No abstract

No abstract

No abstract

This paper describes the effects of therapeutic electrical stimulation (TES) on the wasting muscles in a patient with amyotrophic lateral sclerosis. The patient is a 47-year-old male, and he has a history of progressive muscle weakness and atrophy, affected more in the right side. Percutaneously indwelling intramuscular electrodes were implanted to the affected muscles in the right upper and lower extremities but no electrode in the corresponding left region. Within a month of TES therapy, a rapid improvement of extremity motion appeared in the TES treated side. Long-term application of TES more than 3 months increased the strength of the muscle which had been evidently weaker than the non-treated side. CT findings of both the upper and lower extremities with TES therapy showed an increase in the density and a reduction in the moth-eaten image. An increase in the thickness of the muscles was also observed in the TES treated side while deterioration was observed in the muscles on the non-treated side.

An Escherichia coli mutant, LL103, harboring a mutation (Ser15 to Phe) in ribosomal protein L7/L12 was isolated among revertants of a streptomycin-dependent strain. In the crystal structure of the L7/L12 dimer, residue 15 within the N-terminal domain contacts the C-terminal domain of the partner monomer. We tested effects of the mutation on molecular assembly by biochemical approaches. Gel electrophoretic analysis showed that the Phe15-L7/L12 variant had reduced ability in binding to L10, an effect enhanced in the presence of 0.05% of nonionic detergent. Mobility of Phe15-L7/L12 on gel containing the detergent was very low compared to the wild-type proteins, presumably because of an extended structural state of the mutant L7/L12. Ribosomes isolated from LL103 cells contained a reduced amount of L7/L12 and showed low levels (15-30% of wild-type ribosomes) of activities dependent on elongation factors and in translation of natural mRNA. The ribosomal activity was completely recovered by addition of an excess amount of Phe15-L7/L12 to the ribosomes, suggesting that the mutant L7/L12 exerts normal functions when bound on the ribosome. The interaction of Ser15 with the C-terminal domain of the partner molecule seems to contribute to formation of the compact dimer structure and its efficient assembly into the ribosomal GTPase center. We propose a model relating compact and elongated forms of L7/L12 dimers. Phe15-L7/L12 provides a new tool for studying the functional structure of the homodimer.