Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Yuji Imate is active.

Publication


Featured researches published by Yuji Imate.


Acta Oto-laryngologica | 1993

Vestibular Neuronitis: Epidemiological Survey by Questionnaire in Japan

Toru Sekitani; Yuji Imate; Takaaki Noguchi; Tetsuhiko Inokuma

An epidemiological survey on vestibular neuronitis in Japan was conducted by means of a questionnaire filled in by major neuro-otology clinics (otolaryngologists) during 1988-1990 (3 years). The diagnostic criteria of vestibular neuronitis settled on in 1986 by the Standardization Committee of the Japan Society of Equilibrium Research were applied. Gross analysis of questionnaire answers showed that i) there was no sexual difference, ii) the peak of age distribution was between 40-50 years, iii) about 30% of all cases had had common colds prior to the disease, the rate being highest among children below 10 years, iv) disappearance of positional and positioning nystagmus appeared in about 60% of all cases within 3 months, and that v) caloric CP was observed in about half of the cases at the follow-up test. Progress was not as favorable when compared to previous studies.


Cytometry | 2000

Relationship between cytogenetic aberrations by CGH coupled with tissue microdissection and DNA ploidy by laser scanning cytometry in head and neck squamous cell carcinoma

Yoko Hashimoto; Atsunori Oga; Kenji Okami; Yuji Imate; Yuji Yamashita

BACKGROUND The relationship between DNA sequence copy number aberrations (DSCNAs) and DNA ploidy in head and neck squamous cell carcinomas (HNSCCs) is still controversial. Materials and Methods We analyzed DSCNAs by comparative genomic hybridization (CGH) combined with microdissection and DNA ploidy by laser scanning cytometry (LSC) in 18 surgically removed HNSCCs and compared the data. RESULTS Copy number increases were most frequently observed on chromosomes 3q (16 cases), 8q (13 cases), and 12p (11 cases). Copy number decreases were observed on chromosome 3p (14 cases). LSC revealed DNA aneuploidy in 10 of the 18 cases. All DNA aneuploid tumors exhibited gain or amplification of DNA copy number at 12p11-12.1, whereas gain of DNA copy number was found in only 1 of 8 diploid tumors. DSCNAs were more frequent in DNA aneuploid tumors than in diploid tumors (P < 0.005). CONCLUSIONS The present observations indicate a close relationship between DSCNAs and DNA ploidy in HNSCCs.


Cancer Genetics and Cytogenetics | 2001

Amplification of 3q26∼qter correlates with tumor progression in head and neck squamous cell carcinomas

Yoko Hashimoto; Atsunori Oga; Shigeto Kawauchi; Tomoko Furuya; Norio Shimizu; Tomoko Nakano; Yuji Imate; Hiroshi Yamashita

Biological characteristics of malignant tumors including head and neck squamous cell carcinoma (HNSCC) are greatly affected by genetic alterations. However, the relationship between chromosomal aberrations and pathologic tumor stage in HNSCC has not been elucidated. In 32 patients, DNA sequence copy number aberrations (DSCNA) were surveyed by comparative genomic hybridization (CGH) combined with a microdissection method. The average number of DSCNA was 15.3 per tumor and increased with tumor stage (P<.05). DNA copy number gain was detected at 3q26 approximately qter in 29 tumors (91%), and 13 of these tumors displayed marked DNA amplification. Tumor stage was linked with this amplification (P<.05). The increase in DSCNA and amplification of 3q26 approximately qter are likely to be useful markers for estimating tumor progression in HNSCC.


Acta Oto-laryngologica | 1993

Vestibular Compensation in Vestibular Neuronitis. Long-term Follow-up Evaluation

Yuji Imate; Toru Sekitani

We evaluated vestibular function, especially for positional, head shaking and caloric nystagmus, in 43 patients with vestibular neuronitis, for long periods from the onset. The results suggested that in these cases of vestibular neuronitis, which were studied for more than 10 years after onset of the disease, the disease may still be in the uncompensated stage or may have worsened in the partially compensated stage.


Operations Research Letters | 2000

Epithelial-Myoepithelial Carcinoma of the Nasopharynx

Yuji Imate; Hiroshi Yamashita; Shiro Endo; Kenji Okami; Tomomi Kamada; Masahiro Takahashi; Hiroo Kawano

We present a patient with a rare epithelial-myoepithelial carcinoma of the nasopharynx with a typical biphasic histopathologic pattern. Immunohistochemical findings support the concept that the inner cells differentiate to ductal epithelium and the outer cells to myoepithelium. In this patient complete excision of the tumor and reconstruction with a pedicled sternocleidomastoid myocutaneous flap were performed. A DNA diploid pattern from flow cytometric study indicates a favorable prognosis. There was no recurrence nor metastasis for 55 months.


Acta Oto-laryngologica | 1993

Vestibular neuronitis in children.

Tetsuya Tahara; Toru Sekitani; Yuji Imate; Keiko Kanesada; Mayuri Okami

Seventeen cases of vestibular neuronitis in children, including 11 cases from the questionnaires of an epidemiological survey in Japan and 6 patients in our clinic, were examined. Sex and age distribution was 11 males and 6 females, ranging in age from 3 to 15 years. Bilateral and recurrent cases were not encountered. Fifty-three percent of children had had a preceding episode of an upper respiratory tract infection and this ratio was higher than that in adults. The etiology of vestibular neuronitis is probably many-faceted, but it is thought that upper respiratory tract infections play an important role especially in children. Vertiginous symptoms had almost subsided among children at the last visit. However, among adults, 24% of patients felt persisting unsteadiness. The disappearance of positional and positioning nystagmus was observed in 71% of children at the last visit. Caloric CP failed to recover in only 14% of all cases who were re-examined. As shown in this study, the prognosis in children is better than in adults for nystagmus and caloric response. The results of this study thus indicate that not only central compensation but also recovery of the peripheral vestibular function is more effective for bringing recovery from the vestibular disorder in children than in adults.


Molecular Carcinogenesis | 2006

Interaction of OGG1 Ser326Cys polymorphism with cigarette smoking in head and neck squamous cell carcinoma.

Tomoko Hashimoto; Kenichiro Uchida; Naoko Okayama; Yuji Imate; Yutaka Suehiro; Yuichiro Hamanaka; Yoshiya Ueyama; Hiroshi Yamashita; Yuji Hinoda

Recent molecular epidemiological studies have demonstrated that the human oxoguanine glycosylase 1 (OGG1) gene polymorphism may be associated with various cancers. To determine whether the OGG1 Ser326Cys polymorphism interacts with clinicopathological parameters including smoking and alcohol intake in head and neck squamous cell carcinoma (HNSCC), DNA samples from 192 patients with primary HNSCC were genotyped and studied by the case‐only design. We observed an association between the Cys/Cys genotype and HNSCC with cigarette smoking of more than 40 pack‐years by a multivariate logistic regression analysis (OR = 8.10, 95% CI = 1.06–61.73). No significant association of this genotype with alcohol intake was observed. Our present data suggest a possible interaction between the OGG1 Ser326Cys polymorphism and smoking in HNSCC.


Tumor Biology | 2006

ALDH2 1510 G/A (Glu487Lys) polymorphism interaction with age in head and neck squamous cell carcinoma.

Tomoko Hashimoto; Kenichiro Uchida; Naoko Okayama; Yuji Imate; Yutaka Suehiro; Yoshiya Ueyama; Hiroshi Yamashita; Yuji Hinoda

Recent molecular epidemiological studies have revealed a possible association of the acetaldehyde dehydrogenase-2 (ALDH2) 1510 G/A (Glu487Lys) polymorphism with various cancers including head and neck squamous cell carcinoma (HNSCC). To further elucidate the significance of this polymorphism in HNSCC development, the relationship between ALDH2 1510 G/A and clinicopathological parameters, cigarette smoking or alcohol intake was evaluated in patients with HNSCC. DNA samples from 192 patients with primary HNSCC and 192 age- and gender-matched healthy controls were genotyped and statistically evaluated. Although there was no significant difference in the genotype distribution of ALDH2 1510 G/A between cases and controls, we found that the frequency of the ALDH2 genotypes with the mutated A (Lys) allele was greater in patients aged <66 years than in those aged ≧66 years (p = 0.034). This tendency became more evident in patients with the habit of drinking (n = 143; p = 0.009). The association of ALDH2 1510 G/A with age remained significant after multivariate logistic regression analysis was performed for the patients (odds ratio for an age interval for 1 year, 0.970; 95% confidence interval, 0.943–0.998). The present data suggest a possible interaction between the ALDH2 1510 G/A polymorphism and age in HNSCC.


Acta Oto-laryngologica | 1993

Vestibular Neuronitis in Aged Patients: Results from an Epidemiological Survey by Questionnaire in Japan

Hirotaka Hara; Toru Sekitani; Yuji Imate; Tetsuhiko Inokuma; Yoshiko Okuzono; Keiko Nishikawa

An epidemiological survey of vestibular neuronitis in Japan was done using a questionnaire. Answer sheets were obtained from 619 patients with vestibular neuronitis. In order to evaluate data from aged patients, 74 cases were singled out. The following results were obtained: i) There was no sexual difference and no laterality of affected side; ii) There was no case of bilateral vestibular neuronitis; iii) Ten cases were reported as recurrent. Aged patients had a relatively high rate of recurrence; iv) About 10% of 74 cases had had an upper respiratory tract infection, and this rate was lower than that for patients under 65 years of age; v) Thirty-five cases had complications. Hypertension was the most common complication; vi) The caloric test was re-used in 28 cases. The continued existence of caloric CP was observed in 23 cases upon re-examination.


Acta Oto-laryngologica | 1995

Central Disorders in Vestibular Neuronitis

Yuji Imate; Toru Sekitani; Ma Yuri Okami; Masako Mjura

Between 1972 and 1993 equilibrium and audiological examinations were made on 73 patients who had been diagnosed to suffer from vestibular neuronitis. In 23 of these patients, central nervous disorders (CND) were suspected from the result of tests of positional and positioning nystagmus, smooth pursuit, optokinetic nystagmus or auditory brainstem response. In this group of patients the frequency of associated disorders and vertiginous symptoms (dizziness) was statistically higher than in the remainder 50 patients who did not have CND. In the CND group the time interval between the onset and improvement or disappearance of all vertiginous symptoms, nystagmus and canal paresis was longer than in the non-CND group.

Collaboration


Dive into the Yuji Imate's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge