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M Terakado

Publications and source records attributed to M Terakado.

14 recordsLinked to original sources
PubMed2000

Diagnostic imaging with newly developed ortho cubic super-high resolution computed tomography (Ortho-CT).

OBJECTIVE: Ortho cubic super-high resolution computed tomography (Ortho-CT), which we have developed, is characterized by the small size of the unit and the ability to produce 3-dimensional images of high resolution with low-radiation doses. The purpose of this study was to investigate the clinical usefulness of Ortho-CT for the diagnosis of diseases in the oral and maxillofacial region. STUDY DESIGN: Ortho-CT has been used for the imaging diagnosis of a radicular cyst of the upper first molar, mesiodense, tooth fractures in the upper anterior region, a fracture of the condylar process, or presurgical evaluation for a dental implant. The usefulness of 3-dimensional images obtained by Ortho-CT was investigated in this study. RESULTS: Ortho-CT produced images of high resolution, enabling identification of the extent of the lesions and the fracture line, the condition of the impacted tooth, and the relationship with the maxillary sinus, mandibular canal, and adjacent teeth. CONCLUSION: Because Ortho-CT can take high-resolution 3-dimensional images at any tomographic layer with only 1 exposure, it is useful for the diagnosis of diseases in the oral and maxillofacial region.

Adult↗
PubMed1998

Squamous odontogenic tumor of the maxilla: report of a case.

A case of squamous odontogenic tumor (SOT) of the maxilla related to an embedded tooth in a 42-year-old Japanese woman is described. The patient felt a slight pain of her left maxilla 2 months before visiting our dental hospital. Histologically, the tumor consisted of a proliferation of round and elongated epithelial islands of well-differentiated squamous epithelium separated by a fibrous stroma. The epithelial nests varied in size, and were composed of cuboidal or squamous cells of basal layer and matured intermediate cells with prominent intercellular bridges. Although no calcified materials were found, microcystic degeneration was occasionally observed in the epithelial islands. These findings indicated that this tumor is a SOT of the maxilla.

Adult↗
PubMed1998

Basic studies on hydroxy apatite cement: I. Setting reaction.

Self-setting cements, alpha D-Cement and alpha DT-Cement, were prepared. They consisted of only the calcium phosphates alpha-TCP, TTCP and DCPA. These cements reacted and hardened in a moist environment at 37 degrees C. The powder X-ray diffraction patterns were taken to examine the conversion of their reactions as a function of time. The cements reacted and produced hydroxyapatite. The optimum powder/liquid ratio of alpha D-Cement was 2.0 and that of alpha DT-Cement was 1.8. The initial setting time of alpha D-Cement was 87.5 m and that of alpha DT-Cement was 107.5 m. The component and the product of these cements are calcium phosphates which are the putative minerals in teeth and bones. Therefore, these cements are useful for oral surgery as bone-filling materials.

Bone Substitutes↗
PubMed1997

A case of hemangiopericytoma of the buccal mucosa.

We report a 46-year-old woman who presented with a hemangiopericytoma in the buccal mucosa. At the 2-year postoperative examination, there was no evidence of recurrence or metastasis. The findings in the present case are compared with previous reports in the Japanese literature, with regard to patient age and sex, and lesion size, location, malignancy, local recurrence and metastasis.

Endothelium, Vascular↗
PubMed1996

Role of bilirubin as an antioxidant in an ischemia-reperfusion of rat liver and induction of heme oxygenase.

The anti-oxidative effect of bilirubin was investigated in an ischemia-reperfusion model of rat liver. The rat portal vessel and liver artery were ligated with a vascular clip, and after reperfusion the urine was collected at intervals. The amount of biopyrrins, the oxidative metabolites of bilirubin, in rat urine reached a maximum 4 hours after reperfusion. Biotripyrrin-a and -b which are biopyrrins isolated from human urine were included in urinary bilirubin oxidative metabolites of rats after reperfusion. The hepatic mRNA level of heme oxygenase-1 (HO-1), the rate limiting enzyme of bilirubin biosynthesis, reached a maximum after 4 hours. Furthermore, the hepatic activity of HO began to rise 4 hours after treatment and remained high until 24 hours posttreatment. These findings suggest that bilirubin acts as a physiological antioxidant in vivo in ischemia-reperfusion and that bilirubin biosynthesis is evoked by oxidative stress.

Animals↗
PubMed1996

The pyramidal cell layer of sector CA 1 shows the lowest hippocampal succinate dehydrogenase activity in normal and postischemic gerbils.

We examined regional differences in the activity of a mitochondrial respiratory enzyme, succinic dehydrogenase (SDH), in the hippocampi of normal and postischemic gerbils, using a quantitative imaging method. Gerbils (n = 21) without ischemia, and gerbils which had experienced 5 min of bilateral common carotid artery occlusion 12 h or 2 days previously, were sacrificed. Coronal sections of the brains were prepared for quantitative imaging of SDH activity and histological examination. In the control gerbils, SDH activity in the pyramidal cell layer of the CA 1 sector (Sommer's sector) was 106.3 +/- 10.3% (mean +/- SD; SDH activity as a percentage of the cerebellar SDH activity), which was lower than in the other subfields of the hippocampus. SDH activity in the oriens layer, stratum radiatum and lacunosum molecular layer of the CA 1 sector was lower than in the corresponding layers of the CA 2 and CA 3 sectors. After transient ischemia, SDH activity remained unchanged in the CA 1 sector. Histologically, selective neuronal necrosis was observed in the pyramidal cell layer of the CA 1 sector 2 days after ischemia. The observed low level of this mitochondrial respiratory enzyme in the pyramidal cell layer of the CA 1 sector should be taken into account as a possible trigger of the selective vulnerability of the region to ischemia.

Animals↗
PubMed1995

Glomus tumor of the upper lip.

A case of glomus tumor of the upper lip in a 57-year-old Japanese male is described. The patient had a tender swelling of the upper lip, and this was completely excised. The lesion was found to be encapsulated by fibrous connective tissue and composed of blood capillaries surrounded by sheets of epitheloid cells. Immunohistochemical examination revealed that the neoplastic cells were positive for S-100 protein, vimentin, desmin and actin. Although the endothelial cells of blood capillaries in the tumor tissue were positive for factor VIII, no reaction product was found in the tumor cells. These results suggested that the tumor cells had characteristics of smooth muscle cells.

Actins↗
PubMed1992

Nucleotide sequences of membrane-bound hydrogenase gene in Alcaligenes hydrogenophilus.

The nucleotide sequences of membrane-bound hydrogenase small (hupS) and large (hupL) subunit genes of hydrogen bacterium Alcaligenes hydrogenophilus were determined. The hupS and hupL genes encoded polypeptides of 363 and 619 amino acids, respectively. The hupS was located upstream of hupL with 35bp of intergenic region. The consensus ribosome-binding sequences were identified upstream of the start codons of hupS and hupL. Amino acid sequence of hupS is very similar to that of Rhodobacter capsulatus, Bradyrhizobium japonicum, and Azotobacter vinelandii at amino acid levels of 82%, 77%, and 81%, respectively. Similarly, amino acid sequence of HupL is similar to that of R. capsulatus, B. japonicum, and A. vinelandii at amino acid levels of 63%, 65%, and 68%, respectively. Northern hybridization analysis showed that hupS and hupL were co-transcribed, and addition of fructose to the culture medium remarkably decreased the amount of mRNA transcribed from hupS and hupL.

Alcaligenes↗
PubMed1987

[A case of multiple colorectal cancers repeatedly resected 5 times].

A case of successive metachronous colorectal cancers repeatedly resected 5 times during an 8-year period is reported. The 1st cancer was found in the sigmoid colon when the patient (male) was 32 years old. The 2nd was a mucosal carcinoma of the rectum which was locally excised. The 3rd was found in the ascending colon, and there was detected yet another small cancer in the adenoma in the resected specimen. The 4th and 5th cancers were found in the transverse colon and rectum, respectively. This case is considered to be highly associated with genetic factors. Long-term and careful surveillance is mandatory for early detection of recurrent or additional tumors.

Adenocarcinoma↗
PubMed1984

Lipid peroxidation as a possible cause of benzoyl peroxide toxicity in rabbit dental pulp--a microsomal lipid peroxidation in vitro.

The toxicity of composite resin on rabbit dental pulp was investigated biochemically. A microsomal fraction of rabbit dental pulp was incubated with each of the components of composite resins, and the formation of peroxide was determined by the thiobarbituric acid reaction. Benzoyl peroxide (BPO), the most widely used catalyst, was the most effective on peroxidation, but monomers were not. Cations such as Cu2+ or Fe2+ were required for acceleration of this reaction. Authentic polyunsaturated fatty acids and phospholipids were extensively converted into their peroxides by BPO, but amino acids and carbohydrates were not. Among the active oxygens, hydroxyl radicals were thought to be responsible for BPO-dependent peroxidation. The results presented in this paper indicate that the lipid portion of the cells may be attacked by hydroxyl radicals produced by BPO and copper or iron. Therefore, BPO is considered to be the major factor responsible for the toxicity of composite resins.

Animals↗
PubMed1978

[Apicoectomy].

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Adult↗