44 research outputs found

    Using NASA Standard Breakup Model to Describe Low-Velocity Impacts on Spacecraft

    Get PDF
    The applicability is examined of the hypervelocity collision model included in the NASA standard breakup model 2000 revision to low-velocity collisions possible in space, especially in the geosynchronous regime. The analytic method used in the standard breakup model is applied to experimental data from low-velocity impact experiments previously performed at Kyushu University at a velocity range less than 300 m/s. The projectiles and target specimens used were stainless steel balls and aluminum honeycomb sandwich panels with face sheets of carbon fiber reinforced plastic, respectively. It is concluded that the hypervelocity collision model in the standard breakup model can be applied to low-velocity collisions with some simple modifications

    Feasibility of cord blood transplantation in chemosensitive adult T-cell leukemia/lymphoma: a retrospective analysis of the Nagasaki Transplantation Network

    Get PDF
    It has been reported that cord blood transplantation (CBT) for patients with aggressive adult T-cell leukemia/ lymphoma (ATL) results in poorer outcomes than transplantation using other stem cell sources. To identify a subset of ATL in which CBT is feasible, we retrospectively analyzed 27 patients treated with CBT at three institutions in Nagasaki Prefecture, Japan. The estimated overall survival (OS) rate at 3 years was 27.4 %. Of 16 patients who received CBT during remission (complete, CR, or partial, PR), the OS rate at 3 years was 50 %, while during refractory periods (non-CR or non-PR), the OS rate was 9.1 %. Reduced intensity conditioning (RIC) was given to 18 patients, and myeloablative conditioning (MAC) was used in nine, with 3-year OS of 50.0 and 0 %, respectively. Of the 19 deaths, nine were due to progressive disease, eight (five MAC and three RIC) to infection, and two to multiple organ failure. These results suggest that CBT provides similar results with those in other transplantation procedures for selected ATL patients, such as those in CR or PR. Further studies are needed to evaluate the use of CBT in aggressive ATL

    Successful outcome of second allogeneic bone marrow transplantation for blastic plasmacytoid dendritic cell neoplasm with MYC locus rearrangement

    Get PDF
    A 62-year-old male was diagnosed with blastic plasmacytoid dendritic cell neoplasm (BPDCN) with a MYC rearrangement. Four months after the first unrelated bone marrow transplantation (BMT), he developed the relapsed BPDCN. After the achievement of partial remission following re-induction therapy, he underwent a second BMT from another unrelated donor, and experienced complete remission with grade II acute graft-versus-host disease and moderate chronic graft-versus-host disease. He remains alive in complete remission more than 71 months after the second BMT. These results suggested that donor change at the second transplantation may represent a considerable therapeutic option for patients with relapsed BPDCN

    Successful treatment of a chronic-phase T-315I-mutated chronic myelogenous leukemia patient with a combination of imatinib and interferon-alfa

    Get PDF
    The T315I BCR-ABL mutation in chronic myelogenous leukemia (CML) patients is responsible for up to 20% of all clinically observed resistance. This mutation confers resistance not only to imatinib, but also to second-generation BCR-ABL tyrosine kinases, such as nilotinib and dasatinib. A number of strategies have been implemented to overcome this resistance, but allogeneic stem cell transplantation remains the only established therapeutic option for a cure. A 61-year-old male was diagnosed with Philadelphia chromosome-positive chronic-phase CML in 2002. He was initially treated with imatinib and complete cytogenetic response (CCyR) was achieved 12 months later. However, after 18 months, a loss of CCyR was observed and a molecular study at 24 months revealed a T315I mutation of the BCR-ABL gene. At 30 months, imatinib/interferon-alfa (IFNα) combination therapy was initiated in an effort to overcome the resistance. Thirty months later, he re-achieved CCyR, and the T315I BCR-ABL mutation disappeared at 51 months. To our knowledge, this is the first case report showing the effectiveness of imatinib/IFNα combination therapy for CML patients bearing the T315I BCR-ABL mutation

    Expression of myeloperoxidase and gene mutations in AML patients with normal karyotype: double CEBPA mutations are associated with high percentage of MPO positivity in leukemic blasts.

    Get PDF
    The percentage of myeloperoxidase (MPO)-positive blast cells is a simple and highly significant prognostic factor in AML patients. It has been reported that the high MPO group (MPO-H), in which >50% of blasts are MPO activity positive, is associated with favorable karyotypes, while the low MPO group (≤50% of blasts are MPO activity positive, MPO-L) is associated with adverse karyotypes. The MPO-H group shows better survival even when restricted to patients belonging to the intermediate chromosomal risk group or those with a normal karyotype. It has recently been shown that genotypes defined by the mutational status of NPM1, FLT3, and CEBPA are associated with treatment outcome in patients with cytogenetically normal AML. In this study, we aimed to evaluate the relationship between MPO positivity and gene mutations found in normal karyotypes. Sixty AML patients with normal karyotypes were included in this study. Blast cell MPO positivity was assessed in bone marrow smears stained for MPO. Associated genetic lesions (the NPM1, FLT3-ITD, and CEBPA mutations) were studied using nucleotide sequencing. Thirty-two patients were in the MPO-L group, and 28 patients in the MPO-H group. FLT3-ITD was found in 11 patients (18.3%), NPM1 mutations were found in 19 patients (31.7%), and CEBPA mutations were found in 11 patients (18.3%). In patients with CEBPA mutations, the carrying two simultaneous mutations (CEBPA (double-mut)) was associated with high MPO expression, while the mutant NPM1 without FLT3-ITD genotype was not associated with MPO activity. Both higher MPO expression and the CEBPA (double-mut) genotype appeared to be associated with improved overall survival after intensive chemotherapy. Further studies are required to determine the importance of blast MPO activity as a prognostic factor, especially in CEBPA wild-type patients with a normal karyotype

    Molecular analysis of the BCR-ABL1 kinase domain in chronic-phase chronic myelogenous leukemia treated with tyrosine kinase inhibitors in practice: Study by the Nagasaki CML Study Group

    Get PDF
    An appropriate trigger for BCR-ABL1 mutation analysis has not yet been established in unselected cohorts of chronic-phase chronic myelogenous leukemia patients. We examined 92 patients after 12 months of tyrosine kinase inhibitor (TKI) treatment in Nagasaki Prefecture, Japan. Univariate analysis revealed that significant factors associated with not attaining a major molecular response (MMR) were the presence of the minor BCR-ABL1 fusion gene, a low daily dose of TKI, and the emergence of BCR-ABL1 kinase domain mutations conferring resistance to imatinib. Factors associated with the loss of sustained MMR were a low daily dose of TKI and the emergence of alternatively spliced BCR-ABL1 mRNA with a 35-nucleotide insertion. Taken together, our results suggest that the search for BCR-ABL1 mutations should be initiated if patients have not achieved MMR following 12 months of TKI treatment
    corecore