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Object Adhesion molecules are suggested to play important roles in the pathogenesis of inflammatory diseases. We examined the expression of adhesion molecules in the muscles of human inflammatory myopathies. Methods We immunohistochemically studied the expression and distribution of two molecules in the selectin family (E- and P-selectin) and their common ligand sialyl Lewis X in 18 inflammatory myopathies, 13 disease controls, and 16 normal controls. Results In inflammatory myopathies, E- and P-selectin were upregulated on the surface of blood vessels, especially on the endothelial cells of the venules. Sialyl Lewis X was upregulated in the blood vessels, infiltrating leukocytes, and the surface of some atrophic myofibers. Some control muscles also showed weakly positive staining with these molecules, however, expression of these molecules was most striking in the muscles of inflammatory myopathies. Conclusion The results suggested that these molecules are upregulated in inflammatory myopathies and might play a role in the pathogenesis of inflammatory myopathies.(Internal Medicine 38: 632-635, 1999)

We present a male patient with Dejerine-Sottas disease phenotype, who had a small direct tandem duplication of the Po gene. The pathology of the sural nerve showed hypomyelinated fibers with absence of active demyelination and onion-bulb formations composed of two parallel layers of basement membrane, consistent with congenital hypomyelination neuropathy (CHN). However, his clinical features were more severe than those of previously reported CHN patients. A GGCA insertion was identified at the position of nucleotide 560 in the myelin protein zero (Po) gene. This insertional mutation was located in exon 4 coding for the transmembrane domain of the Po gene and caused a shift of reading frame, creating a stop codon. The mutation of the transmembrane domain probably has the largest impact on Po function. The mutation was not identified in both parents.

Glycinergic neurotransmission is a major inhibitory influence in the CNS and its disruption triggers a paediatric and adult startle disorder, hyperekplexia. The postsynaptic α(1)-subunit (GLRA1) of the inhibitory glycine receptor (GlyR) and the cognate presynaptic glycine transporter (SLC6A5/GlyT2) are well-established genes of effect in hyperekplexia. Nevertheless, 52% of cases (117 from 232) remain gene negative and unexplained. Ligand-gated heteropentameric GlyRs form chloride ion channels that contain the α(1) and β-subunits (GLRB) in a 2α(1):3β configuration and they form the predominant population of GlyRs in the postnatal and adult human brain, brainstem and spinal cord. We screened GLRB through 117 GLRA1- and SLC6A5-negative hyperekplexia patients using a multiplex-polymerase chain reaction and Sanger sequencing approach. The screening identified recessive and dominant GLRB variants in 12 unrelated hyperekplexia probands. This primarily yielded homozygous null mutations, with nonsense (n = 3), small indel (n = 1), a large 95 kb deletion (n = 1), frameshifts (n = 1) and one recurrent splicing variant found in four cases. A further three cases were found with two homozygous and one dominant GLRB missense mutations. We provide strong evidence for the pathogenicity of GLRB mutations using splicing assays, deletion mapping, cell-surface biotinylation, expression studies and molecular modelling. This study describes the definitive assignment of GLRB as the third major gene for hyperekplexia and impacts on the genetic stratification and biological causation of this neonatal/paediatric disorder. Driven principally by consanguineous homozygosity of GLRB mutations, the study reveals long-term additive phenotypic outcomes for affected cases such as severe apnoea attacks, learning difficulties and developmental delay.

Background Alternating hemiplegia of childhood (AHC) is a rare disorder characterized by transient repeated attacks of paresis and cognitive impairment. Recent studies from the U.S. and Europe have described ATP1A3 mutations in AHC. However, the genotype-phenotype relationship remains unclear. The purpose of this study was to identify the genetic abnormality in a Japanese cohort of AHC using exome analysis. Principal Findings A total of 712,558 genetic single nucleotide variations in 8 patients with sporadic AHC were found. After a series of exclusions, mutations of three genes were regarded as candidate causes of AHC. Each patient harbored a heterozygous missense mutation of ATP1A3, which included G755C, E815K, C927Y and D801N. All mutations were at highly conserved amino acid residues and deduced to affect ATPase activity of the corresponding ATP pump, the product of ATP1A3. They were de novo mutations and not identified in 96 healthy volunteers. Using Sanger sequencing, E815K was found in two other sporadic cases of AHC. In this study, E815K was found in 5 of 10 patients (50%), a prevalence higher than that reported in two recent studies [19 of 82 (23%) and 7 of 24 (29%)]. Furthermore, the clinical data of the affected individuals indicated that E815K resulted in a severer phenotype compared with other ATP1A3 mutations. Interpretation Heterozygous de novo mutations of ATP1A3 were identified in all Japanese patients with AHC examined in this study, confirming that ATP1A3 mutation is the cause of AHC.

Hyperekplexia is a rare, autosomal dominant neurological disorder characterized by hypertonia, especially in infancy, and by an exaggerated startle response. This disorder is caused by mutations in the alpha 1 subunit of the inhibitory glycine receptor (GLRA1). We previously reported two GLRA1 point mutations detected in 4 unrelated hyperekplexia families; both mutations were at nucleotide 1192 and resulted in the replacement of Arg271 by a glutamine (R271Q) in one case and a leucine (R271L) in the other. Here, 5 additional hyperekplexia families are shown to have the most common G-to-A transition mutation at nucleotide 1192. Haplotype analysis using polymorphisms within and close to the GLRA1 locus suggests that this mutation has arisen at least twice (and possibly four times). In 2 additional families, a third mutation is also presented that changes a tyrosine at amino acid 279 to a cysteine (Y279C). Five patients with atypical clinical features and equivocal or absent family history of hyperekplexia and 1 patient with a classical presentation but not family history are presented in whom a mutation in the GLRA1 gene was not detected. Thus, only clinically typical hyperekplexia appears to be consistently associated with GLRA1 mutations, and these affect a specific extracellular domain of the protein.

We report on a boy with Rieger syndrome, who had an apparently balanced reciprocal translocation between chromosomes 1 and 4. The clinical manifestations of this patient were characterized by irregular shaped pupils with a prominent Schwalbe line and an umbilical hernia. On cytogenetic studies, he was found to have a de novo reciprocal translocation 46,XY,t(1;4) (q23.1;q25), without visible deletion. His parents had normal chromosomes. A review of both cytogenetic and genetic linkage analyses with Rieger syndrome showed that chromosome 4q was involved. This and other previous reports suggested that the gene for Rieger syndrome is mapped to the 4q25-->4q26 segment adjoining the breakpoint.

Background In Duchenne muscular dystrophy (DMD), previous freeze-fracture electron microscopic studies demonstrated that muscle plasma membrane contained markedly decreased numbers of orthogonal arrays. Recent investigations showed that orthogonal arrays were composed of aquaporin 4 (AQP4) molecules, a member of the water channel protein family. Objectives To study whether the immunostainability of anti-AQP4 antibody is reduced in muscles of patients with DMD and whether, if it is reduced, the problem is at the genomic DNA, messenger RNA (mRNA), or posttranscriptional level. Patients and methods We analyzed the muscle and blood samples from 6 boys with DMD, 6 normal control subjects, and 12 patients with neuromuscular diseases at the protein, genomic DNA, and mRNA levels. At the protein level, immunohistochemical staining and immunoblot analysis were performed. At the genomic DNA and mRNA levels, the polymerase chain reaction and reverse transcription polymerase chain reaction, respectively, were used to screen for mutations in the AQP4 gene. Results At the protein level, immunohistochemical staining of our originally generated rabbit anti-AQP4 antibody in DMD muscles was markedly reduced. Most of the DMD myofibers showed negative staining with sporadic partially positive fibers at their myofiber surface, whereas the control muscles displayed continuous myofiber surface staining. Immunoblot analysis showed that the content of AQP4 in DMD muscles was remarkably decreased. Amplification of leukocyte genomic DNA by polymerase chain reaction showed that the patients with DMD had genomic DNA of the AQP4 molecule. Quantitative reverse transcription polymerase chain reaction demonstrated that DMD skeletal muscles contained markedly decreased AQP4 mRNA compared with controls. Conclusion The reduction in AQP4 in DMD muscles results from decreased levels of AQP4 mRNA in DMD myofibers.

Case Report: A 7-year-old boy presented with a 2-year history of convulsions. Birth history was unremarkable. His motor and mental development were normal until the onset of partial seizures of his face at the age of 5.3 years, usually upon awakening. CBZ failed to control seizures. At 6.3 years he began to display slow speech, drooling, and reading difficulties. Absence attacks began at age 7. Upon examination, muscle weakness and cerebellar ataxia and paresis were absent. He showed sudden loss of tone in the arms when eating or writing, considered to represent negative myoclonus. Laboratory examination including CBC, blood chemistry, CSF studies, and MRI all were normal. EEG showed continuous diffuse spike and wave bursts associated with focal spikes at mid-temporal and central area in the sleep record. Overnight sleep EEG showed continuous diffuse spike and wave bursts during slow wave sleep. The spike wave index was about 30% among slow wave sleep stages. During REM sleep, rapid eye movements disturbed the discharges of the diffuse spike and wave complex on EEG. His intelligent quotient was about 73 in the Tanaka-Binnet test. Attention was limited and he could not copy figures accurately due to pour eye-hand coordination. Speech therapy evaluation found word finding difficulty, paraphasia, slow speech, misuse of different consonants, distortion of vowels, and motor articulatory disturbance or motor aphasia. He lacked oral dyspraxia. During a hospital admission, ACTH-2 was administered intramuscularly 2 I times in addition to oral administration of valproate, phenytoin, and carbamazepine. Convulsions were controlled, and he gradually recovered from the motor aphasia. Diffuse abnormalities of EEG resolved, but focal spikes remained over centro-temporal areas during sleep. Cognitive function and vocabulary improved. Negative myoclonus of his hand disappeared. Several months after ACTH therapy, however, he suffered from moderate difficulties with word finding and the EEG deteriorated. Conclusions: ESES syndrome consists of “electrical status epilepticus during sleep”, “nonconvulsive status epilepticus with epileptic negative myoclonus”, “atypical benign partial epilepsy”, and “LandauKleffner syndrome“. According to Ohtahara, Landau-Kleffner syndrome is characteristic of auditory agnosia. There have been no reports of motor aphasia associated with this syndrome. The present case does not meet criteria for “electrical status epilepticus during sleep” because of the low spike-wave index but may be considered a variant of ESES. The distinctive features of this case are motor aphasia and negative myoclonus, as well as diffuse spike-waves during slow wave sleep. Long-term prognosis of this patient is not presently known.

pTa interactions have been studied. The total inelastic cross section, multiplicities, net charge distributions and inclusive momentum and rapidity spectra for produced particles are reported. The correlations between fast and slow particles are presented and the reaction mechanisms for multiparticle production in pTa interactions are discussed.