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T Kubo

Publications and source records attributed to T Kubo.

At least 523 records · Page 29Linked to original sources
PubMed1995

High-resolution MRI of the human cochlea.

The majority of magnetic resonance imaging (MRI) studies in neurotology concern the evaluation of retrocochlear pathologies or temporal bone lesions. Recently, quite a number of investigators have attempted to use imaging diagnosis to obtain a diagnosis and manifest the pathological findings of Meniere's disease. However, there is no evidence that endolymphatic hydrops in patients with Meniere's disease can be identified by imaging techniques. In this study we could depict Reissner's membrane clearer than before with the use of image processing. At the present time, we cannot apply the 2.11T MRI machine to patients under FDA regulation. We believe that MRI diagnoses of endolymphatic hydrops and small lesions of the internal structures of the inner ear will be possible in the near future.

Adult↗
PubMed1995

Glutamate receptor gene family expressed in vestibular Scarpa's ganglion of rat.

The expression of glutamate receptor gene family in the vestibular Scarpa's ganglion (VG) of rat was determined using molecular biological techniques including reverse transcription (RT), polymerase chain reaction (PCR), amplification, DNA sequencing, and immunocytochemistry. Oligonucleotide primers were designed from the previously cloned sequences of the AMPA-selective glutamate receptors (GluR1-4), KA-selective glutamate receptors (GluR5-7, KA1&2), NMDA-selective glutamate receptors (NMDAR1&2), and metabotropic glutamate receptors (mGluR1-4). The cDNAs synthesized from the VG mRNAs were amplified with the specific primers for the subunits of each glutamate receptor gene family. Analysis of the nucleotide sequences of the amplified cDNAs identified the expression of GluR1-4, GluR5, and NMDAR1 in the VG. Sequence analysis identified the expression of all the four subunits of GluR1-4 in two alternative spliced versions named "flip" and "flop" in the VG. In an immunocytochemical study, a large number of VG neurons showed only GluR2/3-like immunoreactivity (IR) while GluR1- or GluR4-IR could not be determined in the VG. The present study suggested that the subunits of GluR1-4, GluR5, and NMDAR1 may be assembled into the hetero-oligomeric glutamate receptor complex in the VG and that the VG neuron-specific stoichiometry of the receptor complex may be functionally significant for the afferent signal transduction in the rat peripheral vestibular system.

Animals↗
PubMed1995

Vestibular modulation of the septo-hippocampal cholinergic system of rats.

Effects of vestibular stimulation on the in vivo release of hypothalamic histamine and hippocampal acetylcholine (ACh) were investigated in urethan-anesthetized rats, using a brain microdialysis method. Changes in glutamate concentration in the medial vestibular nucleus (MVN) were also monitored by a microbiosensor technique using a glutamate oxidase-embodied platinum electrode. Caloric stimulation with hot water increased the glutamate release in the MVN, while that with ice water decreased it. It is evidenced that glutamate is a neurotransmitter between afferent vestibular nerve and the MVN. Electrical stimulation of the round window evoked the release of hypothalamic histamine and hippocampal ACh and these effects were inhibited by the blockade of second-order vestibular neurons by the pre-injection of 6,7-dinitroquinoxaline-2,3-dione (DNQX), an antagonist of non-N-methyl-D-aspartate (non-NMDA) glutamate receptors, into the ipsilateral vestibular nucleus. Caloric stimulation with both hot and ice water increased the release of hypothalamic histamine and hippocampal ACh. It is suggested that both the histaminergic and cholinergic systems were activated by the imbalance of intervestibular activities. Depletion of neuronal histamine by alpha-fluorometylhistidine (FMH), an irreversible inhibitor of histamine synthesis, did not suppress the vestibular evoked release of hippocampal ACh. In contrast, caloric stimulation did not evoke hypothalamic histamine release in rats treated with ethylcholine aziridiniun ion (AF64A), a putative cholinotoxin. All these findings suggest that the vestibular information activated the histaminergic neurons via the activation of the cholinergic neurons and this neuronal circuit was involved in the vestibulo-autonomic response.

Acetylcholine↗
PubMed1995

Changes in Fos and Jun expression in the rat brainstem in the process of vestibular compensation.

By means of immunohistochemical technique, we examined the changes in Fos and Jun expression after unilateral labyrinthectomy (UL) in the rat brainstem. We observed Fos-like immunoreactivity (-LIR) in the ipsilateral medial vestibular nucleus (ipsi-MVe), the contralateral prepositus hypoglossal nucleus (contra-PrH) and the contralateral inferior olive beta subnucleus (contra-IOb) 1 h after UL. Then, Fos expression in the contra-PrH and the contra-IOb disappeared 3 days after surgery. However, we still found the residual expression in the ipsi-MVe, which disappeared within 7 days. On the other hand, no Jun-LIR was detected in the vestibular or vestibular-related nuclei before or after the operation. Fos expression in the MVe, PrH and IOb was induced immediately after UL. Then, the Fos expression disappeared in accordance with the development of the vestibular compensation. These findings suggest that the transient Fos expression in the vestibular and vestibular related nuclei is a trigger of vestibular compensation.

Animals↗
PubMed1995

Assessment of auditory and vestibular functions after vestibular neurectomy for Menière's disease.

Fourteen patients (12 Meniere's disease, one delayed endolymphatic hydrops and one labyrinthitis) suffering from intractable vertigo were treated with retrosigmoid vestibular neurectomy (RSVN) in our institute. Dizziness was controlled completely in all patients. Hearing was preserved in 91.7% of the cases with pure tone threshold deteriorating by more than 10 dB in one case, remained unchanged in 10 cases and improved in one case during long term observation. Substantial decrease of tinnitus was observed in 78.6%. Vestibular compensation was chronologically analyzed with a stabilometer, ENG and vestibular rotation test (0.01-0.64 Hz). Vestibular compensation under static conditions was accomplished within 2 weeks, except for spontaneous nystagmus measured in the dark. Asymmetry of vestibulo-ocular reflex was noted 2 weeks after the operation but had disappeared after 4 weeks. However, for over 2 years the VOR time constant remained lower (4.3-5.2 s) than the pre-operative value (8.2 s). Electro-cochleogram (ECoG) was recorded before and after RSVN. The -SP/AP ratio tended to increase after RSVN in the operated ear, though there was no change in the contralateral ear. The efferent olivo-cochlear bundle was thought to play a potential role in this increase of the -SP/AP ratio.

Adult↗
PubMed1995

[Multivariate analysis of everyday handicap of patients with dizziness].

A preliminary questionnaire consisting of 30 questions was developed to evaluate handicaps in everyday life for 105 patients with dizziness. Factor analysis divided the questions into 5 principal factors of handicap due to dizziness: 1) disturbance of social activity, 2) body motion precipitating dizziness, 3) limitation of physical activity, 4) emotional disturbance, and 5) disturbance of interpersonal communications. The score of each factor was calculated as the sum of the scores of three principal questions in the corresponding factor. There was no contribution of clinical diagnosis, patient's age or gender, or duration of the disease to the score of each factor. Thus, it is concluded that the reorganized questionnaire which consists of three principal questions in 5 factors can be used for evaluating dizziness handicaps in everyday life. The score of the emotional factor in patients with Meniere's disease was higher than that for other vestibular disease. The score of the body motion factor in patients with vestibular neuronitis was higher than that for vertebro-basilar artery insufficiency. Thus, the re-organized questionnaire can also be used for evaluating the contribution of each factor to dizziness handicaps in everyday life.

Activities of Daily Living↗
PubMed1995

[Diagnostic and therapeutic problems in vestibular neuronitis: clinical implications for sudden vertigo].

We defined sudden vertigo as a sudden, unilateral peripheral vestibular dysfunction. The criterion for its diagnosis is a single episode of vertigo without cochlear and central symptoms. Among 20 patients with sudden vertigo there was no difference in clinical aspects between those with CP (canal paresis) (CP% > or = 25%) and those without CP (CP% < 25%). This suggests that sudden vertigo with CP is due to sudden vestibular dysfunction with predominant involvement of the lateral semicircular canal. Basically, vestibular neuronitis is considered to be due to acute unilateral neuropathy of the vestibular nerve. However, since we have no routine examination for evaluating vestibular nerve function, sudden vertigo with CP should be diagnosed as vestibular neuronitis. We then assessed the prognosis of sudden vertigo with CP (vestibular neuronitis). About two years after the onset of CP 4 of 10 patients had recovered. However, patients with persistent CP had a handicap in their everyday life because of the dizziness induced by head movements. The possibility of recovery of vestibular function in response to steroid therapy may improve the prognosis in vestibular neuronitis.

Adult↗
PubMed1995

[Analysis of familial aggregation of ovarian and breast cancer in patients with ovarian cancer].

In 118 patients with common epithelial ovarian tumors (carcinomas and tumors of borderline malignancy) treated at Tsukuba University Hospital and Tsukuba-Gakuen Hospital, family histories of ovarian and breast cancer were obtained from medical records or in interviews, and familial aggregation of these cancers was examined. 1. A positive family history was found in 10 patients (8.5%). The high incidences of familial ovarian cancer and ovarian cancer in patients who were previously affected with breast cancer were statistically significant. 2. Patients with serous adenocarcinoma showed a significantly greater rate of positive family history than those with mucinous adenocarcinoma. 3. No significant correlation was seen between the clinical stage and a positive family history. 4. Every patient except one with a positive family history had onset of ovarian cancer after menopause. The age at onset for familial ovarian cancer cases was younger than that for the patients' relatives who were affected previously. 5. There were 14 healthy women considered to be at high risk for ovarian cancer among 5 familial ovarian and 2 familial ovarian and breast cancer aggregations. These preliminary findings suggest that screening for early ovarian cancer should be conducted in high risk relatives of familial cancer patients and women affected with breast cancer previously. More detailed studies are needed to define the occurrence of familial or hereditary ovarian and breast cancers in Japan.

Adenocarcinoma, Mucinous↗
PubMed1995

[An immunohistological study on expression of glutathione S-transferase pi (form) in human ovarian carcinoma].

Specimens from 102 cases of ovarian cancer were stained immunohistochemically with a rabbit polyclonal antibody prepared against the placental form of the enzyme glutathione S-transferase (GST-pi). All 28 cases of mucinous adenocarcinoma, 19 of clear cell carcinoma and 4 of malignant transformed dermoid cysts were stained positively with the GST-pi antibody. These tumors are considered to be resistant to chemotherapeutic agents as compared with other epithelial tumors. With regard to the histological grade, the degree of staining was reduced according to the loss of differentiation. An investigation of the relationship between GST-pi stain and the prognosis of the 50 patients with stage 2,3 or 4, according to the Kaplan-Meier method, revealed that the prognosis improved as the staining decreased. In conclusion, results suggested that immunohistochemical staining of GST-pi is correlated with the chemoresistance of the tumor, and may predict the outcome in patients with ovarian cancer.

Adenocarcinoma, Clear Cell↗
PubMed1995

[Acute pulmonary embolism after radical operation for renal cell carcinoma with vena caval extension: a case cured by thrombolytic therapy].

A 54-year-old man was hospitalized for a right renal tumor with intraluminal extension into the vena cava. He underwent radical nephrectomy with thrombectomy and regional lymphadenectomy. On the 8th postoperative day, he suddenly complained of dyspnea with tachypnea and cyanosis. Arterial blood gas analyses under an oxygen flow of 4L/min revealed PaO2 32.1 mmHg. Pulmonary angiography revealed filling defects in the right main pulmonary artery and left descending branch. Under the diagnosis of acute pulmonary embolism, thrombolytic and anti-coagulation therapy was performed and the patient recovered from the disease. We should be aware of pulmonary embolism as a postoperative complication of urological surgery.

Acute Disease↗
PubMed1995

[Correlation between malignancy of gastric cancer and c-myc DNA amplification or overexpression of c-myc protein].

The amplification of c-myc DNA for fresh frozen tissue of 31 gastric adenocarcinomas was examined with dot blot hybridization method. Using the avidin-biotin peroxidase complex method, the expression of c-myc protein was examined immunohistochemically for formalin-fixed paraffin embedded tissue of 51 gastric adenocarcinomas including the same cases for c-myc DNA analysis. c-myc DNA amplification was detected in only 4 cases (12.9%). However, c-myc protein overexpression was recognized in 21 cases (41.2%). Only one of 4 cases showing c-myc DNA amplification indicated overexpression of c-myc protein. There was no statistically significant relation of c-myc protein overexpression with clinicopathological factors (histology, depth of invasion, invasion of the vessels, metastasis, intraabdominal dissemination and histological staging). These results suggest overexpression of c-myc protein could be recognized even in early gastric cancer indicating the relation of this gene product with proliferation of gastric cancer cells, although its role in the progression and metastasis of gastric adenocarcinoma might be minimal.

Adenocarcinoma↗
PubMed1995

The presence and subtype of Epstein-Barr virus in B and T cell lymphomas of the sino-nasal region from the Osaka and Okinawa districts of Japan.

BACKGROUND: Association between Epstein-Barr virus (EBV) and human malignancies, including sino-nasal lymphoma (SNL), has been suggested. EBV-associated malignancies have been reported to show distinct geographic distribution. EXPERIMENTAL DESIGN: In the present study, the presence of an EBV genome and its subtypes (type A and B) were examined in 52 cases of sino-nasal lymphomas of B and T cell type collected from two areas of Japan: Osaka, situated on the mainland, and Okinawa, islands situated in a southwest part of Japan with a subtropical climate. Our previous epidemiologic study showed that the frequency of nasal T cell lymphoma was 3.5 times higher in Okinawa than in Osaka. RESULTS: There were no prominent differences in age distribution or sex ratio between these two areas: age ranged 8 to 85 (median 54) years, with a male to female ratio of 1.26:1. Immunophenotypically, 27 cases were B cell type (20 Osaka, 7 Okinawa), 20 were T cell type (9 Osaka, 11 Okinawa), and 5 were undefined. By PCR, EBV positivity in throat washings of normal individuals in Osaka and Okinawa was 52 and 53%, respectively, with marked preponderance of subtype A in both areas. EBV genome was found in 6 of 15 cases (40%) and 4 of 5 cases (80%) of nasal B and T cell lymphomas in Osaka and in 3 of 7 cases (43%) and 7 of 7 cases (100%) in Okinawa, showing the different frequencies of positivity by immunophenotype but not by district. All but one patient had type A EBV. The in situ hybridization confirmed the results of PCR as positive signals in the nucleus of proliferating cells. Latent membrane protein-1 was expressed in 13 of 22 cases (59%). CONCLUSIONS: These findings suggest that EBV, exclusively type A, might be a causative factor in sino-nasal lymphoma of not only T cell but also B cell type in Japan.

Adolescent↗
PubMed1995

Angiotensin-converting enzyme inhibitor-induced anemia and treatment for erythrocytosis in renal transplant recipients.

Erythrocytosis is not rare in renal transplant recipients, and phlebotomy is still the main treatment. Recently, the occurrence of angiotensin-converting enzyme (ACE) inhibitor induced anemia in patients on chronic hemodialysis and in renal transplant recipients has been reported. We herein report 5 transplant recipients whose hematocrit levels decreased while taking ACE inhibitors, including 2 patients treated with ACE inhibitors for erythrocytosis. The individual mean hematocrit values ranged from 35.0% to 54.7% before treatment and from 27.6% to 42.0% after treatment. The hematocrit level in the 2 patients with erythrocytosis decreased from 54.7% to 39.8% and 47.5% to 27.6%, respectively. Anemia improved after discontinuation or dosage reduction of the drugs. The patients were given the same immunosuppressive drugs, and had good renal function. ACE inhibitor-induced conspicuous anemia was not observed in the transplant recipient who received a kidney from a twin sibling and had not been taking any immunosuppressive drugs, nor in the 8 other patients with diabetes mellitus or chronic glomerulonephritis who served as controls. We conclude that ACE inhibitor-induced anemia may frequently arise in an immunosuppressed state. Based on these events, the ACE inhibitor can be used as a potent drug for erythrocytosis in post-transplant recipients.

Adult↗
PubMed1995

[Intrascrotal epidermal cyst: a case report].

A 37-year-old male visited our hospital complaining of right scrotal mass formation. An elastic hard, fist-size mass was found in the right scrotum. Under the diagnosis of an intrascrotal benign tumor, the mass was removed. The tumor had no relation to the testis or epididymis. The surgical specimen weighted 220 g and measured 13 x 8 x 8 cm in size. Histopathological diagnosis was epidermal cyst of the intrascrotum. Epidermal cyst of the intrascrotum is a rare disease and only 13 cases have been previously reported in Japan.

Adult↗
PubMed1995

[Rupture of an external iliac artery aneurysm into the bladder: a case report and review of the literature].

A case of fatal hemorrhage caused by rupture of the external iliac artery aneurysm into the urinary bladder is presented. The patient, a 58-year-old Japanese female, had undergone total hysterectomy, and post-operative therapeutic radiation, for uterine cancer in 1974. A vesicocecal fistula was observed, and surgical intervention for closure was performed in May, 1992. On July, 13, 1992, she presented with pulsating hemorrhage from the urinary bladder. Angiography was consistent with rupture into the bladder of an iliac artery aneurysm. Surgical intervention for closure of the aneurysm was performed but the aneurysm could not be resected. She had relapse of the fistula which became infected with methicillin-resistant Staphylococcus aureus (MR-SA), and died 3 months postoperatively. To the best of our knowledge, there have been only 3 cases in which an iliac artery aneurysm ruptured directly into the urinary bladder. This case indicates that resection of the aneurysm for therapy is a vital requirement.

Adult↗
PubMed1995

[Establishment of a new scirrhous gastric cancer cell line OCUM-2M from a primary gastric tumor].

We report on the establishment and characterization of a scirrhous gastric cancer cell line, designated OCUM-2M, derived from a 49-year-old Japanese female. OCUM-2M was derived from a primary tumor of stomach taken by total gastrectomy. The cell line grew singly or in clusters in the cultured medium. The cell line continued to multiply for more than one year. Doubling time was 37.3 hours, chromosomal mode was 70. The DNA ploidy pattern was aneuploid and DNA index was 1.59. It produced several tumor-associated antigens such as CEA, CA19-9, SLX and SPan-1. The cell line was transplantable in athymic BALB/c nude mice, and histological findings of the xenografted tumor showed poorly differentiated adenocarcinoma. The growth of OCUM-2M was stimulated following the addition of EGF, b-FGF and KGF, and decreased following the addition of TGF-beta 1. This cell line is useful in vitro and in vivo systems for studies of the biology of scirrhous gastric carcinoma.

Adenocarcinoma, Scirrhous↗