Biomedical subjects

S Kanda

Publications and source records attributed to S Kanda.

273 records · Page 16Linked to original sources

PubMedDate not supplied

Changes of auditory brainstem responses in electrolyte-induced myelinolysis in rats. Role of hyponatremia and hypernatremia.

Electrolyte-induced myelinolysis was produced in rats to evaluate electrophysiological derangement in the brainstem. Auditory brainstem responses (ABRs) were used to assess the brainstem function. Rats treated with hypertonic saline for 2 days had normal interpeak latencies in ABRs. Rats treated with vasopressin-induced hyponatremia alone and those with hypertonic saline after 3 days of hyponatremia had significantly prolonged interpeak latencies between waves II-III and III-IV in ABRs. These prolongations indicate electrophysiological derangement of the upper pons and mesencephalon in hyponatremic rats as well as in rats with hyponatremia followed by hypernatremic myelinolysis. In view of these data, hyponatremia may be a prerequisite for electrolyte-induced myelinolysis and electrolyte derangements such as hyponatremia, and rapidly correcting hypernatremia may be the cause of electrolyte-induced myelinolysis in rats.

Animals↗

PubMedDate not supplied

The role of macrophages in osteoclast neogenesis in vivo: quantitative analysis of osteoclasts and macrophages in endochondral bone development in rats treated with hydrocortisone or calcitonin.

Osteoclasts and macrophages in endochondral bone of rats were analyzed after long-term treatment with hydrocortisone (HC) or elcatonin (ECT). The growth plate-metaphysis junction ( GPMJ ) of the HC-treated bones showed increased numbers of osteoclasts, but the incidence of osteoclast profiles with ruffled borders was low and the cells had fewer nuclei. The number of macrophages in the GPMJ of HC-treated bone did not significantly differ from that in the control. In the metaphyseal trabecular (MT) region macrophages were numerous, but osteoclasts were depleted. Compared to controls the ECT-treated osteoclasts in the GPMJ had an increased number of nuclei per cell, and the incidence of osteoclast profiles with ruffled borders was reduced. There was a small increase in the number of osteoclasts and a large increase in the number of macrophages. The osteoclasts in the MT regions of ECT-treated bones were significantly larger compared to controls. The macrophages did not differ in number from the controls. This investigation supports the proposal that the GPMJ is the principal site of osteoclasts neogenesis. Discrepancies in features of osteoclasts in the GPMJ and MT regions of each treatment group were probably due to a difference in peroid when the osteoclasts were exposed to the drugs.

Animals↗

PubMedDate not supplied

Sonography for the detection of cervical lymph node metastases among patients with tongue cancer: criteria for early detection and assessment of follow-up examination intervals.

BACKGROUND AND PURPOSE: Because the presence of cervical metastasis is one of the factors influencing the outcome of patients with carcinoma of the head and neck, its early detection is potentially very important. The purpose of this study was to evaluate the characteristic changes of cervical metastasis revealed by sonography during follow-up and to assess an adequate interval for follow-up sonography of the neck among patients with tongue cancer. METHODS: Forty-three of 44 consecutive patients with squamous cell carcinoma of the tongue, who had undergone interstitial brachytherapy, were examined with sonography of the neck during the posttherapeutic follow-up period. RESULTS: Seventeen cervical lymph node metastases were found in 12 of 43 patients during follow-up. Of these 17 cervical metastases, 16 (94.1%) were accurately diagnosed and one (5.9%) was misdiagnosed as nonmetastatic based on sonographic findings. Sonography of the neck performed in seven patients at an interval of less than 1 month since the last follow-up imaging showed 9 (90.0%) of 10 metastases increased by up to 2 mm in short-axis diameter. Five patients who were followed up at an interval of more than 1 month since the last follow-up imaging had seven metastases increase by 3 to 8 mm in short-axis diameter or a change of echogenicity in the internal structure of lymph nodes or both. Pathologic examinations showed extranodal spread in 3 (42.9%) of these 7 metastases. CONCLUSION: Changes both in size and internal echogenicity can occur as quickly as 2 to 4 weeks between sonographic examinations. Therefore, in high-risk patients, or in those with suspicious sonographic findings, short-interval follow-up sonographic examinations are recommended at least during the first posttherapeutic year. Our findings suggest that follow-up sonography of the neck should be performed monthly, at least during the first posttherapeutic year.

Adult↗