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S Mizuno

Publications and source records attributed to S Mizuno.

At least 181 records · Page 10Linked to original sources
PubMed1997

The cDNA cloning and transient expression of a chicken gene encoding a follicle-stimulating hormone receptor.

A clone, pcFSHR, containing a 3.1-kb insert was isolated from a cDNA library of chicken ovarian follicles by screening with an RT-PCR-generated cDNA probe for a putative N-terminal half-region of chicken FSH-R. The deduced amino acid sequence of pcFSHR exhibits about 84% identity to those of mammalian FSH-R and about 70% to those of mammalian LH-CG-R. Northern blot analysis for total RNA preparations from several chicken tissues revealed that transcripts detected with pcFSHR were present exclusively in ovary and testis. In a chicken ovary, the transcripts were detected in granulosa but not in theca cells. A radioligand receptor assay for the human 293 cells transfected with an expression vector containing the insert of pcFSHR demonstrated the production of a receptor which showed about 10-fold higher affinity for chicken FSH than for chicken LH. The affinity for chicken FSH was significantly higher than for human FSH. In consistency with the ligand specificity of the receptor, a significantly higher level of intracellular accumulation of cAMP was detected when the transfected cells were treated with chicken FSH than with chicken LH. From these results, we conclude that pcFSHR is a cDNA clone for the chicken FSH-R.

Amino Acid Sequence↗
PubMed1997

Expression of CD44 variants in gastric carcinoma with or without Epstein-Barr virus.

The significance of CD44 variants in gastric carcinoma has not been fully investigated in terms of the pathological features of the carcinoma, including its association with Epstein-Barr virus (EBV). In this study, a total of 104 primary gastric carcinoma tissues (EBV-associated gastric carcinomas, EBVaGC, and EBV-negative carcinomas) were evaluated by immunohistochemistry. When the immunoreactivity of formalin-fixed, paraffin-embedded sections was graded on a scale of 0-3, the frequencies of grades 0-1, 2 and 3 were, respectively, 77%, 16% and 7% using monoclonal antibody (MAb) 3G5, which recognizes V3-5, and 70%, 14% and 15% with MAb 2F10, which recognizes V6. The expression of CD44 variants is independently correlated with lymph node metastasis and EBV-association in gastric carcinoma. Significant correlations were observed between V3-5 expression and lymph vessel invasion or lymph node metastasis, and between V6 expression and lymph node metastasis. The expression of both variants was significantly correlated with EBV-association. EBV-association and lymph node metastasis contributed independently to CD44 variant expression by multivariate analysis. Thus, the mechanism and significance of CD44 variant-expression are different in gastric carcinomas with or without EBV. EBVaGC is a distinct type of gastric carcinoma which should be considered separately from EBV-negative carcinoma.

Adolescent↗
PubMed1997

Expression of a neutrophil chemotactic protein LECT2 in human hepatocytes revealed by immunochemical studies using polyclonal and monoclonal antibodies to a recombinant LECT2.

A recombinant human neutrophil chemotactic protein LECT2 (rhLECT2) was purified as a 16-kDa protein from the culture fluids of stable transfectants derived from CHO cells (clone C1D8-1) and L929 cells (clone L2E4-1). The N-terminal amino acid sequence of the protein secreted by both clones were homologous to the previously described bovine LECT2. We produced polyclonal and monoclonal antibodies against rhLECT2 and investigated secretion of LECT2 protein in six human hepatoma cell lines, which express LECT2 mRNA, and in hepatocytes of normal human livers by a sandwich enzyme-linked immunosorbent assay and by immunostaining using the antibodies, respectively. We revealed that five of six hepatoma cell lines secreted LECT2 into culture fluids at concentrations of 30-135 ng/mg. We also demonstrated that the cytoplasm of human hepatocytes was diffusely stained, although periportal hepatocytes tended to be weakly and granularly stained by immunostaining. These results indicated that the novel protein was expressed in hepatocytes and suggested an important role of LECT2 in the cells in addition to the activation of neutrophils.

Animals↗
PubMed1997

Induction of p27Kip1 degradation and anchorage independence by Ras through the MAP kinase signaling pathway.

While most untransformed cells require substrate attachment for growth (anchorage dependence), the oncogenic transformed cells lack this requirement (anchorage independence) and are often tumorigenic. However, the mechanism of loss of anchorage dependence is not fully understood. When rat normal fibroblasts were cultured in suspension without substrate attachment, the cell cycle arrested in G1 phase and the cyclin-dependent kinase inhibitor p27Kip1 protein and its mRNA accumulated. Conditional expression of oncogenic Ras induced the G1-S transition of the cell cycle and significantly shortened the half-life of p27Kip1 protein without altering its mRNA level. Inhibition of the activation of mitogen-activated protein (MAP) kinase by cyclic AMP-elevating agents and a MEK inhibitor prevented the oncogenic Ras-induced degradation of p27Kip1. These results suggest that the loss of substrate attachment induces the cell cycle arrest through the up-regulation of p27Kip1 mRNA, but the oncogenic Ras confers anchorage independence by accelerating p27Kip1 degradation through the activation of the MAP kinase signaling pathway. Furthermore, we have found that p27Kip1 is phosphorylated by MAP kinase in vitro and the phosphorylated p27Kip1 cannot bind to and inhibit cdk2.

Amino Acid Sequence↗
PubMed1997

Association of HSP73 with the acquired resistance to uranyl acetate-induced acute renal failure.

Studies were performed to investigate the relationship between heat shock protein (HSP) and the acquired resistance to uranyl acetate (UA)-induced acute renal failure (ARF). Rats were resistant to a rechallenge with 5 mg/kg of UA between 1 and 2 weeks after the first injection of the same amount of UA. During this period, the renal HSP73 was increased to 148 +/- 12% of baseline, and tubular damage as well as an increase in serum creatinine after the second challenge of UA were significantly lower than existing after the first challenge. At 4 weeks after the first injection of UA, the amount of HSP73 returned to the normal level, and serum creatinine at the 5th day after the second challenge was increased to a level equivalent to that after the first injection. A lower dose of UA (2 mg/kg) had a little effect on the renal HSP73 content and induced limited resistance to 5 mg/kg of UA at 2 weeks after the first injection. Whole-body hyperthermia markedly increased the renal HSP72 content, but not that of HSP73, and did not induce resistance to UA. These data suggest that the increase in renal HSP73 might be associated with the acquired resistance to UA in rats, although there is no direct evidence that HSP73 produced by the regenerated cells plays a role in the acquired resistance.

Animals↗
PubMed1997

Inhibition of anchorage-independent growth of ras-transformed cells on polyHEMA surface by antisense oligodeoxynucleotides directed against K-ras.

We examined the effect of antisense oligodeoxynucleotides (AS ODNs) directed against v-Ki-ras on the anchorage-independent growth of v-Ki-ras-transformed rat fibroblasts using plates coated with an antiadhesive polymer, poly(2-hydroxyethyl methacrylate) (polyHEMA). Among AS ODNs tested, 17mer AS ODN centered around codon 12 of v-Ki-ras inhibited the v-Ki-Ras expression and v-Ki-Ras-induced anchorage-independent growth, while its sense sequence did not affect it. Using polyHEMA plates, the direct addition of AS ODNs to the cells growing anchorage-independently and various treatment schedules of AS ODNs are now available to identify the most desirable conditions for AS ODNs treatment.

Animals↗
PubMed1997

The cDNA cloning and transient expression of a chicken gene encoding cytochrome P-450scc.

A cDNA clone, pcSCC1, isolated from a chicken adrenal gland library showed about 62% nucleotide sequence similarity to those of mammalian and rainbow trout P-450scc cDNAs and was proved to be the clone for chicken P-450scc by the enzymatic activity of converting 25-hydroxycholesterol to pregnenolone demonstrated in the transfected COS-7 cells. Comparison of deduced amino acid sequences shows significant conservation of heme- and steroid-binding domains but little similarity in the putative N-terminal presequence region among chicken, trout and mammals. The chicken cDNA lacks a polyadenylation signal in its 3'-UTR. Sequencing of a 3' end region of the P-450scc gene (CYP11A1) suggests that a region containing the polyadenylation signal is spliced out from the pre-mRNA.

Amino Acid Sequence↗
PubMed1997

In vitro confirmation of newly established lung cancer cell lines using flow cytometry and multicellular tumor spheroids.

We report on a simplified method of cytomorphological in vitro confirmation of newly established lung cancer cell lines by using multicellular tumor spheroids (MTS) and flow cytometry (FCM). Eleven cell lines were established from 11 patients with lung cancer. The MTS were produced by culturing cells in agar-coated dish. Cytomorphological studies were made using smears of crushed MTS and frozen sections of MTS. The MTS were fixed doubly with paraformaldehyde and osmic acid for scanning and transmission electron microscopy. Bivariate fluorescence of fluorescein isothyocyanate (FITC, tumor associated antigen, TAA) and propidium iodide (DNA) were measured by FCM. The MTS grew anchorage-independently. Cytopathological and electron microscopic findings of MTS were similar to those of the original clinical specimens. The DNA index and TAA were useful in evaluating the presence or absence of contamination by cells of non-tumor origin. The new cell lines satisfied a minimum of four conditions to confirm their establishment: (a) they originated from humans, (b) they were cytomorphologically identified with specimens from primary lesions, (c) they showed tumorigenicity, and (d) they were free from contamination by cells of different origin. From these findings, the establishment of new cell lines can be confirmed in vitro by using MTS and FCM.

Antigens, Neoplasm↗
PubMed1997

Granulocyte colony-stimulating factor-combined marrow-ablative chemotherapy and autologous blood cell transplantation for the treatment of patients with acute myelogenous leukemia in first remission. The Fukouka Bone Marrow Transplant Group.

We conducted a clinical trial to increase the chemosensitivity of residual leukemic cells by combining G-CSF to marrow-ablative chemotherapy, including cytosine arabinoside (Ara-C), and facilitated by autologous blood cell transplantation (ABCT) for treatment of acute myelogenous leukemia (AML) in first complete remission. A total of 16 patients were consecutively treated with granulocyte colony-stimulating factor (G-CSF)-combined high-dose chemotherapy (busulfan, etoposide and Ara-C) followed by autotransplantation of peripheral blood progenitor cells, which had been collected after the consolidation chemotherapy. At a median follow-up time of 44.5 months, the probability of 5-year event-free survival was 74.5% with only three leukemic relapses. This preliminary observation suggests the effectiveness of G-CSF-combined conditioning and ABCT as a post-remission therapy for AML.

Adolescent↗
PubMed1997

Molecular characterization and cytological mapping of a non-repetitive DNA sequence region from the W chromosome of chicken and its use as a universal probe for sexing carinatae birds.

A non-repetitive genomic DNA region of about 25 kb was cloned from the W chromosome of chicken using a genomic library prepared from a single W chromosome of the chicken. This region was mapped by fluorescence in situ hybridization (FISH) with mitotic and lampbrush chromosomes to a position between the major EcoRI family and the pericentromeric Xhol family on the W chromosome. A 0.6-kb EcoRI fragment (EE0.6) subcloned from this region consists of a sequence that can be obtained by the exon-trapping procedure and flanking sequences. Sequences, which are closely similar to that of EE0.6, are widely conserved on the W chromosomes of Carinatae birds, as revealed by Southern blot hybridization to HindIII-digested female and male genomic DNAs from 18 species of birds belonging to eight different taxonomic orders. The female sex of those birds can be determined by the presence of an unambiguous female-specific band. For many species of birds, the female sex can also be determined by polymerase chain reaction (PCR) using a set of primers from the flanking sequences in the chicken EE0.6.

Animals↗
PubMed1997

Helicobacter pylori infection and gastric cancer. A nested case-control study in a rural area of Japan.

We conducted a seroepidemiological nested case-control study to determine the association of gastric cancer with Helicobacter pylori infection and atrophic gastritis. A cohort of 2858 participants in an annual multiphasic health check-up were followed for eight years. Data for 45 gastric cancer cases and 225 sex-, age-, and address-matched control subjects were analyzed. Helicobacter pylori infection was determined by IgG antibodies, and atrophic gastritis was diagnosed by both serum pepsinogen I level (< or = 70 ng/ml) and the pepsinogen I/II ratio (< or = 3.0). Univariate analysis showed that Helicobacter pylori and atrophic gastritis were significantly associated with gastric cancer. In a multivariate analysis, atrophic gastritis was associated with significantly increased risk of cancer (odds ratio, 3.38; 95% confidence interval, 1.54-7.42); however, Helicobacter pylori was not associated with cancer (odds ratio, 1.84; 95% confidence interval, 0.59-5.72). These results suggest that Helicobacter pylori infection alone is not directly associated with gastric carcinogenesis but has an indirect relation to gastric cancer through the development of atrophic gastritis.

Adult↗
PubMed1997

Increased incidence of cytomegalovirus (CMV) infection and CMV-associated disease after allogeneic bone marrow transplantation from unrelated donors. The Fukuoka Bone Marrow Transplantation Group.

Cytomegalovirus (CMV) infection and CMV-associated disease were monitored using the CMV antigenemia assay in 72 patients who received allogeneic bone marrow transplantation (BMT), and their incidences were compared between related and unrelated donor transplant patients. The incidence of CMV infection after BMT was significantly higher in patients who received transplants from HLA-matched unrelated donors than from HLA-matched sibling donors (87% vs 53%, P < 0.05). CMV-associated disease developed in 73% of unrelated and in 14% of sibling donor transplant patients (P < 0.01). The peak levels of CMV antigenemia were significantly higher in unrelated donors than in sibling donor transplant patients (16 vs 1 CMV antigen-positive cells per 50000 WBCs, P < 0.01). The median number of CMV antigen-positive cells on first detection was also significantly higher in unrelated donor transplant patients (15 vs 1, P < 0.01). The detection of CMV antigen-positive cells preceded the development of CMV-associated disease in 18% of unrelated donor transplant patients, suggesting a lower predictive value of CMV antigenemia for subsequent CMV-associated disease in unrelated donor BMT. Careful monitoring and further studies are needed for the early diagnosis and prevention of CMV-associated disease in unrelated donor BMT.

Adolescent↗
PubMed1997

The effects of a simplified method for cryopreservation and thawing procedures on peripheral blood stem cells.

A simplified method for cryopreservation at -80 degrees C of peripheral blood stem cells (PBSC) has been increasingly used for autologous PBSC transplantation in Japan. Although this method, using 6% hydroxyethyl starch (HES) and 5% dimethyl sulfoxide (DMSO) as a cryoprotectant without rate-controlled freezing, has several advantages over the conventional method using 10% DMSO with rate-controlled freezing, little is known about effects of long-term cryopreservation for years and thawing process on hematopoietic progenitors. We examined the recovery rates of BFU-E and CFU-GM in sample tubes cryopreserved by the simplified method under various conditions as follows: (1) long-term storage for 1-5 years; (2) DMSO exposure for 1 h after rapid thawing; and (3) thawing at a lower temperature other than 37 degrees C. In our study, we found that the recovery rates of BFU-E and CFU-GM were not affected by the length of cryopreservation period; they remained at more than 70% on average for 16-61 months. In our hands, a 1-h exposure to DMSO after rapid thawing was not toxic for hematopoietic progenitors. Furthermore, there was no significant difference in the recovery rates of BFU-E and CFU-GM between thawing at 37 degrees C and 20 degrees C. These observations indicate that PBSC cryopreserved for at least 5 years by the simplified method can be used clinically without losing hematopoietic activity, and suggest that hematopoietic activity of the thawed PBSC may be unaffected when PBSC are infused slowly within 60 min or even when PBSC are thawed gradually at room temperature.

Blood Preservation↗
PubMed1997

Autologous peripheral blood stem cell transplantation for acute myelogenous leukemia.

The safety and efficacy of myeloablative therapy followed by autologous peripheral blood stem cell transplantation (ABSCT) for acute myelogenous leukemia (AML) were evaluated in 60 patients. Peripheral blood stem cells (PBSC) were collected during recovery after consolidation chemotherapy. High-dose chemotherapy consisting of busulfan (16 mg/kg), etoposide (40 mg/kg), and cytosine arabinoside (3 g/m2 x 4) (BEA regimen) was used for pretransplant conditioning in 13 patients. For the remaining 47 patients, granulocyte colony-stimulating factor (G-CSF) was administered concurrently with the BEA regimen during conditioning. Unpurged, cryopreserved PBSC containing a median number of 5.4 x 10(8) MNC/kg or 12 x 10(4) CFU-GM/kg were reinfused at transplantation. The median number of days to granulocytes exceeding 500/microl and last platelet transfusion were 15 (8-44) and 24 (0->180), respectively. The 3-year probabilities of disease-free survival (DFS) and relapse were 78.6 and 21.4% for patients transplanted in first remission, 29.6 and 64.4% for those in second or third remission, and 11.1 and 77.8% for those in relapse, respectively. There were no transplant-related deaths within 100 days of transplantation. Age, disease status at transplantation, and number of induction chemotherapies to first complete remission were risk factors affecting the outcome of ABSCT. These results of ABSCT for AML in first remission warrant a prospective study of ABSCT as post-remission therapy.

Acute Disease↗
PubMed1997

Predominant expression of a Z-chromosome-linked immunoglobulin superfamily gene, ZOV3, in steroidogenic cells of ovarian follicles and in embryonic gonads of chickens.

A cDNA clone, pZOV3, was isolated from the cDNA library of immature chicken ovaries and its gene was mapped to the middle of the short arm of the Z chromosome. The cDNA sequence suggests that ZOV3 is a novel member of the immunoglobulin superfamily. cDNA clones of homologues of chicken ZOV3 were also obtained from Japanese quail and pigeon. Northern blot hybridization suggests that the high-level expression of the ZOV3 gene is restricted to the gonads: embryonic, immature and mature ovaries, and embryonic and immature testes. Western blot analysis and immunocytological detection using specific polyclonal antibodies against amino- and carboxyl-terminal regions of ZOV3 demonstrate that ZOV3 is a plasma membrane-bound glycoprotein that exists in granulosa cells and islets of cells in the theca externa layer of ovarian follicles. The latter islets coincide with those producing estradiol-17 beta. In male and female embryos, production of ZOV3 is first prominent in medullary and seminiferous codes, respectively, of developing gonads. Then, after hatching, it is shifted to the cortex surrounding the primitive follicles in the ovary or is continued weakly in the primary seminiferous tubules in the testis. Expression of the ZOV3 gene and production of ZOV3 are no longer detectable in the mature testis. ZOV3 is unique among the immunoglobulin superfamily proteins in that it is produced predominantly in gonads. Its possible role in differentiation or maintenance of steroidogenic cells in an ovarian follicle is discussed.

Amino Acid Sequence↗
PubMed1997

De novo mutation of the platelet glycoprotein Ib alpha gene in a patient with pseudo-von Willebrand disease.

Pseudo (or platelet-type)- von Willebrand disease (vWD) is a very rare autosomal dominant bleeding disorder caused by an abnormal hyper-responsiveness of the platelet membrane glycoprotein (GP) Ib/IX complex, the receptor for von Willebrand factor. We found a heterozygous missense mutation in the GPIb alpha gene in a sporadic case with pseudo-vWD: Met (ATG) to Val (GTG) at residue 239. The mutation was not detected in either parent. Investigation of three variable number of tandem repeat loci, D1S80 (MCT118), vWA and D17S5 (YNZ22), confirmed paternity and the de novo origin of the mutation. Furthermore, we have shown by the TaqI polymorphism analysis, which is located downstream of the GPIb alpha gene, that the mutation occurred in the maternal allele. This is the first description of de novo mutation occurred in pseudo-vWD and/or platelet GPIb alpha gene.

Adult↗