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T Matsubayashi

Publications and source records attributed to T Matsubayashi.

At least 19 recordsLinked to original sources
PubMed2000

Different amounts of K-ras mutant epithelial cells in pancreatic carcinoma and mass-forming pancreatitis.

Clinically, differential diagnosis of pancreatic carcinoma (PC) and so-called "mass-forming pancreatitis (MFP)" is difficult. We analyzed the amount, ductal level, and K-ras mutation of ductal hyperplasia and intraductal carcinoma in surgically resected cases of MFP (n = 18) and PC (n = 16). DNAs extracted from microdissected epithelial foci were analyzed for K-ras codon 12 mutation by nested polymerase chain reaction and restriction fragment length polymorphism. The histology of MFP showed severe destruction of exocrine tissue and pancreatic stones and/or protein plugs (72%, 13 of 18 cases) in mostly peripheral ducts. The average basal membrane lengths of nonpapillary and papillary hyperplasia in cases of carcinoma were about 4 and 15 times more than those of MFP, respectively. The frequency of K-ras mutation in hyperplastic foci increased from nonpapillary [six (27%) of 22] to papillary foci [16 (64%) of 25] in K-ras mutant PCs, but there was no difference between nonpapillary [one (6%) of 18] and papillary foci (none of 19) in K-ras wild-type PCs, and also between nonpapillary (none of 24) and papillary foci [one (7%) of 14] in MFPs.

Adenocarcinoma↗
PubMed2000

Murine Delta homologue, mDelta1, expressed on feeder cells controls cellular differentiation.

The Delta/Serrate-Notch pathway is involved in intercellular signaling that controls cell fate during the development of invertebrates and vertebrates. Delta is a prototype of Notch ligands and has been studied extensively in Drosophila. In higher vertebrates, four Delta/Serrate homologues and four Notch homologues have been identified. Recent studies showed that the murine Delta homologue, mDelta1, is essential in early embryogenesis. The biological activity of mammalian Delta and its roles in cellular differentiation, however, have remained unclear. In this study, we first surveyed expression of mDelta1 in the adult mouse and found it to be present in a wide range of tissues. For testing biological activity of mDelta1, we expressed a mDelta1 full-length cDNA in L cells using a eukaryotic expression vector. Effects of mDelta1 on cellular differentiation were examined in two independent systems, featuring C2C12 myogenic differentiation and multipotent murine bone marrow cell differentiation. Inhibition of the former was observed with mDelta1 expression on L cells, associated with suppression of myogenin, a myogenic transcription factor. Expression of mDelta1 in conjunction with GM-CSF promoted differentiation of bone marrow cells to myeloid dendritic cells at the expense of other lineages. Although the effects of mDelta1 on two differentiation systems appeared opposing, as inhibition occurring in one and induction in the other, this can be understood by the unifying concept of generation of diverse cell types from equivalent progenitors. Thus, the present study provided evidence that mammalian Delta participates in intercellular signaling, determining the cell fate in a wide variety of tissues.

Animals↗
PubMed2000

Bone marrow changes mimicking myelodysplasia in patients with hemophagocytic lymphohistiocytosis.

In hemophagocytic lymphohistiocytosis (HLH), cytokine-induced pancytopenia is a common finding and is associated with hypoplastic and hypocellular bone marrow and abundant hemophagocytosis. To date, neutrophil nuclear segmentation abnormalities have not been clarified in HLH patients. We report a study of bone marrow from 6 cases of HLH that showed abnormal granulocytes, dyserythropoietic changes, and micromegakaryocytes mimicking the findings in myelodysplasia at the onset of disease. Pelger-Huët anomalies were particularly noted in all cases. The increased levels of cytokines in these cases may have caused cellular damage leading to the morphological changes in the bone marrow of these HLH patients. The impact of these findings on pathophysiology and prognosis in HLH patients remains to be determined.

Adolescent↗
PubMed1999

On the mechanism of the enhancement of delayed rectifier K+ current by extracellular ATP in guinea-pig ventricular myocytes.

The effects of extracellular adenosine 5'-triphosphate (ATP) on the delayed rectifier K+ current (IK) were studied in guinea-pig ventricular myocytes using the whole-cell voltage-clamp technique. ATP increased IK concentration dependently with a concentration eliciting a half-maximal response of 1.86 microM and a maximal increase of about 1.8-fold. The enhancement of IK developed slowly, the effect reaching a maximum in about 1.6 min after application of ATP. The rank order of agonist potency in enhancing IK was 2-methylthio-ATP>/= ATP>>alpha,beta-methylene-ATP. The ATP response was attenuated in guanosine 5'-O-(2-thiodiphosphate) (GDPbetaS)- loaded cells, but was not affected by pertussis toxin (PTX)-pre-treatment, indicating that a PTX-insensitive G protein is involved in the response. These features are consistent with operation of P2Y-type purinoceptors. ATP produced a further increase in IK stimulated maximally either by isoprenaline (1 microM) through protein kinase A (PKA) or by 12-O-tetradecanoylphorbol 13-acetate (TPA, 100 nM) through protein kinase C (PKC), while 1-(5-isoquinolinesulfonyl)-2-methylpiperazine dihydrochloride (H-7, 10 microM) did not affect the ATP response, suggesting that PKA and PKC do not mediate the response. ATP irreversibly enhanced IK in cells loaded with adenosine 5'-O-(3-thiotriphosphate) (ATPgammaS, 5 mM) or okadaic acid (10 microM), a phosphatase inhibitor, suggesting that a phosphorylation step is present after the receptor stimulation. Genistein, an inhibitor of tyrosine phosphorylation, suppressed the ATP response significantly, while daidzein, an inactive analogue of genistein, had little effect on it, although both genistein or daidzein alone decreased IK. It is hypothesized that tyrosine phosphorylation plays a role in the signalling pathway involved in the enhancement of cardiac IK by P2Y-purinergic stimulation.

Adenosine Triphosphate↗
PubMed1999

[CT findings of nasal non-Hodgkin's lymphomas associated with prognosis].

X-ray CT images of the head obtained from thirteen patients (9 men and 4 women) among 33 patients (19 men and 14 women) with nasal non-Hodgkin's lymphoma (NHL) who had been seen at Kitasato University Hospital during the period from April 1975 to March 1995 were retrospectively reviewed to search for useful prognostic image factors for nasal NHL. Extracavitary subcutaneous tumor extension into the nasal wing or cheek, and tumor penetration through the nasal septum revealed on X-ray CT images seemed to be likely indicators of a poor prognosis for patients with nasal NHL.

Female↗
PubMed1999

[Progress in interventional radiology (IVR) in emergency medicine].

IVR has attracted much attention in Japan over the past decade, and it is expected to be rapidly developed and widely used. Not surprisingly, IVR has already become essential in emergency medicine. This paper addresses IVR of the thoracic and abdominal areas and the pelvis in emergency medicine, in particular the recent IVR focus on the vasculature. CO2-DSA, which enables extravasation and easy detection of a arteriovenous or portal shunt, is also useful in the detection of bleeding in emergency situations. In trauma cases, TAE, originating from an expanded concept of "damage control," is commonly used to stop bleeding in order to perform surgical treatment or used during surgery. Occasionally the two applications are combined when appropriate. TAE is effective in controlling retroperitoneal bleeding resulting from pelvic fracture and parenchymatous organ injuries in the abdominal area. Treatment with stent-grafts, originally used to treat true aneurysms, has recently been used for treatment of injuries of the aorta or arteries and for entry closure due to aortic dissection. Furthermore, stent placement is expected to become an effective cure for organ ischemia, resulting from acute dissections. Is addition, in order to cure rupture of esophagus or gastric varices, such new treatments as TIPS and BRTO have increasingly been used, coupled with the conventional PTO treatment. Continuous regional arterial infusion of protease inhibitor, in an attempt to cure severe acute pancreatitis, significantly reduced the infectious rate at the necrotic lesion, and its resulting mortality rate. It is certain that great progress has been made in emergency medicine. We also should realize that it is desirable to be well versed even in new IVR.

Emergency Medical Services↗
PubMed1998

Intracellular Mg2+ depletion depresses the delayed rectifier K+ current in guinea pig ventricular myocytes.

The effects of various [Mg2+]i, particularly low [Mg2+]i, on the delayed rectifier K+ current (IK) were studied in guinea pig ventricular myocytes with the patch clamp technique. The magnitude of IK was evaluated from the amplitude of its tail current elicited on repolarization following the depolarizing steps. The pipette-perfusion technique was also used. The initial variations of IK magnitude were dependent on [Mg2+]i in the internal solutions with which the whole-cell recording was begun. With 0.03 to 1 mM [Mg2+]i, IK was relatively stable after patch rupture, showing a minimal decay with time; with 3 mM [Mg2+]i, IK rapidly declined; with [Mg2+]i, less than 0.01 mM IK transiently increased after patch break, but declined progressively thereafter as the magnitude of IK decreased to about 30% of the initial magnitude in 10 min. The decline of IK at low [Mg2+]i showed the following features. The decline was accompanied little by changes in the voltage-activation relation or by changes in the kinetics of current deactivation. The decline was not related to changes in [Ca2+]i and was also observed in ATP gamma S-loaded, isoprenaline-stimulated cells, in which IK channels were presumed to be persistently phosphorylated. An application of okadaic acid did not prevent the decline of IK during Mg2+ depletion. It is suggested that a presence of [Mg2+]i higher than 0.01 mM is required to maintain IK in guinea pig ventricular cells. The depression of IK at low [Mg2+]i appears to involve a phosphorylation-dephosphorylation-independent mechanism.

Adenosine Triphosphate↗
PubMed1998

Basic and clinical studies on ApoE gene typing by line probe assay (LiPA) as a biological marker for Alzheimer's disease and related disorders: multicenter study in Japan.

The fundamental reagent capability and clinical significance of ApoE gene typing has been investigated. The result of each test shows that the reagent capability satisfied the expected standard. Four-hundred thirty-nine samples classified into three groups (Alzheimer's disease (AD), other types of dementia and nondementia) were measured to examine the clinical significance. The rate of epsilon 4 genotype of each group was 31.5%, 14.6%, 10.4%, respectively. The AD group had a higher rate than the other groups (p < 0.001). The measurement of ApoE genotype is suggested to be useful as one of the guidelines in the diagnosis of AD.

Age Factors↗
PubMed1998

Basic and clinical studies on the measurement of tau protein in cerebrospinal fluid as a biological marker for Alzheimer's disease and related disorders: multicenter study in Japan.

The development of a diagnostic marker for earlier and more accurate clinical diagnosis of Alzheimer's disease (AD) is essential to identify AD patients during life unequivocally. The purpose of this study was to investigate the basic performance and clinical significance of tau level measurement in the cerebrospinal fluid (CSF) using an enzyme-linked immunosorbent assay (ELISA) developed by Innogenetics. The ELISA system showed reliable reproducibility and good linearity. For clinical studies, the CSF samples from a variety of patients (n = 332) were examined. They were classified into the four groups: Alzheimer's disease (AD); neurodegenerative disease (ND); cerebrovascular diseases (VD); and a neurological control (NC) group. The CSF-tau levels for AD, ND, VD and NC were 426 +/- 234 pg/ml, 239 +/- 157 pg/ml, 216 +/- 136 pg/ml, and 188 +/- 103 pg/ml, respectively. The CSF-tau level of the AD group was significantly higher than that of the other groups (p < 0.001). The CSF-tau levels increased during follow-up. The measurement of the tau level in CSF is shown to be a useful marker to confirm a clinical diagnosis of AD.

Aged↗
PubMed1995

Genes encoding the group I intron-containing tRNA(Leu) and subunit L of NADH dehydrogenase from the cyanobacterium Synechococcus PCC 6301.

A part of the tRNA(Leu)(UAA) gene containing a 240-nucleotide group I intron was amplified by PCR from cyanobacterium Synechococcus PCC 6301 genomic DNA. The pre-tRNA synthesized from the cloned PCR product was efficiently self-spliced in vitro under physiological conditions. The gene encoding the tRNA(Leu)(UAA), trnL-UAA, was isolated from a Synechococcus PCC 6301 genomic library and the nucleotide sequence of a 2,167-bp portion was determined. The trnL-UAA consists of a 34-bp 5' exon, a 240-bp group I intron and a 50-bp 3' exon. In addition, three open reading frames (ORF1, ORF2 and ORF3) were found in the 5' and 3' flanking regions of trnL-UAA. The predicted protein sequence of ORF3, which is located 74-bp upstream from trnL-UAA on the opposite strand, shows 66.2% amino acid identity to that of the Synechocystis PCC 6803 gene encoding subunit L of NADH dehydrogenase (ndhL).

Amino Acid Sequence↗
PubMed1995

Detection of donor lymphocytes in the cerebrospinal fluid of a patient with metachromatic leukodystrophy following bone marrow transplantation.

An unrelated donor bone marrow transplant (UD-BMT) was carried out on a 10-year-old patient with metachromatic leukodystrophy (MLD). We collected cerebrospinal fluid (CSF) on day +168 and cultured it with recombinant IL-2 and PHA-P to examine the origin of cells in the CSF. Analysis on variable number of tandem repeat (VNTR) of lymphocytes in the CSF amplified by PCR revealed that lymphocytes in the CSF were of donor origin. These data support that BMT at an early stage may prevent deterioration in MLD. Although the patient developed grade III acute GVHD with rash and diarrhea, we successfully treated acute GVHD using rabbit anti-human thymocyte immunoglobulin (ATG). UD-BMT may be an alternative treatment for patients with MLD in the absence of an HLA matched family donor.

Bone Marrow Transplantation↗
PubMed1994

A physical map of the genome of a unicellular cyanobacterium Synechocystis sp. strain PCC6803.

An accurate physical map of the genome of a cyanobacterium, Synechocystis sp. strain PCC6803, was constructed on the basis of restriction and linking clone analysis. The genome contained 6 recognition sites for AscI, 25 sites for MluI, and 31 sites for SplI, and the entire genome size was estimated to be 3.6 Mb. Sixteen genes or gene clusters, including those involved in the photosynthetic systems, were localized on the physical map of the genome by hybridization. In the course of the above analysis, two extra chromosomal units with approximate sizes of 110 kb and 125 kb were identified.

Chromosome Mapping↗
PubMed1994

[False positives and false negatives seen in anti-HIV-1 antibody tests].

From September 1986 to December 1993 31059 anti-HIV antibody tests were performed on the samples from our clinic, from 29 health centers and their branches of Osaka Prefecture, from a hospital and from high risk groups. Enzyme immune assay (EIA) was used up to 1988 and from 1989 particle agglutination (PA) has been employed. The indeterminates of Western blot (WB) were seen in 5 EIA positives and in 2 PA positives. False positive rate of EIA was 0.235% (11/467) and that of PA was 0.011% (2/17922). Two false negative cases of anti-HIV-1 antibody test due to window period were documented and the importance of co-use of antigen test at the time of confirmative antibody tests was discussed.

Agglutination Tests↗