Ganglionic blockade by procaine in the presence of pentobarbital and diethyl ether.

The interactions of procaine with pentobarbital and diethyl ether were observed on the isolated stellate ganglion of the hamster. Each drug reduced the amplitude of the compound postganglionic action potential induced by stimulation of the preganglionic nerve at 0.2 Hz. The slopes of the concentration response curves were not significantly different for the three drugs. When solutions of procaine and pentobarbital were mixed, the effect of the mixture was not significantly different from the effects of procaine and pentobarbital solutions, separately. Also, procaine shifted the concentration-response curve for pentobarbital in a manner expected for an additive interaction. When solutions of procaine and diethyl ether were mixed, the blockade by the mixture was significantly greater than the blockade by procaine and diethyl ether solutions, separately. Procaine shifted the concentration-response curve for diethyl ether in a manner that is greater than would be expected for an additive interaction. These results indicate that procaine and pentobarbital interact, additively, and that procaine potentiates the actions of diethyl ether. The potentiating interaction of procaine and diethyl ether suggests that the drugs have different mechanisms of action on the ganglion.

Gulf Stream Ring Coalescence with the Gulf Stream off Cape Hatteras.

A cyclonic ring, which had separated from the Gulf Stream 7 months earlier and traveled 500 kilometers westward, collided with the stream in September 1977. Within 3 days the ring and stream joined to form a sharp S-shaped meander. Shipboard expendable temperature probes and four bottom-moored inverted echo sounders were used to obtain synoptic descriptions of the rejoining process.

Poly(glycolic acid) sutures in canine vascular anastomoses.

Poly(glycolic acid) (Dexon; Davis and Geck Company) canine vascular anastomoses between aorta and synthetic grafts and between severed femoral vessels were compared with comparable anastomoses made with Teflon-coated Dacron (Tevdek; The Deknatel Company) with respect to clinical performance, morphologic characteristics, and tensile strength. While the Dexon anastomoses performed well and were morphologically superior to Tevdek, their tensile strength was significantly lower. Implications of these findings for vascular wound healing are discussed.