FACTORS INFLUENCING BRAIN AND TISSUE LEVELS OF TRYPTAMINE: SPECIES, DRUGS AND LESIONS

With a modification of the spectrophotofluorometric (SPF) method of HESS & UDENFRIEND (1959) (J. Pharmac. exp. Ther. 127 , 175-177), brain tryptamine levels in the rat (20.9 ng/g) and guinea-pig (20.7 ng/g) were found to be less than those in the dog (32.1 ng/g) and cat (52.2 ng/g). Regional distribution studies in the dog and cat showed that tryptamine was present in all major brain regions with highest concentrations in the spinal cord. Blood levels of tryptamine in the guinea-pig, dog and cat (6-7 ng/ml) were lower than brain levels. Pargyline significantly increased brain tryptamine in both the dog and cat; whereas, isocarboxazid (after 4 h) increased brain tryptamine levels in the dog but decreased brain levels in the cat. Reserpine (0.5-1.0 mg/kg per day for 1-4 days) did not significantly decrease brain, spinal cord or blood tryptamine levels in the dog. Spinal cord transection did not decrease tryptamine levels below the lesion in the chronic spinal dog.     

Products of complementation between temperature-sensitive mutants of simian virus 40.

Temperature-sensitive mutants of the D complementation group of simian virus 40 exhibit delayed complementation. Analysis of the thermal stability, kinetic profiles in temperature shift experiments, and progeny of complementation have led to the hypothesis that delayed complementation is not true complementation, but the result of a very low level of leakiness, followed by phenotypic mixing of the progeny D mutants. This hypothesis is consistent with the proposal that D mutants are defective in uncoating. In the course of these experiments, it was observed that fresh medium suppresses the growth of D mutants at the restrictive temperature.     

Vaginally administered 16, 16-dimethyl-prostaglandin E2 as an agent for pre-operative cervical dilatation.

Twenty-one women in the 10th-12th week of pregnancy were treated prior to vacuum aspiration with vaginal suppositories containing 16, 16-dimethyl-PGE2 (free acid). An average total dose of 3.4 mg led to abortion or adequate cervical dilatation in all patients. Based upon previous experience with the compound, no prophylactic anti-emetic or anti-diarrhetic medication was given. Gastrointestinal side effects were minimal. Excessive bleeding was not observed. In two cases, slight temperature elevation was noted prior to abortion. The low incidence of side effects in combination with the effectiveness of the compound help to make this method an attractive therapeutic adjunct to vacuum aspiration beyond the 10th week of gestation. Under the experimental conditions of this study, the results suggest that vaginally administered 16, 16-dimethyl-PGE2 can be a safe and effective method for cervical dilatation before vacuum aspiration.     

Variegated translocation mosaicism in human skin fibroblast cultures.

The term "variegated translocation mosaicism" is used to describe the repeated occurrence, within cultures of human skin fibroblasts, of a multiplicity of chromosomal rearrangements. With respect to the frequencies of such cytogenetically aberrant clones we found that they (1) were not detectable in routine diagnostic skin fibroblast cultures from 29 subjects with a wide variety of indications for biopsy; (2) were not detectable during in vitro aging of diploid strains with four normal individuals; (3) could be detected after rescue from bacterial contamination of a culture from an otherwise normal diploid male; (4) occurred with high frequencies in independent cultures from another apparently normal subject; (5) occurred with high frequencies in multiple biopsies obtained at autopsy from a patient with Werner's syndrome who died of sepsis; (6) were of pseudodiploid nature; and (7) involved a different spectrum of chromosomes in different individuals. A consistent association with mycoplasma contamination could not be made.     

Conversion of covalently mercurated nucleic acids to tritiated and halogenated derivatives.

Mercurated nucleic acids are converted to the corresponding tritiated, brominated, and iodinated derivatives by treatment with sodium borotritiide, N-bromosuccinimide, and elemental iodine, respectively. All three reactions occur under mild conditions in neutral aqueous solutions. Mercury-halogen conversions are essentially quantitative at both the mono- and polynucleotide levels. Tritiation reactions also proceed efficiently with mononucleotides, although polymers undergo incomplete demercuration. In spite of the latter limitation , these reactions provide novel and efficient synthetic routes to radiolabeled nucleic acid derivatives.     

Angular sensitivity of light and dark adapted locust retinula cells

Summary Angular sensitivity functions for light and dark-adapted locust retinula cells have been measured. The angular sensitivity for light-adapted cells follows a Gaussian function but in the dark-adapted condition the measured function is broader than Gaussian at its base. Acceptance angles for light-adapted cells are 1.5°±0.2° (horizontal), 1.4°±0.1° (vertical) and for dark-adapted cells, 2.4°±0.5° (horizontal) and 2.5°±0.4° (vertical). These values are significantly smaller than those previously reported and show the locust eye to be closer to its theoretical limit of resolution than was previously indicated.The angular sensitivity of light-adapted cells agress well with the minimum resolvable stripe period reported by those authors refuting anomalous resolution.     

Pericarditis,pleural effusion,and pneumonitis with transient mitochondrial antibodies.

Four women with fever, arthromyalgias, pericarditis, pleural effusion, high erythrocyte sedimentation rates, and lymphopenia had mitochondrial antibodies in the serum in the absence of antinuclear antibody. Their illness lasted 5-12 weeks and the antibody test results became negative on remission. Absence of specific bacteriological findings, normal antistreptolysin O titres, resistance to antibiotics, and good response to steroids suggested that these cases represented a milder and less persistent form of the syndrome resembling systemic lupus erythematosus described by German authors.