Solenochilus Springeri (White & St. John, 1868) from the Pennsylvanian of Southern Iowa

The unique Pennsylvanian nautilid Solenochilus springeri is described with reference to material from the lower Cherokee Group (Atokan or Desmoinesian) of Marion County, Iowa, and the Bloyd Formation (Morrowan) of northwestern Arkansas. The species was based originally on a specimen, now lost, from Adair County, Iowa; a neotype is selected from the Marion County collections. The detailed morphology of the pair of dorsolateral spines which characterize mature Solenochilus is described for the first time. These spines, whose length approximates the width of the mature body chamber, are hollow throughout. Each spine originated as a lateral expansion of a prominent dorsolateral ridge located on the umbilical shoulder

Stenolobulites n. gen., Early Permian ancestor of predominantly Late Permian Paragastrioceratid subfamily Pseudogastrioceratinae

20 p., 10 fig.http://paleo.ku.edu/contributions.htm

Polyethylene glycol (PEG) and other bioactive solutions with neurorrhaphy for rapid and dramatic repair of peripheral nerve lesions by PEG-fusion

BACKGROUND: Nervous system injuries in mammals often involve transection or segmental loss of peripheral nerves. Such injuries result in functional (behavioral) deficits poorly restored by naturally occurring 1-2 mm/d axonal outgrowths aided by primary repair or reconstruction. "Neurorrhaphy" or nerve repair joins severed connective tissues, but not severed cytoplasmic/plasmalemmal extensions (axons) within the tissue. NEW METHOD: PEG-fusion consists of neurorrhaphy combined with a well-defined sequence of four pharmaceutical agents in solution, one containing polyethylene glycol (PEG), applied directly to closely apposed viable ends of severed axons. RESULTS: PEG-fusion of rat sciatic nerves: (1) restores axonal continuity across coaptation site(s) within minutes, (2) prevents Wallerian degeneration of many distal severed axons, (3) preserves neuromuscular junctions, (4) prevents target muscle atrophy, (5) produces rapid and improved recovery of voluntary behaviors compared with neurorrhaphy alone, and (6) PEG-fused allografts are not rejected, despite no tissue-matching nor immunosuppression. COMPARISON WITH EXISTING METHODS: If PEG-fusion protocols are not correctly executed, the results are similar to that of neurorrhaphy alone: (1) axonal continuity across coaptation site(s) is not re-established, (2) Wallerian degeneration of all distal severed axons rapidly occurs, (3) neuromuscular junctions are non-functional, (4) target muscle atrophy begins within weeks, (5) recovery of voluntary behavior occurs, if ever, after months to levels well-below that observed in unoperated animals, and (6) allografts are either rejected or not well-accepted. CONCLUSION: PEG-fusion produces rapid and dramatic recovery of function following rat peripheral nerve injuries