The various forms of pulmonary varices. Report of three cases and review of the literature

Ture pulmonary varices are congenital local dilatations of a pulmonary vein or veins, with normal or collateral transpulmonary drainage into the left atrium. Pulmonary varices do not cause pulmonary venous hypertension, but existing varices can further become dilated by pulmonary venous hypertension due to mitral valve disease. Embryologically, pulmonary varices may represent residual primitive splanchnic venous components incorporated into the pulmonary venous system, or atresia of an individual pulmonary vein which occurred at a time that enable adoption of unobstructed transpulmonary collateral drainage into the left atrium. True pulmonary varices do not produce symptoms, do not change in diameter over the years, and, usually, do not require treatment.

Lethal effect of fresh sea water on Vibrio parahaemolyticus and isolation of Bdellovibrio parasitic against the organism

Halophilic Bdellovibrio, which is parasitic and lytic to Vibrio pharahaemolyticus, was ioslated from fresh sea water in the winter. It had a lethal effect on V. parahaemolyticus. The optimum temperature ofr multiplication ranged from 25 C to 30 C and growth was not observed at 35 C. Plaque numbers of the isolate reached a maximum in 17 hr under conditions of shaking at 25 C in autoclaved sea water supplemented with V. parahaemolyticus cells, and were as high as ten times the number of host cells. With respect to the host-suspended medium, the isolate multiplied in natural sea water ten times more than in Herbst's artificial sea water but did not grow in saline. V. parahaemolyticus, Vibrio alginolyticus and several species in the Vibrio genus were susceptible to the parasite on the basis of plaque formation but Escherichia coli and Staphylococcus aureus were not.