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Biomedical subjects

T Noguchi

Publications and source records attributed to T Noguchi.

At least 595 records · Page 33Linked to original sources
PubMed1991

Expression of liver type pyruvate kinase in insulinoma cells: involvement of LF-B1 (HNF1).

The messages for LF-B1, which interacts with the cis-acting element of PKL-I to play an essential role in expression of L-type pyruvate kinase (PK) in the liver, and L-type PK were found to be present in RIN-m5F insulinoma cells as well as the liver, kidney and small intestine, although the levels of the two mRNAs in these tissues were not correlated. Gel retardation assay suggested that similar nuclear proteins bound to two other cis-acting elements, PKL-II and PKL-III, were expressed in both liver and insulinoma cells, and that additional PKL-III-binding proteins were present only in RIN-m5F cells. Thus, we suggest that the mechanism of L-type PK expression in pancreatic B cells is similar to that in the liver.

Animals↗
PubMed1991

6-Deoxy-D-talan and 6-deoxy-L-talan. Novel serotype-specific polysaccharide antigens from Actinobacillus actinomycetemcomitans.

Serotype-specific polysaccharide antigens from Actinobacillus actinomycetemcomitans ATCC 29523 (serotype a) and NCTC 9710 (serotype c) were extracted from whole cells by autoclaving and purified by ion-exchange chromatography and gel filtration. Analysis of component sugars by gas-liquid chromatography-mass spectrometry, high performance liquid chromatography, and NMR together with optical rotation data showed that the serotype a antigen was composed solely of 6-deoxy-D-talose, whereas the serotype c antigen consisted of 6-deoxy-L-talose. Structural analysis indicated that both of these antigens were composed of closely related repeating units, -3)-6-deoxy-alpha-D-Talp-(1-2)-6-deoxy-alpha-D-Talp-(1-(sero type a) and -3)-6-deoxy-alpha-L-Talp-(1-2)-6-deoxy-alpha-L-Talp-(1-(sero type c). 1H and 13C NMR analysis showed that both of these serotype antigens contained one acetyl group/2 sugar residues. These acetyl groups localized at the O-2 position of 3-linked 6-deoxy-D-talose (serotype a) or O-4 position of 3-linked 6-deoxy-L-talose residues (serotype c), respectively. These results coupled with our previous findings on the serotype b antigen (Amano, K., Nishihara, T., Shibuya, N., Noguchi, T., and Koga, T. (1989) Infect. Immun. 57, 2942-2946) showed that the serotype antigens from A. actinomycetemcomitans are a group of novel polysaccharides with structural features closely related biosynthetically.

Actinobacillus↗
PubMed1991

An efficient method for constructing a chimeric bacteriophage T4 to estimate the regulatory signals.

A system for the quantitative estimation of T4 regulatory signals in bacteriophage T4 was developed. We constructed a transmitter-reporter [corrected] plasmid vector, pCV22, which is able not only to fuse transcriptional and translational signals to the coding region of lacZ gene (reporter) but also to transmit the fused gene into T4 phage genome (transmitter). The regulatory signals of T4 phage genes fused with the reporter gene was transmitted efficiently into T4 phage (T4dC-lac phage; a receiver phage) by a replacement type of recombination in the uvsY gene region. This type of chimeric phage was demonstrated to be able to quantitatively estimate the late regulatory signal of T4 phage in vivo.

Chimera↗
PubMed1991

Structure of the entire human muscle phosphofructokinase-encoding gene: a two-promoter system.

We have recently shown that three types (A,B, and C) of mRNA species are transcribed from a single gene encoding human muscle phosphofructokinase (hPFK-M) through alternative splicing [Nakajima et al., Biochem. Biophys. Res. Commun. 166 (1990) 637-641]. To determine its complete structure and elucidate the mechanism of alternative RNA splicing, we isolated the hPFK-M gene, which spans about 30 kb, and contains 24 exons. Transcription start points were observed for both exon 1 and exon 2 by S1 nuclease protection assay and primer extension. Motifs of an Sp1-binding site were observed in the upstream region of exon 1 (promoter 1). A TATA-box-like sequence and a CAAT-box-like sequence were identified in the upstream region of exon 2 (promoter 2). Reporter assay revealed that the promoter 1 region was functional both in HeLa cells and myoblastic clonal cells, and that the promoter 2 region was active only in myoblastic cells. Motifs of M-CAT known as a muscle-specific enhancer, were observed in the promoter 2 region. These results indicated that the hPFK-M gene contains at least two promoter regions, facilitating the expression of the heterogeneous gene transcripts in a cell-type-specific manner.

Base Sequence↗
PubMed1991

Induction of in vitro and in vivo anti-tumor responses by sensitization of mice with liposomes containing a crude butanol extract of leukemia cells and transferred inter-membranously with cell-surface proteins.

Generation of cytotoxic T lymphocytes (CTL) in vitro and tumor-rejection responses by sensitization of semi-syngeneic mice with tumor-antigen-reconstituted liposomes were investigated. Liposomes were prepared from a crude butanol extract (CBE) of BALBRVD leukemia cells and egg phosphatidylcholine (PC): 1,2-dimyristoylamido-1,2-deoxyphosphatidylcholine (DDPC) (3:2) or dimyristoylphosphatidylcholine (DMPC):DDPC (1:4). Inter-membrane protein transfer (IMPT) liposomes were prepared by incubating BALBRVD cells with DMPC:DDPC (1:4) liposomes. Sensitization of male CB6F1 mice with CBE or IMPT liposomes induced a level of cytotoxicity similar to that on sensitization with mitomycin-C(MMC)-treated BALBRVD against BALBRVD target cells after in vitro sensitization with the tumor cells. Sensitization with CBE alone resulted in only marginal cytotoxicity. The cytotoxic effector cells induced by either mode of sensitization were CD8+ T-cells whose recognition was Kd-restricted. No difference in specificity was observed with the different modes of sensitization. Two in vivo immunizations with CBE or with CBE liposomes at a dose of 25 micrograms of protein (equivalent to 2.5 x 10(7) cells) cause moderate inhibition of BALBRVD tumor growth in male CB6F1 mice and immunization with IMPT liposomes at a dose of 1 microgram of protein result in efficient protection.

1-Butanol↗
PubMed1991

Isolation and characterization of the human pyruvate kinase M gene.

Genomic clones containing the human pyruvate kinase M (PKM) gene, which encodes the M1-type and M2-type isozymes, were isolated and their exon sequences were determined. The gene is approximately 32 kb and consists of 12 exons and 11 introns. Exons 9 and 10 contain sequences specific to the M1 and M2 types, respectively, indicating that the human isozymes are produced from the same gene by alternative splicing as in the case of the rat gene. The exon-intron structure of the human PKM gene is identical to that of the rat gene, and the introns of both genes interrupt the exons at the same points. Introns 6 and 7 begin with GC dinucleotide instead of the consensus GT, but the other exon-intron boundaries are consistent with the GT-AG rule. The gene is transcribed from multiple start sites. The 5'-flanking region of the gene contains putative Sp1-binding sites, but no TATA box or CAAT box, and shows high sequence similarity to that of the rat M gene. Bacterial chloramphenicol acetyltransferase assay revealed that the upstream region between positions -493 and -51 contained a cis-acting element(s) that was essential for expression of the M gene in HeLa cells. Long stretches of conserved regions were found in the introns around the M1-specific and M2-specific exons, suggesting that these regions may be involved in the alternative splicing machinery.

Amino Acid Sequence↗
PubMed1991

Alteration in L-type pyruvate kinase gene expression is not associated with the LF-B1 mRNA level.

The relation of expression of the LF-B1 gene with the L-type pyruvate kinase (L-PK) mRNA level in rat liver and hepatoma cells was investigated. The L-PK mRNA level in rat liver changed after partial hepatectomy, during development and on intake of a high carbohydrate diet, while the level of LF-B1 mRNA remained unchanged or altered reciprocally. Dedifferentiated AH-130 cells, which did not express L-PK mRNA, expressed LF-B1 mRNA. These results suggest that transcription of the pyruvate kinase L gene is not simply regulated by the level of LF-B1 mRNA.

Animals↗
PubMed1991

Intraperoxisomal form of alanine:glyoxylate aminotransferase in the peroxisomes of bird kidney.

Alanine:glyoxylate aminotransferase has been reported to be present as the apo form in the peroxisomes and as the holo form in the mitochondria in chicken kidney. In contrast, the enzyme was found to be present as the holo form both in the peroxisomes and in the mitochondria in pigeon kidney, suggesting that birds are classified into two groups on the basis of intraperoxisomal form of kidney alanine:glyoxylate aminotransferase. In the kidney, the pigeon peroxisomal holo enzyme did not cross-react immunologically with the chicken peroxisomal apo enzyme.

Alanine Transaminase↗
PubMed1991

Priming for in vitro and in vivo anti-human T lymphotropic virus type 1 cellular immunity by virus-related protein reconstituted into liposome.

In vitro and in vivo anti-human T lymphotropic virus type 1 (HTLV-1) cellular immunity was examined by immunizing rats with a truncated hybrid protein (228 amino acids) of gag and env of HTLV-1 produced by Escherichia coli. Animals were immunized with the hybrid protein reconstituted into mannan-derivative-coated liposomes (gag-env-lipo). In vitro sensitization with a HTLV-1-positive cell line, TARS-1, of spleen cells obtained from these animals generated killer cells specific for syngeneic HTLV-1-positive cells. No killer activity was generated when spleen cells were obtained from animals immunized with the hybrid protein alone, the liposome alone, or the hybrid protein reconstituted into conventional liposomes with no polysaccharide coating. Killer cells were CD8+ CTL restricted to MHC class I. Analysis of CD8+ and CD4+ subsets in spleens showed the existence of primed CD8+ T cells in animals immunized with gag-env-lipo. Rats immunized with gag-env-lipo displayed accelerated rejection of TARS-1 but not of two other HTLV-1-negative tumor lines. Injection of carrageenan into animals strongly inhibited generation of killer cells, which indicates the necessity of macrophages for priming of CD8+ T cells with gag-env-lipo. Injection of carrageenan also cancelled in vivo immunity against HTLV-1+ cells induced with gag-env-lipo. These results, taken together, indicate that exogenous protein reconstituted into appropriate liposomes can effectively prime MHC class I restricted CD8+ T cells in vivo with macrophage dependency.

Animals↗
PubMed1991

Purification and characterization of peroxisomal apo and holo alanine:glyoxylate aminotransferase from bird liver.

Alanine:glyoxylate aminotransferase has been reported to be present as the apo enzyme in the peroxisomes and as the holo enzyme in the mitochondria in chick (white leghorn) embryonic liver. However, surprisingly, birds were found to be classified into two groups on the basis of intraperoxisomal forms of liver alanine:glyoxylate aminotransferase. In the peroxisomes, the enzyme was present as the holo form in group 1 (pigeon, sparrow, Java sparrow, Australian budgerigar, canary, goose, and duck), and as the apo form in group 2 (white leghorn, bantam, pheasant, and Japanese mannikin). In the mitochondria, the enzyme was present as the holo form in both groups. The peroxisomal holo enzyme was purified from pigeon liver, and the peroxisomal apo enzyme from chicken (white leghorn) liver. The pigeon holo enzyme was composed of two identical subunits with a molecular weight of about 45,000, whereas the chicken apo enzyme was a single peptide with the same molecular weight as the subunit of the pigeon enzyme. The peroxisomal holo enzyme of pigeon liver was not immunologically cross-reactive with the peroxisomal apo enzyme of chicken liver, the mitochondrial holo enzymes from pigeon and chicken liver, and mammalian alanine:glyoxylate aminotransferases 1 and 2. The mitochondrial holo enzymes from both pigeon and chicken liver had molecular weights of about 200,000 with four identical subunits and were cross-reactive with mammalian alanine:glyoxylate aminotransferase 2 but not with mammalian alanine:glyoxylate aminotransferase 1.

Alanine Transaminase↗
PubMed1991

Characterization of phosphopeptide derived from bovine beta-casein: an inhibitor to intra-intestinal precipitation of calcium phosphate.

Casein phosphopeptide (CPP), a highly phosphorylated peptide fragment which inhibits the formation of hydroxyapatite crystal was isolated from pooled ileal contents of rats fed a semi-synthetic diet containing bovine beta-casein. The estimated amino acid sequence of the CPP was shorter than that of the trypsin-digested beta-casein but the core region consisting of consecutive bindings of phosphoserine was fully conserved. A moderate and exchangeable binding to Ca2+ of the CPP molecule well substantiates the high absorbability of calcium from milk and dairy products.

Amino Acid Sequence↗
PubMed1991

Preparing well-oriented sols of straight bacterial flagellar filaments for X-ray fiber diffraction.

Well-oriented sols of straight bacterial flagellar filaments have been obtained by preparing reconstituted flagellar filaments with an appropriate length distribution and choosing appropriate solvent conditions. An average filament length of 300 to 500 nm and the use of solvents with very low concentrations of salt has allowed us to prepare highly fluid sols that make flow orientation possible. X-ray fiber diffraction from these sols has shown distinct layer-line reflections to 3.5 A resolution in the meridional direction. Layer-line intensities have been collected by the angular deconvolution method up to 5 A resolution. The possibility of using a magnetic field to further improve the orientation has been explored and a solvent condition that makes flagellar sols sensitive to the magnetic field has been found. General applicability of the method to other systems is also discussed.

Ammonium Sulfate↗
PubMed1991

Poly(vinyl alcohol) hydrogel as an artificial articular cartilage: evaluation of biocompatibility.

We have developed a new poly(vinyl alcohol) hydrogel (PVA-H) of increased physical strength through a new manufacturing process. Its mechanical properties have been found to be preferable as a substitute for articular cartilage. To evaluate its biocompatibility as an artificial articular cartilage, a series of in vivo tests within the intraarticular, as well as the intramuscular, environment were conducted. Tissue reactions of cartilage, bone, synovium, and muscle to PVA-H were studied histologically. In the experimental group, in which PVA-H was implanted, inflammatory reactions of all of these tissues were very slight. In the control group, in which ultra-high molecular weight polyethylene (UHMWPE) was implanted, although tissue reactions of bone and muscle were as slight as in the experimental group, those of cartilage and synovium were somewhat more conspicuous. By way of these findings, the better biocompatibility of PVA-H was documented.

Animals↗
PubMed1991

HLA-DQA1*1 contributes to resistance and A1*3 confers susceptibility to type 1 (insulin-dependent) diabetes mellitus in Japanese subjects.

In this study HLA-DQA1 and TNF genes in addition to HLA-DQB1 gene were investigated at DNA level for elucidation of the genetic backgrounds of Type 1 (insulin-dependent) diabetes mellitus in Japanese subjects. DNA, amplified by polymerase chain reaction, was subjected to allele specific oligonucleotide dot blot analysis, restriction fragment length polymorphism analysis or DNA sequencing. Polymorphism of the TNF gene to NcoI did not correlate with Type 1 diabetes in Japanese patients. DQw1.2 had a protective effect against the disease, the DQA1*1 allele was significantly decreased and DQA1*3 allele was significantly increased. Seventeen out of twenty-two Type 1 diabetic patients (77%) were homozygous for DQA1*3 and five out of twenty-two (23%) heterozygous. The DQA1*3 gene of Type 1 diabetic patients had a normal nucleotide sequence. Furthermore, DQA1*3 was found unexpectedly in two patients without DR4 or DR9. These data indicate that DQA1 gene confers susceptibility and resistance to Type 1 diabetes in Japanese subjects.

Alleles↗
PubMed1991

Fibrolamellar carcinoma of the liver--a case report.

A 36-year-old woman was admitted to our hospital because of general fatigue. The physical and laboratory findings on admission revealed splenomegaly, pancytopenia, hypocoagulopathy, liver hypofunction with a hepaplastin test of 55% and ICG Rmax of 0.6 mg/kg/min. Diagnostic imaging showed a hypoechoic mass 1.5 in diameter a low density area on the CT scan and a faint tumor stain on the AAG in the posterior inferior area of the liver. On a diagnosis of hepatocellular carcinoma with liver cirrhosis and hypersplenism, partial hepatectomy and splenectomy were performed. The resected hepatic specimen revealed a small liver cancer of 1.9 x 1.5 x 1.3 cm with liver cirrhosis. The specimen consisted of a firm rubbery mass. Macroscopically, the tumor appeared oval and was lobulated with a thin capsule. A fibrous scar was observed in the central area. Microscopically, malignant hepatocytes showed various shapes, ranging from polygonal to spindle form, with eosinophilic granular cytoplasm and were surrounded by abundant fibrous stroma. Orcein stain, revealed that these malignant hepatocytes contained many black granules of copper-binding protein. Immunoperoxidase staining for alpha 1-antitrypsin was also positive in the malignant hepatocytes. However, within this lamellar fibrous regions, there were many cords of tumor cells in which nucleoli were absent and abortive biliary differentiation was suggested. Consequently this tumor was diagnosed as an atypical fibrolamellar hepatocellular carcinoma. We think that this case is the 3rd case reported in Japan and the 2nd case in a Japanese person.

Adult↗
PubMed1991

Distribution of fluoride in sound and periodontally diseased human cementum.

Fluoride distribution was investigated by an abrasive micro-sampling technique. The fluoride concentration increased with age in both sound and diseased cementum. In sound teeth, the fluoride profiles (distribution of fluoride from the surface to interior) of the middle and apical cementum were similar. In the diseased cementum the profile of the middle region tended to be more variable than that of the apical cementum, suggesting a possible effect of the oral environment on the fluoride profile at this site.

Adult↗