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Biomedical subjects

T Matsuoka

Publications and source records attributed to T Matsuoka.

At least 37 records · Page 2Linked to original sources
PubMed2003

Novel optical and magnetic bistability and photoinduced transition in a one-dimensional halogen-bridged binuclear pt complex.

In iodine-bridged binuclear Pt compounds, R(4)[Pt(2)(pop)(4)I]nH(2)O and R(')(2)[Pt(2)(pop)(4)I]nH(2)O (pop=P(2)O5H2-2), electronic structures on the PtPtI chains have been controlled between a diamagnetic charge-density-wave (CDW) state and a paramagnetic charge-polarization (CP) state by modification of the counterions (R, R') located between chains. In the R=(C2H5)2NH+2 compound, a pressure-induced CP to CDW transition with a drastic color change is identified. This transition is accompanied by a large hysteresis loop within which photoinduced transition between CDW and CP can be driven by selecting the excitation photon energy.

Journal Article↗
PubMed2003

[Subjective criteria of chest CT findings for predicting pathological features and postoperative outcomes of small peripheral lung cancer (< or = 2 cm)].

One hundred fifty five patients with completely resected peripheral non-small cell lung cancer, clinically diagnosed 2 cm or less in diameter, are retrospectively reviewed on their preoperative chest CT films, clinico-pathological features, and postoperative outcomes. Pathologic type was classified according to Noguchi's classification. 7% and 8% of all the patients had pathologic N 1 and N 2 diseases, respectively. 19% of all the patients undergone limited resection (segmentectomy or partial resection). Maximum area of the tumor/soft tissue density area of the tumor (M/S ratio) was manually measured by chest CT film. According to the logistic regression analysis, M/S ratio was the only predicting factor of regional lymph node metastasis among factors including pleural indentation, spiculation, and maximum area of the tumor. Univariate analysis showed that maximum area of the tumor, pleural indentation, and M/S ratio were the significant factor for postoperative disease free survival. According to multivariate analysis of postoperative disease free survival with adjustment for operative modality, the result was same as that of univariate analysis. In conclusion, our determined criteria of the chest CT accurately predicted pathological status and postoperative outcome of patients with small peripheral lung cancer. These factors would be useful for stratification factor of prospective clinical study.

Aged↗
PubMed2002

Long-term response to zonisamide in patients with West syndrome.

The long-term effectiveness of zonisamide (ZNS) was evaluated in 11 patients with West syndrome (7 symptomatic) who had cessation of spasms with ZNS monotherapy. During the follow-up period (24 to 79 months, mean = 53 months), this response was maintained in 7 patients (3 symptomatic, relapse rate = 36%), including 2 children in whom ZNS was successfully discontinued. No serious adverse reactions were noted. ZNS may be both effective and well tolerated for the treatment of West syndrome.

Adolescent↗
PubMed2002

Absence of edge localized moments in the doped spin-Peierls system CuGe1-xSixO3.

We report the observation of nuclear quadrupole resonance (NQR) of Cu from the sites near the doping center in the spin-Peierls system CuGe 1-xSixO3. The signal appears as the satellites in the Cu NQR spectrum, and has a suppressed nuclear spin-lattice relaxation rate indicative of a singlet correlation rather than an enhanced magnetic correlation near the doping center. Signal loss of Cu nuclei with no neighboring Si is also observed. We conclude from these observations that the doping-induced moments are not in the vicinity of the doping center but rather away from it.

Journal Article↗
PubMed2002

Cardiovascular response to acute hypoxemia in adult rats hypoxemic neonatally.

OBJECTIVE: To determine the effects of chronic hypoxemia neonatally on the cardiovascular response to acute hypoxemia in adulthood. METHODS: Experiments were conducted on adult rats (82+/-2 days) which had been made chronically hypoxemic (hypobaric hypoxia equivalent to FiO(2)=0.14) during the first ten days of life but raised in room air (Neonatally Hypoxemia) as well as on adult rats never previously hypoxemic (Control). The animals were instrumented with catheters in the right common carotid artery and superior vena cava for measurements of mean systemic arterial pressure (MAP), central venous pressure, heart rate (HR), arterial blood gases, and arterial as well as mixed venous O(2) saturation. Oxygen consumption (VO(2)) was measured allowing calculation of cardiac index (CI), stroke volume index (SVI) and systemic vascular resistance index (SVRI). The rats were made acutely hypoxemic by exposure to FiO(2)=0.10 for 20 min. RESULTS: HR increased and MAP decreased to similar extents in both groups during acute hypoxemia. However, SVI and CI increased significantly (P<0.05) during acute hypoxemia in the Neonatally Hypoxemic group (24+/-6%, 41+/-8%) but respectively decreased and did not change in the Control animals (-13+/-6%, 2+/-6%). SVRI fell significantly more during hypoxemia in the Neonatally Hypoxemic animals than in the Control group (36+/-4% vs. 14+/-5%). CONCLUSIONS: Hypoxemia experienced in early life has long-term effects on the cardiovascular response to acute hypoxemia at maturity. This may have important implications for individuals hypoxemic in early life due to congenital cyanotic heart defects or pulmonary disease secondary to prematurity.

Animals↗
PubMed2002

Ecdysteroid-dependent expression of a novel cuticle protein gene BMCPG1 in the silkworm, Bombyx mori.

When insects molt, the exoskeleton is renewed under the controls of insect hormones via the biosynthesis and degradation of cuticle proteins. To understand the hormonal control of cuticle formation, we used the differential display method to look for stage-specific cuticle genes, and identified a novel cDNA named Bombyx mori Cuticle Protein GlyGlyTyr-repeat 1 (BMCPG1). Expression of BMCPG1 mRNA peaked sharply immediately after a pulse of ecdysteroid during the fourth molt and pre-pupal stages, concurrent with the expression of genes for FTZF1 and dopa decarboxylase. BMCPG1 was expressed only in the epidermis, but not in any other tissue. We cultured the larval epidermis and found that BMCPG1 expression is not induced by the continuous presence of ecdysteroid. Removal of ecdysteroid from the medium, which constitutes a pulse treatment, is required for the induction of BMCPG1 transcription. These results explain well the stage-specific expression of BMCPG1 by ecdysteroid in vivo. Based on its expression patterns and unique structure, we propose that BMCPG1 may be a novel component of epicuticle of B. mori, and is probably involved in cross-linking of proteins via its GGY repeats.

Amino Acid Sequence↗
PubMed2002

Clinical, electrophysiological, and serological overlap between Miller Fisher syndrome and acute sensory ataxic neuropathy.

We report a patient with severe sensory ataxia, areflexia, and ophthalmoplegia with preservation of limb muscle strength. Electrophysiological examinations revealed peripheral sensory nerve involvement. A serological examination showed the elevation of IgG antibodies to various b-series gangliosides as well as GT1a. These indicated that this case is an overlap between acute sensory ataxic neuropathy and Miller Fisher syndrome. Autoantibody is implicated as potential pathogenic agents in some cases of acute sensory ataxic neuropathy.

Acute Disease↗
PubMed2002

Conserved CDR 3 region of T cell receptor BV gene in lymphocytes from bronchoalveolar lavage fluid of patients with idiopathic pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is an inflammatory lung disease characterized by the accumulation of inflammatory cells and deposition of collagen, resulting in lung remodelling. High numbers of T cells are present in bronchoalveolar lavage fluid (BALF) of IPF patients, although the characteristics of these cells are yet to be determined. To elucidate the pathogenic mechanisms of IPF, we analysed the T cell receptor (TCR) of BALF lymphocytes in three patients with IPF and three healthy subjects as control. TCR repertoire of BALF lymphocytes and T cell clonality were examined by family PCR and Southern blot analysis, and single-strand conformation polymorphism (SSCP), respectively. We observed that the TCR repertoire in the lung was heterogeneous, both in the control subjects and three patients with IPF. SSCP analysis demonstrated an increase in the number of accumulated T cell clones in BALF of two of the three patients, but not in the healthy subject. Furthermore, junctional sequence analysis showed the presence of conserved amino acid motifs (ETGRSG, LAxG, QGQ, GxQP, GRxG, VAR, PGT, GTI, GGT, TGR, LxLxQ, SGQ) in the TCR-CDR 3 region of BAL lymphocytes in patients with IPF, whereas only two amino acid motifs (VTTG, GGE) were found in the control. Our findings suggest that T cells in BALF of patients with IPF expand oligoclonally in the lung, suggesting antigen stimulation of these cells.

Adult↗
PubMed2002

Characteristics of immunity induced by viral antigen or conferred by antibody via different administration routes.

The characteristics of the immunity induced by viral antigens or conferred by antiviral antibody via different routes of administration were evaluated comparatively. C57BL/6 mice were immunized via intranasal, intradermal or enteric routes with a live recombinant vaccinia virus expressing the respiratory syncytial virus (RSV) F glycoprotein (F.rVV) or RSV, and then challenged intranasally with RSV. Inhibition of RSV replication was observed in the lungs of all the mice; however, only intranasal immunization hindered virus replication in the nose. Lung inflammation, characterized by infiltration of neutrophils and of mononuclear cells was strongest in the intradermally immunized mice, but was observed in all F.rVV immunized mice to various degrees. Intranasal administration of a potently neutralizing human anti-RSV antibody Fab fragment to infected mice inhibited RSV replication in the nose and, when combined with intraperitoneal administration, protected both the lung and the nose in the absence of deleterious lung pathology. These data suggest that intranasal immunization with F.rVV reduces RSV replication in the respiratory tract, but still induces pathological lung inflammation, even though this is milder than that observed following intradermal immunization. Local neutralizing antibody is indispensable for protection in the nose.

Administration, Cutaneous↗
PubMed2002

Combinatorial peptide library for the analysis of antigen recognition by T cells.

Peptides that consist of 19 residues with random sequences (X19) were considered to deliver antigenic stimuli to CD4T cells. When IL-4, IL-7, IL-9, IL-15 and agonistic Ab to CD29 were co-cultured with single peripheral CD4T cells in the presence of X19 and feeder cells, T cells exhibited clonal expansion. These T cell clones showed heterogeneous proliferation patterns against KGXXXXXXXXXGK-based and KGXXXXXXXXXGKGKK-based combinatorial peptide libraries. Pattern-match search on one of the T cell clones resulted in peptide ligand candidates, one of which induced proliferation, as did protein molecules carrying the corresponding sequence. Combinatorial chemistry was useful in determining not only peptide ligands but also peptide superagonists. For this purpose, use of reverse-phase hydrophobic interaction chromatography and mass spectrometry analysis was efficient. Detailed methods are described in the paper.

Amino Acid Sequence↗
PubMed2001

Blepharismins, produced by the protozoan, Blepharisma japonicum, form ion-permeable channels in planar lipid bilayer membranes.

Blepharismins are polycyclic quinones found in the pigment granules of the ciliated protozoan, Blepharisma. Exposure to purified blepharismins results in lethal damage to several other ciliates. We here report that, at cytotoxic concentrations, blepharismins formed cation-selective channels in planar phospholipid bilayer membranes. The channels formed in a diphytanoylphosphatidylcholine bilayer had a K(+)/Cl(-) permeability ratio of 6.6:1. Single channel recordings revealed the conductance to be quite heterogeneous, ranging from 0.2 to 2.8 nS in solutions containing 0.1 M KCl, possibly reflecting different states of aggregation of blepharismin. Our observations suggest that channel formation is a cytotoxic mechanism of blepharismin's action against predatory protozoa.

Animals↗
PubMed2001

Major roles of prostanoid receptors IP and EP(3) in endotoxin-induced enhancement of pain perception.

To know the roles of prostaglandin I (IP) and prostaglandin E (EP) receptors in pain perception, we compared the acetic acid-induced writhing response in mice deficient in prostaglandin receptors, i.e. IP, EP(1,) EP(2,) EP(3,) or EP(4,) with or without lipopolysaccharide (LPS) pretreatment. Without LPS pretreatment, IP-receptor deficient mice showed a significantly smaller number of responses, as previously reported, whereas mice deficient in any of the EP-receptor subtypes showed a number of writhings similar to those of wild-type mice. When mice were pretreated with LPS for 24 hr to induce cyclooxygenase-2 expression, the wild-type as well as EP(1)-, EP(2)-, or EP(4)-receptor-deficient mice showed a similar enhanced writhing response, whereas IP- and EP(3)-receptor-deficient mice had a significantly less enhanced number of writhings. These results indicate that IP and EP(3) are the major prostaglandin receptors mediating the enhanced acetic acid-induced writhing response in mice pre-exposed to LPS, i.e. in endotoxin-enhanced inflammatory nociception.

Animals↗
PubMed2001

Subtotal corpectomy versus laminoplasty for multilevel cervical spondylotic myelopathy: a long-term follow-up study over 10 years.

STUDY DESIGN: A retrospective study was conducted. OBJECTIVE: To compare the long-term outcomes of subtotal corpectomy and laminoplasty for multilevel cervical spondylotic myelopathy. SUMMARY OF BACKGROUND DATA: No study has compared the long-term outcomes between subtotal corpectomy and laminoplasty for multilevel cervical spondylotic myelopathy. METHODS: In this study, 23 patients treated with subtotal corpectomy and 24 patients treated with laminoplasty were followed up for 10 to 14 years after surgery. Neurologic recovery, late deterioration, axial pain, radiographic results (degenerative changes at adjacent levels, alignment, and range of motion of the cervical spine), and surgical complications were compared between the two groups. RESULTS: No significant difference in neurologic recovery was found between the two groups 1 and 5 years after surgery, or at the latest follow-up assessment. Neurologic status deteriorated in one patient of the subtotal corpectomy group because of adjacent degeneration, and in one patient of the laminoplasty group because of hyperextension injury. Axial pain was observed in 15% of the corpectomy group and in 40% of the laminoplasty group (P < 0.05). In the corpectomy group, listhesis exceeding 2 mm developed at 38% of the upper adjacent levels, and osteophyte formation at 54% of the lower adjacent levels. In the laminoplasty group, kyphotic deformity developed in one patient (6%) after surgery. In the corpectomy group, the mean vertebral range of motion had decreased from 39.4 degrees to 19.2 degrees (49%) by the final follow-up assessment. In the laminoplasty group, the mean vertebral range of motion had decreased from 40.2 degrees to 11.6 degrees (29%) by the final follow-up assessment. Neurologic complications related to the surgery occurred in two patients (one myelopathy from bone graft dislodgement and one C5 root palsy from bone graft fracture) of the corpectomy group and four patients (C5 root palsy) of the laminoplasty group. All of these patients recovered over time. The corpectomy group needed longer operative time (P < 0.001) and tended to have more blood loss (P = 0.24). Six patients in the corpectomy group needed posterior interspinous wiring because of pseudarthrosis. CONCLUSIONS: Subtotal corpectomy and laminoplasty showed an identical effect from a surgical treatment for multilevel cervical spondylotic myelopathy. These neurologic recoveries usually last more than 10 years. In the subtotal corpectomy group, the disadvantages were longer surgical time, more blood loss, and pseudarthrosis. In the laminoplasty group, axial pain occurred frequently, and the range of motion was reduced severely.

Aged↗
PubMed2001

Photosensory transduction in unicellular eukaryote Blepharisma.

In the ciliated protozoan Blepharisma, step-up photophobic response is mediated by a novel type of photosensory complex of pink-colored pigment "blepharismins" and 200-kDa membrane protein contained in the pigment granules located just beneath the plasma membrane. We found that the fluorescence intensity of isolated blepharismins decreased prominently with a decrease of H(+) concentration in the surrounding medium. In the present study, therefore, we utilized the endogenous pigment blepharismins as the pH indicator. Light stimulation evoked a sudden decrease in fluorescence intensity in a photosensitive anterior portion of the cell, suggesting that a drop in H(+) concentration occurred in the anterior region. The result indicates that the photosignal is transduced into cytoplasmic signaling of H(+) translocation across the outer membrane surrounding the pigment granules, so that cytosolic H(+) concentration in the vicinity of plasma membrane might be increased.

Animals↗
PubMed2001

The DNA binding activity of the RIPE3b1 transcription factor of insulin appears to be influenced by tyrosine phosphorylation.

The RIPE3b1 DNA binding factor plays a critical role in pancreatic islet beta cell-specific and glucose-regulated transcription of the insulin gene. Recently it was shown that RIPE3b1 binding activity in beta cell nuclear extracts is reduced by treatment with either calf intestinal alkaline phosphatase (CIAP) or a brain-enriched phosphatase preparation (BPP) (Zhao, L., Cissell, M. A., Henderson, E., Colbran, R., and Stein, R. (2000) J. Biol. Chem. 275, 10532-10537). Evidence is presented here suggesting that a tyrosine phosphatase(s) influences the ability of RIPE3b1 to bind to the insulin C1 element in beta cells. We found that RIPE3b1 binding was inhibited upon incubating beta cell nuclear extracts at 30 degrees C. In contrast, PDX-1 and MLTF-1 transcription factor binding activity was unaffected under these conditions. The loss in RIPE3b1 binding activity was prevented by inhibitors of tyrosine phosphatases (sodium orthovanadate and sodium molybdate) but not by inhibitors of serine/threonine phosphatases (sodium fluoride, okadaic acid, and microcystin LR). CIAP- and BPP-catalyzed inhibition of RIPE3b1 binding was also blocked by these tyrosine phosphatase inhibitors. Collectively, the data suggested that removal of a tyrosine(s) within RIPE3b1 prevented activator binding to insulin C1 control element sequences. The presence of a key phosphorylated tyrosine(s) within this transcription factor was further supported by the ability of the 4G10 anti-phosphotyrosine monoclonal antibody to immunoprecipitate RIPE3b1 DNA binding activity. We discuss how tyrosine phosphorylation, a very rare and highly significant regulatory modification, may control RIPE3b1 activator function.

Base Sequence↗
PubMed2001

New therapy complementary to transcatheter arterial embolization for hepatocellular carcinoma.

A new therapy complementary to transcatheter arterial embolization (TAE) in which anticancer agents are percutaneously injected into the tumor under ultrasound guidance (percutaneous injection chemotherapy combined with TAE; TAE-PICT) has been developed and found to be effective. A total of 68 hepatocellular carcinoma (HCC) nodules in 50 patients were treated with TAE-PICT, and the complications were evaluated. Among those with solitary HCC nodules < or = 5 cm in diameter, 17 were treated with TAE-PICT and 24 with only TAE in a prospective comparative study. No major complications were seen, and the anticancer drugs could still be found in the tumor 3 months after injection. A significantly higher cumulative survival rate (p= 0.03961) and significantly higher cumulative recurrence-free survival rate (p = 0.00647) were achieved in patients treated with TAE-PICT than in those treated with TAE alone.

Aged↗
PubMed2001

Monocytes are differentially activated through HLA-DR, -DQ, and -DP molecules via mitogen-activated protein kinases.

When HLA-DR, -DQ, and -DP were cross-linked by solid-phase mAbs, monocytes produced monokines and only anti-DR markedly activated mitogen-activated protein (MAP) kinase extracellular signal-related kinase, whereas anti-DR, anti-DQ, and anti-DP all activated MAP kinase p38. Activation of extracellular signal-related kinase was not inhibited by neutralizing Ab to TNF-alpha. Anti-DR and DR-restricted T cells stimulated monocytes to produce relatively higher levels of proinflammatory monokines, such as IL-1beta, whereas anti-DQ/DP and DQ-/DP-restricted T cells stimulated higher levels of anti-inflammatory monokine IL-10. IL-10 production was abrogated by the p38 inhibitor SB203580, but rather enhanced by the MAP/extracellular signal-related kinase kinase-I-specific inhibitor PD98059, whereas IL-1beta was only partially abrogated by SB203580 and PD98059. Furthermore, DR-restricted T cells established from PBMC, which are reactive with mite Ags, purified protein derivative, and random 19-mer peptides, exhibited a higher IFN-gamma:IL-4 ratio than did DQ- or DP-restricted T cells. These results indicate that HLA-DR, -DQ, and -DP molecules transmit distinct signals to monocytes via MAP kinases and lead to distinct monokine activation patterns, which may affect T cell responses in vivo. Thus, the need for generation of a multigene family of class II MHC seems apparent.

Adult↗