The Physical Activity Daily (PAD) Trial: The rationale and design of a randomized controlled trial evaluating an internet walking program to improve maximal walking distance among patients with peripheral arterial disease.

BACKGROUND: Despite established guidelines for regular walking as a first line therapy for adults with peripheral arterial disease (PAD), most patients do not walk routinely. This paper presents the design specifications for a randomized clinical trial to examine the effectiveness of an internet-based walking program compared to a telephone intervention, or the combination (internet-based with telephone counseling) for promotion of regular walking in patients with PAD. METHODS: Sedentary adults with documented lower extremity PAD are being recruited from the University of Michigan Health System and the surrounding area. Participants are randomized to one of four arms in a 2×2 factorial design: 1) telephone counseling to promote walking, 2) an internet-based walking program with tailored step-count goals, 3) the combination of telephone counseling with the internet-based walking program, or 4) waitlist control. Participants receive a 4-month intervention phase, after which all participants are followed for an additional 8months to assess long-term adherence to regular walking. Outcomes are assessed at baseline, 4 and 12months. The primary outcome is walking distance assessed through a standardized treadmill protocol. Additional outcomes include change in step-counts measured with a commercial activity tracker, pain-free walking distance, and changes in health-related quality of life from baseline to follow-up. CONCLUSION: Finding effective and feasible programs to promote walking among PAD patients is warranted. This study will add to current evidence regarding use of internet based programs with and without telephone counseling to promote regular walking in this population.

Reactive Oxygen Stimulation of Interleukin-6 Release in the Human Trophoblast Cell Line HTR-8/SVneo by the Trichlorethylene Metabolite S-(1,2-Dichloro)-l-Cysteine.

Trichloroethylene (TCE) is a common environmental pollutant associated with adverse reproductive outcomes in humans. TCE intoxication occurs primarily through its biotransformation to bioactive metabolites, including S-(1,2-dichlorovinyl)-l-cysteine (DCVC). TCE induces oxidative stress and inflammation in the liver and kidney. Although the placenta is capable of xenobiotic metabolism and oxidative stress and inflammation in placenta have been associated with adverse pregnancy outcomes, TCE toxicity in the placenta remains poorly understood. We determined the effects of DCVC by using the human extravillous trophoblast cell line HTR-8/SVneo. Exposure to 10 and 20 µM DCVC for 10 h increased reactive oxygen species (ROS) as measured by carboxydichlorofluorescein fluorescence. Moreover, 10 and 20 µM DCVC increased mRNA expression and release of interleukin-6 (IL-6) after 24-h exposure, and these responses were inhibited by the cysteine conjugate beta-lyase inhibitor aminooxyacetic acid and by treatments with antioxidants (alpha-tocopherol and deferoxamine), suggesting that DCVC-stimulated IL-6 release in HTR-8/SVneo cells is dependent on beta-lyase metabolic activation and increased generation of ROS. HTR-8/SVneo cells exhibited decreased mitochondrial membrane potential at 5, 10, and 20 µM DCVC at 5, 10, and 24 h, showing that DCVC induces mitochondrial dysfunction in HTR-8/Svneo cells. The present study demonstrates that DCVC stimulated ROS generation in the human placental cell line HTR-8/SVneo and provides new evidence of mechanistic linkage between DCVC-stimulated ROS and increase in proinflammatory cytokine IL-6. Because abnormal activation of cytokines can disrupt trophoblast functions necessary for placental development and successful pregnancy, follow-up investigations relating these findings to physiologic outcomes are warranted.

Supraglottic airway devices.

Supraglottic airway devices (SADs) are used to keep the upper airway open to provide unobstructed ventilation. Early (first-generation) SADs rapidly replaced endotracheal intubation and face masks in > 40% of general anesthesia cases due to their versatility and ease of use. Second-generation devices have further improved efficacy and utility by incorporating design changes. Individual second-generation SADs have allowed more dependable positive-pressure ventilation, are made of disposable materials, have integrated bite blocks, are better able to act as conduits for tracheal tube placement, and have reduced risk of pulmonary aspiration of gastric contents. SADs now provide successful rescue ventilation in > 90% of patients in whom mask ventilation or tracheal intubation is found to be impossible. However, some concerns with these devices remain, including failing to adequately ventilate, causing airway damage, and increasing the likelihood of pulmonary aspiration of gastric contents. Careful patient selection and excellent technical skills are necessary for successful use of these devices.