DNA polyplexes formed using PEGylated biodegradable hyperbranched polymers.

A novel PEGylated biodegradable hyperbranched PEG-b-PDMAEMA has been synthesized. The low toxicity, small molecular weight PDMAEMA chains were crosslinked using a biodegradable disulfide-based dimethacrylate (DSDMA) agent to yield higher molecular weight hyperbranched polymers. PEG chains were linked onto the polymer surface, masking the positive charge (as shown by Zeta potential measurements) and reducing the toxicity of the polymer.

Access to primary care for Medicare beneficiaries.

Objectives: To determine the acceptance rate of new Medicare patients by all primary care physicians. Among primary care physicians accepting new patients, to determine whether demographic and geographic factors are associated with the likelihood of accepting new Medicare patients.

Design: Cross-sectional.

Perceptions of physicians on the barriers and facilitators to integrating fall risk evaluation and management into practice.

Background: Falls are common, treatable, and result in considerable morbidity in older adults. However, fall risk factor evaluation and management targeted at high-risk patients is largely neglected in clinical practice.

Objective: To identify barriers and facilitators to the implementation of fall risk management by primary care providers.