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T Takata

Publications and source records attributed to T Takata.

At least 73 records · Page 4Linked to original sources
PubMed1999

Clinical and histopathological analyses of desmoplastic ameloblastoma.

Desmoplastic ameloblastoma (DA) is an unusual subtype of ameloblastoma characterized by pronounced desmoplastic stroma. There is, however, still argument whether DA is a distinct clinicopathologic entity. To enhance knowledge of DA, 7 cases of DA (7.9%) were retrieved from 89 ameloblastomas field in the Department of Oral Pathology, Hiroshima University School of Dentistry and analyzed clinicopathologically and histopathologically. The mean age of the patients with DA and non-DA at the time of the diagnosis was 40.6 +/- 5.9 years and 33.1 +/- 2.0 years, respectively. The male-to-female ratio was 2.5:1 in DA and 1.8:1 in non-DA. Four (57%) DAs were located in the maxilla where only 6% of the non-DA occurred. Interestingly, all DAs arose in the anterior/premolar area of the jaws and 6 cases were located mainly within the alveolus. None of the DA showed typical radiographic features of ameloblastoma. In 5 DAs, scattered radiopacities were observed in the radiolucent lesion and gave preoperative diagnoses of non-ameloblastomatous lesions or even osteosarcoma. All DAs showed pronounced desmoplastic stroma where there were compressed tumor islands usually lacking a peripheral layer of ameloblastic cells and a central zone of stellate reticulum. There was cystic change within the epithelial nests in 3 DAs and true glandular structures with mucus cells in a case of DA. Tumor islands often infiltrated into marrow spaces of surrounding bone. There was no capsule formation. Recurrence rate was 14% in DA and 20% in non-DA. The present study based on data of DA in the Japanese population supports that DA must be considered as a distinct clinicopathologic entity.

Adolescent↗
PubMed1999

A new quadruple therapy for Helicobacter pylori: influence of resistant strains on treatment outcome.

BACKGROUND: There have been no reports concerning the efficacy and safety of a 1-week quadruple therapy regimen of omeprazole, amoxycillin, roxithromycin and metronidazole for Helicobacter pylori infections and the impact of primary resistance on the eradication rate. METHODS: One hundred and sixty-nine consecutive patients with peptic ulcer disease as well as gastritis with biopsy-proven H. pylori infection were entered into an open study of omeprazole 20 mg o.m., amoxycillin 500 mg t.d.s., roxithromycin 150 mg b.d., and metronidazole 250 mg t.d.s. Helicobacter pylori status was determined by urease test, histology and culture. Susceptibility to amoxycillin, metronidazole and roxithromycin was determined by the E-test. RESULTS: H. pylori was eradicated in 155 out of 169 (92%; 95% CI 88-96%) by intention-to-treat analysis, and in 155 out of 163 (95%; 95% CI 92-98%) by per protocol analysis. The prevalence of primary resistance against amoxycillin, roxithromycin and metronidazole was 2 out of 166 (1%), 16 out of 166 (10%) and 27 out of 166 (16%), respectively. H. pylori was eradicated in 25 out of 27 (93%) patients with metronidazole-resistant strains compared with 130 out of 136 (96%) in patients with metronidazole-sensitive strains of H. pylori. It was eradicated in 15 out of 16 (94%) patients with roxithromycin-resistant strains while in 140 out of 147 (95%) patients with roxithromycin-sensitive strains of H. pylori, and in two out of two (100%) patients with amoxycillin-resistant stains compared with 153 out of 161 (95%) in patients with amoxycillin-sensitive strains. H. pylori was eradicated in three out of four (75%) patients with double resistance against metronidazole and roxithromycin compared with 152 out of 159 (96%) patients with sensitive strains to metronidazole and or roxithromycin. None of these differences were statistically significant. Severe side-effects were found in only one out of 169 patients-anaphylaxis due to penicillin. CONCLUSIONS: The 1-week quadruple therapy with omeprazole, amoxycillin, metronidazole and roxithromycin was found to eradicate H. pylori in over 90% of all patients. This regimen was also found to be beneficial for patients with pre-treatment resistant strains to metronidazole, roxithromycin or amoxycillin, and was observed to be safe and well-tolerated.

Adult↗
PubMed1999

So-called 'hybrid' lesion of desmoplastic and conventional ameloblastoma: report of a case and review of the literature.

So-called 'hybrid' lesion of ameloblastoma, which is composed of desmoplastic ameloblastoma and conventional follicular/plexiform ameloblastoma, is an unusual variant of ameloblastoma and only eight cases of 'hybrid' lesion have been published in the English literature. To enhance knowledge of this interesting tumor, we add a case of 'hybrid' lesion that occurred in the right mandible of a 48-year-old Japanese male. Radiographic examination disclosed a honeycomb appearance at the anterior alveolar region, combined with a unicystic radiolucency in the molar region of the mandibular body. Histologically, the former showed microscopic features of desmoplastic ameloblastoma and the latter those of follicular ameloblastoma with focal granular cell transformation. The lesion was enucleated with curettage of surrounding bone and the lesional cavity was marsupialized. Although tumor tissues reappeared at 3, 5, 7 and 14 months after the surgery, the patient has remained disease free for 11 years after the last vaporization by CO2 laser of the recurred tumor. Many more cases of 'hybrid' lesion are needed to clarify the clinicopathological, histopathological and biological characteristics of this interesting variant of ameloblastoma.

Ameloblastoma↗
PubMed1999

Lambert-Eaton myasthenic syndrome associated with idiopathic thrombocytopenic purpura and diffuse panbronchiolitis: long-term remission after a course of intravenous immunoglobulin combined with low-dose prednisolone.

We report a case of Lambert-Eaton myasthenic syndrome (LEMS) associated with idiopathic thrombocytopenic purpura (ITP) and diffuse panbronchiolitis (DPB). An extensive search for malignancy yielded negative results. Interestingly, ITP and DPB developed simultaneously when the patient suffered from myasthenic symptoms. This is the first report in the Japanese or English literature of an association of LEMS, ITP, and DPB. The use of cholinesterase blocker alone did not improve the myasthenic symptoms, and the symptoms and signs relapsed with the tapering of prednisolone (PSL) dosage. However, after administration of immunoglobulin (IVIG) (0.4 g/kg/day x 5 days), low-dose PSL (20 mg/day) alleviated the LEMS and ITP, and the diseases have remained in remission for 8 months without additional IVIG. We suspect that there is a synergistic relationship between IVIG and PSL.

Anti-Inflammatory Agents↗
PubMed1999

Immunohistochemical evaluation of the small and large proteoglycans in pleomorphic adenoma of salivary glands.

This study investigated the immunolocalization of small and large proteoglycans (PGs), including decorin, biglycan, PG-M/versican and aggrecan, in salivary pleomorphic adenoma (PA) using monoclonal and polyclonal antibodies. In addition, a polyclonal antibody, A0082, recognizing blood vessels was also used to help identify truly mesenchymal tissues in PA. Decorin reactivity was detected only in tumor capsule and interstitial tissue of non-neoplastic salivary gland, but not in the tumor tissue. Biglycan was frequently revealed throughout the matrix of small chondroid regions and in the peripheral portion of larger chondroid regions. PG-M/versican was mainly localized to the truly mesenchymal tissues in PA and the innermost portion of tumor capsule. On the contrary, aggrecan was extensively expressed in the non-luminal epithelial areas as well as in the myxoid and chondroid areas, but not in the truly mesenchymal tissues. These findings suggest that aggrecan is the most widely distributed PG in PA and may be produced mainly by non-luminal tumor cells. The absence of aggrecan from the truly mesenchymal tissues argues against its origin from this source. Both aggrecan and biglycan may play important roles in the chondroid differentiation and morphogenesis of PA.

Adenoma, Pleomorphic↗
PubMed1999

Odontogenic ghost cell carcinoma: report of four new cases and review of the literature.

Only 12 odontogenic ghost cell carcinomas (OGCC) have been reported in the English language literature to date. This article reports four additional cases of this rare odontogenic tumour and examines them in relation to those previously described. Judging from the number of published cases, the OGCC is more prevalent in Asians than other racial groups, occurs more often in the maxilla than the mandible, and is slightly more common in males than females. Histologically, elements of a benign calcifying odontogenic cyst (COC) can be identified in all the malignant variants, either separated or admixed with the malignant epithelial component. The latter can consist of either small basaloid cells or large epithelial cells. Despite the differing histological presentations, the biological behavior of the tumour is unpredictable, with some cases characterized by relatively indolent growth and others by a locally aggressive and potentially fatal course. The tumour apparently arises most often from malignant transformation of a preexisting benign COC, although it may also develop from other odontogenic tumours.

Adult↗
PubMed1999

Biosynthesis of glycosaminoglycans and aggrecan by tumor cells in salivary pleomorphic adenoma: ultrastructural evidence.

The present study attempted to discover the sites of synthesis of various glycosaminoglycans (GAGs) and aggrecan in salivary pleomorphic adenoma (PA) with the use of a highly sensitive and specific post-embedding immunogold-silver staining technique at the ultrastructural level. Silver particles representing various GAGs and aggrecan were found to accumulate frequently in the intercellular spaces of non-luminal cells in the epithelial clusters and were dispersed in the myxoid matrix of the mesenchyme-like areas. Furthermore, the non-luminal epithelial cells were demonstrated to contain immunopositive intracytoplasmic vesicles and vacuoles, some of which were of Golgi complex origin. In contrast, intracellular silver particles for hyaluronic acid were mostly attached to the inner surface of the cell membrane. These observations agree well with the current theories of the biosynthesis of GAGs and proteoglycans and provide direct evidence for the production of various GAGs and aggrecan by tumor epithelial cells of PA. Such findings support the ideas that in PA a loss of epithelium occurs by stromalization following epithelial secretion of extracellular matrix substances and transformation of epithelium to mesenchyme represents the basic principle of the tissue heterogeneity in this tumor.

Adenoma, Pleomorphic↗
PubMed1999

Prognostic significance of apoptotic index in completely resected non-small-cell lung cancer.

PURPOSE: To evaluate the significance of apoptotic index (AI) as a prognostic factor after surgery for non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: A total of 236 patients who underwent surgery for previously untreated pathologic stage I to IIIa NSCLC between 1985 and 1990 were reviewed. AI was defined as the number of apoptotic cells, detected by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end-labeling, per 1,000 tumor cells. Proliferative index (PI) and aberrant p53 expression were also evaluated immunohistochemically. RESULTS: The 5-year survival rate for the lowest-AI group (AI < 5.0) was 74.7%; those for the lower-AI group (5.0 < or = AI < 11.0) and the higher-AI group (11.0 < or = AI < 25.0) were 51.6% and 57.8%, respectively. These survival rates were significantly lower than that of the lowest-AI group (P =.021 and P =.043, respectively). The highest-AI group (25.0 < or = AI), however, showed the most favorable prognosis, with a 5-year survival rate of 83.2%. Multivariate analysis confirmed that a moderate AI (5.0 < or = AI < 11.0 or 11.0 < or = AI < 25.0) was a significant factor to predict poor prognosis. The PIs for the lowest-, the lower-, the higher-, and the highest-AI groups were 32.3%, 48.0%, 54.3%, and 50.7%, respectively. The lowest-AI group showed a favorable prognosis because of its low PI, whereas the lower- and the higher-AI groups had a poor prognosis caused by increased cancer-cell proliferation. The highest-AI group showed the most favorable prognosis because apoptotic cell death overcame cell proliferation. No significant correlation was observed between AI and aberrant p53 expression. CONCLUSION: AI proved to be an independent prognostic factor in NSCLC.

Adenocarcinoma↗
PubMed1999

Periodontitis in the house musk shrew (Suncus murinus): a potential animal model for human periodontal disease.

BACKGROUND: Our understanding of periodontal diseases has been facilitated greatly by the use of animal models. However, no animal model has been identified that truly reflects the disease seen in humans. Suncus murinus, a rat-sized laboratory house musk shrew, has received attention as a valuable animal model due to ease of handling. In the studies described here, periodontal conditions in Suncus murinus were evaluated to determine the usefulness of the shrew as an experimental model for understanding various aspects of periodontal diseases. METHODS: Periodontal tissues of 34 Suncus murinus (18 to 430 days old) were examined macroscopically, morphometrically, histologically, and ultrastructurally. RESULTS: Dentition pattern is I3/1, C1/1, P2/1, M3/3. Spontaneous gingival swelling with accumulation of plaque was observed in more than two-thirds of animals older than 200 days. Morphometric analysis of alveolar bone demonstrated a pattern of bone loss that correlated closely with animal age. Histologically, periodontal lesions varying from gingivitis to periodontitis, similar to those observed in humans, were noted. Marked infiltration of lymphocytes and plasma cells in the connective tissue was noted, usually not seen in periodontal lesions of rodents. Although osteoclastic alveolar bone resorption was noted, active bone resorption was not a frequent feature in specimens obtained from chronic inflammatory lesions. Ultrastructurally, degradation of collagen fibers in the inflamed area and ingestion of collagen fibrils by fibroblasts in the deeper connective tissue were often seen. CONCLUSIONS: These results indicate the potential utility of Suncus murinus as a model to study periodontal disease; e.g., chronic nature of the inflammatory periodontal lesions, similar to those in humans, as well as other advantages including size and ease of handling and housing of these animals.

Age Factors↗
PubMed1999

The alteration of penicillin-binding proteins (PBPs) in drug-resistant Streptococcus pneumoniae isolated from acute otitis media.

Streptococcus pneumoniae is the micro-organism most frequently isolated from acute otitis media (AOM). Recently, drug-resistant or insensitive strains have been prevalent among pneumococcal AOM cases and were reportedly associated with persistent or recurrent otitis media. The purpose of this study was to examine the alterations of penicillin-binding proteins (PBPs) in Streptococcus pneumoniae isolated from AOM. The PBP samples from 21 clinically isolated strains were examined by 14C-penicillin binding assay and also by adding CCL and CDTR as competitors of 14C-penicillin. Reduced signals in PBP1A and PBP2X/2A were typically observed with the penicillin-resistant Streptococcus pneumoniae samples, while widely different PBP profiles were obtained in each strain of penicillin-insensitive Streptococcus pneumoniae. The competitive binding assay with penicillin-insensitive strains revealed the reduced affinity of CCL to PBPs in comparison with that of CDTR. The results of the penicillin-binding assay were consistent with the results from minimal inhibitory concentration analysis, and its potential usefulness for the prediction of drug resistance was demonstrated.

Acute Disease↗
PubMed1998

Reduced expression of cyclin-dependent kinase inhibitor p27Kip1 is an indicator of malignant behavior in oral squamous cell carcinoma.

BACKGROUND: Reduced expression of the cyclin-dependent kinase inhibitor p27Kip1 has been reported to correlate with poor survival in cohorts of breast and colorectal carcinoma patients. Posttranslational ubiquitin-mediated proteasomal proteolysis is related to p27Kip1 protein levels. However, to the authors' knowledge, no previous study has examined the expression of p27Kip1 in oral squamous cell carcinoma (OSCC). METHODS: To examine the expression of p27Kip1 and its clinicopathologic roles in OSCC, the authors studied the expression of p27Kip1 protein by immunohistochemistry in deparaffinized tissue sections of 20 normal oral mucosa specimens, 22 epithelial dysplasia specimens, and 70 OSCCs, and analyzed its correlation with clinicopathologic parameters. They also studied the expression of p27Kip1 mRNA and protein in six OSCC cell lines by Northern blot and Western blot analysis. To examine the mechanism of reduced expression of p27Kip1, OSCC cell lines were treated with the proteasome inhibitor LLnV. RESULTS: All the normal oral mucosa specimens and 73% (16 of 22) of the oral epithelial dysplasia specimens expressed p27Kip1 at high levels, whereas 87% of the OSCCs (61 of 70) showed reduced expression of p27Kip1. Furthermore, the levels of expression of this protein were significantly lower in carcinomas with metastasis than those without metastasis. Although OSCC cell lines expressed p27Kip1 mRNA at various levels, most of them expressed p27Kip1 protein at lower or undetectable levels. LLnV induced the expression of p27Kip1 protein in HSC2 cells, in which p27Kip1 protein was originally undetectable. CONCLUSIONS: These findings suggest that 1) reduced expression of p27Kip1 may correlate with the development and progression of OSCC and can be an indicator of malignant behavior of this neoplasm, and 2) increased proteasome-mediated degradation may play an important role in the reduction of p27Kip1 protein expression.

Adult↗
PubMed1998

Three-dimensional appearance of Langerhans cells in human gingival epithelium as revealed by confocal laser scanning microscopy.

Detailed three-dimensional morphological information of the cell without distortion due to thin sectioning can be obtained from thick sections using a confocal laser scanning microscope. Here that microscope was used to evaluate human gingival Langerhans cells stained with anti-CD1a antibody. Optical sectioning and reconstruction by laser scanning microscopy revealed not only three-dimensional aspects of Langerhans cells but also spatial information on the distribution of their dendritic processes towards the gingival surface. The orientated configuration of those processes may reflect the reaction of the gingival Langerhans cell to the surrounding moist environment containing antigenic stimuli originating in saliva.

Antibodies↗
PubMed1998

Odontogenic tumors. A demographic study of 759 cases in a Chinese population.

Seven hundred fifty-nine cases of odontogenic tumors retrieved from the files of College of Stomatology, West China University of Medical Sciences were classified according to the World Health Organization's Histological Classification of Odontogenic Tumors and compared with similar reports from other countries. Among these cases, 93.9% of the tumors were benign and 6.1% were malignant. Ameloblastomas predominated (58.6%) with a predilection for the mandible, while odontomas, generally regarded as the most frequent odontogenic tumor in North America, only accounted for 6.7%, the fourth most common tumor in this series. The mandible and the maxilla were divided into eight anatomic regions, and the distribution of each odontogenic tumor type amongst these regions was recorded. The relative incidence of each tumor type, patient age and gender were also compared with data from other selected large series. Geographic differences were noted in the relative incidence of ameloblastoma, odontoma and malignant odontogenic tumors among the Chinese/African, North American and Turkish/German groups. Ameloblastoma and malignant odontogenic tumors are not considered rare in a Chinese population.

Adolescent↗
PubMed1998

Proliferative activity of calcifying odontogenic cysts as evaluated by proliferating cell nuclear antigen labeling index.

The calcifying odontogenic cyst (COC) presents with diverse histological features; thus, several subclassifications have been proposed. To evaluate the significance of the various histological features and subtypes of COC from the perspective of proliferative activity, the proliferating cell nuclear antigen (PCNA) labeling index (LI; the percentage of positive nuclei) was assessed immunohistochemically in 25 cases of COC (21 benign and four malignant). All of the benign cases were of the cystic variety and further subclassified into non-proliferative subtype (NPS; four cases); proliferative subtype (PS; eight cases); and COC associated with odontoma (COCaO, nine cases). The PCNA LI of the malignant COC (65.2+/-5.6) was significantly higher than that of the benign COC (11.6+/-9.0; P = 0.002). Non-proliferative subtype (6.8+/-2.8) showed the lowest PCNA LI and PS (17.2+/-11.2) the highest of among the three subtypes of benign cystic COC (P = 0.028). In nine cases of COCaO, six showed epithelial lining of the non-proliferative type as NPS and the other three had lining with proliferative features as PS. The PCNA LI of the latter COCaO group (14.3+/-6.6) was significantly higher than that of the former (6.1+/-4.3; P = 0.05), as seen between PS and NPS. These results demonstrate that PCNA LI is a possible parameter for differentiating malignant COC from benign COC and, whatever the subtypes, the proliferative features in the lining are the main factor influencing the proliferating activity of COC.

Cell Division↗
PubMed1998

Analysis of the expression of CagA and VacA and the vacuolating activity in 167 isolates from patients with either peptic ulcers or non-ulcer dyspepsia.

OBJECTIVES: The goals of this study were: 1) to examine the prevalence of cytotoxin-associated protein (CagA), vacuolating cytotoxin (VacA), and the vacuolating cytotoxin activity (VCA) in vitro of infecting Helicobacter pylori isolates and 2) to clarify the relation between the expression of these virulence factors and the occurrence of peptic ulceration. METHODS: One hundred sixty-seven clinical isolates of H. pylori from patients with peptic ulcer disease (gastric ulcer, 62 cases; duodenal ulcer, 48 cases) and nonulcer dyspepsia (57 cases) were studied regarding their genetic and phenotypic properties. RESULTS: Type 1 bacteria, which had both CagA and VCA, and type 2 bacteria, which did not express either CagA or VCA, represented 62.9% and 7.8%, respectively; the remaining 29.4% had an intermediate phenotype, expressing either CagA independent of the presence of VCA (CagA+VCA-) or vice versa (CagA-VCA+). CagA+VCA- and CagA-VCA+ bacteria represented 17.4 % and 12.0%, respectively, both of which were more numerous than the type 2 category. The proportion of the CagA-positive isolates was significantly higher in both the duodenal ulcer (97.9%) and gastric ulcer (83.9%) patients than in the non-ulcer dyspepsia patients (61.4%) (p < 0.01). On the other hand, the proportion of VacA/VCA-positive isolates was not significantly different between peptic ulcer disease and non-ulcer dyspepsia. CONCLUSIONS: The currently used classification of this bacterium based on the concomitant expression of CagA and VacA/VCA into the two major types is not adequate. The CagA-positive phenotype thus may be important as a virulence marker for peptic ulcer disease independent of the presence of VacA/VCA.

Adult↗