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Biomedical subjects

M Eguchi

Publications and source records attributed to M Eguchi.

At least 91 records · Page 5Linked to original sources
PubMed1997

Determination of lead and cadmium in food and blood by inductively coupled plasma mass spectrometry: a comparison with graphite furnace atomic absorption spectrometry.

To compare inductively coupled plasma mass spectrometry (ICP-MS) and graphite furnace atomic absorption spectometry (GF-AAS) as the method for determining lead and cadmium in the human diet and blood, 418 diet homogenate samples and the same number of blood samples were collected from Chinese and Japanese women and were analyzed by the two methods. The results showed that our ICP-MS method is precise and accurate, being comparable to the GF-AAS method established previously. The ICP-MS method is simple and fast spending only one-tenth of the time necessary for GF-AAS and allows simultaneous analyses of lead and cadmium with low detection limits. When applied to actual sample analysis, however, ICP-MS results tend to be 10-20% lower than GF-AAS results in the analysis of lead in the diet and blood and cadmium in blood. This is possibly due to some interference in ICP-MS and matrix of samples. As the ICP-MS results could be mathematically corrected to be equivalent to the GF-AAS results, we conclude that this ICP-MS method can be used as a routine analytical method for the determination of lead and cadmium in human diet and blood samples.

Blood Chemical Analysis↗
PubMed1997

In vitro development of erythroid and megakaryocytic cells from a UT-7 subline, UT-7/GM.

UT-7 is a human megakaryoblastic leukemia cell line with absolute dependence on interleukin-3, granulocyte-macrophage colony-stimulating factor (GM-CSF), or erythropoietin (EPO) for growth and survival. We isolated a novel subline, UT-7/GM after long-term culture of UT-7 with GM-CSF. The hemoglobin concentration and gamma-globin and EPO-receptor mRNA levels were significantly higher in EPO-treated UT-7/GM cells than in untreated cells. In contrast, the platelet factor 4 and glycoprotein IIb mRNA levels were much higher in thrombopoietin (TPO)-treated UT-7/GM cells than in untreated cells. Some TPO-treated cells had morphologically mature megakaryocytic characteristics such as a developed demarcation membrane in the cytoplasm and multilobular nuclei. These findings indicate that UT-7/GM is a bipotential cell line that can be induced to differentiate into erythroid and megakaryocytic lineages by EPO and TPO, respectively. Moreover, a minority of UT-7/GM cells acquired a high hemoglobin concentration by treatment with TPO, suggesting that TPO in part induced the erythroid differentiation of the UT-7/GM cells. Interestingly, GM-CSF inhibited the EPO- or TPO-induced erythroid differentiation and the TPO-induced megakaryocytic differentiation of UT-7/GM cells. These results support the hypothesis that cytokines influence the programming of gene expression required for lineage commitment or differentiation.

Cell Differentiation↗
PubMed1997

DNA damage-associated dysregulation of the cell cycle and apoptosis control in cells with germ-line p53 mutation.

Lymphoblastoid cell lines (LCLs) with heterozygous p53 mutations at residues 286A, 133R, 282W, 132E, and 213ter were established from five independent Li-Fraumeni syndrome families. When cell cycle regulation in response to gamma-irradiation was studied, these LCLs showed an abnormal G1 checkpoint associated with defective inhibition of cyclin E/cyclin-dependent kinase 2 activity in all cases except for 282W LCL, which showed a normal G1 checkpoint. On the other hand, the control of S-phase-G2 as determined by cyclin A/cyclin-dependent kinase 2 activity was defective in all these LCLs. The mitotic checkpoint was also defective in the two LCLs analyzed as either competent or incompetent for G1 arrest. When radiation-induced apoptosis, which requires wild-type p53 function under optimal conditions, was studied, all of these LCLs showed significant failure compared to normal LCLs. These findings indicate that although p53-dependent transactivation and G1-S-phase cell cycle control are variably dysregulated, the induction of apoptosis and control of the cell cycle at S-phase-G2 and the mitotic checkpoint in response to DNA-damaging agents are consistently dysregulated in heterozygous mutant LCLs. This suggests that these dysfunctions underlie, at least in part, the susceptibility of Li-Fraumeni syndrome families to cancer. Furthermore, the approach presented is a potentially useful method for studying individual carriers of different germ-line p53 mutations and different biological features.

Adolescent↗
PubMed1997

Frequent jumping translocations of chromosomal segments involving the ABL oncogene alone or in combination with CD3-MLL genes in secondary leukemias.

Seven secondary leukemia patients were treated for solid tumors or malignant lymphoma with anticancer drugs or radiation. We studied bone marrow samples from these patients by fluorescence in situ hybridization (FISH). Of the seven patients, three had increased signals for the ABL oncogene (9q34) on interphase nuclei and at metaphase. One of the three patients also had four signals for the CD3 (MLL) region (11q23). Whole painting probes revealed that these chromosomal regions were translocated onto structurally abnormal chromosomes, resulting in partial tri-, tetra- or penta-somy of these regions. We called this type of translocation "segmental jumping translocation (SJT)." SJT of the ABL oncogene was not detected in samples from 15 patients with de novo acute myelocytic leukemia (AML), 12 with myelodysplastic syndrome (MDS), or 20 with chronic myelocytic leukemia (CML) at the chronic phase. Furthermore, monosomy 7 was also found in the patients with the gene amplification. These results indicate that SJT of ABL and/or CD3 (MLL) genes is associated with the leukemogenesis of secondary leukemia. The SJT may be one mechanism of gene amplification.

Aged↗
PubMed1997

Application of fluorescence in situ hybridization to detect residual leukemic cells with 9;22 and 15;17 translocations.

We performed fluorescence in situ hybridization (FISH) upon 9;22 and 15;17 translocation-positive bone marrow cells to monitor the clinical course of 46 patients with chronic myelocytic leukemia (CML) and nine with acute promyelocytic leukemia (AML M3) who received chemotherapy and/or bone marrow transplantation (BMT). M-BCR-ABL and PML-RAR alpha probes were used to detect translocations of t(9;22) and t(15;17), respectively. Signals from CML patients treated with interferon (17 patients) or BMT (29 patients) were 0.5-15% positive for the 9;22 translocation. Among nine M3 patients who received extensive chemotherapy or BMT, 1-5% were positive for the 15;17 translocation. A highly sensitive FISH procedure using both translocation probes and a whole chromosome Y probe was established and applied to eight sex-mismatched BMT patients (seven CML and one AML M3), in which 0.1-0.6% of signals positive for the specific translocations were detected. These results suggested that interphase FISH is powerful enough to identify minor cell populations of 9;22 or 15;17 translocations after therapy, as well as to detect specific chromosome abnormalities at diagnosis.

Bone Marrow↗
PubMed1997

Alterations of p16 and p15 genes in acute leukemia with MLL gene rearrangements and their correlation with clinical features.

p16 and p15 genes are putative tumor suppressor genes located on chromosome 9p21. In acute leukemias, alterations of p16 and p15 genes have been reported to occur exclusively in lymphoid lineage. We analyzed alterations of p16 and p15 genes in 46 acute leukemias with MLL gene rearrangements by Southern blot analysis, and investigated the association with clinical characteristics. We identified homozygous deletion of p16 and p15 genes in five (19%) of 27 acute lymphoblastic leukemias (ALLs) and in two (11%) of 19 acute myeloid leukemias (AMLs). Patients with homozygous deletion of p16 and p15 genes showed higher average leukocyte counts (343 x 10(9)/l vs 271 x 10(9)/l) and lower estimated 2-year survival rates than those with normal p16 and p15 genes (14.3 vs 30.7%), although the differences were not statistically significant. In addition, we investigated mutation of p16 gene by polymerase chain reaction single strand conformation polymorphism (PCR-SSCP) in 31 patients, but no mutation was found in the patients tested. Our results suggest that alterations of p16 and p15 genes are involved in a subset of acute leukemias with MLL gene rearrangement not only of lymphoid but also of myeloid phenotype. Homozygous deletion of p16 and p15 genes may be a possible adverse prognostic factor, although further analysis would be needed to confirm it.

Adolescent↗
PubMed1997

Detection of residual host cells in sex-mismatched bone marrow transplantation in various hematological diseases by fluorescence in situ hybridization.

Thirty-eight sex-mismatched bone marrow transplantation patients with various hematological diseases were followed-up using fluorescence in situ hybridization. Probes specific for various translocations, the X chromosome (DXZ1) and the whole Y chromosome (WCP Y), were used to assess successful engraftment and residual host cells. The combination of translocation and WCP Y probes enabled the identification of host and donor cells in addition to the identification of malignant vs. normal cells in the transplant recipient. Fifteen patients were sequentially followed up. The results obtained using the combination of translocation plus WCP Y probes were more reliable than those with DXZ1 plus WCP Y probes, or the translocation probe alone, especially when the percentage of residual leukemic cells detected by the translocation probe alone was around the cut-off level.

Bone Marrow Transplantation↗
PubMed1997

Renal effects of alcohol withdrawal in five-week alcohol-treated rats.

OBJECTIVE: The effects of alcohol withdrawal on renal function following renal ischemia was examined in rats fed a liquid containing ethanol for 5-week alcohol treatment. METHOD: For alcohol-treated rats, animals were fed with an ethanol-containing diet for 5 weeks. In withdrawal studies, the alcoholic diet was replaced by a regular diet following 5-week alcohol treatment. Renal ischemia was induced by clamping the renal artery for 20 minutes and renal function was evaluated 24 hours later. RESULTS: Alcohol ingestion for 5 weeks did not alter the renal function in the absence of renal ischemia. Mean (+/- SD) glomerular filtration rate (GFR) and renal plasma flow rate (RPFR) measured 24 hours after ischemia in control rats were 430 +/- 29.6 microliters/min/g/kidney weight (gKW) and 1.4 +/- 0.17ml/min/gKW, whereas in alcohol-treated rats, they were 117.2 +/- 35.2 microliters/min/gKW and 0.31 +/- 0.12ml/min/gKW, which values were significantly lower than controls (p < .05). However, when alcohol was withdrawn for 1 week, the renal function of rats after ischemia was no different from that of control rats (GFR = 413.9 +/- 66.3 microliters/min/gKW and RPFR = 2.14 +/- 0.7 ml/min/gKW). As for renal histopathology, tubular damage was milder 1 week after alcohol withdrawal compared to that observed in rats fed the alcohol-containing diet for 5 weeks. CONCLUSIONS: The findings suggest renal damage induced in rats by exposure to alcohol for 5 weeks was reversed when alcohol was withdrawn for 1 week before renal ischemia.

Alcohol Withdrawal Delirium↗
PubMed1997

Molecular analysis of minimally differentiated acute myeloid leukemia with chromosome 16 inversion.

We report a 3-year-old girl with minimally differentiated acute myeloid leukemia and chromosome 16 inversion (inv 16). Inv 16 is generally associated with acute myelomonocytic leukemia with dysplastic eosinophils in the bone marrow (AML-M4Eo). Recently, molecular analysis showed that a fusion gene is generated by this inversion between the CBFB gene on the q arm and the MYH11 gene on the p arm. Using reverse transcriptase-polymerase chain reaction analysis, we tried to detect CBFB/MYH11 chimeric mRNA in blasts from our patients, however, were unable to detect any chimeric mRNA in the blasts: The absence of CBFB/MYH11 transcripts in this case suggests that rare chimeric products might be formed as a result of inv 16 that could not be detected by the primer sets used in this study. Another possibility is that different genes are rearranged on the chromosome 16 with the inv 16. More detailed molecular analysis of this case might be necessary in order to elucidate these possibility. Analyzing leukemias with inv 16 which do not have a typical CBFB/MYH11 chimeric mRNA might lead to understanding an alternative pathogenesis for acute leukemia with inv 16.

Acute Disease↗
PubMed1997

Characterization of acute leukemia with t(4;12).

Acute leukemia with t(4;12)(q11-13;p12-13) is rare but has unique characteristics. The incidence of t(4;12) in acute leukemias was about 0.6% in our laboratory. Twelve patients with acute leukemia with t(4;12) have been reported until now. They included eight acute myeloid (AML: M0 2, M1 3, M2 1, M4 1, and M7 1), three acute lymphoblastic (ALL: L1) and one acute unclassified leukemia (AUL). There were some differences between adults and children with t(4;12). The eight adult patients included seven with AML and one with AUL, two of whom had a history of exposure to mutagenic agents and/or genotoxic therapy. Three patients had the CD7+ HLA-DR+ CD13+ CD34+ c-kit+ phenotype, suggesting that the leukemic cells were of stem cell origin. Four children expressed the B lymphoid phenotype (HLA-DR+ CD10+ CD19+) although one had myeloperoxidase positivity. It was difficult for adult patients to achieve complete remission with the usual therapy regimen, whereas children with t(4;12) seemed to be easier to treat. Rearrangement of the TEL gene located on the short arm of chromosome 12 (12p13), was investigated in two adult patients. FISH analysis using the YAC probe that covers the TEL gene region, revealed split signals in these patients, suggesting a break inside or near the TEL gene. The t(4;12) abnormality is associated with unique characteristics of acute leukemia namely stem cell or secondary AML in adults, and B lymphoid leukemia in children.

Acute Disease↗
PubMed1997

Chloroquine induces basophilic differentiation of HL-60 cells.

Many agents have been known to induce the differentiation of HL-60 cells. However, only a small number of reports on the basophilic differentiation of this cell line are known. In this study we show that the exposure of HL-60 cells to chloroquine induces to differentiate into basophils. This chloroquine-induced change suggests that the increase in intracellular pH and the upregulation of p21 with subsequent downregulation of cdc2 kinase are triggers for basophilic differentiation of this cell line.

Basophils↗
PubMed1997

[Two clinical case of spontaneous hemopneumothorax caused by aberrant vessel].

Spontaneous hemopneumothorax is a rare disease and intrathoracic bleeding reportedly occurs in the detached region of adhesive parietal pleura, aberrant vessel and cystic wall. We experienced two cases of bleeding most likely from the aberrant vessel. One patient was a 25-year-old male who had severe chest pain with dyspnea for four days. Chest X-ray revealed left pneumothorax and mediastinal shift to the right. Approximately 1500 ml of blood was aspirated from the left thoracic cavity. Since bleeding continued, emergency thoracotomy was performed. A restiform structure was noted in the bulla at the apex of the lung and the stump of the structure was considered as the source of bleeding. The other patient was a 29-year-old male who underwent emergency operation 16 hours after the massive bleeding amounting to 1800 ml. At the thoracotomy, a ruptured bulla at the apex of the collapsed lung with restiform structure was encountered. The bleeding point in the stump of the structure was ligated and the ruptured bulla was resected. In the histological study of these patients, an aberrant blood vessel was revealed in the restiform structure, which suggests the etiology of the bleeding. Their postoperative course was uneventful and had no symptom at the discharge. In the management of spontaneous hemopneumothorax, early thoracotomy should be the first consideration taking into account the massive bleeding from the aberrant vessel as in the cases.

Adult↗
PubMed1996

Separation of naphthalene and flavone derivatives by micellar electrokinetic chromatography with double- and triple-chain surfactants.

Three surfactants, p-bis(2-dodecyloxymethyl-3-oxa-6-sodiosulfonatohexyloxy)benz ene (BDSB) having two sulfonate groups and two lipophilic chains, disodium 10-dodecanoyl-5,15-bis(dodecyloxymethyl)-10-aza-4,7,13,16-tetra oxa-1,19-nonadecanedisulfonate (DDBTN) having two sulfonate groups and three lipophilic chains and disodium 4,11-bis(dodecyloxymethyl)-3,6,9,12-tetraoxa-1,14-tetrade canedionate (DBTT) having two carboxylate groups and two lipophilic chains, were used in micellar electrokinetic chromatography (MEKC). Eight naphthalene derivatives were baseline separated at 10 mM BDSB or 5 mM DBTT, and five flavone derivatives at 5 mM BDSB, DDBTN or DBTT. The elution order of the naphthalene derivatives in MEKC with BDSB was identical with that with DDBTN. However, this elution order was different from that found with DBTT. In the case of the flavone derivatives, BDSB, DDBTN and DBTT produced the identical elution order. These double- and triple-chain surfactants exhibited different selectivity when compared with widely used sodium dodecyl sulfate.

Electrophoresis, Capillary↗
PubMed1996

Establishment and characterization of the thrombopoietin-dependent megakaryocytic cell line, UT-7/TPO.

UT-7 is a human megakaryoblastic leukemia cell line with absolute dependence on interleukin-3, granulocyte-macrophage colony-stimulating factor, or erythropoietin (EPO) for growth and survival. We investigated the effect of thrombopoietin (TPO), the ligand for the receptor encoded by c-mpl proto-oncogene, on the proliferation and differentiation of UT-7 and its sublines. We found that UT-7/GM, which is a subline of UT-7, but neither UT-7 nor UT-7/EPO, can proliferate in response to TPO. The subline, UT-7/TPO, was established from UT-7/GM by culture at lower concentrations of TPO. UT-7/TPO cells had morphologically mature megakaryocytic characteristics such as developed demarcation membrane in the cytoplasm and multinucleated appearance. This was also confirmed by the high expression of platelet factor-4 and glycoprotein IIb at the mRNA levels and by the high level of DNA content. UT-7/TPO can be maintained by TPO alone, with a doubling time of 24 hours in log growth phase. In the absence of TPO, the majority of the cells died within a few days. Thus, UT-7/TPO has an absolute dependence on TPO for growth and survival and has mature megakaryocytic features. The mRNA for c-mpl was detected in UT-7/TPO and, to a lesser degree, in UT-7/GM. The mRNA level of NF- E2 p45, reported to be an erythroid-specific transcription factor, was upregulated in UT-7/TPO, whereas it was down-regulated in the erythroid subline, UT-7/EPO. There were no significant differences in GATA-1 and GATA-2 mRNA levels among UT-7 and its sublines. Not only EPO but also TPO induced the tyrosine phosphorylation of JAK2 tyrosine kinase and STAT5-related protein. These findings indicate that UT-7/TPO would be a useful model with which to analyze the gene regulation of megakaryocytic maturation-associated proteins and to study the specific actions of TPO.

Cell Differentiation↗
PubMed1996

Establishment of a myeloid leukaemia cell line (Kasumi-4) with t(9;22;11)(q34;q11;q13), inv(3)(q21q26) and the EVI1 gene activation from a patient with chronic myelogenous leukaemia in blast crisis.

A novel human leukaemia cell line (Kasumi-4) was established from the peripheral blood of a 6-year-old girl suffering from chronic myelogenous leukaemia (CML) in blast crisis. The Kasumi-4 cells had the following characteristic features: undifferentiated blasts which were positive from CD34, CD33 and CD13 surface markers, but negative for myeloperoxidase platelet peroxidase, CD36, CD41 and CD42; chromosome abnormalities of t(9;22;11) (q34;q11;q13), inv(3)(q21q26); and elevated expression of EVI1 gene which is located at chromosome band 3q26. Megakaryocytic maturation was not observed in the liquid culture following the addition of TPA, IL3, IL-6 or GM-CSF, b2-a2 type of BCR-ABL chimaeric messenger RNA was detected by RT-PCR analysis. This the first leukaemia cell line with a three-way translocation containing the the Ph chromosome and the second cell line with an inv(3)(q21q26). This cell line appears to be useful for studying the mechanisms of leukaemogenesis involving these chromosomal abnormalities and related oncogenes.

Base Sequence↗