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C Azuma

Publications and source records attributed to C Azuma.

At least 91 records · Page 5Linked to original sources
PubMed1990

Steroid hormones induce macrophage colony-stimulating factor (MCSF) and MCSF receptor mRNAs in the human endometrium.

We investigated the biological effects of sex-steroid hormones, secreted from the corpus luteum and placenta, on the induction of mRNAs encoding macrophage colony-stimulating factor (MCSF) and c-fms proto-oncogene (MCSF receptor) in human endometrium. RNA was extracted from the placenta and endometrium of both pregnant and non-pregnant women, and Northern blot analysis was performed on poly(A)+ RNA using MCSF or c-fms proto-oncogene cDNA as the probe. Results showed: (1) that MCSF mRNA was expressed in the placenta and endometrium of the pregnant uterus, (2) that c-fms proto-oncogene mRNA was also expressed in the placenta and endometrium of the pregnant uterus, and (3) that exogenous sex-steroid hormones could induce the expression of MCSF and c-fms proto-oncogene mRNAs in the endometrium of non-pregnant women. These results indicate that sex-steroid hormones secreted by the corpus luteum and/or placenta influence endometrial and placental growth and differentiation via a mechanism of action involving local production of MCSF and its receptor.

Corpus Luteum↗
PubMed1989

Vertical transmission of human T-cell leukemia virus type I (HTLV-I): detection of proviral DNA in HTLV-I carrier gravida.

The seroprevalence rate of human T-cell leukemia virus type I (HTLV-I) in pregnant women in the Osaka district was determined by enzyme-linked immunosorbent assay and Western blot analysis. Twenty-one (1.0%) of 2192 samples tested were positive for both assays and the seropositive parturients were found to be integrated with HTLV-I proviral DNA in their mononuclear cells by a DNA dot blot hybridization assay using HTLV-I DNA probe or by a selective DNA amplification technique using the polymerase chain reaction (PCR). On the other hand, proviral DNA was not detected in cord blood of the neonates born to the carrier mothers, indicating that transplacental infection of HTLV-I during pregnancy could be excluded. The results support the hypothesis that postpartum infection via breast milk plays a significant role among the possible perinatal transmission routes.

Carrier State↗
PubMed1989

Zygosity determination of multiple pregnancy by deoxyribonucleic acid fingerprints.

We used a new method of deoxyribonucleic acid analysis to determine zygosity in multiple pregnancies. This method uses a minisatellite core probe, requires only a small amount of deoxyribonucleic acid, and detects the restriction fragment length polymorphisms that are a result of allelic differences in the number of tandem repeats that contain the core sequence. Southern blot hybridization showed an individual-specific deoxyribonucleic acid fingerprint and each polymorphic band in the sibling could be identified within one (but not both) of the parents. Identical deoxyribonucleic acid fingerprints among the siblings of multiple pregnancy indicate they must be monozygotic. This method is sufficiently reliable and rapid so the determination of zygosity in multiple pregnancy can be made the same day the fetal deoxyribonucleic acid is made available.

DNA↗
PubMed1988

Biased expression of variable region gene families of the immunoglobulin heavy chain in autoimmune-prone mice.

We have examined usage of variable region gene families of the immunoglobulin heavy chain (VH gene family) in spleens of MRL/MpJ-1pr/lpr (MRL/lpr), (NZB x NZW)F1, and BXSB mice by Northern analysis using various VH probes, including the VHPAR gene which we cloned and identified as a gene encoding the heavy-chain variable region of antipoly(ADP-ribose) antibody. The amount of VHS107 family mRNA was almost constant for the same amount of splenic crude RNA in autoimmune-prone and normal mice, while concentrations of other family mRNAs were elevated in autoimmune-prone mice. For example, per splenic RNA the VHPAR family was expressed in MRL/lpr mice 10 times more than in their normal counterpart, MRL/MpJ-+/+ (MRL/+) mice. These results indicate the bias of VH gene usage in autoimmune-prone mice. Expression of the VHS107 family was depressed from an early life stage of MRL/lpr and male BXSB mice. Furthermore, the expression of IL-4 and IL-5 were quantitatively compared, as B cell differentiation factor was thought to be produced by abnormally proliferative T cells in lymph nodes of MRL/lpr mice. We could not, however, observe overproduction of IL-4 and IL-5 mRNA in the lymph nodes.

Amino Acid Sequence↗
PubMed1987

IgG1 induction factor: a single molecular entity with multiple biological functions.

A cDNA clone coding for the murine IgG1 induction factor has been isolated. The translation products directed by this clone were analyzed in different biological assays. The data obtained show that the IgG1 induction factor: Is involved in the regulation of IgG responses, by increasing IgG1 and decreasing IgG3 and IgG2b secretion; Induces hyper-Ia expression on resting B lymphocytes; Synergizes with anti-Ig in inducing DNA synthesis in resting B lymphocytes; Synergizes with DxS in inducing DNA synthesis by B lymphocytes; It induces DNA synthesis by either the T cell line CTL-L or Con-A blasts. Thus, this lymphokine in addition to IgG1 inducing activity has also BSF-1, BCGF-II and TCGF like activities. The fact that a single molecule can perform all the above listed functions has implications for our view of lymphocyte activation. It indicates that considering the B cell response as an ordered series of independently controlled events, is an oversimplified view of the dynamic process through which B cells are activated and also indicate the functional interconnection of the different elements of the immune system.

Amino Acid Sequence↗
PubMed1987

Growth factors and receptors of lymphocytes.

To understand molecular mechanisms of clonal expansion of lymphocytes we have isolated cDNA clones for two lymphokines, interleukins (IL) 4 and 5 that induce proliferation and maturation of B-lymphocytes. Structures of IL-4 and IL-5 revealed a remote homology with other lymphokines such as IL-3 and gamma-interferon. IL-4 and IL-5 were shown to affect not only B-lymphocytes but also T-lymphocytes and several other cells derived from bone marrow stem cells. We have also studied the structure and function of the IL-2 receptor: our focus was the molecular basis for the high and low affinity states of the receptor encoded by the identical cDNA. We propose the affinity conversion model that the high-affinity state of the IL-2 receptor is a ternary complex of IL-2, the IL-2 receptor, and a postulated "converter protein", which is fewer in number than the receptors.

Animals↗
PubMed1986

Cloning of cDNA for human T-cell replacing factor (interleukin-5) and comparison with the murine homologue.

We have cloned cDNA for T-cell replacing factor (interleukin-5), which replaces T-cell helper function for normal B cells which secrete immunoglobulin, from human T cell leukemia line, ATL-2, using mouse interleukin-5 cDNA as probe. Total nucleotide sequence of the cDNA (816 base pairs) was determined and compared with that of mouse interleukin-5 cDNA. The cloned cDNA encoded the interleukin-5 precursor of 134 amino acids containing an N-terminal signal sequence. Although the human interleukin-5 precursor is one amino acid longer than the murine homologue, the sizes of the mature proteins appear similar. The nucleotide and amino acid sequence homologies of the coding regions of human and murine interleukin-5 are 77% and 70%, respectively. Human interleukin-5 synthesized by the direction of the cloned cDNA induced immunoglobulin synthesis in human B cells stimulated by Staphylococcus aureus mitogen.

Amino Acid Sequence↗
PubMed1982

Auditory brainstem response (ABR) in infantile Gaucher's disease.

The auditory brainstem response (ABR) was studied in an infant with Gaucher's disease. The infant was normal until the age of three months. His illness began with stridor, strabismus, inguinal hernia and failure to thrive. Thereafter, muscular rigidity with opisthotonus, ocular palsies, difficulty in swallowing and respiratory failure due to central origin developed. He died of respiratory failure due to central origin developed. He died of respiratory failure at the age of one year and four months. The ABR was abnormal at six and eight months of age. Initially, at the age of six months, there was a lengthening of the peak latencies of wave I, II and III and disappearance of the waves after IV. But at eight months, more marked lengthening of the peak latencies of the waves and the disappearance of waves after III were noted as his general condition deteriorated. The autopsy revealed relative preservation of the nuclei and tracts of the auditory pathways in the brainstem. The ABR was useful for monitoring the progress of the disease in this patient because it made detection of brainstem lesions possible.

Adult↗
PubMed1977

Effects of sex hormones on oncogenesis in rat urinary bladder by N-butyl-N-(4-hydroxybutyl)-nitrosamine.

The effects of testosterone propionate, estradiol, and estriol on the oncogenesis of male rats' bladder induced by oral administration of the carcinogen N-butyl-N-(4-hydroxybutyl)-nitrosamine (BBN) were examined. There were significant differences between the testosterone propionate-administered and estradiol-administered groups and also between the testosterone propionate-administered and estriol-administered groups in the incidence of bladder tumors.

Animals↗
PubMedDate not supplied

A new approach using DNA fingerprinting for the determination of androgenesis as a cause of hydatidiform mole.

A new method of DNA analysis has been used for the determination of androgenesis as a cause of complete hydatidiform mole. This method, using a minisatellite core probe, requires only a small amount of DNA and detects the restriction fragment length polymorphisms (RFLPs) due to allelic differences in the number of tandem repeats containing the core sequence. Southern blot hybridization showed an individual-specific DNA fingerprint, and each polymorphic band in molar tissues could be identified as being of paternal, but not maternal, origin. Some polymorphic bands of paternal DNA were not observed in molar tissues, indicating that endoreduplication of a normal haploid sperm or fertilization by dispermy to an anuclear oocyte with no effective genome could be the cause of complete hydatidiform mole. This method is sufficiently reliable and rapid that differential diagnosis could be made between complete hydatidiform mole, partial mole and hydropic change.

Adolescent↗
PubMedDate not supplied

Cloning of cDNA encoding the murine IgG1 induction factor by a novel strategy using SP6 promoter.

Complementary DNA encoding the IgG1 induction factor, the first lymphokine directed to B lymphocytes, from a murine T-cell line has been cloned using a new strategy. The putative primary amino-acid sequence was deduced from the nucleotide sequence determined. The lymphokine synthesized by the direction of this cloned cDNA has many other functions, such as production of B-cell growth factor-1 and induction of Ia on B cells.

Amino Acid Sequence↗
PubMedDate not supplied

Cloning of complementary DNA encoding T-cell replacing factor and identity with B-cell growth factor II.

Proliferation and maturation of antigen-stimulated B cells are regulated by several soluble factors derived from macrophages and T cells. These soluble factors are functionally divided into two groups: B-cell growth factor (BCGF), thought to be involved in B-cell proliferation; and B-cell differentiation factor (BCDF), responsible for maturation of activated B cells into immunoglobulin-secreting cells. This classification needs to be re-examined in the light of the recent cloning of complementary DNA encoding IgG1 induction factor (interleukin-4, IL-4) from the 2.19 mouse T-cell line. Recombinant IL-4 has BCGF and BCDF activities and affects B cells, T cells and mast cells (refs 7, 8; our unpublished data). Another well-characterized B-cell factor is T-cell replacing factor (TRF), which, when secreted by the murine T-cell hybridoma B151K12, is defined by two activities: induction of IgM secretion by BCL1 leukaemic B-cell line; and induction of secondary anti-dinitrophenol (DNP) immunoglobulin G (IgG) synthesis in vitro by DNP-prime B cells. Although TRF from B151K12 was classified as BCDF, purified TRF has BCGF-II activity. To elucidate the molecular properties of TRF we isolated cDNA encoding TRF from the 2.19 T-cell line and report here the structure and multiple activities of this lymphokine.

Animals↗