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T Taniguchi

Publications and source records attributed to T Taniguchi.

At least 757 records · Page 42Linked to original sources
PubMed1987

[Clinical experience with a Terumo guide wire in the urinary tract].

TERUMO guide wire was used for treatment of urinary tract diseases in 30 cases of percutaneous nephrolithotomy, 35 cases of transurethral retrieval for ureteral stones and one case each of stricture of uretero-ileal junction with a ureteral stone, urethral stricture after mechanical instrumentation, and cystic dilatation of terminal seminal duct with hematospermia. The advantages of the use of TERUMO guide wire in the urinary tract are described. The rigid stem wire with a floppy terminal portion is superior to other types of guide wires concerning flexibility, elasticity, degree of sliding and maneuverability.

Adult↗
PubMed1987

[Prognostic factors in nonresected adenocarcinoma of the lung].

We have studied the prognostic factors of 117 cases of unresected adenocarcinoma of the lung, and have examined these cases according to the following categories: age, sex, clinical stage, performance status (P.S.), serum albumin on admission, serum CEA, the presence of complication, the present status of an abnormal chest shadow from a year ago at the same location, and differentiation of cells. Significant differences were detected in the P.S., the serum albumin and the presence of complications by survival analysis through the use of covariate-Cox models. We also have noted that the difference between stage I and the other stages of the clinical stage was found to be significant by a generalized Wilcoxon test. In conclusion, the determining prognostic factors of an unresected adenocarcinoma of the lung are the P.S., the serum albumin, the presence of complications and the clinical stage.

Adenocarcinoma↗
PubMed1986

Enzymatic quantification of strand breaks of DNA induced by vacuum-UV radiation.

HindIII-digested plasmid DNA dried on an aluminum plate was irradiated by vacuum-UV at 160 and 195 nm using a synchrotron irradiation system. A change induced in the DNA, presumably a single strand break, was quantified by the aid of the strand break-derived stimulation of poly(ADP-ribose) synthetase activity. The end group of strand breaks so induced was recognized by the enzyme as effectively as that by DNase I treatment, suggesting a nicking as the major lesion inflicted on the DNA. The fluence (UV) dependent stimulation of poly(ADP-ribose) synthetase activity was much higher upon 160 nm irradiation than upon 195 nm irradiation.

DNA↗
PubMed1986

Regulation of human interleukin-2 gene: functional DNA sequences in the 5' flanking region for the gene expression in activated T lymphocytes.

Interleukin-2 (IL-2) is a lymphokine that plays a crucial role in the immune system, especially in the growth control of T lymphocytes. Expression of this lymphokine is restricted to activated T lymphocytes. Here we demonstrate the presence of unique DNA sequences in the 5' flanking region of the human IL-2 gene that control induced T-cell-specific gene expression. We also show that the DNA sequences function in an orientation-independent manner and activate a heterologous promoter which is otherwise inert in induced T cells. The DNA, which spans about 200 bp, contains regions with sequence homology to LTR sequences of HTLV-III (or LAV) and the 5' upstream region of the IL-2 receptor and interferon-gamma genes.

Base Sequence↗
PubMed1986

The structures of the asparagine-linked sugar chains of bovine interphotoreceptor retinol-binding protein. Occurrence of fucosylated hybrid-type oligosaccharides.

The sugar chains of interphotoreceptor retinol-binding protein purified from the interphotoreceptor matrix of bovine eyes were liberated from the polypeptide portion by hydrazinolysis followed by N-acetylation and NaB[3H]4 reduction. The oligosaccharide fraction thus obtained was separated into four acidic fractions by paper electrophoresis. The four acidic fractions were confirmed to be mixtures of mono-, di-, tri-, and tetrasialyloligosaccharides. Both N-acetyl- and N-glycolylneuraminic acids were found as sialic acids of interphotoreceptor retinol-binding protein. The monosialylated oligosaccharide fraction, which accounted for 40 molar per cent of the total oligosaccharides liberated, was a mixture of the following hybrid-type oligosaccharides: (Formula: see text) This is the first time that fucosylated hybrid-type oligosaccharides have been found in any glycoprotein. The di-, tri-, and tetrasialyloligosaccharide fractions were composed of biantennary complex-type oligosaccharides, the outer chains of which are either Sia alpha 2----(3- or 6-linked)Gal beta 1----3(Sia alpha 2----6)GlcNac or Sia alpha 2----(3- or 6-linked)Gal beta 1----4GlcNAc.

Animals↗
PubMed1986

Induction of interleukin 2 receptor gene expression by p40x encoded by human T-cell leukemia virus type 1.

Human T-cell leukemia virus type 1 (HTLV-1) is an etiologic agent of adult T-cell leukemia (ATL). A viral product, p40x, encoded by the pX sequence of HTLV-1 is a trans-acting transcriptional activator of the long terminal repeat (LTR) and has been suspected of involvement in leukemogenesis, activating the cellular genes. The cellular interleukin-2 (IL-2) and its receptor (IL-2R), the latter of which is expressed on ATL leukemic cells, were shown to be transiently induced by transfection of plasmid pMTPX expressing pX in two T-cell lines, Jurkat and HSB-2, but not in other human T- or B-cell lines. The cell type specificity of IL-2R induction by pX expression was the same as that by phytohaemagglutinin/phorbol ester activation, indicating the requirement for some specific cellular factors or a certain state of cellular differentiation. Induction of IL-2 and IL-2R at mRNA level was also demonstrated in transfected cells. Transfections with mutants of pMTPX in which the open reading frames for p40x, p27x-III and p21x-III were inactivated indicated that p40x alone was sufficient for induction of the IL-2R in inducible cells. This induction of the IL-2R by p40x of HTLV-1 may contribute to preferential proliferation of HTLV-1 infected cells at an early stage of ATL development and eventually increase the number of putative target cells for malignant transformation.

Cell Line↗
PubMed1986

Light and scanning electron microscopic observations on the two contrasting types of sister chromatid differential staining after ultraviolet light irradiation.

Chinese hamster cells were grown with 50 microM 5-bromodeoxyuridine (BrdU) during the penultimate S phase to obtain chromosomes with the TB-TT chromatid constitution. Chromosome preparations made by the airdrying method were used to study the sister chromatid differential staining (SCD) resulting from ultraviolet (UV) irradiation followed by Giemsa staining by light and scanning electron microscopy (SEM). When chromosomes irradiated with UV light (253.7 nm, 5.2 J/m2/s) for more than 5 h were stained with 1% to 4% Giemsa in phosphate buffered saline (PBS) or in distilled water, the resulting SCD invariably belonged to the B-light type in which the TB-chromatid stained lightly. SEM observations of these chromosomes suggested that the B-light SCD was due to the selective photolysis of the TB-chromatid. On the other hand, when chromosomes were irradiated for only 10 min, and stained with 1% Giemsa in PBS, they showed a B-dark type SCD in which the TB-chromatid stained darkly. However, when chromosomes irradiated for 10 min were stained with 4% Giemsa in PBS or 1% Giemsa in distilled water, the resulting SCD again belonged to the B-light type. These findings indicate that when the irradiation dose is small, the resultant SCD is not a simple reflection of selective photolysis in the TB-chromatids and the type of SCD depends not only on the concentration of Giemsa but also on the salinity of the staining solution.

Animals↗
PubMed1986

High-order structure of metaphase chromosomes: evidence for a multiple coiling model.

When chromosome preparations made by the conventional air-drying method were processed with the OSO4/TCH technique and examined by scanning electron microscopy (SEM), spiral structures in chromatids, which have been frequently observed to be present by light microscopy, were found to be composed of 30 nm fibres. In some portions these fibres appeared to be arranged in coils to form thicker fibres. When chromosome preparations were processed for SEM without air drying, chromosomes appeared to consist of fairly homogeneous thick fibrous structures measuring about 200 nm in diameter. In relatively condensed chromosomes, these 200 nm fibres appeared to be arranged perpendicular to the long axis of the chromatid. These findings suggest that chromatid spiral structures represent a regularly loosened state of the compactly spiralized 200 nm fibres which in turn consist of spiralized 30 nm fibres.

Animals↗
PubMed1986

Sympathetic denervation and alpha adrenoceptors in dog cerebral arteries.

The magnitude of the noradrenaline-induced contractions of dog middle cerebral arteries was less than that seen in the vertebral, common carotid, femoral and renal arteries. Noradrenaline and clonidine produced a similar magnitude of maximum contractions in the middle cerebral arteries, whereas methoxamine produced no significant contractions in the same arteries. In the extracranial arteries, noradrenaline and methoxamine produced significantly larger contractions than clonidine. Binding studies revealed no specific 3H-prazosin binding sites in the cerebral arteries, though such binding sites were evident in the case of extracranial arteries. 3H-Yohimbine binding studies revealed the presence of two classes of binding sites with high and low affinities in both cerebral and extracranial arteries. After superior cervical ganglionectomy, noradrenaline- and clonidine-induced contractions of the denervated middle cerebral arteries were not altered, compared with the control arteries. A 3H-yohimbine binding study was also performed using the denervated cerebral arteries. This study revealed that there was a low affinity 3H-yohimbine binding site, whereas high affinity 3H-yohimbine binding site was not detectable. These results suggest the presence of two different binding sites with high and low affinity for alpha 2 adrenoceptors, which we are classifying into alpha 2H and alpha 2L subtypes. The high affinity sites, alpha 2H adrenoceptors, are presynaptically located while the low affinity sites, alpha 2L adrenoceptors, located postsynaptically. The noradrenaline-induced contractions are probably mediated by postsynaptic low affinity sites of alpha 2 adrenoceptors (alpha 2L adrenoceptors) in the cerebral arteries and mainly by alpha 1 adrenoceptors in the extracranial arteries.

Animals↗
PubMed1986

Effects of methylnitrosourea on visualization of acridine orange binding to DNA in mouse lymphoma L-1210 cells.

The purpose of this study is to examine effects of methylnitrosourea (MNU) on electron microscopic visualization of acridine orange (AO) binding to DNA in mouse lymphoma L-1210 cells and to demonstrate alteration of the euchromatin/heterochromatin ratio by morphometry. [3H] uridine uptake into RNA molecule is inhibited and percentage of AO positive cells is decreased to approximately 20% of that of the untreated control cells by treatment of the lymphoma cells with MNU. When the MNU-treated cells are cultured in the presence of 3-amino-benzamide, a specific inhibitor of poly(ADP-ribose) synthetase, the depression in RNA synthesis is prevented, and percentage of AO positive cells as well as numbers of AO chromatin interaction products per single cell nucleus are also completely recovered as compared to those in the untreated cells. In the MNU-treated cells the decreased number of AO positive cells coincides with a reduced [3H] uridine uptake as well as with a lowered euchromatin/heterochromatin ratio. The results suggest that visualization of AO chromatin interaction products in the proliferating cells is related not only to RNA synthesis in the cells, but also to the euchromatin/heterochromatin ratio.

Acridine Orange↗
PubMed1986

Intracytoplasmic phosphorylation sites of Tac antigen (p55) are not essential for the conformation, function, and regulation of the human interleukin 2 receptor.

Tac antigen, the receptor for human interleukin 2 (IL-2), contains in its intracytoplasmic region a serine residue (Ser-247) that is seemingly the predominant site of protein kinase C-mediated phosphorylation. A number of studies on growth factor receptors have suggested the importance of phosphorylation in receptor structure, function, and regulation. In this study, we generated site-directed mutations in the Tac antigen cDNA to generate mutant receptors in which Ser-247 or Thr-250, a probable site of minor phosphorylation, was replaced with another amino acid that is not accessible to phosphorylation. Study of the expression of these mutant genes in a T-lymphoid cell line has provided no evidence as to the essential role of the above-mentioned residues in determining the degree of receptor affinity, its ability for signal transduction, and phorbol ester-mediated regulation of the receptor. Our results strongly suggest the existence of an IL-2 receptor "complex" in which the Tac antigen is associated with another molecule(s) that is involved in receptor structure, function, and regulation.

Amino Acid Sequence↗
PubMed1986

Changes in nicotinic and muscarinic cholinergic receptors in Alzheimer-type dementia.

Nicotinic and muscarinic cholinergic receptors were studied in autopsied brains from four histologically normal controls and five histopathologically verified cases of Alzheimer-type dementia (ATD), using ligand binding techniques. Nicotinic and muscarinic cholinergic receptors were assessed by (-)-[3H]nicotine and [3H]quinuclidinyl benzilate [( 3H]QNB), respectively. Compared with the controls, (-)-[3H]nicotine binding sites in the ATD brain regions examined were significantly reduced in the putamen and the nucleus basalis of Meynert (NbM). [3H]QNB binding was significantly reduced in the hippocampus and NbM. These findings suggest that there are significant changes of nicotinic and muscarinic cholinergic receptors in selected regions of ATD brains.

Aged↗