An ultrastructural study of oncocytoma and oncocytic carcinoma of the parotid gland

One case of oncocytoma and another of oncocytic carcinoma of the parotid gland are reported with ultrastructural studies. The incidence of oncocytoma varies from 0.1% to 1.4% of all parotid gland tumors, while oncocytic carcinoma is extremely rate. The oncocytoma was composed of polyhedral cells with fine eosinophilic granular cytoplasm and a rounded nucleus. The tumor cell clusters were surrounded by basement membrane. The tumor cells of the oncocytic carcinoma were also characterized by eosinophilic cytoplasm, but cellular atypia and mitotic figures were found. Electron microscopically, the cytoplasm of the oncocytoma was packed with abundant mitochondria. They were oval or elongated in shape with stacked cristae. Although the tumor cells of the oncocytic carcinoma also contained many mitochondria, their number was less than that of the benign case, and stacked cristae were very few. Basement membrane was not seen. The ultrastructural characteristics of oncocytoma and oncocytic carcinoma of the parotid gland are discussed with reference to previous reports.     

Preliminary study on vestibular-evoked myogenic potential induced by bone-conducted stimuli.

OBJECTIVE: To study the relationship between vestibular-evoked myogenic potential evoked by air-conducted stimuli (A-VEMP) and those evoked by bone-conducted stimuli (B-VEMP). STUDY DESIGN: Prospective study. SETTING: University Hospital. PATIENTS: To determine the optimum stimulus conditions for B-VEMP, 40 ears of 20 healthy volunteers were used. To compare results of A-VEMP and B-VEMP, 60 ears of 30 healthy volunteers and 70 ears of 35 patients with unilateral vestibular disorder without conductive hearing loss were used. MAIN OUTCOME MEASURE: A-VEMP and B-VEMP were measured. Both examinations involved evaluation of the interaural ratio (IAR) of the p13-n23 peak-to-peak amplitude. To compare the relationship between A-VEMP and B-VEMP in healthy subjects and patients with unilateral vestibular disorder. RESULTS: The optimum stimulus for B-VEMP seemed to be a tone-burst sound with 8-ms duration at 250 Hz. In all healthy subjects, both A-VEMP and B-VEMP could be recorded. The mean IAR of B-VEMP (0.5 +/- 21.0%) was not significantly different from that of A-VEMP (0.2 +/- 19.4%). In patients with unilateral vestibular disorder, B-VEMP could not be detected in 10 ears in which A-VEMP also could not be detected. The IAR of A-VEMP was strongly correlated with that of B-VEMP (correlation coefficient, 0.98). CONCLUSION: The results of B-VEMP were almost the same as those for A-VEMP, at least, for patients without conductive hearing loss.     

Four cases of Kawasaki syndrome complicated with myocarditis.

BACKGROUND: Myocarditis frequently occurs in the acute phase of Kawasaki syndrome (KS), and a few severe cases have been reported. Four cases of myocarditis in KS required additional catecholamine treatment because of severe left ventricular dysfunction (LVD). CASE REPORTS: Three cases were relatively older children and 2 cases were complicated with encephalopathy. All 4 developed coronary artery abnormalities during convalescence. There was 1 case of LVD because of prolonged severe inflammation prior to administration of intravenous immunoglobulin (IVIG). The remaining 3 patients had normal values for ejection fraction before the administration of IVIG but decreased values (42-51%) and increased C-reactive protein levels after IVIG administration. These cases demonstrate an association between myocarditis in KS and severe or worsened inflammation. CONCLUSIONS: Even with prior normal echocardiography, careful observation of cardiac function may be necessary for patients with KS, especially older children, when inflammation deteriorates after administration of IVIG.     

Liver abscesses associated with stromal tumour of the stomach in a young woman.

A 23-year-old Japanese woman was admitted to hospital because of pyrexia and anaemia. She was found to have liver abscesses and a gastric submucosal mass by computed tomography and ultrasonography. Gastroscopy and a barium swallow revealed a round submucosal mass with a giant ulceration in the body of the stomach. The liver abscesses were successfully treated by percutaneous transhepatic drainage and intravenous administration of antibiotics. Cultures of the fluid from a liver abscess and gastric juice yielded alpha-haemolytic streptococci. Three weeks after the drainage, partial gastrectomy was performed. The tumour was diagnosed as a stromal tumour of the stomach (leiomyosarcoma) in the final histological report. The patient was discharged on postoperative day 17 without receiving adjuvant radio-chemotherapy. There have been no signs of recurrence two years after surgery. This is a rare case of a liver abscess associated with a stromal tumour of the stomach in a young patient. The bacteriological examinations suggested a possible association between these diseases.     

Prevalence of Raynaud's phenomenon in individuals not using vibrating tools

Vibration syndrome, especially Raynaud's phenomenon, has generally been observed in vibrating tool operators, but the frequency of Raynaud's phenomenon in individuals not using vibrating tools is unknown. The authors therefore conducted a survey on the prevalence of stiffness of hands, numbness of fingers, and Raynaud's phenomenon among the examinees of Gifu Prefectural Health Care Center and among the female students of Gifu Prefectural Nursing and Paradental School. The following results were obtained by this survey. 1. Prevalences of stiffness of hands, numbness of fingers and Raynaud's phenomenon in female students were 20.9%, 29.5% and 4.6%, respectively, which are 2-3 times higher than those in male adults. 2. The prevalence of Raynaud's phenomenon in female students aged 20-24 yr was equal to that of female adults aged 30-39. It was higher than that of those aged 18-19, 40-49 and 50-59. The prevalence of Raynaud's phenomenon in males did not show any difference by age group. 3. There was no occupational specificity in the prevalence of Raynaud's phenomenon, but the prevalences in male sales workers and in female professional and technical workers were higher than in other groups.     

Stimulation by a TRH precursor, TRH-Gly, of TSH and PRL secretion in rats: effect of starvation

The hypophysial activities of a possible direct precursor of thyrotropin (TSH)-releasing hormone (TRH), TRH-Gly, were evaluated in estrogen, progesterone-primed rats under urethane anesthesia. Intravenous administration of TRH-Gly in doses of 2-200 micrograms caused a significant and dose-dependent increase in blood TSH and prolactin (PRL). The stimulatory activity of TRH-Gly was 170 to 400-times less potent than that of TRH. The lower potency was confirmed by the action of TRH-Gly on the anterior pituitary cells in vitro. In starved rats, TRH-Gly apparently stimulated TSH and PRL secretion in a dose-dependent manner, and the stimulatory activity increased in starved rats as compared to normal controls. TRH-Gly did not affect [3H-MeHis]TRH binding in pituitary plasma membranes. These data imply that large amounts of TRH-Gly may have significant biological activities and these are potentiated in the starved condition.     

Subcortical connections of an 'oculomotor' region in the ventral bank of the anterior ectosylvian sulcus in the cat

Subcortical connections of an 'oculomotor' region in the ventral bank of the anterior ectosylvian sulcus (AESo), where eye movements were evoked by intracortical microstimulation, were studied in cats using a wheatgerm agglutinin horseradish peroxidase (WGA-HRP) tracing method. Following injection of WGA-HRP into the AESo, both anterogradely-labeled terminals and retrogradely-labeled cells were found with the highest concentration in the suprageniculate nucleus and the medial zone of the lateroposterior nucleus of the thalamus. In the brainstem, anterogradely-labeled terminals were found in the superior colliculus, the pontine reticular formation, the pontine tegmental reticular formation and the pontine nuclei.