Search PubMed⌕ Search

Biomedical subjects

M Nakayama

Publications and source records attributed to M Nakayama.

At least 55 records · Page 3Linked to original sources
PubMed2001

Identification of three novel non-classical cadherin genes through comprehensive analysis of large cDNAs.

The terminal sequences of long cDNAs from human brains were subjected to an improved method of motif-trap screening. This process resulted in the identification of three novel genes that encode proteins with 27, 27, and six cadherin domains that we denoted as KIAA1773, KIAA1774 and KIAA1775, respectively. Sequence analysis indicated that the products of these genes were non-classical cadherins. KIAA1773 was found to be a mammalian homologue of the Drosophila dachsous gene but the remaining two genes did not have any likely homologues in public databases. Assessment of their expression in rat tissues indicated that these genes are expressed in highly distinct and tissue-specific patterns. Notably, KIAA1775 is expressed almost exclusively in the olfactory bulb in the rat brain. In situ hybridization further showed that KIAA1775 is strongly expressed by the mitral and tufted cells in the main and accessory olfactory bulbs, suggesting that KIAA1775 may be important in the formation and maintenance of neuronal networks, particularly those in the olfactory bulb. This study clearly shows the importance and usefulness of our cDNA project in search for genes encoding large proteins, as this project has allowed us to identify several novel non-classical cadherin genes that have thus far not been detected by conventional methods.

Amino Acid Sequence↗
PubMed2001

Aldosterone induces angiotensin-converting-enzyme gene expression in cultured neonatal rat cardiocytes.

BACKGROUND: The cardiac renin-angiotensin-aldosterone system is activated in failing hearts in proportion to the severity of the disease. We hypothesized that a positive feedback mechanism might exist within this system and contribute to the progression of the heart failure. Methods and Results-- To test this hypothesis, we examined whether angiotensin II or aldosterone induces the expression of angiotensin-converting-enzyme (ACE) mRNA in cultured neonatal rat ventricular cardiocytes. Expression of ACE mRNA was detected and quantified using real-time reverse transcription-polymerase chain reaction. Exposure to angiotensin II (10(-5) mol/L) for 24 hours had no significant effect on the expression of ACE mRNA (0.7+/-0.5-fold versus control, P=NS), but similar treatment with aldosterone (10(-5) mol/L) induced a 23.3+/-7.9-fold increase (P<0.01) in ACE mRNA expression. The effect of aldosterone was both time- (maximal effect, 24 hours) and dose-dependent (EC(50), 4x10(-7) mol/L), and it was significantly (P<0.01) inhibited by spironolactone, a specific mineralocorticoid receptor antagonist. CONCLUSIONS: Aldosterone upregulates ACE mRNA expression, which is blocked by spironolactone in neonatal rat cardiocytes. Thus, spironolactone may suppress the progression of heart failure by blocking the effects of aldosterone and angiotensin II.

Aldosterone↗
PubMed2001

Specific recognition of cytosolic thymidine kinase in the human lung tumor by monoclonal antibodies raised against recombinant human thymidine kinase.

Anti-TK monoclonal antibodies (mAbs) were raised against recombinant human cytosolic thymidine kinase (rhTK) and characterized by Western immunoblotting, enzyme-linked immunosorbent assay (ELISA) and immunostaining of tumor cells. Twenty-three clones of TK mAbs were characterized to recognize specifically not only rhTK produced by Escherichia coli but also TK subunit of 25 kDa in human lung cancer. The anti-TK mAbs reacted specifically with cytosolic TK but not with mitochondrial TK. Only one clone of the mAbs inhibited the catalytic activity of TK. By solid phase sandwich enzyme immunoassay using these mAbs, we could quantitate the cytosolic TK content in tissues. Immunohistochemical staining analysis using one of the TK mAbs showed that human lung adenocarcinoma and squamous cell carcinoma exhibited much higher staining intensity than stromal cells. These mAbs are useful for biochemical studies on the regulation of human TK in proliferating cells such as tumor cells and for diagnosis of highly proliferating tumors.

Adenocarcinoma↗
PubMed2001

Prediction of the coding sequences of unidentified human genes. XX. The complete sequences of 100 new cDNA clones from brain which code for large proteins in vitro.

To accumulate information on the coding sequences of unidentified genes, we have carried out a sequencing project of human cDNA clones which encode large proteins. We herein present the entire sequences of 100 cDNA clones of unidentified human genes, named KIAA1776 and KIAA1780-KIAA1878, from size-fractionated cDNA libraries derived from human fetal brain, adult whole brain, hippocampus and amygdala. Most of the cDNA clones to be entirely sequenced were selected as cDNAs which were shown to have coding potentiality by in vitro transcription/translation experiments, and some clones were chosen by using computer-assisted analysis of terminal sequences of cDNAs. Three of these clones (fibrillin2/KIAA1776, MEGF10/KIAA1780 and MEGF11/KIAA1781) were isolated as genes encoding proteins with multiple EGF-like domains by motif-trap screening. The average sizes of the inserts and corresponding open reading frames of eDNA clones analyzed here reached 4.7 kb and 2.4 kb (785 amino acid residues), respectively. From the results of homology and motif searches against the public databases, the functional categories of the predicted gene products of 54 genes were determined; 93% of these predicted gene products (50 gene products) were classified as proteins related to cell signaling/communication, nucleic acid management, or cell structure/motility. To collect additional information on these genes, their expression profiles were also studied in 10 human tissues, 8 brain regions, spinal cord, fetal brain and fetal liver by reverse transcription-coupled polymerase chain reaction, products of which were quantified by enzyme-linked immunosorbent assay.

Adult↗
PubMed2001

Role of PKC and TGF-beta receptor in glucose-induced proliferation of smooth muscle cells.

The role of protein kinase C (PKC) and transforming growth factor (TGF)-beta in the proliferation of vascular smooth muscle cells (SMCs) under a high glucose condition was investigated. [3H]-thymidine incorporation under 20 mM glucose was significantly accelerated compared with that under 5.5 mM glucose, and this increase was inhibited by an anti-TGF-beta antibody or a PKC-beta specific inhibitor, LY333531. The amount of active and total TGF-beta1 in the conditioned media did not differ between 5.5 and 20 mM glucose. However, the expression of TGF-beta receptor type II under 20 mM glucose was significantly increased, but that of the TGF-beta receptor type I was not. This increased expression of the TGF-beta receptor type II was prevented by LY333531. These observations suggest that the increased expression of the TGF-beta receptor type II via PKC-beta plays an important role in the accelerated proliferation of SMCs under a high glucose condition, leading to the development of diabetic macroangiopathy.

Activin Receptors, Type I↗
PubMed2001

The 70-kDa major DNA-compacting protein of the chloroplast nucleoid is sulfite reductase.

The chloroplast nucleoid is a complex of chloroplast DNA and various, mostly uncharacterized proteins. An abundant 70-kDa protein of the isolated nucleoids of pea chloroplasts was identified as sulfite reductase by N-terminal sequence analysis as well as immunoblot analysis, spectrophotometry and enzyme activity analysis. Recombinant maize sulfite reductase was indeed able to compact chloroplast DNA and to form nucleoid-like particles in vitro. The role of sulfite reductase in the structural organization of the nucleoid is discussed.

Amino Acid Sequence↗
PubMed2001

Aldosterone production is activated in failing ventricle in humans.

BACKGROUND: Recent reports have indicated that aldosterone is produced in extra-adrenal tissues in animals. The present study was designed to examine whether aldosterone is produced in human heart. METHODS AND RESULTS: Plasma levels of aldosterone, BNP, and angiotensin-converting enzyme were measured in anterior interventricular vein (AIV), coronary sinus (CS), and aortic root (Ao), respectively, in 20 patients with left ventricular systolic dysfunction (LVSD), 25 patients with LV diastolic dysfunction (LVDD), and 23 control subjects. Aldosterone levels were significantly higher in AIV and CS than Ao in LVSD (98+/-10 versus 72+/-9 pg/mL, P:<0.001, and 97+/-11 versus 72+/-9 pg/mL, P:<0.001, respectively) and LVDD (87+/-10 versus 71+/-9 pg/mL, P:<0.01, and 84+/-10 versus 71+/-9 pg/mL, P:<0.01, respectively) groups, but no differences were observed in levels for these sites in the control group. Levels of ACE activity and BNP also were higher in AIV than Ao in both LV dysfunction groups. The difference in aldosterone levels between AIV and Ao and those in BNP and angiotensin-converting enzyme had a significant positive correlation with LVEDP and a significant negative correlation with LV ejection fraction in the LVSD group. CONCLUSIONS: Production of aldosterone, angiotensin-converting enzyme, and BNP are activated in failing human ventricle in proportion to severity.

Adult↗
PubMed2001

Observation of untreated patients with neuroblastoma detected by mass screening: a "wait and see" pilot study.

BACKGROUND: Recent studies have indicated that mass screening for neuroblastoma detects tumors that otherwise would have regressed spontaneously without recognition. Therefore, we started an observation program for these patients to determine how frequently spontaneous regression occurs. PROCEDURE: Eighteen patients were detected by mass screening between June 1994 and December 1996. Eight of these cases matched the following criteria and entered the observation program: Stage I or II, less than 5 cm in diameter; no involvement of large vessels or organs; not difficult to resect; informed consent. If there were an increase in tumor size, an elevation of tumor markers, or evidence of metastasis, the tumor would be immediately resected. RESULTS: Five of the eight cases showed spontaneous regression. Although the remaining three tumors were resected 6-10 months after diagnosis, all patients survived without evidence of recurrence. CONCLUSIONS: At least 60% of neuroblastoma cases who entered our observation program regressed spontaneously.

Adrenal Gland Neoplasms↗
PubMed2001

Eight novel mutations of the FBN1 gene found in Japanese patients with Marfan syndrome.

Marfan syndrome (MFS), an autosomal dominant connective tissue disorder, is caused by mutations in the gene encoding fibrillin 1 (FBN1). The clinical spectrum and severity of MFS disorder varies greatly both between and within families. Since there have been only a few reports on the relationship between FBN1 genotypes and clinical phenotypes in Japanese patients, the FBN1 gene was analyzed in 27 Japanese patients diagnosed with MFS. The nucleotide sequence of the 65 exons of the FBN1 gene was analyzed by PCR and direct sequencing. We have identified six polymorphisms and nine mutations including: four missense mutations (C1652Y, Q2054P, D2127Y, C2221R) in six patients, three nonsense mutations (R215X, S813X, R2220X) in three patients, and two frameshift mutations (2567insT, 7790insT) in three patients. Six of these nine mutations were in the calcium-binding epidermal growth factor-like domains all causative mutations detected except for C2221R were novel. It has been reported that the severe phenotypes of infantile MFS correlate with mutations in the mid region of FBN1, however, mutations were not detected in this region in the population analyzed in this study. Our results suggest that the location of the mutation is not the sole determinant of phenotypic severity; rather there is some difference in the genetic basis of MFS between Japanese and Caucasian populations.

Adolescent↗
PubMed2001

Values of the bispectral index do not parallel the hemodynamic response to the rapid increase in isoflurane concentration.

PURPOSE: To investigate the changes in hemodynamic variables and bispectral index (BIS) in response to a rapid increase in isoflurane or sevoflurane concentration. METHOD: Thirty adult patients were anesthetized with either isoflurane (isoflurane group) or sevoflurane (sevoflurane group). Two minutes after induction of anesthesia with thiamylal, the inspired concentrations of isoflurane and sevoflurane were rapidly increased from 0.5 minimum alveolar anaesthetic concentration (MAC) to 3 MAC and maintained for five minutes. Heart rate (HR), mean arterial pressure (MAP), and BIS were measured every minute. RESULTS: An increase in the anesthetic concentration caused increases in HR and MAP in the isoflurane group and a decrease in MAP in the sevoflurane group. Consequently, HR and MAP in the isoflurane group were significantly higher than those in the sevoflurane group. After inhalation of high concentrations, BIS significantly and progressively decreased in both groups. CONCLUSION: BIS values decrease after a step increase in volatile agent concentration, whether or not a hyperdynamic action occurs.

Adult↗
PubMed2001

Perioperative intravenous flurbiprofen reduces postoperative pain after abdominal hysterectomy.

PURPOSE: To assess whether perioperative intravenous administration of flurbiprofen, a non-steroidal anti-inflammatory drug, reduced postoperative pain after abdominal hysterectomy. METHODS: Forty-five patients undergoing abdominal hysterectomy were randomly assigned to one of three groups of equal size. A control group (CONT) received a placebo 30 min before and at the end of surgery. The other two groups, PRE and POST, received 1 mg x kg(-1) flurbiprofen iv 30 min before and at the end of surgery, respectively. All patients received identical general and epidural anesthesia. Postoperatively, 50 mg diclofenac pr was given for pain relief on patient demand. One of the authors assessed pain using a 10 cm visual analog scale at rest and during coughing at the first request for diclofenac, and at 15, 24, 48, and 72 hr after surgery. The number of times diclofenac was required during the first 24 hr after surgery was also recorded. RESULTS: The number of diclofenac requests in the PRE (1.8 +/- 0.4) and POST groups (2.0 +/- 0.4) were less than in the CONT group (3.0 +/- 0.4). The PRE group showed lower visual analog scale at rest at 15 and 24 hr and on coughing at 24, 48, and 72 hr after surgery than the CONT and POST groups. CONCLUSION: Intravenous 1 mg x kg(-1) flurbiprofen administered during anesthesia reduces postoperative rescue analgesic requirement after abdominal hysterectomy. Moreover, flurbiprofen is more effective when given before than after surgery.

Adult↗
PubMed2001

Elevated KL-6 levels in fatal measles pneumonia.

We measured KL-6 concentrations in serum samples from measles patients with various forms of pneumonia and abnormally elevated levels of KL-6 were found exclusively in four fatal cases of pulmonary insufficiency.

Adolescent↗
PubMed2001

Efficacy of alkalinized lidocaine for reducing pain on intravenous and epidural catheterization.

PURPOSE: To investigate whether increasing the pH of lidocaine could reduce the pain caused by its skin infiltration as well as that caused by intravenous and epidural needle insertion. METHODS: A randomized, double-blind trial was undertaken in patients who were allocated to receive topical anesthesia with either plain (plain group; n = 25) or alkalinized lidocaine (alkalinized group; n = 25). An alkalinized lidocaine solution was prepared by adding 8.4% sodium bicarbonate to a plain 1% lidocaine solution at a ratio of 1 : 10. Pain was assessed using the verbal analog scale (VAS). RESULTS: In the alkalinized group, the VAS scores on skin infiltration in the hand (2.5 +/- 1.4) and the back (2.7 +/- 1.4) were significantly lower than the respective scores in the plain group (3.5 +/- 1.4, and 4.9 +/- 1.9). Although the VAS score on intravenous needle insertion did not differ between the two groups, the VAS score on epidural needle insertion was significantly lower in the alkalinized group (1.3 +/- 1.0) than in the plain group (3.6 +/- 1.3). CONCLUSIONS: Alkalinization of lidocaine was effective in attenuating pain on skin infiltration and on epidural needle insertion.

Clinical Trial↗
PubMed2001

Hammerhead ribozyme targeting human platelet-derived growth factor A-chain mRNA inhibited the proliferation of human vascular smooth muscle cells.

Platelet-derived growth factor (PDGF) A-chain contributes to the pathogenesis of cardiovascular proliferative diseases, such as hypertensive vascular disease, atherosclerosis, and re-stenosis of an artery after angioplasty. To develop a ribozyme against human PDGF A-chain mRNA as a gene therapy for human arterial proliferative diseases, we designed and synthesized a 38-base hammerhead ribozyme to cleave human PDGF A-chain mRNA at the GUC sequence at nucleotide 591. In the presence of MgCl(2), synthetic hammerhead ribozyme to human PDGF A-chain mRNA cleaved the synthetic target RNA to two RNA fragments at a predicted size. Doses of 0.01-1.0 microM hammerhead ribozyme to human PDGF A-chain mRNA significantly inhibited angiotensin II (Ang II) and transforming growth factor (TGF)-beta(1)-induced DNA synthesis in vascular smooth muscle cells (VSMC) from human in a dose-dependent manner. One micromolor of hammerhead ribozyme to human PDGF A-chain mRNA significantly inhibited Ang II-induced PDGF A-chain mRNA and PDGF-AA protein expressions in VSMC from humans. These results indicate that the designed hammerhead ribozyme to human PDGF A-chain mRNA effectively inhibited growth of human VSMC by cleaving the PDGF A-chain mRNA and inhibiting the PDGF-AA protein expression in human VSMC. This suggests that the designed hammerhead ribozyme to PDGF A-chain mRNA is a feasible gene therapy for treating arterial proliferative diseases.

Arterial Occlusive Diseases↗
PubMed2001

Endogenous gibberellins in immature seeds of Prunus persica L.: identification of GA(118), GA(119), GA(120), GA(121), GA(122) and GA(126).

The endogenous gibberellins in immature seeds of Prunus persica were analyzed by gas chromatography-mass spectrometry. Eleven known gibberellins, GA(3), GA(9), GA(17), GA(19), GA(30), GA(44), GA(61), GA(63), GA(87), GA(95) and GA(97) were identified. Additionally, several hitherto unknown gibberellins were detected and their putative structures were verified by synthesis of the authentic gibberellins. These gibberellins were then assigned trivial numbers, e.g. 1alpha-hydroxy GA(20) (GA(118)), 1alpha-hydroxy GA(9) (GA(119)), 1,2-didehydro GA(9) (GA(120)), 1,2-didehydro GA(70) (GA(121)), 1,2-didehydro GA(69) (GA(122)) and 1,2-didehydro GA(77) (GA(126)). GA(118) and GA(119) were the first 1alpha-hydroxy gibberellins identified from higher plants. The above profile of 1,2-didehydro gibberellins suggests that 1,2-dehydrogenation might occur prior to 3beta-hydroxylation in biosynthesis of GA(3), GA(30) and GA(87) in immature seeds of P. persica.

Gas Chromatography-Mass Spectrometry↗
PubMed2001

Differential expression of adrenomedullin and its receptor component, receptor activity modifying protein (RAMP) 2 during hypoxia in cultured human neuroblastoma cells.

Adrenomedullin is a potent vasodilator peptide originally isolated from a pheochromocytoma. Recently, a novel adrenomedullin receptor has been identified as a complex consisting of calcitonin receptor-like receptor (CRLR) and receptor activity modifying protein (RAMP) 2. To explore possible pathophysiological roles of adrenomedullin and its receptor component RAMP2 in hypoxic tissues, we studied effects of hypoxia on expression of adrenomedullin and RAMP2 in two human neuroblastoma cell lines, IMR-32 and NB69, by radioimmunoassay and Northern blot analysis. Expression levels of adrenomedullin were increased by hypoxia in both cell lines. Treatment with cobalt chloride or desferrioxamine mesylate also increased expression levels of adrenomedullin mRNA. On the other hand, expression levels of RAMP2 mRNA were decreased in IMR-32 cells and were not changed in NB69 cells by hypoxia. Treatment with cobalt chloride or desferrioxamine mesylate decreased expression levels of RAMP2 mRNA in both IMR-32 and NB69 cells. These findings indicate that adrenomedullin expression is induced during hypoxia in IMR-32 and NB69 neuroblastoma cells, but RAMP2 expression is rather suppressed under the same conditions. The decreased expression of RAMP2 and the ADM expression induction under hypoxia may constitute one mechanism of cellular adaptation to hypoxic stress.

Adrenomedullin↗
PubMed2001

Antinociceptive effect of spinally injected L-NAME on the acute nociceptive response induced by low concentrations of formalin.

The formalin test has been proposed as an animal model of pain produced by tissue injury. Although biphasic nociceptive responses to formalin injection have been well documented, low concentrations (0.125 and 0.5%) of formalin injected into the mouse hindpaw produced only the phasic (acute) paw-licking response, lasting the first 5 min after the formalin injection. To explore the involvement of nitric oxide (NO) in the spinal cord and peripheral system during the acute phase of the formalin test, we examined the effect of intrathecal (i.t.) or intraplantar (i.pl.) injection of L-N(G)-nitro arginine methyl ester (L-NAME), a NO synthase inhibitor in mice. Pretreatment with L-NAME (160 nmol), injected i.t., resulted in a significant inhibition of the paw-licking response induced by 0.125 and 0.5% of formalin. L-Arginine (600 mg/kg, i.p.) but not D-arginine (600 mg/kg, i.p.) reversed the antinociceptive effect of L-NAME on the acute nociceptive response induced by low concentrations of formalin. The i.pl. injection of L-NAME (160 nmol) produced a significant decrease of the late (tonic) phase response evoked by 2.0% formalin without affecting the early (acute) phase response. Similar results have been reported in the case of i.t. injected L-NAME as assayed by the 2.0% formalin test. L-NAME (160 nmol), injected into the plantar paw, gave no significant effect on the acute nociceptive response induced by a low concentration of formalin (0.125%). These results suggest that NO in the spinal cord may be involved in not only the late phase response of the formalin (2.0%)-induced paw-licking, but also at least the acute phase response induced by low concentrations (0.125 and 0.5%) of formalin, while peripheral NO has little effect on the early (acute) phase nociceptive response evoked by formalin (0.125--2.0%) injection.

Analgesics↗