Plastic Bronchitis of Human Bocavirus 1 Detected by Comprehensive Polymerase Chain Reaction of Mucus Casts

The time course of orthograde and retrograde degeneration after axonotomy was established for a pair of identified interneurons in the crayfish. The medial giant interneurons originate in the brain and send axons the entire length of the animal. These axons were transected midway along their course. The proximal portions of the axons continued to conduct impulses and maintained their synaptic connections for at least 1 year, but were often extremely convoluted, possibly indicating hypertrophy. The distal portions of the axons gradually withered away after transection, as evidenced by decreasing conduction velocities and cross-sectional area, but orthograde degeneration was extremely slow, and the isolated distal axons were still capable of impulse conduction and synaptic transmission up to 5 months later.