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P Felding

Publications and source records attributed to P Felding.

26 records · Page 2Linked to original sources
PubMed1983

Factors responsible for the decreased plasma concentration of prealbumin during acute inflammation and fasting in the rat.

The concentration of prealbumin in plasma and the elimination from plasma and whole body of intravenously injected 131I-labelled rat prealbumin were followed in normal rats and rats subjected to fasting or acute inflammation. During fasting and inflammation the concentration of prealbumin decreased to about 50% of the initial value. It was concluded from the radioactive tracer experiments that decreased synthesis was responsible for the decreased intravascular prealbumin mass in the fasting rats. In these rats the plasma volume also decreased. In the rats subjected to inflammation, both a decreased intravascular fraction and a decreased synthetic rate of prealbumin seemed to contribute to the decreased intravascular mass of prealbumin. The total catabolic rate was decreased in these conditions.

Acute Disease↗
PubMed1982

Cellular origin of prealbumin in the rat.

The synthetic rate of prealbumin and albumin in primary monolayer cultures of rat hepatocytes was measured by immunochemical methods. The isolated hepatocytes synthesized these proteins in the same ratio as that previously found for the whole body synthesis in vivo. It is concluded that the hepatocytes synthesize the main part of prealbumin in the rat.

Animals↗
PubMed1981

The stability of blood, plasma and serum constituents during simulated transport.

The aim of the study was to simulate physical conditions occurring during mail transport and to study how these conditions influence the stability of material for clinical chemistry analysis. Periods of transport at constant temperatures did not result in big changes. We found that all serum and plasma constituents tested should be considered stable for 4 days at -20 degrees C. Except for the coagulation factors studied all other serum and plasma constituents were stable also at 4 degrees C and 20 degrees C. Blood cells were studied only at 4 degrees C at which temperature they were stable for 4 days except for thrombocytes. The condition that caused the largest effect was changing of temperature. Temperature gradient from ambient to 50 degrees C influenced the concentrations of all cells in blood, of coagulation factors in plasma and of enzymes in serum. The constituents were remarkably stable during shaking. The results agreed with those of a field study on the effect of mail transport by Berg et al. [3].

Blood↗
PubMed1980

Plasma prealbumin concentration in alpha 1-antitrypsin deficiency (PiZ).

The concentrations of 7 plasma proteins including prealbumin, retinol-binding protein, and alpha 1-antitrypsin were measured by electroimmunoassay in plasma from 19 persons with alpha 1-antitrypsin deficiency PiZ, 20 persons with phenotype PiMZ, and 26 healthy men with normal alpha 1-antitrypsin content. The prealbumin concentrations in the PiZ individuals were slightly lower than in the other groups. Only one individual in the PiZ group showed very low levels of prealbumin and retinol-bonding protein. Thus contrary to what has been proposed earlier our results show that severe prealbumin deficiency is not a common finding in alpha 1-antitrypsin deficiency PiZ.

Adolescent↗
PubMed1980

Effects of posture on concentrations of blood constituents in healthy adults: practical application of blood specimen collection procedures recommended by the Scandinavian Committee on Reference Values.

Different procedures for the collection of blood for the determination of reference values in healthy adults have been subjected to practical testing. The Scandinavian Committee on Reference Values suggested that subjects lying in bed after an overnight sleep and ambulatory individuals, after 15 min of sitting in a chair, were two suitable and different reference populations. In forty subjects we found an increase from lying to sitting position of about 6.5% in the serum concentrations of proteins, enzymes and lipids. The corresponding increases for S-calcium and B-haemoglobin were approximately 3% whereas S-thyroxine, unexpectedly, changed by 11%. There were no significant changes of potassium and sodium values. For some constituents the changes were age and sex-dependent being greater in a group of elderly women as compared to a group of younger men. After 1 h of recumbency the concentrations of the constituents generally returned to those in the initial, lying position.

Adult↗
PubMed1980

Effects of posture on concentrations of serum proteins in healthy adults. Dependence on the molecular size of proteins.

The effect of posture on changes in protein composition of serum and its dependence on molecular size has been investigated in forty individuals classified by age and sex. Blood specimens were drawn (A) at 0700 hours with persons still resting in bed after an overnight sleep; (B) at 0815 hours, in sitting position after 1 h of moderate exercise and again (C) at 0915 hours, lying in bed after 1 h of recumbency. Concentrations of alpha 1-antitrypsin, albumin and alpha 2-macroglobulin in serum were determined with high analytical precision. The mean fractional increases of concentrations from lying (A) to sitting (B) were 0.069 for alpha 1-antitrypsin and 0.063 for albumin, but lower, 0.040, for alpha 2-macroglobulin. Thus these increases, being related to molecular size, were not simply caused by posture induced changes of plasma volume. Considering the results of each individual we found a constant difference between the increase of alpha 1-antitrypsin and alpha 2-macroglobulin of about 0.030 for the whole range of increases (i.e. for alpha 1-antitrypsin 0-0.15). In contrast, the effects of recumbency were independent of molecular size. The mean, fractional decreases in concentration induced by changing of position from sitting (B) to lying (C) were approximately 0.065 for all three proteins.

Adult↗