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Y Sato

Publications and source records attributed to Y Sato.

At least 37 records · Page 2Linked to original sources
PubMed2006

Endoscopic in vivo evaluation of tissue atypia in the esophagus using a newly designed integrated endocytoscope: a pilot trial.

BACKGROUND AND STUDY AIMS: A newly designed magnifying endoscope featuring an endocytoscopy function provided by ultrahigh magnification was evaluated in a pilot study in patients with various types of benign and malignant pathology in the esophagus. PATIENTS AND METHODS: Seventy-five consecutive patients were included in the study from 15 March to 21 December 2005. Twenty-nine patients with specific esophageal lesions that had been detected by regular or narrow-band imaging, or both, were further evaluated using endocytoscopy, followed by tissue biopsy or resection. During the endocytoscopic examinations, the esophageal mucosa was stained with 0.5 % methylene blue. The endocytoscopic findings were graded from 1 to 5 in an endocytoscopic atypia (ECA) classification. The final histopathological diagnoses based on biopsies or resected specimens were as follows: category 1 in the Vienna classification, n = 4; category 2, n = 6; category 3, n = 1; category 4, n = 10; and category 5, n = 7. The endocytoscopic diagnoses were compared with the histopathological diagnoses. RESULTS: Clear endocytoscopic images were obtained in all cases. In definitely malignant lesions, the cell nuclei had an enlarged and irregularly arranged appearance (grade ECA 5). The positive predictive value for malignancy (grades ECA 4 and 5) was 94 %; the false-negative rate was 16.7 %, and the false-positive rate was 6.3 %. The overall accuracy of endocytoscopy for differentiating between nonmalignant tissue (categories 1 - 3 in the Vienna classification) and malignant tissue (categories 4 and 5) was 82 %. CONCLUSIONS: These preliminary results suggest that incorporating endocytoscopy facilities into a standard endoscope may be helpful in characterizing tissue in a variety of esophageal lesions. The potential clinical impact of this method in relation to other gastrointestinal organs requires further study.

Carcinoma, Squamous Cell↗
PubMed2006

Fatal hepatitis B virus reactivation in a chronic myeloid leukemia patient during imatinib mesylate treatment.

Reactivation of chronic hepatitis B virus (HBV) infection in patients undergoing chemotherapy is well-documented, but reactivation during imatinib mesylate treatment has not been reported. This study reports a 54-year-old man, without prior liver dysfunction but with chronic HBV infection, in whom fatal HBV reactivation occurred during treatment of chronic myeloid leukemia (CML) with imatinib mesylate. He developed fulminant hepatitis followed by marked elevation of HBV DNA polymerase, probably from the lymphocytopenic and immunosuppressive status induced by imatinib mesylate. Imatinib mesylate is widely used to treat CML patients. Although therapy with imatinib mesylate is generally well tolerated, the case presented here suggests that viral reactivation should be considered, even when using imatinib mesylate to treat CML.

Antineoplastic Agents↗
PubMed2006

Identification of a glucan-binding protein C gene homologue in Streptococcus macacae.

BACKGROUND/AIMS: The past few decades have seen the isolation of certain glucosyltransferases and a number of proteins from mutans streptococci. Some of these proteins have been shown to possess glucan-binding capabilities which confer an important virulence property on mutans streptococci for the role of these bacteria play in dental caries. Among these proteins is glucan-binding protein C, which is encoded by the gbpC gene, and which we have identified as being involved in the dextran-dependent aggregation of Streptococcus mutans. However, gbpC homologues have yet to be identified in other mutans streptococci. METHODS: We carried out polymerase chain reaction amplification of Streptococcus macacae using primers that were designed based on conserved sequences of S. mutans gbpC and identified a gbpC gene homologue. The gene of that homologue was then characterized. RESULTS: Nucleotide sequencing of the S. macacae gbpC homologue revealed a 1854 bp open reading frame encoding a protein with an N-terminal signal peptide. The molecular mass of the processed protein was calculated to be 67 kDa. We also found an LPxTG motif, the consensus sequence for gram-positive cocci cell wall-anchored surface proteins, which was followed by a characteristic sequence at the carboxal terminal region of the putative protein. This suggests that the S. macacae GbpC homologue protein was tethered to the cell wall. CONCLUSION: Based on these results, together with the demonstrated glucan-binding ability of the S. macacae GbpC homologue protein, we suggest that S. macacae cells are capable of binding dextran via the GbpC homologue protein, which is similar to the S. mutans GbpC protein. In addition, Southern hybridization analysis using the S. macacae gbpC homologue as a probe showed a distribution of gbpC homologues throughout the mutans streptococci.

Amino Acid Motifs↗
PubMed2006

Genetic background differences between FVB and C57BL/6 mice affect hypnotic susceptibility to pentobarbital, ketamine and nitrous oxide, but not isoflurane.

BACKGROUND: Pharmacogenomics has allowed us to identify the mechanisms underlying much of the inherited variability in drug response. There have been several reports of strain-dependent anesthetic actions in rodents, indicating that significant genetic differences exist in the hypnotic and antinociceptive effects of various anesthetics. METHODS: Loss of righting reflex was used to compare the hypnotic action of pentobarbital, ketamine, nitrous oxide and isoflurane between two genetically different populations of mice, C57BL/6 with black hair and Friends virus B (FVB) with white hair. RESULTS: C57BL/6 mice were more susceptible than FVB mice to the hypnotic effects of ketamine, pentobarbital and nitrous oxide. However, the sensitivity to isoflurane did not differ between C57BL/6 and FVB mice. CONCLUSION: Genetic background affects the hypnotic susceptibility to some anesthetic agents in mice. Our results indicate that there may be a different genetic basis for the operation of hypnosis between isoflurane and other anesthetics, such as pentobarbital, ketamine and nitrous oxide.

Anesthetics, Dissociative↗
PubMed2006

[Prognosis of patients after resection for lung cancer with intrapulmonary metastasis in different lobes].

BACKGROUND: The prognosis of lung cancer patients with intrapulmonary metastasis in different lobes (pm2) is poor. However, some patients achieve long-term survival. We retrospectively investigated the prognosis of resected primary lung cancer patients with pm2. METHOD: Among 845 patients with primary lung cancer who underwent complete resection from 1984 to 2003, 14 cases that had lung cancer with pm2 were evaluated about prognostic factors. RESULTS: The overall 5-year survival rate was 9.5%. The analysis of survival curve based on clinicopathological factors (surgical procedure, histology, tumor size, lymph nodal metastasis, pleural invasion, pleural dissemination and number of pm2) revealed that bronchioloalveolar carcinoma (BAC), the absence of pleural invasion and the absence of pleural dissemination are better prognostic factors. CONCLUSION: Lung cancer patients with pm2 whose lesions show BAC histology, the absence of pleural invasion or pleural dissemination may achieve long-term survival and could be candidates for surgical treatment.

Adenocarcinoma, Bronchiolo-Alveolar↗
PubMed2006

[Left atrial myxoma combined with coronary artery bypass grafting].

We experienced 2 cases of surgical treatment for left atrial myxoma combined with coronary artery bypass grafting (CABG) using only in situ arterial grafts. A 58-year-old man who had undergone CABG [left internal thoracic artery (LITA)-right coronary artery (RCA) and saphenous vein graft (SVG)-left anterior descending artery (LAD)] 14 years before was admitted to our hospital, complaining of anterior chest pain. Coronary arteriography demonstrated total occlusion of the LAD and RCA, as well as the stenosis of high lateral branch (HL) and SVG. Left atrial myxoma was incidentally detected by echocardiography. Myxoma was resected at first, and then the right internal thoracic artery (RITA) was anastomosed to the LAD. The postoperative course was uneventful. A 69-year-old woman was admitted to another hospital, complaining of chest pain and dyspnea. Coronary arteriography revealed stenosis of LAD, left circumflex artery (LCx) and HL, as well as left main trunk (LMT). Left atrial myxoma was incidentally detected by echocardiography. Myxoma was resected at first, and then CABG [LITA-HL, gastroepiploic artery (GEA)-RCA and RITA-LAD] was carried out. The postoperative course was uneventful. The priority between CABG and the surgical treatment for cardiac myxoma remains controversial from the point of view of myocardial protection and prevention of systemic embolism of myxomal fragment.

Aged↗
PubMed2005

An in vitro study of long-term potentiation in the carp (Cyprinus carpio L.) olfactory bulb.

Long-term potentiation (LTP) of synaptic transmission is considered a cellular mechanism for neural plasticity and memory formation. Previously, we showed that in the carp olfactory bulb, LTP occurs at the dendrodendritic mitral-to-granule cell synapse following tetanic electrical stimulation applied to the olfactory tract, and suggested that it is involved in the process of olfactory memory formation. As a first step towards understanding mechanisms underlying plasticity at this synapse, we examined the effects of various drugs (glutamate and GABA receptor agonists and antagonists, noradrenaline, and drugs affecting cAMP signaling) on dendrodendritic mitral-to-granule cell synaptic transmission in an in vitro preparation. Two forms of LTP are involved: a postsynaptic form (tetanus-evoked LTP) and a presynaptic form. The postsynaptic form is evoked at the granule cell dendrite following tetanic olfactory tract stimulation and is suppressed by the NMDA receptor antagonist, D-AP5, enhanced by noradrenaline, and occluded by the metabotropic glutamate receptor agonist, trans-ACPD. The presynaptic form occurs at the mitral cell dendrite following blockade of the GABA(A) receptor by picrotoxin and bicuculline, or via activation of cAMP signaling by forskolin and 8-Br-cAMP.

Action Potentials↗
PubMed2005

Screening of novel nuclear receptor agonists by a convenient reporter gene assay system using green fluorescent protein derivatives.

Nuclear receptors represent a very good family of protein targets for the prevention and treatment of diverse diseases. In this study, we screened natural compounds and their derivatives, and discovered ligands for the retinoic acid receptors (RARs) and the farnesoid X receptor (FXR). In the reporter assay systems of nuclear receptors presented here, two fluorescent proteins, enhanced yellow fluorescent protein (EYFP) and enhanced cyan fluorescent protein (ECFP), were used for detection of a ligand-based induction and as an internal control, respectively. By optimizing the conditions (e.g., of hormone response elements and promoter genes for reporter plasmids), we established a battery of assay systems for ligands of RARs, retinoid X receptor (RXR) and FXR. The screening using the reporter assay system can be carried out without the addition of co-factors or substrates. As a result of screening of more than 140 compounds, several compounds were detected which activate RARs and/or FXR. Caffeic acid phenylethyl ester (CAPE), known as a component of propolis from honeybee hives, and other derivatives of caffeic acid up-regulated the expression of reporter gene for RARs. Grifolin and ginkgolic acids, which are non-steroidal skeleton compounds purified from mushroom or ginkgo leaves, up-regulated the expression of the reporter gene for FXR.

Animals↗
PubMed2005

Mapping of QTL associated with chilling tolerance during reproductive growth in soybean.

Low temperatures in summer bring about drastic reduction in seed yield of soybean [Glycine max (L.) Merr.]. To identify quantitative trait loci (QTL) associated with chilling tolerance during the reproductive growth in soybean, a recombinant inbred line (RIL) population consisting of 104 F(6)-derived lines was created from a cross between two cultivars, chilling-tolerant Hayahikari and chilling-sensitive Toyomusume. The RIL were genotyped with 181 molecular and phenotypic markers and were scored with regard to chilling tolerance, which was evaluated by comparison of seed-yielding abilities in two artificial climatic environments at chilling and usual temperatures. Three QTL were detected for chilling tolerance in seed-yielding ability. Two of them, qCTTSW 1 and qCTTSW 2, were mapped near QTL for flowering time, and the latter had an epistatic interaction with a marker locus located near another QTL for flowering time, where no significant QTL for chilling tolerance was detected. The analysis of an F(2) population derived from the cross between Hayahikari and an RIL of the Hayahikari genotype at all QTL for flowering time confirmed the effect of the third QTL, qCTTSW 3, on chilling tolerance and suggested that qCTTSW 1 was basically independent of the QTL for flowering time. The findings and QTL found in this study may provide useful information for marker-assisted selection (MAS) and further genetic studies on soybean chilling tolerance.

Acclimatization↗
PubMed2005

Perivascular infiltrate of memory lymphocytes and mature dendritic cells in MG thymomas.

In thymomas associated with myasthenia gravis (MG), the authors found that perivascular infiltrates of memory lymphocytes and mature dendritic cells (DCs) were more frequent in patients with early improvement after thymectomy than in patients without response to thymectomy. Although these findings may be limited to particular types of thymoma, thymectomy may interrupt the recruitment of mature DCs in thymus and export of activated T cells to extra-thymic tissues, thereby improving the disease.

Aged↗
PubMed2005

Umbilical arterial thrombosis with vascular wall necrosis: clinicopathologic findings of 11 cases.

Thrombosis of umbilical cord vessels is associated with a high perinatal mortality. Most cases are venous thrombi, arterial thrombi are uncommon. To clarify clinical and pathological features of this entity, we reviewed 11 cases with umbilical artery thrombosis. The gestational ages were 33-40 (mean 36.8) weeks. Three cases (38%) were associated with severe intrauterine growth retardation and two cases (25%) led to intrauterine fetal deaths. All cases had completely occlusive thrombi of one umbilical artery. The arteries with thrombosis demonstrated partial necrosis of vascular wall. The pathogenesis is unclear, but nine cases (82%) had cord abnormalities (long cord, peripheral cord insertion, short cord with twist, funisitis). This paper is the first report of clinical and pathological features of umbilical artery thrombosis. The results of this study confirm the clinical importance and unique histological findings of umbilical artery thrombosis. The recognition of umbilical artery thrombosis is necessary to establish the diagnosis and treatment of this condition.

Adult↗
PubMed2005

Effects of vitamin K2 administration on calcium balance and bone mass in young rats fed normal or low calcium diet.

OBJECTIVE: The purpose of this study was to examine the effects of vitamin K2 administration on calcium balance and bone mass in young rats fed a normal or low calcium diet. METHODS: Forty female Sprague-Dawley rats, 6 weeks of age, were randomized by stratified weight method into four groups with 10 rats in each group: 0.5% (normal) calcium diet, 0.1% (low) calcium diet, 0.5% calcium diet + vitamin K2 (menatetrenone, 30 mg/100 g chow diet), and 0.1% calcium diet + vitamin K2. After 10 weeks of feeding, serum calcium and calciotropic hormone levels were measured, and intestinal calcium absorption and renal calcium reabsorption were evaluated. Bone histomorphometric analyses were performed on cortical bone of the tibial shaft and cancellous bone of the proximal tibia. RESULTS: Feeding a low calcium diet induced hypocalcemia, increased serum parathyroid hormone (PTH) and 1,25-dihydroxyvitamin D [1,25(OH)2D] levels with decreased serum 25-hydrovyvitamin D [25(OH)D] level, stimulated intestinal calcium absorption and renal calcium reabsorption, and reduced cortical bone mass as a result of decreased periosteal bone gain and enlarged marrow cavity, but did not significantly influence cancellous bone mass. Vitamin K2 administration in rats fed a low calcium diet stimulated renal calcium reabsorption, retarded the abnormal elevation of serum PTH level, increased cancellous bone mass, and retarded cortical bone loss, while vitamin K2 administration in rats fed a normal calcium diet stimulated intestinal calcium absorption by increasing serum 1,25(OH)2D level, and increased cortical bone mass. CONCLUSION: This study clearly shows the differential response of calcium balance and bone mass to vitamin K2 administration in rats fed a normal or low calcium diet.

Animals↗
PubMed2005

Production of the neutron-rich hypernucleus 10LambdaLi in the (pi-,K+) double charge-exchange reaction.

In order to produce a neutron-rich Lambda hypernucleus for the first time, we carried out an experiment by utilizing the (pi-,K+) double charge-exchange reaction on a 10B target. We observed the production of a 10LambdaLi hypernucleus. The cross section for the Lambda bound region was found to be 11.3+/-1.9 nb/sr with the 1.2 GeV/c incident momentum, which is compared with the 10LambdaB hypernucleus production cross section, 7.8+/-0.3 microb/sr, in the (pi+,K+) reaction with a 1.05 GeV/c incident momentum beam.

Journal Article↗
PubMed2005

Investigation of the conjectured nucleon deformation at low momentum transfer.

We report new precise H(e,e(')p)pi(0) measurements at the Delta(1232) resonance at Q(2)=0.127 (GeV/c)(2) obtained at the MIT-Bates out-of-plane scattering facility which are particularly sensitive to the transverse electric amplitude (E2) of the gamma(*)N-->Delta transition. The new data have been analyzed together with those of earlier measurements to yield precise quadrupole to dipole amplitude ratios: Re(E(3/2)(1+)/M(3/2)(1+))=(-2.3+/-0.3(stat+syst)+/-0.6(model))% and Re(S(3/2)(1+)/M(3/2)(1+))=(-6.1+/-0.2(stat+syst)+/-0.5(model))% for M(3/2)(1+)=(41.4+/-0.3(stat+syst)+/-0.4(model))(10(-3)/m(pi(+))). The derived amplitudes give credence to the conjecture of deformation in hadrons favoring, at low Q2, the dominance of mesonic effects.

Journal Article↗
PubMed2005

A case of gastrointestinal stromal tumour of the ampulla of Vater.

Gastrointestinal stromal tumour rarely develops in the duodenal ampulla region. We report here a case of gastrointestinal stromal tumour of the ampulla of Vater found in a 44-year-old Japanese man presenting with biliary obstruction. He died of hepatic failure with diffuse liver metastasis. The postmortem examination showed a large Borrman type III-like tumour in the duodenal ampullary region with direct invasion of the pancreas and extrahepatic bile duct as well as metastases to the liver and regional lymph nodes. The duct orifice was located at the centre of the tumour. Microscopically, the tumour consisted of anaplastic spindle cells with high mitotic activity (90 mitoses per 50 high-power fields). Immunohistochemically, the spindle cells were positive for KIT and CD34. The final diagnosis was high-grade malignant gastrointestinal stromal tumour of the ampulla of Vater. Considering the recent advances in the diagnosis and treatment of gastrointestinal stromal tumour, this neoplasm should be included in the differential diagnosis of the tumours appearing in the duodenal ampulla region.

Adult↗
PubMed2005

Capsid protein genetic analysis and viral spread to the spinal cord in cats experimentally infected with feline calicivirus (FCV).

We investigated primitively the molecular basis of the neural spread of a feline calcivirus isolate (FCV-S) from the spinal cord of a cat that died after manifesting excitation. Experimental infections of cats with three clones from parent virus isolate FCV-S, isolated based on plaque size, were performed, and virus recovery from the spinal cord and the nucleotide and predicted amino acid sequences of the viral capsid protein region (ORF2) were compared. In the experimental infection with the one-time cloned virus (C1L1) isolated from a large plaque, the C1L1 was recovered from the spinal cord. In contrast, seven-times cloned C6L7 (from large plaque) and five-times cloned C5S2 (isolated from small plaque) were not recovered from the spinal cord. Genetic analysis of the capsid protein gene of the three viral clones revealed that four bases were different and two amino acids were different at positions 34 (Val in C6L7 and Ala in C1L1 and C5S2) and 46 (Leu in C6L7 and Pro in C1L1 and C5S2) between C6L7 (with large plaque) and C5S2 (with small plaque). The amino acid at position 434 of C1L1 was different from those of C6L7 and C5S2 (Gly in C1L1, D (Asp) in C6L7 and C5S2). From these results, the plaque size seemed not to be related to the spread of virus to the spinal cord. Clone C1L1, which spread to the spinal cord, had a difference of one amino acid from the other two clones, which may be related to the ability to spread to the spinal cord.

Amino Acid Sequence↗
PubMed2005

Assessment of talus deformity by three-dimensional MRI in congenital clubfoot.

PURPOSE: To evaluate the morphological deformity of talus in congenital clubfoot by three-dimensional MRI. MATERIAL AND METHOD: Subjects were five patients (two male, three female, mean age 5 months) with unilateral congenital clubfoot. Magnetic resonance imaging was performed of both feet using 1.5 T magnet. Based on the resulting magnetic resonance imaging volume data, a three-dimensional surface bone model was reconstructed by the Marching Cubes method. The long axis of the reconstructed model was determined, and in relation to the standard planes including this axis, the degree of talar head and neck deviation, and the relative positioning of the talus and navicular in the talonavicular joint were compared between normal foot and clubfoot. RESULT: The talar head and neck angle in relation to the talus exhibited significant medial deviation in the clubfoot, but the degree of plantar deviation of the talar head and neck did not show significance. The navicular was located more medially in clubfoot than in normal foot. The volume of the total talar and of the ossific nucleus for the clubfoot was smaller than that for the normal foot. CONCLUSION: The assessment technique presented herein was shown to be useful in ascertaining the various pathological characteristics associated with clubfoot.

Ankle Joint↗