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Biomedical subjects

S Okada

Publications and source records attributed to S Okada.

At least 1,135 records · Page 63Linked to original sources
PubMed1987

Serum C3 and C4 levels and complement-dependent antibody-mediated cytotoxic activity of islet cell surface antibody in type 1 (insulin-dependent) diabetic children.

The role of complement in the pathogenesis of diabetes was studied in 31 Type 1 (insulin-dependent) diabetic children by assaying serum islet cell surface antibody, C3, C4 and serum complement-dependent antibody-mediated cytotoxicity. Nine of 21 islet cell surface antibody-positive children were within 5 months of disease onset and showed significantly lower serum C3 and C4 levels than either 1 year later or the remainder of the islet cell surface antibody-positive children at 6-12 months after disease onset. The overall trend of all islet cell surface antibody-positive diabetic children within 1 year of disease onset was toward increased serum C3 and C4 levels as the disease progressed. Serum C4 concentration and complement-dependent antibody-mediated cytotoxicity which showed an initial negative correlation were uncorrelated 1 year later. Four children who were initially strongly islet cell surface antibody-positive but negative 1 year later also exhibited significantly higher (p less than 0.05) mean serum C4 levels after 1 year. There was a significant decrease in complement-dependent antibody-mediated cytotoxicity when sera from the diabetic children were treated with either ethylene glycol tetra-acetic acid or ethylene diamine tetra-acetic acid. These data strongly suggest that complement-dependent antibody-mediated cytotoxicity induced by the classical complement pathway involving an islet cell surface antibody may play an important role in the pathogenesis of Type 1 diabetes.

Adolescent↗
PubMed1987

Mesangial changes in IgA nephropathy in children.

The mesangial changes in 92 renal biopsy specimens from 81 children with IgA nephropathy were correlated with the clinical and the other renal biopsy findings. Three types of mesangial changes were identified: mesangial hypercellularity was predominant compared with the increase in matrix in 34 biopsy specimens (type A), the degrees of mesangial hypercellularity and matrix increase were similar in 36 (type B) and matrix increase was predominant in 22 (type C). The interval between the onset of disease and biopsy was significantly shorter in biopsies with type A mesangial changes (P less than 0.01) and significantly longer in those with type C (P less than 0.01). Serial pathologic observations revealed that predominant mesangial hypercellularity was almost exclusively seen in the initial biopsy but predominant matrix increase was usually seen in the follow-up biopsy. The percentage of glomeruli showing sclerosis was significantly higher in biopsies with type C mesangial changes (P less than 0.05). At the latest follow-up, 58% of the patients showing type A and 57% showing type B lost their proteinuria, whereas only 9% showing type C lost their proteinuria (P less than 0.01). These findings suggest that predominant mesangial hypercellularity is characteristic of the early lesion of childhood IgA nephropathy, and progression of disease leads to gradual decrease of mesangial cellularity and increase of matrix with sclerosis.

Biopsy↗
PubMed1987

A case of amputation neuroma presenting proptosis.

A case of amputation neuroma, presenting incidious proptosis, was reported in a 44-year-old man. To the best of our knowledge the case seems to be the first report of amputation neuroma caused by trauma in the orbita.

Adult↗
PubMed1987

Biochemical heterogeneity in I-cell disease. Sucrose-loading test classifies two distinct subtypes.

Since we observed the normalization of intracellular hydrolases in some cell lines of I-cell disease (ICD) by 88 mmol/l sucrose, we have hypothesized that the degree of responses of the hydrolases might be due to biochemical heterogeneity among ICD. In this study the changes of intracellular lysosomal enzymes as well as Golgi enzymes including N-acetylglucosaminyl phosphotransferase (GlcNAcPTase) and extracellular hexosaminidase (HEX) were investigated using normal and ICD fibroblasts. Sucrose loading induced the activities of intracellular HEX and GlcNAcPTase simultaneously only in responding-type ICD cells, and not in nonresponding-type ICD cells, indicating that two biochemical heterogeneous groups exist in ICD.

Cells, Cultured↗
PubMed1987

X-ray photoelectron spectroscopic studies of the adsorption of salivary constituents on enamel.

Time-dependent change of adsorption of salivary components on the outermost surface layer of enamel was studied by x-ray photoelectron spectroscopy. Adsorption of proteinaceous components, as monitored in terms of the relative mass of nitrogen, was detected within 30 min, increased with time, and reached a plateau at 90 min. Thus, the ratio of nitrogen to calcium in the two-hour sample increased to about 240 times that in the control sample. The ratio of carbon to nitrogen on the surface decreased to about one-half of that in the control sample. The data established the time required for equilibrium between the proteinaceous component in saliva and the amount of material adsorbed onto the tooth surface.

Adsorption↗
PubMed1987

Tumor accumulation of D-selenomethionine-75Se in tumor-bearing mice.

The radioactivity distribution of 75Se-labeled D-selenomethionine (D-SeMet-75Se) was investigated in tumor-bearing mice in order to develop a new radioactive diagnostic agent. D-SeMet-75Se was enzymatically prepared from commercially available L-selenomethionine-75Se (L-SeMet-75Se) by using amino acid racemase and immobilized L-amino acid oxidase. No difference between D- and L-SeMet-75Se was found in the excretion rate into urine and feces in normal mice within 48 h after administration. The in vivo uptake of D-SeMet-75Se in both Ehrlich solid tumor and sarcoma-180 solid tumor was several times higher than that of L-SeMet-75Se but the uptake of D- and L-SeMet-75Se were similar in the pancreas. These results indicated that D-SeMet-75Se might be useful as a tumor-imaging agent. In vitro experiments on Ehrlich ascites tumor cells showed that D-SeMet-75Se was incorporated into the tumor cells by a Na+-dependent active transport system similar to L-SeMet-75Se and that a transport mechanism specific for D-SeMet-75Se might be present in tumor cells in addition to a transport system common to both D- and L-forms.

2,4-Dinitrophenol↗
PubMed1987

Bilateral sensorineural hearing loss associated with Mycoplasma pneumoniae infection.

Three cases of persistent bilateral sensorineural hearing loss following Mycoplasma pneumoniae (MP) infection are reported. These cases were characterized by highly elevated MP complement fixation titer and cold hemagglutinin titer. All the patients had bilateral acute otitis media with a moderate to high degree of mixed hearing loss in the early stage following primary atypical pneumonia (PAP).

Adult↗
PubMed1987

WF-10129, a novel angiotensin converting enzyme inhibitor produced by a fungus, Doratomyces putredinis.

WF-10129 is an angiotensin converting enzyme (ACE) inhibitor produced by Doratomyces putredinis. IC50 of the compound is 1.4 X 10(-8) M for the ACE activity. WF-10129 was purified from cultured filtrate by successive ion exchange chromatography and HPLC. The chemical structure 1 was elucidated on the basis of spectroscopic and chemical evidence. The compound is a dipeptide composed of L-tyrosine and a novel amino acid. WF-10129 inhibits the pressor response of angiotensin I when administered intravenously at 0.3 mg/kg in rats.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1987

Effects of prolonged oral cimetidine, ranitidine, and famotidine therapy on antipyrine elimination.

The effects of three histamine H2-receptor antagonists on the antipyrine metabolizing capacity of the liver were studied in 32 patients with gastrointestinal disorders and in three healthy volunteers. The drugs studied were 800 mg and 400 mg of cimetidine, 300 mg of ranitidine, and 40 mg of famotidine daily. Only cimetidine at 800 mg/day inhibited hepatic antipyrine metabolism, and the inhibitory effects disappeared rapidly with no accumulation.

Administration, Oral↗
PubMed1987

[Cholesteatoma of the ureter: a case report].

A 68-year-old woman was hospitalized complaining of right flank pain. The excretory pyelogram revealed that the right kidney was hydronephrosis, and a retrograde pyelogram showed stringy filling defects in the middle portion of the right ureter. Suspecting a right ureter tumor, a right ureteronephrectomy was performed. The pathological diagnosis was ureteral cholesteatoma which is a rare condition with reports of only 9 cases in the Japanese literature. Although the possibilities of malignant change has been debatable, long term follow up would be mandatory.

Aged↗
PubMed1987

Macroscopic hematuria in childhood IgA nephropathy.

The clinical presentation, initial laboratory and renal biopsy findings, and subsequent clinical course in 205 children with IgA nephropathy were studied retrospectively. The findings in the 119 patients with macroscopic hematuria and those in the 86 without macroscopic hematuria were compared. There were no differences with regard to sex distribution, age at onset, initial renal function, incidence of hypertension, degree of proteinuria and degree of mesangial proliferation. At the latest follow-up, 3% of the patients with macroscopic hematuria and 8% without macroscopic hematuria had developed chronic renal failure; 8% of the patients with macroscopic hematuria and 20% without had heavy proteinuria with or without hypertension (p less than 0.01); 41% of the patients with macroscopic hematuria and 24% without macroscopic hematuria had normal urine, blood pressure and GFR (p less than 0.05). The disease appears to follow a significantly more benign course in children with macroscopic hematuria than in those without macroscopic hematuria. These observations suggest some macroscopic hematuria-related differences in the natural history of childhood IgA nephropathy.

Child↗
PubMed1987

[One stage reconstruction of penis with free forearm flap].

One stage reconstruction of the penis using free tissue transfer was performed on a 43-year-old man who had total penectomy for carcinoma of the penis. A free forearm tissue flap was used to reconstruct urethra and for external skin coverage and Jonas silver penile prosthesis was used as a stent. Nutrient vessels (one artery and two veins) were anastomosed with a lateral circumflex femoral artery and two branches of the saphenous veins respectively and the nerve of flap was anastomosed with the pudendal nerve. We believe that this method is functionally and cosmetrically acceptable for reconstructing the penis, although unfortunately extrusion of the prosthesis ensued 63 days after the operation in our case.

Adult↗
PubMed1987

Induction and subsequent repair of DNA damage by fast neutrons in cultured mammalian cells.

The induction and repair of DNA damage were studied by a DNA unwinding method in mouse L5178Y cells exposed to fast neutrons. DNA lesions induced by fast neutrons were classified into three types from their repair profiles: fast-reparable breaks (T1/2 = 3-5 min), slow-reparable breaks (T1/2 = 70 min), and nonreparable breaks. The repair rates of both fast-reparable and slow-reparable breaks were almost the same as those of corresponding damage induced by low-LET radiation. Neutrons induced a smaller amount of fast-reparable damage, an almost equal amount of slow-reparable damage, and a larger amount of nonreparable damage than those induced by equal doses of gamma rays or X rays. RBEs for fast- and slow-reparable damage were 0.3 and 0.9, respectively. The RBE for nonreparable damage was dose dependent and was 1.4 at the level of 100 breaks/10(12) Da DNA. Among the three types of lesions, only the nonreparable damage levels correlated with the linear-quadratic shape of the survival curves and with the enhanced killing effectiveness of neutrons (RBE = 1.7 at D0).

Animals↗