The relationship between nitrous oxide conscious sedation and the hypnotic state

To evaluate the hypothesis that inhalation of low levels of nitrous oxide-oxygen produces an altered state of consciousness similar to hypnosis, 20 subjects were given three suggestions (analgesia, compulsive behavior, and amnesia) during double-blind administration of either nitrous oxide-oxygen or oxygen. Results suggest that administration of nitrous oxide-oxygen may be of increased clinical usefulness if it is combined with careful use of suggestion.

Teratogenic effects of diazepam in the hamster

Pregnant hamsters were treated with different doses of oral and intravenous diazepam during the period of organogenesis. Teratogenic effects of diazepam were observed following oral treatment on days 8 and 10 and following intravenous treatment on day 11 of gestation. Types of malformations included cleft palate, exencephaly, limb anomalies, and hemorrhage. A dose-effect relationship was not observed. Comparison with reported literature seems to indicate that diazepam may be a mild teratogen in some species.

Specificity of chromatin transcription in vitro. Anomalies due to RNA-dependent RNA synthesis

In the presence of Mn2+, globin mRNA can be transcribed into a partial RNA copy by Escherichia coli RNA polymerase. This process also occurs when the mRNA is transcribed together with chromatin. A fraction, at least, of the newly synthesized RNA copy (anti-globin RNA) can serve as a template for the synthesis of globin sequences of the same polarity as the original mRNA. This process is sufficient to explain the specific synthesis of a subset of the globin RNA on mouse foetal liver chromatin. It also accounts for the synthesis of double-stranded RNA sequence by E. coli RNA polymerase, on chromatin as well as on pure mRNA. Results are presented suggesting that the poly(A) tract of the mRNA could be preferentially transcribed. In the presence of Mg2+, the RNA-dependent transcription is strongly inhibited, as well as the synthesis of double-stranded RNA. Under these conditions, the transcription on chromatin appears to be largely DNA dependent, and the synthesis of globin sequences is completely asymmetric. Spermine (0.3 mM) seems to improve the specificity of transcription. The transcription of chromatin in vitro is thus largely dependent on the nature of the divalent cation present in the in the incubation mixture.

A review of the effects of diazepam on cognitive and psychomotor performance

Studies evaluating the effects of diazepam (Valium) on psychomotor and cognitive functions are reviewed an integrated. The importance of the full and clear documentation of such drug effects lies in the wide usage of diazepam today for a variety of medical, psychiatric, and dental purposes. The various tasks used to assess drug effects were classified into six major groups based on apparent similarity of functions tapped. These groupings are: reflex speed; critical flicker fusion threshold; attention and vigilance; decision making; learning and memory; psychomotor performance. In all functions except simple reflexive responding; some indications of impaired performances were reported, the results being most definitive for the critical flicker fusion where even small doses lowered the threshold and for a slower performance on letter cancellation tasks. There appeared to be some interaction between diazepam and alcohol although the nature of this interaction is still unclear. Because of the extensive use of both of these drugs and the possibility of a synergistic or a potentiation effect, it is important that this area receive further study. It was suggested that future studies either control for or analyze the data to assess the possible interactive effects of diazepam with subject variables such as sex, personality type, and for population characteristics. These variables have been shown to affect responses in other studies and hence could also interact with cognitive and psychomotor performance. It was noted that most of the studies reviewed used normal, healthy, male volunteer subjects and may not be comparable to the clinical populations for whom the drug is typically prescribed.

An assessment of serum 57Co cyanocobalamin as an index of vitamin B12 absorption

A technique has been developed for accurately assaying serum and urine (57)Co cyanocobalamin during the conventional Schilling test. Serum and urine radioactivity in a large number of patients has been correlated and the precise normal limits have been determined by statistical analysis. The implications of this for investigating conditions other than pernicious anaemia and the malabsorption syndromes are stressed.

Vitamin B12 absorption in some neurological and neuroendocrine disorders

An assessment of vitamin B(12) absorption in neurological patients has been made by both serum and urine counting of (57)Co cyanocobalamin during the conventional Schilling test. Although patients with pernicious anaemia, some with subacute combined degeneration of the cord, have been studied, emphasis in the discussion is placed on the significantly increased excretion of the radioactive vitamin in a group of patients with pituitary insufficiency. Results are also given for epileptic patients who have developed folate deficiency (as assessed by serum folate levels) coincidental with anticonvulsant therapy, as well as for some patients who have had neurological symptoms or signs following partial gastrectomy operations.