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N euromuscular electrical stimulation (NMES) is a promising tool in the rehabilitation of individuals with a limited ability to activate their skeletal muscles, 13,35,36 as well as a method of strength training and short-term resistance training in athletic populations. 26,27 During NMES application, the capacity to maintain performance is compromised compared to voluntary exercise, Experimental laboratory study.The primary purpose was to investigate the independent effects of current amplitude, pulse duration, and current frequency on muscle fatigue during neuromuscular electrical stimulation (NMES). A second purpose was to determine if the ratio of the evoked torque to the activated area could explain muscle fatigue.Parameters of NMES have been shown to differently affect the evoked torque and the activated area. The efficacy of NMES is limited by the rapid onset of muscle fatigue.Seven healthy participants underwent 4 NMES protocols that were randomly applied to the knee extensor muscle group. The NMES protocols were as follows: standard protocol (Std), defined as 100-Hz, 450-μs pulses and amplitude set to evoke 75% of maximal voluntary isometric torque (MVIT); short pulse duration protocol (SP), defined as 100-Hz, 150-μs pulses and amplitude set to evoke 75% of MVIT; low-frequency protocol (LF), defined as 25-Hz, 450-μs pulses and amplitude set to evoke 75% of MVIT; and low-amplitude protocol (LA), defined as 100-Hz, 450-μs pulses and amplitude set to evoke 45% of MVIT. The peak torque was measured at the start and at the end of the 4 protocols, and percent fatigue was calculated. The outcomes of the 4 NMES protocols on the initial peak torque and activated cross-sectional area were recalculated from a companion study to measure torque per active area.Decreasing frequency from 100 to 25 Hz decreased fatigue from 76% to 39%. Decreasing the amplitude and pulse duration resulted in no change of muscle fatigue. Torque per active area accounted for 57% of the variability in percent fatigue between Std and LF protocols.Altering the amplitude of the current and pulse duration does not appear to influence the percent fatigue in NMES. Lowering the stimulation frequency results in less fatigue, by possibly reducing the evoked torque relative to the activated muscle area.

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PURPOSE A phase I dose escalation study was performed with systemically delivered lyso-thermosensitive liposomal doxorubicin (LTLD) (Celsion Corp., Columbia, MD). The primary objectives were to determine the safe maximum tolerated dose (MTD), pharmacokinetic (PK) properties, and dose limiting toxicity (DLT) of LTLD during this combination therapy. MATERIALS AND METHODS Subjects eligible for percutaneous or surgical RFA with primary (n=9) or metastatic (n=15) tumors of the liver, with lesions 4 or less in number and up to 7 cm in diameter were included. RFA was initiated 15 minutes after starting a 30 minute intravenous LTLD infusion. Dose levels between 20 and 60 mg/m2 were evaluated. MRI, PET and CT scans were performed at predetermined intervals pre and post-treatment until evidence of recurrence, administration of additional antitumor treatment, or a total of 3 years. RESULTS DLT criteria were met at 60 mg/m2, and the MTD was defined as 50 mg/m2. RFA was performed during the peak of the plasma concentration-time curve, in an effort to yield maximal drug deposition. LTLD produced reversible, dose-dependent neutropenia and leukopenia. CONCLUSION LTLD can be safely administered systemically at the MTD (50 mg/m2) in combination with RFA, with limited and manageable toxicity. Further evaluation of this agent combined with RFA is warranted to determine its role in the management of liver tumors.

Study design: Longitudinal. Objectives: The purpose of this study was to evaluate the effect of lower extremity resistance training on quadriceps fatigability, femoral artery diameter, and femoral artery blood flow. Setting: Academic Institution. Methods: Five male chronic spinal cord injury (SCI) individuals (American Spinal Injury Association (ASIA): A complete; C5-T10; 3675 years old) completed 18 weeks of home-based neuromuscular electrical stimulation (NMES) resistance training. Subjects trained the quadriceps muscle group twice a week with four sets of 10 dynamic knee extensions against resistance while in a seated position. All measurements were made before training and after 8, 12, and 18 weeks of training. Ultrasound was used to measure femoral artery diameter and blood flow. Blood flow was measured before and after 5 and 10 min of distal cuff occlusion, and during a 4-min isometric electrical stimulation fatigue protocol. Results: Training resulted in significant increases in weight lifted and muscle mass, as well as a 60% reduction in muscle fatigue (P ¼ 0.001). However, femoral arterial diameter did not increase. The range was 0.4470.03 to 0.4670.05 cm over the four time points (P ¼ 0.70). Resting, reactive hyperemic, and exercise blood flow did not appear to change with training. Conclusion: NMES resistance training improved muscle size and fatigue despite an absence of response in the supplying vasculature. These results suggest that the decreases in arterial caliber and blood flow seen with SCI are not tightly linked to muscle mass and fatigue resistance. In addition, muscle fatigue in SCI patients can be improved without increases in arterial diameter or blood flow capacity.