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S Hayakawa

Publications and source records attributed to S Hayakawa.

At least 55 records · Page 3Linked to original sources
PubMed2000

Expression of functional chemokine receptors of human placental cells.

PROBLEM: Chemokine receptors of placental trophoblasts possibly act as co-receptors or alternative receptors of maternal fetal infection by HIV. To clarify their possible expression and the physiological roles of chemokines on human placentae, we studied chemokine chemokine receptor expression and the effects of exogenous chemokines on choriocarcinoma cell lines. MATERIALS AND METHODS: Placental samples were obtained from 13 placentae of various gestational ages. Villous tissue was mechanically dissected from samples. Trophoblasts were enriched by anti-human chorionic gonadotropin (hCG)-coated magnetic beads. Human choriocarcinoma cell lines (JAR, BeWo, JEG-3) were maintained in RPMI 1640 media supplemented with 10% FCS. Expression of chemokine receptors was studied by RT-PCR. The effects of MIP-1alpha, RANTES, MCP-1 on hCG production were estimated by EIA. Effects of chemokines on proliferation of choriocarcinoma cell lines were examined by MTT assay. RESULTS: We observed mRNA expression of CCR-1, 2, 3, 4, 5 and CXCR-1, 2, 4 in 1st trimester placental villi, CCR-I, 2, 4 and CXCR-1, 2. 4 in 2nd trimester placental villi, CCR-1, 2, 4 and CXCR-4 in 3rd trimester placental villi. Using MACS enriched trophoblasts, we observed identical results. A choriocarcinoma cell line BeWo expressed CCR-1, 3, 4 and CXCR-1, 2, 4 while JEG-3 and JAR expressed CCR-1, 3, 4, 5 and CXCR-1, 2, 4. Expression of the CCR-5 and CXCR-4 protein in choriocarcinoma cell lines and MACS-enriched trophoblats were confirmed by flow cytometry. Chemokine MCP-3, MIP-1alpha, RANTES mRNA were expressed by the 1st, 2nd and 3rd trimester placental samples and the three choriocarcinoma cell lines examined. MCP-1 was expressed by 1st and 2nd trimester placental villi. Administration of chemokines up-regulated proliferation (10(-1) - 10 ng/mL) and hCG production (10(-1) - 10(-2)ng/ mL) of the three choriocarcinoma cell lines examined. CONCLUSIONS: Our results suggest possible roles of chemokines/chemokine receptors on placental physiology and their involvement in HIV transmission as alternative receptors.

Chemokines↗
PubMed2000

Electrophoretic and immunochemical characterization of allergenic proteins in buckwheat.

BACKGROUND: Buckwheat allergies are not common, however, it is considered to be a very potent allergen. Ingestion of small amounts has been found to produce anaphylactic reactions, particularly in children. Identification and characterization of the major allergen(s) in buckwheat are currently underway, however, there are some discrepancies in the findings. METHODS: Identification of the major allergen(s) was determined through Western blotting using buckwheat-allergic patients' sera. Once the allergenic proteins were identified, they were purified, their IgE-binding activity assessed through an indirect ELISA and the N-terminal amino acid sequence completed. To assess the stability of the IgE-binding epitopes, protein fractions were exposed to various treatments and assayed using an indirect ELISA. Lastly, the presence of anti-buckwheat IgG in the patients' sera was analyzed through Western blotting and ELISA. RESULTS: IgE binding was detected to proteins with molecular masses of approximately 14 and 18 kDa. N-terminal sequencing was completed and found to share some homology with rice proteins associated with rice allergies and cross-allergenicity with buckwheat proteins. When the water-soluble protein fraction was heated, exposed to acidic and alkaline conditions and fully denatured, IgE-binding activity was reduced. When the fraction was partially denatured through urea, IgE-binding activity increased. Furthermore, IgG-binding activity was detected with proteins only above the 20 kDa region. CONCLUSIONS: Proteins with molecular masses around 14 and 18 kDa were identified as the major allergenic proteins in the buckwheat-allergic patients' sera tested in this study. Results also indicate that these two proteins possess IgE-binding capability.

Adolescent↗
PubMed2000

Characterization of the nuclear localization signal in the DNA helicase responsible for Bloom syndrome.

Bloom syndrome (BS) is a rare genetic disorder characterized by small body size, photosensitivity, immunodeficiency and a high predisposition to various types of cancer. BLM was identified as the causative gene for BS. The BLM protein is homologous to DNA helicase and has two basic amino acid clusters in its C-terminal region. Previously, we reported that the distal arm of these basic amino acids clusters in the BLM protein functioned as the nuclear localization signal (NLS) of the protein. In this study, we generated plasmid constructs for expression of enhanced green fluorescent protein (EGFP) fused with various BLM protein variants having a mutation with deletions or substitutions in the basic amino acid and analyzed the subcellular localization of the expressed proteins. The EGFP-fused protein containing the basic amino acid cluster region proximal to the C-terminus of BLM helicase was localized exclusively in the nucleus. However, the EGFP-BLM proteins that lacked either Arg1344 or Lys1346 distributed in both the cytoplasm and the nucleus equally. Deletion of Arg1347 also resulted in localization in both the nucleus and cytoplasm, and substitution of Arg1344, Lys1346, Arg1347 or Arg1348 with non-basic amino acids reduced the nuclear localization of BLM protein. Mouse BLM protein which also migrate to the nucleus has two basic amino acid clusters in the C-terminus and the basic amino acids (Lys1346-Pro1347-Lys1348-Arg1349-Arg1350) proximal to the C-terminus are conserved between mouse and human. These findings suggest that the Arg1344-Ser1345-Lys1346-Arg1347 sequence at the C-terminus of the human BLM protein is essential for nuclear localization of this protein.

Adenosine Triphosphatases↗
PubMed2000

[Shuddering attacks in four children].

Shuddering attacks (SA), an uncommon benign disorder occurring during infancy or early childhood, should be distinguished from epileptic seizures. The attacks are shivering movements occurring daily for several seconds without impairment of consciousness. SA are regarded as an early premature manifestation of essential tremor (ET), and the provoking mechanism is the same between them. There are case reports of SA, but none from Japan. We studied the pathophysiology of SA in four children aged between 8 and 14 months using a video-EEG monitoring system. In one patient, the shuddering movements, as indicated by contaminating electromyogram during electroencephalography, was almost as frequent as that of ET. SA decreased in frequency or disappeared in all our patients. One of them showed immature brain development on MRI and had relatives with epilepsy. Another showed flattened sella turcica. Although previous reports suggest that SAs are benign and require no investigation, children with SA could have borderline problems related to the development of the nervous system.

Brain↗
PubMed2000

Free-flow isotachophoresis under micro-gravity.

When free flow electrophoresis (FFE) is applied to the separation and purification process under microgravity, higher separability is expected than that under usual 1 G environment, because sedimentation of samples and heat convection can be neglected. Although FFE under micro-gravity is a very important technique for efficient separation of macromolecules because of the above merits, FFE unit (FFEU) should be more sophisticated to give stable operation, high separability, high through-put and high separation efficiency. In this study, fundamental research to achieve FFE with such high performance was done by using a commercial FFEU. The research contains (1) the quantitative study on the separation mode of FFE and separation efficiency, (2) the feasibility analysis of free-flow bidirectional isotachophoresis (FFBITP) which enables separation of cations anions simultaneously by isotachophoresis (ITP) and zone electrophoresis (ZE), (3) the optimization of hardware factors such as thickness of the separation chamber which may cause deterioration of separation due to heat convection, and (4) the analysis of hardware factors depending on the long-time operation. The ultimate goal of this study is to obtain fundamental data for the development of FFE for the international space station. In this paper, the experimental results obtained in a reduced-gravity aircraft was mainly.

Electrophoresis↗
PubMed1999

Urine as another potential source for template DNA in polymerase chain reaction (PCR).

This technical note examines the potential for preparing template DNA in polymerase chain reactions (PCR) from urine in Japanese macaques (Macaca fuscata). Microsatellite band patterns from urine samples showed close agreement with those of blood and fecal samples, and only a few hundred microl of urine yielded a template DNA for PCR. This research will increase the opportunity for scientists to examine the genetic backgrounds of their target animals by using non-invasive sample collection in the wild.

Animals↗
PubMed1999

Effects of long-term cryopreservation on hematopoietic progenitor cells in umbilical cord blood.

There is considerable interest in developing banks of frozen umbilical cord blood cells for transplants but it is uncertain how long frozen cells survive. Our objective was to determine the recovery of frozen umbilical cord blood cells. We quantitated recovery of hematopoietic progenitor cells (CFU-GM, BFU-E, and CFU-GEMM) from frozen umbilical cord blood cells stored for up to 12 years. Decay rates of CFU-GM, BFU-E and CFU-GEMM (d, expressed as percent of viable cells recovered (95% confidence interval) were 0.9930 (0.9889-0.9970), 0.9840 (0.9769-0.9911) and 0.9817 (0.9707-0.9927). Time-dependent recoveries, calculated by the formula d(k), (k = frozen storage interval in years) were >90% at 10 years. We conclude that frozen cord blood cells can be stored safely for prolonged intervals without substantial loss in hematopoietic progenitor cells.

Cryopreservation↗
PubMed1999

Interleukin-12 augments cytolytic activity of peripheral and decidual lymphocytes against choriocarcinoma cell lines and primary culture human placental trophoblasts.

PROBLEM: Human trophoblasts are tolerant to the maternal immune system, but susceptible to interleukin (IL)-2-activated lymphocytes. IL-12 is also a key cytokine in the induction of cytotoxic responses. We administered IL-12 to peripheral blood lymphocytes (PBLs) and to decidual lymphocytes (DLs) and studied resulting cytotoxicity against trophoblasts. METHOD OF STUDY: PBLs and DLs were stimulated with rIL-2 and/or rIL-12 for 48 hr in vitro. Cytotoxicity against the choriocarcinoma cell line JEG-3, JAR, and primary culture trophoblasts were examined by LDH release assay. The proliferative response was estimated by MTT assay. Expression of cytotoxic factors was studied by reverse transcriptase-polymerase chain reaction (RT-PCR). RESULTS: Whereas IL-12 alone produced a modest enhancement in cytotoxicity of PBLs and DLs, the combination of IL-2 and IL-12 was most effective in trophoblast cell lysis. IL-12 enhanced the mRNA expression of T-cell specific serine protease (TSP, granzyme B) and FasL in DLs, but the expression of perforin was unchanged. Expression of these cytotoxic factors in PBLs was up-regulated by IL-12. CONCLUSION: Our findings indicate critical roles of IL-12 in the activation of maternal lymphocytes, which could possibly result in pregnancy failure syndromes.

Adult↗
PubMed1999

Molecular forms of serum pancreatic stone protein in acute pancreatitis.

CONCLUSION: Elevation of serum pancreatic stone protein-(PSP) S1 suggests activation of trypsinogen in the pancreas. This information would prompt the start of intensive treatment and may improve prognosis of acute pancreatitis (AP). BACKGROUND: PSP exists in two molecular forms, PSP-S2-5 and PSP-S1. PSP-S1 is produced by enzyme cleavage of PSP-S2-5 by trypsin. Total serum PSP rose in AP, but little is known about its molecular forms. In this study, we characterized the molecular forms of serum PSP in AP. METHODS: Sera were taken from 8 patients with severe acute pancreatitis (sAP) and from 11 patients with mild acute pancreatitis (mAP). Serum PSP was characterized by high-performance liquid chromatography (HPLC) followed by the specific enzyme immunoassay (EIA). RESULTS: The total serum PSP in sAP was higher than in mAP, but the difference was not significant. The PSP-S1 was detected in serum in all (7/7) patients in sAP and in 72% (8/11) of patients in mAP. Serum level of PSP-S1 was significantly higher in sAP than that in mAP (p < 0.05), and the cutoff value to distinguish the two groups was 30 ng/mL. Serum PSP-S1 did not show significant correlation with total PSP, immunoreactive trypsin, or C-reactive protein.

Acute Disease↗
PubMed1999

[A case report of male alcoholics treated the left replacement prosthesis on account of the idiopathic avascular necrosis of the left femoral head].

Idiopathic necrosis of the femoral head is already described associated with alcoholism. However, it is unusual to meet alcoholic patient with idiopathic necrosis of the femoral head in psychiatric hospital. In this report, we describe about the psychiatric treatment of an alcoholic male patient who complicated idiopathic necrosis of the femoral head. He begun drinking a large amount of alcohol at the age of 20. After 32 years old, he repeated admission to psychiatric hospitals for the treatment against alcohol dependence. At the age of 35, he felt left hip pain. At 36 years old, the illness was diagnosed as idiopathic necrosis of the femoral head and osteotomy was performed. After the operation, he did not keep the direction to keep a rest and not to drink. At last, total replacement arthroplasty was undergone. All through the treatment, we supported the patient to participate in group therapy and Alcoholics Anonymous, and approached directively and supportively to gain an insight about problems of drinking. As a result, after the last operation he hoped psychiatric treatment of his own will and began to gain insight gradually about his own alcoholic problems. This case emphasizes the necessity of psychotherapeutic approach and treatment programs for alcohol dependence and its physical complications.

Adult↗
PubMed1999

[Mental and physical symptoms in alcoholics after alcohol withdrawal--comparing with involutional melancholia patients].

As a factor of recurrence of drinking in patients with alcoholic dependence, emotional disorders accompanied by alcohol dependence has been noted in many reports. Particularly, it is noted to be very likely that depression after abstinence is an incentive to re-start drinking. In this study, we investigated depressive feeling in aspects of psychiatric and physical subjective symptoms after abstinence in patients with alcohol dependence, and compared the symptoms with those in patients with involutional depression. On analysis of the major component of psychiatric subjective symptoms, a sense of alienation, emotional instability, anxiety, and aggressiveness were observed. In involutional depression, depressive feeling, somnipathy, anxiety, self accusation/sense of guilt, delusion of culpability were observed. On analysis of the major component of physical subjective symptoms, autonomic nervous symptoms accompanied by feebleness, hysterical neurosis-like autonomic nervous symptoms, reduced sexual libido, anorexia, hydrodipsia/sweating were observed. Similarly, in patients with involutional depression, hysterical neurosis-like autonomic nervous symptoms, anorexia, elevation of tonus, general malaise, and hydrodipsia were noted. Differences in status were emphasized in comparison between the two groups in both analyses. Unlike involutional depression that exhibits the current features of depression, patients with alcohol dependence showed a sense of alienation, emotional instability, anxiety, and aggressiveness, reflecting self-uncertainty and loss of self-respect. Drinking may be re-started to relieve or reduce tension and frustration in such conditions.

Alcoholism↗
PubMed1998

X-ray microprobe system for XRF analysis and spectroscopy at SPring-8 BL39XU.

An X-ray microprobe system for X-ray fluorescence (XRF) analysis and spectroscopy has been developed at SPring-8 BL39XU; it comprises an X-ray focusing or collimation system, energy-dispersive (ED) and wavelength-dispersive (WD) XRF spectrometers, and a sample-scanning system. The conventional ED spectrometer will be utilized for qualitative and quantitative trace-element analysis, and the WD spectrometer will be used both for trace-element analysis and XRF spectroscopy. A combination of monochromated undulator radiation and the WD spectrometer will enable resonant XRF spectroscopy using brilliant hard X-ray undulator radiation.

Journal Article↗
PubMed1998

Material analysis end-station of the Hyogo-ken beamline at SPring-8.

Plans to construct surface-analysis equipment which will be placed on beamline BL24XU of SPring-8 are presented. There are three experimental hutches in BL24XU, which are available simultaneously by using diamond monochromators as beam splitters. The purpose of the surface-analysis equipment is the simultaneous measurement of fluorescent and diffracted X-rays in grazing-incidence geometry. The instrument is equipped with a solid-state detector (SSD) and a flat position-sensitive proportional counter (PSPC) combined with analysing crystals for X-ray fluorescence (XRF) analysis. A curved PSPC and the goniometer that mounts the SSD used for XRF are also installed for X-ray diffraction. X-ray fluorescence holography and polarized X-ray emission spectroscopy modes are available, so three-dimensional images of atomic configurations and also the anisotropic structure of materials will be studied.

Journal Article↗
PubMed1998

Contrast-enhanced endoscopic ultrasonography in gallbladder diseases.

BACKGROUND: The purpose of this study was to investigate the usefulness of contrast-enhanced endoscopic ultrasonography in gallbladder diseases. METHODS: Subjects were 38 patients including 12 with adenocarcinoma, 2 adenosquamous carcinoma, 6 cholesterol polyp, 10 cholecystitis, and 8 adenomyomatosis. After endoscopic ultrasonography, sonicated albumin was intravenously injected and the enhanced effect on images of these lesions was determined. For malignancies we compared diagnostic accuracy (T factor, TNM classification) of endoscopic ultrasonography and contrast-enhanced endoscopic ultrasonography. Vascularity as shown by contrast-enhanced endoscopic ultrasonography and angiograms was compared. RESULTS: Enhancement was observed in 11 patients with adenocarcinoma but not of those with adenosquamous carcinoma or cholesterol polyp. Angiography provided hypervascular images for all cases of adenocarcinoma, but all other lesions were hypovascular. In one case of adenocarcinoma, 3 cases of adenomyomatosis, and 8 cases of cholecystitis, there was a discrepancy between contrast-enhanced endoscopic ultrasonography images and angiograms with regard to vascularity. The accuracy of depth of tumor invasion for endoscopic ultrasonography was 78.6% (11 of 14) versus 92.9% (13 of 14) for contrast-enhanced endoscopic ultrasonography. CONCLUSION: Contrast-enhanced endoscopic ultrasonography is useful in the diagnosis of gallbladder lesions.

Adenocarcinoma↗
PubMed1998

Ultrasonic implantation of calcium metasilicate glass particles into PMMA.

Polymer materials for clinical applications should be bioactive and have a bone-bonding ability. In order to provide poly(methyl methacrylate) (PMMA) with bioactivity, granules (<45 microm) of a bioactive glass 50CaO.50SiO2 (mol %) were implanted into PMMA: they were suspended together with a piece of PMMA in a 40 tetrahydrofuran-60 ethanol (vol %) solution and ultrasonically agitated. The granules of <10 microm in size were impregnated at approximately 40-20 microm depth below the substrate surface. Two types were detected on the PMMA surface: (a) a glass-granule layer on PMMA, and (b) an inner granule layer, a PMMA layer, and an outer granule layer on the PMMA. The bioactivity of the implanted PMMA substrates was examined in vitro with a simulated body fluid (Kokubo solution). Apatite was precipitated on all glass granules and the whole substrate surfaces within 1 d. After 4 h soaking in the Kokubo solution, aggregates of apatite particles appeared on the substrate surface, independently of those on the glass granules, and they grew and proliferated on the whole subtrate surface in 7 d. Silica gel islands on PMMA due to the silicate anions from the glass were considered to induce nucleation of the apatite particles.

Journal Article↗
PubMed1998

Expression of Pax5 gene in human haematopoietic cells and tissues: comparison with immunodeficient donors.

In mice, Pax5 gene is indispensable for B cell development. Pax5-deficient mice fail to produce mature B cells owing to complete arrest of B cell development at a precursor stage. However, the lineage and stage of human Pax5 gene expression have remained elusive. In this investigation expression of the human Pax5 gene was studied. Pax5 gene expression was detected in B cell lines but not in myeloma cell lines. CD19 expression was correlated with Pax5 gene expression. Adult spleen and bone marrow and fetal spleen and liver showed strong Pax5 gene expression, as did the corresponding mouse tissues, as reported previously. In common variable immunodeficiency (CVID) peripheral blood lymphocytes (PBL) with a decreased number of B cells, no Pax5 gene expression was detected. Some CVID PBL stimulated with IL-2, IL-10 and anti-CD40 monoclonal antibody, expressed the Pax5 gene. Defect of Pax5 gene expression in CVID may be caused by regulatory T cell disorder.

Adolescent↗