Enzymatic conversion of sterigmatocystin into aflatoxin B1 by cell-free extracts of Aspergillus parasiticus

A cell-free extract, prepared from Aspergillus parasiticus ATCC 15517 grown in synthetic medium, was active in converting [14C]sterigmatocystin into aflatoxin B1 in the presence of reduced nicotinamide adenine dinucleotide phosphate. The activity was demonstrated by the time course of conversion and the linear dependence of the yield of product on enzyme concentrations. Optimum activity was obtained at pH 7.5 to 7.8 at 27 C. The results confirm sterigmatocystin as a biogenetic precursor of aflatoxin B1. Techniques were developed for enzymatic studies on aflatoxin biosynthesis.

A longitudinal study of the growth of trunk surface area measured by planimeter on standard somatotype photographs

Thoracic and abdominal surface areas have been measured by planimeter on 340 photogrammetric somatotype photographs of 15 boys of the Harpenden Growth Study followed at regular intervals from 3 to 20 years of age. Mean distance and velocity curves are given, estimated by Patterson's method for extracting maximum information from mixed longitudinal data. Both areas showed a marked adolescent growth spurt with the age at peak coinciding with the age of peak height velocity of the same children. The correlation coefficients between thorax and abdominal surface areas rose from an average of about 0-3 at ages 5-8 to 0-5 at ages 9-12 and 0-7 at ages 13-19. Trunk index (thorax/abdomen area) fell gradually with age from 5 to 9 and thereafter remained constant.

Experience with allografts in the surgery of peripheral nerves (experimental study)

Peroneal nerve allografts four to seven cm in length were transplanted in 36 tissue typed beagle dogs, using a standard microsurgical technique. The influence of tissue typing on nerve regeneration through these grafts was studied with the help of electromyography and histology seven to nine months after nerve implantation. Better regeneration was found through the grafts with compatible than with noncompatible typing. The favourable effect of tissue compatibility became more evident when the length of the graft was longer than four cm. Tissue rejection reaction was much more marked and evident with longer grafts in noncompatible than in compatible groups. Radiation, with tissue typing, did not seem to confer any additional beneficial effect. Compatible tissue typed nerve allografts probably behave more like autografts.

Mercury(II) cyanide complexes with 4,4'-Bipyridine and 4,4'-(Propane-1,3-diyl)-bispyridine

1:1 Coordination complexes formed by mercury(11) cyanide with 4,4'-bipyridine and 4,4'-(propane-1,3-diyl)bispyridine have been prepared and characterized by molar conductance, molecular weight and infrared spectral measurements down to 200 cm-1 in the solid state. The 4,4'-bipyridine complex is shown to have a polymeric chain structure with a tetrahedral environment of two nitrogen atoms of bridging 4,4'-bipyridine and two carbon atoms of the terminally bonded cyano groups about the mercury atoms. The 4,4'-(propane-1,3-diyl)bispyridine complex is suggested to have a monomeric three-coordinate structure with only terminally bonded 4,4'-(propane-1,3-diyl)bispyridine and cyano groups.

Microbiology of cutaneous tuberculosis

Detailed bacteriological characteristics including drug sensitivity of 12 mycobacteria isolated from 51 cases of different types of cutaneous tuberculosis were studied; no mycobacterium could be isolated from remaining 39 cases. Nine were identified as M. tuberculosis and 3 as 'anonymous' mycobacteria. Acquired resistance to one or more than one drug (streptomycin, isoniazid, PAS and thiacetazone) was observed in 3 out of 9 strains of M. tuberculosis. All the 'anonymous' strains were resistant to all the drugs except ethionamide and ethambutol.

Hypothalamic stimulation of prolactin release in a freshwater catfish, Heteropneustes fossilis

Hypothalamic extract has been found to contain certain factor(s) which triggers the release of prolactin from the pituitary gland. In assay recipients, hypothalamic extract injection was as effective as perphenazine-HCl treatment in triggering the release of prolactin from pituitary gland. Rise in prolactin concentration of serum and resultant decrease in pituitary prolactin level in response to hypothalamic extract administration suggests that hypothalamus in H. fossilis has prolactin releasing factor(s). This releasing effect of hypothalamus seems to be specific since cortical extract injections were ineffective in producing the similar response.

Lysozyme in corneal ulcer

In the present experimental study the role of lysozyme drops in healing of corneal ulcer of staphylococcal origin (sensitive to chloramphenicol) was studied on 16 albino rabbits. In 8 rabbits, in one eye placibo drops (distilled water) and in the other eye lysozyme 1% were put 4 times daily. In the other 8 rabbits, in one eye chloramphenicol drops 0.4% and in the other eye chloramphenicol drops 0.4% + lysozyme drops 1% were instilled 4 times daily. It was observed that the rate of healing of corneal ulcer was much earlier in the eyes which had local instillation of chloramphenicol drops + lysozyme in comparison to the eyes which had only chloramphenicol drops, lysozyme drops, or distilled water.

Traumatic left ventricular aneurysm. Two cases with normal coronary angiograms

Two young males had traumatic left ventricular aneurysm and normal coronary angiograms. Trauma was penetrating (bullet) in one and nonpenetrating (fist blow) in the other. Recurrent ventricular tachycardia in one and a systemic embolus in the other required aneurysmectomy. The patients are free of symptoms 42 and 21 months after surgery. The presence of traumatic ventricular aneurysm and normal coronary angiograms suggests that myocardial necrosis following chest trauma is often caused by direct injury to the myocardium rather than by injury to occlusion of the coronary arteries. Therefore, coronary artery bypass surgery may be unnecessary or even hazardous in persons with chest trauma and evidence of early myocardial necrosis.

Personal evaluations, laughter, and affective judgments

Fifty-six subjects read positive or negative evaluations of their personality made by a bogus same-sex peer and then rated their immediate feelings. A second group of 22 subjects rated their feelings after reading the evaluations of a third person. It was found that personal evaluations evoked more spontaneous laughter than did the evaluation of a third person (p less than .001). Inclusion of the factor of laughter in the experimental design disclosed that subjects who laughed felt more pleasant than those who did not laugh (p less than .008) and that laughter was associated with affective state only in the negative evaluation condition (p less than .003).. Also, positive evaluations made the subjects feel good, and negative ones made them feel bad (p less than .001). Results seemed to suggest that extreme affective arousal engenders laughter which, in turn, alters the judgments of one's affective state.

H3-phenylalanine incorporation into protein in the pituitary, hypothalamus and cerebral cortex of male rats during postnatal development

Incorporation of H3-phenylalanine and concentration of protein in the anterior pituitary gland (APG), hypothalamus and cerebral cortex of male rats have been studied during postnatal development from day 21 to 120. APG and hypothalamus showed significantly higher rate of amino acid uptake and protein synthesis during the prepubertal phase, decrease at puberty and an age dependent variation thereafter. Protein concentrations and amino acid incorporation in the APG and hypothalamus are possibly influenced by the higher circulating levels of androgens during sexual maturation in marked contrast to their lack of effect on the cerebral cortex.

Experience with homologous lyophilised nerve grafts in the treatment of peripheral nerve injuries

Report of a series of 18 late secondary nerve grafts using lyophilised (disantigenised and disenzymatised) homografts of the Braun Melsungen Company. In contrast to the publication of Kuhlendahl et al. (1972) 32% of the cases showed definitive signs of regeneration. Therefore, in spite of the fact that autografts give better results, further research into the possibilities of homografts seems desirable. Their potential usefulness obviously is restricted to cases in which from any reasons autologous nerve grafts are not available.