Ultrasound placement of cardiac tube in ventricular atrial shung. Technical note

✓ A new technique using an ultrasonic probe for accurate placement of the cardiac tube in a ventriculoatrial shunt is described. This method provides correct measurement of the distance between the tube tip and the pulsating tricuspid valve.

Production of nuclease-formine 5'-nucleotide by Aspergillus quercinus in a low phosphate medium

The production of ribonucleic acid (RNA)-depolymerase-forming 5'-nucleotides (5'-nuclease) was investigated with the fungus Aspergillus quercinus in media containing 68, 10, 5, 3, 1, and 0.5 mg of phosphorus per 100 ml. Yields were maximal with 5 mg of phosphorus per 100 ml. RNA-depolymerase-forming 3'-nucleosides (3'-nuclease) and phosphomonoesterase were maximal in media containing 1 and 0.5 mg of phosphorus per 100 ml. The 5'-nuclease was purified approximately 530-fold with a recovery of 84% by column chromatography on diethylaminoethyl-cellulose and by gel filtration through Sephadex G-100. The purified enzyme was capable of acting on both deoxyribonucleic acid and RNA, and the 5'-mononucleotides produced were identified by paper chromatography. The enzyme 5'-nuclease appears to be one of the repressible exonucleases that are active in the production of 5'-mononucleotides.

Production of phosphatase by Aspergillus awamori var. kawachii in a low phosphate medium

The effect of phosphate on the production of phosphatases by Aspergillus awamori var. kawachii was studied. In a high phosphate medium, little phosphatase was produced, and the phosphatase activity was predominately for beta-glycerophosphate. In a low phosphate medium, the production of phosphatase was increased and activity for glucose-6-phosphate predominated. Medium containing 1 mg of phosphorus per 100 ml was optimal, and the amount of phosphatase produced in this medium was about 200 times that produced in a high phosphate medium. By means of column chromatography on diethylaminoethyl cellulose, the phosphatase produced in the high phosphate medium was found to be eluted mainly at fraction e; the phosphatase of the low phosphate medium was separated into fractions a, b, c, and d. Thus, the phosphatase fractions produced in the low phosphate medium were different from those of the high phosphate medium. Since no specific effect on the production of esterases was observed when various phosphate esters were used as substrates, the enzymes of phosphate metabolism appear to be activated by nonspecific phosphate sources.

Hemoglobin sealy (alpha 2-47His-beta 2): a new variant in a Jewish family

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