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Biomedical subjects

S J Oh

Publications and source records attributed to S J Oh.

At least 145 records · Page 8Linked to original sources
PubMed1993

Rimmed vacuoles of inclusion body myositis and oculopharyngeal muscular dystrophy contain amyloid precursor protein and lysosomal markers.

Rimmed vacuoles are small areas of focal destruction of muscle fibres, found in inclusion body myositis, oculopharyngeal muscular dystrophy and other muscle disorders. They are known to contain amyloid proteins, probably of beta-amyloid type. We examined rimmed vacuoles immunohistochemically in 12 patients with inclusion body myositis and two patients with oculopharyngeal muscular dystrophy with antibodies to beta-amyloid precursor protein and cathepsin B and D. We found evidence for the presence of all these markers in rimmed vacuoles. These results confirm the presence of beta-amyloid in rimmed vacuoles, and provide additional support for the hypotheses that rimmed vacuoles are of lysosomal origin and that lysosomes are probably important in the metabolism of amyloid precursor protein.

Aged↗
PubMed1993

Eosinophilic cystitis caused by vesical sparganosis: a case report.

We report a case of eosinophilic cystitis caused by vesical sparganosis. The patient had a history of eating raw frogs and presented with a mass in the bladder associated with peripheral eosinophilia and increased serum antibody titer against sparganum. Pathologically, a characteristic sinuous necrosis representing worm tracks was noted with massive diffuse infiltration of eosinophils in the wall of the bladder. The serum titer of sparganum-specific antibody returned to normal after surgical resection of the lesion. This finding emphasizes the importance of suspecting parasitic origin in cases of eosinophilic cystitis with a history of raw meat ingestion in endemic areas.

Cystitis↗
PubMed1993

Temperature effects on nerve conduction studies in patients with carpal tunnel syndrome.

This study was done to evaluate the effect of rising temperature on nerve conduction parameters in 22 patients with carpal tunnel syndrome (CTS). We wanted to find out whether diseased nerves responded to temperature rise in a different manner from normal controls. For this purpose a group of 20 healthy individuals were also tested. With rising temperature motor nerve conduction velocities increased, whereas latencies, amplitudes and duration of the compound muscle action potential decreased in both groups. These changes were not statistically significant between the two groups. Sensory nerve conduction parameters yielded basically similar findings except for a significantly smaller reduction in amplitude of the compound nerve action potential (CNAP) in the CTS group (p < 0.005). We conclude that there is a different response in the sensory CNAP amplitude between normal and CTS groups, but the same nerve conduction correction formulae for temperature can be used in CTS patients as in normal individuals in the event of low skin temperature.

Adult↗
PubMed1993

Pyridostigmine toxicity. Electrophysiological study.

A 54-year-old neurotic patient developed pyridostigmine-induced proximal weakness with daily 3600 mg of pyridostigmine. Detailed analysis of the RNS test showed three different types of responses which were reproduced in the in vitro nerve-muscle preparation, confirming that three different responses represent the different degree of pyridostigmine toxicity. One of responses was a pattern, thought to be typical of anticholinesterase toxicity: repetitive discharge and the maximal decrement in the second response followed by an increment (dip phenomenon). With reduction of pyridostigmine, clinical and electrophysiological improvement followed.

Action Potentials↗
PubMed1993

Quantitation of tendon reflexes in normal volunteers.

Ankle (ATR), patellar (PTR) and triceps (TTR) T-reflex responses were recorded in 48 limbs of 24 normal volunteers by delivering tendon taps with a hand operated electronic hammer. Latency to the onset of the triggered response, peak to peak amplitude and duration of the wave were measured after several repetitions. In all individuals, ATR and PTR were observed, while in 27% of limbs, TTR was absent. Shortest latency and duration of the elicited response were chosen to calculate normal means. Side differences were also evaluated. As amplitude showed a marked interindividual and side to side variation, lowest recorded value was selected to represent the lower limit of normal. Age, height, and leg length showed a good correlation with minimum ATR latency (p < 0.001). PTR latency correlated significantly with age, height, (p < 0.001) and thigh length (p < 0.001). No significant correlation existed between age, height, arm length and TTR latency (p > 0.01). In conclusion, ATR and PTR are acceptable tests in clinical practice, whereas TTR is not reliable, as it is technically difficult to elicit in some normal individuals.

Adult↗
PubMed1992

Vasculitic neuropathy mimicking Guillain-Barré syndrome.

Vasculitic neuropathy classically manifests as a subacute mononeuritis multiplex or polyneuropathy. Patients with a Guillain-Barré syndrome (GBS)-like presentation are usually not considered to have an underlying vasculitis. We describe 2 patients with rapidly progressive areflexic paralysis that was initially diagnosed as GBS, in whom vasculitic neuropathy was found histologically.

Aged↗
PubMed1992

Diagnostic sensitivity of the laboratory tests in myasthenia gravis.

The diagnostic sensitivity of three laboratory tests [serum antiacetylcholine receptor antibody (AChR-ab) assay, the repetitive nerve stimulation (RNS) test, and, the single fiber EMG (SFEMG)] for myasthenia gravis (MG) was compared in 120 patients. In all cases, at least one of the tests was abnormal. SFEMG was the most sensitive test, being abnormal in 92% of cases, followed by the RNS test (77%) and the AChR-ab assay (73%). SFEMG was abnormal in all cases with negative AChR-ab and RNS tests, in 97% of cases with negative AChR-ab assay, in 89% of cases with negative RNS test, and in 89% of cases with mild MG. We conclude that one of these three tests is abnormal in all cases of MG, and that the SFEMG is most sensitive in the diagnosis of MG.

Autoantibodies↗
PubMed1992

"Chronic sensory demyelinating neuropathy": chronic inflammatory demyelinating polyneuropathy presenting as a pure sensory neuropathy.

The clinical electrophysiological and histological features of 10 cases of "chronic sensory demyelinating neuropathy" (CSDN) are reported. This entity is characterised by: 1) subacute or chronic progression; 2) pure sensory neuropathy; 3) high spinal fluid protein in the majority of cases; 4) electrophysiological evidence of demyelination affecting motor as well as sensory nerve fibres; 5) demyelination on sural nerve biopsy and 6) good response to immunotherapy in progressive phase. It is believed that this entity represents chronic inflammatory demyelinating polyneuropathy (CIDP) presenting as pure sensory neuropathy.

Aged↗
PubMed1992

Chronic limb-girdle myasthenia gravis.

The existence of chronic "limb-girdle" form of myasthenia gravis (MG) has been questioned. We report here 12 such patients (10 women and two men) who constituted 3.8% of 314 MG patients in our study. The duration of disease ranged from 4 months to 7 years before the diagnosis. In almost all cases, the initial diagnosis was other than MG. None of the patients had any oculobulbar weakness. Acetylcholine receptor antibody was positive in five cases, although not all in the first assay. Repetitive nerve stimulation test was positive in all cases, although not necessarily the first time. Single-fiber EMG was positive in 11 cases. All patients responded to acetylcholinesterase inhibitors, and two thirds underwent immunotherapy. Diagnosis of limb-girdle MG requires a strong index of suspicion.

Adult↗
PubMed1992

A new mtDNA mutation in the tRNA(Lys) gene associated with myoclonic epilepsy and ragged-red fibers (MERRF).

Myoclonic epilepsy with ragged-red fibers (MERRF) has been associated with an A--G transition at mtDNA nt 8344, within a conserved region of the tRNA(Lys) gene. Although the 8344 mutation is highly prevalent in patients with MERRF, it is not observed in 10%-20% of the cases, suggesting genetic heterogeneity. We have sequenced the tRNA(Lys) gene of five MERRF patients lacking the common 8344 mutation. One of these showed a novel T-->C transition at nucleotide position 8356, disrupting a highly conserved base pair in the T psi C stem. The mutant mtDNA population was essentially homoplasmic in muscle but was heteroplasmic in blood (47%). Neither 20 patients with other mitochondrial diseases nor 25 controls carried this mutation. These findings suggest that tRNA(Lys) alterations may play a specific role in the pathogenesis of MERRF syndrome.

Adult↗
PubMed1991

Paraneoplastic vasculitic neuropathy: a treatable neuropathy.

Paraneoplastic vasculitic neuropathy has been recently described. We report the first case of this disorder which responded both clinically and electrophysiologically to cyclophosphamide treatment. A 54-year-old woman with a history of metastatic endometrial carcinoma in remission had asymmetrical polyneuropathy, electrophysiological findings consistent with a diffuse axonal neuropathy, high sedimentation rate and spinal fluid protein, and microvasculitis with axonal degeneration on nerve biopsy. The patient was treated with 150 mg of cyclophosphamide daily with gradual clinical and electrophysiological improvement.

Action Potentials↗
PubMed1991

Electrophysiological improvement following decompression surgery in tarsal tunnel syndrome.

Plantar nerve conduction studies 14 months to 3.5 years after decompression surgery in 3 cases of tarsal tunnel syndrome showed an improvement in motor conduction as well as in sensory nerve conduction. This electrophysiological improvement was associated with clinical improvement. However, minor abnormalities still existed in sensory nerve conduction in all 3 cases.

Action Potentials↗
PubMed1991

Identification of cellular factors that bind specifically to the Epstein-Barr virus origin of DNA replication.

The specific binding of HeLa cell factors to DNA sequences at the Epstein-Barr virus (EBV) latent origin of DNA replication was detected by gel shift experiments and DNase I footprinting analysis. These cellular proteins protected at least five discrete regions of the DNA replication origin. The viral protein required for EBV plasmid replication, EBV nuclear antigen 1 (EBNA-1), binds to specific sequences within the origin region. The HeLa cell proteins competed with EBNA-1 for binding to EBV origin DNA in vitro, leading to the possibility that these cellular proteins regulate EBV DNA replication by displacing EBNA-1 at the origin sites.

Antigens, Viral↗