Biomedical subjects
Publications and source records attributed to T Okuno.
The vestibular function test in the guinea pig consists of spontaneous nystagmus recording, positional test and caloric test. If clip electrodes are used, recording of nystagmus in the guinea pig is successful. It takes less than 30 min to complete the whole test, and the animal tolerates the procedure without any complication.
Utricular maculae of guinea pigs were irradiated by argon laser through the oval window without touching the perilymph. The stapes was replaced in the oval window after irradiation. The inner ear was studied morphologically and physiologically. Argon laser beam caused detachment of the sensory epithelium from the basement membrane of the utricular macula. The lesion was round and localized at the site of irradiation. The epithelium changed to a layer of cuboidal cells after 2 to 3 weeks at the irradiated spot. Degeneration of the epithelium gradually spread to the periphery, and total loss of sensory epithelium was observed 10 weeks after irradiation. Hearing was preserved, and caloric test showed normal response.
This paper describes the feasibility of labyrinthectomy of only the vestibular part using argon laser in humans. In animal experiments, the utricular and saccular maculae were completely destroyed using argon laser with the otoprobe of the HGM system via the oval window, following stapedectomy. The human utricular and saccular maculae can be approached in a similar manner. Several approaches to the nerves and ampullae of the anterior and lateral semicircular canals are discussed. The most appropriate method to abolish the function of the ampullae is to sever the ampullary nerves. This can be done through the widened oval window with the argon laser otoprobe. After laser application, the oval window is covered by a piece of perichondrium. A stapes prosthesis is placed on the long process of the incus. Laser singular neurectomy may be used to sever the nerve to the posterior ampulla.
A case of malignant fibrous histiocytoma (MFH) of the urinary bladder was presented. A 59-year-old man visited our hospital with a chief complaint of gross hematuria with clots. Intravenous urography revealed a filling defect on the left side of the bladder. CT scan demonstrated that the tumor invaded the bladder wall deeply. The histology of the biopsy specimens obtained by TUR was suspected to be transitional cell carcinoma. Bleeding from the bladder was so severe that a lot of units of blood transfusion were required in order to compensate for anemia before total cystectomy was performed. The tumor was hemispheric, moderately demarcated, measuring 5.5 cm x 4.0 cm x 5.5 cm, and located at the posterior wall. The histological diagnosis was malignant fibrous histiocytoma, inflammatory type, with venous invasion of tumor cells. Postoperatively, the patient received 5 courses of combination chemotherapy of adriamycin (100 mg/body, day 1) and dacarbazine (400 mg/body, day 1-5). He is alive with no evidence of local and metastatic disease 24 months after operation, in spite of the poor prognosis predicted from the histological findings. MFH of the urinary bladder is very rare. We also made a brief review of prior reports on this disease.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Histochemical changes in peptidergic and catecholaminergic neurons during ischemia were investigated in the cerebral neocortex of the gerbil. Catecholaminergic fibers were observed by catecholamine histofluorescence with glyoxylic acid solution, and peptidergic neuron systems such as vasoactive intestinal polypeptide (VIP), somatostatin (SOM), and neuropeptide Y (NPY) were observed by immunohistochemistry. Two hours after unilateral occlusion of the internal carotid artery, catecholaminergic fibers disappeared in the neocortex on the occlusion side, while peptidergic nerve fibers except for NPY fibers were intact after 2 hours of ischemia. NPY fibers had decreased in number on the occlusion side 2 hours after ischemia. VIP-, SOM-, and NPY-immunoreactive neurons showed a decrease of 60% six hours after ischemia, and these neurons completely disappeared in the cerebral neocortex 24 hours after ischemia. These results suggest that catecholaminergic neuron system is more vulnerable than the peptidergic one in ischemic event.
We have evaluated the problem of autoantibodies such as antinuclear antibodies (ANA), smooth muscle antibody (SMA) and antibodies to thyroid microsomal (TMA) and to thyroglobulin (TGA) related to interferon therapy in 27 patients with chronic hepatitis B. Anti-interferon antibody was also studied by Western blot method. Eight patients had ANA and 2 had SMA during interferon therapy. However, 6 of the 8 patients were ANA positive and one of the 2 was SMA positive prior to interferon treatment. No patients developed TMA, TGA or anti-interferon antibody. Eight (29.6%) of the 27 patients had clearance of both DNA polymerase and HBeAg and persistent normalization in alanine aminotransferase levels with interferon therapy. Seven of the 8 responders developed none of the autoantibodies related to interferon therapy. These results suggest that the presence of ANA or SMA during treatment may affect the therapeutic response to interferon.
Single photon emission tomography (SPECT) using Tc-99m-d,1-hexamethylpropylenamine oxime (HMPAO) was performed in two children with epileptic disorders during both sleeping and waking diurnal stages. Immediate postictal and interictal SPECT scans were obtained for a child with partial epilepsy. They demonstrated an interictal decrease in the regional cerebral blood flow (rCBF) and a more remarkable immediately postictal decrease in rCBF. The focus was in the same region of the SPECT for both interictal and postictal spikes. Another patient was diagnosed as having continuous spike-waves during slow sleep without epileptic seizures. Although SPECT during wakefulness showed no asymmetry, SPECT during sleep revealed decreased rCBF at the same location as the predominant area of diffuse epileptic discharges. We conclude that HMPAO SPECT is useful in investigation of the etiological mechanisms of seizures and epileptic discharges in epileptic disorders in childhood.
To identify the focus of paroxysmal neuronal activity causing epilepsy in tuberous sclerosis (TS), the regional cerebral blood flow (r-CBF) in 19 patients with TS was assessed using single-photon emission computed tomography (SPECT) with I-123 iodoamphetamine (IMP), in correlation with serial interictal EEGs and organic changes observed on magnetic resonance imaging (MRI). There was a general irregularity of cortical IMP uptake and retention in TS, and two-thirds of the cerebral regions exhibiting high intensity in T2-weighted MRI images (cortical tubers) showed a decrease in r-CBF. In addition to in tubers, decreased r-CBF was observed in regions in which MRI was considered to indicate destruction of the normal cortex, atrophy or vascular abnormalities, although these areas did not consistently show epileptic changes in serial EEGs. Among the cortical regions which consistently showed epileptic foci in serial EEGs, none showed abnormal r-CBF without lesions on MRI. We conclude that IMP-SPECT is useful for visualizing the epileptogenic laterality in cases with bilateral MRI lesions and EEG epileptic changes, and to differentiate epileptogenic foci from electrophysiological propagated areas. However, regarding the severity of epilepsy, the MRI findings showed a better correlation than the IMP-SPECT findings did.
We developed a polymerase chain reaction assay for the direct detection of hepatitis B virus in paraffin-embedded liver tissue and applied this assay to determine whether hepatitis B virus DNA exists in livers with chronic hepatitis non-A, non-B. Fifty five liver biopsy samples were studied: 11 from patients with HBeAg-positive chronic hepatitis (paraffin-embedded) and 44 from patients with chronic hepatitis non-A, non-B (21 paraffin-embedded; 25 fresh frozen). Thirty three (75%) of the non-A, non-B cases were positive for hepatitis C virus antibodies. Approximately 1 to 10 ng of DNA was extracted from the paraffin-embedded tissue and amplified using oligonucleotide (23-mer) primers specific for the S gene (positions 261 to 692). The beta-globin gene was used as an internal control for sensitivity because this is a single copy gene and allows for relative quantification. In each of the chronic hepatitis B livers, the expected 432-base-pair amplification product for hepatitis B virus DNA and beta-globin gene product were both detected. On the other hand, in the 21 paraffin-embedded chronic hepatitis non-A, non-B livers, no hepatitis B virus DNA was detected, although beta-globin gene was observed in all. Furthermore, in all 25 frozen non-A, non-B livers, beta-globin gene was observed, but no hepatitis B virus band was seen. The limit of detection of hepatitis B virus DNA by this method was estimated to be one genomic copy of hepatitis B virus DNA per cell.(ABSTRACT TRUNCATED AT 250 WORDS)
Neurons in the hippocampus and striatum are vulnerable to the ischemic insult. In the present study we focused on the vulnerability of acetylcholine (ACh)-containing neurons in the striatum. To determine the change of ACh content in the striatum, we employed a simple sensitive brain microdialysis method with high performance liquid chromatography electrochemical detection. Morphological change of cholinergic neurons was studied by ACh-esterase staining during ischemic insult. After bilateral carotid artery occlusion, local cerebral flow decreased less than 5 ml/min/100 g in the striatum. Ach content in dialysate for 20 min after the occlusion was elevated to 135% of the control. ACh content decreased to 15% of the control 2hs after the ischemia. Density of Cholinergic fibers and cell bodies was reduced 10 min after the ischemia and further decreased 20 min after the occlusion. Our study suggests that the transient elevation of ACh content was probably due to diffusion of ACh from destruction cholinergic terminals after the ischemic insult. The increase of ACh immediately after arterial occlusion may affect severity of ischemic damage in the brain by its excitatory effect.
The 60 cases of primary renal pelvic and ureteral tumors treated at Mie University hospitals between January 1977 and December 1987 were reviewed and factors predicting the prognosis were investigated. The patients consisted of 47 men and 13 women (3.6: 1.0). Their ages ranged from 38 to 82 years with a mean of 65.2 years. According to Akaza's category classification of the ureteropelvic tumor, 42 cases were classified to category A, 15 cases category B and 1 case was classified to category C. Histologically, 59 transitional cell carcinomas and 1 squamous cell carcinoma were found. As to grading, 5 was G1, 31 G2, 21 G3 and 2 GX. As to staging, 20 were pT1, 10 pT2, 21 pT3, 3 pT4 and 6 pTX. Staging was correlated well with grading. Total nephroureterectomy with bladder cuff was performed on 39 patients and the other surgical treatments were done on 15 patients. Recurrence of the bladder tumor was found in 22.4%. The 5-year survival rate (Kaplan-Meier's method) was 47.8% for all of the patients. Among the patients with transitional cell carcinoma, the 5-year survival rate was 100% for G1, 57.6% for G2 and 28.6% for G3. As to staging the 5-year survival rate was 90.0% for below pT1, 20.0% for pT2 and 41.1% for pT3. The results from the present study suggest the prognosis is decided by grade and stage in pelvic and ureteral tumors, and it is wanted to develop a system of postoperative adjuvant therapy.
Thirty patients with bone metastasis were treated with eel calcitonin (CT) to relieve severe pain from metastatic bone lesions. Patients were two males and twenty-eight females with a mean age of 52.8. CT was administered intramuscularly in twenty-seven patients and intravenously in three. CT was effective on 55.6% of patients to reduce severe bone pain but did not decrease the amount of analgesics in most patients. Serum Ca and P were not changed markedly. As side-effects, two patients complained of nausea and vomiting after administration of CT but they weren't severe. These results indicate that CT is quite useful drug for relief of severe bone pain from metastatic lesions in patients with breast or digestive tract carcinomas.
Six temporal bones obtained from four individuals with Alagille's syndrome, aged 4 months and 3, 6, and 7 years, were studied histopathologically. The external auditory canals and tympanic membranes were normal. Although the stapes, the interossicular joints, and the subarcuate fossae were slightly underdeveloped in the majority of cases, the other structures in the middle ear were almost normal. However, severe anomalies were observed in structures in the inner ear. In all cases, both the bony and membranous structures of the posterior semicircular canal were partially or totally absent, and, in three ears, those of the anterior semicircular canal were also partially absent; the lateral semicircular canal, however, was normal in all cases. The cochlea was observed to be shortened in only one case.
Osteomas of the middle ear are rare. We report a case of a 7-year-old boy with osteoma originating from the pyramidal eminence, combined with congenital cholesteatoma. The osteoma and cholesteatoma were successfully removed by tympanomastoidectomy. The long process of the incus and the superstructure of the stapes disappeared. The body of the incus was sculpted and used as a columella. Histopathologically, the osteoma was much the same as an external auditory canal osteoma. The possibility of a primary congenital origin of this neoplasm is suggested.
Urinary bile acids from 20 patients treated with chenodeoxycholate, 18 treated with ursodeoxycholate, 15 treated with rifampicin and 8 patients with advanced cirrhosis were analyzed by gas-liquid chromatography and gas-liquid chromatography-mass spectrometry. Occurrence rates and amounts of three so-called unusual trihydroxy bile acids, hyocholate, ursocholate and omega-muricholate, were increased in patients treated with chenodeoxycholate, ursodeoxycholate or rifampicin and decreased in cirrhotic patients as compared with those in untreated healthy adults. These data suggest that chenodeoxycholate and ursodeoxycholate are hydroxylated to produce unusual trihydroxy bile acids in bile acid-loaded humans and that this metabolism may be related to the induction of hepatic microsomal enzymes by rifampicin. In contrast, the hydroxylation of chenodeoxycholate and ursodeoxycholate may be impaired by severe hepatic damage. Because the urine is a secretory pathway for internal bile acids, the occurrence of unusual trihydroxy bile acids in the urine may be used as an indicator of hepatic ability to metabolize "hydrophobic" dihydroxy bile acids to their secretory forms.
Explore the source record for details and available documents.