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Biomedical subjects

M Shimizu

Publications and source records attributed to M Shimizu.

At least 55 records · Page 3Linked to original sources

Restenosis of the sigmoid sinus after stenting for treatment of intracranial venous hypertension: case report.

We report what we believe to be the first case of restenosis of the sigmoid sinus after stenting, in a 42-year-old man with an arteriovenous malformation with progressive right hemiparesis secondary to venous hypertension. Angiography revealed severe stenosis of the left sigmoid sinus, which was dilated with a self-expandable stent. Six months after the procedure, however, the sinus was again severely stenosed. Intravascular sonography revealed intimal proliferation in the stented sinus. It was dilated percutaneously, and the venous pressure decreased from 51 to 33 mmHg. On sonography, the intimal tissue decreased in thickness and the diameter of the stent enlarged a little.

Adult↗

Inter--rater and test--retest reliability of the Japanese version of the subjective deficit syndrome scale.

The subjective deficit syndrome scale (SDSS) was established in 1990 by Jaeger et al. to assess systematically subjective experiences of schizophrenic patients. It was translated into Japanese in 1999 by this paper's second author (T.I.). In this study, the inter-rater reliability of this Japanese version (SDSS-J) was examined. The subjects studied were 13 schizophrenic patients (male 6, female 7; respective average ages at study entry and disease onset: 41 and 25 years), who were being followed up at the outpatients' service of the Department of Neuropsychiatry, Hyogo College of Medicine. Four psychiatrists attended together, the systematic interview with each subject to rate the SDSS-J and independently rated 19 items. The severity scales of the items assessed by these raters ranged from 0 to 4 for 12 items and from 0 to 3 for 7. The ANOVA ICC inter-rater reliability values for the 19 individual items ranged from 0.67 to 0.96. The ANOVA ICC test-retest reliability values achieved by two raters were also high overall, ranging from 0.72 to 1.00, except for one item (item 13) assessed by one rater. Our results suggest that the SDSS-J is a potentially useful rating scale for evaluating subjective experiences of schizophrenic subjects.

Adolescent↗

Inhibition of NFkappaB activation using cis-element 'decoy' of NFkappaB binding site reduces neointimal formation in porcine balloon-injured coronary artery model.

Application of DNA technology to regulate the transcription of disease-related genes has important therapeutic potential. The transcription factor NFkappaB plays a pivotal role in the transactivation of inflammatory and adhesion molecule genes, leading to vascular lesion formation. Double-stranded DNA with high affinity for NFkappaB may be introduced as 'decoy' cis elements to bind NFkappaB and block the activation of genes mediating inflammation, resulting in effective drugs for treating intimal hyperplasia. In this study, we tested the feasibility of NFkappaB decoy therapy to treat neointimal formation in a porcine coronary artery balloon injury model as a pre-clinical study. An angioplasty catheter was introduced into the left anterior descending coronary artery of the pig to cause vascular injury. First, we tested the feasibility of transfection of FITC-labeled NFkappaB decoy ODN using a hydrogel balloon catheter. Fluorescence due to NFkappaB decoy ODN could be detected throughout the medial layer. Therefore, we transfected NFkappaB decoy ODN into the balloon-injured LAD using a hydrogel catheter. Histological evaluation demonstrated that the neointimal area in the balloon-injured artery was significantly reduced by NFkappaB decoy ODN as compared to scrambled decoy ODN at 1 week after single transfection, accompanied by a significant reduction in PCNA-positive stained cells (P < 0.01). Interestingly, the reduction of ICAM-positive staining was observed, accompanied by the inhibition of migration of macrophages. Of importance, intravascular ultrasound (IVUS) confirmed that neointimal area in the balloon-injured artery was significantly reduced by NFkappaB decoy ODN at 4 weeks after transfection (P < 0.01). Interestingly, the inhibition of neointimal area was only limited to the lesion transfected with NFkappaB decoy ODN, while other lesions without NFkappaB decoy ODN demonstrated a marked increase in neointimal formation. Here, we report the successful in vivo transfer of NFkappaB decoy ODN using a hydrogel catheter to inhibit vascular lesion formation in balloon-injured porcine coronary artery.

Angioplasty, Balloon, Coronary↗

An international study of the performance of sample collection from patients.

BACKGROUND AND OBJECTIVES: Collection of a blood sample from the correct patient is the first step in the process of safe transfusion. The aim of this international collaborative study was to assess the frequency of mislabelled and miscollected samples drawn for blood grouping. MATERIALS AND METHODS: Hospitals in 10 countries provided data on sample error rates during a period of at least 3 months, including the last quarter of 2001. Mislabelled samples were defined as those not meeting local criteria for acceptance by the laboratory. Miscollected samples [wrong-blood-in-tube (WBIT)] were defined as samples in which the blood group result differed from the result on file from prior testing. WBIT rates were corrected for the proportion of repeat samples and for undetectable errors occurring as a result of chance collection of blood from the wrong patient with the same ABO group. Participants also completed a questionnaire on current policies regarding sample collection. RESULTS: A total of 71 hospitals completed surveys describing policies related to sample collection. Sixty-two hospitals provided usable data on the frequency of mislabelled and miscollected samples. Mislabelled and miscollected samples were common. Based on results from over 690,000 samples, the median hospital performance resulted in a rate for mislabelling of 1 in every 165 samples (6.1 per 1000; interquartile range 1.2-17 per 1000). The presence of national patient identification systems in Sweden and Finland was associated with rates of miscollected samples that were too low to estimate. Outside these nations, miscollected samples demonstrating WBIT occurred at a median rate of 1 in every 1986 samples (0.5 per 1000; interquartile range <0.3-0.9 per 1000). There was great variation worldwide in the reported frequency of mislabelled samples, probably resulting from variation in policies for sample acceptance. Miscollected samples occurred at a more constant rate. CONCLUSIONS: The rate of mislabelled samples and miscollected samples is 1000-10,000-fold more frequent than the risk of viral infection. Rates of mislabelled samples and WBIT can be tracked as key indicators of performance of an important step in the clinical transfusion process. WBIT episodes represent important 'near-miss' errors. By providing baseline performance data for the collection of patient blood samples, this study may be useful in formulating future national standards of performance for sample collection from patients.

Blood Group Incompatibility↗

Clinical evaluation of pioglitazone in patients with type 2 diabetes using alpha-glucosidase inhibitor and examination of its efficacy profile.

AIM: Pioglitazone is considered to reduce insulin resistance. This study was conducted to evaluate the efficacy, safety and clinical profile of pioglitazone in patients whose type 2 diabetes were poorly controlled with alpha-glucosidase inhibitor alone or alpha-glucosidase in combination with sulfonylurea. METHODS: Twenty patients with type 2 diabetes were treated with pioglitazone (30 mg q.d.) orally for 16 weeks. RESULTS: There were significant reductions in HbA1C, FPG and postprandial plasma glucose at week 16. As adverse events, oedema, hypoglycaemia-like reaction, increases in LDH, CPK, etc. were noted. There was no significant change in TNF-alpha. Leptin levels increased significantly at week 16 and were still increasing 4 weeks after the treatment. Per cent body fat was almost constant throughout the study period. When efficacy was classified by demographic variables, pioglitazone was found to be more effective in the subjects who had a higher postprandial 2-h plasma glucose level, leptin level or per cent body fat value. CONCLUSION: Pioglitazone was considered to be effective when used in patients whose type 2 diabetes were poorly controlled with alpha-glucosidase inhibitor alone or alpha-glucosidase in combination with sulfonylurea.

Adult↗

Surgical correction of cor triatriatum dexter in a dog under extracorporeal circulation.

A shiba inu dog with marked abdominal distension was diagnosed with cor triatriatum dexter and surgical correction was performed under extracorporeal circulation. The total duration of cardiac arrest was 11 minutes and total perfusion time was 34 minutes. The dog had an uneventful postoperative recovery. Postoperative contrast radiography of the caudal vena cava revealed normal flow into the right heart. Abdominal distension was no longer observed. Although several methods have been used to treat cor triatriatum dexter in dogs, the authors consider surgical correction under extracorporeal circulation to be a reliable approach.

Animals↗

QT dispersion and left ventricular morphology in patients with hypertrophic cardiomyopathy.

OBJECTIVE: To evaluate the relation between QT variables and disproportion of left ventricular wall hypertrophy in patients with hypertrophic cardiomyopathy. DESIGN: Retrospective analysis of the results of echocardiography and electrocardiography. SETTING: University hospital (tertiary referral centre). PATIENTS: 70 patients with hypertrophic cardiomyopathy were divided into four groups according to the distribution of left ventricular wall hypertrophy on cross sectional echocardiography: group A--hypertrophy confined to the interventricular septum; group B--hypertrophy confined to the interventricular septum and left ventricular anterior wall; group C--hypertrophy confined to the interventricular septum, left ventricular anterior wall, and lateral free wall; group D--hypertrophy involving all portions of the left ventricle. MAIN OUTCOME MEASURES: QT intervals and QT dispersion in precordial six lead ECGs. RESULTS: There were no significant differences in the maximum left ventricular wall thickness among the four groups, and maximum and minimum QTc intervals also did not differ. QTc dispersion was increased significantly in groups A and B compared with groups C and D. Dispersions of the interval from the J point to the end of the T wave (JTc dispersions) in groups A and B were also increased significantly compared with groups C and D. By linear regression analysis, QTc and JTc dispersions correlated with the ratio of the interventricular septal thickness to left ventricular posterior wall thickness (p = 0.0152 and p = 0.0075, respectively). CONCLUSIONS: QT dispersion may be affected by not only electrical inhomogeneity but also by morphological inhomogeneity of the left ventricle in patients with hypertrophic cardiomyopathy.

Adult↗

Development of an RIA for salmon 41 kDa IGF-binding protein.

Salmon plasma contains at least three IGF-binding proteins (IGFBPs) with molecular masses of 41, 28 and 22 kDa. The 41 kDa IGFBP is similar to mammalian IGFBP-3 in size, type of glycosylation and physiological responses. In this study, we developed an RIA for the 41 kDa IGFBP. The 41 kDa IGFBP purified from serum was used for antibody production and as an assay standard. Binding of three different preparations of tracer were examined: (125)I-41 kDa IGFBP, (125)I-41 kDa IGFBP cross-linked with IGF-I and 41 kDa IGFBP cross-linked with (125)I-IGF-I (41 kDa IGFBP/(125)I-IGF-I). Only binding of 41 kDa IGFBP/(125)I-IGF-I was not affected by added IGFs, and therefore it was chosen for the tracer in the RIA. Plasma 41 kDa IGFBP levels measured by RIA were increased by GH treatment (178.9+/-4.9 ng/ml) and decreased after fasting (95.0+/-7.0 ng/ml). The molarities of plasma 41 kDa IGFBP and total IGF-I were comparable, and they were positively correlated, suggesting that salmon 41 kDa IGFBP is a main carrier of circulating IGF-I in salmon, as is mammalian IGFBP-3 in mammals. During the parr-smolt transformation (smoltification) of coho salmon, plasma 41 kDa IGFBP levels showed a transient peak (182.5+/-10.3 ng/ml) in March and stayed relatively constant thereafter, whereas IGF-I showed peak levels in March and April. Differences in the molar ratio between 41 kDa IGFBP and IGF-I possibly influence availability of IGF-I in the circulation during smoltification.

Animals↗

[Spinal cord ischemia complicated with acute aortic dissection and intramural hematoma; report of two cases].

Spinal cord ischemic injury is one of te most serious complications in patients with aortic dissection. We experienced 2 cases with severe upper back pain and paraplegia of the lower extremities as initial manifestations of acute DeBakey type IIIb aortic dissection (case 1) and aortic intramural hematoma (IMH) from ascending aorta to abdominal aorta (case 2). Paraplegia was permanent and spinal cord atrophy was proved at Th 9-10 by the magnetic resonance imaging (MRI) in case 1. The aortic IMH regressed rapidly and paraplegia was transient in case 2. The MRI obtained 18 days after the onset showed scattered small lesions within the spinal cord at Th 4-7.

Adult↗

Effect of alumina femoral heads on polyethylene wear in cemented total hip arthroplasty. Old versus current alumina.

We examined the behaviour of alumina ceramic heads in 156 cemented total hip arthroplasties, at a minimum follow-up of eight years. They were divided into three groups according to the size of the femoral head; 22, 26, and 28 mm. We measured polyethylene wear radiologically using a computer-aided technique. The linear wear rate of polyethylene sockets for the 28 mm heads was high (0.156 mm/year), whereas those for the 22 and 26 mm heads were relatively low (0.090 and 0.098 mm/year, respectively). Moreover, the surface roughness data of retrieved femoral heads clearly showed maintenance of an excellent surface finish of the current alumina. We conclude that the alumina ceramic femoral heads currently used are associated with a reduced rate of polyethylene wear.

Adult↗

Candida septic arthritis of the hip in a young patient without predisposing factors.

We present a case of septic arthritis of the hip caused by Candida albicans in a 24-year-old woman. This is the first report of a Candida infection of the hip in a patient without any predisposing factors. She underwent a two-stage total hip arthroplasty three years after the onset of the infection. An elevated plasma level of beta-D-glucan suggested Candida as the infecting organism and the diagnosis might have been made earlier if this test had been undertaken at presentation.

Adult↗

Expression of cyclooxygenase-2 in human hyperplastic gastric polyps.

Cyclooxygenase (COX)-2, an inducible isoform of prostaglandin synthetase, has been reported to be a key molecular target of colon cancer prevention by nonsteroidal anti-inflammatory drugs. Recently, it has been shown that Helicobacter pylori (H. pylori) could induce COX-2 together with inflammatory cytokines. Although human hyperplastic gastric polyps disappeared or decreased in number and size after eradication of H. pylori, the mechanisms in this step, especially the roles of COX-2, have not been yet elucidated. The aims of the present study were to examine the expression and localization of COX-2 in human hyperplastic gastric polyps immunohistochemically. Twelve specimens of human hyperplastic gastric polyps were obtained from endoscopic polypectomy. The expression of the COX-2 protein was immunohistochemically examined on formalin-fixed and paraffin-embedded tissue sections using an anti-COX-2 antibody and an avidin-biotin complex method. Cells expressing COX-2 were further immunohistochemically identified using a specific antibody against macrophages (CD68), and myofibroblasts (alpha-smooth muscle actin). Immunoreactive COX-2 was predominantly and strongly expressed in interstitial cells in the sub-epithelial layer of 10 hyperplastic polyps. Semi-quantitative analysis revealed a significant increase in COX-2 expression in interstitial cells. The staining pattern of macrophages and myofibroblasts partly corresponded to that observed for COX-2 in hyperplastic gastric polyps. These results suggest that COX-2 in mesenchymal cells induced by H. pylori may play an important role in the tumorigenesis of human hyperplastic gastric polyps.

Aged↗

High insulin enhances neutrophil transendothelial migration through increasing surface expression of platelet endothelial cell adhesion molecule-1 via activation of mitogen activated protein kinase.

AIMS/HYPOTHESIS: There is increasing evidence that hyperinsulinaemia is linked with the development of atherosclerosis in patients with diabetes. However, the mechanisms by which hyperinsulinaemia causes accelerated atherosclerosis, especially with respect to leukocytes transendothelial migration, are poorly understood. We examined whether hyperinsulinaemia directly affects neutrophil transendothelial migration and surface expression of related endothelial adhesion molecules. METHODS: Experiments on the transmigration of neutrophils from healthy volunteers and from patients with Type II (non-insulin-dependent) diabetes mellitus across human umbilical vein endothelial cells cultured in insulin-rich medium using cell-culture inserts were carried out. Migrated neutrophils were quantified by measuring their myeloperoxidase activities, and the surface expression of endothelial adhesion molecules was examined using an enzyme immunoassay. RESULTS: High insulin (over 50 microU/ml for 24 h) enhanced neutrophil transendothelial migration in a dose-dependent manner. This was associated with increased expression of platelet endothelial cell adhesion molecule-1 (PECAM-1) but not of intercellular adhesion molecule-1 (ICAM-1), P-selectin or E-selectin. Both phenomena were attenuated by pretreatment with a tyrosine kinase inhibitor, especially a mitogen-activated protein kinase inhibitor, but not by inhibitors of other second messengers. In addition, a mitogen-activated protein kinase activator, anisomycin, by itself enhanced both neutrophil transendothelial migration and PECAM-1 expression within 3 h in a dose-dependent manner. Pretreatment with nitric oxide synthase inhibitors had no effect on these events. CONCLUSION/INTERPRETATION: These results suggest that hyperinsulinaemia could accelerate atherosclerosis by directly enhancing neutrophil transendothelial migration through increasing endothelial PECAM-1 expression via mitogen-activated protein kinase activation.

Cells, Cultured↗

High insulin exacerbates neutrophil-endothelial cell adhesion through endothelial surface expression of intercellular adhesion molecule-1 via activation of protein kinase C and mitogen-activated protein kinase.

AIMS/HYPOTHESIS: The association of insulin resistance and compensatory hyperinsulinaemia with increased coronary events in diabetic patients is poorly understood. There are few publications about the direct atherogenic actions of insulin on the endothelium compared with those on vascular smooth muscle cells. The aim of this study was to elucidate whether high insulin directly affects neutrophil-endothelial cell adhesion and surface expression of endothelial adhesion molecules. We also examined what intracellular mechanisms are involved in these events. METHODS: Studies of adhesion between neutrophils from healthy volunteers and human umbilical vein endothelial cells incubated in insulin-rich medium were carried out. Adhered neutrophils were quantified by measuring their myeloperoxidase activities and surface expression of endothelial adhesion molecules was examined using an enzyme immunoassay. RESULTS: High insulin enhanced neutrophil-endothelial cell adhesion with an increase in the expression of intercellular adhesion molecule-1 but not E-selectin or P-selectin. Both phenomena were attenuated by pretreatment with protein kinase C inhibitors and a mitogen activated protein kinase inhibitor. CONCLUSIONS/INTERPRETATION: These results suggest that hyperinsulinaemia causes vascular injury by directly exacerbating neutrophil-endothelial cell adhesion through increasing endothelial expression of intercellular adhesion molecule-1 via activation of protein kinase and mitogen activated protein kinase pathways.

Cell Adhesion↗

Effect of dietary sulfur amino acids on the taurine content of rat tissues.

The effect of dietary sulfur amino acids on the taurine content of rat blood and tissues was investigated. Three types of diet were prepared for this study: a low-taurine diet (LTD), normal taurine diet (NTD; LTD + 0.5% Met), and high-taurine diet (HTD; LTD + 0.5% Met + 3% taurine). These diets had no differing effect on the growth of the rats. The concentration of taurine in the blood from the HTD- and NTD-fed rats was respectively 1200% and 200% more than that from LTD-. In such rat tissues as the liver, the taurine content was significantly affected by dietary sulfur amino acids, resulting in a higher content with HTD and lower content with LTD. However, little or no effect on taurine content was apparent in the heart or eye. The activity for taurine uptake by the small intestine was not affected by dietary sulfur amino acids. The expression level of taurine transporter mRNA was altered only in the kidney under these dietary conditions: a higher expression level with LTD and lower expression level with HTD.

Animals↗

Sulfation of bisphenol A abolished its estrogenicity based on proliferation and gene expression in human breast cancer MCF-7 cells.

Bisphenol A, an endocrine-disrupting chemical, is widely used in many consumer products. We previously showed the sulfoconjugation of bisphenol A catalyzed by a human thermostable phenol sulfotransferase, ST1A3. The estrogenic potency of bisphenol A sulfate was compared with that of bisphenol A by an E-screen assay using human breast cancer MCF-7 cells. An increase in the expression level of an estrogen-responsive pS2 gene was also examined using MCF-7 cells after exposure to bisphenol A and its sulfate for their estrogenicity. Bisphenol A sulfate did not exhibit estrogenic effects at 0.1 microM (E-screen assay) and 1 mM (pS2 gene expression) compared with bisphenol A, which exhibited the effects at 3 nM (E-screen assay) and 1 microM (pS2 gene expression), respectively. We have therefore evaluated major roles of cytosolic phenol sulfotransferase in the human liver. Bisphenol A sulfation in human liver cytosols was inhibited by more than 90% by p-nitrophenol and quercetin, a typical substrate and specific inhibitor of phenol sulfotransferase, respectively. These results indicated that the estrogenicity of bisphenol A was abolished through its sulfation catalyzed by a human hepatic thermostable phenol sulfotransferase.

Arylsulfotransferase↗