Ultrastructure of the taste pores and taste pits of human taste buds / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To observe the ultrastructural features of taste pores and taste pits of human taste buds.</p><p><b>METHODS</b>Three samplers obtained randomly from adults were divided into two perts, and transmission electron microscopy and scanning electron microscopy were used to observe the fine structure of taste buds in human circumvallate papillae.</p><p><b>RESULTS</b>The longer diameter of the taste pores was 1.02 - 7.36 microm, and most of taste pores contained no taste hair and dense material, and the profile of taste pit was triangular.</p><p><b>CONCLUSIONS</b>Taste hair and dense material were seldom observed in most of taste pores.</p>

Clinicopathological and immunohistochemical study of oral teratoid cyst / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate clinicopathological and immunohistochemical features of 31 cases of oral teratoid cyst.</p><p><b>METHODS</b>Thirty-one cases of oral teratoid cyst according with Meyer's diagnosis criteria were retrospectively studied and their histochemistry and immunohistochemistry were performed from the files of Department of Pathology, School of Stomatology, Wuhan University between 1963 and 2003.</p><p><b>RESULTS</b>Twenty-seven cases (87.10%) were children, and twenty-four cases were congenital. The ratio of male-to-female was 1:0.55, and the affected sites were floor of mouth (22 cases) and tongue (8 cases). Clinical findings were nonspecific, and prognosis was good following complete excision. Histology indicated that squamous, respiratory and/or gastrointestinal epithelium consistiuted basic structure of teratoid cyst in addition to simple cuboidal epithelium in 8 cases. Antibody against AE1/AE3 was strongly expressed and CK16 was weak in four types of epithelial lining of oral teratoid cyst. Expression of AE1, CK7, 8/18, 19 varied in superficial, suprabasal and basal cells of squamous epithelium but were strong in respiratory, gastrointestinal and simple columnar epithelium; only gastrointestinal epithelium expressed CK20 heterogeneously.</p><p><b>CONCLUSIONS</b>Oral teratoid cyst showed the highest incidence in children, and floor of mouth and tongue were mostly affected sites. Features of histology were complex, and immunohistochemistry indicated that epithelium of oral teratoid cyst shared similar patterns of cytokeratin with counterpart of normal tissues, showing different origin and differentiation of epithelial lining of the present cyst.</p>

A clinicopathological study of 14 cases of oral granular cell tumor / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To describe clinical and histological features of oral granular cell tumor (OGCT)and discuss their proliferative activity.</p><p><b>METHODS</b>Clinical and microscopic features were assessed in 14 cases of OGCT collected from the department of oral pathology, college of stomatology of Wuhan University between 1970 and 2003. Immunohistochemical analysis was carried out using antibodies to S-100, NSE and Ki-67 and follow-up was obtained in all cases.</p><p><b>RESULTS</b>Tongue was the most commonly affected location (13/14). The average age was 32.6 years (range 11 to 50). OGCT occurred more commonly in females (2.5:1). Histologically, the lesions consisted of polygonal cells with abundant, granular cytoplasm. Eleven cases had typical histological features, while 3 specimens were atypical. Growth patterns were expansive in 3/14 and invasive in 11/14, including 3 atypical cases. Immunohistochemical analysis disclosed that 100% of granular cells demonstrated moderated/strong staining for S-100 protein, neuron specific enolase (NSE). Nuclear immunostaining for Ki-67 was observed only in isolated granular cells. Seven patients with benign and two patients with atypical granular cell tumor had no recurrence and metastases. One patient with atypical granular cell tumor had local recurrence after 9 years and died of the disease 10 months later.</p><p><b>CONCLUSIONS</b>OGCT cells display low proliferation activity. Most OGCTs are benign but few have malignant potential and periodic follow-up is mandatory to detect malignant transformation.</p>

Expression of cathepsin K and IL-6 mRNA in root-resorbing tissue during tooth movement in rats / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the expression and the localization of Cathepsin K and IL-6 mRNA in root-resorbing tissue and to elucidate the molecular changes and mechanism of root resorption induced by tooth movement.</p><p><b>METHODS</b>Rats were subject to experimental tooth movement to induce root resorption. In situ hybridization was performed to identify the cells in root-resorbing tissue that produced Cathepsin K or IL-6 the difference of CK mRNA or IL-6 mRNA expression between root resorption group and control group was calculated by t-test.</p><p><b>RESULTS</b>Cathepsin K mRNA was highly and selectively expressed in multinuclear odontoclast and IL-6 mRNA expressed in fibroblast, osteoblast, osteocyte and cementoblast. The expression of Cathepsin K mRNA and IL-6 mRNA in root-resorbing tissue increased evidently compared with the normal periodontium.</p><p><b>CONCLUSIONS</b>Odontoclast in the root-resorbing tissue expresses Cathepsin K mRNA that participates in proteolysis during root resorption. IL-6 plays a very important role in the root resorption as a multifunctional cytokine.</p>

The study of proliferation of cells at the invasive tumor front of squamous cell carcinoma of tongue / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To evaluate the value of the invasive front grading (IFG), the proliferative activity of cells at the invasive tumor front (ITF) of squamous cell carcinoma (SCC) of tongue.</p><p><b>METHODS</b>All the tumors were graded using IFG grading. The expression of PCNA, Ki67 and staining and measurement of AgNOR number were evaluated at the ITF and the other parts of the same tumor.</p><p><b>RESULTS</b>The expression of PCNA (P < 0.001), Ki67 (P < 0.001), AgNOR number (P < 0.001) at the ITF were higher than those of other parts. The IFG score was significantly correlated with the expression of PCNA (P < 0.05), AgNOR number (P < 0.01) at the ITF. The complete IFG score (P < 0.01) was significant in both univariate and multivariate cox analysis; the AgNOR number at the ITF (P < 0.05) was only significant in univariate analysis (P < 0.05).</p><p><b>CONCLUSIONS</b>The ITF of SCCs of tongue differentiate poorer than the other parts and is active in proliferation. The complete IFG score and the AgNOR number at the ITF could be a valuable indication to predict the prognosis of SCCs of tongue.</p>

High-resolution electron microscopy of carious dissolution of enamel nano-crystals / 中华口腔医学杂志

<p><b>OBJECTIVES</b>To investigate the carious dissolution mechanism of enamel apatite nano-crystals at lattice fringe level and the possible correlation between the carious dissolution and the appearance of central dark line (CDL) in enamel crystals.</p><p><b>METHODS</b>The body of the lesion in incipient enamel caries was observed by high resolution transmission electron microscopy (HRTEM, JOEL-2010 operating at 200 kv), combined with selected-area argon-ion-beam thinning technique.</p><p><b>RESULTS</b>In the body of the lesion, the preferential core dissolution was found in most of enamel nano-crystals, whereas the peripheral dissolution of individual crystal could be occasionally observed. The initial carious dissolution of individual enamel apatite crystal occurred as a number of small electron-lucent spots along the central dark line with blurry, bent or disconnected lattice fringes. These small electron-lucent spots fused with each other to form large electron-lucent areas. Finally the central perforation was frequently seen in the crystals. The CDL always appeared in the same place with central perforation in carious crystals, which could be seen to extend along the CDL.</p><p><b>CONCLUSIONS</b>The initial carious dissolution is directly related to the lattice defects in the enamel nano-crystals. The preferential core dissolution can be partly ascribed to the CDL, which is presumed to be particularly susceptible area to caries.</p>