Oral Leukoplakia Related to Malignant Transformation

AbstractOral leukoplakia and its malignant transformation are reviewed in this article. Oral leukoplakia is defined as a predominantly white lesion of the oral mucosa that can not be characterized as any other definable lesion; however, the lesion must be confirmed histopathologically by biopsy in order to discuss malignant transformation of oral leukoplakia. Malignant transformation rates of oral leukoplakia range from 0.13 to 17.5%, while the rates of five-year cumulative malignant transformation range from 1.2 to 14.5%. Some reports found a high incidence of malignant transformation in older patients. Chewing tobacco and smoking are distinct risk factors particularly among males in certain countries; however, other countries have noted that females or non-smokers may be at risk of malignant transformation. HPV has been detected in oral dysplasia lesions and cancer in non-smokers. Conflicting reports have been presented regarding the malignant transformation of oral leukoplakia with epithelial dysplasia; however, we and some authors believe that epithelial dysplasia is an important factor in the malignant transformation of oral leukoplakia. The majority of researchers showed non-homogenous leukoplakia as a risk factor, although different terms have been used to describe these lesions. There may be several routes to malignant transformation of oral leukoplakia, including transformations induced by carcinogenesis due to betel quid chewing or smoking, or by HPV infection. While no definite treatment modalities for oral leukoplakia have been established, we suggest surgical therapy with an adequate safety-margin and well-timed evaluation as an appropriate treatment in preventing malignant transformation

Objective measurement of nine gaze-directions using an eye-tracking device

Purpose: To investigate the usefulness and efficacy of a novel eye-tracking device that can objectively measure nine gaze-directions. Methods: We measured each of the nine gaze-directions subjectively, using a conventional Hess screen test, and objectively, using the nine gaze-direction measuring device, and de-termined the correlation, addition error, and proportional error. We obtained two consecu-tive measurements of the nine gaze-directions using the newly developed device in healthy young people with exophoria and investigated the reproducibility of the measurements. We further measured the nine gaze-directions using a Hess screen test and the newly developed device in three subjects with cover test-based strabismus and compared the results. Results: We observed that the objective measurements obtained with the newly developed gaze-direction measuring device had significant correlation and addition error compared to the conventional subjective method, and we found no proportional error. These measure-ments had good reproducibility. Conclusion: The novel device can be used to observe delayed eye movement associated with limited eye movement in the affected eye, as well as the associated excessive movement of the healthy eye in patients with strabismus, similar to the Hess screen test. This is a useful device that can provide objective measurements of nine gaze-directions

Gene expression changes during caste-specific neuronal development in the damp-wood termite Hodotermopsis sjostedti

<p>Abstract</p> <p>Background</p> <p>One of the key characters of social insects is the division of labor, in which different tasks are allocated to various castes. In termites, one of the representative groups of social insects, morphological differences as well as behavioral differences can be recognized among castes. However, very little is known about the neuronal and molecular bases of caste differentiation and caste-specific behavior. In almost all termite species, soldiers play defensive roles in their colonies, and their morphology and behavior are largely different from workers (or pseudergates). Therefore, we predicted that some genes linked to defensive behavior and/or those required for neuronal changes are differentially expressed between workers and soldiers, or during the soldier differentiation, respectively.</p> <p>Results</p> <p>Using the brain and suboesophageal ganglion (SOG) of the damp-wood termite <it>Hodotermopsis sjostedti</it>, we first screened genes specifically expressed in soldiers or during soldier differentiation by the differential display method, followed by quantitative real-time polymerase chain reaction. No distinctive differences in expression patterns were detected between pseudergates and soldiers. In the course of soldier differentiation, however, five genes were found to be up-regulated in brain and/or SOG: 14-3-3epsilon, fibrillin2, beta-tubulin, ciboulot, and a hypothetical protein containing a SAP motif. Some of these genes are thought to be associated with cytoskeletal structure or motor-associated proteins in neuronal tissues.</p> <p>Conclusion</p> <p>The identified five genes could be involved in soldier-specific neuronal modifications, resulting in defensive behaviors in termite soldiers. The temporal expression patterns of these genes were consistent with the neuronal changes during soldier differentiation, suggesting that molecular machineries, in which the identified factors would participate, play important roles in behavioral differentiation of termite soldiers.</p

Effects of Ground Improvement and Armored Embankment to the Displacements of the Seawalls and Back Fill During Earthquake

Large shaking table tests of the caisson type seawalls under various conditions were conducted in order to investigate the effects of the armored embankment and the improvement of sandy seabed and backfill by densification to the deformation of the seawalls during earthquake. Main results obtained from the shaking table tests were as follows : (1) Seaward horizontal displacement and tilting of the caisson were drastically reduced by the existence of the armored embankment in front of the caisson. (2) Improvement of the sandy seabed by densification method just under the rubble mound was much effective to reduction of the displacements of the caisson. (3) It was possible that the lateral movement of the liquefied backfill was reduced by the improvement of a part of the backfill just behind the caisson even though without the armored embankment in front of the caisson

Report of a case of acinic cell carcinoma of the upper lip and review of Japanese cases of acinic cell carcinoma of the minor salivary glands

Acinic cell carcinoma (ACC) is a malignant tumor of the salivary glands. The majority of ACCs occur in the parotid gland, and ACCs of the minor salivary glands (MSGs) are relatively infrequent. We describe here a patient with ACC of the upper lip. The patient was a 31-year-old male who presented with a nodular mass on the left upper lip. The preoperative diagnosis was benign tumor or cyst, and the lesion was surgically excised. The histological diagnosis was ACC. The postoperative course was uneventful. No recurrence or metastasis was detected at 13 months postoperatively. In addition, we retrospectively reviewed 21 reported Japanese patients with ACC of the MSGs. In 7 of the 21 patients, the preoperative diagnosis was benign tumor, and the tumors were resected without preoperative biopsy. Kaplan–Meier analysis showed that disease-free survival was worse in patients who underwent resection with a preoperative diagnosis of benign tumor than in patients who underwent resection with a preoperative diagnosis of malignant tumor. The rate of recurrence was higher for ACCs assumed to be benign lesions on a purely clinical basis, or without an accurate preoperative biopsy. ACCs of the MSGs are easy to be misdiagnosed for benign lesions such as mucous cysts or hemangiomas. Correct preoperative diagnosis and initial therapy may therefore be the most important prognostic factors