[Five adult cases of Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis].

Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis (EBV-HLH) is more common in children, and is characterized by pancytopenia, liver dysfunction and coagulopathy caused by interactions between EBV-infected T cells and activated macrophages. We describe here five adults with EBV-HLH. The median age was 17 years (range 16 approximately 40).

Primary mediastinal non-seminomatous germ cell tumor associated with hemophagocytic syndrome.

A 20-year-old man with a primary non-seminomatous mediastinal germ cell tumor (yolk sac tumor and immature teratoma) developed hemophagocytic syndrome (HPS) three months after surgical resection. Around the same time, the patient was found to have bone metastases of the germ cell tumor. No other hereditary or acquired diseases related to HPS were found.

Adult patient with Epstein-Barr virus (EBV)-associated lymphoproliferative disorder: chronic active EBV infection or de novo extranodal natural killer (NK)/T-cell lymphoma, nasal type?

Chronic active Epstein-Barr virus (EBV) infection, which is considered to be a childhood disease, often develops into natural killer (NK) or T-cell lymphoma after recurrent infectious mononucleosis (IM)-like symptoms. We describe a 56-year-old woman who developed NK-cell lymphoma after 9 months of recurrent IM-like symptoms. The patient had an unusual anti-EBV antibody profile.

[Expression analysis of microRNAs in erythropoiesis].

microRNAs (miRNAs) are non-coding RNAs, and are negatively regulating the gene functions through translational repression or digesting mRNAs by targeting 3'-UTR in messenger RNAs (mRNAs). To clarify roles of miRNAs in normal and pathological erythropoiesis, we analyzed the expression of miR-451, miR-155, miR-221 in normal human erythroid colony forming cells (ECFCs) and circulating red blood cells using quantitative real-time polymerase chain reaction. Remarkable down-regulation of miR-155 (about 200-fold) and up-regulation of miR-451 (270-fold) were observed during 12 days of ECFC cultures.

[Two young adult cases of Epstein-Barr virus associated-hemophagocytic lymphohistiocytosis with monoclonal proliferation of virus-infected cells within a short period after primary infection].

Hemophagocytic lymphohistiocytosis (HLH) is a rare but severe complication of Epstein-Barr virus (EBV) infection. Interactions between EBV-infected T cells and activated macrophages cause several conditions such as pancytopenia, liver dysfunction and coagulopathy. We describe here two young adults with EBV-associated HLH with monoclonal proliferation of EBV-infected T cells within a short period after infectious mononucleosis as a primary infection.

[Graves' disease with splenomegaly and pancytopenia, mimicking B-cell lymphoproliferative disease].

A 48-year-old woman was referred to our hospital because of fever and general fatigue. Peripheral blood analysis showed a hemoglobin level of 82 g/l, a white blood cell count of 1.95 x 10(9)/l and a platelet count of 80 x 10(9)/l.

[Successful cyclosporine treatment for thrombocytopenia after salvage therapy with arsenic trioxide therapy followed by autologous hematopoietic stem cell transplantation in acute promyelocytic leukemia].

A 55-year-old man with acute promyelocytic leukemia in the first relapse was treated with arsenic trioxide as salvage therapy. After obtaining molecular remission, he underwent autologous peripheral blood stem cell transplantation (PBSCT) with busulfan and melphalan conditioning. The transplant dose of CD 34-positive cells was sufficient, and engraftment was prompt.

Expression patterns of microRNAs 155 and 451 during normal human erythropoiesis.

To clarify the roles of microRNAs (miRNAs) in erythropoiesis, the expression of miR-155, miR-221, miR-223, and miR-451 were analyzed during the differentiation of purified normal human erythroid progenitors in a liquid culture system. Cells increased almost 500-fold in a number, and differentiated to benzidine-positive mature erythroblasts. Analyses of miRNA expression using the quantitative real-time polymerase chain reaction showed that the expression level of miR-155 decreased about 200-fold, and that the expression of miR-451 increased about 270-fold during 12 days of cultures.

[Human herpesvirus 6 encephalitis in a patient with adult T-cell leukemia/lymphoma].

Human herpesvirus 6 (HHV-6) reactivates in immunocompromised patients, and HHV-6 encephalitis has often been reported as a complication of transplantation. We describe a 37-year-old woman with the acute type of adult T-cell leukemia/lymphoma who developed HHV-6 encephalitis before chemotherapy. The patient's main symptoms were disorientation and short-term memory loss.

Mortalin is a novel mediator of erythropoietin signaling.

Erythropoietin (EPO) stimulates erythroid growth by enhancing the proliferation, maturation and survival of late-stage erythroid progenitor cells. However, the entire process of EPO stimulation remains undetermined. To further clarify the intracellular mechanisms by which EPO affects the growth of erythroid progenitor cells, we analyzed proteins obtained from purified human erythroid colony-forming cells (ECFCs) cultured with or without EPO, and one of the proteins apparently related with EPO stimuli was identified as mortalin (mthsp70/PBP74/Grp75/mot-2), which is a member of the heat shock protein 70 family of chaperones.

[Second nonmyeloablative allogeneic peripheral blood stem cell transplantation with more immunosuppressive conditioning regimen for the late graft failure of the patient with acute myeloid leukemia].

A 53-year-old woman with acute myeloid leukemia (M2; normal karyotype) in first remission underwent the nonmyeloablative allogeneic peripheral blood stem cell transplantation from her HLA-identical brother, with conditioning consisting of fludarabine and low dose total body irradiation (2Gy). Karyotype analysis of bone marrow on day 28 after the recovery of the hematopoiesis showed 46 XY (20/20). However, pancytopenia progressed from day 130 and the patient became transfusion dependent.

[Follicular lymphoma complicated with autoimmune hemolytic anemia and pure red cell aplasia].

Malignant lymphomas are often associated with immunological disorders. We describe here a 54-year-old woman with follicular lymphoma, simultaneously complicated with autoimmune hemolytic anemia and pure red cell aplasia. The patient had bilateral cervical, axillar and inguinal lymph node swellings.

[Nonmyeloablative allogeneic stem cell transplantation for a 70-year-old woman with relapsed acute myelogenous leukemia].

We describe a 70-year-old woman with acute myelogenous leukemia with t(8;21) in the first relapse who underwent nonmyeloablative transplantation with conditioning of fludarabine and low-dose total body irradiation (2Gy). Myelosuppression was very mild, and the patient developed transient grade I renal and hepatic toxicities. Complete chimerism was achieved on day 120.

Successful treatment with nonmyeloablative allogeneic hematopoietic stem cell transplantation in a patient with acute myeloid leukemia complicated with pulmonary infection.

We describe the case of a 48-year-old man with acute myeloid leukemia complicated with pulmonary infection that was successfully treated by nonmyeloablative allogeneic peripheral blood stem cell transplantation with conditioning by low-dose total body irradiation and fludarabine. The disease was diagnosed immunophenotypically as myeloid/natural killer cell precursor acute leukemia. After two courses of induction therapy, complete remission was achieved.