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Biomedical subjects

K Miyamura

Publications and source records attributed to K Miyamura.

At least 19 recordsLinked to original sources
PubMed2006

Short-term methotrexate could reduce early immune reactions and improve outcomes in umbilical cord blood transplantation for adults.

Post transplant immune disorders are problematic in cord blood transplantation (CBT) for adult patients, and optimal prophylaxis has not been established. We investigated whether intensive graft-versus-host disease (GVHD) prophylaxis using short-term methotrexate (MTX) has a prognostic impact on CBT. Post-CBT immune reactions were classified according to time course as pre-engraftment immune reaction (PIR), engraftment syndrome (ES) or acute GVHD. Between March 2001 and November 2005, a total of 77 patients underwent CBT at eight transplantation centers. Median age was 48 years (range, 18-69 years). Preparative regimens comprised myeloablative (n=31) or reduced-intensity (n=46). Acute GVHD prophylaxis included cyclosporine alone (n=23), tacrolimus alone (n=12), cyclosporine plus MTX (n=17), tacrolimus plus short-term MTX (n=23) or cyclosporine plus methylprednisolone (n=2). Cumulative incidences of PIR, ES and grade II-IV GVHD were 36, 12 and 23%, respectively. Short-term MTX exerted significant favorable effects on post-CBT immune reactions (hazard ratio, 0.55; 95% confidence interval (95% CI), 0.31-0.98; P=0.04) in multivariate analysis. Overall survival rates for patients with and without short-term MTX at day 180 were 59% (95% CI, 42-73%) and 16% (95% CI, 6.6-30%) (P=0.0001), respectively. Short-term MTX could offer one optimal regimen to reduce immune reactions and improve outcomes in CBT.

Adolescent↗
PubMed2006

Significance of additional high-dose cytarabine in combination with cyclophosphamide plus total body irradiation regimen for allogeneic stem cell transplantation.

The combination of cyclophosphamide (CY) and total body irradiation (TBI) has been used as a standard conditioning regimen for allogeneic transplantation. Several studies showed an advantage of adding high-dose cytarabine (HDCA) to this regimen. To clarify the significance of additional HDCA, we conducted a retrospective multicenter study and compared the clinical results of these two regimens. From June 1985 to March 2003, 219 patients with hematological malignancies underwent allogeneic transplantation after conditioning with CY+TBI 12Gy (n=73) or CA+CY+TBI 12Gy (n=146). Engraftment, overall survival, transplant-related mortality (TRM), relapse rate and incidence of graft-versus-host disease (GVHD) were compared according to risks and donors. Addition of HDCA had no impact on the relapse rate in all subgroups, and it was associated with lower TRM among standard-risk patients after related transplantation, and with higher TRM and worse survival among standard-risk patients after unrelated transplantation. The incidence of acute GVHD was not significantly different between the two regimens, and HDCA resulted in a higher incidence of chronic GVHD among standard-risk patients after related transplantation. In summary, addition of HDCA is not beneficial for high-risk patients, and is not recommended for standard-risk patients receiving unrelated transplantation.

Adolescent↗
PubMed2005

Increased frequency of the angiotensin-converting enzyme gene D-allele is associated with noninfectious pulmonary dysfunction following allogeneic stem cell transplant.

Noninfectious pulmonary dysfunction (NIPD) is a common and often fatal complication associated with allogeneic hematopoietic stem cell transplantation (HSCT). An insertion/deletion polymorphism in the angiotensin-converting enzyme (ACE) gene has been extensively studied in relation to cardiovascular and renal disease, and lung fibrosis. In pulmonary fibrosis, D-allele frequency is significantly higher than in the control population. We hypothesized that a similar mechanism exists between post-HSCT NIPD and pulmonary fibrosis in the absence of HSCT. We retrospectively analyzed the incidence of NIPD and the ACE genotype polymorphism in 118 Japanese patients who underwent HSCT from HLA-identical sibling donors. NIPD occurred in 17 cases. Deletion/deletion genotype carriers were more common in the NIPD group than in the other 101 patients (41.2 vs 11.9%; hazard ratio, 5.19; 95% confidence interval, 1.67-16.21). There were no significant relationships between the clinical characteristics of patients and the development of NIPD. These findings suggest that the ACE genotype is associated with the development of NIPD following HSCT. This study is the first to report the relationship between genetic background and NIPD.

Adolescent↗
PubMed2003

Attitudes to HIV voluntary counselling and testing among mineworkers in South Africa: will availability of antiretroviral therapy encourage testing?

We conducted a study to identify attitudes that influence uptake of HIV voluntary counselling and testing (VCT) amongst gold mine workers in South Africa; 105 healthy men were interviewed. The level of basic knowledge of HIV was high, but reported awareness of the extent of HIV infection in the workforce and perceived personal risk of HIV infection was low. Health issues were considered the most important indication for HIV testing and one-third had been tested. Fear of testing positive for HIV and the potential consequences, particularly stigmatization, disease and death, were the major identified barriers to VCT. Half of the participants felt workplace education programmes needed to be improved to promote VCT access. Twenty-six per cent became more favourably inclined towards HIV testing in response to information on improvements that have been made to the confidentiality and convenience of the company's VCT service. Only 14% then indicated that they would be more likely to access VCT if antiretroviral therapy became available. A vigorous community education programme is essential if the introduction of ART is to be effective in promoting uptake of VCT.

Adult↗
PubMed2001

Acute promyelocytic leukemia with apparently normal karyotype: molecular findings and response to all-trans retinoic acid.

Acute promyelocytic leukemia (APL) is specifically associated with a reciprocal translocation, t(15; 17)(q22; q21), leading to the formation of a fusion of the retinoic acid receptor-alpha (RARA) gene and the promyelocytic leukemia (PML) gene. However, there are several reports describing APL cases lacking the t(15; 17). Many such cases are those bearing variant translocations involving chromosomes 15 or 17, and those with no chromosomal aberrations have rarely been reported. We have studied a patient with APL showing an apparently normal karyotype which was confirmed by spectral karyotyping (SKY). A submicroscopic PML-RARA fusion was identified by reverse transcriptase-polymerase chain reaction (RT-PCR) and fluorescent in situ hybridization (FISH). All-trans retinoic acid (ATRA) was effective as the initial therapy for remission induction and as the reinduction therapy after a relapse. The present study shows the key role of the fusion of PML-RARA in the responsiveness to ATRA as well as in the leukemogenesis of APL.

Antineoplastic Agents↗
PubMed2001

Transatrial repair of ventricular septal rupture under preoperative localization by transesophageal echocardiography.

We report about a 71-year-old woman with postinfarction ventricular septal rupture who was successfully treated by the transatrial closure under preoperative localization by transesophageal echocardiography. In an attempt at transatrial repair of the ventricular septal rupture, the most important thing is preoperative localization of the defect in the septum, which is located high and posterior, where it is smooth with relatively few trabeculations and can be readily exposed by retraction of the tricuspid valve.

Aged↗
PubMed2000

Benign schwannoma of the esophagus removed by enucleation: report of a case.

A submucosal tumor of the esophagus was enucleated by a thoracotomy. A microscopic examination showed the tumor to be composed of spindle-shaped cells showing mild nuclear atypia with vague nuclear palisading and scarce mitotic figures. The tumor was surrounded by peripheral lymphoid cuffs. An immunohistochemical study demonstrated diffuse positive staining for S-100 protein in the tumor cells. The lesion was diagnosed to be an esophageal schwannoma based on these pathological features. Benign schwannoma of the esophagus has been described in five cases in four reports in the English literature. This is the sixth case diagnosed by immunohistochemical studies.

Esophageal Neoplasms↗
PubMed2000

Gelatin beads as platforms for targeting molecule and anti-Fas antibody: two major properties of cytotoxic T lymphocytes.

OBJECTIVE: Cytotoxic T lymphocytes (CTL) initially recognize target cells using the T-cell receptor (TCR), then strongly adhere to these cells by accessory molecules, and finally induce apoptosis by Fas ligand (FasL)/Fas or lyse by the granzyme/perforin system. We describe the development of gelatin beads carrying anti-tumor monoclonal antibody (mAb) and anti-Fas mAb mimicking the TCR and FasL, respectively. We hypothesized that these antibody-coated beads can be therapeutically utilized for the elimination of tumor cells. MATERIALS AND METHODS: We evaluated the cytotoxic activity of gelatin beads bearing CH11 (anti-Fas mAb) after incubation with several human leukemia cell lines. Cytotoxic activities were measured using colorimetric DNA fragmentation assay and lactate dehydrogenase (LDH) release assay. RESULTS: We demonstrated that the cytotoxic effects of anti-Fas mAb were markedly enhanced by fixation on gelatin beads. Microscopic examination showed that the beads attached to the target cells and induced their apoptosis. These effects were enhanced further by adding tumor-specific mAb. These in vitro properties of the beads were well reconstituted in the peritoneal cavity of mice. CONCLUSION: Although antibody-coated gelatin beads lack several important properties of natural CTL, such as differentiation, proliferation, and the functions of adhesion molecules, they mimic well the targeting and cytotoxic functions of natural CTL. Our findings suggest that antibody-carrying gelatin beads may be the first step toward the development of artificial CTL and can be applied, for example, to artificial dendritic and stroma cells for the development of novel biotherapeutic approaches.

Animals↗
PubMed2000

Successful ribavirin therapy for severe adenovirus hemorrhagic cystitis after allogeneic marrow transplant from close HLA donors rather than distant donors.

Intravenous ribavirin was given to nine patients who had developed severe adenovirus-induced hemorrhagic cystitis (AD-HC) which was resistant to conventional therapy or where there was involvement of other organs after allogeneic BMT. Three patients recovered completely from AD-HC, two of whom had been resistant to vidarabine. All three had received sibling BMTs (2 HLA matched, 1 HLA mismatched). Five patients who received BMTs from related (2 HLA mismatched) or unrelated (1 HLA matched, 2 HLA mismatched) showed an improvement in symptoms but had recurrent AD-HC after discontinuation of ribavirin. Improvement in clinical symptoms and termination of virus excretion were well correlated. The last patient who received a mismatched unrelated BMT died during ribavirin therapy. Ribavirin was notably more effective among patients receiving BMTs from siblings in contrast to patients receiving BMTs from alternative donors (<0.05). One patient experienced severe pancytopenia during the second treatment with ribavirin after HC recurrence and recovered after ceasing ribavirin. Thus, ribavirin seems to be very effective for severe AD-HC for some recipients who receive transplants from a genetically close donor. Bone Marrow Transplantation (2000) 25, 545-548.

Adenoviridae Infections↗
PubMed1999

Accurate quantitation of residual tumor burden at bone marrow harvest predicts timing of subsequent relapse in patients with common ALL treated by autologous bone marrow transplantation. Nagoya BMT Group.

We have investigated whether the extent of residual leukemia at bone marrow harvest can predict subsequent relapse after autologous bone marrow transplantation (BMT). A total of 29 pre- and post-purged marrow samples from 15 patients with high-risk common acute lymphoblastic leukemia were examined. An accurate quantitation of residual disease was achieved by phage library assay using polymerase chain reaction to amplify the third complementarity determining region of the immunoglobulin gene. The estimated rate of disease-free survival at 3 years was significantly higher for the patients with less than 5% residual disease among total B cells than for those with greater than 5% before purging (87.5% vs 0%, P = 0. 0013). Furthermore, among patients with subsequent relapse, there was a linear correlation between the quantitated residual tumor burden of pre-purged marrow and remission duration after BMT (r2 = 0. 888). An accurate quantitative assessment of residual disease in the autograft has a high predictive value for subsequent relapse. A serial assay of residual disease would help us to individualize the treatment for each patient after induction or consolidation therapy.

Adult↗
PubMed1998

Recombinant adeno-associated virus-mediated gene transfer into human leukemia cell lines.

Adeno-associated virus (AAV)-based vector is a promising gene transfer vehicle by virtue of the characteristics of wild-type AAV:tropism to a wide range of human tissues and locus-specific integration at chromosome 19q13.3. To elucidate the nature of the recombinant AAV (rAAV), transduction of neomycin phosphotransferase enzyme gene (NeoR gene) into seven human leukemia cell lines was performed. Transduction efficiencies were assessed by colony formation assay and limiting dilution assay. The results suggested that both assays are comparable. Transduction efficiencies of the NeoR gene into K-562, MEG-O1, Raji, MOLT-3, HL-60, U937 and NKM-1 at a multiplicity of infection (MOI) of 0.1 were 0.27, 0.25, 0.015, 0.009, < 0.0025 and < 0.0025%, respectively. After purification and concentration of rAAV, 27% efficiency was observed in K562 at an MOI of 7 and a linear relationship between MOI and efficiency was confirmed, suggesting that this system may be useful for gene transduction into leukemia cells. Integration of the NeoR gene into the host genome was detected by Southern blotting analysis, which showed various sizes of digested fragments. A fluorescent in situ hybridization (FISH) study was carried out on 11 clones, in all of which the NeoR gene was integrated out of chromosome 19q13.3. In five of the clones, whole chromosome painting probes revealed that the integration sites were chromosomes 1q, 2q, 2q, 11p, 12p and 13q.

Dependovirus↗
PubMed1997

Functional expression of Fas (CD95) in acute myeloid leukemia cells in the context of CD34 and CD38 expression: possible correlation with sensitivity to chemotherapy.

Clinical studies of bone marrow transplantation (BMT) suggest that the immune system contributes to the eradication of acute myeloid leukemia (AML). A recent study also showed that the Fas (CD95/APO1) mediates apoptotic signal from cytotoxic T lymphocytes. Sixty-four patients with AML were studied for the expression of Fas in the context of CD34 and CD38 coexpression. The clinical relevance of Fas expression and function on AML was also investigated. Fas was expressed on 2% to 98% of AML cells (2% to 20% in 11 patients, 20% to 50% in 20 patients, 50% to 80% in 24 patients, and 80% to 98% in nine patients). Only 44.4% of patients with AML M1 (French-American-British [FAB] classification) were Fas+ (>/=20% of leukemia cells expressed Fas), whereas 89.1% of patients with AML M2, M3, M4, M5 were Fas+ (P < .01). Among 43 CD34+ patients (>/=20% leukemia cells were CD34+), 34 were Fas+, and 19 of 21 CD34- patients were Fas+ (P = NS). Thirteen cases were studied for their expression of Fas in the context of CD34 and CD38 using three-color analysis. Fas is expressed at a high level in the gated CD34+CD38+/- and CD34+CD38+ population. In 10 AML samples, Fas was expressed at a higher level in CD34+/CD38+ population than in CD34+/CD38+/- or CD34- cell populations. Fas-induced apoptosis by anti-Fas monoclonal antibody (MoAb) was determined by morphologic features and colorimetric DNA fragmentation assay. Induction of apoptosis was found in 14 of 24 cases. However, no statistically significant correlation was observed between Fas expression and induction of apoptosis. Leukemia colony-forming unit assays suggested that in some cases, Fas-induced apoptosis occurred in the clonogenic cell populations. Parameters such as laboratory and clinical data at initial diagnosis were correlated with Fas expression and only response to initial induction chemotherapy showed significant correlation with Fas expression (P < .05). We conclude that the majority of AML cells exhibit variable expression of Fas, and apoptosis could be induced by anti-Fas MoAb in some cases. Our results suggest the Fas-mediated apoptosis may be clinically relevant, whereas the issue of clonogenic leukemia cells and Fas expression needs further studies.

ADP-ribosyl Cyclase↗
PubMed1997

Correlation between Oscillation Modes and Penetration Rate of Protons in the Three-Phase-Liquid-Membrane Oscillation System

In the three-phase liquid-membrane system consisting of water-nitrobenzene-water, the decrease in pH of aqueous phases is found to be accompanied with the spontaneous electric oscillation of several modes. The increase rates of proton concentration in each aqueous phase are found to differ considerably in each modes of electric oscillation. Furthermore, the presence of an aqueous phase without surfactant is found to accelerate the proton penetration rate through nitrobenzene-water interface. The mechanisms for each mode of oscillation are discussed.

Journal Article↗
PubMed1997

Comparison of gelatin particle agglutination and hemagglutination inhibition tests for measles seroepidemiology studies.

The prevalence of measles antibody in Japan was surveyed with a newly developed gelatin particle agglutination (PA) test, and the results compared with those of the hemagglutination inhibition (HI) test. The two age-distribution curves of the PA antibody-positive rates at > or = 1:8 and > or = 1:32 were almost the same in all the age groups, except the less-than-1-year-old group for which the rate at > or = 1:8 was higher than that at > or = 1:32 (p < 0.05, chi 2 test). In the vaccinated children, all groups older-than-1-year of age had antibody-positive levels of 96% or more. In contrast, in the unvaccinated children, there was a sharp increase in antibody-positive rates between the 1- and 4-year-old groups, indicative that about 80% of the children were infected by wild measles virus at these ages. A significant number of PA antibody-positive specimens were antibody-negative (< 1:8) by HI. The percentage of specimens in this category, PA (+) but HI (-), was greatest in infants less than one year old, and least in young children, but it increased with age to 97% of the HI (-) specimens from adults of more than 20 years of age. The PA test therefore detected some measles antibodies that HI could not. This test is simple and useful for making serosurveys in both developed and developing countries.

Adolescent↗
PubMed1997

Development of a gelatin particle agglutination reagent for measles antibody assay.

A new agglutination test that utilizes gelatin particles as the carrier of measles antigen was developed and used to evaluate immune status to measles virus infection. The particle agglutination (PA) reagent reacted with monoclonal antibodies against two major proteins of measles virus, the hemagglutinin (H) and fusion (F) proteins. Children were followed individually for ten years for measles antibody. Results showed that the PA test was as sensitive and specific as the plaque neutralization test. The procedure is simple and rapid. No prior treatment of specimens is needed, and the test is completed in a single reaction. The PA test therefore can be used for diagnoses and epidemiologic surveys of measles virus infection.

Agglutination Tests↗