PubMed Health⌕ Search

Biomedical subjects

M Hisatomi

Publications and source records attributed to M Hisatomi.

At least 19 recordsLinked to original sources
PubMed2006

A case of recurrent ameloblastoma developing in an autogenous iliac bone graft 20 years after the initial treatment.

A case of recurrent ameloblastoma developing in an autogenous iliac bone graft 20 years after radical resection of primary mandibular ameloblastoma is presented. This case showed extensive bony resorption extending throughout the auto-grafted bone. Seeding to the graft bone was suspected as a cause of the recurrence in the iliac bone graft because wide destruction of the graft bone was observed without any prior signs and symptoms of intraoral mucosa. Consequently, extensive resection of bone as well as adjacent soft tissue was performed. Persistent follow-up examination is essential for management of ameloblastoma.

Aged↗
PubMed2005

Bone deformity showing a deep coronoid notch of the mandible in a patient with neurofibromatosis type 1.

We present a case of a 10-year-old girl with neurofibromatosis type 1 related skeletal dysplasia. In the present case, a unilocular radiolucency at the left coronoid notch visible on a panoramic radiograph was suspected to be a neurofibroma. However, only the presence of bone deformities was observed on CT. Fat-like tissue adjacent to the bone deformities inside the left mandibular ramus was revealed, and the presence of neurofibroma was unequivocally denied on the MR images. However, biopsy of the lesion suggested neurofibroma. The diagnostic imaging 18 months after the first visit did not revealed a tumourous mass. However, careful follow up is required even though we could not prove the presence the lesion on the basis of imaging.

Biopsy↗
PubMed2004

Radiographic examination of dentigerous cysts in the transitional dentition.

OBJECTIVES: To examine radiographically the relationship between the deciduous tooth and dentigerous cyst of the permanent successor during the transitional dentition. METHODS: From a retrospective review of all patients who visited our institution from April 1988 to August 2001, 70 patients under 16 years of age who had histologically confirmed dentigerous cysts that had developed from the central incisor to the second premolar were identified. These 70 patients were investigated using panoramic and periapical radiographs. RESULTS: In most cases (54 cases; 77.1%) the cyst was in the premolar region. Of the 54 premolars with dentigerous cysts, the overlying deciduous tooth had already been lost in 7 cases. Of the 47 remaining premolars with associated deciduous tooth, 35 (74.5%) had bone resorption of the periapical or bifurcation region, or irregular resorption of the associated deciduous tooth. Of the remaining 12 deciduous teeth with no periapical lesions, 9 had been treated with root canal therapy. Thus, 44 of these 47 cases (93.6%) had the possibility of inflammation at the deciduous tooth associated with the dentigerous cyst. Evidence from one case in the present study suggesting the process by which cyst development occurs is also given. CONCLUSION: Inflammatory change at the apex of the deciduous tooth may bring on a dentigerous cyst of the permanent successor.

Adolescent↗
PubMed2004

Radiographic examination of mesiodens and their associated complications.

OBJECTIVES: To examine mesiodens with regard to their status, their influence on adjacent teeth and their alteration during the follow-up period. METHODS: From retrospective reviews of all patients who visited our institution from 1990-2001, we identified 200 patients (256 mesiodentes) who were shown to have mesiodentes on the basis of a periapical radiograph, a panoramic radiograph or an axial radiograph. RESULTS: The number of supernumerary teeth was one in 146 cases (73%), two in 52 cases (26%) and three in 2 cases (1%). Of 256 mesiodentes, the direction of the crown of the mesiodens was inverted in 172 (67%), in a normal direction in 69 (27%) and in a horizontal direction with regard to the tooth axis in 15 (6%). Of the 147 mesiodentes for which axial radiography was performed, 131 (89%) were located at a palatal site against the dental arch, 16 (11%) overlapped the dental arch and none were at a labial site. Of our 200 cases, a delay of eruption of the permanent central incisor was seen in 12 (6%), malposition or rotation of the central incisor in 5 (2.5%) and dentigerous cyst formation arising from mesiodens in 22 (11%). Marked movement of the mesiodens was seen in 10 cases during the follow-up period of 5-7 years. Some complication arising from mesiodens was seen in 19.5% of all cases in our research. CONCLUSION: Although mesiodentes are not caused by malocclusion, they may cause it. A long period of impaction of mesiodentes may bring about dentigerous cyst formation or movement of the mesiodentes.

Adolescent↗
PubMed2003

Comparison of radiographic and MRI features of a root-diverging odontogenic myxoma, with discussion of the differential diagnosis of lesions likely to move roots.

Lesions that can produce divergence of the roots of teeth in the mandible include odontogenic cysts (odontogenic keratocysts, lateral periodontal cysts and radicular cysts), ameloblastomas, odontogenic myxomas, central giant cell granulomas, adenomatoid odontogenic tumors and aneurismal bone cysts, and other tumors. Moreover most benign jaw lesions can do this occasionally. However, when lesions--which show interradicular tear-shaped radiolucencies--are small it is often difficult to interpret them radiographically, because they do not show characteristic radiographic features. We describe a comparison of radiographic and magnetic resonance (MR) features of a root-diverging odontogenic myxoma, with discussion of the differential diagnosis of lesions likely to move roots. In addition, we discuss radiographic and MR features of possible lesions, which show similar radiographic findings to odontogenic myxoma.

Adult↗
PubMed2002

A case of complex odontoma associated with an impacted lower deciduous second molar and analysis of the 107 odontomas.

OBJECTIVE: Odontoma is a comparatively common odontogenic tumor, and it may lead to interference with the eruption of its associated tooth. Odontomas are mostly associated with permanent teeth, and they are rarely associated with deciduous teeth. The purpose of this report is to analyze 107 odontomas and to present a case of complex odontoma associated with a lower deciduous second molar. SUBJECT AND METHODS: The 106 cases were analyzed with regard to the following parameters: age, gender, location, erupted teeth, congenital missing teeth, radiological features, histopathological features and prognosis. RESULTS: Of the 106 cases, 41 were complex odontoma, 62 were compound odontoma, and three were immature odontoma. Compound odontoma had a predilection for the anterior. Complex odontoma occurred more often at the mandible. CONCLUSION: Odontoma located above the tooth crown of lower deciduous molar did not behave clinically different from that associated with permanent tooth. An odontoma could be related with a supernumerary tooth or a missing tooth. If odontomas, which interfered with tooth eruption, were extirpated early, the impacted teeth would probably erupt normally and be normal in shape.

Adolescent↗
PubMed2001

Odontogenic myxoma of maxillary sinus: CT and MR-pathologic correlation.

We showed the characteristic features of odontogenic myxoma in the maxillary sinus with computed tomography (CT), magnetic resonance imaging (MRI), and histopathological findings. CT images showed a multilocular soft tissue mass with bone destruction and thinning, and the characteristic finding of this lesion as strands of fine lacelike density. MRI revealed intermediate signal intensity on T1-weighted image and high signal intensity on T2-weighted image. MRI showed the erosive extent of the lesion into the adjacent structures. In contrast T1-weighted image, the peripheral portion of the lesion with a relatively large quantity of collagen bundles was enhanced, while the central portion with only mucoid component was not. The CT and MRI appearances correlated well with the histologic features and therefore were considered to be a useful tool for diagnosis of myxoma.

Adult↗
PubMed2001

MR imaging of nasopalatine duct cysts.

We describe the magnetic resonance (MR) features of two cases of nasopalatine duct cyst (NPDC), including the first presentation of T1-weighted images (WI). The signal intensity of the cases of NPDC showed homogeneous high signal intensity on both on T1 and T2WI, although most cysts of maxillofacial regions demonstrate low to intermediate signal intensity on T1WI. NPDC may commonly be of high signal intensity on T1WI, which is consistent with keratin and viscous fluids.

Adult↗
PubMed2001

CT and MR imaging of localized amyloidosis.

The localized form of amyloidosis affecting the head and neck region is rare. The characteristic features of localized amyloidosis appeared as multiple nodules on the tongue, lip, and cheek on computed tomography (CT) and magnetic resonance imaging (MRI). Contrast-enhanced CT scans represented this lesion as a marked nodular enhancement. MR features of this lesion appeared slightly low on T1-weighted images and slightly high on T2-weighted images compared with T1-T2 images of residual normal tongue. Time contrast intensity curves obtained from dynamic MRI rapidly increased to reach a plateau and gradually decreased during the late and delayed phases. MR findings suggest that such lesions might be comprised of fibrous tissue with abundant vessels. This report suggests that dynamic MRI might be helpful for diagnosing localized amyloidosis.

Aged↗
PubMed2000

A case of glandular odontogenic cyst associated with ameloblastoma: correlation of diagnostic imaging with histopathological features.

The glandular odontogenic cyst (GOC) is a rare odontogenic cyst. There has only been one reported case of the simultaneous presence of GOC and ameloblastoma. The radiographic features of GOC are well established but the MR findings have not been described. We report a case of GOC associated with ameloblastoma with special reference to the correlation of the diagnostic imaging with the histopathological features.

Ameloblastoma↗
PubMed2000

Two cases of polyostotic eosinophilic granuloma.

We report two cases of polyostotic eosinophilic granuloma (EG). Both plain radiographs and CT showed diffuse osteolytic lesions which suggested malignant tumors. Although EG was polyostotic, the prognosis was relatively good. Both cases developed new lesions over a follow-up period of 4-5 years and therefore further long-term review is needed.

Adult↗
PubMed1999

Enthalpy-Entropy Compensation Phenomenon Observed for Different Surfactants in Aqueous Solution.

Based on previously reported thermodynamic data such as changes of the Gibbs energy (DeltaG(m)( degrees )), the enthalpy (DeltaH(m)( degrees )), and the entropy (DeltaS(m)( degrees )) on micelle formation of more than 15 species of surfactants (including nonionic, anionic, and cationic surfactants), plots of DeltaH(m)( degrees ) vs DeltaS(m)( degrees ) (not of DeltaS(m)( degrees ) vs DeltaH(m)( degrees ), as is usually done) were made. For each surfactant, a linear relation having almost the same slope (1/307 K(-1)) within a small error (+/-2.3%) but a different intercept (varsigma) depending on the surfactant species was obtained, i.e., DeltaS(m)( degrees ) = (1/307)DeltaH(m)( degrees ) + varsigma, where 1/307 (K(-1)) means that the so-called compensation temperature (T(C)) is 307 K. Strictly speaking, T(C) ranges from 299 to 315 K, depending on the species. The intercept corresponds to the entropy change at a specific temperature giving DeltaH(m)( degrees ) = 0, at which the driving force of micelle formation comes only from the entropy term; this temperature is characteristic of the surfactant species. On the other hand, the compensation temperature has no significant meaning other than a mean temperature studied. Copyright 1999 Academic Press.

Journal Article↗
PubMed1997

Modulation of tyrosine kinase activity has multiple actions on insulin release from the pancreatic beta-cell: studies with lavendustin A.

We investigated the role of tyrosine kinases in the regulation of insulin release from a hamster beta-cell line, HIT T15, using selective tyrosine kinase inhibitors. Genistein increased the insulin release induced by glucose, but herbimycin A, tyrphostins and the erbstatin analogue failed to change the release. Lavendustin A at 0.1 nM-1 microM caused a concave-shaped inhibition of the insulin release stimulated by 7 mM glucose. The inhibitory effect of lavendustin A was overcome by higher concentrations of glucose. Lavendustin B, the negative control analogue, had no effect on the release. Lavendustin A at a nanomolar range progressively inhibited insulin release by high K+ (50 mM)-depolarization, whereas the inhibitor did not change the insulin release by Ca2+ ionophore (A23187). On the contrary, lavendustin A at 10 nM significantly increased insulin release when glucose-induced insulin release was enhanced by either 5 microM forskolin or 162 nM 12-O-tetradecanoylphorbol 13-acetate. Lavendustin A failed to influence the Ca(2+)-induced insulin release from HIT cells permeabilized with streptolysin-O. These findings suggest that tyrosine kinases may play versatile roles in the control of insulin release from the pancreatic beta-cell.

Animals↗
PubMed1996

Ca2+/calmodulin and cyclic 3,5' adenosine monophosphate control movement of secretory granules through protein phosphorylation/dephosphorylation in the pancreatic beta-cell.

We observed the movement of insulin granules in living transformed hamster pancreatic beta-cells (HIT T15) with a light microscope, where secretory granules are moving in the cytoplasmic space. Velocity of the typical granule movement was approximately 1.5 microns/sec. A stimulatory concentration of glucose activated the movement of the secretory granules. Forskolin, an activator of adenylate cyclase, increased the movement, resulting in changes in intracellular localization of the granules. Acetylcholine also activated the granule movement, whereas high K+ and tolbutamide, which cause Ca2+ influx through the voltage-dependent Ca2+ channel, had only little effect. The movement was abolished by BAPTA, the intracellular Ca2+-chelator. Activation of protein kinase C by 12-O-tetradecanoyl-phorbol 13-acetate failed to affect this movement. The motile events were inhibited by the calmodulin antagonist, W-7, and dramatically increased by okadaic acid, an inhibitor of protein phosphatases 1 and 2A. These results suggest protein phosphorylation by Ca2+/calmodulin- and cAMP-dependent protein kinases play a positive role in the control of the insulin granule movements, which results in potentiation of insulin release from the pancreatic beta-cell.

Acetylcholine↗
PubMed1991

[Development of hen's egg with low antigenicity for allergic patients].

We tried to prepare hen's egg with low antigenicity for allergy patients. First, we examined the effects of pH, heating temperature and time on antigenicity of egg. Dried whole egg solid (DES) was dissolved in the buffer solution adjusted at various pH and heated at 120 degrees C for 10, 20 and 40 min. As a result the antigenicity didn't significantly decrease. Next, DES was treated with succinic anhydride, sodium hydroxide and was heated. The antigenicity of the resultant modified whole egg solid (MES) was much lower than that of heated whole egg solid. Antigenicity was measured precisely by enzyme immunoassay, inhibition ELISA, RAST inhibition and PCA. It was found that the antigenicity of MES was decreased less than 1/1000 of that of DES. Then SDS-polyacryl-amide gel electrophoresis and gel filtration were performed to clarify the degree of the change of egg proteins. The bands and peaks which corresponded to ovalbumin and ovomucoid known to be major allergenic proteins responsible for egg allergy disappeared and new bands and peaks were detected.

Antigens↗