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Biomedical subjects

K Adam

Publications and source records attributed to K Adam.

At least 73 records · Page 4Linked to original sources
PubMed1982

A comparison of the effects of chlormezanone and nitrazepam on sleep.

1 Twelve volunteers, of mean age 60 years, took part in a double-blind, balanced cross-over study, to compare effects of chlormezanone 400 mg and nitrazepam 5 mg on electrophysiologically-recorded and subjectively-rated sleep. 2 In the first week of administration nitrazepam caused a significant shortening of the time to fall asleep, but following withdrawal subjects took longer to fall asleep than during the baseline period. 3 Both chlormezanone and nitrazepam initially caused increase of sleep duration and less interruption of sleep by wakefulness. By the third week, for chlormezanone this effect was no longer significant, and for nitrazepam there was a significant decline in the effect. There was no statistically significant difference between the two drugs for these measures. 4 The drugs differed little in their effects on the amount of the various sleep stages, except that nitrazepam significantly reduced the duration of slow wave sleep, whereas chlormezanone had no significant effect on slow wave sleep. Both drugs reduced the amount of REM sleep in the first 6 h of sleep but only nitrazepam reduced the percentage of the time spent in REM sleep of the whole night. 5 Subjects' own ratings of sleep quality showed that both of the drugs improved sleep, but following withdrawal it was only after nitrazepam that there was impairment of the quality of sleep. Neither drug affected subjective alertness in the morning.

Adult↗
PubMed1982

Sleep is changed by blood sampling through an indwelling venous catheter.

Seven volunteers, four men and three women aged 53-63 years, each had his or her sleep recorded electrophysiologically on twelve baseline nights and on two nights during which a catheter had been inserted into a forearm vein. On the catheter nights, total sleep time and sleep efficiency were both reduced significantly, there was significantly more wakefulness after the first onset of sleep, and there was less rapid eye movement (REM sleep. The effects on REM sleep were attributable almost entirely to a significant reduction in the amount of REM sleep in the second half of each catheter night. Possible explanations of the effect of REM sleep are discussed.

Adrenal Cortex Hormones↗
PubMed1981

[Isobutylidene urea as NPN source for ruminants. 2. Digestion of 15N-labeled isobutylidene urea in lactating dairy cows].

Two cows with rumen cannulae and duodenal re-entrance cannulae received in the first experiment (Ia and IIa) a conventional diet on the basis of a mixture of maize silage, hay and concentrated feed and after a three-week adaptation to isobutylidene diurea (IBDU)--276 g per animal and day--138 g IBDU with 3.865 mg 15N-excess as a single supplementation to their first meal. In the second experiment (IIa and IIb) after a 6-week break the same cows served a repeated experiment without IBDU adaptation. Irrespective of the adaptation, a re-increase of the 15N-labelling in the TCA-soluble N in the rumen could be proved between the 6th and the 8th hour after the intake of the isotopes, which resulted from the backflow of 15N to the rumen. In the duodenal digesta the maximum labelling of the TCA--soluble N-fraction appeared 12 hours after the intake of the isotopes. At that moment a labelling plateau began in the protein fraction, which lasted to the 36th hour. On an average of all 4 cows approximately 30% of the 15N taken in the TCA-precipitable fraction and 55 and 60% in the TCA-soluble fraction had passed the duodenum up to the 72nd hour after the beginning of the experiment. Up to the 72nd hour after the beginning of the experiment, approximately 15% were excreted in urine, approximately 16% in feces and approximately 7% in the milk. This shows that roughly one half of the 90% 15N-amount measured at its passage in the re-entrance cannula (related to the intake) was metabolised in the rumen at least twice, resp. after the first passage through the duodenum it originated from the intermediary metabolism (e.g. as amino acids and their incorporation as digestion secretions). Negative correlations could be ascertained between the pH-value of the rumen fluid and the 15N incorporation in the rumen proteins as well as 15N-excretion through the TCA-soluble and -precipitable quota of feces. An adaptation to IBDU is obviously not necessary.

Animal Feed↗
PubMed1981

[Absorption of 14C-leucine and 15N-leucine in rats after feeding a fish meal diet in comparison with a gelatin diet].

Albino rats received after nine days of adaptation to a fish meal diet in comparison with a gelatin diet 14C-U-Leucine and 15N-L-leucine via a pellet made from the specific diet after food deprivation for 15 h. Thereafter, the experimental animals consumed the non-labelled experimental diet ad libitum. Five times after the pellet intake, 30 min, and 1, 2, 4 and 6 h after injection of the labelled food, four experimental rats were sacrificed. The contents of the digestive tract and tissue samples were examined for 14C and 15N. We detected to following percentages of 14C-intake or the intake of 15N-excess (15N') in the TCA-soluble fraction of the gastric contents: [Formula: see text] We found in the TCA-soluble fraction of digesta of small intestine the following percentage of intake: [Formula see text] Where these values regarded as non-absorbed leucine, the 14C values obtained up to four hour period of experiment would be too high. Presumably, they are in the case of both diets simulated by other 14C-metabolites which originate from the leucine catabolism and reach the intestinal lumen. Amino acids labelled with 15N should be preferred in studies on the absorption of amino acids because, in case of catabolism, the 15N-aminogroup is excreted mainly in the form of urea via urine.

Animal Feed↗
PubMed1981

Lack of effect on mental efficiency of extra vitamin C.

Twenty men (mean age 21 yr) took part in a double-blind cross-over trial to compare psychomotor performance when plasma vitamin C levels were high (16.28 +/- 3.75 mg/l) owing to supplementation, with times when levels were low (6.15 +/- 3.88 mg/l). Subjects were tested at 0730, 1130, and 1900 h by an hour-long auditory vigilance test to assess alertness, a digit-symbol substitution task to test short-term memory, and a memory-for-digits test to measure immediate memory. No significant differences were found on these measures of performance, nor was there any change in their subjectively rated sheep quality, alertness, concentration, or mood.

Adolescent↗