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T Ishii

Publications and source records attributed to T Ishii.

At least 37 records · Page 2Linked to original sources
PubMed2005

Evidence for muon neutrino oscillation in an accelerator-based experiment.

We present results for nu(mu) oscillation in the KEK to Kamioka (K2K) long-baseline neutrino oscillation experiment. K2K uses an accelerator-produced nu(mu) beam with a mean energy of 1.3 GeV directed at the Super-Kamiokande detector. We observed the energy-dependent disappearance of nu(mu), which we presume have oscillated to nu(tau). The probability that we would observe these results if there is no neutrino oscillation is 0.0050% (4.0 sigma).

Journal Article↗
PubMed2005

Two cases of complete polymetatarsia without polydactyly.

We report two patients exhibiting complete polymetatarsia between the fourth and fifth metatarsals of the right foot, without supernumerary digit. To our knowledge, only a few cases of polymetatarsia without supernumerary digit have been reported, and all of those cases have involved incomplete duplication. Although there were no externally visible deformities in the present cases, plain radiographs revealed an extra bone between the fourth and fifth metatarsals. Case 1 presented with pain between the fourth and fifth metatarsals, and this pain ceased after resection of the extra metatarsal. Although case 2 was asymptomatic, the extra metatarsal of the left foot was resected during surgery for postaxial polydactyly of the right foot. Although differential diagnosis with os intermetatarseum was problematic, we concluded that the extra bones in the present cases were duplicated metatarsals, rather than accessory bones, based on three clinical findings: configuration of the extra metatarsal (articular cartilage and growth plate), in case 1; location of extra metatarsal (the most common site of polydactyly of the foot), in both cases; and polydactyly of the opposite foot, in case 2.

Child↗
PubMed2005

Living-related small bowel transplantation: two cases experiences.

We have recently performed living-related small bowel transplantation for 2 patients. The first patient was a 14-year-old boy with total parenteral nutrition (TPN)-dependent short-bowel syndrome associated with hypoganglionosis of the entire intestine. He received a bowel graft from his 43-year-old mother. The second patient was a 27-year-old woman, who had massive enterectomy due to volvulus and developed vitamin deficiencies and severe metabolic disorders as a result of long-term TPN. She underwent living-related bowel transplantation from her 57-year-old mother. Blood types were ABO identical, cytotoxic cross matches were negative, and cytomegalovirus statuses were positive-to-positive in both cases. Up to one third of the donor bowel was harvested from the donor distal ileum more than 30 cm away from the ileocecal valve. The graft vessels were connected to infrarenal aorta, and inferior vena cava. The immunosuppressive regimen consisted of daclizumab, tacrolimus, and steroid. The graft surveillance was accomplished using zoom endoscopy and mucosal biopsy. The first patient developed progressive acute cellular rejection (ACR) on the 9th postoperative day (POD)-9 requiring OKT-3 therapy, which was effective. Two months after transplantation, he was weaned from TPN, tolerating oral intake with a fully functioning graft. The second patient experienced no episode of ACR and was weaned off TPN on POD-29 with a functioning graft. Her metabolic disorder dramatically improved after bowel transplantation. Both donors had no complication and were discharged from the hospital on POD-10. Living-related bowel transplantation is an extreme option of treatment for patients with short-bowel syndrome.

Adolescent↗
PubMed2005

Expression of a candidate marker for progenitor cells, Musashi-1, in the proliferative regions of human antrum and its decreased expression in intestinal metaplasia.

AIM: Reliable makers for progenitor cells in the human stomach have not been elucidated. The aim of the present study was to clarify whether Musashi-1 (Msi-1), which has recently been proposed as a stem cell marker in mouse intestine, serves as a marker for progenitor cells in human stomach. METHODS AND RESULTS: Immunohistochemistry revealed that Msi-1+ cells were detected especially in the isthmus/neck region (the putative position of stem cells) of the adult antrum, but were limited to the basal regions of fetal pyloric glands during the early stages of development. These results suggest that Msi-1 expression occurs specifically in the stem cell-containing regions. Msi-1+ cells were intermingled with proliferating cell nuclear antigen (PCNA)+ cells in the isthmus/neck region of the adult antrum, but did not coexpress PCNA or Ki 67. Msi-1 expression overlapped partly with expression of MUC 5 AC and MUC 6, indicating that Msi-1+ cells retain some features of both foveolar and pyloric gland cell differentiation phenotypes. In contrast, Msi-1 expression in gastric glands showing intestinal metaplasia (IM) became weaker than that in the glands without IM. CONCLUSION: The specific expression of Msi-1 within the proliferative regions suggests that Msi-1 is a marker of cells with progenitor characteristics before active proliferation in human antrum.

Adult↗
PubMed2005

Expression of type V secretory phospholipase A in myocardial remodelling after infarction.

AIMS: Secretory phospholipase A2 is associated with ischaemic injury in the human heart, but the distribution of type V secretory phospholipase A2 (sPLA2-V) remains unknown. The significance of sPLA2-V in myocardial infarction was investigated histopathologically. METHODS: Sequential changes in the localization of sPLA2-V and its mRNA in myocardial tissues obtained from 30 autopsied hearts were examined by immunohistochemistry and in situ hybridization and compared with those of fibronectin, vascular endothelial growth factor (VEGF), interleukin (IL)-1beta, tumour necrosis factor (TNF)-alpha, and cyclooxygenase-2 (COX-2). RESULTS: No expression of sPLA2-V was observed in normal heart, but it was promptly expressed in wavy myofibres positive for fibronectin just after the onset of infarction. sPLA2-V was subsequently expressed in ischaemic cardiomyocytes around the lesion. The expression decreased at the granulation tissue and disappeared at the chronic stage with scar formation. The distribution of the signal for sPLA2-V mRNA paralleled that of the protein. Ischaemic myocytes around the lesion expressed VEGF, IL-1beta, TNF-alpha and COX-2 at all stages. CONCLUSIONS: sPLA2-V production in myocardium is limited to the acute phase of infarction. sPLA2-V may play a dual role, acting both to remove degraded cell-membrane through cooperative activity with COX-2 in necrotic areas and to attack ischaemic myocytes around the lesion via degradation of membrane phospholipids.

Adult↗
PubMed2005

Clearance rates of cerivastatin metabolites in a patient with cerivastatin-induced rhabdomyolysis.

We report on a patient who developed acute rhabdomyolysis after taking cerivastatin. A 74-year-old hypercholestrerolaemic woman taking cerivastatin (0.15 mg/day) for 22 days complained of general muscle weakness and muscle pain. Her serum creatinine phosphokinase level was 19,190 IU/L. Serum myoglobin was over 3000 ng/mL. Serum concentration of cerivastatin at 6 h after taking the last dose (0.15 mg) was 8062.5 ng/L, which was almost 5.7 times higher than that of normal persons. The serum concentration of cerivastatin showed that the half-life of cerivastatin in this patient was 22.4 h, compared with 2.4 h for normal controls. Cerivastatin is catabolized by cytochrome P450, 3A4 and 2C8 to M-1, and by 2C8 to M-23. The ratio of M-23 to M-1 in her serum was much lower than that of control persons (0.64 vs. 2.08). She had previously taken simvastatin which is metabolized by CYP3A4, without any sign and symptoms of rhabdomyolysis. These results suggest that the slowed clearance of cerivastatin in this patient might have been compounded by cytochrome P450, 2C8 dysfunction.

Acute Disease↗
PubMed2005

Coronary arterial calcification is associated with albuminuria in type 2 diabetic patient.

AIM: Although microalbuminuria has been suggested as an independent risk factor for ischemic heart disease, the relationship between diabetic nephropathy and macroangiopathy remains unclear. Previously, we reported that coronary artery calcification detected by electron beam computed tomography (EBCT) could indicate the degree of coronary atherosclerosis in type 2 diabetic patients. In this study, we examine the association between coronary arterial calcification and microalbuminuria and aortic calcification and microalbuminuria. METHODS: Two hundred and fifty-six patients, including 177 type 2 diabetic patients (106 patients with normoalbuminuria, 71 with microalbuminuria) and 79 non-diabetic patients were evaluated by assessing the urinary albumin excretion rate and using EBCT to determine a coronary calcification score (CCS) and an aortic calcification score (ACS). RESULTS: No differences were observed regarding age, smoking index or BMI. Diabetic patients exhibited a greater CCS than non-diabetic subjects (non-diabetes 33 +/- 75 vs. diabetes 203 +/- 467, p < 0.05). Diabetic patients with microalbuminuria exhibited the most advanced CCS (253 +/- 491, p < 0.05). In contrast, no difference was observed in ACS among three groups. Multiple regression analysis showed that CCS is significantly associated with urinary albumin excretion rate as well as age, duration of diabetes and serum creatinine (R(2) = 0.31), while ACS is strongly associated with age, smoking, serum creatinine, systolic blood pressure and low-density lipoprotein cholesterol level (R(2) = 0.29). CONCLUSION: Increased urinary albumin excretion is associated with coronary arterial calcification in diabetic patients.

Age Factors↗
PubMed2005

Repair of large full-thickness articular cartilage defects in the rabbit: the effects of joint distraction and autologous bone-marrow-derived mesenchymal cell transplantation.

We produced large full-thickness articular cartilage defects in 33 rabbits in order to evaluate the effect of joint distraction and autologous culture-expanded bone-marrow-derived mesenchymal cell transplantation (ACBMT) at 12 weeks. After fixing the knee on a hinged external fixator, we resected the entire surface of the tibial plateau. We studied three groups: 1) with and without joint distraction; 2) with joint distraction and collagen gel, and 3) with joint distraction and ACBMT and collagen gel. The histological scores were significantly higher in the groups with ACBMT collagen gel (p < 0.05). The area of regenerated soft tissue was smaller in the group allowed to bear weight (p < 0.05). These findings suggest that the repair of large defects of cartilage can be enhanced by joint distraction, collagen gel and ACBMT.

Animals↗
PubMed2004

Genomic paleontology provides evidence for two distinct origins of Asian rice (Oryza sativa L.).

The origin of rice domestication has been the subject of debate for several decades. We have compared the transpositional history of 110 LTR retrotransposons in the genomes of two rice varieties, Nipponbare (Japonica type) and 93-11 (Indica type) whose complete sequences have recently been released. Using a genomic paleontology approach, we estimate that these two genomes diverged from one another at least 200,000 years ago, i.e., at a time which is clearly older than the date of domestication of the crop (10,000 years ago, during the late Neolithic). In addition, we complement and confirm this first in silico analysis with a survey of insertion polymorphisms in a wide range of traditional rice varieties of both Indica and Japonica types. These experimental data provide additional evidence for the proposal that Indica and Japonica rice arose from two independent domestication events in Asia.

Base Sequence↗
PubMed2004

Nucleotide polymorphism in the Adh1 locus region of the wild rice Oryza rufipogon.

Nucleotide variation in the alcohol dehydrogenase (Adh1) locus region of the wild rice Oryza rufipogon and its related species was analysed to clarify the maintenance mechanism of DNA variation in Oryza species. The estimated nucleotide diversity in the Adh1 locus region of O. rufipogon was 0.002, which was one of the lowest values detected in nuclear loci of plant species investigated so far. Tests of neutrality detected significantly negative deviation from the neutral mutation model for the coding region, especially for replacement sites. When each of the ADH1 domains was considered, significance was detected only for the catalytic domain 1. These results suggest purifying selection in the Adh1 coding region. In the phylogenetic tree of Oryza species based on Adh1 variation, cultivated rice O. sativa subspp. japonica and indica were included in the cluster of O. rufipogon. The genetic distance of the Adh1 region between O. rufipogon and O. sativa was as low as the nucleotide diversity of O. rufipogon. These results imply that O. rufipogon and O. sativa cannot be classified based on the nucleotide variation of Adh1. No replacement divergence between O. rufipogon and the other three A-genome species (O. glumaepatula, O. barthii and O. meridionalis) were detected, indicating that ADH1 is conserved in the A-genome species. On the other hand, between O. rufipogon and the E-genome species O. australiensis, replacement changes were detected only in the catalytic domain 1. The difference in replacement substitutions between the A- and E-genome species may be related to adaptive changes in the ADH1 domains, reflecting environmental differences where the species encounter anaerobic stress.

Alcohol Dehydrogenase↗
PubMed2004

Genetic diversity and phylogeny of Japanese sake-brewing rice as revealed by AFLP and nuclear and chloroplast SSR markers.

Japanese rice ( Oryza sativa L.) cultivars that are strictly used for the brewing of sake (Japanese rice wine) represent a unique and traditional group. These cultivars are characterized by common traits such as large grain size with low protein content and a large, central white-core structure. To understand the genetic diversity and phylogenetic characteristics of sake-brewing rice, we performed amplified fragment length polymorphism and simple sequence repeat analyses, using 95 cultivars of local and modern sake-brewing rice together with 76 cultivars of local and modern cooking rice. Our analysis of both nuclear and chloroplast genome polymorphisms showed that the genetic diversity in sake-brewing rice cultivars was much smaller than the diversity found in cooking rice cultivars. Interestingly, the genetic diversity within the modern sake-brewing cultivars was about twofold higher than the diversity within the local sake-brewing cultivars, which was in contrast to the cooking cultivars. This is most likely due to introgression of the modern cooking cultivars into the modern sake-brewing cultivars through breeding practices. Cluster analysis and chloroplast haplotype analysis suggested that the local sake-brewing cultivars originated monophyletically in the western regions of Japan. Analysis of variance tests showed that several markers were significantly associated with sake-brewing traits, particularly with the large white-core structure.

Analysis of Variance↗
PubMed2004

Evidence for an oscillatory signature in atmospheric neutrino oscillations.

Muon neutrino disappearance probability as a function of neutrino flight length L over neutrino energy E was studied. A dip in the L/E distribution was observed in the data, as predicted from the sinusoidal flavor transition probability of neutrino oscillation. The observed L/E distribution constrained nu(micro)<-->nu(tau) neutrino oscillation parameters; 1.9x10(-3) 0.90 at 90% confidence level.

Journal Article↗
PubMed2004

Search for electron neutrino appearance in a 250 km long-baseline experiment.

We present a search for electron neutrino appearance from accelerator-produced muon neutrinos in the K2K long-baseline neutrino experiment. One candidate event is found in the data corresponding to an exposure of 4.8 x 10(19) protons on target. The expected background in the absence of neutrino oscillations is estimated to be 2.4+/-0.6 events and is dominated by misidentification of events from neutral current pi(0) production. We exclude the nu(micro) to nu(e) oscillations at 90% C.L. for the effective mixing angle in the 2-flavor approximation of sin((2)2theta(microe)( approximately 1/2sin((2)2theta(13))>0.15 at Deltam(2)(microe)=2.8 x 10(-3) eV(2), the best-fit value of the nu(micro) disappearance analysis in K2K. The most stringent limit of sin((2)2theta(microe)<0.09 is obtained at Deltam(2)(microe)=6 x 10(-3) eV(2).

Journal Article↗
PubMed2004

Limits on the neutrino magnetic moment using 1496 days of Super-Kamiokande-I solar neutrino data.

A search for a nonzero neutrino magnetic moment has been conducted using 1496 live days of solar neutrino data from Super-Kamiokande-I. Specifically, we searched for distortions to the energy spectrum of recoil electrons arising from magnetic scattering due to a nonzero neutrino magnetic moment. In the absence of a clear signal, we found micro(nu)</=(3.6x10(-10))micro(B) at 90% C.L. by fitting to the Super-Kamiokande day-night spectra. The fitting took into account the effect of neutrino oscillation on the shapes of energy spectra. With additional information from other solar neutrino and KamLAND experiments constraining the oscillation region, a limit of micro(nu)</=(1.1x10(-10))micro(B) at 90% C.L. was obtained.

Journal Article↗
PubMed2004

The expression of intestinal CYP3A4 in the piglet model.

PURPOSE: In our previous study, the blood levels of tacrolimus were higher in the short bowel and small bowel transplantation models than those in controls. Metabolism by intestinal cytochrome p450 3A4 (CYP3A4) has been reported to influence the blood level of orally administered tacrolimus. We performed immunohistochemistry to examine the localization of intestinal CYP3A4. MATERIALS AND METHODS: Twenty-four piglets were divided into three groups: group 1 were controls (n = 11); group 2, ileal resection of 2/3 proximal small intestine (n = 5); and group 3, total small intestinal resection followed by 1/3 allotransplantation of ileum (n = 8). Tacrolimus was orally administered from postoperative days 3 to 7. On day 7, blood samplings were performed for the trough level and the calculation of area under the concentration time curve (AUC). Intestinal specimens from the jejunum, ileum, colon, and ileal graft were obtained on days 0 and 10 for immunohistochemistry of CYP3A4. RESULTS: The trough and AUC values in group 2 were significantly higher than those in group 1. Furthermore those measurements in group 3 animals were higher than in group 2 (trough levels: 2.5 +/- 1.7, 11.2 +/- 2.1, 16.3 +/- 2.7 ng/mL and AUC values: 126 +/- 90, 319 +/- 155, 546 +/- 117 ng. h/mL). The expression levels of CYP3A4 were, jejunum > ileum > ileal graft > colon. CONCLUSIONS: The intensity and extent of CYP3A4 staining diminished in the ileal graft showing an inverse correlation to the blood concentrations.

Animals↗
PubMed2004

The colon displays an absorptive capacity of tacrolimus.

PURPOSE: In our previous study, blood levels of orally administered tacrolimus were significantly higher in short bowel piglets than in control animals. It has been reported that the blood levels of tacrolimus are influenced by the metabolic activity of intestinal CYP3A4. If tacrolimus may be absorbed in the colon, direct administration of drug into this organ might be useful to augment bioavailability since the expression of CYP3A4 is low at this site. In the present study we evaluated the absorptive capacity of tacrolimus in the colon. MATERIALS AND METHODS: Piglets were divided into four groups: groups 1 and 2 were controls (n = 11 and 3, respectively); group 3 underwent resection of the entire small intestine (n = 8); and group 4 had a catheter placed in the cecum (n = 4). In groups 1 and 3, tacrolimus was administered orally; in group 2 it was given intravenously; and in group 4 it was injected into cecum through the catheter from postoperative days 3 to 7. On day 7, blood samples were obtained for drug measurements to calculate the area under the concentration time curve (AUC) values. RESULTS: The trough level and AUC values of tacrolimus in group 4 as well as in group 3 were significantly higher than those in group 1. In Group 4 animals showed a 60-minute time to peak concentration. CONCLUSIONS: Tacrolimus is absorbed by the colon. Since the blood levels were not influenced by the metabolic activity in the graft bowel, direct administration of tacrolimus into the colon might be useful in small intestinal transplantation.

Animals↗
PubMed2004

Expression of cholesteryl ester transfer protein (CETP) in germinal centre B cells and their neoplastic counterparts.

AIMS: Cholesteryl ester transfer protein (CETP) is known to facilitate the transfer of lipids between plasma lipoproteins. Previous studies on human tissues have determined that the spleen contains large amounts of CETP mRNA, while the exact location of CETP in such organs remains unknown. In the present study, our aim was to locate CETP protein expression at the cellular level in human normal and neoplastic lymphoid organs. METHODS AND RESULTS: In-situ hybridization (ISH) and immunohistochemistry were applied to pathology specimens. A specific rabbit anti-CETP antibody was used for immunohistochemical analysis, together with another CETP-specific monoclonal antibody. A riboprobe for ISH was derived from CETP cDNA. Immunohistochemically, CETP was localized in germinal centre B cells and a proportion of marginal zone B cells. ISH showed that CETP mRNA was located mostly in the same areas. When 141 malignant lymphomas of various subtypes were studied, high expression of CETP, equivalent to that found in normal germinal centre B cells, was demonstrated in lymphoma subtypes that are currently regarded as the neoplastic counterparts of primarily germinal centre B cells. CONCLUSION: CETP localizes B cells in germinal centres, a proportion of post-germinal centre B cells and their neoplastic counterparts.

Animals↗