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T Sato

Publications and source records attributed to T Sato.

At least 55 records · Page 3Linked to original sources
PubMed2006

[Small sclerosing hemangioma combined with primary lung cancer; report of a case].

A 56-year-old woman underwent a surgery for right breast cancer when she was 51-year-old. In February 2002, computed tomography (CT) was performed as a part of a follow-up study and showed 2 small nodules in the lower lobe of her right lung: one was 10 mm nodule in S9, and another was 5 mm in S6. On a follow-up CT in March 2005, the S9 nodule had enlarged to 19 mm and was looked as ground glass opacity (GGO). We thought it was primary lung cancer. In contrast, the nodule in S6 had not enlarged and it was thought to be benign. In May 2005, right lower lobectomy was performed. The S9 nodule was diagnosed as adenocarcinoma, and the S6 nodule as sclerosing hemangioma.

Adenocarcinoma↗
PubMed2005

Rapid disease progression correlates with instability of mutant SOD1 in familial ALS.

Studies on the clinical course of familial ALS suggest that the duration of illness is relatively consistent for each mutation but variable among the different mutations. The authors analyzed the relative amount of mutant compared with normal SOD1 protein in the erythrocytes from 29 patients with ALS with 22 different mutations. Turnover of mutant SOD1 correlated with a shorter disease survival time.

Adult↗
PubMed2005

Sorption and displacement of pyrene in soils and sediments.

Sorption isotherms of pyrene on soils and sediments were examined to understand its sorption behavior. All systems examined exhibited nonlinear sorption. Sorption nonlinearity was found to be a function of the polarity index of soil/sediment organic matter (SOM), suggesting that the degree of condensation of SOM, characterized by its polarity index, was correlated with the sorption behavior of pyrene. The polarity index of SOM could be a new factor for explaining the sorption nonlinearity. The sorption affinity of two soils and two sediments for pyrene increased with decreasing SOM polarity. A higher sorption affinity in the two soils was associated with a higher degree of condensation of SOM compared to that of the two sediments. A displacement test was performed after pyrene sorption using phenanthrene as a displacer. Pyrene was displaced in all systems examined, and nonlinearity became less pronounced after displacement. Such an increase in isotherm linearity implied that sorption site energies became more homogeneous after displacement. Furthermore, the site energy distribution IE*) derived from the Freundlich model parameters showed that energy reduction of high-energy sites was more significant than that of low-energy sites after displacement. In addition, a decrease in sorption capacity after displacement could be ascribed to the partial depletion of sorption sites by the displacer. The displacement data indicated that the cocontaminant can have potential effects on the fate and bioavailability of anthropogenic organic pollutants sorbed in soils and sediments, thus affecting their exposure risks.

Geologic Sediments↗
PubMed2005

Neuroradiologic and clinicopathologic features of oculoleptomeningeal type amyloidosis.

OBJECTIVE: To clarify the pathogenesis of leptomeningeal amyloidosis in familial amyloidotic polyneuropathy amyloidogenic transthyretin Y114C (FAP ATTR Y114C). METHODS: The authors analyzed eight FAP ATTR Y114C patients. Six patients showed CNS symptoms associated with leptomeningeal amyloidosis. To examine the function of the blood-CSF barrier and blood-brain barrier (BBB), the authors performed CSF and MRI studies. The authors also performed a histopathologic study of autopsy specimens to examine the distribution of amyloid deposition in the CNS. RESULTS: CSF study showed high total protein concentrations and increased albumin CSF/serum concentration quotients (Qalb; an indication of blood-CSF barrier function). MRI with gadolinium (Gd) revealed enhancement from brainstem to spinal cord. Serial brain MRI studies with FLAIR images after Gd administration showed Gd leakage into the subarachnoid space (two patients). These findings suggested the blood-CSF barrier and BBB dysfunctions. Constructive interference in steady state (CISS) three-dimensional Fourier transformation (CISS-3DFT) sequence analysis demonstrated amyloid-induced funiculus structures joining the spinal cord and dura mater (one patient). Histopathologic study revealed intense amyloid deposition in leptomeninges, vessel walls, and parenchyma in spinal cord and the brain. These distributions of amyloid deposition are unique compared to other TTR related leptomeningeal amyloidosis. CONCLUSIONS: Patients with familial amyloidotic polyneuropathy amyloidogenic transthyretin Y114C had CNS disorders related to amyloid deposition in leptomeninges, vessel walls, and parenchyma in spinal cord and the brain. The pathogenesis of CNS disorders may reflect disruption of the blood-CSF barrier and blood-brain barrier by amyloid deposition.

Adult↗
PubMed2005

Fermi surface evolution and Luttinger theorem in Na(x)CoO2: a systematic photoemission study.

We report a systematic angle-resolved photoemission study on Na(x)CoO2 for a wide range of Na concentrations (0.3 < or = x < or = 0.72). In all the metallic samples at different x, we observed (i) only a single holelike Fermi surface centered around gamma and (ii) its area changes with x according to the Luttinger theorem. We also observed a surface state that exhibits a larger Fermi surface area. The e'(g) band and the associated small Fermi surface pockets near the K points predicted by band calculations are found to sink below the Fermi energy in a manner almost independent of the doping and temperature.

Journal Article↗
PubMed2005

Inhibition of intestinal cholesterol absorption by ezetimibe is a novel therapeutic target for fatty liver.

Ezetimibe is a novel lipid-lowering agent that inhibits intestinal absorption of dietary and biliary cholesterol. The effects of ezetimibe on low-density lipoprotein (LDL)-cholesterol were found to generally consistent across all subgroups analyzed, including baseline lipid profile, hypertension, diabetes mellitus, and body mass index. Furthermore, recent clinical studies also revealed that co-administration of ezetimibe with on-going statins offered a well-tolerated and efficacious treatment to lower LDL-cholesterol levels in hypercholesterolemic patients with diabetes mellitus or the metabolic syndrome. Niemann-Pick C1 like 1 (NPC1L1) protein is recently found to be critical for intestinal cholesterol absorption, and is a target protein for ezetimibe. Human NPC1L1 protein is predominantly expressed in liver, whereas small intestine expression is only about 2-4% of that found in the liver. Thus, NPC1L1 does not function solely in the intestinal cholesterol absorption. Furthermore, loss of NPC1L1 expression has been shown to protect against diet-induced fatty liver. These observations let us to speculate that ezetimibe will become a new therapeutic approach for the treatment of non-alcoholic fatty liver, the hepatic manifestation of insulin resistant patients with the metabolic syndrome. In this paper, we would like to propose the possible ways of testing our hypothesis as follows. (1) Does ezetimibe treatment improve fatty liver in patients with hypercholesterolemia or the metabolic syndrome? If the answers are yes, are these beneficial effects of ezetimibe superior to those of other anti-hyperlipidemic resins with equihypolipidemic properties? (2) Does ezetimibe treatment improve insulin sensitivity in fatty liver patients with the metabolic syndrome? (3) How about the effects of ezetimibe treatment on serum levels of adiponectin, a key adipokine with insulin-sensitizing property? Large clinical trials will provide us with more definite information whether ezetimibe treatment can improve fatty liver and resultantly reduce the risk of progression of liver diseases in patients with the metabolic syndrome.

Adiponectin↗
PubMed2005

Potential utility of statins, 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors in diabetic retinopathy.

Diabetic retinopathy is a common and potentially devastating microvascular complication in diabetes and is a leading cause of acquired blindness among the people of occupational age. However, therapeutic options for the treatment of proliferative diabetic retinopathy, photocoagulation and vitrectomy, are limited by considerable side effects. Therefore, to develop novel therapeutic strategies that specifically target diabetic retinopathy is desired for patients with diabetes. In diabetes mellitus, the formation and accumulation of advanced glycation end products (AGEs) progress. There is a growing body of evidence to show that AGEs-their receptor (RAGE) interactions are involved in the development and progression of diabetic retinopathy. Statins, 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors, have been recently shown to reduce the risk for cardiovascular events in diabetic patients with or without coronary artery disease. However, the efficacy of statin therapy for diabetic retinopathy is not fully investigated. We have recently found that protein prenylation is crucial for the AGE-RAGE signaling in microvascular endothelial cells. By blocking the protein prenylation, cerivastatin completely prevented the AGE-RAGE-elicited angiogenesis via suppression of vascular endothelial growth factor (VEGF). These observations let us to speculate that statins might be a promising remedy for treating patients with diabetic retinopathy by acting as a potential inhibitor of the AGE-RAGE signaling pathway in microvascular endothelial cells. In this paper, we would like to propose the possible ways of testing our hypotheses. (1) Does treatment with statins decrease the risk for the development and progression of diabetic retinopathy in patients with normocholesterolemia? (2) If the answer is yes, is this beneficial effect of statins superior to that of other cholesterol-lowering agents with equihypolipidemic properties? (3) Does statin treatment suppress retinal VEGF expression in diabetic patients? (4) Does treatment with pyridoxamine, a post-Amadori inhibitor of AGE formation, attenuate the beneficial effects of statins on diabetic retinopathy? These clinical studies could clarify whether the use of statins is of benefit in patients with AGE-RAGE-related disorders such as diabetic retinopathy, even in the absence of hypercholesterolemia.

Acyl Coenzyme A↗
PubMed2005

Protective role of pravastatin in the pathogenesis of the metabolic syndrome.

The metabolic syndrome is strongly associated with insulin resistance and consists of a constellation of factors such as hypertension and hyperlipidemia that raise the risk for cardiovascular diseases and diabetes mellitus. There is a growing body of evidence to show that 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors, statins, reduce cardiovascular-related morbidity and mortality in patients with or without coronary artery disease. Recent clinical observations argue for a simple strategy of considering routine statin therapy for patients with type 2 diabetes. Furthermore, statin therapy is also found to be effective in allowing LDL-cholesterol goal achievement in hypercholesterolemic high-risk patients with the metabolic syndrome. However, the effects of statins on the pathogenesis of the metabolic syndrome remain to be elucidated. Several types of statins are commercially available now. Among them, pravastatin is unique because it is the only statin that has been shown to have protective role against the development of diabetes in a large clinical trial. Moreover, a recent clinical study revealed that pravastatin treatment improved insulin sensitivity in 25 women with the metabolic syndrome with impaired glucose intolerance. These observations let us to speculate that pravastatin is a promising strategy for the treatment of hypercholesterolemic patients with the metabolic syndrome. It may improve the insulin sensitivity in these patients and subsequently prevent the development of type 2 diabetes. In this paper, we would like to propose the possible ways of testing our hypothesis as follows. (1) Does pravastatin treatment improve insulin resistance in patients of the metabolic syndrome or in insulin resistant hypertensive or obese patients? If the answers are yes, are these beneficial effects of pravastatin superior to those of other anti-hyperlipidemic statins with equihypolipidemic properties? (2) Does pravastatin treatment actually reduce the development of diabetes in these insulin resistant patients? At that time, does pravastatin treatment increase serum levels of adiponectin, a key adipokine with insulin-sensitizing property? How about the effects of pravastatin treatment on adipokines that could elicit insulin resistance such as tumor necrosis factor-alpha? These clinical studies will provide further information whether pravastatin treatment can improve insulin resistance and subsequently reduce the development of diabetes in insulin resistant patients with the metabolic syndrome.

Clinical Trials as Topic↗
PubMed2005

Regulation of neurokinin-1 receptor messenger RNA expression in synovial fibroblasts of patients with rheumatoid arthritis.

We examined whether soluble mediators regulate the expression of tachykinin receptor mRNAs in synovial fibroblasts of patients with rheumatoid arthritis (RA). mRNAs encoding long and short isomers of neurokinin 1 receptor (NK1R), and neurokinin 2 receptor (NK2R) were confirmed by reverse transcription-polymerase chain reaction (RT-PCR) analysis. Level of long, but not the short, of NK1R mRNA was increased by treatment with 10-100 ng/ml basic fibroblast growth factor (bFGF) or 20 ng/ml tumor necrosis factor-alpha (TNF-alpha), but not with 1ng/ml interleukin 1beta (IL-1beta). TNF-alpha upregulated NK2R mRNA as well as long NK1R mRNA whereas bFGF had no effect on NK2R mRNA. Expression of neurokinin 3 receptor (NK3R) mRNA was not observed in RA fibroblasts, and its expression was not induced by bFGF and TNF-alpha. The basal and increased levels of long NK1R mRNA were inhibited by treatment with 20 microM SU5402, an inhibitor of the tyrosine kinase activity of FGF receptor 1 (FGFR1), or 10 ng/ml transforming growth factor-beta1 (TGF-beta1). SU5402 and TGF-beta1 had no effect on the basal level of short NK1R mRNA. Immunocytochemistry revealed the enhancement by bFGF of immunoreactive NK1Rs in the cells at 24 h after treatment. These results suggest that bFGF, TGF-beta1, and TNF-alpha in synovial tissue and fluid play a role in the regulation of long NK1R expression in synovial fibroblasts of RA patients. It appears that the pathway of downregulation by TGF-beta1 is more dominant in the long NK1R mRNA expression than that of upregulation by bFGF or TNF-alpha. Furthermore, the regulation of short NK1R mRNA expression seems to be performed via a different pathway from that of long isomer mRNA.

Arthritis, Rheumatoid↗
PubMed2005

Characterization of cDNA and the genomic sequence encoding canine neural-cell adhesion molecule, CD56/N-CAM.

The neural-cell adhesion molecule, CD56/N-CAM is a member of the immunoglobulin superfamily expressed by various tissues and cells, including natural killer (NK) cells. Despite the importance of CD56 as a marker for identifying NK cells in circulating blood, canine CD56 has not been identified. In the present study, we identified the canine counterparts of the 140-kDa (CD56-140) and 120-kDa (CD56-120) isoforms of human DC56. Both of amino acid sequences encoded by the canine CD56-140 and -120 cDNA showed high homology with those of human (both 96% homology), having well-conserved domains (five immunoglobulin, two fibronectin type III, and transmembrane and intracellular or glycosylphosphatidylinositol-linked domain) among various species (human, mouse, and feline). We revealed that the transcripts of canine CD56-140 and -120 arise from alternative mRNA splicing from a single gene located on canine chromosome 5. Moreover, the mRNA encoding canine CD56-140 was expressed at high levels constitutively by nervous system and endocrine tissues as has shown in other animals.

Alternative Splicing↗
PubMed2005

Angle-resolved photoemission spectroscopy study of adsorption process and electronic structure of silver on ZnO(1010).

The adsorption process and valence band structure of Ag on ZnO(1010) have been investigated by angle-resolved photoelectron spectroscopy utilizing synchrotron radiation. The coverage-dependent measurements of the Ag 4d band structure reveal that the Ag bands with a dispersing feature are formed even at low coverages and that the basic structure of the bands is essentially the same throughout the submonolayer region. These results indicate that the Ag atoms aggregate to form islands with an atomically ordered structure from the low coverages. Upon annealing the Ag-covered surface at 900 K, the Ag 4d band undergoes only a minor change, suggesting that the ordered structure within the Ag islands is persistent against mild annealing. From the dispersive feature of the Ag 4d states, we propose that the atomic structure has locally rectangular symmetry with a good lattice matching with the ZnO(1010) surface.

Journal Article↗
PubMed2005

Strategy of treatment of submucosal gastric tumors.

BACKGROUND: The more frequent use of endoscopic ultrasonography (EUS) leads to an increased number of diagnosed gastric submucosal tumors (G-SMT). Since until now rather little therapeutical success in respect of these tumors has been achieved, we evaluated our concept of watchful waiting and selective treatment of patients with G-SMT in an analysis of prospectively collected data. PATIENTS AND METHODS: Forty-seven consecutive patients with G-SMT treated at our institution between 1994 and 2000, were included. All patients underwent abdominal ultrasound and EUS, and in case of suspicious findings or a tumor size > 2 cm EUS fine needle aspiration (EUS-FNA) was performed. Patients were operated on if a malignant tumor was suspected (tumor size > 2 cm; detection of metastases) or if complications occurred (e.g. bleeding, ulceration). RESULTS: All 47 patients were included in this study. Typical symptoms were nausea (64%), bleeding (11%) and pain (9%). EUS showed a G-SMT averaging 6.4 (0.8 - 30) cm in size. EUS-FNA was performed in 24 patients revealing PAP III (n = 1), PAP II (n = 21) and PAP I (n = 2) scores. Surgery was performed in 33 patients, revealing gastrointestinal stromal tumors (GISTs) in 18 patients as well as several other malignant and non-malignant lesions. During follow-up (median 37 months), none of the conservatively treated patients (n = 14) developed a malignant tumor. CONCLUSIONS: In one third of our patients surgery could be avoided with this strategy. No delayed diagnosis of a malignant tumor during follow-up was established. Small G-GMT's should be monitored conservatively if diagnostic procedures and follow-up was performed by EUS and eventually EUS-FNA.

Adult↗
PubMed2005

Direct observation of a nonmonotonic dx2-y2- wave superconducting gap in the electron-doped high-Tc superconductor Pr0.89LaCe0.11CuO4.

We performed high-resolution angle-resolved photoemission spectroscopy on electron-doped high-Tc superconductor Pr0.89LaCe0.11CuO4 to study the anisotropy of the superconducting gap. The observed momentum dependence is basically consistent with the dx2-y2- wave symmetry, but obviously deviates from the monotonic dx2-y2- gap function. The maximum gap is observed not at the zone boundary, but at the hot spot where the antiferromagnetic spin fluctuation strongly couples to the electrons on the Fermi surface. The present experimental results suggest the spin-mediated pairing mechanism in electron-doped high-Tc superconductors.

Journal Article↗
PubMed2005

p53 prevents maturation of T cell development to the immature CD4-CD8+ stage in Bcl11b-/- mice.

Signaling pathways such as the pre-TCR and Wnt pathways regulate alpha/beta T cell differentiation in thymus. Mice lacking an essential component of the pre-TCR exhibit arrest at the (CD4(-)CD8(-)) (CD44(-)CD25(+)) stage (DN3) of thymocyte development, and introduction of p53 deficiency into those mice abrogates this arrest, resulting in transition to the (CD4(+)CD8(+)) double-positive (DP) stage. This paper examines the effect of inactivation of p53 on thymocyte development in Bcl11b(-/-) mice that exhibit arrest at the DN3 or (CD4(-)CD8(+)) immature single-positive (ISP) stage. No DP thymocytes were detected in thymocytes of adoptive transfer experiments in scid mice that were derived from p53(-/-)Bcl11b(-/-) precursors but ISP thymocytes increased in the proportion and in the cell number approximately three times higher than those from Bcl11b(-/-) precursors. Consistently, the level of apoptosis decreased to the level of wild-type precursors. These results suggest that inactivation of p53 is sufficient for DN3 thymocytes to differentiate into the ISP, but not to DP, stage of thymocyte development in Bcl11b(-/-) mice. This provides evidence for a novel p53-mediated checkpoint that regulates the transition from the DN3 to ISP stage of thymocyte development.

Animals↗
PubMed2005

Clinical diagnosis of MM2-type sporadic Creutzfeldt-Jakob disease.

BACKGROUND: No method for the clinical diagnosis of MM2-type sporadic Creutzfeldt-Jakob disease (sCJD) has been established except for pathologic examination. OBJECTIVE: To identify a reliable marker for the clinical diagnosis of MM2-type sCJD. METHODS: CSF, EEG, and neuroimaging studies were performed in eight patients with MM2-type sCJD confirmed by neuropathologic, genetic, and western blot analyses. RESULTS: The eight cases were pathologically classified into the cortical (n = 2), thalamic (n = 5), and combined (corticothalamic) (n = 1) forms. The cortical form was characterized by late-onset, slowly progressive dementia, cortical hyperintensity signals on diffusion-weighted imaging (DWI) of brain, and elevated levels of CSF 14-3-3 protein. The thalamic form showed various neurologic manifestations including dementia, ataxia, and pyramidal and extrapyramidal signs with onset at various ages and relatively long disease duration. Characteristic EEG and MRI abnormalities were almost absent. However, all four patients examined with cerebral blood flow (CBF) study using SPECT showed reduction of the CBF in the thalamus as well as the cerebral cortex. The combined form had features of both the cortical and the thalamic forms, showing cortical hyperintensity signals on DWI and hypometabolism of the thalamus on [18F]2-fluoro-2-deoxy-d-glucose PET. CONCLUSION: For the clinical diagnosis of MM2-type sporadic Creutzfeldt-Jakob disease, cortical hyperintensity signals on diffusion-weighted MRI are useful for the cortical form and thalamic hypoperfusion or hypometabolism on cerebral blood flow SPECT or [18F]2-fluoro-2-deoxy-d-glucose PET for the thalamic form.

14-3-3 Proteins↗
PubMed2005

Interferon beta-1b is effective in Japanese RRMS patients: a randomized, multicenter study.

OBJECTIVE: To assess the efficacy of interferon beta-1b (IFNB-1b) in Japanese patients with relapsing-remitting multiple sclerosis (RRMS). BACKGROUND: The effects of IFNB in RRMS have been assessed in study populations comprised predominantly of white patients. MS in Japanese patients is different from that in white patients in that there are two different presentations--classic MS (C-MS) and optic-spinal MS (OS-MS)--and chronic progressive forms are infrequent. METHODS: A total of 205 Japanese patients with RRMS were randomized to receive 50 microg or 250 microg (1.6 or 8.0 MIU) IFNB-1b administered SC every other day for up to 2 years. The primary endpoint was annual relapse rate. Secondary endpoints included further relapse-related and MRI outcome measures, as well as changes in Expanded Disability Status Scale and Neurologic Rating Scale. Efficacy was assessed in 188 patients, and safety was assessed in 192 patients. Supplemental ad hoc subgroup analyses were also performed for patients with OS-MS and those with C-MS. RESULTS: Annual relapse rates were 0.763 in the 250 microg group and 1.069 in the 50 microg group, a relative reduction of 28.6% (p = 0.047). Results for all secondary endpoints favored 250 microg IFNB-1b. Subgroup analyses suggested that the magnitude and direction of treatment effect in patients with OS-MS and C-MS was similar, albeit not significant due to small sample size. CONCLUSIONS: Interferon beta-1b (IFNB-1b) 250 microg significantly reduced relapse rates and change in MRI lesion area in Japanese patients with relapsing-remitting multiple sclerosis, and seemed to be comparably effective in optic-spinal multiple sclerosis (MS) and classic MS. The response to treatment with IFNB-1b in Japanese patients with MS suggests that a common pathogenesis and underlying genetic characteristics are shared with white patients.

Adolescent↗