Increased Time Difference between Imagined and Physical Walking in Older Adults at a High Risk of Falling.

Walking motor imagery ability is thought to be associated with a fear of falling; however, no studies have compared fall risk and motor imagery ability. This study aimed to ascertain the time difference between imagined and physical walking in older adults at low and high risks of falling. Motor imagery ability was assessed using mental chronometry, which measures the imagined time required for movement. Participants included 31 older adults classified as having a high (n = 15) or low (n = 16) risk of falling based on single leg stance time. The time required for imagined and physical walking was measured using 5 m long walkways with three different widths (15, 25, and 50 cm), and the temporal errors (absolute and constant error) were compared. Physical walking time was significantly longer in the high-risk group than in the low-risk group for the 15 and 25 cm wide walkways. The absolute error between the imagined and physical walking times was significantly larger in the high-risk group than in the low-risk group for the 15 and 25 cm wide walkways. There was also a significant difference in the constant error between the high- and low-risk groups between the imagined and physical walking times for all three walkways. Older adults who may be at a higher risk of falling showed longer walking times during action execution but overestimated their performance (i.e., they believe they would be faster) during motor imagery. Therefore, the time difference between imagined and physical walking could, in part, be useful as a tool for assessing fall risk based on motor imagery.

Lectin Isolated from Japanese Red Sword Beans (Canavalia gladiata) as a Potential Cancer Chemopreventive Agent.

In this study, we investigated the chemical and biological profile of lectin isolated from Japanese red sword beans (Canavalia gladiata; RSBs). RSB lectin was purified using maltamyl-Sepharose 4B and subjected to amino acid composition and partial amino acid sequencing analyses, and evaluated for blood and carbohydrate specificity, mitogenic activity, splenic natural killer (NK) cell activity, and its effect on B16 melanoma cell proliferation, compared with Concanavalin A (Con A). The amino acid composition and sequences of RSB lectin were similar to those of Con A. RSB lectin showed specificity to mannose, glucose, maltose, methyl-D-mannoside, and thyroglobulin, but not rhamnose, using mouse, sheep, and rabbit erythrocytes. Compared with Con A, RSB lectin showed low resistance to proteases and to temperatures greater than 70 °C, but high mitogenic activity for mouse splenic cells. Notably, while treatment with RSB lectin and Con A (0.01 and 0.1 µg/mL) promoted similar levels of splenic NK cell activity, which were higher than that observed in the control (0 µg/mL) and interleukin 2 (IL-2) (25 U)-treated populations, RBS lectin exerted a significantly stronger anti-proliferative effect than Con A at a concentration of 125.0 µg per well. Overall, our results show that RSB lectin might exert immunological effects on mouse splenic cells and could thus be used as a potential cancer chemopreventive agent. PRACTICAL APPLICATION: Japanese red sword bean (RSB) is a tropical perennial legume consumed in many Asian countries. RSB lectin shows specificity to mannose, glucose, maltose, methyl-d-mannoside, and thyroglobulin, but not to rhamnose, using mouse, sheep, and rabbit erythrocytes. RSB lectin exhibits similarities to Concanavalin A in amino acid composition and sequence, shows mitogenic activity for mouse splenic cells and strong anti-proliferative activity for B16 melanoma cells, and also enhances the activity of splenic natural killer (NK) cells against YAC-1 cells. Thus, RSB lectin has the potential to be used as a bioactive protein in medical research.

Electrical stimulation ventilatory feedback facilitates maintenance of a prolonged expiration pattern during exercise: A proof-of-concept study in healthy adults.

This study aimed at verifying the safety and effects of electrical stimulation ventilatory feedback (ESVF) to provide feedback during expiration, which may assist with breathing control in patients with chronic obstructive pulmonary disease (COPD). Because this is a new therapy, we examined the feasibility of the therapy in healthy adults. The 23 healthy adult participants were randomized into two groups: a stimulation group that received ESVF and a placebo group with the ESVF device attached, but not activated. Sensory stimulation was provided at a frequency of 20 Hz and pulse duration of 200 µs. During breathing training, participants practiced a prolonged expiration pattern and were instructed to maintain the breathing pattern during exercise. A variety of parameters such as respiratory time from the gas analyzer monitor and quantitative load were measured during lower-extremity cycle ergometer exercise. The primary outcome was the expiratory to inspiratory time ratio, which was significantly higher in the stimulation group than in the placebo group, both during and after exercise. No side effects were reported during the use of electrical stimulation. Therefore, ESVF is safe and facilitates maintenance of a prolonged expiration pattern during and after exercise.