Potent inhibition of respiratory syncytial virus by polyoxometalates of several structural classes.

A series of polyoxometalates (POM) were synthesized and evaluated for anti-respiratory syncytial virus (RSV) activity. POM containing zirconium, tungsten, silicon, platinum, niobium or germanium of a variety of structural types have been evaluated. Sixteen of the compounds had very striking anti-RSV activity against a clinical isolate, Utah 89, with median effective concentration (EC50) values < or = 3 microM and selective indices > 80 as determined by viral cytopathic inhibition effect, neutral red uptake and virus yield reduction assays. The EC50 values for all three assays correlated very well (Pearson correlation coefficients > 0.90). POM containing sodium cations were totally inactive. Germanium-, niobium-, tin- and zirconium-containing compounds were found to be highly potent and selective. The antiviral activity was not cell line-dependent. The median cytotoxic concentration (IC50) values were generally greater than 100 microM. The compounds were also comparably active against a known laboratory RSV strain, A2, as well as other RSV strains. To detect any virus strain-specific inhibitory activity, seven POM were tested against other RSV strains; all were nearly equally inhibitory to the human virus strains, suggesting no strain specificity. Timing studies suggested that these compounds were most inhibitory during virus adsorption and penetration, although RSV was still significantly inhibited when the compound was added 3 h post-infection; which is considered well into the eclipse period. These data suggest that these potent, non-toxic compounds should be further studied as potential chemotherapeutic agents for treating RSV infections.

An overhead harness and trolly system for balance and ambulation assessment and training.

Safe assessment of standing balance and gait is often jeopardized by the potential for falls, which may have major physical and legal consequences. This article describes the design and use of a system that enhances the safety of the patient and clinician during balance and gait assessment and training. The system consists of an overhead track and moveable trolly that allows the patient, while secured in a simple body harness, the freedom to ambulate, perform functional types of activities, and fall with minimal risk of injury. As a result, a single therapist can more readily assess balance and ambulation, as well as provide training for these skills. In addition, the therapist is free to observe the patient's movements from any position, without direct physical contact. Practically, the system described may allow ambulation training sooner after injury or surgery, permit training in weight-bearing or partial weight-bearing activities with or without assistive devices, and allow the clinician to focus on assessment and training, rather than on patient safety.

Field testing as clinical trial methodology in periodontics.

In the early 1950s the randomized control trial (RCT) was introduced and became widely accepted as the definitive proof of efficacy of a specific medical treatment. In fact, the acceptance and application of this methodology were instrumental in converting medicine from an unpredictable art to a science. At present no other methodologies exist that allow the evaluation of therapeutic efficacy with confidence comparable to that achieved with randomized controlled trials. In recent years researchers have applied new experimental designs and data analysis techniques to clinical trials conducted in a field trial environment to facilitate the understanding of proper use of new therapeutic agents and procedures. Since many of the new methodologies are still evolving or have only recently been introduced, this review considers some of the major trends and developments, as well as experiences of the authors, in field trial methodology. This manuscript addresses the following questions: 1) are there current clinical trial needs that are not met by RCT? 2) If so, what considerations are necessary for new approaches to have scientific usefulness? and 3) What are the strengths and weaknesses of the field trial's setting relative to an institutional environment?