The effects on sexual behavior of opiate receptor stimulation within A10 and A14 terminal areas were examined in the following experiments. Morphine (0.01-6 nmol) and dynorphin(1-13) (0.01-3 pmol) were microinjected into the medial preoptic area (MPOA). Morphine (10-100 pmol) and dynorphin (10-100 fmol) injected into the MPOA reduced both the latency to ejaculate and the number of intromissions...

CommunIcations to the Editor genesis ofthe pulmonary edema in this patient. Indeed, endorphins are released in stress situations and they can adversely affect physiologic systems, such as respiration and circulation.’ In the human fetus at term, plasma levels of beta-endorphins and betaLPH are inversely correlated with arterial pH and Po5 suggesting that hypoxia and secondary acidosis may be im...

A method is described for using the cross-linking reagent 4'-(hydroxy-methyl)-4,5',8-trimethylpsoralen (HMT) to map base paired regions and higher-order structure within RNA molecules. Applying this method to yeast tRNAPhe, we have specifically identified cross-links within the acceptor stem between U6 X U68, in the D-stem between C11 X C25, and in the T psi-stem between U50 X C63 and U52 X C63...

Since the introduction of the short acting muscle relaxant succinyl dicholine (suxamethonium) in 1951 and the subsequent discovery that certain patients exhibited a greater than usual sensitivity to the drug, interest has been directed towards identifying the genetically controlled variants of serum cholinesterase (acylcholine acyl hydrolase E.C. 3.1.1.8). Some of these variants have been found...

Recognition of tRNA by the cognate aminoacyl-tRNA synthetase during translation is crucial to ensure the correct expression of the genetic code. To understand tRNA(Leu) recognition sets and their evolution, the recognition of tRNA(Leu) by the leucyl-tRNA synthetase (LeuRS) from the primitive hyperthermophilic bacterium Aquifex aeolicus was studied by RNA probing and mutagenesis. The results sho...

Eukaryotic RNA polymerase I (Pol I) is specialized in rRNA gene transcription synthesizing up to 60% of cellular RNA. High level rRNA production relies on efficient binding of initiation factors to the rRNA gene promoter and recruitment of Pol I complexes containing initiation factor Rrn3. Here, we determine the cryo-EM structure of the Pol I-Rrn3 complex at 7.5 Å resolution, and compare it wit...

We examine the dynamic formation and stochastic evolution of networks connecting individuals. The payoff to an individual from an economic or social activity depends on the network of connections among individuals. Over time individuals form and sever links connecting themselves to other individuals based on the improvement that the resulting network offers them relative to the current network....

* The authors gratefully acknowledge the helpful comments and guidance of Don Chew, Bob Daigler, Jayant Kale, and Isabel Tkatch, and the research assistance of Anna Agapova, Laetitia Dowd, and Tonmoy Navare. 1. See Merton H. Miller and Christopher L. Culp, “The SEC’s Costly Disclosure Rules,” Wall Street Journal, June 25, 1996, p. A14. 2. See Christine Botosan, “Evidence That Greater Disclosure...