Biomedical subjects

T Okabe

Publications and source records attributed to T Okabe.

At least 235 records · Page 13Linked to original sources

PubMed1992

The synapsin I brain distribution in ischemia.

We examined the distribution of synapsin I in the gerbil brain and investigated ischemic damage of presynaptic terminals immunohistochemically by using this protein as a marker protein of synaptic vesicles. The reaction for synapsin I in normal gerbil brain is exclusively localized in the neuropil, and other brain structures such as neuronal soma, dendrites, axon bundles, glia and endothelial cells exhibited little immunoreactivity. In a reproducible gerbil model of unilateral cerebral ischemia, ischemic loss of synapsin I immunoreactivity in the affected hemisphere was confined to the area exhibiting overt infarction, where the breakdown of this protein was also confirmed by the immunoblot analysis, and noted much later than that of microtubule-associated protein 2 immunoreactivity, which was demonstrated in neuronal soma and dendrites. In the non-affected hemisphere, selective damage of presynaptic terminals due to Wallerian degeneration and subsequently occurring resynaptogenesis at the molecular layer of the dentate gyrus were clearly demonstrated as a loss and recovery of immunoreaction for synapsin I, respectively. In a gerbil model of bilateral cerebral ischemia, immunoreaction for synapsin I was persistently preserved after seven days to two months recirculation following a brief period of global forebrain ischemia in the CA1 region of the hippocampus, where delayed neuronal death was consistently observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1992

Production, purification, and characterization of botulinolysin, a thiol-activated hemolysin of Clostridium botulinum.

A hemolysin, botulinolysin, produced by Clostridium botulinum was purified to homogeneity and characterized. First, a strain of C. botulinum type C, strain C-203 Tox, which produced a large amount of hemolysin, was selected, and optimal culture medium and conditions for its production of hemolysin were determined. The hemolysin produced in the culture supernatant of this strain under optimal conditions was purified by a combination of ammonium sulfate precipitation, DEAE-Sepharose CL-6B column chromatography, Sephadex G-75 gel permeation chromatography, and SP-Toyopearl 650 M cation-exchange column chromatography, with a recovery of 12%. The purified hemolysin gave a single protein band in polyacrylamide gel electrophoresis (PAGE) with and without sodium dodecyl sulfate (SDS). The protein in this band in PAGE with SDS was estimated to have a molecular weight of 58,000 and was immunostained with a neutralizing monoclonal antibody. In PAGE without SDS, the hemolytic activity corresponded in position to the single protein band. The pI of the hemolysin was 8.4. Amino acid analysis of the purified hemolysin indicated the presence of four half-cystine residues per molecule. The purified hemolysin had a specific activity of 2,100 hemolytic units per microgram of protein on rabbit erythrocytes. It was activated by SH compounds, inhibited by cholesterol, and heat labile. The optimum pH for hemolysis was 6.0 to 7.0. Rabbit, human, and guinea pig erythrocytes were the most susceptible to the hemolysin, while sheep, mouse, rat, and chicken erythrocytes were much less susceptible. The purified hemolysin had a lethal effect in mice and was cytotoxic for some cultured cells: its 50% lethal dose in mice was 310 ng, and its 50% cytotoxic dose for Vero cells was 120 ng/ml.

Amino Acids↗

PubMed1992

Constitutive production of angiotensin converting enzyme from rheumatoid nodule cells under serum free conditions.

Angiotensin converting enzyme was assayed in serum free culture supernatants from unstimulated rheumatoid nodule cells. Angiotensin converting enzyme was released spontaneously and the angiotensin converting enzyme derived from rheumatoid nodule cells was suppressed in a dose and time dependent manner by the protein synthesis inhibitor cycloheximide. These data suggest the constitutive de novo synthesis of angiotensin converting enzyme by rheumatoid nodule cells.

Adult↗

PubMed1992

Effectiveness of oxide films in reducing mercury release from amalgams.

The release of mercury from four freshly-triturated amalgams into air, argon, and moist air environments was quantitated at three different temperatures. Although a measurable amount of mercury was released from dental amalgam, the evaporation rate was immediately reduced by several phenomena, the most important being the formation of an oxide film on the surface. This hypothesis was supported by the fact that release rates were elevated in an inert argon environment, but declined dramatically once air was introduced and oxidation could occur. The further amalgamation of "free" mercury, as well as the presence of water vapor, also contributed to the reduced release rates observed during aging. Mercury release was reduced to a negligible level within three to four hours after trituration. Only one of the amalgams, Tytin, demonstrated a thermal dependence for mercury release in air. The results of this study suggest that the exposure to mercury vapor from a freshly placed amalgam restoration would be negligible in consideration of the normal estimated daily intake from all other sources.

Air↗

PubMed1992

Induction of dyspnea by aerosol of endothelin-1/histamine or/methacholine in the conscious guinea pig.

The inhalation of aerosol of endothelin-1 (ET-1) induced dyspneal behavior in conscious guinea pigs pretreated with histamine or methacholine inhalation, although it was not observed by the inhalation of ET-1 alone. The dyspneal response to the inhalation of ET-1/histamine was potently inhibited by indomethacin, but it was not affected by nifedipine or diphenhydramine.

Administration, Inhalation↗

PubMed1992

Protective effect by cell-free antigen obtained from culture supernatant of phase I Bordetella bronchiseptica.

The cell-free antigen (CFA), with highly hemagglutination activity, obtained from the culture supernatant of Bordetella bronchiseptica was compounded with oil adjuvant to make a component vaccine (CFAV). In the immunization trial in mice, the offsprings whose mothers were immunized with CFAV escaped from death when challenged intrapleurally with virulent strain of B. bronchiseptica. The protective indices (difference of LD50 dose of the challenge strain between immunized and control groups) of the offsprings from CFAV-immunized mothers were over 3.0 in common logarithm value. Moreover, about 90% of the offsprings from CFAV-immunized mothers were negative in nasal turbinate atrophy, while over 80% of them from non-immunized mothers showed obvious turbinate atrophy when challenged intranasally with virulent strain. On the one hand, remarkable differences in the number of bacteria recovered from nostrils were observed between both test groups. It was concluded that CFAV is a very effective vaccine against B. bronchiseptica infection in animals.

Animals↗

PubMed1992

Protection from pseudorabies virus challenge in mice by a combination of purified gII, gIII and gVI antigens.

The antigens gII, gIII and gVI were purified from the lysates of the pseudorabies virus (PRV) -infected HmLu-1 cells using Sepharose 4 B coupled with MAbs against these antigens. Mice immunized with either gII, gIII, gVI antigen or a mixture of them were challenged intraperitoneally with 8.5 x 10(3) plaque forming units of PRV. All the mice immunized with 1.5 and 4.5 micrograms of the mixture and 4.5 micrograms of the gIII antigen survived. The sera of mice immunized with the mixture had virus neutralizing activity which was independent of complement, hemagglutination inhibition activity, and recognized major (93 kilodaltons) and minor (129, 74, 68 and 50 kilodaltons) PRV proteins under reducing conditions in western blotting. The serological activity levels in the lower survival group were not different from those in the complete survival. These results indicate that the mixture of each glycoprotein is more effective for eliciting of protective immunities in mice and that serological activity do not always correlate with protection.

Animals↗

PubMed1992

Pathological studies on local tissue reactions in guinea pigs and rats caused by four different adjuvants.

We investigated pathological changes at the injection site in guinea pigs and rats for 16 weeks following a single intramuscular injection of one of the following oil adjuvant emulsions; oil adjuvant ISA-70, Freund's incomplete adjuvant, Freund's complete adjuvant, and aluminium phosphate gel. In the animals injected with ISA-70 emulsion prepared by manual shaking, grossly, there was partial thickening of subcutaneous tissue, discoloration of inter-muscular connective tissue, and swelling of the inguinal lymph nodes at 2 and 4 weeks post injection (PI). Histopathologically, ISA-70 injected sites revealed acute inflammatory changes at 72 hrs PI, and peak reactions consisting of macrophage accumulation around oil cysts and fibrosis were observed at 4 weeks PI. These changes were less severe and of shorter duration than those in the other three adjuvants. Guinea pigs and rats injected with materials containing inactivated Newcastle disease virus (NDV) antigen similarly showed an infiltration of plasma cells and lymphocytes in addition to the changes described above. ISA-70 containing NDV antigen induced similar hemagglutination-inhibition titer to that induced by Freund's incomplete adjuvant.

Adjuvants, Immunologic↗

PubMed1992

Bond strengths of various materials to dentin using Amalgambond.

This study evaluated the bond strength of four restorative materials to dentin using Amalgambond. Two high-copper amalgams [Tytin; spherical, (T) and Epoque 80; lathe-cute, (E)], a gallium alloy [Gallium Alloy GF (G) and a resin composite [P-50 (P)] were tested. The polished dentin surface was treated with dentin-enamel activator (10 seconds), washed, dried, and adhesive agent was applied (30 seconds). In group A, the dentin adhesive was placed onto the dentin and while still wet, T, E, or G was condensed in cylinders (4 mm diameter) with condensation forces suggested by the manufacturer for a clinical situation. In group B, the cylindrical specimens of restorative material were allowed to set and then adhered to the treated dentin using the adhesive system. For the composite (control), the adhesive was applied to the treated dentin and while still wet, P was layered into the cylinder and cured for a total of 90 seconds. After storage in water (37 degrees C) for 24 hours, all the specimens were tested for tensile bond strength. This study revealed that the bond strength of P was significantly higher than the other materials tested and also that amalgam allowed to set for 1, 6 or 24 hours before adhesion to dentin had a significantly greater bond strength than freshly condensed amalgam. Although the desired high bond strength did not develop in the bonding of the metallic restorative materials, signs of bonding were found.

Analysis of Variance↗

PubMed1992

[A case of giant pigmented nevus with multiple meningiomas].

A 36-year-old female had a giant congenital pigmented nevus on her anterior trunk. She complained of muscle weakness of the right arm and leg in August 1988, and she was admitted to our hospital to take medical examinations in September 1988. Neurological examination revealed right hemiparesis and exaggerated deep tendon reflexes. Three small falx meningiomas were shown on CT scans and MR images, but they did not appear to be causes of her symptoms. CT-myelography and MR images revealed an intradural extramedullary tumor spreading from the foramen magnum to C2. Oncotomy and C1 laminectomy were performed. Histological finding was compatible with transitional meningioma. Neurological symptoms markedly improved after operation. This patient is considered as a case of neurocutaneous syndrome with central nervous system tumors. Considering that both giant pigmented nevus and meningioma originate from neural crest, they appear to be closely related each other. Such a combination of giant pigmented nevus and meningioma has not yet been reported.

Adult↗

PubMed1992

[Renal cell carcinoma with malignant peritoneal mesothelioma: report of a case].

We report a case of left renal cell carcinoma extending into vena cava with malignant peritoneal mesothelioma. A 41-year-old man presented to our outpatient clinic with macroscopic hematuria. Upon laparotomy, numerous white nodules were identified on diaphragm and serosa of liver, stomach, small intestine and mesentery. Biopsied specimen showed malignant mesothelioma of peritoneum and renal cell carcinoma of left kidney. He was treated with intraperitoneal cisplatinum and intravenous pirarubicin for mesothelioma, and chemoembolization for renal tumor. After two courses of therapy, he suffered from disseminated intravascular coagulation and died of subarachnoid hemorrhage. Autopsy revealed that intraperitoneal nodules were markedly decreased in number and renal tumor had changed into hemorrhagic necrosis, but tumor thrombus in vena cava had little necrotic change.

Adult↗

PubMed1992

[Two sibling patients with late-onset familial amyloidotic polyneuropathy and atypical clinical manifestations].

Brothers (case 1 and case 2) had familial amyloidotic polyneuropathy type 1 (FAP type 1) confirmed with sural nerve biopsy and DNA analysis. Both patients were unique in that their ages at onset were 56 and 52, and that their only manifestation was sensori-motor polyneuropathy, without clinically apparent autonomic involvements such as orthostatic hypotension, sweat dysfunction and sphincter dysfunction, or severe organ involvement such as gastrointestinal features and myocardial involvement after the onset. They are also unique in that their parents were healthy. The initial manifestation was sensori-motor polyneuropathy starting in the lower extremities. These atypical manifestations made the diagnosis of FAP type 1 difficult in the present cases. Based on reports in the literature and the present cases, there might be a tendency that in patients with late-onset FAP type 1 the clinical manifestations are generally mild and autonomic involvement and organ disturbance are absent or mild. In the etiological diagnosis of polyneuropathy, FAP type 1 should be considered especially in steadily progressive patients.

Age Factors↗

PubMed1992

[Countermeasures for urinary incontinence in patients with senile dementia: correlation between urinary incontinence severity, senile dementia severity, and activity of daily living].

The actual conditions of urinary incontinence in 101 patients with senile dementia (23 men and 78 women, average age 80 years) and their urinary control was studied. The three categories of 1) dementia severity, 2) activity of daily living and 3) degree of urinary incontinence, were each divided into five grades and the patients were evaluated accordingly. The correlation among the grades was studied. Of the 101 patients, 87 had urinary incontinence. These 87 were further subdivided into two groups: an ambulatory patient group (25) in which the patients could manage their own daily activity, and the bedridden group (62). The countermeasures for the first group of patients were, usage of a portable chamber pot for 6 patients and induced urination in 5. An anticholinergic agent was administered to 47 of the bedridden patients. The condition of urinary incontinence was reevaluated in both groups 4 weeks later. A high degree of correlation was observed among the grades of dementia severity, activity of daily living and urinary incontinence severity. After the countermeasures taken, improvement in urinary incontinence was observed in the 6 patients who used a portable chamber pot, and in the 5 patients who were subjected to induced urination. No improvement was seen in urinary incontinence in the bedridden patients who were treated with an anticholinergic agent. In conclusion, countermeasures for urinary incontinence in senile dementia should be indicated primarily for patients who can manage their own daily activity.

Activities of Daily Living↗

PubMed1992

Wettability of impression materials treated with disinfectants.

The purpose of this investigation was to comprehensively compare various combinations of impression materials, die stones and disinfectants so as to provide clinical guidelines for selection of materials. The effect of immersion disinfection on the wettability of five types of impression materials, polyether, light-cured polyether urethane dimethacrylate, polysulfide, hydrophilic and hydrophobic polyvinyl siloxanes, was evaluated. This evaluation was determined by contact angle measurement of two die stones on the impression materials and also by bubble formation in casts made from the same materials after disinfection. The disinfectants utilized were 0.5% sodium hypochlorite and 0.13% glutaraldehyde-phenate. There were significant interactive effects (P less than 0.02) on contact angle between stone and disinfectant, impression and disinfectant, and impression and stone. The effect of disinfection was found to vary among impression materials. Although there was a significant correlation found between contact angle and bubble formation, contact angle was not found to be a strong predictor of bubble formation in this study. For these findings, it is recommended to evaluate each disinfectant and impression material combination individually.

Analysis of Variance↗

PubMed1992

[Neoadjuvant chemotherapy (M-VAC) for locally invasive bladder cancer].

Eight patients with locally invasive bladder cancer (stages T2-T4, N0, M0; 7 men and 1 woman; mean age, 72.0 years; age range, 56 to 80 years) were treated with 2 cycles of neoadjuvant chemotherapy consisting of methotrexate, vinblastine, adriamycin and cisplatin (M-VAC). Seven of them underwent radical cystectomy after chemotherapy, while the bladder was preserved in one patient. Seven patients were free of disease during a mean follow-up period of 26.2 months (range 20-30 months). However, one patient whose pathological stage was pT2, N1 died with disease 27 months after radical cystectomy. The patient whose bladder had been preserved showed no recurrence after a follow-up period of 27 months. Pathological examination of the resected specimen after chemotherapy revealed no tumor tissue in three patients; one with negative cytology and two with positive cytology. Downstages were observed in two patients. Results showed that the toxicity of neoadjuvant M-VAC therapy is acceptable and that M-VAC therapy is effective against locally invasive transitional cell carcinoma of the bladder. The problem remains of how to assess the clinical stage more accurately before chemotherapy and radical cystectomy.

Aged↗

PubMed1992

[Hammock nonrefluxing ureteroileal anastomosis].

Hammock nonrefluxing ureteroileal anastomosis was performed on 14 patients who had urinary tract reconstruction using ileal conduit (4), Kock pouch (3), modified Kock pouch with plicated efferent limb (1) and ileal neobladder (6). Radiographic examinations showed ureteral reflux of contrast medium in one patient (7.1%), ureteral stenosis in one patient (7.1%) and no urine leakage. Three patients had pyelonephritis (21.4%) and no one had any upper tract urolithiasis. This technique provides a simple and reliable antireflux mechanism into ileal segments without nonabsorbable material.

Aged↗

PubMed1992

cdc2-like kinase is associated with the retinoblastoma protein.

The growth-suppressive activity of the retinoblastoma (RB) protein is suggested to be regulated by phosphorylation. In studies on the kinase that phosphorylates the RB proteins, we have previously found that RB proteins can be phosphorylated by purified cdc2 kinase. In this study, we noted that RB proteins immunoprecipitated from human cell lysates are weakly phosphorylated in the absence of purified cdc2 kinase. Immunoblot analysis showed the presence of p34cdc2 in the immunoprecipitates with anti-RB monoclonal antibody. In addition, the coprecipitated kinase was found to have the same substrate specificity as cdc2 kinase. The associated kinase activity was particularly high in cells arrested in G1/S and S phase by aphidicolin. Furthermore, RB proteins were shown to be phosphorylated in nuclear extracts by some endogenous cdc2-like kinase(s). These results suggest that cdc2-like kinase is the main kinase for phosphorylation of RB proteins in vivo.

Amino Acid Sequence↗

PubMed1992

[Clinical study of systemic juvenile rheumatoid arthritis (Still)].

Thirty-seven patients with systemic JRA were analyzed. Fifty four per cent of patients had mono-cyclic systemic type. Age at onset ranged from 6.0-6.8 years (median 6.4). Boys were more affected than girls (24/11). Cardiac involvement occurred in 10 patients (27%). Patients with cardiac troubles showed significantly much number of the white blood cell counts at admission and the max white blood cell count than those without cardiac troubles. Duration of positive CRP was shorter in patients with cardiac involvement who were all given cortico-steroid hormone those without cardiac involvement. This means that it is better to use steroid hormone early for patients with cardiac involvement. Patients with chronic arthritis type had higher elevated erythrocyte sedimentation rate and serum C3 level at admission and longer duration of positive CRP. We speculated that these date showed inflammation of joints. The onset subtype, which was determined by manifestations during the first 6 months of disease, was important for predicting clinical course and outcome.

Arthritis, Juvenile↗