Developmental expression of heterotrimeric G proteins in the nervous system of Manduca sexta.

The heterotrimeric G proteins are a conserved family of guanyl nucleotide-binding proteins that appear in all eukaryotic cells but whose developmental functions are largely unknown. We have examined the developmental expression of representative G proteins in the developing nervous system of the moth Manduca sexta. Using affinity-purified antisera against different G alpha subunits, we found that each of the G proteins exhibited distinctive patterns of expression within the developing central nervous system (CNS), and that these patterns underwent progressive phases of spatial and temporal regulation that corresponded to specific aspects of neuronal differentiation. Several of the G proteins examined (including Gs alpha and G(o) alpha) were expressed in an apparently ubiquitous manner in all neurons, but other proteins (including Gi alpha) were ultimately confined to a more restricted subset of cells in the mature CNS. Although most of the G proteins examined could be detected within the central ganglia, only G(o) alpha-related proteins were seen in the developing peripheral nerves; manipulations of G protein activity in cultured embryos suggested that this class of G protein may contribute to the regulation of neuronal motility during axonal outgrowth. G(o) alpha-related proteins were also localized to the developing axons and terminals of the developing adult limb during metamorphosis. These intracellular signaling molecules may, therefore, play similar developmental roles in both the embryonic and postembryonic nervous system.

Use of peer role models to increase Pap smear and mammogram screening in Mexican-American and black women.

We evaluated the use of a community-based intervention model to increase Pap smear and mammogram screening in minority women. The community programs were based on the A Su Salud (To Your Health) model, which includes the presentation of positive role models in the media and positive social reinforcement by community volunteers. Mexican-American women 40-70 years of age in Corpus Christi, Texas, and black women 40-70 years of age in Galveston, Texas, were targeted. Role models from the target community told their personal stories about cancer screening through local media (television, radio, and newspapers). Volunteers reinforced media messages among the target audience by distributing newsletters. Preintervention and postintervention cross-sectional surveys among the target group measured relative increases in knowledge, attitude, and practice. Pap smear use (past two years) was not substantially improved. Mammogram use (past two years) increased 57% among Mexican-American women (prevalence rate ratio [PRR] = 1.57; 90% confidence interval [CI] = 1.19, 2.08) and 30% among black women (PRR = 1.30; 90% CI = 1.04, 1.63). We demonstrated the feasibility of implementing a peer role model intervention at the local health department level. The improvement in mammogram use among high-risk women is encouraging, but further controlled research is needed to test the effectiveness and cost-efficiency of this approach.

Local health departments implement a theory-based model to increase breast and cervical cancer screening.

Su Vida, Su Salud/Your Life, Your Health is a community program to increase participation in breast and cervical cancer screening. This program illustrates the diffusion of an innovative outreach strategy from a research environment to two local health departments. The program uses A Su Salud, the communication model in which positive role models are featured in the media, and community volunteers who give positive social reinforcement. Local health departments in Galveston and Corpus Christi, TX, were selected to implement the model because of excessive mortality rates in the region and the departments' adequate level of resources and commitment. Over an 18-month period, 54 stories of role models appeared in the media in Corpus Christi, and 60 appeared in Galveston. There were 490 volunteers active in Corpus Christi and 279 in Galveston. Of 365 inquiries to the Corpus Christi program, 35 percent were from the Mexican American target group of women ages 40-70. Of 1,457 women who contacted the Galveston program, 9 percent were from the African American target group ages 40-70. Local health departments are well-suited to participation in cancer control research applications because they have direct access to high-risk populations and have the authority to institutionalize effective interventions.

Photoaffinity reagents for use with pepsin and other carboxyl proteases.

Two compounds have been designed to serve as photoaffinity reagents for use with carboxyl proteases. 1,2-Epoxy-3-(4'-azido-2'-nitrophenoxy)propane has been synthesized and shown to react with porcine pepsin in the same fashion as the traditional inhibitor 1,2-epoxy-3-(p-nitrophenoxy)propane, while p-azidophenacyl bromide is similar to other phenacyl bromides in its reaction with pepsin. In combination with p-azido-alpha-diazoacetophenone, previously shown to resemble alpha-diazo carbonyl reagents in its reaction with pepsin, photoaffinity analogs are now available for all three of the widely-used carboxyl protease inhibitors.