[Functional and morphological changes in the cochlea of cholesterol fed guinea pigs].

Although sensory neural hearing loss stemming from hypercholesterolemia has received attention in recent years, no information is available about inner ear injuries resulting from this condition. In this study, we prepared guinea pig models at hypercholesterolemia and observed the inner ear with a transmission electron microscope, and also investigated the effect of vitamin E (Vit. E) on these injuries. One hundred and thirty-nine white male Hartley guinea pigs weighing a mean of 250 g each were divided into three groups. Group A consisted of the control animals, which were fed by a stock diet. Group B animals were fed by a hyperlipid diet (2.5% cholesterol, 0.25% cholic acid, and 7.5% cattle fat). Group C animals were fed by a Vit. E-added (50 units/100 g) hyperlipid diet. All the animals were sacrificed either one, two or three months after treatment and the cochlea duct vasculature, cochleal nerve fiber under spiral limbus, stria vascularis and inner hair cell and outer hair cell of Corti's organ was observed with a transmission electron microscope. Cholesterol, triglyceride, and TBARS values were concurrently measured in the serum. Auditory threshold was measured by auditory brain stem response (ABR). In groups B and C, cholesterol and triglyceride levels remained high,. The TBARS level elevated in group B but remained unchanged in groups A and C. In groups B and C, the threshold of ABR increased mildly. The cholesterol load led to injuries in the endothelium of the vasculature dominating the cochlea.(ABSTRACT TRUNCATED AT 250 WORDS)

[Case report of a foreign body in the nasal cavity: experimental research on limited damage].

We report here a case of serious nasal cavity tissue damage caused by a foreign substance, specifically, a button-shaped battery. The patient was a three-year-old boy who inserted a button-shaped battery into his left nasal cavity. On examination, we found necrosis of the nasal mucosa, cartilage and bone. In addition, the nasal cavity structure was severely damaged. In a follow-up experiment, we inserted a similar button-shaped battery, pre-soaked in a salt solution, into a rabbit's nasal cavity and measured daily changes in PH and discharge over time. In addition, we assessed how much nasal cavity tissue was damaged in a pathological specimen. We found that the chief factor mediating tissue damage, among those we tried, was strong base production with low voltage discharge. Under these conditions the nasal cavity is damaged in a short time.

Immunohistopathological properties of pleomorphic adenoma in salivary gland.

Fifty-eight salivary gland pleomorphic adenomas and 5 normal salivary glands were studied immunohistochemically with respect to intermediate filaments (keratin, desmin, and vimentin), actin and S-100 protein to observe the cellular differentiation of these tumor cells. Normal myoepithelial cells showed positive immunostaining for actin, vimentin and S-100 protein. Pleomorphic adenomas expressed keratin, vimentin and S-100 protein to various degrees, but only a few tumor cells of pleomorphic adenoma revealed actin. The results indicate that the tumor cells of pleomorphic adenoma show a bipolar differentiation capability of both epithelial and mesenchymal origins, although normal myoepithelial cells show only mesenchymal characteristics. The findings also support previous reports using light and electron microscopy, and also contribute to more precise diagnosis and a better understanding of the histogenesis of this tumor.