Reported changes in sexual behavior in response to AIDS in the United States.

BACKGROUND: The AIDS epidemic has profoundly affected public health policy and everyday choices of individuals. Understanding the self-protective strategies adopted by the general population is crucial to designing appropriate and more effective primary AIDS prevention strategies. METHODS: A probability sample of the U.S. adult population in 1992, the National Health and Social Life Survey (n = 3,159), addressed detailed aspects of sexual behavior. How respondents changed their sexual behavior due to AIDS was recorded verbatim and categorized for analysis. RESULTS: Twenty-nine percent of U.S. adults reported some sexual behavior change, primarily, reducing numbers of partners (12%), using condoms more frequently (9%), selecting partners more carefully (7%), changing attitude toward sex (4%), and abstinence (3%). Individuals most at risk show the greatest propensity to change although the actual risk-reduction strategies and the meanings assigned to those strategies vary considerably. Strategies are not all compatible with each other nor equally likely to be adopted by individuals with different lifestyles. CONCLUSIONS: Self-protective strategies to avoid AIDS are widespread, but primary prevention efforts should be targeted to particular circumstances and the self-protective propensities of each individual.

Private sexual behavior, public opinion, and public health policy related to sexually transmitted diseases: a US-British comparison.

OBJECTIVES: The purpose of this study was to characterize sexual behavior and opinions about sex in the United States and Britain; implications are discussed for effective public health policy regarding sexually transmitted diseases (STDs) in the United States. METHODS: Large-scale national probability surveys conducted in the 2 countries detailed sexual behavior, opinions, and the prevalence of STDs. RESULTS: In comparison with that of Britain, the US population has greater variability in sexual behavior, less tolerant opinions about sexual behavior, and a higher STD prevalence and lower condom usage among men. CONCLUSIONS: The survey data show compelling evidence from both countries of a strong association between number of sex partners and STD risk. In the United States relative to Britain, there is both greater dispersion in sexual behavior and a greater incidence of unconditional opposition to certain sexual practices. The former implies a need for strong public health policy to address the risks of STDs, but the latter implies strong opposition to that policy. This disjuncture between public health need and feasibility may contribute to the high US rate of STDs.

CDO: an oncogene-, serum-, and anchorage-regulated member of the Ig/fibronectin type III repeat family.

Cell adhesion molecules of the Ig superfamily are implicated in a wide variety of biological processes, including cell migration, axon guidance and fasciculation, and growth control and tumorigenesis. Expression of these proteins can be highly dynamic and cell type specific, but little is known of the signals that regulate such specificity. Reported here is the molecular cloning and characterization of rat CDO, a novel cell surface glycoprotein of the Ig superfamily that contains five Ig-like repeats, followed by three fibronectin type III-like repeats in its extracellular region, and a 256-amino acid intracellular region that does not resemble other known proteins. In rat embryo fibroblasts, cdo mRNA expression is maximal in confluent, quiescent cells. It is rapidly and transiently down-regulated by serum stimulation of such cells, and is constitutively down-regulated in oncogene-transformed derivatives of these cells. CDO protein levels are also dramatically regulated by cell-substratum adhesion, via a mechanism that is independent of cdo mRNA expression. The amount of CDO produced at the surface of a cell may therefore be governed by a complex balance of signals, including mitogenic stimuli that regulate cdo mRNA levels, and substratum-derived signals that regulate CDO protein production. cdo mRNA is expressed at low levels in most adult rat tissues. A closely related human gene maps to chromosome 11q23-24, a region that displays frequent loss of heterozygosity in human lung, breast, and ovarian tumors. Taken together, these data suggest that loss of CDO function could play a role in oncogenesis.

Dissociation of ras oncogene-induced gene expression and anchorage-independent growth in a series of somatic cell mutants.

The mechanism or mechanisms by which ras oncogenes induce morphological transformation and anchorage-independent growth are poorly understood but are thought to involve stable alterations in gene expression. We previously described a genetically dominant, mutant rat fibroblast cell line (ER-1-2) that is resistant to ras-induced anchorage-independent growth. We now describe a cell line derived from ER-1-2 cells, termed ER-1-2T, that has apparently sustained a second, dominant mutation that conferred on these cells the ability to form colonies in soft agar. Analysis of these and control cell lines demonstrated that deregulation of many of the genes commonly associated with the transformed phenotype could be dissociated from anchorage-independent growth. After infection with a ras-expressing retrovirus, both control and ER-1-2 cell lines constitutively expressed elevated levels of the c-jun, junB, fosB, c-myc, collagenase, ornithine decarboxylase, osteopontin, stromelysin, cathepsin L, and insulin-like growth factor 1 genes. These data indicate that signaling events downstream of ras were largely intact in ER-1-2 cells and that the defect in these cells lies either on a pathway separate from those that control stable, ras-mediated expression of these genes or at a point in the cell-division cycle distinct from those that control expression of the genes. In contrast, only c-jun, junB, c-myc, and ornithine decarboxylase were expressed at a significantly elevated level in ER-1-2T cells. Thus, deregulated expression of the genes analyzed was not sufficient for anchorage-independent growth. Furthermore, deregulation of most of them was also not necessary.

Reusable optical image storage and processing device.

The PROM (Pockels Readout Optical Modulator) described in this paper is a device for storing and processing optical images and information in recyclable, real time operating systems. The device consists of a single active layer of a cubic photosensitive, electrooptic material. ZnS, ZnSe, and Bi(12)SiO(20) devices have been fabricated and characterized demonstrating high writein sensitivity, high resolution, high contrast, high optical and diffraction efficiency, fast recycling times, long storage times, and freedom from fatigue. Operating modes and measured performance parameters are discussed.