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Profiles 50-year-old creator of `habitat sound portraits,' Bernie Krause, who owns Parasound and has spent the last 20 years compiling the world's preeminent private collection of environmental recordings. Personal and career.

Butyrylcholinesterase [BuChE (acylcholine acyl hydrolase); EC 3.1.1.8] limits the access of drugs, including tacrine, to other proteins. The "atypical" BuChE variant, in which Asp70 at the rim of the active site gorge is substituted by glycine, displayed a more drastically weakened interaction with tacrine than with cocaine, dibucaine, succinylcholine, BW284c51 [1,5-bis(4-allyldimethylammoniumphenyl)pentan-3-one dibromide], or alpha-solanine. To delineate the protein domains that are responsible for this phenomenon, we mutated residues within the rim of the active site gorge, the region parallel to the peripheral site in the homologous enzyme acetylcholinesterase [AChE (acetylcholine acetyl hydrolase); EC 3.1.1.7], the oxyanion hole, and the choline-binding site. When expressed in microinjected Xenopus laevis oocytes, all mutant DNAs yielded comparable amounts of immunoreactive protein products. Most mutants retained catalytic activity close to that of wild-type BuChE and were capable of binding ligands. However, certain modifications in and around the oxyanion hole caused a dramatic loss in activity. The affinities for tacrine were reduced more dramatically than for all other ligands, including cocaine, in both oxyanion hole and choline-binding site mutants. Modified ligand affinities further demonstrated a peripheral site in residues homologous with those of AChE. BuChE mutations that prevented tacrine interactions also hampered its ability to bind other drugs and inhibitors, which suggests a partial overlap of the binding sites. This predicts that in addition to their genetic predisposition to adverse responses to tacrine, homozygous carriers of "atypical" BuChE will be overly sensitive to additional anticholinesterases and especially so when exposed to several anticholinesterases in combination.

Since innate resistance of mice to Salmonella typhimurium depends on an intact macrophage system, we have used this bacterium to investigate the effect of Trypanosoma brucei subsp. rhodesiense infection on macrophage phagocytic and cytolytic function. CBA/CaJ mice infected with T. brucei subsp. rhodesiense have decreased resistance to S. typhimurium, since doubly infected mice rapidly succumb to sublethal doses of S. typhimurium. Although trypanosomiasis is known to suppress antibody formation, such a suppression of antibody does not seem to play a role in trypanosome-induced sensitivity to S. typhimurium. A trypanosome-induced blockade of the reticuloendothelial system also does not occur, since parasitized and control mice clear S. typhimurium from the blood equally well. Early killing (0 to 48 h) of S. typhimurium in the liver and spleen is mainly macrophage mediated, and mice infected with trypanosomes kill S. typhimurium in the liver and spleen very poorly. Apparently trypanosomiasis inhibits macrophage bactericidal activity, but has no effect on phagocytosis.

The quantitative histologic distribution of pyridoxal phosphate (PLP), the coenzyme of histidine decarboxylase in the biosynthesis of histamine as well as the coenzyme of other enzyme systems, was established in the rat glandular stomach in different secretory states. This was accomplished by analyzing PLP with an improved fluorometric microprocedure in histologically identified fresh-frozen microtome tissue sections cut serially through the stomach wall of fed and 24-hr fasted rats, and of the latter injected with drugs that stimulate (histamine, theophylline and urecholine) or inhibit (atropine) secretion. In fasted compared with fed rats, and in fasted rats injected with histamine (low dose) or theophylline, compared with saline injected controls, the PLP level was reduced not only in the chief cell region where PLP is utilized in histamine production, but also in the parietal and mucous neck cell region, indicating PLP function in other enzyme systems in these sites. No change in PLP level occurred when histamine was injected at a high dose known to suppress histidine decarboxylase activity. Administration of urecholine or atropine had negligible effect on the PLP levels, indicating a lack of vagal stimulatory or inhibitory influence.

The rapid growth of laser technology and applications makes it necessary to consider relevant factors of safety, in addition to eye protection, which has been well recognized. In the use of the laser microprobe for medical studies, biological samples are vaporized by a high-energy pulsed laser beam which can cause formation of aerosols and splattering of the sample material. In this study the hazard that can result was shown by the use of bacterial colonies and bacterially infected serum and tissue samples which were vaporized by the laser beam. Viable organisms were recovered from both the aerosols and the splattered material. Circumvention of the hazard from contact or inhalation of such infective material was considered.

Recent biochemical studies on the functional zonation of the human adrenal cortex suggest that one of the earlier principal effects of corticotrophin (ACTH) on steroid biosynthesis occurs at the fasciculo-reticular border. This report deals with procedures for the study of the 11β-hydroxylase activity in microgram amounts of adrenal tissue and with the distribution of this activity throughout the adrenal cortex of the rat. ACTH administration is shown to stimulate the 11β-hydroxylase activity at the fasciculo-reticular border.

Reports that there are many homosexuals in the armed services and they want to come out of the closet. Comments from Rep. Patricia Schroeder; Recent actions at the Department of Defense (DOD); Actions of Naval Lt. Tracy Thorne; Comments made by Defense Secretary Dick Cheney; Case of Jerald Johnson and the Federal Emergency Management Agency (FEMA).

Reports that the National Gallery has selected a new chief. Director-to-be Earl A. Powell III; Activities of the former director J. Carter Brown; Need for skill in management, public relations and politics; The National Gallery's unparalleled permanent collection.

Presents an interview with outgoing National Endowment for the Arts (NEA) Chairman John Frohnmayer. His personal feelings about the pressure he was under to resign; Defense of his actions while in office; Response to calls to abolish the NEA; Plans for the future.

Discusses how rumors of mob involvement in President John F. Kennedy's death have proved particularly resilient over the years. The House Select Committee on Assassinations (HSCA), and its conclusion; Disclosure of new information by mob lawyer Frank Ragano; Involvement of Teamster head Jimmy Hoffa; The goal of Oliver Stone's `JFK' film. INSET: Suspicious memo to CIA declassified!, by D. Gates..

Reports that scientists are finding ways to identify exactly who is most likely to develop cancer and heart disease. Pioneers in the new field called ecogenetics or molecular epidemiology; Last week's 8th International Congress of Human Genetics; Discovery of two human genes that may explain why only some heavy smokers get lung cancer; Library of 400 genetic mutations caused by carcinogens; The hunt for killer DNA; Exposure to asbestos.

Considers how hospitals are seeking radical solutions to ease walk-in patient overload. Reducing `inappropriate use' or ERs for everything from sunburns to hangnails; Comments by Dr. Robert Derlet, director of the emergency department at the University of California, Davis, Medical Center in Sacramento; Baltimore's Johns Hopkins University Hospital's purchase of its own Urgent Care Clinic in 1985; Moral issues.

Considers alternative medicine that is based on the theory that the body has a natural healing ability. Homeopathic remedies; Dr. Ifeoma Ikenze, a Marin County, Calif. pediatrician who uses homeopathy in her practice; What conventional doctors want; Naturopaths and other practitioners claim to treat the cause of disease, not the symptoms.

Examines how a record number of immigrant children pose new problems for schools. Although immigrant children have had the right to special help in public schools since a 1974 Supreme court decision, schools question how much and what kind of help. Bilingual-education programs; How immigrant parents can be a great resource. INSET: Many-tongued classes..

Examines how President George Bush, unless he breaks with his aides, may botch national energy policy. Compares and contrasts his position to former President Jimmy Carter in the 1970s. Energy-saving devices that didn't exist in the 1970s; Increased environmental concern; Description of the preliminary energy proposals and how environmentalists have criticized it.

Examines how turf wars break out as released mental patients and ex-addicts move into housing for the elderly. Elderly individuals remark on changes in their apartment buildings as the fastest-growing population in their projects is the young disabled. Public-housing officials caught in the middle of the controversy; HUD regulations and limits on screening housing applicants; Success the public-housing agency in St. Paul, Minn. has had in resolving the conflict.

Discusses Operation PUSH, a Chicago-based civil-rights organization, and its boycott of athletic shoemaker Nike because Nike wouldn't reveal certain business and market information. PUSH national director Rev. Tyrone Crider; 21 percent of Nike's employees are minorities; Nike commercials featuring minorities and women; Support of basketball star Michael Jordan; PUSH's association with rival company Reebok; PUSH targets largest company in the market. INSET: A foot race..

Reports on the intermission in the debate over the National Endowment for the Arts (NEA) until September. Description of some amendments to the arts bill; Commission appointed by President Bush to examine the NEA's standards; Opposition to unrestricted arts funding.

Discusses the burgeoning global market for animal parts and that American wildlife is bearing the brunt of the market. Poachers are going after an array of endangered species; Elk antlers in high demand; Caviar from freshwater paddlefish; United States Fish and Wildlife Service (FWS) estimates that trade in illegal animal parts have reached $200 million per year.

Discusses the Superconducting Supercollider (SSC), for which the House of Representatives voted $318 million and will probably pay for the rest of the $8 billion needed to finish it. Quark-barrel politics; SSC accelerates protons to nearly the speed of light and crashes them into one another; Politics of big science.

Talks about cystic fibrosis and the recent announcement by scientists at the University of Michigan and Toronto's Hospital for Sick Children that they've isolated the gene responsible for the disease. Discusses cystic fibrosis, uses of gene marker, and new research.