Some newly reported research results indicate that slightly abnormal biological rhythms, both long- and short-term, may be key factors in the development of depression and manic-depression. The results may also hold clues about why certain drugs work or fail to work with different individuals. (Author/BB)

Discusses different foods with reference to oxidation and energy production. Amino acid assays are provided for eggs, steak, rice, and lentils and white and dark turkey meat is analyzed for energy and power outputs. (MA)

Recent studies done by federal researchers indicate that human aggression may be affected by a critical balance of two or three key brain chemical neurotransmitters. Results of this study with human beings are included in this article. (MA)

The author explains that misunderstanding the role of science and scientists is mainly due to a communication gap precipitated by the enormity of the field of science. Among the many examples given are cloning and DNA from biomedical research. Argues strongly against establishing an agency to control the field of scientific research. (GA)

A discussion is presented of the toxicity, chemistry, and environmental presence of nitrosamines. Carcinogenicity and effects on various organs of test animals are reviewed. Also some information on the presence of use of nitrosamines in human food is given. (MR)

A plant protoplast is basically a plant cell that lacks a cell wall. This article outlines some of the ways in which protoplasts may be used to advance understanding of plant cell biology in research and student instruction. Topics include high efficiency experimental virus infection, organelle isolation, and osmotic effects. (Author/MA)

Reviews much of what is known about microtubules, which are biopolymers consisting predominantly of subunits of the globular protein, tubulin. Describes the functions of microtubules, their structure and assembly, microtube associated proteins, and microtubule-disrupting agents. (TW)

Cocaine and nicotine are among stiumulants used by athletes to improve their performance or for escape. Negative effects of these stimulants are discussed. (Author/CB)

Discusses the structure and function of the liver protein cytochrome P-450, an important catalyst for a variety of detoxification reactions. Diagnostic substracts for this heme-containing monooxygenase, synthetic modes of the active site, and oxidations with synthetic metalloporphyrins are the major topic areas considered. (JN)

Discusses model studies aimed at elucidating various ways in which molecular oxygen interacts with metalloproteins. The focus is on the chemistry of iron(II) porphyrins and their adducts with nitrogenous bases, carbon monoxide, and dioxygen, which are most relevant to the functional proteries of the heme proteins, hemoglobin, and myoglobin. (JN)

Reviews current findings that explain RNA's function as an enzyme in addition to being an informational molecule. Highlights recent research efforts and notes changes in the information base on RNA activity. Includes models and diagrams of RNA activity. (ML)

Cytoplasmic proteins form a highly structured yet changeable matrix that affects cell shape, division, motion, and transport of vesicles and organelles. Types of microfilaments, research techniques, actin and myosin, tumor cells, and other topics are addressed. Evidence indicates that the cell matrix might have a bearing on metabolism. (DH)

Discusses (1) polyproptic acids for which the difference between K-a's is large; (2) the Henderson-Hasselbach equation; (3) polyprotic acids for which the difference between K-a's is small; (4) analysis of microscopic dissociation constants for cysteine; and (5) analysis of pK-a data. (JN)

Describes the nature of affinity chromatography and its use in purifying enzymes, studying cell interactions, exploring hormone receptors, and other areas. The potential the technique may have in treating disease is also considered. (JN)

Discusses: (1) characteristic initial velocity behavior (considering the five-step reaction sequence for rapid equilibrium-order bisubstrate mechanisms); (2) dead-end inhibition; (3) inhibition by single products; and (4) an activator as a leading reactant. (JN)