No abstract

In the limb bud of the 5-day-old avian embryo, when primary muscle fibre formation is beginning and before specific muscles appear, differences in the expression of fast and slow myosin heavy chain genes can be detected among primary fibres of the premuscle masses. Myoblasts that form colonies of fibres of specific types can be isolated from these limb buds. To assess the role of myoblast commitment in specifying fibre types during embryonic development, we cloned myoblasts of specific types from embryonic and adult muscles, transfected them with a reporter gene, and transferred them into developing limb buds. After transfer, cloned myoblasts formed fibres in the limb with the same patterns of myosin heavy chain gene expression as the fibres they formed in cell culture. These results demonstrate that initial skeletal muscle fibre type diversity during avian limb development can originate, in part, from the commitment of distinct myoblast types to the formation of specific fibre types.

Chronic hepatitis B is the leading cause of liver cancer and the largest health disparity between Asian/Pacific Islanders (APIs) and the general US population. The Hep B Free model was launched to eliminate hepatitis B infection by increasing hepatitis B awareness, testing, vaccination, and treatment among APIs by building a broad, community-wide coalition. The San Francisco Hep B Free campaign is a diverse public/private collaboration unifying the API community, health care system, policy makers, businesses, and the general public in San Francisco, California. Mass-media and grassroots messaging raised citywide awareness of hepatitis B and promoted use of the existing health care system for hepatitis B screening and follow-up. Coalition partners reported semi-annually on activities, resources utilized, and system changes instituted. From 2007 to 2009, over 150 organizations contributed approximately $1,000,000 in resources to the San Francisco Hep B Free campaign. 40 educational events reached 1,100 healthcare providers, and 50% of primary care physicians pledged to screen APIs routinely for hepatitis B. Community events and fairs reached over 200,000 members of the general public. Of 3,315 API clients tested at stand-alone screening sites created by the campaign, 6.5% were found to be chronically infected and referred to follow-up care. A grassroots coalition that develops strong partnerships with diverse organizations can use existing resources to successfully increase public and healthcare provider awareness about hepatitis B among APIs, promote routine hepatitis B testing and vaccination as part of standard primary care, and ensure access to treatment for chronically infected individuals.

Background: Previous smallpox ring vaccination models based on contact tracing over a network suggest that ring vaccination would be effective, but have not explicitly included response logistics and limited numbers of vaccinators.

The highest users of repeat testing are those who are practicing the highest risk behaviors and have the highest incidence of HIV. This suggests that prevention messages should be modified to more explicitly address the behaviors that are putting individuals at high risk for HIV.