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51.
Hiroyuki Kumamoto Takahiro Suzuki Kiyoshi Ooya 《Journal of oral pathology & medicine》2002,31(10):605-611
BACKGROUND: To clarify the possible role of nitric oxide (NO) and stress proteins in oncogenesis and cytodifferentiation of odontogenic epithelium. Inducible NO synthase (iNOS) and heat shock proteins (HSPs) were analyzed in ameloblastomas as well as in tooth germs. METHODS: Specimens of seven tooth germs, 36 benign ameloblastomas and five malignant ameloblastomas were examined by immunohistochemistry using antibodies against iNOS and 27-, 60- and 70-kDa HSPs (HSP27, HSP60 and HSP70). RESULTS: Immunoreactivity for iNOS was detected in normal and neoplastic odontogenic epithelial cells and was higher in malignant ameloblastomas than in tooth germs and benign ameloblastomas. HSP27 was expressed constitutively in all odontogenic epithelial cells in tooth germs and benign and malignant ameloblastomas. Expression of HSP60 and HSP70 was detected in normal and neoplastic odontogenic epithelial cells and was prominent in cells neighboring the basement membrane. HSP60 reactivity showed no apparent difference between normal and neoplastic odontogenic epithelium, whereas HSP70 expression was slightly higher in benign and malignant ameloblastomas than in tooth germs. CONCLUSIONS: Activation of iNOS might be associated with malignant potential of epithelial odontogenic tumors. Elevated expression of HSP70 is considered to be involved in neoplastic transformation of odontogenic epithelial cells. 相似文献
52.
Kentaro Kunimori Kiyoshi Harada Yutaka Maruoka Ken Omura 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2006,101(2):e23-e27
Trichorhinophalangeal syndrome (TRPS) type I is characterized by slowly progressing systemic osseous dysplasia, exhibiting craniofacial and other skeletal deformities. However, there have been few reports describing this syndrome after undergoing orthognathic surgery. In this report, we present a patient with TRPS I who successfully underwent orthognathic surgery. In addition, we examined the skeletal stability of the patient for 2 years after the surgery. 相似文献
53.
54.
Hiroko Koizumi Chikako Yasui Torn Fukaya Tetsuo Ueda Akira Ohkawara 《Experimental dermatology》1994,3(1):40-44
Abstract Substance P is a neuropeptide which is present in peripheral C nerve endings and released from them. Free nerve endings of C nerve are present in human epidermis. The effects of substance P on the transmembrane signaling system of pig epidermal sheets were previously reported. In these studies, a small amount of cells other than keratinocytes contaminated the epidermal sheets and the species difference from human was also noticed. Therefore we investigated the effects of substance P on cultured normal human epidermal keratinocytes. Alteration of intracellular free calcium (Ca2+) in single living keratinocytes was studied using an inverted fluorescence microscope and Ca2+ -sensitive dye, Fura 2-AM. Treatment of normal human epidermal kertinocytes with substance P resulted in an increase in inositol 1,4,5-trisphosphate and in intracellular Ca2+. Substance P inhibited DNA synthesis of the keratinocytes in a dose-dependent manner. These results are consistent with the view that substance P stimulates phosphatidylinositol-4,5-bisphosphate hydrolysis of human keratinocytes, resulting in inositol 1,4,5-trisphosphate-Ca2+ signal. 相似文献
55.
Analogues of erythrocyte protein 4.1, spectrin and ankyrin were examined in the thyroid gland of pig and rat by immunohistochemical techniques. Analysis with immunofluorescence microscopy revealed that the peripheral cytoplasm and apical-lateral plasma membrane of follicle epithelial cells of thyroid glands were stained with antibodies against erythrocyte protein 4.1, spectrin, or ankyrin. The results indicate that membrane skeletal protein lattice might exist in thyroid follicle epithelial cells. 相似文献
56.
T Katoh Y Fujimura S Arai S Koizumi 《[Zasshi] [Journal]. Nihon Kyōbu Geka Gakkai》1990,38(8):1255-1261
Postinfarction left ventricular aneurysms are pathophysiologically divided into true, functional and false aneurysm. On 14 patients treated by aneurysmectomy, we studied the difference of pre- and post-operative cardiac function between true aneurysms (9 patients) and functional aneurysms (5 patients). The aneurysm area, which is expressed as the end-diastolic perimeter (akinetic or dyskinetic area/left ventricular silhouette), was 51.6 +/- 7.7% in the true aneurysms versus 35.7 +/- 6.0% in the functional aneurysms. Preoperatively, patients with a true aneurysm had a more severe clinical status than those with a functional aneurysm (Six of nine patients with a true aneurysm were in New York Heart Association functional class III or IV). Postoperatively, all patients except one with a true aneurysm and one with a functional aneurysm improved in clinical status. Nonaneurysmal EF, that is the function of the nonaneurysmal left ventricle, has a significant correlation to postoperative LVEF (r = 0.57, p less than 0.05). Nonaneurysmal EF was 54 +/- 4% in the true aneurysm group versus 51 +/- 16% in the functional aneurysm group. LVEF improved significantly (p less than 0.05) from 31 +/- 11% preoperatively to 55 +/- 10% postoperatively in the group of true aneurysm, but did not improved significantly from 43 +/- 12% to 50 +/- 9% in the functional aneurysm group. The postoperative akinetic area was 8.1 +/- 9.1% in the true aneurysm group versus 17.8 +/- 11.5% in the functional group. We conclude that larger and more adequate resection of aneurysms improves the cardiac function in the true aneurysm group more than in the functional aneurysm group. 相似文献
57.
A rare case of a dissecting aneurysm of the P3 segment of the right posterior cerebral artery is presented that seems to have occurred in association with mild head injury. The patient was treated surgically because of repeated intramural hemorrhage and enlargement of the aneurysm. Proximal ligation produced thrombosis of the aneurysm without resulting in infarction in the region of the posterior cerebral artery. The mechanisms of the dissection, diagnosis, and treatment are briefly discussed. 相似文献
58.
Hisashi Sugiyama Toshie Kadono Minako Hoshiai Tetsushi Tan Keiichi Koizumi Hajime Sakamoto Simpei Nakazawa 《Catheterization and cardiovascular interventions》2004,63(3):346-350
We report here the first described case of utilizing gadolinium-based contrast material as the contrast agent during a catheter intervention treatment for pulmonary artery stenosis. The patient, a male infant with complex heart disease associated with a right isomerism, had a history of severe allergic reaction to iodine-containing contrast agents. A combination of digital subtraction angiography and a gadolinium contrast agent, however, provided us with good-quality images both before and after balloon angioplasty without any associated complications. This method should therefore be considered as an alternative angiographic procedure in children with a high risk of iodine-related allergic complications. 相似文献
59.
Emiri Tejima Bing-Qiao Zhao Kiyoshi Tsuji Anna Rosell Klaus van Leyen R Gilberto Gonzalez Joan Montaner Xiaoying Wang Eng H Lo 《Journal of cerebral blood flow and metabolism》2007,27(3):460-468
We tested the hypothesis that astrocytic matrix metalloproteinase-9 (MMP-9) mediates hemorrhagic brain edema. In a clinical case of hemorrhagic stroke, MMP-9 co-localized with astrocytes and neurons in peri-hematoma areas. In a mouse model where blood was injected into striatum, MMP-9 was colocalized with astrocytes surrounding the hemorrhagic lesion. Because MMP-9 is present in blood as well as brain, we compared four groups of wild type (WT) and MMP-9 knockout (KO) mice: WT blood injected into WT brain, KO blood into KO brain, WT blood into KO brain, and KO blood into WT brain. Gel zymography showed that MMP-9 was elevated in WT hemorrhagic brain tissue but absent from KO hemorrhagic brain tissue. Edematous water content was elevated when WT blood was injected into WT brain. However, edema was ameliorated when MMP-9 was absent in either blood or brain or both. To further assess the mechanisms involved in astrocytic induction of MMP-9, we next examined primary mouse astrocyte cultures. Exposure to hemoglobin rapidly upregulated MMP-9 in conditioned media within 1 to 24 h. Hemoglobin-induced MMP-9 was reduced by the free radical scavenger U83836E. Taken together, these data suggest that although there are large amounts of MMP-9 in blood, hemoglobin-induced oxidative stress can trigger MMP-9 in astrocytes and these parenchymal sources of matrix degradation may also be an important factor in the pathogenesis of hemorrhagic brain edema. 相似文献
60.
Shigeki Yamagishi Kiyoshi Koizumi Tomomi Hirata Kyoji Hirai Jiro Kurita Kazuo Shimizu 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2005,53(6):313-316
We report a 59-year-old woman who underwent thoracoscopic extirpation of the intrapulmonary cystic lymphangioma which was located in the subpleural space of the left upper lobe. A chest X-ray showed a solitary round nodule in the left pulmonary hilum. A computed tomography scan revealed a mass shadow at the interlobar region surrounding the interlobar pulmonary artery. A round nodule was recognized as low signal intensity on T1-weighted images by magnetic resonance imaging. There was biphasic signal intensity on T2-weighted images as well. Radiologically, we diagnosed this lesion as a benign cystic tumor in the lung. Thoracoscopic observation revealed a cystic lesion just beneath the visceral pleura of the upper lobe adjacent to the interlobular pulmonary artery. As this suggested a benign bronchogenic cyst, we performed extirpation of the cyst under thoracoscopy. After this operation, the cyst was diagnosed as an intrapulmonary cystic lymphangioma pathologically. 相似文献