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N Nara

Publications and source records attributed to N Nara.

At least 19 recordsLinked to original sources
PubMed2001

[Molecular diagnostic tests in hematologic diseases].

Molecular diagnostic tests are widely performed in managing hematologic malignancies such as leukemia and lymphoma. In this article, we review the present application and problems of the tests. Karyotyping is performed at diagnosis of all kinds of hematologic malignancies. This method needs dividing cells as samples and skilled experts. Fluorescence in situ hybridization(FISH) analysis using cells in interphase is performed, for example, to monitor the effect of interferon on chronic myelogenous leukemia patients. The weak point of this method is that approximately 2% of false-positive cells are inevitable. Southern blot method is used for clonal analysis in some disease, for example, adult T-cell leukemia/lymphoma. Polymerase chain reaction(PCR) method using genomic DNA is performed for limited types of diseases such as lymphoma with bcl-2/IgH fusion gene. Reverse transcription(RT)-PCR method can detect fusion gene transcripts with high sensitivity. This method is useful for detecting minimal residual diseases after chemotherapy or bone marrow transplantation. To perform quantitative analysis, real-time PCR or competitive PCR must be done. In the near future, new technology such as gene expression profiling analysis using DNA microarrays or spectral karyotyping(SKY) method will be used in clinical practice.

Blotting, Southern↗
PubMed2001

[DNA diagnosis in hematological malignancies].

The recent advances in molecular biology and gene engineering have greatly contributed to the diagnosis and treatment of hematopoietic malignancies, such as leukemia and malignant lymphoma. It is now possible to precisely determine the clonal origin of malignant cells, the subtype of leukemia or lymphoma, and the clinical prognosis in each patient. Furthermore, minimal residual malignant cells in leukemia or lymphoma patients after achieving complete remission can be detected by DNA analysis. Based on these analyses, theoretically treatment can be tailored for each patient. We discuss in the present paper the usefulness of DNA or gene analyses in the clinical laboratory for hematopoietic malignancies.

DNA↗
PubMed2000

Prostaglandin E1 reduces myocardial reperfusion injury by inhibiting proinflammatory cytokines production during cardiac surgery.

OBJECTIVE: To determine the influence of prostaglandin E1 (PGE1) on the cytokine balance and myocardial protection during cardiac surgery. DESIGN: Prospective, randomized, nonblinded study. SETTING: University hospital. PATIENTS: A total of 19 patients on cardiopulmonary bypass undergoing cardiac surgery. INTERVENTIONS: According to randomized sequence, the patients received PGE1 (0.02 approximately 0.05 microg x kg(-1) x min(-1)) from the beginning of surgery to the end of study (PGE1 group, n = 11) or nothing (control group, n = 8). MEASUREMENTS AND MAIN RESULTS: Interleukin (IL)-6, IL-8, IL-10, IL-1 receptor antagonist (IL-1ra), soluble tumor necrosis factor receptor I (sTNF RI), and soluble tumor necrosis factor receptor II (sTNF RII) were measured by enzyme-linked immunosorbent assays. Troponin-T and isoenzyme of creatine kinase with muscle and brain subunits (CK-MB) were measured by enzyme immunoassay and ultraviolet absorption spectrophotometry method, respectively. Serum IL-6 and IL-8 concentrations in both groups increased significantly from 60 mins after declamping the aorta compared with preoperative value (p < .001), However, the increases were greater in the control group than in the PGE1 group (p < .01). Serum IL-10, IL-1ra, sTNF RI, and sTNF RII concentrations increased significantly from 60 mins after declamping the aorta compared with preoperative values in two groups (p < .001, respectively). There were no differences between the two groups. Serum troponin T and CK-MB concentrations increased significantly in the two groups from 60 mins after declamping the aorta (p < .001), but these increases were greater in the control group than in the PGE1 group (p < .01). IL-6 and IL-8 levels correlated with CK-MB concentration (r2 = 0.49, r2 = 0.36; p > .001 respectively). CONCLUSIONS: PGE1 suppressed the production of IL-6 and IL-8 but not IL-10, IL-1ra, sTNF RI, or sTNF RII. The change in the balance between pro-and anti-inflammatory cytokines may be one of the most important cytoprotective mechanisms of PGE1.

Aged↗
PubMed2000

Polymerase chain reaction detection of rearranged immunoglobulin heavy chain DNA in plasma samples is useful in the diagnosis of B-cell lymphoma.

Using DNA extracted from plasma samples of B-cell non-Hodgkin's lymphoma (B-NHL) patients, we attempted to detect the monoclonal rearrangement of immunoglobulin heavy chain gene by amplifying complementarity-determining region 3 (CDR3) by semi-nested polymerase chain reaction (PCR) method (plasma PCR). In 19 of 37 (51%) cases, clonal DNA was detected. With the same PCR method using DNA extracted from peripheral blood mononuclear cells, clonal DNA was detected in 8 of the 37 cases (22%). These 8 were in advanced stages with bone marrow (BM) invasion mostly. On the other hand, the 19 positive cases by plasma PCR included those in early stages without BM invasion or with normal soluble interleukin-2 receptor (sIL-2R) and lactate dehydrogenase (LDH) values. In 15 healthy volunteers, plasma PCR showed no clonal DNA. In cases in which tumor biopsy was difficult to perform, plasma PCR was helpful for determining whether or not the tumor was B-NHL. Plasma PCR is simple and has high specificity, although its sensitivity is insufficient.

Aged↗
PubMed1999

Establishment of a double Philadelphia chromosome-positive acute lymphoblastic leukemia-derived cell line, TMD5: effects of cytokines and differentiation inducers on growth of the cells.

A double Philadelphia chromosome (Ph)-positive leukemia cell line with common-B cell phenotype, designated TMD5, was established from the blast cells of a patient with double Ph-positive acute lymphoblastic leukemia. TMD5 cells expressed 190 kDa BCR/ABL chimeric protein and 145 kDa ABL protein. The cells proliferated without added growth factors. Autocrine growth mechanism was not recognized. The addition of growth factors such as G-CSF, GM-CSF, IL-3, IL-6, or Stem Cell Factor did not affect the growth. Herbimycin A suppressed the growth of TMD5 cells at the low concentration that did not affect Ph-negative cells. It suppressed tyrosine phosphorylation of intracellular proteins in TMD5 cells. Dexamethasone and dibutyryl cyclic AMP also suppressed the growth. They, however, did not affect the phosphorylation significantly. Neither all-trans retinoic acid nor interferon-alpha affected the growth. TMD5 cells, characterized minutely here and rare in that they have double Ph chromosomes, will be a useful tool for the study of Ph-positive leukemia.

Adult↗
PubMed1999

Priming with G-CSF effectively enhances low-dose Ara-C-induced in vivo apoptosis in myeloid leukemia cells.

We investigated the role of apoptosis in chemotherapy for hematologic malignancies. Twelve consecutive patients with acute myelogenous leukemia (AML) or refractory anemia with excess of blasts in transformation (RAEB-t) who were not tolerable for standard-dose chemotherapy were treated with CAG regimen (low-dose cytosine arabinoside [Ara-C] plus aclarubicin with concurrent administration of granulocyte colony-stimulating factor [G-CSF]). Bone marrow mononuclear cells obtained before the commencement of the chemotherapy were cultured with various concentrations (0-10(-5) M) of Ara-C in the presence or absence of 10 ng/mL of G-CSF, and the resultant cell proliferation/cytotoxicity was assayed. In all but one patient, half killing concentration (LC50) of Ara-C was significantly reduced in the presence of G-CSF (by 400- and 1.45-fold, median: 21-fold). Furthermore, LC(50) values in responders assayed in the presence of 10 ng/mL of G-CSF were significantly lower than those in nonresponders (p = 0.02). In vitro killing tests using a G-CSF-dependent leukemic cell line suggested that addition of G-CSF potentiates Ara-C-induced cytotoxicity through the mechanism of apoptosis. We thus assayed apoptosis in peripheral blood leukemic cells during CAG chemotherapy by flow cytometry using 7-amino-actinomycin D. Peak percentages of apoptosis in responders were significantly higher than those in nonresponders (p = 0.02). These results collectively suggest that apoptosis plays an important role for eradicating leukemic cells by CAG chemo-therapy.

Aged↗
PubMed1999

Influence of methylprednisolone on cytokine balance during cardiac surgery.

OBJECTIVE: To determine the influence of methylprednisolone on the cytokine balance during cardiac surgery. DESIGN: Prospective, randomized, nonblinded study. SETTING: University hospital. PATIENTS: Twenty-one patients on cardiopulmonary bypass undergoing aortocoronary bypass surgery. INTERVENTIONS: According to a randomized sequence, the patients either received methylprednisolone (30 mg/kg) [corrected] before cardiopulmonary bypass and before declamping of the aorta (MPS group, n = 11) or received nothing (control group, n = 10). MEASUREMENTS AND MAIN RESULTS: Serum proinflammatory cytokines (interleukin [IL]-8, IL-6) and anti-inflammatory cytokines (IL-10, IL-1ra) were measured by enzyme-linked immunosorbent assays. Serum IL-6 and IL-8 concentrations in the control group (15.2 +/- 4.1 and 14.1 +/- 1.9 pg/mL, preoperatively) increased to 242 +/- 70.1 and 97.3 +/- 18.3 pg/mL at 60 mins after declamping of the aorta (p < .01, p < .01, respectively). The increases were greater than those from 2.5 +/- 0.6 and 2.5 +/- 0.5 pg/mL to 109.5 +/- 29.0 and 33 +/- 4.1 pg/mL in the MPS group for IL-6 and IL-8, respectively. Serum IL-10 concentrations increased significantly 60 mins after declamping of the aorta compared with its preoperative value in the two groups (the control group, from 1.0 +/- 0 to 537.9 +/- 61.7 pg/mL; the MPS group, from 0.3 +/- 0.2 to 654.9 +/- 24 pg/mL [p < .01, p < .01, respectively]). No difference was found between the two groups. Similarly, serum IL-1ra concentrations in the two groups increased the preoperative value in the control group from 304 +/- 120 to 44,374 +/- 14,631 pg/mL and in the MPS group from 616.5 +/- 109.6 to 35,598 +/- 9,074 pg/mL at 60 mins after declamping of the aorta (p < .01, p < .01, respectively). There was no difference between the two groups. CONCLUSIONS: Methylprednisolone reduces the production of IL-6 and IL-8 but not that of IL-10 and IL-1ra. These results suggest that one of the mechanisms of the cytoprotective effect of methylprednisolone may be to make changes in the proinflammatory and anti-inflammatory cytokine balance.

Aged↗
PubMed1999

[DNA diagnosis of hematopoietic malignancies].

The recent advances in molecular biology and gene engineering have contributed considerably to the diagnosis and treatment of hematopoietic malignancies, such as leukemia and malignant lymphoma. These advances also made possible precise determination of the clonal origin of malignant cells, the subtype of leukemia or lymphoma, and the clinical prognosis in each patient. Furthermore, minimal residual malignant cells in leukemia or lymphoma patients after achieving complete remission could be detected by DNA analysis. Based on these analyses, treatment can theoretically be tailored for each patient. We discuss in the present paper the usefulness of DNA or gene analyses of immunoglobulin heavy chain gene in clonal assessment of lymphocytic malignancies and in detecting minimal residual disease in the patient.

Aged↗
PubMed1998

Alterations in the colorectal carcinoma gene and protein in a novel human myeloid leukemia cell line with trisomy 18 established from overt leukemia after myelodysplastic syndrome.

A new human myeloid leukemia cell line (OIH-1), with alterations in chromosome 18 and the deleted in the colorectal carcinoma (DCC) gene and its product, was established from the peripheral blood (PB) of a patient with acute myeloblastic leukemia (AML) after myelodysplastic syndrome (MDS). Serial cytogenetics showed the presence of two clones, one with i(18)(q11) and another with trisomy 18. Southern blot analysis of OIH-1 cells with i(18)(q11) showed an extremely reduced intensity of 20- and 14-kb EcoRI fragments, suggesting the allelic loss of the DCC gene. Immunoprecipitation (IP) analysis by the murine monoclonal antibody (MoAb) AF5, specific for the DCC extracellular domain, failed to detect normal 180-kDa DCC protein, however extra 85-kDa protein was detected. However, Southern blot analysis of the latter clone of OIH-1 with trisomy 18 showed normal structure of the DCC gene. IP analysis with AF5 or G92-13 (specific for the extracellular domain) did not detect the DCC protein, but a 150-kDa protein other than the DCC-specific 180-kDa protein was detected with G97-449, specific for the cytoplasmic domain of the DCC protein. RT-PCR analysis showed the expression of the DCC mRNA in OIH-1 cells carrying each type of chromosome 18 abnormalities. These alterations in the DCC gene and protein may contribute to progression of malignancy for OIH-1 cells. The OIH-1 cell line may be useful for studying the role of the DCC gene in leukemogenesis of MDS or AML.

Aged↗
PubMed1998

Mature and immature myeloid cells decrease the granulocyte colony-stimulating factor level by absorption of granulocyte colony-stimulating factor.

We studied the effects of polymorphonuclear neutrophils (PMN) and immature myeloid cells on the granulocyte colony-stimulating factor (G-CSF) level in vitro to better understand the regulatory mechanisms of neutropoiesis. Intact normal PMN decreased the G-CSF level after incubation with recombinant human (rh) G-CSF in a time- and dose-dependent manner. The percent reduction decreased as the concentration of rhG-CSF increased. However, the cell-free PMN-conditioned medium (PMN-CM) did not decrease the G-CSF level. The intact PMN also decreased the granulocyte-macrophage (GM)-CSF level after culture with rhGM-CSF, but did not affect the monocyte (M)-CSF level after culture with rhM-CSF. Normal bone marrow (BM) immature neutrophilic cells and G-CSF-dependent acute myeloid leukemic cells (OCI/AML la) also decreased the G-CSF level, whereas K-562 cells, which have no detectable G-CSF receptors, did not affect it. Phenylarsine oxide (PhAsO), an inhibitor of endocytosis of ligand receptor complex, abrogated this decreasing effect of intact PMN and OCI/AML la cells. These findings suggest that mature and immature myeloid cells negatively regulate neutropoiesis by, at least in part, decreasing the G-CSF level probably through receptor-mediated continual absorption and metabolism of G-CSF.

Absorption↗
PubMed1998

A case of atypical chronic myeloid leukemia regarded as MDS with myeloproliferative features.

We report a case of atypical chronic myeloid leukemia (aCML) who showed marked neutrophilia without dysplastic features, basophilia or monocytosis. These findings diverged somewhat from the FAB criteria for aCML. The patient's erythroid cells and megakaryocytes were dysplastic. His marrow cells formed no spontaneous colonies, as shown by cell culture. The cells formed many small-sized neutrophil colonies with G-CSF stimulation. Interestingly, they formed mainly neutrophil colonies with GM-CSF stimulation. These findings were different from those of chronic myelomonocytic leukemia cells and chronic granulocytic leukemia cells. This aCML case showed the cytological features of myelodysplastic syndrome.

Humans↗
PubMed1998

[Proliferation and differentiation of leukemic cells in acute myelocytic leukemia].

Acute myelocytic leukemia is characterized as a malignant disease with excessive accumulation of leukemic cells and deterioration of hematopoiesis. We studied the mechanism by which leukemic cells proliferated in patients. The indefinite growth of leukemic cells is supported by leukemic blast progenitors with a self-renewal capacity. Hematopoietic growth factors, such as granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-3 (IL-3) or stem cell factor (SCF), have been revealed to stimulate the growth of leukemic blast progenitors. Furthermore, leukemic cells themselves produce and secrete hematopoietic factors that stimulate leukemic blast progenitors. The so-called autocrine growth mechanism has been postulated to play an important role in the pathophysiology of acute myelocytic leukemia. Leukemic cells show terminal differentiation under certain circumstances. For example, leukemic cells differentiate to neutrophils or macrophages in suspension culture. Leukemic cells of erythroleukemia (FAB M6) differentiate to granulocytic and erythrocytic lineages. The mechanisms involved in the proliferation and differentiation of leukemic cells in acute myelocytic leukemia are discussed in the article.

Cell Differentiation↗
PubMed1997

Molecular typing of methicillin-resistant Staphylococcus aureus by polymerase chain reaction: distribution of the typed strains in hospitals.

Three methods for molecular typing of methicillin-resistant Staphylococcus aureus using polymerase chain reaction (PCR) were compared. The method which amplified the variable number of tandem repeat of dru sequences grouped the isolates into six types. Whereas, the method examining restriction fragment length polymorphism of coagulase gene and the method using arbitrarily primed-PCR showed poor diversity in typing. We investigated the distribution of dru types in two hospitals. Obvious concentration of a type in one ward was not recognized in our hospital. In the other hospital, a rare type was detected from the inpatients in the pediatrics ward. It suggested that the infection was an epidemic. We also found that some patients were infected with more than two strains. Even if two isolates show the same type, it does not necessarily mean that they originated from one clone. However, this method brings meaningful information on nosocomial infection, more easily than other genotyping.

Bacterial Typing Techniques↗
PubMed1997

Effect of vesnarinone, a quinolinone derivative, on the growth of leukemic blasts in acute myelogenous leukemia.

We studied the effects of vesnarinone, a quinolinone derivative used clinically for the treatment of chronic congestive heart failure, on the leukemic blast progenitors in acute myelogenous leukemia (AML) patients and on the normal hematopoietic precursors, colony-forming unit in culture (CFU-C), and colony-forming unit erythroid (CFU-E). Leukemic blast progenitors made blast colonies in the presence of granulocyte-colony stimulating factor (G-CSF), granulocyte-macrophage CSF (GM-CSF), or interleukin-3 (IL-3). Blast colony-formation was suppressed by vesnarinone in a dose-responsive manner regardless of growth factor added. Vesnarinone suppressed the primary (PE1) and secondary (PE2) colony-formation of leukemic blast progenitors in six AML patients tested. The suppression by vesnarinone did not significantly differ between PE1 and PE2. This finding suggests that vesnarinone exerts an almost equivalent effects on the terminal divisions and the self-renewal of leukemic blast progenitors. Furthermore, this drug suppressed the growth of clonogenic cells of five AML cell lines, OCI/AML1a, OCI/AML2, OCI/AML3, OCI/AML5, and OCI/AML6. Normal hematopoietic precursors CFU-C and CFU-E were also suppressed by vesnarinone, although vesnarinone was less toxic to normal hematopoietic than to leukemic blast progenitors. The possible usefulness of vesnarinone as a new approach to the treatment of AML patients is discussed.

Adult↗
PubMed1997

[Responses to surgical stress in blood coagulation and fibrinolysis, platelet counts and thromboxane B2 after esophageal cancer operation].

Studies on responses to surgical stress in blood coagulation and fibrinolysis, platelet counts and thromboxane B2 (TXB2) were carried out with 18 esophageal cancer patients who had undergone radical esophagectomy through right thoracotomy and reconstruction with gastric tube. Plasma levels were measured for the following for coagulation assessment: thrombin.antithrombin III complex (TAT), soluble fibrin monomer complex(SFMC), fibrinogen, antithrombin III, protein C and thrombomodulin. Selected fibrinolytic markers are: tissue plasminogen activator.plasminogen activator inhibitor 1 complex (tPA.PAI1C), plasminogen, alpha 2 plasmin inhibitor, plasmin. alpha 2 plasmin inhibitor complex(PIC), FDP and D-dimer. Peripheral venous blood samples were taken from the patients before the operation, immediately after the operation and on each of the first, second, third, seventh and fourteenth day after the operation. It was observed that TAT, SFMC, tPA.PAI-1C and TXB2 were remarkably altered immediately after the operation. This indicates that the major surgical stress significantly activated coagulation, fibrinolysis and platelets. Higher plasma levels of TAT compared to the pre-operation level was recorded for two weeks after the operation. Furthermore, in four cases, SFMC became positive during three to seven days after operation. These facts indicate that the activation of coagulation persisted during the days after operation. PIC began to increase from the 2nd to 3rd days after operation, reaching the maximum on the 7th day. Biphasic changes which peaked twice on the 1st and 7th days after operation were shown in plasma levels of FDP and D-dimer. These results indicate that the activation of fibrinolysis also persisted during the days after operation. The activation of coagulation and fibrinolysis may persist at least for two weeks after major surgical operation. Careful observation for the states of these systems was thought to be needed during the post-operative days, and the molecular markers could be useful to assess subclinical changes of these systems.

Adult↗
PubMed1996

Clonal involvement of eosinophils in therapy-related myelodysplastic syndrome with eosinophilia, translocation t(1;7) and lung cancer.

We report a therapy-related MDS (RAEB) patient with eosinophilia, unbalanced translocation der(7)t(1;7) (q12;q22) and lung cancer. We observed no increase in cytokine levels in serum or in the conditioned medium (CM) of peripheral T cells cultured with or without IL-2. When bone marrow (BM) cells were cultured with GM-CSF, IL-3 and SCF in a semisolid system, the colonies were exclusively eosinophilic. Cytogenetic analysis of the colony cells identified the same chromosome abnormality in all metaphases to that of BM cells. Suspension and clonogenic colony assay of BM cells cultured with various cytokines showed predominant eosinophilic growth and differentiation with GM-CSF, but not with the other cytokines examined. These findings, together with mild morphological abnormalities of eosinophils, indicate clonal involvement of eosinophils in the myelodysplastic syndrome (MDS) clone, and that the eosinophilia was derived from the neoplastic clone with the translocation and was not associated with the patient's lung cancer.

Aged↗
PubMed1996

Differential expression of CD44 splice variants in malignant and benign pleural effusions.

Expression of CD44 isoform that contains variant exons (v1-v10) has been implicated in tumor progression and metastasis. Especially, CD44 isoform containing v6 (CD44v6) and that containing v7 (CD44v7) were shown to confer full metastatic behavior on tumor cells. We examined the expression of CD44v6 and CD44v7 in malignant pleural effusions (13 lung cancers and 4 non-lung cancers) and in benign pleural effusions (7 tuberculosis and 3 pneumonia) with Southern blot analysis of reverse transcription (RT)-polymerase chain reaction (PCR) products. CD44v6 was expressed not only in malignant pleural effusions (12 of 13 lung cancers and 4 of 4 non-lung cancers), but also in benign pleural effusions(9/10). In contrast, although expression of CD44v7 was found in most malignant pleural effusions (12 of 13 lung cancers and 4 of 4 non-lung cancers), it was found in only a few cases of benign pleural effusions. These results suggest that the expression of CD44v7 may be correlated with a tumor-specific event such as metastasis or dissemination in malignant pleural effusion, while no such correlation can be found with CD44v6.

Alternative Splicing↗