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T Niiyama

Publications and source records attributed to T Niiyama.

18 recordsLinked to original sources
PubMed1997

Accumulation of mitochondrial ATP synthase subunit c in muscle in a patient with neuronal ceroid lipofuscinosis (late infantile form).

We report a case late infantile neuronal ceroid lipofuscinosis (NCL). Abnormal granules were found in the skeletal muscle fibers, Schwann cells, perineurial cells, endothelial cells, fibroblasts, and perivascular smooth muscle cells in the sural nerve. Electron microscopy revealed that these granules showed fingerprint profiles, curvilinear profiles or membrane-bound membranous structures. Acid phosphatase reaction was increased in these cells. Immunohistochemical studies for mitochondrial ATP synthase subunit c showed a strong reaction in these cells, suggesting abnormal accumulation of subunit c. Immunohistochemistry for subunit c in muscle may be useful in the diagnosis of late infantile NCL.

Adult↗
PubMed1994

Chromosomal assignment of HepG2 3'-directed partial cDNA sequences by Southern blot hybridization using monochromosomal hybrid cell panels.

Large-scale sequencing of a 3'-directed cDNA library from the human liver cell line HepG2 has generated several hundred species of cDNA gene signatures, about 85% of which identify novel genes. They are useful molecular landmarks for human genome mapping. We used 160 of these novel signatures as probes for Southern hybridization to human DNA. We then identified the copy number of the corresponding genes and assigned them to chromosomes, with reference to monochromosomal hybrid cell mapping panels. The distribution profile of the expressing genes among chromosomes suggested that the expressing gene density is not uniform.

Animals↗
PubMed1994

Gnome--an Internet-based sequence analysis tool.

Gnome (GenomeNet Open Mail-service Environment) is a sequence analysis tool that enables an end-user to make use of several Internet- (mainly e-mail) based services with an easy-to-use graphical user interface. Users can conduct homology and motif searches, and database-entry retrieval against the latest databases by emitting search requests to and receiving their results form a search-server by e-mail. The search results are viewed and managed efficiently with this system. The Macintosh and X (Motif) versions of the Gnome client and the UNIX version of the Gnome server are available to academic users free of charge.

Computer Communication Networks↗
PubMed1994

Dystrophin-related protein in Becker muscular dystrophy.

A benign Becker muscular dystrophy (BMD) patient with a marked decrease in dystrophin exhibited remarkable expression of dystrophin-related protein (DRP) on most of the muscle cell membrane. A phenotypic Duchenne muscular dystrophy patient with a truncated form of dystrophin exhibited no DRP expression on the muscle cell membrane except for the neuromuscular junction. Increased DRP expression might compensate for a lack of dystrophin in some BMD patients.

Adolescent↗
PubMed1992

Large scale cDNA sequencing for analysis of quantitative and qualitative aspects of gene expression.

Large scale sequencing of cDNAs provides a complementary approach to structural analysis of the human genome by generating expressed sequence tags (ESTs). We have initiated the large-scale sequencing of a 3'-directed cDNA library from the human liver cell line HepG2, that is a non-biased representation of the mRNA population. 982 random cDNA clones were sequenced yielding more than 270 kilobases. A significant portion of the identified genes encoded secretable proteins and components for protein-synthesis. The abundance of cDNA species varied from 2.2% to less than 0.004%. Fifty two percent of the mRNA were abundant species consisting of 173 genes and the rest were non-abundant, consisting of about 6,600 genes.

Base Sequence↗
PubMed1991

A novel system for large-scale sequencing of cDNA by PCR amplification.

We have developed a method for constructing a library containing the 3' end fragment of cDNA for large-scale sequencing of cDNA clones. The average size of the insert was 270 bp. Cell lysates that carry plasmids having the cDNA insert were subjected to PCR amplification of the cDNA moiety and the products were subjected to sequencing analysis using an autosequencer. With this protocol, sample preparation became a non-limiting step, that allowed us to sequence as many samples as the autosequencer could handle.

Base Sequence↗
PubMed1988

The functional link between the immune suppression gene and Mhc class II molecules.

The immune response to bovine insulin (BI) in the rat is controlled by the major histocompatibility complex (Mhc)-linked immune response gene (Ir-BI) and immune suppression gene (Is-BI). In the present study, we investigated the low responsiveness to BI in the WKAH rat (RT1k) and attempted to explore the functional link between Is-BI and Mhc class II molecules. Lymph node cells (LNC) from the low responder (WKAH) rats responded well to BI when a large amount of antigen was added to the culture in vitro or after OX8-bearing (OX8+) T cells were eliminated. These LNC, after the elimination of OX8+ cells, could show the RT1.Dk-restricted proliferative response upon in vitro challenge with BI, BI-B chain, or pork insulin. In addition, OX8+ T cells, which were activated with BI and antigen-presenting cells (APC) in vitro, suppressed the anti-BI response of W3/25-bearing proliferating T cells from BI-immunized rats. The results have demonstrated that proliferating T-cell repertoires do exist to BI, which recognize BI-B chain in the context of RT1.Dk molecules in the WKAH rat, and that the state of low responsiveness is mediated to a great extent by antigen-specific OX8+ suppressor T (Ts) cells. Furthermore, the elimination of APC or the addition to RT1.Bk-specific monoclonal antibody in the in vitro secondary activation culture of Ts cells diminished the suppressive activity of OX8+ Ts cells. In the induction phase of Ts cells it therefore seems to be necessary for these cells to recognize BI together with RT1.Bk molecules on APC.

Animals↗
PubMed1987

Genetic control of the immune responsiveness to Streptococcus mutans by the major histocompatibility complex of the rat (RT1).

The lymph node cells from 11 strains of rats, differing in the genotype of the major histocompatibility complex of the rat (RT1), were examined on the basis of their proliferative response to the cell wall antigen of Streptococcus mutans. The 11 rat strains fell into three groups: high, intermediate, and low responders. To demonstrate the influence of the major histocompatibility complex on immune responsiveness to S. mutans, further experiments were performed using the RT1-congenic rat strains WKAH.1L(LEW), WKAH. 1AV1(ACI), and WKAH.1J(LEJ), which differ only in the genotype of the RT1 region. Although the background genes of each strain were of WKAH origin, WKAH.1L(LEW) and WKAH.1AV1(ACI) rats showed a low response whereas WKAH.1J(LEJ) rats showed a moderate response to the S. mutans cell wall antigen. The results indicate that the immune response is controlled by the class II gene(s) in RT1. Furthermore, the RT1.D locus products were shown to play an important role in the restriction molecule, since a monoclonal antibody, HOK7, directed to the RT1.Dk locus products reduced the proliferative response of lymph node cells.

Animals↗
PubMed1987

[The analysis of the immune response to Streptococcus mutans cell wall antigen and allo-MHC antigens in the rat].

RT1 is the major histocompatibility complex (MHC) of the rat, which is equivalent to H-2 of mice and HLA of human. In the present study, the role of RT1, especially class II antigens (RT1-B/D antigens) in the immune response to Streptococcus mutans cell wall antigen (SMA) and allo-MHC antigens was investigated. The results are as follows. 1) Eleven strains of inbred rats were divided into high or low responders with respect to their immune responsiveness to SMA. 2) Having examined the immune responsiveness to SMA of RT1-congenic strains, it is shown that there is a correlation between the immune responsiveness and RT1 haplotypes. 3) The low responsiveness to SMA of LEW rats was mostly mediated by MRC-OX8+ suppressor T cells. 4) By the inhibition test of allo-MLR (mixed lymphocyte reaction) with monoclonal antibodies, HOK7 HOK12 and HOK33, it has been shown that RT1-B/D antigens are MLR-stimulatory molecules and that Ia+ antigen presenting cells (APC) of responder cells are necessary in the recognition of allo-MHC antigens. 5) It is suggested that there are two recognition pathways of allo-MLR. In one of them, allo-MHC antigens are directly recognized by responder T cells, in another, they are recognized by responder T cells with help of Ia+ APC.

Animals↗
PubMedDate not supplied

Ir gene for bovine insulin in the rat maps to RT1.B beta.

The genetic control of the immune response to bovine insulin (BI) in the rat was investigated. As a result of experiments utilizing two intra-MHC recombinant rats and of blocking experiments with monoclonal antibodies against MHC class II antigens, an immune response gene for BI in the rat could be mapped to the RT1.B beta locus.

Animals↗