Biomedical subjects

D Elmqvist

Publications and source records attributed to D Elmqvist.

At least 55 records · Page 3Linked to original sources

PubMed1975

Effects of a new butyrophenone derivate (Buronil) on nocturnal sleep in normal man.

Nocturnal sleep was studied in eight young normal volunteers (3 female and 5 male students) with polygraphic technique during 2 periods of 10 night each. After 2 adaptation and 2 baseline nights with placebo, they were given methylperone (Buronil) 10 or 50 mg per night during three nights and then again placebo for three withdrawal nights. The study was made double blind. The scoring of the records was done according to the manual by Rechtschaffen and Kales (1968). No changes of sleep stages were seen during the drug periods. The lower dose gave an increase of sleep latency but a decrease of number of awakenings during the night. An increase of REM-periods was shown after 50 mg and also a decrease of REM-latency and REM-density. The only significant change during withdrawal periods was a decrease of REM-sleep after methylperone 50 mg, so there was no "barbiturate type" of withdrawal. The change was also different from that of chloropromazine, which has no clear rebound effect.

Adult↗

PubMed1975

Effects of dixyrazine and methaqualone on the sleep pattern in normal man.

Whole night EEG and polygraphic recordings were made in ten young, healthy, male volunteers after dixyrazine (12.5 mg, 25 mg, 50 mg), methaqualone (250 mg) and Isonox (methaqualone 250 mg + etodroxizine 50 mg). A total of 156 recording nights (36 adaptation nights were not included in the analyses) were scored for different sleep stages according to accepted criteria. The smallest dose of dixyrazine (12.5 mg) had no significant effect upon sleep pattern: the larger doses (25 mg and 50 mg) caused significant decreases in REM-sleep during the first nights of administration. The decrease disappeared during the following two nights of treatment. No withdrawal effects were seen. Methaqualone also caused moderate depression of REM-sleep during the first night of treatment, and this effect, too, disappeared during prolonged administration. Isonox (methaqualone + etodroxizine) had a somewhat stronger surpressive effect upon REM-sleep than methaqualone alone.

Adult↗

PubMed1975

Guanidine and neuromuscular transmission. I. Effect on transmitter release occurring spontaneously and in response to single nerve stimuli.

The effect of guanidine on neuromuscular transmission was studied in human intercostal muscle and mouse diaphragm preparations in vitro. Guanidine greatly increased the number of acetylcholine (ACh) quanta released by a single motor nerve action potential. This effect of guanidine was greater at junctions with a low quantum content. The spontaneous release of ACh quanta was not substantially changed by guanidine. No change was found in the postsynaptic sensitivity to ACh released from the motor nerve or iontophoretically applied to the muscle fiber. Effects of the drug had slow onset and were very long-lasting and resistant to wash.

Acetylcholine↗

PubMed1975

Guanidine and neuromuscular transmission. II. Effect on transmitter release in response to repetitive nerve stimulation.

The effect of guanidine on the neuromuscular transmission in human intercostal and mouse diaphragm muscle in vitro during repetitive nerve stimulation was studied. The drug greatly increased the release of acetylcholine (ACh) quanta by nerve impulses at low frequencies of nerve stimulation and at the beginning of tetani at high frequencies of stimulation. The effect was shown to be produced by an increase in fractional release from an unchanged store of ACh quanta available fro immediate release. This seems to explain why guanidine has a poor therapeutic effect in myasthenia gravis but a good effect in the myasthenic syndrome.

Acetylcholine↗

PubMed1975

Postirradiation syndrome and eeg findings in children with acute lymphoblastic leukaemia.

Out of 12 children with acute lymphoblastic leukaemia treated with craniospinal irradiation during primary haematologic remission, 8 developed a postirradiation syndrome characterized by fever and tiredness. The symptoms lasted 1-2 weeks and subsided spontaneously. Longitudinal EEG studies revealed no acute disturbances during the irradiation therapy but in all cases studied, moderate to severe diffuse general slowing developed during the postirradiation syndrome. Complete normalization of the EEG occurred in all children at follow-up. It is concluded that the described EEG abnormalities constitute an integral part of the postirradiation syndrome.

Adolescent↗

PubMed1975

Motor pauses in EMG activity during chewing and biting.

Biting on hard particles during chewing sometimes produced motor pauses but more often abrupt atypical terminations of the EMG patterns occurred. A series of tests with different experimental biting and chewing situations were performed. The results indicate that the motor inhibition that occurs during biting and chewing mainly are of two different origins. The inhibition that occurs during tooth tapping and biting on hard particles is caused by tendon and muscle stretching occurring as a result of the mechanical stop of the jaw movement. The inhibition occurring when crushing a brittle bolus has a different origin and occurs before tooth contact and is a form of unloading reflex. The periodontal receptors or surface sensibility appears to be of minor importance for these types of motor inhibition.

Electromyography↗

PubMed1974