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Biomedical subjects

M Okamoto

Publications and source records attributed to M Okamoto.

At least 469 records · Page 26Linked to original sources
PubMed1996

Basophilic deposits on the cupula: preliminary findings describing the problems involved in studies regarding the incidence of basophilic deposits on the cupula.

In this study, the possibility of whether basophilic deposits adhered to the cupulas in the semicircular canals was investigated histologically. Results indicated that basophilic deposits were present in all three cupulas of the semicircular canals. The overall incidence of basophilic deposits in the superior, lateral and posterior semicircular canal cupulas was 26%, 41% and 37%, respectively. The incidence of basophilic deposits bound to the cupulas increased with age. The possible origin of these basophilic deposits on the cupulas and the increased incidence of basophilic deposits with increasing age are discussed.

Adult↗
PubMed1996

Influence of vestibular organ stimulation on stomach movement and respiration.

Some previous investigators have reported controversial results in the stomach movement in response to labyrinthine stimulation (1). The purpose of the present study was to investigate the influence of vestibular stimulation on the stomach movement and respiration in anesthetized cats, and to investigate the differences between increased and decreased responses of the stomach movement. This study used an electrophysiological technique: a bipolar stainless-steel stimulating electrode with a tip diameter of 20 microns introduced chronically into the anterior and/or lateral semicircular canal (2). The intragastric pressure was recorded by using a balloon-transducer system. Respiration was recorded by measurement of the thorax. When the peripheral labyrinth was stimulated, we found conflicting results in that the pressure in the stomach increased several times and sometimes decreased. Respiration usually became irregular or intensified. It seems that forced respiration may be involved in vestibular vomiting but we were unable to induce vomiting.

Animals↗
PubMed1996

Vestibular training for acute unilateral vestibular disturbances: its efficacy in comparison with antivertigo drug.

We carried out a clinical trial on the treatment of acute unilateral vestibular disturbances (AUVD) without typical Meniere's disease and benign paroxysmal positional vertigo. Two therapy groups were selected: vestibular training (VT) with drug therapy and drug administration alone. After the experimental period of 8 weeks, all patients were classified into two groups depending on the methods of treatment, and the clinical courses of the patients were compared statistically. It was confirmed statistically by global judgments of symptoms and signs that improvement rates were higher in the group treated by VT with medication than the improvement rate in the group with medication alone. It is concluded that VT is effective for early relief from vestibular ataxia.

Adult↗
PubMed1996

Optokinetic after-nystagmus in the human: a comparative study between normals and patients with peripheral vestibular and central disorders.

The purpose of this study was to classify various patterns of optokinetic after-nystagmus (OKAN) appearing in normal subjects, and to investigate the difference of OKAN between 147 normal subjects and 55 patients suffering from central nervous system (CNS) or peripheral vestibular disorders, in which 18 CNS disorders and 37 peripheral vestibular diseases were included. Data was divided into three categories by duration of the 1st phase of OKAN, i.e. hypo-response below 10 sec, middle response between 10 and 60 sec and hyper-response above 60 sec. The patterns of OKAN were then classified into six types with nine subtypes according to the following classification. All combinations of duration times of the 1st phase of OKAN toward both directions were then classified into six types, i.e. type 1, bilateral middle responses; type 2, bilateral hyper-responses; type 3, bilateral hypo-responses; type 4, unilateral hypo-response with contralateral middle response; type 5, unilateral hypo-response with contralateral hyper-response; and type 6, unilateral middle response with contralateral hyper-response. Moreover, subtypes "a" and "b" indicated symmetric and asymmetric in both types 1 and 2. Namely, if a relative value of the difference between bilateral responses against the sum of those was less than 20%, it was called "symmetric", otherwise, "asymmetric". Type 3 was divided into two subtypes: no response (3a) and hypo-response (3b). Results were summarized as follows. All combinations of horizontal OKAN toward both sides appeared in the 147 normal subjects. The incidence of each type, i.e. 1a, 1b, 2a, 2b, 3a plus 3b, 4, 5 and 6, was 10.9, 15.0, 2.7%, 1.4%, 25.2%, 31.3%, 4.1% and 9.5%, respectively. The incidence of type 3, type 3a in particular, was higher in patients than in the normals (p < 0.001). Also, the incidence of type 4 in normals was significantly higher than that of the patients (p < 0.01). Caloric tests revealed unilateral and bilateral canal pareses (CP) in 44 of 52 patients. The incidence of type 3 in the group of patients with CNS disorders was higher than those with peripheral vestibular disorders (p < 0.01). The 2nd phase of OKAN appeared in only nine of the 147 normals and in nine of the 55 patients. However, the 3rd phase of OKAN was observed in only one patient, the duration of which was 80 sec. The appearance rate of the 2nd phase of OKAN in patients was significantly higher than in the normal subjects (p < 0.05).

Adult↗
PubMed1996

Hearing recovery and its process from the time of onset in sudden deafness.

A total of 547 patients with idiopathic sudden hearing loss were divided into eight groups according to the days (1-8 days) of their initial visit after onset, and initial hearing thresholds, hearing recovery and its process were investigated. There were no significant differences in initial hearing thresholds and hearing recovery among the eight groups. However, a difference was noticeable in the distribution of the thresholds at the initial visit and that on the 7th day between groups 1, 2 and 7. Many cases showed rapid recovery in groups 1, 2 and 7. We speculate that the treatment influenced the hearing recovery process in patients who showed relatively rapid recovery.

Deafness↗
PubMed1996

Idiopathic bilateral sensorineural hearing loss: its clinical study in cases with rapidly progressed deafness.

In a series of 127 patients with idiopathic bilateral sensorineural hearing loss (IBSH) at the Hearing Clinic in the Department of Otolaryngology, Kitasato University Hospital, 20 cases showed rapid progression of hearing impairment. These patients had been treated with the same therapeutic regimen used in sudden deafness (SD). Improvement of hearing loss after treatment was generally less effective in the cases with rapidly progressed IBSH than in the cases with SD. However, hearing improvement was achieved in some cases with rapidly progressed IBSH when the treatment had started in the early stages after the onset of rapidly progressive hearing loss.

Adolescent↗
PubMed1996

Effectiveness of fibronectin in myringoplasty using temporal fascia.

A study of myringoplasty with temporal fascia homograft employing fibronectin was conducted in 14 ears in which the same myringoplasty procedure without fibronectin (1-5 times) had failed to afford closure of tympanic membrane perforation. Closure was obtained in eight ears. These results suggest that fibronectin is effective in myringoplasty using treated temporal fascia homograft.

Adult↗
PubMed1996

Cephalometric analysis in patients with obstructive sleep apnea syndrome.

Cephalometry is useful as a screening test for anatomical abnormalities in patients having obstructive sleep apnea syndrome. In this study, various conventional parameters in cephalometry, such as the distance and angles determining the oropharyngeal space, and the areas of the soft palate, oral cavity, tongue and pharynx in both posterior-anterior and lateral view X-ray films, were measured before and after surgery in order to evaluate the preoperative predictability and usefulness of uvulopalato-pharyngoplasty and/or midline laser glossectomy (MLG) for the purpose of preoperative assessment and evaluation of surgical treatment. As test subjects, American adult patients with disturbed respiration in sleep observed at Oakland Otology and Apnea Clinic during 1989-1992 and Japanese patients with the same problems observed at Kitasato Univ. Hospital during 1992-1994 were used. The results were as follows: i) cephalometry revealed morphological abnormalities in the skull, and the measurement of soft tissue in the oropharynx provided useful anatomical data to assess the space of the upper airway in each patient before operation; ii) the areas of the soft palate, the whole tongue and the lower half of the tongue were significantly enlarged, and the lengths of MPH, SPL and PNS-H were longer in the apnea group than in the snoring group; iii) in MLG patients, increases in the area of the oral cavity and pharyngeal cavities and a decrease in the area of the upper half of the tongue were observed.

Adult↗
PubMed1996

Combined chemotherapy and radiation therapy in head and neck cancer.

A combination chemotherapy (PT treatment) with cisplatin and tetrahydropyranyl-adriamycin (THP-ADM) was performed in 17 patients with head and neck squamous cell carcinoma. Chemotherapy treatment began with an intravenous dose of 50 mg/body cisplatin and an intravenous dose of 20 mg/body THP-ADM. Administration of THP-adriamycin was performed on the first day only, while cisplatin treatment was repeated once a day until the third day. Five of the 17 cases achieved complete response (29.4%) and seven achieved partial response. Response rate was 70.6%. Toxicity was mild and controlled with symptomatic treatment. Leukopenia was observed in 71.4% thrombocytopenia 14.3% (due to myelosuppression), appetite loss 38.1%, general fatigue 28.6% and nausea and vomiting 23.8%. No electrocardiographic abnormality was noted.

Antineoplastic Agents↗
PubMed1996

Combined therapy for hypopharyngeal cancer.

We studied 69 hypopharyngeal cancer patients who were treated between 1979 and 1992. The 5-year cumulative survival rate was 53%. There were five stage I, seven stage II, 20 stage III and 37 stage IV patients; survival rates for stages I, II, III, and IV were 80%, 54%, 61% and 47%, respectively. The 5-year survival rate for the 25 patients who received preoperative radiotherapy (fewer than 40 Gy) followed by total pharyngo-laryngo-esophagectomy was 59%. Forty-four patients received radical radiotherapy as a main treatment. From the standpoint of preserving vocal function, we recommend using the radical radiation as a first-choice treatment. The 5-year survival rate was 48%. There were 16 radiation failure patients after radical radiotherapy and two of them refused to have surgery. Fourteen patients (36%) received a salvage operation and the survival rate was 36%. The survival rate for the 30 patients who did not receive surgery was 61%; the patients who received surgery as a palliative purpose and the patients who refused to undergo surgery were included in this group. Both treatment regimens of the present study showed higher survival rates compared to the results of previous studies. We concluded that the improved results were due to the proper selection of the treatment, especially the attention given to the patient's immune response and the minimum death as a result of neck node metastasis.

Adult↗
PubMed1996

[Clinical studies on autologous blood transfusion].

To study the present status of blood transfusion in head and neck surgery, we investigated recent cases of intraoperative transfusion in our department. In addition, we present our autologous blood transfusion cases, presently involved in an ongoing clinical trial for patients with head and neck cancer in our department which began in 1989. 1. Investigation of intraoperative blood transfusion cases There were 37 cases of intraoperative blood transfusion among 677 cases who underwent surgery under general anesthesia during the period from May, 1991 to December, 1993. We divided these 37 cases into three groups according to the amount of intraoperative blood loss: less than 600ml (10 cases), more than 600ml and less than 1200ml (11 cases), and more than 1200ml (16 cases). Average amounts of intraoperative blood transfusion in each group were 195ml, 475ml and 780ml, respectively. As we noted that most of these 37 cases received a blood transfusion of less than 800ml, the majority needing intraoperative blood transfusion during head and neck surgery are potential candidates for autologous blood transfusion. Therefore, we have promoted autologous blood transfusion for intraoperative blood transfusion in head and neck surgery. Thus, the patients undergoing intraoperative autologous blood transfusion increased to seven annually as of 1994. 2. Clinical studies on autologous blood transfusion Among 677 cases of head and neck surgery conducted during a six year period (1989-1994), we experienced ten cases of autologous blood transfusion. For the prevention of anemia due to repeated blood withdrawal, we administered an iron preparation. Patients who preoperatively showed a low value of Hb (less than 11g/ dl) received intravenous drip infusion of erythropoietin. Since some patients selected for autologous blood transfusion, who also received neo-adjuvant chemotherapy and preoperative radiotherapy, exhibited a generally chronic anemia status, an iron preparation and erythropoietin should be preoperatively administered in combination.

Adolescent↗
PubMed1996

[Hearing acuity in the elderly in Japan].

In Japan, the elderly population has progressively increased. It is therefore expected that various social services for the elderly will be demanded. As most of the elderly have hearing impairment due to presbycusis, it is difficult to communicate smoothly with them. To provide the various social services, it is necessary to investigate hearing acuity in the elderly. Accordingly, the Hearing Research Group, which belongs to the Research Project on Aging and Health in the Ministry of Health and Welfare of Japan, investigated the hearing acuity of people 65 years old, or more. One thousand one hundred ninety two subjects were divided into five groups, Group A consisted of 170 males and 216 females between 65 and 69 years old, Group B, 186 males and 158 females between 70 and 74; Group C, 147 males and 140 females between 75 and 79; Group D, 63 males and 61 females between 80 and 84; and Group E, 29 males and 22 females 85 years old or more. We examined the 175 subjects 80 years old or more. Therefore, it is considered that this study could indicate the present condition of hearing acuity of the elderly of Japan. The average hearing levels measured at seven frequencies (125, 250 and 500Hz, and 1, 2, 4, and 8KHz) were 35.0dB in group A, 42.1 in group B, 46.1 in group C, 52.1 in group D, and 55.6 in group E. There were no differences in the average hearing level between males and females in any group. The audiogram pattern indicated a gradually descending curve in most subjects in all groups. The average speech discrimination rate was 75.4% in group A, 70% in group B, 63.8% in group C, 59.7% in group D, and 52.1% in group E. The percentage of subjects showing a short increment sensitivity index of more than 70% was 45.2% in group A, 49.3% in group B, 47.9% in group C, 51.6% in group D, and 59.7% in group D. In conclusion, hearing loss due to aging tended to be more progressive at higher frequencies while hearing acuity of frequencies covering normal speech was preserved. However, the speech discrimination rate decreased relative to changes in the pure tone hearing level. It was considered that the pathology of hearing loss due to aging begins with retrocochlear changes and cochlear factors are added to retrocochlear changes with aging.

Aged↗
PubMed1996

[Clinical studies of newly diagnosed prostate cancer].

BACKGROUND: The objective of this study is to report the outcome of various treatments in patients who were newly diagnosed prostate cancer from May 1984 to December 1994, at a single institution. METHODS: A retrospective study was carried out in the 142 patients. RESULTS: Total retropubic prostatectomy were performed in 52 patients (37%). The 5-year survival rates (Kaplan-Meier) in the patients with total prostatectomy were 89% in stage B (24), 86% in stage C (7), and 87% in stage D1 (17), respectively. Endocrine therapies (33) or endocrine therapies in combination with chemotherapies (37) as a initial therapy for stage D2 were performed. Among these therapies, endocrine therapy in combination with cyclophosphamide (700 mg/m2/4 weeks, i.v.) was superior to any of the other treatments in stage D2. The response rate, median response duration and median survival time in this combination therapy were 83%, 29 months and 49 months. The overall 3, 5, and 10-year survival rate in the 142 patients were 67%, 51% and 26%, respectively. The 5-year survival rates according to grade were 73% in grade 1, 45% in grade 2, 42% in grade 3, respectively. CONCLUSION: The 5-year survival rates in pathological stage C and D1 patients who received adjuvant hormone and radiation therapy after radical prostatectomy were 86% and 87%. The most effective therapy for stage D2 was hormone in combination with cyclophosphamide. The response rate and median response duration were 83% and 29 months.

Aged↗
PubMed1996

[Endothelin-1 levels in sputum and plasma of asthmatic patient after allergen provocation].

Recently, endothelin-1 (ET-1) has a potent of contractive effect to bronchial smooth muscle, and it suggests that ET-1 contributes to pathophysiology of bronchial asthma. To study the role of endothelin-1 (ET-1) in allergic asthma, we measured ET concentration in plasma and in sputum of nine allergic subjects following allergen provocation by using sandwich-enzyme immunoassay (EIA). ET-1 concentration in plasma were higher during IAR (2.31 +/- 0.24 pg/ml) (0.05 < p < 0.1) and LAR (2.55 +/- 0.27 pg/ml) (0.05 < p < 0.1) than prechallenge value (1.99 +/- 0.23 pg/ml) but there was no significant difference. On the other hand ET-1 concentration in sputum were significantly higher during IAR (14.75 +/- 2.77 pg/ml) (p < 0.05) and LAR (18.51 +/- 4.57 pg/ml) (p < 0.05) than prechallenge values (4.29 +/- 2.55 pg/ml). Thus these results suggest that ET-1 play a role of allergic bronchoconstraction (IAR and LAR) after allergen challenge.

Adolescent↗
PubMed1996

[Comparative studies on the time course of proliferating cell nuclear antigen and bromodeoxyuridine staining pattern in regenerating rat liver cells].

Immunohistochemical staining pattern of proliferating cell nuclear antigen (PCNA) was examined in regenerating rat liver specimens fixed under the various conditions (10% buffered formalin for 6hr, 1% paraformaldehyde for 6hr, 100% methanol for 4hr, 70% ethanol for 6hr). Time course of PCNA staining pattern after hepatectomy in the specimens fixed with 100% methanol or 70% ethanol coincided closely with that of bromodeoxyuridine (BrdU) staining pattern, which is known to be standard marker of cell proliferation. Similar result was obtained in fixation with 10% buffered formalin (10% BF) or 1% paraformaldehyde (1% PFA) when only granular staining pattern of PCNA was evaluated. These findings suggest that granular immunostaining of PCNA in tissue specimens fixed with 100% methanol, 70% ethanol, 10% BF or 1% PFA is useful for evaluating the extent of cell proliferation.

Animals↗
PubMed1996

[Five cases of hereditary high red cell membrane phosphatidylcholine hemolytic anemia in three families].

Five cases of hereditary high red cell membrane phosphatidylcholine hemolytic anemia in three families were described. All cases were clinically manifested by jaundice and splenomegaly. Hemolysis was evident from indirect hyperbilrubinemia, reticulocytosis and decrement of serum haptoglobin. Red blood cells showed morphological abnormalities such as poikylocytosis, anisocytosis and target cells on blood smears. Both direct and indirect Coombs' tests were negative. Ham test, sugar water test and hemoglobin electrophoresis showed no abnormalities. Osmotic fragility test showed decreased membrane fragility. Lipid analysis of red cell membrane showed increment of phosphatidylcholine content and decrement of sphingomyelin content, although plasma lipids were essentially normal. Influx and efflux of sodium through the red cell membrane were both increased. Splenectomy was performed without effect on one patient and the mother of other patients.

Adult↗