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Isamu Miyamori

Publications and source records attributed to Isamu Miyamori.

At least 19 recordsLinked to original sources
PubMed2006

Association of Gln222Arg polymorphism in the deoxyribonuclease I (DNase I) gene with myocardial infarction in Japanese patients.

AIMS: We have recently reported that serum deoxyribonuclease I (DNase I) activity, which may be involved in apoptosis, increases abruptly in the early phase of acute myocardial infarction (MI) [Kawai Y, Yoshida M, Arakawa K, Kumamoto T, Morikawa N, Masamura K, Tada H, Ito S, Hoshizaki H, Oshima S, Taniguchi K, Terasawa H, Miyamori I, Kishi K, Yasuda T. Diagnostic use of serum deoxyribonuclease I activity as a novel early-phase marker in acute myocardial infarction. Circulation 2004;109:2398-2400]. Death of vascular smooth muscle cells, in part because of apoptosis, is postulated to heighten susceptibility to disruption of vulnerable plaque, resulting in onset of MI. The present study evaluated the possibility that Gln222Arg polymorphism of the DNase I gene may be one of the factors involved in predisposition to MI. METHODS AND RESULTS: We assessed 611 Japanese patients: 311 with MI and 300 with stable angina pectoris (AP). Three common phenotypes determined by two common codominant alleles, DNASE1*1 and *2, whose corresponding gene products exhibit different properties, were found in these patient groups. The prevalence of DNASE1*2 was significantly higher in patients with MI than in those with AP (0.543 vs. 0.428, P < 0.001), being confirmed by phenotyping of the second study population. Multiple logistic regression analysis showed that the odds ratio of DNASE1*2 was 1.51 [95% confidence interval (CI) 1.04-2.18]. The association of the DNASE1*2 allele with MI was statistically significant, being independent of other conventional risk factors. CONCLUSION: Our data demonstrate that Gln222Arg polymorphism in the DNase I gene is associated with MI in the Japanese patients.

Aged↗
PubMed2006

[Pseudo aldosteronism].

Explore the source record for details and available documents.

11-beta-Hydroxysteroid Dehydrogenase Type 2↗
PubMed2006

Tissue gene expression of renin-angiotensin system in human type 2 diabetic nephropathy.

OBJECTIVE: Recent studies have proved that blockade of the renin-angiotensin system (RAS) retards the progression of diabetic nephropathy, whereas hyporeninemia is known as a typical state in diabetic subjects. The purpose of this study is to determine whether expression levels of RAS differ between nondiabetic and diabetic renal tissues with accurate quantitative method. RESEARCH DESIGN AND METHODS: Subjects were 66 nondiabetic and 8 diabetic patients with biopsy-proven renal diseases. The eight diabetic subjects suffered from type 2 diabetes with overt proteinuria. Renal histology revealed typical diffuse or nodular lesions with linear IgG deposit on immunofluorescent staining and thickened basement membrane on electronic microscopy. Total RNA from a small part of the renal cortical biopsy specimens was reverse-transcribed, and the resultant cDNA was amplified for new major components of RAS (i.e., renin, renin receptor, angiotensinogen, ACE, ACE2, angiotensin II type 1 receptor, and angiotensin II type 2 receptor) and measured. RESULTS: Among these components, a significant upregulation was observed in the ACE gene in diabetic renal tissue. CONCLUSIONS: The results suggest that renal tissue RAS might be activated in the respect that ACE gene expression is upregulated in spite of a tendency to low renin expression in type 2 diabetic nephropathy.

Adult↗
PubMed2006

Meningeal plasma cell granuloma with relapsing polychondritis. Case report.

Relapsing polychondritis (RP) is a rare systemic disease characterized by recurrent inflammation of the cartilaginous structures and connective tissue. Central nervous system lesions in association with RP have occasionally been reported, but intracranial mass lesions have not been described. The authors report the first such case, in which a 51-year-old man presented with parasagittal meningeal plasma cell granuloma with RP. The mass was subtotally resected and adjuvant radiotherapy was administered. The patient did not experience any recurrence of the lesion during an 8-year follow-up period. In this case, the exact diagnosis of RP was made based on symptoms of respiratory tract chondritis, which was successfully treated by the placement of tracheobronchial stents.

Granuloma, Plasma Cell↗
PubMed2005

Deficiency of the very low-density lipoprotein (VLDL) receptors in streptozotocin-induced diabetic rats: insulin dependency of the VLDL receptor.

Hyperlipidemia is a common feature of diabetes and is related to cardiovascular disease. The very low-density lipoprotein receptor (VLDL-R) is a member of the low-density lipoprotein receptor (LDL-R) family. It binds and internalizes triglyceride-rich lipoproteins with high specificity. We examined the etiology of hyperlipidemia in the insulin-deficient state. VLDL-R expression in heart and skeletal muscle were measured in rats with streptozotocin (STZ)-induced diabetes. STZ rats showed severe hyperlipidemia on d 21 and 28, with a dramatic decline in VLDL-R protein in skeletal muscle (>90%), heart (approximately 50%) and a loss of adipose tissues itself on d 28. The reduction of VLDL-R protein in skeletal muscle could not be explained simply by a decrease at the transcriptional level, because a dissociation between VLDL-R protein and mRNA expression was observed. The expression of LDL-R and LDL-R-related protein in liver showed no consistent changes. Furthermore, no effect on VLDL-triglyceride production in liver was observed in STZ rats. A decrease in postheparin plasma lipoprotein lipase activity started on d 7 and continued to d 28 at the 50% level even though severe hyperlipidemia was detected only on d 21 and 28. In rat myoblast cells, serum deprivation for 24 h induced a reduction in VLDL-R proteins. Insulin (10(-6) m), but not IGF-I (10 ng/ml), restored the decreased VLDL-R proteins by serum deprivation. These results suggest that the combination of VLDL-R deficiency and reduced plasma lipoprotein lipase activity may be responsible for severe hyperlipidemia in insulin-deficient diabetes.

Adipose Tissue↗
PubMed2005

Serum deoxyribonuclease I activity can be used as a sensitive marker for detection of transient myocardial ischaemia induced by percutaneous coronary intervention.

AIMS: Cardiac markers such as troponin T (c-TnT) have proven unsuitable for the detection of early and transient myocardial ischaemia. We recently reported that abrupt elevation of serum deoxyribonuclease I (DNase I) activity in the early stage of acute myocardial infarction could be used as a diagnostic marker. To evaluate whether serum DNase I could be used as a marker of early myocardial ischaemia, we investigated alterations in its levels after transient ischaemia induced during percutaneous coronary intervention (PCI). METHODS AND RESULTS: In 24 consecutive patients with stable angina undergoing elective PCI and 12 patients undergoing coronary angiography (CAG), serum samples were tested for DNase I, creatine kinase isoenzyme MB (CK-MB), and c-TnT before, soon after, and 3 and 12-24 h after completion of the procedures. Serum DNase I activity had risen significantly from baseline by 3 h after PCI in 21 of the 24 PCI patients. The mean per cent difference from baseline in serum DNase I activity 3 h after PCI was 35.9+/-37.5%. Even among the 16 PCI patients whose levels of CK-MB and c-TnT were within the normal range, 13 showed elevation of serum DNase I activity from baseline after PCI. In the CAG patient group, DNase I activity levels remained unchanged at all times after CAG. CONCLUSION: Elevation of serum DNase I activity can be used as a sensitive marker for detection of transient myocardial ischaemia.

Aged↗
PubMed2005

Interleukin-1beta attenuates beta-very low-density lipoprotein uptake and its receptor expression in vascular smooth muscle cells.

The very low-density lipoprotein (VLDL) receptor is a member of the low-density lipoprotein (LDL) receptor gene family with distinct tissue distribution and function. VLDL receptors are also expressed in vascular smooth muscle cells (VSMCs) and have been shown to be upregulated in atherosclerotic lesions. In the present study, we examined the effects of interleukin-1beta (IL-1beta) on the uptake of betaVLDL and its receptor expression in rat VSMCs. IL-1beta downregulated expression of the VLDL receptor in a time and dose-dependent manner as shown by Western blotting, Northern blotting, and reverse transcriptase-polymerase chain reaction (RT-PCR) analysis. Treatment with IL-1beta significantly reduced the uptake of beta-VLDL but not LDL in VSMCs. Use of specific pharmacologic inhibitors indicated that the tyrosine kinase inhibitors, herbimycin A and geldanamycin, completely reversed IL-1beta-induced downregulation of the VLDL receptor expression. Another tyrosine kinase inhibitor, genistein, the protein kinase C inhibitors, GF109203X and H7, the mitogen-activated protein (MAP) kinase inhibitors (MEK inhibitor PD098059 for [MEK] and SB203580 for p38-MAP kinase), and the protein kinase A inhibitor, KT5270 all had no effect on receptor expression. In addition, the c-Src specific inhibitor PP2 or adenoviral-mediated gene transfer of kinase inactive (KI)-c-Src failed to reverse IL-1beta-induced downregulation of VLDL receptor expression. These results indicate that IL-1beta attenuates uptake of VLDL through downregulation of its receptor in VSMCs, and that this downregulation is mediated through a benzoquinone ansamycin-dependent but c-Src-independent pathway.

Animals↗
PubMed2005

Reappraisal of clindamycin IV monotherapy for treatment of mild-to-moderate aspiration pneumonia in elderly patients.

BACKGROUND: As the number of elderly people has increased in Japan, the occurrence of aspiration pneumonia has also increased. Guidelines for the treatment of pneumonia have been proposed, in which the use of antibiotics, such as beta-lactam plus beta-lactamase inhibitor, clindamycin, and carbapenem, has been recommended as effective against anaerobic bacteria in the treatment of aspiration pneumonia. However, to our knowledge, a prospective comparison of these antibiotics regarding their clinical efficacy in aspiration pneumonia has not been performed. STUDY OBJECTIVES: We compared the effects of IV administration of a half dose of ampicillin/sulbactam (SBT/ABPC), normal dose of SBT/ABPC, IV clindamycin, and IV panipenem/betamiprom (PAPM/BP) for treatment of mild-to-moderate aspiration pneumonia in elderly patients. DESIGN: Randomized prospective study. PATIENTS: One hundred adult patients with compatible signs and symptoms of aspiration pneumonia. ASSESSMENTS: Patients were assessed before, during, and after treatment regarding symptoms, as well as results of laboratory values, chest radiograph examinations, and sputum bacterial cultures. RESULTS: We found few differences between the groups regarding cure rate, duration of IV medication, and occurrence of adverse effects with the tested therapies. However, clindamycin therapy was less expensive and was associated with a lower rate of posttreatment occurrence of methicillin-resistant Staphylococcus aureus. CONCLUSIONS: Clindamycin therapy for mild-to-moderate aspiration pneumonia is clinically effective, and provides economic advantages as compared to SBT/ABPC or PAPM/BP therapy.

Aged↗
PubMed2005

[A case of bilateral diaphragmatic paralysis clinically suggestive of brachial neuritis].

A 55-year-old man complained of acute onset of shoulder pain and dyspnea in the supine position. A diagnosis of bilateral diaphragmatic paralysis was made based on clinical inspection of his breathing pattern, radiographic appearance, and pulmonary function tests. He had had no traumatic or thoracic surgery or inflammatory episode. He did not suffer from diabetes, other central neural diseases, or any neoplastic disease. From the clinical feature and electromyographic findings, phrenic nerve involvement of brachial neuritis without any other muscle involvement was considered as a causative disease. When he received non-invasive intermittent positive-pressure ventilation by nasal mask in a supine position, his dyspnea was substantially attenuated and Carbon dioxide retention was lessened. After 1 year, his shoulder pain is still persisting and radiographic findings are not remarkably improved.

Brachial Plexus Neuritis↗
PubMed2004

Candidate cis-elements for human renin gene expression in the promoter region.

The regulation of renin gene expression, the rate-limiting enzyme of the system, is thought to be fundamental to the total system. Previously, we mapped six putative cis-elements in the promoter region of the human renin gene with nuclear proteins from human chorionic cells and human renal cortex by DNase I protection assay (footprint A-F). Each footprint contains Ets motif like site (A), HOXñPBX recognition sequence (B), unknown sequence as DNA binding consensus (C), CRE (D), COUP-TFII (ARP-1) motif like site (E), and AGE3 like site (F). Footprint D has been characterized by means of functional studies as the genuine human renin gene CRE interacting with CREB in cooperation with the site of footprint B. To obtain further clues to the specific expression in the promoter region, these putative cis-elements were conducted to a consensus-specific binding assay to compare renin-producing and non-renin-producing cells by EMSA and electromobility super-shift assay. Different sequence-specific DNA/protein binding was obtained among the different cell lines with footprint B site, with COUP-TFII (ARP-1) motif like site and possibly with footprint F site. The results implicate these putative cis-elements and each corresponding trans-factor in the specific expression of the human renin gene in the promoter region. Further functional characterization of these elements would provide important data for a better understanding of human renin gene expression.

Animals↗
PubMed2004

Diagnostic use of serum deoxyribonuclease I activity as a novel early-phase marker in acute myocardial infarction.

BACKGROUND: The delayed release of serum cardiac markers such as creatine kinase isoenzyme MB and equivocal early electrocardiographic changes have hampered a diagnosis of acute myocardial infarction (AMI) in the early phase after its onset. Therefore, a reliable serum biochemical marker for the diagnosis of AMI in the very early phase is desirable. METHODS AND RESULTS: Serum samples were collected from the patients with AMI, unstable angina pectoris, stable angina pectoris, and other diseases. Levels of serum deoxyribonuclease I (DNase I) activity in the patients were determined. An abrupt elevation of serum DNase I activity was observed within approximately 3 hours of the onset of symptoms in patients with AMI, with significantly higher activity levels (21.7+/-5.10 U/L) in this group compared with the other groups with unstable angina pectoris (10.4+/-4.41 U/L), angina pectoris (10.8+/-3.70 U/L), and other diseases (9.22+/-4.16 U/L). Levels of the DNase I activity in serum then exhibited a marked time-dependent decline within 12 hours and had returned to basal levels within 24 hours. CONCLUSIONS: We suggest that serum DNase I activity could be used as a new diagnostic marker for the early detection of AMI.

Adult↗