Search PubMed⌕ Search

Biomedical subjects

S Shimizu

Publications and source records attributed to S Shimizu.

At least 739 records · Page 41Linked to original sources
PubMed1990

[Anti-HCV and long-term prognosis in patients with non-A, non-B post-transfusion hepatitis].

Anti-HCV was tested in serial serum samples of 20 patients with non-A, non-B post-transfusion hepatitis (NANB-PTH) who had been followed for more than 3 years after the onset. The rate of chronicity of disease was significantly higher in anti-HCV positive patients (12 out of 14, 85.7%) than in anti-HCV negative patients (group 1) (1 out of 6 patients, 14.3%). Among 14 anti-HCV positive patients, 7 lost anti-HCV during the follow-up period (group 2) and 6 of these 7 patients revealed normalization of liver dysfunction before or after the disappearance of anti-HCV. To the contrary, remaining 7 patients whose anti-HCV sustained positive (group 3) did show persistent abnormal liver function tests. Anti-HCV titer was significantly higher in group 3 than in group 2 at the point of 1 year after PTH. The titration of anti-HCV at 1 year after the onset of PTH was thought to be useful for estimating the prognosis of patients with post-transfusion hepatitis type C.

Adult↗
PubMed1990

[A well-differentiated hepatocellular carcinoma within adenomatous hyperplasia].

A 37-year-old male was admitted to hospital for jaundice and ascites. An ultrasonogram revealed a hypoechoic mass located in the right anterior inferior segment. A needle specimen of the liver was taken, and its biopsy led to a histological diagnosis of a hepatocellular carcinoma. The patient subsequently underwent an operation wherein it was found that the resected tumor that was taken was not clearly demarcated from the cirrhotic parenchyma. The histological diagnosis was an adenomatous hyperplasia. In a portion of this adenomatous hyperplasia, highly consistent hepatic cells and pseudogland formations were seen, confirming the diagnosis of a well-differentiated hepatocellular carcinoma within an adenomatous hyperplasia.

Adult↗
PubMed1990

[A case of transsphenoidal meningoencephalocele].

A 6-year-old boy was sent to us due to basal meningoencephalocele detected by MRI. He had had a past history of strabismus and morning glory syndrome since 6 months of age, as well as hypopituitary dwarfism since he was 3 years old. On admission, physical examination revealed hypertelorism and left coloboma. Laryngoscopic examination revealed a round mass covered by normal nasal mucose in the midline of the tegmen of the choana. X-ray tomogram and CT scan demonstrated an isodense mass protruding into the nasopharyngeal cavity through a bony defect of the sella turcica. Right carotid angiogram showed stenosis of the right internal carotid artery and abnormal fine vessels in the basal ganglia similar to basal Moyamoya network. There was an irregular filling of the right anterior cerebral artery. Left carotid angiogram showed an irregular filling of the left middle cerebral artery. MRI showed an anterior part of the third ventricle descending into, and the meningocele protruding into the nasopharyngeal cavity. It also showed a stalk extending from the hypothalamus into the meningocele, but the pituitary gland was not recognized. The meningocele was of the same signal intensity as CSF in both T1 and T2 weighted images. Growth hormone deficiency was confirmed by radioimmunoassay of the peripheral blood. An operation was scheduled transcranial to prevent snoring during sleep at age 9. The stalk was observed behind the chiasm during the operation, but a radical operation was not performed because of a possibility of postoperative hypothalamic-pituitary dysfunction. Transsphenoidal encephalocele is rare. So far as we could see, only 30 cases have been reported.(ABSTRACT TRUNCATED AT 250 WORDS)

Child↗
PubMed1990

[Absorption of tetrahydropyranyl adriamycin administered intravesically immediately after transurethral resection of bladder carcinoma].

Absorption of tetrahydropyranyl adriamycin (THP) administered immediately after transurethral resection of bladder carcinoma (TUR-Bt) has not been reported. In this study, we have examined the absorption of THP and the systemic toxicity in the early post-TUR period. Of 21 patients with bladder carcinoma, 10 had a solitary tumor and 11 multiple tumors. Twenty mg THP in 40 ml of sterile water was intravesically administered on days 1, 3, 5, 7, 14 and 28, and then every 4th week. The THP solution was retained for 2 hours. The blood THP concentration was measured 30 minutes and 2 hours after the intravesical administration on days 1, 7 and 28. No systemic side effects were observed. Thirteen of the 38 (34%) samples contained a detectable level (more than 1 ng/ml) of THP on the post-TUR-Bt on day 1, 8, of 42 (19%) on day 7, and 3 of 18 (17%) on day 28. Altogether, 24 of the 98 (24%) samples contained more than 1 ng/ml THP. The highest blood THP level was 23 ng/ml on day 1. The differences between frequency of detection of blood THP in the samples at 30 minutes and 2 hours were not statistically significant. The difference between average concentration of blood THP of patients with solitary and multiple tumors also was not significant. These results indicate that intravesical THP administration starting within 24 hours after TUR-Bt can not result in significant systemic absorption of THP, and the systemic toxicity can be avoided.

Absorption↗
PubMed1990

[Characteristic CT findings in Krabbe's disease].

In 12-month-old girl with Krabbe's disease, serial CT and MRI examinations showed characteristic findings, which were symmetric high densities in globus pallidus and thalami before and during the course of brain atrophy and decreased attenuation in white matter. The low densities in white matter were not so remarkable as other degenerative diseases affecting primarily white matter. The high densities in the globus pallidus changed into low densities with progression of the white matter hypodensities and brain atrophy. These findings on CT in Krabbe's disease may assist neurologists in narrowing the differential diagnosis and requesting appropriate laboratory tests.

Atrophy↗
PubMed1990

[Tumor imaging using 99mTc-hexamethylpropyleneamine oxime].

Tumor imagings have been performed in 32 tumor sites in 28 patients with a variety of malignancies by using 99mTc-HM-PAO. They have been compared with radionuclide angiography and conventional tumor imagings such as 67Ga citrate or 201TlCl scanning, and then their possible values have been evaluated for the investigation of tumor blood flow. Tumors were clearly visualized in 19 out of 32 sites, with 59% of positive rate. Good correlation was observed between the radioactivity in the tumor site on static image of 99mTc-HM-PAO and the radioactivity at arterial phase on radionuclide angiography, which represents tumor blood flow. The radioactivities in the marginal regions tended to be stronger than those in the center of large tumors. These results indicated that tumor imaging by 99mTc-HM-PAO mainly reflected tumor blood flow. On the other hand, 99MTc-HM-PAO imagings were not well correlated with 67Ga-studies, while they were coincided with all 201Tl scannings performed. It suggested that the affinity of 99mTc-HM-PAO to capillary wall also involved in its accumulation in the tumor. In conclusion, tumor imaging by 99MTc-HM-PAO was able to estimate tumor blood flow, and this examination would be helpful for the management of malignancies.

Adult↗
PubMed1990

[A case of primary anterior mediastinal choriocarcinoma].

A 25-year-old man was admitted to our hospital because of hemosputum and abnormal shadows on chest X-ray film. The chest film showed a mass shadow located in the right hilum and multiple coin lesions in bilateral lung fields. The chest CT scan showed a bulky mass sized 7 cm X 6 cm at the anterior mediastinum. This case was suspected to be choriocarcinoma because he was young, it was rapidly progressive and also because serum LDH and beta-HCG values were raised. The specimens obtained by surgical biopsy showed HCG-stain positive syncytiotrophoblasts. Cancer chemotherapy was started with CDDP and other anti-cancer drugs, but he succumbed about 3 months after admission. Autopsy findings showed no scar formation of his testes, and the primary lesion was finally diagnosed to be in the anterior mediastinum. Extra-gonadal choriocarcinoma is rare, and beta-HCG is very useful for its diagnosis and the follow-up of the clinical course.

Adult↗
PubMed1989

Microbial enzymes for creatinine assay: a review.

A novel metabolic pathway for the degradation of creatinine with N-methylhydantoin, N-carbamoylsarcosine and sarcosine as successive intermediates was found to operate in Pseudomonas putida 77 and many other microorganisms. Enzymes involved in this pathway were purified from cells of P. putida 77 and characterized. The first step, deimination of creatinine, is catalyzed by cytosine deaminase/creatinine deiminase. The following two steps, ring-opening of N-methylhydantoin and decarbamoylation of N-carbamoylsarcosine, are catalyzed by new enzymes, N-methylhydantoin amidohydrolase and N-carbamoylsarcosine amidohydrolase, respectively. The former requires ATP, Mg2+, and K+ for the hydrolysis and the reaction proceeds as follows: N-methylhydantoin + ATP + 2 H2O----N-carbamoylsarcosine + ADP + Pi. The latter catalyzes the following reaction; N-carbamoylsarcosine + H2O----sarcosine + NH3 + CO2. Sarcosine dehydrogenase was found to be the responsible enzyme for the oxidation of sarcosine to glycine in P. putida 77, but sarcosine oxidase was also found to be involved in this oxidation in several microorganisms. These enzymes were found to be useful tools for determination of creatinine.

Amidohydrolases↗
PubMed1989

Molecular cloning and expression of human hepatocyte growth factor.

Hepatocyte growth factor (HGF) is the most potent mitogen for mature parenchymal hepatocytes in primary culture, and seems to be a hepatotrophic factor that acts as a trigger for liver regeneration after partial hepatectomy and liver injury. The partial purification and characterization of HGF have been reported. We have demonstrated that pure HGF from rat platelets is a new growth factor effective at concentrations as low as 1 ng ml-1. The effects of HGF and epidermal growth factor (EGF) are additive. The activity of HGF is not species-specific, although it does not stimulate growth in Swiss 3T3 fibroblasts. HGF has a relative molecular mass (Mr) of 82,000 and is a heterodimer composed of a large alpha-subunit of Mr 69,000 and a small beta-subunit of Mr 34,000. Here we report the amino-acid sequence of human HGF determined by complementary DNA cloning and the expression of biologically active human HGF from COS-1 cells transfected with cloned cDNA. The nucleotide sequence of the human HGF cDNA reveals that both alpha- and beta-chains are contained in a single open reading frame coding for a pre-pro precursor protein of 728 amino acids.

Amino Acid Sequence↗
PubMed1989

Age distribution of circulating alpha-interferon.

A sensitive radioimmunoassay showed that circulating alpha-interferon in the plasma of healthy individuals was low in children and reached the highest level in the young adult, then declined gradually with age. Circulating alpha-interferon was 0.201 +/- 0.059 ng/ml in males (n = 19) and 0.184 +/- 0.076 ng/ml in females (n = 14) at ages 30-39 years old. It was noted that circulating alpha-interferon was maintained up to a certain level even in elderly individuals.

Adult↗
PubMed1989

Ketopantoyl-lactone reductase from Candida parapsilosis: purification and characterization as a conjugated polyketone reductase.

Ketopantoyl-lactone reductase (2-dehydropantoyl-lactone reductase, EC 1.1.1.168) was purified and crystallized from cells of Candida parapsilosis IFO 0708. The enzyme was found to be homogeneous on ultracentrifugation, high-performance gel-permeation liquid chromatography and SDS-polyacrylamide gel electrophoresis. The relative molecular mass of the native and SDS-treated enzyme is approximately 40,000. The isoelectric point of the enzyme is 6.3. The enzyme was found to catalyze specifically the reduction of a variety of natural and unnatural polyketones and quinones other than ketopantoyl lactone in the presence of NADPH. Isatin and 5-methylisatin are rapidly reduced by the enzyme, the Km and Vmax values for isatin being 14 microM and 306 mumol/min per mg protein, respectively. Ketopantoyl lactone is also a good substrate (Km = 333 microM and Vmax = 481 mumol/min per mg protein). Reverse reaction was not detected with pantoyl lactone and NADP+. The enzyme is inhibited by quercetin, several polyketones and SH-reagents. 3,4-Dihydroxy-3-cyclobutene-1,2-dione, cyclohexenediol-1,2,3,4-tetraone and parabanic acid are uncompetitive inhibitors for the enzyme, the Ki values being 1.4, 0.2 and 3140 microM, respectively, with isatin as substrate. Comparison of the enzyme with the conjugated polyketone reductase of Mucor ambiguus (S. Shimizu, H. Hattori, H. Hata and H. Yamada (1988) Eur. J. Biochem. 174, 37-44) and ketopantoyl-lactone reductase of Saccharomyces cerevisiae suggested that ketopantoyl-lactone reductase is a kind of conjugated polyketone reductase.

Alcohol Oxidoreductases↗
PubMed1989

Identification of regulatory sites in the biosynthesis of ubiquinone in the perfused rat heart.

The biosynthesis of ubiquinone was studied in an isolated perfused beating heart preparation from adult male rats to determine rate-limiting steps in the biosynthetic pathway. The isolated heart could incorporate p-hydroxy[U-14C]benzoate into ubiquinones (ubiquinone-9 and -10) and two other lipids which were identified as 3-nonaprenyl 4-hydroxybenzoate and 3-decaprenyl 4-hydroxybenzoate. No other lipids could be detected. Addition of unlabeled mevalonolactone to the perfusate stimulated the rate of incorporation of p-hydroxy[U-14C]benzoate into 3-nonaprenyl 4-hydroxybenzoate and 3-decaprenyl 4-hydroxybenzoate. The level of radioactivity in these intermediates was much greater than that in ubiquinone-9 and -10. These results show that in the intact heart there is a large excess capacity to form postmevalonate isoprenoid precursors of ubiquinone and suggest a possible regulatory step at the premevalonate level. Moreover, the accumulation of prenylated derivatives of 4-hydroxybenzoic acid indicates further rate limitation at one or more of the subsequent steps in conversion of these intermediates to ubiquinone.

Animals↗
PubMed1989

Gelatinases of murine metastatic tumor cells.

The properties of gelatinases secreted in culture medium of murine fibroblasts, macrophages, colonic carcinoma, FBJ virus-induced osteosarcoma, Lewis lung carcinoma and mammary tumor cells were compared. Normal fibroblasts and macrophages secreted gelatinases of 60,000 and 95,000 molecular weights, respectively. Tumor cells secreted both of these gelatinases, although the relative amounts of the 60 kDa and 95 kDa gelatinases differed among the cell lines. The cell lines that had the greatest metastatic potential to the lung secreted the highest amount of 95 kDa gelatinase. The 95 kDa gelatinase produced by tumor cells had properties similar to that of macrophages.

Animals↗