Feasibility of intensive mobility training to improve gait, balance, and mobility in persons with chronic neurological conditions: a case series.

BACKGROUND AND PURPOSE: Intensive mobility training (IMT) is a rehabilitative approach aimed at improving gait, balance, and mobility through the incorporation of task-specific, massed practice. The purpose of this case series was to examine the feasibility and benefits of the IMT protocol across a sample of 4 individuals with diverse chronic neurological diagnoses, including incomplete spinal cord injury, Parkinson's disease, stroke, and cerebral hemispherectomy. METHODS: The 4 participants enrolled in the IMT protocol and followed an intensive treatment schedule of 3 h/d sessions for 10 consecutive weekdays totaling 30 hours. Each session allocated 1 hour each to (1) body weight-supported treadmill-based locomotor training, (2) balance interventions, and (3) activities to improve coordination, strength, and range of motion. Interventions emphasized repetitive, task-specific training of lower-extremity movements in a massed practice schedule. Pain, fatigue, and time in activity were used to assess feasibility of the treatment. Temporal-spatial gait parameters, Berg Balance Scale, Dynamic Gait Index, Timed Up and Go test, and 6-Minute Walk test were used to assess changes in performance. RESULTS: Participants were able to complete an average of 144 of 180 minutes of activity per day for 10 days. Participants demonstrated modest improvements after the intervention on at least one outcome measure for each target area of gait, mobility, and balance. Some improvements were maintained for 1 to 6 months after participation. DISCUSSION: Despite differences in diagnosis among these participants with chronic neurological disorders, on average they were able to complete 80% of an intensive treatment schedule of 3 hours/day for 10 days with no adverse effects. It appears that some gains made during participation are maintained for a period of time after the end of training. IMT is a feasible intervention incorporating an intensive training approach to improve gait, balance, and mobility; however, a randomized trial is needed to further investigate the effects of the intervention.

A novel tubular scaffold for cardiovascular tissue engineering.

We have developed a counter rotating cone extrusion device to produce the next generation of three-dimensional collagen scaffold for tissue engineering. The device can produce a continuously varying fibril angle from the lumen to the outside of a 5-mm-diameter collagen tube, similar to the pattern of heart muscle cells in the intact heart. Our scaffold is a novel, oriented, type I collagen, tubular scaffold. We selected collagen because we believe there are important signals from the collagen both geometrically and biochemically that elicit the in vivo -like phenotypic response from the cardiomyocytes. We have shown that cardiomyocytes can be cultured in these tubes and resemble an in vivo phenotype. This new model system will provide important information leading to the design and construction of a functional, biologically based assist device.

Novel 3D culture system for study of cardiac myocyte development.

Insufficient myocardial repair after pathological processes contributes to cardiovascular disease, which is a major health concern. Understanding the molecular mechanisms that regulate the proliferation and differentiation of cardiac myocytes will aid in designing therapies for myocardial repair. Models are needed to delineate these molecular mechanisms. Here we report the development of a model system that recapitulates many aspects of cardiac myocyte differentiation that occur during early cardiac development. A key component of this model is a novel three-dimensional tubular scaffold engineered from aligned type I collagen strands. In this model embryonic ventricular myocytes undergo a transition from a hyperplastic to a quiescent phenotype, display significant myofibrillogenesis, and form critical cell-cell connections. In addition, embryonic cardiac myocytes grown on the tubular substrate have an aligned phenotype that closely resembles in vivo neonatal ventricular myocytes. We propose that embryonic cardiac myocytes grown on the tube substrate develop into neonatal cardiac myocytes via normal in vivo mechanisms. This model will aid in the elucidation of the molecular mechanisms that regulate cardiac myocyte proliferation and differentiation, which will provide important insights into myocardial development.