on admission was normal or elevated in all patients more than 12 years old (mean 7.43 +/- 0.01), whereas 7 of the 11 children suffered from metabolic acidosis. The results of forced alkaline diuresis produced by loop diuretics (bumetanide, furosemide) in ASA poisoned patients older than 12 years are reported. The mean T 1/2 of SA was 9.6 h in the treated group as compared to 18-22 h in untreated patients. There was no apparent difference between the diuretic effect of bumetanide and furosemide.

Acid-Base Equilibrium↗
PubMed1977

Acute effects of acetylsalicylic acid in patients with chronic renal insufficiency.

The effect of acetylsalicylic acid (ASA) in patients with renal insufficiency has been examined. In one investigation (A), in patients with a mean GFR of 23.0 ml/min the acute effects of ASA 750 mg i.v. (lysine-ASA 7.5 ml) and 0.9% NaCl 7.5 ml on renal water and solute output and on the clearance of inulin, creatinine and PAH were compared. In another (B) the effects of simultaneous administration of ASA 750 mg or 0.9% NaCl 7.5 ml i.v. with an infusion of furosemide 250 mg were investigated in six patients (mean GFR 12.9 ml/min) in a cross-over study. In study A there was a significant fall in urinary sodium excretion within the first 15 min after ASA administration, with a maximal decrease to 21% of the control period. Urine flow fell to 35%, osmolal clearance to 41%, inulin clearance to 54% and PAH clearance reabsorption of sodium increased. The effect of ASA lasted for 2-6 h. The mean salicylic acid concentration during the first two hours after ASA administration was 60.0 mug/ml, and the mean protein bound salicylic acid (SA) was 70.4%. There was no effect of placebo (0.9% NaCl 7.5 ml) on renal function. Pretreatment with ALA 750 mg i.v. attenuated the diuretic effect of furosemide 250 mg, and reduced creatinine clearance significantly within 0-2 h after drug administration.

Aged↗
PubMed1977

Acute effects of acetylsalicylic acid on renal function in normal man.

The acute effects of therapeutic doses of acetylsalicylic acid (ASA) on renal water and solute output, and the possible interaction of ASA with the diuretic effects of furosemide, have been studied in a double blind double cross over study in healthy human subjects. There was a significant decrease in 24 h sodium excretion and Na/K ratio in urine in the ASA-treated subjects. The effect of ASA on urinary sodium excretion was most prominent during day time (8 a.m.-10 p.m.) and on days with low sodium intake, as confirmed by control sodium excretion and plasma renin activity. A decrease in urine volume and an increase in tubular reabsorption of free water were caused by ASA, the antidiuretic effect being most marked at night (10 p.m.-8 a.m.). No action of ASA on the effect of furosemide on urinary sodium excretion was found. Creatinine clearance remained unaltered by ASA treatment, and ASA did not interfere with the increase in urinary creatinine excretion after furosemide treatment.

Aspirin↗
PubMed1977

Effects of different doses of acetylsalicylic acid on renal oxygen consumption.

The aim of the present study was to examine the acute effect of acetylsalicylic acid (ASA) on renal oxygen consumption (Qo2) and renal sodium excretion (UNaV) in anaesthetized dogs. With plasma salicylic acid (SA) concentrations ranging from 200-400 microgram/ml, Qo2 increased 36% (P less than 0.05) in spite of a 16% decrease in renal blood flow. At plasma SA concentrations of 80-200 microgram/ml Qo2 was significantly increased 45 min after the onset of ASA infusion. UNaV decreased from 97.7 to 21. 5 mumol/min (P less than 0.05). Glomerular filtration rate and absolute tubular reabsorption of sodium (RNa) was unchanged. The ratio RNa/Qo2 decreased from 31.0 to 21.3 (P less than 0.05). Renal lactate uptake increased. The results are most consistent with an uncoupling affect of ASA on oxidative phosphorylation in the kidney.

Animals↗
PubMed1977

Inhibition of furosemide-induced natriuresis by acetylsalicylic acid in dogs.

The effect of intravenously administered acetylsalicylic acid (ASA) has been investigated in two sets of experiments in conscious dogs. In the first part of the study ASA 70-90 mg/kg was infused for 40 min. Urine flow, free water clearance, renal blood flow and urinary excretion of sodium did not change significantly as compared to placebo treated animals. This is in contrast to the effects of comparable ASA doses in the pentobarbital anaesthetized dog. In the second part of the study the effects of pre-treatment with the same ASA doses of 5 ml 0.6% NaCl (placebo) on some renal effects of furosemide 1 mg/kg (intravenously) were investigated. In the placebo group acute furosemide treatment increased CIN in five out of six dogs and CPAH in all six dogs, these increases being most prominent the first 10 min after drug administration. After pre-treatment with ASA the initial increases in CIN and CPAH were almost abolished. CIN was reduced by 23.8% and CPAH by 30.6% during the first six clearance periods (0-6- min) after diuretic treatment in the ASA group as compared to the placebo group. Although urinary sodium excretion also increased in ASA pre-treated dogs, the effect of furosemide was greater in all dogs in the placebo group (P less than 0.05), and the effect of furosemide on fractional tubular reabsorption of sodium was significantly attenuated after pre-treatment with ASA.

Animals↗
PubMed1976

Diuretic action of bumetanide in advanced chronic renal insufficiency.

The effect of bumetanide, a new potent diuretic, was studied in twelve patients with severe chronic renal failure (GFR 2.7 - 10.7 ml/min). Bumetanide 8 mg i.v. caused increased excretion of water and sodium in all patients. In some patients sodium excretion was greater than 50% of filtered load indicating an effect on proximal tubules. Bumetanide 2 mg i.v. was significantly less effective than 8 mg and a greater diuretic effect was produced by bumetanide 16 mg. In a comparative study bumetanide 8 mg was less potent than furosemide 250 mg, a finding in contrast to the potency rate ratio of 1/40 in other conditions. Side effects consisted of mild to moderate muscle pain and stiffness, especially localized in the neck, shoulders and calves. These side effects occurred only in patients with a GFR less than 5.3 ml/min. They were noted in all patients receiving 16 mg and in 3 out of 12 patients who took bumetanide 8 mg. There was no relationship between the occurrence of side effects and plasma bumetanide levels, electrolyte levels or the renal excretion of bumetanide and electrolytes.

Adult↗
PubMed1976

Effects of different doses of acetylsalicylic acid on renal function in the dog.

This study was carried out in order to examine the effect of increasing doses of intravenously administered lysine-acetylsalicylic acid (ASA) on renal function in dogs. The first purpose was to examine the acute effects on renal water and solute output. The second purpose was to correlate the para-aminohippuric (PAH) clearance measurements with measurement of renal PAH extraction and renal blood flow (RBF). After 7 mg/kg ASA (20-80 microgram SA/ml plasma) a decrease in sodium excretion was observed in all dogs. With increasing ASA doses, the urine sodium excretion declined to 23% of the control period excretion. Tubular reabsorption of free water increased 10%. A significant and dose-related decrease in PAH clearance was observed in all dogs, from 108.7 ml/kg ASA to 58.8 ml/min after 200 mg/kg ASA. The creatine clearance was unchanged. PAH extraction fell in all dogs, RBF (measured by flowmeter decreased 21% at the highest plasma SA levels, as compared with 46% decrease in PAH clearance. ASA seems to inhibit tubular transport of PAH. Inhibition of prostaglandin synthesis by ASA offers one explanation of the effects of RBF and sodium excretion.

Animals↗
PubMed1976

Effects of different doses of chlorpromazine on renal function in the dog.

This study was carried out to examine the effects of low 'alpha-blocking' and higher 'membrane-stabilizing' doses of chlorpromazine (CPZ) on renal function. CPZ was given at slow infusion rate either intravenously or into the left renal artery at three levels (0.5-1.0, 3-8, and 10-15 mg/kg) to 10 anesthetized dogs. An increase in plasma hemoglobin sometimes occurred within few minutes after infusion of more than 10 mg/kg CPZ, probably due to a hemolytic effect of such high doses. Systemic infusion of 0.5-1 mg/kg CPZ caused an increase in urine volume, sodium excretion, and renal plasma flow, and a decrease in filtration fraction and free water clearance was demonstrated in all dogs. At higher CPZ doses renal plasma flow increased further, whereas urine volume and electrolyte excretion were of the same order at all dose levels. A 21% decrease in tubular maximum para-aminohippurate transport (Tm(PAH)) was observed at the highest CPZ doses. After unilateral renal intra-arterial CPZ infusion the percentage change in urine volume, urinary sodium excretion, and Tm(PAH) were of the same order on the infused side as on the contralateral side. Even though the results at all dose levels can be explained by an 'alpha-blocking' effect of CPZ, possible membrane-stabilizine effects of CPZ cannot be excluded.

Animals↗
PubMed1975

A mathematical single-pool model for short time haemodialysis.

The objective was to reduce treatment time while the average concentration of all molecular sizes was maintained equal to that in a standard treatment. A nomogram based on the one-pool patient-dialyser system has been devised. The patient variables are presented in dimensionless forms, thus making on diagram suffice for all patients and all molecular sizes. Seven patients were first observed during a standard programme and later during an individually calculated short-time programme. The clinical parameters indicated equal treatment. The method was practical enough for clinical use.

Aged↗