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Y Nonaka

Publications and source records attributed to Y Nonaka.

At least 55 records · Page 3Linked to original sources
PubMed1996

[Assay of specific anti-Chlamydia pneumoniae antibodies by ELISA method. 2. studies on clinical usefulness and serological diagnostic standards].

We measured anti-Chlamydia pneumoniae (C. pneumoniae) specific antibody titers by means of a newly-developed enzyme-linked immunosorbent assay (ELISA) method using an anti-C. pneumoniae specific antibody detection reagent. The clinical usefulness of this method was hereby evaluated. The IgG, IgA and IgM titers in 418 serum specimens obtained from patients with respiratory tract infections were measured by this new ELISA method, and the results were compared with the titers determined for the same specimens with the micro immunofluorescence (Micro-IF) method. The results showed good correlation coefficients for IgG, IgA and IgM. The two assay methods showed high agreement rates for positivity and for negativity. Specimens which did not yield the same results with the ELISA method and the Micro-IF method were subjected to analysis by the Western blot method, and the rates of agreement with the ELISA results were high. In addition, the child (0 approximately 15 yrs old; n = 122) and adult (16 approximately 90 yrs old; n = 133) cases were classified on the basis of being antigen-positive or antigen-negative at the initial examination, and their antibody-positive rates were determined. The adults showed no statistically significant differences in the antibody-positive rates for either IgG or IgA antibodies as a function of the pretreatment antigen status. However, the children showed statistically significant (p < 0.001) differences in the antibody-positive rates for both IgG and IgA antibodies as a function of the antigen status in the antigen-positive group compared with the rates in the antigen-negative group. Furthermore, the IgM-positive rates for the children were high in the antigen-positive group compared with the rates in the antigen-negative group, and the difference was statistically significant (p < 0.001). The IgM-positive rates in the adults were also significantly (p < 0.05) different between the antigen-positive group and the antigen-negative group. The Micro-IF method was applied to 34 specimens from antigen-positive patients, and 22 specimens were found to show an IgG titer of > or = 512 or an IgM titer of > or = 16. The diagnoses of these patients were acute respiratory disease in sixteen, pneumonia in four. Application of the ELISA-method to those 22 specimens showed all of them to exhibit IgG absorbance of > or = 0.6 and IgA absorbance of 0.2. The results described above indicate the clinical usefulness of our new ELISA method for the detection of antibodies specific for C. pneumoniae. The significance of this ELISA method for serological diagnosis of C. pneumoniae infections and the criteria for diagnosis of acute infections were also discussed.

Adolescent↗
PubMed1996

Effects of ebelactone B, a lipase inhibitor, on intestinal fat absorption in the rat.

Ebelactones A and B, natural products from Streptomyces aburaviensis are potent inhibitors of pancreatic lipase. Lipase is the key enzyme required for the absorption of dietary triglycerides (TG). Ebelactone B inhibited, in a dose-dependent manner, the intestinal absorption of fat after fat-feeding in the rat. The most effective inhibition was observed when the inhibitor was administered at 60 min prior to fat-feeding. When ebelactone B (10 mg/kg) was administered, the serum levels of TG (58%) and cholesterol (36%) were decreased. Since ebelactone B effectively inhibitors absorption of dietary fat, if may provide a promising means for prophylaxis or therapeutics of hyperlipidemia and obesity.

Animals↗
PubMed1996

[A case of hemolysis induced by lansoprazole].

Hemolytic anemia and possible aplastic crisis with symptoms including jaundice, general fatigue and dark urine developed in a man being treated only by lansoprazole. Five days later, he was treated with antibiotics. The next day, he was admitted to our hospital because of jaundice. On admission, the hemoglobin was 14.0 g/dl, reticulocyte count 8/1000, platelets 79 x 10(9)/l and total bilirubin 12.4 mg/dl (indirect bilirubin 9.5 mg/dl). The above medications were discontinued. The direct Coombs antiglobulin test was positive. Examination of the complement revealed a C3 fiter at the upper limit of normal and an increased C4 and CH50. Three days after admission, he had a severe anemia. The hemoglobin was 3.3 g/DL. We thought it possible that aplastic crisis had followed the hemolytic anemia induced by lansoprazole. He was treated with blood transfusions and corticosteroids. He recovered from anemia within three weeks. Exhaustive studies to identify the cause of the hemolytic anemia were undertaken with negative results. We detected IgG antibody to lansoprazole. We believe that the hemolytic anemia was induced by lansoprazole.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed1995

Frog cytochrome P-450 (11 beta,aldo), a single enzyme involved in the final steps of glucocorticoid and mineralocorticoid biosynthesis.

A cDNA for cytochrome P-450(11 beta,aldo) was cloned from a library of bullfrog interrenal tissue (tissue corresponding to the mammalian adrenal gland). The 1919-bp cDNA encoded a protein of 517 amino acids. Its amino acid sequence was highly similar to the sequences of bovine P-450(11 beta) and rat P-450(11 beta,aldo) when P-450(11 beta) family enzymes reported to date were examined. The enzyme expressed in COS7 cells had the 11 beta-hydroxylation, 18-hydroxylation activities and aldosterone synthetic activity. Northern-blot and immunoblot analyses suggested that a single P-450(11 beta) enzyme was expressed in bullfrog interrenal tissue. These results suggest that a single enzyme catalyzes the final steps of glucocorticoid and mineralocorticoid biosynthesis in bullfrog interrenal tissue as in bovine adrenal gland. A phylogenetic tree of CYP11B genes suggests that the frog enzyme diverged at an earlier evolutionary time from other vertebrate enzymes. Immunohistochemical and in situ hybridization studies indicated that steroidogenic cells existed in the outer region of interrenal tissue more densely than in the inner region, whereas some medullary cells made clusters like islets. Most of the cells were diffusely distributed in the tissue.

Amino Acid Sequence↗
PubMed1995

Cloning and expression of cytochrome P450(11 beta) of porcine adrenal cortex.

Four cDNA clones were isolated from a porcine adrenal gland library by using a bovine cytochrome P450(11 beta) cDNA fragment as a probe. Nucleotide sequences of the four clones overlapped with each other. The deduced amino acid sequences indicated that these clones were derived from a porcine P450(11 beta) cDNA. Consecutive alignment of these clones covered almost 70% of a coding region of the cDNA, but its 5'-terminus was missing. The adrenal mRNA was reverse-transcribed, and polymerase chain reaction was used to obtain a cDNA fragment including the 5'-terminus. A cDNA constructed from this fragment and the isolated four fragments covered the entire apparent open reading frame of the enzyme, which was thus concluded to comprise 503 amino acids including a putative extension peptide of 24 amino acids at the NH2-terminus. The amino acid sequence was 82% identical to that of bovine P450(11 beta)-3. The cDNA was transfected into COS-7 cells, and steroidogenic activity of the cells was measured. The cells not only converted 11-deoxycorticosterone to corticosterone and 18-hydroxycorticosterone, but also produced aldosterone. Thus we conclude that the primary sequence of porcine P450(11 beta) which plays a role in the biosynthesis of glucocorticoids as well as mineralocorticoids was determined.

18-Hydroxycorticosterone↗
PubMed1995

Cytochrome P450(11 beta): structure-function relationship of the enzyme and its involvement in blood pressure regulation.

Cytochrome P450(11 beta) is deeply involved in the final steps of biosynthesis of mineralocorticoids. This paper deals with following issues about this enzyme. (1) The structure and function of the enzymes of various animal species are discussed. By making alignment of amino acid sequences of the enzymes, we identified peptide domains essential for the enzyme actions such as a putative steroid binding domain and a heme binding region. Estimates of molecular similarity among the P450(11 beta) family enzymes suggested that the enzymes having both 11 beta-hydroxylation activity and aldosterone (ALDO) synthetic activity of certain animals such as frog, cattle and pig are more similar to the ALDO synthases of the other animals, such as rat, mouse and human, than the 11 beta-hydroxylases of these animals. (2) The molecular nature of the P450(11 beta) family enzymes of genetically hypertensive rats as well as adrenal regeneration hypertension (ARH) rats is examined. (i) Mutation was found in the P450(11 beta) gene of Dahl's salt-resistant normotensive rat. Steroidogenic activity expressed by the mutated gene accounted well for abnormal plasma levels of steroid hormones in this rat. (ii) 11 beta-, 18- and 19-Hydroxylation activities of adrenal mitochondrial prepared from spontaneously hypertensive rat (SHR), Wistar-Kyoto rat (WKY), and stroke-prone (SP)-SHR were not significantly different from each other. Levels of mRNA of ALDO synthase in adrenal glands of 50-week-old SHR was significantly lower than those of 10-week-old SHR, WKY and SHR-SP. (iii) No significant difference in 19-hydroxylation activity was found between adrenal mitochondria prepared from ARH rat and those from control rat. The level of message of ALDO synthase was lower in adrenal glands of ARH rat.

Aldosterone↗
PubMed1995

Angiotropic B-cell lymphoma presenting with progressive dementia: an autopsy case and review of the literature in Japan.

We report an autopsy case of angiotropic lymphoma and review the literature in Japan. A 68-year-old female presented with transient right facial nerve palsy, right hemiplegia and progressive dementia. Laboratory studies showed raised erythrocyte sedimentation rate, C-reactive protein and serum lactate dehydrogenase. Computed tomography of the brain did not show any abnormal density areas but on T2-weighted magnetic resonance imaging high signal areas were recognized at the basal ganglia. She was diagnosed as having dementia caused by cerebrovascular insufficiency. She soon developed a febrile state and died of respiratory failure within three months of presentation. Postmortem examination showed widespread angiotropic B-cell lymphoma.

Aged↗
PubMed1994

KF17837 ((E)-8-(3,4-dimethoxystyryl)-1,3-dipropyl-7-methylxanthine), a potent and selective adenosine A2 receptor antagonist.

8-(3,4-Dimethoxystryryl)-1,3-dipropyl-7-methylxanthine exhibited high affinity and selectivity for adenosine A2A receptors in binding assay using rat striatal A2A receptors labeled with [3H]2-[p-(2-carboxyethyl)-phenethylamino]-5'-N-ethylcarboxamido adenosin e (CGS21680). The affinity was stereo selective: the E isomer, KF17837, showed a Ki value of 1.0 +/- 0.057 nM for the A2A receptors, whereas the Z isomer showed much lower affinity. KF17837 had 62-fold selectivity for the A2A receptors versus rat forebrain A1 receptors labeled with [3H]N6-cyclohexyladenosine (CHA). KF17837 was rapidly photoisomerized to form a stable equilibrium mixture (18% E - 82% Z), KF17837S, which showed Ki values of 7.9 +/- 0.055 nM and 390 +/- 68 nM for the A2A and A1 receptors, respectively. The inhibition type was competitive for [3H]CGS21680 binding. In rat pheochromocytoma PC12 cells KF17837S antagonized cAMP accumulation induced by 1 microM CGS21680 via the A2A receptors, with an IC50 value of 53 +/- 10 nM. cAMP accumulation induced by 10 microM 5'-N-ethylcarboxamidoadenosine via the A2B receptors in Jurkat cells (human T-cell line) was inhibited by KF17837S with an IC50 value of 1500 +/- 290 nM. These results indicate that KF17837S (and hence KF17837) is a highly potent and selective adenosine A2A receptor antagonist.

Adenosine↗
PubMed1994

Endoscopical segmental piecemeal tumorectomy for nodular elevation of colorectal tumor: applicability and patient's quality of life.

Endoscopical segmental piecemeal tumorectomy (ESPT) for nodular elevation of colorectal tumor is advantageous in terms of minimizing both surgical invasion and postoperative burden to the patients. Nodular elevation of colorectal tumors is said to occur when the body of the tumor is adenomatous and the surface of the focal cancer grows more horizontally into the lumen than vertically. We report here four cases of nodular elevation of colorectal tumors which were each treated by different surgical procedures.

Aged↗
PubMed1994

Ovarian metastasis in patients with colorectal carcinoma.

The records of 159 patients who underwent surgical resection of colorectal cancer were reviewed to assess the incidence of ovarian metastasis and to define the role of oophorectomy. Four of these patients presented with metachronous metastases, and one patient had synchronous ovarian involvement. The incidence of ovarian involvement was higher in younger patients. While most patients with ovarian involvement had the primary tumor located at the rectosigmoid region, a similar distribution of the primary tumor was observed in patients without ovarian metastasis. The histological type and degree of differentiation was similar regardless of whether or not ovarian metastasis was present. Of the patient without ovarian metastasis, 57% presented with nodal metastases and 3.2% with peritoneal dissemination, while all patients with ovarian metastasis had nodal and peritoneal involvement. Our results suggest that histological type and degree of differentiation of the primary tumor do not influence likelihood of ovarian metastasis. However, the exposure of the tumor to the serosal surface and the subsequent peritoneal dissemination may be an important route by which malignant tumor cells reach the ovaries. However, due to the wide lymphatic involvement in patients with ovarian metastasis, the lymphatic route may be important as well. Thus, we consider that oophorectomy should be performed in all postmenopausal women, when the ovaries are macroscopically affected, and in premenopausal patients with Astler-Coller B2 tumors or over.

Adult↗
PubMed1993

Effect of reactive oxygen intermediates on the in vitro invasive capacity of tumor cells and liver metastasis in mice.

We studied the role of reactive oxygen intermediates (ROIs) in experimental liver metastasis induced in mice by the inoculation of COLON 26-M5 murine colon cancer cells, a highly metastatic variant of COLON 26 cells, and the effect of ROIs on the invasive capacity of the cells in an in vitro chemo-invasion assay model using reconstituted basement membrane matrigel. We also measured the release of ROIs from cells using electron spin resonance (ESR) spectrometry. Hydroxyl radicals (.OH) were constitutively released from the cells. This release was augmented by pre-treatment with phorbol 12-myristate 13-acetate (PMA). In experimental liver metastasis in CDF1 mice, the administration of recombinant human superoxide dismutase (r-hSOD) significantly increased the number of metastatic nodules, while administration of catalase significantly inhibited metastasis formation. In vitro pre-treatment of cells with PMA significantly increased the number of metastatic nodules. Invasive capacity of the cells was markedly augmented by pre-treatment with PMA. PMA-induced augmentation was significantly inhibited by the simultaneous addition of r-hSOD to the assay. Catalase had no significant effect. Our findings suggest that ROIs play an important role in tumor invasion and metastasis, and that hydrogen peroxide (H2O2) may contribute to the retention or extravasation of circulating tumor cells. Furthermore, the superoxide anion (O2-) released by tumor cells may play an important role in basement membrane degradation.

Animals↗
PubMed1993

Cloning and expression of phospholipase A2 from guinea pig gastric mucosa, its induction by carbachol and secretion in vivo.

A cDNA encoding phospholipase A2 (PLA2) was cloned from guinea pig gastric mucosa using a rat pancreatic-PLA2-cDNA fragment as a probe. The cDNA contains an open reading frame sufficient to encode the entire amino-acid sequence of a PLA2-precursor protein consisting of 146 amino acids, including a putative 16-residue signal peptide and a 6-residue activation peptide at the NH2-terminus. Its nucleotide sequence exhibits 70% similarity to that of rat pancreatic PLA2 cDNA. The deduced amino-acid sequence has all the typical pancreatic PLA2 characteristics, with the exception of the substitution of Phe for Tyr at position 28 in the calcium-binding loop of the mature enzyme. When an expression vector containing the PLA2 cDNA was transfected into COS-7 cells, a major portion of the proenzyme was secreted into the culture medium. Northern-blot analysis showed the mRNA was present in guinea pig lung and pancreas at much lower levels than in the stomach. The effect of carbachol, a muscarinic acetylcholine agonist, on the secretion of gastric PLA2 and on its mRNA level in the gastric mucosa were examined. PLA2 secretion into the gastric juice was maximal 30 min after the subcutaneous administration of carbachol (0.4 mg/kg). It also increased the PLA2-mRNA level in the tissue, the maximal mRNA level being delayed about 15 min compared with that in PLA2 secretion. These results suggest that vagal stimuli may contribute to PLA2 secretion and its compensatory synthesis, and that the secreted PLA2 may participate in the digestion of dietary and biliary phospholipids in the small intestine of guinea pig.

Amino Acid Sequence↗
PubMed1993

Dahl's salt-resistant normotensive rat has mutations in cytochrome P450(11 beta), but the salt-sensitive hypertensive rat does not.

Molecular cloning of cytochrome P450(11 beta) cDNAs from the adrenal glands of Dahl's salt-sensitive hypertensive (DS) and salt-resistant normotensive (DR) rats was performed using a combined technique of the first strand cDNA synthesis by reverse transcriptase followed by polymerase chain reaction. The cDNA sequence of P450(11 beta)-DS was identical to that of wild type P450(11 beta). In contrast, the clone obtained from the DR rat contained six nucleotide substitutions causing five amino acid alterations (Arg-127-->Cys, Val-351-->Ala, Val-381-->Leu, Ile-384-->Leu, and Val-443-->Met). When the two cDNAs were expressed in COS-7 cells and steroid conversion rates of the transformed cells were determined, a ratio of 18-hydroxylation to 11 beta-hydroxylation of 11-deoxycorticosterone by P450(11 beta)-DS-expressed cells was 0.58, whereas that by P450(11 beta)-DR-expressed cells was 0.23. Plasma levels of 18-hydroxy-11-deoxycorticosterone and corticosterone (the 11 beta-hydroxylation product of 11-deoxycorticosterone) in DS and DR rats well reflected the steroidogenic activities of the two P450s. These results suggest that the characteristic plasma steroid level of the DR rat is caused by the mutations in P450(11 beta) gene and may act to maintain the normotensive blood pressure in this rat strain during sodium loading.

Amino Acid Sequence↗
PubMed1993

Three forms of rat CYP11B genes: 11 beta-hydroxylase gene, aldosterone synthase gene, and a novel gene.

We isolated three genomic clones of rat P-450(11 beta) genes (CYP11B). Two of them corresponded to 11 beta-hydroxylase gene (CYP11B1) and aldosterone synthase gene (CYP11B2), respectively. The third one was a novel gene resembling both CYP11B1 and CYP11B2, and was named CYP11B3 gene (CYP11B3). CYP11B2 and CYP11B3 are located tandemly in the genome in the same direction approximately 24 kb apart. These three genes were highly homologous in their amino acid coding regions, with 88% (CYP11B1 to CYP11B2), 89% (CYP11B2 to CYP11B3), 96% (CYP11B1 to CYP11B3) nucleotide identity. The numbers and the locations of the exons of these three genes also exactly corresponded to each other. However, the nucleotide sequences of the 5' upstream regions of CYP11B1 and CYP11B2 were significantly different, suggesting different transcriptional regulations. CYP11B3 had almost the same sequence as CYP11B1 gene in the 5' upstream region. A putative Ad4 site, a cis-acting element present in the promoter regions of all the steroidogenic P-450s so far reported [Morohashi, K., Honda, S., Inomata, Y., Handa, H., Omura, T. (1992) J. Biol. Chem. 267, 17913-17919], was found in the promoter regions of both CYP11B1 and CYP11B2. Gel retardation analysis showed the binding of Ad4BP purified from bovine adrenal cortex to these two Ad4 sites. We analyzed the relative abundance of the mRNAs corresponding to these three genes by the generation of RT-PCR libraries from rat adrenal total RNAs.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
PubMed1993

[Null-cell non-Hodgkin's lymphoma presenting with a mass in the chest wall after tuberculous pyothorax].

A 59-year-old male, who was treated with artificial pneumothorax for pulmonary tuberculosis 42 years previously, presented with a painful mass in the left lateral chest wall and lymph node swelling in the left neck. A chest CT-scan revealed a tumor shadow extending from the outer chest wall to the pleural cavity containing pus surrounded by calcified pleura. 67Ga scintigraphy showed accumulation of the radionuclide in the left lateral chest and left neck. Biopsy specimen obtained from both the chest tumor and cervical lymph node revealed diffuse large cell lymphoma. Immunostaining failed to demonstrate CD1, CD3, CD4, CD8, CD13, CD20, immunoglobulin, alpha, gamma, mu, delta, kappa and lambda chains, indicating null cell characteristics. Chemotherapy consisting of cyclophosphamide, doxorubicin, vincristine, prednisolone and bleomycin and irradiation resulted in a temporary decrease of the tumor and lymph nodes, but the patient died of pneumonia 14 months after the onset of disease. Since the levels of serum lactate dehydrogenase and immunosuppressive acidic protein varied in parallel to the disease activity, they appeared to be useful for the assessment of therapeutic effects during the clinical course. Approximately 100 cases of non-Hodgkin's lymphoma developing after tuberculous pyothorax have been reported in this country, among which the incidence of null cell type is exceedingly rare.

Empyema, Tuberculous↗
PubMed1992

Molecular biology of rat steroid 11 beta-hydroxylase [P450(11 beta)] and aldosterone synthase [P450(11 beta, aldo)].

The molecular features of rat steroid 11 beta-hydroxylase [P450(11 beta)] and aldosterone synthase [P450(11 beta, aldo)] are discussed. P450(11 beta) is biosynthesized as a precursor form composed of 499 amino acids, having a 24-amino acid extension peptide. Two species of P450(11 beta, aldo) were identified; a precursor form of P450(11 beta, aldo)-1 is 510 amino acids long and has a 34-amino acid extension peptide, while that of P450(11 beta, aldo)-2 is 500 amino acids long and has a 24-amino acid extension peptide. The 286th amino acid of P450(11 beta, aldo)-1 is Glu, while that of P450(11 beta, aldo)-2 is Lys. The cDNA-expression studies showed that P450(11 beta, aldo)-1 had the aldosterone producing activity whereas P450(11 beta, aldo)-2 had no activity, suggesting that Glu286 of P450(11 beta, aldo) plays an important role in the catalysis. The amino acid sequence of a region in P450(11 beta) from Leu337 through Pro352 is highly conserved among the steroidogenic P450s. Functional expression studies on the cDNAs for two P450(11 beta)s showed that P450(11 beta) catalyzes the 11 beta-, 18- and 19-hydroxylations of 11-deoxycorticosterone, but not the aldosterone synthesis. P450(11 beta, aldo), on the other hand, catalyzes the conversion of 11-deoxycorticosterone to corticosterone, 18-hydroxycorticosterone and aldosterone. The two P450(11 beta)s were also shown to catalyze the conversion of 11-deoxycortisol to cortisol, 18-hydroxycortisol and cortisone.

Amino Acid Sequence↗