0000000000011867
AUTHOR
J. Michael Schröder
Homozygous mutations incaveolin-3cause a severe form of rippling muscle disease
Heterozygous missense mutations in the caveolin-3 gene (CAV3) cause different muscle disorders. Most patients with CAV3 alterations present with rippling muscle disease (RMD) characterized by signs of increased muscle irritability without muscle weakness. In some patients, CAV3 mutations underlie the progressive limb-girdle muscular dystrophy type 1C (LGMD1C). Here, we report two unrelated patients with novel homozygous mutations (L86P and A92T) in CAV3. Both presented with a more severe clinical phenotype than usually seen in RMD. Immunohistochemical and immunoblot analyses of muscle biopsies showed a strong reduction of caveolin-3 in both homozygous RMD patients similar to the findings in…
The fine structure of de-and reinnervated muscle spindles
Reinnervated muscle spindles in lower lumbrical muscles of rats studied 17 days to 24 months after crushing the sciatic nerve showed a series of alterations which have not been analysed, thus far, by electron microscopy. There was a striking increase of the number of intrafusal muscle fibers seen in approximately 20% of reinnervated spindles. These spindles showed 5–11 intrafusal muscle fibers whereas normal spindles usually contained 3–4 fibers only.
ALTERED RATIO BETWEEN AXON CALIBER AND MYELIN THICKNESS IN SURAL NERVES OF CHILDREN
ABSTRACT Maturation of myelin sheaths in normal sural nerves of children proceeds more slowly than axon growth. This asynchronous development of axons and myelin sheaths results in a statistically significant change of the ratio between axon caliber and myelin thickness during normal development. Therefore, myelin thickness of individual nerve fibers must be related to the size of the axons as well as to the age of the individuals studied. Abnormalities of the relationship between myelin thickness and axon diameter (primary hypomyelination of large, or small, or all fibers) were clearly identified in cases with metachromatic leukodystrophy, KRABBE's, DEJERINE-SOTTAS’, COCKAYNE'S and SANFILI…