The life span of Merkel cells (MCs) in normal epitheha is not known During the course of a previous study we found that the numerical density of MCs in the postrugal field (PRF) of the rat hard palate is very low in adults compared to juveniles We also noticed that PRFs of premature rats contain many ectopic MCs in epithelial surface layers It is of interest to know whether the reduction of MC density in PRFs is related to expansion of the area of PRFs or to the disappearance of MCs from the epithelium, and also whether the ectopic MCs mean cell turnover accompanied by apoptosis Therefore, we examined changes of numbers and numerical densities of MCs in PRFs of rats of various days of age Apoptosis of ectopic MCs was examined by a fluorescence nick end labeling combined with mmunohistochemistry for anti-cytokeratm 18 It was found that MCs in PRFs are reduced not only in numerical density but also in number during prematuration stages of rats There were no MCs that had a nucleus with nick end label, not only in surface layers but also in basal layers of PRF epithelium It was concluded that a large number of MCs are lost from epitheha of growing rat PRFs by desquamation and apoptosis is probably irrelevant to this phenomenon.
Recently the usefulness of Thallium 201 chloride (201T1) as a tumor imaging agent for various tumors has been reported However, the application of 201T1 SPECT to oral squamous cell carcinomas has not been established The purpose of this study is to investigate the usefulness of 201T1 SPECT in the assessment of malignancy or in the differential diagnosis of oral squamous cell carcinomas from inflammatory diseases. Thirty-two patients with 33 primary oral squamous cell carcinomas and 4 patients with inflammatory disease were studied SPECT images were acquired 15 minutes (early image) and 3 hours (delayed image) after the intravenous injection with 74MBq 201Tl, and then early uptake ratio (ER), delayed uptake ratio (DR), and retention index (RI) were measured The relations between these parameters and the size, the site, the degree of differentiation and the mode of invasion of the primary tumor were analyzed statistically. 201T1 SPECT correctly identified 32 of the 33 tumors, with 32 patients having oral squamous cell carcinoma, making the positive rate 97% Significant negative correlation was observed between RI and major or minor axis of tumors, therefore, this study revealed that RI was influenced by the size of a tumor In comparison with the average value of RI according to histopathological diagnosis, there was statistically significant difference (p=0011) between carcinomas (0 80±0 16, n=30) and inflammatory diseases (0 58±0 04, n=4), thus, it was supposed that differential diagnosis between them could be possible About the tumors with the range of minor-axis 20mm-40mm for little influence of tumor size to the RI, the tendency to decrease for the RI of well-differentiated group or low-invasive group was seen. For oral squamous cell carcinomas, 201T1 SPECT had a high positive rate The application was suggested for use in the differential diagnosis between inflammatory disease and carcinomas, where clinical usefulness could be expected.
The effect of conditioning stimulation of the internal capsule (IC) on nociceptive neurons in the rat medullary dorsal horn was investigated The animals were anesthetized with N_2O-O_2 (2 1) and 0 5%-halothane, and immobilized with pancuronium bromide Nociceptive neurons responding to noxious stimulations of the face and oral structures were recorded in the trigemmal caudal nucleus and the medial reticular subnuclei These neurons were classified into wide dynamic range (WDR) and nociceptive-specific (NS) types NS neurons were distributed in the superficial layers of the caudal nucleus and the dorsal part of the reticular subnuclei, whereas WDR neurons were distributed diffusely throughout the area except for the magnocellular layer of the caudal nucleus A test stimulus with a single rectangular pulse (5-70 V) was applied to the center of the receptive field, the nociceptive neurons exhibited short-and/or long-latency responses Both responses in about 53% of the nociceptive neurons were inhibited by conditioning stimuli to the ipsilateral IC with trains of 33 pulses (100-300 μA) at 330Hz The percent of inhibitory effects on the WDR neurons and NS neurons were 20 7±245% (n=16) and 165±137% (n=2), respectively The inhibitory effect continued for conditioning-test intervals of up to 500 msec Effective sites for conditioning stimulation were concentrated in the lateral side of the IC, through which the corticofugal fibers from the somatosensory and motor cortices pass The IC inhibitory effect was not affected by a systemic injection of naloxone Our findings suggest that the transmission of nociceptive information is modulated at the level of the medullary dorsal horn by the corticofugal fiber via the IC and that transmitters other than opioids are involved in the IC antmociception
われわれは八戸赤十字病院小児科から, Robin sequenceの生後12週男児の呼吸障害の改善のための対診を依頼された。患者は下顎後退,上気道閉塞,軟口蓋裂,舌小帯強直症がみられた。当科を受診前に,何度か重度の呼吸障害がみられ,2か月以上気管内挿管による呼吸管理か行われていた。患者の咽頭部の閉塞は,内規鏡検査によるSheyの分類のType 1であったため,われわれは生後15週でArgamaso変法による舌固定術を行った。術後2年5か月経過するが,以来患者にチアノーセは見られず,舌固定術は同患者に有効な治療法と思われた。
Cervical lymph node metastasis has a large impact on the prognosis of head and neck cancers, and it is very important to suppress cervical lymph node metastasis and primary lesion Neck dissection is performed to treat cervical lymph node metastasis, but in the head and neck region, occult cervical lymph node metastasis is a problem To clarify the mode of cervical lymph node metastasis in the head and neck cancer and to establish a treatment for cervical lymph node metastasis, the clinical and histopathological examinations of patients who underwent neck dissection at our department are reported in the present study. Subjects were 139 patients who underwent neck dissection on 149 sides at our department over a 28-year period between 1975 and 2003 From the 149 sides, a total of 1,862 lymph nodes were removed, an average of 12 5 nodes per side Of the 1,862 nodes, metastasis was confirmed in 172 nodes As for the location of metastatic lymph nodes, levels I, II and III accounted for 90% of the metastatic lymph nodes Based on histological findings at the initial visit, the incidence of metastatic lymph nodes was high for histologically malignant cancer In terms of cumulative survival, factors associated with poor prognosis included three or more metastatic lymph nodes, extranodal invasion, and metastatic lymph nodes at level III or IV. The above findings clarify the mode of metastasis to the cervical lymph nodes, and suggest the possibility that neck dissection for level V involvement can be omitted in some patients Further, as to the timing of neck dissection, there was no marked difference in prognosis between immediate neck dissection or subsequent neck dissection.
A case of gigantic hemangioma of the tongue with numerous phlebohths is reported The patient was a 77-year-old woman with a chief complaint of eating disturbance due to the swollen mass of the tongue Intra-oral examination revealed a lobulated, well circumscribed gigantic tumor mass of the tongue measuring 62×61×49mm, purplish-red in color On palpation, the tumor was compressible, and had numerous phlebohths In the tumor, over fifty radiopaque phlebohths were detected and no influx vessels were observed by angiography The tumor was surgically excised and the postoperative course was uneventful.