No abstract

Dissociated cells from 5- to 12-day-old chick embryo cerebral hemispheres were cultivated in polylysine-coated plastic Petri dishes. The polylysine substrate was observed to be favorable for the growth of neuronal cells, whereas glioblast proliferation was inhibited. The optimal conditions for the production of a predominantly neuronal culture were to use cerebral hemispheres from 7-day-old chick embryos, to dissociate the brain tissue mechanically and to seed the cells at a concentration range between 1.5 and 5 × 10⁶ cells/ml. The cultures were observed by phase contrast microscopy. Most cells grew fibers and differentiated into bipolar and multipolar neurons. These neurons were stained by thionine, which demonstrated the presence of Nissl bodies. The silver impregnation revealed the presence of neurofibrils within the nerve fibers. Acetylcholinesterase was found to be present in the neuronal cells, but absent in the glioblasts. Under our culture conditions the neurons survived for 10–12 days. This system should allow further studies on the effects of growth factors on the differentiation of isolated neurons as well as investigations on neuron-glial interrelationship.

No abstract

The paper describes a device (Paracycle), that uses functional neuromuscular stimulation to exercise subjects, explore FNS technology and provide paraplegics with locomotion. The Paracycle is a four-wheeled cycling vehicle that may be used as a stationary exercise device or for locomotion. It incorporates a fully adjustable seat and an electric motor to assist or retard the cycling motion, as well as speed and direction controls. Furthermore, it has braces to fasten the feet to the pedals and to stabilise the ankle, as well as gearing to enable subjects with very small forces to move the vehicle forward. Results are presented for two cases studies. Good stability of the leg was achieved during the cycling motion and this would appear to be a major advantage of functional neuromuscular stimulation cycling over functional neuromuscular stimulation gait. Important areas for future research include a better understanding of the biomechanics of functional neuromuscular stimulation cycling and the development of Paracycle-like devices that can be used independently by paraplegics.

Glial conditioned medium strongly stimulates the morphological maturation of cultured neuronal cells, while fibroblast and meningeal conditioned media have weaker effects.