Some Observations on Myocardial Revascularization

Since 1929 various surgical procedures have been devised to revascularize the ischemic heart to provide it with blood from extracoronary sources. A comparative study has been carried out in 80 mongrel dogs over a two-year period to evaluate the relative merits of cardio-omentopexy, left atrial pulmonary artery anastomosis and the Ivalon sponge operation. The Ivalon sponge procedure proved to be most effective in relieving artificially produced myocardial ischemia. The procedure has subsequently been carried out in two patients with crippling angina pectoris, and a complete relief of symptoms has been achieved in both.     

Some Observations on Glass-Knife Making

The yield of usable knife edge per Me (for thin sectioning) was markedly increased when glass knives were made at an included angle of 55° rather than the customary 45deg;. A large number of measurements of edge check marks made with a routine light scattering method as well as observations made on a smaller number of test sections with the electron microscope indicated the superiority of 55° knives. Knives were made with both taped pliers and an LKB Knifemaker. Knives were graded by methods easily applied in any biological electron microscope laboratory. Depending on the mode of fracture, the yield of knives having more than 33% of their edges free of check marks was 30 to 100 times greater at 55° than 45°.     

Observations on Some Chrysomonads from Scotland

SYNOPSIS. The taxonomy of the genera Mallomonas, Mallomonopsis and Synura is based on their silica scales. Examination of water samples from Southern Scotland in the electron microscope revealed that they were plentiful in the area and permitted detailed observations on new species. Comparative studies are made on the flagella of three known species of Synura ; the "flimmergeissel" of these biflagellates appear to be more or less similar, but the whip-lash flagella show specific differences suggesting a possible secondary taxonomic criterion. The distribution of the three genera is discussed with particular reference to species found in Iceland, Scotland and Japan. A stage in the conjugation of a species of Mallomonas is described.