When You Can't Walk a Mile: Walking Limitation Prevalence and Associations Among Middle-Aged and Older US Adults with Arthritis: A Cross-Sectional, Population-Based Study.

OBJECTIVE: We examined walking limitations and associated characteristics among middle-aged and older US adults with arthritis, overall, and by sex. METHODS: Using 2005-2006 Arthritis Conditions and Health Effects Survey (ACHES) data (n = 1793), we estimated "a lot" and "any" ("a lot" or "a little" combined) walking limitation for more than 1 mile (1.6 km) among US adults 45 years or older with arthritis and examined associations (sociodemographics, arthritis symptoms and effects, psychosocial measures, and physical health) with walking limitations in unadjusted and multivariable (MV) adjusted logistic regression models using prevalence ratios (PRs) and 95% confidence intervals, accounting for the complex survey design. RESULTS: Respondents frequently reported "a lot" (48%) and "any" (72%) limitation for more than 1 mile. Women reported higher prevalence of all levels of walking limitation versus men (eg, 51% vs 42% for "a lot" overall); additionally, the gap for walking limitations between women and men widened with age. Limitation was high for both sexes at all ages, affecting 1-in-3 to 4-in-5, depending on level of walking limitation. The strongest MV associations for "a lot" of walking limitation among all respondents included substantial and modest arthritis-attributable life interference (PR = 2.5 and 1.6, respectively), age 75 years or older (PR = 1.5), and physical inactivity and fair/poor self-rated health (PR = 1.4 for both). CONCLUSION: Walking limitations among middle-aged and older adults are substantial. Existing proven interventions that improve walking ability and physical function may help this population to reduce and delay disability.

Continuum Electrostatics Approaches to Calculating pKas and Ems in Proteins.

Proteins change their charge state through protonation and redox reactions as well as through binding charged ligands. The free energy of these reactions is dominated by solvation and electrostatic energies and modulated by protein conformational relaxation in response to the ionization state changes. Although computational methods for calculating these interactions can provide very powerful tools for predicting protein charge states, they include several critical approximations of which users should be aware. This chapter discusses the strengths, weaknesses, and approximations of popular computational methods for predicting charge states and understanding the underlying electrostatic interactions. The goal of this chapter is to inform users about applications and potential caveats of these methods as well as outline directions for future theoretical and computational research.

CONSTRUCTING SURROGATE MODELS OF COMPLEX SYSTEMS WITH ENHANCED SPARSITY: QUANTIFYING THE INFLUENCE OF CONFORMATIONAL UNCERTAINTY IN BIOMOLECULAR SOLVATION.

Biomolecules exhibit conformational fluctuations near equilibrium states, inducing uncertainty in various biological properties in a dynamic way. We have developed a general method to quantify the uncertainty of target properties induced by conformational fluctuations. Using a generalized polynomial chaos (gPC) expansion, we construct a surrogate model of the target property with respect to varying conformational states. To alleviate the high-dimensionality of the corresponding stochastic space, we propose a method to increase the sparsity of the gPC expansion by defining a set of conformational "active space" random variables. With the increased sparsity, we employ the compressive sensing method to accurately construct the surrogate model. We demonstrate the performance of the surrogate model by evaluating fluctuation-induced uncertainty in solvent-accessible surface area for the bovine trypsin inhibitor protein system and show that the new approach offers more accurate statistical information than standard Monte Carlo approaches. Furthermore, the constructed surrogate model also enables us to directly evaluate the target property under various conformational states, yielding a more accurate response surface than standard sparse grid collocation methods. In particular, the new method provides higher accuracy in high-dimensional systems, such as biomolecules, where sparse grid performance is limited by the accuracy of the computed quantity of interest. Our new framework is generalizable and can be used to investigate the uncertainty of a wide variety of target properties in biomolecular systems.

Oncology workforce issues: the challenge of the outpatient clinic.

It is well-recognized that cancer prevalence is increasing and will continue to do so over the coming years. Adaptation of cancer services to this reality, however, has been slow. The oncology workforce, already short-staffed, will be overburdened if change does not occur in a timely manner. The results of this study seek to highlight the current workings of oncology outpatient clinics at this hospital, and to identify areas of deficiencies that need to be addressed. By presenting a portrait of our outpatient clinics, it is hoped that a discussion surrounding workforce issues can be actively engaged, as this is crucial in order to succeed in providing quality care for our cancer patients, and simultaneously to support and mentor our invaluable medical and allied health staff.

SPrCY: comparison of structural predictions in the Saccharomyces cerevisiae genome.

SUMMARY: SPrCY is a web-accessible database which provides comparison of structure prediction results for the Saccharomyces cerevisiae genome. This web service offers the ability to search, analyze and compare the yeast structural predictions from sequence-only (Superfamily, PDBAA BLAST and Pfam) and sequence-structure-based (SAM-T02, 3D-PSSM, mGenTHREADER) methods. AVAILABILITY: The service is freely available via web at http://agave.wustl.edu/yeast/

The effectiveness of physical, psychological, and functional interventions in treating clients with multiple sclerosis: a meta-analysis.

This article provides a meta-analysis of the current best evidence for the use of occupational therapy with clients with multiple sclerosis (MS). A review of the literature identified 23 articles that examined the effectiveness of occupational therapy-related treatments on clients with MS. Meta-analytic analysis suggests that occupational therapy-related treatments were effective in treating the deficits associated with MS (r = .52), particularly for outcomes in the capacity and ability (r = .52; e.g., muscle strength, range of motion, mood) and task and activity (r = .57; e.g., dressing, bathing, ambulation) levels. A review of the research designs used to study MS suggests that more rigorous research is necessary to fully understand treatment effectiveness. Further, more research must be done to establish the effectiveness of occupational therapy treatment at the life role level.

Electrostatics of nanosystems: application to microtubules and the ribosome.

Evaluation of the electrostatic properties of biomolecules has become a standard practice in molecular biophysics. Foremost among the models used to elucidate the electrostatic potential is the Poisson-Boltzmann equation; however, existing methods for solving this equation have limited the scope of accurate electrostatic calculations to relatively small biomolecular systems. Here we present the application of numerical methods to enable the trivially parallel solution of the Poisson-Boltzmann equation for supramolecular structures that are orders of magnitude larger in size. As a demonstration of this methodology, electrostatic potentials have been calculated for large microtubule and ribosome structures. The results point to the likely role of electrostatics in a variety of activities of these structures.

Dynamical properties of fasciculin-2.

Fasciculin-2 (FAS2) is a potent protein inhibitor of the hydrolytic enzyme acetylcholinesterase. A 2-ns isobaric-isothermal ensemble molecular dynamics simulation of this toxin was performed to examine the dynamic structural properties which may play a role in this inhibition. Conformational fluctuations of the FAS2 protein were examined by a variety of techniques to identify flexible residues and determine their characteristic motion. The tips of the toxin "finger" loops and the turn connecting loops I and II were found to fluctuate, while the rest of the protein remained fairly rigid throughout the simulation. Finally, the structural fluctuations were compared to NMR data of fluctuations on a similar timescale in a related three-finger toxin. The molecular dynamics results were in good qualitative agreement with the experimental measurements. Proteins 1999;36:447-453.

The effectiveness of feedback in improving safe behaviors: a review of the literature.

Reducing unsafe behaviors in the work place is of primary concern in industry. Unsafe behaviors seem to be shaped both by a subtle reinforcement of these behaviors by the work culture and by management's failure to define what constitutes unsafe behavior. Thus, any program to change these behaviors must focus both on defining and reinforcing safe behaviors. This paper reviews some of the literature associated with feedback and its effectiveness in increasing worker safety. The Theory of Planned Behavior is discussed as one possible mechanism for explaining the positive results achieved.

Principles for the release of physician-specific health care data: balancing the interests of patients and physicians.

Many state health departments and other agencies have become involved in the collection and analysis of physician-specific health care data. Two states--New York and Pennsylvania--have released surgeon-specific data on the results of coronary artery bypass graft surgery, and the Health Care Financing Administration is considering the release of physician-specific health care data. This article discusses those developments and presents suggested guidelines for the collection, use, and release of physician-specific data.

PRO update. Transition from the third to fourth scope of work.

The Health Care Financing Administration (HCFA) began implementation of the transition from the Third Peer Review Organization (PRO) Scope of Work to the Fourth PRO Scope of Work on October 1, 1991. PROs in 11 states are currently implementing newly-established medical review requirements under the "Scope of Work," the contract by which PROs are obligated to carry out their statutorily-mandated duties of determining the medical necessity, appropriateness and quality of care delivered to Medicare beneficiaries. Michigan's PRO (MPRO) is scheduled to implement requirements outlined in the Fourth Scope of Work beginning April 1, 1992. This article discusses the American Medical Association's (AMA) relationship to the PRO program and the transition from the Third to the Fourth Scope of Work including the status of the Uniform Clinical Data Set.

The Fourth PRO Scope of Work: automating the medical review process through the Uniform Clinical Data Set.

With the advent of the Fourth Scope of Work, peer review organizations are beginning to implement the Uniform Clinical Data Set, an automated medical review system designed to collect standardized data from Medicare medical records and provide a data base to determine the most effective treatment for a given illness or disease. In this article, the author discusses the Health Care Financing Administration's development of the Uniform Clinical Data Set and its proposed application within the context of the Health Care Quality Improvement Initiative and the Fourth Scope of Work.