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Avalanche induced oscillation phenomena during reverse recovery of power PiN diodes are investigated for the purpose of “Design for EMI”. The oscillation phenomena are the major barrier to improve power diode performance since the oscillation can cause serious EMI, affecting power electronics system reliability. The mechanism of the oscillation is precisely modelled under various diode structures and current ranges. The result will contribute to the design methodology to attain stable yet high performance diodes and power electronics systems.

Allogeneic stem cell transplantation (allo-SCT) is used as curative therapy for malignant lymphoma, and reduced-intensity hematopoietic stem cell transplantation (RIST) is sometimes performed to avoid the toxicity and mortality associated with myeloablative allo-SCT. RIST is generally preferred for elderly patients with malignant lymphoma. A 62-year-old woman with follicular lymphoma (FL) involving bone marrow (BM) suffered relapse after autologous SCT. RIST was performed; cells were from an unrelated, fully human leukocyte antigen-matched donor. To study the hematopoietic reconstitution, BM biopsy specimens that were obtained at different times after RIST, were evaluated. Engraftment of donor cells was observed on days 19 and 48 after RIST, and residual FL in BM had completely disappeared by day 73 after RIST. This is the first report to document histological BM regeneration after RIST and disappearance of FL involving the BM.

Purpose The aim of the study was to analyze the methylation status of the promoter regions of p15 and p16 and to assess the prognostic significance of promoter hypermethylation in diffuse large B-cell lymphoma (DLBCL). Experimental design DLBCL was diagnosed by morphology and immunohistochemical analysis according to the World Health Organization (WHO) classification. The methylation status of CpG islands in the p15 and p16 promoters was analyzed by methylation-specific polymerase chain reaction in 49 DLBCLs. Results Hypermethylation of the p15 and p16 promoters was detected in 20 (41%) and 22 (45%) of the 49 DLBCLs, respectively. Among all patients with DLBCL, there was no significant difference in the overall survival between those with hypermethylated and unmethylated p15 (P = 0.442) or between those with hypermethylated and unmethylated p16 (P = 0.468). Therefore, methylation was analyzed in combination with evaluation of clinical features using the international prognostic index (IPI). In the high-intermediate-risk and high-risk groups, patients with hypermethylated p16 had significantly lower survival rates than those of patients in the same risk group with unmethylated p16 (P = 0.010). Conclusions Our results suggest that hypermethylation of the p16 promoter indicates a poor prognosis in high-intermediate-risk and high-risk DLBCL patients, and may be a useful marker for selection of appropriate treatment when used in conjunction with the IPI.

Summary. Cyclin A (A2) and cyclin A1 are members of the G2 cyclins, which are involved in the control of G2/M and G1/S transitions as well as mitosis. Human cyclin A1 was cloned as an A-type cyclin that is highly expressed in acute myeloid leukaemia (AML). The clinical significance of these cyclins in myeloid leukaemia remains to be clarified. We investigated the relative levels of these transcripts in 80 patients with de novo AML. Correlations with clinical parameters showed that the initial white blood cell count and serum lactate dehydrogenase levels were inversely associated with cyclin A (A2) mRNA levels (r = −0·276, P = 0·019) and cyclin A1 mRNA levels (r = −0·241, P = 0·042) respectively. They were independently associated with increased overall survival [P = 0·035 for cyclin A (A2) and P = 0·016 for cyclin A1]. Multivariate analysis using Cox's proportional hazard model showed that elevated cyclin A1 mRNA levels contributed significantly to the better prognosis of patients with AML. Furthermore, the analysis of survival probability showed that the group with high levels of both cyclin A (A2) and A1 survived significantly longer than the group with low expression of both these cyclins (P = 0·002). These data indicate that high expression levels of both cyclin A (A2) and A1 are associated with good prognosis in AML patients.

Electromagnetic interference (EMI) noise byavalanche oscillations is the major barrier to improve powerdevice performance. Especially the oscillations of three-terminaldevices are more complex than two-terminal devices in point ofthe mutual relationship between devices and external circuit. Scattering parameter (S-parameter) under avalanche condition is obtained to establish stable-unstable criterion with stability factor (K-factor). The stable-unstable criterion clearly indicates the unstable frequency range with each change in MOSFET design. In addition the oscillation mechanism on power MOSFET is modeled with junction capacitance, which is the same as that of diode. For EMI suppression, resonant frequency of external circuit has to be different from unstable frequency of MOSFETs., 2012 24th International Symposium on Power Semiconductor Devices and ICs (ISPSD 2012), June 3-7, 2012, Bruges, Belgium

A 21-year-old man was admitted to our hospital for acute hepatitis of unknown cause. His liver function improved with rest, but worsened 2 months later. He developed a high fever and pancytopenia. The serum level of cytokines including TNF-alpha, IFN-gamma, IL-6, and M-CSF was elevated, and hemophagocytes were seen in bone marrow. These findings suggested a hemophagocytic syndrome-like state. With prednisolone, gamma-globulin, and G-CSF, the high fever disappeared and the patient's liver function gradually recovered. However, the severe pancytopenia persisted. The bone marrow became acellular with a small number of hemophagocytes, and hepatitis-associated aplastic anemia was diagnosed. After immunosuppressive therapy with ATG, CyA and G-CSF was started, and the patient showed hematopoietic reconstitution. The bone marrow CD4+/CD8+ lymphocyte ratio recovered to within the normal range, and the serum cytokines including TNF-alpha and IFN-gamma decreased. The increase in serum cytokines, particularly TNF-alpha and INF-gamma, as well as the presence of activated T cells associated with the preceding hemophagocytic syndrome-like state may have predisposed this patient to aplastic anemia.

A 22-year-old female was diagnosed as having acute lymphoid leukemia (ALL) in February 1995, from the findings of peroxidase negative, CD10+, CD19+, TdT+ and rearrangement of IgH and TCR beta. AdVP (doxorubicin, vincristine and prednisolone) therapy achieved a complete remission (CR). Bone marrow transplantation had to be abandoned because of the lack of an HLA-identical donor. Intensification therapy was thus carried out repeatedly. In June 1998, myeloblast with Auer rods, peroxidase positive, CD13+, CD33+ and HLA-DR+, appeared. The patient was diagnosed as having lineage switch acute myeloid leukemia (AML) from ALL. Though A-DMP (cytosine arabinoside, daunorubicin, 6-mercaptopurine) therapy was resistant, AdVP therapy led to a CR. The patient died of cardiotoxicity from anthracyclines in February 1999. From the results of the Ramasamy method using the clonal rearrangements of the Ig heavy chain gene locus, the origin of the pathological cells of ALL and AML was indicated to be the same leukemia clone.

Some follicular lymphomas histologically transform into diffuse aggressive lymphomas, the prognosis of which is poor. There are, however, no reliable histological criteria for predicting which cases will later undergo such transformation. In low-grade B-cell lymphomas, follicular dendritic cells form dense mesh-like networks that contain accumulating neoplastic B-cells. These are rare in high-grade lymphomas. We immunohistochemically analyzed CD21-positive follicular dendritic cells in 32 follicular lymphomas, including 3 transformed lymphomas, in addition to immunohistological study using P-glycoprotein, p53, and Ki-67. We found that the mesh-like networks in follicles are more clearly defined in low-grade lymphomas than in high-grade lymphomas (p = 0.015). Neoplastic follicles in 2 transformed lymphomas lost the networks of follicular dendritic cells before transformation despite the existence of morphologically clear follicles. This differed from the non-transformed cases of the same cytological grades. Prognosis was statistically better for patients with low-grade tumor than for those with high-grade tumor (p = 0.026), and there was a trend toward poorer survival among CD21-negative cases (p = 0.186). P-glycoprotein, p53, and Ki-67 expressions did not provide sufficient information to predict the transformation of follicular lymphoma. The presence of CD21-positive follicular dendritic cells in neoplastic follicles might help predict the potential of follicular lymphoma to transform to diffuse large B-cell lymphoma.

A 16-year-old girl was admitted to our hospital because of high fever, abdominal pain, and jaundice. Abnormal lymphocytes and hemophagocytic cells had infiltrated the bone marrow. Laboratory data revealed a severe type of hemophagocytic syndrome accompanied by an initial Epstein-Barr virus (EBV) infection. Persistent EBV infection was identified by polymerase chain reaction (PCR) detection of EBV-DNA in peripheral blood and bone marrow mononuclear cells. The limited efficacy of initial treatment with high-dose gamma-globulin, plasmapheresis, and high-dose methylprednisolone prompted us to administration of T-COP-E (VP-16). Two courses of T-COP-E improved the patient's clinical symptoms and laboratory data; however, marked splenomegaly remained. In addition, fever and serum increase of lactate dehydrogenase (LDH) and cytokines such as gamma-interferon recurred shortly after chemotherapy. On day 53 after diagnosis, the patient underwent laparoscopic splenectomy. The resected spleen weighted 420 g and abnormal lymphocytes in the spleen were positive for CD 8 and negative for CD 56. In situ hybridization revealed EBV-encoded small RNAs (EBERs) in the abnormal lymphocytes. Clinical symptoms including high fever disappeared shortly after the splenectomy, and laboratory data returned to normal. Lymphocytosis after the splenectomy was not observed. We continued out patient monitoring of the case, and 16 months after diagnosis, EBV-DNA in peripheral blood mononuclear cells was not detected, even by PCR.

The various spare ability of the internal organs declines in the elderly ITP. There are not a few who have some complications such as diabetes mellitus and cardiovascular disease. So, various restrictions are often taken in the treatment. PSL is the effective drug most securely against ITP. However, it is necessary in elderly ITP to reduce the amount of PSL, because the various side effects including the decline of QOL. On the other hand, the elimination therapy against Helicobacter pylori is carried out for only one week and remission lasts for a long time, and side effect is little. This elimination therapy is useful treatment for elderly ITP. It is important to improve and elevate QOL of the patient.

A 73-year-old man noticed a subcutaneous tumor on the left upper palpebra from April 1998, but did not seek therapy for it. Facial subcutaneous tumors appeared from November 1999, and multiple tumors appeared on the skin of the chest and both upper arms from January 2000. Tumor biopsy revealed that these tumors were non-Hodgkin lymphoma showing CD19 (+), CD20 (+), CD5 (+), CD10 (-), smIgM (+), sm lambda (+) and cyclin D1 (+). The karyotype was t(11;14) (q13;q32), but bcl-1 gene rearrangement was not detected. On the basis of these data, primary mantle cell lymphoma (MCL) of the subcutis was diagnosed. The patient underwent eight courses of THP-COP therapy, and complete remission was achieved. Primary subcutaneous B-cell lymphoma, especially MCL, is rare. MCL is aggressive and difficult to cure; the median survival of patients is 3 to 5 years, and the 5-year survival is 30%. However, the present patient showed a good response to chemotherapy, and complete remission has continued for 17 months since the MCL was first diagnosed.