Yasufumi Horinouchi

Ultrasonographic evaluation of inflammatory changes in the masseter muscle.

The ultrasonographic images of 32 patients with inflammatory change in the masseteric region were investigated to clarify the characteristic findings and to evaluate the utility of ultrasonography. Inflamed masseter muscles frequently demonstrated reduction of echo intensity and complete or partial absence of hyperechoic bands. The mean thickness of the masseter muscle on the unaffected side was 8.6 mm, whereas that on the affected side was 12.9 mm. Nine of 10 patients with heterogeneous hypoechoic area, but only 1 of 10 patients with homogeneous hypoechoic area, had received surgical treatment before ultrasonographic examination.

Dermoid cyst of the floor of the mouth: Lateral teratoid cyst with sinus tract in an infant

I n 1859 Roser reported that many of the ranulas and sebaceous cysts occurring at the base of the tongue were actually epidermoid tumors.’ Later, in 1891, Chair? reported that these tumors represented an embryonal entrapment of epidermal cells. They were thus recognized as a separate entity, and many cases have been reported since that time. Because of its unusual clinical and pathologic findings, we present the following case of a dermoid cyst arising in the floor of the mouth.

Mechanisms of vancomycin-induced histamine release from rat peritoneal mast cells

The mechanisms of vancomycin (VCM)-induced histamine release were studied with rat peritoneal mast cells. VCM (>1×10−3M) released histamine from the isolated mast cells in a dose-dependent and noncytotoxic manner. In the absence of extracellular Ca2+, the histamine release was reduced markedly. When the intracellular Ca2+ was depleted, it was further decreased. The Fura-2-loaded single mast cells showed a biphasic increase in the intracellular Ca2+ concentration ([Ca2+]i) by VCM: the first transient and the second sustained components. In the absence of extracellular Ca2+, the transient component was unchanged, while the sustained component was eliminated completely. The IP3 content in the mast cells increased within 10 s after the application of VCM. These results suggest that VCM releases histamine from rat peritoneal mast cells via an IP3 production and increase in [Ca2+]i.

Benign mesenchymoma of the tongue. Report of a case, with review of the literature.

A benign mesenchymoma of the dorsal midtongue in an 88-year-old woman is presented. The tumour was excised under local anaesthesia, and microscopic examination revealed cartilage, bone, striated muscle, peripheral nerve, adipose and myxoid tissue, and blood vessels in addition to fibrous tissue. Eight cases including ours were found in the literature.