Biomedical subjects

Y Matsui

Publications and source records attributed to Y Matsui.

At least 19 recordsLinked to original sources

PubMed2007

Epigenetic regulation for the induction of meiosis.

The germ cell lineage is the sole cell lineage through which genomic information is transmitted into successive generations. To this end, germ cells undergo various specific differentiation steps including meiosis, whose regulation seems to correlate closely with fundamental mechanisms that create differences between germ cells and somatic cells. In mammals, meiosis is triggered by extra-embryonic stimuli such as retinoic acid, which may induce various intracellular molecular cascades promoting meiosis. In addition, the specific epigenetic status arranged in germ cells before and after induction of meiosis, including meiosis-specific transcription control based on histone methylation by a novel histone methyltransferase Meisetz, is also critical for its proper progression.

Animals↗

PubMed2006

Can you diagnose for vertebral fracture correctly by plain X-ray?

INTRODUCTION: A wrong diagnosis of latent vertebral fracture is often made when it is based on plain X-ray imaging. Magnetic resonance imaging (MRI) has a high degree of accuracy for the definite diagnosis. This study was designed to identify ways to support improvements in the diagnostic accuracy of plain X-ray (X-P). METHODS: We studied X-P and MRI images of 120 women and men (age range: 50-96 years). Five orthopedists and two radiologists interpreted front and lateral thoracolumbar X-Ps and MRI images. The correct diagnosis rate for the presence and location of incident vertebral fractures and the correct diagnosis rate according to morphological classifications were analyzed. RESULTS: A correct diagnosis of incident fractures was made in 51.5% of cases overall. Diagnoses of non-incident fracture based on X-P in those cases with incident fracture based on MRI (false positive) occurred in 24.8% of the patients, while diagnoses of incident fracture based on X-P in those cases without incident fracture based on MRI (false negative) occurred in 6.5% of the patients. The application of morphological classifications (the primary osteoporosis diagnostic criteria and Yoshida's classification) resulted in the correct diagnosis rate being significantly higher in the group without prevalent fracture even when there were morphological changes (wedge, indented, protruding type) in the anterior bone cortex. Odds ratios were investigated for factors that would affect the correct diagnosis rate, including age, body weight, lumbar vertebrae bone mineral density, and examiner ability. In an overall investigation, age (OR=0.660), body weight (OR=2.082), and examiner ability (p=0.0205) affected the correct diagnosis rate. CONCLUSION: The correct diagnosis rate for incident vertebral fractures with X-Ps was low (24.8%) and in cases with prevalent fractures, the rate was even lower (16.8%), but the number of prevalent fractures and BMD did not exert an effect. One key improving the correct diagnosis rate may be to pay attention to morphological changes in the anterior bone cortex.

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PubMed2006

Dicoumarol potentiates cisplatin-induced apoptosis mediated by c-Jun N-terminal kinase in p53 wild-type urogenital cancer cell lines.

3-3'-Methylene-bis [4-hydroxycoumarin] (dicoumarol), an inhibitor of NADPH:quinone oxidoreductase 1, has been reported to possess potential antineoplastic effects and the ability to abrogate p53 protein. In the present study, we investigated the cytotoxic effects of dicoumarol in combination with cisplatin (CDDP), using four bladder (RT112, 253J, J82 and UMUC3) and two prostate (LNCap and PC3) cancer cell lines. Single treatment with 100 microM dicoumarol suppressed cell proliferation but did not induce apoptosis at 24 h in all cell lines examined. On the other hand, pretreatment with dicoumarol enhanced cytotoxicity of CDDP in three cell lines with wild type of p53 (RT112, 253J and LNCap), but not in three other cell lines with mutant p53 or in RT112 stable transfectants with a dominant-negative mutant of p53. In RT112 and LNCap, CDDP induced p53 and p21 expression, while pretreatment of dicoumarol suppressed induction of p53/p21 and resulted in sequential activation of c-Jun N-terminal kinase (JNK) in a time-dependent manner. Furthermore, inhibition of JNK, using SP600125, completely suppressed activity of caspases and poly-(ADP-ribose) polymerase cleavage, leading to suppression of enhancement of CDDP-mediated apoptosis by dicoumarol. These results suggested that dicoumarol could enhance cytotoxicity of CDDP in urogenital cancer cells with wild-type p53 through the p53/p21/JNK pathways.

Antineoplastic Agents↗

PubMed2006

The alpha2 type IX collagen tryptophan polymorphism is associated with the severity of disc degeneration in younger patients with herniated nucleus pulposus of the lumbar spine.

Tryptophan alleles in COL9A2 (Trp2) and COL9A3 (Trp3) have been linked to lumbar disc diseases in the Finnish population. Although such diseases consist of various pathogenetically different conditions, detailed analysis of each has not been well documented. The aim of this study was to clarify whether the collagen IX tryptophan alleles influence the symptomatic degeneration of the lumbar disc in Japanese patients with herniated nucleus pulposus. We performed a prospective study of 84 patients who underwent lumbar discectomy. The degree of disc degeneration was evaluated by magnetic resonance images in relation to the collagen IX genotype. Twenty patients (21.4%) had the Trp2 allele and no patients had the Trp3 allele. Patients under 40 years with the Trp2 allele showed more severe disc degeneration at the surgical level than did those without the Trp2 allele (odds ratio 6.00, P=0.043). In contrast, patients aged 40 years or over did not show significant association between disc degeneration and collagen IX genotype. Our results suggest that the Trp2 allele is an age-dependent risk factor for the severity of disc degeneration in younger patients with symptomatic herniated nucleus pulposus of the lumbar spine.

Adult↗

PubMed2006

Hemophagocytic syndrome after adult-to-adult living donor liver transplantation.

Hemophagocytic syndrome is a fatal complication after liver transplantation that is rarely reported. Among 260 adult patients who underwent living donor liver transplantation at our hospital, three cases (1%) were complicated with hemophagocytic syndrome. Intensive investigation revealed Aspergillus, cytomegalovirus, and hepatitis C virus as the most likely causative organisms in each patient. Despite the immediate initiation of anti-infectious treatment and supportive care, all patients died. When pancytopenia with possible underlying infectious disease is observed in liver transplant recipients, hemophagocytic syndrome should be suspected and bone marrow biopsy considered. The prognosis of hemophagocytic syndrome remains poor and further investigations are required to establish effective therapeutic options.

Adult↗

PubMed2006

Preoperative estimation of right lateral sector graft by three-dimensional computed tomography.

The right lateral sector is an alternative graft for living donor liver transplantation. Three-dimensional image reconstruction of right lateral sector grafts was performed to reveal vascular anatomy and volume using three-dimensional computed tomography software in three donors. There was a correlation between actual and estimated volume (r=.93), although actual graft volume tended to be larger than the preoperative estimated volume. In one donor, a portal branch of the right lateral sector was independently ramified. The branch was sacrificed in the operation because its territory volume was only 44 cm3. Three-dimensional images matched the shape of the right lateral sector graft. Three-dimensional computed tomography might be useful before donor hepatectomy, providing important information for decisions regarding the operative procedure.

Humans↗

PubMed2006

New-onset diabetes mellitus after living donor liver transplantation: possible association with hepatitis C.

BACKGROUND: The relationship between hepatitis C virus (HCV) infection and new-onset diabetes mellitus (NODM) after liver transplantation is a controversial issue. METHODS: A total of 223 adult living donor liver transplantation (LDLT) recipients followed for more than 6 months were analyzed for the prevalence of NODM. The prevalence was compared between 62 HCV-positive and 161 HCV-negative patients. All the HCV-positive patients underwent preemptive antiviral treatment with interferon alpha2b and ribavirin. RESULTS: Preoperative diabetes mellitus was more frequently observed in HCV-positive patients (18% vs 4%, P = .001). NODM occurred more frequently in HCV-positive patients (41% vs 22%, P = .003). Multivariate analysis, however, revealed that HCV was not a predictor for NODM. A comparison of 14 HCV-positive patients with persistent NODM and 48 patients without persistent NODM indicated that there was no significant difference in the frequency of the viral response to antiviral therapy nor in HCV-RNA levels. Impaired glucose tolerance did not impact postoperative survival after LDLT. CONCLUSIONS: HCV was not associated with the prevalence of NODM after LDLT. NODM did not influence patient survival.

Adult↗

PubMed2006

Activation of c-Jun N-terminal kinase (JNK) signalling in experimentally induced gastric lesions in rats.

The c-Jun N-terminal kinase (JNK) participates in intracellular signalling cascades that mediate inflammatory responses. Therefore, the JNK signalling may be involved in gastric injury and inhibition of this pathway may form the basis of a new strategy for the treatment of gastric injury. The aim of this study was to determine whether JNK participates in the formation of gastric lesions in an experimental model. Acute gastric injury was induced in Sprague-Dawley rats by intragastric administration of 100% ethanol. The amount of phospho-JNK in the rat stomach was determined using immunohistochemistry and Western analysis. Animals received subcutaneous injections of a specific JNK inhibitor SP600125 or vehicle and the extent of mucosal damage in the stomach was determined. Western analysis revealed early phosphorylation of JNK and, to a lesser extent, p38 as well as late phosphorylation of the p42/44 extracellular signal-related kinases during the development of gastric lesions. JNK was phosphorylated in epithelial cells and in occasional mononuclear cells present at lesion sites. These cells were rarely found in samples from control specimens. Treatment with SP600125 significantly reduced the extent of gastric lesions. These findings indicate that experimental gastric injury is associated with activation of the JNK signalling pathway, and also suggest that JNK inhibitors may play a role in the treatment of gastric injury in humans.

Animals↗

PubMed2006

Intrapatellar tendon lipoma with chondro-osseous differentiation: detection of HMGA2-LPP fusion gene transcript.

A 54 year old man developed an unusual lipoma in the patellar tendon, consisting of a fibro-adipose component and a chondro-osseous component. The fibro-adipose component contained mature adipocytes, lipoblasts, and fibroblasts; the chondro-osseous component showed typical endochondral bone formation. Molecular analysis showed that the identical HMGA2-LPP fusion transcript-characteristic of lipoma, parosteal lipoma, and pulmonary chondroid hamartoma-was detectable in the both components.

Adipogenesis↗

PubMed2006

Analysing mass balance of viruses in a coagulation-ceramic microfiltration hybrid system by a combination of the polymerase chain reaction (PCR) method and the plaque forming units (PFU) method.

Virus removal experiments using river water spiked with bacteriophages were conducted by an in-line coagulation-ceramic microfiltration hybrid system to investigate the effects of filtration flux (62.5 and 125 L/(m2 x h)) and type of virus (Qbeta and MS2) on virus removal. In addition, the mass balance of viruses through the hybrid system was analysed by quantifying the infectious and inactive viruses by a combination of the polymerase chain reaction (PCR) method and the plaque forming units (PFU) method. Even when the system was operated at high filtration flux (125 L/(m2 x h)), high virus removal (> 6 log) with short coagulation time (2.4 s) was successfully achieved by dosing polyaluminium chloride (PACI) at more than 1.08 mg-Al/L. Removal performances were different between Qbeta and MS2, although their diameters are almost the same: greater virus removal was achieved for MS2 at PACI dosing of 0.54 mg-Al/L, and for Qbeta at PACI dosing of more than 1.08 mg-Al/L. The combination of the PCR and PFU methods revealed that two phenomena, adsorption to/entrapment in aluminium floc and virucidal activity of PACI, partially account for the high virus removal in the coagulation-MF hybrid system.

Bacteriophages↗

PubMed2006

Screening level analysis for monitoring pesticide in river water using a hydrological diffuse pollution model with limited input data.

To predict rice-farming pesticide concentrations in river water with imprecise model inputs for screening-level analysis, a basin-scale runoff model was developed. The Monte Carlo method was applied to create estimates of input data regarding agricultural work schedules and parameters for pesticide decomposition and sorption in solids and water. The prediction accuracy of the model was evaluated when used with non-optimised pesticide parameters; the model was calibrated using hydrological data alone without reference to observed pesticide concentration data. Overall, predictions for the pesticide concentrations were successful within order-of-magnitude accuracy. The pesticide rankings according to the predicted concentration roughly agreed with those observed. The success of screening-level analysis indicates that the model prediction can help in selection of pesticides to be monitored and in determining the monitoring schedule for the river basin.

Agriculture↗

PubMed2006

[Reconstruction of neck vessels in endovascular repair of aortic arch aneurysms].

We report 6 cases of aortic arch aneurysms necessitating reconstruction of the neck vessel during stent-graft (SG) placement. All patients were male and their average age was 75 years. The proximal landing zone was zone 0 in 2, zone 1 in 2, and zone 2 in 2 patients. The left subclavian artery (LSCA) was revascularized in every case; using left common carotid artery (LCCA)-LSCA bypass in 3, axillo-axillary artery bypass in 2, and LSCA transposition in 1. Prophylactic LCCA revascularization was done in 2 in which obstruction of LCCA by SG was anticipated. The proximal portion of LSCA from the origin of the vertebral artery was ligated in 3, and divided in 1. Two types of SG were used; Z stent in 1 and Matsui-Kitamura stent in 5. There was no hospital death or perioperative stroke. In the patient with Z stent, SG could not be deployed because of kinking of the delivery system. This patient subsequently underwent surgical SG placement under hypothermic circulatory arrest. In the other 5, SG was deployed without any type of endoleak. Postoperative complication included incomplete phrenic nerve palsy in 1. Prophylactic bypass for LCCA was divided because SG did not obstruct the antegrade flow of LCCA. Revascularization of neck vessels can be performed with low morbidity in endovascular repair of aortic arch aneurysms.

Aged↗

PubMed2005

Observation of magnetic ripple and nanowidth domains in a layered ferromagnet.

We investigated ferromagnetic domain structures on nanometer to micrometer scale for single crystals of a layered ferromagnet, La(2-2x)Sr(1+2x)Mn2O7 (0.32 < or = x < or = 0.40), as functions of x and temperature by means of Lorentz electron microscopy. We have succeeded in observing the evolution of magnetic ripple structure, dynamically, related to a spin reorientation transition where the magnetization direction switches between parallel and perpendicular to the layers. Our high-resolution magnetic domain imaging revealed that the ripple state is characterized by the evolution of magnetic nanowidth domains.

Journal Article↗

PubMed2005

Liver metastasis and ICAM-1 mRNA expression in the liver after carbon dioxide pneumoperitoneum in a murine model.

BACKGROUND: Liver metastasis of colorectal malignancies is an important prognostic factor. Several studies have demonstrated that carbon dioxide (CO2) pneumoperitoneum enhances liver metastasis in animal models. Little is known about intercellular adhesion molecule-1 (ICAM-1) and tumor necrosis factor-alpha (TNF-(alpha) mRNA expression in the liver after CO2 pneumoperitoneum. METHODS: Forty-five male BALB/c mice were randomly divided into three groups after intra-splenic tumor cell (colon 26) inoculation and the following procedures were performed: CO2 pneumoperitoneum (n = 15), open laparotomy (n = 15), and anesthesia alone (n = 15). On day 7 after each procedure, the livers were excised and the number and diameter of the tumor nodules and the cancer index score were determined. Another 90 male BALB/c mice were randomly divided into three groups as described above, and they underwent each procedure (n = 30 each). After each procedure, the livers were excised on days 0, 1, 3, and ICAM-1 and TNF-alpha mRNA expression were examined by real-time RT-PCR using SYBR Green I. RESULTS: The number of tumor nodules and the cancer index score were larger in the CO2 pneumoperitoneum group than in the control group (p < 0.05). The mean diameter of the tumor nodules was not different among the three groups. The expression of ICAM-1 in the CO2 pneumoperitoneum group was higher than that in the other groups on day 1 (p < 0.05), and the TNF-alpha mRNA was higher than that in the control group on day 1 (p < 0.05). CONCLUSIONS: CO2 pneumoperitoneum enhances liver metastasis compared with anesthesia alone, and ICAM-1 expression in the liver after the pneumoperitoneum plays an important role in establishing liver metastasis in a murine model.

Animals↗

PubMed2005

Morphological changes in hepatic vascular endothelium after carbon dioxide pneumoperitoneum in a murine model.

BACKGROUND: Liver metastasis is an important prognostic factor in advanced colorectal cancer. Several studies have demonstrated that carbon dioxide (CO2) pneumoperitonem enhances liver metastasis in an animal model. In the present study, we used scanning electron microscopy (SEM) to investigate morphological changes in hepatic vascular endothelium after CO2 pneumoperitoneum in a murine model. METHODS: Thirty-three male BALB/c mice were randomized to undergo pneumoperitoneum (CO2, air, or helium), open laparotomy, and anesthesia alone. After each procedure, the animals' livers were excised at days 0, 1, and 3 and examined by SEM. RESULTS: In the CO2 pneumoperitoneum group, we observed rough surface and derangement of the hepatic vascular endothelial cells and intercellular clefts on day 1. In the other groups, no major morphologic changes were observed at any time. CONCLUSIONS: Hepatic vascular endothelium changes after CO2 pneumoperitoneum. Such characteristic changes may play an important role in establishing liver metastasis after CO2 pneumoperitoneum.

Acidosis↗

PubMed2005

Effect of 5-Campestenone (24-methylcholest-5-en-3-one) on Zucker diabetic fatty rats as a type 2 diabetes mellitus model.

We examined the therapeutic effects of dietary exposure to 5-campestenone (24-methylcholest-5-en-3-one), an enone derivative of campesterol, in Zucker diabetic fatty (ZDF) rats, an animal model of type 2 diabetes mellitus. Dietary 0.6 % exposure to 5-campestenone caused marked reduction in hemoglobin A1c (HbA1c), plasma total cholesterol, triglycerides and non esterified fatty acid (NEFA). In particular, plasma triglyceride levels were reduced in the 0.6 % 5-campestenone-fed group to about 25 % of that in the control group. In the oral glucose tolerance test (OGTT) at three and seven weeks after the beginning of treatment, 5-campestenone limited the rise of blood glucose levels by oral administration of glucose dose-dependently. Amounts of adipose tissue in the retroperitoneum and periepididymal area as well as abdominal subcutaneous fat were significantly decreased in animals fed 0.6 % 5-campestenone. The blood leptin concentration on the final day of feeding was significantly in animals administered 5-campestenone. No obvious anomaly due to consumption of 5-campestenone was detected in necropsy or clinical observations.

Administration, Oral↗

PubMed2005

Ferromagnetic microstructure in double exchange manganites.

Ferromagnetic (FM) microstructures in double-exchange manganites, La0.825Sr0.175MnO3, were examined by low-temperature Lorentz microscopy. It was found that the FM domains with the stripe pattern were in the FM metallic phase of La0.825Sr0.175MnO3. The FM insulator phase induced by the substitution of Al ions for Mn in La0.825Sr0.175MnO3 was characterized as a complex mixture of the characteristic FM domains, which consists of three types of FM domains: the stripe domains, the plate-shaped domains and the complicated wavy domains. It is suggested that this mixture of different types of FM domains breaks the coherence of the electric conductivity and gives rise to the insulating character in Al doped La0.825Sr0.175MnO3.

Journal Article↗

PubMed2005

[Overlapping ventriculoplasty for ischemic cardiomyopathy].

We have previously reported overlapping cardiac volume reduction operation (OLCVR) for dilated cardiomyopathy. Because of the acceptable clinical outcome and especially the excellent ellipsoidal shape of the left ventricle (LV) after surgery, we extended this indication for ischemic cardiomyopathy (ICM) with dilated LV. In such cases we combined OLCVR with mitral annuloplasty and papillary muscles approximation (PMA), called integrated overlapping ventriculoplasty (IOLVP). From March 2003 to July 2004, we performed IOLVP with coronary artery bypass grafting (CABG) for 8 patients who were diagnosed ICM. There is no operative mortality. Pre- and postoperative hemodynamics data are follows: LV ejection fraction (LVEF) improved from 22.4 +/- 11.9 to 33.4 +/- 10.5%, LV end-diastolic volume index (LVEDVI) decreased from 155.5 +/- 26.5 to 93.7 +/- 13.5 ml/m2 and LV end-diastolic diameter (LVDd) diminished from 66.0 +/- 8.9 to 60.5 +/- 8.4mm. Mitral regurgitation changed from 2.6 +/- 0.8 to 0.1 +/- 0.2 degree. New York Heart Association (NYHA) functional class improved from 3.3 +/- 0.5 to 1.3 +/- 0.5. LV shape became ellipsoidal without akinesis lesion. IOLVP is considered as a good option for ICM with dilated left ventricle.

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