Using a conditioning-test paradigm, we studied the recovery function of tibial nerve somatosensory evoked potentials (SEPs) conditioned by preceding peroneal nerve stimulation. The inter-stimulus intervals (ISIs) ranged from 0 to 400 msec, where 0 msec indicated simultaneous arrival of tibial and peroneal nerve volleys at the L1 spine. The recovery curve was W-shaped, showing two peaks of SEP suppression, maximum at 6 msec ISI (1st phase) and 50-75 ISI msec (2nd phase). In the 1st phase suppression, we found distinct differences in wave forms between 0-2 msec ISI and 4-6 msec ISI. At 0-2 msec ISI, P40-N50-P60 amplitude decreased and latencies shortened, while P31 and N35 were unchanged. At 4-6 msec ISI, all peaks, possibly excluding P31, were markedly depressed. We attribute the former change to an "occlusive effect" and the latter to an "inhibitory effect," each mediated via a central synaptic network between the two nerves. The attenuation of the 2nd but not the 1st phase suppression by peroneal nerve block distal to the stimulating electrodes provided evidence that the 2nd phase suppression resulted primarily from interfering afferent signals generated by peroneal nerve peripheral receptors, activated by foot movement.

Adult↗

PubMedDate not supplied

Endoscopic and biopsy findings of the upper digestive tract in patients with amyloidosis.

Endoscopic and biopsy findings of the esophagus, stomach, duodenum, and colorectum were studied in 37 patients with amyloidosis involving the gastrointestinal tract. Endoscopic examinations revealed fine granular appearance, polypoid protrusions, erosions, ulcerations, and mucosal friability in many cases. These findings were most marked and noticed most often in the second portion of the duodenum. The frequency of amyloid deposition in the biopsy specimens was as follows; 100% in the duodenum, 95% in the stomach, 91% in the colorectum, and 72% in the esophagus. The degree of amyloid deposition in the duodenum, which was the highest of the entire gastrointestinal tract, significantly correlated with the frequency of endoscopic findings such as fine granular appearance and polypoid protrusions. Therefore, the two endoscopic findings described above are characteristic of this disease and may reflect amyloid deposition in the mucosa or submucosa of the alimentary tract. Our results indicate that for a diagnosis of amyloidosis, it is important to examine the upper gastrointestinal tract, especially the duodenum, using endoscopy and biopsy techniques.

Adult↗

PubMedDate not supplied

Endoscopic findings in Yersinia enterocolitica enterocolitis.

The endoscopic findings in the colon and terminal ileum in eight cases of Yersinia enterocolitica enterocolitis infection were studied. The diagnosis was based on the isolation of Y. enterocolitica in the feces and/or elevated serum antibody titers to the organism. Total colonoscopy was performed between 7 and 38 days (mean, 24 days) after the onset of symptoms. In all patients, the terminal ileum was affected, followed by frequent involvement of the ileocecal valve and the cecum, and less frequently, the ascending colon. In the terminal ileum, round or oval elevations with or without ulcers were detected. Small ulcers were detected on the ileocecal valve and in the cecum. These findings were observed even 4 to 5 weeks after the onset of symptoms, suggesting a relatively long course for this disease.

Adolescent↗